1 /* $NetBSD: if.c,v 1.6 2000/07/06 12:37:56 itojun Exp $ */ 2 /* $KAME: if.c,v 1.11 2000/07/06 08:20:04 jinmei Exp $ */ 3 4 /* 5 * Copyright (C) 1995, 1996, 1997, and 1998 WIDE Project. 6 * All rights reserved. 7 * 8 * Redistribution and use in source and binary forms, with or without 9 * modification, are permitted provided that the following conditions 10 * are met: 11 * 1. Redistributions of source code must retain the above copyright 12 * notice, this list of conditions and the following disclaimer. 13 * 2. Redistributions in binary form must reproduce the above copyright 14 * notice, this list of conditions and the following disclaimer in the 15 * documentation and/or other materials provided with the distribution. 16 * 3. Neither the name of the project nor the names of its contributors 17 * may be used to endorse or promote products derived from this software 18 * without specific prior written permission. 19 * 20 * THIS SOFTWARE IS PROVIDED BY THE PROJECT AND CONTRIBUTORS ``AS IS'' AND 21 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 22 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 23 * ARE DISCLAIMED. IN NO EVENT SHALL THE PROJECT OR CONTRIBUTORS BE LIABLE 24 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 25 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 26 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 27 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 28 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 29 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 30 * SUCH DAMAGE. 31 */ 32 33 #include <sys/param.h> 34 #include <sys/socket.h> 35 #include <sys/sysctl.h> 36 #include <sys/ioctl.h> 37 #include <net/if.h> 38 #include <net/if_types.h> 39 #ifdef __FreeBSD__ 40 # include <net/ethernet.h> 41 #endif 42 #include <ifaddrs.h> 43 #ifdef __NetBSD__ 44 #include <net/if_ether.h> 45 #endif 46 #include <net/route.h> 47 #include <net/if_dl.h> 48 #include <netinet/in.h> 49 #include <netinet/icmp6.h> 50 #ifdef __bsdi__ 51 # include <netinet/if_ether.h> 52 #endif 53 #ifdef __OpenBSD__ 54 #include <netinet/if_ether.h> 55 #endif 56 #include <unistd.h> 57 #include <errno.h> 58 #include <stdlib.h> 59 #include <string.h> 60 #include <syslog.h> 61 #include "rtadvd.h" 62 #include "if.h" 63 64 #define ROUNDUP(a, size) \ 65 (((a) & ((size)-1)) ? (1 + ((a) | ((size)-1))) : (a)) 66 67 #define NEXT_SA(ap) (ap) = (struct sockaddr *) \ 68 ((caddr_t)(ap) + ((ap)->sa_len ? ROUNDUP((ap)->sa_len,\ 69 sizeof(u_long)) :\ 70 sizeof(u_long))) 71 72 struct if_msghdr **iflist; 73 int iflist_init_ok; 74 size_t ifblock_size; 75 char *ifblock; 76 77 static void get_iflist __P((char **buf, size_t *size)); 78 static void parse_iflist __P((struct if_msghdr ***ifmlist_p, char *buf, 79 size_t bufsize)); 80 81 static void 82 get_rtaddrs(int addrs, struct sockaddr *sa, struct sockaddr **rti_info) 83 { 84 int i; 85 86 for (i = 0; i < RTAX_MAX; i++) { 87 if (addrs & (1 << i)) { 88 rti_info[i] = sa; 89 NEXT_SA(sa); 90 } 91 else 92 rti_info[i] = NULL; 93 } 94 } 95 96 struct sockaddr_dl * 97 if_nametosdl(char *name) 98 { 99 int mib[6] = {CTL_NET, AF_ROUTE, 0, 0, NET_RT_IFLIST, 0}; 100 char *buf, *next, *lim; 101 size_t len; 102 struct if_msghdr *ifm; 103 struct sockaddr *sa, *rti_info[RTAX_MAX]; 104 struct sockaddr_dl *sdl = NULL, *ret_sdl; 105 106 if (sysctl(mib, 6, NULL, &len, NULL, 0) < 0) 107 return(NULL); 108 if ((buf = malloc(len)) == NULL) 109 return(NULL); 110 if (sysctl(mib, 6, buf, &len, NULL, 0) < 0) { 111 free(buf); 112 return(NULL); 113 } 114 115 lim = buf + len; 116 for (next = buf; next < lim; next += ifm->ifm_msglen) { 117 ifm = (struct if_msghdr *)next; 118 if (ifm->ifm_type == RTM_IFINFO) { 119 sa = (struct sockaddr *)(ifm + 1); 120 get_rtaddrs(ifm->ifm_addrs, sa, rti_info); 121 if ((sa = rti_info[RTAX_IFP]) != NULL) { 122 if (sa->sa_family == AF_LINK) { 123 sdl = (struct sockaddr_dl *)sa; 124 if (strlen(name) != sdl->sdl_nlen) 125 continue; /* not same len */ 126 if (strncmp(&sdl->sdl_data[0], 127 name, 128 sdl->sdl_nlen) == 0) { 129 break; 130 } 131 } 132 } 133 } 134 } 135 if (next == lim) { 136 /* search failed */ 137 free(buf); 138 return(NULL); 139 } 140 141 if ((ret_sdl = malloc(sdl->sdl_len)) == NULL) 142 return(NULL); 143 memcpy((caddr_t)ret_sdl, (caddr_t)sdl, sdl->sdl_len); 144 return(ret_sdl); 145 } 146 147 int 148 if_getmtu(char *name) 149 { 150 #if 0 151 struct ifreq ifr; 152 int s; 153 154 if ((s = socket(AF_INET6, SOCK_DGRAM, 0)) < 0) 155 return(0); 156 157 ifr.ifr_addr.sa_family = AF_INET6; 158 strncpy(ifr.ifr_name, name, sizeof(ifr.ifr_name)); 159 if (ioctl(s, SIOCGIFMTU, (caddr_t)&ifr) < 0) { 160 close(s); 161 return(0); 162 } 163 164 close(s); 165 166 return(ifr.ifr_mtu); 167 #else 168 struct ifaddrs *ifap, *ifa; 169 struct if_data *ifd; 170 171 if (getifaddrs(&ifap) < 0) 172 return(0); 173 for (ifa = ifap; ifa; ifa = ifa->ifa_next) { 174 if (strcmp(ifa->ifa_name, name) == 0) { 175 ifd = ifa->ifa_data; 176 freeifaddrs(ifap); 177 if (ifd) 178 return ifd->ifi_mtu; 179 else 180 return 0; 181 } 182 } 183 freeifaddrs(ifap); 184 return 0; 185 #endif 186 } 187 188 /* give interface index and its old flags, then new flags returned */ 189 int 190 if_getflags(int ifindex, int oifflags) 191 { 192 struct ifreq ifr; 193 int s; 194 195 if ((s = socket(AF_INET6, SOCK_DGRAM, 0)) < 0) { 196 syslog(LOG_ERR, "<%s> socket: %s", __FUNCTION__, 197 strerror(errno)); 198 return (oifflags & ~IFF_UP); 199 } 200 201 if_indextoname(ifindex, ifr.ifr_name); 202 if (ioctl(s, SIOCGIFFLAGS, (caddr_t)&ifr) < 0) { 203 syslog(LOG_ERR, "<%s> ioctl:SIOCGIFFLAGS: failed for %s", 204 __FUNCTION__, ifr.ifr_name); 205 close(s); 206 return (oifflags & ~IFF_UP); 207 } 208 close(s); 209 return (ifr.ifr_flags); 210 } 211 212 #define ROUNDUP8(a) (1 + (((a) - 1) | 7)) 213 int 214 lladdropt_length(struct sockaddr_dl *sdl) 215 { 216 