1 /* $NetBSD: util.c,v 1.11 2005/06/07 22:21:57 lukem Exp $ */ 2 3 /*- 4 * Copyright (c) 2000 The NetBSD Foundation, Inc. 5 * All rights reserved. 6 * 7 * This code is derived from software contributed to The NetBSD Foundation 8 * by Frank van der Linden. 9 * 10 * Redistribution and use in source and binary forms, with or without 11 * modification, are permitted provided that the following conditions 12 * are met: 13 * 1. Redistributions of source code must retain the above copyright 14 * notice, this list of conditions and the following disclaimer. 15 * 2. Redistributions in binary form must reproduce the above copyright 16 * notice, this list of conditions and the following disclaimer in the 17 * documentation and/or other materials provided with the distribution. 18 * 3. All advertising materials mentioning features or use of this software 19 * must display the following acknowledgement: 20 * This product includes software developed by the NetBSD 21 * Foundation, Inc. and its contributors. 22 * 4. Neither the name of The NetBSD Foundation nor the names of its 23 * contributors may be used to endorse or promote products derived 24 * from this software without specific prior written permission. 25 * 26 * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS 27 * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED 28 * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR 29 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS 30 * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR 31 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF 32 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS 33 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN 34 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) 35 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE 36 * POSSIBILITY OF SUCH DAMAGE. 37 */ 38 39 #include <sys/types.h> 40 #include <sys/socket.h> 41 #include <sys/queue.h> 42 #include <net/if.h> 43 #include <netinet/in.h> 44 #include <ifaddrs.h> 45 #include <poll.h> 46 #include <rpc/rpc.h> 47 #include <errno.h> 48 #include <stdlib.h> 49 #include <string.h> 50 #include <unistd.h> 51 #include <netdb.h> 52 #include <netconfig.h> 53 #include <stdio.h> 54 #include <arpa/inet.h> 55 56 #include "rpcbind.h" 57 58 static struct sockaddr_in *local_in4; 59 #ifdef INET6 60 static struct sockaddr_in6 *local_in6; 61 #endif 62 63 static int bitmaskcmp __P((void *, void *, void *, int)); 64 #ifdef INET6 65 static void in6_fillscopeid __P((struct sockaddr_in6 *)); 66 #endif 67 68 /* 69 * For all bits set in "mask", compare the corresponding bits in 70 * "dst" and "src", and see if they match. 71 */ 72 static int 73 bitmaskcmp(void *dst, void *src, void *mask, int bytelen) 74 { 75 int i, j; 76 u_int8_t *p1 = dst, *p2 = src, *netmask = mask; 77 u_int8_t bitmask; 78 79 for (i = 0; i < bytelen; i++) { 80 for (j = 0; j < 8; j++) { 81 bitmask = 1 << j; 82 if (!(netmask[i] & bitmask)) 83 continue; 84 if ((p1[i] & bitmask) != (p2[i] & bitmask)) 85 return 1; 86 } 87 } 88 89 return 0; 90 } 91 92 /* 93 * Taken from ifconfig.c 94 */ 95 #ifdef INET6 96 static void 97 in6_fillscopeid(struct sockaddr_in6 *sin6) 98 { 99 if (IN6_IS_ADDR_LINKLOCAL(&sin6->sin6_addr)) { 100 sin6->sin6_scope_id = 101 ntohs(*(u_int16_t *)&sin6->sin6_addr.s6_addr[2]); 102 sin6->sin6_addr.s6_addr[2] = sin6->sin6_addr.s6_addr[3] = 0; 103 } 104 } 105 #endif 106 107 char * 108 addrmerge(struct netbuf *caller, char *serv_uaddr, char *clnt_uaddr, 109 char *netid) 110 { 111 struct ifaddrs *ifap, *ifp, *bestif; 112 #ifdef INET6 113 struct sockaddr_in6 *servsin6, *sin6mask, *clntsin6, *ifsin6, *realsin6; 114 struct sockaddr_in6 *newsin6; 115 #endif 116 struct sockaddr_in *servsin, *sinmask, *clntsin, *newsin, *ifsin; 117 struct netbuf *serv_nbp, *clnt_nbp = NULL, tbuf; 118 struct sockaddr *serv_sa; 119 struct sockaddr *clnt_sa; 120 struct sockaddr_storage ss; 121 struct netconfig *nconf; 122 struct sockaddr *clnt = caller->buf; 123 char *ret = NULL; 124 125 #ifdef INET6 126 servsin6 = ifsin6 = newsin6 = NULL; /* XXXGCC -Wuninitialized */ 127 #endif 128 servsin = newsin = NULL; /* XXXGCC -Wuninitialized */ 129 130 #ifdef ND_DEBUG 131 if (debugging) 132 fprintf(stderr, "addrmerge(caller, %s, %s, %s\n", serv_uaddr, 133 clnt_uaddr, netid); 134 #endif 135 nconf = getnetconfigent(netid); 136 if (nconf == NULL) 137 return NULL; 138 139 /* 140 * Local merge, just return a duplicate. 