12345678910111213141516171819202122232425262728293031323334353637383940414243444546474849505152535455565758596061626364656667686970717273747576777879808182838485868788899091929394959697989910010110210310410510610710810911011111211311411511611711811912012112212312412512612712812913013113213313413513613713813914014114214314414514614714814915015115215315415515615715815916016116216316416516616716816917017117217317417517617717817918018118218318418518618718818919019119219319419519619719819920020120220320420520620720820921021121221321421521621721821922022122222322422522622722822923023123223323423523623723823924024124224324424524624724824925025125225325425525625725825926026126226326426526626726826927027127227327427527627727827928028128228328428528628728828929029129229329429529629729829930030130230330430530630730830931031131231331431531631731831932032132232332432532632732832933033133233333433533633733833934034134234334434534634734834935035135235335435535635735835936036136236336436536636736836937037137237337437537637737837938038138238338438538638738838939039139239339439539639739839940040140240340440540640740840941041141241341441541641741841942042142242342442542642742842943043143243343443543643743843944044144244344444544644744844945045145245345445545645745845946046146246346446546646746846947047147247347447547647747847948048148248348448548648748848949049149249349449549649749849950050150250350450550650750850951051151251351451551651751851952052152252352452552652752852953053153253353453553653753853954054154254354454554654754854955055155255355455555655755855956056156256356456556656756856957057157257357457557657757857958058158258358458558658758858959059159259359459559659759859960060160260360460560660760860961061161261361461561661761861962062162262362462562662762862963063163263363463563663763863964064164264364464564664764864965065165265365465565665765865966066166266366466566666766866967067167267367467567667767867968068168268368468568668768868969069169269369469569669769869970070170270370470570670770870971071171271371471571671771871972072172272372472572672772872973073173273373473573673773873974074174274374474574674774874975075175275375475575675775875976076176276376476576676776876977077177277377477577677777877978078178278378478578678778878979079179279379479579679779879980080180280380480580680780880981081181281381481581681781881982082182282382482582682782882983083183283383483583683783883984084184284384484584684784884985085185285385485585685785885986086186286386486586686786886987087187287387487587687787887988088188288388488588688788888989089189289389489589689789889990090190290390490590690790890991091191291391491591691791891992092192292392492592692792892993093193293393493593693793893994094194294394494594694794894995095195295395495595695795895996096196296396496596696796896997097197297397497597697797897998098198298398498598698798898999099199299399499599699799899910001001100210031004100510061007100810091010101110121013101410151016101710181019102010211022102310241025102610271028102910301031103210331034103510361037103810391040104110421043104410451046104710481049105010511052105310541055105610571058105910601061106210631064106510661067106810691070107110721073107410751076107710781079108010811082108310841085108610871088108910901091109210931094109510961097109810991100110111021103110411051106110711081109111011111112111311141115111611171118111911201121112211231124112511261127112811291130113111321133113411351136113711381139114011411142114311441145114611471148114911501151115211531154115511561157115811591160116111621163116411651166116711681169117011711172117311741175117611771178117911801181118211831184118511861187118811891190119111921193119411951196119711981199120012011202120312041205120612071208120912101211121212131214121512161217121812191220122112221223122412251226122712281229123012311232123312341235123612371238123912401241124212431244124512461247124812491250125112521253125412551256125712581259126012611262126312641265126612671268126912701271127212731274127512761277127812791280128112821283128412851286128712881289129012911292129312941295129612971298129913001301130213031304130513061307130813091310131113121313131413151316131713181319132013211322132313241325132613271328132913301331133213331334133513361337133813391340134113421343134413451346134713481349135013511352135313541355135613571358135913601361136213631364136513661367136813691370137113721373137413751376137713781379138013811382138313841385138613871388138913901391139213931394139513961397139813991400140114021403140414051406140714081409141014111412141314141415141614171418141914201421142214231424142514261427142814291430143114321433143414351436143714381439144014411442144314441445144614471448144914501451145214531454145514561457145814591460146114621463146414651466146714681469147014711472147314741475147614771478147914801481148214831484148514861487148814891490149114921493149414951496149714981499150015011502150315041505150615071508150915101511151215131514151515161517151815191520152115221523152415251526152715281529153015311532153315341535153615371538153915401541154215431544154515461547154815491550155115521553155415551556155715581559156015611562156315641565156615671568156915701571157215731574157515761577157815791580158115821583158415851586158715881589159015911592159315941595159615971598159916001601160216031604160516061607160816091610161116121613161416151616161716181619162016211622162316241625162616271628162916301631163216331634163516361637163816391640164116421643164416451646164716481649165016511652165316541655165616571658165916601661166216631664166516661667166816691670167116721673167416751676167716781679168016811682168316841685168616871688168916901691169216931694169516961697169816991700170117021703170417051706170717081709171017111712171317141715171617171718171917201721172217231724172517261727172817291730173117321733173417351736173717381739174017411742174317441745174617471748174917501751175217531754175517561757175817591760176117621763176417651766176717681769177017711772177317741775177617771778177917801781178217831784178517861787178817891790179117921793179417951796179717981799180018011802180318041805180618071808180918101811181218131814181518161817181818191820182118221823182418251826182718281829183018311832183318341835183618371838183918401841184218431844184518461847184818491850185118521853185418551856185718581859186018611862186318641865186618671868186918701871187218731874187518761877187818791880188118821883188418851886188718881889189018911892189318941895189618971898189919001901190219031904190519061907190819091910191119121913191419151916191719181919192019211922192319241925192619271928192919301931193219331934193519361937193819391940194119421943194419451946194719481949195019511952195319541955195619571958195919601961196219631964196519661967196819691970197119721973197419751976197719781979198019811982198319841985198619871988198919901991199219931994199519961997199819992000200120022003200420052006200720082009201020112012201320142015201620172018201920202021202220232024202520262027202820292030203120322033203420352036203720382039204020412042204320442045204620472048204920502051205220532054205520562057205820592060206120622063206420652066206720682069207020712072207320742075207620772078207920802081208220832084208520862087208820892090209120922093209420952096209720982099210021012102210321042105210621072108210921102111211221132114211521162117211821192120212121222123212421252126212721282129213021312132213321342135213621372138213921402141214221432144214521462147214821492150215121522153215421552156215721582159216021612162216321642165216621672168216921702171217221732174217521762177217821792180218121822183218421852186218721882189219021912192219321942195219621972198219922002201220222032204220522062207220822092210221122122213221422152216221722182219222022212222222322242225222622272228222922302231223222332234223522362237223822392240224122422243224422452246224722482249225022512252225322542255225622572258225922602261226222632264226522662267226822692270227122722273227422752276227722782279228022812282228322842285228622872288228922902291229222932294229522962297229822992300230123022303230423052306230723082309231023112312231323142315231623172318231923202321232223232324232523262327232823292330233123322333233423352336233723382339234023412342234323442345234623472348234923502351235223532354235523562357235823592360236123622363236423652366236723682369237023712372237323742375237623772378237923802381238223832384238523862387238823892390239123922393239423952396239723982399240024012402240324042405240624072408240924102411241224132414241524162417241824192420242124222423242424252426242724282429243024312432243324342435243624372438243924402441244224432444244524462447244824492450245124522453245424552456245724582459246024612462246324642465246624672468246924702471247224732474247524762477247824792480248124822483248424852486248724882489249024912492249324942495249624972498249925002501250225032504250525062507250825092510251125122513251425152516251725182519252025212522252325242525252625272528252925302531253225332534253525362537253825392540254125422543254425452546254725482549255025512552255325542555255625572558255925602561256225632564256525662567256825692570257125722573257425752576257725782579258025812582258325842585258625872588258925902591259225932594259525962597259825992600260126022603260426052606260726082609261026112612261326142615261626172618261926202621262226232624262526262627262826292630263126322633263426352636263726382639264026412642264326442645264626472648264926502651265226532654265526562657265826592660266126622663266426652666266726682669267026712672267326742675267626772678267926802681268226832684268526862687268826892690269126922693269426952696269726982699270027012702270327042705270627072708270927102711271227132714271527162717271827192720272127222723272427252726272727282729273027312732273327342735273627372738273927402741274227432744274527462747274827492750275127522753275427552756275727582759276027612762276327642765276627672768276927702771277227732774277527762777277827792780278127822783278427852786278727882789279027912792279327942795279627972798279928002801280228032804280528062807280828092810281128122813281428152816281728182819282028212822282328242825282628272828282928302831283228332834283528362837283828392840284128422843284428452846284728482849285028512852285328542855285628572858285928602861286228632864286528662867286828692870287128722873287428752876287728782879288028812882288328842885288628872888288928902891289228932894289528962897289828992900290129022903290429052906290729082909291029112912291329142915291629172918291929202921292229232924292529262927292829292930293129322933293429352936293729382939294029412942294329442945294629472948294929502951295229532954295529562957295829592960296129622963296429652966296729682969297029712972297329742975297629772978297929802981298229832984298529862987298829892990299129922993299429952996299729982999300030013002300330043005300630073008300930103011301230133014301530163017301830193020302130223023302430253026302730283029303030313032303330343035303630373038303930403041304230433044304530463047304830493050305130523053305430553056305730583059306030613062306330643065306630673068306930703071307230733074307530763077307830793080308130823083308430853086308730883089309030913092309330943095309630973098309931003101310231033104310531063107310831093110311131123113311431153116311731183119312031213122312331243125312631273128312931303131313231333134313531363137313831393140314131423143314431453146314731483149315031513152315331543155315631573158315931603161316231633164316531663167316831693170317131723173317431753176317731783179318031813182318331843185318631873188318931903191319231933194319531963197319831993200320132023203320432053206320732083209321032113212321332143215321632173218321932203221322232233224322532263227322832293230323132323233323432353236323732383239324032413242324332443245324632473248324932503251325232533254325532563257325832593260326132623263326432653266326732683269327032713272327332743275327632773278327932803281328232833284328532863287328832893290329132923293329432953296329732983299330033013302330333043305330633073308330933103311331233133314331533163317331833193320332133223323332433253326332733283329333033313332333333343335333633373338333933403341334233433344334533463347334833493350335133523353335433553356335733583359336033613362336333643365336633673368336933703371337233733374337533763377337833793380338133823383338433853386338733883389339033913392339333943395339633973398339934003401340234033404340534063407340834093410341134123413341434153416341734183419342034213422342334243425342634273428342934303431343234333434343534363437343834393440344134423443344434453446344734483449345034513452345334543455345634573458345934603461346234633464346534663467346834693470347134723473347434753476347734783479348034813482348334843485348634873488348934903491349234933494349534963497349834993500350135023503350435053506350735083509351035113512351335143515351635173518351935203521352235233524352535263527352835293530353135323533353435353536353735383539354035413542354335443545354635473548354935503551355235533554355535563557355835593560356135623563356435653566356735683569357035713572357335743575357635773578357935803581358235833584358535863587358835893590359135923593359435953596359735983599360036013602360336043605360636073608360936103611361236133614361536163617361836193620362136223623362436253626362736283629363036313632363336343635363636373638363936403641364236433644364536463647364836493650365136523653365436553656365736583659366036613662366336643665366636673668366936703671367236733674367536763677367836793680368136823683368436853686368736883689369036913692369336943695369636973698369937003701370237033704370537063707370837093710371137123713371437153716371737183719372037213722372337243725372637273728372937303731373237333734373537363737373837393740374137423743374437453746374737483749375037513752375337543755375637573758375937603761376237633764376537663767376837693770377137723773377437753776377737783779378037813782378337843785378637873788378937903791379237933794379537963797379837993800380138023803380438053806380738083809381038113812381338143815381638173818381938203821382238233824382538263827382838293830383138323833383438353836383738383839384038413842384338443845384638473848384938503851385238533854385538563857385838593860386138623863386438653866386738683869387038713872387338743875387638773878387938803881388238833884388538863887388838893890389138923893389438953896389738983899390039013902390339043905390639073908390939103911391239133914391539163917391839193920392139223923392439253926392739283929393039313932393339343935393639373938393939403941394239433944394539463947394839493950395139523953395439553956395739583959396039613962396339643965396639673968396939703971397239733974397539763977397839793980398139823983398439853986398739883989399039913992399339943995399639973998399940004001400240034004400540064007400840094010401140124013401440154016401740184019402040214022402340244025402640274028402940304031403240334034403540364037403840394040404140424043404440454046404740484049405040514052405340544055405640574058405940604061406240634064406540664067406840694070407140724073407440754076407740784079408040814082408340844085408640874088408940904091409240934094409540964097409840994100410141024103410441054106410741084109411041114112411341144115411641174118411941204121412241234124412541264127412841294130413141324133413441354136413741384139414041414142414341444145414641474148414941504151415241534154415541564157415841594160416141624163416441654166416741684169417041714172417341744175417641774178417941804181418241834184418541864187418841894190419141924193419441954196419741984199420042014202420342044205420642074208420942104211421242134214421542164217421842194220422142224223422442254226422742284229423042314232423342344235423642374238423942404241424242434244424542464247424842494250425142524253425442554256425742584259426042614262426342644265426642674268426942704271427242734274427542764277427842794280428142824283428442854286428742884289429042914292429342944295429642974298429943004301430243034304430543064307430843094310431143124313431443154316431743184319432043214322432343244325432643274328432943304331433243334334433543364337433843394340434143424343434443454346434743484349435043514352435343544355435643574358435943604361436243634364436543664367436843694370437143724373437443754376437743784379438043814382438343844385438643874388438943904391439243934394439543964397439843994400440144024403440444054406440744084409441044114412441344144415441644174418441944204421442244234424442544264427442844294430443144324433443444354436443744384439444044414442444344444445444644474448444944504451445244534454445544564457445844594460446144624463446444654466446744684469447044714472447344744475447644774478447944804481448244834484448544864487448844894490449144924493449444954496449744984499450045014502450345044505450645074508450945104511451245134514451545164517451845194520452145224523452445254526452745284529453045314532453345344535453645374538453945404541454245434544454545464547454845494550455145524553455445554556455745584559456045614562456345644565456645674568456945704571457245734574457545764577457845794580458145824583458445854586458745884589459045914592459345944595459645974598459946004601460246034604460546064607460846094610461146124613461446154616461746184619462046214622462346244625462646274628462946304631463246334634463546364637463846394640464146424643464446454646464746484649465046514652465346544655465646574658465946604661466246634664466546664667466846694670467146724673467446754676467746784679468046814682468346844685468646874688468946904691469246934694469546964697469846994700470147024703470447054706470747084709471047114712471347144715471647174718471947204721472247234724472547264727472847294730473147324733473447354736473747384739474047414742474347444745474647474748474947504751475247534754475547564757475847594760476147624763476447654766476747684769477047714772477347744775477647774778477947804781478247834784478547864787478847894790479147924793479447954796479747984799480048014802480348044805480648074808480948104811481248134814481548164817481848194820482148224823482448254826482748284829483048314832483348344835483648374838483948404841484248434844484548464847484848494850485148524853485448554856485748584859486048614862486348644865486648674868486948704871487248734874487548764877487848794880488148824883488448854886488748884889489048914892489348944895489648974898489949004901490249034904490549064907490849094910491149124913491449154916491749184919492049214922492349244925492649274928492949304931493249334934493549364937493849394940494149424943494449454946494749484949495049514952495349544955495649574958495949604961496249634964496549664967496849694970497149724973497449754976497749784979498049814982498349844985498649874988498949904991499249934994499549964997499849995000500150025003500450055006500750085009501050115012501350145015501650175018501950205021502250235024502550265027502850295030503150325033503450355036503750385039504050415042504350445045504650475048504950505051505250535054505550565057505850595060506150625063506450655066506750685069507050715072507350745075507650775078507950805081508250835084508550865087508850895090509150925093509450955096509750985099510051015102510351045105510651075108510951105111511251135114511551165117511851195120512151225123512451255126512751285129513051315132513351345135513651375138513951405141514251435144514551465147514851495150515151525153515451555156515751585159516051615162516351645165516651675168516951705171517251735174517551765177517851795180518151825183518451855186518751885189519051915192519351945195519651975198519952005201520252035204520552065207520852095210521152125213521452155216521752185219522052215222522352245225522652275228522952305231523252335234523552365237523852395240524152425243524452455246524752485249525052515252525352545255525652575258525952605261526252635264526552665267526852695270527152725273527452755276527752785279528052815282528352845285528652875288528952905291529252935294529552965297529852995300530153025303530453055306530753085309531053115312531353145315531653175318531953205321532253235324532553265327532853295330533153325333533453355336533753385339534053415342534353445345534653475348534953505351535253535354535553565357535853595360536153625363536453655366536753685369537053715372537353745375537653775378537953805381538253835384538553865387538853895390539153925393539453955396539753985399540054015402540354045405540654075408540954105411541254135414541554165417541854195420542154225423542454255426542754285429543054315432543354345435543654375438543954405441544254435444544554465447544854495450545154525453545454555456545754585459546054615462546354645465546654675468546954705471547254735474547554765477547854795480548154825483548454855486548754885489549054915492549354945495549654975498549955005501550255035504550555065507550855095510551155125513551455155516551755185519552055215522552355245525552655275528552955305531553255335534553555365537553855395540554155425543554455455546554755485549555055515552555355545555555655575558555955605561556255635564556555665567556855695570557155725573557455755576557755785579558055815582558355845585558655875588558955905591559255935594559555965597559855995600560156025603560456055606560756085609561056115612561356145615561656175618561956205621562256235624562556265627562856295630563156325633563456355636563756385639564056415642564356445645564656475648564956505651565256535654565556565657565856595660566156625663566456655666566756685669567056715672567356745675567656775678567956805681568256835684568556865687568856895690569156925693569456955696569756985699570057015702570357045705570657075708570957105711571257135714571557165717571857195720572157225723572457255726572757285729573057315732573357345735573657375738573957405741574257435744574557465747574857495750575157525753575457555756575757585759576057615762576357645765576657675768576957705771577257735774577557765777577857795780578157825783578457855786578757885789579057915792579357945795579657975798579958005801580258035804580558065807580858095810581158125813581458155816581758185819582058215822582358245825582658275828582958305831583258335834583558365837583858395840584158425843584458455846584758485849585058515852585358545855585658575858585958605861586258635864586558665867586858695870587158725873587458755876587758785879588058815882588358845885588658875888588958905891589258935894589558965897589858995900590159025903590459055906590759085909591059115912591359145915591659175918591959205921592259235924592559265927592859295930593159325933593459355936593759385939594059415942594359445945594659475948594959505951595259535954595559565957595859595960596159625963596459655966596759685969597059715972597359745975597659775978597959805981598259835984598559865987598859895990599159925993599459955996599759985999600060016002600360046005600660076008600960106011601260136014601560166017601860196020602160226023602460256026602760286029603060316032603360346035603660376038603960406041604260436044604560466047604860496050605160526053605460556056605760586059606060616062606360646065606660676068606960706071607260736074607560766077607860796080608160826083608460856086608760886089609060916092609360946095609660976098609961006101610261036104610561066107610861096110611161126113611461156116611761186119612061216122612361246125612661276128612961306131613261336134613561366137613861396140614161426143614461456146614761486149615061516152615361546155615661576158615961606161616261636164616561666167616861696170617161726173617461756176617761786179618061816182618361846185618661876188618961906191619261936194619561966197619861996200620162026203620462056206620762086209621062116212621362146215621662176218621962206221622262236224622562266227622862296230623162326233623462356236623762386239624062416242624362446245624662476248624962506251625262536254625562566257625862596260626162626263626462656266626762686269627062716272627362746275627662776278627962806281628262836284628562866287628862896290629162926293629462956296629762986299630063016302630363046305630663076308630963106311631263136314631563166317631863196320632163226323632463256326632763286329633063316332633363346335633663376338633963406341634263436344634563466347634863496350635163526353635463556356635763586359636063616362636363646365636663676368636963706371637263736374637563766377637863796380638163826383638463856386638763886389639063916392639363946395639663976398639964006401640264036404640564066407640864096410641164126413641464156416641764186419642064216422642364246425642664276428642964306431643264336434643564366437643864396440644164426443644464456446644764486449645064516452645364546455645664576458645964606461646264636464646564666467646864696470647164726473647464756476647764786479648064816482648364846485648664876488648964906491649264936494649564966497649864996500650165026503650465056506650765086509651065116512651365146515651665176518651965206521652265236524652565266527652865296530653165326533653465356536653765386539654065416542654365446545654665476548654965506551655265536554655565566557655865596560656165626563656465656566656765686569657065716572657365746575657665776578657965806581658265836584658565866587658865896590659165926593659465956596659765986599660066016602660366046605660666076608660966106611661266136614661566166617661866196620662166226623662466256626662766286629663066316632663366346635663666376638663966406641664266436644664566466647664866496650665166526653665466556656665766586659666066616662666366646665666666676668666966706671667266736674667566766677667866796680668166826683668466856686668766886689669066916692669366946695669666976698669967006701670267036704670567066707670867096710671167126713671467156716671767186719672067216722672367246725672667276728672967306731673267336734673567366737673867396740674167426743674467456746674767486749675067516752675367546755675667576758675967606761676267636764676567666767676867696770677167726773677467756776677767786779678067816782678367846785678667876788678967906791679267936794679567966797679867996800680168026803680468056806680768086809681068116812681368146815681668176818681968206821682268236824682568266827682868296830683168326833683468356836683768386839684068416842684368446845684668476848684968506851685268536854685568566857685868596860686168626863686468656866686768686869687068716872687368746875687668776878687968806881688268836884688568866887688868896890689168926893689468956896689768986899690069016902690369046905690669076908690969106911691269136914691569166917691869196920692169226923692469256926692769286929693069316932693369346935693669376938693969406941694269436944694569466947694869496950695169526953695469556956695769586959696069616962696369646965696669676968696969706971697269736974697569766977697869796980698169826983698469856986698769886989699069916992699369946995699669976998699970007001700270037004700570067007700870097010701170127013701470157016701770187019702070217022702370247025702670277028702970307031703270337034703570367037703870397040704170427043704470457046704770487049705070517052705370547055705670577058705970607061706270637064706570667067706870697070707170727073707470757076707770787079708070817082708370847085708670877088708970907091709270937094709570967097709870997100710171027103710471057106710771087109711071117112711371147115711671177118711971207121712271237124712571267127712871297130713171327133713471357136713771387139714071417142714371447145714671477148714971507151715271537154715571567157715871597160716171627163716471657166716771687169717071717172717371747175717671777178717971807181718271837184718571867187718871897190719171927193719471957196719771987199720072017202720372047205720672077208720972107211721272137214721572167217721872197220722172227223722472257226722772287229723072317232723372347235723672377238723972407241724272437244724572467247724872497250725172527253725472557256725772587259726072617262726372647265726672677268726972707271727272737274727572767277727872797280728172827283728472857286728772887289729072917292729372947295729672977298729973007301730273037304730573067307730873097310731173127313731473157316731773187319732073217322732373247325732673277328732973307331733273337334733573367337733873397340734173427343734473457346734773487349735073517352735373547355735673577358735973607361736273637364736573667367736873697370737173727373737473757376737773787379738073817382738373847385738673877388738973907391739273937394739573967397739873997400740174027403740474057406740774087409741074117412741374147415741674177418741974207421742274237424742574267427742874297430743174327433743474357436743774387439744074417442744374447445744674477448744974507451745274537454745574567457745874597460746174627463746474657466746774687469747074717472747374747475747674777478747974807481748274837484748574867487748874897490749174927493749474957496749774987499750075017502750375047505750675077508750975107511751275137514751575167517751875197520752175227523752475257526752775287529753075317532753375347535753675377538753975407541754275437544754575467547754875497550755175527553755475557556755775587559756075617562756375647565756675677568756975707571757275737574757575767577757875797580758175827583758475857586758775887589759075917592759375947595759675977598759976007601760276037604760576067607760876097610761176127613761476157616761776187619762076217622762376247625762676277628762976307631763276337634763576367637763876397640764176427643764476457646764776487649765076517652765376547655765676577658765976607661766276637664766576667667766876697670767176727673767476757676767776787679768076817682768376847685768676877688768976907691769276937694769576967697769876997700770177027703770477057706770777087709771077117712771377147715771677177718771977207721772277237724772577267727772877297730773177327733773477357736773777387739774077417742774377447745774677477748774977507751775277537754775577567757775877597760776177627763776477657766776777687769777077717772777377747775777677777778777977807781778277837784778577867787778877897790779177927793779477957796779777987799780078017802780378047805780678077808780978107811781278137814781578167817781878197820782178227823782478257826782778287829783078317832783378347835783678377838783978407841784278437844784578467847784878497850785178527853785478557856785778587859786078617862786378647865786678677868786978707871787278737874787578767877787878797880788178827883788478857886788778887889789078917892789378947895789678977898789979007901790279037904790579067907790879097910791179127913791479157916791779187919792079217922792379247925792679277928792979307931793279337934793579367937793879397940794179427943794479457946794779487949795079517952795379547955795679577958795979607961796279637964796579667967796879697970797179727973797479757976797779787979798079817982798379847985798679877988798979907991799279937994799579967997799879998000800180028003800480058006800780088009801080118012801380148015801680178018801980208021802280238024802580268027802880298030803180328033803480358036803780388039804080418042804380448045804680478048804980508051805280538054805580568057805880598060806180628063806480658066806780688069807080718072807380748075807680778078807980808081808280838084808580868087808880898090809180928093809480958096809780988099810081018102810381048105810681078108810981108111811281138114811581168117811881198120812181228123812481258126812781288129813081318132813381348135813681378138813981408141814281438144814581468147814881498150815181528153815481558156815781588159816081618162816381648165816681678168816981708171817281738174817581768177817881798180818181828183818481858186818781888189819081918192819381948195819681978198819982008201820282038204820582068207820882098210821182128213821482158216821782188219822082218222822382248225822682278228822982308231823282338234823582368237823882398240824182428243824482458246824782488249825082518252825382548255825682578258825982608261826282638264826582668267826882698270827182728273827482758276827782788279828082818282828382848285828682878288828982908291829282938294829582968297829882998300830183028303830483058306830783088309831083118312831383148315831683178318831983208321832283238324832583268327832883298330833183328333833483358336833783388339834083418342834383448345834683478348834983508351835283538354835583568357835883598360836183628363836483658366836783688369837083718372837383748375837683778378837983808381838283838384838583868387838883898390839183928393839483958396839783988399840084018402840384048405840684078408840984108411841284138414841584168417841884198420842184228423842484258426842784288429843084318432843384348435843684378438843984408441844284438444844584468447844884498450845184528453845484558456845784588459846084618462846384648465846684678468846984708471847284738474847584768477847884798480848184828483848484858486848784888489849084918492849384948495849684978498849985008501850285038504850585068507850885098510851185128513851485158516851785188519852085218522852385248525852685278528852985308531853285338534853585368537853885398540854185428543854485458546854785488549855085518552855385548555855685578558855985608561856285638564856585668567856885698570857185728573857485758576857785788579858085818582858385848585858685878588858985908591859285938594859585968597859885998600860186028603860486058606860786088609861086118612861386148615861686178618861986208621862286238624862586268627862886298630863186328633863486358636863786388639864086418642864386448645864686478648864986508651865286538654865586568657865886598660866186628663866486658666866786688669867086718672867386748675867686778678867986808681868286838684868586868687868886898690869186928693869486958696869786988699870087018702870387048705870687078708870987108711871287138714871587168717871887198720872187228723872487258726872787288729873087318732873387348735873687378738873987408741874287438744874587468747874887498750875187528753875487558756875787588759876087618762876387648765876687678768876987708771877287738774877587768777877887798780878187828783878487858786878787888789879087918792879387948795879687978798879988008801880288038804880588068807880888098810881188128813881488158816881788188819882088218822882388248825882688278828882988308831883288338834883588368837883888398840884188428843884488458846884788488849885088518852885388548855885688578858885988608861886288638864886588668867886888698870887188728873887488758876887788788879888088818882888388848885888688878888888988908891889288938894889588968897889888998900890189028903890489058906890789088909891089118912891389148915891689178918891989208921892289238924892589268927892889298930893189328933893489358936893789388939894089418942894389448945894689478948894989508951895289538954895589568957895889598960896189628963896489658966896789688969897089718972897389748975897689778978897989808981898289838984898589868987898889898990899189928993899489958996899789988999900090019002900390049005900690079008900990109011901290139014901590169017901890199020902190229023902490259026902790289029903090319032903390349035903690379038903990409041904290439044904590469047904890499050905190529053905490559056905790589059906090619062906390649065906690679068906990709071907290739074907590769077907890799080908190829083908490859086908790889089909090919092909390949095909690979098909991009101910291039104910591069107910891099110911191129113911491159116911791189119912091219122912391249125912691279128912991309131913291339134913591369137913891399140914191429143914491459146914791489149915091519152915391549155915691579158915991609161916291639164916591669167916891699170917191729173917491759176917791789179918091819182918391849185918691879188918991909191919291939194919591969197919891999200920192029203920492059206920792089209921092119212921392149215921692179218921992209221922292239224922592269227922892299230923192329233923492359236923792389239924092419242924392449245924692479248924992509251925292539254925592569257925892599260926192629263926492659266926792689269927092719272927392749275927692779278927992809281928292839284928592869287928892899290929192929293929492959296929792989299930093019302930393049305930693079308930993109311931293139314931593169317931893199320932193229323932493259326932793289329933093319332933393349335933693379338933993409341934293439344934593469347934893499350935193529353935493559356935793589359936093619362936393649365936693679368936993709371937293739374937593769377937893799380938193829383938493859386938793889389939093919392939393949395939693979398939994009401940294039404940594069407940894099410941194129413941494159416941794189419942094219422942394249425942694279428942994309431943294339434943594369437943894399440944194429443944494459446944794489449945094519452945394549455945694579458945994609461946294639464946594669467946894699470947194729473947494759476947794789479948094819482948394849485948694879488948994909491949294939494949594969497949894999500950195029503950495059506950795089509951095119512951395149515951695179518951995209521952295239524952595269527952895299530953195329533953495359536953795389539954095419542954395449545954695479548954995509551955295539554955595569557955895599560956195629563956495659566956795689569957095719572957395749575957695779578957995809581958295839584958595869587958895899590959195929593959495959596959795989599960096019602960396049605960696079608960996109611961296139614961596169617961896199620962196229623962496259626962796289629963096319632963396349635963696379638963996409641964296439644964596469647964896499650965196529653965496559656965796589659966096619662966396649665966696679668966996709671967296739674967596769677967896799680968196829683968496859686968796889689969096919692969396949695969696979698969997009701970297039704970597069707970897099710971197129713971497159716971797189719972097219722972397249725972697279728972997309731973297339734973597369737973897399740974197429743974497459746974797489749975097519752975397549755975697579758975997609761976297639764976597669767976897699770977197729773977497759776977797789779978097819782978397849785978697879788978997909791979297939794979597969797979897999800980198029803980498059806980798089809981098119812981398149815981698179818981998209821982298239824982598269827982898299830983198329833983498359836983798389839984098419842984398449845984698479848984998509851985298539854985598569857985898599860986198629863986498659866986798689869987098719872987398749875987698779878987998809881988298839884988598869887988898899890989198929893989498959896989798989899990099019902990399049905990699079908990999109911991299139914991599169917991899199920992199229923992499259926992799289929993099319932993399349935993699379938993999409941994299439944994599469947994899499950995199529953995499559956995799589959996099619962996399649965996699679968996999709971997299739974997599769977997899799980998199829983998499859986998799889989999099919992999399949995999699979998999910000100011000210003100041000510006100071000810009100101001110012100131001410015100161001710018100191002010021100221002310024100251002610027100281002910030100311003210033100341003510036100371003810039100401004110042100431004410045100461004710048100491005010051100521005310054100551005610057100581005910060100611006210063100641006510066100671006810069100701007110072100731007410075100761007710078100791008010081100821008310084100851008610087100881008910090100911009210093100941009510096100971009810099101001010110102101031010410105101061010710108101091011010111101121011310114101151011610117101181011910120 |
- /*
- This file is part of GNUnet.
- Copyright (C) 2010-2016, 2018, 2019 GNUnet e.V.
- GNUnet is free software: you can redistribute it and/or modify it
- under the terms of the GNU Affero General Public License as published
- by the Free Software Foundation, either version 3 of the License,
- or (at your option) any later version.
- GNUnet is distributed in the hope that it will be useful, but
- WITHOUT ANY WARRANTY; without even the implied warranty of
- MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
- Affero General Public License for more details.
- You should have received a copy of the GNU Affero General Public License
- along with this program. If not, see <http://www.gnu.org/licenses/>.
- SPDX-License-Identifier: AGPL3.0-or-later
- */
- /**
- * @file transport/gnunet-service-tng.c
- * @brief main for gnunet-service-tng
- * @author Christian Grothoff
- *
- * TODO:
- * Implement next:
- * - review retransmission logic, right now there is no smartness there!
- * => congestion control, etc [PERFORMANCE-BASICS]
- *
- * Optimizations-Statistics:
- * - Track ACK losses based on ACK-counter [ROUTING]
- * - Need to track total bandwidth per VirtualLink and adjust how frequently
- * we send FC messages based on bandwidth-delay-product (and relation
- * to the window size!). See OPTIMIZE-FC-BDP.
- * - Consider more statistics in #check_connection_quality() [FIXME-CONQ-STATISTICS]
- * - Adapt available_fc_window_size, using larger values for high-bandwidth
- * and high-latency links *if* we have the RAM [GOODPUT / utilization / stalls]
- * - Set last_window_consum_limit promise properly based on
- * latency and bandwidth of the respective connection [GOODPUT / utilization / stalls]
- *
- * Optimizations-DV:
- * - When forwarding DV learn messages, if a peer is reached that
- * has a *bidirectional* link to the origin beyond 1st hop,
- * do NOT forward it to peers _other_ than the origin, as
- * there is clearly a better path directly from the origin to
- * whatever else we could reach.
- * - When we passively learned DV (with unconfirmed freshness), we
- * right now add the path to our list but with a zero path_valid_until
- * time and only use it for unconfirmed routes. However, we could consider
- * triggering an explicit validation mechansim ourselves, specifically routing
- * a challenge-response message over the path [ROUTING]
- * = if available, try to confirm unconfirmed DV paths when trying to establish
- * virtual link for a `struct IncomingRequest`. (i.e. if DVH is
- * unconfirmed, incoming requests cause us to try to validate a passively
- * learned path (requires new message type!))
- *
- * Optimizations-Fragmentation:
- * - Fragments send over a reliable channel could do without the
- * AcknowledgementUUIDP altogether, as they won't be acked! [BANDWIDTH]
- * (-> have 2nd type of acknowledgment message; low priority, as we
- * do not have an MTU-limited *reliable* communicator) [FIXME-FRAG-REL-UUID]
- * - if messages are below MTU, consider adding ACKs and other stuff
- * to the same transmission to avoid tiny messages (requires planning at
- * receiver, and additional MST-style demultiplex at receiver!) [PACKET COUNT]
- *
- * Optimizations-internals:
- * - queue_send_msg by API design has to make a copy
- * of the payload, and route_message on top of that requires a malloc/free.
- * Change design to approximate "zero" copy better... [CPU]
- * - could avoid copying body of message into each fragment and keep
- * fragments as just pointers into the original message and only
- * fully build fragments just before transmission (optimization, should
- * reduce CPU and memory use) [CPU, MEMORY]
- */
- #include "platform.h"
- #include "gnunet_util_lib.h"
- #include "gnunet_statistics_service.h"
- #include "gnunet_transport_monitor_service.h"
- #include "gnunet_peerstore_service.h"
- #include "gnunet_hello_lib.h"
- #include "gnunet_signatures.h"
- #include "transport.h"
- /**
- * Maximum number of messages we acknowledge together in one
- * cummulative ACK. Larger values may save a bit of bandwidth.
- */
- #define MAX_CUMMULATIVE_ACKS 64
- /**
- * What is the 1:n chance that we send a Flow control response when
- * receiving a flow control message that did not change anything for
- * us? Basically, this is used in the case where both peers are stuck
- * on flow control (no window changes), but one might continue sending
- * flow control messages to the other peer as the first FC message
- * when things stalled got lost, and then subsequently the other peer
- * does *usually* not respond as nothing changed. So to ensure that
- * eventually the FC messages stop, we do send with 1/8th probability
- * an FC message even if nothing changed. That prevents one peer
- * being stuck in sending (useless) FC messages "forever".
- */
- #define FC_NO_CHANGE_REPLY_PROBABILITY 8
- /**
- * What is the size we assume for a read operation in the
- * absence of an MTU for the purpose of flow control?
- */
- #define IN_PACKET_SIZE_WITHOUT_MTU 128
- /**
- * Number of slots we keep of historic data for computation of
- * goodput / message loss ratio.
- */
- #define GOODPUT_AGING_SLOTS 4
- /**
- * How big is the flow control window size by default;
- * limits per-neighbour RAM utilization.
- */
- #define DEFAULT_WINDOW_SIZE (128 * 1024)
- /**
- * For how many incoming connections do we try to create a
- * virtual link for (at the same time!). This does NOT
- * limit the number of incoming connections, just the number
- * for which we are actively trying to find working addresses
- * in the absence (!) of our own applications wanting the
- * link to go up.
- */
- #define MAX_INCOMING_REQUEST 16
- /**
- * Maximum number of peers we select for forwarding DVInit
- * messages at the same time (excluding initiator).
- */
- #define MAX_DV_DISCOVERY_SELECTION 16
- /**
- * Window size. How many messages to the same target do we pass
- * to CORE without a RECV_OK in between? Small values limit
- * thoughput, large values will increase latency.
- *
- * FIXME-OPTIMIZE: find out what good values are experimentally,
- * maybe set adaptively (i.e. to observed available bandwidth).
- */
- #define RECV_WINDOW_SIZE 4
- /**
- * Minimum number of hops we should forward DV learn messages
- * even if they are NOT useful for us in hope of looping
- * back to the initiator?
- *
- * FIXME: allow initiator some control here instead?
- */
- #define MIN_DV_PATH_LENGTH_FOR_INITIATOR 3
- /**
- * Maximum DV distance allowed ever.
- */
- #define MAX_DV_HOPS_ALLOWED 16
- /**
- * Maximum number of DV learning activities we may
- * have pending at the same time.
- */
- #define MAX_DV_LEARN_PENDING 64
- /**
- * Maximum number of DV paths we keep simultaneously to the same target.
- */
- #define MAX_DV_PATHS_TO_TARGET 3
- /**
- * If a queue delays the next message by more than this number
- * of seconds we log a warning. Note: this is for testing,
- * the value chosen here might be too aggressively low!
- */
- #define DELAY_WARN_THRESHOLD \
- GNUNET_TIME_relative_multiply (GNUNET_TIME_UNIT_SECONDS, 5)
- /**
- * If a DVBox could not be forwarded after this number of
- * seconds we drop it.
- */
- #define DV_FORWARD_TIMEOUT \
- GNUNET_TIME_relative_multiply (GNUNET_TIME_UNIT_SECONDS, 60)
- /**
- * We only consider queues as "quality" connections when
- * suppressing the generation of DV initiation messages if
- * the latency of the queue is below this threshold.
- */
- #define DV_QUALITY_RTT_THRESHOLD \
- GNUNET_TIME_relative_multiply (GNUNET_TIME_UNIT_SECONDS, 1)
- /**
- * How long do we consider a DV path valid if we see no
- * further updates on it? Note: the value chosen here might be too low!
- */
- #define DV_PATH_VALIDITY_TIMEOUT \
- GNUNET_TIME_relative_multiply (GNUNET_TIME_UNIT_MINUTES, 5)
- /**
- * How long do we cache backchannel (struct Backtalker) information
- * after a backchannel goes inactive?
- */
- #define BACKCHANNEL_INACTIVITY_TIMEOUT \
- GNUNET_TIME_relative_multiply (GNUNET_TIME_UNIT_MINUTES, 5)
- /**
- * How long before paths expire would we like to (re)discover DV paths? Should
- * be below #DV_PATH_VALIDITY_TIMEOUT.
- */
- #define DV_PATH_DISCOVERY_FREQUENCY \
- GNUNET_TIME_relative_multiply (GNUNET_TIME_UNIT_MINUTES, 4)
- /**
- * How long are ephemeral keys valid?
- */
- #define EPHEMERAL_VALIDITY \
- GNUNET_TIME_relative_multiply (GNUNET_TIME_UNIT_HOURS, 4)
- /**
- * How long do we keep partially reassembled messages around before giving up?
- */
- #define REASSEMBLY_EXPIRATION \
- GNUNET_TIME_relative_multiply (GNUNET_TIME_UNIT_MINUTES, 4)
- /**
- * What is the fastest rate at which we send challenges *if* we keep learning
- * an address (gossip, DHT, etc.)?
- */
- #define FAST_VALIDATION_CHALLENGE_FREQ \
- GNUNET_TIME_relative_multiply (GNUNET_TIME_UNIT_MINUTES, 1)
- /**
- * What is the slowest rate at which we send challenges?
- */
- #define MAX_VALIDATION_CHALLENGE_FREQ \
- GNUNET_TIME_relative_multiply (GNUNET_TIME_UNIT_DAYS, 1)
- /**
- * How long until we forget about historic accumulators and thus
- * reset the ACK counter? Should exceed the maximum time an
- * active connection experiences without an ACK.
- */
- #define ACK_CUMMULATOR_TIMEOUT \
- GNUNET_TIME_relative_multiply (GNUNET_TIME_UNIT_HOURS, 4)
- /**
- * What is the non-randomized base frequency at which we
- * would initiate DV learn messages?
- */
- #define DV_LEARN_BASE_FREQUENCY GNUNET_TIME_UNIT_MINUTES
- /**
- * How many good connections (confirmed, bi-directional, not DV)
- * do we need to have to suppress initiating DV learn messages?
- */
- #define DV_LEARN_QUALITY_THRESHOLD 100
- /**
- * When do we forget an invalid address for sure?
- */
- #define MAX_ADDRESS_VALID_UNTIL \
- GNUNET_TIME_relative_multiply (GNUNET_TIME_UNIT_MONTHS, 1)
- /**
- * How long do we consider an address valid if we just checked?
- */
- #define ADDRESS_VALIDATION_LIFETIME \
- GNUNET_TIME_relative_multiply (GNUNET_TIME_UNIT_HOURS, 4)
- /**
- * What is the maximum frequency at which we do address validation?
- * A random value between 0 and this value is added when scheduling
- * the #validation_task (both to ensure we do not validate too often,
- * and to randomize a bit).
- */
- #define MIN_DELAY_ADDRESS_VALIDATION GNUNET_TIME_UNIT_MILLISECONDS
- /**
- * How many network RTTs before an address validation expires should we begin
- * trying to revalidate? (Note that the RTT used here is the one that we
- * experienced during the last validation, not necessarily the latest RTT
- * observed).
- */
- #define VALIDATION_RTT_BUFFER_FACTOR 3
- /**
- * How many messages can we have pending for a given communicator
- * process before we start to throttle that communicator?
- *
- * Used if a communicator might be CPU-bound and cannot handle the traffic.
- */
- #define COMMUNICATOR_TOTAL_QUEUE_LIMIT 512
- /**
- * How many messages can we have pending for a given queue (queue to
- * a particular peer via a communicator) process before we start to
- * throttle that queue?
- */
- #define QUEUE_LENGTH_LIMIT 32
- GNUNET_NETWORK_STRUCT_BEGIN
- /**
- * Unique identifier we attach to a message.
- */
- struct MessageUUIDP
- {
- /**
- * Unique value, generated by incrementing the
- * `message_uuid_ctr` of `struct Neighbour`.
- */
- uint64_t uuid GNUNET_PACKED;
- };
- /**
- * Unique identifier to map an acknowledgement to a transmission.
- */
- struct AcknowledgementUUIDP
- {
- /**
- * The UUID value.
- */
- struct GNUNET_Uuid value;
- };
- /**
- * Outer layer of an encapsulated backchannel message.
- */
- struct TransportBackchannelEncapsulationMessage
- {
- /**
- * Type is #GNUNET_MESSAGE_TYPE_TRANSPORT_BACKCHANNEL_ENCAPSULATION.
- */
- struct GNUNET_MessageHeader header;
- /* Followed by *another* message header which is the message to
- the communicator */
- /* Followed by a 0-terminated name of the communicator */
- };
- /**
- * Body by which a peer confirms that it is using an ephemeral key.
- */
- struct EphemeralConfirmationPS
- {
- /**
- * Purpose is #GNUNET_SIGNATURE_PURPOSE_TRANSPORT_EPHEMERAL
- */
- struct GNUNET_CRYPTO_EccSignaturePurpose purpose;
- /**
- * How long is this signature over the ephemeral key valid?