switch(sdl->sdl_type) { 217 case IFT_ETHER: 218 return(ROUNDUP8(ETHER_ADDR_LEN + 2)); 219 default: 220 return(0); 221 } 222 } 223 224 void 225 lladdropt_fill(struct sockaddr_dl *sdl, struct nd_opt_hdr *ndopt) 226 { 227 char *addr; 228 229 ndopt->nd_opt_type = ND_OPT_SOURCE_LINKADDR; /* fixed */ 230 231 switch(sdl->sdl_type) { 232 case IFT_ETHER: 233 ndopt->nd_opt_len = (ROUNDUP8(ETHER_ADDR_LEN + 2)) >> 3; 234 addr = (char *)(ndopt + 1); 235 memcpy(addr, LLADDR(sdl), ETHER_ADDR_LEN); 236 break; 237 default: 238 syslog(LOG_ERR, 239 "<%s> unsupported link type(%d)", 240 __FUNCTION__, sdl->sdl_type); 241 exit(1); 242 } 243 244 return; 245 } 246 247 int 248 rtbuf_len() 249 { 250 size_t len; 251 252 int mib[6] = {CTL_NET, AF_ROUTE, 0, AF_INET6, NET_RT_DUMP, 0}; 253 254 if (sysctl(mib, 6, NULL, &len, NULL, 0) < 0) 255 return(-1); 256 257 return(len); 258 } 259 260 int 261 get_rtinfo(char *buf, size_t *len) 262 { 263 int mib[6] = {CTL_NET, AF_ROUTE, 0, AF_INET6, NET_RT_DUMP, 0}; 264 265 if (sysctl(mib, 6, buf, len, NULL, 0) < 0) 266 return(-1); 267 268 return(0); 269 } 270 271 #define FILTER_MATCH(type, filter) ((0x1 << type) & filter) 272 #define SIN6(s) ((struct sockaddr_in6 *)(s)) 273 #define SDL(s) ((struct sockaddr_dl *)(s)) 274 char * 275 get_next_msg(char *buf, char *lim, int ifindex, size_t *lenp, int filter) 276 { 277 struct rt_msghdr *rtm; 278 struct ifa_msghdr *ifam; 279 struct sockaddr *sa, *dst, *gw, *ifa, *rti_info[RTAX_MAX]; 280 281 *lenp = 0; 282 for (rtm = (struct rt_msghdr *)buf; 283 rtm < (struct rt_msghdr *)lim; 284 rtm = (struct rt_msghdr *)(((char *)rtm) + rtm->rtm_msglen)) { 285 /* just for safety */ 286 if (!rtm->rtm_msglen) { 287 syslog(LOG_WARNING, "<%s> rtm_msglen is 0 " 288 "(buf=%p lim=%p rtm=%p)", __FUNCTION__, 289 buf, lim, rtm); 290 break; 291 } 292 if (FILTER_MATCH(rtm->rtm_type, filter) == 0) { 293 continue; 294 } 295 296 switch (rtm->rtm_type) { 297 case RTM_GET: 298 case RTM_ADD: 299 case RTM_DELETE: 300 /* address related checks */ 301 sa = (struct sockaddr *)(rtm + 1); 302 get_rtaddrs(rtm->rtm_addrs, sa, rti_info); 303 if ((dst = rti_info[RTAX_DST]) == NULL || 304 dst->sa_family != AF_INET6) 305 continue; 306 307 if (IN6_IS_ADDR_LINKLOCAL(&SIN6(dst)->sin6_addr) || 308 IN6_IS_ADDR_MULTICAST(&SIN6(dst)->sin6_addr)) 309 continue; 310 311 if ((gw = rti_info[RTAX_GATEWAY]) == NULL || 312 gw->sa_family != AF_LINK) 313 continue; 314 if (ifindex && SDL(gw)->sdl_index != ifindex) 315 continue; 316 317 if (rti_info[RTAX_NETMASK] == NULL) 318 continue; 319 320 /* found */ 321 *lenp = rtm->rtm_msglen; 322 return (char *)rtm; 323 /* NOTREACHED */ 324 case RTM_NEWADDR: 325 case RTM_DELADDR: 326 ifam = (struct ifa_msghdr *)rtm; 327 328 /* address related checks */ 329 sa = (struct sockaddr *)(ifam + 1); 330 get_rtaddrs(ifam->ifam_addrs, sa, rti_info); 331 if ((ifa = rti_info[RTAX_IFA]) == NULL || 332 (ifa->sa_family != AF_INET && 333 ifa->sa_family != AF_INET6)) 