141 */ 142 if (clnt_uaddr != NULL && strncmp(clnt_uaddr, "0.0.0.0.", 8) == 0) 143 return strdup(clnt_uaddr); 144 145 serv_nbp = uaddr2taddr(nconf, serv_uaddr); 146 if (serv_nbp == NULL) 147 return NULL; 148 149 serv_sa = (struct sockaddr *)serv_nbp->buf; 150 if (clnt_uaddr != NULL) { 151 clnt_nbp = uaddr2taddr(nconf, clnt_uaddr); 152 if (clnt_nbp == NULL) { 153 free(serv_nbp); 154 return NULL; 155 } 156 clnt_sa = (struct sockaddr *)clnt_nbp->buf; 157 if (clnt_sa->sa_family == AF_LOCAL) { 158 free(serv_nbp); 159 free(clnt_nbp); 160 free(clnt_sa); 161 return strdup(serv_uaddr); 162 } 163 } else { 164 clnt_sa = (struct sockaddr *) 165 malloc(sizeof (struct sockaddr_storage)); 166 memcpy(clnt_sa, clnt, clnt->sa_len); 167 } 168 169 if (getifaddrs(&ifp) < 0) { 170 free(serv_nbp); 171 free(clnt_sa); 172 if (clnt_nbp != NULL) 173 free(clnt_nbp); 174 return 0; 175 } 176 177 /* 178 * Loop through all interfaces. For each interface, see if the 179 * network portion of its address is equal to that of the client. 180 * If so, we have found the interface that we want to use. 181 */ 182 for (ifap = ifp; ifap != NULL; ifap = ifap->ifa_next) { 183 if (ifap->ifa_addr->sa_family != clnt->sa_family || 184 !(ifap->ifa_flags & IFF_UP)) 185 continue; 186 187 switch (clnt->sa_family) { 188 case AF_INET: 189 /* 190 * realsin: address that recvfrom gave us. 191 * ifsin: address of interface being examined. 192 * clntsin: address that client want us to contact 193 * it on 194 * servsin: local address of RPC service. 195 * sinmask: netmask of this interface 196 * newsin: initially a copy of clntsin, eventually 197 * the merged address 198 */ 199 servsin = (struct sockaddr_in *)serv_sa; 200 clntsin = (struct sockaddr_in *)clnt_sa; 201 sinmask = (struct sockaddr_in *)ifap->ifa_netmask; 202 newsin = (struct sockaddr_in *)&ss; 203 ifsin = (struct sockaddr_in *)ifap->ifa_addr; 204 if (!bitmaskcmp(&ifsin->sin_addr, &clntsin->sin_addr, 205 &sinmask->sin_addr, sizeof (struct in_addr))) { 206 goto found; 207 } 208 break; 209 #ifdef INET6 210 case AF_INET6: 211 /* 212 * realsin6: address that recvfrom gave us. 213 * ifsin6: address of interface being examined. 214 * clntsin6: address that client want us to contact 215 * it on 216 * servsin6: local address of RPC service. 217 * sin6mask: netmask of this interface 218 * newsin6: initially a copy of clntsin, eventually 219 * the merged address 220 * 221 * For v6 link local addresses, if the client contacted 222 * us via a link-local address, and wants us to reply 223 * to one, use the scope id to see which one. 224 */ 225 realsin6 = (struct sockaddr_in6 *)clnt; 226 ifsin6 = (struct sockaddr_in6 *)ifap->ifa_addr; 227 in6_fillscopeid(ifsin6); 228 clntsin6 = (struct sockaddr_in6 *)clnt_sa; 229 servsin6 = (struct sockaddr_in6 *)serv_sa; 230 sin6mask = (struct sockaddr_in6 *)ifap->ifa_netmask; 231 newsin6 = (struct sockaddr_in6 *)&ss; 232 if (IN6_IS_ADDR_LINKLOCAL(&ifsin6->sin6_addr) && 233 IN6_IS_ADDR_LINKLOCAL(&realsin6->sin6_addr) && 234 IN6_IS_ADDR_LINKLOCAL(&clntsin6->sin6_addr)) { 235 if (ifsin6->sin6_scope_id != 236 realsin6->sin6_scope_id) 237 continue; 238 goto found; 239 } 240 if (!bitmaskcmp(&ifsin6->sin6_addr, 241 &clntsin6->sin6_addr, &sin6mask->sin6_addr, 242 sizeof (struct in6_addr))) 243 goto found; 244 break; 245 #endif 246 default: 247 goto freeit; 248 } 249 } 250 /* 251 * Didn't find anything. Get the first possibly useful interface, 252 * preferring "normal" interfaces to point-to-point and loopback 253 * ones. 254 */ 255 bestif = NULL; 256 for (ifap = ifp; ifap != NULL; ifap = ifap->ifa_next) { 257 if (ifap->ifa_addr->sa_family != clnt->sa_family || 258 !