dns.h 12 KB

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  1. #include <thread.h> /* for Ref */
  2. typedef struct Ndbtuple Ndbtuple;
  3. enum
  4. {
  5. /* RR types; see: http://www.iana.org/assignments/dns-parameters */
  6. Ta= 1,
  7. Tns= 2,
  8. Tmd= 3,
  9. Tmf= 4,
  10. Tcname= 5,
  11. Tsoa= 6,
  12. Tmb= 7,
  13. Tmg= 8,
  14. Tmr= 9,
  15. Tnull= 10,
  16. Twks= 11,
  17. Tptr= 12,
  18. Thinfo= 13,
  19. Tminfo= 14,
  20. Tmx= 15,
  21. Ttxt= 16,
  22. Trp= 17,
  23. Tafsdb= 18,
  24. Tx25= 19,
  25. Tisdn= 20,
  26. Trt= 21,
  27. Tnsap= 22,
  28. Tnsapptr= 23,
  29. Tsig= 24,
  30. Tkey= 25,
  31. Tpx= 26,
  32. Tgpos= 27,
  33. Taaaa= 28,
  34. Tloc= 29,
  35. Tnxt= 30,
  36. Teid= 31,
  37. Tnimloc= 32,
  38. Tsrv= 33,
  39. Tatma= 34,
  40. Tnaptr= 35,
  41. Tkx= 36,
  42. Tcert= 37,
  43. Ta6= 38,
  44. Tdname= 39,
  45. Tsink= 40,
  46. Topt= 41,
  47. Tapl= 42,
  48. Tds= 43,
  49. Tsshfp= 44,
  50. Tipseckey= 45,
  51. Trrsig= 46,
  52. Tnsec= 47,
  53. Tdnskey= 48,
  54. Tspf= 99,
  55. Tuinfo= 100,
  56. Tuid= 101,
  57. Tgid= 102,
  58. Tunspec= 103,
  59. /* query types (all RR types are also queries) */
  60. Ttkey= 249, /* transaction key */
  61. Ttsig= 250, /* transaction signature */
  62. Tixfr= 251, /* incremental zone transfer */
  63. Taxfr= 252, /* zone transfer */
  64. Tmailb= 253, /* { Tmb, Tmg, Tmr } */
  65. Tmaila= 254, /* obsolete */
  66. Tall= 255, /* all records */
  67. /* classes */
  68. Csym= 0, /* internal symbols */
  69. Cin= 1, /* internet */
  70. Ccs, /* CSNET (obsolete) */
  71. Cch, /* Chaos net */
  72. Chs, /* Hesiod (?) */
  73. /* class queries (all class types are also queries) */
  74. Call= 255, /* all classes */
  75. /* opcodes */
  76. Oquery= 0<<11, /* normal query */
  77. Oinverse= 1<<11, /* inverse query (retired) */
  78. Ostatus= 2<<11, /* status request */
  79. Onotify= 4<<11, /* notify slaves of updates */
  80. Oupdate= 5<<11,
  81. Omask= 0xf<<11, /* mask for opcode */
  82. /* response codes */
  83. Rok= 0,
  84. Rformat= 1, /* format error */
  85. Rserver= 2, /* server failure (e.g. no answer from something) */
  86. Rname= 3, /* bad name */
  87. Runimplimented= 4, /* unimplemented */
  88. Rrefused= 5, /* we don't like you */
  89. Ryxdomain= 6, /* name exists when it should not */
  90. Ryxrrset= 7, /* rr set exists when it should not */
  91. Rnxrrset= 8, /* rr set that should exist does not */
  92. Rnotauth= 9, /* not authoritative */
  93. Rnotzone= 10, /* name not in zone */
  94. Rbadvers= 16, /* bad opt version */
  95. /* Rbadsig= 16, */ /* also tsig signature failure */
  96. Rbadkey= 17, /* key not recognized */
  97. Rbadtime= 18, /* signature out of time window */
  98. Rbadmode= 19, /* bad tkey mode */
  99. Rbadname= 20, /* duplicate key name */
  100. Rbadalg= 21, /* algorithm not supported */
  101. Rmask= 0x1f, /* mask for response */
  102. Rtimeout= 1<<5, /* timeout sending (for internal use only) */
  103. /* bits in flag word (other than opcode and response) */
  104. Fresp= 1<<15, /* message is a response */
  105. Fauth= 1<<10, /* true if an authoritative response */
  106. Ftrunc= 1<<9, /* truncated message */
  107. Frecurse= 1<<8, /* request recursion */
  108. Fcanrec= 1<<7, /* server can recurse */
  109. Domlen= 256, /* max domain name length (with NULL) */
  110. Labellen= 64, /* max domain label length (with NULL) */
  111. Strlen= 256, /* max string length (with NULL) */
  112. /* time to live values (in seconds) */
  113. Min= 60,
  114. Hour= 60*Min, /* */
  115. Day= 24*Hour, /* Ta, Tmx */
  116. Week= 7*Day, /* Tsoa, Tns */
  117. Year= 52*Week,
  118. DEFTTL= Day,
  119. /* reserved time (can't be timed out earlier) */
