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 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 asoc->peer.sack_cnt++; 194 195 /* Set the SACK delay timeout based on the 196 * SACK delay for the last transport 197 * data was received from, or the default 198 * for the association. 199 */ 200 if (trans) { 201 /* We will need a SACK for the next packet. */ 202 if (asoc->peer.sack_cnt >= trans->sackfreq - 1) 203 asoc->peer.sack_needed = 1; 204 205 asoc->timeouts[SCTP_EVENT_TIMEOUT_SACK] = 206 trans->sackdelay; 207 } else { 208 /* We will need a SACK for the next packet. */ 209 if (asoc->peer.sack_cnt >= asoc->sackfreq - 1) 210 asoc->peer.sack_needed = 1; 211 212 asoc->timeouts[SCTP_EVENT_TIMEOUT_SACK] = 213 asoc->sackdelay; 214 } 215 216 /* Restart the SACK timer. */ 217 sctp_add_cmd_sf(commands, SCTP_CMD_TIMER_RESTART, 218 SCTP_TO(SCTP_EVENT_TIMEOUT_SACK)); 219 } else { 220 if (asoc->a_rwnd > asoc->rwnd) 221 asoc->a_rwnd = asoc->rwnd; 222 sack = sctp_make_sack(asoc); 223 if (!sack) 224 goto nomem; 225 226 asoc->peer.sack_needed = 0; 227 asoc->peer.sack_cnt = 0; 228 229 sctp_add_cmd_sf(commands, SCTP_CMD_REPLY, SCTP_CHUNK(sack)); 230 231 /* Stop the SACK timer. */ 232 sctp_add_cmd_sf(commands, SCTP_CMD_TIMER_STOP, 233 SCTP_TO(SCTP_EVENT_TIMEOUT_SACK)); 234 } 235 236 return error; 237 nomem: 238 error = -ENOMEM; 239 return error; 240 } 241 242 /* When the T3-RTX timer expires, it calls this function to create the 243 * relevant state machine event. 244 */ 245 void sctp_generate_t3_rtx_event(unsigned long peer) 246 { 247 int error; 248 struct sctp_transport *transport = (struct sctp_transport *) peer; 249 struct sctp_association *asoc = transport->asoc; 250 251 /* Check whether a task is in the sock. */ 252 253 sctp_bh_lock_sock(asoc->base.sk); 254 if (sock_owned_by_user(asoc->base.sk)) { 255 SCTP_DEBUG_PRINTK("%s:Sock is busy.\n", __func__); 256 257 /* Try again later. */ 258 if (!mod_timer(&transport->T3_rtx_timer, jiffies + (HZ/20))) 259 sctp_transport_hold(transport); 260 goto out_unlock; 261 } 262 263 /* Is this transport really dead and just waiting around for 264 * the timer to let go of the reference? 265 */ 266 if (transport->dead) 267 goto out_unlock; 268 269 /* Run through the state machine. */ 270 error = sctp_do_sm(SCTP_EVENT_T_TIMEOUT, 271 SCTP_ST_TIMEOUT(SCTP_EVENT_TIMEOUT_T3_RTX), 272 asoc->state, 273 asoc->ep, asoc, 274 transport, GFP_ATOMIC); 275 276 if (error) 277 asoc->base.sk->sk_err = -error; 278 279 out_unlock: 280 sctp_bh_unlock_sock(asoc->base.sk); 281 sctp_transport_put(transport); 282 } 283 284 /* This is a sa interface for producing timeout events. It works 285 * for timeouts which use the association as their parameter. 286 */ 287 static void sctp_generate_timeout_event(struct sctp_association *asoc, 288 sctp_event_timeout_t timeout_type) 289 { 290 int error = 0; 291 292 sctp_bh_lock_sock(asoc->base.sk); 293 if (sock_owned_by_user(asoc->base.sk)) { 294 SCTP_DEBUG_PRINTK("%s:Sock is busy: timer %d\n", 295 __func__, 296 timeout_type); 297 298 /* Try again later. */ 299 if (!mod_timer(&asoc->timers[timeout_type], jiffies + (HZ/20))) 300 sctp_association_hold(asoc); 301 goto out_unlock; 302 } 303 304 /* Is this association really dead and just waiting around for 305 * the timer to let go of the reference? 306 */ 307 if (asoc->base.dead) 308 goto out_unlock; 309 310 /* Run through the state machine. */ 311 error = sctp_do_sm(SCTP_EVENT_T_TIMEOUT, 312 SCTP_ST_TIMEOUT(timeout_type), 313 asoc->state, asoc->ep, asoc, 314 (void *)timeout_type, GFP_ATOMIC); 315 316 if (error) 317 asoc->base.sk->sk_err = -error; 318 319 out_unlock: 320 sctp_bh_unlock_sock(asoc->base.sk); 321 sctp_association_put(asoc); 322 } 323 324 static void sctp_generate_t1_cookie_event(unsigned long data) 325 { 326 struct sctp_association *asoc = (struct sctp_association *) data; 327 sctp_generate_timeout_event(asoc, SCTP_EVENT_TIMEOUT_T1_COOKIE); 328 } 329 330 static void sctp_generate_t1_init_event(unsigned long data) 331 { 332 struct sctp_association *asoc = (struct sctp_association *) data; 333 sctp_generate_timeout_event(asoc, SCTP_EVENT_TIMEOUT_T1_INIT); 334 } 335 336 static void sctp_generate_t2_shutdown_event(unsigned long data) 337 { 338 struct sctp_association *asoc = (struct sctp_association *) data; 339 sctp_generate_timeout_event(asoc, SCTP_EVENT_TIMEOUT_T2_SHUTDOWN); 340 } 341 342 static void sctp_generate_t4_rto_event(unsigned long data) 343 { 344 struct sctp_association *asoc = (struct sctp_association *) data; 345 sctp_generate_timeout_event(asoc, SCTP_EVENT_TIMEOUT_T4_RTO); 346 } 347 348 static void sctp_generate_t5_shutdown_guard_event(unsigned long data) 349 { 350 struct sctp_association *asoc = (struct sctp_association *)data; 351 sctp_generate_timeout_event(asoc, 352 SCTP_EVENT_TIMEOUT_T5_SHUTDOWN_GUARD); 353 354 } /* sctp_generate_t5_shutdown_guard_event() */ 355 356 static void sctp_generate_autoclose_event(unsigned long data) 357 { 358 struct sctp_association *asoc = (struct sctp_association *) data; 359 sctp_generate_timeout_event(asoc, SCTP_EVENT_TIMEOUT_AUTOCLOSE); 360 } 361 362 /* Generate a heart beat event. If the sock is busy, reschedule. Make 363 * sure that the transport is still valid. 