lh | 9ed821d | 2023-04-07 01:36:19 -0700 | [diff] [blame] | 1 | /* |
| 2 | * Copyright (c) 1995-1999 by Internet Software Consortium. |
| 3 | * |
| 4 | * Permission to use, copy, modify, and distribute this software for any |
| 5 | * purpose with or without fee is hereby granted, provided that the above |
| 6 | * copyright notice and this permission notice appear in all copies. |
| 7 | * |
| 8 | * THE SOFTWARE IS PROVIDED "AS IS" AND INTERNET SOFTWARE CONSORTIUM DISCLAIMS |
| 9 | * ALL WARRANTIES WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES |
| 10 | * OF MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL INTERNET SOFTWARE |
| 11 | * CONSORTIUM BE LIABLE FOR ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL |
| 12 | * DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR |
| 13 | * PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS |
| 14 | * ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS |
| 15 | * SOFTWARE. |
| 16 | */ |
| 17 | |
| 18 | #if defined(LIBC_SCCS) && !defined(lint) |
| 19 | static const char rcsid[] = "$BINDId: res_data.c,v 8.17 1999/10/13 17:11:31 vixie Exp $"; |
| 20 | #endif /* LIBC_SCCS and not lint */ |
| 21 | |
| 22 | #include <sys/types.h> |
| 23 | #include <sys/param.h> |
| 24 | #include <sys/socket.h> |
| 25 | #include <sys/time.h> |
| 26 | |
| 27 | #include <netinet/in.h> |
| 28 | #include <arpa/inet.h> |
| 29 | #include <arpa/nameser.h> |
| 30 | |
| 31 | #include <ctype.h> |
| 32 | #include <netdb.h> |
| 33 | #include <resolv.h> |
| 34 | #ifdef BIND_UPDATE |
| 35 | #include <res_update.h> |
| 36 | #endif |
| 37 | #include <stdio.h> |
| 38 | #include <stdlib.h> |
| 39 | #include <string.h> |
| 40 | #include <unistd.h> |
| 41 | |
| 42 | const char *_res_opcodes[] = { |
| 43 | "QUERY", |
| 44 | "IQUERY", |
| 45 | "CQUERYM", |
| 46 | "CQUERYU", /* experimental */ |
| 47 | "NOTIFY", /* experimental */ |
| 48 | "UPDATE", |
| 49 | "6", |
| 50 | "7", |
| 51 | "8", |
| 52 | "9", |
| 53 | "10", |
| 54 | "11", |
| 55 | "12", |
| 56 | "13", |
| 57 | "ZONEINIT", |
| 58 | "ZONEREF", |
| 59 | }; |
| 60 | libresolv_hidden_data_def (_res_opcodes) |
| 61 | |
| 62 | #ifdef BIND_UPDATE |
| 63 | const char *_res_sectioncodes[] attribute_hidden = { |
| 64 | "ZONE", |
| 65 | "PREREQUISITES", |
| 66 | "UPDATE", |
| 67 | "ADDITIONAL", |
| 68 | }; |
| 69 | #endif |
| 70 | |
| 71 | #ifndef __BIND_NOSTATIC |
| 72 | #ifdef _LIBC |
| 73 | /* The definition has been moved to res_libc.c. */ |
| 74 | #else |
| 75 | #undef _res |
| 76 | struct __res_state _res |
| 77 | # if defined(__BIND_RES_TEXT) |
| 78 | = { RES_TIMEOUT, } /* Motorola, et al. */ |
| 79 | # endif |
| 80 | ; |
| 81 | #endif |
| 82 | |
| 83 | /* Proto. */ |
| 84 | #ifndef _LIBC |
| 85 | int res_ourserver_p(const res_state, const struct sockaddr_in *); |
| 86 | void res_pquery(const res_state, const u_char *, int, FILE *); |
| 87 | #endif |
| 88 | |
| 89 | #ifndef _LIBC |
| 90 | /* Moved to res_libc.c since res_init() should go into libc.so but the |
| 91 | rest of this file not. */ |
| 92 | int |
| 93 | res_init(void) { |
| 94 | extern int __res_vinit(res_state, int); |
| 95 | |
| 96 | /* |
| 97 | * These three fields used to be statically initialized. This made |
| 98 | * it hard to use this code in a shared library. It is necessary, |
| 99 | * now that we're doing dynamic initialization here, that we preserve |
| 100 | * the old semantics: if an application modifies one of these three |
| 101 | * fields of _res before res_init() is called, res_init() will not |
| 102 | * alter them. Of course, if an application is setting them to |
| 103 | * _zero_ before calling res_init(), hoping to override what used |
| 104 | * to be the static default, we can't detect it and unexpected results |
| 105 | * will follow. Zero for any of these fields would make no sense, |
| 106 | * so one can safely assume that the applications were already getting |
