/* * Copyright (c) 2001-2003 * Fraunhofer Institute for Open Communication Systems (FhG Fokus). * All rights reserved. * * Author: Harti Brandt * * Redistribution of this software and documentation 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 or documentation 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 Institute 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 AND DOCUMENTATION IS PROVIDED BY FRAUNHOFER FOKUS * AND ITS 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 * FRAUNHOFER FOKUS OR ITS 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. * * $Begemot: bsnmp/snmp_mibII/mibII.c,v 1.18 2004/04/13 14:58:46 novo Exp $ * * Implementation of the standard interfaces and ip MIB. */ #include "mibII.h" #include "mibII_oid.h" #include /*****************************/ /* our module */ static struct lmodule *module; /* routing socket */ static int route; static void *route_fd; /* if-index allocator */ static u_int32_t next_if_index = 1; /* re-fetch arp table */ static int update_arp; static int in_update_arp; /* OR registrations */ static u_int ifmib_reg; static u_int ipmib_reg; static u_int tcpmib_reg; static u_int udpmib_reg; static u_int ipForward_reg; /*****************************/ /* list of all IP addresses */ struct mibifa_list mibifa_list = TAILQ_HEAD_INITIALIZER(mibifa_list); /* list of all interfaces */ struct mibif_list mibif_list = TAILQ_HEAD_INITIALIZER(mibif_list); /* list of dynamic interface names */ struct mibdynif_list mibdynif_list = SLIST_HEAD_INITIALIZER(mibdynif_list); /* list of all interface index mappings */ struct mibindexmap_list mibindexmap_list = STAILQ_HEAD_INITIALIZER(mibindexmap_list); /* list of all stacking entries */ struct mibifstack_list mibifstack_list = TAILQ_HEAD_INITIALIZER(mibifstack_list); /* list of all receive addresses */ struct mibrcvaddr_list mibrcvaddr_list = TAILQ_HEAD_INITIALIZER(mibrcvaddr_list); /* list of all NetToMedia entries */ struct mibarp_list mibarp_list = TAILQ_HEAD_INITIALIZER(mibarp_list); /* number of interfaces */ int32_t mib_if_number; /* last change of table */ u_int32_t mib_iftable_last_change; /* last change of stack table */ u_int32_t mib_ifstack_last_change; /* if this is set, one of our lists may be bad. refresh them when idle */ int mib_iflist_bad; /* network socket */ int mib_netsock; /* last time refreshed */ u_int32_t mibarpticks; /* info on system clocks */ struct clockinfo clockinfo; /* list of all New if registrations */ static struct newifreg_list newifreg_list = TAILQ_HEAD_INITIALIZER(newifreg_list); /*****************************/ static const struct asn_oid oid_ifMIB = OIDX_ifMIB; static const struct asn_oid oid_ipMIB = OIDX_ipMIB; static const struct asn_oid oid_tcpMIB = OIDX_tcpMIB; static const struct asn_oid oid_udpMIB = OIDX_udpMIB; static const struct asn_oid oid_ipForward = OIDX_ipForward; static const struct asn_oid oid_linkDown = OIDX_linkDown; static const struct asn_oid oid_linkUp = OIDX_linkUp; static const struct asn_oid oid_ifIndex = OIDX_ifIndex; /*****************************/ /* * Find an interface */ struct mibif * mib_find_if(u_int idx) { struct mibif *ifp; TAILQ_FOREACH(ifp, &mibif_list, link) if (ifp->index == idx) return (ifp); return (NULL); } struct mibif * mib_find_if_sys(u_int sysindex) { struct mibif *ifp; TAILQ_FOREACH(ifp, &mibif_list, link) if (ifp->sysindex == sysindex) return (ifp); return (NULL); } struct mibif * mib_find_if_name(const char *name) { struct mibif *ifp; TAILQ_FOREACH(ifp, &mibif_list, link) if (strcmp(ifp->name, name) == 0) return (ifp); return (NULL); } /* * Check whether an interface is dynamic. The argument may include the * unit number. This assumes, that the name part does NOT contain digits. */ int mib_if_is_dyn(const char *name) { size_t len; struct mibdynif *d; for (len = 0; name[len] != '\0' && isalpha(name[len]) ; len++) ; SLIST_FOREACH(d, &mibdynif_list, link) if (strlen(d->name) == len && strncmp(d->name, name, len) == 0) return (1); return (0); } /* set an interface name to dynamic mode */ void mib_if_set_dyn(const char *name) { struct mibdynif *d; SLIST_FOREACH(d, &mibdynif_list, link) if (strcmp(name, d->name) == 0) return; if ((d = malloc(sizeof(*d))) == NULL) err(1, NULL); strcpy(d->name, name); SLIST_INSERT_HEAD(&mibdynif_list, d, link); } /* * register for interface creations */ int mib_register_newif(int (*func)(struct mibif *), const struct lmodule *mod) { struct newifreg *reg; TAILQ_FOREACH(reg, &newifreg_list, link) if (reg->mod == mod) { reg->func = func; return (0); } if ((reg = malloc(sizeof(*reg))) == NULL) { syslog(LOG_ERR, "newifreg: %m"); return (-1); } reg->mod = mod; reg->func = func; TAILQ_INSERT_TAIL(&newifreg_list, reg, link); return (0); } void mib_unregister_newif(const struct lmodule *mod) { struct newifreg *reg; TAILQ_FOREACH(reg, &newifreg_list, link) if (reg->mod == mod) { TAILQ_REMOVE(&newifreg_list, reg, link); free(reg); return; } } struct mibif * mib_first_if(void) { return (TAILQ_FIRST(&mibif_list)); } struct mibif * mib_next_if(const struct mibif *ifp) { return (TAILQ_NEXT(ifp, link)); } /* * Change the admin status of an interface */ int mib_if_admin(struct mibif *ifp, int up) { struct ifreq ifr; strncpy(ifr.ifr_name, ifp->name, sizeof(ifr.ifr_name)); if (ioctl(mib_netsock, SIOCGIFFLAGS, &ifr) == -1) { syslog(LOG_ERR, "SIOCGIFFLAGS(%s): %m", ifp->name); return (-1); } if (up) ifr.ifr_flags |= IFF_UP; else ifr.ifr_flags &= ~IFF_UP; if (ioctl(mib_netsock, SIOCSIFFLAGS, &ifr) == -1) { syslog(LOG_ERR, "SIOCSIFFLAGS(%s): %m", ifp->name); return (-1); } (void)mib_fetch_ifmib(ifp); return (0); } /* * Generate a link up/down trap */ static void link_trap(struct mibif *ifp, int up) { struct snmp_value ifindex; ifindex.var = oid_ifIndex; ifindex.var.subs[ifindex.var.len++] = ifp->index; ifindex.syntax = SNMP_SYNTAX_INTEGER; ifindex.v.integer = ifp->index; snmp_send_trap(up ? &oid_linkUp : &oid_linkDown, &ifindex, NULL); } /* * Fetch new MIB data. */ int mib_fetch_ifmib(struct mibif *ifp) { int name[6]; size_t len; void *newmib; struct ifmibdata oldmib = ifp->mib; name[0] = CTL_NET; name[1] = PF_LINK; name[2] = NETLINK_GENERIC; name[3] = IFMIB_IFDATA; name[4] = ifp->sysindex; name[5] = IFDATA_GENERAL; len = sizeof(ifp->mib); if (sysctl(name, 6, &ifp->mib, &len, NULL, 0) == -1) { if (errno != ENOENT) syslog(LOG_WARNING, "sysctl(ifmib, %s) failed %m", ifp->name); return (-1); } if (ifp->trap_enable) { if (!(oldmib.ifmd_flags & IFF_UP)) { if (ifp->mib.ifmd_flags & IFF_UP) link_trap(ifp, 1); } else { if (!(ifp->mib.ifmd_flags & IFF_UP)) link_trap(ifp, 0); } } ifp->flags &= ~(MIBIF_HIGHSPEED | MIBIF_VERYHIGHSPEED); if (ifp->mib.ifmd_data.ifi_baudrate > 20000000) { ifp->flags |= MIBIF_HIGHSPEED; if (ifp->mib.ifmd_data.ifi_baudrate > 650000000) ifp->flags |= MIBIF_VERYHIGHSPEED; } /* * linkspecific MIB */ name[5] = IFDATA_LINKSPECIFIC; if (sysctl(name, 6, NULL, &len, NULL, 0) == -1) { syslog(LOG_WARNING, "sysctl linkmib estimate (%s): %m", ifp->name); if (ifp->specmib != NULL) { ifp->specmib = NULL; ifp->specmiblen = 0; } goto out; } if (len == 0) { if (ifp->specmib != NULL) { ifp->specmib = NULL; ifp->specmiblen = 0; } goto out; } if (ifp->specmiblen != len) { if ((newmib = realloc(ifp->specmib, len)) == NULL) { ifp->specmib = NULL; ifp->specmiblen = 0; goto out; } ifp->specmib = newmib; ifp->specmiblen = len; } if (sysctl(name, 6, ifp->specmib, &len, NULL, 0) == -1) { syslog(LOG_WARNING, "sysctl linkmib (%s): %m", ifp->name); if (ifp->specmib != NULL) { ifp->specmib = NULL; ifp->specmiblen = 0; } } out: ifp->mibtick = get_ticks(); return (0); } /* find first/next address for a given interface */ struct mibifa * mib_first_ififa(const struct mibif *ifp) { struct mibifa *ifa; TAILQ_FOREACH(ifa, &mibifa_list, link) if (ifp->index == ifa->ifindex) return (ifa); return (NULL); } struct mibifa * mib_next_ififa(struct mibifa *ifa0) { struct mibifa *ifa; ifa = ifa0; while ((ifa = TAILQ_NEXT(ifa, link)) != NULL) if (ifa->ifindex == ifa0->ifindex) return (ifa); return (NULL); } /* * Allocate a new IFA */ static struct mibifa * alloc_ifa(u_int ifindex, struct in_addr addr) { struct mibifa *ifa; u_int32_t ha; if ((ifa = malloc(sizeof(struct mibifa))) == NULL) { syslog(LOG_ERR, "ifa: %m"); return (NULL); } ifa->inaddr = addr; ifa->ifindex = ifindex; ha = ntohl(ifa->inaddr.s_addr); ifa->index.len = 4; ifa->index.subs[0] = (ha >> 24) & 0xff; ifa->index.subs[1] = (ha >> 16) & 0xff; ifa->index.subs[2] = (ha >> 8) & 0xff; ifa->index.subs[3] = (ha >> 0) & 0xff; ifa->flags = 0; ifa->inbcast.s_addr = 0; ifa->inmask.s_addr = 0xffffffff; INSERT_OBJECT_OID(ifa, &mibifa_list); return (ifa); } /* * Delete an interface address */ static void destroy_ifa(struct mibifa *ifa) { TAILQ_REMOVE(&mibifa_list, ifa, link); free(ifa); } /* * Helper routine to extract the sockaddr structures from a routing * socket message. */ void mib_extract_addrs(int addrs, u_char *info, struct sockaddr **out) { u_int i; for (i = 0; i < RTAX_MAX; i++) { if ((addrs & (1 << i)) != 0) { *out = (struct sockaddr *)info; info += roundup((*out)->sa_len, sizeof(long)); } else *out = NULL; out++; } } /* * save the phys address of an interface. Handle receive address entries here. */ static void get_physaddr(struct mibif *ifp, struct sockaddr_dl *sdl, u_char *ptr) { u_char *np; struct mibrcvaddr *rcv; if (sdl->sdl_alen == 0) { /* no address */ if (ifp->physaddrlen != 0) { if ((rcv = mib_find_rcvaddr(ifp->index, ifp->physaddr, ifp->physaddrlen)) != NULL) mib_rcvaddr_delete(rcv); free(ifp->physaddr); ifp->physaddr = NULL; ifp->physaddrlen = 0; } return; } if (ifp->physaddrlen != sdl->sdl_alen) { /* length changed */ if (ifp->physaddrlen) { /* delete olf receive address */ if ((rcv = mib_find_rcvaddr(ifp->index, ifp->physaddr, ifp->physaddrlen)) != NULL) mib_rcvaddr_delete(rcv); } if ((np = realloc(ifp->physaddr, sdl->sdl_alen)) == NULL) { free(ifp->physaddr); ifp->physaddr = NULL; ifp->physaddrlen = 0; return; } ifp->physaddr = np; ifp->physaddrlen = sdl->sdl_alen; } else if (memcmp(ifp->physaddr, ptr, ifp->physaddrlen) == 0) { /* no change */ return; } else { /* address changed */ /* delete olf receive address */ if ((rcv = mib_find_rcvaddr(ifp->index, ifp->physaddr, ifp->physaddrlen)) != NULL) mib_rcvaddr_delete(rcv); } memcpy(ifp->physaddr, ptr, ifp->physaddrlen); /* make new receive address */ if ((rcv = mib_rcvaddr_create(ifp, ifp->physaddr, ifp->physaddrlen)) != NULL) rcv->flags |= MIBRCVADDR_HW; } /* * Free an interface */ static void mibif_free(struct mibif *ifp) { struct mibindexmap *map; struct mibifa *ifa, *ifa1; struct mibrcvaddr *rcv, *rcv1; struct mibarp *at, *at1; if (ifp->xnotify != NULL) (*ifp->xnotify)(ifp, MIBIF_NOTIFY_DESTROY, ifp->xnotify_data); (void)mib_ifstack_delete(ifp, NULL); (void)mib_ifstack_delete(NULL, ifp); TAILQ_REMOVE(&mibif_list, ifp, link); if (ifp->physaddr != NULL) free(ifp->physaddr); if (ifp->specmib != NULL) free(ifp->specmib); STAILQ_FOREACH(map, &mibindexmap_list, link) if (map->mibif == ifp) { map->mibif = NULL; break; } /* purge interface addresses */ ifa = TAILQ_FIRST(&mibifa_list); while (ifa != NULL) { ifa1 = TAILQ_NEXT(ifa, link); if (ifa->ifindex == ifp->index) destroy_ifa(ifa); ifa = ifa1; } /* purge receive addresses */ rcv = TAILQ_FIRST(&mibrcvaddr_list); while (rcv != NULL) { rcv1 = TAILQ_NEXT(rcv, link); if (rcv->ifindex == ifp->index) mib_rcvaddr_delete(rcv); rcv = rcv1; } /* purge ARP entries */ at = TAILQ_FIRST(&mibarp_list); while (at != NULL) { at1 = TAILQ_NEXT(at, link); if (at->index.subs[0] == ifp->index) mib_arp_delete(at); at = at1; } free(ifp); mib_if_number--; mib_iftable_last_change = this_tick; } /* * Create a new interface */ static struct mibif * mibif_create(u_int sysindex, const char *name) { struct mibif *ifp; struct mibindexmap *map; if ((ifp = malloc(sizeof(*ifp))) == NULL) { syslog(LOG_WARNING, "%s: %m", __func__); return (NULL); } memset(ifp, 0, sizeof(*ifp)); ifp->sysindex = sysindex; strcpy(ifp->name, name); strcpy(ifp->descr, name); map = NULL; if (!mib_if_is_dyn(ifp->name)) { /* non-dynamic. look whether we know the interface */ STAILQ_FOREACH(map, &mibindexmap_list, link) if (strcmp(map->name, ifp->name) == 0) { ifp->index = map->ifindex; map->mibif = ifp; break; } /* assume it has a connector if it is not dynamic */ ifp->has_connector = 1; ifp->trap_enable = 1; } if (map == NULL) { /* new interface - get new index */ if (next_if_index > 0x7fffffff) errx(1, "ifindex wrap"); if ((map = malloc(sizeof(*map))) == NULL) { syslog(LOG_ERR, "ifmap: %m"); free(ifp); return (NULL); } map->ifindex = next_if_index++; map->sysindex = ifp->sysindex; strcpy(map->name, ifp->name); map->mibif = ifp; STAILQ_INSERT_TAIL(&mibindexmap_list, map, link); } else { /* re-instantiate. Introduce a counter discontinuity */ ifp->counter_disc = get_ticks(); } ifp->index = map->ifindex; INSERT_OBJECT_INT(ifp, &mibif_list); mib_if_number++; mib_iftable_last_change = this_tick; /* instantiate default ifStack entries */ (void)mib_ifstack_create(ifp, NULL); (void)mib_ifstack_create(NULL, ifp); return (ifp); } /* * Inform all interested parties about a new interface */ static void notify_newif(struct mibif *ifp) { struct newifreg *reg; TAILQ_FOREACH(reg, &newifreg_list, link) if ((*reg->func)(ifp)) return; } /* * This is called for new interfaces after we have fetched the interface * MIB. If this is a broadcast interface try to guess the broadcast address * depending on the interface type. */ static void check_llbcast(struct mibif *ifp) { static u_char ether_bcast[6] = { 0xff, 0xff, 0xff, 0xff, 0xff, 0xff }; static u_char arcnet_bcast = 0; struct mibrcvaddr *rcv; if (!(ifp->mib.ifmd_flags & IFF_BROADCAST)) return; switch (ifp->mib.ifmd_data.ifi_type) { case IFT_ETHER: case IFT_FDDI: case IFT_ISO88025: if (mib_find_rcvaddr(ifp->index, ether_bcast, 6) == NULL && (rcv = mib_rcvaddr_create(ifp, ether_bcast, 6)) != NULL) rcv->flags |= MIBRCVADDR_BCAST; break; case IFT_ARCNET: if (mib_find_rcvaddr(ifp->index, &arcnet_bcast, 1) == NULL && (rcv = mib_rcvaddr_create(ifp, &arcnet_bcast, 1)) != NULL) rcv->flags |= MIBRCVADDR_BCAST; break; } } /* * Retrieve the current interface list from the system. */ void mib_refresh_iflist(void) { struct mibif *ifp, *ifp1; size_t len; u_short idx; int name[6]; int count; struct ifmibdata mib; TAILQ_FOREACH(ifp, &mibif_list, link) ifp->flags &= ~MIBIF_FOUND; len = sizeof(count); if (sysctlbyname("net.link.generic.system.ifcount", &count, &len, NULL, 0) == -1) { syslog(LOG_ERR, "ifcount: %m"); return; } name[0] = CTL_NET; name[1] = PF_LINK; name[2] = NETLINK_GENERIC; name[3] = IFMIB_IFDATA; name[5] = IFDATA_GENERAL; for (idx = 1; idx <= count; idx++) { name[4] = idx; len = sizeof(mib); if (sysctl(name, 6, &mib, &len, NULL, 0) == -1) { if (errno == ENOENT) continue; syslog(LOG_ERR, "ifmib(%u): %m", idx); return; } if ((ifp = mib_find_if_sys(idx)) != NULL) { ifp->flags |= MIBIF_FOUND; continue; } /* Unknown interface - create */ if ((ifp = mibif_create(idx, mib.ifmd_name)) != NULL) { ifp->flags |= MIBIF_FOUND; (void)mib_fetch_ifmib(ifp); check_llbcast(ifp); notify_newif(ifp); } } /* * Purge interfaces that disappeared */ ifp = TAILQ_FIRST(&mibif_list); while (ifp != NULL) { ifp1 = TAILQ_NEXT(ifp, link); if (!(ifp->flags & MIBIF_FOUND)) mibif_free(ifp); ifp = ifp1; } } /* * Find an interface address */ struct mibifa * mib_find_ifa(struct in_addr addr) { struct mibifa *ifa; TAILQ_FOREACH(ifa, &mibifa_list, link) if (ifa->inaddr.s_addr == addr.s_addr) return (ifa); return (NULL); } /* * Process a new ARP entry */ static void process_arp(const struct rt_msghdr *rtm, const struct sockaddr_dl *sdl, const struct sockaddr_in *sa) { struct mibif *ifp; struct mibarp *at; /* IP arp table entry */ if (sdl->sdl_alen == 0) { update_arp = 1; return; } if ((ifp = mib_find_if_sys(sdl->sdl_index)) == NULL) return; /* have a valid entry */ if ((at = mib_find_arp(ifp, sa->sin_addr)) == NULL && (at = mib_arp_create(ifp, sa->sin_addr, sdl->sdl_data + sdl->sdl_nlen, sdl->sdl_alen)) == NULL) return; if (rtm->rtm_rmx.rmx_expire == 0) at->flags |= MIBARP_PERM; else at->flags &= ~MIBARP_PERM; at->flags |= MIBARP_FOUND; } /* * Handle a routing socket message. */ static void handle_rtmsg(struct rt_msghdr *rtm) { struct sockaddr *addrs[RTAX_MAX]; struct if_msghdr *ifm; struct ifa_msghdr *ifam; struct ifma_msghdr *ifmam; #ifdef RTM_IFANNOUNCE struct if_announcemsghdr *ifan; #endif struct mibif *ifp; struct sockaddr_dl *sdl; struct sockaddr_in *sa; struct mibifa *ifa; struct mibrcvaddr *rcv; u_char *ptr; if (rtm->rtm_version != RTM_VERSION) { syslog(LOG_ERR, "Bogus RTM version %u", rtm->rtm_version); return; } switch (rtm->rtm_type) { case RTM_NEWADDR: ifam = (struct ifa_msghdr *)rtm; mib_extract_addrs(ifam->ifam_addrs, (u_char *)(ifam + 1), addrs); if (addrs[RTAX_IFA] == NULL || addrs[RTAX_NETMASK] == NULL) break; sa = (struct sockaddr_in *)(void *)addrs[RTAX_IFA]; if ((ifa = mib_find_ifa(sa->sin_addr)) == NULL) { /* unknown address */ if ((ifp = mib_find_if_sys(ifam->ifam_index)) == NULL) { syslog(LOG_WARNING, "RTM_NEWADDR for unknown " "interface %u", ifam->ifam_index); break; } if ((ifa = alloc_ifa(ifp->index, sa->sin_addr)) == NULL) break; } sa = (struct sockaddr_in *)(void *)addrs[RTAX_NETMASK]; ifa->inmask = sa->sin_addr; if (addrs[RTAX_BRD] != NULL) { sa = (struct sockaddr_in *)(void *)addrs[RTAX_BRD]; ifa->inbcast = sa->sin_addr; } ifa->flags |= MIBIFA_FOUND; break; case RTM_DELADDR: ifam = (struct ifa_msghdr *)rtm; mib_extract_addrs(ifam->ifam_addrs, (u_char *)(ifam + 1), addrs); if (addrs[RTAX_IFA] == NULL) break; sa = (struct sockaddr_in *)(void *)addrs[RTAX_IFA]; if ((ifa = mib_find_ifa(sa->sin_addr)) != NULL) { ifa->flags |= MIBIFA_FOUND; if (!(ifa->flags & MIBIFA_DESTROYED)) destroy_ifa(ifa); } break; case RTM_NEWMADDR: ifmam = (struct ifma_msghdr *)rtm; mib_extract_addrs(ifmam->ifmam_addrs, (u_char *)(ifmam + 1), addrs); if (addrs[RTAX_IFA] == NULL || addrs[RTAX_IFA]->sa_family != AF_LINK) break; sdl = (struct sockaddr_dl *)(void *)addrs[RTAX_IFA]; if ((rcv = mib_find_rcvaddr(sdl->sdl_index, sdl->sdl_data + sdl->sdl_nlen, sdl->sdl_alen)) == NULL) { /* unknown address */ if ((ifp = mib_find_if_sys(sdl->sdl_index)) == NULL) { syslog(LOG_WARNING, "RTM_NEWMADDR for unknown " "interface %u", sdl->sdl_index); break; } if ((rcv = mib_rcvaddr_create(ifp, sdl->sdl_data + sdl->sdl_nlen, sdl->sdl_alen)) == NULL) break; rcv->flags |= MIBRCVADDR_VOLATILE; } rcv->flags |= MIBRCVADDR_FOUND; break; case RTM_DELMADDR: ifmam = (struct ifma_msghdr *)rtm; mib_extract_addrs(ifmam->ifmam_addrs, (u_char *)(ifmam + 1), addrs); if (addrs[RTAX_IFA] == NULL || addrs[RTAX_IFA]->sa_family != AF_LINK) break; sdl = (struct sockaddr_dl *)(void *)addrs[RTAX_IFA]; if ((rcv = mib_find_rcvaddr(sdl->sdl_index, sdl->sdl_data + sdl->sdl_nlen, sdl->sdl_alen)) != NULL) mib_rcvaddr_delete(rcv); break; case RTM_IFINFO: ifm = (struct if_msghdr *)rtm; mib_extract_addrs(ifm->ifm_addrs, (u_char *)(ifm + 1), addrs); if ((ifp = mib_find_if_sys(ifm->ifm_index)) == NULL) break; if (addrs[RTAX_IFP] != NULL && addrs[RTAX_IFP]->sa_family == AF_LINK) { sdl = (struct sockaddr_dl *)(void *)addrs[RTAX_IFP]; ptr = sdl->sdl_data + sdl->sdl_nlen; get_physaddr(ifp, sdl, ptr); } (void)mib_fetch_ifmib(ifp); break; #ifdef RTM_IFANNOUNCE case RTM_IFANNOUNCE: ifan = (struct if_announcemsghdr *)rtm; ifp = mib_find_if_sys(ifan->ifan_index); switch (ifan->ifan_what) { case IFAN_ARRIVAL: if (ifp == NULL && (ifp = mibif_create(ifan->ifan_index, ifan->ifan_name)) != NULL) { (void)mib_fetch_ifmib(ifp); check_llbcast(ifp); notify_newif(ifp); } break; case IFAN_DEPARTURE: if (ifp != NULL) mibif_free(ifp); break; } break; #endif case RTM_GET: mib_extract_addrs(rtm->rtm_addrs, (u_char *)(rtm + 1), addrs); if (rtm->rtm_flags & RTF_LLINFO) { if (addrs[RTAX_DST] == NULL || addrs[RTAX_GATEWAY] == NULL || addrs[RTAX_DST]->sa_family != AF_INET || addrs[RTAX_GATEWAY]->sa_family != AF_LINK) break; process_arp(rtm, (struct sockaddr_dl *)(void *)addrs[RTAX_GATEWAY], (struct sockaddr_in *)(void *)addrs[RTAX_DST]); } break; case RTM_ADD: mib_extract_addrs(rtm->rtm_addrs, (u_char *)(rtm + 1), addrs); if (rtm->rtm_flags & RTF_LLINFO) { if (addrs[RTAX_DST] == NULL || addrs[RTAX_GATEWAY] == NULL || addrs[RTAX_DST]->sa_family != AF_INET || addrs[RTAX_GATEWAY]->sa_family != AF_LINK) break; process_arp(rtm, (struct sockaddr_dl *)(void *)addrs[RTAX_GATEWAY], (struct sockaddr_in *)(void *)addrs[RTAX_DST]); } break; } } /* * Fetch the routing table via sysctl */ u_char * mib_fetch_rtab(int af, int info, int arg, size_t *lenp) { int name[6]; u_char *buf; name[0] = CTL_NET; name[1] = PF_ROUTE; name[2] = 0; name[3] = af; name[4] = info; name[5] = arg; *lenp = 0; if (sysctl(name, 6, NULL, lenp, NULL, 0) == -1) { syslog(LOG_ERR, "sysctl estimate (%d,%d,%d,%d,%d,%d): %m", name[0], name[1], name[2], name[3], name[4], name[5]); return (NULL); } if (*lenp == 0) return (NULL); if ((buf = malloc(*lenp)) == NULL) { syslog(LOG_ERR, "sysctl buffer: %m"); return (NULL); } if (sysctl(name, 6, buf, lenp, NULL, 0) == -1) { syslog(LOG_ERR, "sysctl get: %m"); free(buf); return (NULL); } return (buf); } /* * Update the following info: interface, interface addresses, interface * receive addresses, arp-table. * This does not change the interface list itself. */ static void update_ifa_info(void) { u_char *buf, *next; struct rt_msghdr *rtm; struct mibifa *ifa, *ifa1; struct mibrcvaddr *rcv, *rcv1; size_t needed; static const int infos[][3] = { { 0, NET_RT_IFLIST, 0 }, #ifdef NET_RT_IFMALIST { AF_LINK, NET_RT_IFMALIST, 0 }, #endif }; u_int i; TAILQ_FOREACH(ifa, &mibifa_list, link) ifa->flags &= ~MIBIFA_FOUND; TAILQ_FOREACH(rcv, &mibrcvaddr_list, link) rcv->flags &= ~MIBRCVADDR_FOUND; for (i = 0; i < sizeof(infos) / sizeof(infos[0]); i++) { if ((buf = mib_fetch_rtab(infos[i][0], infos[i][1], infos[i][2], &needed)) == NULL) continue; next = buf; while (next < buf + needed) { rtm = (struct rt_msghdr *)(void *)next; next += rtm->rtm_msglen; handle_rtmsg(rtm); } free(buf); } /* * Purge the address list of unused entries. These may happen for * interface aliases that are on the same subnet. We don't receive * routing socket messages for them. */ ifa = TAILQ_FIRST(&mibifa_list); while (ifa != NULL) { ifa1 = TAILQ_NEXT(ifa, link); if (!(ifa->flags & MIBIFA_FOUND)) destroy_ifa(ifa); ifa = ifa1; } rcv = TAILQ_FIRST(&mibrcvaddr_list); while (rcv != NULL) { rcv1 = TAILQ_NEXT(rcv, link); if (!(rcv->flags & (MIBRCVADDR_FOUND | MIBRCVADDR_BCAST | MIBRCVADDR_HW))) mib_rcvaddr_delete(rcv); rcv = rcv1; } } /* * Update arp table */ void mib_arp_update(void) { struct mibarp *at, *at1; size_t needed; u_char *buf, *next; struct rt_msghdr *rtm; if (in_update_arp) return; /* Aaargh */ in_update_arp = 1; TAILQ_FOREACH(at, &mibarp_list, link) at->flags &= ~MIBARP_FOUND; if ((buf = mib_fetch_rtab(AF_INET, NET_RT_FLAGS, RTF_LLINFO, &needed)) == NULL) { in_update_arp = 0; return; } next = buf; while (next < buf + needed) { rtm = (struct rt_msghdr *)(void *)next; next += rtm->rtm_msglen; handle_rtmsg(rtm); } free(buf); at = TAILQ_FIRST(&mibarp_list); while (at != NULL) { at1 = TAILQ_NEXT(at, link); if (!(at->flags & MIBARP_FOUND)) mib_arp_delete(at); at = at1; } mibarpticks = get_ticks(); update_arp = 0; in_update_arp = 0; } /* * Intput on the routing socket. */ static void route_input(int fd, void *udata __unused) { u_char buf[1024 * 16]; ssize_t n; struct rt_msghdr *rtm; if ((n = read(fd, buf, sizeof(buf))) == -1) err(1, "read(rt_socket)"); if (n == 0) errx(1, "EOF on rt_socket"); rtm = (struct rt_msghdr *)(void *)buf; if ((size_t)n != rtm->rtm_msglen) errx(1, "n=%zu, rtm_msglen=%u", (size_t)n, rtm->rtm_msglen); handle_rtmsg(rtm); } /* * execute and SIOCAIFADDR */ static int siocaifaddr(char *ifname, struct in_addr addr, struct in_addr mask, struct in_addr bcast) { struct ifaliasreq addreq; struct sockaddr_in *sa; memset(&addreq, 0, sizeof(addreq)); strncpy(addreq.ifra_name, ifname, sizeof(addreq.ifra_name)); sa = (struct