1 /* SCTP kernel reference 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 reference 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 * The SCTP reference 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 * The SCTP reference 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 50 #include <linux/skbuff.h> 51 #include <linux/types.h> 52 #include <linux/socket.h> 53 #include <linux/ip.h> 54 #include <net/sock.h> 55 #include <net/sctp/sctp.h> 56 #include <net/sctp/sm.h> 57 58 static int sctp_cmd_interpreter(sctp_event_t event_type, 59 sctp_subtype_t subtype, 60 sctp_state_t state, 61 struct sctp_endpoint *ep, 62 struct sctp_association *asoc, 63 void *event_arg, 64 sctp_disposition_t status, 65 sctp_cmd_seq_t *commands, 66 gfp_t gfp); 67 static int sctp_side_effects(sctp_event_t event_type, sctp_subtype_t subtype, 68 sctp_state_t state, 69 struct sctp_endpoint *ep, 70 struct sctp_association *asoc, 71 void *event_arg, 72 sctp_disposition_t status, 73 sctp_cmd_seq_t *commands, 74 gfp_t gfp); 75 76 /******************************************************************** 77 * Helper functions 78 ********************************************************************/ 79 80 /* A helper function for delayed processing of INET ECN CE bit. */ 81 static void sctp_do_ecn_ce_work(struct sctp_association *asoc, 82 __u32 lowest_tsn) 83 { 84 /* Save the TSN away for comparison when we receive CWR */ 85 86 asoc->last_ecne_tsn = lowest_tsn; 87 asoc->need_ecne = 1; 88 } 89 90 /* Helper function for delayed processing of SCTP ECNE chunk. */ 91 /* RFC 2960 Appendix A 92 * 93 * RFC 2481 details a specific bit for a sender to send in 94 * the header of its next outbound TCP segment to indicate to 95 * its peer that it has reduced its congestion window. This 96 * is termed the CWR bit. For SCTP the same indication is made 97 * by including the CWR chunk. This chunk contains one data 98 * element, i.e. the TSN number that was sent in the ECNE chunk. 99 * This element represents the lowest TSN number in the datagram 100 * that was originally marked with the CE bit. 101 */ 102 static struct sctp_chunk *sctp_do_ecn_ecne_work(struct sctp_association *asoc, 103 __u32 lowest_tsn, 104 struct sctp_chunk *chunk) 105 { 106 struct sctp_chunk *repl; 107 108 /* Our previously transmitted packet ran into some congestion 109 * so we should take action by reducing cwnd and ssthresh 110 * and then ACK our peer that we we've done so by 111 * sending a CWR. 112 */ 113 114 /* First, try to determine if we want to actually lower 115 * our cwnd variables. Only lower them if the ECNE looks more 116 * recent than the last response. 117 */ 118 if (TSN_lt(asoc->last_cwr_tsn, lowest_tsn)) { 119 struct sctp_transport *transport; 120 121 /* Find which transport's congestion variables 122 * need to be adjusted. 123 */ 124 transport = sctp_assoc_lookup_tsn(asoc, lowest_tsn); 125 126 /* Update the congestion variables. */ 127 if (transport) 128 sctp_transport_lower_cwnd(transport, 129 SCTP_LOWER_CWND_ECNE); 130 asoc->last_cwr_tsn = lowest_tsn; 131 } 132 133 /* Always try to quiet the other end. In case of lost CWR, 134 * resend last_cwr_tsn. 135 */ 136 repl = sctp_make_cwr(asoc, asoc->last_cwr_tsn, chunk); 137 138 /* If we run out of memory, it will look like a lost CWR. We'll 139 * get back in sync eventually. 140 */ 141 return repl; 142 } 143 144 /* Helper function to do delayed processing of ECN CWR chunk. */ 145 static void sctp_do_ecn_cwr_work(struct sctp_association *asoc, 146 __u32 lowest_tsn) 147 { 148 /* Turn off ECNE getting auto-prepended to every outgoing 149 * packet 150 */ 151 asoc->need_ecne = 0; 152 } 153 154 /* Generate SACK if necessary. We call this at the end of a packet. */ 155 static int sctp_gen_sack(struct sctp_association *asoc, int force, 156 sctp_cmd_seq_t *commands) 157 { 158 __u32 ctsn, max_tsn_seen; 159 struct sctp_chunk *sack; 160 struct sctp_transport *trans = asoc->peer.last_data_from; 161 int error = 0; 162 163 if (force || 164 (!trans && (asoc->param_flags & SPP_SACKDELAY_DISABLE)) || 165 (trans && (trans->param_flags & SPP_SACKDELAY_DISABLE))) 166 asoc->peer.sack_needed = 1; 167 168 ctsn = sctp_tsnmap_get_ctsn(&asoc->peer.tsn_map); 169 max_tsn_seen = sctp_tsnmap_get_max_tsn_seen(&asoc->peer.tsn_map); 170 171 /* From 12.2 Parameters necessary per association (i.e. the TCB): 172 * 173 * Ack State : This flag indicates if the next received packet 174 * : is to be responded to with a SACK. ... 175 * : When DATA chunks are out of order, SACK's 176 * : are not delayed (see Section 6). 177 * 178 * [This is actually not mentioned in Section 6, but we 179 * implement it here anyway. --piggy] 180 */ 181 if (max_tsn_seen != ctsn) 182 asoc->peer.sack_needed = 1; 183 184 /* From 6.2 Acknowledgement on Reception of DATA Chunks: 185 * 186 * Section 4.2 of [RFC2581] SHOULD be followed. Specifically, 187 * an acknowledgement SHOULD be generated for at least every 188 * second packet (not every second DATA chunk) received, and 189 * SHOULD be generated within 200 ms of the arrival of any 190 * unacknowledged DATA chunk. ... 191 */ 192 if (!asoc->peer.sack_needed) { 193 /* We will need a SACK for the next packet. */ 194 asoc->peer.sack_needed = 1; 195 196 /* Set the SACK delay timeout based on the 197 * SACK delay for the last transport 198 * data was received from, or the default 199 * for the association. 