1/* $KAME: rtsol.c,v 1.27 2003/10/05 00:09:36 itojun Exp $ */ 2 3/*- 4 * SPDX-License-Identifier: BSD-3-Clause 5 * 6 * Copyright (C) 1995, 1996, 1997, and 1998 WIDE Project. 7 * Copyright (C) 2011 Hiroki Sato 8 * All rights reserved. 9 * 10 * Redistribution and use in source and binary forms, with or without 11 * modification, are permitted provided that the following conditions 12 * are met: 13 * 1. Redistributions of source code must retain the above copyright 14 * notice, this list of conditions and the following disclaimer. 15 * 2. Redistributions in binary form must reproduce the above copyright 16 * notice, this list of conditions and the following disclaimer in the 17 * documentation and/or other materials provided with the distribution. 18 * 3. Neither the name of the project nor the names of its contributors 19 * may be used to endorse or promote products derived from this software 20 * without specific prior written permission. 21 * 22 * THIS SOFTWARE IS PROVIDED BY THE PROJECT AND CONTRIBUTORS ``AS IS'' AND 23 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 24 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 25 * ARE DISCLAIMED. IN NO EVENT SHALL THE PROJECT OR CONTRIBUTORS BE LIABLE 26 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 27 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 28 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 29 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 30 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 31 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 32 * SUCH DAMAGE. 33 */ 34 35#include <sys/param.h> 36#include <sys/capsicum.h> 37#include <sys/queue.h> 38#include <sys/socket.h> 39#include <sys/stat.h> 40#include <sys/uio.h> 41#include <sys/wait.h> 42 43#include <net/if.h> 44#include <net/route.h> 45#include <net/if_dl.h> 46 47#define __BSD_VISIBLE 1 /* IN6ADDR_LINKLOCAL_ALLROUTERS_INIT */ 48#include <netinet/in.h> 49#undef __BSD_VISIBLE 50#include <netinet/ip6.h> 51#include <netinet6/ip6_var.h> 52#include <netinet/icmp6.h> 53 54#include <arpa/inet.h> 55 56#include <capsicum_helpers.h> 57#include <netdb.h> 58#include <time.h> 59#include <fcntl.h> 60#include <unistd.h> 61#include <stdio.h> 62#include <time.h> 63#include <err.h> 64#include <errno.h> 65#include <string.h> 66#include <stdlib.h> 67#include <syslog.h> 68#include "rtsold.h" 69 70static char rsid[IFNAMSIZ + 1 + sizeof(DNSINFO_ORIGIN_LABEL) + 1 + NI_MAXHOST]; 71struct ifinfo_head_t ifinfo_head = TAILQ_HEAD_INITIALIZER(ifinfo_head); 72 73static void call_script(const char *const *, struct script_msg_head_t *); 74static size_t dname_labeldec(char *, size_t, const char *); 75static struct ra_opt *find_raopt(struct rainfo *, int, void *, size_t); 76static int ra_opt_rdnss_dispatch(struct ifinfo *, struct rainfo *, 77 struct script_msg_head_t *, struct script_msg_head_t *); 78static char *make_rsid(const char *, const char *, struct rainfo *); 79 80#define _ARGS_MANAGED