sm_sideeffect.c 44 KB

123456789101112131415161718192021222324252627282930313233343536373839404142434445464748495051525354555657585960616263646566676869707172737475767778798081828384858687888990919293949596979899100101102103104105106107108109110111112113114115116117118119120121122123124125126127128129130131132133134135136137138139140141142143144145146147148149150151152153154155156157158159160161162163164165166167168169170171172173174175176177178179180181182183184185186187188189190191192193194195196197198199200201202203204205206207208209210211212213214215216217218219220221222223224225226227228229230231232233234235236237238239240241242243244245246247248249250251252253254255256257258259260261262263264265266267268269270271272273274275276277278279280281282283284285286287288289290291292293294295296297298299300301302303304305306307308309310311312313314315316317318319320321322323324325326327328329330331332333334335336337338339340341342343344345346347348349350351352353354355356357358359360361362363364365366367368369370371372373374375376377378379380381382383384385386387388389390391392393394395396397398399400401402403404405406407408409410411412413414415416417418419420421422423424425426427428429430431432433434435436437438439440441442443444445446447448449450451452453454455456457458459460461462463464465466467468469470471472473474475476477478479480481482483484485486487488489490491492493494495496497498499500501502503504505506507508509510511512513514515516517518519520521522523524525526527528529530531532533534535536537538539540541542543544545546547548549550551552553554555556557558559560561562563564565566567568569570571572573574575576577578579580581582583584585586587588589590591592593594595596597598599600601602603604605606607608609610611612613614615616617618619620621622623624625626627628629630631632633634635636637638639640641642643644645646647648649650651652653654655656657658659660661662663664665666667668669670671672673674675676677678679680681682683684685686687688689690691692693694695696697698699700701702703704705706707708709710711712713714715716717718719720721722723724725726727728729730731732733734735736737738739740741742743744745746747748749750751752753754755756757758759760761762763764765766767768769770771772773774775776777778779780781782783784785786787788789790791792793794795796797798799800801802803804805806807808809810811812813814815816817818819820821822823824825826827828829830831832833834835836837838839840841842843844845846847848849850851852853854855856857858859860861862863864865866867868869870871872873874875876877878879880881882883884885886887888889890891892893894895896897898899900901902903904905906907908909910911912913914915916917918919920921922923924925926927928929930931932933934935936937938939940941942943944945946947948949950951952953954955956957958959960961962963964965966967968969970971972973974975976977978979980981982983984985986987988989990991992993994995996997998999100010011002100310041005100610071008100910101011101210131014101510161017101810191020102110221023102410251026102710281029103010311032103310341035103610371038103910401041104210431044104510461047104810491050105110521053105410551056105710581059106010611062106310641065106610671068106910701071107210731074107510761077107810791080108110821083108410851086108710881089109010911092109310941095109610971098109911001101110211031104110511061107110811091110111111121113111411151116111711181119112011211122112311241125112611271128112911301131113211331134113511361137113811391140114111421143114411451146114711481149115011511152115311541155115611571158115911601161116211631164116511661167116811691170117111721173117411751176117711781179118011811182118311841185118611871188118911901191119211931194119511961197119811991200120112021203120412051206120712081209121012111212121312141215121612171218121912201221122212231224122512261227122812291230123112321233123412351236123712381239124012411242124312441245124612471248124912501251125212531254125512561257125812591260126112621263126412651266126712681269127012711272127312741275127612771278127912801281128212831284128512861287128812891290129112921293129412951296129712981299130013011302130313041305130613071308130913101311131213131314131513161317131813191320132113221323132413251326132713281329133013311332133313341335133613371338133913401341134213431344134513461347134813491350135113521353135413551356135713581359136013611362136313641365136613671368136913701371137213731374137513761377137813791380138113821383138413851386138713881389139013911392139313941395139613971398139914001401140214031404140514061407140814091410141114121413141414151416141714181419142014211422142314241425142614271428142914301431143214331434143514361437143814391440144114421443144414451446144714481449145014511452145314541455145614571458145914601461146214631464146514661467146814691470147114721473147414751476147714781479148014811482148314841485148614871488148914901491149214931494149514961497149814991500150115021503150415051506150715081509151015111512151315141515151615171518151915201521152215231524152515261527152815291530153115321533153415351536153715381539154015411542154315441545154615471548154915501551155215531554155515561557155815591560156115621563156415651566156715681569157015711572
  1. /* SCTP kernel implementation
  2. * (C) Copyright IBM Corp. 2001, 2004
  3. * Copyright (c) 1999 Cisco, Inc.
  4. * Copyright (c) 1999-2001 Motorola, Inc.
  5. *
  6. * This file is part of the SCTP kernel implementation
  7. *
  8. * These functions work with the state functions in sctp_sm_statefuns.c
  9. * to implement that state operations. These functions implement the
  10. * steps which require modifying existing data structures.
  11. *
  12. * This SCTP implementation is free software;
  13. * you can redistribute it and/or modify it under the terms of
  14. * the GNU General Public License as published by
  15. * the Free Software Foundation; either version 2, or (at your option)
  16. * any later version.
  17. *
  18. * This SCTP implementation is distributed in the hope that it
  19. * will be useful, but WITHOUT ANY WARRANTY; without even the implied
  20. * ************************
  21. * warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
  22. * See the GNU General Public License for more details.
  23. *
  24. * You should have received a copy of the GNU General Public License
  25. * along with GNU CC; see the file COPYING. If not, write to
  26. * the Free Software Foundation, 59 Temple Place - Suite 330,
  27. * Boston, MA 02111-1307, USA.
  28. *
  29. * Please send any bug reports or fixes you make to the
  30. * email address(es):
  31. * lksctp developers <lksctp-developers@lists.sourceforge.net>
  32. *
  33. * Or submit a bug report through the following website:
  34. * http://www.sf.net/projects/lksctp
  35. *
  36. * Written or modified by:
  37. * La Monte H.P. Yarroll <piggy@acm.org>
  38. * Karl Knutson <karl@athena.chicago.il.us>
  39. * Jon Grimm <jgrimm@austin.ibm.com>
  40. * Hui Huang <hui.huang@nokia.com>
  41. * Dajiang Zhang <dajiang.zhang@nokia.com>
  42. * Daisy Chang <daisyc@us.ibm.com>
  43. * Sridhar Samudrala <sri@us.ibm.com>
  44. * Ardelle Fan <ardelle.fan@intel.com>
  45. *
  46. * Any bugs reported given to us we will try to fix... any fixes shared will
  47. * be incorporated into the next SCTP release.
  48. */
  49. #include <linux/skbuff.h>
  50. #include <linux/types.h>
  51. #include <linux/socket.h>
  52. #include <linux/ip.h>
  53. #include <net/sock.h>
  54. #include <net/sctp/sctp.h>
  55. #include <net/sctp/sm.h>
  56. static int sctp_cmd_interpreter(sctp_event_t event_type,
  57. sctp_subtype_t subtype,
  58. sctp_state_t state,
  59. struct sctp_endpoint *ep,
  60. struct sctp_association *asoc,
  61. void *event_arg,
  62. sctp_disposition_t status,
  63. sctp_cmd_seq_t *commands,
  64. gfp_t gfp);
  65. static int sctp_side_effects(sctp_event_t event_type, sctp_subtype_t subtype,
  66. sctp_state_t state,
  67. struct sctp_endpoint *ep,
  68. struct sctp_association *asoc,
  69. void *event_arg,
  70. sctp_disposition_t status,
  71. sctp_cmd_seq_t *commands,
  72. gfp_t gfp);
  73. /********************************************************************
  74. * Helper functions
  75. ********************************************************************/
  76. /* A helper function for delayed processing of INET ECN CE bit. */
  77. static void sctp_do_ecn_ce_work(struct sctp_association *asoc,
  78. __u32 lowest_tsn)
  79. {
  80. /* Save the TSN away for comparison when we receive CWR */
  81. asoc->last_ecne_tsn = lowest_tsn;
  82. asoc->need_ecne = 1;
  83. }
  84. /* Helper function for delayed processing of SCTP ECNE chunk. */
  85. /* RFC 2960 Appendix A
  86. *
  87. * RFC 2481 details a specific bit for a sender to send in
  88. * the header of its next outbound TCP segment to indicate to
  89. * its peer that it has reduced its congestion window. This
  90. * is termed the CWR bit. For SCTP the same indication is made
  91. * by including the CWR chunk. This chunk contains one data
  92. * element, i.e. the TSN number that was sent in the ECNE chunk.
  93. * This element represents the lowest TSN number in the datagram
  94. * that was originally marked with the CE bit.
