/* $NetBSD: config.c,v 1.47 2021/11/27 22:30:26 rillig Exp $ */ /* $KAME: config.c,v 1.93 2005/10/17 14:40:02 suz 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 #ifdef __FreeBSD__ #include #endif #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 "logit.h" #include "prog_ops.h" #ifndef __arraycount #define __arraycount(__x) (sizeof(__x) / sizeof(__x[0])) #endif static time_t prefix_timo = (60 * 120); /* 2 hours. * XXX: should be configurable. */ static struct rtadvd_timer *prefix_timeout(void *); static void makeentry(char *, size_t, int, const char *); static int getinet6sysctl(int); static size_t encode_domain(char *dst, const char *src) { ssize_t len; char *odst, *p; odst = dst; while (src && (len = strlen(src)) != 0) { p = strchr(src, '.'); *dst++ = len = MIN(63, p == NULL ? len : p - src); memcpy(dst, src, len); dst += len; if (p == NULL) break; src = p + 1; } *dst++ = '\0'; return dst - odst; } void free_rainfo(struct rainfo *rai) { struct soliciter *sol; struct prefix *pfx; struct rtinfo *rti; struct rdnss *rdnss; struct rdnss_addr *rdnsa; struct dnssl *dnssl; struct dnssl_domain *dnsd; rtadvd_remove_timer(&rai->timer); rtadvd_remove_timer(&rai->timer_sol); while ((sol = TAILQ_FIRST(&rai->soliciter))) { TAILQ_REMOVE(&rai->soliciter, sol, next); free(sol); } while ((pfx = TAILQ_FIRST(&rai->prefix))) { TAILQ_REMOVE(&rai->prefix, pfx, next); free(pfx); } while ((rti = TAILQ_FIRST(&rai->route))) { TAILQ_REMOVE(&rai->route, rti, next); free(rti); } while ((rdnss = TAILQ_FIRST(&rai->rdnss))) { TAILQ_REMOVE(&rai->rdnss, rdnss, next); while ((rdnsa = TAILQ_FIRST(&rdnss->list))) { TAILQ_REMOVE(&rdnss->list, rdnsa, next); free(rdnsa); } free(rdnss); } while ((dnssl = TAILQ_FIRST(&rai->dnssl))) { TAILQ_REMOVE(&rai->dnssl, dnssl, next); while ((dnsd = TAILQ_FIRST(&dnssl->list))) { TAILQ_REMOVE(&dnssl->list, dnsd, next); free(dnsd); } free(dnssl); } free(rai->sdl); free(rai->ra_data); free(rai); } void getconfig(const char *intface, int exithard) { int stat, c, i; char tbuf[BUFSIZ]; struct rainfo *tmp, *rai; int32_t val; int64_t val64; char buf[BUFSIZ]; char *bp = buf; char *addr, *flagstr, *ap; static int forwarding = -1; char entbuf[256], abuf[256]; struct rdnss *rdnss; struct dnssl *dnssl; #define MUSTHAVE(var, cap) \ do { \ int64_t t; \ if ((t = agetnum(cap)) < 0) { \ logit(LOG_ERR, "%s: need %s for interface %s", \ __func__, cap, intface); \ goto errexit; \ } \ var = t; \ } while (0) #define MAYHAVE(var, cap, def) \ do { \ if ((var = agetnum(cap)) < 0) \ var = def; \ } while (0) #define ELM_MALLOC(p) \ do { \ p = calloc(1, sizeof(*p)); \ if (p == NULL) { \ logit(LOG_ERR, "%s: calloc failed: %m", \ __func__); \ goto errexit; \ } \ } while(/*CONSTCOND*/0) if (if_nametoindex(intface) == 0) { logit(LOG_INFO, "%s: interface %s not found, ignoring", __func__, intface); return; } logit(LOG_DEBUG, "%s: loading configuration for interface %s", __func__, intface); if ((stat = agetent(tbuf, intface)) <= 0) { memset(tbuf, 0, sizeof(tbuf)); logit(LOG_INFO, "%s: %s isn't defined in the configuration file" " or the configuration file doesn't exist." " Treat it as