| 107 | * unexpected results. |
| 108 | * |
| 109 | * _res.options is tricky since some apps were known to diddle the bits |
| 110 | * before res_init() was first called. We can't replicate that semantic |
| 111 | * with dynamic initialization (they may have turned bits off that are |
| 112 | * set in RES_DEFAULT). Our solution is to declare such applications |
| 113 | * "broken". They could fool us by setting RES_INIT but none do (yet). |
| 114 | */ |
| 115 | if (!_res.retrans) |
| 116 | _res.retrans = RES_TIMEOUT; |
| 117 | if (!_res.retry) |
| 118 | _res.retry = 4; |
| 119 | if (!(_res.options & RES_INIT)) |
| 120 | _res.options = RES_DEFAULT; |
| 121 | |
| 122 | /* |
| 123 | * This one used to initialize implicitly to zero, so unless the app |
| 124 | * has set it to something in particular, we can randomize it now. |
| 125 | */ |
| 126 | if (!_res.id) |
| 127 | _res.id = res_randomid(); |
| 128 | |
| 129 | return (__res_vinit(&_res, 1)); |
| 130 | } |
| 131 | #endif |
| 132 | |
| 133 | void |
| 134 | p_query(const u_char *msg) { |
| 135 | fp_query(msg, stdout); |
| 136 | } |
| 137 | |
| 138 | void |
| 139 | fp_query(const u_char *msg, FILE *file) { |
| 140 | fp_nquery(msg, PACKETSZ, file); |
| 141 | } |
| 142 | libresolv_hidden_def (fp_query) |
| 143 | |
| 144 | void |
| 145 | fp_nquery(const u_char *msg, int len, FILE *file) { |
| 146 | if (__res_maybe_init (&_res, 0) == -1) |
| 147 | return; |
| 148 | |
| 149 | res_pquery(&_res, msg, len, file); |
| 150 | } |
| 151 | libresolv_hidden_def (fp_nquery) |
| 152 | |
| 153 | int |
| 154 | res_mkquery(int op, /* opcode of query */ |
| 155 | const char *dname, /* domain name */ |
| 156 | int class, int type, /* class and type of query */ |
| 157 | const u_char *data, /* resource record data */ |
| 158 | int datalen, /* length of data */ |
| 159 | const u_char *newrr_in, /* new rr for modify or append */ |
| 160 | u_char *buf, /* buffer to put query */ |
| 161 | int buflen) /* size of buffer */ |
| 162 | { |
| 163 | if (__res_maybe_init (&_res, 1) == -1) { |
| 164 | RES_SET_H_ERRNO(&_res, NETDB_INTERNAL); |
| 165 | return (-1); |
| 166 | } |
| 167 | return (res_nmkquery(&_res, op, dname, class, type, |
| 168 | data, datalen, |
| 169 | newrr_in, buf, buflen)); |
| 170 | } |
| 171 | |
| 172 | #ifdef BIND_UPDATE |
| 173 | int |
| 174 | res_mkupdate(ns_updrec *rrecp_in, u_char *buf, int buflen) { |
| 175 | if (__res_maybe_init (&_res, 1) == -1) { |
| 176 | RES_SET_H_ERRNO(&_res, NETDB_INTERNAL); |
| 177 | return (-1); |
| 178 | } |
| 179 | |
| 180 | return (res_nmkupdate(&_res, rrecp_in, buf, buflen)); |
| 181 | } |
| 182 | #endif |
| 183 | |
| 184 | int |
| 185 | res_query(const char *name, /* domain name */ |
| 186 | int class, int type, /* class and type of query */ |
| 187 | u_char *answer, /* buffer to put answer */ |
| 188 | int anslen) /* size of answer buffer */ |
| 189 | { |
| 190 | if (__res_maybe_init (&_res, 1) == -1) { |
| 191 | RES_SET_H_ERRNO(&_res, NETDB_INTERNAL); |
| 192 | return (-1); |
| 193 | } |
| 194 | return (res_nquery(&_res, name, class, type, answer, anslen)); |
| 195 | } |
| 196 | |
| 197 | void |
| 198 | res_send_setqhook(res_send_qhook hook) { |
| 199 | _res.qhook = hook; |
| 200 | } |
| 201 | |
| 202 | void |
| 203 | res_send_setrhook(res_send_rhook hook) { |
| 204 | _res.rhook = hook; |
| 205 | } |
| 206 | |
| 207 | int |
| 208 | res_isourserver(const struct sockaddr_in *inp) { |
| 209 | return (res_ourserver_p(&_res, (const struct sockaddr_in6 *) inp)); |
| 210 | } |
| 211 | |
| 212 | int |
| 213 | res_send(const u_char *buf, int buflen, u_char *ans, int anssiz) { |
| 214 | if (__res_maybe_init (&_res, 1) == -1) { |
| 215 | /* errno should have been set by res_init() in this case. */ |
| 216 | return (-1); |
| 217 | } |
| 218 | |
| 219 | return (res_nsend(&_res, buf, buflen, ans, anssiz)); |