  95. */
  96. static struct sctp_chunk *sctp_do_ecn_ecne_work(struct sctp_association *asoc,
  97. __u32 lowest_tsn,
  98. struct sctp_chunk *chunk)
  99. {
  100. struct sctp_chunk *repl;
  101. /* Our previously transmitted packet ran into some congestion
  102. * so we should take action by reducing cwnd and ssthresh
  103. * and then ACK our peer that we we've done so by
  104. * sending a CWR.
  105. */
  106. /* First, try to determine if we want to actually lower
  107. * our cwnd variables. Only lower them if the ECNE looks more
  108. * recent than the last response.
  109. */
  110. if (TSN_lt(asoc->last_cwr_tsn, lowest_tsn)) {
  111. struct sctp_transport *transport;
  112. /* Find which transport's congestion variables
  113. * need to be adjusted.
  114. */
  115. transport = sctp_assoc_lookup_tsn(asoc, lowest_tsn);
  116. /* Update the congestion variables. */
  117. if (transport)
  118. sctp_transport_lower_cwnd(transport,
  119. SCTP_LOWER_CWND_ECNE);
  120. asoc->last_cwr_tsn = lowest_tsn;
  121. }
  122. /* Always try to quiet the other end. In case of lost CWR,
  123. * resend last_cwr_tsn.
  124. */
  125. repl = sctp_make_cwr(asoc, asoc->last_cwr_tsn, chunk);
  126. /* If we run out of memory, it will look like a lost CWR. We'll
  127. * get back in sync eventually.
  128. */
  129. return repl;
  130. }
  131. /* Helper function to do delayed processing of ECN CWR chunk. */
  132. static void sctp_do_ecn_cwr_work(struct sctp_association *asoc,
  133. __u32 lowest_tsn)
  134. {
  135. /* Turn off ECNE getting auto-prepended to every outgoing
  136. * packet
  137. */
  138. asoc->need_ecne = 0;
  139. }
  140. /* Generate SACK if necessary. We call this at the end of a packet. */
  141. static int sctp_gen_sack(struct sctp_association *asoc, int force,
  142. sctp_cmd_seq_t *commands)
  143. {
  144. __u32 ctsn, max_tsn_seen;
  145. struct sctp_chunk *sack;
  146. struct sctp_transport *trans = asoc->peer.last_data_from;
  147. int error = 0;
  148. if (force ||
  149. (!trans && (asoc->param_flags & SPP_SACKDELAY_DISABLE)) ||
  150. (trans && (trans->param_flags & SPP_SACKDELAY_DISABLE)))
  151. asoc->peer.sack_needed = 1;
  152. ctsn = sctp_tsnmap_get_ctsn(&asoc->peer.tsn_map);
  153. max_tsn_seen = sctp_tsnmap_get_max_tsn_seen(&asoc->peer.tsn_map);
  154. /* From 12.2 Parameters necessary per association (i.e. the TCB):
  155. *
  156. * Ack State : This flag indicates if the next received packet
  157. * : is to be responded to with a SACK. ...
  158. * : When DATA chunks are out of order, SACK's
  159. * : are not delayed (see Section 6).
  160. *
  161. * [This is actually not mentioned in Section 6, but we
  162. * implement it here anyway. --piggy]
  163. */
  164. if (max_tsn_seen != ctsn)
  165. asoc->peer.sack_needed = 1;
  166. /* From 6.2 Acknowledgement on Reception of DATA Chunks:
  167. *
  168. * Section 4.2 of [RFC2581] SHOULD be followed. Specifically,
  169. * an acknowledgement SHOULD be generated for at least every
  170. * second packet (not every second DATA chunk) received, and
  171. * SHOULD be generated within 200 ms of the arrival of any
  172. * unacknowledged DATA chunk. ...
  173. */
  174. if (!asoc->peer.sack_needed) {
  175. asoc->peer.sack_cnt++;
  176. /* Set the SACK delay timeout based on the
  177. * SACK delay for the last transport
  178. * data was received from, or the default
  179. * for the association.
  180. */
  181. if (trans) {
  182. /* We will need a SACK for the next packet. */
  183. if (asoc->peer.sack_cnt >= trans->sackfreq - 1)
  184. asoc->peer.sack_needed = 1;
  185. asoc->timeouts[SCTP_EVENT_TIMEOUT_SACK] =
  186. trans->sackdelay;
  187. } else {
  188. /* We will need a SACK for the next packet. */
  189. if (asoc->peer.sack_cnt >= asoc->sackfreq - 1)
  190. asoc->peer.sack_needed = 1;
  191. asoc->timeouts[SCTP_EVENT_TIMEOUT_SACK] =
  192. asoc->sackdelay;
  193. }
  194. /* Restart the SACK timer. */
  195. sctp_add_cmd_sf(commands, SCTP_CMD_TIMER_RESTART,
  196. SCTP_TO(SCTP_EVENT_TIMEOUT_SACK));
  197. } else {
  198. if (asoc->a_rwnd > asoc->rwnd)
  199. asoc->a_rwnd = asoc->rwnd;
  200. sack = sctp_make_sack(asoc);
  201. if (!sack)
  202. goto nomem;
  203. asoc->peer.sack_needed = 0;
  204. asoc->peer.sack_cnt = 0;
  205. sctp_add_cmd_sf(commands, SCTP_CMD_REPLY, SCTP_CHUNK(sack));
  206. /* Stop the SACK timer. */
  207. sctp_add_cmd_sf(commands, SCTP_CMD_TIMER_STOP,
  208. SCTP_TO(SCTP_EVENT_TIMEOUT_SACK));
  209. }
  210. return error;
  211. nomem:
  212. error = -ENOMEM;
  213. return error;
  214. }
  215. /* When the T3-RTX timer expires, it calls this function to create the
  216. * relevant state machine event.
  217. */
  218. void sctp_generate_t3_rtx_event(unsigned long peer)
  219. {
  220. int error;
  221. struct sctp_transport *transport = (struct sctp_transport *) peer;
  222. struct sctp_association *asoc = transport->asoc;
  223. /* Check whether a task is in the sock. */
  224. sctp_bh_lock_sock(asoc->base.sk);
  225. if (sock_owned_by_user(asoc->base.sk)) {
  226. SCTP_DEBUG_PRINTK("%s:Sock is busy.\n", __func__);
  227. /* Try again later. */
  228. if (!mod_timer(&transport->T3_rtx_timer, jiffies + (HZ/20)))
  229. sctp_transport_hold(transport);
  230. goto out_unlock;
  231. }
  232. /* Is this transport really dead and just waiting around for
  233. * the timer to let go of the reference?
  234. */
  235. if (transport->dead)
  236. goto out_unlock;
  237. /* Run through the state machine. */
  238. error = sctp_do_sm(SCTP_EVENT_T_TIMEOUT,
  239. SCTP_ST_TIMEOUT(SCTP_EVENT_TIMEOUT_T3_RTX),
  240. asoc->state,
  241. asoc->ep, asoc,
  242. transport, GFP_ATOMIC);
  243. if (error)
  244. asoc->base.sk->sk_err = -error;
  245. out_unlock:
  246. sctp_bh_unlock_sock(asoc->base.sk);
  247. sctp_transport_put(transport);
  248. }
  249. /* This is a sa interface for producing timeout events. It works
  250. * for timeouts which use the association as their parameter.
  251. */
  252. static void sctp_generate_timeout_event(struct sctp_association *asoc,
  253. sctp_event_timeout_t timeout_type)
  254. {
  255. int error = 0;
  256. sctp_bh_lock_sock(asoc->base.sk);
  257. if (sock_owned_by_user(asoc->base.sk)) {
  258. SCTP_DEBUG_PRINTK("%s:Sock is busy: timer %d\n",
  259. __func__,
  260. timeout_type);
  261. /* Try again later. */
  262. if (!mod_timer(&asoc->timers[timeout_type], jiffies + (HZ/20)))
  263. sctp_association_hold(asoc);
  264. goto out_unlock;
  265. }
  266. /* Is this association really dead and just waiting around for
  267. * the timer to let go of the reference?
