1 /* 2 * CDDL HEADER START 3 * 4 * The contents of this file are subject to the terms of the 5 * Common Development and Distribution License (the "License"). 6 * You may not use this file except in compliance with the License. 7 * 8 * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE 9 * or http://www.opensolaris.org/os/licensing. 10 * See the License for the specific language governing permissions 11 * and limitations under the License. 12 * 13 * When distributing Covered Code, include this CDDL HEADER in each 14 * file and include the License file at usr/src/OPENSOLARIS.LICENSE. 15 * If applicable, add the following below this CDDL HEADER, with the 16 * fields enclosed by brackets "[]" replaced with your own identifying 17 * information: Portions Copyright [yyyy] [name of copyright owner] 18 * 19 * CDDL HEADER END 20 */ 21 22 /* 23 * Copyright 2009 Sun Microsystems, Inc. All rights reserved. 24 * Use is subject to license terms. 25 */ 26 27 #include <sys/types.h> 28 #include <sys/systm.h> 29 #include <sys/stream.h> 30 #include <sys/cmn_err.h> 31 #include <sys/ddi.h> 32 #include <sys/strsubr.h> 33 #include <sys/tsol/tnet.h> 34 35 #include <netinet/in.h> 36 #include <netinet/ip6.h> 37 38 #include <inet/common.h> 39 #include <inet/ip.h> 40 #include <inet/ip6.h> 41 #include <inet/mib2.h> 42 #include <inet/sctp_ip.h> 43 #include <inet/ipclassifier.h> 44 #include <inet/ip_ire.h> 45 #include "sctp_impl.h" 46 #include "sctp_asconf.h" 47 48 ssize_t 49 sctp_link_abort(mblk_t *mp, uint16_t serror, char *details, size_t len, 50 int iserror, boolean_t tbit) 51 { 52 size_t alen; 53 mblk_t *amp; 54 sctp_chunk_hdr_t *acp; 55 sctp_parm_hdr_t *eph; 56 57 ASSERT(mp != NULL && mp->b_cont == NULL); 58 59 alen = sizeof (*acp) + (serror != 0 ? (sizeof (*eph) + len) : 0); 60 61 amp = allocb(alen, BPRI_MED); 62 if (amp == NULL) { 63 return (-1); 64 } 65 66 amp->b_wptr = amp->b_rptr + alen; 67 68 /* Chunk header */ 69 acp = (sctp_chunk_hdr_t *)amp->b_rptr; 70 acp->sch_id = iserror ? CHUNK_ERROR : CHUNK_ABORT; 71 acp->sch_flags = 0; 72 acp->sch_len = htons(alen); 73 if (tbit) 74 SCTP_SET_TBIT(acp); 75 76 linkb(mp, amp); 77 78 if (serror == 0) { 79 return (alen); 80 } 81 82 eph = (sctp_parm_hdr_t *)(acp + 1); 83 eph->sph_type = htons(serror); 84 eph->sph_len = htons(len + sizeof (*eph)); 85 86 if (len > 0) { 87 bcopy(details, eph + 1, len); 88 } 89 90 /* XXX pad */ 91 92 return (alen); 93 } 94 95 void 96 sctp_user_abort(sctp_t *sctp, mblk_t *data) 97 { 98 mblk_t *mp; 99 int len, hdrlen; 100 char *cause; 101 sctp_faddr_t *fp = sctp->sctp_current; 102 sctp_stack_t *sctps = sctp->sctp_sctps; 103 104 /* 105 * Don't need notification if connection is not yet setup, 106 * call sctp_clean_death() to reclaim resources. 