364 */ 365 void sctp_generate_heartbeat_event(unsigned long data) 366 { 367 int error = 0; 368 struct sctp_transport *transport = (struct sctp_transport *) data; 369 struct sctp_association *asoc = transport->asoc; 370 371 sctp_bh_lock_sock(asoc->base.sk); 372 if (sock_owned_by_user(asoc->base.sk)) { 373 SCTP_DEBUG_PRINTK("%s:Sock is busy.\n", __func__); 374 375 /* Try again later. */ 376 if (!mod_timer(&transport->hb_timer, jiffies + (HZ/20))) 377 sctp_transport_hold(transport); 378 goto out_unlock; 379 } 380 381 /* Is this structure just waiting around for us to actually 382 * get destroyed? 383 */ 384 if (transport->dead) 385 goto out_unlock; 386 387 error = sctp_do_sm(SCTP_EVENT_T_TIMEOUT, 388 SCTP_ST_TIMEOUT(SCTP_EVENT_TIMEOUT_HEARTBEAT), 389 asoc->state, asoc->ep, asoc, 390 transport, GFP_ATOMIC); 391 392 if (error) 393 asoc->base.sk->sk_err = -error; 394 395 out_unlock: 396 sctp_bh_unlock_sock(asoc->base.sk); 397 sctp_transport_put(transport); 398 } 399 400 /* Inject a SACK Timeout event into the state machine. */ 401 static void sctp_generate_sack_event(unsigned long data) 402 { 403 struct sctp_association *asoc = (struct sctp_association *) data; 404 sctp_generate_timeout_event(asoc, SCTP_EVENT_TIMEOUT_SACK); 405 } 406 407 sctp_timer_event_t *sctp_timer_events[SCTP_NUM_TIMEOUT_TYPES] = { 408 NULL, 409 sctp_generate_t1_cookie_event, 410 sctp_generate_t1_init_event, 411 sctp_generate_t2_shutdown_event, 412 NULL, 413 sctp_generate_t4_rto_event, 414 sctp_generate_t5_shutdown_guard_event, 415 NULL, 416 sctp_generate_sack_event, 417 sctp_generate_autoclose_event, 418 }; 419 420 421 /* RFC 2960 8.2 Path Failure Detection 422 * 423 * When its peer endpoint is multi-homed, an endpoint should keep a 424 * error counter for each of the destination transport addresses of the 425 * peer endpoint. 426 * 427 * Each time the T3-rtx timer expires on any address, or when a 428 * HEARTBEAT sent to an idle address is not acknowledged within a RTO, 429 * the error counter of that destination address will be incremented. 430 * When the value in the error counter exceeds the protocol parameter 431 * 'Path.Max.Retrans' of that destination address, the endpoint should 432 * mark the destination transport address as inactive, and a 433 * notification SHOULD be sent to the upper layer. 434 * 435 */ 436 static void sctp_do_8_2_transport_strike(struct sctp_association *asoc, 437 struct sctp_transport *transport) 438 { 439 /* The check for association's overall error counter exceeding the 440 * threshold is done in the state function. 441 */ 442 /* When probing UNCONFIRMED addresses, the association overall 443 * error count is NOT incremented 444 */ 445 if (transport->state != SCTP_UNCONFIRMED) 446 asoc->overall_error_count++; 447 448 if (transport->state != SCTP_INACTIVE && 449 (transport->error_count++ >= transport->pathmaxrxt)) { 450 SCTP_DEBUG_PRINTK_IPADDR("transport_strike:association %p", 451 " transport IP: port:%d failed.\n", 452 asoc, 453 (&transport->ipaddr), 454 ntohs(transport->ipaddr.v4.sin_port)); 455 sctp_assoc_control_transport(asoc, transport, 456 SCTP_TRANSPORT_DOWN, 457 SCTP_FAILED_THRESHOLD); 458 } 459 460 /* E2) For the destination address for which the timer 461 * expires, set RTO <- RTO * 2 ("back off the timer"). The 462 * maximum value discussed in rule C7 above (RTO.max) may be 463 * used to provide an upper bound to this doubling operation. 464 */ 465 transport->last_rto = transport->rto; 466 transport->rto = min((transport->rto * 2), transport->asoc->rto_max); 467 } 468 469 /* Worker routine to handle INIT command failure. */ 470 static void sctp_cmd_init_failed(sctp_cmd_seq_t *commands, 471 struct sctp_association *asoc, 472 unsigned error) 473 { 474 struct sctp_ulpevent *event; 475 476 event = sctp_ulpevent_make_assoc_change(asoc,0, SCTP_CANT_STR_ASSOC, 477 (__u16)error, 0, 0, NULL, 478 GFP_ATOMIC); 479 480 if (event) 481 sctp_add_cmd_sf(commands, SCTP_CMD_EVENT_ULP, 482 SCTP_ULPEVENT(event)); 483 484 sctp_add_cmd_sf(commands, SCTP_CMD_NEW_STATE, 485 SCTP_STATE(SCTP_STATE_CLOSED)); 486 487 /* SEND_FAILED sent later when cleaning up the association. */ 488 asoc->outqueue.error = error; 489 sctp_add_cmd_sf(commands, SCTP_CMD_DELETE_TCB, SCTP_NULL()); 490 } 491 492 /* Worker routine to handle SCTP_CMD_ASSOC_FAILED. */ 493 static void sctp_cmd_assoc_failed(sctp_cmd_seq_t *commands, 494 struct sctp_association *asoc, 495 sctp_event_t event_type, 496 sctp_subtype_t subtype, 497 struct sctp_chunk *chunk, 498 unsigned error) 499 { 500 struct sctp_ulpevent *event; 501 502 /* Cancel any partial delivery in progress. */ 503 sctp_ulpq_abort_pd(&asoc->ulpq, GFP_ATOMIC); 504 505 if (event_type == SCTP_EVENT_T_CHUNK && subtype.chunk == SCTP_CID_ABORT) 506 event = sctp_ulpevent_make_assoc_change(asoc, 0, SCTP_COMM_LOST, 507 (__u16)error, 0, 0, chunk, 508 GFP_ATOMIC); 509 else 510 event = sctp_ulpevent_make_assoc_change(asoc, 0, SCTP_COMM_LOST, 511 (__u16)error, 0, 0, NULL, 512 GFP_ATOMIC); 513 if (event) 514 sctp_add_cmd_sf(commands, SCTP_CMD_EVENT_ULP, 515 SCTP_ULPEVENT(event)); 516 517 sctp_add_cmd_sf(commands, SCTP_CMD_NEW_STATE, 518 SCTP_STATE(SCTP_STATE_CLOSED)); 519 520 /* SEND_FAILED sent later when cleaning up the association. */ 521 asoc->outqueue.error = error; 522 sctp_add_cmd_sf(commands, SCTP_CMD_DELETE_TCB, SCTP_NULL()); 523 } 524 525 /* Process an init chunk (may be real INIT/INIT-ACK or an embedded INIT 526 * inside the cookie. In reality, this is only used for INIT-ACK processing 527 * since all other cases use "temporary" associations and can do all 528 * their work in statefuns directly. 