  268. */
  269. if (asoc->base.dead)
  270. goto out_unlock;
  271. /* Run through the state machine. */
  272. error = sctp_do_sm(SCTP_EVENT_T_TIMEOUT,
  273. SCTP_ST_TIMEOUT(timeout_type),
  274. asoc->state, asoc->ep, asoc,
  275. (void *)timeout_type, GFP_ATOMIC);
  276. if (error)
  277. asoc->base.sk->sk_err = -error;
  278. out_unlock:
  279. sctp_bh_unlock_sock(asoc->base.sk);
  280. sctp_association_put(asoc);
  281. }
  282. static void sctp_generate_t1_cookie_event(unsigned long data)
  283. {
  284. struct sctp_association *asoc = (struct sctp_association *) data;
  285. sctp_generate_timeout_event(asoc, SCTP_EVENT_TIMEOUT_T1_COOKIE);
  286. }
  287. static void sctp_generate_t1_init_event(unsigned long data)
  288. {
  289. struct sctp_association *asoc = (struct sctp_association *) data;
  290. sctp_generate_timeout_event(asoc, SCTP_EVENT_TIMEOUT_T1_INIT);
  291. }
  292. static void sctp_generate_t2_shutdown_event(unsigned long data)
  293. {
  294. struct sctp_association *asoc = (struct sctp_association *) data;
  295. sctp_generate_timeout_event(asoc, SCTP_EVENT_TIMEOUT_T2_SHUTDOWN);
  296. }
  297. static void sctp_generate_t4_rto_event(unsigned long data)
  298. {
  299. struct sctp_association *asoc = (struct sctp_association *) data;
  300. sctp_generate_timeout_event(asoc, SCTP_EVENT_TIMEOUT_T4_RTO);
  301. }
  302. static void sctp_generate_t5_shutdown_guard_event(unsigned long data)
  303. {
  304. struct sctp_association *asoc = (struct sctp_association *)data;
  305. sctp_generate_timeout_event(asoc,
  306. SCTP_EVENT_TIMEOUT_T5_SHUTDOWN_GUARD);
  307. } /* sctp_generate_t5_shutdown_guard_event() */
  308. static void sctp_generate_autoclose_event(unsigned long data)
  309. {
  310. struct sctp_association *asoc = (struct sctp_association *) data;
  311. sctp_generate_timeout_event(asoc, SCTP_EVENT_TIMEOUT_AUTOCLOSE);
  312. }
  313. /* Generate a heart beat event. If the sock is busy, reschedule. Make
  314. * sure that the transport is still valid.
  315. */
  316. void sctp_generate_heartbeat_event(unsigned long data)
  317. {
  318. int error = 0;
  319. struct sctp_transport *transport = (struct sctp_transport *) data;
  320. struct sctp_association *asoc = transport->asoc;
  321. sctp_bh_lock_sock(asoc->base.sk);
  322. if (sock_owned_by_user(asoc->base.sk)) {
  323. SCTP_DEBUG_PRINTK("%s:Sock is busy.\n", __func__);
  324. /* Try again later. */
  325. if (!mod_timer(&transport->hb_timer, jiffies + (HZ/20)))
  326. sctp_transport_hold(transport);
  327. goto out_unlock;
  328. }
  329. /* Is this structure just waiting around for us to actually
  330. * get destroyed?
  331. */
  332. if (transport->dead)
  333. goto out_unlock;
  334. error = sctp_do_sm(SCTP_EVENT_T_TIMEOUT,
  335. SCTP_ST_TIMEOUT(SCTP_EVENT_TIMEOUT_HEARTBEAT),
  336. asoc->state, asoc->ep, asoc,
  337. transport, GFP_ATOMIC);
  338. if (error)
  339. asoc->base.sk->sk_err = -error;
  340. out_unlock:
  341. sctp_bh_unlock_sock(asoc->base.sk);
  342. sctp_transport_put(transport);
  343. }
  344. /* Inject a SACK Timeout event into the state machine. */
  345. static void sctp_generate_sack_event(unsigned long data)
  346. {
  347. struct sctp_association *asoc = (struct sctp_association *) data;
  348. sctp_generate_timeout_event(asoc, SCTP_EVENT_TIMEOUT_SACK);
  349. }
  350. sctp_timer_event_t *sctp_timer_events[SCTP_NUM_TIMEOUT_TYPES] = {
  351. NULL,
  352. sctp_generate_t1_cookie_event,
  353. sctp_generate_t1_init_event,
  354. sctp_generate_t2_shutdown_event,
  355. NULL,
  356. sctp_generate_t4_rto_event,
  357. sctp_generate_t5_shutdown_guard_event,
  358. NULL,
  359. sctp_generate_sack_event,
  360. sctp_generate_autoclose_event,
  361. };
  362. /* RFC 2960 8.2 Path Failure Detection
  363. *
  364. * When its peer endpoint is multi-homed, an endpoint should keep a
  365. * error counter for each of the destination transport addresses of the
  366. * peer endpoint.
  367. *
  368. * Each time the T3-rtx timer expires on any address, or when a
  369. * HEARTBEAT sent to an idle address is not acknowledged within a RTO,
  370. * the error counter of that destination address will be incremented.
  371. * When the value in the error counter exceeds the protocol parameter
  372. * 'Path.Max.Retrans' of that destination address, the endpoint should
  373. * mark the destination transport address as inactive, and a
  374. * notification SHOULD be sent to the upper layer.
  375. *
  376. */
  377. static void sctp_do_8_2_transport_strike(struct sctp_association *asoc,
  378. struct sctp_transport *transport)
  379. {
  380. /* The check for association's overall error counter exceeding the
  381. * threshold is done in the state function.
  382. */
  383. /* When probing UNCONFIRMED addresses, the association overall
  384. * error count is NOT incremented
  385. */
  386. if (transport->state != SCTP_UNCONFIRMED)
  387. asoc->overall_error_count++;
  388. if (transport->state != SCTP_INACTIVE &&
  389. (transport->error_count++ >= transport->pathmaxrxt)) {
  390. SCTP_DEBUG_PRINTK_IPADDR("transport_strike:association %p",
  391. " transport IP: port:%d failed.\n",
  392. asoc,
  393. (&transport->ipaddr),
  394. ntohs(transport->ipaddr.v4.sin_port));
  395. sctp_assoc_control_transport(asoc, transport,
  396. SCTP_TRANSPORT_DOWN,
  397. SCTP_FAILED_THRESHOLD);
  398. }
  399. /* E2) For the destination address for which the timer
  400. * expires, set RTO <- RTO * 2 ("back off the timer"). The
  401. * maximum value discussed in rule C7 above (RTO.max) may be
  402. * used to provide an upper bound to this doubling operation.
  403. */
  404. transport->last_rto = transport->rto;
  405. transport->rto = min((transport->rto * 2), transport->asoc->rto_max);
  406. }
  407. /* Worker routine to handle INIT command failure. */
  408. static void sctp_cmd_init_failed(sctp_cmd_seq_t *commands,
  409. struct sctp_association *asoc,
  410. unsigned error)
  411. {
  412. struct sctp_ulpevent *event;
  413. event = sctp_ulpevent_make_assoc_change(asoc,0, SCTP_CANT_STR_ASSOC,
  414. (__u16)error, 0, 0, NULL,
  415. GFP_ATOMIC);
  416. if (event)
  417. sctp_add_cmd_sf(commands, SCTP_CMD_EVENT_ULP,
  418. SCTP_ULPEVENT(event));
  419. sctp_add_cmd_sf(commands, SCTP_CMD_NEW_STATE,
  420. SCTP_STATE(SCTP_STATE_CLOSED));
  421. /* SEND_FAILED sent later when cleaning up the association. */
  422. asoc->outqueue.error = error;
  423. sctp_add_cmd_sf(commands, SCTP_CMD_DELETE_TCB, SCTP_NULL());
  424. }
  425. /* Worker routine to handle SCTP_CMD_ASSOC_FAILED. */
  426. static void sctp_cmd_assoc_failed(sctp_cmd_seq_t *commands,
  427. struct sctp_association *asoc,
  428. sctp_event_t event_type,
  429. sctp_subtype_t subtype,
  430. struct sctp_chunk *chunk,
  431. unsigned error)
  432. {
  433. struct sctp_ulpevent *event;
  434. /* Cancel any partial delivery in progress. */
  435. sctp_ulpq_abort_pd(&asoc->ulpq, GFP_ATOMIC);
  436. if (event_type == SCTP_EVENT_T_CHUNK && subtype.chunk == SCTP_CID_ABORT)
  437. event = sctp_ulpevent_make_assoc_change(asoc, 0, SCTP_COMM_LOST,
  438. (__u16)error, 0, 0, chunk,
  439. GFP_ATOMIC);
  440. else
  441. event = sctp_ulpevent_make_assoc_change(asoc, 0, SCTP_COMM_LOST,
  442. (__u16)error, 0, 0, NULL,
  443. GFP_ATOMIC);
  444. if (event)
  445. sctp_add_cmd_sf(commands, SCTP_CMD_EVENT_ULP,
  446. SCTP_ULPEVENT(event));
  447. sctp_add_cmd_sf(commands, SCTP_CMD_NEW_STATE,
  448. SCTP_STATE(SCTP_STATE_CLOSED));
  449. /* SEND_FAILED sent later when cleaning up the association. */
  450. asoc->outqueue.error = error;
  451. sctp_add_cmd_sf(commands, SCTP_CMD_DELETE_TCB, SCTP_NULL());
  452. }
  453. /* Process an init chunk (may be real INIT/INIT-ACK or an embedded INIT
  454. * inside the cookie. In reality, this is only used for INIT-ACK processing
  455. * since all other cases use "temporary" associations and can do all
  456. * their work in statefuns directly.
