1 /* 2 * Connection tracking protocol helper module for SCTP. 3 * 4 * Copyright (c) 2004 Kiran Kumar Immidi <immidi_kiran@yahoo.com> 5 * Copyright (c) 2004-2012 Patrick McHardy <kaber@trash.net> 6 * 7 * SCTP is defined in RFC 2960. References to various sections in this code 8 * are to this RFC. 9 * 10 * This program is free software; you can redistribute it and/or modify 11 * it under the terms of the GNU General Public License version 2 as 12 * published by the Free Software Foundation. 13 */ 14 15 #include <linux/types.h> 16 #include <linux/timer.h> 17 #include <linux/netfilter.h> 18 #include <linux/in.h> 19 #include <linux/ip.h> 20 #include <linux/sctp.h> 21 #include <linux/string.h> 22 #include <linux/seq_file.h> 23 #include <linux/spinlock.h> 24 #include <linux/interrupt.h> 25 #include <net/sctp/checksum.h> 26 27 #include <net/netfilter/nf_log.h> 28 #include <net/netfilter/nf_conntrack.h> 29 #include <net/netfilter/nf_conntrack_l4proto.h> 30 #include <net/netfilter/nf_conntrack_ecache.h> 31 #include <net/netfilter/nf_conntrack_timeout.h> 32 33 /* FIXME: Examine ipfilter's timeouts and conntrack transitions more 34 closely. They're more complex. --RR 35 36 And so for me for SCTP :D -Kiran */ 37 38 static const char *const sctp_conntrack_names[] = { 39 "NONE", 40 "CLOSED", 41 "COOKIE_WAIT", 42 "COOKIE_ECHOED", 43 "ESTABLISHED", 44 "SHUTDOWN_SENT", 45 "SHUTDOWN_RECD", 46 "SHUTDOWN_ACK_SENT", 47 "HEARTBEAT_SENT", 48 "HEARTBEAT_ACKED", 49 }; 50 51 #define SECS * HZ 52 #define MINS * 60 SECS 53 #define HOURS * 60 MINS 54 #define DAYS * 24 HOURS 55 56 static const unsigned int sctp_timeouts[SCTP_CONNTRACK_MAX] = { 57 [SCTP_CONNTRACK_CLOSED] = 10 SECS, 58 [SCTP_CONNTRACK_COOKIE_WAIT] = 3 SECS, 59 [SCTP_CONNTRACK_COOKIE_ECHOED] = 3 SECS, 60 [SCTP_CONNTRACK_ESTABLISHED] = 5 DAYS, 61 [SCTP_CONNTRACK_SHUTDOWN_SENT] = 300 SECS / 1000, 62 [SCTP_CONNTRACK_SHUTDOWN_RECD] = 300 SECS / 1000, 63 [SCTP_CONNTRACK_SHUTDOWN_ACK_SENT] = 3 SECS, 64 [SCTP_CONNTRACK_HEARTBEAT_SENT] = 30 SECS, 65 [SCTP_CONNTRACK_HEARTBEAT_ACKED] = 210 SECS, 66 }; 67 68 #define sNO SCTP_CONNTRACK_NONE 69 #define sCL SCTP_CONNTRACK_CLOSED 70 #define sCW SCTP_CONNTRACK_COOKIE_WAIT 71 #define sCE SCTP_CONNTRACK_COOKIE_ECHOED 72 #define sES SCTP_CONNTRACK_ESTABLISHED 73 #define sSS SCTP_CONNTRACK_SHUTDOWN_SENT 74 #define sSR SCTP_CONNTRACK_SHUTDOWN_RECD 75 #define sSA SCTP_CONNTRACK_SHUTDOWN_ACK_SENT 76 #define sHS SCTP_CONNTRACK_HEARTBEAT_SENT 77 #define sHA SCTP_CONNTRACK_HEARTBEAT_ACKED 78 #define sIV SCTP_CONNTRACK_MAX 79 80 /* 81 These are the descriptions of the states: 82 83 NOTE: These state names are tantalizingly similar to the states of an 84 SCTP endpoint. But the interpretation of the states is a little different, 85 considering that these are the states of the connection and not of an end 86 point. Please note the subtleties. -Kiran 87 88 NONE - Nothing so far. 89 COOKIE WAIT - We have seen an INIT chunk in the original direction, or also 90 an INIT_ACK chunk in the reply direction. 91 COOKIE ECHOED - We have seen a COOKIE_ECHO chunk in the original direction. 92 ESTABLISHED - We have seen a COOKIE_ACK in the reply direction. 93 SHUTDOWN_SENT - We have seen a SHUTDOWN chunk in the original direction. 94 SHUTDOWN_RECD - We have seen a SHUTDOWN chunk in the reply directoin. 