- *
- * Note that the receiver MUST IGNORE the absolute time, and only interpret
- * the value as a mononic time and reject "older" values than the last one
- * observed. This is necessary as we do not want to require synchronized
- * clocks and may not have a bidirectional communication channel.
- *
- * Even with this, there is no real guarantee against replay achieved here,
- * unless the latest timestamp is persisted. While persistence should be
- * provided via PEERSTORE, we do not consider the mechanism reliable! Thus,
- * communicators must protect against replay attacks when using backchannel
- * communication!
- */
- struct GNUNET_TIME_AbsoluteNBO sender_monotonic_time;
- /**
- * Target's peer identity.
- */
- struct GNUNET_PeerIdentity target;
- /**
- * Ephemeral key setup by the sender for @e target, used
- * to encrypt the payload.
- */
- struct GNUNET_CRYPTO_EcdhePublicKey ephemeral_key;
- };
- /**
- * Plaintext of the variable-size payload that is encrypted
- * within a `struct TransportBackchannelEncapsulationMessage`
- */
- struct TransportDVBoxPayloadP
- {
- /**
- * Sender's peer identity.
- */
- struct GNUNET_PeerIdentity sender;
- /**
- * Signature of the sender over an
- * #GNUNET_SIGNATURE_PURPOSE_TRANSPORT_EPHEMERAL.
- */
- struct GNUNET_CRYPTO_EddsaSignature sender_sig;
- /**
- * Current monotonic time of the sending transport service. Used to
- * detect replayed messages. Note that the receiver should remember
- * a list of the recently seen timestamps and only reject messages
- * if the timestamp is in the list, or the list is "full" and the
- * timestamp is smaller than the lowest in the list.
- *
- * Like the @e ephemeral_validity, the list of timestamps per peer should be
- * persisted to guard against replays after restarts.
- */
- struct GNUNET_TIME_AbsoluteNBO monotonic_time;
- /* Followed by a `struct GNUNET_MessageHeader` with a message
- for the target peer */
- };
- /**
- * Outer layer of an encapsulated unfragmented application message sent
- * over an unreliable channel.
- */
- struct TransportReliabilityBoxMessage
- {
- /**
- * Type is #GNUNET_MESSAGE_TYPE_TRANSPORT_RELIABILITY_BOX
- */
- struct GNUNET_MessageHeader header;
- /**
- * Number of messages still to be sent before a commulative
- * ACK is requested. Zero if an ACK is requested immediately.
- * In NBO. Note that the receiver may send the ACK faster
- * if it believes that is reasonable.
- */
- uint32_t ack_countdown GNUNET_PACKED;
- /**
- * Unique ID of the message used for signalling receipt of
- * messages sent over possibly unreliable channels. Should
- * be a random.
- */
- struct AcknowledgementUUIDP ack_uuid;
- };
- /**
- * Acknowledgement payload.
- */
- struct TransportCummulativeAckPayloadP
- {
- /**
- * How long was the ACK delayed for generating cummulative ACKs?
- * Used to calculate the correct network RTT by taking the receipt
- * time of the ack minus the transmission time of the sender minus
- * this value.
- */
- struct GNUNET_TIME_RelativeNBO ack_delay;
- /**
- * UUID of a message being acknowledged.
- */
- struct AcknowledgementUUIDP ack_uuid;
- };
- /**
- * Confirmation that the receiver got a
- * #GNUNET_MESSAGE_TYPE_TRANSPORT_RELIABILITY_BOX. Note that the
- * confirmation may be transmitted over a completely different queue,
- * so ACKs are identified by a combination of PID of sender and
- * message UUID, without the queue playing any role!
- */
- struct TransportReliabilityAckMessage
- {
- /**
- * Type is #GNUNET_MESSAGE_TYPE_TRANSPORT_RELIABILITY_ACK
- */
- struct GNUNET_MessageHeader header;
- /**
- * Counter of ACKs transmitted by the sender to us. Incremented
- * by one for each ACK, used to detect how many ACKs were lost.
- */
- uint32_t ack_counter GNUNET_PACKED;
- /* followed by any number of `struct TransportCummulativeAckPayloadP`
- messages providing ACKs */
- };
- /**
- * Outer layer of an encapsulated fragmented application message.
- */
- struct TransportFragmentBoxMessage
- {
- /**
- * Type is #GNUNET_MESSAGE_TYPE_TRANSPORT_FRAGMENT
- */
- struct GNUNET_MessageHeader header;
- /**
- * Offset of this fragment in the overall message.
- */
- uint16_t frag_off GNUNET_PACKED;
- /**
- * Total size of the message that is being fragmented.
- */
- uint16_t msg_size GNUNET_PACKED;
- /**
- * Unique ID of this fragment (and fragment transmission!). Will
- * change even if a fragement is retransmitted to make each
- * transmission attempt unique! If a client receives a duplicate
- * fragment (same @e frag_off for same @a msg_uuid, it must send
- * #GNUNET_MESSAGE_TYPE_TRANSPORT_RELIABILITY_ACK immediately.
- */
- struct AcknowledgementUUIDP ack_uuid;
- /**
- * Original message ID for of the message that all the fragments
- * belong to. Must be the same for all fragments.
- */
- struct MessageUUIDP msg_uuid;
- };
- /**
- * Content signed by the initator during DV learning.
- *
- * The signature is required to prevent DDoS attacks. A peer sending out this
- * message is potentially generating a lot of traffic that will go back to the
- * initator, as peers receiving this message will try to let the initiator
- * know that they got the message.
- *
- * Without this signature, an attacker could abuse this mechanism for traffic
- * amplification, sending a lot of traffic to a peer by putting out this type
- * of message with the victim's peer identity.
- *
- * Even with just a signature, traffic amplification would be possible via
- * replay attacks. The @e monotonic_time limits such replay attacks, as every
- * potential amplificator will check the @e monotonic_time and only respond
- * (at most) once per message.
- */
- struct DvInitPS
- {
- /**
- * Purpose is #GNUNET_SIGNATURE_PURPOSE_TRANSPORT_DV_INITIATOR
- */
- struct GNUNET_CRYPTO_EccSignaturePurpose purpose;
- /**
- * Time at the initiator when generating the signature.
- *
- * Note that the receiver MUST IGNORE the absolute time, and only interpret
- * the value as a mononic time and reject "older" values than the last one
- * observed. This is necessary as we do not want to require synchronized
- * clocks and may not have a bidirectional communication channel.
- *
- * Even with this, there is no real guarantee against replay achieved here,
- * unless the latest timestamp is persisted. Persistence should be
- * provided via PEERSTORE if possible.
- */
- struct GNUNET_TIME_AbsoluteNBO monotonic_time;
- /**
- * Challenge value used by the initiator to re-identify the path.
- */
- struct ChallengeNonceP challenge;
- };
- /**
- * Content signed by each peer during DV learning.
- *
- * This assues the initiator of the DV learning operation that the hop from @e
- * pred via the signing peer to @e succ actually exists. This makes it
- * impossible for an adversary to supply the network with bogus routes.
- *
- * The @e challenge is included to provide replay protection for the
- * initiator. This way, the initiator knows that the hop existed after the
- * original @e challenge was first transmitted, providing a freshness metric.
- *
- * Peers other than the initiator that passively learn paths by observing
- * these messages do NOT benefit from this. Here, an adversary may indeed
- * replay old messages. Thus, passively learned paths should always be
- * immediately marked as "potentially stale".
- */
- struct DvHopPS
- {
- /**
- * Purpose is #GNUNET_SIGNATURE_PURPOSE_TRANSPORT_DV_HOP
- */
- struct GNUNET_CRYPTO_EccSignaturePurpose purpose;
- /**
- * Identity of the previous peer on the path.
- */
- struct GNUNET_PeerIdentity pred;
- /**
- * Identity of the next peer on the path.
- */
- struct GNUNET_PeerIdentity succ;
- /**
- * Challenge value used by the initiator to re-identify the path.
- */
- struct ChallengeNonceP challenge;
- };
- /**
- * An entry describing a peer on a path in a
- * `struct TransportDVLearnMessage` message.
- */
- struct DVPathEntryP
- {
- /**
- * Identity of a peer on the path.
- */
- struct GNUNET_PeerIdentity hop;
- /**
- * Signature of this hop over the path, of purpose
- * #GNUNET_SIGNATURE_PURPOSE_TRANSPORT_DV_HOP
- */
- struct GNUNET_CRYPTO_EddsaSignature hop_sig;
- };
- /**
- * Internal message used by transport for distance vector learning.
- * If @e num_hops does not exceed the threshold, peers should append
- * themselves to the peer list and flood the message (possibly only
- * to a subset of their neighbours to limit discoverability of the
- * network topology). To the extend that the @e bidirectional bits
- * are set, peers may learn the inverse paths even if they did not
- * initiate.
- *
- * Unless received on a bidirectional queue and @e num_hops just
- * zero, peers that can forward to the initator should always try to
- * forward to the initiator.
- */
- struct TransportDVLearnMessage
- {
- /**
- * Type is #GNUNET_MESSAGE_TYPE_TRANSPORT_DV_LEARN
- */
- struct GNUNET_MessageHeader header;
- /**
- * Number of hops this messages has travelled, in NBO. Zero if
- * sent by initiator.
- */
- uint16_t num_hops GNUNET_PACKED;
- /**
- * Bitmask of the last 16 hops indicating whether they are confirmed
- * available (without DV) in both directions or not, in NBO. Used
- * to possibly instantly learn a path in both directions. Each peer
- * should shift this value by one to the left, and then set the
- * lowest bit IF the current sender can be reached from it (without
- * DV routing).
- */
- uint16_t bidirectional GNUNET_PACKED;
- /**
- * Peers receiving this message and delaying forwarding to other
- * peers for any reason should increment this value by the non-network
- * delay created by the peer.
- */
- struct GNUNET_TIME_RelativeNBO non_network_delay;
- /**
- * Time at the initiator when generating the signature.
- *
- * Note that the receiver MUST IGNORE the absolute time, and only interpret
- * the value as a mononic time and reject "older" values than the last one
- * observed. This is necessary as we do not want to require synchronized
- * clocks and may not have a bidirectional communication channel.
- *
- * Even with this, there is no real guarantee against replay achieved here,
- * unless the latest timestamp is persisted. Persistence should be
- * provided via PEERSTORE if possible.
- */
- struct GNUNET_TIME_AbsoluteNBO monotonic_time;
- /**
- * Signature of this hop over the path, of purpose
- * #GNUNET_SIGNATURE_PURPOSE_TRANSPORT_DV_INITIATOR
- */
- struct GNUNET_CRYPTO_EddsaSignature init_sig;
- /**
- * Identity of the peer that started this learning activity.
- */
- struct GNUNET_PeerIdentity initiator;
- /**
- * Challenge value used by the initiator to re-identify the path.
- */
- struct ChallengeNonceP challenge;
- /* Followed by @e num_hops `struct DVPathEntryP` values,
- excluding the initiator of the DV trace; the last entry is the
- current sender; the current peer must not be included. */
- };
- /**
- * Outer layer of an encapsulated message send over multiple hops.
- * The path given only includes the identities of the subsequent
- * peers, i.e. it will be empty if we are the receiver. Each
- * forwarding peer should scan the list from the end, and if it can,
- * forward to the respective peer. The list should then be shortened
- * by all the entries up to and including that peer. Each hop should
- * also increment @e total_hops to allow the receiver to get a precise
- * estimate on the number of hops the message travelled. Senders must
- * provide a learned path that thus should work, but intermediaries
- * know of a shortcut, they are allowed to send the message via that
- * shortcut.
- *
- * If a peer finds itself still on the list, it must drop the message.
- *
- * The payload of the box can only be decrypted and verified by the
- * ultimate receiver. Intermediaries do not learn the sender's
- * identity and the path the message has taken. However, the first
- * hop does learn the sender as @e total_hops would be zero and thus
- * the predecessor must be the origin (so this is not really useful
- * for anonymization).
- */
- struct TransportDVBoxMessage
- {
- /**
- * Type is #GNUNET_MESSAGE_TYPE_TRANSPORT_DV_BOX
- */
- struct GNUNET_MessageHeader header;
- /**
- * Number of total hops this messages travelled. In NBO.
- * @e origin sets this to zero, to be incremented at
- * each hop. Peers should limit the @e total_hops value
- * they accept from other peers.
- */
- uint16_t total_hops GNUNET_PACKED;
- /**
- * Number of hops this messages includes. In NBO. Reduced by one
- * or more at each hop. Peers should limit the @e num_hops value
- * they accept from other peers.
- */
- uint16_t num_hops GNUNET_PACKED;
- /**
- * Ephemeral key setup by the sender for target, used to encrypt the
- * payload. Intermediaries must not change this value.
- */
- struct GNUNET_CRYPTO_EcdhePublicKey ephemeral_key;
- /**
- * We use an IV here as the @e ephemeral_key is re-used for
- * #EPHEMERAL_VALIDITY time to avoid re-signing it all the time.
- * Intermediaries must not change this value.
- */
- struct GNUNET_ShortHashCode iv;
- /**
- * HMAC over the ciphertext of the encrypted, variable-size body
- * that follows. Verified via DH of target and @e ephemeral_key.
- * Intermediaries must not change this value.
- */
- struct GNUNET_HashCode hmac;
- /* Followed by @e num_hops `struct GNUNET_PeerIdentity` values;
- excluding the @e origin and the current peer, the last must be
- the ultimate target; if @e num_hops is zero, the receiver of this
- message is the ultimate target. */
- /* Followed by encrypted, variable-size payload, which
- must begin with a `struct TransportDVBoxPayloadP` */
- /* Followed by the actual message, which itself must not be a
- a DV_LEARN or DV_BOX message! */
- };
- /**
- * Message send to another peer to validate that it can indeed
- * receive messages at a particular address.
- */
- struct TransportValidationChallengeMessage
- {
- /**
- * Type is #GNUNET_MESSAGE_TYPE_TRANSPORT_ADDRESS_VALIDATION_CHALLENGE
- */
- struct GNUNET_MessageHeader header;
- /**
- * Always zero.
- */
- uint32_t reserved GNUNET_PACKED;
- /**
- * Challenge to be signed by the receiving peer.
- */
- struct ChallengeNonceP challenge;
- /**
- * Timestamp of the sender, to be copied into the reply to allow
- * sender to calculate RTT. Must be monotonically increasing!
- */
- struct GNUNET_TIME_AbsoluteNBO sender_time;
- };
- /**
- * Message signed by a peer to confirm that it can indeed
- * receive messages at a particular address.
- */
- struct TransportValidationPS
- {
- /**
- * Purpose is #GNUNET_SIGNATURE_PURPOSE_TRANSPORT_CHALLENGE
- */
- struct GNUNET_CRYPTO_EccSignaturePurpose purpose;
- /**
- * How long does the sender believe the address on
- * which the challenge was received to remain valid?
- */
- struct GNUNET_TIME_RelativeNBO validity_duration;
- /**
- * Challenge signed by the receiving peer.
- */
- struct ChallengeNonceP challenge;
- };
- /**
- * Message send to a peer to respond to a
- * #GNUNET_MESSAGE_TYPE_ADDRESS_VALIDATION_CHALLENGE
- */
- struct TransportValidationResponseMessage
- {
- /**
- * Type is #GNUNET_MESSAGE_TYPE_TRANSPORT_ADDRESS_VALIDATION_RESPONSE
- */
- struct GNUNET_MessageHeader header;
- /**
- * Always zero.
- */
- uint32_t reserved GNUNET_PACKED;
- /**
- * The peer's signature matching the
- * #GNUNET_SIGNATURE_PURPOSE_TRANSPORT_CHALLENGE purpose.
- */
- struct GNUNET_CRYPTO_EddsaSignature signature;
- /**
- * The challenge that was signed by the receiving peer.
- */
- struct ChallengeNonceP challenge;
- /**
- * Original timestamp of the sender (was @code{sender_time}),
- * copied into the reply to allow sender to calculate RTT.
- */
- struct GNUNET_TIME_AbsoluteNBO origin_time;
- /**
- * How long does the sender believe this address to remain
- * valid?
- */
- struct GNUNET_TIME_RelativeNBO validity_duration;
- };
- /**
- * Message for Transport-to-Transport Flow control. Specifies the size
- * of the flow control window, including how much we believe to have
- * consumed (at transmission time), how much we believe to be allowed
- * (at transmission time), and how much the other peer is allowed to
- * send to us, and how much data we already received from the other
- * peer.
- */
- struct TransportFlowControlMessage
- {
- /**
- * Type is #GNUNET_MESSAGE_TYPE_TRANSPORT_FLOW_CONTROL
- */
- struct GNUNET_MessageHeader header;
- /**
- * Sequence number of the flow control message. Incremented by one
- * for each message. Starts at zero when a virtual link goes up.
- * Used to detect one-sided connection drops. On wrap-around, the
- * flow control counters will be reset as if the connection had
- * dropped.
- */
- uint32_t seq GNUNET_PACKED;
- /**
- * Flow control window size in bytes, in NBO.
- * The receiver can send this many bytes at most.
- */
- uint64_t inbound_window_size GNUNET_PACKED;
- /**
- * How many bytes has the sender sent that count for flow control at
- * this time. Used to allow the receiver to estimate the packet
- * loss rate.
- */
- uint64_t outbound_sent GNUNET_PACKED;
- /**
- * Latest flow control window size we learned from the other peer,
- * in bytes, in NBO. We are limited to sending at most this many
- * bytes to the other peer. May help the other peer detect when
- * flow control messages were lost and should thus be retransmitted.
- * In particular, if the delta to @e outbound_sent is too small,
- * this signals that we are stalled.
- */
- uint64_t outbound_window_size GNUNET_PACKED;
- /**
- * Timestamp of the sender. Must be monotonically increasing!
- * Used to enable receiver to ignore out-of-order packets in
- * combination with the @e seq. Note that @e seq will go down
- * (back to zero) whenever either side believes the connection
- * was dropped, allowing the peers to detect that they need to
- * reset the counters for the number of bytes sent!
- */
- struct GNUNET_TIME_AbsoluteNBO sender_time;
- };
- GNUNET_NETWORK_STRUCT_END
- /**
- * What type of client is the `struct TransportClient` about?
- */
- enum ClientType
- {
- /**
- * We do not know yet (client is fresh).
- */
- CT_NONE = 0,
- /**
- * Is the CORE service, we need to forward traffic to it.
- */
- CT_CORE = 1,
- /**
- * It is a monitor, forward monitor data.
- */
- CT_MONITOR = 2,
- /**
- * It is a communicator, use for communication.
- */
- CT_COMMUNICATOR = 3,
- /**
- * "Application" telling us where to connect (i.e. TOPOLOGY, DHT or CADET).
- */
- CT_APPLICATION = 4
- };
- /**
- * Which transmission options are allowable for transmission?
- * Interpreted bit-wise!
- */
- enum RouteMessageOptions
- {
- /**
- * Only confirmed, non-DV direct neighbours.
- */
- RMO_NONE = 0,
- /**
- * We are allowed to use DV routing for this @a hdr
- */
- RMO_DV_ALLOWED = 1,
- /**
- * We are allowed to use unconfirmed queues or DV routes for this message
- */
- RMO_UNCONFIRMED_ALLOWED = 2,
- /**
- * Reliable and unreliable, DV and non-DV are all acceptable.
- */
- RMO_ANYTHING_GOES = (RMO_DV_ALLOWED | RMO_UNCONFIRMED_ALLOWED),
- /**
- * If we have multiple choices, it is OK to send this message
- * over multiple channels at the same time to improve loss tolerance.
- * (We do at most 2 transmissions.)
- */
- RMO_REDUNDANT = 4
- };
- /**
- * When did we launch this DV learning activity?
- */
- struct LearnLaunchEntry
- {
- /**
- * Kept (also) in a DLL sorted by launch time.
- */
- struct LearnLaunchEntry *prev;
- /**
- * Kept (also) in a DLL sorted by launch time.
- */
- struct LearnLaunchEntry *next;
- /**
- * Challenge that uniquely identifies this activity.
- */
- struct ChallengeNonceP challenge;
- /**
- * When did we transmit the DV learn message (used to calculate RTT) and
- * determine freshness of paths learned via this operation.
- */
- struct GNUNET_TIME_Absolute launch_time;
- };
- /**
- * Information we keep per #GOODPUT_AGING_SLOTS about historic
- * (or current) transmission performance.
- */
- struct TransmissionHistoryEntry
- {
- /**
- * Number of bytes actually sent in the interval.
- */
- uint64_t bytes_sent;
- /**
- * Number of bytes received and acknowledged by the other peer in
- * the interval.
- */
- uint64_t bytes_received;
- };
- /**
- * Performance data for a transmission possibility.
- */
- struct PerformanceData
- {
- /**
- * Weighted average for the RTT.
- */
- struct GNUNET_TIME_Relative aged_rtt;
- /**
- * Historic performance data, using a ring buffer of#GOODPUT_AGING_SLOTS
- * entries.
- */
- struct TransmissionHistoryEntry the[GOODPUT_AGING_SLOTS];
- /**
- * What was the last age when we wrote to @e the? Used to clear
- * old entries when the age advances.
- */
- unsigned int last_age;
- };
- /**
- * Client connected to the transport service.
- */
- struct TransportClient;
- /**
- * A neighbour that at least one communicator is connected to.
- */
- struct Neighbour;
- /**
- * Entry in our #dv_routes table, representing a (set of) distance
- * vector routes to a particular peer.
- */
- struct DistanceVector;
- /**
- * A queue is a message queue provided by a communicator
- * via which we can reach a particular neighbour.
- */
- struct Queue;
- /**
- * Message awaiting transmission. See detailed comments below.
- */
- struct PendingMessage;
- /**
- * One possible hop towards a DV target.
- */
- struct DistanceVectorHop;
- /**
- * A virtual link is another reachable peer that is known to CORE. It
- * can be either a `struct Neighbour` with at least one confirmed
- * `struct Queue`, or a `struct DistanceVector` with at least one
- * confirmed `struct DistanceVectorHop`. With a virtual link we track
- * data that is per neighbour that is not specific to how the
- * connectivity is established.
- */
- struct VirtualLink;
- /**
- * Context from #handle_incoming_msg(). Closure for many
- * message handlers below.
- */
- struct CommunicatorMessageContext
- {
- /**
- * Kept in a DLL of `struct VirtualLink` if waiting for CORE
- * flow control to unchoke.
- */
- struct CommunicatorMessageContext *next;
- /**
- * Kept in a DLL of `struct VirtualLink` if waiting for CORE
- * flow control to unchoke.
- */
- struct CommunicatorMessageContext *prev;
- /**
- * Which communicator provided us with the message.
- */
- struct TransportClient *tc;
- /**
- * Additional information for flow control and about the sender.
- */
- struct GNUNET_TRANSPORT_IncomingMessage im;
- /**
- * Number of hops the message has travelled (if DV-routed).
- * FIXME: make use of this in ACK handling!
- */
- uint16_t total_hops;
- };
- /**
- * Closure for #core_env_sent_cb.
- */
- struct CoreSentContext
- {
- /**
- * Kept in a DLL to clear @e vl in case @e vl is lost.
- */
- struct CoreSentContext *next;
- /**
- * Kept in a DLL to clear @e vl in case @e vl is lost.
- */
- struct CoreSentContext *prev;
- /**
- * Virtual link this is about.
- */
- struct VirtualLink *vl;
- /**
- * How big was the message.
- */
- uint16_t size;
- /**
- * By how much should we increment @e vl's
- * incoming_fc_window_size_used once we are done sending to CORE?
- * Use to ensure we do not increment twice if there is more than one
- * CORE client.
- */
- uint16_t isize;
- };
- /**
- * A virtual link is another reachable peer that is known to CORE. It
- * can be either a `struct Neighbour` with at least one confirmed
- * `struct Queue`, or a `struct DistanceVector` with at least one
- * confirmed `struct DistanceVectorHop`. With a virtual link we track
- * data that is per neighbour that is not specific to how the
- * connectivity is established.
- */
- struct VirtualLink
- {
- /**
- * Identity of the peer at the other end of the link.
- */
- struct GNUNET_PeerIdentity target;
- /**
- * Communicators blocked for receiving on @e target as we are waiting
- * on the @e core_recv_window to increase.
- */
- struct CommunicatorMessageContext *cmc_head;
- /**
- * Communicators blocked for receiving on @e target as we are waiting
- * on the @e core_recv_window to increase.
- */
- struct CommunicatorMessageContext *cmc_tail;
- /**
- * Head of list of messages pending for this VL.
- */
- struct PendingMessage *pending_msg_head;
- /**
- * Tail of list of messages pending for this VL.
- */
- struct PendingMessage *pending_msg_tail;
- /**
- * Kept in a DLL to clear @e vl in case @e vl is lost.
- */
- struct CoreSentContext *csc_tail;
- /**
- * Kept in a DLL to clear @e vl in case @e vl is lost.
- */
- struct CoreSentContext *csc_head;
- /**
- * Task scheduled to possibly notfiy core that this peer is no
- * longer counting as confirmed. Runs the #core_visibility_check(),
- * which checks that some DV-path or a queue exists that is still
- * considered confirmed.
- */
- struct GNUNET_SCHEDULER_Task *visibility_task;
- /**
- * Task scheduled to periodically retransmit FC messages (in
- * case one got lost).
- */
- struct GNUNET_SCHEDULER_Task *fc_retransmit_task;
- /**
- * Neighbour used by this virtual link, NULL if @e dv is used.
- */
- struct Neighbour *n;
- /**
- * Distance vector used by this virtual link, NULL if @e n is used.
- */
- struct DistanceVector *dv;
- /**
- * Sender timestamp of @e n_challenge, used to generate out-of-order
- * challenges (as sender's timestamps must be monotonically
- * increasing). FIXME: where do we need this?
- */
- struct GNUNET_TIME_Absolute n_challenge_time;
- /**
- * When did we last send a
- * #GNUNET_MESSAGE_TYPE_TRANSPORT_FLOW_CONTROL message?
- * Used to determine whether it is time to re-transmit the message.
- */
- struct GNUNET_TIME_Absolute last_fc_transmission;
- /**
- * Sender timestamp of the last
- * #GNUNET_MESSAGE_TYPE_TRANSPORT_FLOW_CONTROL message we have
- * received. Note that we do not persist this monotonic time as we
- * do not really have to worry about ancient flow control window
- * sizes after restarts.
- */
- struct GNUNET_TIME_Absolute last_fc_timestamp;
- /**
- * Expected RTT from the last FC transmission. (Zero if the last
- * attempt failed, but could theoretically be zero even on success.)
- */
- struct GNUNET_TIME_Relative last_fc_rtt;
- /**
- * Used to generate unique UUIDs for messages that are being
- * fragmented.
- */
- uint64_t message_uuid_ctr;
- /**
- * Memory allocated for this virtual link. Expresses how much RAM
- * we are willing to allocate to this virtual link. OPTIMIZE-ME:
- * Can be adapted to dedicate more RAM to links that need it, while
- * sticking to some overall RAM limit. For now, set to
- * #DEFAULT_WINDOW_SIZE.
- */
- uint64_t available_fc_window_size;
- /**
- * Memory actually used to buffer packets on this virtual link.
- * Expresses how much RAM we are currently using for virtual link.
- * Note that once CORE is done with a packet, we decrement the value
- * here.
- */
- uint64_t incoming_fc_window_size_ram;
- /**
- * Last flow control window size we provided to the other peer, in
- * bytes. We are allowing the other peer to send this
- * many bytes.
- */
- uint64_t incoming_fc_window_size;
- /**
- * How much of the window did the other peer successfully use (and
- * we already passed it on to CORE)? Must be below @e
- * incoming_fc_window_size. We should effectively signal the
- * other peer that the window is this much bigger at the next
- * opportunity / challenge.
- */
- uint64_t incoming_fc_window_size_used;
- /**
- * What is our current estimate on the message loss rate for the sender?
- * Based on the difference between how much the sender sent according
- * to the last #GNUNET_MESSAGE_TYPE_TRANSPORT_FLOW_CONTROL message
- * (@e outbound_sent field) and how much we actually received at that
- * time (@e incoming_fc_window_size_used). This delta is then
- * added onto the @e incoming_fc_window_size when determining the
- * @e outbound_window_size we send to the other peer. Initially zero.
- * May be negative if we (due to out-of-order delivery) actually received
- * more than the sender claims to have sent in its last FC message.
- */
- int64_t incoming_fc_window_size_loss;
- /**
- * Our current flow control window size in bytes. We
- * are allowed to transmit this many bytes to @a n.
- */
- uint64_t outbound_fc_window_size;
- /**
- * How much of our current flow control window size have we
- * used (in bytes). Must be below
- * @e outbound_fc_window_size.
- */
- uint64_t outbound_fc_window_size_used;
- /**
- * What is the most recent FC window the other peer sent us
- * in `outbound_window_size`? This is basically the window
- * size value the other peer has definitively received from
- * us. If it matches @e incoming_fc_window_size, we should
- * not send a FC message to increase the FC window. However,
- * we may still send an FC message to notify the other peer
- * that we received the other peer's FC message.
- */
- uint64_t last_outbound_window_size_received;
- /**
- * Generator for the sequence numbers of
- * #GNUNET_MESSAGE_TYPE_TRANSPORT_FLOW_CONTROL messages we send.
- */
- uint32_t fc_seq_gen;
- /**
- * Last sequence number of a
- * #GNUNET_MESSAGE_TYPE_TRANSPORT_FLOW_CONTROL message we have
- * received.
- */
- uint32_t last_fc_seq;
- /**
- * How many more messages can we send to CORE before we exhaust
- * the receive window of CORE for this peer? If this hits zero,
- * we must tell communicators to stop providing us more messages
- * for this peer. In fact, the window can go negative as we
- * have multiple communicators, so per communicator we can go
- * down by one into the negative range. Furthermore, we count
- * delivery per CORE client, so if we had multiple cores, that
- * might also cause a negative window size here (as one message
- * would decrement the window by one per CORE client).
- */
- int core_recv_window;
- };
- /**
- * Data structure kept when we are waiting for an acknowledgement.
- */
- struct PendingAcknowledgement
- {
- /**
- * If @e pm is non-NULL, this is the DLL in which this acknowledgement
- * is kept in relation to its pending message.
- */
- struct PendingAcknowledgement *next_pm;
- /**
- * If @e pm is non-NULL, this is the DLL in which this acknowledgement
- * is kept in relation to its pending message.
- */
- struct PendingAcknowledgement *prev_pm;
- /**
- * If @e queue is non-NULL, this is the DLL in which this acknowledgement
- * is kept in relation to the queue that was used to transmit the
- * @a pm.
- */
- struct PendingAcknowledgement *next_queue;
- /**
- * If @e queue is non-NULL, this is the DLL in which this acknowledgement
- * is kept in relation to the queue that was used to transmit the
- * @a pm.
- */
- struct PendingAcknowledgement *prev_queue;
- /**
- * If @e dvh is non-NULL, this is the DLL in which this acknowledgement
- * is kept in relation to the DVH that was used to transmit the
- * @a pm.
- */
- struct PendingAcknowledgement *next_dvh;
- /**
- * If @e dvh is non-NULL, this is the DLL in which this acknowledgement
- * is kept in relation to the DVH that was used to transmit the
- * @a pm.
- */
- struct PendingAcknowledgement *prev_dvh;
- /**
- * Pointers for the DLL of all pending acknowledgements.
- * This list is sorted by @e transmission time. If the list gets too
- * long, the oldest entries are discarded.
- */
- struct PendingAcknowledgement *next_pa;
- /**
- * Pointers for the DLL of all pending acknowledgements.
- * This list is sorted by @e transmission time. If the list gets too
- * long, the oldest entries are discarded.
- */
- struct PendingAcknowledgement *prev_pa;
- /**
- * Unique identifier for this transmission operation.
- */
- struct AcknowledgementUUIDP ack_uuid;
- /**
- * Message that was transmitted, may be NULL if the message was ACKed
- * via another channel.
- */
- struct PendingMessage *pm;
- /**
- * Distance vector path chosen for this transmission, NULL if transmission
- * was to a direct neighbour OR if the path was forgotten in the meantime.
- */
- struct DistanceVectorHop *dvh;
- /**
- * Queue used for transmission, NULL if the queue has been destroyed
- * (which may happen before we get an acknowledgement).
- */
- struct Queue *queue;
- /**
- * Time of the transmission, for RTT calculation.
- */
- struct GNUNET_TIME_Absolute transmission_time;
- /**
- * Number of bytes of the original message (to calculate bandwidth).
- */
- uint16_t message_size;
- };
- /**
- * One possible hop towards a DV target.
- */
- struct DistanceVectorHop
- {
- /**
- * Kept in a MDLL, sorted by @e timeout.
- */
- struct DistanceVectorHop *next_dv;
- /**
- * Kept in a MDLL, sorted by @e timeout.
- */
- struct DistanceVectorHop *prev_dv;
- /**
- * Kept in a MDLL.
- */
- struct DistanceVectorHop *next_neighbour;
- /**
- * Kept in a MDLL.
- */
- struct DistanceVectorHop *prev_neighbour;
- /**
- * Head of DLL of PAs that used our @a path.
- */
- struct PendingAcknowledgement *pa_head;
- /**
- * Tail of DLL of PAs that used our @a path.
- */
- struct PendingAcknowledgement *pa_tail;
- /**
- * What would be the next hop to @e target?
- */
- struct Neighbour *next_hop;
- /**
- * Distance vector entry this hop belongs with.
- */
- struct DistanceVector *dv;
- /**
- * Array of @e distance hops to the target, excluding @e next_hop.
- * NULL if the entire path is us to @e next_hop to `target`. Allocated
- * at the end of this struct. Excludes the target itself!
- */
- const struct GNUNET_PeerIdentity *path;
- /**
- * At what time do we forget about this path unless we see it again
- * while learning?
- */
- struct GNUNET_TIME_Absolute timeout;
- /**
- * For how long is the validation of this path considered
- * valid?
- * Set to ZERO if the path is learned by snooping on DV learn messages
- * initiated by other peers, and to the time at which we generated the
- * challenge for DV learn operations this peer initiated.
- */
- struct GNUNET_TIME_Absolute path_valid_until;
- /**
- * Performance data for this transmission possibility.
- */
- struct PerformanceData pd;
- /**
- * Number of hops in total to the `target` (excluding @e next_hop and `target`
- * itself). Thus 0 still means a distance of 2 hops (to @e next_hop and then
- * to `target`).
- */
- unsigned int distance;
- };
- /**
- * Entry in our #dv_routes table, representing a (set of) distance
- * vector routes to a particular peer.
- */
- struct DistanceVector
- {
- /**
- * To which peer is this a route?
- */
- struct GNUNET_PeerIdentity target;
- /**
- * Known paths to @e target.
- */
- struct DistanceVectorHop *dv_head;
- /**
- * Known paths to @e target.
- */
- struct DistanceVectorHop *dv_tail;
- /**
- * Task scheduled to purge expired paths from @e dv_head MDLL.
- */
- struct GNUNET_SCHEDULER_Task *timeout_task;
- /**
- * Do we have a confirmed working queue and are thus visible to
- * CORE? If so, this is the virtual link, otherwise NULL.
- */
- struct VirtualLink *vl;
- /**
- * Signature affirming @e ephemeral_key of type
- * #GNUNET_SIGNATURE_PURPOSE_TRANSPORT_EPHEMERAL
- */
- struct GNUNET_CRYPTO_EddsaSignature sender_sig;
- /**
- * How long is @e sender_sig valid
- */
- struct GNUNET_TIME_Absolute ephemeral_validity;
- /**
- * What time was @e sender_sig created
- */
- struct GNUNET_TIME_Absolute monotime;
- /**
- * Our ephemeral key.
- */
- struct GNUNET_CRYPTO_EcdhePublicKey ephemeral_key;
- /**
- * Our private ephemeral key.
- */
- struct GNUNET_CRYPTO_EcdhePrivateKey private_key;
- };
- /**
- * Entry identifying transmission in one of our `struct
- * Queue` which still awaits an ACK. This is used to
- * ensure we do not overwhelm a communicator and limit the number of
- * messages outstanding per communicator (say in case communicator is
- * CPU bound) and per queue (in case bandwidth allocation exceeds
- * what the communicator can actually provide towards a particular
- * peer/target).
- */
- struct QueueEntry
- {
- /**
- * Kept as a DLL.
- */
- struct QueueEntry *next;
- /**
- * Kept as a DLL.
- */
- struct QueueEntry *prev;
- /**
- * Queue this entry is queued with.
- */
- struct Queue *queue;
- /**
- * Pending message this entry is for, or NULL for none.
- */
- struct PendingMessage *pm;
- /**
- * Message ID used for this message with the queue used for transmission.
- */
- uint64_t mid;
- };
- /**
- * A queue is a message queue provided by a communicator
- * via which we can reach a particular neighbour.
- */
- struct Queue
- {
- /**
- * Kept in a MDLL.
- */
- struct Queue *next_neighbour;
- /**
- * Kept in a MDLL.
- */
- struct Queue *prev_neighbour;
- /**
- * Kept in a MDLL.
- */
- struct Queue *prev_client;
- /**
- * Kept in a MDLL.
- */
- struct Queue *next_client;
- /**
- * Head of DLL of PAs that used this queue.
- */
- struct PendingAcknowledgement *pa_head;
- /**
- * Tail of DLL of PAs that used this queue.
- */
- struct PendingAcknowledgement *pa_tail;
- /**
- * Head of DLL of unacked transmission requests.
- */
- struct QueueEntry *queue_head;
- /**
- * End of DLL of unacked transmission requests.
- */
- struct QueueEntry *queue_tail;
- /**
- * Which neighbour is this queue for?
- */
- struct Neighbour *neighbour;
- /**
- * Which communicator offers this queue?
- */
- struct TransportClient *tc;
- /**
- * Address served by the queue.
- */
- const char *address;
- /**
- * Task scheduled for the time when this queue can (likely) transmit the
- * next message.
- */
- struct GNUNET_SCHEDULER_Task *transmit_task;
- /**
- * How long do *we* consider this @e address to be valid? In the past or
- * zero if we have not yet validated it. Can be updated based on
- * challenge-response validations (via address validation logic), or when we
- * receive ACKs that we can definitively map to transmissions via this
- * queue.
- */
- struct GNUNET_TIME_Absolute validated_until;
- /**
- * Performance data for this queue.
- */
- struct PerformanceData pd;
- /**
- * Message ID generator for transmissions on this queue to the
- * communicator.
- */
- uint64_t mid_gen;
- /**
- * Unique identifier of this queue with the communicator.
- */
- uint32_t qid;
- /**
- * Maximum transmission unit supported by this queue.
- */
- uint32_t mtu;
- /**
- * Messages pending.
- */
- uint32_t num_msg_pending;
- /**
- * Bytes pending.
- */
- uint32_t num_bytes_pending;
- /**
- * Length of the DLL starting at @e queue_head.
- */
- unsigned int queue_length;
- /**
- * Network type offered by this queue.
- */
- enum GNUNET_NetworkType nt;
- /**
- * Connection status for this queue.
- */
- enum GNUNET_TRANSPORT_ConnectionStatus cs;
- /**
- * Set to #GNUNET_YES if this queue is idle waiting for some
- * virtual link to give it a pending message.
- */
- int idle;
- };
- /**
- * Information we keep for a message that we are reassembling.
- */
- struct ReassemblyContext
- {
- /**
- * Original message ID for of the message that all the fragments
- * belong to.
- */
- struct MessageUUIDP msg_uuid;
- /**
- * Which neighbour is this context for?
- */
- struct Neighbour *neighbour;
- /**
- * Entry in the reassembly heap (sorted by expiration).
- */
- struct GNUNET_CONTAINER_HeapNode *hn;
- /**
- * Bitfield with @e msg_size bits representing the positions
- * where we have received fragments. When we receive a fragment,
- * we check the bits in @e bitfield before incrementing @e msg_missing.
- *
- * Allocated after the reassembled message.
- */
- uint8_t *bitfield;
- /**
- * At what time will we give up reassembly of this message?
- */
- struct GNUNET_TIME_Absolute reassembly_timeout;
- /**
- * Time we received the last fragment. @e avg_ack_delay must be
- * incremented by now - @e last_frag multiplied by @e num_acks.
- */
- struct GNUNET_TIME_Absolute last_frag;
- /**
- * How big is the message we are reassembling in total?
- */
- uint16_t msg_size;
- /**
- * How many bytes of the message are still missing? Defragmentation
- * is complete when @e msg_missing == 0.
- */
- uint16_t msg_missing;
- /* Followed by @e msg_size bytes of the (partially) defragmented original
- * message */
- /* Followed by @e bitfield data */
- };
- /**
- * A neighbour that at least one communicator is connected to.
- */
- struct Neighbour
- {
- /**
- * Which peer is this about?
- */
- struct GNUNET_PeerIdentity pid;
- /**
- * Map with `struct ReassemblyContext` structs for fragments under
- * reassembly. May be NULL if we currently have no fragments from
- * this @e pid (lazy initialization).
- */
- struct GNUNET_CONTAINER_MultiHashMap32 *reassembly_map;
- /**
- * Heap with `struct ReassemblyContext` structs for fragments under
- * reassembly. May be NULL if we currently have no fragments from
- * this @e pid (lazy initialization).
- */
- struct GNUNET_CONTAINER_Heap *reassembly_heap;
- /**
- * Task to free old entries from the @e reassembly_heap and @e reassembly_map.
- */
- struct GNUNET_SCHEDULER_Task *reassembly_timeout_task;
- /**
- * Head of MDLL of DV hops that have this neighbour as next hop. Must be
- * purged if this neighbour goes down.
- */
- struct DistanceVectorHop *dv_head;
- /**
- * Tail of MDLL of DV hops that have this neighbour as next hop. Must be
- * purged if this neighbour goes down.
- */
- struct DistanceVectorHop *dv_tail;
- /**
- * Head of DLL of queues to this peer.
- */
- struct Queue *queue_head;
- /**
- * Tail of DLL of queues to this peer.
- */
- struct Queue *queue_tail;
- /**
- * Handle for an operation to fetch @e last_dv_learn_monotime information from
- * the PEERSTORE, or NULL.
- */
- struct GNUNET_PEERSTORE_IterateContext *get;
- /**
- * Handle to a PEERSTORE store operation to store this @e pid's @e
- * @e last_dv_learn_monotime. NULL if no PEERSTORE operation is pending.
- */
- struct GNUNET_PEERSTORE_StoreContext *sc;
- /**
- * Do we have a confirmed working queue and are thus visible to
- * CORE? If so, this is the virtual link, otherwise NULL.
- */
- struct VirtualLink *vl;
- /**
- * Latest DVLearn monotonic time seen from this peer. Initialized only
- * if @e dl_monotime_available is #GNUNET_YES.
- */
- struct GNUNET_TIME_Absolute last_dv_learn_monotime;
- /**
- * Do we have the lastest value for @e last_dv_learn_monotime from
- * PEERSTORE yet, or are we still waiting for a reply of PEERSTORE?
- */
- int dv_monotime_available;
- };
- /**
- * Another peer attempted to talk to us, we should try to establish
- * a connection in the other direction.
- */
- struct IncomingRequest
- {
- /**
- * Kept in a DLL.
- */
- struct IncomingRequest *next;
- /**
- * Kept in a DLL.
- */
- struct IncomingRequest *prev;
- /**
- * Handle for watching the peerstore for HELLOs for this peer.
- */
- struct GNUNET_PEERSTORE_WatchContext *wc;
- /**
- * Which peer is this about?
- */
- struct GNUNET_PeerIdentity pid;
- };
- /**
- * A peer that an application (client) would like us to talk to directly.
- */
- struct PeerRequest
- {
- /**
- * Which peer is this about?
- */
- struct GNUNET_PeerIdentity pid;
- /**
- * Client responsible for the request.
- */
- struct TransportClient *tc;
- /**
- * Handle for watching the peerstore for HELLOs for this peer.
- */
- struct GNUNET_PEERSTORE_WatchContext *wc;
- /**
- * What kind of performance preference does this @e tc have?
- *
- * TODO: use this!
- */
- enum GNUNET_MQ_PriorityPreferences pk;
- /**
- * How much bandwidth would this @e tc like to see?
- */
- struct GNUNET_BANDWIDTH_Value32NBO bw;
- };
- /**
- * Types of different pending messages.
- */
- enum PendingMessageType
- {
- /**
- * Ordinary message received from the CORE service.