200 */ 201 if (trans) 202 asoc->timeouts[SCTP_EVENT_TIMEOUT_SACK] = 203 trans->sackdelay; 204 else 205 asoc->timeouts[SCTP_EVENT_TIMEOUT_SACK] = 206 asoc->sackdelay; 207 208 /* Restart the SACK timer. */ 209 sctp_add_cmd_sf(commands, SCTP_CMD_TIMER_RESTART, 210 SCTP_TO(SCTP_EVENT_TIMEOUT_SACK)); 211 } else { 212 if (asoc->a_rwnd > asoc->rwnd) 213 asoc->a_rwnd = asoc->rwnd; 214 sack = sctp_make_sack(asoc); 215 if (!sack) 216 goto nomem; 217 218 asoc->peer.sack_needed = 0; 219 220 error = sctp_outq_tail(&asoc->outqueue, sack); 221 222 /* Stop the SACK timer. */ 223 sctp_add_cmd_sf(commands, SCTP_CMD_TIMER_STOP, 224 SCTP_TO(SCTP_EVENT_TIMEOUT_SACK)); 225 } 226 227 return error; 228 nomem: 229 error = -ENOMEM; 230 return error; 231 } 232 233 /* When the T3-RTX timer expires, it calls this function to create the 234 * relevant state machine event. 235 */ 236 void sctp_generate_t3_rtx_event(unsigned long peer) 237 { 238 int error; 239 struct sctp_transport *transport = (struct sctp_transport *) peer; 240 struct sctp_association *asoc = transport->asoc; 241 242 /* Check whether a task is in the sock. */ 243 244 sctp_bh_lock_sock(asoc->base.sk); 245 if (sock_owned_by_user(asoc->base.sk)) { 246 SCTP_DEBUG_PRINTK("%s:Sock is busy.\n", __FUNCTION__); 247 248 /* Try again later. */ 249 if (!mod_timer(&transport->T3_rtx_timer, jiffies + (HZ/20))) 250 sctp_transport_hold(transport); 251 goto out_unlock; 252 } 253 254 /* Is this transport really dead and just waiting around for 255 * the timer to let go of the reference? 256 */ 257 if (transport->dead) 258 goto out_unlock; 259 260 /* Run through the state machine. */ 261 error = sctp_do_sm(SCTP_EVENT_T_TIMEOUT, 262 SCTP_ST_TIMEOUT(SCTP_EVENT_TIMEOUT_T3_RTX), 263 asoc->state, 264 asoc->ep, asoc, 265 transport, GFP_ATOMIC); 266 267 if (error) 268 asoc->base.sk->sk_err = -error; 269 270 out_unlock: 271 sctp_bh_unlock_sock(asoc->base.sk); 272 sctp_transport_put(transport); 273 } 274 275 /* This is a sa interface for producing timeout events. It works 276 * for timeouts which use the association as their parameter. 277 */ 278 static void sctp_generate_timeout_event(struct sctp_association *asoc, 279 sctp_event_timeout_t timeout_type) 280 { 281 int error = 0; 282 283 sctp_bh_lock_sock(asoc->base.sk); 284 if (sock_owned_by_user(asoc->base.sk)) { 285 SCTP_DEBUG_PRINTK("%s:Sock is busy: timer %d\n", 286 __FUNCTION__, 287 timeout_type); 288 289 /* Try again later. */ 290 if (!mod_timer(&asoc->timers[timeout_type], jiffies + (HZ/20))) 291 sctp_association_hold(asoc); 292 goto out_unlock; 293 } 294 295 /* Is this association really dead and just waiting around for 296 * the timer to let go of the reference? 297 */ 298 if (asoc->base.dead) 299 goto out_unlock; 300 301 /* Run through the state machine. */ 302 error = sctp_do_sm(SCTP_EVENT_T_TIMEOUT, 303 SCTP_ST_TIMEOUT(timeout_type), 304 asoc->state, asoc->ep, asoc, 305 (void *)timeout_type, GFP_ATOMIC); 306 307 if (error) 308 asoc->base.sk->sk_err = -error; 309 310 out_unlock: 311 sctp_bh_unlock_sock(asoc->base.sk); 312 sctp_association_put(asoc); 313 } 314 315 static void sctp_generate_t1_cookie_event(unsigned long data) 316 { 317 struct sctp_association *asoc = (struct sctp_association *) data; 318 sctp_generate_timeout_event(asoc, SCTP_EVENT_TIMEOUT_T1_COOKIE); 319 } 320 321 static void sctp_generate_t1_init_event(unsigned long data) 322 { 323 struct sctp_association *asoc = (struct sctp_association *) data; 324 sctp_generate_timeout_event(asoc, SCTP_EVENT_TIMEOUT_T1_INIT); 325 } 326 327 static void sctp_generate_t2_shutdown_event(unsigned long data) 328 { 329 struct sctp_association *asoc = (struct sctp_association *) data; 330 sctp_generate_timeout_event(asoc, SCTP_EVENT_TIMEOUT_T2_SHUTDOWN); 331 } 332 333 static void sctp_generate_t4_rto_event(unsigned long data) 334 { 335 struct sctp_association *asoc = (struct sctp_association *) data; 336 sctp_generate_timeout_event(asoc, SCTP_EVENT_TIMEOUT_T4_RTO); 337 } 338 339 static void sctp_generate_t5_shutdown_guard_event(unsigned long data) 340 { 341 struct sctp_association *asoc = (struct sctp_association *)data; 342 sctp_generate_timeout_event(asoc, 343 SCTP_EVENT_TIMEOUT_T5_SHUTDOWN_GUARD); 344 345 } /* sctp_generate_t5_shutdown_guard_event() */ 346 347 static void sctp_generate_autoclose_event(unsigned long data) 348 { 349 struct sctp_association *asoc = (struct sctp_association *) data; 350 sctp_generate_timeout_event(asoc, SCTP_EVENT_TIMEOUT_AUTOCLOSE); 351 } 352 353 /* Generate a heart beat event. If the sock is busy, reschedule. Make 354 * sure that the transport is still valid. 355 */ 356 void sctp_generate_heartbeat_event(unsigned long data) 357 { 358 int error = 0; 359 struct sctp_transport *transport = (struct sctp_transport *) data; 360 struct sctp_association *asoc = transport->asoc; 361 362 sctp_bh_lock_sock(asoc->base.sk); 363 if (sock_owned_by_user(asoc->base.sk)) { 364 SCTP_DEBUG_PRINTK("%s:Sock is busy.\n", __FUNCTION__); 365 366 /* Try again later. */ 367 if (!mod_timer(&transport->hb_timer, jiffies + (HZ/20))) 368 sctp_transport_hold(transport); 369 goto out_unlock; 370 } 371 372 /* Is this structure just waiting around for us to actually 373 * get destroyed? 