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IABSD.fr/src/sys/netinet6/in6_ifattach.c
claudio
- sys/netinet6/in6_ifattach.c
-
/* $OpenBSD: in6_ifattach.c,v 1.121 2022/11/15 18:42:46 claudio Exp $ */ /* $KAME: in6_ifattach.c,v 1.124 2001/07/18 08:32:51 jinmei 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 <sys/param.h> #include <sys/systm.h> #include <sys/socket.h> #include <sys/sockio.h> #include <sys/kernel.h> #include <sys/syslog.h> #include <crypto/sha2.h> #include <net/if.h> #include <net/if_var.h> #include <net/if_dl.h> #include <net/if_types.h> #include <net/route.h> #include <netinet/in.h> #include <netinet6/in6_var.h> #include <netinet/ip6.h> #include <netinet6/ip6_var.h> #include <netinet6/in6_ifattach.h> #include <netinet6/nd6.h> #ifdef MROUTING #include <netinet6/ip6_mroute.h> #endif void in6_get_rand_ifid(struct ifnet *, struct in6_addr *); int in6_get_hw_ifid(struct ifnet *, struct in6_addr *); void in6_get_ifid(struct ifnet *, struct in6_addr *); int in6_ifattach_loopback(struct ifnet *); #define EUI64_GBIT 0x01 #define EUI64_UBIT 0x02 #define EUI64_TO_IFID(in6) do {(in6)->s6_addr[8] ^= EUI64_UBIT; } while (0) #define EUI64_GROUP(in6) ((in6)->s6_addr[8] & EUI64_GBIT) #define EUI64_INDIVIDUAL(in6) (!EUI64_GROUP(in6)) #define EUI64_LOCAL(in6) ((in6)->s6_addr[8] & EUI64_UBIT) #define EUI64_UNIVERSAL(in6) (!EUI64_LOCAL(in6)) #define IFID_LOCAL(in6) (!EUI64_LOCAL(in6)) #define IFID_UNIVERSAL(in6) (!EUI64_UNIVERSAL(in6)) /* * Generate a random interface identifier. * * in6 - upper 64bits are preserved */ void in6_get_rand_ifid(struct ifnet *ifp, struct in6_addr *in6) { arc4random_buf(&in6->s6_addr32[2], 8); /* make sure to set "u" bit to local, and "g" bit to individual. */ in6->s6_addr[8] &= ~EUI64_GBIT; /* g bit to "individual" */ in6->s6_addr[8] |= EUI64_UBIT; /* u bit to "local" */ /* convert EUI64 into IPv6 interface identifier */ EUI64_TO_IFID(in6); } /* * Get interface identifier for the specified interface. * * in6 - upper 64bits are preserved */ int in6_get_hw_ifid(struct ifnet *ifp, struct in6_addr *in6) { struct sockaddr_dl *sdl; char *addr; size_t addrlen; static u_int8_t allzero[8] = { 0, 0, 0, 0, 0, 0, 0, 0 }; static u_int8_t allone[8] = { 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff }; sdl = ifp->if_sadl; if (sdl == NULL || sdl->sdl_alen == 0) return -1; addr = LLADDR(sdl); addrlen = sdl->sdl_alen; switch (ifp->if_type) { case IFT_IEEE1394: case IFT_IEEE80211: /* IEEE1394 uses 16byte length address starting with EUI64 */ if (addrlen > 8) addrlen = 8; break; default: break; } /* get EUI64 */ switch (ifp->if_type) { /* IEEE802/EUI64 cases - what others? */ case IFT_ETHER: case IFT_CARP: case IFT_IEEE1394: case IFT_IEEE80211: /* look at IEEE802/EUI64 only */ if (addrlen != 8 && addrlen != 6) return -1; /* * check for invalid MAC address - on bsdi, we see it a lot * since wildboar configures all-zero MAC on pccard before * card insertion. */ if (bcmp(addr, allzero, addrlen) == 0) return -1; if (bcmp(addr, allone, addrlen) == 0) return -1; /* make EUI64 address */ if (addrlen == 8) memcpy(&in6->s6_addr[8], addr, 8); else if (addrlen == 6) { in6->s6_addr[8] = addr[0]; in6->s6_addr[9] = addr[1]; in6->s6_addr[10] = addr[2]; in6->s6_addr[11] = 0xff; in6->s6_addr[12] = 0xfe; in6->s6_addr[13] = addr[3]; in6->s6_addr[14] = addr[4]; in6->s6_addr[15] = addr[5]; } break; case IFT_GIF: /* * RFC2893 says: "SHOULD use IPv4 address as ifid source". * however, IPv4 address is not very suitable as unique * identifier source (can be renumbered). * we don't do this. */ return -1; default: return -1; } /* sanity check: g bit must not indicate "group" */ if (EUI64_GROUP(in6)) return -1; /* convert EUI64 into IPv6 interface