/* $NetBSD: vif.c,v 1.6 1995/12/10 10:07:19 mycroft Exp $ */ /* * The mrouted program is covered by the license in the accompanying file * named "LICENSE". Use of the mrouted program represents acceptance of * the terms and conditions listed in that file. * * The mrouted program is COPYRIGHT 1989 by The Board of Trustees of * Leland Stanford Junior University. */ #include "defs.h" #include /* * Exported variables. */ struct uvif uvifs[MAXVIFS]; /* array of virtual interfaces */ vifi_t numvifs; /* number of vifs in use */ int vifs_down; /* 1=>some interfaces are down */ int phys_vif; /* An enabled vif */ int udp_socket; /* Since the honkin' kernel doesn't support */ /* ioctls on raw IP sockets, we need a UDP */ /* socket as well as our IGMP (raw) socket. */ /* How dumb. */ int vifs_with_neighbors; /* == 1 if I am a leaf */ typedef struct { vifi_t vifi; struct listaddr *g; int q_time; } cbk_t; /* * Forward declarations. */ static void start_vif(vifi_t vifi); static void start_vif2(vifi_t vifi); static void stop_vif(vifi_t vifi); static void age_old_hosts(void); static void send_probe_on_vif(struct uvif *v); static int info_version(char *p, int); static void DelVif(void *arg); static int SetTimer(int vifi, struct listaddr *g); static int DeleteTimer(int id); static void SendQuery(void *arg); static int SetQueryTimer(struct listaddr *g, vifi_t vifi, int to_expire, int q_time); /* * Initialize the virtual interfaces, but do not install * them in the kernel. Start routing on all vifs that are * not down or disabled. */ void init_vifs(void) { vifi_t vifi; struct uvif *v; int enabled_vifs, enabled_phyints; extern char *configfilename; numvifs = 0; vifs_with_neighbors = 0; vifs_down = FALSE; /* * Configure the vifs based on the interface configuration of the * the kernel and the contents of the configuration file. * (Open a UDP socket for ioctl use in the config procedures.) */ if ((udp_socket = socket(AF_INET, SOCK_DGRAM, 0)) < 0) logit(LOG_ERR, errno, "UDP socket"); logit(LOG_INFO,0,"Getting vifs from kernel interfaces"); config_vifs_from_kernel(); logit(LOG_INFO,0,"Getting vifs from %s",configfilename); config_vifs_from_file(); /* * Quit if there are fewer than two enabled vifs. */ enabled_vifs = 0; enabled_phyints = 0; phys_vif = -1; for (vifi = 0, v = uvifs; vifi < numvifs; ++vifi, ++v) { if (!(v->uv_flags & VIFF_DISABLED)) { ++enabled_vifs; if (!(v->uv_flags & VIFF_TUNNEL)) { if (phys_vif == -1) phys_vif = vifi; ++enabled_phyints; } } } if (enabled_vifs < 2) logit(LOG_ERR, 0, "can't forward: %s", enabled_vifs == 0 ? "no enabled vifs" : "only one enabled vif"); if (enabled_phyints == 0) logit(LOG_WARNING, 0, "no enabled interfaces, forwarding via tunnels only"); logit(LOG_INFO, 0, "Installing vifs in mrouted..."); for (vifi = 0, v = uvifs; vifi < numvifs; ++vifi, ++v) { if (!(v->uv_flags & VIFF_DISABLED)) { if (!(v->uv_flags & VIFF_DOWN)) { if (v->uv_flags & VIFF_TUNNEL) logit(LOG_INFO, 0, "vif #%d, tunnel %s -> %s", vifi, inet_fmt(v->uv_lcl_addr, s1), inet_fmt(v->uv_rmt_addr, s2)); else logit(LOG_INFO, 0, "vif #%d, phyint %s", vifi, inet_fmt(v->uv_lcl_addr, s1)); start_vif2(vifi); } else logit(LOG_INFO, 0, "%s is not yet up; vif #%u not in service", v->uv_name, vifi); } } } /* * Start routing on all virtual interfaces that are not down or * administratively disabled. */ void init_installvifs(void) { vifi_t vifi; struct uvif *v; logit(LOG_INFO, 0, "Installing vifs in kernel..."); for (vifi = 0, v = uvifs; vifi < numvifs; ++vifi, ++v) { if (!(v->uv_flags & VIFF_DISABLED)) { if (!