diff options
Diffstat (limited to 'resolv/res_query.c')
| -rw-r--r-- | resolv/res_query.c | 649 |
1 files changed, 0 insertions, 649 deletions
diff --git a/resolv/res_query.c b/resolv/res_query.c deleted file mode 100644 index 0ca3a65028..0000000000 --- a/resolv/res_query.c +++ /dev/null @@ -1,649 +0,0 @@ -/* - * Copyright (c) 1988, 1993 - * The Regents of the University of California. All rights reserved. - * - * Redistribution and use in source and binary forms, with or without - * modification, are permitted provided that the following conditions - * are met: - * 1. Redistributions of source code must retain the above copyright - * notice, this list of conditions and the following disclaimer. - * 2. Redistributions in binary form must reproduce the above copyright - * notice, this list of conditions and the following disclaimer in the - * documentation and/or other materials provided with the distribution. - * 4. Neither the name of the University nor the names of its contributors - * may be used to endorse or promote products derived from this software - * without specific prior written permission. - * - * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND - * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE - * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE - * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE - * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL - * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS - * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) - * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT - * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY - * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF - * SUCH DAMAGE. - */ - -/* - * Portions Copyright (c) 1993 by Digital Equipment Corporation. - * - * Permission to use, copy, modify, and distribute this software for any - * purpose with or without fee is hereby granted, provided that the above - * copyright notice and this permission notice appear in all copies, and that - * the name of Digital Equipment Corporation not be used in advertising or - * publicity pertaining to distribution of the document or software without - * specific, written prior permission. - * - * THE SOFTWARE IS PROVIDED "AS IS" AND DIGITAL EQUIPMENT CORP. DISCLAIMS ALL - * WARRANTIES WITH REGARD TO THIS SOFTWARE, INCLUDING ALL IMPLIED WARRANTIES - * OF MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL DIGITAL EQUIPMENT - * CORPORATION BE LIABLE FOR ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL - * DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR - * PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS - * ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS - * SOFTWARE. - */ - -/* - * Portions Copyright (c) 1996-1999 by Internet Software Consortium. - * - * Permission to use, copy, modify, and distribute this software for any - * purpose with or without fee is hereby granted, provided that the above - * copyright notice and this permission notice appear in all copies. - * - * THE SOFTWARE IS PROVIDED "AS IS" AND INTERNET SOFTWARE CONSORTIUM DISCLAIMS - * ALL WARRANTIES WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES - * OF MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL INTERNET SOFTWARE - * CONSORTIUM BE LIABLE FOR ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL - * DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR - * PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS - * ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS - * SOFTWARE. - */ - -#include <assert.h> -#include <sys/types.h> -#include <sys/param.h> -#include <netinet/in.h> -#include <arpa/inet.h> -#include <arpa/nameser.h> -#include <ctype.h> -#include <errno.h> -#include <netdb.h> -#include <resolv.h> -#include <resolv/resolv-internal.h> -#include <stdio.h> -#include <stdlib.h> -#include <string.h> -#include <resolv/resolv-internal.h> - -/* Options. Leave them on. */ -/* #undef DEBUG */ - -#if PACKETSZ > 65536 -#define MAXPACKET PACKETSZ -#else -#define MAXPACKET 65536 -#endif - -#define QUERYSIZE (HFIXEDSZ + QFIXEDSZ + MAXCDNAME + 1) - -static int -__libc_res_nquerydomain(res_state statp, const char *name, const char *domain, - int class, int type, u_char *answer, int anslen, - u_char **answerp, u_char **answerp2, int *nanswerp2, - int *resplen2, int *answerp2_malloced); - -/* - * Formulate a normal query, send, and await answer. - * Returned answer is placed in supplied buffer "answer". - * Perform preliminary check of answer, returning success only - * if no error is indicated and the answer count is nonzero. - * Return the size of the response on success, -1 on error. - * Error number is left in H_ERRNO. - * - * Caller must parse answer and determine whether it answers the question. - */ -int -__libc_res_nquery(res_state statp, - const char *name, /* domain name */ - int class, int type, /* class and type of query */ - u_char *answer, /* buffer to put answer */ - int anslen, /* size of answer buffer */ - u_char **answerp, /* if buffer needs to be enlarged */ - u_char **answerp2, - int *nanswerp2, - int *resplen2, - int *answerp2_malloced) -{ - HEADER *hp = (HEADER *) answer; - HEADER *hp2; - int n, use_malloc = 0; - - size_t bufsize = (type == T_QUERY_A_AND_AAAA ? 2 : 1) * QUERYSIZE; - u_char *buf = alloca (bufsize); - u_char *query1 = buf; - int nquery1 = -1; - u_char *query2 = NULL; - int nquery2 = 0; - - again: - hp->rcode = NOERROR; /* default */ - -#ifdef DEBUG - if (statp->options & RES_DEBUG) - printf(";; res_query(%s, %d, %d)\n", name, class, type); -#endif - - if (type == T_QUERY_A_AND_AAAA) - { - n = res_nmkquery(statp, QUERY, name, class, T_A, NULL, 0, NULL, - query1, bufsize); - if (n > 0) - { - if ((statp->options & (RES_USE_EDNS0|RES_USE_DNSSEC)) != 0) - { - /* Use RESOLV_EDNS_BUFFER_SIZE because the receive - buffer can be reallocated. */ - n = __res_nopt (statp, n, query1, bufsize, - RESOLV_EDNS_BUFFER_SIZE); - if (n < 0) - goto unspec_nomem; - } - - nquery1 = n; - /* Align the buffer. */ - int npad = ((nquery1 + __alignof__ (HEADER) - 1) - & ~(__alignof__ (HEADER) - 1)) - nquery1; - if (n > bufsize - npad) - { - n = -1; - goto unspec_nomem; - } - int nused = n + npad; - query2 = buf + nused; - n = res_nmkquery(statp, QUERY, name, class, T_AAAA, NULL, 0, - NULL, query2, bufsize - nused); - if (n > 0 - && (statp->options & (RES_USE_EDNS0|RES_USE_DNSSEC)) != 0) - /* Use RESOLV_EDNS_BUFFER_SIZE because the receive - buffer can be reallocated. */ - n = __res_nopt (statp, n, query2, bufsize, - RESOLV_EDNS_BUFFER_SIZE); - nquery2 = n; - } - - unspec_nomem:; - } - else - { - n = res_nmkquery(statp, QUERY, name, class, type, NULL, 0, NULL, - query1, bufsize); - - if (n > 0 - && (statp->options & (RES_USE_EDNS0|RES_USE_DNSSEC)) != 0) - { - /* Use RESOLV_EDNS_BUFFER_SIZE if the receive buffer - can be reallocated. */ - size_t advertise; - if (answerp == NULL) - advertise = anslen; - else - advertise = RESOLV_EDNS_BUFFER_SIZE; - n = __res_nopt (statp, n, query1, bufsize, advertise); - } - - nquery1 = n; - } - - if (__glibc_unlikely (n <= 0) && !use_malloc) { - /* Retry just in case res_nmkquery failed because of too - short buffer. Shouldn't happen. */ - bufsize = (type == T_QUERY_A_AND_AAAA ? 