95 SHUTDOWN_ACK_SENT - We have seen a SHUTDOWN_ACK chunk in the direction opposite 96 to that of the SHUTDOWN chunk. 97 CLOSED - We have seen a SHUTDOWN_COMPLETE chunk in the direction of 98 the SHUTDOWN chunk. Connection is closed. 99 HEARTBEAT_SENT - We have seen a HEARTBEAT in a new flow. 100 HEARTBEAT_ACKED - We have seen a HEARTBEAT-ACK in the direction opposite to 101 that of the HEARTBEAT chunk. Secondary connection is 102 established. 103 */ 104 105 /* TODO 106 - I have assumed that the first INIT is in the original direction. 107 This messes things when an INIT comes in the reply direction in CLOSED 108 state. 109 - Check the error type in the reply dir before transitioning from 110 cookie echoed to closed. 111 - Sec 5.2.4 of RFC 2960 112 - Full Multi Homing support. 113 */ 114 115 /* SCTP conntrack state transitions */ 116 static const u8 sctp_conntracks[2][11][SCTP_CONNTRACK_MAX] = { 117 { 118 /* ORIGINAL */ 119 /* sNO, sCL, sCW, sCE, sES, sSS, sSR, sSA, sHS, sHA */ 120 /* init */ {sCW, sCW, sCW, sCE, sES, sSS, sSR, sSA, sCW, sHA}, 121 /* init_ack */ {sCL, sCL, sCW, sCE, sES, sSS, sSR, sSA, sCL, sHA}, 122 /* abort */ {sCL, sCL, sCL, sCL, sCL, sCL, sCL, sCL, sCL, sCL}, 123 /* shutdown */ {sCL, sCL, sCW, sCE, sSS, sSS, sSR, sSA, sCL, sSS}, 124 /* shutdown_ack */ {sSA, sCL, sCW, sCE, sES, sSA, sSA, sSA, sSA, sHA}, 125 /* error */ {sCL, sCL, sCW, sCE, sES, sSS, sSR, sSA, sCL, sHA},/* Can't have Stale cookie*/ 126 /* cookie_echo */ {sCL, sCL, sCE, sCE, sES, sSS, sSR, sSA, sCL, sHA},/* 5.2.4 - Big TODO */ 127 /* cookie_ack */ {sCL, sCL, sCW, sCE, sES, sSS, sSR, sSA, sCL, sHA},/* Can't come in orig dir */ 128 /* shutdown_comp*/ {sCL, sCL, sCW, sCE, sES, sSS, sSR, sCL, sCL, sHA}, 129 /* heartbeat */ {sHS, sCL, sCW, sCE, sES, sSS, sSR, sSA, sHS, sHA}, 130 /* heartbeat_ack*/ {sCL, sCL, sCW, sCE, sES, sSS, sSR, sSA, sHS, sHA} 131 }, 132 { 133 /* REPLY */ 134 /* sNO, sCL, sCW, sCE, sES, sSS, sSR, sSA, sHS, sHA */ 135 /* init */ {sIV, sCL, sCW, sCE, sES, sSS, sSR, sSA, sIV, sHA},/* INIT in sCL Big TODO */ 136 /* init_ack */ {sIV, sCL, sCW, sCE, sES, sSS, sSR, sSA, sIV, sHA}, 137 /* abort */ {sIV, sCL, sCL, sCL, sCL, sCL, sCL, sCL, sIV, sCL}, 138 /* shutdown */ {sIV, sCL, sCW, sCE, sSR, sSS, sSR, sSA, sIV, sSR}, 139 /* shutdown_ack */ {sIV, sCL, sCW, sCE, sES, sSA, sSA, sSA, sIV, sHA}, 140 /* error */ {sIV, sCL, sCW, sCL, sES, sSS, sSR, sSA, sIV, sHA}, 141 /* cookie_echo */ {sIV, sCL, sCW, sCE, sES, sSS, sSR, sSA, sIV, sHA},/* Can't come in reply dir */ 142 /* cookie_ack */ {sIV, sCL, sCW, sES, sES, sSS, sSR, sSA, sIV, sHA}, 143 /* shutdown_comp*/ {sIV, sCL, sCW, sCE, sES, sSS, sSR, sCL, sIV, sHA}, 144 /* heartbeat */ {sIV, sCL, sCW, sCE, sES, sSS, sSR, sSA, sHS, sHA}, 145 /* heartbeat_ack*/ {sIV, sCL, sCW, sCE, sES, sSS, sSR, sSA, sHA, sHA} 146 } 147 }; 148 149 static inline struct nf_sctp_net *sctp_pernet(struct net *net) 150 { 151 return &net->ct.nf_ct_proto.sctp; 152 } 153 154 #ifdef CONFIG_NF_CONNTRACK_PROCFS 155 /* Print out the private part of the conntrack. */ 156 static void sctp_print_conntrack(struct seq_file *s, struct nf_conn *ct) 157 { 158 seq_printf(s, "%s ", sctp_conntrack_names[ct->proto.sctp.state]); 159 } 160 #endif 161 162 #define for_each_sctp_chunk(skb, sch, _sch, offset, dataoff, count) \ 163 for ((offset) = (dataoff) + sizeof(struct sctphdr), (count) = 