(v->uv_flags & VIFF_DOWN)) { if (v->uv_flags & VIFF_TUNNEL) logit(LOG_INFO, 0, "vif #%d, tunnel %s -> %s", vifi, inet_fmt(v->uv_lcl_addr, s1), inet_fmt(v->uv_rmt_addr, s2)); else logit(LOG_INFO, 0, "vif #%d, phyint %s", vifi, inet_fmt(v->uv_lcl_addr, s1)); k_add_vif(vifi, &uvifs[vifi]); } else logit(LOG_INFO, 0, "%s is not yet up; vif #%u not in service", v->uv_name, vifi); } } } /* * See if any interfaces have changed from up state to down, or vice versa, * including any non-multicast-capable interfaces that are in use as local * tunnel end-points. Ignore interfaces that have been administratively * disabled. */ void check_vif_state(void) { vifi_t vifi; struct uvif *v; struct ifreq ifr; vifs_down = FALSE; for (vifi = 0, v = uvifs; vifi < numvifs; ++vifi, ++v) { if (v->uv_flags & VIFF_DISABLED) continue; strncpy(ifr.ifr_name, v->uv_name, IFNAMSIZ); if (ioctl(udp_socket, SIOCGIFFLAGS, (char *)&ifr) < 0) logit(LOG_ERR, errno, "ioctl SIOCGIFFLAGS for %s", ifr.ifr_name); if (v->uv_flags & VIFF_DOWN) { if (ifr.ifr_flags & IFF_UP) { v->uv_flags &= ~VIFF_DOWN; start_vif(vifi); logit(LOG_INFO, 0, "%s has come up; vif #%u now in service", v->uv_name, vifi); } else vifs_down = TRUE; } else { if (!(ifr.ifr_flags & IFF_UP)) { stop_vif(vifi); v->uv_flags |= VIFF_DOWN; logit(LOG_INFO, 0, "%s has gone down; vif #%u taken out of service", v->uv_name, vifi); vifs_down = TRUE; } } } } /* * Send a probe message on vif v */ static void send_probe_on_vif(struct uvif *v) { char *p; int datalen = 0; struct listaddr *nbr; int i; p = send_buf + MIN_IP_HEADER_LEN + IGMP_MINLEN; for (i = 0; i < 4; i++) *p++ = ((char *)&(dvmrp_genid))[i]; datalen += 4; /* * add the neighbor list on the interface to the message */ nbr = v->uv_neighbors; while (nbr) { for (i = 0; i < 4; i++) *p++ = ((char *)&nbr->al_addr)[i]; datalen +=4; nbr = nbr->al_next; } send_igmp(v->uv_lcl_addr, (v->uv_flags & VIFF_TUNNEL) ? v->uv_rmt_addr : dvmrp_group, IGMP_DVMRP, DVMRP_PROBE, htonl(MROUTED_LEVEL | ((v->uv_flags & VIFF_LEAF) ? 0 : LEAF_FLAGS)), datalen); } /* * Add a vifi to the kernel and start routing on it. */ static void start_vif(vifi_t vifi) { /* * Install the interface in the kernel's vif structure. */ k_add_vif(vifi, &uvifs[vifi]); start_vif2(vifi); } /* * Add a vifi to all the user-level data structures but don't add * it to the kernel yet. */ static void start_vif2(vifi_t vifi) { struct uvif *v; u_int32_t src; struct phaddr *p; v = &uvifs[vifi]; src = v->uv_lcl_addr; /* * Update the existing route entries to take into account the new vif. */ add_vif_to_routes(vifi); if (!(v->uv_flags & VIFF_TUNNEL)) { /* * Join the DVMRP multicast group on the interface. * (This is not strictly necessary, since the kernel promiscuously * receives IGMP packets addressed to ANY IP multicast group while * multicast routing is enabled. However, joining the group allows * this host to receive non-IGMP packets as well, such as 'pings'.) */ k_join(dvmrp_group, src); /* * Join the ALL-ROUTERS multicast group on the interface. * This allows mtrace requests to loop back if they are run * on the multicast router. */ k_join(allrtrs_group, src); /* * Install an entry in the routing table for the subnet to which * the interface is connected. */ start_route_updates(); update_route(v->uv_subnet, v->uv_subnetmask, 0, 0, vifi); for (p = v->uv_addrs; p; p = p->pa_next) { start_route_updates(); update_route(p->pa_subnet, p->pa_subnetmask, 0, 0, vifi); } /* * Until neighbors are discovered, assume responsibility for sending * periodic group membership queries to the subnet. Send the first * query. */ v->uv_flags |= VIFF_QUERIER; send_igmp(src, allhosts_group, IGMP_HOST_MEMBERSHIP_QUERY, (v->uv_flags & VIFF_IGMPV1) ? 0 : IGMP_MAX_HOST_REPORT_DELAY * IGMP_TIMER_SCALE, 0, 0); age_old_hosts(); } v->uv_leaf_timer = LEAF_CONFIRMATION_TIME; /* * Send a probe via the new vif to look for neighbors. */ send_probe_on_vif(v); } /* * Stop routing on the specified virtual interface. */ static void stop_vif(vifi_t vifi) { struct uvif *v; struct listaddr *a; struct phaddr *p; v = &uvifs[vifi]; if (!