1 /* $NetBSD: if.c,v 1.5 2000/05/23 11:37:59 itojun Exp $ */ 2 /* $KAME: if.c,v 1.8 2000/05/22 22:04:37 itojun 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 #ifdef __bsdi__ 43 # include <ifaddrs.h> 44 #endif 45 #ifdef __NetBSD__ 46 #include <net/if_ether.h> 47 #endif 48 #include <net/route.h> 49 #include <net/if_dl.h> 50 #include <netinet/in.h> 51 #include <netinet/icmp6.h> 52 #ifdef __bsdi__ 53 # include <netinet/if_ether.h> 54 #endif 55 #ifdef __OpenBSD__ 56 #include <netinet/if_ether.h> 57 #endif 58 #include <unistd.h> 59 #include <errno.h> 60 #include <stdlib.h> 61 #include <string.h> 62 #include <syslog.h> 63 #include "rtadvd.h" 64 #include "if.h" 65 66 #define ROUNDUP(a, size) \ 67 (((a) & ((size)-1)) ? (1 + ((a) | ((size)-1))) : (a)) 68 69 #define NEXT_SA(ap) (ap) = (struct sockaddr *) \ 70 ((caddr_t)(ap) + ((ap)->sa_len ? ROUNDUP((ap)->sa_len,\ 71 sizeof(u_long)) :\ 72 sizeof(u_long))) 73 74 struct if_msghdr **iflist; 75 int iflist_init_ok; 76 size_t ifblock_size; 77 char *ifblock; 78 79 static void get_iflist __P((char **buf, size_t *size)); 80 static void parse_iflist __P((struct if_msghdr ***ifmlist_p, char *buf, 81 size_t bufsize)); 82 83 static void 84 get_rtaddrs(int addrs, struct sockaddr *sa, struct sockaddr **rti_info) 85 { 86 int i; 87 88 for (i = 0; i < RTAX_MAX; i++) { 89 if (addrs & (1 << i)) { 90 rti_info[i] = sa; 91 NEXT_SA(sa); 92 } 93 else 94 rti_info[i] = NULL; 95 } 96 } 97 98 struct sockaddr_dl * 99 if_nametosdl(char *name) 100 { 101 int mib[6] = {CTL_NET, AF_ROUTE, 0, 0, NET_RT_IFLIST, 0}; 102 char *buf, *next, *lim; 103 size_t len; 104 struct if_msghdr *ifm; 105 struct sockaddr *sa, *rti_info[RTAX_MAX]; 106 struct sockaddr_dl *sdl = NULL, *ret_sdl; 107 108 if (sysctl(mib, 6, NULL, &len, NULL, 0) < 0) 109 return(NULL); 110 if ((buf = malloc(len)) == NULL) 111 return(NULL); 112 if (sysctl(mib, 6, buf, &len, NULL, 0) < 0) { 113 free(buf); 114 return(NULL); 115 } 116 117 lim = buf + len; 118 for (next = buf; next < lim; next += ifm->ifm_msglen) { 119 ifm = (struct if_msghdr *)next; 120 if (ifm->ifm_type == RTM_IFINFO) { 121 sa = (struct sockaddr *)(ifm + 1); 122 get_rtaddrs(ifm->ifm_addrs, sa, rti_info); 123 if ((sa = rti_info[RTAX_IFP]) != NULL) { 124 if (sa->sa_family == AF_LINK) { 125 sdl = (struct sockaddr_dl *)sa; 126 if (strlen(name) != sdl->sdl_nlen) 127 continue; /* not same len */ 128 if (strncmp(&sdl->sdl_data[0], 129 name, 130 sdl->sdl_nlen) == 0) { 131 break; 132 } 133 } 134 } 135 } 136 } 137 if (next == lim) { 138 /* search failed */ 139 free(buf); 140 return(NULL); 141 } 142 143 if ((ret_sdl = malloc(sdl->sdl_len)) == NULL) 