/* $NetBSD: rrenum.c,v 1.15 2012/12/13 15:36:36 roy Exp $ */ /* $KAME: rrenum.c,v 1.14 2004/06/14 05:36:00 itojun Exp $ */ /* * Copyright (C) 1995, 1996, 1997, and 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 #ifdef __FreeBSD__ #include #endif #include #include #include #include #include #include #include #include #include #include "rtadvd.h" #include "rrenum.h" #include "if.h" #define RR_ISSET_SEGNUM(segnum_bits, segnum) \ ((((segnum_bits)[(segnum) >> 5]) & (1 << ((segnum) & 31))) != 0) #define RR_SET_SEGNUM(segnum_bits, segnum) \ (((segnum_bits)[(segnum) >> 5]) |= (1 << ((segnum) & 31))) struct rr_operation { u_long rro_seqnum; u_long rro_segnum_bits[8]; }; static struct rr_operation rro; static int rr_rcvifindex; static int rrcmd2pco[RPM_PCO_MAX] = { 0, SIOCAIFPREFIX_IN6, SIOCCIFPREFIX_IN6, SIOCSGIFPREFIX_IN6 }; static int s = -1; /* * Check validity of a Prefix Control Operation(PCO). * Return 0 on success, 1 on failure. */ static int rr_pco_check(int len, struct rr_pco_match *rpm) { struct rr_pco_use *rpu, *rpulim; int checklen; /* rpm->rpm_len must be (4N * 3) as router-renum-05.txt */ if ((rpm->rpm_len - 3) < 0 || /* must be at least 3 */ (rpm->rpm_len - 3) & 0x3) { /* must be multiple of 4 */ syslog(LOG_WARNING, "<%s> rpm_len %d is not 4N * 3", __func__, rpm->rpm_len); return 1; } /* rpm->rpm_code must be valid value */ switch (rpm->rpm_code) { case RPM_PCO_ADD: case RPM_PCO_CHANGE: case RPM_PCO_SETGLOBAL: break; default: syslog(LOG_WARNING, "<%s> unknown rpm_code %d", __func__, rpm->rpm_code); return 1; } /* rpm->rpm_matchlen must be 0 to 128 inclusive */ if (rpm->rpm_matchlen > 128) { syslog(LOG_WARNING, "<%s> rpm_matchlen %d is over 128", __func__, rpm->rpm_matchlen); return 1; } /* * rpu->rpu_uselen, rpu->rpu_keeplen, and sum of them must be * between 0 and 128 inclusive */ for (rpu = (struct rr_pco_use *)(rpm + 1), rpulim = (struct rr_pco_use *)((char *)rpm + len); rpu < rpulim; rpu += 1) { checklen = rpu->rpu_uselen; checklen += rpu->rpu_keeplen; /* * omit these check, because either of rpu_uselen * and rpu_keeplen is unsigned char * (128 > rpu_uselen > 0) * (128 > rpu_keeplen > 0) * (rpu_uselen + rpu_keeplen > 0) */ if (checklen > 128) { syslog(LOG_WARNING, "<%s> sum of rpu_uselen %d and" " rpu_keeplen %d is %d(over 128)", __func__, rpu->rpu_uselen, rpu->rpu_keeplen, rpu->rpu_uselen + rpu->rpu_keeplen); return 1; } } return 0; } static void do_use_prefix(int len, struct rr_pco_match *rpm, struct in6_rrenumreq *irr, int ifindex) { struct rr_pco_use *rpu, *rpulim; struct rainfo *rai; struct prefix *pp; rpu = (struct rr_pco_use *)(rpm + 1); rpulim = (struct rr_pco_use *)((char *)rpm + len); if (rpu == rpulim) { /* no use prefix */ if (rpm->rpm_code == RPM_PCO_ADD) return; irr->irr_u_uselen = 0; irr->irr_u_keeplen = 0; irr->irr_raf_mask_onlink = 