0; \ 164 (offset) < (skb)->len && \ 165 ((sch) = skb_header_pointer((skb), (offset), sizeof(_sch), &(_sch))); \ 166 (offset) += (ntohs((sch)->length) + 3) & ~3, (count)++) 167 168 /* Some validity checks to make sure the chunks are fine */ 169 static int do_basic_checks(struct nf_conn *ct, 170 const struct sk_buff *skb, 171 unsigned int dataoff, 172 unsigned long *map) 173 { 174 u_int32_t offset, count; 175 struct sctp_chunkhdr _sch, *sch; 176 int flag; 177 178 flag = 0; 179 180 for_each_sctp_chunk (skb, sch, _sch, offset, dataoff, count) { 181 pr_debug("Chunk Num: %d Type: %d\n", count, sch->type); 182 183 if (sch->type == SCTP_CID_INIT || 184 sch->type == SCTP_CID_INIT_ACK || 185 sch->type == SCTP_CID_SHUTDOWN_COMPLETE) 186 flag = 1; 187 188 /* 189 * Cookie Ack/Echo chunks not the first OR 190 * Init / Init Ack / Shutdown compl chunks not the only chunks 191 * OR zero-length. 192 */ 193 if (((sch->type == SCTP_CID_COOKIE_ACK || 194 sch->type == SCTP_CID_COOKIE_ECHO || 195 flag) && 196 count != 0) || !sch->length) { 197 pr_debug("Basic checks failed\n"); 198 return 1; 199 } 200 201 if (map) 202 set_bit(sch->type, map); 203 } 204 205 pr_debug("Basic checks passed\n"); 206 return count == 0; 207 } 208 209 static int sctp_new_state(enum ip_conntrack_dir dir, 210 enum sctp_conntrack cur_state, 211 int chunk_type) 212 { 213 int i; 214 215 pr_debug("Chunk type: %d\n", chunk_type); 216 217 switch (chunk_type) { 218 case SCTP_CID_INIT: 219 pr_debug("SCTP_CID_INIT\n"); 220 i = 0; 221 break; 222 case SCTP_CID_INIT_ACK: 223 pr_debug("SCTP_CID_INIT_ACK\n"); 224 i = 1; 225 break; 226 case SCTP_CID_ABORT: 227 pr_debug("SCTP_CID_ABORT\n"); 228 i = 2; 229 break; 230 case SCTP_CID_SHUTDOWN: 231 pr_debug("SCTP_CID_SHUTDOWN\n"); 232 i = 3; 233 break; 234 case SCTP_CID_SHUTDOWN_ACK: 235 pr_debug("SCTP_CID_SHUTDOWN_ACK\n"); 236 i = 4; 237 break; 238 case SCTP_CID_ERROR: 239 pr_debug("SCTP_CID_ERROR\n"); 240 i = 5; 241 break; 242 case SCTP_CID_COOKIE_ECHO: 243 pr_debug("SCTP_CID_COOKIE_ECHO\n"); 244 i = 6; 245 break; 246 case SCTP_CID_COOKIE_ACK: 247 pr_debug("SCTP_CID_COOKIE_ACK\n"); 248 i = 7; 249 break; 250 case SCTP_CID_SHUTDOWN_COMPLETE: 251 pr_debug("SCTP_CID_SHUTDOWN_COMPLETE\n"); 252 i = 8; 253 break; 254 case SCTP_CID_HEARTBEAT: 255 pr_debug("SCTP_CID_HEARTBEAT"); 256 i = 9; 257 break; 258 case SCTP_CID_HEARTBEAT_ACK: 259 pr_debug("SCTP_CID_HEARTBEAT_ACK"); 260 i = 10; 261 break; 262 default: 263 /* Other chunks like DATA or SACK do not change the state */ 264 pr_debug("Unknown chunk type, Will stay in %s\n", 265 sctp_conntrack_names[cur_state]); 266 return cur_state; 267 } 268 269 pr_debug("dir: %d cur_state: %s chunk_type: %d new_state: %s\n", 270 dir, sctp_conntrack_names[cur_state], chunk_type, 271 sctp_conntrack_names[sctp_conntracks[dir][i][cur_state]]); 272 273 return sctp_conntracks[dir][i][cur_state]; 274 } 275 276 /* Don't need lock here: this conntrack not in circulation yet */ 277 static noinline bool 278 sctp_new(struct nf_conn *ct, const struct sk_buff *skb, 279 const struct sctphdr *sh, unsigned int dataoff) 280 { 281 enum sctp_conntrack new_state; 282 const struct sctp_chunkhdr *sch; 283 struct sctp_chunkhdr _sch; 284 u32 offset, count; 285 286 memset(&ct->proto.sctp, 0, sizeof(ct->proto.sctp)); 287 new_state = SCTP_CONNTRACK_MAX; 288 for_each_sctp_chunk(skb, sch, _sch, offset, dataoff, count) { 289 new_state = sctp_new_state(IP_CT_DIR_ORIGINAL, 290 SCTP_CONNTRACK_NONE, sch->type); 291 292 /* Invalid: delete conntrack */ 293 if (new_state == SCTP_CONNTRACK_NONE || 294 new_state == SCTP_CONNTRACK_MAX) { 295 pr_debug("nf_conntrack_sctp: invalid new deleting.