/* $OpenBSD: if.c,v 1.22 2009/07/11 09:51:53 rainer Exp $ */ /* $KAME: if.c,v 1.17 2001/01/21 15:27:30 itojun Exp $ */ /* * Copyright (C) 1995, 1996, 1997, and 1998 WIDE Project. * All rights reserved. * * Redistribution and use in source and binary forms, with or without * modification, are permitted provided that the following conditions * are met: * 1. Redistributions of source code must retain the above copyright * notice, this list of conditions and the following disclaimer. * 2. Redistributions in binary form must reproduce the above copyright * notice, this list of conditions and the following disclaimer in the * documentation and/or other materials provided with the distribution. * 3. Neither the name of the project nor the names of its contributors * may be used to endorse or promote products derived from this software * without specific prior written permission. * * THIS SOFTWARE IS PROVIDED BY THE PROJECT AND CONTRIBUTORS ``AS IS'' AND * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE * ARE DISCLAIMED. IN NO EVENT SHALL THE PROJECT OR CONTRIBUTORS BE LIABLE * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF * SUCH DAMAGE. */ #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include "rtadvd.h" #include "if.h" #include "log.h" #define ROUNDUP(a, size) \ (((a) & ((size)-1)) ? (1 + ((a) | ((size)-1))) : (a)) #define NEXT_SA(ap) (ap) = (struct sockaddr *) \ ((caddr_t)(ap) + ((ap)->sa_len ? ROUNDUP((ap)->sa_len,\ sizeof(u_long)) :\ sizeof(u_long))) struct if_msghdr **iflist; int iflist_init_ok; size_t ifblock_size; char *ifblock; static void get_iflist(char **buf, size_t *size); static void parse_iflist(struct if_msghdr ***ifmlist_p, char *buf, size_t bufsize); static void get_rtaddrs(int addrs, struct sockaddr *sa, struct sockaddr **rti_info) { int i; for (i = 0; i < RTAX_MAX; i++) { if (addrs & (1 << i)) { rti_info[i] = sa; NEXT_SA(sa); } else rti_info[i] = NULL; } } struct sockaddr_dl * if_nametosdl(char *name) { struct ifaddrs *ifap, *ifa; struct sockaddr_dl *sdl; if (getifaddrs(&ifap) != 0) return (NULL); for (ifa = ifap; ifa; ifa = ifa->ifa_next) { if (strcmp(ifa->ifa_name, name) != 0) continue; if (ifa->ifa_addr->sa_family != AF_LINK) continue; sdl = malloc(ifa->ifa_addr->sa_len); if (!sdl) continue; /*XXX*/ memcpy(sdl, ifa->ifa_addr, ifa->ifa_addr->sa_len); freeifaddrs(ifap); return (sdl); } freeifaddrs(ifap); return (NULL); } int if_getmtu(char *name) { struct ifaddrs *ifap, *ifa; struct if_data *ifd; u_long mtu = 0; if (getifaddrs(&ifap) < 0) return(0); for (ifa = ifap; ifa; ifa = ifa->ifa_next) { if (strcmp(ifa->ifa_name, name) == 0) { ifd = ifa->ifa_data; if (ifd) mtu = ifd->ifi_mtu; break; } } freeifaddrs(ifap); #ifdef SIOCGIFMTU /* XXX: this ifdef may not be necessary */ if (mtu == 0) { struct ifreq ifr; int s; if ((s = socket(AF_INET6, SOCK_DGRAM, 0)) < 0) return(0); ifr.ifr_addr.sa_family = AF_INET6; strncpy(ifr.ifr_name, name, sizeof(ifr.ifr_name)); if (ioctl(s, SIOCGIFMTU, (caddr_t)&ifr) < 0) { close(s); return(0); } close(s); mtu = ifr.ifr_mtu; } #endif return(mtu); } /* give interface index and its old flags, then new flags returned */ int if_getflags(int ifindex, int oifflags) { struct ifreq ifr; int s; if ((s = socket(AF_INET6, SOCK_DGRAM, 0)) < 0) { log_warn("socket"); return (oifflags & ~IFF_UP); } if_indextoname(ifindex, ifr.ifr_name); if (ioctl(s, SIOCGIFFLAGS, (caddr_t)&ifr) < 0) { log_warn("ioctl:SIOCGIFFLAGS: failed for %s", ifr.ifr_name); close(s); return (oifflags & ~IFF_UP); } close(s); return (ifr.ifr_flags); } #define ROUNDUP8(a) (1 + (((a) - 