- */
- PMT_CORE = 0,
- /**
- * Fragment box.
- */
- PMT_FRAGMENT_BOX = 1,
- /**
- * Reliability box.
- */
- PMT_RELIABILITY_BOX = 2,
- /**
- * Pending message created during #forward_dv_box().
- */
- PMT_DV_BOX = 3
- };
- /**
- * Transmission request that is awaiting delivery. The original
- * transmission requests from CORE may be too big for some queues.
- * In this case, a *tree* of fragments is created. At each
- * level of the tree, fragments are kept in a DLL ordered by which
- * fragment should be sent next (at the head). The tree is searched
- * top-down, with the original message at the root.
- *
- * To select a node for transmission, first it is checked if the
- * current node's message fits with the MTU. If it does not, we
- * either calculate the next fragment (based on @e frag_off) from the
- * current node, or, if all fragments have already been created,
- * descend to the @e head_frag. Even though the node was already
- * fragmented, the fragment may be too big if the fragment was
- * generated for a queue with a larger MTU. In this case, the node
- * may be fragmented again, thus creating a tree.
- *
- * When acknowledgements for fragments are received, the tree
- * must be pruned, removing those parts that were already
- * acknowledged. When fragments are sent over a reliable
- * channel, they can be immediately removed.
- *
- * If a message is ever fragmented, then the original "full" message
- * is never again transmitted (even if it fits below the MTU), and
- * only (remaining) fragments are sent.
- */
- struct PendingMessage
- {
- /**
- * Kept in a MDLL of messages for this @a vl.
- */
- struct PendingMessage *next_vl;
- /**
- * Kept in a MDLL of messages for this @a vl.
- */
- struct PendingMessage *prev_vl;
- /**
- * Kept in a MDLL of messages from this @a client (if @e pmt is #PMT_CORE)
- */
- struct PendingMessage *next_client;
- /**
- * Kept in a MDLL of messages from this @a client (if @e pmt is #PMT_CORE)
- */
- struct PendingMessage *prev_client;
- /**
- * Kept in a MDLL of messages from this @a cpm (if @e pmt is
- * #PMT_FRAGMENT_BOx)
- */
- struct PendingMessage *next_frag;
- /**
- * Kept in a MDLL of messages from this @a cpm (if @e pmt is
- * #PMT_FRAGMENT_BOX)
- */
- struct PendingMessage *prev_frag;
- /**
- * Head of DLL of PAs for this pending message.
- */
- struct PendingAcknowledgement *pa_head;
- /**
- * Tail of DLL of PAs for this pending message.
- */
- struct PendingAcknowledgement *pa_tail;
- /**
- * This message, reliability *or* DV-boxed. Only possibly available
- * if @e pmt is #PMT_CORE.
- */
- struct PendingMessage *bpm;
- /**
- * Target of the request (always the ultimate destination!).
- */
- struct VirtualLink *vl;
- /**
- * Set to non-NULL value if this message is currently being given to a
- * communicator and we are awaiting that communicator's acknowledgement.
- * Note that we must not retransmit a pending message while we're still
- * in the process of giving it to a communicator. If a pending message
- * is free'd while this entry is non-NULL, the @e qe reference to us
- * should simply be set to NULL.
- */
- struct QueueEntry *qe;
- /**
- * Client that issued the transmission request, if @e pmt is #PMT_CORE.
- */
- struct TransportClient *client;
- /**
- * Head of a MDLL of fragments created for this core message.
- */
- struct PendingMessage *head_frag;
- /**
- * Tail of a MDLL of fragments created for this core message.
- */
- struct PendingMessage *tail_frag;
- /**
- * Our parent in the fragmentation tree.
- */
- struct PendingMessage *frag_parent;
- /**
- * At what time should we give up on the transmission (and no longer retry)?
- */
- struct GNUNET_TIME_Absolute timeout;
- /**
- * What is the earliest time for us to retry transmission of this message?
- */
- struct GNUNET_TIME_Absolute next_attempt;
- /**
- * UUID to use for this message (used for reassembly of fragments, only
- * initialized if @e msg_uuid_set is #GNUNET_YES).
- */
- struct MessageUUIDP msg_uuid;
- /**
- * UUID we use to identify this message in our logs.
- * Generated by incrementing the "logging_uuid_gen".
- */
- unsigned long long logging_uuid;
- /**
- * Type of the pending message.
- */
- enum PendingMessageType pmt;
- /**
- * Preferences for this message.
- * TODO: actually use this!
- */
- enum GNUNET_MQ_PriorityPreferences prefs;
- /**
- * Size of the original message.
- */
- uint16_t bytes_msg;
- /**
- * Offset at which we should generate the next fragment.
- */
- uint16_t frag_off;
- /**
- * #GNUNET_YES once @e msg_uuid was initialized
- */
- int16_t msg_uuid_set;
- /* Followed by @e bytes_msg to transmit */
- };
- /**
- * Acknowledgement payload.
- */
- struct TransportCummulativeAckPayload
- {
- /**
- * When did we receive the message we are ACKing? Used to calculate
- * the delay we introduced by cummulating ACKs.
- */
- struct GNUNET_TIME_Absolute receive_time;
- /**
- * UUID of a message being acknowledged.
- */
- struct AcknowledgementUUIDP ack_uuid;
- };
- /**
- * Data structure in which we track acknowledgements still to
- * be sent to the
- */
- struct AcknowledgementCummulator
- {
- /**
- * Target peer for which we are accumulating ACKs here.
- */
- struct GNUNET_PeerIdentity target;
- /**
- * ACK data being accumulated. Only @e num_acks slots are valid.
- */
- struct TransportCummulativeAckPayload ack_uuids[MAX_CUMMULATIVE_ACKS];
- /**
- * Task scheduled either to transmit the cummulative ACK message,
- * or to clean up this data structure after extended periods of
- * inactivity (if @e num_acks is zero).
- */
- struct GNUNET_SCHEDULER_Task *task;
- /**
- * When is @e task run (only used if @e num_acks is non-zero)?
- */
- struct GNUNET_TIME_Absolute min_transmission_time;
- /**
- * Counter to produce the `ack_counter` in the `struct
- * TransportReliabilityAckMessage`. Allows the receiver to detect
- * lost ACK messages. Incremented by @e num_acks upon transmission.
- */
- uint32_t ack_counter;
- /**
- * Number of entries used in @e ack_uuids. Reset to 0 upon transmission.
- */
- unsigned int num_acks;
- };
- /**
- * One of the addresses of this peer.
- */
- struct AddressListEntry
- {
- /**
- * Kept in a DLL.
- */
- struct AddressListEntry *next;
- /**
- * Kept in a DLL.
- */
- struct AddressListEntry *prev;
- /**
- * Which communicator provides this address?
- */
- struct TransportClient *tc;
- /**
- * The actual address.
- */
- const char *address;
- /**
- * Current context for storing this address in the peerstore.
- */
- struct GNUNET_PEERSTORE_StoreContext *sc;
- /**
- * Task to periodically do @e st operation.
- */
- struct GNUNET_SCHEDULER_Task *st;
- /**
- * What is a typical lifetime the communicator expects this
- * address to have? (Always from now.)
- */
- struct GNUNET_TIME_Relative expiration;
- /**
- * Address identifier used by the communicator.
- */
- uint32_t aid;
- /**
- * Network type offered by this address.
- */
- enum GNUNET_NetworkType nt;
- };
- /**
- * Client connected to the transport service.
- */
- struct TransportClient
- {
- /**
- * Kept in a DLL.
- */
- struct TransportClient *next;
- /**
- * Kept in a DLL.
- */
- struct TransportClient *prev;
- /**
- * Handle to the client.
- */
- struct GNUNET_SERVICE_Client *client;
- /**
- * Message queue to the client.
- */
- struct GNUNET_MQ_Handle *mq;
- /**
- * What type of client is this?
- */
- enum ClientType type;
- union
- {
- /**
- * Information for @e type #CT_CORE.
- */
- struct
- {
- /**
- * Head of list of messages pending for this client, sorted by
- * transmission time ("next_attempt" + possibly internal prioritization).
- */
- struct PendingMessage *pending_msg_head;
- /**
- * Tail of list of messages pending for this client.
- */
- struct PendingMessage *pending_msg_tail;
- } core;
- /**
- * Information for @e type #CT_MONITOR.
- */
- struct
- {
- /**
- * Peer identity to monitor the addresses of.
- * Zero to monitor all neighbours. Valid if
- * @e type is #CT_MONITOR.
- */
- struct GNUNET_PeerIdentity peer;
- /**
- * Is this a one-shot monitor?
- */
- int one_shot;
- } monitor;
- /**
- * Information for @e type #CT_COMMUNICATOR.
- */
- struct
- {
- /**
- * If @e type is #CT_COMMUNICATOR, this communicator
- * supports communicating using these addresses.
- */
- char *address_prefix;
- /**
- * Head of DLL of queues offered by this communicator.
- */
- struct Queue *queue_head;
- /**
- * Tail of DLL of queues offered by this communicator.
- */
- struct Queue *queue_tail;
- /**
- * Head of list of the addresses of this peer offered by this
- * communicator.
- */
- struct AddressListEntry *addr_head;
- /**
- * Tail of list of the addresses of this peer offered by this
- * communicator.
- */
- struct AddressListEntry *addr_tail;
- /**
- * Number of queue entries in all queues to this communicator. Used
- * throttle sending to a communicator if we see that the communicator
- * is globally unable to keep up.
- */
- unsigned int total_queue_length;
- /**
- * Characteristics of this communicator.
- */
- enum GNUNET_TRANSPORT_CommunicatorCharacteristics cc;
- } communicator;
- /**
- * Information for @e type #CT_APPLICATION
- */
- struct
- {
- /**
- * Map of requests for peers the given client application would like to
- * see connections for. Maps from PIDs to `struct PeerRequest`.
- */
- struct GNUNET_CONTAINER_MultiPeerMap *requests;
- } application;
- } details;
- };
- /**
- * State we keep for validation activities. Each of these
- * is both in the #validation_heap and the #validation_map.
- */
- struct ValidationState
- {
- /**
- * For which peer is @a address to be validated (or possibly valid)?
- * Serves as key in the #validation_map.
- */
- struct GNUNET_PeerIdentity pid;
- /**
- * How long did the peer claim this @e address to be valid? Capped at
- * minimum of #MAX_ADDRESS_VALID_UNTIL relative to the time where we last
- * were told about the address and the value claimed by the other peer at
- * that time. May be updated similarly when validation succeeds.
- */
- struct GNUNET_TIME_Absolute valid_until;
- /**
- * How long do *we* consider this @e address to be valid?
- * In the past or zero if we have not yet validated it.
- */
- struct GNUNET_TIME_Absolute validated_until;
- /**
- * When did we FIRST use the current @e challenge in a message?
- * Used to sanity-check @code{origin_time} in the response when
- * calculating the RTT. If the @code{origin_time} is not in
- * the expected range, the response is discarded as malicious.
- */
- struct GNUNET_TIME_Absolute first_challenge_use;
- /**
- * When did we LAST use the current @e challenge in a message?
- * Used to sanity-check @code{origin_time} in the response when
- * calculating the RTT. If the @code{origin_time} is not in
- * the expected range, the response is discarded as malicious.
- */
- struct GNUNET_TIME_Absolute last_challenge_use;
- /**
- * Next time we will send the @e challenge to the peer, if this time is past
- * @e valid_until, this validation state is released at this time. If the
- * address is valid, @e next_challenge is set to @e validated_until MINUS @e
- * validation_delay * #VALIDATION_RTT_BUFFER_FACTOR, such that we will try
- * to re-validate before the validity actually expires.
- */
- struct GNUNET_TIME_Absolute next_challenge;
- /**
- * Current backoff factor we're applying for sending the @a challenge.
- * Reset to 0 if the @a challenge is confirmed upon validation.
- * Reduced to minimum of #FAST_VALIDATION_CHALLENGE_FREQ and half of the
- * existing value if we receive an unvalidated address again over
- * another channel (and thus should consider the information "fresh").
- * Maximum is #MAX_VALIDATION_CHALLENGE_FREQ.
- */
- struct GNUNET_TIME_Relative challenge_backoff;
- /**
- * Initially set to "forever". Once @e validated_until is set, this value is
- * set to the RTT that tells us how long it took to receive the validation.
- */
- struct GNUNET_TIME_Relative validation_rtt;
- /**
- * The challenge we sent to the peer to get it to validate the address. Note
- * that we rotate the challenge whenever we update @e validated_until to
- * avoid attacks where a peer simply replays an old challenge in the future.
- * (We must not rotate more often as otherwise we may discard valid answers
- * due to packet losses, latency and reorderings on the network).
- */
- struct ChallengeNonceP challenge;
- /**
- * Claimed address of the peer.
- */
- char *address;
- /**
- * Entry in the #validation_heap, which is sorted by @e next_challenge. The
- * heap is used to figure out when the next validation activity should be
- * run.
- */
- struct GNUNET_CONTAINER_HeapNode *hn;
- /**
- * Handle to a PEERSTORE store operation for this @e address. NULL if
- * no PEERSTORE operation is pending.
- */
- struct GNUNET_PEERSTORE_StoreContext *sc;
- /**
- * Self-imposed limit on the previous flow control window. (May be zero,
- * if we never used data from the previous window or are establishing the
- * connection for the first time).
- */
- uint32_t last_window_consum_limit;
- /**
- * We are technically ready to send the challenge, but we are waiting for
- * the respective queue to become available for transmission.
- */
- int awaiting_queue;
- };
- /**
- * A Backtalker is a peer sending us backchannel messages. We use this
- * struct to detect monotonic time violations, cache ephemeral key
- * material (to avoid repeatedly checking signatures), and to synchronize
- * monotonic time with the PEERSTORE.
- */
- struct Backtalker
- {
- /**
- * Peer this is about.
- */
- struct GNUNET_PeerIdentity pid;
- /**
- * Last (valid) monotonic time received from this sender.
- */
- struct GNUNET_TIME_Absolute monotonic_time;
- /**
- * When will this entry time out?
- */
- struct GNUNET_TIME_Absolute timeout;
- /**
- * Last (valid) ephemeral key received from this sender.
- */
- struct GNUNET_CRYPTO_EcdhePublicKey last_ephemeral;
- /**
- * Task associated with this backtalker. Can be for timeout,
- * or other asynchronous operations.
- */
- struct GNUNET_SCHEDULER_Task *task;
- /**
- * Communicator context waiting on this backchannel's @e get, or NULL.
- */
- struct CommunicatorMessageContext *cmc;
- /**
- * Handle for an operation to fetch @e monotonic_time information from the
- * PEERSTORE, or NULL.
- */
- struct GNUNET_PEERSTORE_IterateContext *get;
- /**
- * Handle to a PEERSTORE store operation for this @e pid's @e
- * monotonic_time. NULL if no PEERSTORE operation is pending.
- */
- struct GNUNET_PEERSTORE_StoreContext *sc;
- /**
- * Number of bytes of the original message body that follows after this
- * struct.
- */
- size_t body_size;
- };
- /**
- * Head of linked list of all clients to this service.
- */
- static struct TransportClient *clients_head;
- /**
- * Tail of linked list of all clients to this service.
- */
- static struct TransportClient *clients_tail;
- /**
- * Statistics handle.
- */
- static struct GNUNET_STATISTICS_Handle *GST_stats;
- /**
- * Configuration handle.
- */
- static const struct GNUNET_CONFIGURATION_Handle *GST_cfg;
- /**
- * Our public key.
- */
- static struct GNUNET_PeerIdentity GST_my_identity;
- /**
- * Our private key.
- */
- static struct GNUNET_CRYPTO_EddsaPrivateKey *GST_my_private_key;
- /**
- * Map from PIDs to `struct Neighbour` entries. A peer is
- * a neighbour if we have an MQ to it from some communicator.
- */
- static struct GNUNET_CONTAINER_MultiPeerMap *neighbours;
- /**
- * Map from PIDs to `struct Backtalker` entries. A peer is
- * a backtalker if it recently send us backchannel messages.
- */
- static struct GNUNET_CONTAINER_MultiPeerMap *backtalkers;
- /**
- * Map from PIDs to `struct AcknowledgementCummulator`s.
- * Here we track the cummulative ACKs for transmission.
- */
- static struct GNUNET_CONTAINER_MultiPeerMap *ack_cummulators;
- /**
- * Map of pending acknowledgements, mapping `struct AcknowledgementUUID` to
- * a `struct PendingAcknowledgement`.
- */
- static struct GNUNET_CONTAINER_MultiUuidmap *pending_acks;
- /**
- * Map from PIDs to `struct DistanceVector` entries describing
- * known paths to the peer.
- */
- static struct GNUNET_CONTAINER_MultiPeerMap *dv_routes;
- /**
- * Map from PIDs to `struct ValidationState` entries describing
- * addresses we are aware of and their validity state.
- */
- static struct GNUNET_CONTAINER_MultiPeerMap *validation_map;
- /**
- * Map from PIDs to `struct VirtualLink` entries describing
- * links CORE knows to exist.
- */
- static struct GNUNET_CONTAINER_MultiPeerMap *links;
- /**
- * Map from challenges to `struct LearnLaunchEntry` values.
- */
- static struct GNUNET_CONTAINER_MultiShortmap *dvlearn_map;
- /**
- * Head of a DLL sorted by launch time.
- */
- static struct LearnLaunchEntry *lle_head;
- /**
- * Tail of a DLL sorted by launch time.
- */
- static struct LearnLaunchEntry *lle_tail;
- /**
- * MIN Heap sorted by "next_challenge" to `struct ValidationState` entries
- * sorting addresses we are aware of by when we should next try to (re)validate
- * (or expire) them.
- */
- static struct GNUNET_CONTAINER_Heap *validation_heap;
- /**
- * Database for peer's HELLOs.
- */
- static struct GNUNET_PEERSTORE_Handle *peerstore;
- /**
- * Task run to initiate DV learning.
- */
- static struct GNUNET_SCHEDULER_Task *dvlearn_task;
- /**
- * Task to run address validation.
- */
- static struct GNUNET_SCHEDULER_Task *validation_task;
- /**
- * The most recent PA we have created, head of DLL.
- * The length of the DLL is kept in #pa_count.
- */
- static struct PendingAcknowledgement *pa_head;
- /**
- * The oldest PA we have created, tail of DLL.
- * The length of the DLL is kept in #pa_count.
- */
- static struct PendingAcknowledgement *pa_tail;
- /**
- * List of incomming connections where we are trying
- * to get a connection back established. Length
- * kept in #ir_total.
- */
- static struct IncomingRequest *ir_head;
- /**
- * Tail of DLL starting at #ir_head.
- */
- static struct IncomingRequest *ir_tail;
- /**
- * Length of the DLL starting at #ir_head.
- */
- static unsigned int ir_total;
- /**
- * Generator of `logging_uuid` in `struct PendingMessage`.
- */
- static unsigned long long logging_uuid_gen;
- /**
- * Number of entries in the #pa_head/#pa_tail DLL. Used to
- * limit the size of the data structure.
- */
- static unsigned int pa_count;
- /**
- * Monotonic time we use for HELLOs generated at this time. TODO: we
- * should increase this value from time to time (i.e. whenever a
- * `struct AddressListEntry` actually expires), but IF we do this, we
- * must also update *all* (remaining) addresses in the PEERSTORE at
- * that time! (So for now only increased when the peer is restarted,
- * which hopefully roughly matches whenever our addresses change.)
- */
- static struct GNUNET_TIME_Absolute hello_mono_time;
- /**
- * Get an offset into the transmission history buffer for `struct
- * PerformanceData`. Note that the caller must perform the required
- * modulo #GOODPUT_AGING_SLOTS operation before indexing into the
- * array!
- *
- * An 'age' lasts 15 minute slots.
- *
- * @return current age of the world
- */
- static unsigned int
- get_age ()
- {
- struct GNUNET_TIME_Absolute now;
- now = GNUNET_TIME_absolute_get ();
- return now.abs_value_us / GNUNET_TIME_UNIT_MINUTES.rel_value_us / 15;
- }
- /**
- * Release @a ir data structure.
- *
- * @param ir data structure to release
- */
- static void
- free_incoming_request (struct IncomingRequest *ir)
- {
- GNUNET_CONTAINER_DLL_remove (ir_head, ir_tail, ir);
- GNUNET_assert (ir_total > 0);
- ir_total--;
- GNUNET_PEERSTORE_watch_cancel (ir->wc);
- GNUNET_free (ir);
- }
- /**
- * Release @a pa data structure.
- *
- * @param pa data structure to release
- */
- static void
- free_pending_acknowledgement (struct PendingAcknowledgement *pa)
- {
- struct Queue *q = pa->queue;
- struct PendingMessage *pm = pa->pm;
- struct DistanceVectorHop *dvh = pa->dvh;
- GNUNET_CONTAINER_MDLL_remove (pa, pa_head, pa_tail, pa);
- pa_count--;
- if (NULL != q)
- {
- GNUNET_CONTAINER_MDLL_remove (queue, q->pa_head, q->pa_tail, pa);
- pa->queue = NULL;
- }
- if (NULL != pm)
- {
- GNUNET_CONTAINER_MDLL_remove (pm, pm->pa_head, pm->pa_tail, pa);
- pa->pm = NULL;
- }
- if (NULL != dvh)
- {
- GNUNET_CONTAINER_MDLL_remove (dvh, dvh->pa_head, dvh->pa_tail, pa);
- pa->queue = NULL;
- }
- GNUNET_assert (GNUNET_YES ==
- GNUNET_CONTAINER_multiuuidmap_remove (pending_acks,
- &pa->ack_uuid.value,
- pa));
- GNUNET_free (pa);
- }
- /**
- * Free fragment tree below @e root, excluding @e root itself.
- * FIXME: this does NOT seem to have the intended semantics
- * based on how this is called. Seems we generally DO expect
- * @a root to be free'ed itself as well!
- *
- * @param root root of the tree to free
- */
- static void
- free_fragment_tree (struct PendingMessage *root)
- {
- struct PendingMessage *frag;
- while (NULL != (frag = root->head_frag))
- {
- struct PendingAcknowledgement *pa;
- free_fragment_tree (frag);
- while (NULL != (pa = frag->pa_head))
- {
- GNUNET_CONTAINER_MDLL_remove (pm, frag->pa_head, frag->pa_tail, pa);
- pa->pm = NULL;
- }
- GNUNET_CONTAINER_MDLL_remove (frag, root->head_frag, root->tail_frag, frag);
- GNUNET_free (frag);
- }
- }
- /**
- * Release memory associated with @a pm and remove @a pm from associated
- * data structures. @a pm must be a top-level pending message and not
- * a fragment in the tree. The entire tree is freed (if applicable).
- *
- * @param pm the pending message to free
- */
- static void
- free_pending_message (struct PendingMessage *pm)
- {
- struct TransportClient *tc = pm->client;
- struct VirtualLink *vl = pm->vl;
- struct PendingAcknowledgement *pa;
- if (NULL != tc)
- {
- GNUNET_CONTAINER_MDLL_remove (client,
- tc->details.core.pending_msg_head,
- tc->details.core.pending_msg_tail,
- pm);
- }
- if (NULL != vl)
- {
- GNUNET_CONTAINER_MDLL_remove (vl,
- vl->pending_msg_head,
- vl->pending_msg_tail,
- pm);
- }
- while (NULL != (pa = pm->pa_head))
- {
- GNUNET_CONTAINER_MDLL_remove (pm, pm->pa_head, pm->pa_tail, pa);
- pa->pm = NULL;
- }
- free_fragment_tree (pm);
- if (NULL != pm->qe)
- {
- GNUNET_assert (pm == pm->qe->pm);
- pm->qe->pm = NULL;
- }
- if (NULL != pm->bpm)
- {
- free_fragment_tree (pm->bpm);
- GNUNET_free (pm->bpm);
- }
- GNUNET_free (pm);
- }
- /**
- * Free virtual link.
- *
- * @param vl link data to free
- */
- static void
- free_virtual_link (struct VirtualLink *vl)
- {
- struct PendingMessage *pm;
- struct CoreSentContext *csc;
- while (NULL != (pm = vl->pending_msg_head))
- free_pending_message (pm);
- GNUNET_assert (GNUNET_YES ==
- GNUNET_CONTAINER_multipeermap_remove (links, &vl->target, vl));
- if (NULL != vl->visibility_task)
- {
- GNUNET_SCHEDULER_cancel (vl->visibility_task);
- vl->visibility_task = NULL;
- }
- if (NULL != vl->fc_retransmit_task)
- {
- GNUNET_SCHEDULER_cancel (vl->fc_retransmit_task);
- vl->fc_retransmit_task = NULL;
- }
- while (NULL != (csc = vl->csc_head))
- {
- GNUNET_CONTAINER_DLL_remove (vl->csc_head, vl->csc_tail, csc);
- GNUNET_assert (vl == csc->vl);
- csc->vl = NULL;
- }
- GNUNET_break (NULL == vl->n);
- GNUNET_break (NULL == vl->dv);
- GNUNET_free (vl);
- }
- /**
- * Free validation state.
- *
- * @param vs validation state to free
- */
- static void
- free_validation_state (struct ValidationState *vs)
- {
- GNUNET_assert (
- GNUNET_YES ==
- GNUNET_CONTAINER_multipeermap_remove (validation_map, &vs->pid, vs));
- GNUNET_CONTAINER_heap_remove_node (vs->hn);
- vs->hn = NULL;
- if (NULL != vs->sc)
- {
- GNUNET_PEERSTORE_store_cancel (vs->sc);
- vs->sc = NULL;
- }
- GNUNET_free (vs->address);
- GNUNET_free (vs);
- }
- /**
- * Lookup neighbour for peer @a pid.
- *
- * @param pid neighbour to look for
- * @return NULL if we do not have this peer as a neighbour
- */
- static struct Neighbour *
- lookup_neighbour (const struct GNUNET_PeerIdentity *pid)
- {
- return GNUNET_CONTAINER_multipeermap_get (neighbours, pid);
- }
- /**
- * Lookup virtual link for peer @a pid.
- *
- * @param pid virtual link to look for
- * @return NULL if we do not have this peer as a virtual link
- */
- static struct VirtualLink *
- lookup_virtual_link (const struct GNUNET_PeerIdentity *pid)
- {
- return GNUNET_CONTAINER_multipeermap_get (links, pid);
- }
- /**
- * Details about what to notify monitors about.
- */
- struct MonitorEvent
- {
- /**
- * @deprecated To be discussed if we keep these...
- */
- struct GNUNET_TIME_Absolute last_validation;
- struct GNUNET_TIME_Absolute valid_until;
- struct GNUNET_TIME_Absolute next_validation;
- /**
- * Current round-trip time estimate.
- */
- struct GNUNET_TIME_Relative rtt;
- /**
- * Connection status.
- */
- enum GNUNET_TRANSPORT_ConnectionStatus cs;
- /**
- * Messages pending.
- */
- uint32_t num_msg_pending;
- /**
- * Bytes pending.
- */
- uint32_t num_bytes_pending;
- };
- /**
- * Free a @dvh. Callers MAY want to check if this was the last path to the
- * `target`, and if so call #free_dv_route to also free the associated DV
- * entry in #dv_routes (if not, the associated scheduler job should eventually
- * take care of it).
- *
- * @param dvh hop to free
- */
- static void
- free_distance_vector_hop (struct DistanceVectorHop *dvh)
- {
- struct Neighbour *n = dvh->next_hop;
- struct DistanceVector *dv = dvh->dv;
- struct PendingAcknowledgement *pa;
- while (NULL != (pa = dvh->pa_head))
- {
- GNUNET_CONTAINER_MDLL_remove (dvh, dvh->pa_head, dvh->pa_tail, pa);
- pa->dvh = NULL;
- }
- GNUNET_CONTAINER_MDLL_remove (neighbour, n->dv_head, n->dv_tail, dvh);
- GNUNET_CONTAINER_MDLL_remove (dv, dv->dv_head, dv->dv_tail, dvh);
- GNUNET_free (dvh);
- }
- /**
- * Task run to check whether the hops of the @a cls still
- * are validated, or if we need to core about disconnection.
- *
- * @param cls a `struct VirtualLink`
- */
- static void
- check_link_down (void *cls);
- /**
- * Send message to CORE clients that we lost a connection.
- *
- * @param pid peer the connection was for
- */
- static void
- cores_send_disconnect_info (const struct GNUNET_PeerIdentity *pid)
- {
- GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
- "Informing CORE clients about disconnect from %s\n",
- GNUNET_i2s (pid));
- for (struct TransportClient *tc = clients_head; NULL != tc; tc = tc->next)
- {
- struct GNUNET_MQ_Envelope *env;
- struct DisconnectInfoMessage *dim;
- if (CT_CORE != tc->type)
- continue;
- env = GNUNET_MQ_msg (dim, GNUNET_MESSAGE_TYPE_TRANSPORT_DISCONNECT);
- dim->peer = *pid;
- GNUNET_MQ_send (tc->mq, env);
- }
- }
- /**
- * Free entry in #dv_routes. First frees all hops to the target, and
- * if there are no entries left, frees @a dv as well.
- *
- * @param dv route to free
- */
- static void
- free_dv_route (struct DistanceVector *dv)
- {
- struct DistanceVectorHop *dvh;
- while (NULL != (dvh = dv->dv_head))
- free_distance_vector_hop (dvh);
- if (NULL == dv->dv_head)
- {
- struct VirtualLink *vl;
- GNUNET_assert (
- GNUNET_YES ==
- GNUNET_CONTAINER_multipeermap_remove (dv_routes, &dv->target, dv));
- if (NULL != (vl = dv->vl))
- {
- GNUNET_assert (dv == vl->dv);
- vl->dv = NULL;
- if (NULL == vl->n)
- {
- cores_send_disconnect_info (&dv->target);
- free_virtual_link (vl);
- }
- else
- {
- GNUNET_SCHEDULER_cancel (vl->visibility_task);
- vl->visibility_task = GNUNET_SCHEDULER_add_now (&check_link_down, vl);
- }
- dv->vl = NULL;
- }
- if (NULL != dv->timeout_task)
- {
- GNUNET_SCHEDULER_cancel (dv->timeout_task);
- dv->timeout_task = NULL;
- }
- GNUNET_free (dv);
- }
- }
- /**
- * Notify monitor @a tc about an event. That @a tc
- * cares about the event has already been checked.
- *
- * Send @a tc information in @a me about a @a peer's status with
- * respect to some @a address to all monitors that care.
- *
- * @param tc monitor to inform
- * @param peer peer the information is about
- * @param address address the information is about
- * @param nt network type associated with @a address
- * @param me detailed information to transmit
- */
- static void
- notify_monitor (struct TransportClient *tc,
- const struct GNUNET_PeerIdentity *peer,
- const char *address,
- enum GNUNET_NetworkType nt,
- const struct MonitorEvent *me)
- {
- struct GNUNET_MQ_Envelope *env;
- struct GNUNET_TRANSPORT_MonitorData *md;
- size_t addr_len = strlen (address) + 1;
- env = GNUNET_MQ_msg_extra (md,
- addr_len,
- GNUNET_MESSAGE_TYPE_TRANSPORT_MONITOR_DATA);
- md->nt = htonl ((uint32_t) nt);
- md->peer = *peer;
- md->last_validation = GNUNET_TIME_absolute_hton (me->last_validation);
- md->valid_until = GNUNET_TIME_absolute_hton (me->valid_until);
- md->next_validation = GNUNET_TIME_absolute_hton (me->next_validation);
- md->rtt = GNUNET_TIME_relative_hton (me->rtt);
- md->cs = htonl ((uint32_t) me->cs);
- md->num_msg_pending = htonl (me->num_msg_pending);
- md->num_bytes_pending = htonl (me->num_bytes_pending);
- memcpy (&md[1], address, addr_len);
- GNUNET_MQ_send (tc->mq, env);
- }
- /**
- * Send information in @a me about a @a peer's status with respect
- * to some @a address to all monitors that care.
- *
- * @param peer peer the information is about
- * @param address address the information is about
- * @param nt network type associated with @a address
- * @param me detailed information to transmit
- */
- static void
- notify_monitors (const struct GNUNET_PeerIdentity *peer,
- const char *address,
- enum GNUNET_NetworkType nt,
- const struct MonitorEvent *me)
- {
- for (struct TransportClient *tc = clients_head; NULL != tc; tc = tc->next)
- {
- if (CT_MONITOR != tc->type)
- continue;
- if (tc->details.monitor.one_shot)
- continue;
- if ((GNUNET_NO == GNUNET_is_zero (&tc->details.monitor.peer)) &&
- (0 != GNUNET_memcmp (&tc->details.monitor.peer, peer)))
- continue;
- notify_monitor (tc, peer, address, nt, me);
- }
- }
- /**
- * Called whenever a client connects. Allocates our
- * data structures associated with that client.
- *
- * @param cls closure, NULL
- * @param client identification of the client
- * @param mq message queue for the client
- * @return our `struct TransportClient`
- */
- static void *
- client_connect_cb (void *cls,
- struct GNUNET_SERVICE_Client *client,
- struct GNUNET_MQ_Handle *mq)
- {
- struct TransportClient *tc;
- (void) cls;
- tc = GNUNET_new (struct TransportClient);
- tc->client = client;
- tc->mq = mq;
- GNUNET_CONTAINER_DLL_insert (clients_head, clients_tail, tc);
- GNUNET_log (GNUNET_ERROR_TYPE_DEBUG, "Client %p connected\n", tc);
- return tc;
- }
- /**
- * Free @a rc
- *
- * @param rc data structure to free
- */
- static void
- free_reassembly_context (struct ReassemblyContext *rc)
- {
- struct Neighbour *n = rc->neighbour;
- GNUNET_assert (rc == GNUNET_CONTAINER_heap_remove_node (rc->hn));
- GNUNET_assert (GNUNET_OK ==
- GNUNET_CONTAINER_multihashmap32_remove (n->reassembly_map,
- rc->msg_uuid.uuid,
- rc));
- GNUNET_free (rc);
- }
- /**
- * Task run to clean up reassembly context of a neighbour that have expired.
- *
- * @param cls a `struct Neighbour`
- */
- static void
- reassembly_cleanup_task (void *cls)
- {
- struct Neighbour *n = cls;
- struct ReassemblyContext *rc;
- n->reassembly_timeout_task = NULL;
- while (NULL != (rc = GNUNET_CONTAINER_heap_peek (n->reassembly_heap)))
- {
- if (0 == GNUNET_TIME_absolute_get_remaining (rc->reassembly_timeout)
- .rel_value_us)
- {
- free_reassembly_context (rc);
- continue;
- }
- GNUNET_assert (NULL == n->reassembly_timeout_task);
- n->reassembly_timeout_task =
- GNUNET_SCHEDULER_add_at (rc->reassembly_timeout,
- &reassembly_cleanup_task,
- n);
- return;
- }
- }
- /**
- * function called to #free_reassembly_context().
- *
- * @param cls NULL
- * @param key unused
- * @param value a `struct ReassemblyContext` to free
- * @return #GNUNET_OK (continue iteration)
- */
- static int
- free_reassembly_cb (void *cls, uint32_t key, void *value)
- {
- struct ReassemblyContext *rc = value;
- (void) cls;
- (void) key;
- free_reassembly_context (rc);
- return GNUNET_OK;
- }
- /**
- * Release memory used by @a neighbour.
- *
- * @param neighbour neighbour entry to free
- */
- static void
- free_neighbour (struct Neighbour *neighbour)
- {
- struct DistanceVectorHop *dvh;
- struct VirtualLink *vl;
- GNUNET_assert (NULL == neighbour->queue_head);
- GNUNET_assert (GNUNET_YES ==
- GNUNET_CONTAINER_multipeermap_remove (neighbours,
- &neighbour->pid,
- neighbour));
- if (NULL != neighbour->reassembly_map)
- {
- GNUNET_CONTAINER_multihashmap32_iterate (neighbour->reassembly_map,
- &free_reassembly_cb,
- NULL);
- GNUNET_CONTAINER_multihashmap32_destroy (neighbour->reassembly_map);
- neighbour->reassembly_map = NULL;
- GNUNET_CONTAINER_heap_destroy (neighbour->reassembly_heap);
- neighbour->reassembly_heap = NULL;
- }
- while (NULL != (dvh = neighbour->dv_head))
- {
- struct DistanceVector *dv = dvh->dv;
- free_distance_vector_hop (dvh);
- if (NULL == dv->dv_head)
- free_dv_route (dv);
- }
- if (NULL != neighbour->reassembly_timeout_task)
- {
- GNUNET_SCHEDULER_cancel (neighbour->reassembly_timeout_task);
- neighbour->reassembly_timeout_task = NULL;
- }
- if (NULL != neighbour->get)
- {
- GNUNET_PEERSTORE_iterate_cancel (neighbour->get);
- neighbour->get = NULL;
- }
- if (NULL != neighbour->sc)
- {
- GNUNET_PEERSTORE_store_cancel (neighbour->sc);
- neighbour->sc = NULL;
- }
- if (NULL != (vl = neighbour->vl))
- {
- GNUNET_assert (neighbour == vl->n);
- vl->n = NULL;
- if (NULL == vl->dv)
- {
- cores_send_disconnect_info (&vl->target);
- free_virtual_link (vl);
- }
- else
- {
- GNUNET_SCHEDULER_cancel (vl->visibility_task);
- vl->visibility_task = GNUNET_SCHEDULER_add_now (&check_link_down, vl);
- }
- neighbour->vl = NULL;
- }
- GNUNET_free (neighbour);
- }
- /**
- * Send message to CORE clients that we lost a connection.
- *
- * @param tc client to inform (must be CORE client)
- * @param pid peer the connection is for
- */
- static void
- core_send_connect_info (struct TransportClient *tc,
- const struct GNUNET_PeerIdentity *pid)
- {
- struct GNUNET_MQ_Envelope *env;
- struct ConnectInfoMessage *cim;
- GNUNET_assert (CT_CORE == tc->type);
- env = GNUNET_MQ_msg (cim, GNUNET_MESSAGE_TYPE_TRANSPORT_CONNECT);
- cim->id = *pid;
- GNUNET_MQ_send (tc->mq, env);
- }
- /**
- * Send message to CORE clients that we gained a connection
- *
- * @param pid peer the queue was for
- */
- static void
- cores_send_connect_info (const struct GNUNET_PeerIdentity *pid)
- {
- GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
- "Informing CORE clients about connection to %s\n",
- GNUNET_i2s (pid));
- for (struct TransportClient *tc = clients_head; NULL != tc; tc = tc->next)
- {
- if (CT_CORE != tc->type)
- continue;
- core_send_connect_info (tc, pid);
- }
- }
- /**
- * We believe we are ready to transmit a message on a queue. Gives the
- * message to the communicator for transmission (updating the tracker,
- * and re-scheduling itself if applicable).
- *
- * @param cls the `struct Queue` to process transmissions for
- */
- static void
- transmit_on_queue (void *cls);
- /**
- * Called whenever something changed that might effect when we
- * try to do the next transmission on @a queue using #transmit_on_queue().
- *
- * @param queue the queue to do scheduling for
- * @param p task priority to use, if @a queue is scheduled
- */
- static void
- schedule_transmit_on_queue (struct Queue *queue,
- enum GNUNET_SCHEDULER_Priority p)
- {
- if (queue->tc->details.communicator.total_queue_length >=
- COMMUNICATOR_TOTAL_QUEUE_LIMIT)
- {
- GNUNET_STATISTICS_update (
- GST_stats,
- "# Transmission throttled due to communicator queue limit",
- 1,
- GNUNET_NO);
- queue->idle = GNUNET_NO;
- return;
- }
- if (queue->queue_length >= QUEUE_LENGTH_LIMIT)
- {
- GNUNET_STATISTICS_update (GST_stats,
- "# Transmission throttled due to queue queue limit",
- 1,
- GNUNET_NO);
- queue->idle = GNUNET_NO;
- return;
- }
- /* queue might indeed be ready, schedule it */
- if (NULL != queue->transmit_task)
- GNUNET_SCHEDULER_cancel (queue->transmit_task);
- queue->transmit_task =
- GNUNET_SCHEDULER_add_with_priority (p, &transmit_on_queue, queue);
- GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
- "Considering transmission on queue `%s' to %s\n",
- queue->address,
- GNUNET_i2s (&queue->neighbour->pid));
- }
- /**
- * Task run to check whether the hops of the @a cls still
- * are validated, or if we need to core about disconnection.
- *
- * @param cls a `struct VirtualLink`
- */
- static void
- check_link_down (void *cls)
- {
- struct VirtualLink *vl = cls;
- struct DistanceVector *dv = vl->dv;
- struct Neighbour *n = vl->n;
- struct GNUNET_TIME_Absolute dvh_timeout;
- struct GNUNET_TIME_Absolute q_timeout;
- vl->visibility_task = NULL;
- dvh_timeout = GNUNET_TIME_UNIT_ZERO_ABS;
- for (struct DistanceVectorHop *pos = dv->dv_head; NULL != pos;
- pos = pos->next_dv)
- dvh_timeout = GNUNET_TIME_absolute_max (dvh_timeout, pos->path_valid_until);
- if (0 == GNUNET_TIME_absolute_get_remaining (dvh_timeout).rel_value_us)
- {
- vl->dv->vl = NULL;
- vl->dv = NULL;
- }
- q_timeout = GNUNET_TIME_UNIT_ZERO_ABS;
- for (struct Queue *q = n->queue_head; NULL != q; q = q->next_neighbour)
- q_timeout = GNUNET_TIME_absolute_max (q_timeout, q->validated_until);
- if (0 == GNUNET_TIME_absolute_get_remaining (q_timeout).rel_value_us)
- {
- vl->n->vl = NULL;
- vl->n = NULL;
- }
- if ((NULL == vl->n) && (NULL == vl->dv))
- {
- cores_send_disconnect_info (&vl->target);
- free_virtual_link (vl);
- return;
- }
- vl->visibility_task =
- GNUNET_SCHEDULER_add_at (GNUNET_TIME_absolute_max (q_timeout, dvh_timeout),
- &check_link_down,
- vl);
- }
- /**
- * Free @a queue.
- *
- * @param queue the queue to free
- */
- static void
- free_queue (struct Queue *queue)
- {
- struct Neighbour *neighbour = queue->neighbour;
- struct TransportClient *tc = queue->tc;
- struct MonitorEvent me = { .cs = GNUNET_TRANSPORT_CS_DOWN,
- .rtt = GNUNET_TIME_UNIT_FOREVER_REL };
- struct QueueEntry *qe;
- int maxxed;
- struct PendingAcknowledgement *pa;
- struct VirtualLink *vl;
- if (NULL != queue->transmit_task)
- {
- GNUNET_SCHEDULER_cancel (queue->transmit_task);
- queue->transmit_task = NULL;
- }
- while (NULL != (pa = queue->pa_head))
- {
- GNUNET_CONTAINER_MDLL_remove (queue, queue->pa_head, queue->pa_tail, pa);
- pa->queue = NULL;
- }
- GNUNET_CONTAINER_MDLL_remove (neighbour,
- neighbour->queue_head,
- neighbour->queue_tail,
- queue);
- GNUNET_CONTAINER_MDLL_remove (client,
- tc->details.communicator.queue_head,
- tc->details.communicator.queue_tail,
- queue);
- maxxed = (COMMUNICATOR_TOTAL_QUEUE_LIMIT >=
- tc->details.communicator.total_queue_length);
- while (NULL != (qe = queue->queue_head))
- {
- GNUNET_CONTAINER_DLL_remove (queue->queue_head, queue->queue_tail, qe);
- queue->queue_length--;
- tc->details.communicator.total_queue_length--;
- if (NULL != qe->pm)
- {
- GNUNET_assert (qe == qe->pm->qe);
- qe->pm->qe = NULL;
- }
- GNUNET_free (qe);
- }
- GNUNET_assert (0 == queue->queue_length);
- if ((maxxed) && (COMMUNICATOR_TOTAL_QUEUE_LIMIT <
- tc->details.communicator.total_queue_length))
- {
- /* Communicator dropped below threshold, resume all _other_ queues */
- GNUNET_STATISTICS_update (
- GST_stats,
- "# Transmission throttled due to communicator queue limit",
- -1,
- GNUNET_NO);
- for (struct Queue *s = tc->details.communicator.queue_head; NULL != s;
- s = s->next_client)
- schedule_transmit_on_queue (s, GNUNET_SCHEDULER_PRIORITY_DEFAULT);
- }
- notify_monitors (&neighbour->pid, queue->address, queue->nt, &me);
- GNUNET_free (queue);
- vl = lookup_virtual_link (&neighbour->pid);
- if ((NULL != vl) && (neighbour == vl->n))
- {
- GNUNET_SCHEDULER_cancel (vl->visibility_task);
- check_link_down (vl);
- }
- if (NULL == neighbour->queue_head)
- {
- free_neighbour (neighbour);
- }
- }
- /**
- * Free @a ale
- *
- * @param ale address list entry to free
- */
- static void
- free_address_list_entry (struct AddressListEntry *ale)
- {
- struct TransportClient *tc = ale->tc;
- GNUNET_CONTAINER_DLL_remove (tc->details.communicator.addr_head,
- tc->details.communicator.addr_tail,
- ale);
- if (NULL != ale->sc)
- {
- GNUNET_PEERSTORE_store_cancel (ale->sc);
- ale->sc = NULL;
- }
- if (NULL != ale->st)
- {
- GNUNET_SCHEDULER_cancel (ale->st);
- ale->st = NULL;
- }
- GNUNET_free (ale);
- }
- /**
- * Stop the peer request in @a value.