144 return(NULL); 145 memcpy((caddr_t)ret_sdl, (caddr_t)sdl, sdl->sdl_len); 146 return(ret_sdl); 147 } 148 149 int 150 if_getmtu(char *name) 151 { 152 #ifndef __bsdi__ 153 struct ifreq ifr; 154 int s; 155 156 if ((s = socket(AF_INET6, SOCK_DGRAM, 0)) < 0) 157 return(0); 158 159 ifr.ifr_addr.sa_family = AF_INET6; 160 strncpy(ifr.ifr_name, name, sizeof(ifr.ifr_name)); 161 if (ioctl(s, SIOCGIFMTU, (caddr_t)&ifr) < 0) { 162 close(s); 163 return(0); 164 } 165 166 close(s); 167 168 return(ifr.ifr_mtu); 169 #else 170 struct ifaddrs *ifap, *ifa; 171 struct if_data *ifd; 172 173 if (getifaddrs(&ifap) < 0) 174 return(0); 175 for (ifa = ifap; ifa; ifa = ifa->ifa_next) { 176 if (strcmp(ifa->ifa_name, name) == 0) { 177 ifd = ifa->ifa_data; 178 freeifaddrs(ifap); 179 if (ifd) 180 return ifd->ifi_mtu; 181 else 182 return 0; 183 } 184 } 185 freeifaddrs(ifap); 186 return 0; 187 #endif 188 } 189 190 /* give interface index and its old flags, then new flags returned */ 191 int 192 if_getflags(int ifindex, int oifflags) 193 { 194 struct ifreq ifr; 195 int s; 196 197 if ((s = socket(AF_INET6, SOCK_DGRAM, 0)) < 0) { 198 syslog(LOG_ERR, "<%s> socket: %s", __FUNCTION__, 199 strerror(errno)); 200 return (oifflags & ~IFF_UP); 201 } 202 203 if_indextoname(ifindex, ifr.ifr_name); 204 if (ioctl(s, SIOCGIFFLAGS, (caddr_t)&ifr) < 0) { 205 syslog(LOG_ERR, "<%s> ioctl:SIOCGIFFLAGS: failed for %s", 206 __FUNCTION__, ifr.ifr_name); 207 close(s); 208 return (oifflags & ~IFF_UP); 209 } 210 return (ifr.ifr_flags); 211 } 212 213 #define ROUNDUP8(a) (1 + (((a) - 1) | 7)) 214 int 215 lladdropt_length(struct sockaddr_dl *sdl) 216 { 217 switch(sdl->sdl_type) { 218 case IFT_ETHER: 219 return(ROUNDUP8(ETHER_ADDR_LEN + 2)); 220 default: 221 return(0); 222 } 223 } 224 225 void 226 lladdropt_fill(struct sockaddr_dl *sdl, struct nd_opt_hdr *ndopt) 227 { 228 char *addr; 229 230 ndopt->nd_opt_type = ND_OPT_SOURCE_LINKADDR; /* fixed */ 231 232 switch(sdl->sdl_type) { 233 case IFT_ETHER: 234 ndopt->nd_opt_len = (ROUNDUP8(ETHER_ADDR_LEN + 2)) >> 3; 235 addr = (char *)(ndopt + 1); 236 memcpy(addr, LLADDR(sdl), ETHER_ADDR_LEN); 237 break; 238 default: 239 syslog(LOG_ERR, 240 "<%s> unsupported link type(%d)", 241 __FUNCTION__, sdl->sdl_type); 242 exit(1); 243 } 244 245 return; 246 } 247 248 int 249 rtbuf_len() 250 { 251 size_t len; 252 253 int mib[6] = {CTL_NET, AF_ROUTE, 0, AF_INET6, NET_RT_DUMP, 0}; 254 255 if (sysctl(mib, 6, NULL, &len, NULL, 0) < 0) 256 return(-1); 257 258 return(len); 259 } 260 261 int 262 get_rtinfo(char *buf, size_t *len) 263 { 264 int mib[6] = {CTL_NET, AF_ROUTE, 