/* $OpenBSD: config.c,v 1.26 2008/04/23 10:17:50 pyr Exp $ */ /* $KAME: config.c,v 1.62 2002/05/29 10:13:10 itojun Exp $ */ /* * Copyright (C) 1998 WIDE Project. * All rights reserved. * * Redistribution and use in source and binary forms, with or without * modification, are permitted provided that the following conditions * are met: * 1. Redistributions of source code must retain the above copyright * notice, this list of conditions and the following disclaimer. * 2. Redistributions in binary form must reproduce the above copyright * notice, this list of conditions and the following disclaimer in the * documentation and/or other materials provided with the distribution. * 3. Neither the name of the project nor the names of its contributors * may be used to endorse or promote products derived from this software * without specific prior written permission. * * THIS SOFTWARE IS PROVIDED BY THE PROJECT AND CONTRIBUTORS ``AS IS'' AND * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE * ARE DISCLAIMED. IN NO EVENT SHALL THE PROJECT OR CONTRIBUTORS BE LIABLE * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF * SUCH DAMAGE. */ #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include "rtadvd.h" #include "advcap.h" #include "timer.h" #include "if.h" #include "config.h" #include "log.h" static void makeentry(char *, size_t, int, char *); static int getinet6sysctl(int); extern struct ralist ralist; void getconfig(intface) char *intface; { int stat, i; char tbuf[BUFSIZ]; struct rainfo *tmp; long val; int64_t val64; char buf[BUFSIZ]; char *bp = buf; char *addr; static int forwarding = -1; #define MUSTHAVE(var, cap) \ do { \ int64_t t; \ if ((t = agetnum(cap)) < 0) { \ log_warnx("need %s for interface %s", \ cap, intface); \ exit(1); \ } \ var = t; \ } while (0) #define MAYHAVE(var, cap, def) \ do { \ if ((var = agetnum(cap)) < 0) \ var = def; \ } while (0) if ((stat = agetent(tbuf, intface)) <= 0) { memset(tbuf, 0, sizeof(tbuf)); log_info("Could not parse configuration file for %s" " or the configuration file doesn't exist." " Treat it as default", intface); } if ((tmp = calloc(1, sizeof(*tmp))) == NULL) fatal("malloc"); TAILQ_INIT(&tmp->prefixes); SLIST_INIT(&tmp->soliciters); /* check if we are allowed to forward packets (if not determined) */ if (forwarding < 0) { if ((forwarding = getinet6sysctl(IPV6CTL_FORWARDING)) < 0) exit(1); } /* get interface information */ if (agetflag("nolladdr")) tmp->advlinkopt = 0; else tmp->advlinkopt = 1; if (tmp->advlinkopt) { if ((tmp->sdl = if_nametosdl(intface)) == NULL) { log_warnx("can't get information of %s", intface); exit(1); } tmp->ifindex = tmp->sdl->sdl_index; } else tmp->ifindex = if_nametoindex(intface); strncpy(tmp->ifname, intface, sizeof(tmp->ifname)); if ((tmp->phymtu = if_getmtu(intface)) == 0) { tmp->phymtu = IPV6_MMTU; log_warn("can't get interface mtu of %s. Treat as %d", intface, IPV6_MMTU); } /* * set router configuration variables. */ MAYHAVE(val, "maxinterval", DEF_MAXRTRADVINTERVAL); if (val < MIN_MAXINTERVAL || val > MAX_MAXINTERVAL) { log_warnx("maxinterval (%ld) on %s is invalid " "(must be between %e and %u)", val, intface, MIN_MAXINTERVAL, MAX_MAXINTERVAL); exit(1); } tmp->maxinterval = (u_int)val; MAYHAVE(val, "mininterval", tmp->maxinterval/3); if (val < MIN_MININTERVAL || val > (tmp->maxinterval * 3) / 4) { log_warnx("mininterval (%ld) on %s is invalid " "(must be between %e and %d)", val, intface, MIN_MININTERVAL, (tmp->maxinterval * 3) / 4); exit(1); } tmp->mininterval = (u_int)val; MAYHAVE(val, "chlim", DEF_ADVCURHOPLIMIT); tmp->hoplimit = val & 0xff; MAYHAVE(val, "raflags", 0); tmp->managedflg = val & ND_RA_FLAG_MANAGED; tmp->otherflg = val & ND_RA_FLAG_OTHER; #ifndef ND_RA_FLAG_RTPREF_MASK #define ND_RA_FLAG_RTPREF_MASK 0x18 /* 00011000 */ #define ND_RA_FLAG_RTPREF_RSV 0x10 /* 00010000 */ #endif tmp->rtpref = val & ND_RA_FLAG_RTPREF_MASK; if (tmp->rtpref == ND_RA_FLAG_RTPREF_RSV) { log_warnx("invalid router preference (%02x) on %s", tmp->rtpref, intface); exit(1); } MAYHAVE(val, "rltime", tmp->maxinterval * 3); if (val && (val < tmp->maxinterval || val > MAXROUTERLIFETIME)) { log_warnx("router lifetime (%ld) on %s is invalid " "(must be 0 or between %d and %d)", val, intface, tmp->maxinterval, MAXROUTERLIFETIME); exit(1); } /* * Basically, hosts MUST NOT send Router Advertisement messages at any * time (RFC 2461, Section 6.2.3). However, it would sometimes be * useful to allow hosts to advertise some parameters such as prefix * information and link MTU. Thus, we allow hosts to invoke rtadvd * only when router lifetime (on every advertising interface) is * explicitly set zero. (see also the above section) */ if (val && forwarding == 0) { log_warnx("non zero router lifetime is specified for %s, " "which must not be allowed for hosts. you must " "change router lifetime or enable IPv6 forwarding.", intface); exit(1); } tmp->lifetime = val & 0xffff; MAYHAVE(val, "rtime", DEF_ADVREACHABLETIME); if (val < 0 || val > MAXREACHABLETIME) { log_warnx("reachable time (%ld) on %s is invalid" " (must be no greater than %d)", val, intface, MAXREACHABLETIME); exit(1); } tmp->reachabletime = (u_int32_t)val; MAYHAVE(val64, "retrans", DEF_ADVRETRANSTIMER); if (val64 < 0 || val64 > 0xffffffff) { log_warnx("retrans time (%lld) on %s out of range", (long long)val64, intface); exit(1); } tmp->retranstimer = (u_int32_t)val64; if (agetnum("hapref") != -1 || agetnum("hatime") != -1) { log_warnx("mobile-ip6 configuration not supported"); exit(1); } /* prefix information */ /* * This is an implementation specific parameter to consider * link propagation delays and poorly synchronized clocks when * checking consistency of advertised lifetimes. */ MAYHAVE(val, "clockskew", 0); tmp->clockskew = val; tmp->pfxs = 0; for (i = -1; i < MAXPREFIX; i++) { struct prefix *pfx; char entbuf[256]; makeentry(entbuf, sizeof(entbuf), i, "addr"); addr = (char *)agetstr(entbuf, &bp); if (addr == NULL) continue; /* allocate memory to store prefix information */ if ((pfx = malloc(sizeof(struct prefix))) == NULL) fatal("malloc"); memset(pfx, 0, sizeof(*pfx)); /* link into chain */ TAILQ_INSERT_TAIL(&tmp->prefixes, pfx, entry); tmp->pfxs++; pfx->origin = PREFIX_FROM_CONFIG; if (inet_pton(AF_INET6, addr, &pfx->prefix) != 1) { log_warn("inet_pton failed for %s", addr); exit(1); } if (IN6_IS_ADDR_MULTICAST(&pfx->prefix)) { log_warnx("multicast prefix (%s) must" " not be advertised on %s", addr, intface); exit(1); } if (IN6_IS_ADDR_LINKLOCAL(&pfx->prefix)) log_info("link-local prefix (%s) will be" " advertised on %s", addr, intface); makeentry(entbuf, sizeof(entbuf), i, "prefixlen"); MAYHAVE(val, entbuf, 64); if (val < 0 || val > 128) { log_warnx("prefixlen (%ld) for %s " "on %s out of range", val, addr, intface); exit(1); } pfx->prefixlen = (int)val; makeentry(entbuf, sizeof(entbuf), i, "pinfoflags"); MAYHAVE(val, entbuf, (ND_OPT_PI_FLAG_ONLINK|ND_OPT_PI_FLAG_AUTO)); pfx->onlinkflg = val & ND_OPT_PI_FLAG_ONLINK; pfx->autoconfflg = val & ND_OPT_PI_FLAG_AUTO; makeentry(entbuf, sizeof(entbuf), i, "vltime"); MAYHAVE(val64, entbuf, DEF_ADVVALIDLIFETIME); if (val64 < 0 || val64 > 0xffffffff) { log_warnx("vltime (%lld) for" " %s/%d on %s is out of range", (long long)val64, addr, pfx->prefixlen, intface); exit(1); } pfx->validlifetime = (u_int32_t)val64; makeentry(entbuf, sizeof(entbuf), i, "vltimedecr"); if (agetflag(entbuf)) { struct timeval now; gettimeofday(&now, 0); pfx->vltimeexpire = now.tv_sec + pfx->validlifetime; } makeentry(entbuf, sizeof(entbuf), i, "pltime"); MAYHAVE(val64, entbuf, DEF_ADVPREFERREDLIFETIME); if (val64 < 0 || val64 > 0xffffffff) { log_warnx("pltime (%lld) for %s/%d on %s" " is out of range", (long long)val64, addr, pfx->prefixlen, intface); exit(1); } pfx->preflifetime = (u_int32_t)val64; makeentry(entbuf, sizeof(entbuf), i, "pltimedecr"); if (agetflag(entbuf)) { struct timeval now; gettimeofday(&now, 0); pfx->pltimeexpire = now.tv_sec + pfx->preflifetime; } } if (tmp->pfxs == 0) get_prefix(tmp); MAYHAVE(val, "mtu", 0); if (val < 0 || val > 0xffffffff) { log_warnx("mtu (%ld) on %s out of range", val, intface); exit(1); } tmp->linkmtu = (u_int32_t)val; if (tmp->linkmtu == 0) { char *mtustr; if ((mtustr = (char *)agetstr("mtu", &bp)) && strcmp(mtustr, "auto") == 0) tmp->linkmtu = tmp->phymtu; } else if (tmp->linkmtu < IPV6_MMTU || tmp->linkmtu > tmp->phymtu) { log_warnx("advertised link mtu (%lu) on %s is invalid (must" " be between least MTU (%d) and physical link MTU (%d)", (unsigned long)tmp->linkmtu, intface, IPV6_MMTU, tmp->phymtu); exit(1); } /* route information */ MAYHAVE(val, "routes", -1); if (val != -1) log_info("route information option is not available"); /* okey */ SLIST_INSERT_HEAD(&ralist, tmp, entry); /* construct the sending packet */ make_packet(tmp); /* set timer */ tmp->timer = rtadvd_add_timer(ra_timeout, ra_timer_update, tmp, tmp); ra_timer_update((void *)tmp, &tmp->timer->tm); rtadvd_set_timer(&tmp->timer->tm, tmp->timer); } void get_prefix(struct rainfo *rai) { struct ifaddrs *ifap, *ifa; struct prefix *pp; struct in6_addr *a; u_char *p, *ep, *m, *lim; u_char ntopbuf[INET6_ADDRSTRLEN]; if (getifaddrs(&ifap) < 0) fatal("can't get interface addresses"); for (ifa = ifap; ifa; ifa = ifa->ifa_next) { int plen; if (strcmp(ifa->ifa_name, rai->ifname) != 0) continue; if (ifa->ifa_addr->sa_family != AF_INET6) continue; a = &((struct sockaddr_in6 *)ifa->ifa_addr)->sin6_addr; if (IN6_IS_ADDR_LINKLOCAL(a)) continue; /* get prefix length */ m = (u_char *)&((struct sockaddr_in6 *)ifa->ifa_netmask)->sin6_addr; lim = (u_char *)(ifa->ifa_netmask) + ifa->ifa_netmask->sa_len; plen = prefixlen(m, lim); if (plen <= 0 || plen > 128) fatalx("failed to get prefixlen or prefix is invalid"); if (plen == 128) /* XXX */ continue; if (find_prefix(rai, a, plen)) { /* ignore a duplicated prefix. */ continue; } /* allocate memory to store prefix info. */ if ((pp = malloc(sizeof(*pp))) == NULL) fatal("malloc"); memset(pp, 0, sizeof(*pp)); /* set prefix, sweep bits outside of prefixlen */ pp->prefixlen = plen; memcpy(&pp->prefix, a, sizeof(*a)); if (1) { p = (u_char *)&pp->prefix; ep = (u_char *)(&pp->prefix + 1); while (m < lim && p < ep) *p++ &= *m++; while (p < ep) *p++ = 0x00; } if (!inet_ntop(AF_INET6, &pp->prefix, ntopbuf, sizeof(ntopbuf))) fatal("inet_ntop failed"); log_debug("add %s/%d to prefix list on %s", ntopbuf, pp->prefixlen, rai->ifname); /* set other fields with protocol defaults */ pp->validlifetime = DEF_ADVVALIDLIFETIME; pp->preflifetime = DEF_ADVPREFERREDLIFETIME; pp->onlinkflg = 1; pp->autoconfflg = 1; pp->origin = PREFIX_FROM_KERNEL; /* link into chain */ TAILQ_INSERT_TAIL(&rai->prefixes, pp, entry); /* counter increment */ rai->pfxs++; } freeifaddrs(ifap); } static void makeentry(buf, len, id, string) char *buf; size_t len; int id; char *string; { if (id < 0) strlcpy(buf, string, len); else snprintf(buf, len, "%s%d", string, id); } /* * Add a prefix to the list of specified interface and reconstruct * the outgoing packet. * The prefix must not be in the list. * XXX: other parameter of the prefix(e.g. lifetime) shoule be * able to be specified. */ static void add_prefix(struct rainfo *rai, struct in6_prefixreq *ipr) { struct prefix *prefix; u_char ntopbuf[INET6_ADDRSTRLEN]; if ((prefix = malloc(sizeof(*prefix))) == NULL) { log_warn("malloc"); return; /* XXX: error or exit? */ } memset(prefix, 0, sizeof(*prefix)); prefix->prefix = ipr->ipr_prefix.sin6_addr; prefix->prefixlen = ipr->ipr_plen; prefix->validlifetime = ipr->ipr_vltime; prefix->preflifetime = ipr->ipr_pltime; prefix->onlinkflg = ipr->ipr_raf_onlink; prefix->autoconfflg = ipr->ipr_raf_auto; prefix->origin = PREFIX_FROM_DYNAMIC; TAILQ_INSERT_TAIL(&rai->prefixes, prefix, entry); log_debug("new prefix %s/%d was added on %s", inet_ntop(AF_INET6, &ipr->ipr_prefix.sin6_addr, ntopbuf, INET6_ADDRSTRLEN), ipr->ipr_plen, rai->ifname); /* free