- *
- * @param cls a `struct TransportClient` that no longer makes the request
- * @param pid the peer's identity
- * @param value a `struct PeerRequest`
- * @return #GNUNET_YES (always)
- */
- static int
- stop_peer_request (void *cls,
- const struct GNUNET_PeerIdentity *pid,
- void *value)
- {
- struct TransportClient *tc = cls;
- struct PeerRequest *pr = value;
- GNUNET_PEERSTORE_watch_cancel (pr->wc);
- GNUNET_assert (
- GNUNET_YES ==
- GNUNET_CONTAINER_multipeermap_remove (tc->details.application.requests,
- pid,
- pr));
- GNUNET_free (pr);
- return GNUNET_OK;
- }
- /**
- * Called whenever a client is disconnected. Frees our
- * resources associated with that client.
- *
- * @param cls closure, NULL
- * @param client identification of the client
- * @param app_ctx our `struct TransportClient`
- */
- static void
- client_disconnect_cb (void *cls,
- struct GNUNET_SERVICE_Client *client,
- void *app_ctx)
- {
- struct TransportClient *tc = app_ctx;
- (void) cls;
- (void) client;
- GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
- "Client %p disconnected, cleaning up.\n",
- tc);
- GNUNET_CONTAINER_DLL_remove (clients_head, clients_tail, tc);
- switch (tc->type)
- {
- case CT_NONE:
- break;
- case CT_CORE: {
- struct PendingMessage *pm;
- while (NULL != (pm = tc->details.core.pending_msg_head))
- {
- GNUNET_CONTAINER_MDLL_remove (client,
- tc->details.core.pending_msg_head,
- tc->details.core.pending_msg_tail,
- pm);
- pm->client = NULL;
- }
- }
- break;
- case CT_MONITOR:
- break;
- case CT_COMMUNICATOR: {
- struct Queue *q;
- struct AddressListEntry *ale;
- while (NULL != (q = tc->details.communicator.queue_head))
- free_queue (q);
- while (NULL != (ale = tc->details.communicator.addr_head))
- free_address_list_entry (ale);
- GNUNET_free (tc->details.communicator.address_prefix);
- }
- break;
- case CT_APPLICATION:
- GNUNET_CONTAINER_multipeermap_iterate (tc->details.application.requests,
- &stop_peer_request,
- tc);
- GNUNET_CONTAINER_multipeermap_destroy (tc->details.application.requests);
- break;
- }
- GNUNET_free (tc);
- }
- /**
- * Iterator telling new CORE client about all existing
- * connections to peers.
- *
- * @param cls the new `struct TransportClient`
- * @param pid a connected peer
- * @param value the `struct Neighbour` with more information
- * @return #GNUNET_OK (continue to iterate)
- */
- static int
- notify_client_connect_info (void *cls,
- const struct GNUNET_PeerIdentity *pid,
- void *value)
- {
- struct TransportClient *tc = cls;
- (void) value;
- GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
- "Telling new CORE client about existing connection to %s\n",
- GNUNET_i2s (pid));
- core_send_connect_info (tc, pid);
- return GNUNET_OK;
- }
- /**
- * Initialize a "CORE" client. We got a start message from this
- * client, so add it to the list of clients for broadcasting of
- * inbound messages.
- *
- * @param cls the client
- * @param start the start message that was sent
- */
- static void
- handle_client_start (void *cls, const struct StartMessage *start)
- {
- struct TransportClient *tc = cls;
- uint32_t options;
- options = ntohl (start->options);
- if ((0 != (1 & options)) &&
- (0 != GNUNET_memcmp (&start->self, &GST_my_identity)))
- {
- /* client thinks this is a different peer, reject */
- GNUNET_break (0);
- GNUNET_SERVICE_client_drop (tc->client);
- return;
- }
- if (CT_NONE != tc->type)
- {
- GNUNET_break (0);
- GNUNET_SERVICE_client_drop (tc->client);
- return;
- }
- tc->type = CT_CORE;
- GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
- "New CORE client with PID %s registered\n",
- GNUNET_i2s (&start->self));
- GNUNET_CONTAINER_multipeermap_iterate (neighbours,
- ¬ify_client_connect_info,
- tc);
- GNUNET_SERVICE_client_continue (tc->client);
- }
- /**
- * Client asked for transmission to a peer. Process the request.
- *
- * @param cls the client
- * @param obm the send message that was sent
- */
- static int
- check_client_send (void *cls, const struct OutboundMessage *obm)
- {
- struct TransportClient *tc = cls;
- uint16_t size;
- const struct GNUNET_MessageHeader *obmm;
- if (CT_CORE != tc->type)
- {
- GNUNET_break (0);
- return GNUNET_SYSERR;
- }
- size = ntohs (obm->header.size) - sizeof(struct OutboundMessage);
- if (size < sizeof(struct GNUNET_MessageHeader))
- {
- GNUNET_break (0);
- return GNUNET_SYSERR;
- }
- obmm = (const struct GNUNET_MessageHeader *) &obm[1];
- if (size != ntohs (obmm->size))
- {
- GNUNET_break (0);
- return GNUNET_SYSERR;
- }
- return GNUNET_OK;
- }
- /**
- * Send a response to the @a pm that we have processed a "send"
- * request. Sends a confirmation to the "core" client responsible for
- * the original request and free's @a pm.
- *
- * @param pm handle to the original pending message
- */
- static void
- client_send_response (struct PendingMessage *pm)
- {
- struct TransportClient *tc = pm->client;
- struct VirtualLink *vl = pm->vl;
- if (NULL != tc)
- {
- struct GNUNET_MQ_Envelope *env;
- struct SendOkMessage *som;
- env = GNUNET_MQ_msg (som, GNUNET_MESSAGE_TYPE_TRANSPORT_SEND_OK);
- som->peer = vl->target;
- GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
- "Confirming transmission of <%llu> to %s\n",
- pm->logging_uuid,
- GNUNET_i2s (&vl->target));
- GNUNET_MQ_send (tc->mq, env);
- }
- free_pending_message (pm);
- }
- /**
- * Pick @a hops_array_length random DV paths satisfying @a options
- *
- * @param dv data structure to pick paths from
- * @param options constraints to satisfy
- * @param hops_array[out] set to the result
- * @param hops_array_length length of the @a hops_array
- * @return number of entries set in @a hops_array
- */
- static unsigned int
- pick_random_dv_hops (const struct DistanceVector *dv,
- enum RouteMessageOptions options,
- struct DistanceVectorHop **hops_array,
- unsigned int hops_array_length)
- {
- uint64_t choices[hops_array_length];
- uint64_t num_dv;
- unsigned int dv_count;
- /* Pick random vectors, but weighted by distance, giving more weight
- to shorter vectors */
- num_dv = 0;
- dv_count = 0;
- for (struct DistanceVectorHop *pos = dv->dv_head; NULL != pos;
- pos = pos->next_dv)
- {
- if ((0 == (options & RMO_UNCONFIRMED_ALLOWED)) &&
- (GNUNET_TIME_absolute_get_remaining (pos->path_valid_until)
- .rel_value_us == 0))
- continue; /* pos unconfirmed and confirmed required */
- num_dv += MAX_DV_HOPS_ALLOWED - pos->distance;
- dv_count++;
- }
- if (0 == dv_count)
- return 0;
- if (dv_count <= hops_array_length)
- {
- dv_count = 0;
- for (struct DistanceVectorHop *pos = dv->dv_head; NULL != pos;
- pos = pos->next_dv)
- hops_array[dv_count++] = pos;
- return dv_count;
- }
- for (unsigned int i = 0; i < hops_array_length; i++)
- {
- int ok = GNUNET_NO;
- while (GNUNET_NO == ok)
- {
- choices[i] =
- GNUNET_CRYPTO_random_u64 (GNUNET_CRYPTO_QUALITY_WEAK, num_dv);
- ok = GNUNET_YES;
- for (unsigned int j = 0; j < i; j++)
- if (choices[i] == choices[j])
- {
- ok = GNUNET_NO;
- break;
- }
- }
- }
- dv_count = 0;
- num_dv = 0;
- for (struct DistanceVectorHop *pos = dv->dv_head; NULL != pos;
- pos = pos->next_dv)
- {
- uint32_t delta = MAX_DV_HOPS_ALLOWED - pos->distance;
- if ((0 == (options & RMO_UNCONFIRMED_ALLOWED)) &&
- (GNUNET_TIME_absolute_get_remaining (pos->path_valid_until)
- .rel_value_us == 0))
- continue; /* pos unconfirmed and confirmed required */
- for (unsigned int i = 0; i < hops_array_length; i++)
- if ((num_dv <= choices[i]) && (num_dv + delta > choices[i]))
- hops_array[dv_count++] = pos;
- num_dv += delta;
- }
- return dv_count;
- }
- /**
- * Communicator started. Test message is well-formed.
- *
- * @param cls the client
- * @param cam the send message that was sent
- */
- static int
- check_communicator_available (
- void *cls,
- const struct GNUNET_TRANSPORT_CommunicatorAvailableMessage *cam)
- {
- struct TransportClient *tc = cls;
- uint16_t size;
- if (CT_NONE != tc->type)
- {
- GNUNET_break (0);
- return GNUNET_SYSERR;
- }
- tc->type = CT_COMMUNICATOR;
- size = ntohs (cam->header.size) - sizeof(*cam);
- if (0 == size)
- return GNUNET_OK; /* receive-only communicator */
- GNUNET_MQ_check_zero_termination (cam);
- return GNUNET_OK;
- }
- /**
- * Send ACK to communicator (if requested) and free @a cmc.
- *
- * @param cmc context for which we are done handling the message
- */
- static void
- finish_cmc_handling (struct CommunicatorMessageContext *cmc)
- {
- if (0 != ntohl (cmc->im.fc_on))
- {
- /* send ACK when done to communicator for flow control! */
- struct GNUNET_MQ_Envelope *env;
- struct GNUNET_TRANSPORT_IncomingMessageAck *ack;
- env = GNUNET_MQ_msg (ack, GNUNET_MESSAGE_TYPE_TRANSPORT_INCOMING_MSG_ACK);
- ack->reserved = htonl (0);
- ack->fc_id = cmc->im.fc_id;
- ack->sender = cmc->im.sender;
- GNUNET_MQ_send (cmc->tc->mq, env);
- }
- GNUNET_SERVICE_client_continue (cmc->tc->client);
- GNUNET_free (cmc);
- }
- /**
- * Client confirms that it is done handling message(s) to a particular
- * peer. We may now provide more messages to CORE for this peer.
- *
- * Notifies the respective queues that more messages can now be received.
- *
- * @param cls the client
- * @param rom the message that was sent
- */
- static void
- handle_client_recv_ok (void *cls, const struct RecvOkMessage *rom)
- {
- struct TransportClient *tc = cls;
- struct VirtualLink *vl;
- uint32_t delta;
- struct CommunicatorMessageContext *cmc;
- if (CT_CORE != tc->type)
- {
- GNUNET_break (0);
- GNUNET_SERVICE_client_drop (tc->client);
- return;
- }
- vl = lookup_virtual_link (&rom->peer);
- if (NULL == vl)
- {
- GNUNET_STATISTICS_update (GST_stats,
- "# RECV_OK dropped: virtual link unknown",
- 1,
- GNUNET_NO);
- GNUNET_SERVICE_client_continue (tc->client);
- return;
- }
- delta = ntohl (rom->increase_window_delta);
- vl->core_recv_window += delta;
- if (vl->core_recv_window <= 0)
- return;
- /* resume communicators */
- while (NULL != (cmc = vl->cmc_tail))
- {
- GNUNET_CONTAINER_DLL_remove (vl->cmc_head, vl->cmc_tail, cmc);
- finish_cmc_handling (cmc);
- }
- }
- /**
- * Communicator started. Process the request.
- *
- * @param cls the client
- * @param cam the send message that was sent
- */
- static void
- handle_communicator_available (
- void *cls,
- const struct GNUNET_TRANSPORT_CommunicatorAvailableMessage *cam)
- {
- struct TransportClient *tc = cls;
- uint16_t size;
- size = ntohs (cam->header.size) - sizeof(*cam);
- if (0 == size)
- {
- GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
- "Receive-only communicator connected\n");
- return; /* receive-only communicator */
- }
- tc->details.communicator.address_prefix =
- GNUNET_strdup ((const char *) &cam[1]);
- tc->details.communicator.cc =
- (enum GNUNET_TRANSPORT_CommunicatorCharacteristics) ntohl (cam->cc);
- GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
- "Communicator with prefix `%s' connected\n",
- tc->details.communicator.address_prefix);
- GNUNET_SERVICE_client_continue (tc->client);
- }
- /**
- * Communicator requests backchannel transmission. Check the request.
- *
- * @param cls the client
- * @param cb the send message that was sent
- * @return #GNUNET_OK if message is well-formed
- */
- static int
- check_communicator_backchannel (
- void *cls,
- const struct GNUNET_TRANSPORT_CommunicatorBackchannel *cb)
- {
- const struct GNUNET_MessageHeader *inbox;
- const char *is;
- uint16_t msize;
- uint16_t isize;
- (void) cls;
- msize = ntohs (cb->header.size) - sizeof(*cb);
- inbox = (const struct GNUNET_MessageHeader *) &cb[1];
- isize = ntohs (inbox->size);
- if (isize >= msize)
- {
- GNUNET_break (0);
- return GNUNET_SYSERR;
- }
- is = (const char *) inbox;
- is += isize;
- msize -= isize;
- GNUNET_assert (0 < msize);
- if ('\0' != is[msize - 1])
- {
- GNUNET_break (0);
- return GNUNET_SYSERR;
- }
- return GNUNET_OK;
- }
- /**
- * Ensure ephemeral keys in our @a dv are current. If no current one exists,
- * set it up.
- *
- * @param dv[in,out] virtual link to update ephemeral for
- */
- static void
- update_ephemeral (struct DistanceVector *dv)
- {
- struct EphemeralConfirmationPS ec;
- if (0 !=
- GNUNET_TIME_absolute_get_remaining (dv->ephemeral_validity).rel_value_us)
- return;
- dv->monotime = GNUNET_TIME_absolute_get_monotonic (GST_cfg);
- dv->ephemeral_validity =
- GNUNET_TIME_absolute_add (dv->monotime, EPHEMERAL_VALIDITY);
- GNUNET_CRYPTO_ecdhe_key_create (&dv->private_key);
- GNUNET_CRYPTO_ecdhe_key_get_public (&dv->private_key, &dv->ephemeral_key);
- ec.purpose.purpose = htonl (GNUNET_SIGNATURE_PURPOSE_TRANSPORT_EPHEMERAL);
- ec.purpose.size = htonl (sizeof(ec));
- ec.target = dv->target;
- ec.ephemeral_key = dv->ephemeral_key;
- GNUNET_CRYPTO_eddsa_sign (GST_my_private_key,
- &ec,
- &dv->sender_sig);
- }
- /**
- * Send the message @a payload on @a queue.
- *
- * @param queue the queue to use for transmission
- * @param pm pending message to update once transmission is done, may be NULL!
- * @param payload the payload to send (encapsulated in a
- * #GNUNET_MESSAGE_TYPE_TRANSPORT_SEND_MSG).
- * @param payload_size number of bytes in @a payload
- */
- static void
- queue_send_msg (struct Queue *queue,
- struct PendingMessage *pm,
- const void *payload,
- size_t payload_size)
- {
- struct Neighbour *n = queue->neighbour;
- struct GNUNET_TRANSPORT_SendMessageTo *smt;
- struct GNUNET_MQ_Envelope *env;
- queue->idle = GNUNET_NO;
- GNUNET_log (
- GNUNET_ERROR_TYPE_DEBUG,
- "Queueing %u bytes of payload for transmission <%llu> on queue %llu to %s\n",
- (unsigned int) payload_size,
- (NULL == pm) ? 0 : pm->logging_uuid,
- (unsigned long long) queue->qid,
- GNUNET_i2s (&queue->neighbour->pid));
- env = GNUNET_MQ_msg_extra (smt,
- payload_size,
- GNUNET_MESSAGE_TYPE_TRANSPORT_SEND_MSG);
- smt->qid = queue->qid;
- smt->mid = queue->mid_gen;
- smt->receiver = n->pid;
- memcpy (&smt[1], payload, payload_size);
- {
- /* Pass the env to the communicator of queue for transmission. */
- struct QueueEntry *qe;
- qe = GNUNET_new (struct QueueEntry);
- qe->mid = queue->mid_gen++;
- qe->queue = queue;
- if (NULL != pm)
- {
- qe->pm = pm;
- GNUNET_assert (NULL == pm->qe);
- pm->qe = qe;
- }
- GNUNET_CONTAINER_DLL_insert (queue->queue_head, queue->queue_tail, qe);
- GNUNET_assert (CT_COMMUNICATOR == queue->tc->type);
- queue->queue_length++;
- queue->tc->details.communicator.total_queue_length++;
- if (COMMUNICATOR_TOTAL_QUEUE_LIMIT ==
- queue->tc->details.communicator.total_queue_length)
- queue->idle = GNUNET_NO;
- if (QUEUE_LENGTH_LIMIT == queue->queue_length)
- queue->idle = GNUNET_NO;
- GNUNET_MQ_send (queue->tc->mq, env);
- }
- }
- /**
- * Pick a queue of @a n under constraints @a options and schedule
- * transmission of @a hdr.
- *
- * @param n neighbour to send to
- * @param hdr message to send as payload
- * @param options whether queues must be confirmed or not,
- * and whether we may pick multiple (2) queues
- * @return expected RTT for transmission, #GNUNET_TIME_UNIT_FOREVER_REL if sending failed
- */
- static struct GNUNET_TIME_Relative
- route_via_neighbour (const struct Neighbour *n,
- const struct GNUNET_MessageHeader *hdr,
- enum RouteMessageOptions options)
- {
- struct GNUNET_TIME_Absolute now;
- unsigned int candidates;
- unsigned int sel1;
- unsigned int sel2;
- struct GNUNET_TIME_Relative rtt;
- /* Pick one or two 'random' queues from n (under constraints of options) */
- now = GNUNET_TIME_absolute_get ();
- /* FIXME-OPTIMIZE: give queues 'weights' and pick proportional to
- weight in the future; weight could be assigned by observed
- bandwidth (note: not sure if we should do this for this type
- of control traffic though). */
- candidates = 0;
- for (struct Queue *pos = n->queue_head; NULL != pos;
- pos = pos->next_neighbour)
- {
- if ((0 == (options & RMO_UNCONFIRMED_ALLOWED)) ||
- (pos->validated_until.abs_value_us > now.abs_value_us))
- candidates++;
- }
- if (0 == candidates)
- {
- /* This can happen rarely if the last confirmed queue timed
- out just as we were beginning to process this message. */
- GNUNET_log (GNUNET_ERROR_TYPE_INFO,
- "Could not route message of type %u to %s: no valid queue\n",
- ntohs (hdr->type),
- GNUNET_i2s (&n->pid));
- GNUNET_STATISTICS_update (GST_stats,
- "# route selection failed (all no valid queue)",
- 1,
- GNUNET_NO);
- return GNUNET_TIME_UNIT_FOREVER_REL;
- }
- rtt = GNUNET_TIME_UNIT_FOREVER_REL;
- sel1 = GNUNET_CRYPTO_random_u32 (GNUNET_CRYPTO_QUALITY_WEAK, candidates);
- if (0 == (options & RMO_REDUNDANT))
- sel2 = candidates; /* picks none! */
- else
- sel2 = GNUNET_CRYPTO_random_u32 (GNUNET_CRYPTO_QUALITY_WEAK, candidates);
- candidates = 0;
- for (struct Queue *pos = n->queue_head; NULL != pos;
- pos = pos->next_neighbour)
- {
- if ((0 == (options & RMO_UNCONFIRMED_ALLOWED)) ||
- (pos->validated_until.abs_value_us > now.abs_value_us))
- {
- if ((sel1 == candidates) || (sel2 == candidates))
- {
- GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
- "Routing message of type %u to %s using %s (#%u)\n",
- ntohs (hdr->type),
- GNUNET_i2s (&n->pid),
- pos->address,
- (sel1 == candidates) ? 1 : 2);
- rtt = GNUNET_TIME_relative_min (rtt, pos->pd.aged_rtt);
- queue_send_msg (pos, NULL, hdr, ntohs (hdr->size));
- }
- candidates++;
- }
- }
- return rtt;
- }
- /**
- * Structure of the key material used to encrypt backchannel messages.
- */
- struct DVKeyState
- {
- /**
- * State of our block cipher.
- */
- gcry_cipher_hd_t cipher;
- /**
- * Actual key material.
- */
- struct
- {
- /**
- * Key used for HMAC calculations (via #GNUNET_CRYPTO_hmac()).
- */
- struct GNUNET_CRYPTO_AuthKey hmac_key;
- /**
- * Symmetric key to use for encryption.
- */
- char aes_key[256 / 8];
- /**
- * Counter value to use during setup.
- */
- char aes_ctr[128 / 8];
- } material;
- };
- /**
- * Given the key material in @a km and the initialization vector
- * @a iv, setup the key material for the backchannel in @a key.
- *
- * @param km raw master secret
- * @param iv initialization vector
- * @param key[out] symmetric cipher and HMAC state to generate
- */
- static void
- dv_setup_key_state_from_km (const struct GNUNET_HashCode *km,
- const struct GNUNET_ShortHashCode *iv,
- struct DVKeyState *key)
- {
- /* must match #dh_key_derive_eph_pub */
- GNUNET_assert (GNUNET_YES ==
- GNUNET_CRYPTO_kdf (&key->material,
- sizeof(key->material),
- "transport-backchannel-key",
- strlen ("transport-backchannel-key"),
- &km,
- sizeof(km),
- iv,
- sizeof(*iv)));
- GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
- "Deriving backchannel key based on KM %s and IV %s\n",
- GNUNET_h2s (km),
- GNUNET_sh2s (iv));
- gcry_cipher_open (&key->cipher,
- GCRY_CIPHER_AES256 /* low level: go for speed */,
- GCRY_CIPHER_MODE_CTR,
- 0 /* flags */);
- gcry_cipher_setkey (key->cipher,
- &key->material.aes_key,
- sizeof(key->material.aes_key));
- gcry_cipher_setctr (key->cipher,
- &key->material.aes_ctr,
- sizeof(key->material.aes_ctr));
- }
- /**
- * Derive backchannel encryption key material from @a priv_ephemeral
- * and @a target and @a iv.
- *
- * @param priv_ephemeral ephemeral private key to use
- * @param target the target peer to encrypt to
- * @param iv unique IV to use
- * @param key[out] set to the key material
- */
- static void
- dh_key_derive_eph_pid (
- const struct GNUNET_CRYPTO_EcdhePrivateKey *priv_ephemeral,
- const struct GNUNET_PeerIdentity *target,
- const struct GNUNET_ShortHashCode *iv,
- struct DVKeyState *key)
- {
- struct GNUNET_HashCode km;
- GNUNET_assert (GNUNET_YES == GNUNET_CRYPTO_ecdh_eddsa (priv_ephemeral,
- &target->public_key,
- &km));
- dv_setup_key_state_from_km (&km, iv, key);
- }
- /**
- * Derive backchannel encryption key material from #GST_my_private_key
- * and @a pub_ephemeral and @a iv.
- *
- * @param priv_ephemeral ephemeral private key to use
- * @param target the target peer to encrypt to
- * @param iv unique IV to use
- * @param key[out] set to the key material
- */
- static void
- dh_key_derive_eph_pub (const struct GNUNET_CRYPTO_EcdhePublicKey *pub_ephemeral,
- const struct GNUNET_ShortHashCode *iv,
- struct DVKeyState *key)
- {
- struct GNUNET_HashCode km;
- GNUNET_assert (GNUNET_YES == GNUNET_CRYPTO_eddsa_ecdh (GST_my_private_key,
- pub_ephemeral,
- &km));
- dv_setup_key_state_from_km (&km, iv, key);
- }
- /**
- * Do HMAC calculation for backchannel messages over @a data using key
- * material from @a key.
- *
- * @param key key material (from DH)
- * @param hmac[out] set to the HMAC
- * @param data data to perform HMAC calculation over
- * @param data_size number of bytes in @a data
- */
- static void
- dv_hmac (const struct DVKeyState *key,
- struct GNUNET_HashCode *hmac,
- const void *data,
- size_t data_size)
- {
- GNUNET_CRYPTO_hmac (&key->material.hmac_key, data, data_size, hmac);
- }
- /**
- * Perform backchannel encryption using symmetric secret in @a key
- * to encrypt data from @a in to @a dst.
- *
- * @param key[in,out] key material to use
- * @param dst where to write the result
- * @param in input data to encrypt (plaintext)
- * @param in_size number of bytes of input in @a in and available at @a dst
- */
- static void
- dv_encrypt (struct DVKeyState *key, const void *in, void *dst, size_t in_size)
- {
- GNUNET_assert (0 ==
- gcry_cipher_encrypt (key->cipher, dst, in_size, in, in_size));
- }
- /**
- * Perform backchannel encryption using symmetric secret in @a key
- * to encrypt data from @a in to @a dst.
- *
- * @param key[in,out] key material to use
- * @param ciph cipher text to decrypt
- * @param out[out] output data to generate (plaintext)
- * @param out_size number of bytes of input in @a ciph and available in @a out
- */
- static void
- dv_decrypt (struct DVKeyState *key,
- void *out,
- const void *ciph,
- size_t out_size)
- {
- GNUNET_assert (
- 0 == gcry_cipher_decrypt (key->cipher, out, out_size, ciph, out_size));
- }
- /**
- * Clean up key material in @a key.
- *
- * @param key key material to clean up (memory must not be free'd!)
- */
- static void
- dv_key_clean (struct DVKeyState *key)
- {
- gcry_cipher_close (key->cipher);
- GNUNET_CRYPTO_zero_keys (&key->material, sizeof(key->material));
- }
- /**
- * Function to call to further operate on the now DV encapsulated
- * message @a hdr, forwarding it via @a next_hop under respect of
- * @a options.
- *
- * @param cls closure
- * @param next_hop next hop of the DV path
- * @param hdr encapsulated message, technically a `struct TransportDFBoxMessage`
- * @param options options of the original message
- */
- typedef void (*DVMessageHandler) (void *cls,
- struct Neighbour *next_hop,
- const struct GNUNET_MessageHeader *hdr,
- enum RouteMessageOptions options);
- /**
- * Pick a path of @a dv under constraints @a options and schedule
- * transmission of @a hdr.
- *
- * @param target neighbour to ultimately send to
- * @param num_dvhs length of the @a dvhs array
- * @param dvhs array of hops to send the message to
- * @param hdr message to send as payload
- * @param use function to call with the encapsulated message
- * @param use_cls closure for @a use
- * @param options whether path must be confirmed or not, to be passed to @a use
- * @return expected RTT for transmission, #GNUNET_TIME_UNIT_FOREVER_REL if sending failed
- */
- static struct GNUNET_TIME_Relative
- encapsulate_for_dv (struct DistanceVector *dv,
- unsigned int num_dvhs,
- struct DistanceVectorHop **dvhs,
- const struct GNUNET_MessageHeader *hdr,
- DVMessageHandler use,
- void *use_cls,
- enum RouteMessageOptions options)
- {
- struct TransportDVBoxMessage box_hdr;
- struct TransportDVBoxPayloadP payload_hdr;
- uint16_t enc_body_size = ntohs (hdr->size);
- char enc[sizeof(struct TransportDVBoxPayloadP) + enc_body_size] GNUNET_ALIGN;
- struct TransportDVBoxPayloadP *enc_payload_hdr =
- (struct TransportDVBoxPayloadP *) enc;
- struct DVKeyState key;
- struct GNUNET_TIME_Relative rtt;
- /* Encrypt payload */
- box_hdr.header.type = htons (GNUNET_MESSAGE_TYPE_TRANSPORT_DV_BOX);
- box_hdr.total_hops = htons (0);
- update_ephemeral (dv);
- box_hdr.ephemeral_key = dv->ephemeral_key;
- payload_hdr.sender_sig = dv->sender_sig;
- GNUNET_CRYPTO_random_block (GNUNET_CRYPTO_QUALITY_NONCE,
- &box_hdr.iv,
- sizeof(box_hdr.iv));
- dh_key_derive_eph_pid (&dv->private_key, &dv->target, &box_hdr.iv, &key);
- payload_hdr.sender = GST_my_identity;
- payload_hdr.monotonic_time = GNUNET_TIME_absolute_hton (dv->monotime);
- dv_encrypt (&key, &payload_hdr, enc_payload_hdr, sizeof(payload_hdr));
- dv_encrypt (&key,
- hdr,
- &enc[sizeof(struct TransportDVBoxPayloadP)],
- enc_body_size);
- dv_hmac (&key, &box_hdr.hmac, enc, sizeof(enc));
- dv_key_clean (&key);
- rtt = GNUNET_TIME_UNIT_FOREVER_REL;
- /* For each selected path, take the pre-computed header and body
- and add the path in the middle of the message; then send it. */
- for (unsigned int i = 0; i < num_dvhs; i++)
- {
- struct DistanceVectorHop *dvh = dvhs[i];
- unsigned int num_hops = dvh->distance + 1;
- char buf[sizeof(struct TransportDVBoxMessage)
- + sizeof(struct GNUNET_PeerIdentity) * num_hops
- + sizeof(struct TransportDVBoxPayloadP)
- + enc_body_size] GNUNET_ALIGN;
- struct GNUNET_PeerIdentity *dhops;
- box_hdr.header.size = htons (sizeof(buf));
- box_hdr.num_hops = htons (num_hops);
- memcpy (buf, &box_hdr, sizeof(box_hdr));
- dhops = (struct GNUNET_PeerIdentity *) &buf[sizeof(box_hdr)];
- memcpy (dhops,
- dvh->path,
- dvh->distance * sizeof(struct GNUNET_PeerIdentity));
- dhops[dvh->distance] = dv->target;
- if (GNUNET_EXTRA_LOGGING > 0)
- {
- char *path;
- path = GNUNET_strdup (GNUNET_i2s (&GST_my_identity));
- for (unsigned int j = 0; j <= num_hops; j++)
- {
- char *tmp;
- GNUNET_asprintf (&tmp, "%s-%s", path, GNUNET_i2s (&dhops[j]));
- GNUNET_free (path);
- path = tmp;
- }
- GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
- "Routing message of type %u to %s using DV (#%u/%u) via %s\n",
- ntohs (hdr->type),
- GNUNET_i2s (&dv->target),
- i + 1,
- num_dvhs + 1,
- path);
- GNUNET_free (path);
- }
- rtt = GNUNET_TIME_relative_min (rtt, dvh->pd.aged_rtt);
- memcpy (&dhops[num_hops], enc, sizeof(enc));
- use (use_cls,
- dvh->next_hop,
- (const struct GNUNET_MessageHeader *) buf,
- options);
- }
- return rtt;
- }
- /**
- * Wrapper around #route_via_neighbour() that matches the
- * #DVMessageHandler structure.
- *
- * @param cls unused
- * @param next_hop where to send next
- * @param hdr header of the message to send
- * @param options message options for queue selection
- */
- static void
- send_dv_to_neighbour (void *cls,
- struct Neighbour *next_hop,
- const struct GNUNET_MessageHeader *hdr,
- enum RouteMessageOptions options)
- {
- (void) cls;
- (void) route_via_neighbour (next_hop, hdr, options);
- }
- /**
- * We need to transmit @a hdr to @a target. If necessary, this may
- * involve DV routing. This function routes without applying flow
- * control or congestion control and should only be used for control
- * traffic.
- *
- * @param target peer to receive @a hdr
- * @param hdr header of the message to route and #GNUNET_free()
- * @param options which transmission channels are allowed
- * @return expected RTT for transmission, #GNUNET_TIME_UNIT_FOREVER_REL if sending failed
- */
- static struct GNUNET_TIME_Relative
- route_control_message_without_fc (const struct GNUNET_PeerIdentity *target,
- const struct GNUNET_MessageHeader *hdr,
- enum RouteMessageOptions options)
- {
- struct VirtualLink *vl;
- struct Neighbour *n;
- struct DistanceVector *dv;
- struct GNUNET_TIME_Relative rtt1;
- struct GNUNET_TIME_Relative rtt2;
- vl = lookup_virtual_link (target);
- GNUNET_assert (NULL != vl);
- n = vl->n;
- dv = (0 != (options & RMO_DV_ALLOWED)) ? vl->dv : NULL;
- if (0 == (options & RMO_UNCONFIRMED_ALLOWED))
- {
- /* if confirmed is required, and we do not have anything
- confirmed, drop respective options */
- if (NULL == n)
- n = lookup_neighbour (target);
- if ((NULL == dv) && (0 != (options & RMO_DV_ALLOWED)))
- dv = GNUNET_CONTAINER_multipeermap_get (dv_routes, target);
- }
- if ((NULL == n) && (NULL == dv))
- {
- GNUNET_log (GNUNET_ERROR_TYPE_INFO,
- "Cannot route message of type %u to %s: no route\n",
- ntohs (hdr->type),
- GNUNET_i2s (target));
- GNUNET_STATISTICS_update (GST_stats,
- "# Messages dropped in routing: no acceptable method",
- 1,
- GNUNET_NO);
- return GNUNET_TIME_UNIT_FOREVER_REL;
- }
- GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
- "Routing message of type %u to %s with options %X\n",
- ntohs (hdr->type),
- GNUNET_i2s (target),
- (unsigned int) options);
- /* If both dv and n are possible and we must choose:
- flip a coin for the choice between the two; for now 50/50 */
- if ((NULL != n) && (NULL != dv) && (0 == (options & RMO_REDUNDANT)))
- {
- if (0 == GNUNET_CRYPTO_random_u32 (GNUNET_CRYPTO_QUALITY_WEAK, 2))
- n = NULL;
- else
- dv = NULL;
- }
- if ((NULL != n) && (NULL != dv))
- options &= ~RMO_REDUNDANT; /* We will do one DV and one direct, that's
- enough for redunancy, so clear the flag. */
- rtt1 = GNUNET_TIME_UNIT_FOREVER_REL;
- rtt2 = GNUNET_TIME_UNIT_FOREVER_REL;
- if (NULL != n)
- {
- rtt1 = route_via_neighbour (n, hdr, options);
- }
- if (NULL != dv)
- {
- struct DistanceVectorHop *hops[2];
- unsigned int res;
- res = pick_random_dv_hops (dv,
- options,
- hops,
- (0 == (options & RMO_REDUNDANT)) ? 1 : 2);
- if (0 == res)
- {
- GNUNET_log (GNUNET_ERROR_TYPE_INFO,
- "Failed to route message, could not determine DV path\n");
- return rtt1;
- }
- rtt2 = encapsulate_for_dv (dv,
- res,
- hops,
- hdr,
- &send_dv_to_neighbour,
- NULL,
- options & (~RMO_REDUNDANT));
- }
- return GNUNET_TIME_relative_min (rtt1, rtt2);
- }
- /**
- * Something changed on the virtual link with respect to flow
- * control. Consider retransmitting the FC window size.
- *
- * @param cls a `struct VirtualLink` to work with
- */
- static void
- consider_sending_fc (void *cls)
- {
- struct VirtualLink *vl = cls;
- struct GNUNET_TIME_Absolute monotime;
- struct TransportFlowControlMessage fc;
- struct GNUNET_TIME_Relative duration;
- struct GNUNET_TIME_Relative rtt;
- duration = GNUNET_TIME_absolute_get_duration (vl->last_fc_transmission);
- /* OPTIMIZE-FC-BDP: decide sane criteria on when to do this, instead of doing
- it always! */
- /* For example, we should probably ONLY do this if a bit more than
- an RTT has passed, or if the window changed "significantly" since
- then. See vl->last_fc_rtt! NOTE: to do this properly, we also
- need an estimate for the bandwidth-delay-product for the entire
- VL, as that determines "significantly". We have the delay, but
- the bandwidth statistics need to be added for the VL!*/(void) duration;
- GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
- "Sending FC seq %u to %s with new window %llu\n",
- (unsigned int) vl->fc_seq_gen,
- GNUNET_i2s (&vl->target),
- (unsigned long long) vl->incoming_fc_window_size);
- monotime = GNUNET_TIME_absolute_get_monotonic (GST_cfg);
- vl->last_fc_transmission = monotime;
- fc.header.type = htons (GNUNET_MESSAGE_TYPE_TRANSPORT_FLOW_CONTROL);
- fc.header.size = htons (sizeof(fc));
- fc.seq = htonl (vl->fc_seq_gen++);
- fc.inbound_window_size = GNUNET_htonll (vl->incoming_fc_window_size);
- fc.outbound_sent = GNUNET_htonll (vl->outbound_fc_window_size_used);
- fc.outbound_window_size = GNUNET_htonll (vl->outbound_fc_window_size);
- fc.sender_time = GNUNET_TIME_absolute_hton (monotime);
- rtt = route_control_message_without_fc (&vl->target, &fc.header, RMO_NONE);
- if (GNUNET_TIME_UNIT_FOREVER_REL.rel_value_us == rtt.rel_value_us)
- {
- rtt = GNUNET_TIME_UNIT_SECONDS;
- GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
- "FC retransmission to %s failed, will retry in %s\n",
- GNUNET_i2s (&vl->target),
- GNUNET_STRINGS_relative_time_to_string (rtt, GNUNET_YES));
- vl->last_fc_rtt = GNUNET_TIME_UNIT_ZERO;
- }
- else
- {
- /* OPTIMIZE-FC-BDP: rtt is not ideal, we can do better! */
- vl->last_fc_rtt = rtt;
- }
- if (NULL != vl->fc_retransmit_task)
- GNUNET_SCHEDULER_cancel (vl->fc_retransmit_task);
- vl->fc_retransmit_task =
- GNUNET_SCHEDULER_add_delayed (rtt, &consider_sending_fc, vl);
- }
- /**
- * There is a message at the head of the pending messages for @a vl
- * which may be ready for transmission. Check if a queue is ready to
- * take it.
- *
- * This function must (1) check for flow control to ensure that we can
- * right now send to @a vl, (2) check that the pending message in the
- * queue is actually eligible, (3) determine if any applicable queue
- * (direct neighbour or DVH path) is ready to accept messages, and
- * (4) prioritize based on the preferences associated with the
- * pending message.
- *
- * So yeah, easy.
- *
- * @param vl virtual link where we should check for transmission
- */
- static void
- check_vl_transmission (struct VirtualLink *vl)
- {
- struct Neighbour *n = vl->n;
- struct DistanceVector *dv = vl->dv;
- struct GNUNET_TIME_Absolute now;
- int elig;
- /* Check that we have an eligible pending message!
- (cheaper than having #transmit_on_queue() find out!) */
- elig = GNUNET_NO;
- for (struct PendingMessage *pm = vl->pending_msg_head; NULL != pm;
- pm = pm->next_vl)
- {
- if (NULL != pm->qe)
- continue; /* not eligible, is in a queue! */
- if (pm->bytes_msg + vl->outbound_fc_window_size_used >
- vl->outbound_fc_window_size)
- {
- GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
- "Stalled transmision on VL %s due to flow control: %llu < %llu\n",
- GNUNET_i2s (&vl->target),
- (unsigned long long) vl->outbound_fc_window_size,
- (unsigned long long) (pm->bytes_msg
- + vl->outbound_fc_window_size_used));
- consider_sending_fc (vl);
- return; /* We have a message, but flow control says "nope" */
- }
- elig = GNUNET_YES;
- break;
- }
- if (GNUNET_NO == elig)
- return;
- /* Notify queues at direct neighbours that we are interested */
- now = GNUNET_TIME_absolute_get ();
- if (NULL != n)
- {
- for (struct Queue *queue = n->queue_head; NULL != queue;
- queue = queue->next_neighbour)
- if ((GNUNET_YES == queue->idle) &&
- (queue->validated_until.abs_value_us > now.abs_value_us))
- schedule_transmit_on_queue (queue, GNUNET_SCHEDULER_PRIORITY_DEFAULT);
- }
- /* Notify queues via DV that we are interested */
- if (NULL != dv)
- {
- /* Do DV with lower scheduler priority, which effectively means that
- IF a neighbour exists and is available, we prefer it. */
- for (struct DistanceVectorHop *pos = dv->dv_head; NULL != pos;
- pos = pos->next_dv)
- {
- struct Neighbour *nh = pos->next_hop;
- if (pos->path_valid_until.abs_value_us <= now.abs_value_us)
- continue; /* skip this one: path not validated */
- for (struct Queue *queue = nh->queue_head; NULL != queue;
- queue = queue->next_neighbour)
- if ((GNUNET_YES == queue->idle) &&
- (queue->validated_until.abs_value_us > now.abs_value_us))
- schedule_transmit_on_queue (queue,
- GNUNET_SCHEDULER_PRIORITY_BACKGROUND);
- }
- }
- }
- /**
- * Client asked for transmission to a peer. Process the request.
- *
- * @param cls the client
- * @param obm the send message that was sent
- */
- static void
- handle_client_send (void *cls, const struct OutboundMessage *obm)
- {
- struct TransportClient *tc = cls;
- struct PendingMessage *pm;
- const struct GNUNET_MessageHeader *obmm;
- uint32_t bytes_msg;
- struct VirtualLink *vl;
- enum GNUNET_MQ_PriorityPreferences pp;
- GNUNET_assert (CT_CORE == tc->type);
- obmm = (const struct GNUNET_MessageHeader *) &obm[1];
- bytes_msg = ntohs (obmm->size);
- pp = (enum GNUNET_MQ_PriorityPreferences) ntohl (obm->priority);
- vl = lookup_virtual_link (&obm->peer);
- if (NULL == vl)
- {
- /* Failure: don't have this peer as a neighbour (anymore).
- Might have gone down asynchronously, so this is NOT
- a protocol violation by CORE. Still count the event,
- as this should be rare. */
- GNUNET_SERVICE_client_continue (tc->client);
- GNUNET_STATISTICS_update (GST_stats,
- "# messages dropped (neighbour unknown)",
- 1,
- GNUNET_NO);
- return;
- }
- pm = GNUNET_malloc (sizeof(struct PendingMessage) + bytes_msg);
- pm->logging_uuid = logging_uuid_gen++;
- pm->prefs = pp;
- pm->client = tc;
- pm->vl = vl;
- pm->bytes_msg = bytes_msg;
- memcpy (&pm[1], obmm, bytes_msg);
- GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
- "Sending %u bytes as <%llu> to %s\n",
- bytes_msg,
- pm->logging_uuid,
- GNUNET_i2s (&obm->peer));
- GNUNET_CONTAINER_MDLL_insert (client,
- tc->details.core.pending_msg_head,
- tc->details.core.pending_msg_tail,
- pm);
- GNUNET_CONTAINER_MDLL_insert (vl,
- vl->pending_msg_head,
- vl->pending_msg_tail,
- pm);
- check_vl_transmission (vl);
- }
- /**
- * Communicator requests backchannel transmission. Process the request.
- * Just repacks it into our `struct TransportBackchannelEncapsulationMessage *`
- * (which for now has exactly the same format, only a different message type)
- * and passes it on for routing.
