ip.h 16 KB

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  1. typedef struct Conv Conv;
  2. typedef struct Fs Fs;
  3. typedef union Hwaddr Hwaddr;
  4. typedef struct IP IP;
  5. typedef struct IPaux IPaux;
  6. typedef struct Ipself Ipself;
  7. typedef struct Ipselftab Ipselftab;
  8. typedef struct Iplink Iplink;
  9. typedef struct Iplifc Iplifc;
  10. typedef struct Ipmulti Ipmulti;
  11. typedef struct Ipifc Ipifc;
  12. typedef struct Iphash Iphash;
  13. typedef struct Ipht Ipht;
  14. typedef struct Netlog Netlog;
  15. typedef struct Medium Medium;
  16. typedef struct Proto Proto;
  17. typedef struct Arpent Arpent;
  18. typedef struct Arp Arp;
  19. typedef struct Route Route;
  20. typedef struct Routerparams Routerparams;
  21. typedef struct Hostparams Hostparams;
  22. typedef struct v6router v6router;
  23. typedef struct v6params v6params;
  24. #pragma incomplete Arp
  25. #pragma incomplete Ipself
  26. #pragma incomplete Ipselftab
  27. #pragma incomplete IP
  28. #pragma incomplete Netlog
  29. enum
  30. {
  31. Addrlen= 64,
  32. Maxproto= 20,
  33. Nhash= 64,
  34. Maxincall= 5,
  35. Nchans= 1024,
  36. MAClen= 16, /* longest mac address */
  37. MAXTTL= 255,
  38. DFLTTOS= 0,
  39. IPaddrlen= 16,
  40. IPv4addrlen= 4,
  41. IPv4off= 12,
  42. IPllen= 4,
  43. /* ip versions */
  44. V4= 4,
  45. V6= 6,
  46. IP_VER4= 0x40,
  47. IP_VER6= 0x60,
  48. IP4HDR= 20, /* sizeof(Ip4hdr) */
  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. /* on the wire packet header */
  62. typedef struct Ip4hdr Ip4hdr;
  63. struct Ip4hdr
  64. {
  65. uchar vihl; /* Version and header length */
  66. uchar tos; /* Type of service */
  67. uchar length[2]; /* packet length */
  68. uchar id[2]; /* ip->identification */
  69. uchar frag[2]; /* Fragment information */
  70. uchar ttl; /* Time to live */
  71. uchar proto; /* Protocol */
  72. uchar cksum[2]; /* Header checksum */
  73. uchar src[4]; /* IP source */
  74. uchar dst[4]; /* IP destination */
  75. };
  76. /*
  77. * one per conversation directory
  78. */
  79. struct Conv
  80. {
  81. QLock;
  82. int x; /* conversation index */
  83. Proto* p;
  84. int restricted; /* remote port is restricted */
  85. uint ttl; /* max time to live */
  86. uint tos; /* type of service */
  87. int ignoreadvice; /* don't terminate connection on icmp errors */
  88. uchar ipversion;
  89. uchar laddr[IPaddrlen]; /* local IP address */
  90. uchar raddr[IPaddrlen]; /* remote IP address */
  91. ushort lport; /* local port number */
  92. ushort rport; /* remote port number */
  93. char *owner; /* protections */
  94. int perm;
  95. int inuse; /* opens of listen/data/ctl */
  96. int length;
  97. int state;
  98. /* udp specific */
  99. int headers; /* data src/dst headers in udp */
  100. int reliable; /* true if reliable udp */
  101. Conv* incall; /* calls waiting to be listened for */
  102. Conv* next;
  103. Queue* rq; /* queued data waiting to be read */
  104. Queue* wq; /* queued data waiting to be written */
  105. Queue* eq; /* returned error packets */
  106. Queue* sq; /* snooping queue */
  107. Ref snoopers; /* number of processes with snoop open */
  108. QLock car;
  109. Rendez cr;
  110. char cerr[ERRMAX];
  111. QLock listenq;
  112. Rendez listenr;
  113. Ipmulti *multi; /* multicast bindings for this interface */
  114. void* ptcl; /* protocol specific stuff */
  115. Route *r; /* last route used */
  116. ulong rgen; /* routetable generation for *r */
  117. };
  118. struct Medium
  119. {