(v->uv_flags & VIFF_TUNNEL)) { /* * Depart from the DVMRP multicast group on the interface. */ k_leave(dvmrp_group, v->uv_lcl_addr); /* * Depart from the ALL-ROUTERS multicast group on the interface. */ k_leave(allrtrs_group, v->uv_lcl_addr); /* * Update the entry in the routing table for the subnet to which * the interface is connected, to take into account the interface * failure. */ start_route_updates(); update_route(v->uv_subnet, v->uv_subnetmask, UNREACHABLE, 0, vifi); for (p = v->uv_addrs; p; p = p->pa_next) { start_route_updates(); update_route(p->pa_subnet, p->pa_subnetmask, UNREACHABLE, 0, vifi); } /* * Discard all group addresses. (No need to tell kernel; * the k_del_vif() call, below, will clean up kernel state.) */ while (v->uv_groups != NULL) { a = v->uv_groups; v->uv_groups = a->al_next; free((char *)a); } v->uv_flags &= ~VIFF_QUERIER; } /* * Update the existing route entries to take into account the vif failure. */ delete_vif_from_routes(vifi); /* * Delete the interface from the kernel's vif structure. */ k_del_vif(vifi); /* * Discard all neighbor addresses. */ if (v->uv_neighbors) vifs_with_neighbors--; while (v->uv_neighbors != NULL) { a = v->uv_neighbors; v->uv_neighbors = a->al_next; free((char *)a); } } /* * stop routing on all vifs */ void stop_all_vifs(void) { vifi_t vifi; struct uvif *v; struct listaddr *a; struct vif_acl *acl; for (vifi = 0; vifi < numvifs; vifi++) { v = &uvifs[vifi]; while (v->uv_groups != NULL) { a = v->uv_groups; v->uv_groups = a->al_next; free((char *)a); } while (v->uv_neighbors != NULL) { a = v->uv_neighbors; v->uv_neighbors = a->al_next; free((char *)a); } while (v->uv_acl != NULL) { acl = v->uv_acl; v->uv_acl = acl->acl_next; free((char *)acl); } } } /* * Find the virtual interface from which an incoming packet arrived, * based on the packet's source and destination IP addresses. */ vifi_t find_vif(u_int32_t src, u_int32_t dst) { vifi_t vifi; struct uvif *v; struct phaddr *p; for (vifi = 0, v = uvifs; vifi < numvifs; ++vifi, ++v) { if (!(v->uv_flags & (VIFF_DOWN|VIFF_DISABLED))) { if (v->uv_flags & VIFF_TUNNEL) { if (src == v->uv_rmt_addr && dst == v->uv_lcl_addr) return(vifi); } else { if ((src & v->uv_subnetmask) == v->uv_subnet && ((v->uv_subnetmask == 0xffffffff) || (src != v->uv_subnetbcast))) return(vifi); for (p=v->uv_addrs; p; p=p->pa_next) { if ((src & p->pa_subnetmask) == p->pa_subnet && ((p->pa_subnetmask == 0xffffffff) || (src != p->pa_subnetbcast))) return(vifi); } } } } return (NO_VIF); } static void age_old_hosts(void) { vifi_t vifi; struct uvif *v; struct listaddr *g; /* * Decrement the old-hosts-present timer for each * active group on each vif. */ for (vifi = 0, v = uvifs; vifi < numvifs; vifi++, v++) for (g = v->uv_groups; g != NULL; g = g->al_next) if (g->al_old) g->al_old--; } /* * Send group membership queries to all subnets for which I am querier. */ void query_groups(void) { vifi_t vifi; struct uvif *v; for (vifi = 0, v = uvifs; vifi < numvifs; vifi++, v++) { if (v->uv_flags & VIFF_QUERIER) { send_igmp(v->uv_lcl_addr, allhosts_group, IGMP_HOST_MEMBERSHIP_QUERY, (v->uv_flags & VIFF_IGMPV1) ? 0 : IGMP_MAX_HOST_REPORT_DELAY * IGMP_TIMER_SCALE, 0, 0); } } age_old_hosts(); } /* * Process an incoming host membership query */ void accept_membership_query(u_int32_t src, u_int32_t dst, u_int32_t group, int tmo) { vifi_t vifi; struct uvif *v; if ((vifi = find_vif(src, dst)) == NO_VIF || (uvifs[vifi].uv_flags & VIFF_TUNNEL)) { logit(LOG_INFO, 0, "ignoring group membership query from non-adjacent host %s", inet_fmt(src, s1)); return; } v = &uvifs[vifi]; /* * If we consider ourselves the querier for this vif, but hear a * query from a router with a lower IP address, yield to them. * * This is done here as well as in the neighbor discovery in case * there is a querier that doesn't speak DVMRP. * * XXX If this neighbor doesn't speak DVMRP, then we need to create * some neighbor state for him so that we can time him out! */ if ((v->uv_flags & VIFF_QUERIER) && (ntohl(src) < ntohl(v->uv_lcl_addr))) { v->uv_flags &= ~VIFF_QUERIER; } } /* * Process an incoming group membership report. */ void accept_group_report(u_int32_t src, u_int32_t dst, u_int32_t group, int r_type) { vifi_t vifi; struct uvif *v; struct listaddr *g; if ((vifi = find_vif(src, dst)) == NO_VIF || (uvifs[vifi].uv_flags & VIFF_TUNNEL)) { logit(LOG_INFO, 0, "ignoring group membership report from non-adjacent host %s", inet_fmt(src, s1)); return; } v = &uvifs[vifi]; /* * Look for the group in our group list; if found, reset its timer. */ for (g = v->uv_groups; g != NULL; g = g->al_next) { if (group == g->al_addr) { if (r_type == IGMP_v1_HOST_MEMBERSHIP_REPORT) g->al_old = OLD_AGE_THRESHOLD; /** delete old timers, set a timer for expiration **/ g->al_timer = GROUP_EXPIRE_TIME; if (g->al_query) g->al_query = DeleteTimer(g->al_query); if (g->al_timerid) g->al_timerid = DeleteTimer(g->al_timerid); g->al_timerid = SetTimer(vifi, g); break; } } /* * If not found, add it to the list and update kernel cache. */ if (g == NULL) { g = (struct listaddr *)malloc(sizeof(struct listaddr)); if (g == NULL) logit(LOG_ERR, 0, "ran out of memory"); /* fatal */ g->al_addr = group; if (r_type == IGMP_v2_HOST_MEMBERSHIP_REPORT) g->al_old = 0; else g->al_old = OLD_AGE_THRESHOLD; /** set a timer for expiration **/ g->al_query = 0; g->al_timer = GROUP_EXPIRE_TIME; time(&g->al_ctime); g->al_timerid = SetTimer(vifi, g); g->al_next = v->uv_groups; v->uv_groups = g; update_lclgrp(vifi, group); } /* * Check if a graft is necessary for this group */ chkgrp_graft(vifi, group); } void accept_leave_message(u_int32_t src, u_int32_t dst, u_int32_t group) { vifi_t vifi; struct uvif *v; struct listaddr *g; if ((vifi = find_vif(src, dst)) == NO_VIF || (uvifs[vifi].uv_flags & VIFF_TUNNEL)) { logit(LOG_INFO, 0, "ignoring group leave report from non-adjacent host %s", inet_fmt(src, s1)); return; } v = &uvifs[vifi]; if (!(v->uv_flags & VIFF_QUERIER) || (v->uv_flags & VIFF_IGMPV1)) return; /* * Look for the group in our group list in order to set up a short-timeout * query. */ for (g = v->uv_groups; g != NULL; g = g->al_next) { if (group == g->al_addr) { logit(LOG_DEBUG, 0, "[vif.c, _accept_leave_message] %d %d \n", g->al_old, g->al_query); /* Ignore the leave message if there are old hosts present */ if (g->al_old) return; /* still waiting for a reply to a query, ignore the leave */ if (g->al_query) return; /** delete old timer set a timer for expiration **/ if (g->al_timerid) g->al_timerid = DeleteTimer(g->al_timerid); /** send a group specific querry **/ g->al_timer = LEAVE_EXPIRE_TIME; send_igmp(v->uv_lcl_addr, g->al_addr, IGMP_HOST_MEMBERSHIP_QUERY, LEAVE_EXPIRE_TIME / 3 * IGMP_TIMER_SCALE, g->al_addr, 0); g->al_query = SetQueryTimer(g, vifi, g->al_timer / 3, LEAVE_EXPIRE_TIME / 3 * IGMP_TIMER_SCALE); g->al_timerid = SetTimer(vifi, g); break; } } } /* * Send a periodic probe on all vifs. * Useful to determine one-way interfaces. * Detect neighbor loss faster. */ void probe_for_neighbors(void) { vifi_t vifi; struct uvif *v; for (vifi = 0, v = uvifs; vifi < numvifs; vifi++, v++) { if (!(v->uv_flags & (VIFF_DOWN|VIFF_DISABLED))) { send_probe_on_vif(v); } } } /* * Send a list of all of our neighbors to the requestor, `src'. */ void accept_neighbor_request(u_int32_t src, u_int32_t dst) { vifi_t vifi; struct uvif *v; u_char *p, *ncount; struct listaddr *la; int datalen; u_int32_t temp_addr, us, them = src; /* Determine which of our addresses to use as the source of our response * to this query. */ if (IN_MULTICAST(ntohl(dst))) { /* query sent to a multicast group */ int udp; /* find best interface to reply on */ struct sockaddr_in addr; int addrlen = sizeof(addr); memset(&addr, 0, sizeof addr); addr.sin_family = AF_INET; addr.sin_len = sizeof addr; addr.sin_addr.s_addr = dst; addr.sin_port = htons(2000); /* any port over 1024 will do... */ if ((udp = socket(AF_INET, SOCK_DGRAM, 0)) < 0 || connect(udp, (struct sockaddr *) &addr, sizeof(addr)) < 0 || getsockname(udp, (struct sockaddr *) &addr, &addrlen) < 0) { logit(LOG_WARNING, errno, "Determining local address"); close(udp); return; } close(udp); us = addr.sin_addr.s_addr; } else /* query sent to us alone */ us = dst; #define PUT_ADDR(a) temp_addr = ntohl(a); \ *p++ = temp_addr >> 24; \ *p++ = (temp_addr >> 16) & 0xFF; \ *p++ = (temp_addr >> 8) & 0xFF; \ *p++ = temp_addr & 0xFF; p = (u_char *) (send_buf + MIN_IP_HEADER_LEN + IGMP_MINLEN); datalen = 0; for (vifi = 0, v = uvifs; vifi < numvifs; vifi++, v++) { if (v->uv_flags & VIFF_DISABLED) continue; ncount = 0; for (la = v->uv_neighbors; la; la = la->al_next) { /* Make sure that there's room for this neighbor... */ if (datalen + (ncount == 0 ? 