529 */ 530 static int sctp_cmd_process_init(sctp_cmd_seq_t *commands, 531 struct sctp_association *asoc, 532 struct sctp_chunk *chunk, 533 sctp_init_chunk_t *peer_init, 534 gfp_t gfp) 535 { 536 int error; 537 538 /* We only process the init as a sideeffect in a single 539 * case. This is when we process the INIT-ACK. If we 540 * fail during INIT processing (due to malloc problems), 541 * just return the error and stop processing the stack. 542 */ 543 if (!sctp_process_init(asoc, chunk->chunk_hdr->type, 544 sctp_source(chunk), peer_init, gfp)) 545 error = -ENOMEM; 546 else 547 error = 0; 548 549 return error; 550 } 551 552 /* Helper function to break out starting up of heartbeat timers. */ 553 static void sctp_cmd_hb_timers_start(sctp_cmd_seq_t *cmds, 554 struct sctp_association *asoc) 555 { 556 struct sctp_transport *t; 557 558 /* Start a heartbeat timer for each transport on the association. 559 * hold a reference on the transport to make sure none of 560 * the needed data structures go away. 561 */ 562 list_for_each_entry(t, &asoc->peer.transport_addr_list, transports) { 563 564 if (!mod_timer(&t->hb_timer, sctp_transport_timeout(t))) 565 sctp_transport_hold(t); 566 } 567 } 568 569 static void sctp_cmd_hb_timers_stop(sctp_cmd_seq_t *cmds, 570 struct sctp_association *asoc) 571 { 572 struct sctp_transport *t; 573 574 /* Stop all heartbeat timers. */ 575 576 list_for_each_entry(t, &asoc->peer.transport_addr_list, 577 transports) { 578 if (del_timer(&t->hb_timer)) 579 sctp_transport_put(t); 580 } 581 } 582 583 /* Helper function to stop any pending T3-RTX timers */ 584 static void sctp_cmd_t3_rtx_timers_stop(sctp_cmd_seq_t *cmds, 585 struct sctp_association *asoc) 586 { 587 struct sctp_transport *t; 588 589 list_for_each_entry(t, &asoc->peer.transport_addr_list, 590 transports) { 591 if (timer_pending(&t->T3_rtx_timer) && 592 del_timer(&t->T3_rtx_timer)) { 593 sctp_transport_put(t); 594 } 595 } 596 } 597 598 599 /* Helper function to update the heartbeat timer. */ 600 static void sctp_cmd_hb_timer_update(sctp_cmd_seq_t *cmds, 601 struct sctp_transport *t) 602 { 603 /* Update the heartbeat timer. */ 604 if (!mod_timer(&t->hb_timer, sctp_transport_timeout(t))) 605 sctp_transport_hold(t); 606 } 607 608 /* Helper function to handle the reception of an HEARTBEAT ACK. */ 609 static void sctp_cmd_transport_on(sctp_cmd_seq_t *cmds, 610 struct sctp_association *asoc, 611 struct sctp_transport *t, 612 struct sctp_chunk *chunk) 613 { 614 sctp_sender_hb_info_t *hbinfo; 615 616 /* 8.3 Upon the receipt of the HEARTBEAT ACK, the sender of the 617 * HEARTBEAT should clear the error counter of the destination 618 * transport address to which the HEARTBEAT was sent. 619 * The association's overall error count is also cleared. 620 */ 621 t->error_count = 0; 622 t->asoc->overall_error_count = 0; 623 624 /* Mark the destination transport address as active if it is not so 625 * marked. 626 */ 627 if ((t->state == SCTP_INACTIVE) || (t->state == SCTP_UNCONFIRMED)) 628 sctp_assoc_control_transport(asoc, t, SCTP_TRANSPORT_UP, 629 SCTP_HEARTBEAT_SUCCESS); 630 631 /* The receiver of the HEARTBEAT ACK should also perform an 632 * RTT measurement for that destination transport address 633 * using the time value carried in the HEARTBEAT ACK chunk. 634 * If the transport's rto_pending variable has been cleared, 635 * it was most likely due to a retransmit. However, we want 636 * to re-enable it to properly update the rto. 637 */ 638 if (t->rto_pending == 0) 639 t->rto_pending = 1; 640 641 hbinfo = (sctp_sender_hb_info_t *) chunk->skb->data; 642 sctp_transport_update_rto(t, (jiffies - hbinfo->sent_at)); 643 644 /* Update the heartbeat timer. */ 645 if (!mod_timer(&t->hb_timer, sctp_transport_timeout(t))) 646 sctp_transport_hold(t); 647 } 648 649 /* Helper function to do a transport reset at the expiry of the hearbeat 650 * timer. 651 */ 652 static void sctp_cmd_transport_reset(sctp_cmd_seq_t *cmds, 653 struct sctp_association *asoc, 654 struct sctp_transport *t) 655 { 656 sctp_transport_lower_cwnd(t, SCTP_LOWER_CWND_INACTIVE); 657 658 /* Mark one strike against a transport. */ 659 sctp_do_8_2_transport_strike(asoc, t); 660 } 661 662 /* Helper function to process the process SACK command. */ 663 static int sctp_cmd_process_sack(sctp_cmd_seq_t *cmds, 664 struct sctp_association *asoc, 665 struct sctp_sackhdr *sackh) 666 { 667 int err = 0; 668 669 if (sctp_outq_sack(&asoc->outqueue, sackh)) { 670 /* There are no more TSNs awaiting SACK. */ 671 err = sctp_do_sm(SCTP_EVENT_T_OTHER, 672 SCTP_ST_OTHER(SCTP_EVENT_NO_PENDING_TSN), 673 asoc->state, asoc->ep, asoc, NULL, 674 GFP_ATOMIC); 675 } 676 677 return err; 678 } 679 680 /* Helper function to set the timeout value for T2-SHUTDOWN timer and to set 681 * the transport for a shutdown chunk. 