default", __func__, intface); } ELM_MALLOC(tmp); TAILQ_INIT(&tmp->soliciter); TAILQ_INIT(&tmp->prefix); TAILQ_INIT(&tmp->route); TAILQ_INIT(&tmp->rdnss); TAILQ_INIT(&tmp->dnssl); /* check if we are allowed to forward packets (if not determined) */ if (forwarding < 0) { if ((forwarding = getinet6sysctl(IPV6CTL_FORWARDING)) < 0) exit(EXIT_FAILURE); } /* get interface information */ if (agetflag("nolladdr")) tmp->advlinkopt = 0; else tmp->advlinkopt = 1; if (tmp->advlinkopt) { if ((tmp->sdl = if_nametosdl(intface)) == NULL) { logit(LOG_ERR, "%s: can't get information of %s", __func__, intface); goto errexit; } tmp->ifindex = tmp->sdl->sdl_index; } else { tmp->ifindex = if_nametoindex(intface); if (tmp->ifindex == 0) { logit(LOG_ERR, "%s: can't get information of %s", __func__, intface); goto errexit; } } tmp->ifflags = if_getflags(tmp->ifindex, 0); strlcpy(tmp->ifname, intface, sizeof(tmp->ifname)); if ((tmp->phymtu = if_getmtu(intface)) == 0) { tmp->phymtu = IPV6_MMTU; logit(LOG_WARNING, "%s: can't get interface mtu of %s. Treat as %d", __func__, intface, IPV6_MMTU); } /* * set router configuration variables. */ MAYHAVE(val, "maxinterval", DEF_MAXRTRADVINTERVAL); if (val < MIN_MAXINTERVAL || val > MAX_MAXINTERVAL) { logit(LOG_ERR, "%s: maxinterval (%d) on %s is invalid " "(must be between %u and %u)", __func__, val, intface, MIN_MAXINTERVAL, MAX_MAXINTERVAL); goto errexit; } tmp->maxinterval = val; MAYHAVE(val, "mininterval", tmp->maxinterval/3); if (val < MIN_MININTERVAL || val > (tmp->maxinterval * 3) / 4) { logit(LOG_ERR, "%s: mininterval (%d) on %s is invalid " "(must be between %u and %d)", __func__, val, intface, MIN_MININTERVAL, (tmp->maxinterval * 3) / 4); goto errexit; } tmp->mininterval = val; MAYHAVE(val, "chlim", DEF_ADVCURHOPLIMIT); tmp->hoplimit = val & 0xff; if ((flagstr = agetstr("raflags", &bp))) { val = 0; if (strchr(flagstr, 'm')) val |= ND_RA_FLAG_MANAGED; if (strchr(flagstr, 'o')) val |= ND_RA_FLAG_OTHER; if (strchr(flagstr, 'h')) val |= ND_RA_FLAG_RTPREF_HIGH; if (strchr(flagstr, 'l')) { if ((val & ND_RA_FLAG_RTPREF_HIGH)) { logit(LOG_ERR, "%s: the \'h\' and \'l\'" " router flags are exclusive", __func__); goto errexit; } val |= ND_RA_FLAG_RTPREF_LOW; } } else { 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) { logit(LOG_ERR, "%s: invalid router preference (%02x) on %s", __func__, tmp->rtpref, intface); goto errexit; } MAYHAVE(val, "rltime", DEF_ADVROUTERLIFETIME); if (val && (val < tmp->maxinterval || val > MAXROUTERLIFETIME)) { logit(LOG_ERR, "%s: router lifetime (%d) on %s is invalid " "(must be 0 or between %d and %d)", __func__, val, intface, tmp->maxinterval, MAXROUTERLIFETIME); goto errexit; } /* * 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) { logit(LOG_ERR, "%s: non zero router lifetime is specified for %s, " "which must not be allowed for hosts. you must " "change router lifetime or enable IPv6 forwarding.", __func__, intface); goto errexit; } tmp->lifetime = val & 0xffff; MAYHAVE(val, "rtime", DEF_ADVREACHABLETIME); if (val < 0 || val > MAXREACHABLETIME) { logit(LOG_ERR, "%s: reachable time (%d) on %s is invalid " "(must be no greater than %d)", __func__, val, intface, MAXREACHABLETIME); goto errexit; } tmp->reachabletime = (uint32_t)val; MAYHAVE(val64, "retrans", DEF_ADVRETRANSTIMER); if (val64 < 0 || val64 > 0xffffffff) { logit(LOG_ERR, "%s: retrans time (%lld) on %s out of range", __func__, (long long)val64, intface); goto errexit; } tmp->retranstimer = (uint32_t)val64; if (agetnum("hapref") != -1 || agetnum("hatime") != -1) { logit(LOG_ERR, "%s: mobile-ip6 configuration not supported", __func__); goto errexit; } /* 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; makeentry(entbuf, sizeof(entbuf), i, "addr"); addr = (char *)agetstr(entbuf, &bp); if (addr == NULL) continue; /* allocate memory to store prefix information */ if ((pfx = calloc(1, sizeof(*pfx))) == NULL) { logit(LOG_ERR, "%s: can't allocate memory: %m", __func__); goto errexit; } TAILQ_INSERT_TAIL(&tmp->prefix, pfx, next); tmp->pfxs++; pfx->rainfo = tmp; pfx->origin = PREFIX_FROM_CONFIG; if (inet_pton(AF_INET6, addr, &pfx->prefix) != 1) { logit(LOG_ERR, "%s: inet_pton failed for %s", __func__, addr); goto errexit; } if (IN6_IS_ADDR_MULTICAST(&pfx->prefix)) { logit(LOG_ERR, "%s: multicast prefix (%s) must " "not be advertised on %s", __func__, addr, intface); goto errexit; } if (IN6_IS_ADDR_LINKLOCAL(&pfx->prefix)) logit(LOG_NOTICE, "%s: link-local prefix (%s) will be" " advertised on %s", __func__, addr, intface); makeentry(entbuf, sizeof(entbuf), i, "prefixlen"); MAYHAVE(val, entbuf, 64); if (val < 0 || val > 128) { logit(LOG_ERR, "%s: prefixlen (%d) for %s " "on %s out of range", __func__, val, addr, intface); goto errexit; } pfx->prefixlen = (int)val; makeentry(entbuf, sizeof(entbuf), i, "pinfoflags"); if ((flagstr = (char *)agetstr(entbuf, &bp))) { val = 0; if (strchr(flagstr, 'l')) val |= ND_OPT_PI_FLAG_ONLINK; if (strchr(flagstr, 'a')) val |= ND_OPT_PI_FLAG_AUTO; } else { 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) { logit(LOG_ERR, "%s: vltime (%lld) for " "%s/%d on %s is out of range", __func__, (long long)val64, addr, pfx->prefixlen, intface); goto errexit; } pfx->validlifetime = (uint32_t)val64; makeentry(entbuf, sizeof(entbuf), i, "vltimedecr"); if (agetflag(entbuf)) { struct timespec now; prog_clock_gettime(CLOCK_MONOTONIC, &now); pfx->vltimeexpire = now.tv_sec + pfx->validlifetime; } makeentry(entbuf, sizeof(entbuf), i, "pltime"); MAYHAVE(val64, entbuf, DEF_ADVPREFERREDLIFETIME); if (val64 < 0 || val64 > 0xffffffff) { logit(LOG_ERR, "%s: pltime (%lld) for %s/%d on %s " "is out of range", __func__, (long long)val64, addr, pfx->prefixlen, intface); goto errexit; } pfx->preflifetime = (uint32_t)val64; makeentry(entbuf, sizeof(entbuf), i, "pltimedecr"); if (agetflag(entbuf)) { struct timespec now; prog_clock_gettime(CLOCK_MONOTONIC, &now); pfx->pltimeexpire = now.tv_sec + pfx->preflifetime; } } if (TAILQ_FIRST(&tmp->prefix) == NULL && !agetflag("noifprefix")) get_prefix(tmp); MAYHAVE(val64, "mtu", 0); if (val64 < 0 || val64 > 0xffffffff) { logit(LOG_ERR, "%s: mtu (%" PRIi64 ") on %s out of range", __func__, val64, intface); goto errexit; } tmp->linkmtu = (uint32_t)val64; 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) { logit(LOG_ERR, "%s: advertised link mtu (%d) on %s is invalid (must " "be between least MTU (%d) and physical link MTU (%d)", __func__, tmp->linkmtu, intface, IPV6_MMTU, tmp->phymtu); goto errexit; } /* route information */ for (i = -1; i < MAXROUTE; i++) { struct rtinfo *rti; char oentbuf[256]; makeentry(entbuf, sizeof(entbuf), i, "rtprefix"); addr = (char *)agetstr(entbuf, &bp); if (addr == NULL) { makeentry(oentbuf, sizeof(oentbuf), i, "rtrprefix"); addr = (char *)agetstr(oentbuf, &bp); if (addr) { fprintf(stderr, "%s was obsoleted. Use %s.