2 : 1) * MAXPACKET; - buf = malloc (bufsize); - if (buf != NULL) { - query1 = buf; - use_malloc = 1; - goto again; - } - } - if (__glibc_unlikely (n <= 0)) { -#ifdef DEBUG - if (statp->options & RES_DEBUG) - printf(";; res_query: mkquery failed\n"); -#endif - RES_SET_H_ERRNO(statp, NO_RECOVERY); - if (use_malloc) - free (buf); - return (n); - } - assert (answerp == NULL || (void *) *answerp == (void *) answer); - n = __libc_res_nsend(statp, query1, nquery1, query2, nquery2, answer, - anslen, answerp, answerp2, nanswerp2, resplen2, - answerp2_malloced); - if (use_malloc) - free (buf); - if (n < 0) { -#ifdef DEBUG - if (statp->options & RES_DEBUG) - printf(";; res_query: send error\n"); -#endif - RES_SET_H_ERRNO(statp, TRY_AGAIN); - return (n); - } - - if (answerp != NULL) - /* __libc_res_nsend might have reallocated the buffer. */ - hp = (HEADER *) *answerp; - - /* We simplify the following tests by assigning HP to HP2 or - vice versa. It is easy to verify that this is the same as - ignoring all tests of HP or HP2. */ - if (answerp2 == NULL || *resplen2 < (int) sizeof (HEADER)) - { - hp2 = hp; - } - else - { - hp2 = (HEADER *) *answerp2; - if (n < (int) sizeof (HEADER)) - { - hp = hp2; - } - } - - /* Make sure both hp and hp2 are defined */ - assert((hp != NULL) && (hp2 != NULL)); - - if ((hp->rcode != NOERROR || ntohs(hp->ancount) == 0) - && (hp2->rcode != NOERROR || ntohs(hp2->ancount) == 0)) { -#ifdef DEBUG - if (statp->options & RES_DEBUG) { - printf(";; rcode = %d, ancount=%d\n", hp->rcode, - ntohs(hp->ancount)); - if (hp != hp2) - printf(";; rcode2 = %d, ancount2=%d\n", hp2->rcode, - ntohs(hp2->ancount)); - } -#endif - switch (hp->rcode == NOERROR ? hp2->rcode : hp->rcode) { - case NXDOMAIN: - if ((hp->rcode == NOERROR && ntohs (hp->ancount) != 0) - || (hp2->rcode == NOERROR - && ntohs (hp2->ancount) != 0)) - goto success; - RES_SET_H_ERRNO(statp, HOST_NOT_FOUND); - break; - case SERVFAIL: - RES_SET_H_ERRNO(statp, TRY_AGAIN); - break; - case NOERROR: - if (ntohs (hp->ancount) != 0 - || ntohs (hp2->ancount) != 0) - goto success; - RES_SET_H_ERRNO(statp, NO_DATA); - break; - case FORMERR: - case NOTIMP: - /* Servers must not reply to AAAA queries with - NOTIMP etc but some of them do. */ - if ((hp->rcode == NOERROR && ntohs (hp->ancount) != 0) - || (hp2->rcode == NOERROR - && ntohs (hp2->ancount) != 0)) - goto success; - /* FALLTHROUGH */ - case REFUSED: - default: - RES_SET_H_ERRNO(statp, NO_RECOVERY); - break; - } - return (-1); - } - success: - return (n); -} -libresolv_hidden_def (__libc_res_nquery) - -int -res_nquery(res_state statp, - const char *name, /* domain name */ - int class, int type, /* class and type of query */ - u_char *answer, /* buffer to put answer */ - int anslen) /* size of answer buffer */ -{ - return __libc_res_nquery(statp, name, class, type, answer, anslen, - NULL, NULL, NULL, NULL, NULL); -} -libresolv_hidden_def (res_nquery) - -/* - * Formulate a normal query, send, and retrieve answer in supplied buffer. - * Return the size of the response on success, -1 on error. - * If enabled, implement search rules until answer or unrecoverable failure - * is detected. Error code, if any, is left in H_ERRNO. - */ -int -__libc_res_nsearch(res_state statp, - const char *name, /* domain name */ - int class, int type, /* class and type of query */ - u_char *answer, /* buffer