  120. Reserved= 5*Min,
  121. /* packet sizes */
  122. Maxudp= 512, /* maximum bytes per udp message */
  123. Maxudpin= 2048, /* maximum bytes per udp message */
  124. /* length of domain name hash table */
  125. HTLEN= 4*1024,
  126. Maxpath= 128, /* size of mntpt */
  127. Maxlcks= 10, /* max. query-type locks per domain name */
  128. RRmagic= 0xdeadbabe,
  129. DNmagic= 0xa110a110,
  130. /* parallelism: tune; was 32; allow lots */
  131. Maxactive= 250,
  132. /* tune; was 60; keep it short */
  133. Maxreqtm= 10, /* max. seconds to process a request */
  134. Notauthoritative = 0,
  135. Authoritative,
  136. };
  137. typedef struct Area Area;
  138. typedef struct Block Block;
  139. typedef struct Cert Cert;
  140. typedef struct DN DN;
  141. typedef struct DNSmsg DNSmsg;
  142. typedef struct Key Key;
  143. typedef struct Null Null;
  144. typedef struct RR RR;
  145. typedef struct Request Request;
  146. typedef struct SOA SOA;
  147. typedef struct Server Server;
  148. typedef struct Sig Sig;
  149. typedef struct Srv Srv;
  150. typedef struct Txt Txt;
  151. /*
  152. * a structure to track a request and any slave process handling it
  153. */
  154. struct Request
  155. {
  156. int isslave; /* pid of slave */
  157. ulong aborttime; /* time at which we give up */
  158. jmp_buf mret; /* where master jumps to after starting a slave */
  159. int id;
  160. char *from; /* who asked us? */
  161. };
  162. typedef struct Querylck Querylck;
  163. struct Querylck
  164. {
  165. QLock;
  166. // Rendez;
  167. Ref;
  168. };
  169. /*
  170. * a domain name
  171. */
  172. struct DN
  173. {
  174. DN *next; /* hash collision list */
  175. ulong magic;
  176. char *name; /* owner */
  177. RR *rr; /* resource records off this name */
  178. ulong referenced; /* time last referenced */
  179. ulong lookuptime; /* last time we tried to get a better value */
  180. /* refs was `char' but we've seen refs > 120, so go whole hog */
  181. ulong refs; /* for mark and sweep */
  182. ulong ordinal;
  183. ushort class; /* RR class */
  184. uchar keep; /* flag: never age this name */
  185. uchar respcode; /* response code */
  186. /* was: char nonexistent; /* true if we get an authoritative nx for this domain */
  187. /* permit only 1 query per (domain name, type) at a time */
  188. Querylck querylck[Maxlcks];
  189. };
  190. /*
  191. * security info
  192. */
  193. struct Block
  194. {
  195. int dlen;
  196. uchar *data;
  197. };
  198. struct Key
  199. {
  200. int flags;
  201. int proto;
  202. int alg;
  203. Block;
  204. };
  205. struct Cert
  206. {
  207. int type;
  208. int tag;
  209. int alg;
  210. Block;
  211. };
  212. struct Sig
  213. {
  214. Cert;
  215. int labels;
  216. ulong ttl;
  217. ulong exp;
  218. ulong incep;
  219. DN *signer;
  220. };
  221. struct Null
  222. {
  223. Block;
  224. };
  225. /*
  226. * text strings
  227. */
  228. struct Txt
  229. {
  230. Txt *next;
  231. char *p;
  232. };
  233. /*
  234. * an unpacked resource record
  235. */
  236. struct RR
  237. {
  238. RR *next;
  239. ulong magic;
  240. DN *owner; /* domain that owns this resource record */
  241. uintptr pc; /* for tracking memory allocation */
  242. ulong ttl; /* time to live to be passed on */
  243. ulong expire; /* time this entry expires locally */
  244. ulong marker; /* used locally when scanning rrlists */
  245. ushort type; /* RR type */
  246. ushort query; /* query type is in response to */
  247. uchar auth; /* flag: authoritative */
  248. uchar db; /* flag: from database */
  249. uchar cached; /* flag: rr in cache */
  250. uchar negative; /* flag: this is a cached negative response */
