1 /*- 2 * SPDX-License-Identifier: BSD-2-Clause 3 * 4 * Copyright (c) 1994, Garrett Wollman 5 * 6 * Redistribution and use in source and binary forms, with or without 7 * modification, are permitted provided that the following conditions 8 * are met: 9 * 1. Redistributions of source code must retain the above copyright 10 * notice, this list of conditions and the following disclaimer. 11 * 2. Redistributions in binary form must reproduce the above copyright 12 * notice, this list of conditions and the following disclaimer in the 13 * documentation and/or other materials provided with the distribution. 14 * 15 * THIS SOFTWARE IS PROVIDED BY THE CONTRIBUTORS ``AS IS'' AND 16 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 17 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 18 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 19 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 20 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 21 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 22 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 23 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 24 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 25 * SUCH DAMAGE. 26 */ 27 28 #include <sys/cdefs.h> 29 #include "namespace.h" 30 #include "reentrant.h" 31 #include <sys/param.h> 32 #include <sys/socket.h> 33 #include <netinet/in.h> 34 #include <arpa/inet.h> 35 #include <netdb.h> 36 #include <stdio.h> 37 #include <ctype.h> 38 #include <errno.h> 39 #include <stdlib.h> 40 #include <string.h> 41 #include <stdarg.h> 42 #include <nsswitch.h> 43 #include "un-namespace.h" 44 #include "netdb_private.h" 45 #ifdef NS_CACHING 46 #include "nscache.h" 47 #endif 48 49 /* Network lookup order if nsswitch.conf is broken or nonexistent */ 50 static const ns_src default_src[] = { 51 { NSSRC_FILES, NS_SUCCESS }, 52 { NSSRC_DNS, NS_SUCCESS }, 53 { 0 } 54 }; 55 56 NETDB_THREAD_ALLOC(netent_data) 57 NETDB_THREAD_ALLOC(netdata) 58 59 #ifdef NS_CACHING 60 static int 61 net_id_func(char *buffer, size_t *buffer_size, va_list ap, void *cache_mdata) 62 { 63 char *name; 64 uint32_t net; 65 int type; 66 67 size_t desired_size, size; 68 enum nss_lookup_type lookup_type; 69 int res = NS_UNAVAIL; 70 71 lookup_type = (enum nss_lookup_type)(uintptr_t)cache_mdata; 72 switch (lookup_type) { 73 case nss_lt_name: 74 name = va_arg(ap, char *); 75 76 size = strlen(name); 77 desired_size = sizeof(enum nss_lookup_type) + size + 1; 78 if (desired_size > *buffer_size) { 79 res = NS_RETURN; 80 goto fin; 81 } 82 83 memcpy(buffer, &lookup_type, sizeof(enum nss_lookup_type)); 84 memcpy(buffer + sizeof(enum nss_lookup_type), name, size + 1); 85 86 res = NS_SUCCESS; 87 break; 88 case nss_lt_id: 89 net = va_arg(ap, uint32_t); 90 type = va_arg(ap, int); 91 92 desired_size = sizeof(enum nss_lookup_type) + 93 sizeof(uint32_t) + sizeof(int); 94 if (desired_size > *buffer_size) { 95 res = NS_RETURN; 96 goto fin; 97 } 98 99 memcpy(buffer, &lookup_type, sizeof(enum nss_lookup_type)); 100 memcpy(buffer + sizeof(enum nss_lookup_type), &net, 101 sizeof(uint32_t)); 102 memcpy(buffer + sizeof(enum nss_lookup_type) + sizeof(uint32_t), 103 &type, sizeof(int)); 104 105 res = NS_SUCCESS; 106 break; 107 default: 108 /* should be unreachable */ 109 return (NS_UNAVAIL); 110 } 111 112 fin: 113 *buffer_size = desired_size; 114 return (res); 115 } 116 117 118 static int 119 net_marshal_func(char *buffer, size_t *buffer_size, void *retval, va_list ap, 120 void *cache_mdata) 121 { 122 char *name __unused; 123 uint32_t net __unused; 124 int type __unused; 125 struct netent *ne; 126 char *orig_buf __unused; 127 size_t orig_buf_size __unused; 128 129 struct netent new_ne; 130 size_t desired_size, size, aliases_size; 131 char *p; 132 char **alias; 133 134 switch ((enum nss_lookup_type)(uintptr_t)cache_mdata) { 135 case nss_lt_name: 136 name = va_arg(ap, char *); 137 break; 138 case