\n"); 296 return false; 297 } 298 299 /* Copy the vtag into the state info */ 300 if (sch->type == SCTP_CID_INIT) { 301 struct sctp_inithdr _inithdr, *ih; 302 /* Sec 8.5.1 (A) */ 303 if (sh->vtag) 304 return false; 305 306 ih = skb_header_pointer(skb, offset + sizeof(_sch), 307 sizeof(_inithdr), &_inithdr); 308 if (!ih) 309 return false; 310 311 pr_debug("Setting vtag %x for new conn\n", 312 ih->init_tag); 313 314 ct->proto.sctp.vtag[IP_CT_DIR_REPLY] = ih->init_tag; 315 } else if (sch->type == SCTP_CID_HEARTBEAT) { 316 pr_debug("Setting vtag %x for secondary conntrack\n", 317 sh->vtag); 318 ct->proto.sctp.vtag[IP_CT_DIR_ORIGINAL] = sh->vtag; 319 } else { 320 /* If it is a shutdown ack OOTB packet, we expect a return 321 shutdown complete, otherwise an ABORT Sec 8.4 (5) and (8) */ 322 pr_debug("Setting vtag %x for new conn OOTB\n", 323 sh->vtag); 324 ct->proto.sctp.vtag[IP_CT_DIR_REPLY] = sh->vtag; 325 } 326 327 ct->proto.sctp.state = new_state; 328 } 329 330 return true; 331 } 332 333 static bool sctp_error(struct sk_buff *skb, 334 unsigned int dataoff, 335 const struct nf_hook_state *state) 336 { 337 const struct sctphdr *sh; 338 const char *logmsg; 339 340 if (skb->len < dataoff + sizeof(struct sctphdr)) { 341 logmsg = "nf_ct_sctp: short packet "; 342 goto out_invalid; 343 } 344 if (state->hook == NF_INET_PRE_ROUTING && 345 state->net->ct.sysctl_checksum && 346 skb->ip_summed == CHECKSUM_NONE) { 347 if (!skb_make_writable(skb, dataoff + sizeof(struct sctphdr))) { 348 logmsg = "nf_ct_sctp: failed to read header "; 349 goto out_invalid; 350 } 351 sh = (const struct sctphdr *)(skb->data + dataoff); 352 if (sh->checksum != sctp_compute_cksum(skb, dataoff)) { 353 logmsg = "nf_ct_sctp: bad CRC "; 354 goto out_invalid; 355 } 356 skb->ip_summed = CHECKSUM_UNNECESSARY; 357 } 358 return false; 359 out_invalid: 360 nf_l4proto_log_invalid(skb, state->net, state->pf, IPPROTO_SCTP, "%s", logmsg); 361 return true; 362 } 363 364 /* Returns verdict for packet, or -NF_ACCEPT for invalid. */ 365 static int sctp_packet(struct nf_conn *ct, 366 struct sk_buff *skb, 367 unsigned int dataoff, 368 enum ip_conntrack_info ctinfo, 369 const struct nf_hook_state *state) 370 { 371 enum sctp_conntrack new_state, old_state; 372 enum ip_conntrack_dir dir = CTINFO2DIR(ctinfo); 373 const struct sctphdr *sh; 374 struct sctphdr _sctph; 375 const struct sctp_chunkhdr *sch; 376 struct sctp_chunkhdr _sch; 377 u_int32_t offset, count; 378 unsigned int *timeouts; 379 unsigned long map[256 / sizeof(unsigned long)] = { 0 }; 380 381 if (sctp_error(skb, dataoff, state)) 382 return -NF_ACCEPT; 383 384 sh = skb_header_pointer(skb, dataoff, sizeof(_sctph), &_sctph); 385 if (sh == NULL) 386 goto out; 387 388 if (do_basic_checks(ct, skb, dataoff, map) != 0) 389 goto out; 390 391 if (!nf_ct_is_confirmed(ct)) { 392 /* If an OOTB packet has any of these chunks discard (Sec 8.4) */ 393 if (test_bit(SCTP_CID_ABORT, map) || 394 test_bit(SCTP_CID_SHUTDOWN_COMPLETE, map) || 395 test_bit(SCTP_CID_COOKIE_ACK, map)) 