374 */ 375 if (transport->dead) 376 goto out_unlock; 377 378 error = sctp_do_sm(SCTP_EVENT_T_TIMEOUT, 379 SCTP_ST_TIMEOUT(SCTP_EVENT_TIMEOUT_HEARTBEAT), 380 asoc->state, asoc->ep, asoc, 381 transport, GFP_ATOMIC); 382 383 if (error) 384 asoc->base.sk->sk_err = -error; 385 386 out_unlock: 387 sctp_bh_unlock_sock(asoc->base.sk); 388 sctp_transport_put(transport); 389 } 390 391 /* Inject a SACK Timeout event into the state machine. */ 392 static void sctp_generate_sack_event(unsigned long data) 393 { 394 struct sctp_association *asoc = (struct sctp_association *) data; 395 sctp_generate_timeout_event(asoc, SCTP_EVENT_TIMEOUT_SACK); 396 } 397 398 sctp_timer_event_t *sctp_timer_events[SCTP_NUM_TIMEOUT_TYPES] = { 399 NULL, 400 sctp_generate_t1_cookie_event, 401 sctp_generate_t1_init_event, 402 sctp_generate_t2_shutdown_event, 403 NULL, 404 sctp_generate_t4_rto_event, 405 sctp_generate_t5_shutdown_guard_event, 406 NULL, 407 sctp_generate_sack_event, 408 sctp_generate_autoclose_event, 409 }; 410 411 412 /* RFC 2960 8.2 Path Failure Detection 413 * 414 * When its peer endpoint is multi-homed, an endpoint should keep a 415 * error counter for each of the destination transport addresses of the 416 * peer endpoint. 417 * 418 * Each time the T3-rtx timer expires on any address, or when a 419 * HEARTBEAT sent to an idle address is not acknowledged within a RTO, 420 * the error counter of that destination address will be incremented. 421 * When the value in the error counter exceeds the protocol parameter 422 * 'Path.Max.Retrans' of that destination address, the endpoint should 423 * mark the destination transport address as inactive, and a 424 * notification SHOULD be sent to the upper layer. 425 * 426 */ 427 static void sctp_do_8_2_transport_strike(struct sctp_association *asoc, 428 struct sctp_transport *transport) 429 { 430 /* The check for association's overall error counter exceeding the 431 * threshold is done in the state function. 432 */ 433 /* When probing UNCONFIRMED addresses, the association overall 434 * error count is NOT incremented 435 */ 436 if (transport->state != SCTP_UNCONFIRMED) 437 asoc->overall_error_count++; 438 439 if (transport->state != SCTP_INACTIVE && 440 (transport->error_count++ >= transport->pathmaxrxt)) { 441 SCTP_DEBUG_PRINTK_IPADDR("transport_strike:association %p", 442 " transport IP: port:%d failed.\n", 443 asoc, 444 (&transport->ipaddr), 445 transport->ipaddr.v4.sin_port); 446 sctp_assoc_control_transport(asoc, transport, 447 SCTP_TRANSPORT_DOWN, 448 SCTP_FAILED_THRESHOLD); 449 } 450 451 /* E2) For the destination address for which the timer 452 * expires, set RTO <- RTO * 2 ("back off the timer"). The 453 * maximum value discussed in rule C7 above (RTO.max) may be 454 * used to provide an upper bound to this doubling operation. 455 */ 456 transport->rto = min((transport->rto * 2), transport->asoc->rto_max); 457 } 458 459 /* Worker routine to handle INIT command failure. */ 460 static void sctp_cmd_init_failed(sctp_cmd_seq_t *commands, 461 struct sctp_association *asoc, 462 unsigned error) 463 { 464 struct sctp_ulpevent *event; 465 466 event = sctp_ulpevent_make_assoc_change(asoc,0, SCTP_CANT_STR_ASSOC, 467 (__u16)error, 0, 0, 468 GFP_ATOMIC); 469 470 if (event) 471 sctp_add_cmd_sf(commands, SCTP_CMD_EVENT_ULP, 472 SCTP_ULPEVENT(event)); 473 474 sctp_add_cmd_sf(commands, SCTP_CMD_NEW_STATE, 475 SCTP_STATE(SCTP_STATE_CLOSED)); 476 477 /* SEND_FAILED sent later when cleaning up the association. */ 478 asoc->outqueue.error = error; 479 sctp_add_cmd_sf(commands, SCTP_CMD_DELETE_TCB, SCTP_NULL()); 480 } 481 482 /* Worker routine to handle SCTP_CMD_ASSOC_FAILED. */ 483 static void sctp_cmd_assoc_failed(sctp_cmd_seq_t *commands, 484 struct sctp_association *asoc, 485 sctp_event_t event_type, 486 sctp_subtype_t subtype, 487 struct sctp_chunk *chunk, 488 unsigned error) 489 { 490 struct sctp_ulpevent *event; 491 492 /* Cancel any partial delivery in progress. */ 493 sctp_ulpq_abort_pd(&asoc->ulpq, GFP_ATOMIC); 494 495 event = sctp_ulpevent_make_assoc_change(asoc, 0, SCTP_COMM_LOST, 496 (__u16)error, 0, 0, 497 GFP_ATOMIC); 498 if (event) 499 sctp_add_cmd_sf(commands, SCTP_CMD_EVENT_ULP, 500 SCTP_ULPEVENT(event)); 501 502 sctp_add_cmd_sf(commands, SCTP_CMD_NEW_STATE, 503 SCTP_STATE(SCTP_STATE_CLOSED)); 504 505 /* SEND_FAILED sent later when cleaning up the association. */ 506 asoc->outqueue.error = error; 507 sctp_add_cmd_sf(commands, SCTP_CMD_DELETE_TCB, SCTP_NULL()); 508 } 509 510 /* Process an init chunk (may be real INIT/INIT-ACK or an embedded INIT 511 * inside the cookie. In reality, this is only used for INIT-ACK processing 512 * since all other cases use "temporary" associations and can do all 513 * their work in statefuns directly. 514 */ 515 static int sctp_cmd_process_init(sctp_cmd_seq_t *commands, 516 struct sctp_association *asoc, 517 struct sctp_chunk *chunk, 518 sctp_init_chunk_t *peer_init, 519 gfp_t gfp) 520 { 521 int error; 522 523 /* We only process the init as a sideeffect in a single 524 * case. This is when we process the INIT-ACK. If we 525 * fail during INIT processing (due to malloc problems), 526 * just return the error and stop processing the stack. 527 */ 528 if (!sctp_process_init(asoc, chunk->chunk_hdr->type, 529 sctp_source(chunk), peer_init, gfp)) 530 error = -ENOMEM; 531 else 532 error = 0; 533 534 return error; 535 } 536 537 /* Helper function to break out starting up of heartbeat timers. */ 538 static void sctp_cmd_hb_timers_start(sctp_cmd_seq_t *cmds, 539 struct sctp_association *asoc) 540 { 541 struct sctp_transport *t; 542 struct list_head *pos; 543 544 /* Start a heartbeat timer for each transport on the association. 