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 /* Returns verdict for packet, or -NF_ACCEPT for invalid. */ 277 static int sctp_packet(struct nf_conn *ct, 278 const struct sk_buff *skb, 279 unsigned int dataoff, 280 enum ip_conntrack_info ctinfo) 281 { 282 enum sctp_conntrack new_state, old_state; 283 enum ip_conntrack_dir dir = CTINFO2DIR(ctinfo); 284 const struct sctphdr *sh; 285 struct sctphdr _sctph; 286 const struct sctp_chunkhdr *sch; 287 struct sctp_chunkhdr _sch; 288 u_int32_t offset, count; 289 unsigned int *timeouts; 290 unsigned long map[256 / sizeof(unsigned long)] = { 0 }; 291 292 sh = skb_header_pointer(skb, dataoff, sizeof(_sctph), &_sctph); 293 if (sh == NULL) 294 goto out; 295 296 if (do_basic_checks(ct, skb, dataoff, map) != 0) 297 goto out; 298 299 /* Check the verification tag (Sec 8.5) */ 300 if (!test_bit(SCTP_CID_INIT, map) && 301 !test_bit(SCTP_CID_SHUTDOWN_COMPLETE, map) && 302 !test_bit(SCTP_CID_COOKIE_ECHO, map) && 303 !test_bit(SCTP_CID_ABORT, map) && 304 !test_bit(SCTP_CID_SHUTDOWN_ACK, map) && 305 !test_bit(SCTP_CID_HEARTBEAT, map) && 306 !test_bit(SCTP_CID_HEARTBEAT_ACK, map) && 307 sh->vtag != ct->proto.sctp.vtag[dir]) { 308 pr_debug("Verification tag check failed\n"); 309 goto out; 310 } 311 312 old_state = new_state = SCTP_CONNTRACK_NONE; 313 spin_lock_bh(&ct->lock); 314 for_each_sctp_chunk (skb, sch, _sch, offset, dataoff, count) { 315 /* Special cases of Verification tag check (Sec 8.5.1) */ 316 if (sch->type == SCTP_CID_INIT) { 317 /* Sec 8.5.1 (A) */ 318 if (sh->vtag != 0) 319 goto out_unlock; 320 } else if (sch->type == SCTP_CID_ABORT) { 321 /* Sec 8.5.1 (B) */ 322 if (sh->vtag != ct->proto.sctp.vtag[dir] && 323 sh->vtag != ct->proto.sctp.vtag[!dir]) 324 goto out_unlock; 325 } else if (sch->type == SCTP_CID_SHUTDOWN_COMPLETE) { 326 /* Sec 8.5.1 (C) */ 327 if (sh->vtag != ct->proto.sctp.vtag[dir] && 328 sh->vtag != ct->proto.sctp.vtag[!dir] && 329 sch->flags & SCTP_CHUNK_FLAG_T) 330 goto out_unlock; 331 } else if (sch->type == SCTP_CID_COOKIE_ECHO) { 332 /* Sec 8.5.1 (D) */ 333 if (sh->vtag != ct->proto.sctp.vtag[dir]) 334 goto out_unlock; 335 } else if (sch->type == SCTP_CID_HEARTBEAT || 336 sch->type == SCTP_CID_HEARTBEAT_ACK) { 337 if (ct->proto.sctp.vtag[dir] == 0) { 338 pr_debug("Setting vtag %x for dir %d\n", 339 sh->vtag, dir); 340 ct->proto.sctp.vtag[dir] = sh->vtag; 341 } else if (sh->vtag != ct->proto.sctp.vtag[dir]) { 342 pr_debug("Verification tag check failed\n"); 343 goto out_unlock; 344 } 345 } 346 347 old_state = ct->proto.sctp.state; 348 new_state = sctp_new_state(dir, old_state, sch->type); 349 350 /* Invalid */ 351 if (new_state == SCTP_CONNTRACK_MAX) { 352 pr_debug("nf_conntrack_sctp: Invalid dir=%i ctype=%u " 353 "conntrack=%u\n", 354 dir, sch->type, old_state); 355 goto out_unlock; 356 } 357 358 /* If it is an INIT or an INIT ACK note down the vtag */ 359 if (sch->type == SCTP_CID_INIT || 360 sch->type == SCTP_CID_INIT_ACK) { 361 struct sctp_inithdr _inithdr, *ih; 362 363 ih = skb_header_pointer(skb, offset + sizeof(_sch), 364 sizeof(_inithdr), &_inithdr); 365 if (ih == NULL) 366 goto out_unlock; 367 pr_debug("Setting vtag %x for dir %d\n", 368 ih->init_tag, !dir); 369 ct->proto.sctp.vtag[!dir] = ih->init_tag; 370 } 371 372 ct->proto.sctp.state = new_state; 373 if (old_state != new_state) 374 nf_conntrack_event_cache(IPCT_PROTOINFO, ct); 375 } 376 spin_unlock_bh(&ct->lock); 377 378 timeouts = nf_ct_timeout_lookup(ct); 379 if (!timeouts) 380 timeouts = sctp_pernet(nf_ct_net(ct))->timeouts; 381 382 nf_ct_refresh_acct(ct, ctinfo, skb, timeouts[new_state]); 383 384 if (old_state == SCTP_CONNTRACK_COOKIE_ECHOED && 385 dir == IP_CT_DIR_REPLY && 386 new_state == SCTP_CONNTRACK_ESTABLISHED) { 387 pr_debug("Setting assured bit\n"); 388 set_bit(IPS_ASSURED_BIT, &ct->status); 389 nf_conntrack_event_cache(IPCT_ASSURED, ct); 390 } 391 392 return NF_ACCEPT; 393 394 out_unlock: 395 spin_unlock_bh(&ct->lock); 396 out: 397 return -NF_ACCEPT; 398 } 399 400 /* Called when a new connection for this protocol found. */ 401 static bool sctp_new(struct nf_conn *ct, const struct sk_buff *skb, 402 unsigned int dataoff) 403 { 404 enum sctp_conntrack new_state; 405 const struct sctphdr *sh; 406 struct sctphdr _sctph; 407 const struct sctp_chunkhdr *sch; 408 struct sctp_chunkhdr _sch; 409 u_int32_t offset, count; 410 unsigned long map[256 / sizeof(unsigned long)] = { 0 }; 411 412 sh = skb_header_pointer(skb, dataoff, sizeof(_sctph), &_sctph); 413 if (sh == NULL) 414 return false; 415 416 if (do_basic_checks(ct, skb, dataoff, map) != 0) 417 return false; 418 419 /* If an OOTB packet has any of these chunks discard (Sec 8.4) */ 420 if (test_bit(SCTP_CID_ABORT, map) || 421 test_bit(SCTP_CID_SHUTDOWN_COMPLETE, map) || 422 test_bit(SCTP_CID_COOKIE_ACK, map)) 423 return false; 424 425 memset(&ct->proto.sctp, 0, sizeof(ct->proto.sctp)); 426 new_state = SCTP_CONNTRACK_MAX; 427 for_each_sctp_chunk (skb, sch, _sch, offset, dataoff, count) { 428 /* Don't need lock here: this conntrack not in circulation yet */ 429 new_state = sctp_new_state(IP_CT_DIR_ORIGINAL, 430 SCTP_CONNTRACK_NONE, sch->type); 431 432 /* Invalid: delete conntrack */ 433 if (new_state == SCTP_CONNTRACK_NONE || 434 new_state == SCTP_CONNTRACK_MAX) { 435 pr_debug("nf_conntrack_sctp: invalid new deleting.\n"); 436 return false; 437 } 438 439 /* Copy the vtag into the state info */ 440 if (sch->type == SCTP_CID_INIT) { 441 struct sctp_inithdr _inithdr, *ih; 442 /* Sec 8.5.1 (A) */ 443 if (sh->vtag) 444 return false; 445 446 ih = skb_header_pointer(skb, offset + sizeof(_sch), 447 sizeof(_inithdr), &_inithdr); 448 if (!ih) 449 return false; 450 451 pr_debug("Setting vtag %x for new conn\n", 452 ih->init_tag); 453 454 ct->proto.sctp.vtag[IP_CT_DIR_REPLY] = ih->init_tag; 455 } else if (sch->type == SCTP_CID_HEARTBEAT) { 456 pr_debug("Setting vtag %x for secondary conntrack\n", 457 sh->vtag); 458 ct->proto.sctp.vtag[IP_CT_DIR_ORIGINAL] = sh->vtag; 459 } 460 /* If it is a shutdown ack OOTB packet, we expect a return 461 shutdown complete, otherwise an ABORT Sec 8.4 (5) and (8) */ 462 else { 463 pr_debug("Setting vtag %x for new conn OOTB\n", 464 sh->vtag); 465 ct->proto.sctp.vtag[IP_CT_DIR_REPLY] = sh->vtag; 466 } 467 468 ct->proto.sctp.state = new_state; 469 } 470 471 return true; 472 } 473 474 static int sctp_error(struct net *net, struct nf_conn *tpl, struct sk_buff *skb, 475 unsigned int dataoff, 476 u8 pf, unsigned int hooknum) 477 { 478 const struct sctphdr *sh; 479 const char *logmsg; 480 481 if (skb->len < dataoff + sizeof(struct sctphdr)) { 482 logmsg = "nf_ct_sctp: short packet "; 483 goto out_invalid; 484 } 485 if (net->ct.sysctl_checksum && hooknum == NF_INET_PRE_ROUTING && 486 skb->ip_summed == CHECKSUM_NONE) { 487 if (!skb_make_writable(skb, dataoff + sizeof(struct sctphdr))) { 488 logmsg = "nf_ct_sctp: failed to read header "; 489 goto out_invalid; 490 } 491 sh = (const struct sctphdr *)(skb->data + dataoff); 492 if (sh->checksum != sctp_compute_cksum(skb, dataoff)) { 493 logmsg = "nf_ct_sctp: bad CRC "; 494 goto out_invalid; 495 } 496 skb->ip_summed = CHECKSUM_UNNECESSARY; 497 } 498 return NF_ACCEPT; 499 out_invalid: 500 nf_l4proto_log_invalid(skb, net, pf, IPPROTO_SCTP, "%s", logmsg); 501 return -NF_ACCEPT; 502 } 503 504 static bool sctp_can_early_drop(const struct nf_conn *ct) 505 { 506 switch (ct->proto.sctp.state) { 507 case SCTP_CONNTRACK_SHUTDOWN_SENT: 508 case SCTP_CONNTRACK_SHUTDOWN_RECD: 509 case SCTP_CONNTRACK_SHUTDOWN_ACK_SENT: 510 return true; 511 default: 512 break; 513 } 514 515 return false; 516 } 517 518 #if IS_ENABLED(CONFIG_NF_CT_NETLINK) 519 520 #include <linux/netfilter/nfnetlink.h> 521 #include <linux/netfilter/nfnetlink_conntrack.h> 522 523 static int sctp_to_nlattr(struct sk_buff *skb, struct nlattr *nla, 524 struct nf_conn *ct) 525 { 526 struct nlattr *nest_parms; 527 528 spin_lock_bh(&ct->lock); 529 nest_parms = nla_nest_start(skb, CTA_PROTOINFO_SCTP | NLA_F_NESTED); 530 if (!nest_parms) 531 goto nla_put_failure; 532 533 if (nla_put_u8(skb, CTA_PROTOINFO_SCTP_STATE, ct->proto.sctp.state) || 534 nla_put_be32(skb, CTA_PROTOINFO_SCTP_VTAG_ORIGINAL, 535 ct->proto.sctp.vtag[IP_CT_DIR_ORIGINAL]) || 536 nla_put_be32(skb, CTA_PROTOINFO_SCTP_VTAG_REPLY, 537 ct->proto.sctp.vtag[IP_CT_DIR_REPLY])) 538 goto nla_put_failure; 539 540 spin_unlock_bh(&ct->lock); 541 542 nla_nest_end(skb, nest_parms); 543 544 return 0; 545 546 nla_put_failure: 547 spin_unlock_bh(&ct->lock); 548 return -1; 549 } 550 551 static const struct nla_policy sctp_nla_policy[CTA_PROTOINFO_SCTP_MAX+1] = { 552 [CTA_PROTOINFO_SCTP_STATE] = { .type = NLA_U8 }, 553 [CTA_PROTOINFO_SCTP_VTAG_ORIGINAL] = { .type = NLA_U32 }, 554 [CTA_PROTOINFO_SCTP_VTAG_REPLY] = { .type = NLA_U32 }, 555 }; 556 557 #define SCTP_NLATTR_SIZE ( \ 558 NLA_ALIGN(NLA_HDRLEN + 1) + \ 559 NLA_ALIGN(NLA_HDRLEN + 4) + \ 560 NLA_ALIGN(NLA_HDRLEN + 4)) 561 562 static int nlattr_to_sctp(struct nlattr *cda[], struct nf_conn *ct) 563 { 564 struct nlattr *attr = cda[CTA_PROTOINFO_SCTP]; 565 struct nlattr *tb[CTA_PROTOINFO_SCTP_MAX+1]; 566 int err; 567 568 /* updates may not contain the internal protocol info, skip parsing */ 569 if (!attr) 570 return 0; 571 572 err = nla_parse_nested(tb, CTA_PROTOINFO_SCTP_MAX, attr, 573 sctp_nla_policy, NULL); 574 if (err < 0) 575 return err; 576 577 if (!tb[CTA_PROTOINFO_SCTP_STATE] || 578 !tb[CTA_PROTOINFO_SCTP_VTAG_ORIGINAL] || 579 !tb[CTA_PROTOINFO_SCTP_VTAG_REPLY]) 580 return -EINVAL; 581 582 spin_lock_bh(&ct->lock); 583 ct->proto.sctp.state = nla_get_u8(tb[CTA_PROTOINFO_SCTP_STATE]); 584 ct->proto.sctp.vtag[IP_CT_DIR_ORIGINAL] = 585 nla_get_be32(tb[CTA_PROTOINFO_SCTP_VTAG_ORIGINAL]); 586 ct->proto.sctp.vtag[IP_CT_DIR_REPLY] = 587 nla_get_be32(tb[CTA_PROTOINFO_SCTP_VTAG_REPLY]); 588 spin_unlock_bh(&ct->lock); 589 590 return 0; 591 } 592 #endif 593 594 #ifdef CONFIG_NF_CONNTRACK_TIMEOUT 595 596 #include <linux/netfilter/nfnetlink.h> 597 #include <linux/netfilter/nfnetlink_cttimeout.h> 598 599 static int sctp_timeout_nlattr_to_obj(struct nlattr *tb[], 600 struct net *net, void *data) 601 { 602 unsigned int *timeouts = data; 603 struct nf_sctp_net *sn = sctp_pernet(net); 604 int i; 605 606 /* set default SCTP timeouts. */ 607 for (i=0; i<SCTP_CONNTRACK_MAX; i++) 608 timeouts[i] = sn->timeouts[i]; 609 610 /* there's a 1:1 mapping between attributes and protocol states. */ 611 for (i=CTA_TIMEOUT_SCTP_UNSPEC+1; i<CTA_TIMEOUT_SCTP_MAX+1; i++) { 612 if (tb[i]) { 613 timeouts[i] = ntohl(nla_get_be32(tb[i])) * HZ; 614 } 615 } 616 617 timeouts[CTA_TIMEOUT_SCTP_UNSPEC] = timeouts[CTA_TIMEOUT_SCTP_CLOSED]; 618 return 0; 619 } 620 621 static int 622 sctp_timeout_obj_to_nlattr(struct sk_buff *skb, const void *data) 623 { 624 const unsigned int *timeouts = data; 625 int i; 626 627 for (i=CTA_TIMEOUT_SCTP_UNSPEC+1; i<CTA_TIMEOUT_SCTP_MAX+1; i++) { 628 if (nla_put_be32(skb, i, htonl(timeouts[i] / HZ))) 629 goto nla_put_failure; 630 } 631 return 0; 632 633 nla_put_failure: 634 return -ENOSPC; 635 } 636 637 static const struct nla_policy 638 sctp_timeout_nla_policy[CTA_TIMEOUT_SCTP_MAX+1] = { 639 [CTA_TIMEOUT_SCTP_CLOSED] = { .type = NLA_U32 }, 640 [CTA_TIMEOUT_SCTP_COOKIE_WAIT] = { .type = NLA_U32 }, 641 [CTA_TIMEOUT_SCTP_COOKIE_ECHOED] = { .type = NLA_U32 }, 642 [CTA_TIMEOUT_SCTP_ESTABLISHED] = { .type = NLA_U32 }, 643 [CTA_TIMEOUT_SCTP_SHUTDOWN_SENT] = { .type = NLA_U32 }, 644 [CTA_TIMEOUT_SCTP_SHUTDOWN_RECD] = { .type = NLA_U32 }, 645 [CTA_TIMEOUT_SCTP_SHUTDOWN_ACK_SENT] = { .type = NLA_U32 }, 646 [CTA_TIMEOUT_SCTP_HEARTBEAT_SENT] = { .type = NLA_U32 }, 647 [CTA_TIMEOUT_SCTP_HEARTBEAT_ACKED] = { .type = NLA_U32 }, 648 }; 649 #endif /* CONFIG_NF_CONNTRACK_TIMEOUT */ 650 651 652 #ifdef CONFIG_SYSCTL 653 static struct ctl_table sctp_sysctl_table[] = { 654 { 655 .procname = "nf_conntrack_sctp_timeout_closed", 656 .maxlen = sizeof(unsigned int), 657 .mode = 0644, 658 .proc_handler = proc_dointvec_jiffies, 659 }, 660 { 661 .procname = "nf_conntrack_sctp_timeout_cookie_wait", 662 .maxlen = sizeof(unsigned int), 663 .mode = 0644, 664 .proc_handler = proc_dointvec_jiffies, 665 }, 666 { 667 .procname = "nf_conntrack_sctp_timeout_cookie_echoed", 668 .maxlen = sizeof(unsigned int), 669 .mode = 0644, 670 .proc_handler = proc_dointvec_jiffies, 671 }, 672 { 673 .procname = "nf_conntrack_sctp_timeout_established", 674 .maxlen = sizeof(unsigned int), 675 .mode = 0644, 676 .proc_handler = proc_dointvec_jiffies, 677 }, 678 { 679 .procname = "nf_conntrack_sctp_timeout_shutdown_sent", 680 .maxlen = sizeof(unsigned int), 681 .mode = 0644, 682 .proc_handler = proc_dointvec_jiffies, 683 }, 684 { 685 .procname = "nf_conntrack_sctp_timeout_shutdown_recd", 686 .maxlen = sizeof(unsigned int), 687 .mode = 0644, 688 .proc_handler = proc_dointvec_jiffies, 689 }, 690 { 691 .procname = "nf_conntrack_sctp_timeout_shutdown_ack_sent", 692 .maxlen = sizeof(unsigned int), 693 .mode = 0644, 694 .proc_handler = proc_dointvec_jiffies, 695 }, 696 { 697 .procname = "nf_conntrack_sctp_timeout_heartbeat_sent", 698 .maxlen = sizeof(unsigned int), 699 .mode = 0644, 700 .proc_handler = proc_dointvec_jiffies, 701 }, 702 { 703 .procname = "nf_conntrack_sctp_timeout_heartbeat_acked", 704 .maxlen = sizeof(unsigned int), 705 .mode = 0644, 706 .proc_handler = proc_dointvec_jiffies, 707 }, 708 { } 709 }; 710 #endif 711 712 static int sctp_kmemdup_sysctl_table(struct nf_proto_net *pn, 713 struct nf_sctp_net *sn) 714 { 715 #ifdef CONFIG_SYSCTL 716 if (pn->ctl_table) 717 return 0; 718 719 pn->ctl_table = kmemdup(sctp_sysctl_table, 720 sizeof(sctp_sysctl_table), 721 GFP_KERNEL); 722 if (!pn->ctl_table) 723 return -ENOMEM; 724 725 pn->ctl_table[0].data = &sn->timeouts[SCTP_CONNTRACK_CLOSED]; 726 pn->ctl_table[1].data = &sn->timeouts[SCTP_CONNTRACK_COOKIE_WAIT]; 727 pn->ctl_table[2].data = &sn->timeouts[SCTP_CONNTRACK_COOKIE_ECHOED]; 728 pn->ctl_table[3].data = &sn->timeouts[SCTP_CONNTRACK_ESTABLISHED]; 729 pn->ctl_table[4].data = &sn->timeouts[SCTP_CONNTRACK_SHUTDOWN_SENT]; 730 pn->ctl_table[5].data = &sn->timeouts[SCTP_CONNTRACK_SHUTDOWN_RECD]; 731 pn->ctl_table[6].data = &sn->timeouts[SCTP_CONNTRACK_SHUTDOWN_ACK_SENT]; 732 pn->ctl_table[7].data = &sn->timeouts[SCTP_CONNTRACK_HEARTBEAT_SENT]; 733 pn->ctl_table[8].data = &sn->timeouts[SCTP_CONNTRACK_HEARTBEAT_ACKED]; 734 #endif 735 return 0; 736 } 737 738 static int sctp_init_net(struct net *net, u_int16_t proto) 739 { 740 struct nf_sctp_net *sn = sctp_pernet(net); 741 struct nf_proto_net *pn = &sn->pn; 