to put answer */ - int anslen, /* size of answer */ - u_char **answerp, - u_char **answerp2, - int *nanswerp2, - int *resplen2, - int *answerp2_malloced) -{ - const char *cp, * const *domain; - HEADER *hp = (HEADER *) answer; - char tmp[NS_MAXDNAME]; - u_int dots; - int trailing_dot, ret, saved_herrno; - int got_nodata = 0, got_servfail = 0, root_on_list = 0; - int tried_as_is = 0; - int searched = 0; - - __set_errno (0); - RES_SET_H_ERRNO(statp, HOST_NOT_FOUND); /* True if we never query. */ - - dots = 0; - for (cp = name; *cp != '\0'; cp++) - dots += (*cp == '.'); - trailing_dot = 0; - if (cp > name && *--cp == '.') - trailing_dot++; - - /* If there aren't any dots, it could be a user-level alias. */ - if (!dots && (cp = res_hostalias(statp, name, tmp, sizeof tmp))!= NULL) - return (__libc_res_nquery(statp, cp, class, type, answer, - anslen, answerp, answerp2, - nanswerp2, resplen2, answerp2_malloced)); - -#ifdef DEBUG - if (statp->options & RES_DEBUG) - printf("dots=%d, statp->ndots=%d, trailing_dot=%d, name=%s\n", - (int)dots,(int)statp->ndots,(int)trailing_dot,name); -#endif - - /* - * If there are enough dots in the name, let's just give it a - * try 'as is'. The threshold can be set with the "ndots" option. - * Also, query 'as is', if there is a trailing dot in the name. - */ - saved_herrno = -1; - if (dots >= statp->ndots || trailing_dot) { - ret = __libc_res_nquerydomain(statp, name, NULL, class, type, - answer, anslen, answerp, - answerp2, nanswerp2, resplen2, - answerp2_malloced); - if (ret > 0 || trailing_dot - /* If the second response is valid then we use that. */ - || (ret == 0 && resplen2 != NULL && *resplen2 > 0)) - return (ret); - saved_herrno = h_errno; - tried_as_is++; - if (answerp && *answerp != answer) { - answer = *answerp; - anslen = MAXPACKET; - } - if (answerp2 && *answerp2_malloced) - { - free (*answerp2); - *answerp2 = NULL; - *nanswerp2 = 0; - *answerp2_malloced = 0; - } - } - - /* - * We do at least one level of search if - * - there is no dot and RES_DEFNAME is set, or - * - there is at least one dot, there is no trailing dot, - * and RES_DNSRCH is set. - */ - if ((!dots && (statp->options & RES_DEFNAMES) != 0) || - (dots && !trailing_dot && (statp->options & RES_DNSRCH) != 0)) { - int done = 0; - - for (domain = (const char * const *)statp->dnsrch; - *domain && !done; - domain++) { - const char *dname = domain[0]; - searched = 1; - - /* __libc_res_nquerydoman concatenates name - with dname with a "." in between. If we - pass it in dname the "." we got from the - configured default search path, we'll end - up with "name..", which won't resolve. - OTOH, passing it "" will result in "name.", - which has the intended effect for both - possible representations of the root - domain. */ - if (dname[0] == '.') - dname++; - if (dname[0] == '\0') - root_on_list++; - - ret = __libc_res_nquerydomain(statp, name, dname, - class, type, - answer, anslen, answerp, - answerp2, nanswerp2, - resplen2, answerp2_malloced); - if (ret > 0 || (ret == 0 && resplen2 != NULL - && *resplen2 > 0)) - return (ret); - - if (answerp && *answerp != answer) { - answer = *answerp; - anslen = MAXPACKET; - } - if (answerp2 && *answerp2_malloced) - { - free (*answerp2); - *answerp2 = NULL; - *nanswerp2 = 0; - *answerp2_malloced = 0; - } - - /* - * If no server present, give up. - * If name isn't found in this domain, - * keep trying higher domains in the search list - * (if that's enabled). - * On a NO_DATA error, keep trying, otherwise - * a wildcard entry of another type