4 + 3 + 4 : 4) > MAX_DVMRP_DATA_LEN) { send_igmp(us, them, IGMP_DVMRP, DVMRP_NEIGHBORS, htonl(MROUTED_LEVEL), datalen); p = (u_char *) (send_buf + MIN_IP_HEADER_LEN + IGMP_MINLEN); datalen = 0; ncount = 0; } /* Put out the header for this neighbor list... */ if (ncount == 0) { PUT_ADDR(v->uv_lcl_addr); *p++ = v->uv_metric; *p++ = v->uv_threshold; ncount = p; *p++ = 0; datalen += 4 + 3; } PUT_ADDR(la->al_addr); datalen += 4; (*ncount)++; } } if (datalen != 0) send_igmp(us, them, IGMP_DVMRP, DVMRP_NEIGHBORS, htonl(MROUTED_LEVEL), datalen); } /* * Send a list of all of our neighbors to the requestor, `src'. */ void accept_neighbor_request2(u_int32_t src, u_int32_t dst) { vifi_t vifi; struct uvif *v; u_char *p, *ncount; struct listaddr *la; int datalen; u_int32_t us, them = src; /* Determine which of our addresses to use as the source of our response * to this query. */ if (IN_MULTICAST(ntohl(dst))) { /* query sent to a multicast group */ int udp; /* find best interface to reply on */ struct sockaddr_in addr; int addrlen = sizeof(addr); memset(&addr, 0, sizeof addr); addr.sin_family = AF_INET; addr.sin_len = sizeof addr; addr.sin_addr.s_addr = dst; addr.sin_port = htons(2000); /* any port over 1024 will do... */ if ((udp = socket(AF_INET, SOCK_DGRAM, 0)) < 0 || connect(udp, (struct sockaddr *) &addr, sizeof(addr)) < 0 || getsockname(udp, (struct sockaddr *) &addr, &addrlen) < 0) { logit(LOG_WARNING, errno, "Determining local address"); close(udp); return; } close(udp); us = addr.sin_addr.s_addr; } else /* query sent to us alone */ us = dst; p = (u_char *) (send_buf + MIN_IP_HEADER_LEN + IGMP_MINLEN); datalen = 0; for (vifi = 0, v = uvifs; vifi < numvifs; vifi++, v++) { u_short vflags = v->uv_flags; u_char rflags = 0; if (vflags & VIFF_TUNNEL) rflags |= DVMRP_NF_TUNNEL; if (vflags & VIFF_SRCRT) rflags |= DVMRP_NF_SRCRT; if (vflags & VIFF_DOWN) rflags |= DVMRP_NF_DOWN; if (vflags & VIFF_DISABLED) rflags |= DVMRP_NF_DISABLED; if (vflags & VIFF_QUERIER) rflags |= DVMRP_NF_QUERIER; if (vflags & VIFF_LEAF) rflags |= DVMRP_NF_LEAF; ncount = 0; la = v->uv_neighbors; if (la == NULL) { /* * include down & disabled interfaces and interfaces on * leaf nets. */ if (rflags & DVMRP_NF_TUNNEL) rflags |= DVMRP_NF_DOWN; if (datalen > MAX_DVMRP_DATA_LEN - 12) { send_igmp(us, them, IGMP_DVMRP, DVMRP_NEIGHBORS2, htonl(MROUTED_LEVEL), datalen); p = (u_char *) (send_buf + MIN_IP_HEADER_LEN + IGMP_MINLEN); datalen = 0; } *(u_int*)p = v->uv_lcl_addr; p += 4; *p++ = v->uv_metric; *p++ = v->uv_threshold; *p++ = rflags; *p++ = 1; *(u_int*)p = v->uv_rmt_addr; p += 4; datalen += 12; } else { for ( ; la; la = la->al_next) { /* Make sure that there's room for this neighbor... */ if (datalen + (ncount == 0 ? 4+4+4 : 4) > MAX_DVMRP_DATA_LEN) { send_igmp(us, them, IGMP_DVMRP, DVMRP_NEIGHBORS2, htonl(MROUTED_LEVEL), datalen); p = (u_char *) (send_buf + MIN_IP_HEADER_LEN + IGMP_MINLEN); datalen = 0; ncount = 0; } /* Put out the header for this neighbor list... */ if (ncount == 0) { *(u_int*)p = v->uv_lcl_addr; p += 4; *p++ = v->uv_metric; *p++ = v->uv_threshold; *p++ = rflags; ncount = p; *p++ = 0; datalen += 4 + 4; } *(u_int*)p = la->al_addr; p += 4; datalen += 4; (*ncount)++; } } } if (datalen != 0) send_igmp(us, them, IGMP_DVMRP, DVMRP_NEIGHBORS2, htonl(MROUTED_LEVEL), datalen); } void accept_info_request(u_int32_t src, u_int32_t dst, u_char *p, int datalen) { u_char *q; int len; int outlen = 0; q = (u_char *) (send_buf + MIN_IP_HEADER_LEN + IGMP_MINLEN); /* To be general, this must deal properly with breaking up over-sized * packets. That implies passing a length to each function, and * allowing each function to request to be called again. Right now, * we're only implementing the one thing we are positive will fit into * a single packet, so we wimp out. */ while (datalen > 