managedconf_script, ifi->ifname, rasender 81#define _ARGS_OTHER otherconf_script, ifi->ifname, rasender 82#define _ARGS_ALWAYS alwaysconf_script, ifi->ifname, rasender 83#define _ARGS_RESADD resolvconf_script, "-a", rsid 84#define _ARGS_RESDEL resolvconf_script, "-d", rsid 85 86#define CALL_SCRIPT(name, sm_head) do { \ 87 const char *const sarg[] = { _ARGS_##name, NULL }; \ 88 call_script(sarg, sm_head); \ 89} while (0) 90 91#define ELM_MALLOC(p, error_action) do { \ 92 p = malloc(sizeof(*p)); \ 93 if (p == NULL) { \ 94 warnmsg(LOG_ERR, __func__, "malloc failed: %s", \ 95 strerror(errno)); \ 96 error_action; \ 97 } \ 98 memset(p, 0, sizeof(*p)); \ 99} while (0) 100 101int 102recvsockopen(void) 103{ 104 struct icmp6_filter filt; 105 cap_rights_t rights; 106 int on, sock; 107 108 if ((sock = socket(AF_INET6, SOCK_RAW, IPPROTO_ICMPV6)) < 0) { 109 warnmsg(LOG_ERR, __func__, "socket: %s", strerror(errno)); 110 goto fail; 111 } 112 113 /* Provide info about the receiving interface. */ 114 on = 1; 115 if (setsockopt(sock, IPPROTO_IPV6, IPV6_RECVPKTINFO, &on, 116 sizeof(on)) < 0) { 117 warnmsg(LOG_ERR, __func__, "setsockopt(IPV6_RECVPKTINFO): %s", 118 strerror(errno)); 119 goto fail; 120 } 121 122 /* Include the hop limit from the received header. */ 123 on = 1; 124 if (setsockopt(sock, IPPROTO_IPV6, IPV6_RECVHOPLIMIT, &on, 125 sizeof(on)) < 0) { 126 warnmsg(LOG_ERR, __func__, "setsockopt(IPV6_RECVHOPLIMIT): %s", 127 strerror(errno)); 128 goto fail; 129 } 130 131 /* Filter out everything except for Router Advertisements. */ 132 ICMP6_FILTER_SETBLOCKALL(&filt); 133 ICMP6_FILTER_SETPASS(ND_ROUTER_ADVERT, &filt); 134 if (setsockopt(sock, IPPROTO_ICMPV6, ICMP6_FILTER, &filt, 135 sizeof(filt)) == -1) { 136 warnmsg(LOG_ERR, __func__, "setsockopt(ICMP6_FILTER): %s", 137 strerror(errno)); 138 goto fail; 139 } 140 141 cap_rights_init(&rights, CAP_EVENT, CAP_RECV); 142 if (caph_rights_limit(sock, &rights) < 0) { 143 warnmsg(LOG_ERR, __func__, "caph_rights_limit(): %s", 144 strerror(errno)); 145 goto fail; 146 } 147 148 return (sock); 149 150fail: 151 if (sock >= 0) 152 (void)close(sock); 153 return (-1); 154} 155 156void 157rtsol_input(int sock) 158{ 159 uint8_t cmsg[CMSG_SPACE(sizeof(struct in6_pktinfo)) + 160 CMSG_SPACE(sizeof(int))]; 161 struct iovec iov; 162 struct msghdr hdr; 163 struct sockaddr_in6 from; 164 char answer[1500], ntopbuf[INET6_ADDRSTRLEN], ifnamebuf[IFNAMSIZ]; 165 int l, ifindex = 0, *hlimp = NULL; 166 ssize_t msglen; 167 struct in6_pktinfo *pi = NULL; 168 struct ifinfo *ifi = NULL; 169 struct ra_opt *rao = NULL; 170 struct icmp6_hdr *icp; 171 struct nd_router_advert *nd_ra; 172 struct cmsghdr *cm; 173 struct rainfo *rai; 174 char *p, *raoptp; 175 struct in6_addr *addr; 176 struct nd_opt_hdr *ndo; 177 struct nd_opt_rdnss *rdnss; 178 struct nd_opt_dnssl *dnssl; 179 size_t len; 180 char nsbuf[INET6_ADDRSTRLEN + 1 + IFNAMSIZ + 1]; 181 char dname[NI_MAXHOST]; 182 struct timespec lifetime, now; 183 int newent_rai, newent_rao; 