  120. char *name;
  121. int hsize; /* medium header size */
  122. int mintu; /* default min mtu */
  123. int maxtu; /* default max mtu */
  124. int maclen; /* mac address length */
  125. void (*bind)(Ipifc*, int, char**);
  126. void (*unbind)(Ipifc*);
  127. void (*bwrite)(Ipifc *ifc, Block *b, int version, uchar *ip);
  128. /* for arming interfaces to receive multicast */
  129. void (*addmulti)(Ipifc *ifc, uchar *a, uchar *ia);
  130. void (*remmulti)(Ipifc *ifc, uchar *a, uchar *ia);
  131. /* process packets written to 'data' */
  132. void (*pktin)(Fs *f, Ipifc *ifc, Block *bp);
  133. /* routes for router boards */
  134. void (*addroute)(Ipifc *ifc, int, uchar*, uchar*, uchar*, int);
  135. void (*remroute)(Ipifc *ifc, int, uchar*, uchar*);
  136. void (*flushroutes)(Ipifc *ifc);
  137. /* for routing multicast groups */
  138. void (*joinmulti)(Ipifc *ifc, uchar *a, uchar *ia);
  139. void (*leavemulti)(Ipifc *ifc, uchar *a, uchar *ia);
  140. /* address resolution */
  141. void (*ares)(Fs*, int, uchar*, uchar*, int, int); /* resolve */
  142. void (*areg)(Ipifc*, uchar*); /* register */
  143. /* v6 address generation */
  144. void (*pref2addr)(uchar *pref, uchar *ea);
  145. int unbindonclose; /* if non-zero, unbind on last close */
  146. };
  147. /* logical interface associated with a physical one */
  148. struct Iplifc
  149. {
  150. uchar local[IPaddrlen];
  151. uchar mask[IPaddrlen];
  152. uchar remote[IPaddrlen];
  153. uchar net[IPaddrlen];
  154. uchar tentative; /* =1 => v6 dup disc on, =0 => confirmed unique */
  155. uchar onlink; /* =1 => onlink, =0 offlink. */
  156. uchar autoflag; /* v6 autonomous flag */
  157. long validlt; /* v6 valid lifetime */
  158. long preflt; /* v6 preferred lifetime */
  159. long origint; /* time when addr was added */
  160. Iplink *link; /* addresses linked to this lifc */
  161. Iplifc *next;
  162. };
  163. /* binding twixt Ipself and Iplifc */
  164. struct Iplink
  165. {
  166. Ipself *self;
  167. Iplifc *lifc;
  168. Iplink *selflink; /* next link for this local address */
  169. Iplink *lifclink; /* next link for this ifc */
  170. ulong expire;
  171. Iplink *next; /* free list */
  172. int ref;
  173. };
  174. /* rfc 2461, pp.40—43. */
  175. /* default values, one per stack */
  176. struct Routerparams {
  177. int mflag; /* flag: managed address configuration */
  178. int oflag; /* flag: other stateful configuration */
  179. int maxraint; /* max. router adv interval (ms) */
  180. int minraint; /* min. router adv interval (ms) */
  181. int linkmtu; /* mtu options */
  182. int reachtime; /* reachable time */
  183. int rxmitra; /* retransmit interval */
  184. int ttl; /* cur hop count limit */
  185. int routerlt; /* router lifetime */
  186. };
  187. struct Hostparams {
  188. int rxmithost;
  189. };
  190. struct Ipifc
  191. {
  192. RWlock;
  193. Conv *conv; /* link to its conversation structure */
  194. char dev[64]; /* device we're attached to */
  195. Medium *m; /* Media pointer */
  196. int maxtu; /* Maximum transfer unit */
  197. int mintu; /* Minumum tranfer unit */
  198. int mbps; /* megabits per second */
  199. void *arg; /* medium specific */
  200. int reassemble; /* reassemble IP packets before forwarding */
  201. /* these are used so that we can unbind on the fly */
  202. Lock idlock;
  203. uchar ifcid; /* incremented each 'bind/unbind/add/remove' */
  204. int ref; /* number of proc's using this ipifc */
  205. Rendez wait; /* where unbinder waits for ref == 0 */
  206. int unbinding;