  457. */
  458. static int sctp_cmd_process_init(sctp_cmd_seq_t *commands,
  459. struct sctp_association *asoc,
  460. struct sctp_chunk *chunk,
  461. sctp_init_chunk_t *peer_init,
  462. gfp_t gfp)
  463. {
  464. int error;
  465. /* We only process the init as a sideeffect in a single
  466. * case. This is when we process the INIT-ACK. If we
  467. * fail during INIT processing (due to malloc problems),
  468. * just return the error and stop processing the stack.
  469. */
  470. if (!sctp_process_init(asoc, chunk->chunk_hdr->type,
  471. sctp_source(chunk), peer_init, gfp))
  472. error = -ENOMEM;
  473. else
  474. error = 0;
  475. return error;
  476. }
  477. /* Helper function to break out starting up of heartbeat timers. */
  478. static void sctp_cmd_hb_timers_start(sctp_cmd_seq_t *cmds,
  479. struct sctp_association *asoc)
  480. {
  481. struct sctp_transport *t;
  482. /* Start a heartbeat timer for each transport on the association.
  483. * hold a reference on the transport to make sure none of
  484. * the needed data structures go away.
  485. */
  486. list_for_each_entry(t, &asoc->peer.transport_addr_list, transports) {
  487. if (!mod_timer(&t->hb_timer, sctp_transport_timeout(t)))
  488. sctp_transport_hold(t);
  489. }
  490. }
  491. static void sctp_cmd_hb_timers_stop(sctp_cmd_seq_t *cmds,
  492. struct sctp_association *asoc)
  493. {
  494. struct sctp_transport *t;
  495. /* Stop all heartbeat timers. */
  496. list_for_each_entry(t, &asoc->peer.transport_addr_list,
  497. transports) {
  498. if (del_timer(&t->hb_timer))
  499. sctp_transport_put(t);
  500. }
  501. }
  502. /* Helper function to stop any pending T3-RTX timers */
  503. static void sctp_cmd_t3_rtx_timers_stop(sctp_cmd_seq_t *cmds,
  504. struct sctp_association *asoc)
  505. {
  506. struct sctp_transport *t;
  507. list_for_each_entry(t, &asoc->peer.transport_addr_list,
  508. transports) {
  509. if (timer_pending(&t->T3_rtx_timer) &&
  510. del_timer(&t->T3_rtx_timer)) {
  511. sctp_transport_put(t);
  512. }
  513. }
  514. }
  515. /* Helper function to update the heartbeat timer. */
  516. static void sctp_cmd_hb_timer_update(sctp_cmd_seq_t *cmds,
  517. struct sctp_transport *t)
  518. {
  519. /* Update the heartbeat timer. */
  520. if (!mod_timer(&t->hb_timer, sctp_transport_timeout(t)))
  521. sctp_transport_hold(t);
  522. }
  523. /* Helper function to handle the reception of an HEARTBEAT ACK. */
  524. static void sctp_cmd_transport_on(sctp_cmd_seq_t *cmds,
  525. struct sctp_association *asoc,
  526. struct sctp_transport *t,
  527. struct sctp_chunk *chunk)
  528. {
  529. sctp_sender_hb_info_t *hbinfo;
  530. /* 8.3 Upon the receipt of the HEARTBEAT ACK, the sender of the
  531. * HEARTBEAT should clear the error counter of the destination
  532. * transport address to which the HEARTBEAT was sent.
  533. * The association's overall error count is also cleared.
  534. */
  535. t->error_count = 0;
  536. t->asoc->overall_error_count = 0;
  537. /* Mark the destination transport address as active if it is not so
  538. * marked.
  539. */
  540. if ((t->state == SCTP_INACTIVE) || (t->state == SCTP_UNCONFIRMED))
  541. sctp_assoc_control_transport(asoc, t, SCTP_TRANSPORT_UP,
  542. SCTP_HEARTBEAT_SUCCESS);
  543. /* The receiver of the HEARTBEAT ACK should also perform an
  544. * RTT measurement for that destination transport address
  545. * using the time value carried in the HEARTBEAT ACK chunk.
  546. * If the transport's rto_pending variable has been cleared,
  547. * it was most likely due to a retransmit. However, we want
  548. * to re-enable it to properly update the rto.
  549. */
  550. if (t->rto_pending == 0)
  551. t->rto_pending = 1;
  552. hbinfo = (sctp_sender_hb_info_t *) chunk->skb->data;
  553. sctp_transport_update_rto(t, (jiffies - hbinfo->sent_at));
  554. /* Update the heartbeat timer. */
  555. if (!mod_timer(&t->hb_timer, sctp_transport_timeout(t)))
  556. sctp_transport_hold(t);
  557. }
  558. /* Helper function to do a transport reset at the expiry of the hearbeat
  559. * timer.
  560. */
  561. static void sctp_cmd_transport_reset(sctp_cmd_seq_t *cmds,
  562. struct sctp_association *asoc,
  563. struct sctp_transport *t)
  564. {
  565. sctp_transport_lower_cwnd(t, SCTP_LOWER_CWND_INACTIVE);
  566. /* Mark one strike against a transport. */
  567. sctp_do_8_2_transport_strike(asoc, t);
  568. }
  569. /* Helper function to process the process SACK command. */
  570. static int sctp_cmd_process_sack(sctp_cmd_seq_t *cmds,
  571. struct sctp_association *asoc,
  572. struct sctp_sackhdr *sackh)
  573. {
  574. int err = 0;
  575. if (sctp_outq_sack(&asoc->outqueue, sackh)) {
  576. /* There are no more TSNs awaiting SACK. */
  577. err = sctp_do_sm(SCTP_EVENT_T_OTHER,
  578. SCTP_ST_OTHER(SCTP_EVENT_NO_PENDING_TSN),
  579. asoc->state, asoc->ep, asoc, NULL,
  580. GFP_ATOMIC);
  581. }
  582. return err;
  583. }
  584. /* Helper function to set the timeout value for T2-SHUTDOWN timer and to set
  585. * the transport for a shutdown chunk.
  586. */
  587. static void sctp_cmd_setup_t2(sctp_cmd_seq_t *cmds,
  588. struct sctp_association *asoc,
  589. struct sctp_chunk *chunk)
  590. {
  591. struct sctp_transport *t;
  592. t = sctp_assoc_choose_shutdown_transport(asoc);
  593. asoc->shutdown_last_sent_to = t;
  594. asoc->timeouts[SCTP_EVENT_TIMEOUT_T2_SHUTDOWN] = t->rto;
  595. chunk->transport = t;
  596. }
  597. /* Helper function to change the state of an association. */
  598. static void sctp_cmd_new_state(sctp_cmd_seq_t *cmds,
  599. struct sctp_association *asoc,
  600. sctp_state_t state)
  601. {
  602. struct sock *sk = asoc->base.sk;
  603. asoc->state = state;
  604. SCTP_DEBUG_PRINTK("sctp_cmd_new_state: asoc %p[%s]\n",
  605. asoc, sctp_state_tbl[state]);
  606. if (sctp_style(sk, TCP)) {
  607. /* Change the sk->sk_state of a TCP-style socket that has
  608. * sucessfully completed a connect() call.
  609. */
  610. if (sctp_state(asoc, ESTABLISHED) && sctp_sstate(sk, CLOSED))
  611. sk->sk_state = SCTP_SS_ESTABLISHED;
  612. /* Set the RCV_SHUTDOWN flag when a SHUTDOWN is received. */
  613. if (sctp_state(asoc, SHUTDOWN_RECEIVED) &&
  614. sctp_sstate(sk, ESTABLISHED))
  615. sk->sk_shutdown |= RCV_SHUTDOWN;
  616. }
  617. if (sctp_state(asoc, COOKIE_WAIT)) {
  618. /* Reset init timeouts since they may have been
  619. * increased due to timer expirations.