184 185 memset(&hdr, 0, sizeof(hdr)); 186 hdr.msg_iov = &iov; 187 hdr.msg_iovlen = 1; 188 hdr.msg_name = &from; 189 hdr.msg_namelen = sizeof(from); 190 hdr.msg_control = cmsg; 191 hdr.msg_controllen = sizeof(cmsg); 192 193 iov.iov_base = (caddr_t)answer; 194 iov.iov_len = sizeof(answer); 195 196 if ((msglen = recvmsg(sock, &hdr, 0)) < 0) { 197 warnmsg(LOG_ERR, __func__, "recvmsg: %s", strerror(errno)); 198 return; 199 } 200 201 /* Extract control message info. */ 202 for (cm = (struct cmsghdr *)CMSG_FIRSTHDR(&hdr); cm != NULL; 203 cm = (struct cmsghdr *)CMSG_NXTHDR(&hdr, cm)) { 204 if (cm->cmsg_level == IPPROTO_IPV6 && 205 cm->cmsg_type == IPV6_PKTINFO && 206 cm->cmsg_len == CMSG_LEN(sizeof(struct in6_pktinfo))) { 207 pi = (struct in6_pktinfo *)(void *)(CMSG_DATA(cm)); 208 ifindex = pi->ipi6_ifindex; 209 } 210 if (cm->cmsg_level == IPPROTO_IPV6 && 211 cm->cmsg_type == IPV6_HOPLIMIT && 212 cm->cmsg_len == CMSG_LEN(sizeof(int))) 213 hlimp = (int *)(void *)CMSG_DATA(cm); 214 } 215 216 if (ifindex == 0) { 217 warnmsg(LOG_ERR, __func__, 218 "failed to get receiving interface"); 219 return; 220 } 221 if (hlimp == NULL) { 222 warnmsg(LOG_ERR, __func__, 223 "failed to get receiving hop limit"); 224 return; 225 } 226 227 if ((size_t)msglen < sizeof(struct nd_router_advert)) { 228 warnmsg(LOG_INFO, __func__, 229 "packet size(%zd) is too short", msglen); 230 return; 231 } 232 233 icp = (struct icmp6_hdr *)iov.iov_base; 234 if (icp->icmp6_type != ND_ROUTER_ADVERT) { 235 /* 236 * this should not happen because we configured a filter 237 * that only passes RAs on the receiving socket. 238 */ 239 warnmsg(LOG_ERR, __func__, 240 "invalid icmp type(%d) from %s on %s", icp->icmp6_type, 241 inet_ntop(AF_INET6, &from.sin6_addr, ntopbuf, 242 sizeof(ntopbuf)), 243 if_indextoname(pi->ipi6_ifindex, ifnamebuf)); 244 return; 245 } 246 247 if (icp->icmp6_code != 0) { 248 warnmsg(LOG_INFO, __func__, 249 "invalid icmp code(%d) from %s on %s", icp->icmp6_code, 250 inet_ntop(AF_INET6, &from.sin6_addr, ntopbuf, 251 sizeof(ntopbuf)), 252 if_indextoname(pi->ipi6_ifindex, ifnamebuf)); 253 return; 254 } 255 256 if (*hlimp != 255) { 257 warnmsg(LOG_INFO, __func__, 258 "invalid RA with hop limit(%d) from %s on %s", 259 *hlimp, 260 inet_ntop(AF_INET6, &from.sin6_addr, ntopbuf, 261 sizeof(ntopbuf)), 262 if_indextoname(pi->ipi6_ifindex, ifnamebuf)); 263 return; 264 } 265 266 if (pi && !IN6_IS_ADDR_LINKLOCAL(&from.sin6_addr)) { 267 warnmsg(LOG_INFO, __func__, 268 "invalid RA with non link-local source from %s on %s", 269 inet_ntop(AF_INET6, &from.sin6_addr, ntopbuf, 270 sizeof(ntopbuf)), 271 if_indextoname(pi->ipi6_ifindex, ifnamebuf)); 272 return; 273 } 274 275 /* xxx: more validation? */ 276 277 if ((ifi = find_ifinfo(pi->ipi6_ifindex)) == NULL) { 278 warnmsg(LOG_DEBUG, __func__, 279 "received RA from %s on an unexpected IF(%s)", 280 inet_ntop(AF_INET6, &from.sin6_addr, ntopbuf, 281 sizeof(ntopbuf)), 282 if_indextoname(pi->ipi6_ifindex, ifnamebuf)); 283 