ip.h 15 KB

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  1. typedef struct Conv Conv;
  2. typedef struct Fs Fs;
  3. typedef union Hwaddr Hwaddr;
  4. typedef struct Ifcconv Ifcconv;
  5. typedef struct IP IP;
  6. typedef struct IPaux IPaux;
  7. typedef struct Ipself Ipself;
  8. typedef struct Ipselftab Ipselftab;
  9. typedef struct Iplink Iplink;
  10. typedef struct Iplifc Iplifc;
  11. typedef struct Ipmulti Ipmulti;
  12. typedef struct Ipmux Ipmux;
  13. typedef struct IProuter IProuter;
  14. typedef struct Ipifc Ipifc;
  15. typedef struct Iphash Iphash;
  16. typedef struct Ipht Ipht;
  17. typedef struct Netlog Netlog;
  18. typedef struct Ifclog Ifclog;
  19. typedef struct Medium Medium;
  20. typedef struct Proto Proto;
  21. typedef struct Pstate Pstate;
  22. typedef struct Tcpc Tcpc;
  23. typedef struct Arpent Arpent;
  24. typedef struct Arp Arp;
  25. typedef struct Route Route;
  26. typedef struct Routerparams Routerparams;
  27. typedef struct Hostparams Hostparams;
  28. typedef struct v6router v6router;
  29. typedef struct v6params v6params;
  30. enum
  31. {
  32. Addrlen= 64,
  33. Maxproto= 20,
  34. Nhash= 64,
  35. Maxincall= 5,
  36. Nchans= 512,
  37. MAClen= 16, /* longest mac address */
  38. MAXTTL= 255,
  39. DFLTTOS= 0,
  40. IPaddrlen= 16,
  41. IPv4addrlen= 4,
  42. IPv4off= 12,
  43. IPllen= 4,
  44. /* ip versions */
  45. V4= 4,
  46. V6= 6,
  47. IP_VER4= 0x40,
  48. IP_VER6= 0x60,
  49. /* 2^Lroot trees in the root table */
  50. Lroot= 10,
  51. Maxpath = 64,
  52. };
  53. enum
  54. {
  55. Idle= 0,
  56. Announcing= 1,
  57. Announced= 2,
  58. Connecting= 3,
  59. Connected= 4,
  60. };
  61. /*
  62. * one per conversation directory
  63. */
  64. struct Conv
  65. {
  66. QLock;
  67. int x; /* conversation index */
  68. Proto* p;
  69. int restricted; /* remote port is restricted */
  70. uint ttl; /* max time to live */
  71. uint tos; /* type of service */
  72. int ignoreadvice; /* don't terminate connection on icmp errors */
  73. uchar ipversion;
  74. uchar laddr[IPaddrlen]; /* local IP address */
  75. uchar raddr[IPaddrlen]; /* remote IP address */
  76. ushort lport; /* local port number */
  77. ushort rport; /* remote port number */
  78. char *owner; /* protections */
  79. int perm;
  80. int inuse; /* opens of listen/data/ctl */
  81. int length;
  82. int state;
  83. /* udp specific */
  84. int headers; /* data src/dst headers in udp */
  85. int reliable; /* true if reliable udp */
  86. Conv* incall; /* calls waiting to be listened for */
  87. Conv* next;
  88. Queue* rq; /* queued data waiting to be read */
  89. Queue* wq; /* queued data waiting to be written */
  90. Queue* eq; /* returned error packets */
  91. Queue* sq; /* snooping queue */
  92. Ref snoopers; /* number of processes with snoop open */
  93. QLock car;
  94. Rendez cr;
  95. char cerr[ERRMAX];
  96. QLock listenq;
  97. Rendez listenr;
  98. Ipmulti *multi; /* multicast bindings for this interface */
  99. void* ptcl; /* protocol specific stuff */
  100. };
  101. struct Medium
  102. {
  103. char *name;
  104. int hsize; /* medium header size */
  105. int mintu; /* default min mtu */