1) | 7)) int lladdropt_length(struct sockaddr_dl *sdl) { switch (sdl->sdl_type) { case IFT_ETHER: case IFT_FDDI: return(ROUNDUP8(ETHER_ADDR_LEN + 2)); default: return(0); } } void lladdropt_fill(struct sockaddr_dl *sdl, struct nd_opt_hdr *ndopt) { char *addr; ndopt->nd_opt_type = ND_OPT_SOURCE_LINKADDR; /* fixed */ switch (sdl->sdl_type) { case IFT_ETHER: case IFT_FDDI: ndopt->nd_opt_len = (ROUNDUP8(ETHER_ADDR_LEN + 2)) >> 3; addr = (char *)(ndopt + 1); memcpy(addr, LLADDR(sdl), ETHER_ADDR_LEN); break; default: log_warn("unsupported link type(%d)", sdl->sdl_type); exit(1); } return; } int rtbuf_len() { size_t len; int mib[6] = {CTL_NET, AF_ROUTE, 0, AF_INET6, NET_RT_DUMP, 0}; if (sysctl(mib, 6, NULL, &len, NULL, 0) < 0) return(-1); return(len); } #define FILTER_MATCH(type, filter) ((0x1 << type) & filter) #define SIN6(s) ((struct sockaddr_in6 *)(s)) #define SDL(s) ((struct sockaddr_dl *)(s)) char * get_next_msg(char *buf, char *lim, int ifindex, size_t *lenp, int filter) { struct rt_msghdr *rtm; struct ifa_msghdr *ifam; struct sockaddr *sa, *dst, *gw, *ifa, *rti_info[RTAX_MAX]; *lenp = 0; for (rtm = (struct rt_msghdr *)buf; rtm < (struct rt_msghdr *)lim; rtm = (struct rt_msghdr *)((char *)rtm + rtm->rtm_msglen)) { /* just for safety */ if (!rtm->rtm_msglen) { log_warnx("rtm_msglen is 0 (buf=%p lim=%p rtm=%p)", buf, lim, rtm); break; } if (rtm->rtm_version != RTM_VERSION) continue; if (FILTER_MATCH(rtm->rtm_type, filter) == 0) continue; switch (rtm->rtm_type) { case RTM_GET: case RTM_ADD: case RTM_DELETE: if (rtm->rtm_tableid != 0) continue; /* address related checks */ sa = (struct sockaddr *)((char *)rtm + rtm->rtm_hdrlen); get_rtaddrs(rtm->rtm_addrs, sa, rti_info); if ((dst = rti_info[RTAX_DST]) == NULL || dst->sa_family != AF_INET6) continue; if (IN6_IS_ADDR_LINKLOCAL(&SIN6(dst)->sin6_addr) || IN6_IS_ADDR_MULTICAST(&SIN6(dst)->sin6_addr)) continue; if ((gw = rti_info[RTAX_GATEWAY]) == NULL || gw->sa_family != AF_LINK) continue; if (ifindex && SDL(gw)->sdl_index != ifindex) continue; if (rti_info[RTAX_NETMASK] == NULL) continue; /* found */ *lenp = rtm->rtm_msglen; return (char *)rtm; /* NOTREACHED */ case RTM_NEWADDR: case RTM_DELADDR: ifam = (struct ifa_msghdr *)rtm; /* address related checks */ sa = (struct sockaddr *)(ifam + 1); get_rtaddrs(ifam->ifam_addrs, sa, rti_info); if ((ifa = rti_info[RTAX_IFA]) == NULL || (ifa->sa_family != AF_INET && ifa->sa_family != AF_INET6)) continue; if (ifa->sa_family == AF_INET6 && (IN6_IS_ADDR_LINKLOCAL(&SIN6(ifa)->sin6_addr) || IN6_IS_ADDR_MULTICAST(&SIN6(ifa)->sin6_addr))) continue; if (ifindex && ifam->ifam_index != ifindex) continue; /* found */ *lenp = ifam->ifam_msglen; return (char *)rtm; /* NOTREACHED */ case RTM_IFINFO: /* found */ *lenp = rtm->rtm_msglen; return (char *)rtm; /* NOTREACHED */ } } return (char *)rtm; } #undef FILTER_MATCH struct in6_addr * get_addr(char *buf) { struct rt_msghdr *rtm = (struct rt_msghdr *)buf; struct sockaddr *sa, *rti_info[RTAX_MAX]; sa = (struct sockaddr *)(buf + rtm->rtm_hdrlen); get_rtaddrs(rtm->rtm_addrs, sa, rti_info); return(&SIN6(rti_info[RTAX_DST])->sin6_addr); } int get_rtm_ifindex(char *buf) { struct rt_msghdr *rtm = (struct rt_msghdr *)buf; struct sockaddr *sa, *rti_info[RTAX_MAX]; sa = (struct sockaddr *)(buf + rtm->rtm_hdrlen); get_rtaddrs(rtm->rtm_addrs, sa, rti_info); return(((struct sockaddr_dl *)rti_info[RTAX_GATEWAY])->sdl_index); } int get_ifm_ifindex(char *buf) { struct if_msghdr *ifm = (struct if_msghdr *)buf; return ((int)ifm->ifm_index); } int get_ifam_ifindex(char *buf) { struct