0; irr->irr_raf_mask_auto = 0; irr->irr_vltime = 0; irr->irr_pltime = 0; memset(&irr->irr_flags, 0, sizeof(irr->irr_flags)); irr->irr_useprefix.sin6_len = 0; /* let it mean, no addition */ irr->irr_useprefix.sin6_family = 0; irr->irr_useprefix.sin6_addr = in6addr_any; if (ioctl(s, rrcmd2pco[rpm->rpm_code], irr) < 0 && errno != EADDRNOTAVAIL) syslog(LOG_ERR, "<%s> ioctl: %s", __func__, strerror(errno)); return; } for (rpu = (struct rr_pco_use *)(rpm + 1), rpulim = (struct rr_pco_use *)((char *)rpm + len); rpu < rpulim; rpu += 1) { /* init in6_rrenumreq fields */ irr->irr_u_uselen = rpu->rpu_uselen; irr->irr_u_keeplen = rpu->rpu_keeplen; irr->irr_raf_mask_onlink = !!(rpu->rpu_ramask & ICMP6_RR_PCOUSE_RAFLAGS_ONLINK); irr->irr_raf_mask_auto = !!(rpu->rpu_ramask & ICMP6_RR_PCOUSE_RAFLAGS_AUTO); irr->irr_vltime = ntohl(rpu->rpu_vltime); irr->irr_pltime = ntohl(rpu->rpu_pltime); irr->irr_raf_onlink = (rpu->rpu_raflags & ICMP6_RR_PCOUSE_RAFLAGS_ONLINK) == 0 ? 0 : 1; irr->irr_raf_auto = (rpu->rpu_raflags & ICMP6_RR_PCOUSE_RAFLAGS_AUTO) == 0 ? 0 : 1; irr->irr_rrf_decrvalid = (rpu->rpu_flags & ICMP6_RR_PCOUSE_FLAGS_DECRVLTIME) == 0 ? 0 : 1; irr->irr_rrf_decrprefd = (rpu->rpu_flags & ICMP6_RR_PCOUSE_FLAGS_DECRPLTIME) == 0 ? 0 : 1; irr->irr_useprefix.sin6_len = sizeof(irr->irr_useprefix); irr->irr_useprefix.sin6_family = AF_INET6; irr->irr_useprefix.sin6_addr = rpu->rpu_prefix; if (ioctl(s, rrcmd2pco[rpm->rpm_code], irr) < 0 && errno != EADDRNOTAVAIL) syslog(LOG_ERR, "<%s> ioctl: %s", __func__, strerror(errno)); /* very adhoc: should be rewritten */ if (rpm->rpm_code == RPM_PCO_CHANGE && IN6_ARE_ADDR_EQUAL(&rpm->rpm_prefix, &rpu->rpu_prefix) && rpm->rpm_matchlen == rpu->rpu_uselen && rpu->rpu_uselen == rpu->rpu_keeplen) { if ((rai = if_indextorainfo(ifindex)) == NULL) continue; /* non-advertising IF */ TAILQ_FOREACH(pp, &rai->prefix, next) { struct timeval now; if (prefix_match(&pp->prefix, pp->prefixlen, &rpm->rpm_prefix, rpm->rpm_matchlen)) { /* change parameters */ pp->validlifetime = ntohl(rpu->rpu_vltime); pp->preflifetime = ntohl(rpu->rpu_pltime); if (irr->irr_rrf_decrvalid) { gettimeofday(&now, 0); pp->vltimeexpire = now.tv_sec + pp->validlifetime; } else pp->vltimeexpire = 0; if (irr->irr_rrf_decrprefd) { gettimeofday(&now, 0); pp->pltimeexpire = now.tv_sec + pp->preflifetime; } else pp->pltimeexpire = 0; } } } } } /* * process a Prefix Control Operation(PCO). * return 0 on success, 1 on failure */ static int do_pco(struct icmp6_router_renum *rr, int len, struct rr_pco_match *rpm) { int ifindex = 0; struct in6_rrenumreq irr; struct rainfo *rai; if ((rr_pco_check(len, rpm) != 0)) return 1; if (s == -1 && (s = socket(AF_INET6, SOCK_DGRAM, 0)) < 0) { syslog(LOG_ERR, "<%s> socket: %s", __func__, strerror(errno)); exit(1); } memset(&irr, 0, sizeof(irr)); irr.irr_origin = PR_ORIG_RR; irr.irr_m_len = rpm->rpm_matchlen; irr.irr_m_minlen = rpm->rpm_minlen; irr.irr_m_maxlen = rpm->rpm_maxlen; irr.irr_matchprefix.sin6_len = sizeof(irr.irr_matchprefix); irr.irr_matchprefix.sin6_family = AF_INET6; irr.irr_matchprefix.sin6_addr = rpm->rpm_prefix; /* * if ICMP6_RR_FLAGS_FORCEAPPLY(A flag) is 0 and IFF_UP is off, * the interface is not applied */ if (rr->rr_flags & ICMP6_RR_FLAGS_FORCEAPPLY) { while (if_indextoname(++ifindex, irr.irr_name)) { rai = if_indextorainfo(ifindex); if (rai && (rai->ifflags & IFF_UP)) { /* TODO: interface scope check */ do_use_prefix(len, rpm, &irr, ifindex); } } } if (errno == ENXIO) return 0; else if (errno) { syslog(LOG_ERR, "<%s> if_indextoname: %s", __func__, strerror(errno)); return 1; } return 0; } /* * call do_pco() for each Prefix Control Operations(PCOs) in a received * Router Renumbering Command packet. * return 0 on success, 1 on failure */ static int do_rr(size_t len, struct icmp6_router_renum *rr) { struct rr_pco_match *rpm; char *cp, *lim; lim = (char *)rr + len; cp = (char *)(rr + 1); len -= sizeof(struct icmp6_router_renum); while (cp < lim) { size_t rpmlen; rpm = (struct rr_pco_match *)cp; if (len < sizeof(struct rr_pco_match)) { tooshort: syslog(LOG_ERR, "<%s> pkt too short. left len = %zd. " "gabage at end of pkt?", __func__, len); return 1; } rpmlen = rpm->rpm_len << 3; if (len < rpmlen) goto tooshort; if (do_pco(rr, rpmlen, rpm)) { syslog(LOG_WARNING, "<%s> invalid PCO", __func__); goto next; } next: cp += rpmlen; len -= rpmlen; } return 0; } /* * check validity of a router renumbering command packet * return 0 on success, 1 on failure */ static int rr_command_check(size_t len, struct icmp6_router_renum *rr, struct in6_addr *from, struct in6_addr *dst) { char ntopbuf[INET6_ADDRSTRLEN]; /* omit rr minimal length check. hope kernel have done it. */ /* rr_command length check */ if (len < (sizeof(struct icmp6_router_renum) + sizeof(struct rr_pco_match))) { syslog(LOG_ERR, "<%s> rr_command len %zd is too short", __func__, len); return 1; } /* destination check. only for multicast. omit unicast check. */ if (IN6_IS_ADDR_MULTICAST(dst) && !IN6_IS_ADDR_MC_LINKLOCAL(dst) && !IN6_IS_ADDR_MC_SITELOCAL(dst)) { syslog(LOG_ERR, "<%s> dst mcast addr %s is illegal", __func__, inet_ntop(AF_INET6, dst, ntopbuf, INET6_ADDRSTRLEN)); return 1; } /* seqnum and segnum check */ if (rro.rro_seqnum > rr->rr_seqnum) { syslog(LOG_WARNING, "<%s> rcvd old seqnum %d from %s", __func__, (uint32_t)ntohl(rr->rr_seqnum), inet_ntop(AF_INET6, from, ntopbuf, INET6_ADDRSTRLEN)); return 1; } if (rro.rro_seqnum == rr->rr_seqnum && (rr->rr_flags & ICMP6_RR_FLAGS_TEST) == 0 && RR_ISSET_SEGNUM(rro.rro_segnum_bits, rr->rr_segnum)) { if ((rr->rr_flags & ICMP6_RR_FLAGS_REQRESULT) != 0) syslog(LOG_WARNING, "<%s> rcvd duped segnum %d from %s", __func__, rr->rr_segnum, inet_ntop(AF_INET6, from, ntopbuf, INET6_ADDRSTRLEN)); return 0; } /* update seqnum */ if (rro.rro_seqnum != rr->rr_seqnum) { /* then must be "<" */ /* init rro_segnum_bits */ memset(rro.rro_segnum_bits, 0, sizeof(rro.rro_segnum_bits)); } rro.rro_seqnum = rr->rr_seqnum; return 0; } static void rr_command_input(int len, struct icmp6_router_renum *rr, struct in6_addr *from, struct in6_addr *dst) { /* rr_command validity check */ if (rr_command_check(len, rr, from, dst)) goto failed; if ((rr->rr_flags & (ICMP6_RR_FLAGS_TEST|ICMP6_RR_FLAGS_REQRESULT)) == ICMP6_RR_FLAGS_TEST) return; /* do router renumbering */ if (do_rr(len, rr)) { goto failed; } /* update segnum */ RR_SET_SEGNUM(rro.rro_segnum_bits, rr->rr_segnum); return; failed: syslog(LOG_ERR, "<%s> received RR was invalid", __func__); return; } void rr_input(size_t len, struct icmp6_router_renum *rr, struct in6_pktinfo *pi, struct sockaddr_in6 *from, struct in6_addr *dst) { char ntopbuf[2][INET6_ADDRSTRLEN], ifnamebuf[IFNAMSIZ]; syslog(LOG_DEBUG, "<%s> RR received from %s to %s on %s", __func__, inet_ntop(AF_INET6, &from->sin6_addr, ntopbuf[0], INET6_ADDRSTRLEN), inet_ntop(AF_INET6, &dst, ntopbuf[1], INET6_ADDRSTRLEN), if_indextoname(pi->ipi6_ifindex, ifnamebuf)); /* packet validation based on Section 4.1 of RFC2894 */ if (len < sizeof(struct icmp6_router_renum)) { syslog(LOG_NOTICE, "<%s>: RR short message (size %zd) from %s to %s on %s", __func__, len, inet_ntop(AF_INET6, &from->sin6_addr, ntopbuf[0], INET6_ADDRSTRLEN), inet_ntop(AF_INET6, &dst, ntopbuf[1], INET6_ADDRSTRLEN), if_indextoname(pi->ipi6_ifindex, ifnamebuf)); return; } /* * If the IPv6 destination address is neither an All Routers multicast * address [AARCH] nor one of the receiving router's unicast addresses, * the message MUST be discarded and SHOULD be logged to network * management. * We rely on the kernel input routine for unicast addresses, and thus * check multicast destinations only. */ if (IN6_IS_ADDR_MULTICAST(&pi->ipi6_addr) && !IN6_ARE_ADDR_EQUAL(&sin6_sitelocal_allrouters.sin6_addr, &pi->ipi6_addr)) { syslog(LOG_NOTICE, "<%s>: RR message with invalid destination (%s) " "from %s on %s", __func__, inet_ntop(AF_INET6, &dst, ntopbuf[0], INET6_ADDRSTRLEN), inet_ntop(AF_INET6, &from->sin6_addr, ntopbuf[1], INET6_ADDRSTRLEN), if_indextoname(pi->ipi6_ifindex, ifnamebuf)); return; } rr_rcvifindex = pi->ipi6_ifindex; switch (rr->rr_code) { case ICMP6_ROUTER_RENUMBERING_COMMAND: rr_command_input(len, rr, &from->sin6_addr, dst); /* TODO: send reply msg */ break; case ICMP6_ROUTER_RENUMBERING_RESULT: /* RESULT will be processed by rrenumd */ break; case ICMP6_ROUTER_RENUMBERING_SEQNUM_RESET: /* TODO: sequence number reset */ break; default: syslog(LOG_ERR, "<%s> received unknown code %d", __func__, rr->rr_code); break; } return; }