682 */ 683 static void sctp_cmd_setup_t2(sctp_cmd_seq_t *cmds, 684 struct sctp_association *asoc, 685 struct sctp_chunk *chunk) 686 { 687 struct sctp_transport *t; 688 689 t = sctp_assoc_choose_shutdown_transport(asoc); 690 asoc->shutdown_last_sent_to = t; 691 asoc->timeouts[SCTP_EVENT_TIMEOUT_T2_SHUTDOWN] = t->rto; 692 chunk->transport = t; 693 } 694 695 /* Helper function to change the state of an association. */ 696 static void sctp_cmd_new_state(sctp_cmd_seq_t *cmds, 697 struct sctp_association *asoc, 698 sctp_state_t state) 699 { 700 struct sock *sk = asoc->base.sk; 701 702 asoc->state = state; 703 704 SCTP_DEBUG_PRINTK("sctp_cmd_new_state: asoc %p[%s]\n", 705 asoc, sctp_state_tbl[state]); 706 707 if (sctp_style(sk, TCP)) { 708 /* Change the sk->sk_state of a TCP-style socket that has 709 * sucessfully completed a connect() call. 710 */ 711 if (sctp_state(asoc, ESTABLISHED) && sctp_sstate(sk, CLOSED)) 712 sk->sk_state = SCTP_SS_ESTABLISHED; 713 714 /* Set the RCV_SHUTDOWN flag when a SHUTDOWN is received. */ 715 if (sctp_state(asoc, SHUTDOWN_RECEIVED) && 716 sctp_sstate(sk, ESTABLISHED)) 717 sk->sk_shutdown |= RCV_SHUTDOWN; 718 } 719 720 if (sctp_state(asoc, COOKIE_WAIT)) { 721 /* Reset init timeouts since they may have been 722 * increased due to timer expirations. 723 */ 724 asoc->timeouts[SCTP_EVENT_TIMEOUT_T1_INIT] = 725 asoc->rto_initial; 726 asoc->timeouts[SCTP_EVENT_TIMEOUT_T1_COOKIE] = 727 asoc->rto_initial; 728 } 729 730 if (sctp_state(asoc, ESTABLISHED) || 731 sctp_state(asoc, CLOSED) || 732 sctp_state(asoc, SHUTDOWN_RECEIVED)) { 733 /* Wake up any processes waiting in the asoc's wait queue in 734 * sctp_wait_for_connect() or sctp_wait_for_sndbuf(). 735 */ 736 if (waitqueue_active(&asoc->wait)) 737 wake_up_interruptible(&asoc->wait); 738 739 /* Wake up any processes waiting in the sk's sleep queue of 740 * a TCP-style or UDP-style peeled-off socket in 741 * sctp_wait_for_accept() or sctp_wait_for_packet(). 742 * For a UDP-style socket, the waiters are woken up by the 743 * notifications. 744 */ 745 if (!sctp_style(sk, UDP)) 746 sk->sk_state_change(sk); 747 } 748 } 749 750 /* Helper function to delete an association. */ 751 static void sctp_cmd_delete_tcb(sctp_cmd_seq_t *cmds, 752 struct sctp_association *asoc) 753 { 754 struct sock *sk = asoc->base.sk; 755 756 /* If it is a non-temporary association belonging to a TCP-style 757 * listening socket that is not closed, do not free it so that accept() 758 * can pick it up later. 759 */ 760 if (sctp_style(sk, TCP) && sctp_sstate(sk, LISTENING) && 761 (!asoc->temp) && (sk->sk_shutdown != SHUTDOWN_MASK)) 762 return; 763 764 sctp_unhash_established(asoc); 765 sctp_association_free(asoc); 766 } 767 768 /* 769 * ADDIP Section 4.1 ASCONF Chunk Procedures 770 * A4) Start a T-4 RTO timer, using the RTO value of the selected 771 * destination address (we use active path instead of primary path just 772 * because primary path may be inactive. 773 */ 774 static void sctp_cmd_setup_t4(sctp_cmd_seq_t *cmds, 775 struct sctp_association *asoc, 776 struct sctp_chunk *chunk) 777 { 778 struct sctp_transport *t; 779 780 t = asoc->peer.active_path; 781 asoc->timeouts[SCTP_EVENT_TIMEOUT_T4_RTO] = t->rto; 782 chunk->transport = t; 783 } 784 785 /* Process an incoming Operation Error Chunk. */ 786 static void sctp_cmd_process_operr(sctp_cmd_seq_t *cmds, 787 struct sctp_association *asoc, 788 struct sctp_chunk *chunk) 789 { 790 struct sctp_operr_chunk *operr_chunk; 791 struct sctp_errhdr *err_hdr; 792 793 operr_chunk = (struct sctp_operr_chunk *)chunk->chunk_hdr; 794 err_hdr = &operr_chunk->err_hdr; 795 796 switch (err_hdr->cause) { 797 case SCTP_ERROR_UNKNOWN_CHUNK: 798 { 799 struct sctp_chunkhdr *unk_chunk_hdr; 800 801 unk_chunk_hdr = (struct sctp_chunkhdr *)err_hdr->variable; 802 switch (unk_chunk_hdr->type) { 803 /* ADDIP 4.1 A9) If the peer responds to an ASCONF with an 804 * ERROR chunk reporting that it did not recognized the ASCONF 805 * chunk type, the sender of the ASCONF MUST NOT send any 806 * further ASCONF chunks and MUST stop its T-4 timer. 807 */ 808 case SCTP_CID_ASCONF: 809 asoc->peer.asconf_capable = 0; 810 sctp_add_cmd_sf(cmds, SCTP_CMD_TIMER_STOP, 811 SCTP_TO(SCTP_EVENT_TIMEOUT_T4_RTO)); 812 break; 813 default: 814 break; 815 } 816 break; 817 } 818 default: 819 break; 820 } 821 } 822 823 /* Process variable FWDTSN chunk information. */ 824 static void sctp_cmd_process_fwdtsn(struct sctp_ulpq *ulpq, 825 struct sctp_chunk *chunk) 826 { 827 struct sctp_fwdtsn_skip *skip; 828 /* Walk through all the skipped SSNs */ 829 sctp_walk_fwdtsn(skip, chunk) { 830 sctp_ulpq_skip(ulpq, ntohs(skip->stream), ntohs(skip->ssn)); 831 } 832 833 return; 834 } 835 836 /* Helper function to remove the association non-primary peer 837 * transports. 