identifier */ EUI64_TO_IFID(in6); /* * sanity check: ifid must not be all zero, avoid conflict with * subnet router anycast */ if ((in6->s6_addr[8] & ~(EUI64_GBIT | EUI64_UBIT)) == 0x00 && bcmp(&in6->s6_addr[9], allzero, 7) == 0) { return -1; } return 0; } /* * Get interface identifier for the specified interface. If it is not * available on ifp0, borrow interface identifier from other information * sources. */ void in6_get_ifid(struct ifnet *ifp0, struct in6_addr *in6) { struct ifnet *ifp; /* first, try to get it from the interface itself */ if (in6_get_hw_ifid(ifp0, in6) == 0) { nd6log((LOG_DEBUG, "%s: got interface identifier from itself\n", ifp0->if_xname)); goto success; } /* next, try to get it from some other hardware interface */ TAILQ_FOREACH(ifp, &ifnetlist, if_list) { if (ifp == ifp0) continue; if (in6_get_hw_ifid(ifp, in6) == 0) goto success; } /* last resort: get from random number source */ in6_get_rand_ifid(ifp, in6); nd6log((LOG_DEBUG, "%s: interface identifier generated by random number\n", ifp0->if_xname)); success: nd6log((LOG_INFO, "%s: ifid: %02x:%02x:%02x:%02x:%02x:%02x:%02x:%02x\n", ifp0->if_xname, in6->s6_addr[8], in6->s6_addr[9], in6->s6_addr[10], in6->s6_addr[11], in6->s6_addr[12], in6->s6_addr[13], in6->s6_addr[14], in6->s6_addr[15])); } /* * ifid - used as EUI64 if not NULL, overrides other EUI64 sources */ int in6_ifattach_linklocal(struct ifnet *ifp, struct in6_addr *ifid) { struct in6_aliasreq ifra; struct in6_ifaddr *ia6; int error, flags; NET_ASSERT_LOCKED(); /* * configure link-local address. */ bzero(&ifra, sizeof(ifra)); strlcpy(ifra.ifra_name, ifp->if_xname, sizeof(ifra.ifra_name)); ifra.ifra_addr.sin6_family = AF_INET6; ifra.ifra_addr.sin6_len = sizeof(struct sockaddr_in6); ifra.ifra_addr.sin6_addr.s6_addr16[0] = htons(0xfe80); ifra.ifra_addr.sin6_addr.s6_addr16[1] = htons(ifp->if_index); ifra.ifra_addr.sin6_addr.s6_addr32[1] = 0; if ((ifp->if_flags & IFF_LOOPBACK) != 0) { ifra.ifra_addr.sin6_addr.s6_addr32[2] = 0; ifra.ifra_addr.sin6_addr.s6_addr32[3] = htonl(1); } else if (ifid) { ifra.ifra_addr.sin6_addr = *ifid; ifra.ifra_addr.sin6_addr.s6_addr16[0] = htons(0xfe80); ifra.ifra_addr.sin6_addr.s6_addr16[1] = htons(ifp->if_index); ifra.ifra_addr.sin6_addr.s6_addr32[1] = 0; ifra.ifra_addr.sin6_addr.s6_addr[8] &= ~EUI64_GBIT; ifra.ifra_addr.sin6_addr.s6_addr[8] |= EUI64_UBIT; } else in6_get_ifid(ifp, &ifra.ifra_addr.sin6_addr); ifra.ifra_prefixmask.sin6_len = sizeof(struct sockaddr_in6); ifra.ifra_prefixmask.sin6_family = AF_INET6; ifra.ifra_prefixmask.sin6_addr = in6mask64; /* link-local addresses should NEVER expire. */ ifra.ifra_lifetime.ia6t_vltime = ND6_INFINITE_LIFETIME; ifra.ifra_lifetime.ia6t_pltime = ND6_INFINITE_LIFETIME; /* * XXX: Some P2P interfaces seem not to send packets just after * becoming up, so we skip p2p interfaces for safety. */ if (in6if_do_dad(ifp) && ((ifp->if_flags & IFF_POINTOPOINT) == 0)) ifra.ifra_flags |= IN6_IFF_TENTATIVE; error = in6_update_ifa(ifp, &ifra, in6ifa_ifpforlinklocal(ifp, 0)); if (error != 0) return (error); ia6 = in6ifa_ifpforlinklocal(ifp, 0); /* Perform DAD, if needed. */ if (ia6->ia6_flags & IN6_IFF_TENTATIVE) nd6_dad_start(&ia6->ia_ifa); if (ifp->if_flags & IFF_LOOPBACK) { if_addrhooks_run(ifp); return (0); /* No need to install a connected route. */ } flags = RTF_CONNECTED | RTF_MPATH; if ((ifp->if_flags & IFF_POINTOPOINT) == 0) flags |= RTF_CLONING; error = rt_ifa_add(&ia6->ia_ifa, flags, ia6->ia_ifa.ifa_addr, ifp->if_rdomain); if (error) { in6_purgeaddr(&ia6->ia_ifa); return (error); } if_addrhooks_run(ifp); return (0); } int in6_ifattach_loopback(struct ifnet *ifp) { struct in6_addr in6 = in6addr_loopback; struct in6_aliasreq ifra; KASSERT(ifp->if_flags & IFF_LOOPBACK); if (in6ifa_ifpwithaddr(ifp, &in6) != NULL) return (0); bzero(&ifra, sizeof(ifra)); strlcpy(ifra.ifra_name, ifp->if_xname, sizeof(ifra.ifra_name)); ifra.ifra_prefixmask.sin6_len = sizeof(struct sockaddr_in6); ifra.ifra_prefixmask.sin6_family = AF_INET6; ifra.ifra_prefixmask.sin6_addr = in6mask128; /* * Always initialize ia_dstaddr (= broadcast address) to loopback * address. Follows IPv4 practice - see in_ifinit(). */ ifra.ifra_dstaddr.sin6_len = sizeof(struct sockaddr_in6); ifra.ifra_dstaddr.sin6_family = AF_INET6; ifra.ifra_dstaddr.sin6_addr = in6addr_loopback; ifra.ifra_addr.sin6_len = sizeof(struct sockaddr_in6); ifra.ifra_addr.sin6_family = AF_INET6; ifra.ifra_addr.sin6_addr = in6addr_loopback; /* the loopback address should NEVER expire. */ ifra.ifra_lifetime.ia6t_vltime = ND6_INFINITE_LIFETIME; ifra.ifra_lifetime.ia6t_pltime = ND6_INFINITE_LIFETIME; /* * We are sure that this is a newly assigned address, so we can set * NULL to the 3rd arg. */ return (in6_update_ifa(ifp, &ifra, NULL)); } /* * XXX multiple loopback interface needs more care. for instance, * nodelocal address needs to be configured onto only one of them. * XXX multiple link-local address case */ int in6_ifattach(struct ifnet *ifp) { /* some of the interfaces are inherently not IPv6 capable */ switch (ifp->if_type) { case IFT_BRIDGE: case IFT_ENC: case IFT_PFLOG: case IFT_PFSYNC: return (0); } /* * if link mtu is too small, don't try to configure IPv6. * remember there could be some link-layer that has special * fragmentation logic. */ if (ifp->if_mtu < IPV6_MMTU) return (EINVAL); if (nd6_need_cache(ifp) && (ifp->if_flags & IFF_MULTICAST) == 0) return (EINVAL); /* * Assign loopback address if this lo(4) interface is the * default for its rdomain. */ if ((ifp->if_flags & IFF_LOOPBACK) && (ifp->if_index == rtable_loindex(ifp->if_rdomain))) { int error; error = in6_ifattach_loopback(ifp); if (error) return (error); } switch (ifp->if_type) { case IFT_WIREGUARD: return (0); } /* Assign a link-local address, if there's none. */ if (in6ifa_ifpforlinklocal(ifp, 0) == NULL) { if (in6_ifattach_linklocal(ifp, NULL) != 0) { /* failed to assign linklocal address. bark? */ } } return (0); } /* * NOTE: in6_ifdetach() does not support loopback if at this moment. */ void in6_ifdetach(struct ifnet *ifp) { struct ifaddr *ifa, *next; struct rtentry *rt; struct sockaddr_in6 sin6; #ifdef MROUTING /* remove ip6_mrouter stuff */ ip6_mrouter_detach(ifp); #endif /* nuke any of IPv6 addresses we have */ TAILQ_FOREACH_SAFE(ifa, &ifp->if_addrlist, ifa_list, next) { if (ifa->ifa_addr->sa_family != AF_INET6) continue; in6_purgeaddr(ifa); if_addrhooks_run(ifp); } /* * Remove neighbor management table. Must be called after * purging addresses. */ nd6_purge(ifp); /* remove route to interface local allnodes multicast (ff01::1) */ bzero(&sin6, sizeof(sin6)); sin6.sin6_len = sizeof(struct sockaddr_in6); sin6.sin6_family = AF_INET6; sin6.sin6_addr = in6addr_intfacelocal_allnodes; sin6.sin6_addr.s6_addr16[1] = htons(ifp->if_index); rt = rtalloc(sin6tosa(&sin6), 0, ifp->if_rdomain); if (rt && rt->rt_ifidx == ifp->if_index) { rtdeletemsg(rt, ifp, ifp->if_rdomain); rtfree(rt); } /* remove route to link-local allnodes multicast (ff02::1) */ bzero(&sin6, sizeof(sin6)); sin6.sin6_len = sizeof(struct sockaddr_in6); sin6.sin6_family = AF_INET6; sin6.sin6_addr = in6addr_linklocal_allnodes; sin6.sin6_addr.s6_addr16[1] = htons(ifp->if_index); rt = rtalloc(sin6tosa(&sin6), 0, ifp->if_rdomain); if (rt && rt->rt_ifidx == ifp->if_index) { rtdeletemsg(rt, ifp, ifp->if_rdomain); rtfree(rt); } if (ifp->if_xflags & (IFXF_AUTOCONF6 | IFXF_AUTOCONF6TEMP)) ifp->if_xflags &= ~(IFXF_AUTOCONF6 | IFXF_AUTOCONF6TEMP); }