  251. union { /* discriminated by negative & type */
  252. DN *negsoaowner; /* soa for cached negative response */
  253. DN *host; /* hostname - soa, cname, mb, md, mf, mx, ns, srv */
  254. DN *cpu; /* cpu type - hinfo */
  255. DN *mb; /* mailbox - mg, minfo */
  256. DN *ip; /* ip address - a, aaaa */
  257. DN *rp; /* rp arg - rp */
  258. uintptr arg0; /* arg[01] are compared to find dups in dn.c */
  259. };
  260. union { /* discriminated by negative & type */
  261. int negrcode; /* response code for cached negative resp. */
  262. DN *rmb; /* responsible maibox - minfo, soa, rp */
  263. DN *ptr; /* pointer to domain name - ptr */
  264. DN *os; /* operating system - hinfo */
  265. ulong pref; /* preference value - mx */
  266. ulong local; /* ns served from local database - ns */
  267. ushort port; /* - srv */
  268. uintptr arg1; /* arg[01] are compared to find dups in dn.c */
  269. };
  270. union { /* discriminated by type */
  271. SOA *soa; /* soa timers - soa */
  272. Key *key;
  273. Cert *cert;
  274. Sig *sig;
  275. Null *null;
  276. Txt *txt;
  277. Srv *srv;
  278. };
  279. };
  280. /*
  281. * list of servers
  282. */
  283. struct Server
  284. {
  285. Server *next;
  286. char *name;
  287. };
  288. /*
  289. * timers for a start-of-authority record. all ulongs are in seconds.
  290. */
  291. struct SOA
  292. {
  293. ulong serial; /* zone serial # */
  294. ulong refresh; /* zone refresh interval */
  295. ulong retry; /* zone retry interval */
  296. ulong expire; /* time to expiration */
  297. ulong minttl; /* min. time to live for any entry */
  298. Server *slaves; /* slave servers */
  299. };
  300. /*
  301. * srv (service location) record (rfc2782):
  302. * _service._proto.name ttl class(IN) 'SRV' priority weight port target
  303. */
  304. struct Srv
  305. {
  306. ushort pri;
  307. ushort weight;
  308. };
  309. struct Rrlist
  310. {
  311. int count;
  312. RR *rrs;
  313. };
  314. /*
  315. * domain messages
  316. */
  317. struct DNSmsg
  318. {
  319. ushort id;
  320. int flags;
  321. int qdcount; /* questions */
  322. RR *qd;
  323. int ancount; /* answers */
  324. RR *an;
  325. int nscount; /* name servers */
  326. RR *ns;
  327. int arcount; /* hints */
  328. RR *ar;
  329. };
  330. /*
  331. * definition of local area for dblookup
  332. */
  333. struct Area
  334. {
  335. Area *next;
  336. int len; /* strlen(area->soarr->owner->name) */
  337. RR *soarr; /* soa defining this area */
  338. int neednotify;
  339. int needrefresh;
  340. };
  341. typedef struct Cfg Cfg;
  342. struct Cfg {
  343. int cachedb;
  344. int resolver;
  345. int justforw; /* flag: pure resolver, just forward queries */
  346. int serve; /* flag: serve udp queries */
  347. int inside;
  348. int straddle;
  349. };
  350. /* (udp) query stats */
  351. typedef struct {
  352. QLock;
  353. ulong slavehiwat; /* procs */
  354. ulong qrecvd9p; /* query counts */
  355. ulong qrecvdudp;
  356. ulong qsent;
  357. ulong qrecvd9prpc; /* packet count */
  358. ulong alarms;
  359. /* reply times by count */
  360. ulong under10ths[3*10+2]; /* under n*0.1 seconds, n is index */
  361. ulong tmout;
  362. ulong tmoutcname;
  363. ulong tmoutv6;
  364. ulong answinmem; /* answers in memory */
  365. ulong negans; /* negative answers received */
  366. ulong negserver; /* neg ans with Rserver set */
  367. ulong negbaddeleg; /* neg ans with bad delegations */
  368. ulong negbdnoans; /* ⋯ and no answers */
  369. ulong negnorname; /* neg ans with no Rname set */
  370. ulong negcached; /* neg ans cached */
  371. } Stats;
  372. Stats stats;
  373. enum
  374. {
  375. Recurse,
  376. Dontrecurse,