sockaddr_in *)(void *)&addreq.ifra_addr; sa->sin_family = AF_INET; sa->sin_len = sizeof(*sa); sa->sin_addr = addr; sa = (struct sockaddr_in *)(void *)&addreq.ifra_mask; sa->sin_family = AF_INET; sa->sin_len = sizeof(*sa); sa->sin_addr = mask; sa = (struct sockaddr_in *)(void *)&addreq.ifra_broadaddr; sa->sin_family = AF_INET; sa->sin_len = sizeof(*sa); sa->sin_addr = bcast; return (ioctl(mib_netsock, SIOCAIFADDR, &addreq)); } /* * Exececute a SIOCDIFADDR */ static int siocdifaddr(const char *ifname, struct in_addr addr) { struct ifreq delreq; struct sockaddr_in *sa; memset(&delreq, 0, sizeof(delreq)); strncpy(delreq.ifr_name, ifname, sizeof(delreq.ifr_name)); sa = (struct sockaddr_in *)(void *)&delreq.ifr_addr; sa->sin_family = AF_INET; sa->sin_len = sizeof(*sa); sa->sin_addr = addr; return (ioctl(mib_netsock, SIOCDIFADDR, &delreq)); } /* * Verify an interface address without fetching the entire list */ static int verify_ifa(const char *name, struct mibifa *ifa) { struct ifreq req; struct sockaddr_in *sa; memset(&req, 0, sizeof(req)); strncpy(req.ifr_name, name, sizeof(req.ifr_name)); sa = (struct sockaddr_in *)(void *)&req.ifr_addr; sa->sin_family = AF_INET; sa->sin_len = sizeof(*sa); sa->sin_addr = ifa->inaddr; if (ioctl(mib_netsock, SIOCGIFADDR, &req) == -1) return (-1); if (ifa->inaddr.s_addr != sa->sin_addr.s_addr) { syslog(LOG_ERR, "%s: address mismatch", __func__); return (-1); } if (ioctl(mib_netsock, SIOCGIFNETMASK, &req) == -1) return (-1); if (ifa->inmask.s_addr != sa->sin_addr.s_addr) { syslog(LOG_ERR, "%s: netmask mismatch", __func__); return (-1); } return (0); } /* * Restore a deleted interface address. Don't wait for the routing socket * to update us. */ void mib_undestroy_ifa(struct mibifa *ifa) { struct mibif *ifp; if ((ifp = mib_find_if(ifa->ifindex)) == NULL) /* keep it destroyed */ return; if (siocaifaddr(ifp->name, ifa->inaddr, ifa->inmask, ifa->inbcast)) /* keep it destroyed */ return; ifa->flags &= ~MIBIFA_DESTROYED; } /* * Destroy an interface address */ int mib_destroy_ifa(struct mibifa *ifa) { struct mibif *ifp; if ((ifp = mib_find_if(ifa->ifindex)) == NULL) { /* ups. */ mib_iflist_bad = 1; return (-1); } if (siocdifaddr(ifp->name, ifa->inaddr)) { /* ups. */ syslog(LOG_ERR, "SIOCDIFADDR: %m"); mib_iflist_bad = 1; return (-1); } ifa->flags |= MIBIFA_DESTROYED; return (0); } /* * Rollback the modification of an address. Don't bother to wait for * the routing socket. */ void mib_unmodify_ifa(struct mibifa *ifa) { struct mibif *ifp; if ((ifp = mib_find_if(ifa->ifindex)) == NULL) { /* ups. */ mib_iflist_bad = 1; return; } if (siocaifaddr(ifp->name, ifa->inaddr, ifa->inmask, ifa->inbcast)) { /* ups. */ mib_iflist_bad = 1; return; } } /* * Modify an IFA. */ int mib_modify_ifa(struct mibifa *ifa) { struct mibif *ifp; if ((ifp = mib_find_if(ifa->ifindex)) == NULL) { /* ups. */ mib_iflist_bad = 1; return (-1); } if (siocaifaddr(ifp->name, ifa->inaddr, ifa->inmask, ifa->inbcast)) { /* ups. */ mib_iflist_bad = 1; return (-1); } if (verify_ifa(ifp->name, ifa)) { /* ups. */ mib_iflist_bad = 1; return (-1); } return (0); } /* * Destroy a freshly created interface address. Don't bother to wait for * the routing socket. */ void mib_uncreate_ifa(struct mibifa *ifa) { struct mibif *ifp; if ((ifp = mib_find_if(ifa->ifindex)) == NULL) { /* ups. */ mib_iflist_bad = 1; return; } if (siocdifaddr(ifp->name, ifa->inaddr)) { /* ups. */ mib_iflist_bad = 1; return; } destroy_ifa(ifa); } /* * Create a new ifa and verify it */ struct mibifa * mib_create_ifa(u_int ifindex, struct in_addr addr, struct in_addr mask, struct in_addr bcast) { struct mibif *ifp; struct mibifa *ifa; if ((ifp = mib_find_if(ifindex)) == NULL) return (NULL); if ((ifa = alloc_ifa(ifindex, addr)) == NULL) return (NULL); ifa->inmask = mask; ifa->inbcast = bcast; if (siocaifaddr(ifp->name, ifa->inaddr, ifa->inmask, ifa->inbcast)) { syslog(LOG_ERR, "%s: %m", __func__); destroy_ifa(ifa); return (NULL); } if (verify_ifa(ifp->name, ifa)) { destroy_ifa(ifa); return (NULL); } return (ifa); } /* * Get all cloning interfaces and make them dynamic. * Hah! Whe should probably do this on a periodic basis (XXX). */ static void get_cloners(void) { struct if_clonereq req; char *buf, *cp; int i; memset(&req, 0, sizeof(req)); if (ioctl(mib_netsock, SIOCIFGCLONERS, &req) == -1) { syslog(LOG_ERR, "get cloners: %m"); return; } if ((buf = malloc(req.ifcr_total * IFNAMSIZ)) == NULL) { syslog(LOG_ERR, "%m"); return; } req.ifcr_count = req.ifcr_total; req.ifcr_buffer = buf; if (ioctl(mib_netsock, SIOCIFGCLONERS, &req) == -1) { syslog(LOG_ERR, "get cloners: %m"); free(buf); return; } for (cp = buf, i = 0; i < req.ifcr_total; i++, cp += IFNAMSIZ) mib_if_set_dyn(cp); free(buf); } /* * Idle function */ static void mibII_idle(void) { struct mibifa *ifa; if (mib_iflist_bad) { TAILQ_FOREACH(ifa, &mibifa_list, link) ifa->flags &= ~MIBIFA_DESTROYED; /* assume, that all cloning interfaces are dynamic */ get_cloners(); mib_refresh_iflist(); update_ifa_info(); mib_arp_update(); mib_iflist_bad = 0; } if (update_arp) mib_arp_update(); } /* * Start the module */ static void mibII_start(void) { if ((route_fd = fd_select(route, route_input, NULL, module)) == NULL) { syslog(LOG_ERR, "fd_select(route): %m"); return; } mib_refresh_iflist(); update_ifa_info(); mib_arp_update(); mib_iftable_last_change = 0; mib_ifstack_last_change = 0; ifmib_reg = or_register(&oid_ifMIB, "The MIB module to describe generic objects for network interface" " sub-layers.", module); ipmib_reg = or_register(&oid_ipMIB, "The MIB module for managing IP and ICMP implementations, but " "excluding their management of IP routes.", module); tcpmib_reg = or_register(&oid_tcpMIB, "The MIB module for managing TCP implementations.", module); udpmib_reg = or_register(&oid_udpMIB, "The MIB module for managing UDP implementations.", module); ipForward_reg = or_register(&oid_ipForward, "The MIB module for the display of CIDR multipath IP Routes.", module); } /* * Initialize the module */ static int mibII_init(struct lmodule *mod, int argc __unused, char *argv[] __unused) { size_t len; module = mod; len = sizeof(clockinfo); if (sysctlbyname("kern.clockrate", &clockinfo, &len, NULL, 0) == -1) { syslog(LOG_ERR, "kern.clockrate: %m"); return (-1); } if (len != sizeof(clockinfo)) { syslog(LOG_ERR, "kern.clockrate: wrong size"); return (-1); } if ((route = socket(PF_ROUTE, SOCK_RAW, AF_UNSPEC)) == -1) { syslog(LOG_ERR, "PF_ROUTE: %m"); return (-1); } (void)shutdown(route, SHUT_WR); if ((mib_netsock = socket(PF_INET, SOCK_DGRAM, 0)) == -1) { syslog(LOG_ERR, "PF_INET: %m"); (void)close(route); return (-1); } (void)shutdown(mib_netsock, SHUT_RDWR); /* assume, that all cloning interfaces are dynamic */ get_cloners(); return (0); } static int mibII_fini(void) { if (route_fd != NULL) fd_deselect(route_fd); if (route != -1) (void)close(route); if (mib_netsock != -1) (void)close(mib_netsock); /* XXX free memory */ or_unregister(ipForward_reg); or_unregister(udpmib_reg); or_unregister(tcpmib_reg); or_unregister(ipmib_reg); or_unregister(ifmib_reg); return (0); } static void mibII_loading(const struct lmodule *mod, int loaded) { struct mibif *ifp; if (loaded == 1) return; TAILQ_FOREACH(ifp, &mibif_list, link) if (ifp->xnotify_mod == mod) { ifp->xnotify_mod = NULL; ifp->xnotify_data = NULL; ifp->xnotify = NULL; } mib_unregister_newif(mod); } const struct snmp_module config = { "This module implements the interface and ip groups.", mibII_init, mibII_fini, mibII_idle, /* idle */ NULL, /* dump */ NULL, /* config */ mibII_start, NULL, mibII_ctree, mibII_CTREE_SIZE, mibII_loading }; /* * Should have a list of these attached to each interface. */ void * mibif_notify(struct mibif *ifp, const struct lmodule *mod, mibif_notify_f func, void *data) { ifp->xnotify = func; ifp->xnotify_data = data; ifp->xnotify_mod = mod; return (ifp); } void mibif_unnotify(void *arg) { struct mibif *ifp = arg; ifp->xnotify = NULL; ifp->xnotify_data = NULL; ifp->xnotify_mod = NULL; }