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