return; 284 } 285 286 warnmsg(LOG_DEBUG, __func__, 287 "received RA from %s on %s, state is %d", 288 inet_ntop(AF_INET6, &from.sin6_addr, ntopbuf, sizeof(ntopbuf)), 289 ifi->ifname, ifi->state); 290 291 nd_ra = (struct nd_router_advert *)icp; 292 293 /* 294 * Process the "M bit." 295 * If the value of ManagedConfigFlag changes from FALSE to TRUE, the 296 * host should invoke the stateful autoconfiguration protocol, 297 * requesting information. 298 * [RFC 4861 Section 4.2] 299 * XXX ??? [draft-ietf-v6ops-dhcpv6-slaac-problem-07] 300 */ 301 if (((nd_ra->nd_ra_flags_reserved) & ND_RA_FLAG_MANAGED) && 302 !ifi->managedconfig) { 303 const char *rasender = inet_ntop(AF_INET6, &from.sin6_addr, 304 ntopbuf, sizeof(ntopbuf)); 305 warnmsg(LOG_DEBUG, __func__, 306 "ManagedConfigFlag on %s is turned on", ifi->ifname); 307 ifi->managedconfig = 1; 308 CALL_SCRIPT(MANAGED, NULL); 309 } 310 311 /* 312 * Process the "O bit." 313 * If the value of OtherConfigFlag changes from FALSE to TRUE, the 314 * host should invoke the stateful autoconfiguration protocol, 315 * requesting information unless the "M bit" was set as well in 316 * which case the "O bit" is redundant. 317 * [RFC 4861 Section 4.2] 318 */ 319 if (((nd_ra->nd_ra_flags_reserved) & ND_RA_FLAG_OTHER) && 320 !ifi->otherconfig) { 321 const char *rasender = inet_ntop(AF_INET6, &from.sin6_addr, 322 ntopbuf, sizeof(ntopbuf)); 323 warnmsg(LOG_DEBUG, __func__, 324 "OtherConfigFlag on %s is turned on", ifi->ifname); 325 ifi->otherconfig = 1; 326 if (!ifi->managedconfig) 327 CALL_SCRIPT(OTHER, NULL); 328 } 329 330 /* 331 * "Always" script. 332 */ 333 if (!ifi->alwaysconfig) { 334 const char *rasender = inet_ntop(AF_INET6, &from.sin6_addr, 335 ntopbuf, sizeof(ntopbuf)); 336 ifi->alwaysconfig = 1; 337 CALL_SCRIPT(ALWAYS, NULL); 338 } 339 340 clock_gettime(CLOCK_MONOTONIC_FAST, &now); 341 newent_rai = 0; 342 rai = find_rainfo(ifi, &from); 343 if (rai == NULL) { 344 ELM_MALLOC(rai, exit(1)); 345 rai->rai_ifinfo = ifi; 346 TAILQ_INIT(&rai->rai_ra_opt); 347 rai->rai_saddr.sin6_family = AF_INET6; 348 rai->rai_saddr.sin6_len = sizeof(rai->rai_saddr); 349 memcpy(&rai->rai_saddr.sin6_addr, &from.sin6_addr, 350 sizeof(rai->rai_saddr.sin6_addr)); 351 newent_rai = 1; 352 } 353 354#define RA_OPT_NEXT_HDR(x) (struct nd_opt_hdr *)((char *)(x) + \ 355 (((struct nd_opt_hdr *)(x))->nd_opt_len * 8)) 356 /* Process RA options. */ 357 warnmsg(LOG_DEBUG, __func__, "Processing RA"); 358 raoptp = (char *)icp + sizeof(struct nd_router_advert); 359 while (raoptp < (char *)icp + msglen) { 360 ndo = (struct nd_opt_hdr *)raoptp; 361 warnmsg(LOG_DEBUG, __func__, "ndo = %p", raoptp); 362 warnmsg(LOG_DEBUG, __func__, "ndo->nd_opt_type = %d", 363 ndo->nd_opt_type); 364 warnmsg(LOG_DEBUG, __func__, "ndo->nd_opt_len = %d", 365 ndo->nd_opt_len); 366 367 if (ndo->nd_opt_len == 0) { 368 warnmsg(LOG_INFO, __func__, "invalid option length 0."); 369 break; 370 } 371 if ((char *)RA_OPT_NEXT_HDR(raoptp) > (char *)icp + msglen) { 372 warnmsg(LOG_INFO, __func__, "option length overflow."); 373 break; 374 } 375 376 switch (ndo->nd_opt_type) { 377 case ND_OPT_RDNSS: 378 rdnss = (struct nd_opt_rdnss *)raoptp; 379 380 /* 381 * The option header is 8 bytes long and each address 382 * occupies 16 bytes, so the option length must be 383 * greater than or equal to 24 bytes and an odd multiple 384 * of 8 bytes. See section 5.1 in RFC 6106. 