545 * hold a reference on the transport to make sure none of 546 * the needed data structures go away. 547 */ 548 list_for_each(pos, &asoc->peer.transport_addr_list) { 549 t = list_entry(pos, struct sctp_transport, transports); 550 551 if (!mod_timer(&t->hb_timer, sctp_transport_timeout(t))) 552 sctp_transport_hold(t); 553 } 554 } 555 556 static void sctp_cmd_hb_timers_stop(sctp_cmd_seq_t *cmds, 557 struct sctp_association *asoc) 558 { 559 struct sctp_transport *t; 560 struct list_head *pos; 561 562 /* Stop all heartbeat timers. */ 563 564 list_for_each(pos, &asoc->peer.transport_addr_list) { 565 t = list_entry(pos, struct sctp_transport, transports); 566 if (del_timer(&t->hb_timer)) 567 sctp_transport_put(t); 568 } 569 } 570 571 /* Helper function to stop any pending T3-RTX timers */ 572 static void sctp_cmd_t3_rtx_timers_stop(sctp_cmd_seq_t *cmds, 573 struct sctp_association *asoc) 574 { 575 struct sctp_transport *t; 576 struct list_head *pos; 577 578 list_for_each(pos, &asoc->peer.transport_addr_list) { 579 t = list_entry(pos, struct sctp_transport, transports); 580 if (timer_pending(&t->T3_rtx_timer) && 581 del_timer(&t->T3_rtx_timer)) { 582 sctp_transport_put(t); 583 } 584 } 585 } 586 587 588 /* Helper function to update the heartbeat timer. */ 589 static void sctp_cmd_hb_timer_update(sctp_cmd_seq_t *cmds, 590 struct sctp_association *asoc, 591 struct sctp_transport *t) 592 { 593 /* Update the heartbeat timer. */ 594 if (!mod_timer(&t->hb_timer, sctp_transport_timeout(t))) 595 sctp_transport_hold(t); 596 } 597 598 /* Helper function to handle the reception of an HEARTBEAT ACK. */ 599 static void sctp_cmd_transport_on(sctp_cmd_seq_t *cmds, 600 struct sctp_association *asoc, 601 struct sctp_transport *t, 602 struct sctp_chunk *chunk) 603 { 604 sctp_sender_hb_info_t *hbinfo; 605 606 /* 8.3 Upon the receipt of the HEARTBEAT ACK, the sender of the 607 * HEARTBEAT should clear the error counter of the destination 608 * transport address to which the HEARTBEAT was sent. 609 * The association's overall error count is also cleared. 610 */ 611 t->error_count = 0; 612 t->asoc->overall_error_count = 0; 613 614 /* Mark the destination transport address as active if it is not so 615 * marked. 616 */ 617 if ((t->state == SCTP_INACTIVE) || (t->state == SCTP_UNCONFIRMED)) 618 sctp_assoc_control_transport(asoc, t, SCTP_TRANSPORT_UP, 619 SCTP_HEARTBEAT_SUCCESS); 620 621 /* The receiver of the HEARTBEAT ACK should also perform an 622 * RTT measurement for that destination transport address 623 * using the time value carried in the HEARTBEAT ACK chunk. 624 */ 625 hbinfo = (sctp_sender_hb_info_t *) chunk->skb->data; 626 sctp_transport_update_rto(t, (jiffies - hbinfo->sent_at)); 627 628 /* Update the heartbeat timer. */ 629 if (!mod_timer(&t->hb_timer, sctp_transport_timeout(t))) 630 sctp_transport_hold(t); 631 } 632 633 /* Helper function to do a transport reset at the expiry of the hearbeat 634 * timer. 635 */ 636 static void sctp_cmd_transport_reset(sctp_cmd_seq_t *cmds, 637 struct sctp_association *asoc, 638 struct sctp_transport *t) 639 { 640 sctp_transport_lower_cwnd(t, SCTP_LOWER_CWND_INACTIVE); 641 642 /* Mark one strike against a transport. */ 643 sctp_do_8_2_transport_strike(asoc, t); 644 } 645 646 /* Helper function to process the process SACK command. */ 647 static int sctp_cmd_process_sack(sctp_cmd_seq_t *cmds, 648 struct sctp_association *asoc, 649 struct sctp_sackhdr *sackh) 650 { 651 int err; 652 653 if (sctp_outq_sack(&asoc->outqueue, sackh)) { 654 /* There are no more TSNs awaiting SACK. */ 655 err = sctp_do_sm(SCTP_EVENT_T_OTHER, 656 SCTP_ST_OTHER(SCTP_EVENT_NO_PENDING_TSN), 657 asoc->state, asoc->ep, asoc, NULL, 658 GFP_ATOMIC); 659 } else { 660 /* Windows may have opened, so we need 661 * to check if we have DATA to transmit 662 */ 663 err = sctp_outq_flush(&asoc->outqueue, 0); 664 } 665 666 return err; 667 } 668 669 /* Helper function to set the timeout value for T2-SHUTDOWN timer and to set 670 * the transport for a shutdown chunk. 671 */ 672 static void sctp_cmd_setup_t2(sctp_cmd_seq_t *cmds, 673 struct sctp_association *asoc, 674 struct sctp_chunk *chunk) 675 { 676 struct sctp_transport *t; 677 678 t = sctp_assoc_choose_shutdown_transport(asoc); 679 asoc->shutdown_last_sent_to = t; 680 asoc->timeouts[SCTP_EVENT_TIMEOUT_T2_SHUTDOWN] = t->rto; 681 chunk->transport = t; 682 } 683 684 /* Helper function to change the state of an association. */ 685 static void sctp_cmd_new_state(sctp_cmd_seq_t *cmds, 686 struct sctp_association *asoc, 687 sctp_state_t state) 688 { 689 struct sock *sk = asoc->base.sk; 690 691 asoc->state = state; 692 693 SCTP_DEBUG_PRINTK("sctp_cmd_new_state: asoc %p[%s]\n", 694 asoc, sctp_state_tbl[state]); 695 696 if (sctp_style(sk, TCP)) { 697 /* Change the sk->sk_state of a TCP-style socket that has 698 * sucessfully completed a connect() call. 699 */ 700 if (sctp_state(asoc, ESTABLISHED) && sctp_sstate(sk, CLOSED)) 701 sk->sk_state = SCTP_SS_ESTABLISHED; 702 703 /* Set the RCV_SHUTDOWN flag when a SHUTDOWN is received. */ 704 if (sctp_state(asoc, SHUTDOWN_RECEIVED) && 705 sctp_sstate(sk, ESTABLISHED)) 706 sk->sk_shutdown |= RCV_SHUTDOWN; 707 } 708 709 if (sctp_state(asoc, COOKIE_WAIT)) { 710 /* Reset init timeouts since they may have been 711 * increased due to timer expirations. 712 */ 713 asoc->timeouts[SCTP_EVENT_TIMEOUT_T1_INIT] = 714 asoc->rto_initial; 715 asoc->timeouts[SCTP_EVENT_TIMEOUT_T1_COOKIE] = 716 asoc->rto_initial; 717 } 718 719 if (sctp_state(asoc, ESTABLISHED) || 720 sctp_state(asoc, CLOSED) || 721 sctp_state(asoc, SHUTDOWN_RECEIVED)) { 722 /* Wake up any processes waiting in the asoc's wait queue in 723 * sctp_wait_for_connect() or sctp_wait_for_sndbuf(). 