  207. uchar mac[MAClen]; /* MAC address */
  208. Iplifc *lifc; /* logical interfaces on this physical one */
  209. ulong in, out; /* message statistics */
  210. ulong inerr, outerr; /* ... */
  211. uchar sendra6; /* flag: send router advs on this ifc */
  212. uchar recvra6; /* flag: recv router advs on this ifc */
  213. Routerparams rp; /* router parameters as in RFC 2461, pp.40—43.
  214. used only if node is router */
  215. };
  216. /*
  217. * one per multicast-lifc pair used by a Conv
  218. */
  219. struct Ipmulti
  220. {
  221. uchar ma[IPaddrlen];
  222. uchar ia[IPaddrlen];
  223. Ipmulti *next;
  224. };
  225. /*
  226. * hash table for 2 ip addresses + 2 ports
  227. */
  228. enum
  229. {
  230. Nipht= 521, /* convenient prime */
  231. IPmatchexact= 0, /* match on 4 tuple */
  232. IPmatchany, /* *!* */
  233. IPmatchport, /* *!port */
  234. IPmatchaddr, /* addr!* */
  235. IPmatchpa, /* addr!port */
  236. };
  237. struct Iphash
  238. {
  239. Iphash *next;
  240. Conv *c;
  241. int match;
  242. };
  243. struct Ipht
  244. {
  245. Lock;
  246. Iphash *tab[Nipht];
  247. };
  248. void iphtadd(Ipht*, Conv*);
  249. void iphtrem(Ipht*, Conv*);
  250. Conv* iphtlook(Ipht *ht, uchar *sa, ushort sp, uchar *da, ushort dp);
  251. /*
  252. * one per multiplexed protocol
  253. */
  254. struct Proto
  255. {
  256. QLock;
  257. char* name; /* protocol name */
  258. int x; /* protocol index */
  259. int ipproto; /* ip protocol type */
  260. char* (*connect)(Conv*, char**, int);
  261. char* (*announce)(Conv*, char**, int);
  262. char* (*bind)(Conv*, char**, int);
  263. int (*state)(Conv*, char*, int);
  264. void (*create)(Conv*);
  265. void (*close)(Conv*);
  266. void (*rcv)(Proto*, Ipifc*, Block*);
  267. char* (*ctl)(Conv*, char**, int);
  268. void (*advise)(Proto*, Block*, char*);
  269. int (*stats)(Proto*, char*, int);
  270. int (*local)(Conv*, char*, int);
  271. int (*remote)(Conv*, char*, int);
  272. int (*inuse)(Conv*);
  273. int (*gc)(Proto*); /* returns true if any conversations are freed */
  274. Fs *f; /* file system this proto is part of */
  275. Conv **conv; /* array of conversations */
  276. int ptclsize; /* size of per protocol ctl block */
  277. int nc; /* number of conversations */
  278. int ac;
  279. Qid qid; /* qid for protocol directory */
  280. ushort nextport;
  281. ushort nextrport;
  282. void *priv;
  283. };
  284. /*
  285. * one per IP protocol stack
  286. */
  287. struct Fs
  288. {
  289. RWlock;
  290. int dev;
  291. int np;
  292. Proto* p[Maxproto+1]; /* list of supported protocols */
  293. Proto* t2p[256]; /* vector of all protocols */
  294. Proto* ipifc; /* kludge for ipifcremroute & ipifcaddroute */
  295. Proto* ipmux; /* kludge for finding an ip multiplexor */
  296. IP *ip;
  297. Ipselftab *self;
  298. Arp *arp;
  299. v6params *v6p;
  300. Route *v4root[1<<Lroot]; /* v4 routing forest */
  301. Route *v6root[1<<Lroot]; /* v6 routing forest */
  302. Route *queue; /* used as temp when reinjecting routes */
  303. Netlog *alog;
  304. char ndb[1024]; /* an ndb entry for this interface */
