/* Kernel communication using routing socket. * Copyright (C) 1999 Kunihiro Ishiguro * * This file is part of GNU Zebra. * * GNU Zebra is free software; you can redistribute it and/or modify it * under the terms of the GNU General Public License as published by the * Free Software Foundation; either version 2, or (at your option) any * later version. * * GNU Zebra is distributed in the hope that it will be useful, but * WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU * General Public License for more details. * * You should have received a copy of the GNU General Public License * along with GNU Zebra; see the file COPYING. If not, write to the Free * Software Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA * 02111-1307, USA. */ #include #include "if.h" #include "prefix.h" #include "sockunion.h" #include "connected.h" #include "memory.h" #include "ioctl.h" #include "log.h" #include "str.h" #include "table.h" #include "rib.h" #include "privs.h" #include "zebra/interface.h" #include "zebra/zserv.h" #include "zebra/debug.h" #include "zebra/kernel_socket.h" extern struct zebra_privs_t zserv_privs; extern struct zebra_t zebrad; /* * Given a sockaddr length, round it up to include pad bytes following * it. Assumes the kernel pads to sizeof(long). * * XXX: why is ROUNDUP(0) sizeof(long)? 0 is an illegal sockaddr * length anyway (< sizeof (struct sockaddr)), so this shouldn't * matter. */ #define ROUNDUP(a) \ ((a) > 0 ? (1 + (((a) - 1) | (sizeof(long) - 1))) : sizeof(long)) /* * Given a pointer (sockaddr or void *), return the number of bytes * taken up by the sockaddr and any padding needed for alignment. */ #if defined(HAVE_STRUCT_SOCKADDR_SA_LEN) #define SAROUNDUP(X) ROUNDUP(((struct sockaddr *)(X))->sa_len) #elif defined(HAVE_IPV6) /* * One would hope all fixed-size structure definitions are aligned, * but round them up nonetheless. */ #define SAROUNDUP(X) \ (((struct sockaddr *)(X))->sa_family == AF_INET ? \ ROUNDUP(sizeof(struct sockaddr_in)):\ (((struct sockaddr *)(X))->sa_family == AF_INET6 ? \ ROUNDUP(sizeof(struct sockaddr_in6)) : \ (((struct sockaddr *)(X))->sa_family == AF_LINK ? \ ROUNDUP(sizeof(struct sockaddr_dl)) : sizeof(struct sockaddr)))) #else /* HAVE_IPV6 */ #define SAROUNDUP(X) \ (((struct sockaddr *)(X))->sa_family == AF_INET ? \ ROUNDUP(sizeof(struct sockaddr_in)):\ (((struct sockaddr *)(X))->sa_family == AF_LINK ? \ ROUNDUP(sizeof(struct sockaddr_dl)) : sizeof(struct sockaddr))) #endif /* HAVE_STRUCT_SOCKADDR_SA_LEN */ /* We use an additional pointer in following, pdest, rather than (DEST) * directly, because gcc will warn if the macro is expanded and DEST is NULL, * complaining that memcpy is being passed a NULL value, despite the fact * the if (NULL) makes it impossible. */ #define RTA_ADDR_GET(DEST, RTA, RTMADDRS, PNT) \ if ((RTMADDRS) & (RTA)) \ { \ void *pdest = (DEST); \ int len = SAROUNDUP ((PNT)); \ if ( ((DEST) != NULL) && \ af_check (((struct sockaddr *)(PNT))->sa_family)) \ memcpy (pdest, (PNT), len); \ (PNT) += len; \ } #define RTA_ATTR_GET(DEST, RTA, RTMADDRS, PNT) \ if ((RTMADDRS) & (RTA)) \ { \ void *pdest = (DEST); \ int len = SAROUNDUP ((PNT)); \ if ((DEST) != NULL) \ memcpy (pdest, (PNT), len); \ (PNT) += len; \ } #define RTA_NAME_GET(DEST, RTA, RTMADDRS, PNT, LEN) \ if ((RTMADDRS) & (RTA)) \ { \ u_char *pdest = (u_char *) (DEST); \ int len = SAROUNDUP ((PNT)); \ struct sockaddr_dl *sdl = (struct sockaddr_dl *)(PNT); \ if (IS_ZEBRA_DEBUG_KERNEL) \ zlog_debug ("%s: RTA_SDL_GET nlen %d, alen %d", \ __func__, sdl->sdl_nlen, sdl->sdl_alen); \ if ( ((DEST) != NULL) && (sdl->sdl_family == AF_LINK) \ && (sdl->sdl_nlen < IFNAMSIZ) && (sdl->sdl_nlen <= len) ) \ { \ memcpy (pdest, sdl->sdl_data, sdl->sdl_nlen); \ pdest[sdl->sdl_nlen] = '\0'; \ (LEN) = sdl->sdl_nlen; \ } \ (PNT) += len; \ } \ else \ { \ (LEN) = 0; \ } /* Routing socket message types. */ struct message