838 */ 839 static void sctp_cmd_del_non_primary(struct sctp_association *asoc) 840 { 841 struct sctp_transport *t; 842 struct list_head *pos; 843 struct list_head *temp; 844 845 list_for_each_safe(pos, temp, &asoc->peer.transport_addr_list) { 846 t = list_entry(pos, struct sctp_transport, transports); 847 if (!sctp_cmp_addr_exact(&t->ipaddr, 848 &asoc->peer.primary_addr)) { 849 sctp_assoc_del_peer(asoc, &t->ipaddr); 850 } 851 } 852 853 return; 854 } 855 856 /* Helper function to set sk_err on a 1-1 style socket. */ 857 static void sctp_cmd_set_sk_err(struct sctp_association *asoc, int error) 858 { 859 struct sock *sk = asoc->base.sk; 860 861 if (!sctp_style(sk, UDP)) 862 sk->sk_err = error; 863 } 864 865 /* Helper function to generate an association change event */ 866 static void sctp_cmd_assoc_change(sctp_cmd_seq_t *commands, 867 struct sctp_association *asoc, 868 u8 state) 869 { 870 struct sctp_ulpevent *ev; 871 872 ev = sctp_ulpevent_make_assoc_change(asoc, 0, state, 0, 873 asoc->c.sinit_num_ostreams, 874 asoc->c.sinit_max_instreams, 875 NULL, GFP_ATOMIC); 876 if (ev) 877 sctp_ulpq_tail_event(&asoc->ulpq, ev); 878 } 879 880 /* Helper function to generate an adaptation indication event */ 881 static void sctp_cmd_adaptation_ind(sctp_cmd_seq_t *commands, 882 struct sctp_association *asoc) 883 { 884 struct sctp_ulpevent *ev; 885 886 ev = sctp_ulpevent_make_adaptation_indication(asoc, GFP_ATOMIC); 887 888 if (ev) 889 sctp_ulpq_tail_event(&asoc->ulpq, ev); 890 } 891 892 /* These three macros allow us to pull the debugging code out of the 893 * main flow of sctp_do_sm() to keep attention focused on the real 894 * functionality there. 895 */ 896 #define DEBUG_PRE \ 897 SCTP_DEBUG_PRINTK("sctp_do_sm prefn: " \ 898 "ep %p, %s, %s, asoc %p[%s], %s\n", \ 899 ep, sctp_evttype_tbl[event_type], \ 900 (*debug_fn)(subtype), asoc, \ 901 sctp_state_tbl[state], state_fn->name) 902 903 #define DEBUG_POST \ 904 SCTP_DEBUG_PRINTK("sctp_do_sm postfn: " \ 905 "asoc %p, status: %s\n", \ 906 asoc, sctp_status_tbl[status]) 907 908 #define DEBUG_POST_SFX \ 909 SCTP_DEBUG_PRINTK("sctp_do_sm post sfx: error %d, asoc %p[%s]\n", \ 910 error, asoc, \ 911 sctp_state_tbl[(asoc && sctp_id2assoc(ep->base.sk, \ 912 sctp_assoc2id(asoc)))?asoc->state:SCTP_STATE_CLOSED]) 913 914 /* 915 * This is the master state machine processing function. 916 * 917 * If you want to understand all of lksctp, this is a 918 * good place to start. 919 */ 920 int sctp_do_sm(sctp_event_t event_type, sctp_subtype_t subtype, 921 sctp_state_t state, 922 struct sctp_endpoint *ep, 923 struct sctp_association *asoc, 924 void *event_arg, 925 gfp_t gfp) 926 { 927 sctp_cmd_seq_t commands; 928 const sctp_sm_table_entry_t *state_fn; 929 sctp_disposition_t status; 930 int error = 0; 931 typedef const char *(printfn_t)(sctp_subtype_t); 932 933 static printfn_t *table[] = { 934 NULL, sctp_cname, sctp_tname, sctp_oname, sctp_pname, 935 }; 936 printfn_t *debug_fn __attribute__ ((unused)) = table[event_type]; 937 938 /* Look up the state function, run it, and then process the 939 * side effects. These three steps are the heart of lksctp. 940 */ 941 state_fn = sctp_sm_lookup_event(event_type, state, subtype); 942 943 sctp_init_cmd_seq(&commands); 944 945 DEBUG_PRE; 946 status = (*state_fn->fn)(ep, asoc, subtype, event_arg, &commands); 947 DEBUG_POST; 948 949 error = sctp_side_effects(event_type, subtype, state, 950 ep, asoc, event_arg, status, 951 &commands, gfp); 952 DEBUG_POST_SFX; 953 954 return error; 955 } 956 957 #undef DEBUG_PRE 958 #undef DEBUG_POST 959 960 /***************************************************************** 961 * This the master state function side effect processing function. 962 *****************************************************************/ 963 static int sctp_side_effects(sctp_event_t event_type, sctp_subtype_t subtype, 964 sctp_state_t state, 965 struct sctp_endpoint *ep, 966 struct sctp_association *asoc, 967 void *event_arg, 968 sctp_disposition_t status, 969 sctp_cmd_seq_t *commands, 970 gfp_t gfp) 971 { 972 int error; 973 974 /* FIXME - Most of the dispositions left today would be categorized 975 * as "exceptional" dispositions. For those dispositions, it 976 * may not be proper to run through any of the commands at all. 977 * For example, the command interpreter might be run only with 978 * disposition SCTP_DISPOSITION_CONSUME. 979 */ 980 if (0 != (error = sctp_cmd_interpreter(event_type, subtype, state, 981 ep, asoc, 982 event_arg, status, 983 commands, gfp))) 984 goto bail; 985 986 switch (status) { 987 case SCTP_DISPOSITION_DISCARD: 988 SCTP_DEBUG_PRINTK("Ignored sctp protocol event - state %d, " 989 "event_type %d, event_id %d\n", 990 state, event_type, subtype.chunk); 991 break; 992 993 case SCTP_DISPOSITION_NOMEM: 994 /* We ran out of memory, so we need to discard this 995 * packet. 996 */ 997 /* BUG--we should now recover some memory, probably by 998 * reneging... 999 */ 1000 error = -ENOMEM; 1001 break; 1002 1003 case SCTP_DISPOSITION_DELETE_TCB: 1004 /* This should now be a command. */ 1005 break; 1006 1007 case SCTP_DISPOSITION_CONSUME: 1008 case SCTP_DISPOSITION_ABORT: 1009 /* 1010 * We should no longer have much work to do here as the 1011 * real work has been done as explicit commands above. 