(ifap->ifa_flags & IFF_UP)) 259 continue; 260 if (!(ifap->ifa_flags & IFF_LOOPBACK) && 261 !(ifap->ifa_flags & IFF_POINTOPOINT)) { 262 bestif = ifap; 263 break; 264 } 265 if (bestif == NULL) 266 bestif = ifap; 267 else if ((bestif->ifa_flags & IFF_LOOPBACK) && 268 !(ifap->ifa_flags & IFF_LOOPBACK)) 269 bestif = ifap; 270 } 271 ifap = bestif; 272 found: 273 switch (clnt->sa_family) { 274 case AF_INET: 275 memcpy(newsin, ifap->ifa_addr, clnt_sa->sa_len); 276 newsin->sin_port = servsin->sin_port; 277 tbuf.len = clnt_sa->sa_len; 278 tbuf.maxlen = sizeof (struct sockaddr_storage); 279 tbuf.buf = newsin; 280 break; 281 #ifdef INET6 282 case AF_INET6: 283 memcpy(newsin6, ifsin6, clnt_sa->sa_len); 284 newsin6->sin6_port = servsin6->sin6_port; 285 tbuf.maxlen = sizeof (struct sockaddr_storage); 286 tbuf.len = clnt_sa->sa_len; 287 tbuf.buf = newsin6; 288 break; 289 #endif 290 default: 291 goto freeit; 292 } 293 if (ifap != NULL) 294 ret = taddr2uaddr(nconf, &tbuf); 295 freeit: 296 freenetconfigent(nconf); 297 free(serv_sa); 298 free(serv_nbp); 299 if (clnt_sa != NULL) 300 free(clnt_sa); 301 if (clnt_nbp != NULL) 302 free(clnt_nbp); 303 freeifaddrs(ifp); 304 305 #ifdef ND_DEBUG 306 if (debugging) 307 fprintf(stderr, "addrmerge: returning %s\n", ret); 308 #endif 309 return ret; 310 } 311 312 void 313 network_init() 314 { 315 #ifdef INET6 316 struct ifaddrs *ifap, *ifp; 317 struct ipv6_mreq mreq6; 318 int ifindex, s; 319 #endif 320 int ecode; 321 struct addrinfo hints, *res; 322 323 memset(&hints, 0, sizeof hints); 324 hints.ai_family = AF_INET; 325 if ((ecode = getaddrinfo(NULL, "sunrpc", &hints, &res))) { 326 if (debugging) 327 fprintf(stderr, "can't get local ip4 address: %s\n", 328 gai_strerror(ecode)); 329 } else { 330 local_in4 = (struct sockaddr_in *)malloc(sizeof *local_in4); 331 if (local_in4 == NULL) { 332 if (debugging) 333 fprintf(stderr, "can't alloc local ip4 addr\n"); 334 } 335 memcpy(local_in4, res->ai_addr, sizeof *local_in4); 336 } 337 338 #ifdef INET6 339 hints.ai_family = AF_INET6; 340 if ((ecode = getaddrinfo(NULL, "sunrpc", &hints, &res))) { 341 if (debugging) 342 fprintf(stderr, "can't get local ip6 address: %s\n", 343 gai_strerror(ecode)); 344 } else { 345 local_in6 = (struct sockaddr_in6 *)malloc(sizeof *local_in6); 346 if (local_in6 == NULL) { 347 if (debugging) 348 fprintf(stderr, "can't alloc local ip6 addr\n"); 349 } 350 memcpy(local_in6, res->ai_addr, sizeof *local_in6); 351 } 352 353 /* 354 * Now join the RPC ipv6 multicast group on all interfaces. 355 */ 356 if (getifaddrs(&ifp) < 0) 357 return; 358 359 mreq6.ipv6mr_interface = 0; 360 inet_pton(AF_INET6, RPCB_MULTICAST_ADDR, &mreq6.ipv6mr_multiaddr); 361 362 s = socket(AF_INET6, SOCK_DGRAM, IPPROTO_UDP); 363 364 /* 365 * Loop through all interfaces. For each interface, see if the 366 * network portion of its address is equal to that of the client. 367 * If so, we have found the interface that we want to use. 368 */ 369 for (ifap = ifp; ifap != NULL; ifap = ifap->ifa_next) { 370 if (ifap->ifa_addr->sa_family != AF_INET6 || 371 !(ifap->ifa_flags & IFF_MULTICAST)) 372 continue; 373 ifindex = if_nametoindex(ifap->ifa_name); 374 if (ifindex == mreq6.ipv6mr_interface) 375 /* 376 * Already did this one. 377 */ 378 continue; 379 mreq6.ipv6mr_interface = ifindex; 380 if (setsockopt(s, IPPROTO_IPV6, IPV6_JOIN_GROUP, &mreq6, 381 sizeof mreq6) < 0) 382 if (debugging) 383 perror("setsockopt v6 multicast"); 384 } 385 #endif 386 387 /* close(s); */ 388 } 389 390 struct sockaddr * 391 local_sa(int af) 392 { 393 switch (af) { 394 case AF_INET: 395 return (struct sockaddr *)local_in4; 396 #ifdef INET6 397 case AF_INET6: 398 return (struct sockaddr *)local_in6; 399 #endif 400 default: 401 return NULL; 402 } 403 } 404