  106. int maxtu; /* default max mtu */
  107. int maclen; /* mac address length */
  108. void (*bind)(Ipifc*, int, char**);
  109. void (*unbind)(Ipifc*);
  110. void (*bwrite)(Ipifc *ifc, Block *b, int version, uchar *ip);
  111. /* for arming interfaces to receive multicast */
  112. void (*addmulti)(Ipifc *ifc, uchar *a, uchar *ia);
  113. void (*remmulti)(Ipifc *ifc, uchar *a, uchar *ia);
  114. /* process packets written to 'data' */
  115. void (*pktin)(Fs *f, Ipifc *ifc, Block *bp);
  116. /* routes for router boards */
  117. void (*addroute)(Ipifc *ifc, int, uchar*, uchar*, uchar*, int);
  118. void (*remroute)(Ipifc *ifc, int, uchar*, uchar*);
  119. void (*flushroutes)(Ipifc *ifc);
  120. /* for routing multicast groups */
  121. void (*joinmulti)(Ipifc *ifc, uchar *a, uchar *ia);
  122. void (*leavemulti)(Ipifc *ifc, uchar *a, uchar *ia);
  123. /* address resolution */
  124. void (*ares)(Fs*, int, uchar*, uchar*, int, int); /* resolve */
  125. void (*areg)(Ipifc*, uchar*); /* register */
  126. /* v6 address generation */
  127. void (*pref2addr)(uchar *pref, uchar *ea);
  128. int unbindonclose; /* if non-zero, unbind on last close */
  129. };
  130. /* logical interface associated with a physical one */
  131. struct Iplifc
  132. {
  133. uchar local[IPaddrlen];
  134. uchar mask[IPaddrlen];
  135. uchar remote[IPaddrlen];
  136. uchar net[IPaddrlen];
  137. uchar tentative; /* =1 => v6 dup disc on, =0 => confirmed unique */
  138. uchar onlink; /* =1 => onlink, =0 offlink. */
  139. uchar autoflag; /* v6 autonomous flag */
  140. long validlt; /* v6 valid lifetime */
  141. long preflt; /* v6 preferred lifetime */
  142. long origint; /* time when addr was added */
  143. Iplink *link; /* addresses linked to this lifc */
  144. Iplifc *next;
  145. };
  146. /* binding twixt Ipself and Iplifc */
  147. struct Iplink
  148. {
  149. Ipself *self;
  150. Iplifc *lifc;
  151. Iplink *selflink; /* next link for this local address */
  152. Iplink *lifclink; /* next link for this ifc */
  153. ulong expire;
  154. Iplink *next; /* free list */
  155. int ref;
  156. };
  157. /* rfc 2461, pp.40--43. */
  158. /* default values, one per stack */
  159. struct Routerparams {
  160. int mflag;
  161. int oflag;
  162. int maxraint;
  163. int minraint;
  164. int linkmtu;
  165. int reachtime;
  166. int rxmitra;
  167. int ttl;
  168. int routerlt;
  169. };
  170. struct Hostparams {
  171. int rxmithost;
  172. };
  173. struct Ipifc
  174. {
  175. RWlock;
  176. Conv *conv; /* link to its conversation structure */
  177. char dev[64]; /* device we're attached to */
  178. Medium *m; /* Media pointer */
  179. int maxtu; /* Maximum transfer unit */
  180. int mintu; /* Minumum tranfer unit */
  181. int mbps; /* megabits per second */
  182. void *arg; /* medium specific */
  183. int reassemble; /* reassemble IP packets before forwarding */
  184. /* these are used so that we can unbind on the fly */
  185. Lock idlock;
  186. uchar ifcid; /* incremented each 'bind/unbind/add/remove' */
  187. int ref; /* number of proc's using this ipifc */
  188. Rendez wait; /* where unbinder waits for ref == 0 */
  189. int unbinding;