\n", oentbuf, entbuf); } } if (addr == NULL) continue; ELM_MALLOC(rti); memset(rti, 0, sizeof(*rti)); /* link into chain */ TAILQ_INSERT_TAIL(&tmp->route, rti, next); if (inet_pton(AF_INET6, addr, &rti->prefix) != 1) { logit(LOG_ERR, "%s: inet_pton failed for %s", __func__, addr); goto errexit; } #if 0 /* * XXX: currently there's no restriction in route information * prefix according to * draft-ietf-ipngwg-router-selection-00.txt. * However, I think the similar restriction be necessary. */ MAYHAVE(val64, entbuf, DEF_ADVVALIDLIFETIME); if (IN6_IS_ADDR_MULTICAST(&rti->prefix)) { logit(LOG_ERR, "%s: multicast route (%s) must " "not be advertised on %s", __func__, addr, intface); goto errexit; } if (IN6_IS_ADDR_LINKLOCAL(&rti->prefix)) { logit(LOG_NOTICE, "%s: link-local route (%s) will " "be advertised on %s", __func__, addr, intface); goto errexit; } #endif makeentry(entbuf, sizeof(entbuf), i, "rtplen"); /* XXX: 256 is a magic number for compatibility check. */ MAYHAVE(val, entbuf, 256); if (val == 256) { makeentry(oentbuf, sizeof(oentbuf), i, "rtrplen"); MAYHAVE(val, oentbuf, 256); if (val != 256) { fprintf(stderr, "%s was obsoleted. Use %s.\n", oentbuf, entbuf); } else val = 64; } if (val < 0 || val > 128) { logit(LOG_ERR, "%s: prefixlen (%d) for %s on %s " "out of range", __func__, val, addr, intface); goto errexit; } rti->prefixlen = (int)val; makeentry(entbuf, sizeof(entbuf), i, "rtflags"); if ((flagstr = (char *)agetstr(entbuf, &bp))) { val = 0; if (strchr(flagstr, 'h')) val |= ND_RA_FLAG_RTPREF_HIGH; if (strchr(flagstr, 'l')) { if ((val & ND_RA_FLAG_RTPREF_HIGH)) { logit(LOG_ERR, "%s: the \'h\' and \'l\' route" " preferences are exclusive", __func__); goto errexit; } val |= ND_RA_FLAG_RTPREF_LOW; } } else MAYHAVE(val, entbuf, 256); /* XXX */ if (val == 256) { makeentry(oentbuf, sizeof(oentbuf), i, "rtrflags"); MAYHAVE(val, oentbuf, 256); if (val != 256) { fprintf(stderr, "%s was obsoleted. Use %s.\n", oentbuf, entbuf); } else val = 0; } rti->rtpref = val & ND_RA_FLAG_RTPREF_MASK; if (rti->rtpref == ND_RA_FLAG_RTPREF_RSV) { logit(LOG_ERR, "%s: invalid route preference (%02x) " "for %s/%d on %s", __func__, rti->rtpref, addr, rti->prefixlen, intface); goto errexit; } /* * Since the spec does not a default value, we should make * this entry mandatory. However, FreeBSD 4.4 has shipped * with this field being optional, we use the router lifetime * as an ad-hoc default value with a warning message. */ makeentry(entbuf, sizeof(entbuf), i, "rtltime"); MAYHAVE(val64, entbuf, -1); if (val64 == -1) { makeentry(oentbuf, sizeof(oentbuf), i, "rtrltime"); MAYHAVE(val64, oentbuf, -1); if (val64 != -1) { fprintf(stderr, "%s was obsoleted. Use %s.