724 */ 725 if (waitqueue_active(&asoc->wait)) 726 wake_up_interruptible(&asoc->wait); 727 728 /* Wake up any processes waiting in the sk's sleep queue of 729 * a TCP-style or UDP-style peeled-off socket in 730 * sctp_wait_for_accept() or sctp_wait_for_packet(). 731 * For a UDP-style socket, the waiters are woken up by the 732 * notifications. 733 */ 734 if (!sctp_style(sk, UDP)) 735 sk->sk_state_change(sk); 736 } 737 } 738 739 /* Helper function to delete an association. */ 740 static void sctp_cmd_delete_tcb(sctp_cmd_seq_t *cmds, 741 struct sctp_association *asoc) 742 { 743 struct sock *sk = asoc->base.sk; 744 745 /* If it is a non-temporary association belonging to a TCP-style 746 * listening socket that is not closed, do not free it so that accept() 747 * can pick it up later. 748 */ 749 if (sctp_style(sk, TCP) && sctp_sstate(sk, LISTENING) && 750 (!asoc->temp) && (sk->sk_shutdown != SHUTDOWN_MASK)) 751 return; 752 753 sctp_unhash_established(asoc); 754 sctp_association_free(asoc); 755 } 756 757 /* 758 * ADDIP Section 4.1 ASCONF Chunk Procedures 759 * A4) Start a T-4 RTO timer, using the RTO value of the selected 760 * destination address (we use active path instead of primary path just 761 * because primary path may be inactive. 762 */ 763 static void sctp_cmd_setup_t4(sctp_cmd_seq_t *cmds, 764 struct sctp_association *asoc, 765 struct sctp_chunk *chunk) 766 { 767 struct sctp_transport *t; 768 769 t = asoc->peer.active_path; 770 asoc->timeouts[SCTP_EVENT_TIMEOUT_T4_RTO] = t->rto; 771 chunk->transport = t; 772 } 773 774 /* Process an incoming Operation Error Chunk. */ 775 static void sctp_cmd_process_operr(sctp_cmd_seq_t *cmds, 776 struct sctp_association *asoc, 777 struct sctp_chunk *chunk) 778 { 779 struct sctp_operr_chunk *operr_chunk; 780 struct sctp_errhdr *err_hdr; 781 782 operr_chunk = (struct sctp_operr_chunk *)chunk->chunk_hdr; 783 err_hdr = &operr_chunk->err_hdr; 784 785 switch (err_hdr->cause) { 786 case SCTP_ERROR_UNKNOWN_CHUNK: 787 { 788 struct sctp_chunkhdr *unk_chunk_hdr; 789 790 unk_chunk_hdr = (struct sctp_chunkhdr *)err_hdr->variable; 791 switch (unk_chunk_hdr->type) { 792 /* ADDIP 4.1 A9) If the peer responds to an ASCONF with an 793 * ERROR chunk reporting that it did not recognized the ASCONF 794 * chunk type, the sender of the ASCONF MUST NOT send any 795 * further ASCONF chunks and MUST stop its T-4 timer. 796 */ 797 case SCTP_CID_ASCONF: 798 asoc->peer.asconf_capable = 0; 799 sctp_add_cmd_sf(cmds, SCTP_CMD_TIMER_STOP, 800 SCTP_TO(SCTP_EVENT_TIMEOUT_T4_RTO)); 801 break; 802 default: 803 break; 804 } 805 break; 806 } 807 default: 808 break; 809 } 810 } 811 812 /* Process variable FWDTSN chunk information. */ 813 static void sctp_cmd_process_fwdtsn(struct sctp_ulpq *ulpq, 814 struct sctp_chunk *chunk) 815 { 816 struct sctp_fwdtsn_skip *skip; 817 /* Walk through all the skipped SSNs */ 818 sctp_walk_fwdtsn(skip, chunk) { 819 sctp_ulpq_skip(ulpq, ntohs(skip->stream), ntohs(skip->ssn)); 820 } 821 822 return; 823 } 824 825 /* Helper function to remove the association non-primary peer 826 * transports. 827 */ 828 static void sctp_cmd_del_non_primary(struct sctp_association *asoc) 829 { 830 struct sctp_transport *t; 831 struct list_head *pos; 832 struct list_head *temp; 833 834 list_for_each_safe(pos, temp, &asoc->peer.transport_addr_list) { 835 t = list_entry(pos, struct sctp_transport, transports); 836 if (!sctp_cmp_addr_exact(&t->ipaddr, 837 &asoc->peer.primary_addr)) { 838 sctp_assoc_del_peer(asoc, &t->ipaddr); 839 } 840 } 841 842 return; 843 } 844 845 /* Helper function to set sk_err on a 1-1 style socket. */ 846 static void sctp_cmd_set_sk_err(struct sctp_association *asoc, int error) 847 { 848 struct sock *sk = asoc->base.sk; 849 850 if (!sctp_style(sk, UDP)) 851 sk->sk_err = error; 852 } 853 854 /* These three macros allow us to pull the debugging code out of the 855 * main flow of sctp_do_sm() to keep attention focused on the real 856 * functionality there. 857 */ 858 #define DEBUG_PRE \ 859 SCTP_DEBUG_PRINTK("sctp_do_sm prefn: " \ 860 "ep %p, %s, %s, asoc %p[%s], %s\n", \ 861 ep, sctp_evttype_tbl[event_type], \ 862 (*debug_fn)(subtype), asoc, \ 863 sctp_state_tbl[state], state_fn->name) 864 865 #define DEBUG_POST \ 866 SCTP_DEBUG_PRINTK("sctp_do_sm postfn: " \ 867 "asoc %p, status: %s\n", \ 868 asoc, sctp_status_tbl[status]) 869 870 #define DEBUG_POST_SFX \ 871 SCTP_DEBUG_PRINTK("sctp_do_sm post sfx: error %d, asoc %p[%s]\n", \ 872 error, asoc, \ 873 sctp_state_tbl[(asoc && sctp_id2assoc(ep->base.sk, \ 874 sctp_assoc2id(asoc)))?asoc->state:SCTP_STATE_CLOSED]) 875 876 /* 877 * This is the master state machine processing function. 878 * 879 * If you want to understand all of lksctp, this is a 880 * good place to start. 881 */ 882 int sctp_do_sm(sctp_event_t event_type, sctp_subtype_t subtype, 883 sctp_state_t state, 884 struct sctp_endpoint *ep, 885 struct sctp_association *asoc, 886 void *event_arg, 887 gfp_t gfp) 888 { 889 sctp_cmd_seq_t commands; 890 const sctp_sm_table_entry_t *state_fn; 891 sctp_disposition_t status; 892 int error = 0; 893 typedef const char *(printfn_t)(sctp_subtype_t); 894 895 static printfn_t *table[] = { 896 NULL, sctp_cname, sctp_tname, sctp_oname, sctp_pname, 897 }; 898 printfn_t *debug_fn __attribute__ ((unused)) = table[event_type]; 899 900 /* Look up the state function, run it, and then process the 901 * side effects. These three steps are the heart of lksctp. 