  305. int ndbvers;
  306. long ndbmtime;
  307. };
  308. /* one per default router known to host */
  309. struct v6router {
  310. uchar inuse;
  311. Ipifc *ifc;
  312. int ifcid;
  313. uchar routeraddr[IPaddrlen];
  314. long ltorigin;
  315. Routerparams rp;
  316. };
  317. struct v6params
  318. {
  319. Routerparams rp; /* v6 params, one copy per node now */
  320. Hostparams hp;
  321. v6router v6rlist[3]; /* max 3 default routers, currently */
  322. int cdrouter; /* uses only v6rlist[cdrouter] if */
  323. /* cdrouter >= 0. */
  324. };
  325. int Fsconnected(Conv*, char*);
  326. Conv* Fsnewcall(Conv*, uchar*, ushort, uchar*, ushort, uchar);
  327. int Fspcolstats(char*, int);
  328. int Fsproto(Fs*, Proto*);
  329. int Fsbuiltinproto(Fs*, uchar);
  330. Conv* Fsprotoclone(Proto*, char*);
  331. Proto* Fsrcvpcol(Fs*, uchar);
  332. Proto* Fsrcvpcolx(Fs*, uchar);
  333. char* Fsstdconnect(Conv*, char**, int);
  334. char* Fsstdannounce(Conv*, char**, int);
  335. char* Fsstdbind(Conv*, char**, int);
  336. ulong scalednconv(void);
  337. void closeconv(Conv*);
  338. /*
  339. * logging
  340. */
  341. enum
  342. {
  343. Logip= 1<<1,
  344. Logtcp= 1<<2,
  345. Logfs= 1<<3,
  346. Logil= 1<<4,
  347. Logicmp= 1<<5,
  348. Logudp= 1<<6,
  349. Logcompress= 1<<7,
  350. Logilmsg= 1<<8,
  351. Loggre= 1<<9,
  352. Logppp= 1<<10,
  353. Logtcprxmt= 1<<11,
  354. Logigmp= 1<<12,
  355. Logudpmsg= 1<<13,
  356. Logipmsg= 1<<14,
  357. Logrudp= 1<<15,
  358. Logrudpmsg= 1<<16,
  359. Logesp= 1<<17,
  360. Logtcpwin= 1<<18,
  361. };
  362. void netloginit(Fs*);
  363. void netlogopen(Fs*);
  364. void netlogclose(Fs*);
  365. void netlogctl(Fs*, char*, int);
  366. long netlogread(Fs*, void*, ulong, long);
  367. void netlog(Fs*, int, char*, ...);
  368. void ifcloginit(Fs*);
  369. long ifclogread(Fs*, Chan *,void*, ulong, long);
  370. void ifclog(Fs*, uchar *, int);
  371. void ifclogopen(Fs*, Chan*);
  372. void ifclogclose(Fs*, Chan*);
  373. /*
  374. * iproute.c
  375. */
  376. typedef struct RouteTree RouteTree;
  377. typedef struct Routewalk Routewalk;
  378. typedef struct V4route V4route;
  379. typedef struct V6route V6route;
  380. enum
  381. {
  382. /* type bits */
  383. Rv4= (1<<0), /* this is a version 4 route */
  384. Rifc= (1<<1), /* this route is a directly connected interface */
  385. Rptpt= (1<<2), /* this route is a pt to pt interface */
  386. Runi= (1<<3), /* a unicast self address */
  387. Rbcast= (1<<4), /* a broadcast self address */
  388. Rmulti= (1<<5), /* a multicast self address */
  389. Rproxy= (1<<6), /* this route should be proxied */
  390. };
  391. struct Routewalk
  392. {
  393. int o;
  394. int h;
  395. char* p;
  396. char* e;
  397. void* state;
  398. void (*walk)(Route*, Routewalk*);
  399. };
  400. struct RouteTree
  401. {
  402. Route* right;
  403. Route* left;
  404. Route* mid;
  405. uchar depth;
  406. uchar type;
  407. uchar ifcid; /* must match ifc->id */
  408. Ipifc *ifc;
  409. char tag[4];
  410. int ref;
  411. };
  412. struct V4route
  413. {
  414. ulong address;
  415. ulong endaddress;
  416. uchar gate[IPv4addrlen];
