1 /* $NetBSD: util.c,v 1.5 2001/01/10 05:23:43 jmc 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 clnt_sa = (struct sockaddr *)clnt_nbp->buf; 148 } else { 149 clnt_sa = (struct sockaddr *) 150 malloc(sizeof (struct sockaddr_storage)); 151 memcpy(clnt_sa, clnt, clnt->sa_len); 152 } 153 154 if (getifaddrs(&ifp) < 0) 155 return 0; 156 157 /* 158 * Loop through all interfaces. For each interface, see if the 159 * network portion of its address is equal to that of the client. 160 * If so, we have found the interface that we want to use. 161 */ 162 for (ifap = ifp; ifap != NULL; ifap = ifap->ifa_next) { 163 if (ifap->ifa_addr->sa_family != clnt->sa_family || 164 !(ifap->ifa_flags & IFF_UP)) 165 continue; 166 167 switch (clnt->sa_family) { 168 case AF_INET: 169 /* 170 * realsin: address that recvfrom gave us. 171 * ifsin: address of interface being examined. 172 * clntsin: address that client want us to contact 173 * it on 174 * servsin: local address of RPC service. 175 * sinmask: netmask of this interface 176 * newsin: initially a copy of clntsin, eventually 177 * the merged address 178 */ 179 servsin = (struct sockaddr_in *)serv_sa; 180 clntsin = (struct sockaddr_in *)clnt_sa; 181 sinmask = (struct sockaddr_in *)ifap->ifa_netmask; 182 newsin = (struct sockaddr_in *)&ss; 183 ifsin = (struct sockaddr_in *)ifap->ifa_addr; 184 if (!bitmaskcmp(&ifsin->sin_addr, &clntsin->sin_addr, 185 &sinmask->sin_addr, sizeof (struct in_addr))) { 186 goto found; 187 } 188 break; 189 #ifdef INET6 190 case AF_INET6: 191 /* 192 * realsin6: address that recvfrom gave us. 193 * ifsin6: address of interface being examined. 194 * clntsin6: address that client want us to contact 195 * it on 196 * servsin6: local address of RPC service. 197 * sin6mask: netmask of this interface 198 * newsin6: initially a copy of clntsin, eventually 199 * the merged address 200 * 201 * For v6 link local addresses, if the client contacted 202 * us via a link-local address, and wants us to reply 203 * to one, use the scope id to see which one. 204 */ 205 realsin6 = (struct sockaddr_in6 *)clnt; 206 ifsin6 = (struct sockaddr_in6 *)ifap->ifa_addr; 207 in6_fillscopeid(ifsin6); 208 clntsin6 = (struct sockaddr_in6 *)clnt_sa; 209 servsin6 = (struct sockaddr_in6 *)serv_sa; 210 sin6mask = (struct sockaddr_in6 *)ifap->ifa_netmask; 211 newsin6 = (struct sockaddr_in6 *)&ss; 212 if (IN6_IS_ADDR_LINKLOCAL(&ifsin6->sin6_addr) && 213 IN6_IS_ADDR_LINKLOCAL(&realsin6->sin6_addr) && 214 IN6_IS_ADDR_LINKLOCAL(&clntsin6->sin6_addr)) { 215 if (ifsin6->sin6_scope_id != 216 realsin6->sin6_scope_id) 217 continue; 218 goto found; 219 } 220 if (!bitmaskcmp(&ifsin6->sin6_addr, 221 &clntsin6->sin6_addr, &sin6mask->sin6_addr, 222 sizeof (struct in6_addr))) 223 goto found; 224 break; 225 #endif 226 default: 227 goto freeit; 228 } 229 } 230 /* 231 * Didn't find anything. Get the first possibly useful interface, 232 * preferring "normal" interfaces to point-to-point and loopback 233 * ones. 234 */ 235 bestif = NULL; 236 for (ifap = ifp; ifap != NULL; ifap = ifap->ifa_next) { 237 if (ifap->ifa_addr->sa_family != clnt->sa_family || 238 !(ifap->ifa_flags & IFF_UP)) 239 continue; 240 if (!(ifap->ifa_flags & IFF_LOOPBACK) && 241 !(ifap->ifa_flags & IFF_POINTOPOINT)) { 242 bestif = ifap; 243 break; 244 } 245 if (bestif == NULL) 246 bestif = ifap; 247 else if ((bestif->ifa_flags & IFF_LOOPBACK) && 248 !