0, AF_INET6, NET_RT_DUMP, 0}; 265 266 if (sysctl(mib, 6, buf, len, NULL, 0) < 0) 267 return(-1); 268 269 return(0); 270 } 271 272 #define FILTER_MATCH(type, filter) ((0x1 << type) & filter) 273 #define SIN6(s) ((struct sockaddr_in6 *)(s)) 274 #define SDL(s) ((struct sockaddr_dl *)(s)) 275 char * 276 get_next_msg(char *buf, char *lim, int ifindex, size_t *lenp, int filter) 277 { 278 struct rt_msghdr *rtm; 279 struct ifa_msghdr *ifam; 280 struct sockaddr *sa, *dst, *gw, *ifa, *rti_info[RTAX_MAX]; 281 282 *lenp = 0; 283 for (rtm = (struct rt_msghdr *)buf; 284 rtm < (struct rt_msghdr *)lim; 285 rtm = (struct rt_msghdr *)(((char *)rtm) + rtm->rtm_msglen)) { 286 /* just for safety */ 287 if (!rtm->rtm_msglen) { 288 syslog(LOG_WARNING, "<%s> rtm_msglen is 0 " 289 "(buf=%p lim=%p rtm=%p)", __FUNCTION__, 290 buf, lim, rtm); 291 break; 292 } 293 if (FILTER_MATCH(rtm->rtm_type, filter) == 0) { 294 continue; 295 } 296 297 switch (rtm->rtm_type) { 298 case RTM_GET: 299 case RTM_ADD: 300 case RTM_DELETE: 301 /* address related checks */ 302 sa = (struct sockaddr *)(rtm + 1); 303 get_rtaddrs(rtm->rtm_addrs, sa, rti_info); 304 if ((dst = rti_info[RTAX_DST]) == NULL || 305 dst->sa_family != AF_INET6) 306 continue; 307 308 if (IN6_IS_ADDR_LINKLOCAL(&SIN6(dst)->sin6_addr) || 309 IN6_IS_ADDR_MULTICAST(&SIN6(dst)->sin6_addr)) 310 continue; 311 312 if ((gw = rti_info[RTAX_GATEWAY]) == NULL || 313 gw->sa_family != AF_LINK) 314 continue; 315 if (ifindex && SDL(gw)->sdl_index != ifindex) 316 continue; 317 318 if (rti_info[RTAX_NETMASK] == NULL) 319 continue; 320 321 /* found */ 322 *lenp = rtm->rtm_msglen; 323 return (char *)rtm; 324 /* NOTREACHED */ 325 case RTM_NEWADDR: 326 case RTM_DELADDR: 327 ifam = (struct ifa_msghdr *)rtm; 328 329 /* address related checks */ 330 sa = (struct sockaddr *)(ifam + 1); 331 get_rtaddrs(ifam->ifam_addrs, sa, rti_info); 332 if ((ifa = rti_info[RTAX_IFA]) == NULL || 333 (ifa->sa_family != AF_INET && 334 ifa->sa_family != AF_INET6)) 335 continue; 336 337 if (ifa->sa_family == AF_INET6 && 338 (IN6_IS_ADDR_LINKLOCAL(&SIN6(ifa)->sin6_addr) || 339 IN6_IS_ADDR_MULTICAST(&SIN6(ifa)->sin6_addr))) 340 continue; 341 342 if (ifindex && ifam->ifam_index != ifindex) 343 continue; 344 345 /* found */ 346 *lenp = ifam->ifam_msglen; 347 return (char *)rtm; 348 /* NOTREACHED */ 349 case RTM_IFINFO: 350 /* found */ 351 *lenp = rtm->rtm_msglen; 352 return (char *)rtm; 353 /* NOTREACHED */ 354 } 355 } 356 357 return (char *)rtm; 358 } 359 #undef FILTER_MATCH(type, filter) 360 361 struct in6_addr * 362 get_addr(char *buf) 363 { 364 struct rt_msghdr *rtm = (struct rt_msghdr *)buf; 365 