  620. */
  621. asoc->timeouts[SCTP_EVENT_TIMEOUT_T1_INIT] =
  622. asoc->rto_initial;
  623. asoc->timeouts[SCTP_EVENT_TIMEOUT_T1_COOKIE] =
  624. asoc->rto_initial;
  625. }
  626. if (sctp_state(asoc, ESTABLISHED) ||
  627. sctp_state(asoc, CLOSED) ||
  628. sctp_state(asoc, SHUTDOWN_RECEIVED)) {
  629. /* Wake up any processes waiting in the asoc's wait queue in
  630. * sctp_wait_for_connect() or sctp_wait_for_sndbuf().
  631. */
  632. if (waitqueue_active(&asoc->wait))
  633. wake_up_interruptible(&asoc->wait);
  634. /* Wake up any processes waiting in the sk's sleep queue of
  635. * a TCP-style or UDP-style peeled-off socket in
  636. * sctp_wait_for_accept() or sctp_wait_for_packet().
  637. * For a UDP-style socket, the waiters are woken up by the
  638. * notifications.
  639. */
  640. if (!sctp_style(sk, UDP))
  641. sk->sk_state_change(sk);
  642. }
  643. }
  644. /* Helper function to delete an association. */
  645. static void sctp_cmd_delete_tcb(sctp_cmd_seq_t *cmds,
  646. struct sctp_association *asoc)
  647. {
  648. struct sock *sk = asoc->base.sk;
  649. /* If it is a non-temporary association belonging to a TCP-style
  650. * listening socket that is not closed, do not free it so that accept()
  651. * can pick it up later.
  652. */
  653. if (sctp_style(sk, TCP) && sctp_sstate(sk, LISTENING) &&
  654. (!asoc->temp) && (sk->sk_shutdown != SHUTDOWN_MASK))
  655. return;
  656. sctp_unhash_established(asoc);
  657. sctp_association_free(asoc);
  658. }
  659. /*
  660. * ADDIP Section 4.1 ASCONF Chunk Procedures
  661. * A4) Start a T-4 RTO timer, using the RTO value of the selected
  662. * destination address (we use active path instead of primary path just
  663. * because primary path may be inactive.
  664. */
  665. static void sctp_cmd_setup_t4(sctp_cmd_seq_t *cmds,
  666. struct sctp_association *asoc,
  667. struct sctp_chunk *chunk)
  668. {
  669. struct sctp_transport *t;
  670. t = asoc->peer.active_path;
  671. asoc->timeouts[SCTP_EVENT_TIMEOUT_T4_RTO] = t->rto;
  672. chunk->transport = t;
  673. }
  674. /* Process an incoming Operation Error Chunk. */
  675. static void sctp_cmd_process_operr(sctp_cmd_seq_t *cmds,
  676. struct sctp_association *asoc,
  677. struct sctp_chunk *chunk)
  678. {
  679. struct sctp_operr_chunk *operr_chunk;
  680. struct sctp_errhdr *err_hdr;
  681. operr_chunk = (struct sctp_operr_chunk *)chunk->chunk_hdr;
  682. err_hdr = &operr_chunk->err_hdr;
  683. switch (err_hdr->cause) {
  684. case SCTP_ERROR_UNKNOWN_CHUNK:
  685. {
  686. struct sctp_chunkhdr *unk_chunk_hdr;
  687. unk_chunk_hdr = (struct sctp_chunkhdr *)err_hdr->variable;
  688. switch (unk_chunk_hdr->type) {
  689. /* ADDIP 4.1 A9) If the peer responds to an ASCONF with an
  690. * ERROR chunk reporting that it did not recognized the ASCONF
  691. * chunk type, the sender of the ASCONF MUST NOT send any
  692. * further ASCONF chunks and MUST stop its T-4 timer.
  693. */
  694. case SCTP_CID_ASCONF:
  695. asoc->peer.asconf_capable = 0;
  696. sctp_add_cmd_sf(cmds, SCTP_CMD_TIMER_STOP,
  697. SCTP_TO(SCTP_EVENT_TIMEOUT_T4_RTO));
  698. break;
  699. default:
  700. break;
  701. }
  702. break;
  703. }
  704. default:
  705. break;
  706. }
  707. }
  708. /* Process variable FWDTSN chunk information. */
  709. static void sctp_cmd_process_fwdtsn(struct sctp_ulpq *ulpq,
  710. struct sctp_chunk *chunk)
  711. {
  712. struct sctp_fwdtsn_skip *skip;
  713. /* Walk through all the skipped SSNs */
  714. sctp_walk_fwdtsn(skip, chunk) {
  715. sctp_ulpq_skip(ulpq, ntohs(skip->stream), ntohs(skip->ssn));
  716. }
  717. return;
  718. }
  719. /* Helper function to remove the association non-primary peer
  720. * transports.
  721. */
  722. static void sctp_cmd_del_non_primary(struct sctp_association *asoc)
  723. {
  724. struct sctp_transport *t;
  725. struct list_head *pos;
  726. struct list_head *temp;
  727. list_for_each_safe(pos, temp, &asoc->peer.transport_addr_list) {
  728. t = list_entry(pos, struct sctp_transport, transports);
  729. if (!sctp_cmp_addr_exact(&t->ipaddr,
  730. &asoc->peer.primary_addr)) {
  731. sctp_assoc_del_peer(asoc, &t->ipaddr);
  732. }
  733. }
  734. return;
  735. }
  736. /* Helper function to set sk_err on a 1-1 style socket. */
  737. static void sctp_cmd_set_sk_err(struct sctp_association *asoc, int error)
  738. {
  739. struct sock *sk = asoc->base.sk;
  740. if (!sctp_style(sk, UDP))
  741. sk->sk_err = error;
  742. }
  743. /* Helper function to generate an association change event */
  744. static void sctp_cmd_assoc_change(sctp_cmd_seq_t *commands,
  745. struct sctp_association *asoc,
  746. u8 state)
  747. {
  748. struct sctp_ulpevent *ev;
  749. ev = sctp_ulpevent_make_assoc_change(asoc, 0, state, 0,
  750. asoc->c.sinit_num_ostreams,
  751. asoc->c.sinit_max_instreams,
  752. NULL, GFP_ATOMIC);
  753. if (ev)
  754. sctp_ulpq_tail_event(&asoc->ulpq, ev);
  755. }
  756. /* Helper function to generate an adaptation indication event */
  757. static void sctp_cmd_adaptation_ind(sctp_cmd_seq_t *commands,
  758. struct sctp_association *asoc)
  759. {
  760. struct sctp_ulpevent *ev;
  761. ev = sctp_ulpevent_make_adaptation_indication(asoc, GFP_ATOMIC);
  762. if (ev)
  763. sctp_ulpq_tail_event(&asoc->ulpq, ev);
  764. }
  765. /* These three macros allow us to pull the debugging code out of the
  766. * main flow of sctp_do_sm() to keep attention focused on the real
  767. * functionality there.
  768. */
  769. #define DEBUG_PRE \
  770. SCTP_DEBUG_PRINTK("sctp_do_sm prefn: " \
  771. "ep %p, %s, %s, asoc %p[%s], %s\n", \
  772. ep, sctp_evttype_tbl[event_type], \
  773. (*debug_fn)(subtype), asoc, \
  774. sctp_state_tbl[state], state_fn->name)
  775. #define DEBUG_POST \
  776. SCTP_DEBUG_PRINTK("sctp_do_sm postfn: " \
  777. "asoc %p, status: %s\n", \
  778. asoc, sctp_status_tbl[status])
  779. #define DEBUG_POST_SFX \
  780. SCTP_DEBUG_PRINTK("sctp_do_sm post sfx: error %d, asoc %p[%s]\n", \
  781. error, asoc, \
  782. sctp_state_tbl[(asoc && sctp_id2assoc(ep->base.sk, \
  783. sctp_assoc2id(asoc)))?asoc->state:SCTP_STATE_CLOSED])
  784. /*
  785. * This is the master state machine processing function.
  786. *
  787. * If you want to understand all of lksctp, this is a
  788. * good place to start.
  789. */
  790. int sctp_do_sm(sctp_event_t event_type, sctp_subtype_t subtype,
  791. sctp_state_t state,
  792. struct sctp_endpoint *ep,
  793. struct sctp_association *asoc,
  794. void *event_arg,
  795. gfp_t gfp)
  796. {
  797. sctp_cmd_seq_t commands;
  798. const sctp_sm_table_entry_t *state_fn;
  799. sctp_disposition_t status;
  800. int error = 0;
  801. typedef const char *(printfn_t)(sctp_subtype_t);
  802. static printfn_t *table[] = {
  803. NULL, sctp_cname, sctp_tname, sctp_oname, sctp_pname,
  804. };
  805. printfn_t *debug_fn __attribute__ ((unused)) = table[event_type];
  806. /* Look up the state function, run it, and then process the
  807. * side effects. These three steps are the heart of lksctp.