0) { len = 0; switch (*p) { case DVMRP_INFO_VERSION: len = info_version(q, (u_char *)send_buf + RECV_BUF_SIZE - q); break; case DVMRP_INFO_NEIGHBORS: default: logit(LOG_INFO, 0, "ignoring unknown info type %d", *p); break; } *(q+1) = len++; outlen += len * 4; q += len * 4; len = (*(p+1) + 1) * 4; p += len; datalen -= len; } if (outlen != 0) send_igmp(INADDR_ANY, src, IGMP_DVMRP, DVMRP_INFO_REPLY, htonl(MROUTED_LEVEL), outlen); } /* * Information response -- return version string */ static int info_version(char *p, int len) { extern char versionstring[]; if (len < 5) return (0); *p++ = DVMRP_INFO_VERSION; p++; /* skip over length */ *p++ = 0; /* zero out */ *p++ = 0; /* reserved fields */ strlcpy(p, versionstring, len - 4); len = strlen(p); return ((len + 3) / 4); } /* * Process an incoming neighbor-list message. */ void accept_neighbors(u_int32_t src, u_int32_t dst, u_char *p, int datalen, u_int32_t level) { logit(LOG_INFO, 0, "ignoring spurious DVMRP neighbor list from %s to %s", inet_fmt(src, s1), inet_fmt(dst, s2)); } /* * Process an incoming neighbor-list message. */ void accept_neighbors2(u_int32_t src, u_int32_t dst, u_char *p, int datalen, u_int32_t level) { logit(LOG_INFO, 0, "ignoring spurious DVMRP neighbor list2 from %s to %s", inet_fmt(src, s1), inet_fmt(dst, s2)); } /* * Process an incoming info reply message. */ void accept_info_reply(u_int32_t src, u_int32_t dst, u_char *p, int datalen) { logit(LOG_INFO, 0, "ignoring spurious DVMRP info reply from %s to %s", inet_fmt(src, s1), inet_fmt(dst, s2)); } /* * Update the neighbor entry for neighbor 'addr' on vif 'vifi'. * 'msgtype' is the type of DVMRP message received from the neighbor. * Return TRUE if 'addr' is a valid neighbor, FALSE otherwise. */ int update_neighbor(vifi_t vifi, u_int32_t addr, int msgtype, char *p, int datalen, u_int32_t level) { struct uvif *v; struct listaddr *n; u_int32_t genid = 0; u_int32_t router; u_int32_t send_tables = 0; int do_reset = FALSE; int nflags; v = &uvifs[vifi]; nflags = (level >> 16) & 0xff; /* * Confirm that 'addr' is a valid neighbor address on vif 'vifi'. * IT IS ASSUMED that this was preceded by a call to find_vif(), which * checks that 'addr' is either a valid remote tunnel endpoint or a * non-broadcast address belonging to a directly-connected subnet. * Therefore, here we check only that 'addr' is not our own address * (due to an impostor or erroneous loopback) or an address of the form * {subnet,0} ("the unknown host"). These checks are not performed in * find_vif() because those types of address are acceptable for some * types of IGMP message (such as group membership reports). */ if (!(v->uv_flags & VIFF_TUNNEL) && (addr == v->uv_lcl_addr || addr == v->uv_subnet )) { logit(LOG_WARNING, 0, "received DVMRP message from 'the unknown host' or self: %s", inet_fmt(addr, s1)); return (FALSE); } /* * Look for addr in list of neighbors. */ for (n = v->uv_neighbors; n != NULL; n = n->al_next) { if (addr == n->al_addr) { break; } } /* * Found it. Reset its timer, and check for a version change */ if (n) { n->al_timer = 0; /* * update the neighbors version and protocol number * if changed => router went down and came up, * so take action immediately. */ if ((n->al_pv != (level & 0xff)) || (n->al_mv != ((level >> 8) & 0xff))) { do_reset = TRUE; logit(LOG_DEBUG, 0, "version change neighbor %s [old:%d.%d, new:%d.%d]", inet_fmt(addr, s1), n->al_pv, n->al_mv, level&0xff, (level >> 8) & 0xff); n->al_pv = level & 0xff; n->al_mv = (level >> 8) & 0xff; } } else { /* * If not found, add it to the list. If the neighbor has a lower * IP address than me, yield querier duties to it. */ logit(LOG_DEBUG, 0, "New neighbor %s on vif %d v%d.