- *
- * @param cls the client
- * @param cb the send message that was sent
- */
- static void
- handle_communicator_backchannel (
- void *cls,
- const struct GNUNET_TRANSPORT_CommunicatorBackchannel *cb)
- {
- struct TransportClient *tc = cls;
- const struct GNUNET_MessageHeader *inbox =
- (const struct GNUNET_MessageHeader *) &cb[1];
- uint16_t isize = ntohs (inbox->size);
- const char *is = ((const char *) &cb[1]) + isize;
- char
- mbuf[isize
- + sizeof(struct
- TransportBackchannelEncapsulationMessage)] GNUNET_ALIGN;
- struct TransportBackchannelEncapsulationMessage *be =
- (struct TransportBackchannelEncapsulationMessage *) mbuf;
- /* 0-termination of 'is' was checked already in
- #check_communicator_backchannel() */
- GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
- "Preparing backchannel transmission to %s:%s of type %u\n",
- GNUNET_i2s (&cb->pid),
- is,
- ntohs (inbox->size));
- /* encapsulate and encrypt message */
- be->header.type =
- htons (GNUNET_MESSAGE_TYPE_TRANSPORT_BACKCHANNEL_ENCAPSULATION);
- be->header.size = htons (sizeof(mbuf));
- memcpy (&be[1], inbox, isize);
- memcpy (&mbuf[sizeof(struct TransportBackchannelEncapsulationMessage)
- + isize],
- is,
- strlen (is) + 1);
- route_control_message_without_fc (&cb->pid, &be->header, RMO_DV_ALLOWED);
- GNUNET_SERVICE_client_continue (tc->client);
- }
- /**
- * Address of our peer added. Test message is well-formed.
- *
- * @param cls the client
- * @param aam the send message that was sent
- * @return #GNUNET_OK if message is well-formed
- */
- static int
- check_add_address (void *cls,
- const struct GNUNET_TRANSPORT_AddAddressMessage *aam)
- {
- struct TransportClient *tc = cls;
- if (CT_COMMUNICATOR != tc->type)
- {
- GNUNET_break (0);
- return GNUNET_SYSERR;
- }
- GNUNET_MQ_check_zero_termination (aam);
- return GNUNET_OK;
- }
- /**
- * Ask peerstore to store our address.
- *
- * @param cls an `struct AddressListEntry *`
- */
- static void
- store_pi (void *cls);
- /**
- * Function called when peerstore is done storing our address.
- *
- * @param cls a `struct AddressListEntry`
- * @param success #GNUNET_YES if peerstore was successful
- */
- static void
- peerstore_store_own_cb (void *cls, int success)
- {
- struct AddressListEntry *ale = cls;
- ale->sc = NULL;
- if (GNUNET_YES != success)
- GNUNET_log (GNUNET_ERROR_TYPE_ERROR,
- "Failed to store our own address `%s' in peerstore!\n",
- ale->address);
- else
- GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
- "Successfully stored our own address `%s' in peerstore!\n",
- ale->address);
- /* refresh period is 1/4 of expiration time, that should be plenty
- without being excessive. */
- ale->st =
- GNUNET_SCHEDULER_add_delayed (GNUNET_TIME_relative_divide (ale->expiration,
- 4ULL),
- &store_pi,
- ale);
- }
- /**
- * Ask peerstore to store our address.
- *
- * @param cls an `struct AddressListEntry *`
- */
- static void
- store_pi (void *cls)
- {
- struct AddressListEntry *ale = cls;
- void *addr;
- size_t addr_len;
- struct GNUNET_TIME_Absolute expiration;
- ale->st = NULL;
- expiration = GNUNET_TIME_relative_to_absolute (ale->expiration);
- GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
- "Storing our address `%s' in peerstore until %s!\n",
- ale->address,
- GNUNET_STRINGS_absolute_time_to_string (expiration));
- GNUNET_HELLO_sign_address (ale->address,
- ale->nt,
- hello_mono_time,
- GST_my_private_key,
- &addr,
- &addr_len);
- ale->sc = GNUNET_PEERSTORE_store (peerstore,
- "transport",
- &GST_my_identity,
- GNUNET_PEERSTORE_TRANSPORT_HELLO_KEY,
- addr,
- addr_len,
- expiration,
- GNUNET_PEERSTORE_STOREOPTION_MULTIPLE,
- &peerstore_store_own_cb,
- ale);
- GNUNET_free (addr);
- if (NULL == ale->sc)
- {
- GNUNET_log (GNUNET_ERROR_TYPE_WARNING,
- "Failed to store our address `%s' with peerstore\n",
- ale->address);
- ale->st =
- GNUNET_SCHEDULER_add_delayed (GNUNET_TIME_UNIT_SECONDS, &store_pi, ale);
- }
- }
- /**
- * Address of our peer added. Process the request.
- *
- * @param cls the client
- * @param aam the send message that was sent
- */
- static void
- handle_add_address (void *cls,
- const struct GNUNET_TRANSPORT_AddAddressMessage *aam)
- {
- struct TransportClient *tc = cls;
- struct AddressListEntry *ale;
- size_t slen;
- /* 0-termination of &aam[1] was checked in #check_add_address */
- GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
- "Communicator added address `%s'!\n",
- (const char *) &aam[1]);
- slen = ntohs (aam->header.size) - sizeof(*aam);
- ale = GNUNET_malloc (sizeof(struct AddressListEntry) + slen);
- ale->tc = tc;
- ale->address = (const char *) &ale[1];
- ale->expiration = GNUNET_TIME_relative_ntoh (aam->expiration);
- ale->aid = aam->aid;
- ale->nt = (enum GNUNET_NetworkType) ntohl (aam->nt);
- memcpy (&ale[1], &aam[1], slen);
- GNUNET_CONTAINER_DLL_insert (tc->details.communicator.addr_head,
- tc->details.communicator.addr_tail,
- ale);
- ale->st = GNUNET_SCHEDULER_add_now (&store_pi, ale);
- GNUNET_SERVICE_client_continue (tc->client);
- }
- /**
- * Address of our peer deleted. Process the request.
- *
- * @param cls the client
- * @param dam the send message that was sent
- */
- static void
- handle_del_address (void *cls,
- const struct GNUNET_TRANSPORT_DelAddressMessage *dam)
- {
- struct TransportClient *tc = cls;
- struct AddressListEntry *alen;
- if (CT_COMMUNICATOR != tc->type)
- {
- GNUNET_break (0);
- GNUNET_SERVICE_client_drop (tc->client);
- return;
- }
- for (struct AddressListEntry *ale = tc->details.communicator.addr_head;
- NULL != ale;
- ale = alen)
- {
- alen = ale->next;
- if (dam->aid != ale->aid)
- continue;
- GNUNET_assert (ale->tc == tc);
- GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
- "Communicator deleted address `%s'!\n",
- ale->address);
- free_address_list_entry (ale);
- GNUNET_SERVICE_client_continue (tc->client);
- }
- GNUNET_break (0);
- GNUNET_SERVICE_client_drop (tc->client);
- }
- /**
- * Given an inbound message @a msg from a communicator @a cmc,
- * demultiplex it based on the type calling the right handler.
- *
- * @param cmc context for demultiplexing
- * @param msg message to demultiplex
- */
- static void
- demultiplex_with_cmc (struct CommunicatorMessageContext *cmc,
- const struct GNUNET_MessageHeader *msg);
- /**
- * Function called when we are done giving a message of a certain
- * size to CORE and should thus decrement the number of bytes of
- * RAM reserved for that peer's MQ.
- *
- * @param cls a `struct CoreSentContext`
- */
- static void
- core_env_sent_cb (void *cls)
- {
- struct CoreSentContext *ctx = cls;
- struct VirtualLink *vl = ctx->vl;
- if (NULL == vl)
- {
- /* lost the link in the meantime, ignore */
- GNUNET_free (ctx);
- return;
- }
- GNUNET_CONTAINER_DLL_remove (vl->csc_head, vl->csc_tail, ctx);
- GNUNET_assert (vl->incoming_fc_window_size_ram >= ctx->size);
- vl->incoming_fc_window_size_ram -= ctx->size;
- vl->incoming_fc_window_size_used += ctx->isize;
- consider_sending_fc (vl);
- GNUNET_free (ctx);
- }
- /**
- * Communicator gave us an unencapsulated message to pass as-is to
- * CORE. Process the request.
- *
- * @param cls a `struct CommunicatorMessageContext` (must call
- * #finish_cmc_handling() when done)
- * @param mh the message that was received
- */
- static void
- handle_raw_message (void *cls, const struct GNUNET_MessageHeader *mh)
- {
- struct CommunicatorMessageContext *cmc = cls;
- struct VirtualLink *vl;
- uint16_t size = ntohs (mh->size);
- int have_core;
- if ((size > UINT16_MAX - sizeof(struct InboundMessage)) ||
- (size < sizeof(struct GNUNET_MessageHeader)))
- {
- struct GNUNET_SERVICE_Client *client = cmc->tc->client;
- GNUNET_break (0);
- finish_cmc_handling (cmc);
- GNUNET_SERVICE_client_drop (client);
- return;
- }
- vl = lookup_virtual_link (&cmc->im.sender);
- if (NULL == vl)
- {
- /* FIXME: sender is giving us messages for CORE but we don't have
- the link up yet! I *suspect* this can happen right now (i.e.
- sender has verified us, but we didn't verify sender), but if
- we pass this on, CORE would be confused (link down, messages
- arrive). We should investigate more if this happens often,
- or in a persistent manner, and possibly do "something" about
- it. Thus logging as error for now. */GNUNET_break_op (0);
- GNUNET_STATISTICS_update (GST_stats,
- "# CORE messages droped (virtual link still down)",
- 1,
- GNUNET_NO);
- finish_cmc_handling (cmc);
- return;
- }
- if (vl->incoming_fc_window_size_ram > UINT_MAX - size)
- {
- GNUNET_STATISTICS_update (GST_stats,
- "# CORE messages droped (FC arithmetic overflow)",
- 1,
- GNUNET_NO);
- finish_cmc_handling (cmc);
- return;
- }
- if (vl->incoming_fc_window_size_ram + size > vl->available_fc_window_size)
- {
- GNUNET_STATISTICS_update (GST_stats,
- "# CORE messages droped (FC window overflow)",
- 1,
- GNUNET_NO);
- finish_cmc_handling (cmc);
- return;
- }
- /* Forward to all CORE clients */
- have_core = GNUNET_NO;
- for (struct TransportClient *tc = clients_head; NULL != tc; tc = tc->next)
- {
- struct GNUNET_MQ_Envelope *env;
- struct InboundMessage *im;
- struct CoreSentContext *ctx;
- if (CT_CORE != tc->type)
- continue;
- vl->incoming_fc_window_size_ram += size;
- env = GNUNET_MQ_msg_extra (im, size, GNUNET_MESSAGE_TYPE_TRANSPORT_RECV);
- ctx = GNUNET_new (struct CoreSentContext);
- ctx->vl = vl;
- ctx->size = size;
- ctx->isize = (GNUNET_NO == have_core) ? size : 0;
- have_core = GNUNET_YES;
- GNUNET_CONTAINER_DLL_insert (vl->csc_head, vl->csc_tail, ctx);
- GNUNET_MQ_notify_sent (env, &core_env_sent_cb, ctx);
- im->peer = cmc->im.sender;
- memcpy (&im[1], mh, size);
- GNUNET_MQ_send (tc->mq, env);
- vl->core_recv_window--;
- }
- if (GNUNET_NO == have_core)
- {
- GNUNET_log (GNUNET_ERROR_TYPE_WARNING,
- "Dropped message to CORE: no CORE client connected!\n");
- /* Nevertheless, count window as used, as it is from the
- perspective of the other peer! */
- vl->incoming_fc_window_size_used += size;
- /* TODO-M1 */
- finish_cmc_handling (cmc);
- return;
- }
- GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
- "Delivered message from %s of type %u to CORE\n",
- GNUNET_i2s (&cmc->im.sender),
- ntohs (mh->type));
- if (vl->core_recv_window > 0)
- {
- finish_cmc_handling (cmc);
- return;
- }
- /* Wait with calling #finish_cmc_handling(cmc) until the message
- was processed by CORE MQs (for CORE flow control)! */
- GNUNET_CONTAINER_DLL_insert (vl->cmc_head, vl->cmc_tail, cmc);
- }
- /**
- * Communicator gave us a fragment box. Check the message.
- *
- * @param cls a `struct CommunicatorMessageContext`
- * @param fb the send message that was sent
- * @return #GNUNET_YES if message is well-formed
- */
- static int
- check_fragment_box (void *cls, const struct TransportFragmentBoxMessage *fb)
- {
- uint16_t size = ntohs (fb->header.size);
- uint16_t bsize = size - sizeof(*fb);
- (void) cls;
- if (0 == bsize)
- {
- GNUNET_break_op (0);
- return GNUNET_SYSERR;
- }
- if (bsize + ntohs (fb->frag_off) > ntohs (fb->msg_size))
- {
- GNUNET_break_op (0);
- return GNUNET_SYSERR;
- }
- if (ntohs (fb->frag_off) >= ntohs (fb->msg_size))
- {
- GNUNET_break_op (0);
- return GNUNET_SYSERR;
- }
- return GNUNET_YES;
- }
- /**
- * Clean up an idle cummulative acknowledgement data structure.
- *
- * @param cls a `struct AcknowledgementCummulator *`
- */
- static void
- destroy_ack_cummulator (void *cls)
- {
- struct AcknowledgementCummulator *ac = cls;
- ac->task = NULL;
- GNUNET_assert (0 == ac->num_acks);
- GNUNET_assert (
- GNUNET_YES ==
- GNUNET_CONTAINER_multipeermap_remove (ack_cummulators, &ac->target, ac));
- GNUNET_free (ac);
- }
- /**
- * Do the transmission of a cummulative acknowledgement now.
- *
- * @param cls a `struct AcknowledgementCummulator *`
- */
- static void
- transmit_cummulative_ack_cb (void *cls)
- {
- struct AcknowledgementCummulator *ac = cls;
- char buf[sizeof(struct TransportReliabilityAckMessage)
- + ac->ack_counter
- * sizeof(struct TransportCummulativeAckPayloadP)] GNUNET_ALIGN;
- struct TransportReliabilityAckMessage *ack =
- (struct TransportReliabilityAckMessage *) buf;
- struct TransportCummulativeAckPayloadP *ap;
- ac->task = NULL;
- GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
- "Sending ACK with %u components to %s\n",
- ac->ack_counter,
- GNUNET_i2s (&ac->target));
- GNUNET_assert (0 < ac->ack_counter);
- ack->header.type = htons (GNUNET_MESSAGE_TYPE_TRANSPORT_RELIABILITY_ACK);
- ack->header.size =
- htons (sizeof(*ack)
- + ac->ack_counter * sizeof(struct TransportCummulativeAckPayloadP));
- ack->ack_counter = htonl (ac->ack_counter++);
- ap = (struct TransportCummulativeAckPayloadP *) &ack[1];
- for (unsigned int i = 0; i < ac->ack_counter; i++)
- {
- ap[i].ack_uuid = ac->ack_uuids[i].ack_uuid;
- ap[i].ack_delay = GNUNET_TIME_relative_hton (
- GNUNET_TIME_absolute_get_duration (ac->ack_uuids[i].receive_time));
- }
- route_control_message_without_fc (&ac->target, &ack->header, RMO_DV_ALLOWED);
- ac->num_acks = 0;
- ac->task = GNUNET_SCHEDULER_add_delayed (ACK_CUMMULATOR_TIMEOUT,
- &destroy_ack_cummulator,
- ac);
- }
- /**
- * Transmit an acknowledgement for @a ack_uuid to @a pid delaying
- * transmission by at most @a ack_delay.
- *
- * @param pid target peer
- * @param ack_uuid UUID to ack
- * @param max_delay how long can the ACK wait
- */
- static void
- cummulative_ack (const struct GNUNET_PeerIdentity *pid,
- const struct AcknowledgementUUIDP *ack_uuid,
- struct GNUNET_TIME_Absolute max_delay)
- {
- struct AcknowledgementCummulator *ac;
- GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
- "Scheduling ACK %s for transmission to %s\n",
- GNUNET_uuid2s (&ack_uuid->value),
- GNUNET_i2s (pid));
- ac = GNUNET_CONTAINER_multipeermap_get (ack_cummulators, pid);
- if (NULL == ac)
- {
- ac = GNUNET_new (struct AcknowledgementCummulator);
- ac->target = *pid;
- ac->min_transmission_time = max_delay;
- GNUNET_assert (GNUNET_YES ==
- GNUNET_CONTAINER_multipeermap_put (
- ack_cummulators,
- &ac->target,
- ac,
- GNUNET_CONTAINER_MULTIHASHMAPOPTION_UNIQUE_ONLY));
- }
- else
- {
- if (MAX_CUMMULATIVE_ACKS == ac->num_acks)
- {
- /* must run immediately, ack buffer full! */
- GNUNET_SCHEDULER_cancel (ac->task);
- transmit_cummulative_ack_cb (ac);
- }
- GNUNET_SCHEDULER_cancel (ac->task);
- ac->min_transmission_time =
- GNUNET_TIME_absolute_min (ac->min_transmission_time, max_delay);
- }
- GNUNET_assert (ac->num_acks < MAX_CUMMULATIVE_ACKS);
- ac->ack_uuids[ac->num_acks].receive_time = GNUNET_TIME_absolute_get ();
- ac->ack_uuids[ac->num_acks].ack_uuid = *ack_uuid;
- ac->num_acks++;
- ac->task = GNUNET_SCHEDULER_add_at (ac->min_transmission_time,
- &transmit_cummulative_ack_cb,
- ac);
- }
- /**
- * Closure for #find_by_message_uuid.
- */
- struct FindByMessageUuidContext
- {
- /**
- * UUID to look for.
- */
- struct MessageUUIDP message_uuid;
- /**
- * Set to the reassembly context if found.
- */
- struct ReassemblyContext *rc;
- };
- /**
- * Iterator called to find a reassembly context by the message UUID in the
- * multihashmap32.
- *
- * @param cls a `struct FindByMessageUuidContext`
- * @param key a key (unused)
- * @param value a `struct ReassemblyContext`
- * @return #GNUNET_YES if not found, #GNUNET_NO if found
- */
- static int
- find_by_message_uuid (void *cls, uint32_t key, void *value)
- {
- struct FindByMessageUuidContext *fc = cls;
- struct ReassemblyContext *rc = value;
- (void) key;
- if (0 == GNUNET_memcmp (&fc->message_uuid, &rc->msg_uuid))
- {
- fc->rc = rc;
- return GNUNET_NO;
- }
- return GNUNET_YES;
- }
- /**
- * Communicator gave us a fragment. Process the request.
- *
- * @param cls a `struct CommunicatorMessageContext` (must call
- * #finish_cmc_handling() when done)
- * @param fb the message that was received
- */
- static void
- handle_fragment_box (void *cls, const struct TransportFragmentBoxMessage *fb)
- {
- struct CommunicatorMessageContext *cmc = cls;
- struct Neighbour *n;
- struct ReassemblyContext *rc;
- const struct GNUNET_MessageHeader *msg;
- uint16_t msize;
- uint16_t fsize;
- uint16_t frag_off;
- char *target;
- struct GNUNET_TIME_Relative cdelay;
- struct FindByMessageUuidContext fc;
- n = lookup_neighbour (&cmc->im.sender);
- if (NULL == n)
- {
- struct GNUNET_SERVICE_Client *client = cmc->tc->client;
- GNUNET_break (0);
- finish_cmc_handling (cmc);
- GNUNET_SERVICE_client_drop (client);
- return;
- }
- if (NULL == n->reassembly_map)
- {
- n->reassembly_map = GNUNET_CONTAINER_multihashmap32_create (8);
- n->reassembly_heap =
- GNUNET_CONTAINER_heap_create (GNUNET_CONTAINER_HEAP_ORDER_MIN);
- n->reassembly_timeout_task =
- GNUNET_SCHEDULER_add_delayed (REASSEMBLY_EXPIRATION,
- &reassembly_cleanup_task,
- n);
- }
- msize = ntohs (fb->msg_size);
- fc.message_uuid = fb->msg_uuid;
- fc.rc = NULL;
- (void) GNUNET_CONTAINER_multihashmap32_get_multiple (n->reassembly_map,
- fb->msg_uuid.uuid,
- &find_by_message_uuid,
- &fc);
- if (NULL == (rc = fc.rc))
- {
- rc = GNUNET_malloc (sizeof(*rc) + msize /* reassembly payload buffer */
- + (msize + 7) / 8 * sizeof(uint8_t) /* bitfield */);
- rc->msg_uuid = fb->msg_uuid;
- rc->neighbour = n;
- rc->msg_size = msize;
- rc->reassembly_timeout =
- GNUNET_TIME_relative_to_absolute (REASSEMBLY_EXPIRATION);
- rc->last_frag = GNUNET_TIME_absolute_get ();
- rc->hn = GNUNET_CONTAINER_heap_insert (n->reassembly_heap,
- rc,
- rc->reassembly_timeout.abs_value_us);
- GNUNET_assert (GNUNET_OK ==
- GNUNET_CONTAINER_multihashmap32_put (
- n->reassembly_map,
- rc->msg_uuid.uuid,
- rc,
- GNUNET_CONTAINER_MULTIHASHMAPOPTION_MULTIPLE));
- target = (char *) &rc[1];
- rc->bitfield = (uint8_t *) (target + rc->msg_size);
- rc->msg_missing = rc->msg_size;
- GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
- "Received fragment at offset %u/%u from %s for NEW message %u\n",
- ntohs (fb->frag_off),
- msize,
- GNUNET_i2s (&cmc->im.sender),
- (unsigned int) fb->msg_uuid.uuid);
- }
- else
- {
- target = (char *) &rc[1];
- GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
- "Received fragment at offset %u/%u from %s for message %u\n",
- ntohs (fb->frag_off),
- msize,
- GNUNET_i2s (&cmc->im.sender),
- (unsigned int) fb->msg_uuid.uuid);
- }
- if (msize != rc->msg_size)
- {
- GNUNET_break (0);
- finish_cmc_handling (cmc);
- return;
- }
- /* reassemble */
- fsize = ntohs (fb->header.size) - sizeof(*fb);
- if (0 == fsize)
- {
- GNUNET_break (0);
- finish_cmc_handling (cmc);
- return;
- }
- frag_off = ntohs (fb->frag_off);
- if (frag_off + fsize > msize)
- {
- /* Fragment (plus fragment size) exceeds message size! */
- GNUNET_break_op (0);
- finish_cmc_handling (cmc);
- return;
- }
- memcpy (&target[frag_off], &fb[1], fsize);
- /* update bitfield and msg_missing */
- for (unsigned int i = frag_off; i < frag_off + fsize; i++)
- {
- if (0 == (rc->bitfield[i / 8] & (1 << (i % 8))))
- {
- rc->bitfield[i / 8] |= (1 << (i % 8));
- rc->msg_missing--;
- }
- }
- /* Compute cummulative ACK */
- cdelay = GNUNET_TIME_absolute_get_duration (rc->last_frag);
- cdelay = GNUNET_TIME_relative_multiply (cdelay, rc->msg_missing / fsize);
- if (0 == rc->msg_missing)
- cdelay = GNUNET_TIME_UNIT_ZERO;
- cummulative_ack (&cmc->im.sender,
- &fb->ack_uuid,
- GNUNET_TIME_relative_to_absolute (cdelay));
- rc->last_frag = GNUNET_TIME_absolute_get ();
- /* is reassembly complete? */
- if (0 != rc->msg_missing)
- {
- finish_cmc_handling (cmc);
- return;
- }
- /* reassembly is complete, verify result */
- msg = (const struct GNUNET_MessageHeader *) &rc[1];
- if (ntohs (msg->size) != rc->msg_size)
- {
- GNUNET_break (0);
- free_reassembly_context (rc);
- finish_cmc_handling (cmc);
- return;
- }
- /* successful reassembly */
- GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
- "Fragment reassembly complete for message %u\n",
- (unsigned int) fb->msg_uuid.uuid);
- /* FIXME: check that the resulting msg is NOT a
- DV Box or Reliability Box, as that is NOT allowed! */
- demultiplex_with_cmc (cmc, msg);
- /* FIXME-OPTIMIZE: really free here? Might be bad if fragments are still
- en-route and we forget that we finished this reassembly immediately!
- -> keep around until timeout?
- -> shorten timeout based on ACK? */
- free_reassembly_context (rc);
- }
- /**
- * Communicator gave us a reliability box. Check the message.
- *
- * @param cls a `struct CommunicatorMessageContext`
- * @param rb the send message that was sent
- * @return #GNUNET_YES if message is well-formed
- */
- static int
- check_reliability_box (void *cls,
- const struct TransportReliabilityBoxMessage *rb)
- {
- (void) cls;
- GNUNET_MQ_check_boxed_message (rb);
- return GNUNET_YES;
- }
- /**
- * Communicator gave us a reliability box. Process the request.
- *
- * @param cls a `struct CommunicatorMessageContext` (must call
- * #finish_cmc_handling() when done)
- * @param rb the message that was received
- */
- static void
- handle_reliability_box (void *cls,
- const struct TransportReliabilityBoxMessage *rb)
- {
- struct CommunicatorMessageContext *cmc = cls;
- const struct GNUNET_MessageHeader *inbox =
- (const struct GNUNET_MessageHeader *) &rb[1];
- struct GNUNET_TIME_Relative rtt;
- GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
- "Received reliability box from %s with UUID %s of type %u\n",
- GNUNET_i2s (&cmc->im.sender),
- GNUNET_uuid2s (&rb->ack_uuid.value),
- (unsigned int) ntohs (inbox->type));
- rtt = GNUNET_TIME_UNIT_SECONDS; /* FIXME: should base this on "RTT", but we
- do not really have an RTT for the
- * incoming* queue (should we have
- the sender add it to the rb message?) */
- cummulative_ack (
- &cmc->im.sender,
- &rb->ack_uuid,
- (0 == ntohl (rb->ack_countdown))
- ? GNUNET_TIME_UNIT_ZERO_ABS
- : GNUNET_TIME_relative_to_absolute (
- GNUNET_TIME_relative_divide (rtt, 8 /* FIXME: magic constant */)));
- /* continue with inner message */
- /* FIXME: check that inbox is NOT a DV Box, fragment or another
- reliability box (not allowed!) */
- demultiplex_with_cmc (cmc, inbox);
- }
- /**
- * Check if we have advanced to another age since the last time. If
- * so, purge ancient statistics (more than GOODPUT_AGING_SLOTS before
- * the current age)
- *
- * @param pd[in,out] data to update
- * @param age current age
- */
- static void
- update_pd_age (struct PerformanceData *pd, unsigned int age)
- {
- unsigned int sage;
- if (age == pd->last_age)
- return; /* nothing to do */
- sage = GNUNET_MAX (pd->last_age, age - 2 * GOODPUT_AGING_SLOTS);
- for (unsigned int i = sage; i <= age - GOODPUT_AGING_SLOTS; i++)
- {
- struct TransmissionHistoryEntry *the = &pd->the[i % GOODPUT_AGING_SLOTS];
- the->bytes_sent = 0;
- the->bytes_received = 0;
- }
- pd->last_age = age;
- }
- /**
- * Update @a pd based on the latest @a rtt and the number of bytes
- * that were confirmed to be successfully transmitted.
- *
- * @param pd[in,out] data to update
- * @param rtt latest round-trip time
- * @param bytes_transmitted_ok number of bytes receiver confirmed as received
- */
- static void
- update_performance_data (struct PerformanceData *pd,
- struct GNUNET_TIME_Relative rtt,
- uint16_t bytes_transmitted_ok)
- {
- uint64_t nval = rtt.rel_value_us;
- uint64_t oval = pd->aged_rtt.rel_value_us;
- unsigned int age = get_age ();
- struct TransmissionHistoryEntry *the = &pd->the[age % GOODPUT_AGING_SLOTS];
- if (oval == GNUNET_TIME_UNIT_FOREVER_REL.rel_value_us)
- pd->aged_rtt = rtt;
- else
- pd->aged_rtt.rel_value_us = (nval + 7 * oval) / 8;
- update_pd_age (pd, age);
- the->bytes_received += bytes_transmitted_ok;
- }
- /**
- * We have successfully transmitted data via @a q, update metrics.
- *
- * @param q queue to update
- * @param rtt round trip time observed
- * @param bytes_transmitted_ok number of bytes successfully transmitted
- */
- static void
- update_queue_performance (struct Queue *q,
- struct GNUNET_TIME_Relative rtt,
- uint16_t bytes_transmitted_ok)
- {
- update_performance_data (&q->pd, rtt, bytes_transmitted_ok);
- }
- /**
- * We have successfully transmitted data via @a dvh, update metrics.
- *
- * @param dvh distance vector path data to update
- * @param rtt round trip time observed
- * @param bytes_transmitted_ok number of bytes successfully transmitted
- */
- static void
- update_dvh_performance (struct DistanceVectorHop *dvh,
- struct GNUNET_TIME_Relative rtt,
- uint16_t bytes_transmitted_ok)
- {
- update_performance_data (&dvh->pd, rtt, bytes_transmitted_ok);
- }
- /**
- * We have completed transmission of @a pm, remove it from
- * the transmission queues (and if it is a fragment, continue
- * up the tree as necessary).
- *
- * @param pm pending message that was transmitted
- */
- static void
- completed_pending_message (struct PendingMessage *pm)
- {
- struct PendingMessage *pos;
- switch (pm->pmt)
- {
- case PMT_CORE:
- case PMT_RELIABILITY_BOX:
- /* Full message sent, we are done */
- client_send_response (pm);
- return;
- case PMT_FRAGMENT_BOX:
- /* Fragment sent over reliabile channel */
- free_fragment_tree (pm);
- pos = pm->frag_parent;
- GNUNET_CONTAINER_MDLL_remove (frag, pos->head_frag, pos->tail_frag, pm);
- GNUNET_free (pm);
- /* check if subtree is done */
- while ((NULL == pos->head_frag) && (pos->frag_off == pos->bytes_msg) &&
- (pos != pm))
- {
- pm = pos;
- pos = pm->frag_parent;
- GNUNET_CONTAINER_MDLL_remove (frag, pos->head_frag, pos->tail_frag, pm);
- GNUNET_free (pm);
- }
- /* Was this the last applicable fragmment? */
- if ((NULL == pos->head_frag) && (NULL == pos->frag_parent) &&
- (pos->frag_off == pos->bytes_msg))
- client_send_response (pos);
- return;
- case PMT_DV_BOX:
- GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
- "Completed transmission of message %llu (DV Box)\n",
- pm->logging_uuid);
- free_pending_message (pm);
- return;
- }
- }
- /**
- * The @a pa was acknowledged, process the acknowledgement.
- *
- * @param pa the pending acknowledgement that was satisfied
- * @param ack_delay artificial delay from cummulative acks created by the
- * other peer
- */
- static void
- handle_acknowledged (struct PendingAcknowledgement *pa,
- struct GNUNET_TIME_Relative ack_delay)
- {
- struct GNUNET_TIME_Relative delay;
- delay = GNUNET_TIME_absolute_get_duration (pa->transmission_time);
- if (delay.rel_value_us > ack_delay.rel_value_us)
- delay = GNUNET_TIME_UNIT_ZERO;
- else
- delay = GNUNET_TIME_relative_subtract (delay, ack_delay);
- if (NULL != pa->queue)
- update_queue_performance (pa->queue, delay, pa->message_size);
- if (NULL != pa->dvh)
- update_dvh_performance (pa->dvh, delay, pa->message_size);
- if (NULL != pa->pm)
- completed_pending_message (pa->pm);
- free_pending_acknowledgement (pa);
- }
- /**
- * Communicator gave us a reliability ack. Check it is well-formed.
- *
- * @param cls a `struct CommunicatorMessageContext` (unused)
- * @param ra the message that was received
- * @return #GNUNET_Ok if @a ra is well-formed
- */
- static int
- check_reliability_ack (void *cls,
- const struct TransportReliabilityAckMessage *ra)
- {
- unsigned int n_acks;
- (void) cls;
- n_acks = (ntohs (ra->header.size) - sizeof(*ra))
- / sizeof(struct TransportCummulativeAckPayloadP);
- if (0 == n_acks)
- {
- GNUNET_break_op (0);
- return GNUNET_SYSERR;
- }
- if ((ntohs (ra->header.size) - sizeof(*ra)) !=
- n_acks * sizeof(struct TransportCummulativeAckPayloadP))
- {
- GNUNET_break_op (0);
- return GNUNET_SYSERR;
- }
- return GNUNET_OK;
- }
- /**
- * Communicator gave us a reliability ack. Process the request.
- *
- * @param cls a `struct CommunicatorMessageContext` (must call
- * #finish_cmc_handling() when done)
- * @param ra the message that was received
- */
- static void
- handle_reliability_ack (void *cls,
- const struct TransportReliabilityAckMessage *ra)
- {
- struct CommunicatorMessageContext *cmc = cls;
- const struct TransportCummulativeAckPayloadP *ack;
- unsigned int n_acks;
- uint32_t ack_counter;
- n_acks = (ntohs (ra->header.size) - sizeof(*ra))
- / sizeof(struct TransportCummulativeAckPayloadP);
- ack = (const struct TransportCummulativeAckPayloadP *) &ra[1];
- for (unsigned int i = 0; i < n_acks; i++)
- {
- struct PendingAcknowledgement *pa =
- GNUNET_CONTAINER_multiuuidmap_get (pending_acks, &ack[i].ack_uuid.value);
- if (NULL == pa)
- {
- GNUNET_log (GNUNET_ERROR_TYPE_INFO,
- "Received ACK from %s with UUID %s which is unknown to us!\n",
- GNUNET_i2s (&cmc->im.sender),
- GNUNET_uuid2s (&ack[i].ack_uuid.value));
- GNUNET_STATISTICS_update (
- GST_stats,
- "# FRAGMENT_ACKS dropped, no matching pending message",
- 1,
- GNUNET_NO);
- continue;
- }
- GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
- "Received ACK from %s with UUID %s\n",
- GNUNET_i2s (&cmc->im.sender),
- GNUNET_uuid2s (&ack[i].ack_uuid.value));
- handle_acknowledged (pa, GNUNET_TIME_relative_ntoh (ack[i].ack_delay));
- }
- ack_counter = htonl (ra->ack_counter);
- (void) ack_counter; /* silence compiler warning for now */
- // FIXME-OPTIMIZE: track ACK losses based on ack_counter somewhere!
- // (DV and/or Neighbour?)
- finish_cmc_handling (cmc);
- }
- /**
- * Communicator gave us a backchannel encapsulation. Check the message.
- *
- * @param cls a `struct CommunicatorMessageContext`
- * @param be the send message that was sent
- * @return #GNUNET_YES if message is well-formed
- */
- static int
- check_backchannel_encapsulation (
- void *cls,
- const struct TransportBackchannelEncapsulationMessage *be)
- {
- uint16_t size = ntohs (be->header.size) - sizeof(*be);
- const struct GNUNET_MessageHeader *inbox =
- (const struct GNUNET_MessageHeader *) &be[1];
- const char *is;
- uint16_t isize;
- (void) cls;
- if (ntohs (inbox->size) >= size)
- {
- GNUNET_break_op (0);
- return GNUNET_SYSERR;
- }
- isize = ntohs (inbox->size);
- is = ((const char *) inbox) + isize;
- size -= isize;
- if ('\0' != is[size - 1])
- {
- GNUNET_break_op (0);
- return GNUNET_SYSERR;
- }
- return GNUNET_YES;
- }
- /**
- * Communicator gave us a backchannel encapsulation. Process the request.
- * (We are the destination of the backchannel here.)
- *
- * @param cls a `struct CommunicatorMessageContext` (must call
- * #finish_cmc_handling() when done)
- * @param be the message that was received
- */
- static void
- handle_backchannel_encapsulation (
- void *cls,
- const struct TransportBackchannelEncapsulationMessage *be)
- {
- struct CommunicatorMessageContext *cmc = cls;
- struct GNUNET_TRANSPORT_CommunicatorBackchannelIncoming *cbi;
- struct GNUNET_MQ_Envelope *env;
- struct TransportClient *tc;
- const struct GNUNET_MessageHeader *inbox =
- (const struct GNUNET_MessageHeader *) &be[1];
- uint16_t isize = ntohs (inbox->size);
- const char *target_communicator = ((const char *) inbox) + isize;
- /* Find client providing this communicator */
- for (tc = clients_head; NULL != tc; tc = tc->next)
- if ((CT_COMMUNICATOR == tc->type) &&
- (0 ==
- strcmp (tc->details.communicator.address_prefix, target_communicator)))
- break;
- if (NULL == tc)
- {
- char *stastr;
- GNUNET_asprintf (
- &stastr,
- "# Backchannel message dropped: target communicator `%s' unknown",
- target_communicator);
- GNUNET_STATISTICS_update (GST_stats, stastr, 1, GNUNET_NO);
- GNUNET_free (stastr);
- return;
- }
- /* Finally, deliver backchannel message to communicator */
- GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
- "Delivering backchannel message from %s of type %u to %s\n",
- GNUNET_i2s (&cmc->im.sender),
- ntohs (inbox->type),
- target_communicator);
- env = GNUNET_MQ_msg_extra (
- cbi,
- isize,
- GNUNET_MESSAGE_TYPE_TRANSPORT_COMMUNICATOR_BACKCHANNEL_INCOMING);
- cbi->pid = cmc->im.sender;
- memcpy (&cbi[1], inbox, isize);
- GNUNET_MQ_send (tc->mq, env);
- }
- /**
- * Task called when we should check if any of the DV paths
- * we have learned to a target are due for garbage collection.
- *
- * Collects stale paths, and possibly frees the entire DV
- * entry if no paths are left. Otherwise re-schedules itself.
- *
- * @param cls a `struct DistanceVector`
- */
- static void
- path_cleanup_cb (void *cls)
- {
- struct DistanceVector *dv = cls;
- struct DistanceVectorHop *pos;
- dv->timeout_task = NULL;
- while (NULL != (pos = dv->dv_head))
- {
- GNUNET_assert (dv == pos->dv);
- if (GNUNET_TIME_absolute_get_remaining (pos->timeout).rel_value_us > 0)
- break;
- free_distance_vector_hop (pos);
- }
- if (NULL == pos)
- {
- free_dv_route (dv);
- return;
- }
- dv->timeout_task =
- GNUNET_SCHEDULER_add_at (pos->timeout, &path_cleanup_cb, dv);
- }
- /**
- * The @a hop is a validated path to the respective target
- * peer and we should tell core about it -- and schedule
- * a job to revoke the state.
- *
- * @param hop a path to some peer that is the reason for activation
- */
- static void
- activate_core_visible_dv_path (struct DistanceVectorHop *hop)
- {
- struct DistanceVector *dv = hop->dv;
- struct VirtualLink *vl;
- vl = lookup_virtual_link (&dv->target);
- if (NULL != vl)
- {
- /* Link was already up, remember dv is also now available and we are done */
- vl->dv = dv;
- GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
- "Virtual link to %s could now also use DV!\n",
- GNUNET_i2s (&dv->target));
- return;
- }
- GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
- "Creating new virtual link to %s using DV!\n",
- GNUNET_i2s (&dv->target));
- vl = GNUNET_new (struct VirtualLink);
- vl->message_uuid_ctr =
- GNUNET_CRYPTO_random_u64 (GNUNET_CRYPTO_QUALITY_WEAK, UINT64_MAX);
- vl->target = dv->target;
- vl->dv = dv;
- dv->vl = vl;
- vl->core_recv_window = RECV_WINDOW_SIZE;
- vl->available_fc_window_size = DEFAULT_WINDOW_SIZE;
- vl->visibility_task =
- GNUNET_SCHEDULER_add_at (hop->path_valid_until, &check_link_down, vl);
- GNUNET_break (GNUNET_YES ==
- GNUNET_CONTAINER_multipeermap_put (
- links,
- &vl->target,
- vl,
- GNUNET_CONTAINER_MULTIHASHMAPOPTION_UNIQUE_ONLY));
- consider_sending_fc (vl);
- /* We lacked a confirmed connection to the target
- before, so tell CORE about it (finally!) */
- cores_send_connect_info (&dv->target);
- }
- /**
- * We have learned a @a path through the network to some other peer, add it to
- * our DV data structure (returning #GNUNET_YES on success).
- *
- * We do not add paths if we have a sufficient number of shorter
- * paths to this target already (returning #GNUNET_NO).
- *
- * We also do not add problematic paths, like those where we lack the first
- * hop in our neighbour list (i.e. due to a topology change) or where some
- * non-first hop is in our neighbour list (returning #GNUNET_SYSERR).
- *
- * @param path the path we learned, path[0] should be us,
- * and then path contains a valid path from us to
- * `path[path_len-1]` path[1] should be a direct neighbour (we should check!)
- * @param path_len number of entries on the @a path, at least three!
- * @param network_latency how long does the message take from us to
- * `path[path_len-1]`? set to "forever" if unknown
- * @param path_valid_until how long is this path considered validated? Maybe
- * be zero.
- * @return #GNUNET_YES on success,
- * #GNUNET_NO if we have better path(s) to the target
- * #GNUNET_SYSERR if the path is useless and/or invalid
- * (i.e. path[1] not a direct neighbour
- * or path[i+1] is a direct neighbour for i>0)
- */
- static int
- learn_dv_path (const struct GNUNET_PeerIdentity *path,
- unsigned int path_len,
- struct GNUNET_TIME_Relative network_latency,
- struct GNUNET_TIME_Absolute path_valid_until)
- {
- struct DistanceVectorHop *hop;
- struct DistanceVector *dv;
- struct Neighbour *next_hop;
- unsigned int shorter_distance;
- if (path_len < 3)
- {
- /* what a boring path! not allowed! */
- GNUNET_break (0);
- return GNUNET_SYSERR;
- }
- GNUNET_assert (0 == GNUNET_memcmp (&GST_my_identity, &path[0]));
- next_hop = lookup_neighbour (&path[1]);
- if (NULL == next_hop)
- {
- /* next hop must be a neighbour, otherwise this whole thing is useless! */
- GNUNET_break (0);
- return GNUNET_SYSERR;
- }
- for (unsigned int i = 2; i < path_len; i++)
- if (NULL != lookup_neighbour (&path[i]))
- {
- /* Useless path: we have a direct connection to some hop
- in the middle of the path, so this one is not even
- terribly useful for redundancy */
- GNUNET_log (GNUNET_ERROR_TYPE_INFO,
- "Path of %u hops useless: directly link to hop %u (%s)\n",
- path_len,
- i,
- GNUNET_i2s (&path[i]));
- GNUNET_STATISTICS_update (GST_stats,
- "# Useless DV path ignored: hop is neighbour",
- 1,
- GNUNET_NO);
- return GNUNET_SYSERR;
- }
- dv = GNUNET_CONTAINER_multipeermap_get (dv_routes, &path[path_len - 1]);
- if (NULL == dv)
- {
- dv = GNUNET_new (struct DistanceVector);
- dv->target = path[path_len - 1];
- dv->timeout_task = GNUNET_SCHEDULER_add_delayed (DV_PATH_VALIDITY_TIMEOUT,
- &path_cleanup_cb,
- dv);
- GNUNET_assert (GNUNET_OK ==
- GNUNET_CONTAINER_multipeermap_put (
- dv_routes,
- &dv->target,
- dv,
- GNUNET_CONTAINER_MULTIHASHMAPOPTION_UNIQUE_ONLY));
- }
- /* Check if we have this path already! */
- shorter_distance = 0;
- for (struct DistanceVectorHop *pos = dv->dv_head; NULL != pos;
- pos = pos->next_dv)
- {
- if (pos->distance < path_len - 2)
- shorter_distance++;
- /* Note that the distances in 'pos' excludes us (path[0]) and
- the next_hop (path[1]), so we need to subtract two
- and check next_hop explicitly */
- if ((pos->distance == path_len - 2) && (pos->next_hop == next_hop))
- {
- int match = GNUNET_YES;
- for (unsigned int i = 0; i < pos->distance; i++)
- {
- if (0 != GNUNET_memcmp (&pos->path[i], &path[i + 2]))
- {
- match = GNUNET_NO;
- break;
- }
- }
- if (GNUNET_YES == match)
- {
- struct GNUNET_TIME_Relative last_timeout;
- /* Re-discovered known path, update timeout */
- GNUNET_STATISTICS_update (GST_stats,
- "# Known DV path refreshed",
- 1,
- GNUNET_NO);
- last_timeout = GNUNET_TIME_absolute_get_remaining (pos->timeout);
- pos->timeout =
- GNUNET_TIME_relative_to_absolute (DV_PATH_VALIDITY_TIMEOUT);
- pos->path_valid_until =
- GNUNET_TIME_absolute_max (pos->path_valid_until, path_valid_until);
- GNUNET_CONTAINER_MDLL_remove (dv, dv->dv_head, dv->dv_tail, pos);
- GNUNET_CONTAINER_MDLL_insert (dv, dv->dv_head, dv->dv_tail, pos);
- if (0 <
- GNUNET_TIME_absolute_get_remaining (path_valid_until).rel_value_us)
- activate_core_visible_dv_path (pos);
- if (last_timeout.rel_value_us <
- GNUNET_TIME_relative_subtract (DV_PATH_VALIDITY_TIMEOUT,
- DV_PATH_DISCOVERY_FREQUENCY)
- .rel_value_us)
- {
- /* Some peer send DV learn messages too often, we are learning
- the same path faster than it would be useful; do not forward! */
- GNUNET_log (GNUNET_ERROR_TYPE_INFO,
- "Rediscovered path too quickly, not forwarding further\n");
- return GNUNET_NO;
- }
- GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
- "Refreshed known path to %s, forwarding further\n",
- GNUNET_i2s (&dv->target));
- return GNUNET_YES;
- }
- }
- }
- /* Count how many shorter paths we have (incl. direct
- neighbours) before simply giving up on this one! */
- if (shorter_distance >= MAX_DV_PATHS_TO_TARGET)
- {
- /* We have a shorter path already! */
- GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
- "Have many shorter DV paths %s, not forwarding further\n",
- GNUNET_i2s (&dv->target));
- return GNUNET_NO;
- }
- /* create new DV path entry */
- GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
- "Discovered new DV path to %s\n",
- GNUNET_i2s (&dv->target));
- hop = GNUNET_malloc (sizeof(struct DistanceVectorHop)
- + sizeof(struct GNUNET_PeerIdentity) * (path_len - 2));
- hop->next_hop = next_hop;
- hop->dv = dv;
- hop->path = (const struct GNUNET_PeerIdentity *) &hop[1];
- memcpy (&hop[1],
- &path[2],
- sizeof(struct GNUNET_PeerIdentity) * (path_len - 2));
- hop->timeout = GNUNET_TIME_relative_to_absolute (DV_PATH_VALIDITY_TIMEOUT);
- hop->path_valid_until = path_valid_until;
- hop->distance = path_len - 2;
- hop->pd.aged_rtt = network_latency;
- GNUNET_CONTAINER_MDLL_insert (dv, dv->dv_head, dv->dv_tail, hop);
- GNUNET_CONTAINER_MDLL_insert (neighbour,
- next_hop->dv_head,
- next_hop->dv_tail,
- hop);
- if (0 < GNUNET_TIME_absolute_get_remaining (path_valid_until).rel_value_us)
- activate_core_visible_dv_path (hop);
- return GNUNET_YES;
- }
- /**
- * Communicator gave us a DV learn message. Check the message.