  808. */
  809. state_fn = sctp_sm_lookup_event(event_type, state, subtype);
  810. sctp_init_cmd_seq(&commands);
  811. DEBUG_PRE;
  812. status = (*state_fn->fn)(ep, asoc, subtype, event_arg, &commands);
  813. DEBUG_POST;
  814. error = sctp_side_effects(event_type, subtype, state,
  815. ep, asoc, event_arg, status,
  816. &commands, gfp);
  817. DEBUG_POST_SFX;
  818. return error;
  819. }
  820. #undef DEBUG_PRE
  821. #undef DEBUG_POST
  822. /*****************************************************************
  823. * This the master state function side effect processing function.
  824. *****************************************************************/
  825. static int sctp_side_effects(sctp_event_t event_type, sctp_subtype_t subtype,
  826. sctp_state_t state,
  827. struct sctp_endpoint *ep,
  828. struct sctp_association *asoc,
  829. void *event_arg,
  830. sctp_disposition_t status,
  831. sctp_cmd_seq_t *commands,
  832. gfp_t gfp)
  833. {
  834. int error;
  835. /* FIXME - Most of the dispositions left today would be categorized
  836. * as "exceptional" dispositions. For those dispositions, it
  837. * may not be proper to run through any of the commands at all.
  838. * For example, the command interpreter might be run only with
  839. * disposition SCTP_DISPOSITION_CONSUME.
  840. */
  841. if (0 != (error = sctp_cmd_interpreter(event_type, subtype, state,
  842. ep, asoc,
  843. event_arg, status,
  844. commands, gfp)))
  845. goto bail;
  846. switch (status) {
  847. case SCTP_DISPOSITION_DISCARD:
  848. SCTP_DEBUG_PRINTK("Ignored sctp protocol event - state %d, "
  849. "event_type %d, event_id %d\n",
  850. state, event_type, subtype.chunk);
  851. break;
  852. case SCTP_DISPOSITION_NOMEM:
  853. /* We ran out of memory, so we need to discard this
  854. * packet.
  855. */
  856. /* BUG--we should now recover some memory, probably by
  857. * reneging...
  858. */
  859. error = -ENOMEM;
  860. break;
  861. case SCTP_DISPOSITION_DELETE_TCB:
  862. /* This should now be a command. */
  863. break;
  864. case SCTP_DISPOSITION_CONSUME:
  865. case SCTP_DISPOSITION_ABORT:
  866. /*
  867. * We should no longer have much work to do here as the
  868. * real work has been done as explicit commands above.
  869. */
  870. break;
  871. case SCTP_DISPOSITION_VIOLATION:
  872. if (net_ratelimit())
  873. printk(KERN_ERR "sctp protocol violation state %d "
  874. "chunkid %d\n", state, subtype.chunk);
  875. break;
  876. case SCTP_DISPOSITION_NOT_IMPL:
  877. printk(KERN_WARNING "sctp unimplemented feature in state %d, "
  878. "event_type %d, event_id %d\n",
  879. state, event_type, subtype.chunk);
  880. break;
  881. case SCTP_DISPOSITION_BUG:
  882. printk(KERN_ERR "sctp bug in state %d, "
  883. "event_type %d, event_id %d\n",
  884. state, event_type, subtype.chunk);
  885. BUG();
  886. break;
  887. default:
  888. printk(KERN_ERR "sctp impossible disposition %d "
  889. "in state %d, event_type %d, event_id %d\n",
  890. status, state, event_type, subtype.chunk);
  891. BUG();
  892. break;
  893. }
  894. bail:
  895. return error;
  896. }
  897. /********************************************************************
  898. * 2nd Level Abstractions
  899. ********************************************************************/
  900. /* This is the side-effect interpreter. */
  901. static int sctp_cmd_interpreter(sctp_event_t event_type,
  902. sctp_subtype_t subtype,
  903. sctp_state_t state,
  904. struct sctp_endpoint *ep,
  905. struct sctp_association *asoc,
  906. void *event_arg,
  907. sctp_disposition_t status,
  908. sctp_cmd_seq_t *commands,
  909. gfp_t gfp)
  910. {
  911. int error = 0;
  912. int force;
  913. sctp_cmd_t *cmd;
  914. struct sctp_chunk *new_obj;
  915. struct sctp_chunk *chunk = NULL;
  916. struct sctp_packet *packet;
  917. struct timer_list *timer;
  918. unsigned long timeout;
  919. struct sctp_transport *t;
  920. struct sctp_sackhdr sackh;
  921. int local_cork = 0;
  922. if (SCTP_EVENT_T_TIMEOUT != event_type)
  923. chunk = (struct sctp_chunk *) event_arg;
  924. /* Note: This whole file is a huge candidate for rework.
  925. * For example, each command could either have its own handler, so
  926. * the loop would look like:
  927. * while (cmds)
  928. * cmd->handle(x, y, z)
  929. * --jgrimm
  930. */
  931. while (NULL != (cmd = sctp_next_cmd(commands))) {
  932. switch (cmd->verb) {
  933. case SCTP_CMD_NOP:
  934. /* Do nothing. */
  935. break;
  936. case SCTP_CMD_NEW_ASOC:
  937. /* Register a new association. */
  938. if (local_cork) {
  939. sctp_outq_uncork(&asoc->outqueue);
  940. local_cork = 0;
  941. }
  942. asoc = cmd->obj.ptr;
  943. /* Register with the endpoint. */
  944. sctp_endpoint_add_asoc(ep, asoc);
  945. sctp_hash_established(asoc);
  946. break;
  947. case SCTP_CMD_UPDATE_ASSOC:
  948. sctp_assoc_update(asoc, cmd->obj.ptr);
  949. break;
  950. case SCTP_CMD_PURGE_OUTQUEUE:
  951. sctp_outq_teardown(&asoc->outqueue);
  952. break;
  953. case SCTP_CMD_DELETE_TCB:
  954. if (local_cork) {
  955. sctp_outq_uncork(&asoc->outqueue);
  956. local_cork = 0;
  957. }
  958. /* Delete the current association. */
  959. sctp_cmd_delete_tcb(commands, asoc);
  960. asoc = NULL;
  961. break;
  962. case SCTP_CMD_NEW_STATE:
  963. /* Enter a new state. */
  964. sctp_cmd_new_state(commands, asoc, cmd->obj.state);
  965. break;
  966. case SCTP_CMD_REPORT_TSN:
  967. /* Record the arrival of a TSN. */
  968. sctp_tsnmap_mark(&asoc->peer.tsn_map, cmd->obj.u32);
  969. break;
  970. case SCTP_CMD_REPORT_FWDTSN:
  971. /* Move the Cumulattive TSN Ack ahead. */
  972. sctp_tsnmap_skip(&asoc->peer.tsn_map, cmd->obj.u32);
  973. /* purge the fragmentation queue */
  974. sctp_ulpq_reasm_flushtsn(&asoc->ulpq, cmd->obj.u32);
  975. /* Abort any in progress partial delivery. */
  976. sctp_ulpq_abort_pd(&asoc->ulpq, GFP_ATOMIC);
  977. break;
  978. case SCTP_CMD_PROCESS_FWDTSN:
  979. sctp_cmd_process_fwdtsn(&asoc->ulpq, cmd->obj.ptr);
  980. break;
  981. case SCTP_CMD_GEN_SACK:
  982. /* Generate a Selective ACK.
  983. * The argument tells us whether to just count
  984. * the packet and MAYBE generate a SACK, or
  985. * force a SACK out.
  986. */
  987. force = cmd->obj.i32;
  988. error = sctp_gen_sack(asoc, force, commands);
  989. break;
  990. case SCTP_CMD_PROCESS_SACK:
  991. /* Process an inbound SACK. */
  992. error = sctp_cmd_process_sack(commands, asoc,
  993. cmd->obj.ptr);
  994. break;
  995. case SCTP_CMD_GEN_INIT_ACK:
  996. /* Generate an INIT ACK chunk. */
  997. new_obj = sctp_make_init_ack(asoc, chunk, GFP_ATOMIC,
  998. 0);
  999. if (!new_obj)
  1000. goto nomem;
  1001. sctp_add_cmd_sf(commands, SCTP_CMD_REPLY,
  1002. SCTP_CHUNK(new_obj));
  1003. break;
  1004. case SCTP_CMD_PEER_INIT:
  1005. /* Process a unified INIT from the peer.