385 */ 386 if (rdnss->nd_opt_rdnss_len < 3 || 387 rdnss->nd_opt_rdnss_len % 2 == 0) { 388 warnmsg(LOG_INFO, __func__, 389 "too short RDNSS option in RA from %s " 390 "was ignored.", 391 inet_ntop(AF_INET6, &from.sin6_addr, ntopbuf, 392 sizeof(ntopbuf))); 393 break; 394 } 395 396 addr = (struct in6_addr *)(void *)(raoptp + sizeof(*rdnss)); 397 while ((char *)addr < (char *)RA_OPT_NEXT_HDR(raoptp)) { 398 if (inet_ntop(AF_INET6, addr, ntopbuf, 399 sizeof(ntopbuf)) == NULL) { 400 warnmsg(LOG_INFO, __func__, 401 "an invalid address in RDNSS option" 402 " in RA from %s was ignored.", 403 inet_ntop(AF_INET6, &from.sin6_addr, 404 ntopbuf, sizeof(ntopbuf))); 405 addr++; 406 continue; 407 } 408 if (IN6_IS_ADDR_LINKLOCAL(addr)) 409 /* XXX: % has to be escaped here */ 410 l = snprintf(nsbuf, sizeof(nsbuf), 411 "%s%c%s", ntopbuf, 412 SCOPE_DELIMITER, 413 ifi->ifname); 414 else 415 l = snprintf(nsbuf, sizeof(nsbuf), 416 "%s", ntopbuf); 417 if (l < 0 || (size_t)l >= sizeof(nsbuf)) { 418 warnmsg(LOG_ERR, __func__, 419 "address copying error in " 420 "RDNSS option: %d.", l); 421 addr++; 422 continue; 423 } 424 warnmsg(LOG_DEBUG, __func__, "nsbuf = %s", 425 nsbuf); 426 427 newent_rao = 0; 428 rao = find_raopt(rai, ndo->nd_opt_type, nsbuf, 429 strlen(nsbuf)); 430 if (rao == NULL) { 431 ELM_MALLOC(rao, break); 432 rao->rao_type = ndo->nd_opt_type; 433 rao->rao_len = strlen(nsbuf); 434 rao->rao_msg = strdup(nsbuf); 435 if (rao->rao_msg == NULL) { 436 warnmsg(LOG_ERR, __func__, 437 "strdup failed: %s", 438 strerror(errno)); 439 free(rao); 440 addr++; 441 continue; 442 } 443 newent_rao = 1; 444 } 445 /* Set expiration timer */ 446 memset(&rao->rao_expire, 0, 447 sizeof(rao->rao_expire)); 448 memset(&lifetime, 0, sizeof(lifetime)); 449 lifetime.tv_sec = 450 ntohl(rdnss->nd_opt_rdnss_lifetime); 451 TS_ADD(&now, &lifetime, &rao->rao_expire); 452 453 if (newent_rao) 454 TAILQ_INSERT_TAIL(&rai->rai_ra_opt, 455 rao, rao_next); 456 addr++; 457 } 458 break; 459 case ND_OPT_DNSSL: 460 dnssl = (struct nd_opt_dnssl *)raoptp; 461 462 /* Optlen sanity check (Section 5.3.1 in RFC 6106) */ 463 if (dnssl->nd_opt_dnssl_len < 2) { 464 warnmsg(LOG_INFO, __func__, 465 "too short DNSSL option" 466 "in RA from %s was ignored.", 467 inet_ntop(AF_INET6, &from.sin6_addr, 468 ntopbuf, sizeof(ntopbuf))); 469 break; 470 } 471 472 /* 473 * Ensure NUL-termination in DNSSL in case of 474 * malformed field. 