902 */ 903 state_fn = sctp_sm_lookup_event(event_type, state, subtype); 904 905 sctp_init_cmd_seq(&commands); 906 907 DEBUG_PRE; 908 status = (*state_fn->fn)(ep, asoc, subtype, event_arg, &commands); 909 DEBUG_POST; 910 911 error = sctp_side_effects(event_type, subtype, state, 912 ep, asoc, event_arg, status, 913 &commands, gfp); 914 DEBUG_POST_SFX; 915 916 return error; 917 } 918 919 #undef DEBUG_PRE 920 #undef DEBUG_POST 921 922 /***************************************************************** 923 * This the master state function side effect processing function. 924 *****************************************************************/ 925 static int sctp_side_effects(sctp_event_t event_type, sctp_subtype_t subtype, 926 sctp_state_t state, 927 struct sctp_endpoint *ep, 928 struct sctp_association *asoc, 929 void *event_arg, 930 sctp_disposition_t status, 931 sctp_cmd_seq_t *commands, 932 gfp_t gfp) 933 { 934 int error; 935 936 /* FIXME - Most of the dispositions left today would be categorized 937 * as "exceptional" dispositions. For those dispositions, it 938 * may not be proper to run through any of the commands at all. 939 * For example, the command interpreter might be run only with 940 * disposition SCTP_DISPOSITION_CONSUME. 941 */ 942 if (0 != (error = sctp_cmd_interpreter(event_type, subtype, state, 943 ep, asoc, 944 event_arg, status, 945 commands, gfp))) 946 goto bail; 947 948 switch (status) { 949 case SCTP_DISPOSITION_DISCARD: 950 SCTP_DEBUG_PRINTK("Ignored sctp protocol event - state %d, " 951 "event_type %d, event_id %d\n", 952 state, event_type, subtype.chunk); 953 break; 954 955 case SCTP_DISPOSITION_NOMEM: 956 /* We ran out of memory, so we need to discard this 957 * packet. 958 */ 959 /* BUG--we should now recover some memory, probably by 960 * reneging... 961 */ 962 error = -ENOMEM; 963 break; 964 965 case SCTP_DISPOSITION_DELETE_TCB: 966 /* This should now be a command. */ 967 break; 968 969 case SCTP_DISPOSITION_CONSUME: 970 case SCTP_DISPOSITION_ABORT: 971 /* 972 * We should no longer have much work to do here as the 973 * real work has been done as explicit commands above. 974 */ 975 break; 976 977 case SCTP_DISPOSITION_VIOLATION: 978 printk(KERN_ERR "sctp protocol violation state %d " 979 "chunkid %d\n", state, subtype.chunk); 980 break; 981 982 case SCTP_DISPOSITION_NOT_IMPL: 983 printk(KERN_WARNING "sctp unimplemented feature in state %d, " 984 "event_type %d, event_id %d\n", 985 state, event_type, subtype.chunk); 986 break; 987 988 case SCTP_DISPOSITION_BUG: 989 printk(KERN_ERR "sctp bug in state %d, " 990 "event_type %d, event_id %d\n", 991 state, event_type, subtype.chunk); 992 BUG(); 993 break; 994 995 default: 996 printk(KERN_ERR "sctp impossible disposition %d " 997 "in state %d, event_type %d, event_id %d\n", 998 status, state, event_type, subtype.chunk); 999 BUG(); 1000 break; 1001 }; 1002 1003 bail: 1004 return error; 1005 } 1006 1007 /******************************************************************** 1008 * 2nd Level Abstractions 1009 ********************************************************************/ 1010 1011 /* This is the side-effect interpreter. */ 1012 static int sctp_cmd_interpreter(sctp_event_t event_type, 1013 sctp_subtype_t subtype, 1014 sctp_state_t state, 1015 struct sctp_endpoint *ep, 1016 struct sctp_association *asoc, 1017 void *event_arg, 1018 sctp_disposition_t status, 1019 sctp_cmd_seq_t *commands, 1020 gfp_t gfp) 1021 { 1022 int error = 0; 1023 int force; 1024 sctp_cmd_t *cmd; 1025 struct sctp_chunk *new_obj; 1026 struct sctp_chunk *chunk = NULL; 1027 struct sctp_packet *packet; 1028 struct list_head *pos; 1029 struct timer_list *timer; 1030 unsigned long timeout; 1031 struct sctp_transport *t; 1032 struct sctp_sackhdr sackh; 1033 int local_cork = 0; 1034 1035 if (SCTP_EVENT_T_TIMEOUT != event_type) 1036 chunk = (struct sctp_chunk *) event_arg; 1037 1038 /* Note: This whole file is a huge candidate for rework. 1039 * For example, each command could either have its own handler, so 1040 * the loop would look like: 1041 * while (cmds) 1042 * cmd->handle(x, y, z) 1043 * --jgrimm 1044 */ 1045 while (NULL != (cmd = sctp_next_cmd(commands))) { 1046 switch (cmd->verb) { 1047 case SCTP_CMD_NOP: 1048 /* Do nothing. */ 1049 break; 1050 1051 case SCTP_CMD_NEW_ASOC: 1052 /* Register a new association. */ 1053 if (local_cork) { 1054 sctp_outq_uncork(&asoc->outqueue); 1055 local_cork = 0; 1056 } 1057 asoc = cmd->obj.ptr; 1058 /* Register with the endpoint. */ 1059 sctp_endpoint_add_asoc(ep, asoc); 1060 sctp_hash_established(asoc); 1061 break; 1062 1063 case SCTP_CMD_UPDATE_ASSOC: 1064 sctp_assoc_update(asoc, cmd->obj.ptr); 1065 break; 1066 1067 case SCTP_CMD_PURGE_OUTQUEUE: 1068 sctp_outq_teardown(&asoc->outqueue); 1069 break; 1070 1071 case SCTP_CMD_DELETE_TCB: 1072 if (local_cork) { 1073 sctp_outq_uncork(&asoc->outqueue); 1074 local_cork = 0; 1075 } 1076 /* Delete the current association. */ 1077 sctp_cmd_delete_tcb(commands, asoc); 1078 asoc = NULL; 1079 break; 1080 1081 case SCTP_CMD_NEW_STATE: 1082 /* Enter a new state. */ 1083 sctp_cmd_new_state(commands, asoc, cmd->obj.state); 1084 break; 1085 1086 case SCTP_CMD_REPORT_TSN: 1087 /* Record the arrival of a TSN. */ 1088 sctp_tsnmap_mark(&asoc->peer.tsn_map, cmd->obj.u32); 1089 break; 1090 1091 case SCTP_CMD_REPORT_FWDTSN: 1092 /* Move the Cumulattive TSN Ack ahead. */ 1093 sctp_tsnmap_skip(&asoc->peer.tsn_map, cmd->obj.u32); 1094 1095 /* Abort any in progress partial delivery. */ 1096 sctp_ulpq_abort_pd(&asoc->ulpq, GFP_ATOMIC); 1097 break; 1098 1099 case SCTP_CMD_PROCESS_FWDTSN: 1100 sctp_cmd_process_fwdtsn(&asoc->ulpq, cmd->obj.ptr); 1101 break; 1102 1103 case