  1006. * Note: Only used during INIT-ACK processing. If
  1007. * there is an error just return to the outter
  1008. * layer which will bail.
  1009. */
  1010. error = sctp_cmd_process_init(commands, asoc, chunk,
  1011. cmd->obj.ptr, gfp);
  1012. break;
  1013. case SCTP_CMD_GEN_COOKIE_ECHO:
  1014. /* Generate a COOKIE ECHO chunk. */
  1015. new_obj = sctp_make_cookie_echo(asoc, chunk);
  1016. if (!new_obj) {
  1017. if (cmd->obj.ptr)
  1018. sctp_chunk_free(cmd->obj.ptr);
  1019. goto nomem;
  1020. }
  1021. sctp_add_cmd_sf(commands, SCTP_CMD_REPLY,
  1022. SCTP_CHUNK(new_obj));
  1023. /* If there is an ERROR chunk to be sent along with
  1024. * the COOKIE_ECHO, send it, too.
  1025. */
  1026. if (cmd->obj.ptr)
  1027. sctp_add_cmd_sf(commands, SCTP_CMD_REPLY,
  1028. SCTP_CHUNK(cmd->obj.ptr));
  1029. /* FIXME - Eventually come up with a cleaner way to
  1030. * enabling COOKIE-ECHO + DATA bundling during
  1031. * multihoming stale cookie scenarios, the following
  1032. * command plays with asoc->peer.retran_path to
  1033. * avoid the problem of sending the COOKIE-ECHO and
  1034. * DATA in different paths, which could result
  1035. * in the association being ABORTed if the DATA chunk
  1036. * is processed first by the server. Checking the
  1037. * init error counter simply causes this command
  1038. * to be executed only during failed attempts of
  1039. * association establishment.
  1040. */
  1041. if ((asoc->peer.retran_path !=
  1042. asoc->peer.primary_path) &&
  1043. (asoc->init_err_counter > 0)) {
  1044. sctp_add_cmd_sf(commands,
  1045. SCTP_CMD_FORCE_PRIM_RETRAN,
  1046. SCTP_NULL());
  1047. }
  1048. break;
  1049. case SCTP_CMD_GEN_SHUTDOWN:
  1050. /* Generate SHUTDOWN when in SHUTDOWN_SENT state.
  1051. * Reset error counts.
  1052. */
  1053. asoc->overall_error_count = 0;
  1054. /* Generate a SHUTDOWN chunk. */
  1055. new_obj = sctp_make_shutdown(asoc, chunk);
  1056. if (!new_obj)
  1057. goto nomem;
  1058. sctp_add_cmd_sf(commands, SCTP_CMD_REPLY,
  1059. SCTP_CHUNK(new_obj));
  1060. break;
  1061. case SCTP_CMD_CHUNK_ULP:
  1062. /* Send a chunk to the sockets layer. */
  1063. SCTP_DEBUG_PRINTK("sm_sideff: %s %p, %s %p.\n",
  1064. "chunk_up:", cmd->obj.ptr,
  1065. "ulpq:", &asoc->ulpq);
  1066. sctp_ulpq_tail_data(&asoc->ulpq, cmd->obj.ptr,
  1067. GFP_ATOMIC);
  1068. break;
  1069. case SCTP_CMD_EVENT_ULP:
  1070. /* Send a notification to the sockets layer. */
  1071. SCTP_DEBUG_PRINTK("sm_sideff: %s %p, %s %p.\n",
  1072. "event_up:",cmd->obj.ptr,
  1073. "ulpq:",&asoc->ulpq);
  1074. sctp_ulpq_tail_event(&asoc->ulpq, cmd->obj.ptr);
  1075. break;
  1076. case SCTP_CMD_REPLY:
  1077. /* If an caller has not already corked, do cork. */
  1078. if (!asoc->outqueue.cork) {
  1079. sctp_outq_cork(&asoc->outqueue);
  1080. local_cork = 1;
  1081. }
  1082. /* Send a chunk to our peer. */
  1083. error = sctp_outq_tail(&asoc->outqueue, cmd->obj.ptr);
  1084. break;
  1085. case SCTP_CMD_SEND_PKT:
  1086. /* Send a full packet to our peer. */
  1087. packet = cmd->obj.ptr;
  1088. sctp_packet_transmit(packet);
  1089. sctp_ootb_pkt_free(packet);
  1090. break;
  1091. case SCTP_CMD_T1_RETRAN:
  1092. /* Mark a transport for retransmission. */
  1093. sctp_retransmit(&asoc->outqueue, cmd->obj.transport,
  1094. SCTP_RTXR_T1_RTX);
  1095. break;
  1096. case SCTP_CMD_RETRAN:
  1097. /* Mark a transport for retransmission. */
  1098. sctp_retransmit(&asoc->outqueue, cmd->obj.transport,
  1099. SCTP_RTXR_T3_RTX);
  1100. break;
  1101. case SCTP_CMD_TRANSMIT:
  1102. /* Kick start transmission. */
  1103. error = sctp_outq_uncork(&asoc->outqueue);
  1104. local_cork = 0;
  1105. break;
  1106. case SCTP_CMD_ECN_CE:
  1107. /* Do delayed CE processing. */
  1108. sctp_do_ecn_ce_work(asoc, cmd->obj.u32);
  1109. break;
  1110. case SCTP_CMD_ECN_ECNE:
  1111. /* Do delayed ECNE processing. */
  1112. new_obj = sctp_do_ecn_ecne_work(asoc, cmd->obj.u32,
  1113. chunk);
  1114. if (new_obj)
  1115. sctp_add_cmd_sf(commands, SCTP_CMD_REPLY,
  1116. SCTP_CHUNK(new_obj));
  1117. break;
  1118. case SCTP_CMD_ECN_CWR:
  1119. /* Do delayed CWR processing. */
  1120. sctp_do_ecn_cwr_work(asoc, cmd->obj.u32);
  1121. break;
  1122. case SCTP_CMD_SETUP_T2:
  1123. sctp_cmd_setup_t2(commands, asoc, cmd->obj.ptr);
  1124. break;
  1125. case SCTP_CMD_TIMER_START:
  1126. timer = &asoc->timers[cmd->obj.to];
  1127. timeout = asoc->timeouts[cmd->obj.to];
  1128. BUG_ON(!timeout);
  1129. timer->expires = jiffies + timeout;
  1130. sctp_association_hold(asoc);
  1131. add_timer(timer);
  1132. break;
  1133. case SCTP_CMD_TIMER_RESTART:
  1134. timer = &asoc->timers[cmd->obj.to];
  1135. timeout = asoc->timeouts[cmd->obj.to];
  1136. if (!mod_timer(timer, jiffies + timeout))
  1137. sctp_association_hold(asoc);
  1138. break;
  1139. case SCTP_CMD_TIMER_STOP:
  1140. timer = &asoc->timers[cmd->obj.to];
  1141. if (timer_pending(timer) && del_timer(timer))
  1142. sctp_association_put(asoc);
  1143. break;
  1144. case SCTP_CMD_INIT_CHOOSE_TRANSPORT:
  1145. chunk = cmd->obj.ptr;
  1146. t = sctp_assoc_choose_init_transport(asoc);
  1147. asoc->init_last_sent_to = t;
  1148. chunk->transport = t;
  1149. t->init_sent_count++;
  1150. break;
  1151. case SCTP_CMD_INIT_RESTART:
  1152. /* Do the needed accounting and updates
  1153. * associated with restarting an initialization
  1154. * timer. Only multiply the timeout by two if
  1155. * all transports have been tried at the current
  1156. * timeout.
  1157. */
  1158. t = asoc->init_last_sent_to;
  1159. asoc->init_err_counter++;
  1160. if (t->init_sent_count > (asoc->init_cycle + 1)) {
  1161. asoc->timeouts[SCTP_EVENT_TIMEOUT_T1_INIT] *= 2;
  1162. if (asoc->timeouts[SCTP_EVENT_TIMEOUT_T1_INIT] >
  1163. asoc->max_init_timeo) {
  1164. asoc->timeouts[SCTP_EVENT_TIMEOUT_T1_INIT] =
  1165. asoc->max_init_timeo;
  1166. }
  1167. asoc->init_cycle++;
  1168. SCTP_DEBUG_PRINTK(
  1169. "T1 INIT Timeout adjustment"
  1170. " init_err_counter: %d"
  1171. " cycle: %d"
  1172. " timeout: %ld\n",
  1173. asoc->init_err_counter,
  1174. asoc->init_cycle,
  1175. asoc->timeouts[SCTP_EVENT_TIMEOUT_T1_INIT]);
  1176. }
  1177. sctp_add_cmd_sf(commands, SCTP_CMD_TIMER_RESTART,
  1178. SCTP_TO(SCTP_EVENT_TIMEOUT_T1_INIT));
  1179. break;
  1180. case SCTP_CMD_COOKIEECHO_RESTART:
  1181. /* Do the needed accounting and updates
  1182. * associated with restarting an initialization
  1183. * timer. Only multiply the timeout by two if
  1184. * all transports have been tried at the current
  1185. * timeout.