struct sockaddr *sa, *rti_info[RTAX_MAX]; 366 367 sa = (struct sockaddr *)(rtm + 1); 368 get_rtaddrs(rtm->rtm_addrs, sa, rti_info); 369 370 return(&SIN6(rti_info[RTAX_DST])->sin6_addr); 371 } 372 373 int 374 get_rtm_ifindex(char *buf) 375 { 376 struct rt_msghdr *rtm = (struct rt_msghdr *)buf; 377 struct sockaddr *sa, *rti_info[RTAX_MAX]; 378 379 sa = (struct sockaddr *)(rtm + 1); 380 get_rtaddrs(rtm->rtm_addrs, sa, rti_info); 381 382 return(((struct sockaddr_dl *)rti_info[RTAX_GATEWAY])->sdl_index); 383 } 384 385 int 386 get_ifm_ifindex(char *buf) 387 { 388 struct if_msghdr *ifm = (struct if_msghdr *)buf; 389 390 return ((int)ifm->ifm_index); 391 } 392 393 int 394 get_ifam_ifindex(char *buf) 395 { 396 struct ifa_msghdr *ifam = (struct ifa_msghdr *)buf; 397 398 return ((int)ifam->ifam_index); 399 } 400 401 int 402 get_ifm_flags(char *buf) 403 { 404 struct if_msghdr *ifm = (struct if_msghdr *)buf; 405 406 return (ifm->ifm_flags); 407 } 408 409 int 410 get_prefixlen(char *buf) 411 { 412 struct rt_msghdr *rtm = (struct rt_msghdr *)buf; 413 struct sockaddr *sa, *rti_info[RTAX_MAX]; 414 int masklen; 415 u_char *p, *lim; 416 417 sa = (struct sockaddr *)(rtm + 1); 418 get_rtaddrs(rtm->rtm_addrs, sa, rti_info); 419 sa = rti_info[RTAX_NETMASK]; 420 421 p = (u_char *)(&SIN6(sa)->sin6_addr); 422 lim = (u_char *)sa + sa->sa_len; 423 for (masklen = 0; p < lim; p++) { 424 switch (*p) { 425 case 0xff: 426 masklen += 8; 427 break; 428 case 0xfe: 429 masklen += 7; 430 break; 431 case 0xfc: 432 masklen += 6; 433 break; 434 case 0xf8: 435 masklen += 5; 436 break; 437 case 0xf0: 438 masklen += 4; 439 break; 440 case 0xe0: 441 masklen += 3; 442 break; 443 case 0xc0: 444 masklen += 2; 445 break; 446 case 0x80: 447 masklen += 1; 448 break; 449 case 0x00: 450 break; 451 default: 452 return(-1); 453 } 454 } 455 456 return(masklen); 457 } 458 459 int 460 rtmsg_type(char *buf) 461 { 462 struct rt_msghdr *rtm = (struct rt_msghdr *)buf; 463 464 return(rtm->rtm_type); 465 } 466 467 int 468 rtmsg_len(char *buf) 469 { 470 struct rt_msghdr *rtm = (struct rt_msghdr *)buf; 471 472 return(rtm->rtm_msglen); 473 } 474 475 int 476 ifmsg_len(char *buf) 477 { 478 struct if_msghdr *ifm = (struct if_msghdr *)buf; 479 480 return(ifm->ifm_msglen); 481 } 482 483 /* 484 * alloc buffer and get if_msghdrs block from kernel, 485 * and put them into the buffer 486 */ 487 static void 488 get_iflist(char **buf, size_t *size) 489 { 490 int mib[6]; 491 492 mib[0] = CTL_NET; 493 mib[1] = PF_ROUTE; 494 mib[2] = 0; 495 mib[3] = AF_INET6; 496 mib[4] = NET_RT_IFLIST; 497 mib[5] = 0; 498 499 if (sysctl(mib, 