SCTP_CMD_GEN_SACK: 1104 /* Generate a Selective ACK. 1105 * The argument tells us whether to just count 1106 * the packet and MAYBE generate a SACK, or 1107 * force a SACK out. 1108 */ 1109 force = cmd->obj.i32; 1110 error = sctp_gen_sack(asoc, force, commands); 1111 break; 1112 1113 case SCTP_CMD_PROCESS_SACK: 1114 /* Process an inbound SACK. */ 1115 error = sctp_cmd_process_sack(commands, asoc, 1116 cmd->obj.ptr); 1117 break; 1118 1119 case SCTP_CMD_GEN_INIT_ACK: 1120 /* Generate an INIT ACK chunk. */ 1121 new_obj = sctp_make_init_ack(asoc, chunk, GFP_ATOMIC, 1122 0); 1123 if (!new_obj) 1124 goto nomem; 1125 1126 sctp_add_cmd_sf(commands, SCTP_CMD_REPLY, 1127 SCTP_CHUNK(new_obj)); 1128 break; 1129 1130 case SCTP_CMD_PEER_INIT: 1131 /* Process a unified INIT from the peer. 1132 * Note: Only used during INIT-ACK processing. If 1133 * there is an error just return to the outter 1134 * layer which will bail. 1135 */ 1136 error = sctp_cmd_process_init(commands, asoc, chunk, 1137 cmd->obj.ptr, gfp); 1138 break; 1139 1140 case SCTP_CMD_GEN_COOKIE_ECHO: 1141 /* Generate a COOKIE ECHO chunk. */ 1142 new_obj = sctp_make_cookie_echo(asoc, chunk); 1143 if (!new_obj) { 1144 if (cmd->obj.ptr) 1145 sctp_chunk_free(cmd->obj.ptr); 1146 goto nomem; 1147 } 1148 sctp_add_cmd_sf(commands, SCTP_CMD_REPLY, 1149 SCTP_CHUNK(new_obj)); 1150 1151 /* If there is an ERROR chunk to be sent along with 1152 * the COOKIE_ECHO, send it, too. 1153 */ 1154 if (cmd->obj.ptr) 1155 sctp_add_cmd_sf(commands, SCTP_CMD_REPLY, 1156 SCTP_CHUNK(cmd->obj.ptr)); 1157 1158 /* FIXME - Eventually come up with a cleaner way to 1159 * enabling COOKIE-ECHO + DATA bundling during 1160 * multihoming stale cookie scenarios, the following 1161 * command plays with asoc->peer.retran_path to 1162 * avoid the problem of sending the COOKIE-ECHO and 1163 * DATA in different paths, which could result 1164 * in the association being ABORTed if the DATA chunk 1165 * is processed first by the server. Checking the 1166 * init error counter simply causes this command 1167 * to be executed only during failed attempts of 1168 * association establishment. 1169 */ 1170 if ((asoc->peer.retran_path != 1171 asoc->peer.primary_path) && 1172 (asoc->init_err_counter > 0)) { 1173 sctp_add_cmd_sf(commands, 1174 SCTP_CMD_FORCE_PRIM_RETRAN, 1175 SCTP_NULL()); 1176 } 1177 1178 break; 1179 1180 case SCTP_CMD_GEN_SHUTDOWN: 1181 /* Generate SHUTDOWN when in SHUTDOWN_SENT state. 1182 * Reset error counts. 1183 */ 1184 asoc->overall_error_count = 0; 1185 1186 /* Generate a SHUTDOWN chunk. */ 1187 new_obj = sctp_make_shutdown(asoc, chunk); 1188 if (!new_obj) 1189 goto nomem; 1190 sctp_add_cmd_sf(commands, SCTP_CMD_REPLY, 1191 SCTP_CHUNK(new_obj)); 1192 break; 1193 1194 case SCTP_CMD_CHUNK_ULP: 1195 /* Send a chunk to the sockets layer. */ 1196 SCTP_DEBUG_PRINTK("sm_sideff: %s %p, %s %p.\n", 1197 "chunk_up:", cmd->obj.ptr, 1198 "ulpq:", &asoc->ulpq); 1199 sctp_ulpq_tail_data(&asoc->ulpq, cmd->obj.ptr, 1200 GFP_ATOMIC); 1201 break; 1202 1203 case SCTP_CMD_EVENT_ULP: 1204 /* Send a notification to the sockets layer. */ 1205 SCTP_DEBUG_PRINTK("sm_sideff: %s %p, %s %p.\n", 1206 "event_up:",cmd->obj.ptr, 1207 "ulpq:",&asoc->ulpq); 1208 sctp_ulpq_tail_event(&asoc->ulpq, cmd->obj.ptr); 1209 break; 1210 1211 case SCTP_CMD_REPLY: 1212 /* If an caller has not already corked, do cork. */ 1213 if (!asoc->outqueue.cork) { 1214 sctp_outq_cork(&asoc->outqueue); 1215 local_cork = 1; 1216 } 1217 /* Send a chunk to our peer. */ 1218 error = sctp_outq_tail(&asoc->outqueue, cmd->obj.ptr); 1219 break; 1220 1221 case SCTP_CMD_SEND_PKT: 1222 /* Send a full packet to our peer. */ 1223 packet = cmd->obj.ptr; 1224 sctp_packet_transmit(packet); 1225 sctp_ootb_pkt_free(packet); 1226 break; 1227 1228 case SCTP_CMD_RETRAN: 1229 /* Mark a transport for retransmission. */ 1230 sctp_retransmit(&asoc->outqueue, cmd->obj.transport, 1231 SCTP_RTXR_T3_RTX); 1232 break; 1233 1234 case SCTP_CMD_TRANSMIT: 1235 /* Kick start transmission. */ 1236 error = sctp_outq_uncork(&asoc->outqueue); 1237 local_cork = 0; 1238 break; 1239 1240 case SCTP_CMD_ECN_CE: 1241 /* Do delayed CE processing. */ 1242 sctp_do_ecn_ce_work(asoc, cmd->obj.u32); 1243 break; 1244 1245 case SCTP_CMD_ECN_ECNE: 1246 /* Do delayed ECNE processing. */ 1247 new_obj = sctp_do_ecn_ecne_work(asoc, cmd->obj.u32, 1248 chunk); 1249 if (new_obj) 1250 sctp_add_cmd_sf(commands, SCTP_CMD_REPLY, 1251 SCTP_CHUNK(new_obj)); 1252 break; 1253 1254 case SCTP_CMD_ECN_CWR: 1255 /* Do delayed CWR processing. */ 1256 sctp_do_ecn_cwr_work(asoc, cmd->obj.u32); 1257 break; 1258 1259 case SCTP_CMD_SETUP_T2: 1260 sctp_cmd_setup_t2(commands, asoc, cmd->obj.ptr); 1261 break; 1262 1263 case SCTP_CMD_TIMER_START: 1264 timer = &asoc->timers[cmd->obj.to]; 1265 timeout = asoc->timeouts[cmd->obj.to]; 1266 BUG_ON(!timeout); 1267 1268 timer->expires = jiffies + timeout; 1269 sctp_association_hold(asoc); 1270 add_timer(timer); 1271 break; 1272 1273 case SCTP_CMD_TIMER_RESTART: 1274 timer = &asoc->timers[cmd->obj.to]; 1275 timeout = asoc->timeouts[cmd->obj.to]; 1276 if (!mod_timer(timer, jiffies + timeout)) 1277 sctp_association_hold(asoc); 1278 break; 1279 1280 case SCTP_CMD_TIMER_STOP: 1281 timer = &asoc->timers[cmd->obj.to]; 1282 if (timer_pending(timer) && del_timer(timer)) 1283 sctp_association_put(asoc); 1284 break; 1285 1286 case SCTP_CMD_INIT_CHOOSE_TRANSPORT: 1287 chunk = cmd->obj.ptr; 1288 t = sctp_assoc_choose_init_transport(asoc); 1289 asoc->init_last_sent_to = t; 1290 chunk->transport = t; 1291 t->init_sent_count++; 1292 break; 1293 1294 case SCTP_CMD_INIT_RESTART: 1295 /* Do the needed accounting and updates 1296 * associated with restarting an initialization 1297 * timer. Only multiply the timeout by two if 1298 * all transports have been tried at the current 1299 * timeout. 