  190. uchar mac[MAClen]; /* MAC address */
  191. Iplifc *lifc; /* logical interfaces on this physical one */
  192. ulong in, out; /* message statistics */
  193. ulong inerr, outerr; /* ... */
  194. uchar sendra6; /* == 1 => send router advs on this ifc */
  195. uchar recvra6; /* == 1 => recv router advs on this ifc */
  196. Routerparams rp; /* router parameters as in RFC 2461, pp.40--43.
  197. used only if node is router */
  198. };
  199. /*
  200. * one per multicast-lifc pair used by a Conv
  201. */
  202. struct Ipmulti
  203. {
  204. uchar ma[IPaddrlen];
  205. uchar ia[IPaddrlen];
  206. Ipmulti *next;
  207. };
  208. /*
  209. * hash table for 2 ip addresses + 2 ports
  210. */
  211. enum
  212. {
  213. Nipht= 521, /* convenient prime */
  214. IPmatchexact= 0, /* match on 4 tuple */
  215. IPmatchany, /* *!* */
  216. IPmatchport, /* *!port */
  217. IPmatchaddr, /* addr!* */
  218. IPmatchpa, /* addr!port */
  219. };
  220. struct Iphash
  221. {
  222. Iphash *next;
  223. Conv *c;
  224. int match;
  225. };
  226. struct Ipht
  227. {
  228. Lock;
  229. Iphash *tab[Nipht];
  230. };
  231. void iphtadd(Ipht*, Conv*);
  232. void iphtrem(Ipht*, Conv*);
  233. Conv* iphtlook(Ipht *ht, uchar *sa, ushort sp, uchar *da, ushort dp);
  234. /*
  235. * one per multiplexed protocol
  236. */
  237. struct Proto
  238. {
  239. QLock;
  240. char* name; /* protocol name */
  241. int x; /* protocol index */
  242. int ipproto; /* ip protocol type */
  243. char* (*connect)(Conv*, char**, int);
  244. char* (*announce)(Conv*, char**, int);
  245. char* (*bind)(Conv*, char**, int);
  246. int (*state)(Conv*, char*, int);
  247. void (*create)(Conv*);
  248. void (*close)(Conv*);
  249. void (*rcv)(Proto*, Ipifc*, Block*);
  250. char* (*ctl)(Conv*, char**, int);
  251. void (*advise)(Proto*, Block*, char*);
  252. int (*stats)(Proto*, char*, int);
  253. int (*local)(Conv*, char*, int);
  254. int (*remote)(Conv*, char*, int);
  255. int (*inuse)(Conv*);
  256. int (*gc)(Proto*); /* returns true if any conversations are freed */
  257. Fs *f; /* file system this proto is part of */
  258. Conv **conv; /* array of conversations */
  259. int ptclsize; /* size of per protocol ctl block */
  260. int nc; /* number of conversations */
  261. int ac;
  262. Qid qid; /* qid for protocol directory */
  263. ushort nextport;
  264. ushort nextrport;
  265. void *priv;
  266. };
  267. /*
  268. * one per IP protocol stack
  269. */
  270. struct Fs
  271. {
  272. RWlock;
  273. int dev;
  274. int np;
  275. Proto* p[Maxproto+1]; /* list of supported protocols */
  276. Proto* t2p[256]; /* vector of all protocols */
  277. Proto* ipifc; /* kludge for ipifcremroute & ipifcaddroute */
  278. Proto* ipmux; /* kludge for finding an ip multiplexor */
  279. IP *ip;
  280. Ipselftab *self;
  281. Arp *arp;
  282. v6params *v6p;
  283. Route *v4root[1<<Lroot]; /* v4 routing forest */
  284. Route *v6root[1<<Lroot]; /* v6 routing forest */
  285. Route *queue; /* used as temp when reinjecting routes */
  286. Netlog *alog;
  287. Ifclog *ilog;
  288. char ndb[1024]; /* an ndb entry for this interface */
  289. int ndbvers;
  290. long ndbmtime;
  291. };
  292. /* one per default router known to host */
  293. struct v6router {
  294. uchar inuse;
  295. Ipifc *ifc;
  296. int ifcid;
  297. uchar routeraddr[IPaddrlen];
  298. long ltorigin;
  299. Routerparams rp;
  300. };
  301. struct v6params
  302. {
  303. Routerparams rp; /* v6 params, one copy per node now */
  304. Hostparams hp;
  305. v6router v6rlist[3]; /* max 3 default routers, currently */
  306. int cdrouter; /* uses only v6rlist[cdrouter] if */
  307. /* cdrouter >= 0. */