ifa_msghdr *ifam = (struct ifa_msghdr *)buf; return ((int)ifam->ifam_index); } int get_ifm_flags(char *buf) { struct if_msghdr *ifm = (struct if_msghdr *)buf; return (ifm->ifm_flags); } int get_prefixlen(char *buf) { struct rt_msghdr *rtm = (struct rt_msghdr *)buf; struct sockaddr *sa, *rti_info[RTAX_MAX]; u_char *p, *lim; sa = (struct sockaddr *)(buf + rtm->rtm_hdrlen); get_rtaddrs(rtm->rtm_addrs, sa, rti_info); sa = rti_info[RTAX_NETMASK]; p = (u_char *)(&SIN6(sa)->sin6_addr); lim = (u_char *)sa + sa->sa_len; return prefixlen(p, lim); } int prefixlen(u_char *p, u_char *lim) { int masklen; for (masklen = 0; p < lim; p++) { switch (*p) { case 0xff: masklen += 8; break; case 0xfe: masklen += 7; break; case 0xfc: masklen += 6; break; case 0xf8: masklen += 5; break; case 0xf0: masklen += 4; break; case 0xe0: masklen += 3; break; case 0xc0: masklen += 2; break; case 0x80: masklen += 1; break; case 0x00: break; default: return(-1); } } return(masklen); } int rtmsg_type(char *buf) { struct rt_msghdr *rtm = (struct rt_msghdr *)buf; return(rtm->rtm_type); } int rtmsg_len(char *buf) { struct rt_msghdr *rtm = (struct rt_msghdr *)buf; return(rtm->rtm_msglen); } int ifmsg_len(char *buf) { struct if_msghdr *ifm = (struct if_msghdr *)buf; return(ifm->ifm_msglen); } /* * alloc buffer and get if_msghdrs block from kernel, * and put them into the buffer */ static void get_iflist(char **buf, size_t *size) { int mib[6]; mib[0] = CTL_NET; mib[1] = PF_ROUTE; mib[2] = 0; mib[3] = AF_INET6; mib[4] = NET_RT_IFLIST; mib[5] = 0; if (sysctl(mib, 6, NULL, size, NULL, 0) < 0) fatal("sysctl: iflist size get failed"); if ((*buf = malloc(*size)) == NULL) fatal("malloc"); if (sysctl(mib, 6, *buf, size, NULL, 0) < 0) fatal("sysctl: iflist get failed"); return; } /* * alloc buffer and parse if_msghdrs block passed as arg, * and init the buffer as list of pointers ot each of the if_msghdr. */ static void parse_iflist(struct if_msghdr ***ifmlist_p, char *buf, size_t bufsize) { int iflentry_size, malloc_size; struct if_msghdr *ifm; struct ifa_msghdr *ifam; char *lim; /* * Estimate least size of an iflist entry, to be obtained from kernel. * Should add sizeof(sockaddr) ?? */ iflentry_size = sizeof(struct if_msghdr); /* roughly estimate max list size of pointers to each if_msghdr */ malloc_size = (bufsize/iflentry_size) * sizeof(size_t); if ((*ifmlist_p = (struct if_msghdr **)malloc(malloc_size)) == NULL) fatal("malloc"); lim = buf + bufsize; for (ifm = (struct if_msghdr *)buf; ifm < (struct if_msghdr *)lim;) { if (ifm->ifm_msglen == 0) { log_warn("ifm_msglen is 0 (buf=%p lim=%p ifm=%p)", buf, lim, ifm); return; } if (ifm->ifm_type == RTM_IFINFO) { if (ifm->ifm_version == RTM_VERSION) (*ifmlist_p)[ifm->ifm_index] = ifm; } else { log_warn("out of sync parsing NET_RT_IFLIST," " expected %d, got %d, msglen = %d," " buf:%p, ifm:%p, lim:%p", RTM_IFINFO, ifm->ifm_type, ifm->ifm_msglen, buf, ifm, lim); exit(1); } for (ifam = (struct ifa_msghdr *) ((char *)ifm + ifm->ifm_msglen); ifam < (struct ifa_msghdr *)lim; ifam = (struct ifa_msghdr *) ((char *)ifam + ifam->ifam_msglen)) { /* just for safety */ if (!ifam->ifam_msglen) { log_warnx("ifa_msglen is 0 " "(buf=%p lim=%p ifam=%p)", buf, lim, ifam); return; } if (ifam->ifam_type != RTM_NEWADDR) break; } ifm = (struct if_msghdr *)ifam; } } void init_iflist() { if (ifblock) { free(ifblock); ifblock_size = 0; } if (iflist) free(iflist); /* get iflist block from kernel */ get_iflist(&ifblock, &ifblock_size); /* make list of pointers to each if_msghdr */ parse_iflist(&iflist, ifblock, ifblock_size); }