1 /* $NetBSD: util.c,v 1.7 2001/04/30 00:36:08 fvdl 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 <sys/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 ND_DEBUG 126 if (debugging) 127 fprintf(stderr, "addrmerge(caller, %s, %s, %s\n", serv_uaddr, 128 clnt_uaddr, netid); 129 #endif 130 nconf = getnetconfigent(netid); 131 if (nconf == NULL) 132 return NULL; 133 134 /* 135 * Local merge, just return a duplicate. 136 */ 137 if (clnt_uaddr != NULL && strncmp(clnt_uaddr, "0.0.0.0.", 8) == 0) 138 return strdup(clnt_uaddr); 139 140 serv_nbp = uaddr2taddr(nconf, serv_uaddr); 141 if (serv_nbp == NULL) 142 return NULL; 143 144 serv_sa = (struct sockaddr *)serv_nbp->buf; 145 if (clnt_uaddr != NULL) { 146 clnt_nbp = uaddr2taddr(nconf, clnt_uaddr); 147 if (clnt_nbp == NULL) { 148 free(serv_nbp); 149 return NULL; 150 } 151 clnt_sa = (struct sockaddr *)clnt_nbp->buf; 152 if (clnt_sa->sa_family == AF_LOCAL) { 153 free(serv_nbp); 154 free(clnt_nbp); 155 free(clnt_sa); 156 return strdup(serv_uaddr); 157 } 158 } else { 159 clnt_sa = (struct sockaddr *) 160 malloc(sizeof (struct sockaddr_storage)); 161 memcpy(clnt_sa, clnt, clnt->sa_len); 162 } 163 164 if (getifaddrs(&ifp) < 0) { 165 free(serv_nbp); 166 free(clnt_sa); 167 if (clnt_nbp != NULL) 168 free(clnt_nbp); 169 return 0; 170 } 171 172 /* 173 * Loop through all interfaces. For each interface, see if the 174 * network portion of its address is equal to that of the client. 175 * If so, we have found the interface that we want to use. 176 */ 177 for (ifap = ifp; ifap != NULL; ifap = ifap->ifa_next) { 178 if (ifap->ifa_addr->sa_family != clnt->sa_family || 179 !(ifap->ifa_flags & IFF_UP)) 180 continue; 181 182 switch (clnt->sa_family) { 183 case AF_INET: 184 /* 185 * realsin: address that recvfrom gave us. 186 * ifsin: address of interface being examined. 187 * clntsin: address that client want us to contact 188 * it on 189 * servsin: local address of RPC service. 190 * sinmask: netmask of this interface 191 * newsin: initially a copy of clntsin, eventually 192 * the merged address 193 */ 194 servsin = (struct sockaddr_in *)serv_sa; 195 clntsin = (struct sockaddr_in *)clnt_sa; 196 sinmask = (struct sockaddr_in *)ifap->ifa_netmask; 197 newsin = (struct sockaddr_in *)&ss; 198 ifsin = (struct sockaddr_in *)ifap->ifa_addr; 199 if (!bitmaskcmp(&ifsin->sin_addr, &clntsin->sin_addr, 200 &sinmask->sin_addr, sizeof (struct in_addr))) { 201 goto found; 202 } 203 break; 204 #ifdef INET6 205 case AF_INET6: 206 /* 207 * realsin6: address that recvfrom gave us. 208 * ifsin6: address of interface being examined. 209 * clntsin6: address that client want us to contact 210 * it on 211 * servsin6: local address of RPC service. 212 * sin6mask: netmask of this interface 213 * newsin6: initially a copy of clntsin, eventually 214 * the merged address 215 * 216 * For v6 link local addresses, if the client contacted 217 * us via a link-local address, and wants us to reply 218 * to one, use the scope id to see which one. 219 */ 220 realsin6 = (struct sockaddr_in6 *)clnt; 221 ifsin6 = (struct sockaddr_in6 *)ifap->ifa_addr; 222 in6_fillscopeid(ifsin6); 223 clntsin6 = (struct sockaddr_in6 *)clnt_sa; 224 servsin6 = (struct sockaddr_in6 *)serv_sa; 225 sin6mask = (struct sockaddr_in6 *)ifap->ifa_netmask; 226 newsin6 = (struct sockaddr_in6 *)&ss; 227 if (IN6_IS_ADDR_LINKLOCAL(&ifsin6->sin6_addr) && 228 IN6_IS_ADDR_LINKLOCAL(&realsin6->sin6_addr) && 229 IN6_IS_ADDR_LINKLOCAL(&clntsin6->sin6_addr)) { 230 if (ifsin6->sin6_scope_id != 231 realsin6->sin6_scope_id) 232 continue; 233 goto found; 234 } 235 if (!bitmaskcmp(&ifsin6->sin6_addr, 236 &clntsin6->sin6_addr, &sin6mask->sin6_addr, 237 sizeof (struct in6_addr))) 238 goto found; 239 break; 240 #endif 241 default: 242 goto freeit; 243 } 244 } 245 /* 246 * Didn't find anything. Get the first possibly useful interface, 247 * preferring "normal" interfaces to point-to-point and loopback 248 * ones. 249 */ 250 bestif = NULL; 251 for (ifap = ifp; ifap != NULL; ifap = ifap->ifa_next) { 252 if (ifap->ifa_addr->sa_family != clnt->sa_family || 253 !