475 */ 476 p = (char *)RA_OPT_NEXT_HDR(raoptp); 477 *(p - 1) = '\0'; 478 479 p = raoptp + sizeof(*dnssl); 480 while (1 < (len = dname_labeldec(dname, sizeof(dname), 481 p))) { 482 /* length == 1 means empty string */ 483 warnmsg(LOG_DEBUG, __func__, "dname = %s", 484 dname); 485 486 newent_rao = 0; 487 rao = find_raopt(rai, ndo->nd_opt_type, dname, 488 strlen(dname)); 489 if (rao == NULL) { 490 ELM_MALLOC(rao, break); 491 rao->rao_type = ndo->nd_opt_type; 492 rao->rao_len = strlen(dname); 493 rao->rao_msg = strdup(dname); 494 if (rao->rao_msg == NULL) { 495 warnmsg(LOG_ERR, __func__, 496 "strdup failed: %s", 497 strerror(errno)); 498 free(rao); 499 addr++; 500 continue; 501 } 502 newent_rao = 1; 503 } 504 /* Set expiration timer */ 505 memset(&rao->rao_expire, 0, 506 sizeof(rao->rao_expire)); 507 memset(&lifetime, 0, sizeof(lifetime)); 508 lifetime.tv_sec = 509 ntohl(dnssl->nd_opt_dnssl_lifetime); 510 TS_ADD(&now, &lifetime, &rao->rao_expire); 511 512 if (newent_rao) 513 TAILQ_INSERT_TAIL(&rai->rai_ra_opt, 514 rao, rao_next); 515 p += len; 516 } 517 break; 518 default: 519 /* nothing to do for other options */ 520 break; 521 } 522 raoptp = (char *)RA_OPT_NEXT_HDR(raoptp); 523 } 524 if (newent_rai) 525 TAILQ_INSERT_TAIL(&ifi->ifi_rainfo, rai, rai_next); 526 527 ra_opt_handler(ifi); 528 ifi->racnt++; 529 530 switch (ifi->state) { 531 case IFS_IDLE: /* should be ignored */ 532 case IFS_DELAY: /* right? */ 533 break; 534 case IFS_PROBE: 535 ifi->state = IFS_IDLE; 536 ifi->probes = 0; 537 rtsol_timer_update(ifi); 538 break; 539 } 540} 541 542static char resstr_ns_prefix[] = "nameserver "; 543static char resstr_sh_prefix[] = "search "; 544static char resstr_nl[] = "\n"; 545static char resstr_sp[] = " "; 546 547int 548ra_opt_handler(struct ifinfo *ifi) 549{ 550 struct ra_opt *rao; 551 struct rainfo *rai; 552 struct script_msg *smp1, *smp2, *smp3; 553 struct timespec now; 554 struct script_msg_head_t sm_rdnss_head = 555 TAILQ_HEAD_INITIALIZER(sm_rdnss_head); 556 struct script_msg_head_t sm_dnssl_head = 557 TAILQ_HEAD_INITIALIZER(sm_dnssl_head); 558 559 int dcount, dlen; 560 561 dcount = 0; 562 dlen = strlen(resstr_sh_prefix) + strlen(resstr_nl); 563 clock_gettime(CLOCK_MONOTONIC_FAST, &now); 564 565 /* 566 * All options from multiple RAs with the same or different 567 * source addresses on a single interface will be gathered and 568 * handled, not overridden. [RFC 4861 6.3.4] 569 */ 570 TAILQ_FOREACH(rai, &ifi->ifi_rainfo, rai_next) { 571 TAILQ_FOREACH(rao, &rai->rai_ra_opt, rao_next) { 572 switch (rao->rao_type) { 573 case ND_OPT_RDNSS: 574 if (TS_CMP(&now, &rao->rao_expire, >)) { 575 warnmsg(LOG_INFO, __func__, 576 "expired rdnss entry: %s", 577 (char *)rao->rao_msg); 578 break; 579 } 580 ELM_MALLOC(smp1, continue); 581 ELM_MALLOC(smp2, goto free1); 582 ELM_MALLOC(smp3, goto free2); 583 smp1->sm_msg = resstr_ns_prefix; 584 TAILQ_INSERT_TAIL(&sm_rdnss_head, smp1, 585 sm_next); 586 smp2->sm_msg = rao->rao_msg; 587 TAILQ_INSERT_TAIL(&sm_rdnss_head, smp2, 588 sm_next); 589 smp3->sm_msg = resstr_nl; 590 TAILQ_INSERT_TAIL(&sm_rdnss_head, smp3, 591 sm_next); 592 ifi->ifi_rdnss = IFI_DNSOPT_STATE_RECEIVED; 