107 * Any pending connect call(s) will error out. 108 */ 109 if (sctp->sctp_state < SCTPS_COOKIE_WAIT) { 110 sctp_clean_death(sctp, ECONNABORTED); 111 return; 112 } 113 114 mp = sctp_make_mp(sctp, fp, 0); 115 if (mp == NULL) { 116 SCTP_KSTAT(sctps, sctp_send_user_abort_failed); 117 return; 118 } 119 120 /* 121 * Create abort chunk. 122 */ 123 if (data) { 124 if (fp->isv4) { 125 hdrlen = sctp->sctp_hdr_len; 126 } else { 127 hdrlen = sctp->sctp_hdr6_len; 128 } 129 hdrlen += sizeof (sctp_chunk_hdr_t) + sizeof (sctp_parm_hdr_t); 130 cause = (char *)data->b_rptr; 131 len = data->b_wptr - data->b_rptr; 132 133 if (len + hdrlen > fp->sfa_pmss) { 134 len = fp->sfa_pmss - hdrlen; 135 } 136 } else { 137 cause = NULL; 138 len = 0; 139 } 140 /* 141 * Since it is a user abort, we should have the sctp_t and hence 142 * the correct verification tag. So we should not set the T-bit 143 * in the ABORT. 144 */ 145 if ((len = sctp_link_abort(mp, SCTP_ERR_USER_ABORT, cause, len, 0, 146 B_FALSE)) < 0) { 147 freemsg(mp); 148 return; 149 } 150 sctp_set_iplen(sctp, mp); 151 BUMP_MIB(&sctps->sctps_mib, sctpAborted); 152 BUMP_LOCAL(sctp->sctp_opkts); 153 BUMP_LOCAL(sctp->sctp_obchunks); 154 155 CONN_INC_REF(sctp->sctp_connp); 156 mp->b_flag |= MSGHASREF; 157 IP_PUT(mp, sctp->sctp_connp, fp->isv4); 158 159 sctp_assoc_event(sctp, SCTP_COMM_LOST, 0, NULL); 160 sctp_clean_death(sctp, ECONNABORTED); 161 } 162 163 /* 164 * If iserror == 0, sends an abort. If iserror != 0, sends an error. 165 */ 166 void 167 sctp_send_abort(sctp_t *sctp, uint32_t vtag, uint16_t serror, char *details, 168 size_t len, mblk_t *inmp, int iserror, boolean_t tbit) 169 { 170 171 mblk_t *hmp; 172 uint32_t ip_hdr_len; 173 ipha_t *iniph; 174 ipha_t *ahiph; 175 ip6_t *inip6h; 176 ip6_t *ahip6h; 177 sctp_hdr_t *sh; 178 sctp_hdr_t *insh; 179 size_t ahlen; 180 uchar_t *p; 181 ssize_t alen; 182 int isv4; 183 ire_t *ire; 184 irb_t *irb; 185 ts_label_t *tsl; 186 conn_t *connp; 187 cred_t *cr = NULL; 188 sctp_stack_t *sctps = sctp->sctp_sctps; 189 ip_stack_t *ipst; 190 191 isv4 = (IPH_HDR_VERSION(inmp->b_rptr) == IPV4_VERSION); 192 if (isv4) { 193 ahlen = sctp->sctp_hdr_len; 194 } else { 195 ahlen = sctp->sctp_hdr6_len; 196 } 197 198 /* 199 * If this is a labeled system, then check to see if we're allowed to 200 * send a response to this particular sender. If not, then just drop. 201 */ 202 if (is_system_labeled() && !tsol_can_reply_error(inmp)) 203 return; 204 205 hmp = allocb_cred(sctps->sctps_wroff_xtra + ahlen, 206 CONN_CRED(sctp->sctp_connp), sctp->sctp_cpid); 207 if (hmp == NULL) { 208 /* XXX no resources */ 209 return; 210 } 211 212 /* copy in the IP / SCTP header */ 213 p = hmp->b_rptr + sctps->sctps_wroff_xtra; 214 hmp->b_rptr = p; 215 hmp->b_wptr = p + ahlen; 216 if (isv4) { 217 bcopy(sctp->sctp_iphc, p, sctp->sctp_hdr_len); 218 /* 219 * Composite is likely incomplete at this point, so pull 220 * info from the incoming IP / SCTP headers. 