- *
- * @param cls a `struct CommunicatorMessageContext`
- * @param dvl the send message that was sent
- * @return #GNUNET_YES if message is well-formed
- */
- static int
- check_dv_learn (void *cls, const struct TransportDVLearnMessage *dvl)
- {
- uint16_t size = ntohs (dvl->header.size);
- uint16_t num_hops = ntohs (dvl->num_hops);
- const struct DVPathEntryP *hops = (const struct DVPathEntryP *) &dvl[1];
- (void) cls;
- if (size != sizeof(*dvl) + num_hops * sizeof(struct DVPathEntryP))
- {
- GNUNET_break_op (0);
- return GNUNET_SYSERR;
- }
- if (num_hops > MAX_DV_HOPS_ALLOWED)
- {
- GNUNET_break_op (0);
- return GNUNET_SYSERR;
- }
- for (unsigned int i = 0; i < num_hops; i++)
- {
- if (0 == GNUNET_memcmp (&dvl->initiator, &hops[i].hop))
- {
- GNUNET_break_op (0);
- return GNUNET_SYSERR;
- }
- if (0 == GNUNET_memcmp (&GST_my_identity, &hops[i].hop))
- {
- GNUNET_break_op (0);
- return GNUNET_SYSERR;
- }
- }
- return GNUNET_YES;
- }
- /**
- * Build and forward a DV learn message to @a next_hop.
- *
- * @param next_hop peer to send the message to
- * @param msg message received
- * @param bi_history bitmask specifying hops on path that were bidirectional
- * @param nhops length of the @a hops array
- * @param hops path the message traversed so far
- * @param in_time when did we receive the message, used to calculate network
- * delay
- */
- static void
- forward_dv_learn (const struct GNUNET_PeerIdentity *next_hop,
- const struct TransportDVLearnMessage *msg,
- uint16_t bi_history,
- uint16_t nhops,
- const struct DVPathEntryP *hops,
- struct GNUNET_TIME_Absolute in_time)
- {
- struct DVPathEntryP *dhops;
- char buf[sizeof(struct TransportDVLearnMessage)
- + (nhops + 1) * sizeof(struct DVPathEntryP)] GNUNET_ALIGN;
- struct TransportDVLearnMessage *fwd = (struct TransportDVLearnMessage *) buf;
- struct GNUNET_TIME_Relative nnd;
- /* compute message for forwarding */
- GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
- "Forwarding DV learn message originating from %s to %s\n",
- GNUNET_i2s (&msg->initiator),
- GNUNET_i2s2 (next_hop));
- GNUNET_assert (nhops < MAX_DV_HOPS_ALLOWED);
- fwd->header.type = htons (GNUNET_MESSAGE_TYPE_TRANSPORT_DV_LEARN);
- fwd->header.size = htons (sizeof(struct TransportDVLearnMessage)
- + (nhops + 1) * sizeof(struct DVPathEntryP));
- fwd->num_hops = htons (nhops + 1);
- fwd->bidirectional = htons (bi_history);
- nnd = GNUNET_TIME_relative_add (GNUNET_TIME_absolute_get_duration (in_time),
- GNUNET_TIME_relative_ntoh (
- msg->non_network_delay));
- fwd->non_network_delay = GNUNET_TIME_relative_hton (nnd);
- fwd->init_sig = msg->init_sig;
- fwd->initiator = msg->initiator;
- fwd->challenge = msg->challenge;
- dhops = (struct DVPathEntryP *) &fwd[1];
- GNUNET_memcpy (dhops, hops, sizeof(struct DVPathEntryP) * nhops);
- dhops[nhops].hop = GST_my_identity;
- {
- struct DvHopPS dhp = {
- .purpose.purpose = htonl (GNUNET_SIGNATURE_PURPOSE_TRANSPORT_DV_HOP),
- .purpose.size = htonl (sizeof(dhp)),
- .pred = dhops[nhops - 1].hop,
- .succ = *next_hop,
- .challenge = msg->challenge
- };
- GNUNET_CRYPTO_eddsa_sign (GST_my_private_key,
- &dhp,
- &dhops[nhops].hop_sig);
- }
- route_control_message_without_fc (next_hop,
- &fwd->header,
- RMO_UNCONFIRMED_ALLOWED);
- }
- /**
- * Check signature of type #GNUNET_SIGNATURE_PURPOSE_TRANSPORT_DV_INITIATOR
- *
- * @param sender_monotonic_time monotonic time of the initiator
- * @param init the signer
- * @param challenge the challenge that was signed
- * @param init_sig signature presumably by @a init
- * @return #GNUNET_OK if the signature is valid
- */
- static int
- validate_dv_initiator_signature (
- struct GNUNET_TIME_AbsoluteNBO sender_monotonic_time,
- const struct GNUNET_PeerIdentity *init,
- const struct ChallengeNonceP *challenge,
- const struct GNUNET_CRYPTO_EddsaSignature *init_sig)
- {
- struct DvInitPS ip = { .purpose.purpose = htonl (
- GNUNET_SIGNATURE_PURPOSE_TRANSPORT_DV_INITIATOR),
- .purpose.size = htonl (sizeof(ip)),
- .monotonic_time = sender_monotonic_time,
- .challenge = *challenge };
- if (
- GNUNET_OK !=
- GNUNET_CRYPTO_eddsa_verify (GNUNET_SIGNATURE_PURPOSE_TRANSPORT_DV_INITIATOR,
- &ip,
- init_sig,
- &init->public_key))
- {
- GNUNET_break_op (0);
- return GNUNET_SYSERR;
- }
- return GNUNET_OK;
- }
- /**
- * Closure for #dv_neighbour_selection and #dv_neighbour_transmission.
- */
- struct NeighbourSelectionContext
- {
- /**
- * Original message we received.
- */
- const struct TransportDVLearnMessage *dvl;
- /**
- * The hops taken.
- */
- const struct DVPathEntryP *hops;
- /**
- * Time we received the message.
- */
- struct GNUNET_TIME_Absolute in_time;
- /**
- * Offsets of the selected peers.
- */
- uint32_t selections[MAX_DV_DISCOVERY_SELECTION];
- /**
- * Number of peers eligible for selection.
- */
- unsigned int num_eligible;
- /**
- * Number of peers that were selected for forwarding.
- */
- unsigned int num_selections;
- /**
- * Number of hops in @e hops
- */
- uint16_t nhops;
- /**
- * Bitmap of bidirectional connections encountered.
- */
- uint16_t bi_history;
- };
- /**
- * Function called for each neighbour during #handle_dv_learn.
- *
- * @param cls a `struct NeighbourSelectionContext *`
- * @param pid identity of the peer
- * @param value a `struct Neighbour`
- * @return #GNUNET_YES (always)
- */
- static int
- dv_neighbour_selection (void *cls,
- const struct GNUNET_PeerIdentity *pid,
- void *value)
- {
- struct NeighbourSelectionContext *nsc = cls;
- (void) value;
- if (0 == GNUNET_memcmp (pid, &nsc->dvl->initiator))
- return GNUNET_YES; /* skip initiator */
- for (unsigned int i = 0; i < nsc->nhops; i++)
- if (0 == GNUNET_memcmp (pid, &nsc->hops[i].hop))
- return GNUNET_YES;
- /* skip peers on path */
- nsc->num_eligible++;
- return GNUNET_YES;
- }
- /**
- * Function called for each neighbour during #handle_dv_learn.
- * We call #forward_dv_learn() on the neighbour(s) selected
- * during #dv_neighbour_selection().
- *
- * @param cls a `struct NeighbourSelectionContext *`
- * @param pid identity of the peer
- * @param value a `struct Neighbour`
- * @return #GNUNET_YES (always)
- */
- static int
- dv_neighbour_transmission (void *cls,
- const struct GNUNET_PeerIdentity *pid,
- void *value)
- {
- struct NeighbourSelectionContext *nsc = cls;
- (void) value;
- if (0 == GNUNET_memcmp (pid, &nsc->dvl->initiator))
- return GNUNET_YES; /* skip initiator */
- for (unsigned int i = 0; i < nsc->nhops; i++)
- if (0 == GNUNET_memcmp (pid, &nsc->hops[i].hop))
- return GNUNET_YES;
- /* skip peers on path */
- for (unsigned int i = 0; i < nsc->num_selections; i++)
- {
- if (nsc->selections[i] == nsc->num_eligible)
- {
- forward_dv_learn (pid,
- nsc->dvl,
- nsc->bi_history,
- nsc->nhops,
- nsc->hops,
- nsc->in_time);
- break;
- }
- }
- nsc->num_eligible++;
- return GNUNET_YES;
- }
- /**
- * Computes the number of neighbours we should forward a DVInit
- * message to given that it has so far taken @a hops_taken hops
- * though the network and that the number of neighbours we have
- * in total is @a neighbour_count, out of which @a eligible_count
- * are not yet on the path.
- *
- * NOTE: technically we might want to include NSE in the formula to
- * get a better grip on the overall network size. However, for now
- * using NSE here would create a dependency issue in the build system.
- * => Left for later, hardcoded to 50 for now.
- *
- * The goal of the fomula is that we want to reach a total of LOG(NSE)
- * peers via DV (`target_total`). We want the reach to be spread out
- * over various distances to the origin, with a bias towards shorter
- * distances.
- *
- * We make the strong assumption that the network topology looks
- * "similar" at other hops, in particular the @a neighbour_count
- * should be comparable at other hops.
- *
- * If the local neighbourhood is densely connected, we expect that @a
- * eligible_count is close to @a neighbour_count minus @a hops_taken
- * as a lot of the path is already known. In that case, we should
- * forward to few(er) peers to try to find a path out of the
- * neighbourhood. OTOH, if @a eligible_count is close to @a
- * neighbour_count, we should forward to many peers as we are either
- * still close to the origin (i.e. @a hops_taken is small) or because
- * we managed to get beyond a local cluster. We express this as
- * the `boost_factor` using the square of the fraction of eligible
- * neighbours (so if only 50% are eligible, we boost by 1/4, but if
- * 99% are eligible, the 'boost' will be almost 1).
- *
- * Second, the more hops we have taken, the larger the problem of an
- * exponential traffic explosion gets. So we take the `target_total`,
- * and compute our degree such that at each distance d 2^{-d} peers
- * are selected (corrected by the `boost_factor`).
- *
- * @param hops_taken number of hops DVInit has travelled so far
- * @param neighbour_count number of neighbours we have in total
- * @param eligible_count number of neighbours we could in
- * theory forward to
- */
- static unsigned int
- calculate_fork_degree (unsigned int hops_taken,
- unsigned int neighbour_count,
- unsigned int eligible_count)
- {
- double target_total = 50.0; /* FIXME: use LOG(NSE)? */
- double eligible_ratio =
- ((double) eligible_count) / ((double) neighbour_count);
- double boost_factor = eligible_ratio * eligible_ratio;
- unsigned int rnd;
- double left;
- if (hops_taken >= 64)
- {
- GNUNET_break (0);
- return 0; /* precaution given bitshift below */
- }
- for (unsigned int i = 1; i < hops_taken; i++)
- {
- /* For each hop, subtract the expected number of targets
- reached at distance d (so what remains divided by 2^d) */
- target_total -= (target_total * boost_factor / (1LLU << i));
- }
- rnd =
- (unsigned int) floor (target_total * boost_factor / (1LLU << hops_taken));
- /* round up or down probabilistically depending on how close we were
- when floor()ing to rnd */
- left = target_total - (double) rnd;
- if (UINT32_MAX * left >
- GNUNET_CRYPTO_random_u64 (GNUNET_CRYPTO_QUALITY_WEAK, UINT32_MAX))
- rnd++; /* round up */
- GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
- "Forwarding DV learn message of %u hops %u(/%u/%u) times\n",
- hops_taken,
- rnd,
- eligible_count,
- neighbour_count);
- return rnd;
- }
- /**
- * Function called when peerstore is done storing a DV monotonic time.
- *
- * @param cls a `struct Neighbour`
- * @param success #GNUNET_YES if peerstore was successful
- */
- static void
- neighbour_store_dvmono_cb (void *cls, int success)
- {
- struct Neighbour *n = cls;
- n->sc = NULL;
- if (GNUNET_YES != success)
- GNUNET_log (GNUNET_ERROR_TYPE_ERROR,
- "Failed to store other peer's monotonic time in peerstore!\n");
- }
- /**
- * Communicator gave us a DV learn message. Process the request.
- *
- * @param cls a `struct CommunicatorMessageContext` (must call
- * #finish_cmc_handling() when done)
- * @param dvl the message that was received
- */
- static void
- handle_dv_learn (void *cls, const struct TransportDVLearnMessage *dvl)
- {
- struct CommunicatorMessageContext *cmc = cls;
- enum GNUNET_TRANSPORT_CommunicatorCharacteristics cc;
- int bi_hop;
- uint16_t nhops;
- uint16_t bi_history;
- const struct DVPathEntryP *hops;
- int do_fwd;
- int did_initiator;
- struct GNUNET_TIME_Absolute in_time;
- struct Neighbour *n;
- nhops = ntohs (dvl->bidirectional); /* 0 = sender is initiator */
- bi_history = ntohs (dvl->bidirectional);
- hops = (const struct DVPathEntryP *) &dvl[1];
- if (0 == nhops)
- {
- /* sanity check */
- if (0 != GNUNET_memcmp (&dvl->initiator, &cmc->im.sender))
- {
- GNUNET_break (0);
- finish_cmc_handling (cmc);
- return;
- }
- }
- else
- {
- /* sanity check */
- if (0 != GNUNET_memcmp (&hops[nhops - 1].hop, &cmc->im.sender))
- {
- GNUNET_break (0);
- finish_cmc_handling (cmc);
- return;
- }
- }
- GNUNET_assert (CT_COMMUNICATOR == cmc->tc->type);
- cc = cmc->tc->details.communicator.cc;
- bi_hop = (GNUNET_TRANSPORT_CC_RELIABLE ==
- cc); // FIXME: add bi-directional flag to cc?
- in_time = GNUNET_TIME_absolute_get ();
- /* continue communicator here, everything else can happen asynchronous! */
- finish_cmc_handling (cmc);
- n = lookup_neighbour (&dvl->initiator);
- if (NULL != n)
- {
- if ((n->dv_monotime_available == GNUNET_YES) &&
- (GNUNET_TIME_absolute_ntoh (dvl->monotonic_time).abs_value_us <
- n->last_dv_learn_monotime.abs_value_us))
- {
- GNUNET_STATISTICS_update (GST_stats,
- "# DV learn discarded due to time travel",
- 1,
- GNUNET_NO);
- return;
- }
- if (GNUNET_OK != validate_dv_initiator_signature (dvl->monotonic_time,
- &dvl->initiator,
- &dvl->challenge,
- &dvl->init_sig))
- {
- GNUNET_break_op (0);
- return;
- }
- n->last_dv_learn_monotime = GNUNET_TIME_absolute_ntoh (dvl->monotonic_time);
- if (GNUNET_YES == n->dv_monotime_available)
- {
- if (NULL != n->sc)
- GNUNET_PEERSTORE_store_cancel (n->sc);
- n->sc =
- GNUNET_PEERSTORE_store (peerstore,
- "transport",
- &dvl->initiator,
- GNUNET_PEERSTORE_TRANSPORT_DVLEARN_MONOTIME,
- &dvl->monotonic_time,
- sizeof(dvl->monotonic_time),
- GNUNET_TIME_UNIT_FOREVER_ABS,
- GNUNET_PEERSTORE_STOREOPTION_REPLACE,
- &neighbour_store_dvmono_cb,
- n);
- }
- }
- /* OPTIMIZE-FIXME: asynchronously (!) verify signatures!,
- If signature verification load too high, implement random drop strategy */
- for (unsigned int i = 0; i < nhops; i++)
- {
- struct DvHopPS dhp = { .purpose.purpose =
- htonl (GNUNET_SIGNATURE_PURPOSE_TRANSPORT_DV_HOP),
- .purpose.size = htonl (sizeof(dhp)),
- .pred = (0 == i) ? dvl->initiator : hops[i - 1].hop,
- .succ = (nhops == i + 1) ? GST_my_identity
- : hops[i + 1].hop,
- .challenge = dvl->challenge };
- if (GNUNET_OK !=
- GNUNET_CRYPTO_eddsa_verify (GNUNET_SIGNATURE_PURPOSE_TRANSPORT_DV_HOP,
- &dhp,
- &hops[i].hop_sig,
- &hops[i].hop.public_key))
- {
- GNUNET_break_op (0);
- return;
- }
- }
- if (GNUNET_EXTRA_LOGGING > 0)
- {
- char *path;
- path = GNUNET_strdup (GNUNET_i2s (&dvl->initiator));
- for (unsigned int i = 0; i < nhops; i++)
- {
- char *tmp;
- GNUNET_asprintf (&tmp,
- "%s%s%s",
- path,
- (bi_history & (1 << (nhops - i))) ? "<->" : "-->",
- GNUNET_i2s (&hops[i].hop));
- GNUNET_free (path);
- path = tmp;
- }
- GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
- "Received DVInit via %s%s%s\n",
- path,
- bi_hop ? "<->" : "-->",
- GNUNET_i2s (&GST_my_identity));
- GNUNET_free (path);
- }
- do_fwd = GNUNET_YES;
- if (0 == GNUNET_memcmp (&GST_my_identity, &dvl->initiator))
- {
- struct GNUNET_PeerIdentity path[nhops + 1];
- struct GNUNET_TIME_Relative host_latency_sum;
- struct GNUNET_TIME_Relative latency;
- struct GNUNET_TIME_Relative network_latency;
- /* We initiated this, learn the forward path! */
- path[0] = GST_my_identity;
- path[1] = hops[0].hop;
- host_latency_sum = GNUNET_TIME_relative_ntoh (dvl->non_network_delay);
- // Need also something to lookup initiation time
- // to compute RTT! -> add RTT argument here?
- latency = GNUNET_TIME_UNIT_FOREVER_REL; // FIXME: initialize properly
- // (based on dvl->challenge, we can identify time of origin!)
- network_latency = GNUNET_TIME_relative_subtract (latency, host_latency_sum);
- /* assumption: latency on all links is the same */
- network_latency = GNUNET_TIME_relative_divide (network_latency, nhops);
- for (unsigned int i = 2; i <= nhops; i++)
- {
- struct GNUNET_TIME_Relative ilat;
- /* assumption: linear latency increase per hop */
- ilat = GNUNET_TIME_relative_multiply (network_latency, i);
- path[i] = hops[i - 1].hop;
- GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
- "Learned path with %u hops to %s with latency %s\n",
- i,
- GNUNET_i2s (&path[i]),
- GNUNET_STRINGS_relative_time_to_string (ilat, GNUNET_YES));
- learn_dv_path (path,
- i,
- ilat,
- GNUNET_TIME_relative_to_absolute (
- ADDRESS_VALIDATION_LIFETIME));
- }
- /* as we initiated, do not forward again (would be circular!) */
- do_fwd = GNUNET_NO;
- return;
- }
- if (bi_hop)
- {
- /* last hop was bi-directional, we could learn something here! */
- struct GNUNET_PeerIdentity path[nhops + 2];
- path[0] = GST_my_identity;
- path[1] = hops[nhops - 1].hop; /* direct neighbour == predecessor! */
- for (unsigned int i = 0; i < nhops; i++)
- {
- int iret;
- if (0 == (bi_history & (1 << i)))
- break; /* i-th hop not bi-directional, stop learning! */
- if (i == nhops - 1)
- {
- path[i + 2] = dvl->initiator;
- }
- else
- {
- path[i + 2] = hops[nhops - i - 2].hop;
- }
- GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
- "Learned inverse path with %u hops to %s\n",
- i + 1,
- GNUNET_i2s (&path[i + 2]));
- iret = learn_dv_path (path,
- i + 2,
- GNUNET_TIME_UNIT_FOREVER_REL,
- GNUNET_TIME_UNIT_ZERO_ABS);
- if (GNUNET_SYSERR == iret)
- {
- /* path invalid or too long to be interesting for US, thus should also
- not be interesting to our neighbours, cut path when forwarding to
- 'i' hops, except of course for the one that goes back to the
- initiator */
- GNUNET_STATISTICS_update (GST_stats,
- "# DV learn not forwarded due invalidity of path",
- 1,
- GNUNET_NO);
- do_fwd = GNUNET_NO;
- break;
- }
- if ((GNUNET_NO == iret) && (nhops == i + 1))
- {
- /* we have better paths, and this is the longest target,
- so there cannot be anything interesting later */
- GNUNET_STATISTICS_update (GST_stats,
- "# DV learn not forwarded, got better paths",
- 1,
- GNUNET_NO);
- do_fwd = GNUNET_NO;
- break;
- }
- }
- }
- if (MAX_DV_HOPS_ALLOWED == nhops)
- {
- /* At limit, we're out of here! */
- finish_cmc_handling (cmc);
- return;
- }
- /* Forward to initiator, if path non-trivial and possible */
- bi_history = (bi_history << 1) | (bi_hop ? 1 : 0);
- did_initiator = GNUNET_NO;
- if ((1 < nhops) &&
- (GNUNET_YES ==
- GNUNET_CONTAINER_multipeermap_contains (neighbours, &dvl->initiator)))
- {
- /* send back to origin! */
- GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
- "Sending DVL back to initiator %s\n",
- GNUNET_i2s (&dvl->initiator));
- forward_dv_learn (&dvl->initiator, dvl, bi_history, nhops, hops, in_time);
- did_initiator = GNUNET_YES;
- }
- /* We forward under two conditions: either we still learned something
- ourselves (do_fwd), or the path was darn short and thus the initiator is
- likely to still be very interested in this (and we did NOT already
- send it back to the initiator) */
- if ((do_fwd) || ((nhops < MIN_DV_PATH_LENGTH_FOR_INITIATOR) &&
- (GNUNET_NO == did_initiator)))
- {
- /* Pick random neighbours that are not yet on the path */
- struct NeighbourSelectionContext nsc;
- unsigned int n_cnt;
- n_cnt = GNUNET_CONTAINER_multipeermap_size (neighbours);
- nsc.nhops = nhops;
- nsc.dvl = dvl;
- nsc.bi_history = bi_history;
- nsc.hops = hops;
- nsc.in_time = in_time;
- nsc.num_eligible = 0;
- GNUNET_CONTAINER_multipeermap_iterate (neighbours,
- &dv_neighbour_selection,
- &nsc);
- if (0 == nsc.num_eligible)
- return; /* done here, cannot forward to anyone else */
- nsc.num_selections = calculate_fork_degree (nhops, n_cnt, nsc.num_eligible);
- nsc.num_selections =
- GNUNET_MIN (MAX_DV_DISCOVERY_SELECTION, nsc.num_selections);
- GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
- "Forwarding DVL to %u other peers\n",
- nsc.num_selections);
- for (unsigned int i = 0; i < nsc.num_selections; i++)
- nsc.selections[i] =
- (nsc.num_selections == n_cnt)
- ? i /* all were selected, avoid collisions by chance */
- : GNUNET_CRYPTO_random_u32 (GNUNET_CRYPTO_QUALITY_WEAK, n_cnt);
- nsc.num_eligible = 0;
- GNUNET_CONTAINER_multipeermap_iterate (neighbours,
- &dv_neighbour_transmission,
- &nsc);
- }
- }
- /**
- * Communicator gave us a DV box. Check the message.
- *
- * @param cls a `struct CommunicatorMessageContext`
- * @param dvb the send message that was sent
- * @return #GNUNET_YES if message is well-formed
- */
- static int
- check_dv_box (void *cls, const struct TransportDVBoxMessage *dvb)
- {
- uint16_t size = ntohs (dvb->header.size);
- uint16_t num_hops = ntohs (dvb->num_hops);
- const struct GNUNET_PeerIdentity *hops =
- (const struct GNUNET_PeerIdentity *) &dvb[1];
- (void) cls;
- if (size < sizeof(*dvb) + num_hops * sizeof(struct GNUNET_PeerIdentity)
- + sizeof(struct GNUNET_MessageHeader))
- {
- GNUNET_break_op (0);
- return GNUNET_SYSERR;
- }
- /* This peer must not be on the path */
- for (unsigned int i = 0; i < num_hops; i++)
- if (0 == GNUNET_memcmp (&hops[i], &GST_my_identity))
- {
- GNUNET_break_op (0);
- return GNUNET_SYSERR;
- }
- return GNUNET_YES;
- }
- /**
- * Create a DV Box message and queue it for transmission to
- * @ea next_hop.
- *
- * @param next_hop peer to receive the message next
- * @param total_hops how many hops did the message take so far
- * @param num_hops length of the @a hops array
- * @param origin origin of the message
- * @param hops next peer(s) to the destination, including destination
- * @param payload payload of the box
- * @param payload_size number of bytes in @a payload
- */
- static void
- forward_dv_box (struct Neighbour *next_hop,
- const struct TransportDVBoxMessage *hdr,
- uint16_t total_hops,
- uint16_t num_hops,
- const struct GNUNET_PeerIdentity *hops,
- const void *enc_payload,
- uint16_t enc_payload_size)
- {
- struct VirtualLink *vl = next_hop->vl;
- struct PendingMessage *pm;
- size_t msg_size;
- char *buf;
- struct GNUNET_PeerIdentity *dhops;
- GNUNET_assert (NULL != vl);
- msg_size = sizeof(struct TransportDVBoxMessage)
- + num_hops * sizeof(struct GNUNET_PeerIdentity) + enc_payload_size;
- pm = GNUNET_malloc (sizeof(struct PendingMessage) + msg_size);
- pm->pmt = PMT_DV_BOX;
- pm->vl = vl;
- pm->timeout = GNUNET_TIME_relative_to_absolute (DV_FORWARD_TIMEOUT);
- pm->logging_uuid = logging_uuid_gen++;
- pm->prefs = GNUNET_MQ_PRIO_BACKGROUND;
- pm->bytes_msg = msg_size;
- buf = (char *) &pm[1];
- memcpy (buf, hdr, sizeof(*hdr));
- dhops =
- (struct GNUNET_PeerIdentity *) &buf[sizeof(struct TransportDVBoxMessage)];
- memcpy (dhops, hops, num_hops * sizeof(struct GNUNET_PeerIdentity));
- memcpy (&dhops[num_hops], enc_payload, enc_payload_size);
- GNUNET_CONTAINER_MDLL_insert (vl,
- vl->pending_msg_head,
- vl->pending_msg_tail,
- pm);
- GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
- "Created pending message %llu for DV Box with next hop %s (%u/%u)\n",
- pm->logging_uuid,
- GNUNET_i2s (&next_hop->pid),
- (unsigned int) num_hops,
- (unsigned int) total_hops);
- check_vl_transmission (vl);
- }
- /**
- * Free data structures associated with @a b.
- *
- * @param b data structure to release
- */
- static void
- free_backtalker (struct Backtalker *b)
- {
- if (NULL != b->get)
- {
- GNUNET_PEERSTORE_iterate_cancel (b->get);
- b->get = NULL;
- GNUNET_assert (NULL != b->cmc);
- finish_cmc_handling (b->cmc);
- b->cmc = NULL;
- }
- if (NULL != b->task)
- {
- GNUNET_SCHEDULER_cancel (b->task);
- b->task = NULL;
- }
- if (NULL != b->sc)
- {
- GNUNET_PEERSTORE_store_cancel (b->sc);
- b->sc = NULL;
- }
- GNUNET_assert (
- GNUNET_YES ==
- GNUNET_CONTAINER_multipeermap_remove (backtalkers, &b->pid, b));
- GNUNET_free (b);
- }
- /**
- * Callback to free backtalker records.
- *
- * @param cls NULL
- * @param pid unused
- * @param value a `struct Backtalker`
- * @return #GNUNET_OK (always)
- */
- static int
- free_backtalker_cb (void *cls,
- const struct GNUNET_PeerIdentity *pid,
- void *value)
- {
- struct Backtalker *b = value;
- (void) cls;
- (void) pid;
- free_backtalker (b);
- return GNUNET_OK;
- }
- /**
- * Function called when it is time to clean up a backtalker.
- *
- * @param cls a `struct Backtalker`
- */
- static void
- backtalker_timeout_cb (void *cls)
- {
- struct Backtalker *b = cls;
- b->task = NULL;
- if (0 != GNUNET_TIME_absolute_get_remaining (b->timeout).rel_value_us)
- {
- b->task = GNUNET_SCHEDULER_add_at (b->timeout, &backtalker_timeout_cb, b);
- return;
- }
- GNUNET_assert (NULL == b->sc);
- free_backtalker (b);
- }
- /**
- * Function called with the monotonic time of a backtalker
- * by PEERSTORE. Updates the time and continues processing.
- *
- * @param cls a `struct Backtalker`
- * @param record the information found, NULL for the last call
- * @param emsg error message
- */
- static void
- backtalker_monotime_cb (void *cls,
- const struct GNUNET_PEERSTORE_Record *record,
- const char *emsg)
- {
- struct Backtalker *b = cls;
- struct GNUNET_TIME_AbsoluteNBO *mtbe;
- struct GNUNET_TIME_Absolute mt;
- (void) emsg;
- if (NULL == record)
- {
- /* we're done with #backtalker_monotime_cb() invocations,
- continue normal processing */
- b->get = NULL;
- GNUNET_assert (NULL != b->cmc);
- if (0 != b->body_size)
- demultiplex_with_cmc (b->cmc,
- (const struct GNUNET_MessageHeader *) &b[1]);
- else
- finish_cmc_handling (b->cmc);
- b->cmc = NULL;
- return;
- }
- if (sizeof(*mtbe) != record->value_size)
- {
- GNUNET_break (0);
- return;
- }
- mtbe = record->value;
- mt = GNUNET_TIME_absolute_ntoh (*mtbe);
- if (mt.abs_value_us > b->monotonic_time.abs_value_us)
- {
- GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
- "Backtalker message from %s dropped, monotime in the past\n",
- GNUNET_i2s (&b->pid));
- GNUNET_STATISTICS_update (
- GST_stats,
- "# Backchannel messages dropped: monotonic time not increasing",
- 1,
- GNUNET_NO);
- b->monotonic_time = mt;
- /* Setting body_size to 0 prevents call to #forward_backchannel_payload()
- */
- b->body_size = 0;
- return;
- }
- }
- /**
- * Function called by PEERSTORE when the store operation of
- * a backtalker's monotonic time is complete.
- *
- * @param cls the `struct Backtalker`
- * @param success #GNUNET_OK on success
- */
- static void
- backtalker_monotime_store_cb (void *cls, int success)
- {
- struct Backtalker *b = cls;
- if (GNUNET_OK != success)
- {
- GNUNET_log (GNUNET_ERROR_TYPE_ERROR,
- "Failed to store backtalker's monotonic time in PEERSTORE!\n");
- }
- b->sc = NULL;
- b->task = GNUNET_SCHEDULER_add_at (b->timeout, &backtalker_timeout_cb, b);
- }
- /**
- * The backtalker @a b monotonic time changed. Update PEERSTORE.
- *
- * @param b a backtalker with updated monotonic time
- */
- static void
- update_backtalker_monotime (struct Backtalker *b)
- {
- struct GNUNET_TIME_AbsoluteNBO mtbe;
- if (NULL != b->sc)
- {
- GNUNET_PEERSTORE_store_cancel (b->sc);
- b->sc = NULL;
- }
- else
- {
- GNUNET_SCHEDULER_cancel (b->task);
- b->task = NULL;
- }
- mtbe = GNUNET_TIME_absolute_hton (b->monotonic_time);
- b->sc =
- GNUNET_PEERSTORE_store (peerstore,
- "transport",
- &b->pid,
- GNUNET_PEERSTORE_TRANSPORT_BACKCHANNEL_MONOTIME,
- &mtbe,
- sizeof(mtbe),
- GNUNET_TIME_UNIT_FOREVER_ABS,
- GNUNET_PEERSTORE_STOREOPTION_REPLACE,
- &backtalker_monotime_store_cb,
- b);
- }
- /**
- * Communicator gave us a DV box. Process the request.
- *
- * @param cls a `struct CommunicatorMessageContext` (must call
- * #finish_cmc_handling() when done)
- * @param dvb the message that was received
- */
- static void
- handle_dv_box (void *cls, const struct TransportDVBoxMessage *dvb)
- {
- struct CommunicatorMessageContext *cmc = cls;
- uint16_t size = ntohs (dvb->header.size) - sizeof(*dvb);
- uint16_t num_hops = ntohs (dvb->num_hops);
- const struct GNUNET_PeerIdentity *hops =
- (const struct GNUNET_PeerIdentity *) &dvb[1];
- const char *enc_payload = (const char *) &hops[num_hops];
- uint16_t enc_payload_size =
- size - (num_hops * sizeof(struct GNUNET_PeerIdentity));
- struct DVKeyState key;
- struct GNUNET_HashCode hmac;
- const char *hdr;
- size_t hdr_len;
- if (GNUNET_EXTRA_LOGGING > 0)
- {
- char *path;
- path = GNUNET_strdup (GNUNET_i2s (&GST_my_identity));
- for (unsigned int i = 0; i < num_hops; i++)
- {
- char *tmp;
- GNUNET_asprintf (&tmp, "%s->%s", path, GNUNET_i2s (&hops[i]));
- GNUNET_free (path);
- path = tmp;
- }
- GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
- "Received DVBox with remainig path %s\n",
- path);
- GNUNET_free (path);
- }
- if (num_hops > 0)
- {
- /* We're trying from the end of the hops array, as we may be
- able to find a shortcut unknown to the origin that way */
- for (int i = num_hops - 1; i >= 0; i--)
- {
- struct Neighbour *n;
- if (0 == GNUNET_memcmp (&hops[i], &GST_my_identity))
- {
- GNUNET_break_op (0);
- finish_cmc_handling (cmc);
- return;
- }
- n = lookup_neighbour (&hops[i]);
- if (NULL == n)
- continue;
- GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
- "Skipping %u/%u hops ahead while routing DV Box\n",
- i,
- num_hops);
- forward_dv_box (n,
- dvb,
- ntohs (dvb->total_hops) + 1,
- num_hops - i - 1, /* number of hops left */
- &hops[i + 1], /* remaining hops */
- enc_payload,
- enc_payload_size);
- GNUNET_STATISTICS_update (GST_stats,
- "# DV hops skipped routing boxes",
- i,
- GNUNET_NO);
- GNUNET_STATISTICS_update (GST_stats,
- "# DV boxes routed (total)",
- 1,
- GNUNET_NO);
- finish_cmc_handling (cmc);
- return;
- }
- /* Woopsie, next hop not in neighbours, drop! */
- GNUNET_STATISTICS_update (GST_stats,
- "# DV Boxes dropped: next hop unknown",
- 1,
- GNUNET_NO);
- finish_cmc_handling (cmc);
- return;
- }
- /* We are the target. Unbox and handle message. */
- GNUNET_STATISTICS_update (GST_stats,
- "# DV boxes opened (ultimate target)",
- 1,
- GNUNET_NO);
- cmc->total_hops = ntohs (dvb->total_hops);
- dh_key_derive_eph_pub (&dvb->ephemeral_key, &dvb->iv, &key);
- hdr = (const char *) &dvb[1];
- hdr_len = ntohs (dvb->header.size) - sizeof(*dvb);
- dv_hmac (&key, &hmac, hdr, hdr_len);
- if (0 != GNUNET_memcmp (&hmac, &dvb->hmac))
- {
- /* HMAC missmatch, disard! */
- GNUNET_break_op (0);
- finish_cmc_handling (cmc);
- return;
- }
- /* begin actual decryption */
- {
- struct Backtalker *b;
- struct GNUNET_TIME_Absolute monotime;
- struct TransportDVBoxPayloadP ppay;
- char body[hdr_len - sizeof(ppay)] GNUNET_ALIGN;
- const struct GNUNET_MessageHeader *mh =
- (const struct GNUNET_MessageHeader *) body;
- GNUNET_assert (hdr_len >=
- sizeof(ppay) + sizeof(struct GNUNET_MessageHeader));
- dv_decrypt (&key, &ppay, hdr, sizeof(ppay));
- dv_decrypt (&key, &body, &hdr[sizeof(ppay)], hdr_len - sizeof(ppay));
- dv_key_clean (&key);
- if (ntohs (mh->size) != sizeof(body))
- {
- GNUNET_break_op (0);
- finish_cmc_handling (cmc);
- return;
- }
- /* need to prevent box-in-a-box (and DV_LEARN) so check inbox type! */
- switch (ntohs (mh->type))
- {
- case GNUNET_MESSAGE_TYPE_TRANSPORT_DV_BOX:
- GNUNET_break_op (0);
- finish_cmc_handling (cmc);
- return;
- case GNUNET_MESSAGE_TYPE_TRANSPORT_DV_LEARN:
- GNUNET_break_op (0);
- finish_cmc_handling (cmc);
- return;
- default:
- /* permitted, continue */
- break;
- }
- monotime = GNUNET_TIME_absolute_ntoh (ppay.monotonic_time);
- GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
- "Decrypted backtalk from %s\n",
- GNUNET_i2s (&ppay.sender));
- b = GNUNET_CONTAINER_multipeermap_get (backtalkers, &ppay.sender);
- if ((NULL != b) && (monotime.abs_value_us < b->monotonic_time.abs_value_us))
- {
- GNUNET_STATISTICS_update (
- GST_stats,
- "# Backchannel messages dropped: monotonic time not increasing",
- 1,
- GNUNET_NO);
- finish_cmc_handling (cmc);
- return;
- }
- if ((NULL == b) ||
- (0 != GNUNET_memcmp (&b->last_ephemeral, &dvb->ephemeral_key)))
- {
- /* Check signature */
- struct EphemeralConfirmationPS ec;
- ec.purpose.purpose = htonl (GNUNET_SIGNATURE_PURPOSE_TRANSPORT_EPHEMERAL);
- ec.purpose.size = htonl (sizeof(ec));
- ec.target = GST_my_identity;
- ec.ephemeral_key = dvb->ephemeral_key;
- if (
- GNUNET_OK !=
- GNUNET_CRYPTO_eddsa_verify (
- GNUNET_SIGNATURE_PURPOSE_TRANSPORT_EPHEMERAL,
- &ec,
- &ppay.sender_sig,
- &ppay.sender.public_key))
- {
- /* Signature invalid, disard! */
- GNUNET_break_op (0);
- finish_cmc_handling (cmc);
- return;
- }
- }
- /* Update sender, we now know the real origin! */
- GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
- "DVBox received for me from %s via %s\n",
- GNUNET_i2s2 (&ppay.sender),
- GNUNET_i2s (&cmc->im.sender));
- cmc->im.sender = ppay.sender;
- if (NULL != b)
- {
- /* update key cache and mono time */
- b->last_ephemeral = dvb->ephemeral_key;
- b->monotonic_time = monotime;
- update_backtalker_monotime (b);
- b->timeout =
- GNUNET_TIME_relative_to_absolute (BACKCHANNEL_INACTIVITY_TIMEOUT);
- demultiplex_with_cmc (cmc, mh);
- return;
- }
- /* setup data structure to cache signature AND check
- monotonic time with PEERSTORE before forwarding backchannel payload */
- b = GNUNET_malloc (sizeof(struct Backtalker) + sizeof(body));
- b->pid = ppay.sender;
- b->body_size = sizeof(body);
- memcpy (&b[1], body, sizeof(body));
- GNUNET_assert (GNUNET_YES ==
- GNUNET_CONTAINER_multipeermap_put (
- backtalkers,
- &b->pid,
- b,
- GNUNET_CONTAINER_MULTIHASHMAPOPTION_UNIQUE_ONLY));
- b->monotonic_time = monotime; /* NOTE: to be checked still! */
- b->cmc = cmc;
- b->timeout =
- GNUNET_TIME_relative_to_absolute (BACKCHANNEL_INACTIVITY_TIMEOUT);
- b->task = GNUNET_SCHEDULER_add_at (b->timeout, &backtalker_timeout_cb, b);
- b->get =
- GNUNET_PEERSTORE_iterate (peerstore,
- "transport",
- &b->pid,
- GNUNET_PEERSTORE_TRANSPORT_BACKCHANNEL_MONOTIME,
- &backtalker_monotime_cb,
- b);
- } /* end actual decryption */
- }
- /**
- * Client notified us about transmission from a peer. Process the request.
- *
- * @param cls a `struct TransportClient` which sent us the message
- * @param obm the send message that was sent
- * @return #GNUNET_YES if message is well-formed
- */
- static int
- check_incoming_msg (void *cls,
- const struct GNUNET_TRANSPORT_IncomingMessage *im)
- {
- struct TransportClient *tc = cls;
- if (CT_COMMUNICATOR != tc->type)
- {
- GNUNET_break (0);
- return GNUNET_SYSERR;
- }
- GNUNET_MQ_check_boxed_message (im);
- return GNUNET_OK;
- }
- /**
- * Closure for #check_known_address.
- */
- struct CheckKnownAddressContext
- {
- /**
- * Set to the address we are looking for.
- */
- const char *address;
- /**
- * Set to a matching validation state, if one was found.
- */
- struct ValidationState *vs;
- };
- /**
- * Test if the validation state in @a value matches the
- * address from @a cls.
- *
- * @param cls a `struct CheckKnownAddressContext`
- * @param pid unused (must match though)
- * @param value a `struct ValidationState`
- * @return #GNUNET_OK if not matching, #GNUNET_NO if match found
- */
- static int
- check_known_address (void *cls,
- const struct GNUNET_PeerIdentity *pid,
- void *value)
- {
- struct CheckKnownAddressContext *ckac = cls;
- struct ValidationState *vs = value;
- (void) pid;
- if (0 != strcmp (vs->address, ckac->address))
- return GNUNET_OK;
- ckac->vs = vs;
- return GNUNET_NO;
- }
- /**
- * Task run periodically to validate some address based on #validation_heap.
- *
- * @param cls NULL
- */
- static void
- validation_start_cb (void *cls);
- /**
- * Set the time for next_challenge of @a vs to @a new_time.
- * Updates the heap and if necessary reschedules the job.