  377. NOneg,
  378. OKneg,
  379. };
  380. extern Cfg cfg;
  381. extern char *dbfile;
  382. extern int debug;
  383. extern Area *delegated;
  384. extern char *logfile;
  385. extern int maxage; /* age of oldest entry in cache (secs) */
  386. extern char mntpt[];
  387. extern int needrefresh;
  388. extern int norecursion;
  389. extern ulong now; /* time base */
  390. extern vlong nowns;
  391. extern Area *owned;
  392. extern int sendnotifies;
  393. extern ulong target;
  394. extern int testing; /* test cache whenever removing a DN */
  395. extern char *trace;
  396. extern int traceactivity;
  397. extern char *zonerefreshprogram;
  398. #pragma varargck type "R" RR*
  399. #pragma varargck type "Q" RR*
  400. /* dn.c */
  401. extern char *rrtname[];
  402. extern char *rname[];
  403. extern unsigned nrname;
  404. extern char *opname[];
  405. void abort(); /* char*, ... */;
  406. void addserver(Server**, char*);
  407. Server* copyserverlist(Server*);
  408. void db2cache(int);
  409. void dnage(DN*);
  410. void dnageall(int);
  411. void dnagedb(void);
  412. void dnagenever(void);
  413. void dnauthdb(void);
  414. void dncheck(void*, int);
  415. void dndump(char*);
  416. void dnget(void);
  417. void dninit(void);
  418. DN* dnlookup(char*, int, int);
  419. void dnptr(uchar*, uchar*, char*, int, int, int);
  420. void dnpurge(void);
  421. void dnput(void);
  422. void dnslog(char*, ...);
  423. void dnstats(char *file);
  424. void* emalloc(int);
  425. char* estrdup(char*);
  426. void freeanswers(DNSmsg *mp);
  427. void freeserverlist(Server*);
  428. int getactivity(Request*, int);
  429. Area* inmyarea(char*);
  430. void putactivity(int);
  431. RR* randomize(RR*);
  432. RR* rralloc(int);
  433. void rrattach(RR*, int);
  434. int rravfmt(Fmt*);
  435. RR* rrcat(RR**, RR*);
  436. RR** rrcopy(RR*, RR**);
  437. int rrfmt(Fmt*);
  438. void rrfree(RR*);
  439. void rrfreelist(RR*);
  440. RR* rrlookup(DN*, int, int);
  441. char* rrname(int, char*, int);
  442. RR* rrremneg(RR**);
  443. RR* rrremtype(RR**, int);
  444. int rrsupported(int);
  445. int rrtype(char*);
  446. void slave(Request*);
  447. int subsume(char*, char*);
  448. int tsame(int, int);
  449. void unique(RR*);
  450. void warning(char*, ...);
  451. /* dnarea.c */
  452. void refresh_areas(Area*);
  453. void freearea(Area**);
  454. void addarea(DN *dp, RR *rp, Ndbtuple *t);
  455. /* dblookup.c */
  456. int baddelegation(RR*, RR*, uchar*);
  457. RR* dbinaddr(DN*, int);
  458. RR* dblookup(char*, int, int, int, int);
  459. void dnforceage(void);
  460. RR* dnsservers(int);
  461. RR* domainlist(int);
  462. int insideaddr(char *dom);
  463. int insidens(uchar *ip);
  464. int myaddr(char *addr);
  465. int opendatabase(void);
  466. uchar* outsidens(int);
  467. /* dns.c */
  468. char* walkup(char*);
  469. RR* getdnsservers(int);
  470. void logreply(int, uchar*, DNSmsg*);
  471. void logsend(int, int, uchar*, char*, char*, int);
  472. void procsetname(char *fmt, ...);
  473. /* dnresolve.c */
  474. RR* dnresolve(char*, int, int, Request*, RR**, int, int, int, int*);
  475. int udpport(char *);
  476. int mkreq(DN *dp, int type, uchar *buf, int flags, ushort reqno);
  477. int seerootns(void);
  478. /* dnserver.c */
  479. void dnserver(DNSmsg*, DNSmsg*, Request*, uchar *, int);
  480. void dnudpserver(char*);
  481. void dntcpserver(char*);
  482. /* dnnotify.c */
  483. void dnnotify(DNSmsg*, DNSmsg*, Request*);
  484. void notifyproc(void);
  485. /* convDNS2M.c */
  486. int convDNS2M(DNSmsg*, uchar*, int);
  487. /* convM2DNS.c */
  488. char* convM2DNS(uchar*, int, DNSmsg*, int*);
  489. #pragma varargck argpos dnslog 1