6, NULL, size, NULL, 0) < 0) { 500 syslog(LOG_ERR, "<%s> sysctl: iflist size get failed", 501 __FUNCTION__); 502 exit(1); 503 } 504 if ((*buf = malloc(*size)) == NULL) { 505 syslog(LOG_ERR, "<%s> malloc failed", __FUNCTION__); 506 exit(1); 507 } 508 if (sysctl(mib, 6, *buf, size, NULL, 0) < 0) { 509 syslog(LOG_ERR, "<%s> sysctl: iflist get failed", 510 __FUNCTION__); 511 exit(1); 512 } 513 return; 514 } 515 516 /* 517 * alloc buffer and parse if_msghdrs block passed as arg, 518 * and init the buffer as list of pointers ot each of the if_msghdr. 519 */ 520 static void 521 parse_iflist(struct if_msghdr ***ifmlist_p, char *buf, size_t bufsize) 522 { 523 int iflentry_size, malloc_size; 524 struct if_msghdr *ifm; 525 struct ifa_msghdr *ifam; 526 char *lim; 527 528 /* 529 * Estimate least size of an iflist entry, to be obtained from kernel. 530 * Should add sizeof(sockaddr) ?? 531 */ 532 iflentry_size = sizeof(struct if_msghdr); 533 /* roughly estimate max list size of pointers to each if_msghdr */ 534 malloc_size = (bufsize/iflentry_size) * sizeof(size_t); 535 if ((*ifmlist_p = (struct if_msghdr **)malloc(malloc_size)) == NULL) { 536 syslog(LOG_ERR, "<%s> malloc failed", __FUNCTION__); 537 exit(1); 538 } 539 540 lim = buf + bufsize; 541 for (ifm = (struct if_msghdr *)buf; ifm < (struct if_msghdr *)lim;) { 542 if (ifm->ifm_msglen == 0) { 543 syslog(LOG_WARNING, "<%s> ifm_msglen is 0 " 544 "(buf=%p lim=%p ifm=%p)", __FUNCTION__, 545 buf, lim, ifm); 546 return; 547 } 548 549 if (ifm->ifm_type == RTM_IFINFO) { 550 (*ifmlist_p)[ifm->ifm_index] = ifm; 551 } else { 552 syslog(LOG_ERR, "out of sync parsing NET_RT_IFLIST\n" 553 "expected %d, got %d\n msglen = %d\n" 554 "buf:%p, ifm:%p, lim:%p\n", 555 RTM_IFINFO, ifm->ifm_type, ifm->ifm_msglen, 556 buf, ifm, lim); 557 exit (1); 558 } 559 for (ifam = (struct ifa_msghdr *) 560 ((char *)ifm + ifm->ifm_msglen); 561 ifam < (struct ifa_msghdr *)lim; 562 ifam = (struct ifa_msghdr *) 563 ((char *)ifam + ifam->ifam_msglen)) { 564 /* just for safety */ 565 if (!ifam->ifam_msglen) { 566 syslog(LOG_WARNING, "<%s> ifa_msglen is 0 " 567 "(buf=%p lim=%p ifam=%p)", __FUNCTION__, 568 buf, lim, ifam); 569 return; 570 } 571 if (ifam->ifam_type != RTM_NEWADDR) 572 break; 573 } 574 ifm = (struct if_msghdr *)ifam; 575 } 576 } 577 578 void 579 init_iflist() 580 { 581 if (ifblock) { 582 free(ifblock); 583 ifblock_size = 0; 584 } 585 if (iflist) 586 free(iflist); 587 /* get iflist block from kernel */ 588 get_iflist(&ifblock, &ifblock_size); 589 590 /* make list of pointers to each if_msghdr */ 591 parse_iflist(&iflist, ifblock, ifblock_size); 592 593 } 594