  308. };
  309. int Fsconnected(Conv*, char*);
  310. Conv* Fsnewcall(Conv*, uchar*, ushort, uchar*, ushort, uchar);
  311. int Fspcolstats(char*, int);
  312. int Fsproto(Fs*, Proto*);
  313. int Fsbuiltinproto(Fs*, uchar);
  314. Conv* Fsprotoclone(Proto*, char*);
  315. Proto* Fsrcvpcol(Fs*, uchar);
  316. Proto* Fsrcvpcolx(Fs*, uchar);
  317. char* Fsstdconnect(Conv*, char**, int);
  318. char* Fsstdannounce(Conv*, char**, int);
  319. char* Fsstdbind(Conv*, char**, int);
  320. ulong scalednconv(void);
  321. void closeconv(Conv*);
  322. /*
  323. * logging
  324. */
  325. enum
  326. {
  327. Logip= 1<<1,
  328. Logtcp= 1<<2,
  329. Logfs= 1<<3,
  330. Logil= 1<<4,
  331. Logicmp= 1<<5,
  332. Logudp= 1<<6,
  333. Logcompress= 1<<7,
  334. Logilmsg= 1<<8,
  335. Loggre= 1<<9,
  336. Logppp= 1<<10,
  337. Logtcprxmt= 1<<11,
  338. Logigmp= 1<<12,
  339. Logudpmsg= 1<<13,
  340. Logipmsg= 1<<14,
  341. Logrudp= 1<<15,
  342. Logrudpmsg= 1<<16,
  343. Logesp= 1<<17,
  344. Logtcpwin= 1<<18,
  345. };
  346. void netloginit(Fs*);
  347. void netlogopen(Fs*);
  348. void netlogclose(Fs*);
  349. void netlogctl(Fs*, char*, int);
  350. long netlogread(Fs*, void*, ulong, long);
  351. void netlog(Fs*, int, char*, ...);
  352. void ifcloginit(Fs*);
  353. long ifclogread(Fs*, Chan *,void*, ulong, long);
  354. void ifclog(Fs*, uchar *, int);
  355. void ifclogopen(Fs*, Chan*);
  356. void ifclogclose(Fs*, Chan*);
  357. /*
  358. * iproute.c
  359. */
  360. typedef struct RouteTree RouteTree;
  361. typedef struct Routewalk Routewalk;
  362. typedef struct V4route V4route;
  363. typedef struct V6route V6route;
  364. enum
  365. {
  366. /* type bits */
  367. Rv4= (1<<0), /* this is a version 4 route */
  368. Rifc= (1<<1), /* this route is a directly connected interface */
  369. Rptpt= (1<<2), /* this route is a pt to pt interface */
  370. Runi= (1<<3), /* a unicast self address */
  371. Rbcast= (1<<4), /* a broadcast self address */
  372. Rmulti= (1<<5), /* a multicast self address */
  373. Rproxy= (1<<6), /* this route should be proxied */
  374. };
  375. struct Routewalk
  376. {
  377. int n;
  378. int o;
  379. int h;
  380. char* p;
  381. void* state;
  382. void (*walk)(Route*, Routewalk*);
  383. };
  384. struct RouteTree
  385. {
  386. Route* right;
  387. Route* left;
  388. Route* mid;
  389. uchar depth;
  390. uchar type;
  391. uchar ifcid; /* must match ifc->id */
  392. Ipifc *ifc;
  393. char tag[4];
  394. int ref;
  395. };
  396. struct V4route
  397. {
  398. ulong address;
  399. ulong endaddress;
  400. uchar gate[IPv4addrlen];
  401. };
  402. struct V6route
  403. {
  404. ulong address[IPllen];
  405. ulong endaddress[IPllen];
  406. uchar gate[IPaddrlen];
  407. };
  408. struct Route
  409. {
  410. RouteTree;
  411. union {
  412. V6route v6;
  413. V4route v4;
  414. };
  415. };
  416. extern void v4addroute(Fs *f, char *tag, uchar *a, uchar *mask, uchar *gate, int type);
  417. extern void v6addroute(Fs *f, char *tag, uchar *a, uchar *mask, uchar *gate, int type);
  418. extern void v4delroute(Fs *f, uchar *a, uchar *mask, int dolock);
  419. extern void v6delroute(Fs *f, uchar *a, uchar *mask, int dolock);
  420. extern Route* v4lookup(Fs *f, uchar *a);
  421. extern Route* v6lookup(Fs *f, uchar *a);
  422. extern long routeread(Fs *f, char*, ulong, int);
  423. extern long routewrite(Fs *f, Chan*, char*, int);
  424. extern void routetype(int, char*);
  425. extern void ipwalkroutes(Fs*, Routewalk*);
  426. extern void convroute(Route*, uchar*, uchar*, uchar*, char*, int*);
  427. /*
  428. * devip.c
  429. */
  430. /*
  431. * Hanging off every ip channel's ->aux is the following structure.