the previous packet */ free(rai->ra_data); rai->ra_data = NULL; /* reconstruct the packet */ rai->pfxs++; make_packet(rai); /* * reset the timer so that the new prefix will be advertised quickly. */ rai->initcounter = 0; ra_timer_update((void *)rai, &rai->timer->tm); rtadvd_set_timer(&rai->timer->tm, rai->timer); } /* * Delete a prefix to the list of specified interface and reconstruct * the outgoing packet. * The prefix must be in the list. */ void delete_prefix(struct rainfo *rai, struct prefix *prefix) { u_char ntopbuf[INET6_ADDRSTRLEN]; TAILQ_REMOVE(&rai->prefixes, prefix, entry); log_debug("prefix %s/%d was deleted on %s", inet_ntop(AF_INET6, &prefix->prefix, ntopbuf, INET6_ADDRSTRLEN), prefix->prefixlen, rai->ifname); free(prefix); rai->pfxs--; make_packet(rai); } /* * Try to get an in6_prefixreq contents for a prefix which matches * ipr->ipr_prefix and ipr->ipr_plen and belongs to * the interface whose name is ipr->ipr_name[]. */ static int init_prefix(struct in6_prefixreq *ipr) { #if 0 int s; if ((s = socket(AF_INET6, SOCK_DGRAM, 0)) < 0) { log_warn("socket"); exit(1); } if (ioctl(s, SIOCGIFPREFIX_IN6, (caddr_t)ipr) < 0) { log_warn("ioctl:SIOCGIFFLAGS: failed for %s", ifr.ifr_name); ipr->ipr_vltime = DEF_ADVVALIDLIFETIME; ipr->ipr_pltime = DEF_ADVPREFERREDLIFETIME; ipr->ipr_raf_onlink = 1; ipr->ipr_raf_auto = 1; /* omit other field initialization */ } else if (ipr->ipr_origin < PR_ORIG_RR) { u_char ntopbuf[INET6_ADDRSTRLEN]; log_warn("Added prefix(%s)'s origin %d is" " lower than PR_ORIG_RR(router renumbering)." " This should not happen if I am router", inet_ntop(AF_INET6, &ipr->ipr_prefix.sin6_addr, ntopbuf, sizeof(ntopbuf)), ipr->ipr_origin); close(s); return 1; } close(s); return 0; #else ipr->ipr_vltime = DEF_ADVVALIDLIFETIME; ipr->ipr_pltime = DEF_ADVPREFERREDLIFETIME; ipr->ipr_raf_onlink = 1; ipr->ipr_raf_auto = 1; return 0; #endif } void make_prefix(struct rainfo *rai, int ifindex, struct in6_addr *addr, int plen) { struct in6_prefixreq ipr; memset(&ipr, 0, sizeof(ipr)); if (if_indextoname(ifindex, ipr.ipr_name) == NULL) { log_warn("Prefix added interface No.%d doesn't" " exist. This should not happen!", ifindex); exit(1); } ipr.ipr_prefix.sin6_len = sizeof(ipr.ipr_prefix); ipr.ipr_prefix.sin6_family = AF_INET6; ipr.ipr_prefix.sin6_addr = *addr; ipr.ipr_plen = plen; if (init_prefix(&ipr)) return; /* init failed by some error */ add_prefix(rai, &ipr); } void make_packet(struct rainfo *rainfo) { size_t packlen, lladdroptlen = 0; char *buf; struct nd_router_advert *ra; struct nd_opt_prefix_info *ndopt_pi; struct nd_opt_mtu *ndopt_mtu; struct prefix *pfx; /* calculate total length */ packlen = sizeof(struct nd_router_advert); if (rainfo->advlinkopt) { if ((lladdroptlen = lladdropt_length(rainfo->sdl)) == 0) { log_info("link-layer address option has" " null length on %s. Treat as not included.", rainfo->ifname); rainfo->advlinkopt = 0; } packlen += lladdroptlen; } if (rainfo->pfxs) packlen += sizeof(struct nd_opt_prefix_info) * rainfo->pfxs; if (rainfo->linkmtu) packlen += sizeof(struct nd_opt_mtu); /* allocate memory for the packet */ if ((buf = malloc(packlen)) == NULL) fatal("malloc"); if (rainfo->ra_data) { /* free the previous packet */ free(rainfo->ra_data); rainfo->ra_data = NULL; } rainfo->ra_data = buf; /* XXX: what if packlen > 576? */ rainfo->ra_datalen = packlen; /* * construct the packet */ ra = (struct nd_router_advert *)buf; ra->nd_ra_type = ND_ROUTER_ADVERT; ra->nd_ra_code = 0; ra->nd_ra_cksum = 0; ra->nd_ra_curhoplimit = (u_int8_t)(0xff & rainfo->hoplimit); ra->nd_ra_flags_reserved = 0; /* just in case */ /* * XXX: the router preference field, which is a 2-bit field, should be * initialized before other fields. */ ra->nd_ra_flags_reserved = 0xff & rainfo->rtpref; ra->nd_ra_flags_reserved |= rainfo->managedflg ? ND_RA_FLAG_MANAGED : 0; ra->nd_ra_flags_reserved |= rainfo->otherflg ? ND_RA_FLAG_OTHER : 0; ra->nd_ra_router_lifetime = htons(rainfo->lifetime); ra->nd_ra_reachable = htonl(rainfo->reachabletime); ra->nd_ra_retransmit = htonl(rainfo->retranstimer); buf += sizeof(*ra); if (rainfo->advlinkopt) { lladdropt_fill(rainfo->sdl, (struct nd_opt_hdr *)buf); buf += lladdroptlen; } if (rainfo->linkmtu) { ndopt_mtu = (struct nd_opt_mtu *)buf; ndopt_mtu->nd_opt_mtu_type = ND_OPT_MTU; ndopt_mtu->nd_opt_mtu_len = 1; ndopt_mtu->nd_opt_mtu_reserved = 0; ndopt_mtu->nd_opt_mtu_mtu = htonl(rainfo->linkmtu); buf += sizeof(struct nd_opt_mtu); } TAILQ_FOREACH(pfx, &rainfo->prefixes, entry) { u_int32_t vltime, pltime; struct timeval now; ndopt_pi = (struct nd_opt_prefix_info *)buf; ndopt_pi->nd_opt_pi_type = ND_OPT_PREFIX_INFORMATION; ndopt_pi->nd_opt_pi_len = 4; ndopt_pi->nd_opt_pi_prefix_len = pfx->prefixlen; ndopt_pi->nd_opt_pi_flags_reserved = 0; if (pfx->onlinkflg) ndopt_pi->nd_opt_pi_flags_reserved |= ND_OPT_PI_FLAG_ONLINK; if (pfx->autoconfflg) ndopt_pi->nd_opt_pi_flags_reserved |= ND_OPT_PI_FLAG_AUTO; if (pfx->vltimeexpire || pfx->pltimeexpire) gettimeofday(&now, NULL); if (pfx->vltimeexpire == 0) vltime = pfx->validlifetime; else vltime = (pfx->vltimeexpire > now.tv_sec) ? pfx->vltimeexpire - now.tv_sec : 0; if (pfx->pltimeexpire == 0) pltime = pfx->preflifetime; else pltime = (pfx->pltimeexpire > now.tv_sec) ? pfx->pltimeexpire - now.tv_sec : 0; if (vltime < pltime) { /* * this can happen if vltime is decrement but pltime * is not. */ pltime = vltime; } ndopt_pi->nd_opt_pi_valid_time = htonl(vltime); ndopt_pi->nd_opt_pi_preferred_time = htonl(pltime); ndopt_pi->nd_opt_pi_reserved2 = 0; ndopt_pi->nd_opt_pi_prefix = pfx->prefix; buf += sizeof(struct nd_opt_prefix_info); } return; } static int getinet6sysctl(int code) { int mib[] = { CTL_NET, PF_INET6, IPPROTO_IPV6, 0 }; int value; size_t size; mib[3] = code; size = sizeof(value); if (sysctl(mib, sizeof(mib)/sizeof(mib[0]), &value, &size, NULL, 0) < 0) { log_warn("failed to get ip6 sysctl(%d)", code); return(-1); } else return(value); }