%d nf 0x%02x", inet_fmt(addr, s1), vifi, level & 0xff, (level >> 8) & 0xff, (level >> 16) & 0xff); n = (struct listaddr *)malloc(sizeof(struct listaddr)); if (n == NULL) logit(LOG_ERR, 0, "ran out of memory"); /* fatal */ n->al_addr = addr; n->al_pv = level & 0xff; n->al_mv = (level >> 8) & 0xff; n->al_genid = 0; time(&n->al_ctime); n->al_timer = 0; n->al_next = v->uv_neighbors; /* * If we thought that we had no neighbors on this vif, send a route * report to the vif. If this is just a new neighbor on the same * vif, send the route report just to the new neighbor. */ if (v->uv_neighbors == NULL) { send_tables = (v->uv_flags & VIFF_TUNNEL) ? addr : dvmrp_group; vifs_with_neighbors++; } else { send_tables = addr; } v->uv_neighbors = n; if (!(v->uv_flags & VIFF_TUNNEL) && ntohl(addr) < ntohl(v->uv_lcl_addr)) v->uv_flags &= ~VIFF_QUERIER; } /* * Check if the router gen-ids are the same. * Need to reset the prune state of the router if not. * Also check for one-way interfaces by seeing if we are in our * neighbor's list of known routers. */ if (msgtype == DVMRP_PROBE) { /* Check genid neighbor flag. Also check version number; 3.3 and * 3.4 didn't set this flag. */ if ((((level >> 16) & 0xff) & NF_GENID) || (((level & 0xff) == 3) && (((level >> 8) & 0xff) > 2))) { int i; if (datalen < 4) { logit(LOG_WARNING, 0, "received truncated probe message from %s (len %d)", inet_fmt(addr, s1), datalen); return (FALSE); } for (i = 0; i < 4; i++) ((char *)&genid)[i] = *p++; datalen -= 4; if (n->al_genid == 0) n->al_genid = genid; else if (n->al_genid != genid) { logit(LOG_DEBUG, 0, "new genid neigbor %s on vif %d [old:%x, new:%x]", inet_fmt(addr, s1), vifi, n->al_genid, genid); n->al_genid = genid; do_reset = TRUE; } /* * loop through router list and check for one-way ifs. */ v->uv_flags |= VIFF_ONEWAY; while (datalen > 0) { if (datalen < 4) { logit(LOG_WARNING, 0, "received truncated probe message from %s (len %d)", inet_fmt(addr, s1), datalen); return (FALSE); } for (i = 0; i < 4; i++) ((char *)&router)[i] = *p++; datalen -= 4; if (router == v->uv_lcl_addr) { v->uv_flags &= ~VIFF_ONEWAY; break; } } } } if (n->al_flags != nflags) { n->al_flags = nflags; if (n->al_flags & NF_LEAF) { /*XXX If we have non-leaf neighbors then we know we shouldn't * mark this vif as a leaf. For now we just count on other * probes and/or reports resetting the timer. */ if (!v->uv_leaf_timer) v->uv_leaf_timer = LEAF_CONFIRMATION_TIME; } else { /* If we get a leaf to non-leaf transition, we *must* update * the routing table. */ if (v->uv_flags & VIFF_LEAF && send_tables == 0) send_tables = addr; v->uv_flags &= ~VIFF_LEAF; v->uv_leaf_timer = 0; } } if (do_reset) { reset_neighbor_state(vifi, addr); if (!send_tables) send_tables = addr; } if (send_tables) report(ALL_ROUTES, vifi, send_tables); return (TRUE); } /* * On every timer interrupt, advance the timer in each neighbor and * group entry on every vif. */ void age_vifs(void) { vifi_t vifi; struct uvif *v; struct listaddr *a, *prev_a, *n; u_int32_t addr; for (vifi = 0, v = uvifs; vifi < numvifs; ++vifi, ++v ) { if (v->uv_leaf_timer && (v->uv_leaf_timer -= TIMER_INTERVAL == 0)) { v->uv_flags |= VIFF_LEAF; } for (prev_a = (struct listaddr *)&(v->uv_neighbors), a = v->uv_neighbors; a != NULL; prev_a = a, a = a->al_next) { if ((a->al_timer += TIMER_INTERVAL) < NEIGHBOR_EXPIRE_TIME) continue; /* * Neighbor has expired; delete it from the neighbor list, * delete it from the 'dominants' and 'subordinates arrays of * any route entries and assume querier duties unless there is * another neighbor with a lower IP address than mine. */ addr = a->al_addr; prev_a->al_next = a->al_next; free((char *)a); a = prev_a; delete_neighbor_from_routes(addr, vifi); if (v->uv_neighbors == NULL) vifs_with_neighbors--; v->uv_leaf_timer = LEAF_CONFIRMATION_TIME; if (!(v->uv_flags & VIFF_TUNNEL)) { v->uv_flags |= VIFF_QUERIER; for (n = v->uv_neighbors; n != NULL; n = n->al_next) { if (ntohl(n->al_addr) < ntohl(v->uv_lcl_addr)) { v->uv_flags &= ~VIFF_QUERIER; } if (!