  432. * It maintains the state used by devip and iproute.
  433. */
  434. struct IPaux
  435. {
  436. char *owner; /* the user that did the attach */
  437. char tag[4];
  438. };
  439. extern IPaux* newipaux(char*, char*);
  440. /*
  441. * arp.c
  442. */
  443. struct Arpent
  444. {
  445. uchar ip[IPaddrlen];
  446. uchar mac[MAClen];
  447. Medium *type; /* media type */
  448. Arpent* hash;
  449. Block* hold;
  450. Block* last;
  451. uint time;
  452. uint used;
  453. uchar state;
  454. Arpent *nextrxt; /* re-transmit chain */
  455. uint rxtat;
  456. uchar rxtsrem;
  457. Ipifc *ifc;
  458. uchar ifcid; /* must match ifc->id */
  459. };
  460. extern void arpinit(Fs*);
  461. extern int arpread(Arp*, char*, ulong, int);
  462. extern int arpwrite(Fs*, char*, int);
  463. extern Arpent* arpget(Arp*, Block *bp, int version, Ipifc *ifc, uchar *ip, uchar *h);
  464. extern void arprelease(Arp*, Arpent *a);
  465. extern Block* arpresolve(Arp*, Arpent *a, Medium *type, uchar *mac);
  466. extern void arpenter(Fs*, int version, uchar *ip, uchar *mac, int len, int norefresh);
  467. /*
  468. * ipaux.c
  469. */
  470. extern int myetheraddr(uchar*, char*);
  471. extern ulong parseip(uchar*, char*);
  472. extern ulong parseipmask(uchar*, char*);
  473. extern char* v4parseip(uchar*, char*);
  474. extern void maskip(uchar *from, uchar *mask, uchar *to);
  475. extern int parsemac(uchar *to, char *from, int len);
  476. extern uchar* defmask(uchar*);
  477. extern int isv4(uchar*);
  478. extern void v4tov6(uchar *v6, uchar *v4);
  479. extern int v6tov4(uchar *v4, uchar *v6);
  480. extern int eipfmt(Fmt*);
  481. #define ipmove(x, y) memmove(x, y, IPaddrlen)
  482. #define ipcmp(x, y) ( (x)[IPaddrlen-1] != (y)[IPaddrlen-1] || memcmp(x, y, IPaddrlen) )
  483. extern uchar IPv4bcast[IPaddrlen];
  484. extern uchar IPv4bcastobs[IPaddrlen];
  485. extern uchar IPv4allsys[IPaddrlen];
  486. extern uchar IPv4allrouter[IPaddrlen];
  487. extern uchar IPnoaddr[IPaddrlen];
  488. extern uchar v4prefix[IPaddrlen];
  489. extern uchar IPallbits[IPaddrlen];
  490. #define NOW TK2MS(MACHP(0)->ticks)
  491. /*
  492. * media
  493. */
  494. extern Medium ethermedium;
  495. extern Medium nullmedium;
  496. extern Medium pktmedium;
  497. extern Medium tripmedium;
  498. /*
  499. * ipifc.c
  500. */
  501. extern Medium* ipfindmedium(char *name);
  502. extern void addipmedium(Medium *med);
  503. extern int ipforme(Fs*, uchar *addr);
  504. extern int iptentative(Fs*, uchar *addr);
  505. extern int ipisbm(uchar *);
  506. extern int ipismulticast(uchar *);
  507. extern Ipifc* findipifc(Fs*, uchar *remote, int type);
  508. extern void findprimaryip(Fs*, uchar*);
