/* * $NetBSD: util.c,v 1.4 2000/08/03 00:04:30 fvdl Exp $ * $FreeBSD$ */ /*- * SPDX-License-Identifier: BSD-2-Clause-NetBSD * * Copyright (c) 2000 The NetBSD Foundation, Inc. * All rights reserved. * * This code is derived from software contributed to The NetBSD Foundation * by Frank van der Linden. * * 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. * * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. 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 FOUNDATION 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 "rpcbind.h" static struct sockaddr_in *local_in4; #ifdef INET6 static struct sockaddr_in6 *local_in6; #endif static int bitmaskcmp(struct sockaddr *, struct sockaddr *, struct sockaddr *); /* * For all bits set in "mask", compare the corresponding bits in * "dst" and "src", and see if they match. Returns 0 if the addresses * match. */ static int bitmaskcmp(struct sockaddr *dst, struct sockaddr *src, struct sockaddr *mask) { int i; u_int8_t *p1, *p2, *netmask; int bytelen; if (dst->sa_family != src->sa_family || dst->sa_family != mask->sa_family) return (1); switch (dst->sa_family) { case AF_INET: p1 = (uint8_t*) &SA2SINADDR(dst); p2 = (uint8_t*) &SA2SINADDR(src); netmask = (uint8_t*) &SA2SINADDR(mask); bytelen = sizeof(struct in_addr); break; #ifdef INET6 case AF_INET6: p1 = (uint8_t*) &SA2SIN6ADDR(dst); p2 = (uint8_t*) &SA2SIN6ADDR(src); netmask = (uint8_t*) &SA2SIN6ADDR(mask); bytelen = sizeof(struct in6_addr); break; #endif default: return (1); } for (i = 0; i < bytelen; i++) if ((p1[i] & netmask[i]) != (p2[i] & netmask[i])) return (1); return (0); } /* * Find a server address that can be used by `caller' to contact * the local service specified by `serv_uaddr'. If `clnt_uaddr' is * non-NULL, it is used instead of `caller' as a hint suggesting * the best address (e.g. the `r_addr' field of an rpc, which * contains the rpcbind server address that the caller used). * * Returns the best server address as a malloc'd "universal address" * string which should be freed by the caller. On error, returns NULL. */ char * addrmerge(struct netbuf *caller, const char *serv_uaddr, const char *clnt_uaddr, const char *netid) { struct ifaddrs *ifap, *ifp = NULL, *bestif; struct netbuf *serv_nbp = NULL, *hint_nbp = NULL, tbuf; struct sockaddr *caller_sa, *hint_sa, *ifsa, *ifmasksa, *serv_sa; struct sockaddr_storage ss; struct netconfig *nconf; char *caller_uaddr = NULL; #ifdef ND_DEBUG const char *hint_uaddr = NULL; #endif char *ret = NULL; int bestif_goodness; #ifdef ND_DEBUG if (debugging) fprintf(stderr, "addrmerge(caller, %s, %s, %s\n", serv_uaddr, clnt_uaddr == NULL ? "NULL" : clnt_uaddr, netid); #endif caller_sa = caller->buf; if ((nconf = rpcbind_get_conf(netid)) == NULL) goto freeit; if ((caller_uaddr = taddr2uaddr(nconf, caller)) == NULL) goto freeit; /* * Use `clnt_uaddr' as the hint if non-NULL, but ignore it if its * address family is different from that of the caller. */ hint_sa = NULL; if (clnt_uaddr != NULL) { #ifdef ND_DEBUG hint_uaddr = clnt_uaddr; #endif if ((hint_nbp = uaddr2taddr(nconf, clnt_uaddr)) == NULL) goto freeit; hint_sa = hint_nbp->buf; } if (hint_sa == NULL || hint_sa->sa_family != caller_sa->sa_family) { #ifdef ND_DEBUG hint_uaddr = caller_uaddr; #endif hint_sa = caller->buf; } #ifdef ND_DEBUG if (debugging) fprintf(stderr, "addrmerge: hint %s\n", hint_uaddr); #endif /* Local caller, just return the server address. */ if (strncmp(caller_uaddr, "0.0.0.0.", 8) == 0 || strncmp(caller_uaddr, "::.", 3) == 0 || caller_uaddr[0] == '/') { ret = strdup(serv_uaddr); goto freeit; } if (getifaddrs(&ifp) < 0) goto freeit; /* * Loop through all interface addresses. We are listening to an address * if any of the following are true: * a) It's a loopback address * b) It was specified with the -h command line option * c) There were no -h command line options. * * Among addresses on which we are listening, choose in order of * preference an address that is: * * a) Equal to the hint * b) A link local address with the same scope ID as the client's * address, if the client's address is also link local * c) An address on the same subnet as the client's address * d) A non-localhost, non-p2p address * e) Any usable address */ bestif = NULL; bestif_goodness = 0; for (ifap = ifp; ifap != NULL; ifap = ifap->ifa_next) { ifsa = ifap->ifa_addr; ifmasksa = ifap->ifa_netmask; /* Skip addresses where we don't listen */ if (ifsa == NULL || ifsa->sa_family != hint_sa->sa_family || !(ifap->ifa_flags & IFF_UP)) continue; if (!