\n", oentbuf, entbuf); } else { fprintf(stderr, "%s should be specified " "for interface %s.\n", entbuf, intface); val64 = tmp->lifetime; } } if (val64 < 0 || val64 > 0xffffffff) { logit(LOG_ERR, "%s: route lifetime (%lld) for " "%s/%d on %s out of range", __func__, (long long)val64, addr, rti->prefixlen, intface); goto errexit; } rti->ltime = (uint32_t)val64; } /* RDNSS */ for (i = -1; i < MAXRDNSS; i++) { struct rdnss_addr *rdnsa; makeentry(entbuf, sizeof(entbuf), i, "rdnss"); addr = (char *)agetstr(entbuf, &bp); if (addr == NULL) continue; ELM_MALLOC(rdnss); TAILQ_INSERT_TAIL(&tmp->rdnss, rdnss, next); TAILQ_INIT(&rdnss->list); for (ap = addr; ap - addr < (ssize_t)strlen(addr); ap += c+1) { c = strcspn(ap, ","); strncpy(abuf, ap, c); abuf[c] = '\0'; ELM_MALLOC(rdnsa); TAILQ_INSERT_TAIL(&rdnss->list, rdnsa, next); if (inet_pton(AF_INET6, abuf, &rdnsa->addr) != 1) { logit(LOG_ERR, "%s: inet_pton failed for %s", __func__, addr); goto errexit; } } makeentry(entbuf, sizeof(entbuf), i, "rdnssltime"); MAYHAVE(val64, entbuf, tmp->maxinterval * 3 / 2); if (val64 < 0 || val64 > 0xffffffff) { logit(LOG_ERR, "%s: %s (%lld) on %s is invalid", __func__, entbuf, (long long)val64, intface); goto errexit; } rdnss->lifetime = (uint32_t)val64; } /* DNSSL */ TAILQ_INIT(&tmp->dnssl); for (i = -1; i < MAXDNSSL; i++) { struct dnssl_domain *dnsd; makeentry(entbuf, sizeof(entbuf), i, "dnssl"); addr = (char *)agetstr(entbuf, &bp); if (addr == NULL) continue; ELM_MALLOC(dnssl); TAILQ_INSERT_TAIL(&tmp->dnssl, dnssl, next); TAILQ_INIT(&dnssl->list); for (ap = addr; ap - addr < (ssize_t)strlen(addr); ap += c+1) { c = strcspn(ap, ","); strncpy(abuf, ap, c); abuf[c] = '\0'; ELM_MALLOC(dnsd); TAILQ_INSERT_TAIL(&dnssl->list, dnsd, next); dnsd->len = encode_domain(dnsd->domain, abuf); } makeentry(entbuf, sizeof(entbuf), i, "dnsslltime"); MAYHAVE(val64, entbuf, tmp->maxinterval * 3 / 2); if (val64 < 0 || val64 > 0xffffffff) { logit(LOG_ERR, "%s: %s (%lld) on %s is invalid", __func__, entbuf, (long long)val64, intface); goto errexit; } dnssl->lifetime = (uint32_t)val64; } TAILQ_FOREACH(rai, &ralist, next) { if (rai->ifindex == tmp->ifindex) { TAILQ_REMOVE(&ralist, rai, next); if (Cflag) { free_rainfo(rai); rai = NULL; break; } /* If we already have a leaving RA use that * as this config hasn't been advertised */ if (rai->leaving) { tmp->leaving = rai->leaving; free_rainfo(rai); rai = tmp->leaving; rai->leaving_for = tmp; break; } rai->lifetime = 0; TAILQ_FOREACH(rdnss, &rai->rdnss, next) rdnss->lifetime = 0; TAILQ_FOREACH(dnssl, &rai->dnssl, next) dnssl->lifetime = 0; rai->leaving_for = tmp; tmp->leaving = rai; rai->initcounter = MAX_INITIAL_RTR_ADVERTISEMENTS; rai->mininterval = MIN_DELAY_BETWEEN_RAS; rai->maxinterval = MIN_DELAY_BETWEEN_RAS; rai->leaving_adv = MAX_FINAL_RTR_ADVERTISEMENTS; if (rai->timer == NULL) rai->timer = rtadvd_add_timer(ra_timeout, ra_timer_update, rai, rai); ra_timer_update((void *)rai, &rai->timer->tm); rtadvd_set_timer(&rai->timer->tm, rai->timer); break; } } /* okey */ TAILQ_INSERT_TAIL(&ralist, tmp, next); /* construct the sending packet */ make_packet(tmp); /* set timer */ if (rai) return; tmp->timer = rtadvd_add_timer(ra_timeout, ra_timer_update, tmp, tmp); ra_timer_set_short_delay(tmp, tmp->timer); tmp->timer_sol = rtadvd_add_timer(ra_timeout_sol, NULL, tmp, NULL); return; errexit: if (exithard) exit(EXIT_FAILURE); free_rainfo(tmp); } void get_prefix(struct rainfo *rai) { struct ifaddrs *ifap, *ifa; struct prefix *pp; struct in6_addr *a; unsigned char *p, *ep, *m, *lim; char ntopbuf[INET6_ADDRSTRLEN]; if (getifaddrs(&ifap) < 0) { logit(LOG_ERR, "%s: can't get interface addresses", __func__); exit(EXIT_FAILURE); } 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 = (unsigned char *)&((struct sockaddr_in6 *)ifa->ifa_netmask)->sin6_addr; lim = (unsigned char *)(ifa->ifa_netmask) + ifa->ifa_netmask->sa_len; plen = prefixlen(m, lim); if (plen <= 0 || plen > 128) { logit(LOG_ERR, "%s: failed to get prefixlen " "or prefix is invalid", __func__); exit(EXIT_FAILURE); } if (plen == 128) /* XXX */ continue; if (find_prefix(rai, a, plen)) { /* ignore a duplicated prefix. */ continue; } /* allocate memory to store prefix info. */ if ((pp = calloc(1, sizeof(*pp))) == NULL) { logit(LOG_ERR, "%s: can't get allocate buffer for prefix", __func__); exit(EXIT_FAILURE); } /* set prefix, sweep bits outside of prefixlen */ pp->prefixlen = plen; memcpy(&pp->prefix, a, sizeof(*a)); if (1) { p = (unsigned char *)&pp->prefix; ep = (unsigned 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))) { logit(LOG_ERR, "%s: inet_ntop failed", __func__); exit(EXIT_FAILURE); } logit(LOG_DEBUG, "%s: add %s/%d to prefix list on %s", __func__, 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; pp->rainfo = rai; /* link into chain */ TAILQ_INSERT_TAIL(&rai->prefix, pp, next); rai->pfxs++; } freeifaddrs(ifap); } static void makeentry(char *buf, size_t len, int id, const char *string) { if (id < 0) strlcpy(buf, string, len); else snprintf(buf, len, "%s%d", string, id); } /* * 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 prefix *prefix) { char ntopbuf[INET6_ADDRSTRLEN]; struct rainfo *rai = prefix->rainfo; TAILQ_REMOVE(&rai->prefix, prefix, next); rai->pfxs--; logit(LOG_DEBUG, "%s: prefix %s/%d was deleted on %s", __func__, inet_ntop(AF_INET6, &prefix->prefix, ntopbuf, INET6_ADDRSTRLEN), prefix->prefixlen, rai->ifname); rtadvd_remove_timer(&prefix->timer); free(prefix); } void invalidate_prefix(struct prefix *prefix) { char ntopbuf[INET6_ADDRSTRLEN]; struct timespec timo; struct rainfo *rai = prefix->rainfo; if (prefix->timer) { /* sanity check */ logit(LOG_ERR, "%s: assumption failure: timer already exists", __func__); exit(EXIT_FAILURE); } logit(LOG_DEBUG, "%s: prefix %s/%d was invalidated on %s, " "will expire in %ld seconds", __func__, inet_ntop(AF_INET6, &prefix->prefix, ntopbuf, INET6_ADDRSTRLEN), prefix->prefixlen, rai->ifname, (long)prefix_timo); /* set the expiration timer */ prefix->timer = rtadvd_add_timer(prefix_timeout, NULL, prefix, NULL); if (prefix->timer == NULL) { logit(LOG_ERR, "%s: failed to add a timer for a prefix. " "remove the prefix", __func__); delete_prefix(prefix); } timo.tv_sec = prefix_timo; timo.tv_nsec = 0; rtadvd_set_timer(&timo, prefix->timer); } static struct rtadvd_timer * prefix_timeout(void *arg) { struct prefix *prefix = (struct prefix *)arg; delete_prefix(prefix); return(NULL); } void update_prefix(struct prefix * prefix) { char ntopbuf[INET6_ADDRSTRLEN]; struct rainfo *rai = prefix->rainfo; if (prefix->timer == NULL) { /* sanity check */ logit(LOG_ERR, "%s: assumption failure: timer does not exist", __func__); exit(EXIT_FAILURE); } logit(LOG_DEBUG, "%s: prefix %s/%d was re-enabled on %s", __func__, inet_ntop(AF_INET6, &prefix->prefix, ntopbuf, INET6_ADDRSTRLEN), prefix->prefixlen, rai->ifname); /* stop the expiration timer */ rtadvd_remove_timer(&prefix->timer); } /* * Add a prefix to the list of specified interface and reconstruct * the outgoing packet. * The prefix must not be in the list. * XXX: other parameters of the prefix(e.g. lifetime) should be * able to be specified. */ void add_prefix(struct rainfo *rai, int ifindex, const struct in6_addr *addr, int plen) { struct prefix *prefix; char ntopbuf[INET6_ADDRSTRLEN]; if ((prefix = calloc(1, sizeof(*prefix))) == NULL) { logit(LOG_ERR, "%s: memory allocation failed", __func__); return; /* XXX: error or exit? */ } prefix->prefix = *addr; prefix->prefixlen = plen; prefix->validlifetime = DEF_ADVVALIDLIFETIME; prefix->preflifetime = DEF_ADVPREFERREDLIFETIME; prefix->onlinkflg = 1; prefix->autoconfflg = 0; prefix->origin = PREFIX_FROM_DYNAMIC; prefix->rainfo = rai; TAILQ_INSERT_TAIL(&rai->prefix, prefix, next); rai->pfxs++; logit(LOG_DEBUG, "%s: new prefix %s/%d was added on %s", __func__, inet_ntop(AF_INET6, addr, ntopbuf, INET6_ADDRSTRLEN), plen, rai->ifname); /* free the previous packet */ free(rai->ra_data); rai->ra_data = NULL; /* reconstruct the packet */ make_packet(rai); } 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; struct nd_opt_route_info *ndopt_rti; struct rtinfo *rti; struct nd_opt_rdnss *ndopt_rdnss; struct rdnss *rdns; struct rdnss_addr *rdnsa; struct nd_opt_dnssl *ndopt_dnssl; struct dnssl *dnsl; struct dnssl_domain *dnsd; size_t len, plen; /* calculate total length */ packlen = sizeof(struct nd_router_advert); if (rainfo->advlinkopt) { if ((lladdroptlen = lladdropt_length(rainfo->sdl)) == 0) { logit(LOG_INFO, "%s: link-layer address option has" " null length on %s. Treat as not included.", __func__, rainfo->ifname); rainfo->advlinkopt = 0; } packlen += lladdroptlen; } if (TAILQ_FIRST(&rainfo->prefix) != NULL) packlen += sizeof(struct nd_opt_prefix_info) * rainfo->pfxs; if (rainfo->linkmtu) packlen += sizeof(struct nd_opt_mtu); TAILQ_FOREACH(rti, &rainfo->route, next) packlen += sizeof(struct nd_opt_route_info) + ((rti->prefixlen + 0x3f) >> 6) * 8; TAILQ_FOREACH(rdns, &rainfo->rdnss, next) { packlen += sizeof(struct nd_opt_rdnss); TAILQ_FOREACH(rdnsa, &rdns->list, next) packlen += sizeof(rdnsa->addr); } TAILQ_FOREACH(dnsl, &rainfo->dnssl, next) { packlen += sizeof(struct nd_opt_dnssl); len = 0; TAILQ_FOREACH(dnsd, &dnsl->list, next) len += dnsd->len; len += len % 8 ? 