(n->al_flags & NF_LEAF)) { v->uv_leaf_timer = 0; } } } } } } /* * Returns the neighbor info struct for a given neighbor */ struct listaddr * neighbor_info(vifi_t vifi, u_int32_t addr) { struct listaddr *u; for (u = uvifs[vifi].uv_neighbors; u; u = u->al_next) if (u->al_addr == addr) return u; return NULL; } /* * Print the contents of the uvifs array on file 'fp'. */ void dump_vifs(FILE *fp) { vifi_t vifi; struct uvif *v; struct listaddr *a; struct phaddr *p; struct sioc_vif_req v_req; fprintf(fp, "vifs_with_neighbors = %d\n", vifs_with_neighbors); if (vifs_with_neighbors == 1) fprintf(fp,"[This host is a leaf]\n\n"); fprintf(fp, "\nVirtual Interface Table\n%s", "Vif Name Local-Address "); fprintf(fp, "M Thr Rate Flags\n"); for (vifi = 0, v = uvifs; vifi < numvifs; vifi++, v++) { fprintf(fp, "%2u %6s %-15s %6s: %-18s %2u %3u %5u ", vifi, v->uv_name, inet_fmt(v->uv_lcl_addr, s1), (v->uv_flags & VIFF_TUNNEL) ? "tunnel": "subnet", (v->uv_flags & VIFF_TUNNEL) ? inet_fmt(v->uv_rmt_addr, s2) : inet_fmts(v->uv_subnet, v->uv_subnetmask, s3), v->uv_metric, v->uv_threshold, v->uv_rate_limit); if (v->uv_flags & VIFF_ONEWAY) fprintf(fp, " one-way"); if (v->uv_flags & VIFF_DOWN) fprintf(fp, " down"); if (v->uv_flags & VIFF_DISABLED) fprintf(fp, " disabled"); if (v->uv_flags & VIFF_QUERIER) fprintf(fp, " querier"); if (v->uv_flags & VIFF_SRCRT) fprintf(fp, " src-rt"); if (v->uv_flags & VIFF_LEAF) fprintf(fp, " leaf"); if (v->uv_flags & VIFF_IGMPV1) fprintf(fp, " IGMPv1"); fprintf(fp, "\n"); if (v->uv_addrs != NULL) { fprintf(fp, " alternate subnets: %s\n", inet_fmts(v->uv_addrs->pa_subnet, v->uv_addrs->pa_subnetmask, s1)); for (p = v->uv_addrs->pa_next; p; p = p->pa_next) { fprintf(fp, " %s\n", inet_fmts(p->pa_subnet, p->pa_subnetmask, s1)); } } if (v->uv_neighbors != NULL) { fprintf(fp, " peers: %s (%d.%d) (0x%x)\n", inet_fmt(v->uv_neighbors->al_addr, s1), v->uv_neighbors->al_pv, v->uv_neighbors->al_mv, v->uv_neighbors->al_flags); for (a = v->uv_neighbors->al_next; a != NULL; a = a->al_next) { fprintf(fp, " %s (%d.%d) (0x%x)\n", inet_fmt(a->al_addr, s1), a->al_pv, a->al_mv, a->al_flags); } } if (v->uv_groups != NULL) { fprintf(fp, " groups: %-15s\n", inet_fmt(v->uv_groups->al_addr, s1)); for (a = v->uv_groups->al_next; a != NULL; a = a->al_next) { fprintf(fp, " %-15s\n", inet_fmt(a->al_addr, s1)); } } if (v->uv_acl != NULL) { struct vif_acl *acl; fprintf(fp, " boundaries: %-18s\n", inet_fmts(v->uv_acl->acl_addr, v->uv_acl->acl_mask, s1)); for (acl = v->uv_acl->acl_next; acl != NULL; acl = acl->acl_next) { fprintf(fp, " : %-18s\n", inet_fmts(acl->acl_addr, acl->acl_mask, s1)); } } v_req.vifi = vifi; if (ioctl(udp_socket, SIOCGETVIFCNT, (char *)&v_req) < 0) { logit(LOG_WARNING, 0, "SIOCGETVIFCNT fails"); } else { fprintf(fp, " pkts in : %ld\n", v_req.icount); fprintf(fp, " pkts out: %ld\n", v_req.ocount); } fprintf(fp, "\n"); } fprintf(fp, "\n"); } /* * Time out record of a group membership on a vif */ static void DelVif(void *arg) { cbk_t *cbk = (cbk_t *)arg; vifi_t vifi = cbk->vifi; struct uvif *v = &uvifs[vifi]; struct listaddr *a, **anp, *g = cbk->g; /* * Group has expired * delete all kernel cache entries with this group */ if (g->al_query) DeleteTimer(g->al_query); delete_lclgrp(vifi, g->al_addr); anp = &(v->uv_groups); while ((a = *anp) != NULL) { if (a == g) { *anp = a->al_next; free((char *)a); } else { anp = &a->al_next; } } free(cbk); } /* * Set a timer to delete the record of a group membership on a vif. */ static int SetTimer(int vifi, struct listaddr *g) { cbk_t *cbk; cbk = (cbk_t *) malloc(sizeof(cbk_t)); cbk->g = g; cbk->vifi = vifi; return timer_setTimer(g->al_timer, (cfunc_t)DelVif, (void *)cbk); } /* * Delete a timer that was set above. */ static int DeleteTimer(int id) { timer_clearTimer(id); return 0; } /* * Send a group-specific query. */ static void SendQuery(void *arg) { cbk_t *cbk = (cbk_t *)arg; struct uvif *v = &uvifs[cbk->vifi]; send_igmp(v->uv_lcl_addr, cbk->g->al_addr, IGMP_HOST_MEMBERSHIP_QUERY, cbk->q_time, cbk->g->al_addr, 0); cbk->g->al_query = 0; free(cbk); } /* * Set a timer to send a group-specific query. */ static int SetQueryTimer(struct listaddr *g, vifi_t vifi, int to_expire, int q_time) { cbk_t *cbk; cbk = (cbk_t *) malloc(sizeof(cbk_t)); cbk->g = g; cbk->q_time = q_time; cbk->vifi = vifi; return timer_setTimer(to_expire, (cfunc_t)SendQuery, (void *)cbk); }