1012 */ 1013 break; 1014 1015 case SCTP_DISPOSITION_VIOLATION: 1016 if (net_ratelimit()) 1017 printk(KERN_ERR "sctp protocol violation state %d " 1018 "chunkid %d\n", state, subtype.chunk); 1019 break; 1020 1021 case SCTP_DISPOSITION_NOT_IMPL: 1022 printk(KERN_WARNING "sctp unimplemented feature in state %d, " 1023 "event_type %d, event_id %d\n", 1024 state, event_type, subtype.chunk); 1025 break; 1026 1027 case SCTP_DISPOSITION_BUG: 1028 printk(KERN_ERR "sctp bug in state %d, " 1029 "event_type %d, event_id %d\n", 1030 state, event_type, subtype.chunk); 1031 BUG(); 1032 break; 1033 1034 default: 1035 printk(KERN_ERR "sctp impossible disposition %d " 1036 "in state %d, event_type %d, event_id %d\n", 1037 status, state, event_type, subtype.chunk); 1038 BUG(); 1039 break; 1040 } 1041 1042 bail: 1043 return error; 1044 } 1045 1046 /******************************************************************** 1047 * 2nd Level Abstractions 1048 ********************************************************************/ 1049 1050 /* This is the side-effect interpreter. */ 1051 static int sctp_cmd_interpreter(sctp_event_t event_type, 1052 sctp_subtype_t subtype, 1053 sctp_state_t state, 1054 struct sctp_endpoint *ep, 1055 struct sctp_association *asoc, 1056 void *event_arg, 1057 sctp_disposition_t status, 1058 sctp_cmd_seq_t *commands, 1059 gfp_t gfp) 1060 { 1061 int error = 0; 1062 int force; 1063 sctp_cmd_t *cmd; 1064 struct sctp_chunk *new_obj; 1065 struct sctp_chunk *chunk = NULL; 1066 struct sctp_packet *packet; 1067 struct timer_list *timer; 1068 unsigned long timeout; 1069 struct sctp_transport *t; 1070 struct sctp_sackhdr sackh; 1071 int local_cork = 0; 1072 1073 if (SCTP_EVENT_T_TIMEOUT != event_type) 1074 chunk = (struct sctp_chunk *) event_arg; 1075 1076 /* Note: This whole file is a huge candidate for rework. 1077 * For example, each command could either have its own handler, so 1078 * the loop would look like: 1079 * while (cmds) 1080 * cmd->handle(x, y, z) 1081 * --jgrimm 1082 */ 1083 while (NULL != (cmd = sctp_next_cmd(commands))) { 1084 switch (cmd->verb) { 1085 case SCTP_CMD_NOP: 1086 /* Do nothing. */ 1087 break; 1088 1089 case SCTP_CMD_NEW_ASOC: 1090 /* Register a new association. */ 1091 if (local_cork) { 1092 sctp_outq_uncork(&asoc->outqueue); 1093 local_cork = 0; 1094 } 1095 asoc = cmd->obj.ptr; 1096 /* Register with the endpoint. */ 1097 sctp_endpoint_add_asoc(ep, asoc); 1098 sctp_hash_established(asoc); 1099 break; 1100 1101 case SCTP_CMD_UPDATE_ASSOC: 1102 sctp_assoc_update(asoc, cmd->obj.ptr); 1103 break; 1104 1105 case SCTP_CMD_PURGE_OUTQUEUE: 1106 sctp_outq_teardown(&asoc->outqueue); 1107 break; 1108 1109 case SCTP_CMD_DELETE_TCB: 1110 if (local_cork) { 1111 sctp_outq_uncork(&asoc->outqueue); 1112 local_cork = 0; 1113 } 1114 /* Delete the current association. */ 1115 sctp_cmd_delete_tcb(commands, asoc); 1116 asoc = NULL; 1117 break; 1118 1119 case SCTP_CMD_NEW_STATE: 1120 /* Enter a new state. */ 1121 sctp_cmd_new_state(commands, asoc, cmd->obj.state); 1122 break; 1123 1124 case SCTP_CMD_REPORT_TSN: 1125 /* Record the arrival of a TSN. */ 1126 sctp_tsnmap_mark(&asoc->peer.tsn_map, cmd->obj.u32); 1127 break; 1128 1129 case SCTP_CMD_REPORT_FWDTSN: 1130 /* Move the Cumulattive TSN Ack ahead. */ 1131 sctp_tsnmap_skip(&asoc->peer.tsn_map, cmd->obj.u32); 1132 1133 /* purge the fragmentation queue */ 1134 sctp_ulpq_reasm_flushtsn(&asoc->ulpq, cmd->obj.u32); 1135 1136 /* Abort any in progress partial delivery. */ 1137 sctp_ulpq_abort_pd(&asoc->ulpq, GFP_ATOMIC); 1138 break; 1139 1140 case SCTP_CMD_PROCESS_FWDTSN: 1141 sctp_cmd_process_fwdtsn(&asoc->ulpq, cmd->obj.ptr); 1142 break; 1143 1144 case SCTP_CMD_GEN_SACK: 1145 /* Generate a Selective ACK. 1146 * The argument tells us whether to just count 1147 * the packet and MAYBE generate a SACK, or 1148 * force a SACK out. 1149 */ 1150 force = cmd->obj.i32; 1151 error = sctp_gen_sack(asoc, force, commands); 1152 break; 1153 1154 case SCTP_CMD_PROCESS_SACK: 1155 /* Process an inbound SACK. */ 1156 error = sctp_cmd_process_sack(commands, asoc, 1157 cmd->obj.ptr); 1158 break; 1159 1160 case SCTP_CMD_GEN_INIT_ACK: 1161 /* Generate an INIT ACK chunk. */ 1162 new_obj = sctp_make_init_ack(asoc, chunk, GFP_ATOMIC, 1163 0); 1164 if (!new_obj) 1165 goto nomem; 1166 1167 sctp_add_cmd_sf(commands, SCTP_CMD_REPLY, 1168 SCTP_CHUNK(new_obj)); 1169 break; 1170 1171 case SCTP_CMD_PEER_INIT: 1172 /* Process a unified INIT from the peer. 1173 * Note: Only used during INIT-ACK processing. If 1174 * there is an error just return to the outter 1175 * layer which will bail. 1176 */ 1177 error = sctp_cmd_process_init(commands, asoc, chunk, 1178 cmd->obj.ptr, gfp); 1179 break; 1180 1181 case SCTP_CMD_GEN_COOKIE_ECHO: 1182 /* Generate a COOKIE ECHO chunk. */ 1183 new_obj = sctp_make_cookie_echo(asoc, chunk); 1184 if (!new_obj) { 1185 if (cmd->obj.ptr) 1186 sctp_chunk_free(cmd->obj.ptr); 1187 goto nomem; 1188 } 1189 sctp_add_cmd_sf(commands, SCTP_CMD_REPLY, 1190 SCTP_CHUNK(new_obj)); 1191 1192 /* If there is an ERROR chunk to be sent along with 1193 * the COOKIE_ECHO, send it, too. 1194 */ 1195 if (cmd->obj.ptr) 1196 sctp_add_cmd_sf(commands, SCTP_CMD_REPLY, 1197 SCTP_CHUNK(cmd->obj.ptr)); 1198 1199 /* FIXME - Eventually come up with a cleaner way to 1200 * enabling COOKIE-ECHO + DATA bundling during 1201 * multihoming stale cookie scenarios, the following 1202 * command plays with asoc->peer.retran_path to 1203 * avoid the problem of sending the COOKIE-ECHO and 1204 * DATA in different paths, which could result 1205 * in the association being ABORTed if the DATA chunk 1206 * is processed first by the server. Checking the 1207 * init error counter simply causes this command 1208 * to be executed only during failed attempts of 1209 * association establishment. 