- *
- * @param vs validation state to update
- * @param new_time new time for revalidation
- */
- static void
- update_next_challenge_time (struct ValidationState *vs,
- struct GNUNET_TIME_Absolute new_time)
- {
- struct GNUNET_TIME_Relative delta;
- if (new_time.abs_value_us == vs->next_challenge.abs_value_us)
- return; /* be lazy */
- vs->next_challenge = new_time;
- if (NULL == vs->hn)
- vs->hn =
- GNUNET_CONTAINER_heap_insert (validation_heap, vs, new_time.abs_value_us);
- else
- GNUNET_CONTAINER_heap_update_cost (vs->hn, new_time.abs_value_us);
- if ((vs != GNUNET_CONTAINER_heap_peek (validation_heap)) &&
- (NULL != validation_task))
- return;
- if (NULL != validation_task)
- GNUNET_SCHEDULER_cancel (validation_task);
- /* randomize a bit */
- delta.rel_value_us =
- GNUNET_CRYPTO_random_u64 (GNUNET_CRYPTO_QUALITY_WEAK,
- MIN_DELAY_ADDRESS_VALIDATION.rel_value_us);
- new_time = GNUNET_TIME_absolute_add (new_time, delta);
- validation_task =
- GNUNET_SCHEDULER_add_at (new_time, &validation_start_cb, NULL);
- }
- /**
- * Start address validation.
- *
- * @param pid peer the @a address is for
- * @param address an address to reach @a pid (presumably)
- */
- static void
- start_address_validation (const struct GNUNET_PeerIdentity *pid,
- const char *address)
- {
- struct GNUNET_TIME_Absolute now;
- struct ValidationState *vs;
- struct CheckKnownAddressContext ckac = { .address = address, .vs = NULL };
- (void) GNUNET_CONTAINER_multipeermap_get_multiple (validation_map,
- pid,
- &check_known_address,
- &ckac);
- if (NULL != (vs = ckac.vs))
- {
- /* if 'vs' is not currently valid, we need to speed up retrying the
- * validation */
- if (vs->validated_until.abs_value_us < vs->next_challenge.abs_value_us)
- {
- /* reduce backoff as we got a fresh advertisement */
- vs->challenge_backoff =
- GNUNET_TIME_relative_min (FAST_VALIDATION_CHALLENGE_FREQ,
- GNUNET_TIME_relative_divide (
- vs->challenge_backoff,
- 2));
- update_next_challenge_time (vs,
- GNUNET_TIME_relative_to_absolute (
- vs->challenge_backoff));
- }
- return;
- }
- now = GNUNET_TIME_absolute_get ();
- vs = GNUNET_new (struct ValidationState);
- vs->pid = *pid;
- vs->valid_until =
- GNUNET_TIME_relative_to_absolute (ADDRESS_VALIDATION_LIFETIME);
- vs->first_challenge_use = now;
- vs->validation_rtt = GNUNET_TIME_UNIT_FOREVER_REL;
- GNUNET_CRYPTO_random_block (GNUNET_CRYPTO_QUALITY_NONCE,
- &vs->challenge,
- sizeof(vs->challenge));
- vs->address = GNUNET_strdup (address);
- GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
- "Starting address validation `%s' of peer %s using challenge %s\n",
- address,
- GNUNET_i2s (pid),
- GNUNET_sh2s (&vs->challenge.value));
- GNUNET_assert (GNUNET_YES ==
- GNUNET_CONTAINER_multipeermap_put (
- validation_map,
- &vs->pid,
- vs,
- GNUNET_CONTAINER_MULTIHASHMAPOPTION_UNIQUE_ONLY));
- update_next_challenge_time (vs, now);
- }
- /**
- * Function called by PEERSTORE for each matching record.
- *
- * @param cls closure, a `struct IncomingRequest`
- * @param record peerstore record information
- * @param emsg error message, or NULL if no errors
- */
- static void
- handle_hello_for_incoming (void *cls,
- const struct GNUNET_PEERSTORE_Record *record,
- const char *emsg)
- {
- struct IncomingRequest *ir = cls;
- const char *val;
- if (NULL != emsg)
- {
- GNUNET_log (GNUNET_ERROR_TYPE_WARNING,
- "Got failure from PEERSTORE: %s\n",
- emsg);
- return;
- }
- val = record->value;
- if ((0 == record->value_size) || ('\0' != val[record->value_size - 1]))
- {
- GNUNET_break (0);
- return;
- }
- start_address_validation (&ir->pid, (const char *) record->value);
- }
- /**
- * Communicator gave us a transport address validation challenge. Process the
- * request.
- *
- * @param cls a `struct CommunicatorMessageContext` (must call
- * #finish_cmc_handling() when done)
- * @param tvc the message that was received
- */
- static void
- handle_validation_challenge (
- void *cls,
- const struct TransportValidationChallengeMessage *tvc)
- {
- struct CommunicatorMessageContext *cmc = cls;
- struct TransportValidationResponseMessage tvr;
- struct VirtualLink *vl;
- struct GNUNET_TIME_RelativeNBO validity_duration;
- struct IncomingRequest *ir;
- struct Neighbour *n;
- struct GNUNET_PeerIdentity sender;
- /* DV-routed messages are not allowed for validation challenges */
- if (cmc->total_hops > 0)
- {
- GNUNET_break_op (0);
- finish_cmc_handling (cmc);
- return;
- }
- validity_duration = cmc->im.expected_address_validity;
- GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
- "Received address validation challenge %s\n",
- GNUNET_sh2s (&tvc->challenge.value));
- /* If we have a virtual link, we use this mechanism to signal the
- size of the flow control window, and to allow the sender
- to ask for increases. If for us the virtual link is still down,
- we will always give a window size of zero. */
- tvr.header.type =
- htons (GNUNET_MESSAGE_TYPE_TRANSPORT_ADDRESS_VALIDATION_RESPONSE);
- tvr.header.size = htons (sizeof(tvr));
- tvr.reserved = htonl (0);
- tvr.challenge = tvc->challenge;
- tvr.origin_time = tvc->sender_time;
- tvr.validity_duration = validity_duration;
- {
- /* create signature */
- struct TransportValidationPS tvp = {
- .purpose.purpose = htonl (GNUNET_SIGNATURE_PURPOSE_TRANSPORT_CHALLENGE),
- .purpose.size = htonl (sizeof(tvp)),
- .validity_duration = validity_duration,
- .challenge = tvc->challenge
- };
- GNUNET_CRYPTO_eddsa_sign (GST_my_private_key,
- &tvp,
- &tvr.signature);
- }
- route_control_message_without_fc (&cmc->im.sender,
- &tvr.header,
- RMO_ANYTHING_GOES | RMO_REDUNDANT);
- sender = cmc->im.sender;
- finish_cmc_handling (cmc);
- vl = lookup_virtual_link (&sender);
- if (NULL != vl)
- return;
- /* For us, the link is still down, but we need bi-directional
- connections (for flow-control and for this to be useful for
- CORE), so we must try to bring the link up! */
- /* (1) Check existing queues, if any, we may be lucky! */
- n = lookup_neighbour (&sender);
- if (NULL != n)
- for (struct Queue *q = n->queue_head; NULL != q; q = q->next_neighbour)
- start_address_validation (&sender, q->address);
- /* (2) Also try to see if we have addresses in PEERSTORE for this peer
- we could use */
- for (ir = ir_head; NULL != ir; ir = ir->next)
- if (0 == GNUNET_memcmp (&ir->pid, &sender))
- return;
- /* we are already trying */
- ir = GNUNET_new (struct IncomingRequest);
- ir->pid = sender;
- GNUNET_CONTAINER_DLL_insert (ir_head, ir_tail, ir);
- ir->wc = GNUNET_PEERSTORE_watch (peerstore,
- "transport",
- &ir->pid,
- GNUNET_PEERSTORE_TRANSPORT_URLADDRESS_KEY,
- &handle_hello_for_incoming,
- ir);
- ir_total++;
- /* Bound attempts we do in parallel here, might otherwise get excessive */
- while (ir_total > MAX_INCOMING_REQUEST)
- free_incoming_request (ir_head);
- }
- /**
- * Closure for #check_known_challenge.
- */
- struct CheckKnownChallengeContext
- {
- /**
- * Set to the challenge we are looking for.
- */
- const struct ChallengeNonceP *challenge;
- /**
- * Set to a matching validation state, if one was found.
- */
- struct ValidationState *vs;
- };
- /**
- * Test if the validation state in @a value matches the
- * challenge from @a cls.
- *
- * @param cls a `struct CheckKnownChallengeContext`
- * @param pid unused (must match though)
- * @param value a `struct ValidationState`
- * @return #GNUNET_OK if not matching, #GNUNET_NO if match found
- */
- static int
- check_known_challenge (void *cls,
- const struct GNUNET_PeerIdentity *pid,
- void *value)
- {
- struct CheckKnownChallengeContext *ckac = cls;
- struct ValidationState *vs = value;
- (void) pid;
- if (0 != GNUNET_memcmp (&vs->challenge, ckac->challenge))
- return GNUNET_OK;
- ckac->vs = vs;
- return GNUNET_NO;
- }
- /**
- * Function called when peerstore is done storing a
- * validated address.
- *
- * @param cls a `struct ValidationState`
- * @param success #GNUNET_YES on success
- */
- static void
- peerstore_store_validation_cb (void *cls, int success)
- {
- struct ValidationState *vs = cls;
- vs->sc = NULL;
- if (GNUNET_YES == success)
- return;
- GNUNET_STATISTICS_update (GST_stats,
- "# Peerstore failed to store foreign address",
- 1,
- GNUNET_NO);
- }
- /**
- * Find the queue matching @a pid and @a address.
- *
- * @param pid peer the queue must go to
- * @param address address the queue must use
- * @return NULL if no such queue exists
- */
- static struct Queue *
- find_queue (const struct GNUNET_PeerIdentity *pid, const char *address)
- {
- struct Neighbour *n;
- n = lookup_neighbour (pid);
- if (NULL == n)
- return NULL;
- for (struct Queue *pos = n->queue_head; NULL != pos;
- pos = pos->next_neighbour)
- {
- if (0 == strcmp (pos->address, address))
- return pos;
- }
- return NULL;
- }
- /**
- * Communicator gave us a transport address validation response. Process the
- * request.
- *
- * @param cls a `struct CommunicatorMessageContext` (must call
- * #finish_cmc_handling() when done)
- * @param tvr the message that was received
- */
- static void
- handle_validation_response (
- void *cls,
- const struct TransportValidationResponseMessage *tvr)
- {
- struct CommunicatorMessageContext *cmc = cls;
- struct ValidationState *vs;
- struct CheckKnownChallengeContext ckac = { .challenge = &tvr->challenge,
- .vs = NULL };
- struct GNUNET_TIME_Absolute origin_time;
- struct Queue *q;
- struct Neighbour *n;
- struct VirtualLink *vl;
- /* check this is one of our challenges */
- (void) GNUNET_CONTAINER_multipeermap_get_multiple (validation_map,
- &cmc->im.sender,
- &check_known_challenge,
- &ckac);
- if (NULL == (vs = ckac.vs))
- {
- /* This can happen simply if we 'forgot' the challenge by now,
- i.e. because we received the validation response twice */
- GNUNET_STATISTICS_update (GST_stats,
- "# Validations dropped, challenge unknown",
- 1,
- GNUNET_NO);
- GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
- "Validation response %s dropped, challenge unknown\n",
- GNUNET_sh2s (&tvr->challenge.value));
- finish_cmc_handling (cmc);
- return;
- }
- /* sanity check on origin time */
- origin_time = GNUNET_TIME_absolute_ntoh (tvr->origin_time);
- if ((origin_time.abs_value_us < vs->first_challenge_use.abs_value_us) ||
- (origin_time.abs_value_us > vs->last_challenge_use.abs_value_us))
- {
- GNUNET_break_op (0);
- finish_cmc_handling (cmc);
- return;
- }
- {
- /* check signature */
- struct TransportValidationPS tvp = {
- .purpose.purpose = htonl (GNUNET_SIGNATURE_PURPOSE_TRANSPORT_CHALLENGE),
- .purpose.size = htonl (sizeof(tvp)),
- .validity_duration = tvr->validity_duration,
- .challenge = tvr->challenge
- };
- if (
- GNUNET_OK !=
- GNUNET_CRYPTO_eddsa_verify (GNUNET_SIGNATURE_PURPOSE_TRANSPORT_CHALLENGE,
- &tvp,
- &tvr->signature,
- &cmc->im.sender.public_key))
- {
- GNUNET_break_op (0);
- finish_cmc_handling (cmc);
- return;
- }
- }
- /* validity is capped by our willingness to keep track of the
- validation entry and the maximum the other peer allows */
- vs->valid_until = GNUNET_TIME_relative_to_absolute (
- GNUNET_TIME_relative_min (GNUNET_TIME_relative_ntoh (
- tvr->validity_duration),
- MAX_ADDRESS_VALID_UNTIL));
- vs->validated_until =
- GNUNET_TIME_absolute_min (vs->valid_until,
- GNUNET_TIME_relative_to_absolute (
- ADDRESS_VALIDATION_LIFETIME));
- vs->validation_rtt = GNUNET_TIME_absolute_get_duration (origin_time);
- vs->challenge_backoff = GNUNET_TIME_UNIT_ZERO;
- GNUNET_CRYPTO_random_block (GNUNET_CRYPTO_QUALITY_NONCE,
- &vs->challenge,
- sizeof(vs->challenge));
- vs->first_challenge_use = GNUNET_TIME_absolute_subtract (
- vs->validated_until,
- GNUNET_TIME_relative_multiply (vs->validation_rtt,
- VALIDATION_RTT_BUFFER_FACTOR));
- vs->last_challenge_use =
- GNUNET_TIME_UNIT_ZERO_ABS; /* challenge was not yet used */
- update_next_challenge_time (vs, vs->first_challenge_use);
- GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
- "Validation response %s accepted, address valid until %s\n",
- GNUNET_sh2s (&tvr->challenge.value),
- GNUNET_STRINGS_absolute_time_to_string (vs->valid_until));
- vs->sc = GNUNET_PEERSTORE_store (peerstore,
- "transport",
- &cmc->im.sender,
- GNUNET_PEERSTORE_TRANSPORT_URLADDRESS_KEY,
- vs->address,
- strlen (vs->address) + 1,
- vs->valid_until,
- GNUNET_PEERSTORE_STOREOPTION_MULTIPLE,
- &peerstore_store_validation_cb,
- vs);
- finish_cmc_handling (cmc);
- /* Finally, we now possibly have a confirmed (!) working queue,
- update queue status (if queue still is around) */
- q = find_queue (&vs->pid, vs->address);
- if (NULL == q)
- {
- GNUNET_STATISTICS_update (GST_stats,
- "# Queues lost at time of successful validation",
- 1,
- GNUNET_NO);
- return;
- }
- q->validated_until = vs->validated_until;
- q->pd.aged_rtt = vs->validation_rtt;
- n = q->neighbour;
- vl = lookup_virtual_link (&vs->pid);
- if (NULL != vl)
- {
- /* Link was already up, remember n is also now available and we are done */
- if (NULL == vl->n)
- {
- vl->n = n;
- n->vl = vl;
- GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
- "Virtual link to %s could now also direct neighbour!\n",
- GNUNET_i2s (&vs->pid));
- }
- else
- {
- GNUNET_assert (n == vl->n);
- }
- return;
- }
- GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
- "Creating new virtual link to %s using direct neighbour!\n",
- GNUNET_i2s (&vs->pid));
- vl = GNUNET_new (struct VirtualLink);
- vl->target = n->pid;
- vl->n = n;
- n->vl = vl;
- vl->core_recv_window = RECV_WINDOW_SIZE;
- vl->available_fc_window_size = DEFAULT_WINDOW_SIZE;
- vl->visibility_task =
- GNUNET_SCHEDULER_add_at (q->validated_until, &check_link_down, vl);
- GNUNET_break (GNUNET_YES ==
- GNUNET_CONTAINER_multipeermap_put (
- links,
- &vl->target,
- vl,
- GNUNET_CONTAINER_MULTIHASHMAPOPTION_UNIQUE_ONLY));
- consider_sending_fc (vl);
- /* We lacked a confirmed connection to the target
- before, so tell CORE about it (finally!) */
- cores_send_connect_info (&n->pid);
- }
- /**
- * Incoming meessage. Process the request.
- *
- * @param im the send message that was received
- */
- static void
- handle_incoming_msg (void *cls,
- const struct GNUNET_TRANSPORT_IncomingMessage *im)
- {
- struct TransportClient *tc = cls;
- struct CommunicatorMessageContext *cmc =
- GNUNET_new (struct CommunicatorMessageContext);
- cmc->tc = tc;
- cmc->im = *im;
- GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
- "Received message via communicator from peer %s\n",
- GNUNET_i2s (&im->sender));
- demultiplex_with_cmc (cmc, (const struct GNUNET_MessageHeader *) &im[1]);
- }
- /**
- * Communicator gave us a transport address validation response. Process the
- * request.
- *
- * @param cls a `struct CommunicatorMessageContext` (must call
- * #finish_cmc_handling() when done)
- * @param fc the message that was received
- */
- static void
- handle_flow_control (void *cls, const struct TransportFlowControlMessage *fc)
- {
- struct CommunicatorMessageContext *cmc = cls;
- struct VirtualLink *vl;
- uint32_t seq;
- struct GNUNET_TIME_Absolute st;
- uint64_t os;
- uint64_t wnd;
- vl = lookup_virtual_link (&cmc->im.sender);
- if (NULL == vl)
- {
- GNUNET_STATISTICS_update (GST_stats,
- "# FC dropped: virtual link unknown",
- 1,
- GNUNET_NO);
- finish_cmc_handling (cmc);
- return;
- }
- st = GNUNET_TIME_absolute_ntoh (fc->sender_time);
- if (st.abs_value_us < vl->last_fc_timestamp.abs_value_us)
- {
- /* out of order, drop */
- GNUNET_STATISTICS_update (GST_stats,
- "# FC dropped: message out of order",
- 1,
- GNUNET_NO);
- finish_cmc_handling (cmc);
- return;
- }
- seq = ntohl (fc->seq);
- if (seq < vl->last_fc_seq)
- {
- /* Wrap-around/reset of other peer; start all counters from zero */
- vl->outbound_fc_window_size_used = 0;
- }
- vl->last_fc_seq = seq;
- vl->last_fc_timestamp = st;
- vl->outbound_fc_window_size = GNUNET_ntohll (fc->inbound_window_size);
- os = GNUNET_ntohll (fc->outbound_sent);
- vl->incoming_fc_window_size_loss =
- (int64_t) (os - vl->incoming_fc_window_size_used);
- GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
- "Received FC from %s, seq %u, new window %llu (loss at %lld)\n",
- GNUNET_i2s (&vl->target),
- (unsigned int) seq,
- (unsigned long long) vl->outbound_fc_window_size,
- (long long) vl->incoming_fc_window_size_loss);
- wnd = GNUNET_ntohll (fc->outbound_window_size);
- if ((wnd < vl->incoming_fc_window_size) ||
- (vl->last_outbound_window_size_received != wnd) ||
- (0 == GNUNET_CRYPTO_random_u32 (GNUNET_CRYPTO_QUALITY_WEAK, UINT32_MAX)
- % FC_NO_CHANGE_REPLY_PROBABILITY))
- {
- /* Consider re-sending our FC message, as clearly the
- other peer's idea of the window is not up-to-date */
- consider_sending_fc (vl);
- }
- if ((wnd == vl->incoming_fc_window_size) &&
- (vl->last_outbound_window_size_received == wnd) &&
- (NULL != vl->fc_retransmit_task))
- {
- GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
- "Stopping FC retransmission to %s: peer is current at window %llu\n",
- GNUNET_i2s (&vl->target),
- (unsigned long long) wnd);
- GNUNET_SCHEDULER_cancel (vl->fc_retransmit_task);
- vl->fc_retransmit_task = NULL;
- }
- vl->last_outbound_window_size_received = wnd;
- /* FC window likely increased, check transmission possibilities! */
- check_vl_transmission (vl);
- finish_cmc_handling (cmc);
- }
- /**
- * Given an inbound message @a msg from a communicator @a cmc,
- * demultiplex it based on the type calling the right handler.
- *
- * @param cmc context for demultiplexing
- * @param msg message to demultiplex
- */
- static void
- demultiplex_with_cmc (struct CommunicatorMessageContext *cmc,
- const struct GNUNET_MessageHeader *msg)
- {
- struct GNUNET_MQ_MessageHandler handlers[] =
- { GNUNET_MQ_hd_var_size (fragment_box,
- GNUNET_MESSAGE_TYPE_TRANSPORT_FRAGMENT,
- struct TransportFragmentBoxMessage,
- &cmc),
- GNUNET_MQ_hd_var_size (reliability_box,
- GNUNET_MESSAGE_TYPE_TRANSPORT_RELIABILITY_BOX,
- struct TransportReliabilityBoxMessage,
- &cmc),
- GNUNET_MQ_hd_var_size (reliability_ack,
- GNUNET_MESSAGE_TYPE_TRANSPORT_RELIABILITY_ACK,
- struct TransportReliabilityAckMessage,
- &cmc),
- GNUNET_MQ_hd_var_size (backchannel_encapsulation,
- GNUNET_MESSAGE_TYPE_TRANSPORT_BACKCHANNEL_ENCAPSULATION,
- struct TransportBackchannelEncapsulationMessage,
- &cmc),
- GNUNET_MQ_hd_var_size (dv_learn,
- GNUNET_MESSAGE_TYPE_TRANSPORT_DV_LEARN,
- struct TransportDVLearnMessage,
- &cmc),
- GNUNET_MQ_hd_var_size (dv_box,
- GNUNET_MESSAGE_TYPE_TRANSPORT_DV_BOX,
- struct TransportDVBoxMessage,
- &cmc),
- GNUNET_MQ_hd_fixed_size (
- validation_challenge,
- GNUNET_MESSAGE_TYPE_TRANSPORT_ADDRESS_VALIDATION_CHALLENGE,
- struct TransportValidationChallengeMessage,
- &cmc),
- GNUNET_MQ_hd_fixed_size (flow_control,
- GNUNET_MESSAGE_TYPE_TRANSPORT_FLOW_CONTROL,
- struct TransportFlowControlMessage,
- &cmc),
- GNUNET_MQ_hd_fixed_size (
- validation_response,
- GNUNET_MESSAGE_TYPE_TRANSPORT_ADDRESS_VALIDATION_RESPONSE,
- struct TransportValidationResponseMessage,
- &cmc),
- GNUNET_MQ_handler_end () };
- int ret;
- GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
- "Handling message of type %u with %u bytes\n",
- (unsigned int) ntohs (msg->type),
- (unsigned int) ntohs (msg->size));
- ret = GNUNET_MQ_handle_message (handlers, msg);
- if (GNUNET_SYSERR == ret)
- {
- GNUNET_break (0);
- GNUNET_SERVICE_client_drop (cmc->tc->client);
- GNUNET_free (cmc);
- return;
- }
- if (GNUNET_NO == ret)
- {
- /* unencapsulated 'raw' message */
- handle_raw_message (&cmc, msg);
- }
- }
- /**
- * New queue became available. Check message.
- *
- * @param cls the client
- * @param aqm the send message that was sent
- */
- static int
- check_add_queue_message (void *cls,
- const struct GNUNET_TRANSPORT_AddQueueMessage *aqm)
- {
- struct TransportClient *tc = cls;
- if (CT_COMMUNICATOR != tc->type)
- {
- GNUNET_break (0);
- return GNUNET_SYSERR;
- }
- GNUNET_MQ_check_zero_termination (aqm);
- return GNUNET_OK;
- }
- /**
- * If necessary, generates the UUID for a @a pm
- *
- * @param pm pending message to generate UUID for.
- */
- static void
- set_pending_message_uuid (struct PendingMessage *pm)
- {
- if (pm->msg_uuid_set)
- return;
- pm->msg_uuid.uuid = pm->vl->message_uuid_ctr++;
- pm->msg_uuid_set = GNUNET_YES;
- }
- /**
- * Setup data structure waiting for acknowledgements.
- *
- * @param queue queue the @a pm will be sent over
- * @param dvh path the message will take, may be NULL
- * @param pm the pending message for transmission
- * @return corresponding fresh pending acknowledgement
- */
- static struct PendingAcknowledgement *
- prepare_pending_acknowledgement (struct Queue *queue,
- struct DistanceVectorHop *dvh,
- struct PendingMessage *pm)
- {
- struct PendingAcknowledgement *pa;
- pa = GNUNET_new (struct PendingAcknowledgement);
- pa->queue = queue;
- pa->dvh = dvh;
- pa->pm = pm;
- do
- {
- GNUNET_CRYPTO_random_block (GNUNET_CRYPTO_QUALITY_NONCE,
- &pa->ack_uuid,
- sizeof(pa->ack_uuid));
- }
- while (GNUNET_YES != GNUNET_CONTAINER_multiuuidmap_put (
- pending_acks,
- &pa->ack_uuid.value,
- pa,
- GNUNET_CONTAINER_MULTIHASHMAPOPTION_UNIQUE_ONLY));
- GNUNET_CONTAINER_MDLL_insert (queue, queue->pa_head, queue->pa_tail, pa);
- GNUNET_CONTAINER_MDLL_insert (pm, pm->pa_head, pm->pa_tail, pa);
- if (NULL != dvh)
- GNUNET_CONTAINER_MDLL_insert (dvh, dvh->pa_head, dvh->pa_tail, pa);
- pa->transmission_time = GNUNET_TIME_absolute_get ();
- pa->message_size = pm->bytes_msg;
- GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
- "Waiting for ACKnowledgment `%s' for <%llu>\n",
- GNUNET_uuid2s (&pa->ack_uuid.value),
- pm->logging_uuid);
- return pa;
- }
- /**
- * Fragment the given @a pm to the given @a mtu. Adds
- * additional fragments to the neighbour as well. If the
- * @a mtu is too small, generates and error for the @a pm
- * and returns NULL.
- *
- * @param queue which queue to fragment for
- * @param dvh path the message will take, or NULL
- * @param pm pending message to fragment for transmission
- * @return new message to transmit
- */
- static struct PendingMessage *
- fragment_message (struct Queue *queue,
- struct DistanceVectorHop *dvh,
- struct PendingMessage *pm)
- {
- struct PendingAcknowledgement *pa;
- struct PendingMessage *ff;
- uint16_t mtu;
- mtu = (0 == queue->mtu)
- ? UINT16_MAX - sizeof(struct GNUNET_TRANSPORT_SendMessageTo)
- : queue->mtu;
- set_pending_message_uuid (pm);
- GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
- "Fragmenting message %llu <%llu> to %s for MTU %u\n",
- (unsigned long long) pm->msg_uuid.uuid,
- pm->logging_uuid,
- GNUNET_i2s (&pm->vl->target),
- (unsigned int) mtu);
- pa = prepare_pending_acknowledgement (queue, dvh, pm);
- /* This invariant is established in #handle_add_queue_message() */
- GNUNET_assert (mtu > sizeof(struct TransportFragmentBoxMessage));
- /* select fragment for transmission, descending the tree if it has
- been expanded until we are at a leaf or at a fragment that is small
- enough
- */
- ff = pm;
- while (((ff->bytes_msg > mtu) || (pm == ff)) &&
- (ff->frag_off == ff->bytes_msg) && (NULL != ff->head_frag))
- {
- ff = ff->head_frag; /* descent into fragmented fragments */
- }
- if (((ff->bytes_msg > mtu) || (pm == ff)) && (pm->frag_off < pm->bytes_msg))
- {
- /* Did not yet calculate all fragments, calculate next fragment */
- struct PendingMessage *frag;
- struct TransportFragmentBoxMessage tfb;
- const char *orig;
- char *msg;
- uint16_t fragmax;
- uint16_t fragsize;
- uint16_t msize;
- uint16_t xoff = 0;
- orig = (const char *) &ff[1];
- msize = ff->bytes_msg;
- if (pm != ff)
- {
- const struct TransportFragmentBoxMessage *tfbo;
- tfbo = (const struct TransportFragmentBoxMessage *) orig;
- orig += sizeof(struct TransportFragmentBoxMessage);
- msize -= sizeof(struct TransportFragmentBoxMessage);
- xoff = ntohs (tfbo->frag_off);
- }
- fragmax = mtu - sizeof(struct TransportFragmentBoxMessage);
- fragsize = GNUNET_MIN (msize - ff->frag_off, fragmax);
- frag =
- GNUNET_malloc (sizeof(struct PendingMessage)
- + sizeof(struct TransportFragmentBoxMessage) + fragsize);
- frag->logging_uuid = logging_uuid_gen++;
- frag->vl = pm->vl;
- frag->frag_parent = ff;
- frag->timeout = pm->timeout;
- frag->bytes_msg = sizeof(struct TransportFragmentBoxMessage) + fragsize;
- frag->pmt = PMT_FRAGMENT_BOX;
- msg = (char *) &frag[1];
- tfb.header.type = htons (GNUNET_MESSAGE_TYPE_TRANSPORT_FRAGMENT);
- tfb.header.size =
- htons (sizeof(struct TransportFragmentBoxMessage) + fragsize);
- tfb.ack_uuid = pa->ack_uuid;
- tfb.msg_uuid = pm->msg_uuid;
- tfb.frag_off = htons (ff->frag_off + xoff);
- tfb.msg_size = htons (pm->bytes_msg);
- memcpy (msg, &tfb, sizeof(tfb));
- memcpy (&msg[sizeof(tfb)], &orig[ff->frag_off], fragsize);
- GNUNET_CONTAINER_MDLL_insert (frag, ff->head_frag, ff->tail_frag, frag);
- ff->frag_off += fragsize;
- ff = frag;
- }
- /* Move head to the tail and return it */
- GNUNET_CONTAINER_MDLL_remove (frag,
- ff->frag_parent->head_frag,
- ff->frag_parent->tail_frag,
- ff);
- GNUNET_CONTAINER_MDLL_insert_tail (frag,
- ff->frag_parent->head_frag,
- ff->frag_parent->tail_frag,
- ff);
- return ff;
- }
- /**
- * Reliability-box the given @a pm. On error (can there be any), NULL
- * may be returned, otherwise the "replacement" for @a pm (which
- * should then be added to the respective neighbour's queue instead of
- * @a pm). If the @a pm is already fragmented or reliability boxed,
- * or itself an ACK, this function simply returns @a pm.
- *
- * @param queue which queue to prepare transmission for
- * @param dvh path the message will take, or NULL
- * @param pm pending message to box for transmission over unreliabile queue
- * @return new message to transmit
- */
- static struct PendingMessage *
- reliability_box_message (struct Queue *queue,
- struct DistanceVectorHop *dvh,
- struct PendingMessage *pm)
- {
- struct TransportReliabilityBoxMessage rbox;
- struct PendingAcknowledgement *pa;
- struct PendingMessage *bpm;
- char *msg;
- if (PMT_CORE != pm->pmt)
- return pm; /* already fragmented or reliability boxed, or control message:
- do nothing */
- if (NULL != pm->bpm)
- return pm->bpm; /* already computed earlier: do nothing */
- GNUNET_assert (NULL == pm->head_frag);
- if (pm->bytes_msg + sizeof(rbox) > UINT16_MAX)
- {
- /* failed hard */
- GNUNET_break (0);
- client_send_response (pm);
- return NULL;
- }
- GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
- "Preparing reliability box for message <%llu> to %s on queue %s\n",
- pm->logging_uuid,
- GNUNET_i2s (&pm->vl->target),
- queue->address);
- pa = prepare_pending_acknowledgement (queue, dvh, pm);
- bpm = GNUNET_malloc (sizeof(struct PendingMessage) + sizeof(rbox)
- + pm->bytes_msg);
- bpm->logging_uuid = logging_uuid_gen++;
- bpm->vl = pm->vl;
- bpm->frag_parent = pm;
- GNUNET_CONTAINER_MDLL_insert (frag, pm->head_frag, pm->tail_frag, bpm);
- bpm->timeout = pm->timeout;
- bpm->pmt = PMT_RELIABILITY_BOX;
- bpm->bytes_msg = pm->bytes_msg + sizeof(rbox);
- set_pending_message_uuid (bpm);
- rbox.header.type = htons (GNUNET_MESSAGE_TYPE_TRANSPORT_RELIABILITY_BOX);
- rbox.header.size = htons (sizeof(rbox) + pm->bytes_msg);
- rbox.ack_countdown = htonl (0); // FIXME: implement ACK countdown support
- rbox.ack_uuid = pa->ack_uuid;
- msg = (char *) &bpm[1];
- memcpy (msg, &rbox, sizeof(rbox));
- memcpy (&msg[sizeof(rbox)], &pm[1], pm->bytes_msg);
- pm->bpm = bpm;
- return bpm;
- }
- /**
- * Change the value of the `next_attempt` field of @a pm
- * to @a next_attempt and re-order @a pm in the transmission
- * list as required by the new timestmap.
- *
- * @param pm a pending message to update
- * @param next_attempt timestamp to use
- */
- static void
- update_pm_next_attempt (struct PendingMessage *pm,
- struct GNUNET_TIME_Absolute next_attempt)
- {
- struct VirtualLink *vl = pm->vl;
- pm->next_attempt = next_attempt;
- GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
- "Next attempt for message <%llu> set to %s\n",
- pm->logging_uuid,
- GNUNET_STRINGS_absolute_time_to_string (next_attempt));
- if (NULL == pm->frag_parent)
- {
- struct PendingMessage *pos;
- /* re-insert sort in neighbour list */
- GNUNET_CONTAINER_MDLL_remove (vl,
- vl->pending_msg_head,
- vl->pending_msg_tail,
- pm);
- pos = vl->pending_msg_tail;
- while ((NULL != pos) &&
- (next_attempt.abs_value_us > pos->next_attempt.abs_value_us))
- pos = pos->prev_vl;
- GNUNET_CONTAINER_MDLL_insert_after (vl,
- vl->pending_msg_head,
- vl->pending_msg_tail,
- pos,
- pm);
- }
- else
- {
- /* re-insert sort in fragment list */
- struct PendingMessage *fp = pm->frag_parent;
- struct PendingMessage *pos;
- GNUNET_CONTAINER_MDLL_remove (frag, fp->head_frag, fp->tail_frag, pm);
- pos = fp->tail_frag;
- while ((NULL != pos) &&
- (next_attempt.abs_value_us > pos->next_attempt.abs_value_us))
- pos = pos->prev_frag;
- GNUNET_CONTAINER_MDLL_insert_after (frag,
- fp->head_frag,
- fp->tail_frag,
- pos,
- pm);
- }
- }
- /**
- * Context for #select_best_pending_from_link().
- */
- struct PendingMessageScoreContext
- {
- /**
- * Set to the best message that was found, NULL for none.
- */
- struct PendingMessage *best;
- /**
- * DVH that @e best should take, or NULL for direct transmission.
- */
- struct DistanceVectorHop *dvh;
- /**
- * What is the estimated total overhead for this message?
- */
- size_t real_overhead;
- /**
- * Number of pending messages we seriously considered this time.
- */
- unsigned int consideration_counter;
- /**
- * Did we have to fragment?
- */
- int frag;
- /**
- * Did we have to reliability box?
- */
- int relb;
- };
- /**
- * Select the best pending message from @a vl for transmission
- * via @a queue.
- *
- * @param sc[in,out] best message so far (NULL for none), plus scoring data
- * @param queue the queue that will be used for transmission
- * @param vl the virtual link providing the messages
- * @param dvh path we are currently considering, or NULL for none
- * @param overhead number of bytes of overhead to be expected
- * from DV encapsulation (0 for without DV)
- */
- static void
- select_best_pending_from_link (struct PendingMessageScoreContext *sc,
- struct Queue *queue,
- struct VirtualLink *vl,
- struct DistanceVectorHop *dvh,
- size_t overhead)
- {
- struct GNUNET_TIME_Absolute now;
- now = GNUNET_TIME_absolute_get ();
- for (struct PendingMessage *pos = vl->pending_msg_head; NULL != pos;
- pos = pos->next_vl)
- {
- size_t real_overhead = overhead;
- int frag;
- int relb;
- if ((NULL != dvh) && (PMT_DV_BOX == pos->pmt))
- continue; /* DV messages must not be DV-routed to next hop! */
- if (pos->next_attempt.abs_value_us > now.abs_value_us)
- break; /* too early for all messages, they are sorted by next_attempt */
- if (NULL != pos->qe)
- continue; /* not eligible */
- sc->consideration_counter++;
- /* determine if we have to fragment, if so add fragmentation
- overhead! */
- frag = GNUNET_NO;
- if (((0 != queue->mtu) &&
- (pos->bytes_msg + real_overhead > queue->mtu)) ||
- (pos->bytes_msg > UINT16_MAX - sizeof(struct
- GNUNET_TRANSPORT_SendMessageTo))
- ||
- (NULL != pos->head_frag /* fragments already exist, should
- respect that even if MTU is 0 for
- this queue */))
- {
- frag = GNUNET_YES;
- if (GNUNET_TRANSPORT_CC_RELIABLE == queue->tc->details.communicator.cc)
- {
- /* FIXME-FRAG-REL-UUID: we could use an optimized, shorter fragmentation
- header without the ACK UUID when using a *reliable* channel! */
- }
- real_overhead = overhead + sizeof(struct TransportFragmentBoxMessage);
- }
- /* determine if we have to reliability-box, if so add reliability box
- overhead */
- relb = GNUNET_NO;
- if ((GNUNET_NO == frag) &&
- (0 == (pos->prefs & GNUNET_MQ_PREF_UNRELIABLE)) &&
- (GNUNET_TRANSPORT_CC_RELIABLE != queue->tc->details.communicator.cc))
- {
- relb = GNUNET_YES;
- real_overhead += sizeof(struct TransportReliabilityBoxMessage);
- }
- /* Finally, compare to existing 'best' in sc to see if this 'pos' pending
- message would beat it! */
- if (NULL != sc->best)
- {
- /* CHECK if pos fits queue BETTER (=smaller) than pm, if not: continue;
- OPTIMIZE-ME: This is a heuristic, which so far has NOT been
- experimentally validated. There may be some huge potential for
- improvement here. Also, we right now only compare how well the
- given message fits _this_ queue, and do not consider how well other
- queues might suit the message. Taking other queues into consideration
- may further improve the result, but could also be expensive
- in terms of CPU time. */long long sc_score = sc->frag * 40 + sc->relb * 20 + sc->real_overhead;
- long long pm_score = frag * 40 + relb * 20 + real_overhead;
- long long time_delta =
- (sc->best->next_attempt.abs_value_us - pos->next_attempt.abs_value_us)
- / 1000LL;
- /* "time_delta" considers which message has been 'ready' for transmission
- for longer, if a message has a preference for low latency, increase
- the weight of the time_delta by 10x if it is favorable for that message */
- if ((0 != (pos->prefs & GNUNET_MQ_PREF_LOW_LATENCY)) &&
- (0 != (sc->best->prefs & GNUNET_MQ_PREF_LOW_LATENCY)))
- time_delta *= 10; /* increase weight (always, both are low latency) */
- else if ((0 != (pos->prefs & GNUNET_MQ_PREF_LOW_LATENCY)) &&
- (time_delta > 0))
- time_delta *=
- 10; /* increase weight, favors 'pos', which is low latency */
- else if ((0 != (sc->best->prefs & GNUNET_MQ_PREF_LOW_LATENCY)) &&
- (time_delta < 0))
- time_delta *=
- 10; /* increase weight, favors 'sc->best', which is low latency */
- if (0 != queue->mtu)
- {
- /* Grant bonus if we are bellow MTU, larger bonus the closer we will
- be to the MTU */
- if (queue->mtu > sc->real_overhead + sc->best->bytes_msg)
- sc_score -= queue->mtu - (sc->real_overhead + sc->best->bytes_msg);
- if (queue->mtu > real_overhead + pos->bytes_msg)
- pm_score -= queue->mtu - (real_overhead + pos->bytes_msg);
- }
- if (sc_score + time_delta > pm_score)
- continue; /* sc_score larger, keep sc->best */
- }
- sc->best = pos;
- sc->dvh = dvh;
- sc->frag = frag;
- sc->relb = relb;
- }
- }
- /**
- * Function to call to further operate on the now DV encapsulated
- * message @a hdr, forwarding it via @a next_hop under respect of
- * @a options.
- *
- * @param cls a `struct PendingMessageScoreContext`
- * @param next_hop next hop of the DV path
- * @param hdr encapsulated message, technically a `struct TransportDFBoxMessage`
- * @param options options of the original message
- */
- static void
- extract_box_cb (void *cls,
- struct Neighbour *next_hop,
- const struct GNUNET_MessageHeader *hdr,
- enum RouteMessageOptions options)
- {
- struct PendingMessageScoreContext *sc = cls;
- struct PendingMessage *pm = sc->best;
- struct PendingMessage *bpm;
- uint16_t bsize = ntohs (hdr->size);
- GNUNET_assert (NULL == pm->bpm);
- bpm = GNUNET_malloc (sizeof(struct PendingMessage) + bsize);
- bpm->logging_uuid = logging_uuid_gen++;
- bpm->pmt = PMT_DV_BOX;
- GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
- "Creating DV Box %llu for original message %llu (next hop is %s)\n",
- bpm->logging_uuid,
- pm->logging_uuid,
- GNUNET_i2s (&next_hop->pid));
- memcpy (&bpm[1], hdr, bsize);
- pm->bpm = bpm;
- }
- /**
- * We believe we are ready to transmit a `struct PendingMessage` on a
- * queue, the big question is which one! We need to see if there is
- * one pending that is allowed by flow control and congestion control
- * and (ideally) matches our queue's performance profile.
- *
- * If such a message is found, we give the message to the communicator
- * for transmission (updating the tracker, and re-scheduling ourselves
- * if applicable).
- *
- * If no such message is found, the queue's `idle` field must be set
- * to #GNUNET_YES.
- *
- * @param cls the `struct Queue` to process transmissions for
- */
- static void
- transmit_on_queue (void *cls)
- {
- struct Queue *queue = cls;
- struct Neighbour *n = queue->neighbour;
- struct PendingMessageScoreContext sc;
- struct PendingMessage *pm;
- queue->transmit_task = NULL;
- if (NULL == n->vl)
- {
- GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
- "Virtual link `%s' is down, cannot have PM for queue `%s'\n",
- GNUNET_i2s (&n->pid),
- queue->address);
- queue->idle = GNUNET_YES;
- return;
- }
- memset (&sc, 0, sizeof(sc));
- select_best_pending_from_link (&sc, queue, n->vl, NULL, 0);
- if (NULL == sc.best)
- {
- /* Also look at DVH that have the n as first hop! */
- for (struct DistanceVectorHop *dvh = n->dv_head; NULL != dvh;
- dvh = dvh->next_neighbour)
- {
- select_best_pending_from_link (&sc,
- queue,
- dvh->dv->vl,
- dvh,
- sizeof(struct GNUNET_PeerIdentity)
- * (1 + dvh->distance)
- + sizeof(struct TransportDVBoxMessage)
- + sizeof(struct TransportDVBoxPayloadP));
- }
- }
- if (NULL == sc.best)
- {
- /* no message pending, nothing to do here! */
- GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
- "No pending messages, queue `%s' to %s now idle\n",
- queue->address,
- GNUNET_i2s (&n->pid));
- queue->idle = GNUNET_YES;
- return;
- }
- /* Given selection in `sc`, do transmission */
- pm = sc.best;
- if (NULL != sc.dvh)
- {
- GNUNET_assert (PMT_DV_BOX != pm->pmt);
- if (NULL != sc.best->bpm)
- {
- /* We did this boxing before, but possibly for a different path!