(ifap->ifa_flags & IFF_UP)) 254 continue; 255 if (!(ifap->ifa_flags & IFF_LOOPBACK) && 256 !(ifap->ifa_flags & IFF_POINTOPOINT)) { 257 bestif = ifap; 258 break; 259 } 260 if (bestif == NULL) 261 bestif = ifap; 262 else if ((bestif->ifa_flags & IFF_LOOPBACK) && 263 !(ifap->ifa_flags & IFF_LOOPBACK)) 264 bestif = ifap; 265 } 266 ifap = bestif; 267 found: 268 switch (clnt->sa_family) { 269 case AF_INET: 270 memcpy(newsin, ifap->ifa_addr, clnt_sa->sa_len); 271 newsin->sin_port = servsin->sin_port; 272 tbuf.len = clnt_sa->sa_len; 273 tbuf.maxlen = sizeof (struct sockaddr_storage); 274 tbuf.buf = newsin; 275 break; 276 #ifdef INET6 277 case AF_INET6: 278 memcpy(newsin6, ifsin6, clnt_sa->sa_len); 279 newsin6->sin6_port = servsin6->sin6_port; 280 tbuf.maxlen = sizeof (struct sockaddr_storage); 281 tbuf.len = clnt_sa->sa_len; 282 tbuf.buf = newsin6; 283 break; 284 #endif 285 default: 286 goto freeit; 287 } 288 if (ifap != NULL) 289 ret = taddr2uaddr(nconf, &tbuf); 290 freeit: 291 freenetconfigent(nconf); 292 free(serv_sa); 293 free(serv_nbp); 294 if (clnt_sa != NULL) 295 free(clnt_sa); 296 if (clnt_nbp != NULL) 297 free(clnt_nbp); 298 freeifaddrs(ifp); 299 300 #ifdef ND_DEBUG 301 if (debugging) 302 fprintf(stderr, "addrmerge: returning %s\n", ret); 303 #endif 304 return ret; 305 } 306 307 void 308 network_init() 309 { 310 #ifdef INET6 311 struct ifaddrs *ifap, *ifp; 312 struct ipv6_mreq mreq6; 313 int ifindex, s; 314 #endif 315 int ecode; 316 struct addrinfo hints, *res; 317 318 memset(&hints, 0, sizeof hints); 319 hints.ai_family = AF_INET; 320 if ((ecode = getaddrinfo(NULL, "sunrpc", &hints, &res))) { 321 if (debugging) 322 fprintf(stderr, "can't get local ip4 address: %s\n", 323 gai_strerror(ecode)); 324 } else { 325 local_in4 = (struct sockaddr_in *)malloc(sizeof *local_in4); 326 if (local_in4 == NULL) { 327 if (debugging) 328 fprintf(stderr, "can't alloc local ip4 addr\n"); 329 } 330 memcpy(local_in4, res->ai_addr, sizeof *local_in4); 331 } 332 333 #ifdef INET6 334 hints.ai_family = AF_INET6; 335 if ((ecode = getaddrinfo(NULL, "sunrpc", &hints, &res))) { 336 if (debugging) 337 fprintf(stderr, "can't get local ip6 address: %s\n", 338 gai_strerror(ecode)); 339 } else { 340 local_in6 = (struct sockaddr_in6 *)malloc(sizeof *local_in6); 341 if (local_in6 == NULL) { 342 if (debugging) 343 fprintf(stderr, "can't alloc local ip6 addr\n"); 344 } 345 memcpy(local_in6, res->ai_addr, sizeof *local_in6); 346 } 347 348 /* 349 * Now join the RPC ipv6 multicast group on all interfaces. 350 */ 351 if (getifaddrs(&ifp) < 0) 352 return; 353 354 mreq6.ipv6mr_interface = 0; 355 inet_pton(AF_INET6, RPCB_MULTICAST_ADDR, &mreq6.ipv6mr_multiaddr); 356 357 s = socket(AF_INET6, SOCK_DGRAM, IPPROTO_UDP); 358 359 /* 360 * Loop through all interfaces. For each interface, see if the 361 * network portion of its address is equal to that of the client. 362 * If so, we have found the interface that we want to use. 363 */ 364 for (ifap = ifp; ifap != NULL; ifap = ifap->ifa_next) { 365 if (ifap->ifa_addr->sa_family != AF_INET6 || 366 !(ifap->ifa_flags & IFF_MULTICAST)) 367 continue; 368 ifindex = if_nametoindex(ifap->ifa_name); 369 if (ifindex == mreq6.ipv6mr_interface) 370 /* 371 * Already did this one. 372 */ 373 continue; 374 mreq6.ipv6mr_interface = ifindex; 375 if (setsockopt(s, IPPROTO_IPV6, IPV6_JOIN_GROUP, &mreq6, 376 sizeof mreq6) < 0) 377 if (debugging) 378 perror("setsockopt v6 multicast"); 379 } 380 #endif 381 382 /* close(s); */ 383 } 384 385 struct sockaddr * 386 local_sa(int af) 387 { 388 switch (af) { 389 case AF_INET: 390 return (struct sockaddr *)local_in4; 391 #ifdef INET6 392 case AF_INET6: 393 return (struct sockaddr *)local_in6; 394 #endif 395 default: 396 return NULL; 397 } 398 } 399