  417. };
  418. struct V6route
  419. {
  420. ulong address[IPllen];
  421. ulong endaddress[IPllen];
  422. uchar gate[IPaddrlen];
  423. };
  424. struct Route
  425. {
  426. RouteTree;
  427. union {
  428. V6route v6;
  429. V4route v4;
  430. };
  431. };
  432. extern void v4addroute(Fs *f, char *tag, uchar *a, uchar *mask, uchar *gate, int type);
  433. extern void v6addroute(Fs *f, char *tag, uchar *a, uchar *mask, uchar *gate, int type);
  434. extern void v4delroute(Fs *f, uchar *a, uchar *mask, int dolock);
  435. extern void v6delroute(Fs *f, uchar *a, uchar *mask, int dolock);
  436. extern Route* v4lookup(Fs *f, uchar *a, Conv *c);
  437. extern Route* v6lookup(Fs *f, uchar *a, Conv *c);
  438. extern long routeread(Fs *f, char*, ulong, int);
  439. extern long routewrite(Fs *f, Chan*, char*, int);
  440. extern void routetype(int, char*);
  441. extern void ipwalkroutes(Fs*, Routewalk*);
  442. extern void convroute(Route*, uchar*, uchar*, uchar*, char*, int*);
  443. /*
  444. * devip.c
  445. */
  446. /*
  447. * Hanging off every ip channel's ->aux is the following structure.
  448. * It maintains the state used by devip and iproute.
  449. */
  450. struct IPaux
  451. {
  452. char *owner; /* the user that did the attach */
  453. char tag[4];
  454. };
  455. extern IPaux* newipaux(char*, char*);
  456. /*
  457. * arp.c
  458. */
  459. struct Arpent
  460. {
  461. uchar ip[IPaddrlen];
  462. uchar mac[MAClen];
  463. Medium *type; /* media type */
  464. Arpent* hash;
  465. Block* hold;
  466. Block* last;
  467. uint ctime; /* time entry was created or refreshed */
  468. uint utime; /* time entry was last used */
  469. uchar state;
  470. Arpent *nextrxt; /* re-transmit chain */
  471. uint rtime; /* time for next retransmission */
  472. uchar rxtsrem;
  473. Ipifc *ifc;
  474. uchar ifcid; /* must match ifc->id */
  475. };
  476. extern void arpinit(Fs*);
  477. extern int arpread(Arp*, char*, ulong, int);
  478. extern int arpwrite(Fs*, char*, int);
  479. extern Arpent* arpget(Arp*, Block *bp, int version, Ipifc *ifc, uchar *ip, uchar *h);
  480. extern void arprelease(Arp*, Arpent *a);
  481. extern Block* arpresolve(Arp*, Arpent *a, Medium *type, uchar *mac);
  482. extern void arpenter(Fs*, int version, uchar *ip, uchar *mac, int len, int norefresh);
  483. /*
  484. * ipaux.c
  485. */
  486. extern int myetheraddr(uchar*, char*);
  487. extern ulong parseip(uchar*, char*);
  488. extern ulong parseipmask(uchar*, char*);
  489. extern char* v4parseip(uchar*, char*);
  490. extern void maskip(uchar *from, uchar *mask, uchar *to);
  491. extern int parsemac(uchar *to, char *from, int len);
  492. extern uchar* defmask(uchar*);
  493. extern int isv4(uchar*);
  494. extern void v4tov6(uchar *v6, uchar *v4);
  495. extern int v6tov4(uchar *v4, uchar *v6);
  496. extern int eipfmt(Fmt*);
  497. #define ipmove(x, y) memmove(x, y, IPaddrlen)
  498. #define ipcmp(x, y) ( (x)[IPaddrlen-1] != (y)[IPaddrlen-1] || memcmp(x, y, IPaddrlen) )
  499. extern uchar IPv4bcast[IPaddrlen];
  500. extern uchar IPv4bcastobs[IPaddrlen];
  501. extern uchar IPv4allsys[IPaddrlen];