(ifap->ifa_flags & IFF_LOOPBACK)) 249 bestif = ifap; 250 } 251 ifap = bestif; 252 found: 253 switch (clnt->sa_family) { 254 case AF_INET: 255 memcpy(newsin, ifap->ifa_addr, clnt_sa->sa_len); 256 newsin->sin_port = servsin->sin_port; 257 tbuf.len = clnt_sa->sa_len; 258 tbuf.maxlen = sizeof (struct sockaddr_storage); 259 tbuf.buf = newsin; 260 break; 261 #ifdef INET6 262 case AF_INET6: 263 memcpy(newsin6, ifsin6, clnt_sa->sa_len); 264 newsin6->sin6_port = servsin6->sin6_port; 265 tbuf.maxlen = sizeof (struct sockaddr_storage); 266 tbuf.len = clnt_sa->sa_len; 267 tbuf.buf = newsin6; 268 break; 269 #endif 270 default: 271 goto freeit; 272 } 273 if (ifap != NULL) 274 ret = taddr2uaddr(nconf, &tbuf); 275 freeit: 276 freenetconfigent(nconf); 277 free(serv_sa); 278 free(serv_nbp); 279 if (clnt_sa != NULL) 280 free(clnt_sa); 281 if (clnt_nbp != NULL) 282 free(clnt_nbp); 283 freeifaddrs(ifp); 284 285 #ifdef ND_DEBUG 286 if (debugging) 287 fprintf(stderr, "addrmerge: returning %s\n", ret); 288 #endif 289 return ret; 290 } 291 292 void 293 network_init() 294 { 295 #ifdef INET6 296 struct ifaddrs *ifap, *ifp; 297 struct ipv6_mreq mreq6; 298 int ifindex, s; 299 #endif 300 int ecode; 301 struct addrinfo hints, *res; 302 303 memset(&hints, 0, sizeof hints); 304 hints.ai_family = AF_INET; 305 if ((ecode = getaddrinfo(NULL, "sunrpc", &hints, &res))) { 306 if (debugging) 307 fprintf(stderr, "can't get local ip4 address: %s\n", 308 gai_strerror(ecode)); 309 } else { 310 local_in4 = (struct sockaddr_in *)malloc(sizeof *local_in4); 311 if (local_in4 == NULL) { 312 if (debugging) 313 fprintf(stderr, "can't alloc local ip4 addr\n"); 314 } 315 memcpy(local_in4, res->ai_addr, sizeof *local_in4); 316 } 317 318 #ifdef INET6 319 hints.ai_family = AF_INET6; 320 if ((ecode = getaddrinfo(NULL, "sunrpc", &hints, &res))) { 321 if (debugging) 322 fprintf(stderr, "can't get local ip6 address: %s\n", 323 gai_strerror(ecode)); 324 } else { 325 local_in6 = (struct sockaddr_in6 *)malloc(sizeof *local_in6); 326 if (local_in6 == NULL) { 327 if (debugging) 328 fprintf(stderr, "can't alloc local ip6 addr\n"); 329 } 330 memcpy(local_in6, res->ai_addr, sizeof *local_in6); 331 } 332 333 /* 334 * Now join the RPC ipv6 multicast group on all interfaces. 335 */ 336 if (getifaddrs(&ifp) < 0) 337 return; 338 339 mreq6.ipv6mr_interface = 0; 340 inet_pton(AF_INET6, RPCB_MULTICAST_ADDR, &mreq6.ipv6mr_multiaddr); 341 342 s = socket(AF_INET6, SOCK_DGRAM, IPPROTO_UDP); 343 344 /* 345 * Loop through all interfaces. For each interface, see if the 346 * network portion of its address is equal to that of the client. 347 * If so, we have found the interface that we want to use. 348 */ 349 for (ifap = ifp; ifap != NULL; ifap = ifap->ifa_next) { 350 if (ifap->ifa_addr->sa_family != AF_INET6 || 351 !(ifap->ifa_flags & IFF_MULTICAST)) 352 continue; 353 ifindex = if_nametoindex(ifap->ifa_name); 354 if (ifindex == mreq6.ipv6mr_interface) 355 /* 356 * Already did this one. 357 */ 358 continue; 359 mreq6.ipv6mr_interface = ifindex; 360 if (setsockopt(s, IPPROTO_IPV6, IPV6_JOIN_GROUP, &mreq6, 361 sizeof mreq6) < 0) 362 if (debugging) 363 perror("setsockopt v6 multicast"); 364 } 365 #endif 366 367 /* close(s); */ 368 } 369 370 struct sockaddr * 371 local_sa(int af) 372 { 373 switch (af) { 374 case AF_INET: 375 return (struct sockaddr *)local_in4; 376 #ifdef INET6 377 case AF_INET6: 378 return (struct sockaddr *)local_in6; 379 #endif 380 default: 381 return NULL; 382 } 383 } 384