- Discard old DV box! OPTIMIZE-ME: we might want to check if
- it is the same and then not re-build the message... */
- free_pending_message (sc.best->bpm);
- sc.best->bpm = NULL;
- }
- encapsulate_for_dv (sc.dvh->dv,
- 1,
- &sc.dvh,
- (const struct GNUNET_MessageHeader *) &sc.best[1],
- &extract_box_cb,
- &sc,
- RMO_NONE);
- GNUNET_assert (NULL != sc.best->bpm);
- pm = sc.best->bpm;
- }
- if (GNUNET_YES == sc.frag)
- {
- pm = fragment_message (queue, sc.dvh, pm);
- if (NULL == pm)
- {
- GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
- "Fragmentation failed queue %s to %s for <%llu>, trying again\n",
- queue->address,
- GNUNET_i2s (&n->pid),
- sc.best->logging_uuid);
- schedule_transmit_on_queue (queue, GNUNET_SCHEDULER_PRIORITY_DEFAULT);
- return;
- }
- }
- else if (GNUNET_YES == sc.relb)
- {
- pm = reliability_box_message (queue, sc.dvh, pm);
- if (NULL == pm)
- {
- /* Reliability boxing failed, try next message... */
- GNUNET_log (
- GNUNET_ERROR_TYPE_DEBUG,
- "Reliability boxing failed queue %s to %s for <%llu>, trying again\n",
- queue->address,
- GNUNET_i2s (&n->pid),
- sc.best->logging_uuid);
- schedule_transmit_on_queue (queue, GNUNET_SCHEDULER_PRIORITY_DEFAULT);
- return;
- }
- }
- /* Pass 'pm' for transission to the communicator */
- GNUNET_log (
- GNUNET_ERROR_TYPE_DEBUG,
- "Passing message <%llu> to queue %s for peer %s (considered %u others)\n",
- pm->logging_uuid,
- queue->address,
- GNUNET_i2s (&n->pid),
- sc.consideration_counter);
- /* Flow control: increment amount of traffic sent; if we are routing
- via DV (and thus the ultimate target of the pending message is for
- a different virtual link than the one of the queue), then we need
- to use up not only the window of the direct link but also the
- flow control window for the DV link! */pm->vl->outbound_fc_window_size_used += pm->bytes_msg;
- if (pm->vl != queue->neighbour->vl)
- {
- /* If the virtual link of the queue differs, this better be distance
- vector routing! */
- GNUNET_assert (NULL != sc.dvh);
- /* If we do distance vector routing, we better not do this for a
- message that was itself DV-routed */
- GNUNET_assert (PMT_DV_BOX != sc.best->pmt);
- /* We use the size of the unboxed message here, to avoid counting
- the DV-Box header which is eaten up on the way by intermediaries */
- queue->neighbour->vl->outbound_fc_window_size_used += sc.best->bytes_msg;
- }
- else
- {
- GNUNET_assert (NULL == sc.dvh);
- }
- queue_send_msg (queue, pm, &pm[1], pm->bytes_msg);
- /* Check if this transmission somehow conclusively finished handing 'pm'
- even without any explicit ACKs */
- if ((PMT_CORE == pm->pmt) ||
- (GNUNET_TRANSPORT_CC_RELIABLE == queue->tc->details.communicator.cc))
- {
- completed_pending_message (pm);
- }
- else
- {
- /* Message not finished, waiting for acknowledgement.
- Update time by which we might retransmit 's' based on queue
- characteristics (i.e. RTT); it takes one RTT for the message to
- arrive and the ACK to come back in the best case; but the other
- side is allowed to delay ACKs by 2 RTTs, so we use 4 RTT before
- retransmitting.
- OPTIMIZE: Note that in the future this heuristic should likely
- be improved further (measure RTT stability, consider message
- urgency and size when delaying ACKs, etc.) */update_pm_next_attempt (pm,
- GNUNET_TIME_relative_to_absolute (
- GNUNET_TIME_relative_multiply (queue->pd.aged_rtt,
- 4)));
- }
- /* finally, re-schedule queue transmission task itself */
- schedule_transmit_on_queue (queue, GNUNET_SCHEDULER_PRIORITY_DEFAULT);
- }
- /**
- * Queue to a peer went down. Process the request.
- *
- * @param cls the client
- * @param dqm the send message that was sent
- */
- static void
- handle_del_queue_message (void *cls,
- const struct GNUNET_TRANSPORT_DelQueueMessage *dqm)
- {
- struct TransportClient *tc = cls;
- if (CT_COMMUNICATOR != tc->type)
- {
- GNUNET_break (0);
- GNUNET_SERVICE_client_drop (tc->client);
- return;
- }
- for (struct Queue *queue = tc->details.communicator.queue_head; NULL != queue;
- queue = queue->next_client)
- {
- struct Neighbour *neighbour = queue->neighbour;
- if ((dqm->qid != queue->qid) ||
- (0 != GNUNET_memcmp (&dqm->receiver, &neighbour->pid)))
- continue;
- GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
- "Dropped queue %s to peer %s\n",
- queue->address,
- GNUNET_i2s (&neighbour->pid));
- free_queue (queue);
- GNUNET_SERVICE_client_continue (tc->client);
- return;
- }
- GNUNET_break (0);
- GNUNET_SERVICE_client_drop (tc->client);
- }
- /**
- * Message was transmitted. Process the request.
- *
- * @param cls the client
- * @param sma the send message that was sent
- */
- static void
- handle_send_message_ack (void *cls,
- const struct GNUNET_TRANSPORT_SendMessageToAck *sma)
- {
- struct TransportClient *tc = cls;
- struct QueueEntry *qe;
- struct PendingMessage *pm;
- if (CT_COMMUNICATOR != tc->type)
- {
- GNUNET_break (0);
- GNUNET_SERVICE_client_drop (tc->client);
- return;
- }
- /* find our queue entry matching the ACK */
- qe = NULL;
- for (struct Queue *queue = tc->details.communicator.queue_head; NULL != queue;
- queue = queue->next_client)
- {
- if (0 != GNUNET_memcmp (&queue->neighbour->pid, &sma->receiver))
- continue;
- for (struct QueueEntry *qep = queue->queue_head; NULL != qep;
- qep = qep->next)
- {
- if (qep->mid != sma->mid)
- continue;
- qe = qep;
- break;
- }
- break;
- }
- if (NULL == qe)
- {
- /* this should never happen */
- GNUNET_break (0);
- GNUNET_SERVICE_client_drop (tc->client);
- return;
- }
- GNUNET_CONTAINER_DLL_remove (qe->queue->queue_head,
- qe->queue->queue_tail,
- qe);
- qe->queue->queue_length--;
- tc->details.communicator.total_queue_length--;
- GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
- "Received ACK on queue %s to peer %s (new length: %u/%u)\n",
- qe->queue->address,
- GNUNET_i2s (&qe->queue->neighbour->pid),
- qe->queue->queue_length,
- tc->details.communicator.total_queue_length);
- GNUNET_SERVICE_client_continue (tc->client);
- /* if applicable, resume transmissions that waited on ACK */
- if (COMMUNICATOR_TOTAL_QUEUE_LIMIT - 1 ==
- tc->details.communicator.total_queue_length)
- {
- /* Communicator dropped below threshold, resume all queues
- incident with this client! */
- GNUNET_STATISTICS_update (
- GST_stats,
- "# Transmission throttled due to communicator queue limit",
- -1,
- GNUNET_NO);
- for (struct Queue *queue = tc->details.communicator.queue_head;
- NULL != queue;
- queue = queue->next_client)
- schedule_transmit_on_queue (queue, GNUNET_SCHEDULER_PRIORITY_DEFAULT);
- }
- else if (QUEUE_LENGTH_LIMIT - 1 == qe->queue->queue_length)
- {
- /* queue dropped below threshold; only resume this one queue */
- GNUNET_STATISTICS_update (GST_stats,
- "# Transmission throttled due to queue queue limit",
- -1,
- GNUNET_NO);
- schedule_transmit_on_queue (qe->queue, GNUNET_SCHEDULER_PRIORITY_DEFAULT);
- }
- if (NULL != (pm = qe->pm))
- {
- struct VirtualLink *vl;
- GNUNET_assert (qe == pm->qe);
- pm->qe = NULL;
- /* If waiting for this communicator may have blocked transmission
- of pm on other queues for this neighbour, force schedule
- transmit on queue for queues of the neighbour */
- vl = pm->vl;
- if (vl->pending_msg_head == pm)
- check_vl_transmission (vl);
- }
- GNUNET_free (qe);
- }
- /**
- * Iterator telling new MONITOR client about all existing
- * queues to peers.
- *
- * @param cls the new `struct TransportClient`
- * @param pid a connected peer
- * @param value the `struct Neighbour` with more information
- * @return #GNUNET_OK (continue to iterate)
- */
- static int
- notify_client_queues (void *cls,
- const struct GNUNET_PeerIdentity *pid,
- void *value)
- {
- struct TransportClient *tc = cls;
- struct Neighbour *neighbour = value;
- GNUNET_assert (CT_MONITOR == tc->type);
- for (struct Queue *q = neighbour->queue_head; NULL != q;
- q = q->next_neighbour)
- {
- struct MonitorEvent me = { .rtt = q->pd.aged_rtt,
- .cs = q->cs,
- .num_msg_pending = q->num_msg_pending,
- .num_bytes_pending = q->num_bytes_pending };
- notify_monitor (tc, pid, q->address, q->nt, &me);
- }
- return GNUNET_OK;
- }
- /**
- * Initialize a monitor client.
- *
- * @param cls the client
- * @param start the start message that was sent
- */
- static void
- handle_monitor_start (void *cls,
- const struct GNUNET_TRANSPORT_MonitorStart *start)
- {
- struct TransportClient *tc = cls;
- if (CT_NONE != tc->type)
- {
- GNUNET_break (0);
- GNUNET_SERVICE_client_drop (tc->client);
- return;
- }
- tc->type = CT_MONITOR;
- tc->details.monitor.peer = start->peer;
- tc->details.monitor.one_shot = ntohl (start->one_shot);
- GNUNET_CONTAINER_multipeermap_iterate (neighbours, ¬ify_client_queues, tc);
- GNUNET_SERVICE_client_mark_monitor (tc->client);
- GNUNET_SERVICE_client_continue (tc->client);
- }
- /**
- * Find transport client providing communication service
- * for the protocol @a prefix.
- *
- * @param prefix communicator name
- * @return NULL if no such transport client is available
- */
- static struct TransportClient *
- lookup_communicator (const char *prefix)
- {
- for (struct TransportClient *tc = clients_head; NULL != tc; tc = tc->next)
- {
- if (CT_COMMUNICATOR != tc->type)
- continue;
- if (0 == strcmp (prefix, tc->details.communicator.address_prefix))
- return tc;
- }
- GNUNET_log (
- GNUNET_ERROR_TYPE_WARNING,
- "Somone suggested use of communicator for `%s', but we do not have such a communicator!\n",
- prefix);
- return NULL;
- }
- /**
- * Signature of a function called with a communicator @a address of a peer
- * @a pid that an application wants us to connect to.
- *
- * @param pid target peer
- * @param address the address to try
- */
- static void
- suggest_to_connect (const struct GNUNET_PeerIdentity *pid, const char *address)
- {
- static uint32_t idgen;
- struct TransportClient *tc;
- char *prefix;
- struct GNUNET_TRANSPORT_CreateQueue *cqm;
- struct GNUNET_MQ_Envelope *env;
- size_t alen;
- prefix = GNUNET_HELLO_address_to_prefix (address);
- if (NULL == prefix)
- {
- GNUNET_break (0); /* We got an invalid address!? */
- return;
- }
- tc = lookup_communicator (prefix);
- if (NULL == tc)
- {
- GNUNET_STATISTICS_update (GST_stats,
- "# Suggestions ignored due to missing communicator",
- 1,
- GNUNET_NO);
- GNUNET_log (GNUNET_ERROR_TYPE_INFO,
- "Cannot connect to %s at `%s', no matching communicator present\n",
- GNUNET_i2s (pid),
- address);
- GNUNET_free (prefix);
- return;
- }
- /* forward suggestion for queue creation to communicator */
- GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
- "Request #%u for `%s' communicator to create queue to `%s'\n",
- (unsigned int) idgen,
- prefix,
- address);
- GNUNET_free (prefix);
- alen = strlen (address) + 1;
- env =
- GNUNET_MQ_msg_extra (cqm, alen, GNUNET_MESSAGE_TYPE_TRANSPORT_QUEUE_CREATE);
- cqm->request_id = htonl (idgen++);
- cqm->receiver = *pid;
- memcpy (&cqm[1], address, alen);
- GNUNET_MQ_send (tc->mq, env);
- }
- /**
- * The queue @a q (which matches the peer and address in @a vs) is
- * ready for queueing. We should now queue the validation request.
- *
- * @param q queue to send on
- * @param vs state to derive validation challenge from
- */
- static void
- validation_transmit_on_queue (struct Queue *q, struct ValidationState *vs)
- {
- struct TransportValidationChallengeMessage tvc;
- vs->last_challenge_use = GNUNET_TIME_absolute_get_monotonic (GST_cfg);
- tvc.header.type =
- htons (GNUNET_MESSAGE_TYPE_TRANSPORT_ADDRESS_VALIDATION_CHALLENGE);
- tvc.header.size = htons (sizeof(tvc));
- tvc.reserved = htonl (0);
- tvc.challenge = vs->challenge;
- tvc.sender_time = GNUNET_TIME_absolute_hton (vs->last_challenge_use);
- GNUNET_log (GNUNET_ERROR_TYPE_INFO,
- "Sending address validation challenge %s to %s\n",
- GNUNET_sh2s (&tvc.challenge.value),
- GNUNET_i2s (&q->neighbour->pid));
- queue_send_msg (q, NULL, &tvc, sizeof(tvc));
- }
- /**
- * Task run periodically to validate some address based on #validation_heap.
- *
- * @param cls NULL
- */
- static void
- validation_start_cb (void *cls)
- {
- struct ValidationState *vs;
- struct Queue *q;
- (void) cls;
- validation_task = NULL;
- vs = GNUNET_CONTAINER_heap_peek (validation_heap);
- /* drop validations past their expiration */
- while (
- (NULL != vs) &&
- (0 == GNUNET_TIME_absolute_get_remaining (vs->valid_until).rel_value_us))
- {
- free_validation_state (vs);
- vs = GNUNET_CONTAINER_heap_peek (validation_heap);
- }
- if (NULL == vs)
- {
- GNUNET_log (GNUNET_ERROR_TYPE_INFO,
- "Address validation task not scheduled anymore, nothing to do\n");
- return; /* woopsie, no more addresses known, should only
- happen if we're really a lonely peer */
- }
- q = find_queue (&vs->pid, vs->address);
- if (NULL == q)
- {
- vs->awaiting_queue = GNUNET_YES;
- suggest_to_connect (&vs->pid, vs->address);
- }
- else
- validation_transmit_on_queue (q, vs);
- /* Finally, reschedule next attempt */
- vs->challenge_backoff =
- GNUNET_TIME_randomized_backoff (vs->challenge_backoff,
- MAX_VALIDATION_CHALLENGE_FREQ);
- GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
- "Address validation task will run again in %s\n",
- GNUNET_STRINGS_relative_time_to_string (vs->challenge_backoff,
- GNUNET_YES));
- update_next_challenge_time (vs,
- GNUNET_TIME_relative_to_absolute (
- vs->challenge_backoff));
- }
- /**
- * Closure for #check_connection_quality.
- */
- struct QueueQualityContext
- {
- /**
- * Set to the @e k'th queue encountered.
- */
- struct Queue *q;
- /**
- * Set to the number of quality queues encountered.
- */
- unsigned int quality_count;
- /**
- * Set to the total number of queues encountered.
- */
- unsigned int num_queues;
- /**
- * Decremented for each queue, for selection of the
- * k-th queue in @e q.
- */
- unsigned int k;
- };
- /**
- * Check whether any queue to the given neighbour is
- * of a good "quality" and if so, increment the counter.
- * Also counts the total number of queues, and returns
- * the k-th queue found.
- *
- * @param cls a `struct QueueQualityContext *` with counters
- * @param pid peer this is about
- * @param value a `struct Neighbour`
- * @return #GNUNET_OK (continue to iterate)
- */
- static int
- check_connection_quality (void *cls,
- const struct GNUNET_PeerIdentity *pid,
- void *value)
- {
- struct QueueQualityContext *ctx = cls;
- struct Neighbour *n = value;
- int do_inc;
- (void) pid;
- do_inc = GNUNET_NO;
- for (struct Queue *q = n->queue_head; NULL != q; q = q->next_neighbour)
- {
- ctx->num_queues++;
- if (0 == ctx->k--)
- ctx->q = q;
- /* FIXME-CONQ-STATISTICS: in the future, add reliability / goodput
- statistics and consider those as well here? */
- if (q->pd.aged_rtt.rel_value_us < DV_QUALITY_RTT_THRESHOLD.rel_value_us)
- do_inc = GNUNET_YES;
- }
- if (GNUNET_YES == do_inc)
- ctx->quality_count++;
- return GNUNET_OK;
- }
- /**
- * Task run when we CONSIDER initiating a DV learn
- * process. We first check that sending out a message is
- * even possible (queues exist), then that it is desirable
- * (if not, reschedule the task for later), and finally
- * we may then begin the job. If there are too many
- * entries in the #dvlearn_map, we purge the oldest entry
- * using #lle_tail.
- *
- * @param cls NULL
- */
- static void
- start_dv_learn (void *cls)
- {
- struct LearnLaunchEntry *lle;
- struct QueueQualityContext qqc;
- struct TransportDVLearnMessage dvl;
- (void) cls;
- dvlearn_task = NULL;
- if (0 == GNUNET_CONTAINER_multipeermap_size (neighbours))
- return; /* lost all connectivity, cannot do learning */
- qqc.quality_count = 0;
- qqc.num_queues = 0;
- GNUNET_CONTAINER_multipeermap_iterate (neighbours,
- &check_connection_quality,
- &qqc);
- if (qqc.quality_count > DV_LEARN_QUALITY_THRESHOLD)
- {
- struct GNUNET_TIME_Relative delay;
- unsigned int factor;
- /* scale our retries by how far we are above the threshold */
- factor = qqc.quality_count / DV_LEARN_QUALITY_THRESHOLD;
- delay = GNUNET_TIME_relative_multiply (DV_LEARN_BASE_FREQUENCY, factor);
- GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
- "At connection quality %u, will launch DV learn in %s\n",
- qqc.quality_count,
- GNUNET_STRINGS_relative_time_to_string (delay, GNUNET_YES));
- dvlearn_task = GNUNET_SCHEDULER_add_delayed (delay, &start_dv_learn, NULL);
- return;
- }
- /* remove old entries in #dvlearn_map if it has grown too big */
- while (MAX_DV_LEARN_PENDING >=
- GNUNET_CONTAINER_multishortmap_size (dvlearn_map))
- {
- lle = lle_tail;
- GNUNET_assert (GNUNET_YES ==
- GNUNET_CONTAINER_multishortmap_remove (dvlearn_map,
- &lle->challenge.value,
- lle));
- GNUNET_CONTAINER_DLL_remove (lle_head, lle_tail, lle);
- GNUNET_free (lle);
- }
- /* setup data structure for learning */
- lle = GNUNET_new (struct LearnLaunchEntry);
- GNUNET_CRYPTO_random_block (GNUNET_CRYPTO_QUALITY_NONCE,
- &lle->challenge,
- sizeof(lle->challenge));
- GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
- "Starting launch DV learn with challenge %s\n",
- GNUNET_sh2s (&lle->challenge.value));
- GNUNET_CONTAINER_DLL_insert (lle_head, lle_tail, lle);
- GNUNET_break (GNUNET_YES ==
- GNUNET_CONTAINER_multishortmap_put (
- dvlearn_map,
- &lle->challenge.value,
- lle,
- GNUNET_CONTAINER_MULTIHASHMAPOPTION_UNIQUE_ONLY));
- dvl.header.type = htons (GNUNET_MESSAGE_TYPE_TRANSPORT_DV_LEARN);
- dvl.header.size = htons (sizeof(dvl));
- dvl.num_hops = htons (0);
- dvl.bidirectional = htons (0);
- dvl.non_network_delay = GNUNET_TIME_relative_hton (GNUNET_TIME_UNIT_ZERO);
- dvl.monotonic_time =
- GNUNET_TIME_absolute_hton (GNUNET_TIME_absolute_get_monotonic (GST_cfg));
- {
- struct DvInitPS dvip = {
- .purpose.purpose = htonl (
- GNUNET_SIGNATURE_PURPOSE_TRANSPORT_DV_INITIATOR),
- .purpose.size = htonl (sizeof(dvip)),
- .monotonic_time = dvl.monotonic_time,
- .challenge = lle->challenge
- };
- GNUNET_CRYPTO_eddsa_sign (GST_my_private_key,
- &dvip,
- &dvl.init_sig);
- }
- dvl.initiator = GST_my_identity;
- dvl.challenge = lle->challenge;
- qqc.quality_count = 0;
- qqc.k = GNUNET_CRYPTO_random_u32 (GNUNET_CRYPTO_QUALITY_WEAK, qqc.num_queues);
- qqc.num_queues = 0;
- qqc.q = NULL;
- GNUNET_CONTAINER_multipeermap_iterate (neighbours,
- &check_connection_quality,
- &qqc);
- GNUNET_assert (NULL != qqc.q);
- /* Do this as close to transmission time as possible! */
- lle->launch_time = GNUNET_TIME_absolute_get ();
- queue_send_msg (qqc.q, NULL, &dvl, sizeof(dvl));
- /* reschedule this job, randomizing the time it runs (but no
- actual backoff!) */
- dvlearn_task = GNUNET_SCHEDULER_add_delayed (GNUNET_TIME_randomize (
- DV_LEARN_BASE_FREQUENCY),
- &start_dv_learn,
- NULL);
- }
- /**
- * A new queue has been created, check if any address validation
- * requests have been waiting for it.
- *
- * @param cls a `struct Queue`
- * @param pid peer concerned (unused)
- * @param value a `struct ValidationState`
- * @return #GNUNET_NO if a match was found and we can stop looking
- */
- static int
- check_validation_request_pending (void *cls,
- const struct GNUNET_PeerIdentity *pid,
- void *value)
- {
- struct Queue *q = cls;
- struct ValidationState *vs = value;
- (void) pid;
- if ((GNUNET_YES == vs->awaiting_queue) &&
- (0 == strcmp (vs->address, q->address)))
- {
- vs->awaiting_queue = GNUNET_NO;
- validation_transmit_on_queue (q, vs);
- return GNUNET_NO;
- }
- return GNUNET_OK;
- }
- /**
- * Function called with the monotonic time of a DV initiator
- * by PEERSTORE. Updates the time.
- *
- * @param cls a `struct Neighbour`
- * @param record the information found, NULL for the last call
- * @param emsg error message
- */
- static void
- neighbour_dv_monotime_cb (void *cls,
- const struct GNUNET_PEERSTORE_Record *record,
- const char *emsg)
- {
- struct Neighbour *n = cls;
- struct GNUNET_TIME_AbsoluteNBO *mtbe;
- (void) emsg;
- if (NULL == record)
- {
- /* we're done with #neighbour_dv_monotime_cb() invocations,
- continue normal processing */
- n->get = NULL;
- n->dv_monotime_available = GNUNET_YES;
- return;
- }
- if (sizeof(*mtbe) != record->value_size)
- {
- GNUNET_break (0);
- return;
- }
- mtbe = record->value;
- n->last_dv_learn_monotime =
- GNUNET_TIME_absolute_max (n->last_dv_learn_monotime,
- GNUNET_TIME_absolute_ntoh (*mtbe));
- }
- /**
- * New queue became available. Process the request.
- *
- * @param cls the client
- * @param aqm the send message that was sent
- */
- static void
- handle_add_queue_message (void *cls,
- const struct GNUNET_TRANSPORT_AddQueueMessage *aqm)
- {
- struct TransportClient *tc = cls;
- struct Queue *queue;
- struct Neighbour *neighbour;
- const char *addr;
- uint16_t addr_len;
- if (ntohl (aqm->mtu) <= sizeof(struct TransportFragmentBoxMessage))
- {
- /* MTU so small as to be useless for transmissions,
- required for #fragment_message()! */
- GNUNET_break_op (0);
- GNUNET_SERVICE_client_drop (tc->client);
- return;
- }
- neighbour = lookup_neighbour (&aqm->receiver);
- if (NULL == neighbour)
- {
- neighbour = GNUNET_new (struct Neighbour);
- neighbour->pid = aqm->receiver;
- GNUNET_assert (GNUNET_OK ==
- GNUNET_CONTAINER_multipeermap_put (
- neighbours,
- &neighbour->pid,
- neighbour,
- GNUNET_CONTAINER_MULTIHASHMAPOPTION_UNIQUE_ONLY));
- neighbour->get =
- GNUNET_PEERSTORE_iterate (peerstore,
- "transport",
- &neighbour->pid,
- GNUNET_PEERSTORE_TRANSPORT_DVLEARN_MONOTIME,
- &neighbour_dv_monotime_cb,
- neighbour);
- }
- addr_len = ntohs (aqm->header.size) - sizeof(*aqm);
- addr = (const char *) &aqm[1];
- GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
- "New queue %s to %s available with QID %llu\n",
- addr,
- GNUNET_i2s (&aqm->receiver),
- (unsigned long long) aqm->qid);
- queue = GNUNET_malloc (sizeof(struct Queue) + addr_len);
- queue->tc = tc;
- queue->address = (const char *) &queue[1];
- queue->pd.aged_rtt = GNUNET_TIME_UNIT_FOREVER_REL;
- queue->qid = aqm->qid;
- queue->mtu = ntohl (aqm->mtu);
- queue->nt = (enum GNUNET_NetworkType) ntohl (aqm->nt);
- queue->cs = (enum GNUNET_TRANSPORT_ConnectionStatus) ntohl (aqm->cs);
- queue->neighbour = neighbour;
- queue->idle = GNUNET_YES;
- memcpy (&queue[1], addr, addr_len);
- /* notify monitors about new queue */
- {
- struct MonitorEvent me = { .rtt = queue->pd.aged_rtt, .cs = queue->cs };
- notify_monitors (&neighbour->pid, queue->address, queue->nt, &me);
- }
- GNUNET_CONTAINER_MDLL_insert (neighbour,
- neighbour->queue_head,
- neighbour->queue_tail,
- queue);
- GNUNET_CONTAINER_MDLL_insert (client,
- tc->details.communicator.queue_head,
- tc->details.communicator.queue_tail,
- queue);
- /* check if valdiations are waiting for the queue */
- (void)
- GNUNET_CONTAINER_multipeermap_get_multiple (validation_map,
- &aqm->receiver,
- &check_validation_request_pending,
- queue);
- /* look for traffic for this queue */
- schedule_transmit_on_queue (queue, GNUNET_SCHEDULER_PRIORITY_DEFAULT);
- /* might be our first queue, try launching DV learning */
- if (NULL == dvlearn_task)
- dvlearn_task = GNUNET_SCHEDULER_add_now (&start_dv_learn, NULL);
- GNUNET_SERVICE_client_continue (tc->client);
- }
- /**
- * Communicator tells us that our request to create a queue "worked", that
- * is setting up the queue is now in process.
- *
- * @param cls the `struct TransportClient`
- * @param cqr confirmation message
- */
- static void
- handle_queue_create_ok (void *cls,
- const struct GNUNET_TRANSPORT_CreateQueueResponse *cqr)
- {
- struct TransportClient *tc = cls;
- if (CT_COMMUNICATOR != tc->type)
- {
- GNUNET_break (0);
- GNUNET_SERVICE_client_drop (tc->client);
- return;
- }
- GNUNET_STATISTICS_update (GST_stats,
- "# Suggestions succeeded at communicator",
- 1,
- GNUNET_NO);
- GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
- "Request #%u for communicator to create queue succeeded\n",
- (unsigned int) ntohs (cqr->request_id));
- GNUNET_SERVICE_client_continue (tc->client);
- }
- /**
- * Communicator tells us that our request to create a queue failed. This
- * usually indicates that the provided address is simply invalid or that the
- * communicator's resources are exhausted.
- *
- * @param cls the `struct TransportClient`
- * @param cqr failure message
- */
- static void
- handle_queue_create_fail (
- void *cls,
- const struct GNUNET_TRANSPORT_CreateQueueResponse *cqr)
- {
- struct TransportClient *tc = cls;
- if (CT_COMMUNICATOR != tc->type)
- {
- GNUNET_break (0);
- GNUNET_SERVICE_client_drop (tc->client);
- return;
- }
- GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
- "Request #%u for communicator to create queue failed\n",
- (unsigned int) ntohs (cqr->request_id));
- GNUNET_STATISTICS_update (GST_stats,
- "# Suggestions failed in queue creation at communicator",
- 1,
- GNUNET_NO);
- GNUNET_SERVICE_client_continue (tc->client);
- }
- /**
- * We have received a `struct ExpressPreferenceMessage` from an application
- * client.
- *
- * @param cls handle to the client
- * @param msg the start message
- */
- static void
- handle_suggest_cancel (void *cls, const struct ExpressPreferenceMessage *msg)
- {
- struct TransportClient *tc = cls;
- struct PeerRequest *pr;
- if (CT_APPLICATION != tc->type)
- {
- GNUNET_break (0);
- GNUNET_SERVICE_client_drop (tc->client);
- return;
- }
- pr = GNUNET_CONTAINER_multipeermap_get (tc->details.application.requests,
- &msg->peer);
- if (NULL == pr)
- {
- GNUNET_break (0);
- GNUNET_SERVICE_client_drop (tc->client);
- return;
- }
- (void) stop_peer_request (tc, &pr->pid, pr);
- GNUNET_SERVICE_client_continue (tc->client);
- }
- /**
- * Function called by PEERSTORE for each matching record.
- *
- * @param cls closure, a `struct PeerRequest`
- * @param record peerstore record information
- * @param emsg error message, or NULL if no errors
- */
- static void
- handle_hello_for_client (void *cls,
- const struct GNUNET_PEERSTORE_Record *record,
- const char *emsg)
- {
- struct PeerRequest *pr = cls;
- const char *val;
- if (NULL != emsg)
- {
- GNUNET_log (GNUNET_ERROR_TYPE_WARNING,
- "Got failure from PEERSTORE: %s\n",
- emsg);
- return;
- }
- val = record->value;
- if ((0 == record->value_size) || ('\0' != val[record->value_size - 1]))
- {
- GNUNET_break (0);
- return;
- }
- start_address_validation (&pr->pid, (const char *) record->value);
- }
- /**
- * We have received a `struct ExpressPreferenceMessage` from an application
- * client.
- *
- * @param cls handle to the client
- * @param msg the start message
- */
- static void
- handle_suggest (void *cls, const struct ExpressPreferenceMessage *msg)
- {
- struct TransportClient *tc = cls;
- struct PeerRequest *pr;
- if (CT_NONE == tc->type)
- {
- tc->type = CT_APPLICATION;
- tc->details.application.requests =
- GNUNET_CONTAINER_multipeermap_create (16, GNUNET_YES);
- }
- if (CT_APPLICATION != tc->type)
- {
- GNUNET_break (0);
- GNUNET_SERVICE_client_drop (tc->client);
- return;
- }
- GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
- "Client suggested we talk to %s with preference %d at rate %u\n",
- GNUNET_i2s (&msg->peer),
- (int) ntohl (msg->pk),
- (int) ntohl (msg->bw.value__));
- pr = GNUNET_new (struct PeerRequest);
- pr->tc = tc;
- pr->pid = msg->peer;
- pr->bw = msg->bw;
- pr->pk = (enum GNUNET_MQ_PriorityPreferences) ntohl (msg->pk);
- if (GNUNET_YES != GNUNET_CONTAINER_multipeermap_put (
- tc->details.application.requests,
- &pr->pid,
- pr,
- GNUNET_CONTAINER_MULTIHASHMAPOPTION_UNIQUE_ONLY))
- {
- GNUNET_break (0);
- GNUNET_free (pr);
- GNUNET_SERVICE_client_drop (tc->client);
- return;
- }
- pr->wc = GNUNET_PEERSTORE_watch (peerstore,
- "transport",
- &pr->pid,
- GNUNET_PEERSTORE_TRANSPORT_URLADDRESS_KEY,
- &handle_hello_for_client,
- pr);
- GNUNET_SERVICE_client_continue (tc->client);
- }
- /**
- * Check #GNUNET_MESSAGE_TYPE_TRANSPORT_REQUEST_HELLO_VALIDATION
- * messages.
- *
- * @param cls a `struct TransportClient *`
- * @param m message to verify
- * @return #GNUNET_OK on success
- */
- static int
- check_request_hello_validation (void *cls,
- const struct RequestHelloValidationMessage *m)
- {
- (void) cls;
- GNUNET_MQ_check_zero_termination (m);
- return GNUNET_OK;
- }
- /**
- * A client encountered an address of another peer. Consider validating it,
- * and if validation succeeds, persist it to PEERSTORE.
- *
- * @param cls a `struct TransportClient *`
- * @param m message to verify
- */
- static void
- handle_request_hello_validation (void *cls,
- const struct RequestHelloValidationMessage *m)
- {
- struct TransportClient *tc = cls;
- start_address_validation (&m->peer, (const char *) &m[1]);
- GNUNET_SERVICE_client_continue (tc->client);
- }
- /**
- * Free neighbour entry.
- *
- * @param cls NULL
- * @param pid unused
- * @param value a `struct Neighbour`
- * @return #GNUNET_OK (always)
- */
- static int
- free_neighbour_cb (void *cls,
- const struct GNUNET_PeerIdentity *pid,
- void *value)
- {
- struct Neighbour *neighbour = value;
- (void) cls;
- (void) pid;
- GNUNET_break (0); // should this ever happen?
- free_neighbour (neighbour);
- return GNUNET_OK;
- }
- /**
- * Free DV route entry.
- *
- * @param cls NULL
- * @param pid unused
- * @param value a `struct DistanceVector`
- * @return #GNUNET_OK (always)
- */
- static int
- free_dv_routes_cb (void *cls,
- const struct GNUNET_PeerIdentity *pid,
- void *value)
- {
- struct DistanceVector *dv = value;
- (void) cls;
- (void) pid;
- free_dv_route (dv);
- return GNUNET_OK;
- }
- /**
- * Free validation state.
- *
- * @param cls NULL
- * @param pid unused
- * @param value a `struct ValidationState`
- * @return #GNUNET_OK (always)
- */
- static int
- free_validation_state_cb (void *cls,
- const struct GNUNET_PeerIdentity *pid,
- void *value)
- {
- struct ValidationState *vs = value;
- (void) cls;
- (void) pid;
- free_validation_state (vs);
- return GNUNET_OK;
- }
- /**
- * Free pending acknowledgement.
- *
- * @param cls NULL
- * @param key unused
- * @param value a `struct PendingAcknowledgement`
- * @return #GNUNET_OK (always)
- */
- static int
- free_pending_ack_cb (void *cls, const struct GNUNET_Uuid *key, void *value)
- {
- struct PendingAcknowledgement *pa = value;
- (void) cls;
- (void) key;
- free_pending_acknowledgement (pa);
- return GNUNET_OK;
- }
- /**
- * Free acknowledgement cummulator.
- *
- * @param cls NULL
- * @param pid unused
- * @param value a `struct AcknowledgementCummulator`
- * @return #GNUNET_OK (always)
- */
- static int
- free_ack_cummulator_cb (void *cls,
- const struct GNUNET_PeerIdentity *pid,
- void *value)
- {
- struct AcknowledgementCummulator *ac = value;
- (void) cls;
- (void) pid;
- GNUNET_free (ac);
- return GNUNET_OK;
- }
- /**
- * Function called when the service shuts down. Unloads our plugins
- * and cancels pending validations.
- *
- * @param cls closure, unused
- */
- static void
- do_shutdown (void *cls)
- {
- struct LearnLaunchEntry *lle;
- (void) cls;
- GNUNET_CONTAINER_multipeermap_iterate (neighbours, &free_neighbour_cb, NULL);
- if (NULL != peerstore)
- {
- GNUNET_PEERSTORE_disconnect (peerstore, GNUNET_NO);
- peerstore = NULL;
- }
- if (NULL != GST_stats)
- {
- GNUNET_STATISTICS_destroy (GST_stats, GNUNET_NO);
- GST_stats = NULL;
- }
- if (NULL != GST_my_private_key)
- {
- GNUNET_free (GST_my_private_key);
- GST_my_private_key = NULL;
- }
- GNUNET_CONTAINER_multipeermap_iterate (ack_cummulators,
- &free_ack_cummulator_cb,
- NULL);
- GNUNET_CONTAINER_multipeermap_destroy (ack_cummulators);
- ack_cummulators = NULL;
- GNUNET_CONTAINER_multiuuidmap_iterate (pending_acks,
- &free_pending_ack_cb,
- NULL);
- GNUNET_CONTAINER_multiuuidmap_destroy (pending_acks);
- pending_acks = NULL;
- GNUNET_break (0 == GNUNET_CONTAINER_multipeermap_size (neighbours));
- GNUNET_CONTAINER_multipeermap_destroy (neighbours);
- neighbours = NULL;
- GNUNET_break (0 == GNUNET_CONTAINER_multipeermap_size (links));
- GNUNET_CONTAINER_multipeermap_destroy (links);
- links = NULL;
- GNUNET_CONTAINER_multipeermap_iterate (backtalkers,
- &free_backtalker_cb,
- NULL);
- GNUNET_CONTAINER_multipeermap_destroy (backtalkers);
- backtalkers = NULL;
- GNUNET_CONTAINER_multipeermap_iterate (validation_map,
- &free_validation_state_cb,
- NULL);
- GNUNET_CONTAINER_multipeermap_destroy (validation_map);
- validation_map = NULL;
- while (NULL != ir_head)
- free_incoming_request (ir_head);
- GNUNET_assert (0 == ir_total);
- while (NULL != (lle = lle_head))
- {
- GNUNET_CONTAINER_DLL_remove (lle_head, lle_tail, lle);
- GNUNET_free (lle);
- }
- GNUNET_CONTAINER_multishortmap_destroy (dvlearn_map);
- dvlearn_map = NULL;
- GNUNET_CONTAINER_heap_destroy (validation_heap);
- validation_heap = NULL;
- GNUNET_CONTAINER_multipeermap_iterate (dv_routes, &free_dv_routes_cb, NULL);
- GNUNET_CONTAINER_multipeermap_destroy (dv_routes);
- dv_routes = NULL;
- }
- /**
- * Initiate transport service.
- *
- * @param cls closure
- * @param c configuration to use
- * @param service the initialized service
- */
- static void
- run (void *cls,
- const struct GNUNET_CONFIGURATION_Handle *c,
- struct GNUNET_SERVICE_Handle *service)
- {
- (void) cls;
- (void) service;
- /* setup globals */
- hello_mono_time = GNUNET_TIME_absolute_get_monotonic (c);
- GST_cfg = c;
- backtalkers = GNUNET_CONTAINER_multipeermap_create (16, GNUNET_YES);
- pending_acks = GNUNET_CONTAINER_multiuuidmap_create (32768, GNUNET_YES);
- ack_cummulators = GNUNET_CONTAINER_multipeermap_create (256, GNUNET_YES);
- neighbours = GNUNET_CONTAINER_multipeermap_create (1024, GNUNET_YES);
- links = GNUNET_CONTAINER_multipeermap_create (512, GNUNET_YES);
- dv_routes = GNUNET_CONTAINER_multipeermap_create (1024, GNUNET_YES);
- dvlearn_map = GNUNET_CONTAINER_multishortmap_create (2 * MAX_DV_LEARN_PENDING,
- GNUNET_YES);
- validation_map = GNUNET_CONTAINER_multipeermap_create (1024, GNUNET_YES);
- validation_heap =
- GNUNET_CONTAINER_heap_create (GNUNET_CONTAINER_HEAP_ORDER_MIN);
- GST_my_private_key =
- GNUNET_CRYPTO_eddsa_key_create_from_configuration (GST_cfg);
- if (NULL == GST_my_private_key)
- {
- GNUNET_log (
- GNUNET_ERROR_TYPE_ERROR,
- _ (
- "Transport service is lacking key configuration settings. Exiting.\n"));
- GNUNET_SCHEDULER_shutdown ();
- return;
- }
- GNUNET_CRYPTO_eddsa_key_get_public (GST_my_private_key,
- &GST_my_identity.public_key);
- GNUNET_log (GNUNET_ERROR_TYPE_INFO,
- "My identity is `%s'\n",
- GNUNET_i2s_full (&GST_my_identity));
- GST_stats = GNUNET_STATISTICS_create ("transport", GST_cfg);
- GNUNET_SCHEDULER_add_shutdown (&do_shutdown, NULL);
- peerstore = GNUNET_PEERSTORE_connect (GST_cfg);
- if (NULL == peerstore)
- {
- GNUNET_break (0);
- GNUNET_SCHEDULER_shutdown ();
- return;
- }
- }
- /**
- * Define "main" method using service macro.
- */
- GNUNET_SERVICE_MAIN (
- "transport",
- GNUNET_SERVICE_OPTION_SOFT_SHUTDOWN,
- &run,
- &client_connect_cb,
- &client_disconnect_cb,
- NULL,
- /* communication with applications */
- GNUNET_MQ_hd_fixed_size (suggest,
- GNUNET_MESSAGE_TYPE_TRANSPORT_SUGGEST,
- struct ExpressPreferenceMessage,
- NULL),
- GNUNET_MQ_hd_fixed_size (suggest_cancel,
- GNUNET_MESSAGE_TYPE_TRANSPORT_SUGGEST_CANCEL,
- struct ExpressPreferenceMessage,
- NULL),
- GNUNET_MQ_hd_var_size (request_hello_validation,
- GNUNET_MESSAGE_TYPE_TRANSPORT_REQUEST_HELLO_VALIDATION,
- struct RequestHelloValidationMessage,
- NULL),
- /* communication with core */
- GNUNET_MQ_hd_fixed_size (client_start,
- GNUNET_MESSAGE_TYPE_TRANSPORT_START,
- struct StartMessage,
- NULL),
- GNUNET_MQ_hd_var_size (client_send,
- GNUNET_MESSAGE_TYPE_TRANSPORT_SEND,
- struct OutboundMessage,
- NULL),
- GNUNET_MQ_hd_fixed_size (client_recv_ok,
- GNUNET_MESSAGE_TYPE_TRANSPORT_RECV_OK,
- struct RecvOkMessage,
- NULL),
- /* communication with communicators */
- GNUNET_MQ_hd_var_size (communicator_available,
- GNUNET_MESSAGE_TYPE_TRANSPORT_NEW_COMMUNICATOR,
- struct GNUNET_TRANSPORT_CommunicatorAvailableMessage,
- NULL),
- GNUNET_MQ_hd_var_size (communicator_backchannel,
- GNUNET_MESSAGE_TYPE_TRANSPORT_COMMUNICATOR_BACKCHANNEL,
- struct GNUNET_TRANSPORT_CommunicatorBackchannel,
- NULL),
- GNUNET_MQ_hd_var_size (add_address,
- GNUNET_MESSAGE_TYPE_TRANSPORT_ADD_ADDRESS,
- struct GNUNET_TRANSPORT_AddAddressMessage,
- NULL),
- GNUNET_MQ_hd_fixed_size (del_address,
- GNUNET_MESSAGE_TYPE_TRANSPORT_DEL_ADDRESS,
- struct GNUNET_TRANSPORT_DelAddressMessage,
- NULL),
- GNUNET_MQ_hd_var_size (incoming_msg,
- GNUNET_MESSAGE_TYPE_TRANSPORT_INCOMING_MSG,
- struct GNUNET_TRANSPORT_IncomingMessage,
- NULL),
- GNUNET_MQ_hd_fixed_size (queue_create_ok,
- GNUNET_MESSAGE_TYPE_TRANSPORT_QUEUE_CREATE_OK,
- struct GNUNET_TRANSPORT_CreateQueueResponse,
- NULL),
- GNUNET_MQ_hd_fixed_size (queue_create_fail,
- GNUNET_MESSAGE_TYPE_TRANSPORT_QUEUE_CREATE_FAIL,
- struct GNUNET_TRANSPORT_CreateQueueResponse,
- NULL),
- GNUNET_MQ_hd_var_size (add_queue_message,
- GNUNET_MESSAGE_TYPE_TRANSPORT_QUEUE_SETUP,
- struct GNUNET_TRANSPORT_AddQueueMessage,
- NULL),
- GNUNET_MQ_hd_fixed_size (del_queue_message,
- GNUNET_MESSAGE_TYPE_TRANSPORT_QUEUE_TEARDOWN,
- struct GNUNET_TRANSPORT_DelQueueMessage,
- NULL),
- GNUNET_MQ_hd_fixed_size (send_message_ack,
- GNUNET_MESSAGE_TYPE_TRANSPORT_SEND_MSG_ACK,
- struct GNUNET_TRANSPORT_SendMessageToAck,
- NULL),
- /* communication with monitors */
- GNUNET_MQ_hd_fixed_size (monitor_start,
- GNUNET_MESSAGE_TYPE_TRANSPORT_MONITOR_START,
- struct GNUNET_TRANSPORT_MonitorStart,
- NULL),
- GNUNET_MQ_handler_end ());
- /* end of file gnunet-service-transport.c */
|