396 return -NF_ACCEPT; 397 398 if (!sctp_new(ct, skb, sh, dataoff)) 399 return -NF_ACCEPT; 400 } 401 402 /* Check the verification tag (Sec 8.5) */ 403 if (!test_bit(SCTP_CID_INIT, map) && 404 !test_bit(SCTP_CID_SHUTDOWN_COMPLETE, map) && 405 !test_bit(SCTP_CID_COOKIE_ECHO, map) && 406 !test_bit(SCTP_CID_ABORT, map) && 407 !test_bit(SCTP_CID_SHUTDOWN_ACK, map) && 408 !test_bit(SCTP_CID_HEARTBEAT, map) && 409 !test_bit(SCTP_CID_HEARTBEAT_ACK, map) && 410 sh->vtag != ct->proto.sctp.vtag[dir]) { 411 pr_debug("Verification tag check failed\n"); 412 goto out; 413 } 414 415 old_state = new_state = SCTP_CONNTRACK_NONE; 416 spin_lock_bh(&ct->lock); 417 for_each_sctp_chunk (skb, sch, _sch, offset, dataoff, count) { 418 /* Special cases of Verification tag check (Sec 8.5.1) */ 419 if (sch->type == SCTP_CID_INIT) { 420 /* Sec 8.5.1 (A) */ 421 if (sh->vtag != 0) 422 goto out_unlock; 423 } else if (sch->type == SCTP_CID_ABORT) { 424 /* Sec 8.5.1 (B) */ 425 if (sh->vtag != ct->proto.sctp.vtag[dir] && 426 sh->vtag != ct->proto.sctp.vtag[!dir]) 427 goto out_unlock; 428 } else if (sch->type == SCTP_CID_SHUTDOWN_COMPLETE) { 429 /* Sec 8.5.1 (C) */ 430 if (sh->vtag != ct->proto.sctp.vtag[dir] && 431 sh->vtag != ct->proto.sctp.vtag[!dir] && 432 sch->flags & SCTP_CHUNK_FLAG_T) 433 goto out_unlock; 434 } else if (sch->type == SCTP_CID_COOKIE_ECHO) { 435 /* Sec 8.5.1 (D) */ 436 if (sh->vtag != ct->proto.sctp.vtag[dir]) 437 goto out_unlock; 438 } else if (sch->type == SCTP_CID_HEARTBEAT || 439 sch->type == SCTP_CID_HEARTBEAT_ACK) { 440 if (ct->proto.sctp.vtag[dir] == 0) { 441 pr_debug("Setting vtag %x for dir %d\n", 442 sh->vtag, dir); 443 ct->proto.sctp.vtag[dir] = sh->vtag; 444 } else if (sh->vtag != ct->proto.sctp.vtag[dir]) { 445 pr_debug("Verification tag check failed\n"); 446 goto out_unlock; 447 } 448 } 449 450 old_state = ct->proto.sctp.state; 451 new_state = sctp_new_state(dir, old_state, sch->type); 452 453 /* Invalid */ 454 if (new_state == SCTP_CONNTRACK_MAX) { 455 pr_debug("nf_conntrack_sctp: Invalid dir=%i ctype=%u " 456 "conntrack=%u\n", 457 dir, sch->type, old_state); 458 goto out_unlock; 459 } 460 461 /* If it is an INIT or an INIT ACK note down the vtag */ 462 if (sch->type == SCTP_CID_INIT || 463 sch->type == SCTP_CID_INIT_ACK) { 464 struct sctp_inithdr _inithdr, *ih; 465 466 ih = skb_header_pointer(skb, offset + sizeof(_sch), 467 sizeof(_inithdr), &_inithdr); 468 if (ih == NULL) 469 goto out_unlock; 470 pr_debug("Setting vtag %x for dir %d\n", 471 ih->init_tag, !dir); 472 ct->proto.sctp.vtag[!dir] = ih->init_tag; 473 } 474 475 ct->proto.sctp.state = new_state; 476 if (old_state != new_state) 477 nf_conntrack_event_cache(IPCT_PROTOINFO, ct); 478 } 479 spin_unlock_bh(&ct->lock); 480 481 timeouts = nf_ct_timeout_lookup(ct); 482 if (!timeouts) 483 timeouts = sctp_pernet(nf_ct_net(ct))->timeouts; 484 485 nf_ct_refresh_acct(ct, ctinfo, skb, timeouts[new_state]); 486 487 if (old_state == SCTP_CONNTRACK_COOKIE_ECHOED && 488 dir == IP_CT_DIR_REPLY && 489 new_state == SCTP_CONNTRACK_ESTABLISHED) { 490 pr_debug("Setting assured bit\n"); 491 set_bit(IPS_ASSURED_BIT, &ct->status); 492 nf_conntrack_event_cache(IPCT_ASSURED, ct); 493 } 494 495 return NF_ACCEPT; 496 497 out_unlock: 498 spin_unlock_bh(&ct->lock); 499 out: 500 return -NF_ACCEPT; 501 } 502 503 static bool