8 - len % 8 : 0; packlen += len; } /* allocate memory for the packet */ if ((buf = realloc(rainfo->ra_data, packlen)) == NULL) { logit(LOG_ERR, "%s: can't get enough memory for an RA packet %m", __func__); exit(EXIT_FAILURE); } rainfo->ra_data = buf; /* XXX: what if packlen > 576? */ rainfo->ra_datalen = packlen; #define CHECKLEN(size) \ do { \ if (buf + size > rainfo->ra_data + packlen) { \ logit(LOG_ERR, \ "%s: @%d RA packet does not fit in %zu",\ __func__, __LINE__, packlen); \ exit(EXIT_FAILURE); \ } \ } while (0) /* * construct the packet */ CHECKLEN(sizeof(*ra)); 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 = (uint8_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) { CHECKLEN(sizeof(struct nd_opt_hdr)); lladdropt_fill(rainfo->sdl, (struct nd_opt_hdr *)buf); buf += lladdroptlen; } if (rainfo->linkmtu) { CHECKLEN(sizeof(*ndopt_mtu)); 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->prefix, next) { uint32_t vltime, pltime; struct timespec now; CHECKLEN(sizeof(*ndopt_pi)); 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->timer) vltime = 0; else { if (pfx->vltimeexpire || pfx->pltimeexpire) prog_clock_gettime(CLOCK_MONOTONIC, &now); if (pfx->vltimeexpire == 0) vltime = pfx->validlifetime; else vltime = (pfx->vltimeexpire > now.tv_sec) ? pfx->vltimeexpire - now.tv_sec : 0; } if (pfx->timer) pltime = 0; else { 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); } TAILQ_FOREACH(rti, &rainfo->route, next) { uint8_t psize = (rti->prefixlen + 0x3f) >> 6; CHECKLEN(sizeof(*ndopt_rti)); ndopt_rti = (struct nd_opt_route_info *)buf; ndopt_rti->nd_opt_rti_type = ND_OPT_ROUTE_INFO; ndopt_rti->nd_opt_rti_len = 1 + psize; ndopt_rti->nd_opt_rti_prefixlen = rti->prefixlen; ndopt_rti->nd_opt_rti_flags = 0xff & rti->rtpref; ndopt_rti->nd_opt_rti_lifetime = htonl(rti->ltime); memcpy(ndopt_rti + 1, &rti->prefix, psize * 8); buf += sizeof(struct nd_opt_route_info) + psize * 8; } TAILQ_FOREACH(rdns, &rainfo->rdnss, next) { CHECKLEN(sizeof(*ndopt_rdnss)); ndopt_rdnss = (struct nd_opt_rdnss *)buf; ndopt_rdnss->nd_opt_rdnss_type = ND_OPT_RDNSS; ndopt_rdnss->nd_opt_rdnss_len = 1; ndopt_rdnss->nd_opt_rdnss_reserved = 0; ndopt_rdnss->nd_opt_rdnss_lifetime = htonl(rdns->lifetime); buf += sizeof(*ndopt_rdnss); TAILQ_FOREACH(rdnsa, &rdns->list, next) { CHECKLEN(sizeof(rdnsa->addr)); memcpy(buf, &rdnsa->addr, sizeof(rdnsa->addr)); ndopt_rdnss->nd_opt_rdnss_len += 2; buf += sizeof(rdnsa->addr); } } TAILQ_FOREACH(dnsl, &rainfo->dnssl, next) { CHECKLEN(sizeof(*ndopt_dnssl)); ndopt_dnssl = (struct nd_opt_dnssl *)buf; ndopt_dnssl->nd_opt_dnssl_type = ND_OPT_DNSSL; ndopt_dnssl->nd_opt_dnssl_len = 0; ndopt_dnssl->nd_opt_dnssl_reserved = 0; ndopt_dnssl->nd_opt_dnssl_lifetime = htonl(dnsl->lifetime); buf += sizeof(*ndopt_dnssl); TAILQ_FOREACH(dnsd, &dnsl->list, next) { CHECKLEN(dnsd->len); memcpy(buf, dnsd->domain, dnsd->len); buf += dnsd->len; } /* Ensure our length is padded correctly */ len = buf - (char *)ndopt_dnssl; plen = len % 8 ? 8 - len % 8 : 0; CHECKLEN(plen); memset(buf, 0, plen); buf += plen; ndopt_dnssl->nd_opt_dnssl_len = (len + plen) / 8; } memset(buf, 0, packlen - (buf - rainfo->ra_data)); } static int getinet6sysctl(int code) { const int mib[] = { CTL_NET, PF_INET6, IPPROTO_IPV6, code }; int value; size_t size; size = sizeof(value); if (prog_sysctl(mib, __arraycount(mib), &value, &size, NULL, 0) == -1) { logit(LOG_ERR, "%s: failed to get ip6 sysctl(%d): %m", __func__, code); return -1; } return value; }