  502. extern uchar IPv4allrouter[IPaddrlen];
  503. extern uchar IPnoaddr[IPaddrlen];
  504. extern uchar v4prefix[IPaddrlen];
  505. extern uchar IPallbits[IPaddrlen];
  506. #define NOW TK2MS(MACHP(0)->ticks)
  507. /*
  508. * media
  509. */
  510. extern Medium ethermedium;
  511. extern Medium nullmedium;
  512. extern Medium pktmedium;
  513. extern Medium tripmedium;
  514. /*
  515. * ipifc.c
  516. */
  517. extern Medium* ipfindmedium(char *name);
  518. extern void addipmedium(Medium *med);
  519. extern int ipforme(Fs*, uchar *addr);
  520. extern int iptentative(Fs*, uchar *addr);
  521. extern int ipisbm(uchar *);
  522. extern int ipismulticast(uchar *);
  523. extern Ipifc* findipifc(Fs*, uchar *remote, int type);
  524. extern void findlocalip(Fs*, uchar *local, uchar *remote);
  525. extern int ipv4local(Ipifc *ifc, uchar *addr);
  526. extern int ipv6local(Ipifc *ifc, uchar *addr);
  527. extern int ipv6anylocal(Ipifc *ifc, uchar *addr);
  528. extern Iplifc* iplocalonifc(Ipifc *ifc, uchar *ip);
  529. extern int ipproxyifc(Fs *f, Ipifc *ifc, uchar *ip);
  530. extern int ipismulticast(uchar *ip);
  531. extern int ipisbooting(void);
  532. extern int ipifccheckin(Ipifc *ifc, Medium *med);
  533. extern void ipifccheckout(Ipifc *ifc);
  534. extern int ipifcgrab(Ipifc *ifc);
  535. extern void ipifcaddroute(Fs*, int, uchar*, uchar*, uchar*, int);
  536. extern void ipifcremroute(Fs*, int, uchar*, uchar*);
  537. extern void ipifcremmulti(Conv *c, uchar *ma, uchar *ia);
  538. extern void ipifcaddmulti(Conv *c, uchar *ma, uchar *ia);
  539. extern char* ipifcrem(Ipifc *ifc, char **argv, int argc);
  540. extern char* ipifcadd(Ipifc *ifc, char **argv, int argc, int tentative, Iplifc *lifcp);
  541. extern long ipselftabread(Fs*, char *a, ulong offset, int n);
  542. extern char* ipifcadd6(Ipifc *ifc, char**argv, int argc);
  543. /*
  544. * ip.c
  545. */
  546. extern void iprouting(Fs*, int);
  547. extern void icmpnoconv(Fs*, Block*);
  548. extern void icmpcantfrag(Fs*, Block*, int);
  549. extern void icmpttlexceeded(Fs*, uchar*, Block*);
  550. extern ushort ipcsum(uchar*);
  551. extern void ipiput4(Fs*, Ipifc*, Block*);
  552. extern void ipiput6(Fs*, Ipifc*, Block*);
  553. extern int ipoput4(Fs*, Block*, int, int, int, Conv*);
  554. extern int ipoput6(Fs*, Block*, int, int, int, Conv*);
  555. extern int ipstats(Fs*, char*, int);
  556. extern ushort ptclbsum(uchar*, int);
  557. extern ushort ptclcsum(Block*, int, int);
  558. extern void ip_init(Fs*);
  559. extern void update_mtucache(uchar*, ulong);
  560. extern ulong restrict_mtu(uchar*, ulong);
  561. /*
  562. * bootp.c
  563. */
  564. extern char* bootp(Ipifc*);
  565. extern int bootpread(char*, ulong, int);
  566. /*
  567. * resolving inferno/plan9 differences
  568. */
  569. Chan* commonfdtochan(int, int, int, int);
  570. char* commonuser(void);
  571. char* commonerror(void);
  572. /*
  573. * chandial.c
  574. */
  575. extern Chan* chandial(char*, char*, char*, Chan**);
  576. /*
  577. * global to all of the stack
  578. */
  579. extern void (*igmpreportfn)(Ipifc*, uchar*);