742 743 if (!pn->users) { 744 int i; 745 746 for (i = 0; i < SCTP_CONNTRACK_MAX; i++) 747 sn->timeouts[i] = sctp_timeouts[i]; 748 749 /* timeouts[0] is unused, init it so ->timeouts[0] contains 750 * 'new' timeout, like udp or icmp. 751 */ 752 sn->timeouts[0] = sctp_timeouts[SCTP_CONNTRACK_CLOSED]; 753 } 754 755 return sctp_kmemdup_sysctl_table(pn, sn); 756 } 757 758 static struct nf_proto_net *sctp_get_net_proto(struct net *net) 759 { 760 return &net->ct.nf_ct_proto.sctp.pn; 761 } 762 763 const struct nf_conntrack_l4proto nf_conntrack_l4proto_sctp4 = { 764 .l3proto = PF_INET, 765 .l4proto = IPPROTO_SCTP, 766 #ifdef CONFIG_NF_CONNTRACK_PROCFS 767 .print_conntrack = sctp_print_conntrack, 768 #endif 769 .packet = sctp_packet, 770 .new = sctp_new, 771 .error = sctp_error, 772 .can_early_drop = sctp_can_early_drop, 773 .me = THIS_MODULE, 774 #if IS_ENABLED(CONFIG_NF_CT_NETLINK) 775 .nlattr_size = SCTP_NLATTR_SIZE, 776 .to_nlattr = sctp_to_nlattr, 777 .from_nlattr = nlattr_to_sctp, 778 .tuple_to_nlattr = nf_ct_port_tuple_to_nlattr, 779 .nlattr_tuple_size = nf_ct_port_nlattr_tuple_size, 780 .nlattr_to_tuple = nf_ct_port_nlattr_to_tuple, 781 .nla_policy = nf_ct_port_nla_policy, 782 #endif 783 #ifdef CONFIG_NF_CONNTRACK_TIMEOUT 784 .ctnl_timeout = { 785 .nlattr_to_obj = sctp_timeout_nlattr_to_obj, 786 .obj_to_nlattr = sctp_timeout_obj_to_nlattr, 787 .nlattr_max = CTA_TIMEOUT_SCTP_MAX, 788 .obj_size = sizeof(unsigned int) * SCTP_CONNTRACK_MAX, 789 .nla_policy = sctp_timeout_nla_policy, 790 }, 791 #endif /* CONFIG_NF_CONNTRACK_TIMEOUT */ 792 .init_net = sctp_init_net, 793 .get_net_proto = sctp_get_net_proto, 794 }; 795 EXPORT_SYMBOL_GPL(nf_conntrack_l4proto_sctp4); 796 797 const struct nf_conntrack_l4proto nf_conntrack_l4proto_sctp6 = { 798 .l3proto = PF_INET6, 799 .l4proto = IPPROTO_SCTP, 800 #ifdef CONFIG_NF_CONNTRACK_PROCFS 801 .print_conntrack = sctp_print_conntrack, 802 #endif 803 .packet = sctp_packet, 804 .new = sctp_new, 805 .error = sctp_error, 806 .can_early_drop = sctp_can_early_drop, 807 .me = THIS_MODULE, 808 #if IS_ENABLED(CONFIG_NF_CT_NETLINK) 809 .nlattr_size = SCTP_NLATTR_SIZE, 810 .to_nlattr = sctp_to_nlattr, 811 .from_nlattr = nlattr_to_sctp, 812 .tuple_to_nlattr = nf_ct_port_tuple_to_nlattr, 813 .nlattr_tuple_size = nf_ct_port_nlattr_tuple_size, 814 .nlattr_to_tuple = nf_ct_port_nlattr_to_tuple, 815 .nla_policy = nf_ct_port_nla_policy, 816 #endif 817 #ifdef CONFIG_NF_CONNTRACK_TIMEOUT 818 .ctnl_timeout = { 819 .nlattr_to_obj = sctp_timeout_nlattr_to_obj, 820 .obj_to_nlattr = sctp_timeout_obj_to_nlattr, 821 .nlattr_max = CTA_TIMEOUT_SCTP_MAX, 822 .obj_size = sizeof(unsigned int) * SCTP_CONNTRACK_MAX, 823 .nla_policy = sctp_timeout_nla_policy, 824 }, 825 #endif /* CONFIG_NF_CONNTRACK_TIMEOUT */ 826 .init_net = sctp_init_net, 827 .get_net_proto = sctp_get_net_proto, 828 }; 829 EXPORT_SYMBOL_GPL(nf_conntrack_l4proto_sctp6); 830