221 */ 222 ahiph = (ipha_t *)p; 223 iniph = (ipha_t *)inmp->b_rptr; 224 ip_hdr_len = IPH_HDR_LENGTH(inmp->b_rptr); 225 226 sh = (sctp_hdr_t *)(p + sctp->sctp_ip_hdr_len); 227 ASSERT(OK_32PTR(sh)); 228 229 insh = (sctp_hdr_t *)((uchar_t *)iniph + ip_hdr_len); 230 ASSERT(OK_32PTR(insh)); 231 232 /* Copy in the peer's IP addr */ 233 ahiph->ipha_dst = iniph->ipha_src; 234 ahiph->ipha_src = iniph->ipha_dst; 235 } else { 236 bcopy(sctp->sctp_iphc6, p, sctp->sctp_hdr6_len); 237 ahip6h = (ip6_t *)p; 238 inip6h = (ip6_t *)inmp->b_rptr; 239 ip_hdr_len = ip_hdr_length_v6(inmp, inip6h); 240 241 sh = (sctp_hdr_t *)(p + sctp->sctp_ip_hdr6_len); 242 ASSERT(OK_32PTR(sh)); 243 244 insh = (sctp_hdr_t *)((uchar_t *)inip6h + ip_hdr_len); 245 ASSERT(OK_32PTR(insh)); 246 247 /* Copy in the peer's IP addr */ 248 ahip6h->ip6_dst = inip6h->ip6_src; 249 ahip6h->ip6_src = inip6h->ip6_dst; 250 } 251 252 /* Fill in the holes in the SCTP common header */ 253 sh->sh_sport = insh->sh_dport; 254 sh->sh_dport = insh->sh_sport; 255 sh->sh_verf = vtag; 256 257 /* Link in the abort chunk */ 258 if ((alen = sctp_link_abort(hmp, serror, details, len, iserror, tbit)) 259 < 0) { 260 freemsg(hmp); 261 return; 262 } 263 264 if (isv4) { 265 ahiph->ipha_length = htons(ahlen + alen); 266 } else { 267 ahip6h->ip6_plen = htons(alen + sizeof (*sh)); 268 } 269 270 BUMP_MIB(&sctps->sctps_mib, sctpAborted); 271 BUMP_LOCAL(sctp->sctp_obchunks); 272 273 ipst = sctps->sctps_netstack->netstack_ip; 274 connp = sctp->sctp_connp; 275 if (is_system_labeled() && (cr = msg_getcred(inmp, NULL)) != NULL && 276 crgetlabel(cr) != NULL) { 277 int err; 278 boolean_t exempt = connp->conn_mac_exempt; 279 280 if (isv4) 281 err = tsol_check_label(cr, &hmp, exempt, ipst); 282 else 283 err = tsol_check_label_v6(cr, &hmp, exempt, ipst); 284 if (err != 0) { 285 freemsg(hmp); 286 return; 287 } 288 } 289 290 /* Stash the conn ptr info. for IP */ 291 SCTP_STASH_IPINFO(hmp, NULL); 292 293 CONN_INC_REF(connp); 294 hmp->b_flag |= MSGHASREF; 295 IP_PUT(hmp, connp, sctp->sctp_current == NULL ? B_TRUE : 296 sctp->sctp_current->isv4); 297 /* 298 * Let's just mark the IRE for this destination as temporary 299 * to prevent any DoS attack. 300 */ 301 tsl = cr == NULL ? NULL : crgetlabel(cr); 302 if (isv4) { 303 ire = ire_cache_lookup(iniph->ipha_src, sctp->sctp_zoneid, tsl, 304 ipst); 305 } else { 306 ire = ire_cache_lookup_v6(&inip6h->ip6_src, sctp->sctp_zoneid, 307 tsl, ipst); 308 } 309 /* 310 * In the normal case the ire would be non-null, however it could be 311 * null, say, if IP needs to resolve the gateway for this address. We 312 * only care about IRE_CACHE. 