334 continue; 335 336 if (ifa->sa_family == AF_INET6 && 337 (IN6_IS_ADDR_LINKLOCAL(&SIN6(ifa)->sin6_addr) || 338 IN6_IS_ADDR_MULTICAST(&SIN6(ifa)->sin6_addr))) 339 continue; 340 341 if (ifindex && ifam->ifam_index != ifindex) 342 continue; 343 344 /* found */ 345 *lenp = ifam->ifam_msglen; 346 return (char *)rtm; 347 /* NOTREACHED */ 348 case RTM_IFINFO: 349 /* found */ 350 *lenp = rtm->rtm_msglen; 351 return (char *)rtm; 352 /* NOTREACHED */ 353 } 354 } 355 356 return (char *)rtm; 357 } 358 #undef FILTER_MATCH(type, filter) 359 360 struct in6_addr * 361 get_addr(char *buf) 362 { 363 struct rt_msghdr *rtm = (struct rt_msghdr *)buf; 364 struct sockaddr *sa, *rti_info[RTAX_MAX]; 365 366 sa = (struct sockaddr *)(rtm + 1); 367 get_rtaddrs(rtm->rtm_addrs, sa, rti_info); 368 369 return(&SIN6(rti_info[RTAX_DST])->sin6_addr); 370 } 371 372 int 373 get_rtm_ifindex(char *buf) 374 { 375 struct rt_msghdr *rtm = (struct rt_msghdr *)buf; 376 struct sockaddr *sa, *rti_info[RTAX_MAX]; 377 378 sa = (struct sockaddr *)(rtm + 1); 379 get_rtaddrs(rtm->rtm_addrs, sa, rti_info); 380 381 return(((struct sockaddr_dl *)rti_info[RTAX_GATEWAY])->sdl_index); 382 } 383 384 int 385 get_ifm_ifindex(char *buf) 386 { 387 struct if_msghdr *ifm = (struct if_msghdr *)buf; 388 389 return ((int)ifm->ifm_index); 390 } 391 392 int 393 get_ifam_ifindex(char *buf) 394 { 395 struct ifa_msghdr *ifam = (struct ifa_msghdr *)buf; 396 397 return ((int)ifam->ifam_index); 398 } 399 400 int 401 get_ifm_flags(char *buf) 402 { 403 struct if_msghdr *ifm = (struct if_msghdr *)buf; 404 405 return (ifm->ifm_flags); 406 } 407 408 int 409 get_prefixlen(char *buf) 410 { 411 struct rt_msghdr *rtm = (struct rt_msghdr *)buf; 412 struct sockaddr *sa, *rti_info[RTAX_MAX]; 413 int masklen; 414 u_char *p, *lim; 415 416 sa = (struct sockaddr *)(rtm + 1); 417 get_rtaddrs(rtm->rtm_addrs, sa, rti_info); 418 sa = rti_info[RTAX_NETMASK]; 419 420 p = (u_char *)(&SIN6(sa)->sin6_addr); 421 lim = (u_char *)sa + sa->sa_len; 422 for (masklen = 0; p < lim; p++) { 423 switch (*p) { 424 case 0xff: 425 masklen += 8; 426 break; 427 case 0xfe: 428 masklen += 7; 429 break; 430 case 0xfc: 431 masklen += 6; 432 break; 433 case 0xf8: 434 masklen += 5; 435 break; 436 case 0xf0: 437 masklen += 4; 438 break; 439 case 0xe0: 440 masklen += 3; 441 break; 442 case 0xc0: 443 masklen += 2; 444 break; 445 case 0x80: 446 masklen += 1; 447 break; 448 case 0x00: 449 break; 450 default: 451 return(-1); 452 } 453 } 454 455 return(masklen); 456 } 457 458 int 459 rtmsg_type(char *buf) 460 { 461 struct rt_msghdr *rtm = (struct rt_msghdr *)buf; 462 463 return(rtm->rtm_type); 464 } 465 466 int 467 rtmsg_len(char *buf) 468 { 469 struct rt_msghdr *rtm = (struct rt_msghdr *)buf; 470 471 return(rtm->rtm_msglen); 472 } 473 474 int 475 ifmsg_len(char *buf) 476 { 477 struct if_msghdr *ifm = (struct if_msghdr *)buf; 478 479 return(ifm->ifm_msglen); 480 } 481 482 /* 483 * alloc buffer