rtm_type_str[] = { {RTM_ADD, "RTM_ADD"}, {RTM_DELETE, "RTM_DELETE"}, {RTM_CHANGE, "RTM_CHANGE"}, {RTM_GET, "RTM_GET"}, {RTM_LOSING, "RTM_LOSING"}, {RTM_REDIRECT, "RTM_REDIRECT"}, {RTM_MISS, "RTM_MISS"}, {RTM_LOCK, "RTM_LOCK"}, #ifdef OLDADD {RTM_OLDADD, "RTM_OLDADD"}, #endif /* RTM_OLDADD */ #ifdef RTM_OLDDEL {RTM_OLDDEL, "RTM_OLDDEL"}, #endif /* RTM_OLDDEL */ {RTM_RESOLVE, "RTM_RESOLVE"}, {RTM_NEWADDR, "RTM_NEWADDR"}, {RTM_DELADDR, "RTM_DELADDR"}, {RTM_IFINFO, "RTM_IFINFO"}, #ifdef RTM_OIFINFO {RTM_OIFINFO, "RTM_OIFINFO"}, #endif /* RTM_OIFINFO */ #ifdef RTM_NEWMADDR {RTM_NEWMADDR, "RTM_NEWMADDR"}, #endif /* RTM_NEWMADDR */ #ifdef RTM_DELMADDR {RTM_DELMADDR, "RTM_DELMADDR"}, #endif /* RTM_DELMADDR */ #ifdef RTM_IFANNOUNCE {RTM_IFANNOUNCE, "RTM_IFANNOUNCE"}, #endif /* RTM_IFANNOUNCE */ {0, NULL} }; int rtm_type_str_max = sizeof (rtm_type_str) / sizeof (struct message) - 1; struct message rtm_flag_str[] = { {RTF_UP, "UP"}, {RTF_GATEWAY, "GATEWAY"}, {RTF_HOST, "HOST"}, {RTF_REJECT, "REJECT"}, {RTF_DYNAMIC, "DYNAMIC"}, {RTF_MODIFIED, "MODIFIED"}, {RTF_DONE, "DONE"}, #ifdef RTF_MASK {RTF_MASK, "MASK"}, #endif /* RTF_MASK */ {RTF_CLONING, "CLONING"}, {RTF_XRESOLVE, "XRESOLVE"}, {RTF_LLINFO, "LLINFO"}, {RTF_STATIC, "STATIC"}, {RTF_BLACKHOLE, "BLACKHOLE"}, #ifdef RTF_PRIVATE {RTF_PRIVATE, "PRIVATE"}, #endif /* RTF_PRIVATE */ {RTF_PROTO1, "PROTO1"}, {RTF_PROTO2, "PROTO2"}, #ifdef RTF_PRCLONING {RTF_PRCLONING, "PRCLONING"}, #endif /* RTF_PRCLONING */ #ifdef RTF_WASCLONED {RTF_WASCLONED, "WASCLONED"}, #endif /* RTF_WASCLONED */ #ifdef RTF_PROTO3 {RTF_PROTO3, "PROTO3"}, #endif /* RTF_PROTO3 */ #ifdef RTF_PINNED {RTF_PINNED, "PINNED"}, #endif /* RTF_PINNED */ #ifdef RTF_LOCAL {RTF_LOCAL, "LOCAL"}, #endif /* RTF_LOCAL */ #ifdef RTF_BROADCAST {RTF_BROADCAST, "BROADCAST"}, #endif /* RTF_BROADCAST */ #ifdef RTF_MULTICAST {RTF_MULTICAST, "MULTICAST"}, #endif /* RTF_MULTICAST */ #ifdef RTF_MULTIRT {RTF_MULTIRT, "MULTIRT"}, #endif /* RTF_MULTIRT */ #ifdef RTF_SETSRC {RTF_SETSRC, "SETSRC"}, #endif /* RTF_SETSRC */ {0, NULL} }; /* Kernel routing update socket. */ int routing_sock = -1; /* Yes I'm checking ugly routing socket behavior. */ /* #define DEBUG */ /* Supported address family check. */ static int inline af_check (int family) { if (family == AF_INET) return 1; #ifdef HAVE_IPV6 if (family == AF_INET6) return 1; #endif /* HAVE_IPV6 */ return 0; } /* Dump routing table flag for debug purpose. */ static void rtm_flag_dump (int flag) { struct message *mes; static char buf[BUFSIZ]; buf[0] = '\0'; for (mes = rtm_flag_str; mes->key != 0; mes++) { if (mes->key & flag) { strlcat (buf, mes->str, BUFSIZ); strlcat (buf, " ", BUFSIZ); } } zlog_debug ("Kernel: %s", buf); } #ifdef RTM_IFANNOUNCE /* Interface adding function */ static int ifan_read (struct if_announcemsghdr *ifan) { struct interface *ifp; ifp = if_lookup_by_index (ifan->ifan_index); if (ifp) assert ( (ifp->ifindex == ifan->ifan_index) || (ifp->ifindex == IFINDEX_INTERNAL) ); if ( (ifp == NULL) || ((ifp->ifindex == IFINDEX_INTERNAL) && (ifan->ifan_what == IFAN_ARRIVAL)) ) { if (IS_ZEBRA_DEBUG_KERNEL) zlog_debug ("%s: creating interface for ifindex %d, name %s", __func__, ifan->ifan_index, ifan->ifan_name); /* Create Interface */ ifp = if_get_by_name_len(ifan->ifan_name, strnlen(ifan->ifan_name, sizeof(ifan->ifan_name))); ifp->ifindex = ifan->ifan_index; if_add_update (ifp); } else if (ifp != NULL && ifan->ifan_what == IFAN_DEPARTURE) if_delete_update (ifp); if_get_flags (ifp); if_get_mtu (ifp); if_get_metric (ifp); if (IS_ZEBRA_DEBUG_KERNEL) zlog_debug ("%s: interface %s index %d", __func__, ifan->ifan_name, ifan->ifan_index); return 0; } #endif /* RTM_IFANNOUNCE */ /* * Handle struct if_msghdr obtained from reading routing socket or * sysctl (from interface_list). There may or may not be sockaddrs * present after the header. */ int ifm_read (struct if_msghdr *ifm) { struct interface *ifp = NULL; char ifname[IFNAMSIZ]; short ifnlen = 0; caddr_t *cp; /* terminate ifname at head (for strnlen) and tail (for safety) */ ifname[IFNAMSIZ - 1] = '\0'; /* paranoia: sanity check structure */ if (ifm->ifm_msglen < sizeof(struct if_msghdr)) { zlog_err ("ifm_read: ifm->ifm_msglen %d too short\n", ifm->ifm_msglen); return -1; } /* * Check for a sockaddr_dl following the message. First, point to * where a socakddr might be if one follows the message. */ cp = (void *)(ifm + 1); #ifdef SUNOS_5 /* * XXX This behavior should be narrowed to only the kernel versions * for which the structures returned do not match the headers. * * if_msghdr_t on 64 bit kernels in Solaris 9 and earlier versions * is 12 bytes larger than the 32 bit version. */ if (((struct sockaddr *) cp)->sa_family == AF_UNSPEC) cp = cp + 12; #endif RTA_ADDR_GET (NULL, RTA_DST, ifm->ifm_addrs, cp); RTA_ADDR_GET (NULL, RTA_GATEWAY, ifm->ifm_addrs, cp); RTA_ATTR_GET (NULL, RTA_NETMASK, ifm->ifm_addrs, cp); RTA_ADDR_GET (NULL, RTA_GENMASK, ifm->ifm_addrs, cp); RTA_NAME_GET (ifname, RTA_IFP, ifm->ifm_addrs, cp, ifnlen); RTA_ADDR_GET (NULL, RTA_IFA, ifm->ifm_addrs, cp); RTA_ADDR_GET (NULL, RTA_AUTHOR, ifm->ifm_addrs, cp); RTA_ADDR_GET (NULL, RTA_BRD, ifm->ifm_addrs, cp); if (IS_ZEBRA_DEBUG_KERNEL) zlog_debug ("%s: sdl ifname %s", __func__, (ifnlen ? ifname : "(nil)")); /* * Look up on ifindex first, because ifindices are the primary handle for * interfaces across the user/kernel boundary, for most systems. (Some * messages, such as up/down status changes on NetBSD, do not include a * sockaddr_dl). */ if ( (ifp = if_lookup_by_index (ifm->ifm_index)) != NULL ) { /* we have an ifp, verify that the name matches as some systems, * eg Solaris, have a 1:many association of ifindex:ifname * if they dont match, we dont have the correct ifp and should * set it back to NULL to let next check do lookup by name */ if (ifnlen && (strncmp (ifp->name, ifname, IFNAMSIZ) != 0) ) { if (IS_ZEBRA_DEBUG_KERNEL) zlog_debug ("%s: ifp name %s doesnt match sdl name %s", __func__, ifp->name, ifname); ifp = NULL; } } /* * If we dont have an ifp, try looking up by name. Particularly as some * systems (Solaris) have a 1:many mapping of ifindex:ifname - the ifname * is therefore our unique handle to that interface. * * Interfaces specified in the configuration file for which the ifindex * has not been determined will have ifindex == IFINDEX_INTERNAL, and such * interfaces are found by this search, and then their ifindex values can * be filled in. */ if ( (ifp == NULL) && ifnlen) ifp = if_lookup_by_name (ifname); /* * If ifp still does not exist or has an invalid index (IFINDEX_INTERNAL), * create or fill in an interface. */ if ((ifp == NULL) || (ifp->ifindex == IFINDEX_INTERNAL)) { /* * To create or fill in an interface, a sockaddr_dl (via * RTA_IFP) is required. */ if (!ifnlen) { zlog_warn ("Interface index %d (new) missing ifname\n", ifm->ifm_index); return -1; } #ifndef RTM_IFANNOUNCE /* Down->Down interface should be ignored here. * See further comment below. */ if (!CHECK_FLAG (ifm->ifm_flags, IFF_UP)) return 0; #endif /* !RTM_IFANNOUNCE */ if (ifp == NULL) { /* Interface that zebra was not previously aware of, so create. */ ifp = if_create (ifname, ifnlen); if (IS_ZEBRA_DEBUG_KERNEL) zlog_debug ("%s: creating ifp for ifindex %d", __func__, ifm->ifm_index); } if (IS_ZEBRA_DEBUG_KERNEL) zlog_debug ("%s: updated/created ifp, ifname %s, ifindex %d", __func__, ifp->name, ifp->ifindex); /* * Fill in newly created interface structure, or larval * structure with ifindex IFINDEX_INTERNAL. */ ifp->ifindex = ifm->ifm_index; if_flags_update (ifp, ifm->ifm_flags); #if defined(__bsdi__) if_kvm_get_mtu (ifp); #else if_get_mtu (ifp); #endif /* __bsdi__ */ if_get_metric (ifp); if_add_update (ifp); } else /* * Interface structure exists. Adjust stored flags from * notification. If interface has up->down or down->up * transition, call state change routines (to adjust routes, * notify routing daemons, etc.). (Other flag changes are stored * but apparently do not trigger action.) */ { if (ifp->ifindex != ifm->ifm_index) { zlog_warn ("%s: index mismatch, ifname %s, ifp index %d, " "ifm index %d", __func__, ifp->name, ifp->ifindex, ifm->ifm_index); return -1; } /* update flags and handle operative->inoperative transition, if any */ if_flags_update (ifp, ifm->ifm_flags); #ifndef RTM_IFANNOUNCE if (!if_is_up (ifp)) { /* No RTM_IFANNOUNCE on this platform, so we can never * distinguish between ~IFF_UP and delete. We must presume * it has been deleted. * Eg, Solaris will not notify us of unplumb. * * XXX: Fixme - this should be runtime detected * So that a binary compiled on a system with IFANNOUNCE * will still behave correctly if run on a platform without */ if_delete_update (ifp); } #endif /* RTM_IFANNOUNCE */ if (if_is_up (ifp)) { #if defined(__bsdi__) if_kvm_get_mtu (ifp); #else if_get_mtu (ifp); #endif /* __bsdi__ */ if_get_metric (ifp); } } #ifdef HAVE_NET_RT_IFLIST ifp->stats = ifm->ifm_data; #endif /* HAVE_NET_RT_IFLIST */ if (IS_ZEBRA_DEBUG_KERNEL) zlog_debug ("%s: interface %s index %d", __func__, ifp->name, ifp->ifindex); return 0; } /* Address read from struct ifa_msghdr. */ static void ifam_read_mesg (struct ifa_msghdr *ifm, union sockunion *addr, union sockunion *mask, union sockunion *brd, char *ifname, short *ifnlen) { caddr_t pnt, end; union sockunion dst; union sockunion gateway; pnt = (caddr_t)(ifm + 1); end = ((caddr_t)ifm) + ifm->ifam_msglen; /* Be sure structure is cleared */ memset (mask, 0, sizeof (union sockunion)); memset (addr, 0, sizeof (union sockunion)); memset (brd, 0, sizeof (union sockunion)); memset (&dst, 0, sizeof (union sockunion)); memset (&gateway, 0, sizeof (union sockunion)); /* We fetch each socket variable into sockunion. */ RTA_ADDR_GET (&dst, RTA_DST, ifm->ifam_addrs, pnt); RTA_ADDR_GET (&gateway, RTA_GATEWAY, ifm->ifam_addrs, pnt); RTA_ATTR_GET (mask, RTA_NETMASK, ifm->ifam_addrs, pnt); RTA_ADDR_GET (NULL, RTA_GENMASK, ifm->ifam_addrs, pnt); RTA_NAME_GET (ifname, RTA_IFP, ifm->ifam_addrs, pnt, *ifnlen); RTA_ADDR_GET (addr, RTA_IFA, ifm->ifam_addrs, pnt); RTA_ADDR_GET (NULL, RTA_AUTHOR, ifm->ifam_addrs, pnt); RTA_ADDR_GET (brd, RTA_BRD, ifm->ifam_addrs, pnt); if (IS_ZEBRA_DEBUG_KERNEL) { switch (sockunion_family(addr)) { case AF_INET: { char buf[4][INET_ADDRSTRLEN]; zlog_debug ("%s: ifindex %d, ifname %s, ifam_addrs 0x%x, " "ifam_flags 0x%x, addr %s/%d broad %s dst %s " "gateway %s", __func__, ifm->ifam_index, (ifnlen ? ifname : "(nil)"), ifm->ifam_addrs, ifm->ifam_flags, inet_ntop(AF_INET,&addr->sin.sin_addr, buf[0],sizeof(buf[0])), ip_masklen(mask->sin.sin_addr), inet_ntop(AF_INET,&brd->sin.sin_addr, buf[1],sizeof(buf[1])), inet_ntop(AF_INET,&dst.sin.sin_addr, buf[2],sizeof(buf[2])), inet_ntop(AF_INET,&gateway.sin.sin_addr, buf[3],sizeof(buf[3]))); } break; #ifdef HAVE_IPV6 case AF_INET6: { char buf[4][INET6_ADDRSTRLEN]; zlog_debug ("%s: ifindex %d, ifname %s, ifam_addrs 0x%x, " "ifam_flags 0x%x, addr %s/%d broad %s dst %s " "gateway %s", __func__, ifm->ifam_index, (ifnlen ? ifname : "(nil)"), ifm->ifam_addrs, ifm->ifam_flags, inet_ntop(AF_INET6,&addr->sin6.sin6_addr, buf[0],sizeof(buf[0])), ip6_masklen(mask->sin6.sin6_addr), inet_ntop(AF_INET6,&brd->sin6.sin6_addr, buf[1],sizeof(buf[1])), inet_ntop(AF_INET6,&dst.sin6.sin6_addr, buf[2],sizeof(buf[2])), inet_ntop(AF_INET6,&gateway.sin6.sin6_addr, buf[3],sizeof(buf[3]))); } break; #endif /* HAVE_IPV6 */ default: zlog_debug ("%s: ifindex %d, ifname %s, ifam_addrs 0x%x", __func__, ifm->ifam_index, (ifnlen ? ifname : "(nil)"), ifm->ifam_addrs); break; } } /* Assert read up end point matches to end point */ if (pnt != end) zlog_warn ("ifam_read() does't read all socket data"); } /* Interface's address information get. */ int ifam_read (struct ifa_msghdr *ifam) { struct interface *ifp = NULL; union sockunion addr, mask, brd; char ifname[INTERFACE_NAMSIZ]; short ifnlen = 0; char isalias = 0; int flags = 0; ifname[0] = ifname[INTERFACE_NAMSIZ - 1] = '\0'; /* Allocate and read