1210 */ 1211 if ((asoc->peer.retran_path != 1212 asoc->peer.primary_path) && 1213 (asoc->init_err_counter > 0)) { 1214 sctp_add_cmd_sf(commands, 1215 SCTP_CMD_FORCE_PRIM_RETRAN, 1216 SCTP_NULL()); 1217 } 1218 1219 break; 1220 1221 case SCTP_CMD_GEN_SHUTDOWN: 1222 /* Generate SHUTDOWN when in SHUTDOWN_SENT state. 1223 * Reset error counts. 1224 */ 1225 asoc->overall_error_count = 0; 1226 1227 /* Generate a SHUTDOWN chunk. */ 1228 new_obj = sctp_make_shutdown(asoc, chunk); 1229 if (!new_obj) 1230 goto nomem; 1231 sctp_add_cmd_sf(commands, SCTP_CMD_REPLY, 1232 SCTP_CHUNK(new_obj)); 1233 break; 1234 1235 case SCTP_CMD_CHUNK_ULP: 1236 /* Send a chunk to the sockets layer. */ 1237 SCTP_DEBUG_PRINTK("sm_sideff: %s %p, %s %p.\n", 1238 "chunk_up:", cmd->obj.ptr, 1239 "ulpq:", &asoc->ulpq); 1240 sctp_ulpq_tail_data(&asoc->ulpq, cmd->obj.ptr, 1241 GFP_ATOMIC); 1242 break; 1243 1244 case SCTP_CMD_EVENT_ULP: 1245 /* Send a notification to the sockets layer. */ 1246 SCTP_DEBUG_PRINTK("sm_sideff: %s %p, %s %p.\n", 1247 "event_up:",cmd->obj.ptr, 1248 "ulpq:",&asoc->ulpq); 1249 sctp_ulpq_tail_event(&asoc->ulpq, cmd->obj.ptr); 1250 break; 1251 1252 case SCTP_CMD_REPLY: 1253 /* If an caller has not already corked, do cork. */ 1254 if (!asoc->outqueue.cork) { 1255 sctp_outq_cork(&asoc->outqueue); 1256 local_cork = 1; 1257 } 1258 /* Send a chunk to our peer. */ 1259 error = sctp_outq_tail(&asoc->outqueue, cmd->obj.ptr); 1260 break; 1261 1262 case SCTP_CMD_SEND_PKT: 1263 /* Send a full packet to our peer. */ 1264 packet = cmd->obj.ptr; 1265 sctp_packet_transmit(packet); 1266 sctp_ootb_pkt_free(packet); 1267 break; 1268 1269 case SCTP_CMD_T1_RETRAN: 1270 /* Mark a transport for retransmission. */ 1271 sctp_retransmit(&asoc->outqueue, cmd->obj.transport, 1272 SCTP_RTXR_T1_RTX); 1273 break; 1274 1275 case SCTP_CMD_RETRAN: 1276 /* Mark a transport for retransmission. */ 1277 sctp_retransmit(&asoc->outqueue, cmd->obj.transport, 1278 SCTP_RTXR_T3_RTX); 1279 break; 1280 1281 case SCTP_CMD_TRANSMIT: 1282 /* Kick start transmission. */ 1283 error = sctp_outq_uncork(&asoc->outqueue); 1284 local_cork = 0; 1285 break; 1286 1287 case SCTP_CMD_ECN_CE: 1288 /* Do delayed CE processing. */ 1289 sctp_do_ecn_ce_work(asoc, cmd->obj.u32); 1290 break; 1291 1292 case SCTP_CMD_ECN_ECNE: 1293 /* Do delayed ECNE processing. */ 1294 new_obj = sctp_do_ecn_ecne_work(asoc, cmd->obj.u32, 1295 chunk); 1296 if (new_obj) 1297 sctp_add_cmd_sf(commands, SCTP_CMD_REPLY, 1298 SCTP_CHUNK(new_obj)); 1299 break; 1300 1301 case SCTP_CMD_ECN_CWR: 1302 /* Do delayed CWR processing. */ 1303 sctp_do_ecn_cwr_work(asoc, cmd->obj.u32); 1304 break; 1305 1306 case SCTP_CMD_SETUP_T2: 1307 sctp_cmd_setup_t2(commands, asoc, cmd->obj.ptr); 1308 break; 1309 1310 case SCTP_CMD_TIMER_START: 1311 timer = &asoc->timers[cmd->obj.to]; 1312 timeout = asoc->timeouts[cmd->obj.to]; 1313 BUG_ON(!timeout); 1314 1315 timer->expires = jiffies + timeout; 1316 sctp_association_hold(asoc); 1317 add_timer(timer); 1318 break; 1319 1320 case SCTP_CMD_TIMER_RESTART: 1321 timer = &asoc->timers[cmd->obj.to]; 1322 timeout = asoc->timeouts[cmd->obj.to]; 1323 if (!mod_timer(timer, jiffies + timeout)) 1324 sctp_association_hold(asoc); 1325 break; 1326 1327 case SCTP_CMD_TIMER_STOP: 1328 timer = &asoc->timers[cmd->obj.to]; 1329 if (timer_pending(timer) && del_timer(timer)) 1330 sctp_association_put(asoc); 1331 break; 1332 1333 case SCTP_CMD_INIT_CHOOSE_TRANSPORT: 1334 chunk = cmd->obj.ptr; 1335 t = sctp_assoc_choose_init_transport(asoc); 1336 asoc->init_last_sent_to = t; 1337 chunk->transport = t; 1338 t->init_sent_count++; 1339 break; 1340 1341 case SCTP_CMD_INIT_RESTART: 1342 /* Do the needed accounting and updates 1343 * associated with restarting an initialization 1344 * timer. Only multiply the timeout by two if 1345 * all transports have been tried at the current 1346 * timeout. 1347 */ 1348 t = asoc->init_last_sent_to; 1349 asoc->init_err_counter++; 1350 1351 if (t->init_sent_count > (asoc->init_cycle + 1)) { 1352 asoc->timeouts[SCTP_EVENT_TIMEOUT_T1_INIT] *= 2; 1353 if (asoc->timeouts[SCTP_EVENT_TIMEOUT_T1_INIT] > 1354 asoc->max_init_timeo) { 1355 asoc->timeouts[SCTP_EVENT_TIMEOUT_T1_INIT] = 1356 asoc->max_init_timeo; 1357 } 1358 asoc->init_cycle++; 1359 SCTP_DEBUG_PRINTK( 1360 "T1 INIT Timeout adjustment" 1361 " init_err_counter: %d" 1362 " cycle: %d" 1363 " timeout: %ld\n", 1364 asoc->init_err_counter, 1365 asoc->init_cycle, 1366 asoc->timeouts[SCTP_EVENT_TIMEOUT_T1_INIT]); 1367 } 1368 1369 sctp_add_cmd_sf(commands, SCTP_CMD_TIMER_RESTART, 1370 SCTP_TO(SCTP_EVENT_TIMEOUT_T1_INIT)); 1371 break; 1372 1373 case SCTP_CMD_COOKIEECHO_RESTART: 1374 /* Do the needed accounting and updates 1375 * associated with restarting an initialization 1376 * timer. Only multiply the timeout by two if 1377 * all transports have been tried at the current 1378 * timeout. 