and get if_msghdrs block from kernel, 484 * and put them into the buffer 485 */ 486 static void 487 get_iflist(char **buf, size_t *size) 488 { 489 int mib[6]; 490 491 mib[0] = CTL_NET; 492 mib[1] = PF_ROUTE; 493 mib[2] = 0; 494 mib[3] = AF_INET6; 495 mib[4] = NET_RT_IFLIST; 496 mib[5] = 0; 497 498 if (sysctl(mib, 6, NULL, size, NULL, 0) < 0) { 499 syslog(LOG_ERR, "<%s> sysctl: iflist size get failed", 500 __FUNCTION__); 501 exit(1); 502 } 503 if ((*buf = malloc(*size)) == NULL) { 504 syslog(LOG_ERR, "<%s> malloc failed", __FUNCTION__); 505 exit(1); 506 } 507 if (sysctl(mib, 6, *buf, size, NULL, 0) < 0) { 508 syslog(LOG_ERR, "<%s> sysctl: iflist get failed", 509 __FUNCTION__); 510 exit(1); 511 } 512 return; 513 } 514 515 /* 516 * alloc buffer and parse if_msghdrs block passed as arg, 517 * and init the buffer as list of pointers ot each of the if_msghdr. 518 */ 519 static void 520 parse_iflist(struct if_msghdr ***ifmlist_p, char *buf, size_t bufsize) 521 { 522 int iflentry_size, malloc_size; 523 struct if_msghdr *ifm; 524 struct ifa_msghdr *ifam; 525 char *lim; 526 527 /* 528 * Estimate least size of an iflist entry, to be obtained from kernel. 529 * Should add sizeof(sockaddr) ?? 530 */ 531 iflentry_size = sizeof(struct if_msghdr); 532 /* roughly estimate max list size of pointers to each if_msghdr */ 533 malloc_size = (bufsize/iflentry_size) * sizeof(size_t); 534 if ((*ifmlist_p = (struct if_msghdr **)malloc(malloc_size)) == NULL) { 535 syslog(LOG_ERR, "<%s> malloc failed", __FUNCTION__); 536 exit(1); 537 } 538 539 lim = buf + bufsize; 540 for (ifm = (struct if_msghdr *)buf; ifm < (struct if_msghdr *)lim;) { 541 if (ifm->ifm_msglen == 0) { 542 syslog(LOG_WARNING, "<%s> ifm_msglen is 0 " 543 "(buf=%p lim=%p ifm=%p)", __FUNCTION__, 544 buf, lim, ifm); 545 return; 546 } 547 548 if (ifm->ifm_type == RTM_IFINFO) { 549 (*ifmlist_p)[ifm->ifm_index] = ifm; 550 } else { 551 syslog(LOG_ERR, "out of sync parsing NET_RT_IFLIST\n" 552 "expected %d, got %d\n msglen = %d\n" 553 "buf:%p, ifm:%p, lim:%p\n", 554 RTM_IFINFO, ifm->ifm_type, ifm->ifm_msglen, 555 buf, ifm, lim); 556 exit (1); 557 } 558 for (ifam = (struct ifa_msghdr *) 559 ((char *)ifm + ifm->ifm_msglen); 560 ifam < (struct ifa_msghdr *)lim; 561 ifam = (struct ifa_msghdr *) 562 ((char *)ifam + ifam->ifam_msglen)) { 563 /* just for safety */ 564 if (!ifam->ifam_msglen) { 565 syslog(LOG_WARNING, "<%s> ifa_msglen is 0 " 566 "(buf=%p lim=%p ifam=%p)", __FUNCTION__, 567 buf, lim, ifam); 568 return; 569 } 570 if (ifam->ifam_type != RTM_NEWADDR) 571 break; 572 } 573 ifm = (struct if_msghdr *)ifam; 574 } 575 } 576 577 void 578 init_iflist() 579 { 580 if (ifblock) { 581 free(ifblock); 582 ifblock_size = 0; 583 } 584 if (iflist) 585 free(iflist); 586 /* get iflist block from kernel */ 587 get_iflist(&ifblock, &ifblock_size); 588 589 /* make list of pointers to each if_msghdr */ 590 parse_iflist(&iflist, ifblock, ifblock_size); 591 } 592