address information. */ ifam_read_mesg (ifam, &addr, &mask, &brd, ifname, &ifnlen); if ((ifp = if_lookup_by_index(ifam->ifam_index)) == NULL) { zlog_warn ("%s: no interface for ifname %s, index %d", __func__, ifname, ifam->ifam_index); return -1; } if (ifnlen && strncmp (ifp->name, ifname, INTERFACE_NAMSIZ)) isalias = 1; /* N.B. The info in ifa_msghdr does not tell us whether the RTA_BRD field contains a broadcast address or a peer address, so we are forced to rely upon the interface type. */ if (if_is_pointopoint(ifp)) SET_FLAG(flags, ZEBRA_IFA_PEER); #if 0 /* it might seem cute to grab the interface metric here, however * we're processing an address update message, and so some systems * (e.g. FBSD) dont bother to fill in ifam_metric. Disabled, but left * in deliberately, as comment. */ ifp->metric = ifam->ifam_metric; #endif /* Add connected address. */ switch (sockunion_family (&addr)) { case AF_INET: if (ifam->ifam_type == RTM_NEWADDR) connected_add_ipv4 (ifp, flags, &addr.sin.sin_addr, ip_masklen (mask.sin.sin_addr), &brd.sin.sin_addr, (isalias ? ifname : NULL)); else connected_delete_ipv4 (ifp, flags, &addr.sin.sin_addr, ip_masklen (mask.sin.sin_addr), &brd.sin.sin_addr); break; #ifdef HAVE_IPV6 case AF_INET6: /* Unset interface index from link-local address when IPv6 stack is KAME. */ if (IN6_IS_ADDR_LINKLOCAL (&addr.sin6.sin6_addr)) SET_IN6_LINKLOCAL_IFINDEX (addr.sin6.sin6_addr, 0); if (ifam->ifam_type == RTM_NEWADDR) connected_add_ipv6 (ifp, flags, &addr.sin6.sin6_addr, ip6_masklen (mask.sin6.sin6_addr), &brd.sin6.sin6_addr, (isalias ? ifname : NULL)); else connected_delete_ipv6 (ifp, &addr.sin6.sin6_addr, ip6_masklen (mask.sin6.sin6_addr), &brd.sin6.sin6_addr); break; #endif /* HAVE_IPV6 */ default: /* Unsupported family silently ignore... */ break; } /* Check interface flag for implicit up of the interface. */ if_refresh (ifp); #ifdef SUNOS_5 /* In addition to lacking IFANNOUNCE, on SUNOS IFF_UP is strange. * See comments for SUNOS_5 in interface.c::if_flags_mangle. * * Here we take care of case where the real IFF_UP was previously * unset (as kept in struct zebra_if.primary_state) and the mangled * IFF_UP (ie IFF_UP set || listcount(connected) has now transitioned * to unset due to the lost non-primary address having DELADDR'd. * * we must delete the interface, because in between here and next * event for this interface-name the administrator could unplumb * and replumb the interface. */ if (!if_is_up (ifp)) if_delete_update (ifp); #endif /* SUNOS_5 */ return 0; } /* Interface function for reading kernel routing table information. */ static int rtm_read_mesg (struct rt_msghdr *rtm, union sockunion *dest, union sockunion *mask, union sockunion *gate, char *ifname, short *ifnlen) { caddr_t pnt, end; /* Pnt points out socket data start point. */ pnt = (caddr_t)(rtm + 1); end = ((caddr_t)rtm) + rtm->rtm_msglen; /* rt_msghdr version check. */ if (rtm->rtm_version != RTM_VERSION) zlog (NULL, LOG_WARNING, "Routing message version different %d should be %d." "This may cause problem\n", rtm->rtm_version, RTM_VERSION); /* Be sure structure is cleared */ memset (dest, 0, sizeof (union sockunion)); memset (gate, 0, sizeof (union sockunion)); memset (mask, 0, sizeof (union sockunion)); /* We fetch each socket variable into sockunion. */ RTA_ADDR_GET (dest, RTA_DST, rtm->rtm_addrs, pnt); RTA_ADDR_GET (gate, RTA_GATEWAY, rtm->rtm_addrs, pnt); RTA_ATTR_GET (mask, RTA_NETMASK, rtm->rtm_addrs, pnt); RTA_ADDR_GET (NULL, RTA_GENMASK, rtm->rtm_addrs, pnt); RTA_NAME_GET (ifname, RTA_IFP, rtm->rtm_addrs, pnt, *ifnlen); RTA_ADDR_GET (NULL, RTA_IFA, rtm->rtm_addrs, pnt); RTA_ADDR_GET (NULL, RTA_AUTHOR, rtm->rtm_addrs, pnt); RTA_ADDR_GET (NULL, RTA_BRD, rtm->rtm_addrs, pnt); /* If there is netmask information set it's family same as destination family*/ if (rtm->rtm_addrs & RTA_NETMASK) mask->sa.sa_family = dest->sa.sa_family; /* Assert read up to the end of pointer. */ if (pnt != end) zlog (NULL, LOG_WARNING, "rtm_read() does't read all socket data."); return rtm->rtm_flags; } void rtm_read (struct rt_msghdr *rtm) { int flags; u_char zebra_flags; union sockunion dest, mask, gate; char ifname[INTERFACE_NAMSIZ + 1]; short ifnlen = 0; zebra_flags = 0; /* Read destination and netmask and gateway from rtm message structure. */ flags = rtm_read_mesg (rtm, &dest, &mask, &gate, ifname, &ifnlen); if (!