313 */ 314 if (ire == NULL) 315 return; 316 if (ire->ire_type != IRE_CACHE) { 317 ire_refrele(ire); 318 return; 319 } 320 irb = ire->ire_bucket; 321 /* ire_lock is not needed, as ire_marks is protected by irb_lock */ 322 rw_enter(&irb->irb_lock, RW_WRITER); 323 /* 324 * Only increment the temporary IRE count if the original 325 * IRE is not already marked temporary. 326 */ 327 if (!(ire->ire_marks & IRE_MARK_TEMPORARY)) { 328 irb->irb_tmp_ire_cnt++; 329 ire->ire_marks |= IRE_MARK_TEMPORARY; 330 } 331 rw_exit(&irb->irb_lock); 332 ire_refrele(ire); 333 } 334 335 /*ARGSUSED*/ 336 mblk_t * 337 sctp_make_err(sctp_t *sctp, uint16_t serror, void *details, size_t len) 338 { 339 340 mblk_t *emp; 341 size_t elen; 342 sctp_chunk_hdr_t *ecp; 343 sctp_parm_hdr_t *eph; 344 int pad; 345 346 if ((pad = len % SCTP_ALIGN) != 0) { 347 pad = SCTP_ALIGN - pad; 348 } 349 350 elen = sizeof (*ecp) + sizeof (*eph) + len; 351 emp = allocb(elen + pad, BPRI_MED); 352 if (emp == NULL) { 353 return (NULL); 354 } 355 356 emp->b_wptr = emp->b_rptr + elen + pad; 357 358 /* Chunk header */ 359 ecp = (sctp_chunk_hdr_t *)emp->b_rptr; 360 ecp->sch_id = CHUNK_ERROR; 361 ecp->sch_flags = 0; 362 ecp->sch_len = htons(elen); 363 364 eph = (sctp_parm_hdr_t *)(ecp + 1); 365 eph->sph_type = htons(serror); 366 eph->sph_len = htons(len + sizeof (*eph)); 367 368 if (len > 0) { 369 bcopy(details, eph + 1, len); 370 } 371 372 if (pad != 0) { 373 bzero((uchar_t *)(eph + 1) + len, pad); 374 } 375 376 return (emp); 377 } 378 379 /* 380 * Called from sctp_input_data() to add one error chunk to the error 381 * chunks list. The error chunks list will be processed at the end 382 * of sctp_input_data() by calling sctp_process_err(). 383 */ 384 void 385 sctp_add_err(sctp_t *sctp, uint16_t serror, void *details, size_t len, 386 sctp_faddr_t *dest) 387 { 388 sctp_stack_t *sctps = sctp->sctp_sctps; 389 mblk_t *emp; 390 uint32_t emp_len; 391 uint32_t mss; 392 mblk_t *sendmp; 393 sctp_faddr_t *fp; 394 395 emp = sctp_make_err(sctp, serror, details, len); 396 if (emp == NULL) 397 return; 398 emp_len = MBLKL(emp); 399 if (sctp->sctp_err_chunks != NULL) { 400 fp = SCTP_CHUNK_DEST(sctp->sctp_err_chunks); 401 } else { 402 fp = dest; 403 SCTP_SET_CHUNK_DEST(emp, dest); 404 } 405 mss = fp->sfa_pmss; 406 407 /* 408 * If the current output packet cannot include the new error chunk, 409 * send out the current packet and then add the new error chunk 410 * to the new output packet. 