  509. extern void findlocalip(Fs*, uchar *local, uchar *remote);
  510. extern int ipv4local(Ipifc *ifc, uchar *addr);
  511. extern int ipv6local(Ipifc *ifc, uchar *addr);
  512. extern int ipv6anylocal(Ipifc *ifc, uchar *addr);
  513. extern Iplifc* iplocalonifc(Ipifc *ifc, uchar *ip);
  514. extern int ipproxyifc(Fs *f, Ipifc *ifc, uchar *ip);
  515. extern int ipismulticast(uchar *ip);
  516. extern int ipisbooting(void);
  517. extern int ipifccheckin(Ipifc *ifc, Medium *med);
  518. extern void ipifccheckout(Ipifc *ifc);
  519. extern int ipifcgrab(Ipifc *ifc);
  520. extern void ipifcaddroute(Fs*, int, uchar*, uchar*, uchar*, int);
  521. extern void ipifcremroute(Fs*, int, uchar*, uchar*);
  522. extern void ipifcremmulti(Conv *c, uchar *ma, uchar *ia);
  523. extern void ipifcaddmulti(Conv *c, uchar *ma, uchar *ia);
  524. extern char* ipifcrem(Ipifc *ifc, char **argv, int argc, int dolock);
  525. extern char* ipifcadd(Ipifc *ifc, char **argv, int argc, int tentative, Iplifc *lifcp);
  526. extern long ipselftabread(Fs*, char *a, ulong offset, int n);
  527. extern char* ipifcaddgate6(Fs *f, Ipifc *ifc, char**argv, int argc);
  528. extern char* ipifcaddpref6(Ipifc *ifc, char**argv, int argc);
  529. extern void ipsendra6(Fs *f, int on);
  530. extern long ipgateread6(Fs *f, char *cp, ulong offset, int n);
  531. /*
  532. * ip.c
  533. */
  534. extern void iprouting(Fs*, int);
  535. extern void closeifcconv(Ifcconv*);
  536. extern void icmpnoconv(Fs*, Block*);
  537. extern void icmpcantfrag(Fs*, Block*, int);
  538. extern void icmpttlexceeded(Fs*, uchar*, Block*);
  539. extern ushort ipcsum(uchar*);
  540. extern void ipiput4(Fs*, Ipifc*, Block*);
  541. extern void ipiput6(Fs*, Ipifc*, Block*);
  542. extern int ipoput4(Fs*, Block*, int, int, int);
  543. extern int ipoput6(Fs*, Block*, int, int, int);
  544. extern int ipstats(Fs*, char*, int);
  545. extern ushort ptclbsum(uchar*, int);
  546. extern ushort ptclcsum(Block*, int, int);
  547. extern void ip_init(Fs*);
  548. extern void update_mtucache(uchar*, ulong);
  549. extern ulong restrict_mtu(uchar*, ulong);
  550. /*
  551. * bootp.c
  552. */
  553. extern char* bootp(Ipifc*);
  554. extern int bootpread(char*, ulong, int);
  555. /*
  556. * resolving inferno/plan9 differences
  557. */
  558. Chan* commonfdtochan(int, int, int, int);
  559. char* commonuser(void);
  560. char* commonerror(void);
  561. /*
  562. * chandial.c
  563. */
  564. extern Chan* chandial(char*, char*, char*, Chan**);
  565. /*
  566. * global to all of the stack
  567. */
  568. extern int debug;
  569. extern Fs fs;
  570. extern void (*igmpreportfn)(Ipifc*, uchar*);