1300 */ 1301 t = asoc->init_last_sent_to; 1302 asoc->init_err_counter++; 1303 1304 if (t->init_sent_count > (asoc->init_cycle + 1)) { 1305 asoc->timeouts[SCTP_EVENT_TIMEOUT_T1_INIT] *= 2; 1306 if (asoc->timeouts[SCTP_EVENT_TIMEOUT_T1_INIT] > 1307 asoc->max_init_timeo) { 1308 asoc->timeouts[SCTP_EVENT_TIMEOUT_T1_INIT] = 1309 asoc->max_init_timeo; 1310 } 1311 asoc->init_cycle++; 1312 SCTP_DEBUG_PRINTK( 1313 "T1 INIT Timeout adjustment" 1314 " init_err_counter: %d" 1315 " cycle: %d" 1316 " timeout: %ld\n", 1317 asoc->init_err_counter, 1318 asoc->init_cycle, 1319 asoc->timeouts[SCTP_EVENT_TIMEOUT_T1_INIT]); 1320 } 1321 1322 sctp_add_cmd_sf(commands, SCTP_CMD_TIMER_RESTART, 1323 SCTP_TO(SCTP_EVENT_TIMEOUT_T1_INIT)); 1324 break; 1325 1326 case SCTP_CMD_COOKIEECHO_RESTART: 1327 /* Do the needed accounting and updates 1328 * associated with restarting an initialization 1329 * timer. Only multiply the timeout by two if 1330 * all transports have been tried at the current 1331 * timeout. 1332 */ 1333 asoc->init_err_counter++; 1334 1335 asoc->timeouts[SCTP_EVENT_TIMEOUT_T1_COOKIE] *= 2; 1336 if (asoc->timeouts[SCTP_EVENT_TIMEOUT_T1_COOKIE] > 1337 asoc->max_init_timeo) { 1338 asoc->timeouts[SCTP_EVENT_TIMEOUT_T1_COOKIE] = 1339 asoc->max_init_timeo; 1340 } 1341 SCTP_DEBUG_PRINTK( 1342 "T1 COOKIE Timeout adjustment" 1343 " init_err_counter: %d" 1344 " timeout: %ld\n", 1345 asoc->init_err_counter, 1346 asoc->timeouts[SCTP_EVENT_TIMEOUT_T1_COOKIE]); 1347 1348 /* If we've sent any data bundled with 1349 * COOKIE-ECHO we need to resend. 1350 */ 1351 list_for_each(pos, &asoc->peer.transport_addr_list) { 1352 t = list_entry(pos, struct sctp_transport, 1353 transports); 1354 sctp_retransmit_mark(&asoc->outqueue, t, 0); 1355 } 1356 1357 sctp_add_cmd_sf(commands, 1358 SCTP_CMD_TIMER_RESTART, 1359 SCTP_TO(SCTP_EVENT_TIMEOUT_T1_COOKIE)); 1360 break; 1361 1362 case SCTP_CMD_INIT_FAILED: 1363 sctp_cmd_init_failed(commands, asoc, cmd->obj.u32); 1364 break; 1365 1366 case SCTP_CMD_ASSOC_FAILED: 1367 sctp_cmd_assoc_failed(commands, asoc, event_type, 1368 subtype, chunk, cmd->obj.u32); 1369 break; 1370 1371 case SCTP_CMD_INIT_COUNTER_INC: 1372 asoc->init_err_counter++; 1373 break; 1374 1375 case SCTP_CMD_INIT_COUNTER_RESET: 1376 asoc->init_err_counter = 0; 1377 asoc->init_cycle = 0; 1378 break; 1379 1380 case SCTP_CMD_REPORT_DUP: 1381 sctp_tsnmap_mark_dup(&asoc->peer.tsn_map, 1382 cmd->obj.u32); 1383 break; 1384 1385 case SCTP_CMD_REPORT_BAD_TAG: 1386 SCTP_DEBUG_PRINTK("vtag mismatch!\n"); 1387 break; 1388 1389 case SCTP_CMD_STRIKE: 1390 /* Mark one strike against a transport. */ 1391 sctp_do_8_2_transport_strike(asoc, cmd->obj.transport); 1392 break; 1393 1394 case SCTP_CMD_TRANSPORT_RESET: 1395 t = cmd->obj.transport; 1396 sctp_cmd_transport_reset(commands, asoc, t); 1397 break; 1398 1399 case SCTP_CMD_TRANSPORT_ON: 1400 t = cmd->obj.transport; 1401 sctp_cmd_transport_on(commands, asoc, t, chunk); 1402 break; 1403 1404 case SCTP_CMD_HB_TIMERS_START: 1405 sctp_cmd_hb_timers_start(commands, asoc); 1406 break; 1407 1408 case SCTP_CMD_HB_TIMER_UPDATE: 1409 t = cmd->obj.transport; 1410 sctp_cmd_hb_timer_update(commands, asoc, t); 1411 break; 1412 1413 case SCTP_CMD_HB_TIMERS_STOP: 1414 sctp_cmd_hb_timers_stop(commands, asoc); 1415 break; 1416 1417 case SCTP_CMD_REPORT_ERROR: 1418 error = cmd->obj.error; 1419 break; 1420 1421 case SCTP_CMD_PROCESS_CTSN: 1422 /* Dummy up a SACK for processing. */ 1423 sackh.cum_tsn_ack = cmd->obj.u32; 1424 sackh.a_rwnd = 0; 1425 sackh.num_gap_ack_blocks = 0; 1426 sackh.num_dup_tsns = 0; 1427 sctp_add_cmd_sf(commands, SCTP_CMD_PROCESS_SACK, 1428 SCTP_SACKH(&sackh)); 1429 break; 1430 1431 case SCTP_CMD_DISCARD_PACKET: 1432 /* We need to discard the whole packet. */ 1433 chunk->pdiscard = 1; 1434 break; 1435 1436 case SCTP_CMD_RTO_PENDING: 1437 t = cmd->obj.transport; 1438 t->rto_pending = 1; 1439 break; 1440 1441 case SCTP_CMD_PART_DELIVER: 1442 sctp_ulpq_partial_delivery(&asoc->ulpq, cmd->obj.ptr, 1443 GFP_ATOMIC); 1444 break; 1445 1446 case SCTP_CMD_RENEGE: 1447 sctp_ulpq_renege(&asoc->ulpq, cmd->obj.ptr, 1448 GFP_ATOMIC); 1449 break; 1450 1451 case SCTP_CMD_SETUP_T4: 1452 sctp_cmd_setup_t4(commands, asoc, cmd->obj.ptr); 1453 break; 1454 1455 case SCTP_CMD_PROCESS_OPERR: 1456 sctp_cmd_process_operr(commands, asoc, chunk); 1457 break; 1458 case SCTP_CMD_CLEAR_INIT_TAG: 1459 asoc->peer.i.init_tag = 0; 1460 break; 1461 case SCTP_CMD_DEL_NON_PRIMARY: 1462 sctp_cmd_del_non_primary(asoc); 1463 break; 1464 case SCTP_CMD_T3_RTX_TIMERS_STOP: 1465 sctp_cmd_t3_rtx_timers_stop(commands, asoc); 1466 break; 1467 case SCTP_CMD_FORCE_PRIM_RETRAN: 1468 t = asoc->peer.retran_path; 1469 asoc->peer.retran_path = asoc->peer.primary_path; 1470 error = sctp_outq_uncork(&asoc->outqueue); 1471 local_cork = 0; 1472 asoc->peer.retran_path = t; 1473 break; 1474 case SCTP_CMD_SET_SK_ERR: 1475 sctp_cmd_set_sk_err(asoc, cmd->obj.error); 1476 break; 1477 default: 1478 printk(KERN_WARNING "Impossible command: %u, %p\n", 1479 cmd->verb, cmd->obj.ptr); 1480 break; 1481 }; 1482 if (error) 1483 break; 1484 } 1485 1486 out: 1487 if (local_cork) 1488 sctp_outq_uncork(&asoc->outqueue); 1489 return error; 1490 nomem: 1491 error = -ENOMEM; 1492 goto out; 1493 } 1494 1495