(ifap->ifa_flags & IFF_LOOPBACK) && !listen_addr(ifsa)) continue; if ((hint_sa->sa_family == AF_INET) && ((((struct sockaddr_in*)hint_sa)->sin_addr.s_addr == ((struct sockaddr_in*)ifsa)->sin_addr.s_addr))) { const int goodness = 4; bestif_goodness = goodness; bestif = ifap; goto found; } #ifdef INET6 if ((hint_sa->sa_family == AF_INET6) && (0 == memcmp(&((struct sockaddr_in6*)hint_sa)->sin6_addr, &((struct sockaddr_in6*)ifsa)->sin6_addr, sizeof(struct in6_addr))) && (((struct sockaddr_in6*)hint_sa)->sin6_scope_id == (((struct sockaddr_in6*)ifsa)->sin6_scope_id))) { const int goodness = 4; bestif_goodness = goodness; bestif = ifap; goto found; } if (hint_sa->sa_family == AF_INET6) { /* * For v6 link local addresses, if the caller is on * a link-local address then use the scope id to see * which one. */ if (IN6_IS_ADDR_LINKLOCAL(&SA2SIN6ADDR(ifsa)) && IN6_IS_ADDR_LINKLOCAL(&SA2SIN6ADDR(caller_sa)) && IN6_IS_ADDR_LINKLOCAL(&SA2SIN6ADDR(hint_sa))) { if (SA2SIN6(ifsa)->sin6_scope_id == SA2SIN6(caller_sa)->sin6_scope_id) { const int goodness = 3; if (bestif_goodness < goodness) { bestif = ifap; bestif_goodness = goodness; } } } } #endif /* INET6 */ if (0 == bitmaskcmp(hint_sa, ifsa, ifmasksa)) { const int goodness = 2; if (bestif_goodness < goodness) { bestif = ifap; bestif_goodness = goodness; } } if (!(ifap->ifa_flags & (IFF_LOOPBACK | IFF_POINTOPOINT))) { const int goodness = 1; if (bestif_goodness < goodness) { bestif = ifap; bestif_goodness = goodness; } } if (bestif == NULL) bestif = ifap; } if (bestif == NULL) goto freeit; found: /* * Construct the new address using the address from * `bestif', and the port number from `serv_uaddr'. */ serv_nbp = uaddr2taddr(nconf, serv_uaddr); if (serv_nbp == NULL) goto freeit; serv_sa = serv_nbp->buf; memcpy(&ss, bestif->ifa_addr, bestif->ifa_addr->sa_len); switch (ss.ss_family) { case AF_INET: SA2SIN(&ss)->sin_port = SA2SIN(serv_sa)->sin_port; break; #ifdef INET6 case AF_INET6: SA2SIN6(&ss)->sin6_port = SA2SIN6(serv_sa)->sin6_port; break; #endif } tbuf.len = ss.ss_len; tbuf.maxlen = sizeof(ss); tbuf.buf = &ss; ret = taddr2uaddr(nconf, &tbuf); freeit: free(caller_uaddr); if (hint_nbp != NULL) { free(hint_nbp->buf); free(hint_nbp); } if (serv_nbp != NULL) { free(serv_nbp->buf); free(serv_nbp); } if (ifp != NULL) freeifaddrs(ifp); #ifdef ND_DEBUG if (debugging) fprintf(stderr, "addrmerge: returning %s\n", ret); #endif return ret; } void network_init(void) { #ifdef INET6 struct ifaddrs *ifap, *ifp; struct ipv6_mreq mreq6; unsigned int ifindex; int s; #endif int ecode; struct addrinfo hints, *res; memset(&hints, 0, sizeof hints); hints.ai_family = AF_INET; if ((ecode = getaddrinfo(NULL, "sunrpc", &hints, &res))) { if (debugging) fprintf(stderr, "can't get local ip4 address: %s\n", gai_strerror(ecode)); } else { local_in4 = (struct sockaddr_in *)malloc(sizeof *local_in4); if (local_in4 == NULL) { if (debugging) fprintf(stderr, "can't alloc local ip4 addr\n"); exit(1); } memcpy(local_in4, res->ai_addr, sizeof *local_in4); freeaddrinfo(res); } #ifdef INET6 hints.ai_family = AF_INET6; if ((ecode = getaddrinfo(NULL, "sunrpc", &hints, &res))) { if (debugging) fprintf(stderr, "can't get local ip6 address: %s\n", gai_strerror(ecode)); } else { local_in6 = (struct sockaddr_in6 *)malloc(sizeof *local_in6); if (local_in6 == NULL) { if (debugging) fprintf(stderr, "can't alloc local ip6 addr\n"); exit(1); } memcpy(local_in6, res->ai_addr, sizeof *local_in6); freeaddrinfo(res); } /* * Now join the RPC ipv6 multicast group on all interfaces. */ if (getifaddrs(&ifp) < 0) return; mreq6.ipv6mr_interface = 0; inet_pton(AF_INET6, RPCB_MULTICAST_ADDR, &mreq6.ipv6mr_multiaddr); s = socket(AF_INET6, SOCK_DGRAM, IPPROTO_UDP); if (s == -1) { if (debugging) fprintf(stderr, "couldn't create ip6 socket"); goto done_inet6; } /* * Loop through all interfaces. For each IPv6 multicast-capable * interface, join the RPC multicast group on that interface. */ for (ifap = ifp; ifap != NULL; ifap = ifap->ifa_next) { if (ifap->ifa_addr->sa_family != AF_INET6 || !(ifap->ifa_flags & IFF_MULTICAST)) continue; ifindex = if_nametoindex(ifap->ifa_name); if (ifindex == mreq6.ipv6mr_interface) /* * Already did this one. */ continue; mreq6.ipv6mr_interface = ifindex; if (setsockopt(s, IPPROTO_IPV6, IPV6_JOIN_GROUP, &mreq6, sizeof mreq6) < 0) if (debugging) perror("setsockopt v6 multicast"); } done_inet6: freeifaddrs(ifp); #endif /* close(s); */ } struct sockaddr * local_sa(int af) { switch (af) { case AF_INET: return (struct sockaddr *)local_in4; #ifdef INET6 case AF_INET6: return (struct sockaddr *)local_in6; #endif default: return NULL; } }