411 */ 412 if (sctp->sctp_err_len + emp_len > mss) { 413 if ((sendmp = sctp_make_mp(sctp, fp, 0)) == NULL) { 414 SCTP_KSTAT(sctps, sctp_send_err_failed); 415 /* Just free the latest error chunk. */ 416 freeb(emp); 417 return; 418 } 419 sendmp->b_cont = sctp->sctp_err_chunks; 420 sctp_set_iplen(sctp, sendmp); 421 sctp_add_sendq(sctp, sendmp); 422 423 sctp->sctp_err_chunks = emp; 424 sctp->sctp_err_len = emp_len; 425 SCTP_SET_CHUNK_DEST(emp, dest); 426 } else { 427 if (sctp->sctp_err_chunks != NULL) 428 linkb(sctp->sctp_err_chunks, emp); 429 else 430 sctp->sctp_err_chunks = emp; 431 sctp->sctp_err_len += emp_len; 432 } 433 /* Assume that we will send it out... */ 434 BUMP_LOCAL(sctp->sctp_obchunks); 435 } 436 437 /* 438 * Called from sctp_input_data() to send out error chunks created during 439 * the processing of all the chunks in an incoming packet. 440 */ 441 void 442 sctp_process_err(sctp_t *sctp) 443 { 444 sctp_stack_t *sctps = sctp->sctp_sctps; 445 mblk_t *errmp; 446 mblk_t *sendmp; 447 448 ASSERT(sctp->sctp_err_chunks != NULL); 449 errmp = sctp->sctp_err_chunks; 450 if ((sendmp = sctp_make_mp(sctp, SCTP_CHUNK_DEST(errmp), 0)) == NULL) { 451 SCTP_KSTAT(sctps, sctp_send_err_failed); 452 freemsg(errmp); 453 goto done; 454 } 455 sendmp->b_cont = errmp; 456 sctp_set_iplen(sctp, sendmp); 457 sctp_add_sendq(sctp, sendmp); 458 done: 459 sctp->sctp_err_chunks = NULL; 460 sctp->sctp_err_len = 0; 461 } 462 463 /* 464 * Returns 0 on non-fatal error, otherwise a system error on fatal 465 * error. 466 */ 467 int 468 sctp_handle_error(sctp_t *sctp, sctp_hdr_t *sctph, sctp_chunk_hdr_t *ch, 469 mblk_t *mp) 470 { 471 sctp_parm_hdr_t *errh; 472 sctp_chunk_hdr_t *uch; 473 474 if (ch->sch_len == htons(sizeof (*ch))) { 475 /* no error cause given */ 476 return (0); 477 } 478 errh = (sctp_parm_hdr_t *)(ch + 1); 479 sctp_error_event(sctp, ch); 480 481 switch (errh->sph_type) { 482 /* 483 * Both BAD_SID and NO_USR_DATA errors 484 * indicate a serious bug in our stack, 485 * so complain and abort the association. 486 */ 487 case SCTP_ERR_BAD_SID: 488 cmn_err(CE_WARN, "BUG! send to invalid SID"); 489 sctp_send_abort(sctp, sctph->sh_verf, 0, NULL, 0, mp, 0, 0); 490 return (ECONNABORTED); 491 case SCTP_ERR_NO_USR_DATA: 492 cmn_err(CE_WARN, "BUG! no usr data"); 493 sctp_send_abort(sctp, sctph->sh_verf, 0, NULL, 0, mp, 0, 0); 494 return (ECONNABORTED); 495 case SCTP_ERR_UNREC_CHUNK: 496 /* Pull out the unrecognized chunk type */ 497 if (ntohs(errh->sph_len) < (sizeof (*errh) + sizeof (*uch))) { 498 /* Not enough to process */ 499 return (0); 500 } 501 uch = (sctp_chunk_hdr_t *)(errh + 1); 502 if (uch->sch_id == CHUNK_ASCONF) { 503 /* Turn on ASCONF sending */ 504 sctp->sctp_understands_asconf = B_FALSE; 505 /* 506 * Hand off to asconf to clear out the unacked 507 * asconf chunk. 508 */ 509 if (ntohs(uch->sch_len) != 510 (ntohs(errh->sph_len) - sizeof (*errh))) { 511 /* malformed */ 512 dprint(0, ("Malformed Unrec Chunk error\n")); 513 return (0); 514 } 515 sctp_asconf_free_cxmit(sctp, uch); 516 return (0); 517 } 518 /* Else drop it */ 519 break; 520 default: 521 break; 522 } 523 524 return (0); 525 } 526