1 /* $NetBSD: getaddrinfo.c,v 1.3 2023/06/19 21:41:45 christos Exp $ */ 2 3 /* 4 * Copyright (c) 1999 - 2001 Kungliga Tekniska Högskolan 5 * (Royal Institute of Technology, Stockholm, Sweden). 6 * All rights reserved. 7 * 8 * Redistribution and use in source and binary forms, with or without 9 * modification, are permitted provided that the following conditions 10 * are met: 11 * 12 * 1. Redistributions of source code must retain the above copyright 13 * notice, this list of conditions and the following disclaimer. 14 * 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 * 19 * 3. Neither the name of the Institute nor the names of its contributors 20 * may be used to endorse or promote products derived from this software 21 * without specific prior written permission. 22 * 23 * THIS SOFTWARE IS PROVIDED BY THE INSTITUTE AND CONTRIBUTORS ``AS IS'' AND 24 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 25 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 26 * ARE DISCLAIMED. IN NO EVENT SHALL THE INSTITUTE OR CONTRIBUTORS BE LIABLE 27 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 28 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 29 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 30 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 31 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 32 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 33 * SUCH DAMAGE. 34 */ 35 36 #include <config.h> 37 38 #include <krb5/roken.h> 39 40 /* 41 * uses hints->ai_socktype and hints->ai_protocol 42 */ 43 44 static int 45 get_port_protocol_socktype (const char *servname, 46 const struct addrinfo *hints, 47 int *port, 48 int *protocol, 49 int *socktype) 50 { 51 struct servent *se; 52 const char *proto_str = NULL; 53 54 *socktype = 0; 55 56 if (hints != NULL && hints->ai_protocol != 0) { 57 struct protoent *protoent = getprotobynumber (hints->ai_protocol); 58 59 if (protoent == NULL) 60 return EAI_SOCKTYPE; /* XXX */ 61 62 proto_str = protoent->p_name; 63 *protocol = protoent->p_proto; 64 } 65 66 if (hints != NULL) 67 *socktype = hints->ai_socktype; 68 69 if (*socktype == SOCK_STREAM) { 70 se = getservbyname (servname, proto_str ? proto_str : "tcp"); 71 if (proto_str == NULL) 72 *protocol = IPPROTO_TCP; 73 } else if (*socktype == SOCK_DGRAM) { 74 se = getservbyname (servname, proto_str ? proto_str : "udp"); 75 if (proto_str == NULL) 76 *protocol = IPPROTO_UDP; 77 } else if (*socktype == 0) { 78 if (proto_str != NULL) { 79 se = getservbyname (servname, proto_str); 80 } else { 81 se = getservbyname (servname, "tcp"); 82 *protocol = IPPROTO_TCP; 83 *socktype = SOCK_STREAM; 84 if (se == NULL) { 85 se = getservbyname (servname, "udp"); 86 *protocol = IPPROTO_UDP; 87 *socktype = SOCK_DGRAM; 88 } 89 } 90 } else 91 return EAI_SOCKTYPE; 92 93 if (se == NULL) { 94 char *endstr; 95 96 *port = htons(strtol (servname, &endstr, 10)); 97 if (servname == endstr) 98 return EAI_NONAME; 99 } else { 100 *port = se->s_port; 101 } 102 return 0; 103 } 104 105 static int 106 add_one (int port, int protocol, int socktype, 107 struct addrinfo ***ptr, 108 int (*func)(struct addrinfo *, void *data, int port), 109 void *data, 110 char *canonname) 111 { 112 struct addrinfo *a; 113 int ret; 114 115 a = malloc (sizeof (*a)); 116 if (a == NULL) 117 return EAI_MEMORY; 118 memset (a, 0, sizeof(*a)); 119 a->ai_flags = 0; 120 a->ai_next = NULL; 121 a->ai_protocol = protocol; 122 a->ai_socktype = socktype; 123 a->ai_canonname = canonname; 124 ret = (*func)(a, data, port); 125 if (ret) { 126 free (a); 127 return ret; 128 } 129 **ptr = a; 130 *ptr = &a->ai_next; 131 return 0; 132 } 133 134 static int 135 const_v4 (struct addrinfo *a, void *data, int port) 136 { 137 struct sockaddr_in *sin4; 138 struct in_addr *addr = (struct in_addr *)data; 139 140 a->ai_family = PF_INET; 141 a->ai_addrlen = sizeof(*sin4); 142 a->ai_addr = malloc (sizeof(*sin4)); 143 if (a->ai_addr == NULL) 144 return EAI_MEMORY; 145 sin4 = (struct sockaddr_in *)a->ai_addr; 146 memset (sin4, 0, sizeof(*sin4)); 147 sin4->sin_family = AF_INET; 148 sin4->sin_port = port; 149 sin4->sin_addr = *addr; 150 return 0; 151 } 152 153 #ifdef HAVE_IPV6 154 static int 155 const_v6 (struct addrinfo *a, void *data, int port) 156 { 157 struct sockaddr_in6 *sin6; 158 struct in6_addr *addr = (struct in6_addr *)data; 159 160 a->ai_family = PF_INET6; 161 a->ai_addrlen = sizeof(*sin6); 162 a->ai_addr = malloc (sizeof(*sin6)); 163 if (a->ai_addr == NULL) 164 return EAI_MEMORY; 165 sin6 = (struct sockaddr_in6 *)a->ai_addr; 166 memset (sin6, 0, sizeof(*sin6)); 167 sin6->sin6_family = AF_INET6; 168 sin6->sin6_port = port; 169 sin6->sin6_addr = *addr; 170 return 0; 171 } 172 #endif 173 174 /* this is mostly a hack for some versions of AIX that has a prototype 175 for in6addr_loopback but no actual symbol in libc */ 176 #if defined(HAVE_IPV6) && !defined(HAVE_IN6ADDR_LOOPBACK) && defined(IN6ADDR_LOOPBACK_INIT) 177 #define in6addr_loopback _roken_in6addr_loopback 178 struct in6_addr in6addr_loopback = IN6ADDR_LOOPBACK_INIT; 179 #endif 180 181 static int 182 get_null (const struct addrinfo *hints, 183 int port, int protocol, int socktype, 184 struct addrinfo **res) 185 { 186 struct in_addr v4_addr; 187 #ifdef HAVE_IPV6 188 struct in6_addr v6_addr; 189 #endif 190 struct addrinfo *first = NULL; 191 struct addrinfo **current = &first; 192 int family = PF_UNSPEC; 193 int ret = 0; 194 195 if (hints != NULL) 196 family = hints->ai_family; 197 198 if (hints && hints->ai_flags & AI_PASSIVE) { 199 v4_addr.s_addr = INADDR_ANY; 200 #ifdef HAVE_IPV6 201 v6_addr = in6addr_any; 202 #endif 203 } else { 204 v4_addr.s_addr = htonl(INADDR_LOOPBACK); 205 #ifdef HAVE_IPV6 206 v6_addr = in6addr_loopback; 207 #endif 208 } 209 210 #ifdef HAVE_IPV6 211 if (family == PF_INET6 || family == PF_UNSPEC) { 212 ret = add_one (port, protocol, socktype, 213 ¤t, const_v6, &v6_addr, NULL); 214 if (ret) 215 return ret; 216 } 217 #endif 218 if (family == PF_INET || family == PF_UNSPEC) { 219 ret = add_one (port, protocol, socktype, 220 ¤t, const_v4, &v4_addr, NULL); 221 } 222 *res = first; 223 return ret; 224 } 225 226 static int 227 add_hostent (int port, int protocol, int socktype, 228 struct addrinfo ***current, 229 int (*func)(struct addrinfo *, void *data, int port), 230 struct hostent *he, int *flags) 231 { 232 int ret; 233 char *canonname = NULL; 234 char **h; 235 236 if (*flags & AI_CANONNAME) { 237 struct hostent *he2 = NULL; 238 const char *tmp_canon; 239 240 tmp_canon = hostent_find_fqdn (he); 241 if (strchr (tmp_canon, '.') == NULL) { 242 int error; 243 244 he2 = getipnodebyaddr (he->h_addr_list[0], he->h_length, 245 he->h_addrtype, &error); 246 if (he2 != NULL) { 247 const char *tmp = hostent_find_fqdn (he2); 248 249 if (strchr (tmp, '.') != NULL) 250 tmp_canon = tmp; 251 } 252 } 253 254 canonname = strdup (tmp_canon); 255 if (he2 != NULL) 256 freehostent (he2); 257 if (canonname == NULL) 258 return EAI_MEMORY; 259 } 260 261 for (h = he->h_addr_list; *h != NULL; ++h) { 262 ret = add_one (port, protocol, socktype, 263 current, func, *h, canonname); 264 if (ret) 265 return ret; 266 if (*flags & AI_CANONNAME) { 267 *flags &= ~AI_CANONNAME; 268 canonname = NULL; 269 } 270 } 271 return 0; 272 } 273 274 static int 275 get_number (const char *nodename, 276 const struct addrinfo *hints, 277 int port, int protocol, int socktype, 278 struct addrinfo **res) 279 { 280 struct addrinfo *first = NULL; 281 struct addrinfo **current = &first; 282 int family = PF_UNSPEC; 283 int ret; 284 285 if (hints != NULL) { 286 family = hints->ai_family; 287 } 288 289 #ifdef HAVE_IPV6 290 if (family == PF_INET6 || family == PF_UNSPEC) { 291 struct in6_addr v6_addr; 292 293 if (inet_pton (PF_INET6, nodename, &v6_addr) == 1) { 294 ret = add_one (port, protocol, socktype, 295 ¤t, const_v6, &v6_addr, NULL); 296 *res = first; 297 return ret; 298 } 299 } 300 #endif 301 if (family == PF_INET || family == PF_UNSPEC) { 302 struct in_addr v4_addr; 303 304 if (inet_pton (PF_INET, nodename, &v4_addr) == 1) { 305 ret = add_one (port, protocol, socktype, 306 ¤t, const_v4, &v4_addr, NULL); 307 *res = first; 308 return ret; 309 } 310 } 311 return EAI_NONAME; 312 } 313 314 static int 315 get_nodes (const char *nodename, 316 const struct addrinfo *hints, 317 int port, int protocol, int socktype, 318 struct addrinfo **res) 319 { 320 struct addrinfo *first = NULL; 321 struct addrinfo **current = &first; 322 int family = PF_UNSPEC; 323 int flags = 0; 324 int ret = EAI_NONAME; 325 int error; 326 327 if (hints != NULL) { 328 family = hints->ai_family; 329 flags = hints->ai_flags; 330 } 331 332 #ifdef HAVE_IPV6 333 if (family == PF_INET6 || family == PF_UNSPEC) { 334 struct hostent *he; 335 336 he = getipnodebyname (nodename, PF_INET6, 0, &error); 337 338 if (he != NULL) { 339 ret = add_hostent (port, protocol, socktype, 340 ¤t, const_v6, he, &flags); 341 freehostent (he); 342 } 343 } 344 #endif 345 if (family == PF_INET || family == PF_UNSPEC) { 346 struct hostent *he; 347 348 he = getipnodebyname (nodename, PF_INET, 0, &error); 349 350 if (he != NULL) { 351 ret = add_hostent (port, protocol, socktype, 352 ¤t, const_v4, he, &flags); 353 freehostent (he); 354 } 355 } 356 *res = first; 357 return ret; 358 } 359 360 /* 361 * hints: 362 * 363 * struct addrinfo { 364 * int ai_flags; 365 * int ai_family; 366 * int ai_socktype; 367 * int ai_protocol; 368 * ... 369 * }; 370 */ 371 372 ROKEN_LIB_FUNCTION int ROKEN_LIB_CALL 373 getaddrinfo(const char *nodename, 374 const char *servname, 375 const struct addrinfo *hints, 376 struct addrinfo **res) 377 { 378 int ret; 379 int port = 0; 380 int protocol = 0; 381 int socktype = 0; 382 383 *res = NULL; 384 385 if (servname == NULL && nodename == NULL) 386 return EAI_NONAME; 387 388 if (hints != NULL 389 && hints->ai_family != PF_UNSPEC 390 && hints->ai_family != PF_INET 391 #ifdef HAVE_IPV6 392 && hints->ai_family != PF_INET6 393 #endif 394 ) 395 return EAI_FAMILY; 396 397 if (servname != NULL) { 398 ret = get_port_protocol_socktype (servname, hints, 399 &port, &protocol, &socktype); 400 if (ret) 401 return ret; 402 } 403 if (nodename != NULL) { 404 ret = get_number (nodename, hints, port, protocol, socktype, res); 405 if (ret) { 406 if(hints && hints->ai_flags & AI_NUMERICHOST) 407 ret = EAI_NONAME; 408 else 409 ret = get_nodes (nodename, hints, port, protocol, socktype, 410 res); 411 } 412 } else { 413 ret = get_null (hints, port, protocol, socktype, res); 414 } 415 if (ret) 416 freeaddrinfo (*res); 417 return ret; 418 } 419