  1186. */
  1187. asoc->init_err_counter++;
  1188. asoc->timeouts[SCTP_EVENT_TIMEOUT_T1_COOKIE] *= 2;
  1189. if (asoc->timeouts[SCTP_EVENT_TIMEOUT_T1_COOKIE] >
  1190. asoc->max_init_timeo) {
  1191. asoc->timeouts[SCTP_EVENT_TIMEOUT_T1_COOKIE] =
  1192. asoc->max_init_timeo;
  1193. }
  1194. SCTP_DEBUG_PRINTK(
  1195. "T1 COOKIE Timeout adjustment"
  1196. " init_err_counter: %d"
  1197. " timeout: %ld\n",
  1198. asoc->init_err_counter,
  1199. asoc->timeouts[SCTP_EVENT_TIMEOUT_T1_COOKIE]);
  1200. /* If we've sent any data bundled with
  1201. * COOKIE-ECHO we need to resend.
  1202. */
  1203. list_for_each_entry(t, &asoc->peer.transport_addr_list,
  1204. transports) {
  1205. sctp_retransmit_mark(&asoc->outqueue, t,
  1206. SCTP_RTXR_T1_RTX);
  1207. }
  1208. sctp_add_cmd_sf(commands,
  1209. SCTP_CMD_TIMER_RESTART,
  1210. SCTP_TO(SCTP_EVENT_TIMEOUT_T1_COOKIE));
  1211. break;
  1212. case SCTP_CMD_INIT_FAILED:
  1213. sctp_cmd_init_failed(commands, asoc, cmd->obj.err);
  1214. break;
  1215. case SCTP_CMD_ASSOC_FAILED:
  1216. sctp_cmd_assoc_failed(commands, asoc, event_type,
  1217. subtype, chunk, cmd->obj.err);
  1218. break;
  1219. case SCTP_CMD_INIT_COUNTER_INC:
  1220. asoc->init_err_counter++;
  1221. break;
  1222. case SCTP_CMD_INIT_COUNTER_RESET:
  1223. asoc->init_err_counter = 0;
  1224. asoc->init_cycle = 0;
  1225. break;
  1226. case SCTP_CMD_REPORT_DUP:
  1227. sctp_tsnmap_mark_dup(&asoc->peer.tsn_map,
  1228. cmd->obj.u32);
  1229. break;
  1230. case SCTP_CMD_REPORT_BAD_TAG:
  1231. SCTP_DEBUG_PRINTK("vtag mismatch!\n");
  1232. break;
  1233. case SCTP_CMD_STRIKE:
  1234. /* Mark one strike against a transport. */
  1235. sctp_do_8_2_transport_strike(asoc, cmd->obj.transport);
  1236. break;
  1237. case SCTP_CMD_TRANSPORT_RESET:
  1238. t = cmd->obj.transport;
  1239. sctp_cmd_transport_reset(commands, asoc, t);
  1240. break;
  1241. case SCTP_CMD_TRANSPORT_ON:
  1242. t = cmd->obj.transport;
  1243. sctp_cmd_transport_on(commands, asoc, t, chunk);
  1244. break;
  1245. case SCTP_CMD_HB_TIMERS_START:
  1246. sctp_cmd_hb_timers_start(commands, asoc);
  1247. break;
  1248. case SCTP_CMD_HB_TIMER_UPDATE:
  1249. t = cmd->obj.transport;
  1250. sctp_cmd_hb_timer_update(commands, t);
  1251. break;
  1252. case SCTP_CMD_HB_TIMERS_STOP:
  1253. sctp_cmd_hb_timers_stop(commands, asoc);
  1254. break;
  1255. case SCTP_CMD_REPORT_ERROR:
  1256. error = cmd->obj.error;
  1257. break;
  1258. case SCTP_CMD_PROCESS_CTSN:
  1259. /* Dummy up a SACK for processing. */
  1260. sackh.cum_tsn_ack = cmd->obj.be32;
  1261. sackh.a_rwnd = 0;
  1262. sackh.num_gap_ack_blocks = 0;
  1263. sackh.num_dup_tsns = 0;
  1264. sctp_add_cmd_sf(commands, SCTP_CMD_PROCESS_SACK,
  1265. SCTP_SACKH(&sackh));
  1266. break;
  1267. case SCTP_CMD_DISCARD_PACKET:
  1268. /* We need to discard the whole packet.
  1269. * Uncork the queue since there might be
  1270. * responses pending
  1271. */
  1272. chunk->pdiscard = 1;
  1273. if (asoc) {
  1274. sctp_outq_uncork(&asoc->outqueue);
  1275. local_cork = 0;
  1276. }
  1277. break;
  1278. case SCTP_CMD_RTO_PENDING:
  1279. t = cmd->obj.transport;
  1280. t->rto_pending = 1;
  1281. break;
  1282. case SCTP_CMD_PART_DELIVER:
  1283. sctp_ulpq_partial_delivery(&asoc->ulpq, cmd->obj.ptr,
  1284. GFP_ATOMIC);
  1285. break;
  1286. case SCTP_CMD_RENEGE:
  1287. sctp_ulpq_renege(&asoc->ulpq, cmd->obj.ptr,
  1288. GFP_ATOMIC);
  1289. break;
  1290. case SCTP_CMD_SETUP_T4:
  1291. sctp_cmd_setup_t4(commands, asoc, cmd->obj.ptr);
  1292. break;
  1293. case SCTP_CMD_PROCESS_OPERR:
  1294. sctp_cmd_process_operr(commands, asoc, chunk);
  1295. break;
  1296. case SCTP_CMD_CLEAR_INIT_TAG:
  1297. asoc->peer.i.init_tag = 0;
  1298. break;
  1299. case SCTP_CMD_DEL_NON_PRIMARY:
  1300. sctp_cmd_del_non_primary(asoc);
  1301. break;
  1302. case SCTP_CMD_T3_RTX_TIMERS_STOP:
  1303. sctp_cmd_t3_rtx_timers_stop(commands, asoc);
  1304. break;
  1305. case SCTP_CMD_FORCE_PRIM_RETRAN:
  1306. t = asoc->peer.retran_path;
  1307. asoc->peer.retran_path = asoc->peer.primary_path;
  1308. error = sctp_outq_uncork(&asoc->outqueue);
  1309. local_cork = 0;
  1310. asoc->peer.retran_path = t;
  1311. break;
  1312. case SCTP_CMD_SET_SK_ERR:
  1313. sctp_cmd_set_sk_err(asoc, cmd->obj.error);
  1314. break;
  1315. case SCTP_CMD_ASSOC_CHANGE:
  1316. sctp_cmd_assoc_change(commands, asoc,
  1317. cmd->obj.u8);
  1318. break;
  1319. case SCTP_CMD_ADAPTATION_IND:
  1320. sctp_cmd_adaptation_ind(commands, asoc);
  1321. break;
  1322. case SCTP_CMD_ASSOC_SHKEY:
  1323. error = sctp_auth_asoc_init_active_key(asoc,
  1324. GFP_ATOMIC);
  1325. break;
  1326. case SCTP_CMD_UPDATE_INITTAG:
  1327. asoc->peer.i.init_tag = cmd->obj.u32;
  1328. break;
  1329. default:
  1330. printk(KERN_WARNING "Impossible command: %u, %p\n",
  1331. cmd->verb, cmd->obj.ptr);
  1332. break;
  1333. }
  1334. if (error)
  1335. break;
  1336. }
  1337. out:
  1338. /* If this is in response to a received chunk, wait until
  1339. * we are done with the packet to open the queue so that we don't
  1340. * send multiple packets in response to a single request.
  1341. */
  1342. if (asoc && SCTP_EVENT_T_CHUNK == event_type && chunk) {
  1343. if (chunk->end_of_packet || chunk->singleton)
  1344. sctp_outq_uncork(&asoc->outqueue);
  1345. } else if (local_cork)
  1346. sctp_outq_uncork(&asoc->outqueue);
  1347. return error;
  1348. nomem:
  1349. error = -ENOMEM;
  1350. goto out;
  1351. }