| 220 | } |
| 221 | |
| 222 | #ifndef _LIBC |
| 223 | int |
| 224 | res_sendsigned(const u_char *buf, int buflen, ns_tsig_key *key, |
| 225 | u_char *ans, int anssiz) |
| 226 | { |
| 227 | if (__res_maybe_init (&_res, 1) == -1) { |
| 228 | /* errno should have been set by res_init() in this case. */ |
| 229 | return (-1); |
| 230 | } |
| 231 | |
| 232 | return (res_nsendsigned(&_res, buf, buflen, key, ans, anssiz)); |
| 233 | } |
| 234 | #endif |
| 235 | |
| 236 | void |
| 237 | res_close(void) { |
| 238 | #ifdef _LIBC |
| 239 | /* |
| 240 | * Some stupid programs out there call res_close() before res_init(). |
| 241 | * Since _res._vcsock isn't explicitly initialized, these means that |
| 242 | * we could do a close(0), which might lead to some security problems. |
| 243 | * Therefore we check if res_init() was called before by looking at |
| 244 | * the RES_INIT bit in _res.options. If it hasn't been set we bail out |
| 245 | * early. */ |
| 246 | if ((_res.options & RES_INIT) == 0) |
| 247 | return; |
| 248 | #endif |
| 249 | /* We don't free the name server addresses because we never |
| 250 | did it and it would be done implicitly on shutdown. */ |
| 251 | __res_iclose(&_res, false); |
| 252 | } |
| 253 | |
| 254 | #ifdef BIND_UPDATE |
| 255 | int |
| 256 | res_update(ns_updrec *rrecp_in) { |
| 257 | if (__res_maybe_init (&_res, 1) == -1) { |
| 258 | RES_SET_H_ERRNO(&_res, NETDB_INTERNAL); |
| 259 | return (-1); |
| 260 | } |
| 261 | |
| 262 | return (res_nupdate(&_res, rrecp_in, NULL)); |
| 263 | } |
| 264 | #endif |
| 265 | |
| 266 | int |
| 267 | res_search(const char *name, /* domain name */ |
| 268 | int class, int type, /* class and type of query */ |
| 269 | u_char *answer, /* buffer to put answer */ |
| 270 | int anslen) /* size of answer */ |
| 271 | { |
| 272 | if (__res_maybe_init (&_res, 1) == -1) { |
| 273 | RES_SET_H_ERRNO(&_res, NETDB_INTERNAL); |
| 274 | return (-1); |
| 275 | } |
| 276 | |
| 277 | return (res_nsearch(&_res, name, class, type, answer, anslen)); |
| 278 | } |
| 279 | |
| 280 | int |
| 281 | res_querydomain(const char *name, |
| 282 | const char *domain, |
| 283 | int class, int type, /* class and type of query */ |
| 284 | u_char *answer, /* buffer to put answer */ |
| 285 | int anslen) /* size of answer */ |
| 286 | { |
| 287 | if (__res_maybe_init (&_res, 1) == -1) { |
| 288 | RES_SET_H_ERRNO(&_res, NETDB_INTERNAL); |
| 289 | return (-1); |
| 290 | } |
| 291 | |
| 292 | return (res_nquerydomain(&_res, name, domain, |
| 293 | class, type, |
| 294 | answer, anslen)); |
| 295 | } |
| 296 | |
| 297 | const char * |
| 298 | hostalias(const char *name) { |
| 299 | static char abuf[MAXDNAME]; |
| 300 | |
| 301 | return (res_hostalias(&_res, name, abuf, sizeof abuf)); |
| 302 | } |
| 303 | libresolv_hidden_def (hostalias) |
| 304 | |
| 305 | #ifdef ultrix |
| 306 | int |
| 307 | local_hostname_length(const char *hostname) { |
| 308 | int len_host, len_domain; |
| 309 | |
| 310 | if (!*_res.defdname) |
| 311 | res_init(); |
| 312 | len_host = strlen(hostname); |
| 313 | len_domain = strlen(_res.defdname); |
| 314 | if (len_host > len_domain && |
| 315 | !strcasecmp(hostname + len_host - len_domain, _res.defdname) && |
| 316 | hostname[len_host - len_domain - 1] == '.') |
| 317 | return (len_host - len_domain - 1); |
| 318 | return (0); |
| 319 | } |
| 320 | #endif /*ultrix*/ |
| 321 | |
| 322 | #endif |
| 323 | |
| 324 | |
| 325 | #include <shlib-compat.h> |
| 326 | |
| 327 | #if SHLIB_COMPAT(libresolv, GLIBC_2_0, GLIBC_2_2) |
| 328 | # undef res_mkquery |
| 329 | # undef res_query |
| 330 | # undef res_querydomain |
| 331 | # undef res_search |
| 332 | weak_alias (__res_mkquery, res_mkquery); |
| 333 | weak_alias (__res_query, res_query); |
| 334 | weak_alias (__res_querydomain, res_querydomain); |
| 335 | weak_alias (__res_search, res_search); |
| 336 | #endif |