sctp_can_early_drop(const struct nf_conn *ct) 504 { 505 switch (ct->proto.sctp.state) { 506 case SCTP_CONNTRACK_SHUTDOWN_SENT: 507 case SCTP_CONNTRACK_SHUTDOWN_RECD: 508 case SCTP_CONNTRACK_SHUTDOWN_ACK_SENT: 509 return true; 510 default: 511 break; 512 } 513 514 return false; 515 } 516 517 #if IS_ENABLED(CONFIG_NF_CT_NETLINK) 518 519 #include <linux/netfilter/nfnetlink.h> 520 #include <linux/netfilter/nfnetlink_conntrack.h> 521 522 static int sctp_to_nlattr(struct sk_buff *skb, struct nlattr *nla, 523 struct nf_conn *ct) 524 { 525 struct nlattr *nest_parms; 526 527 spin_lock_bh(&ct->lock); 528 nest_parms = nla_nest_start(skb, CTA_PROTOINFO_SCTP | NLA_F_NESTED); 529 if (!nest_parms) 530 goto nla_put_failure; 531 532 if (nla_put_u8(skb, CTA_PROTOINFO_SCTP_STATE, ct->proto.sctp.state) || 533 nla_put_be32(skb, CTA_PROTOINFO_SCTP_VTAG_ORIGINAL, 534 ct->proto.sctp.vtag[IP_CT_DIR_ORIGINAL]) || 535 nla_put_be32(skb, CTA_PROTOINFO_SCTP_VTAG_REPLY, 536 ct->proto.sctp.vtag[IP_CT_DIR_REPLY])) 537 goto nla_put_failure; 538 539 spin_unlock_bh(&ct->lock); 540 541 nla_nest_end(skb, nest_parms); 542 543 return 0; 544 545 nla_put_failure: 546 spin_unlock_bh(&ct->lock); 547 return -1; 548 } 549 550 static const struct nla_policy sctp_nla_policy[CTA_PROTOINFO_SCTP_MAX+1] = { 551 [CTA_PROTOINFO_SCTP_STATE] = { .type = NLA_U8 }, 552 [CTA_PROTOINFO_SCTP_VTAG_ORIGINAL] = { .type = NLA_U32 }, 553 [CTA_PROTOINFO_SCTP_VTAG_REPLY] = { .type = NLA_U32 }, 554 }; 555 556 #define SCTP_NLATTR_SIZE ( \ 557 NLA_ALIGN(NLA_HDRLEN + 1) + \ 558 NLA_ALIGN(NLA_HDRLEN + 4) + \ 559 NLA_ALIGN(NLA_HDRLEN + 4)) 560 561 static int nlattr_to_sctp(struct nlattr *cda[], struct nf_conn *ct) 562 { 563 struct nlattr *attr = cda[CTA_PROTOINFO_SCTP]; 564 struct nlattr *tb[CTA_PROTOINFO_SCTP_MAX+1]; 565 int err; 566 567 /* updates may not contain the internal protocol info, skip parsing */ 568 if (!attr) 569 return 0; 570 571 err = nla_parse_nested(tb, CTA_PROTOINFO_SCTP_MAX, attr, 572 sctp_nla_policy, NULL); 573 if (err < 0) 574 return err; 575 576 if (!tb[CTA_PROTOINFO_SCTP_STATE] || 577 !tb[CTA_PROTOINFO_SCTP_VTAG_ORIGINAL] || 578 !tb[CTA_PROTOINFO_SCTP_VTAG_REPLY]) 579 return -EINVAL; 580 581 spin_lock_bh(&ct->lock); 582 ct->proto.sctp.state = nla_get_u8(tb[CTA_PROTOINFO_SCTP_STATE]); 583 ct->proto.sctp.vtag[IP_CT_DIR_ORIGINAL] = 584 nla_get_be32(tb[CTA_PROTOINFO_SCTP_VTAG_ORIGINAL]); 585 ct->proto.sctp.vtag[IP_CT_DIR_REPLY] = 586 nla_get_be32(tb[CTA_PROTOINFO_SCTP_VTAG_REPLY]); 587 spin_unlock_bh(&ct->lock); 588 589 return 0; 590 } 591 #endif 592 593 #ifdef CONFIG_NF_CONNTRACK_TIMEOUT 594 595 #include <linux/netfilter/nfnetlink.h> 596 #include <linux/netfilter/nfnetlink_cttimeout.h> 597 598 static int sctp_timeout_nlattr_to_obj(struct nlattr *tb[], 599 struct net *net, void *data) 600 { 601 unsigned int *timeouts = data; 602 struct nf_sctp_net *sn = sctp_pernet(net); 603 int i; 604 605 /* set default SCTP timeouts. */ 606 for (i=0; i<SCTP_CONNTRACK_MAX; i++) 607 timeouts[i] = sn->timeouts[i]; 608 609 /* there's a 1:1 mapping between attributes and protocol states. */ 610 for (i=CTA_TIMEOUT_SCTP_UNSPEC+1; i<CTA_TIMEOUT_SCTP_MAX+1; i++) { 611 if (tb[i]) { 612 timeouts[i] = ntohl(nla_get_be32(tb[i])) * HZ; 613 } 614 } 615 616 timeouts[CTA_TIMEOUT_SCTP_UNSPEC] = timeouts[CTA_TIMEOUT_SCTP_CLOSED]; 617 return 0; 618 } 619 620 static int 621 sctp_timeout_obj_to_nlattr(struct sk_buff *skb, const void *data) 622 { 623 const unsigned int *timeouts = data; 624 int i; 625 626 for (i=CTA_TIMEOUT_SCTP_UNSPEC+1; i<CTA_TIMEOUT_SCTP_MAX+1; i++) { 627 if (nla_put_be32(skb, i, htonl(timeouts[i] / HZ))) 628 goto nla_put_failure; 629 } 630 return 0; 631 632 nla_put_failure: 633 return -ENOSPC; 634 } 635 636 static const struct nla_policy 637 sctp_timeout_nla_policy[CTA_TIMEOUT_SCTP_MAX+1] = { 638 [CTA_TIMEOUT_SCTP_CLOSED] = { .type = NLA_U32 }, 639 [CTA_TIMEOUT_SCTP_COOKIE_WAIT] = { .type = NLA_U32 }, 640 [CTA_TIMEOUT_SCTP_COOKIE_ECHOED] = { .type = NLA_U32 }, 641 [CTA_TIMEOUT_SCTP_ESTABLISHED] = { .type = NLA_U32 }, 642 [CTA_TIMEOUT_SCTP_SHUTDOWN_SENT] = { .type = NLA_U32 }, 643 [CTA_TIMEOUT_SCTP_SHUTDOWN_RECD] = { .type = NLA_U32 }, 644 [CTA_TIMEOUT_SCTP_SHUTDOWN_ACK_SENT] = { .type = NLA_U32 }, 645 [CTA_TIMEOUT_SCTP_HEARTBEAT_SENT] = { .type = NLA_U32 }, 646 [CTA_TIMEOUT_SCTP_HEARTBEAT_ACKED] = { .type = NLA_U32 }, 647 }; 648 #endif /* CONFIG_NF_CONNTRACK_TIMEOUT */ 649 650 651 #ifdef CONFIG_SYSCTL 652 static struct ctl_table sctp_sysctl_table[] = { 653 { 654 .procname = "nf_conntrack_sctp_timeout_closed", 655 .maxlen = sizeof(unsigned int), 656 .mode = 0644, 657 .proc_handler = proc_dointvec_jiffies, 658 }, 659 { 660 .procname = "nf_conntrack_sctp_timeout_cookie_wait", 661 .maxlen = sizeof(unsigned int), 662 .mode = 0644, 663 .proc_handler = proc_dointvec_jiffies, 664 }, 665 { 666 .procname = "nf_conntrack_sctp_timeout_cookie_echoed", 667 .maxlen = sizeof(unsigned int), 668 .mode = 0644, 669 .proc_handler = proc_dointvec_jiffies, 670 }, 671 { 672 .procname = "nf_conntrack_sctp_timeout_established", 673 .maxlen = sizeof(unsigned int), 674 .mode = 0644, 675 .proc_handler = proc_dointvec_jiffies, 676 }, 677 { 678 .procname = "nf_conntrack_sctp_timeout_shutdown_sent", 679 .maxlen = sizeof(unsigned int), 680 .mode = 0644, 681 .proc_handler = proc_dointvec_jiffies, 682 }, 683 { 684 .procname = "nf_conntrack_sctp_timeout_shutdown_recd", 685 .maxlen = sizeof(unsigned int), 686 .mode = 0644, 687 .proc_handler = proc_dointvec_jiffies, 688 }, 689 { 690 .procname = "nf_conntrack_sctp_timeout_shutdown_ack_sent", 691 .maxlen = sizeof(unsigned int), 692 .mode = 0644, 693 .proc_handler = proc_dointvec_jiffies, 694 }, 695 { 696 .procname = "nf_conntrack_sctp_timeout_heartbeat_sent", 697 .maxlen = sizeof(unsigned int), 698 .mode = 0644, 699 .proc_handler = proc_dointvec_jiffies, 700 }, 701 { 702 .procname = "nf_conntrack_sctp_timeout_heartbeat_acked", 703 .maxlen = sizeof(unsigned int), 704 .mode = 0644, 705 .proc_handler = proc_dointvec_jiffies, 706 }, 707 { } 708 }; 709 #endif 710 711 static int sctp_kmemdup_sysctl_table(struct nf_proto_net *pn, 712 struct nf_sctp_net *sn) 713 { 714 #ifdef CONFIG_SYSCTL 715 if (pn->ctl_table) 716 return 0; 717 718 pn->ctl_table = kmemdup(sctp_sysctl_table, 719 sizeof(sctp_sysctl_table), 720 GFP_KERNEL); 721 if (!pn->ctl_table) 722 return -ENOMEM; 723 724 pn->ctl_table[0].data = &sn->timeouts[SCTP_CONNTRACK_CLOSED]; 725 pn->ctl_table[1].data = &sn->timeouts[SCTP_CONNTRACK_COOKIE_WAIT]; 726 pn->ctl_table[2].data = &sn->timeouts[SCTP_CONNTRACK_COOKIE_ECHOED]; 727 pn->ctl_table[3].data = &sn->timeouts[SCTP_CONNTRACK_ESTABLISHED]; 728 pn->ctl_table[4].data = &sn->timeouts[SCTP_CONNTRACK_SHUTDOWN_SENT]; 729 pn->ctl_table[5].data = &sn->timeouts[SCTP_CONNTRACK_SHUTDOWN_RECD]; 730 pn->ctl_table[6].data = &sn->timeouts[SCTP_CONNTRACK_SHUTDOWN_ACK_SENT]; 731 pn->ctl_table[7].data = &sn->timeouts[SCTP_CONNTRACK_HEARTBEAT_SENT]; 732 pn->ctl_table[8].data = &sn->timeouts[SCTP_CONNTRACK_HEARTBEAT_ACKED]; 733 #endif 734 return 0; 735 } 736 737 static int sctp_init_net(struct net *net, u_int16_t proto) 738 { 739 struct nf_sctp_net *sn = sctp_pernet(net); 740 struct nf_proto_net *pn = &sn->pn; 741 742 if (!pn->users) { 743 int i; 744 745 for (i = 0; i < SCTP_CONNTRACK_MAX; i++) 746 sn->timeouts[i] = sctp_timeouts[i]; 747 748 /* timeouts[0] is unused, init it so ->timeouts[0] contains 749 * 'new' timeout, like udp or icmp. 750 */ 751 sn->timeouts[0] = sctp_timeouts[SCTP_CONNTRACK_CLOSED]; 752 } 753 754 return sctp_kmemdup_sysctl_table(pn, sn); 755 } 756 757 static struct nf_proto_net *sctp_get_net_proto(struct net *net) 758 { 759 return &net->ct.nf_ct_proto.sctp.pn; 760 } 761 762 const struct nf_conntrack_l4proto nf_conntrack_l4proto_sctp4 = { 763 .l3proto = PF_INET, 764 .l4proto = IPPROTO_SCTP, 765 #ifdef CONFIG_NF_CONNTRACK_PROCFS 766 .print_conntrack = sctp_print_conntrack, 767 #endif 768 .packet = sctp_packet, 769 .can_early_drop = sctp_can_early_drop, 770 .me = THIS_MODULE, 771 #if IS_ENABLED(CONFIG_NF_CT_NETLINK) 772 .nlattr_size = SCTP_NLATTR_SIZE, 773 .to_nlattr = sctp_to_nlattr, 774 .from_nlattr = nlattr_to_sctp, 775 .tuple_to_nlattr = nf_ct_port_tuple_to_nlattr, 776 .nlattr_tuple_size = nf_ct_port_nlattr_tuple_size, 777 .nlattr_to_tuple = nf_ct_port_nlattr_to_tuple, 778 .nla_policy = nf_ct_port_nla_policy, 779 #endif 780 #ifdef CONFIG_NF_CONNTRACK_TIMEOUT 781 .ctnl_timeout = { 782 .nlattr_to_obj = sctp_timeout_nlattr_to_obj, 783 .obj_to_nlattr = sctp_timeout_obj_to_nlattr, 784 .nlattr_max = CTA_TIMEOUT_SCTP_MAX, 785 .obj_size = sizeof(unsigned int) * SCTP_CONNTRACK_MAX, 786 .nla_policy = sctp_timeout_nla_policy, 787 }, 788 #endif /* CONFIG_NF_CONNTRACK_TIMEOUT */ 789 .init_net = sctp_init_net, 790 .get_net_proto = sctp_get_net_proto, 791 }; 792 EXPORT_SYMBOL_GPL(nf_conntrack_l4proto_sctp4); 793 794 const struct nf_conntrack_l4proto nf_conntrack_l4proto_sctp6 = { 795 .l3proto = PF_INET6, 796 .l4proto = IPPROTO_SCTP, 797 #ifdef CONFIG_NF_CONNTRACK_PROCFS 798 .print_conntrack = sctp_print_conntrack, 799 #endif 800 .packet = sctp_packet, 801 .can_early_drop = sctp_can_early_drop, 802 .me = THIS_MODULE, 803 #if IS_ENABLED(CONFIG_NF_CT_NETLINK) 804 .nlattr_size = SCTP_NLATTR_SIZE, 805 .to_nlattr = sctp_to_nlattr, 806 .from_nlattr = nlattr_to_sctp, 807 .tuple_to_nlattr = nf_ct_port_tuple_to_nlattr, 808 .nlattr_tuple_size = nf_ct_port_nlattr_tuple_size, 809 .nlattr_to_tuple = nf_ct_port_nlattr_to_tuple, 810 .nla_policy = nf_ct_port_nla_policy, 811 #endif 812 #ifdef CONFIG_NF_CONNTRACK_TIMEOUT 813 .ctnl_timeout = { 814 .nlattr_to_obj = sctp_timeout_nlattr_to_obj, 815 .obj_to_nlattr = sctp_timeout_obj_to_nlattr, 816 .nlattr_max = CTA_TIMEOUT_SCTP_MAX, 817 .obj_size = sizeof(unsigned int) * SCTP_CONNTRACK_MAX, 818 .nla_policy = sctp_timeout_nla_policy, 819 }, 820 #endif /* CONFIG_NF_CONNTRACK_TIMEOUT */ 821 .init_net = sctp_init_net, 822 .get_net_proto = sctp_get_net_proto, 823 }; 824 EXPORT_SYMBOL_GPL(nf_conntrack_l4proto_sctp6); 825