(flags & RTF_DONE)) return; if (IS_ZEBRA_DEBUG_KERNEL) zlog_debug ("%s: got rtm of type %d (%s)", __func__, rtm->rtm_type, LOOKUP (rtm_type_str, rtm->rtm_type)); #ifdef RTF_CLONED /*bsdi, netbsd 1.6*/ if (flags & RTF_CLONED) return; #endif #ifdef RTF_WASCLONED /*freebsd*/ if (flags & RTF_WASCLONED) return; #endif if ((rtm->rtm_type == RTM_ADD) && ! (flags & RTF_UP)) return; /* This is connected route. */ if (! (flags & RTF_GATEWAY)) return; if (flags & RTF_PROTO1) SET_FLAG (zebra_flags, ZEBRA_FLAG_SELFROUTE); /* This is persistent route. */ if (flags & RTF_STATIC) SET_FLAG (zebra_flags, ZEBRA_FLAG_STATIC); /* This is a reject or blackhole route */ if (flags & RTF_REJECT) SET_FLAG (zebra_flags, ZEBRA_FLAG_REJECT); if (flags & RTF_BLACKHOLE) SET_FLAG (zebra_flags, ZEBRA_FLAG_BLACKHOLE); if (dest.sa.sa_family == AF_INET) { struct prefix_ipv4 p; p.family = AF_INET; p.prefix = dest.sin.sin_addr; if (flags & RTF_HOST) p.prefixlen = IPV4_MAX_PREFIXLEN; else p.prefixlen = ip_masklen (mask.sin.sin_addr); /* Catch self originated messages and match them against our current RIB. * At the same time, ignore unconfirmed messages, they should be tracked * by rtm_write() and kernel_rtm_ipv4(). */ if (rtm->rtm_type != RTM_GET && (rtm->rtm_pid == pid || rtm->rtm_pid == old_pid)) { char buf[INET_ADDRSTRLEN], gate_buf[INET_ADDRSTRLEN]; int ret; if (! IS_ZEBRA_DEBUG_RIB) return; ret = rib_lookup_ipv4_route (&p, &gate); inet_ntop (AF_INET, &p.prefix, buf, INET_ADDRSTRLEN); switch (rtm->rtm_type) { case RTM_ADD: case RTM_GET: case RTM_CHANGE: /* The kernel notifies us about a new route in FIB created by us. Do we have a correspondent entry in our RIB? */ switch (ret) { case ZEBRA_RIB_NOTFOUND: zlog_debug ("%s: %s %s/%d: desync: RR isn't yet in RIB, while already in FIB", __func__, LOOKUP (rtm_type_str, rtm->rtm_type), buf, p.prefixlen); break; case ZEBRA_RIB_FOUND_CONNECTED: case ZEBRA_RIB_FOUND_NOGATE: inet_ntop (AF_INET, &gate.sin.sin_addr, gate_buf, INET_ADDRSTRLEN); zlog_debug ("%s: %s %s/%d: desync: RR is in RIB, but gate differs (ours is %s)", __func__, LOOKUP (rtm_type_str, rtm->rtm_type), buf, p.prefixlen, gate_buf); break; case ZEBRA_RIB_FOUND_EXACT: /* RIB RR == FIB RR */ zlog_debug ("%s: %s %s/%d: done Ok", __func__, LOOKUP (rtm_type_str, rtm->rtm_type), buf, p.prefixlen); rib_lookup_and_dump (&p); return; break; } break; case RTM_DELETE: /* The kernel notifies us about a route deleted by us. Do we still have it in the RIB? Do we have anything instead? */ switch (ret) { case ZEBRA_RIB_FOUND_EXACT: zlog_debug ("%s: %s %s/%d: desync: RR is still in RIB, while already not in FIB", __func__, LOOKUP (rtm_type_str, rtm->rtm_type), buf, p.prefixlen); rib_lookup_and_dump (&p); break; case ZEBRA_RIB_FOUND_CONNECTED: case ZEBRA_RIB_FOUND_NOGATE: zlog_debug ("%s: %s %s/%d: desync: RR is still in RIB, plus gate differs", __func__, LOOKUP (rtm_type_str, rtm->rtm_type), buf, p.prefixlen); rib_lookup_and_dump (&p); break; case ZEBRA_RIB_NOTFOUND: /* RIB RR == FIB RR */ zlog_debug ("%s: %s %s/%d: done Ok", __func__, LOOKUP (rtm_type_str, rtm->rtm_type), buf, p.prefixlen); rib_lookup_and_dump (&p); return; break; } break; default: zlog_debug ("%s: %s/%d: warning: loopback RTM of type %s received", __func__, buf, p.prefixlen, LOOKUP (rtm_type_str, rtm->rtm_type)); } return; } /* Change, delete the old prefix, we have no further information * to specify the route really */ if (rtm->rtm_type == RTM_CHANGE) rib_delete_ipv4 (ZEBRA_ROUTE_KERNEL, zebra_flags, &p, NULL, 0, 0); if (rtm->rtm_type == RTM_GET || rtm->rtm_type == RTM_ADD || rtm->rtm_type == RTM_CHANGE) rib_add_ipv4 (ZEBRA_ROUTE_KERNEL, zebra_flags, &p, &gate.sin.sin_addr, NULL, 0, 0, 0, 0); else rib_delete_ipv4 (ZEBRA_ROUTE_KERNEL, zebra_flags, &p, &gate.sin.sin_addr, 0, 0); } #ifdef HAVE_IPV6 if (dest.sa.sa_family == AF_INET6) { struct prefix_ipv6 p; unsigned int ifindex = 0; p.family = AF_INET6; p.prefix = dest.sin6.sin6_addr; if (flags & RTF_HOST) p.prefixlen = IPV6_MAX_PREFIXLEN; else p.prefixlen = ip6_masklen (mask.sin6.sin6_addr); #ifdef KAME if (IN6_IS_ADDR_LINKLOCAL (&gate.sin6.sin6_addr)) { ifindex = IN6_LINKLOCAL_IFINDEX (gate.sin6.sin6_addr); SET_IN6_LINKLOCAL_IFINDEX (gate.sin6.sin6_addr, 0); } #endif /* KAME */ /* CHANGE: delete the old prefix, we have no further information * to specify the route really */ if (rtm->rtm_type == RTM_CHANGE) rib_delete_ipv6 (ZEBRA_ROUTE_KERNEL, zebra_flags, &p, NULL, 0, 0); if (rtm->rtm_type == RTM_GET || rtm->rtm_type == RTM_ADD || rtm->rtm_type == RTM_CHANGE) rib_add_ipv6 (ZEBRA_ROUTE_KERNEL, zebra_flags, &p, &gate.sin6.sin6_addr, ifindex, 0, 0, 0); else rib_delete_ipv6 (ZEBRA_ROUTE_KERNEL, zebra_flags, &p, &gate.sin6.sin6_addr, ifindex, 0); } #endif /* HAVE_IPV6 */ } /* Interface function for the kernel routing table updates. Support * for RTM_CHANGE will be needed. * Exported only for rt_socket.c */ int rtm_write (int message, union sockunion *dest, union sockunion *mask, union sockunion *gate, unsigned int index, int zebra_flags, int metric) { int ret; caddr_t pnt; struct interface *ifp; /* Sequencial number of routing message. */ static int msg_seq = 0; /* Struct of rt_msghdr and buffer for storing socket's data. */ struct { struct rt_msghdr rtm; char buf[512]; } msg; if (routing_sock < 0) return ZEBRA_ERR_EPERM; /* Clear and set rt_msghdr values */ memset (&msg, 0, sizeof (struct rt_msghdr)); msg.rtm.rtm_version = RTM_VERSION; msg.rtm.rtm_type = message; msg.rtm.rtm_seq = msg_seq++; msg.rtm.rtm_addrs = RTA_DST; msg.rtm.rtm_addrs |= RTA_GATEWAY; msg.rtm.rtm_flags = RTF_UP; msg.rtm.rtm_index = index; if (metric != 0) { msg.rtm.rtm_rmx.rmx_hopcount = metric; msg.rtm.rtm_inits |= RTV_HOPCOUNT; } ifp = if_lookup_by_index (index); if (gate && message == RTM_ADD) msg.rtm.rtm_flags |= RTF_GATEWAY; if (! gate && message == RTM_ADD && ifp && (ifp->flags & IFF_POINTOPOINT) == 0) msg.rtm.rtm_flags |= RTF_CLONING; /* If no protocol specific gateway is specified, use link address for gateway. */ if (! gate) { if (!ifp) { char dest_buf[INET_ADDRSTRLEN] = "NULL", mask_buf[INET_ADDRSTRLEN] = "255.255.255.255"; if (dest) inet_ntop (AF_INET, &dest->sin.sin_addr, dest_buf, INET_ADDRSTRLEN); if (mask) inet_ntop (AF_INET, &mask->sin.sin_addr, mask_buf, INET_ADDRSTRLEN); zlog_warn ("%s: %s/%s: gate == NULL and no gateway found for ifindex %d", __func__, dest_buf, mask_buf, index); return -1; } gate = (union sockunion *) & ifp->sdl; } if (mask) msg.rtm.rtm_addrs |= RTA_NETMASK; else if (message == RTM_ADD) msg.rtm.rtm_flags |= RTF_HOST; /* Tagging route with flags */ msg.rtm.rtm_flags |= (RTF_PROTO1); /* Additional flags. */ if (zebra_flags & ZEBRA_FLAG_BLACKHOLE) msg.rtm.rtm_flags |= RTF_BLACKHOLE; if (zebra_flags & ZEBRA_FLAG_REJECT) msg.rtm.rtm_flags |= RTF_REJECT; #ifdef HAVE_STRUCT_SOCKADDR_IN_SIN_LEN #define SOCKADDRSET(X,R) \ if (msg.rtm.rtm_addrs & (R)) \ { \ int len = ROUNDUP ((X)->sa.sa_len); \ memcpy (pnt, (caddr_t)(X), len); \ pnt += len; \ } #else #define SOCKADDRSET(X,R) \ if (msg.rtm.rtm_addrs & (R)) \ { \ int len = SAROUNDUP (X); \ memcpy (pnt, (caddr_t)(X), len); \ pnt += len; \ } #endif /* HAVE_STRUCT_SOCKADDR_IN_SIN_LEN */ pnt = (caddr_t) msg.buf; /* Write each socket data into rtm message buffer */ SOCKADDRSET (dest, RTA_DST); SOCKADDRSET (gate, RTA_GATEWAY); SOCKADDRSET (mask, RTA_NETMASK); msg.rtm.rtm_msglen = pnt - (caddr_t) &msg; ret = write (routing_sock, &msg, msg.rtm.rtm_msglen); if (ret != msg.rtm.rtm_msglen) { if (errno == EEXIST) return ZEBRA_ERR_RTEXIST; if (errno == ENETUNREACH) return ZEBRA_ERR_RTUNREACH; if (errno == ESRCH) return ZEBRA_ERR_RTNOEXIST; zlog_warn ("%s: write : %s (%d)", __func__, safe_strerror (errno), errno); return ZEBRA_ERR_KERNEL; } return ZEBRA_ERR_NOERROR; } #include "thread.h" #include "zebra/zserv.h" /* For debug purpose. */ static void rtmsg_debug (struct rt_msghdr *rtm) { zlog_debug ("Kernel: Len: %d Type: %s", rtm->rtm_msglen, LOOKUP (rtm_type_str, rtm->rtm_type)); rtm_flag_dump (rtm->rtm_flags); zlog_debug ("Kernel: message seq %d", rtm->rtm_seq); zlog_debug ("Kernel: pid %d, rtm_addrs 0x%x", rtm->rtm_pid, rtm->rtm_addrs); } /* This is pretty gross, better suggestions welcome -- mhandler */ #ifndef RTAX_MAX #ifdef RTA_NUMBITS #define RTAX_MAX RTA_NUMBITS #else #define RTAX_MAX 8 #endif /* RTA_NUMBITS */ #endif /* RTAX_MAX */ /* Kernel routing table and interface updates via routing socket. */ static int kernel_read (struct thread *thread) { int sock; int nbytes; struct rt_msghdr *rtm; /* * This must be big enough for any message the kernel might send. * Rather than determining how many sockaddrs of what size might be * in each particular message, just use RTAX_MAX of sockaddr_storage * for each. Note that the sockaddrs must be after each message * definition, or rather after whichever happens to be the largest, * since the buffer needs to be big enough for a message and the * sockaddrs together. */ union { /* Routing information. */ struct { struct rt_msghdr rtm; struct sockaddr_storage addr[RTAX_MAX]; } r; /* Interface information. */ struct { struct if_msghdr ifm; struct sockaddr_storage addr[RTAX_MAX]; } im; /* Interface address information. */ struct { struct ifa_msghdr ifa; struct sockaddr_storage addr[RTAX_MAX]; } ia; #ifdef RTM_IFANNOUNCE /* Interface arrival/departure */ struct { struct if_announcemsghdr ifan; struct sockaddr_storage addr[RTAX_MAX]; } ian; #endif /* RTM_IFANNOUNCE */ } buf; /* Fetch routing socket. */ sock = THREAD_FD (thread); nbytes= read (sock, &buf, sizeof buf); if (nbytes <= 0) { if (nbytes < 0 && errno != EWOULDBLOCK && errno != EAGAIN) zlog_warn ("routing socket error: %s", safe_strerror (errno)); return 0; } thread_add_read (zebrad.master, kernel_read, NULL, sock); if (IS_ZEBRA_DEBUG_KERNEL) rtmsg_debug (&buf.r.rtm); rtm = &buf.r.rtm; /* * Ensure that we didn't drop any data, so that processing routines * can assume they have the whole message. */ if (rtm->rtm_msglen != nbytes) { zlog_warn ("kernel_read: rtm->rtm_msglen %d, nbytes %d, type %d\n", rtm->rtm_msglen, nbytes, rtm->rtm_type); return -1; } switch (rtm->rtm_type) { case RTM_ADD: case RTM_DELETE: case RTM_CHANGE: rtm_read (rtm); break; case RTM_IFINFO: ifm_read (&buf.im.ifm); break; case RTM_NEWADDR: case RTM_DELADDR: ifam_read (&buf.ia.ifa); break; #ifdef RTM_IFANNOUNCE case RTM_IFANNOUNCE: ifan_read (&buf.ian.ifan); break; #endif /* RTM_IFANNOUNCE */ default: if (IS_ZEBRA_DEBUG_KERNEL) zlog_debug("Unprocessed RTM_type: %d", rtm->rtm_type); break; } return 0; } /* Make routing socket. */ static void routing_socket (void) { if ( zserv_privs.change (ZPRIVS_RAISE) ) zlog_err ("routing_socket: Can't raise privileges"); routing_sock = socket (AF_ROUTE, SOCK_RAW, 0); if (routing_sock < 0) { if ( zserv_privs.change (ZPRIVS_LOWER) ) zlog_err ("routing_socket: Can't lower privileges"); zlog_warn ("Can't init kernel routing socket"); return; } /* XXX: Socket should be NONBLOCK, however as we currently * discard failed writes, this will lead to inconsistencies. * For now, socket must be blocking. */ /*if (fcntl (routing_sock, F_SETFL, O_NONBLOCK) < 0) zlog_warn ("Can't set O_NONBLOCK to routing socket");*/ if ( zserv_privs.change (ZPRIVS_LOWER) ) zlog_err ("routing_socket: Can't lower privileges"); /* kernel_read needs rewrite. */ thread_add_read (zebrad.master, kernel_read, NULL, routing_sock); } /* Exported interface function. This function simply calls routing_socket (). */ void kernel_init (void) { routing_socket (); }