593 break; 594 case ND_OPT_DNSSL: 595 if (TS_CMP(&now, &rao->rao_expire, >)) { 596 warnmsg(LOG_INFO, __func__, 597 "expired dnssl entry: %s", 598 (char *)rao->rao_msg); 599 break; 600 } 601 dcount++; 602 /* Check resolv.conf(5) restrictions. */ 603 if (dcount > 6) { 604 warnmsg(LOG_INFO, __func__, 605 "dnssl entry exceeding maximum count (%d>6)" 606 ": %s", dcount, (char *)rao->rao_msg); 607 break; 608 } 609 if (256 < dlen + strlen(rao->rao_msg) + 610 strlen(resstr_sp)) { 611 warnmsg(LOG_INFO, __func__, 612 "dnssl entry exceeding maximum length " 613 "(>256): %s", (char *)rao->rao_msg); 614 break; 615 } 616 ELM_MALLOC(smp1, continue); 617 ELM_MALLOC(smp2, goto free1); 618 if (TAILQ_EMPTY(&sm_dnssl_head)) { 619 ELM_MALLOC(smp3, goto free2); 620 smp3->sm_msg = resstr_sh_prefix; 621 TAILQ_INSERT_TAIL(&sm_dnssl_head, smp3, 622 sm_next); 623 } 624 smp1->sm_msg = rao->rao_msg; 625 TAILQ_INSERT_TAIL(&sm_dnssl_head, smp1, 626 sm_next); 627 smp2->sm_msg = resstr_sp; 628 TAILQ_INSERT_TAIL(&sm_dnssl_head, smp2, 629 sm_next); 630 dlen += strlen(rao->rao_msg) + 631 strlen(resstr_sp); 632 ifi->ifi_dnssl = IFI_DNSOPT_STATE_RECEIVED; 633 break; 634 } 635 continue; 636free2: 637 free(smp2); 638free1: 639 free(smp1); 640 } 641 /* Call the script for each information source. */ 642 if (uflag) 643 ra_opt_rdnss_dispatch(ifi, rai, &sm_rdnss_head, 644 &sm_dnssl_head); 645 } 646 /* Call the script for each interface. */ 647 if (!uflag) 648 ra_opt_rdnss_dispatch(ifi, NULL, &sm_rdnss_head, 649 &sm_dnssl_head); 650 return (0); 651} 652 653char * 654make_rsid(const char *ifname, const char *origin, struct rainfo *rai) 655{ 656 char hbuf[NI_MAXHOST]; 657 658 if (rai == NULL) 659 sprintf(rsid, "%s:%s", ifname, origin); 660 else { 661 if (!IN6_IS_ADDR_LINKLOCAL(&rai->rai_saddr.sin6_addr)) 662 return (NULL); 663 if (getnameinfo((struct sockaddr *)&rai->rai_saddr, 664 rai->rai_saddr.sin6_len, hbuf, sizeof(hbuf), NULL, 0, 665 NI_NUMERICHOST) != 0) 666 return (NULL); 667 sprintf(rsid, "%s:%s:[%s]", ifname, origin, hbuf); 668 } 669 warnmsg(LOG_DEBUG, __func__, "rsid = [%s]", rsid); 670 return (rsid); 671} 672 673int 674ra_opt_rdnss_dispatch(struct ifinfo *ifi, struct rainfo *rai, 675 struct script_msg_head_t *sm_rdnss_head, 676 struct script_msg_head_t *sm_dnssl_head) 677{ 678 struct script_msg *smp1; 679 const char *r; 680 int error; 681 682 error = 0; 683 /* Add \n for DNSSL list. */ 684 if (!TAILQ_EMPTY(sm_dnssl_head)) { 685 ELM_MALLOC(smp1, goto ra_opt_rdnss_freeit); 686 smp1->sm_msg = resstr_nl; 687 TAILQ_INSERT_TAIL(sm_dnssl_head, smp1, sm_next); 688 } 689 TAILQ_CONCAT(sm_rdnss_head, sm_dnssl_head, sm_next); 690 691 r = make_rsid(ifi->ifname, DNSINFO_ORIGIN_LABEL, uflag ? rai : NULL); 692 if (r == NULL) { 693 warnmsg(LOG_ERR, __func__, "make_rsid() failed. " 694 "Script was not invoked."); 695 error = 1; 696 goto ra_opt_rdnss_freeit; 697 } 698 if (!TAILQ_EMPTY(sm_rdnss_head)) 699 CALL_SCRIPT(RESADD, sm_rdnss_head); 700 else if (ifi->ifi_rdnss == IFI_DNSOPT_STATE_RECEIVED || 701 ifi->ifi_dnssl == IFI_DNSOPT_STATE_RECEIVED) { 702 CALL_SCRIPT(RESDEL, NULL); 703 ifi->ifi_rdnss = IFI_DNSOPT_STATE_NOINFO; 704 ifi->ifi_dnssl = IFI_DNSOPT_STATE_NOINFO; 705 } 706 707ra_opt_rdnss_freeit: 708 /* Clear script message queue. */ 709 if (!TAILQ_EMPTY(sm_rdnss_head)) { 710 while ((smp1 = TAILQ_FIRST(sm_rdnss_head)) != NULL) { 711 TAILQ_REMOVE(sm_rdnss_head, smp1, sm_next); 712 free(smp1); 713 } 714 } 715 if (!TAILQ_EMPTY(sm_dnssl_head)) { 716 while ((smp1 = TAILQ_FIRST(sm_dnssl_head)) != NULL) { 717 TAILQ_REMOVE(sm_dnssl_head, smp1, sm_next); 718 free(smp1); 719 } 720 } 721 return (error); 722} 723 724static struct ra_opt * 725find_raopt(struct rainfo *rai, int type, void *msg, size_t len) 726{ 727 struct ra_opt *rao; 728 729 TAILQ_FOREACH(rao, &rai->rai_ra_opt, rao_next) { 730 if (rao->rao_type == type && 731 rao->rao_len == strlen(msg) && 732 memcmp(rao->rao_msg, msg, len) == 0) 733 break; 734 } 735 736 return (rao); 737} 738 739static void 740call_script(const char *const argv[], struct script_msg_head_t *sm_head) 741{ 742 struct script_msg *smp; 743 ssize_t len; 744 int status, wfd; 745 746 if (argv[0] == NULL) 747 return; 748 749 wfd = cap_script_run(capscript, argv); 750 if (wfd == -1) { 751 warnmsg(LOG_ERR, __func__, 752 "failed to run %s: %s", argv[0], strerror(errno)); 753 return; 754 } 755 756 if (sm_head != NULL) { 757 TAILQ_FOREACH(smp, sm_head, sm_next) { 758 len = strlen(smp->sm_msg); 759 warnmsg(LOG_DEBUG, __func__, "write to child = %s(%zd)", 760 smp->sm_msg, len); 761 if (write(wfd, smp->sm_msg, len) != len) { 762 warnmsg(LOG_ERR, __func__, 763 "write to child failed: %s", 764 strerror(errno)); 765 break; 766 } 767 } 768 } 769 770 (void)close(wfd); 771 772 if (cap_script_wait(capscript, &status) != 0) 773 warnmsg(LOG_ERR, __func__, "wait(): %s", strerror(errno)); 774 else 775 warnmsg(LOG_DEBUG, __func__, "script \"%s\" status %d", 776 argv[0], status); 777} 778 779/* Decode domain name label encoding in RFC 1035 Section 3.1 */ 780static size_t 781dname_labeldec(char *dst, size_t dlen, const char *src) 782{ 783 size_t len; 784 const char *src_origin; 785 const char *src_last; 786 const char *dst_origin; 787 788 src_origin = src; 789 src_last = strchr(src, '\0'); 790 dst_origin = dst; 791 memset(dst, '\0', dlen); 792 while ((len = (*src++) & 0x3f) && 793 src + len <= src_last && 794 len + (dst == dst_origin ? 0 : 1) < dlen) { 795 if (dst != dst_origin) { 796 *dst++ = '.'; 797 dlen--; 798 } 799 warnmsg(LOG_DEBUG, __func__, "labellen = %zd", len); 800 memcpy(dst, src, len); 801 src += len; 802 dst += len; 803 dlen -= len; 804 } 805 *dst = '\0'; 806 807 /* 808 * XXX validate that domain name only contains valid characters 809 * for two reasons: 1) correctness, 2) we do not want to pass 810 * possible malicious, unescaped characters like `` to a script 811 * or program that could be exploited that way. 812 */ 813 814 return (src - src_origin); 815} 816