nss_lt_id: 139 net = va_arg(ap, uint32_t); 140 type = va_arg(ap, int); 141 break; 142 case nss_lt_all: 143 break; 144 default: 145 /* should be unreachable */ 146 return (NS_UNAVAIL); 147 } 148 149 ne = va_arg(ap, struct netent *); 150 orig_buf = va_arg(ap, char *); 151 orig_buf_size = va_arg(ap, size_t); 152 153 desired_size = _ALIGNBYTES + sizeof(struct netent) + sizeof(char *); 154 if (ne->n_name != NULL) 155 desired_size += strlen(ne->n_name) + 1; 156 157 if (ne->n_aliases != NULL) { 158 aliases_size = 0; 159 for (alias = ne->n_aliases; *alias; ++alias) { 160 desired_size += strlen(*alias) + 1; 161 ++aliases_size; 162 } 163 164 desired_size += _ALIGNBYTES + 165 (aliases_size + 1) * sizeof(char *); 166 } 167 168 if (*buffer_size < desired_size) { 169 /* this assignment is here for future use */ 170 *buffer_size = desired_size; 171 return (NS_RETURN); 172 } 173 174 memcpy(&new_ne, ne, sizeof(struct netent)); 175 176 *buffer_size = desired_size; 177 memset(buffer, 0, desired_size); 178 p = buffer + sizeof(struct netent) + sizeof(char *); 179 memcpy(buffer + sizeof(struct netent), &p, sizeof(char *)); 180 p = (char *)_ALIGN(p); 181 182 if (new_ne.n_name != NULL) { 183 size = strlen(new_ne.n_name); 184 memcpy(p, new_ne.n_name, size); 185 new_ne.n_name = p; 186 p += size + 1; 187 } 188 189 if (new_ne.n_aliases != NULL) { 190 p = (char *)_ALIGN(p); 191 memcpy(p, new_ne.n_aliases, sizeof(char *) * aliases_size); 192 new_ne.n_aliases = (char **)p; 193 p += sizeof(char *) * (aliases_size + 1); 194 195 for (alias = new_ne.n_aliases; *alias; ++alias) { 196 size = strlen(*alias); 197 memcpy(p, *alias, size); 198 *alias = p; 199 p += size + 1; 200 } 201 } 202 203 memcpy(buffer, &new_ne, sizeof(struct netent)); 204 return (NS_SUCCESS); 205 } 206 207 static int 208 net_unmarshal_func(char *buffer, size_t buffer_size, void *retval, va_list ap, 209 void *cache_mdata) 210 { 211 char *name __unused; 212 uint32_t net __unused; 213 int type __unused; 214 struct netent *ne; 215 char *orig_buf; 216 size_t orig_buf_size; 217 int *ret_errno; 218 219 char *p; 220 char **alias; 221 222 switch ((enum nss_lookup_type)(uintptr_t)cache_mdata) { 223 case nss_lt_name: 224 name = va_arg(ap, char *); 225 break; 226 case nss_lt_id: 227 net = va_arg(ap, uint32_t); 228 type = va_arg(ap, int); 229 break; 230 case nss_lt_all: 231 break; 232 default: 233 /* should be unreachable */ 234 return (NS_UNAVAIL); 235 } 236 237 ne = va_arg(ap, struct netent *); 238 orig_buf = va_arg(ap, char *); 239 orig_buf_size = va_arg(ap, size_t); 240 ret_errno = va_arg(ap, int *); 241 242 if (orig_buf_size < 243 buffer_size - sizeof(struct netent) - sizeof(char *)) { 244 *ret_errno = ERANGE; 245 return (NS_RETURN); 246 } 247 248 memcpy(ne, buffer, sizeof(struct netent)); 249 memcpy(&p, buffer + sizeof(struct netent), sizeof(char *)); 250 251 orig_buf = (char *)_ALIGN(orig_buf); 252 memcpy(orig_buf, buffer + sizeof(struct netent) + sizeof(char *) + 253 _ALIGN(p) - (size_t)p, 254 buffer_size - sizeof(struct netent) - sizeof(char *) - 255 _ALIGN(p) + (size_t)p); 256 p = (char *)_ALIGN(p); 257 258 NS_APPLY_OFFSET(ne->n_name, orig_buf, p, char *); 259 if (ne->n_aliases != NULL) { 260 NS_APPLY_OFFSET(ne->n_aliases, orig_buf, p, char **); 261 262 for (alias = ne->n_aliases; *alias; ++alias) 263 NS_APPLY_OFFSET(*alias, orig_buf, p, char *); 264 } 265 266 if (retval != NULL) 267 *((struct netent **)retval) = ne; 268 269 return (NS_SUCCESS); 270 } 271 #endif /* NS_CACHING */ 272 273 static void 274 netent_data_free(void *ptr) 275 { 276 struct netent_data *ned = ptr; 277 278 if (ned == NULL) 279 return; 280 ned->stayopen = 0; 281 _endnethtent(ned); 282 free(ned); 283 } 284 285 static void 286 netdata_free(void *ptr) 287 { 288 free(ptr); 289 } 290 291 int 292 __copy_netent(struct netent *ne, struct netent *nptr, char *buf, size_t buflen) 293 { 294 char *cp; 295 int i, n; 296 int numptr, len; 297 298 /* Find out the amount of space required to store the answer. */ 299 numptr = 1; /* NULL ptr */ 300 len = (char *)ALIGN(buf) - buf; 301 for (i = 0; ne->n_aliases[i]; i++, numptr++) { 302 len += strlen(ne->n_aliases[i]) + 1; 303 } 304 len += strlen(ne->n_name) + 1; 305 len += numptr * sizeof(char*); 306 307 if (len > (int)buflen) { 308 errno = ERANGE; 309 return (-1); 310 } 311 312 /* copy net value and type */ 313 nptr->n_addrtype = ne->n_addrtype; 314 nptr->n_net = ne->n_net; 315 316 cp = (char *)ALIGN(buf) + numptr * sizeof(char *); 317 318 /* copy official name */ 319 n = strlen(ne->n_name) + 1; 320 strcpy(cp, ne->n_name); 321 nptr->n_name = cp; 322 cp += n; 323 324 /* copy aliases */ 325 nptr->n_aliases = (char **)ALIGN(buf); 326 for (i = 0 ; ne->n_aliases[i]; i++) { 327 n = strlen(ne->n_aliases[i]) + 1; 328 strcpy(cp, ne->n_aliases[i]); 329 nptr->n_aliases[i] = cp; 330 cp += n; 331 } 332 nptr->n_aliases[i] = NULL; 333 334 return (0); 335 } 336 337 int 338 getnetbyname_r(const char *name, struct netent *ne, char *buffer, 339 size_t buflen, struct netent **result, int *h_errorp) 340 { 341 #ifdef NS_CACHING 342 static const nss_cache_info cache_info = 343 NS_COMMON_CACHE_INFO_INITIALIZER( 344 networks, (void *)nss_lt_name, 345 net_id_func, net_marshal_func, net_unmarshal_func); 346 #endif 347 static const ns_dtab dtab[] = { 348 NS_FILES_CB(_ht_getnetbyname, NULL) 349 { NSSRC_DNS, _dns_getnetbyname, NULL }, 350 NS_NIS_CB(_nis_getnetbyname, NULL) /* force -DHESIOD */ 351 #ifdef NS_CACHING 352 NS_CACHE_CB(&cache_info) 353 #endif 354 { 0 } 355 }; 356 int rval, ret_errno = 0; 357 358 rval = _nsdispatch((void *)result, dtab, NSDB_NETWORKS, 359 "getnetbyname_r", default_src, name, ne, buffer, buflen, 360 &ret_errno, h_errorp); 361 362 if (rval != NS_SUCCESS) { 363 errno = ret_errno; 364 return ((ret_errno != 0) ? ret_errno : -1); 365 } 366 return (0); 367 } 368 369 int 370 getnetbyaddr_r(uint32_t addr, int af, struct netent *ne, char *buffer, 371 size_t buflen, struct netent **result, int *h_errorp) 372 { 373 #ifdef NS_CACHING 374 static const nss_cache_info cache_info = 375 NS_COMMON_CACHE_INFO_INITIALIZER( 376 networks, (void *)nss_lt_id, 377 net_id_func, net_marshal_func, net_unmarshal_func); 378 #endif 379 static const ns_dtab dtab[] = { 380 NS_FILES_CB(_ht_getnetbyaddr, NULL) 381 { NSSRC_DNS, _dns_getnetbyaddr, NULL }, 382 NS_NIS_CB(_nis_getnetbyaddr, NULL) /* force -DHESIOD */ 383 #ifdef NS_CACHING 384 NS_CACHE_CB(&cache_info) 385 #endif 386 { 0 } 387 }; 388 int rval, ret_errno = 0; 389 390 rval = _nsdispatch((void *)result, dtab, NSDB_NETWORKS, 391 "getnetbyaddr_r", default_src, addr, af, ne, buffer, buflen, 392 &ret_errno, h_errorp); 393 394 if (rval != NS_SUCCESS) { 395 errno = ret_errno; 396 return ((ret_errno != 0) ? ret_errno : -1); 397 } 398 return (0); 399 } 400 401 struct netent * 402 getnetbyname(const char *name) 403 { 404 struct netdata *nd; 405 struct netent *rval; 406 int ret_h_errno; 407 408 if ((nd = __netdata_init()) == NULL) 409 return (NULL); 410 if (getnetbyname_r(name, &nd->net, nd->data, sizeof(nd->data), &rval, 411 &ret_h_errno) != 0) 412 return (NULL); 413 return (rval); 414 } 415 416 struct netent * 417 getnetbyaddr(uint32_t addr, int af) 418 { 419 struct netdata *nd; 420 struct netent *rval; 421 int ret_h_errno; 422 423 if ((nd = __netdata_init()) == NULL) 424 return (NULL); 425 if (getnetbyaddr_r(addr, af, &nd->net, nd->data, sizeof(nd->data), 426 &rval, &ret_h_errno) != 0) 427 return (NULL); 428 return (rval); 429 } 430 431 void 432 setnetent(int stayopen) 433 { 434 struct netent_data *ned; 435 436 if ((ned = __netent_data_init()) == NULL) 437 return; 438 _setnethtent(stayopen, ned); 439 _setnetdnsent(stayopen); 440 } 441 442 void 443 endnetent(void) 444 { 445 struct netent_data *ned; 446 447 if ((ned = __netent_data_init()) == NULL) 448 return; 449 _endnethtent(ned); 450 _endnetdnsent(); 451 } 452