1379 */ 1380 asoc->init_err_counter++; 1381 1382 asoc->timeouts[SCTP_EVENT_TIMEOUT_T1_COOKIE] *= 2; 1383 if (asoc->timeouts[SCTP_EVENT_TIMEOUT_T1_COOKIE] > 1384 asoc->max_init_timeo) { 1385 asoc->timeouts[SCTP_EVENT_TIMEOUT_T1_COOKIE] = 1386 asoc->max_init_timeo; 1387 } 1388 SCTP_DEBUG_PRINTK( 1389 "T1 COOKIE Timeout adjustment" 1390 " init_err_counter: %d" 1391 " timeout: %ld\n", 1392 asoc->init_err_counter, 1393 asoc->timeouts[SCTP_EVENT_TIMEOUT_T1_COOKIE]); 1394 1395 /* If we've sent any data bundled with 1396 * COOKIE-ECHO we need to resend. 1397 */ 1398 list_for_each_entry(t, &asoc->peer.transport_addr_list, 1399 transports) { 1400 sctp_retransmit_mark(&asoc->outqueue, t, 1401 SCTP_RTXR_T1_RTX); 1402 } 1403 1404 sctp_add_cmd_sf(commands, 1405 SCTP_CMD_TIMER_RESTART, 1406 SCTP_TO(SCTP_EVENT_TIMEOUT_T1_COOKIE)); 1407 break; 1408 1409 case SCTP_CMD_INIT_FAILED: 1410 sctp_cmd_init_failed(commands, asoc, cmd->obj.err); 1411 break; 1412 1413 case SCTP_CMD_ASSOC_FAILED: 1414 sctp_cmd_assoc_failed(commands, asoc, event_type, 1415 subtype, chunk, cmd->obj.err); 1416 break; 1417 1418 case SCTP_CMD_INIT_COUNTER_INC: 1419 asoc->init_err_counter++; 1420 break; 1421 1422 case SCTP_CMD_INIT_COUNTER_RESET: 1423 asoc->init_err_counter = 0; 1424 asoc->init_cycle = 0; 1425 break; 1426 1427 case SCTP_CMD_REPORT_DUP: 1428 sctp_tsnmap_mark_dup(&asoc->peer.tsn_map, 1429 cmd->obj.u32); 1430 break; 1431 1432 case SCTP_CMD_REPORT_BAD_TAG: 1433 SCTP_DEBUG_PRINTK("vtag mismatch!\n"); 1434 break; 1435 1436 case SCTP_CMD_STRIKE: 1437 /* Mark one strike against a transport. */ 1438 sctp_do_8_2_transport_strike(asoc, cmd->obj.transport); 1439 break; 1440 1441 case SCTP_CMD_TRANSPORT_RESET: 1442 t = cmd->obj.transport; 1443 sctp_cmd_transport_reset(commands, asoc, t); 1444 break; 1445 1446 case SCTP_CMD_TRANSPORT_ON: 1447 t = cmd->obj.transport; 1448 sctp_cmd_transport_on(commands, asoc, t, chunk); 1449 break; 1450 1451 case SCTP_CMD_HB_TIMERS_START: 1452 sctp_cmd_hb_timers_start(commands, asoc); 1453 break; 1454 1455 case SCTP_CMD_HB_TIMER_UPDATE: 1456 t = cmd->obj.transport; 1457 sctp_cmd_hb_timer_update(commands, t); 1458 break; 1459 1460 case SCTP_CMD_HB_TIMERS_STOP: 1461 sctp_cmd_hb_timers_stop(commands, asoc); 1462 break; 1463 1464 case SCTP_CMD_REPORT_ERROR: 1465 error = cmd->obj.error; 1466 break; 1467 1468 case SCTP_CMD_PROCESS_CTSN: 1469 /* Dummy up a SACK for processing. */ 1470 sackh.cum_tsn_ack = cmd->obj.be32; 1471 sackh.a_rwnd = 0; 1472 sackh.num_gap_ack_blocks = 0; 1473 sackh.num_dup_tsns = 0; 1474 sctp_add_cmd_sf(commands, SCTP_CMD_PROCESS_SACK, 1475 SCTP_SACKH(&sackh)); 1476 break; 1477 1478 case SCTP_CMD_DISCARD_PACKET: 1479 /* We need to discard the whole packet. 1480 * Uncork the queue since there might be 1481 * responses pending 1482 */ 1483 chunk->pdiscard = 1; 1484 if (asoc) { 1485 sctp_outq_uncork(&asoc->outqueue); 1486 local_cork = 0; 1487 } 1488 break; 1489 1490 case SCTP_CMD_RTO_PENDING: 1491 t = cmd->obj.transport; 1492 t->rto_pending = 1; 1493 break; 1494 1495 case SCTP_CMD_PART_DELIVER: 1496 sctp_ulpq_partial_delivery(&asoc->ulpq, cmd->obj.ptr, 1497 GFP_ATOMIC); 1498 break; 1499 1500 case SCTP_CMD_RENEGE: 1501 sctp_ulpq_renege(&asoc->ulpq, cmd->obj.ptr, 1502 GFP_ATOMIC); 1503 break; 1504 1505 case SCTP_CMD_SETUP_T4: 1506 sctp_cmd_setup_t4(commands, asoc, cmd->obj.ptr); 1507 break; 1508 1509 case SCTP_CMD_PROCESS_OPERR: 1510 sctp_cmd_process_operr(commands, asoc, chunk); 1511 break; 1512 case SCTP_CMD_CLEAR_INIT_TAG: 1513 asoc->peer.i.init_tag = 0; 1514 break; 1515 case SCTP_CMD_DEL_NON_PRIMARY: 1516 sctp_cmd_del_non_primary(asoc); 1517 break; 1518 case SCTP_CMD_T3_RTX_TIMERS_STOP: 1519 sctp_cmd_t3_rtx_timers_stop(commands, asoc); 1520 break; 1521 case SCTP_CMD_FORCE_PRIM_RETRAN: 1522 t = asoc->peer.retran_path; 1523 asoc->peer.retran_path = asoc->peer.primary_path; 1524 error = sctp_outq_uncork(&asoc->outqueue); 1525 local_cork = 0; 1526 asoc->peer.retran_path = t; 1527 break; 1528 case SCTP_CMD_SET_SK_ERR: 1529 sctp_cmd_set_sk_err(asoc, cmd->obj.error); 1530 break; 1531 case SCTP_CMD_ASSOC_CHANGE: 1532 sctp_cmd_assoc_change(commands, asoc, 1533 cmd->obj.u8); 1534 break; 1535 case SCTP_CMD_ADAPTATION_IND: 1536 sctp_cmd_adaptation_ind(commands, asoc); 1537 break; 1538 1539 case SCTP_CMD_ASSOC_SHKEY: 1540 error = sctp_auth_asoc_init_active_key(asoc, 1541 GFP_ATOMIC); 1542 break; 1543 case SCTP_CMD_UPDATE_INITTAG: 1544 asoc->peer.i.init_tag = cmd->obj.u32; 1545 break; 1546 1547 default: 1548 printk(KERN_WARNING "Impossible command: %u, %p\n", 1549 cmd->verb, cmd->obj.ptr); 1550 break; 1551 } 1552 1553 if (error) 1554 break; 1555 } 1556 1557 out: 1558 /* If this is in response to a received chunk, wait until 1559 * we are done with the packet to open the queue so that we don't 1560 * send multiple packets in response to a single request. 1561 */ 1562 if (asoc && SCTP_EVENT_T_CHUNK == event_type && chunk) { 1563 if (chunk->end_of_packet || chunk->singleton) 1564 sctp_outq_uncork(&asoc->outqueue); 1565 } else if (local_cork) 1566 sctp_outq_uncork(&asoc->outqueue); 1567 return error; 1568 nomem: 1569 error = -ENOMEM; 1570 goto out; 1571 } 1572 1573