could keep us - * from finding this entry higher in the domain. - * If we get some other error (negative answer or - * server failure), then stop searching up, - * but try the input name below in case it's - * fully-qualified. - */ - if (errno == ECONNREFUSED) { - RES_SET_H_ERRNO(statp, TRY_AGAIN); - return (-1); - } - - switch (statp->res_h_errno) { - case NO_DATA: - got_nodata++; - /* FALLTHROUGH */ - case HOST_NOT_FOUND: - /* keep trying */ - break; - case TRY_AGAIN: - if (hp->rcode == SERVFAIL) { - /* try next search element, if any */ - got_servfail++; - break; - } - /* FALLTHROUGH */ - default: - /* anything else implies that we're done */ - done++; - } - - /* if we got here for some reason other than DNSRCH, - * we only wanted one iteration of the loop, so stop. - */ - if ((statp->options & RES_DNSRCH) == 0) - done++; - } - } - - /* - * If the query has not already been tried as is then try it - * unless RES_NOTLDQUERY is set and there were no dots. - */ - if ((dots || !searched || (statp->options & RES_NOTLDQUERY) == 0) - && !(tried_as_is || root_on_list)) { - ret = __libc_res_nquerydomain(statp, name, NULL, class, type, - answer, anslen, answerp, - answerp2, nanswerp2, resplen2, - answerp2_malloced); - if (ret > 0 || (ret == 0 && resplen2 != NULL - && *resplen2 > 0)) - return (ret); - } - - /* if we got here, we didn't satisfy the search. - * if we did an initial full query, return that query's H_ERRNO - * (note that we wouldn't be here if that query had succeeded). - * else if we ever got a nodata, send that back as the reason. - * else send back meaningless H_ERRNO, that being the one from - * the last DNSRCH we did. - */ - if (answerp2 && *answerp2_malloced) - { - free (*answerp2); - *answerp2 = NULL; - *nanswerp2 = 0; - *answerp2_malloced = 0; - } - if (saved_herrno != -1) - RES_SET_H_ERRNO(statp, saved_herrno); - else if (got_nodata) - RES_SET_H_ERRNO(statp, NO_DATA); - else if (got_servfail) - RES_SET_H_ERRNO(statp, TRY_AGAIN); - return (-1); -} -libresolv_hidden_def (__libc_res_nsearch) - -int -res_nsearch(res_state statp, - const char *name, /* domain name */ - int class, int type, /* class and type of query */ - u_char *answer, /* buffer to put answer */ - int anslen) /* size of answer */ -{ - return __libc_res_nsearch(statp, name, class, type, answer, - anslen, NULL, NULL, NULL, NULL, NULL); -} -libresolv_hidden_def (res_nsearch) - -/* - * Perform a call on res_query on the concatenation of name and domain. - */ -static int -__libc_res_nquerydomain(res_state statp, - const char *name, - const char *domain, - int class, int type, /* class and type of query */ - u_char *answer, /* buffer to put answer */ - int anslen, /* size of answer */ - u_char **answerp, - u_char **answerp2, - int *nanswerp2, - int *resplen2, - int *answerp2_malloced) -{ - char nbuf[MAXDNAME]; - const char *longname = nbuf; - size_t n, d; - -#ifdef DEBUG - if (statp->options & RES_DEBUG) - printf(";; res_nquerydomain(%s, %s, %d, %d)\n", - name, domain?domain:"<Nil>", class, type); -#endif - if (domain == NULL) { - n = strlen(name); - - /* Decrement N prior to checking it against MAXDNAME - so that we detect a wrap to SIZE_MAX and return - a reasonable error. */ - n--; - if (n >= MAXDNAME - 1) { - RES_SET_H_ERRNO(statp, NO_RECOVERY); - return (-1); - } - longname = name; - } else { - n = strlen(name); - d = strlen(domain); - if (n + d + 1 >= MAXDNAME) { - RES_SET_H_ERRNO(statp, NO_RECOVERY); - return (-1); - } - sprintf(nbuf, "%s.%s", name, domain); - } - return (__libc_res_nquery(statp, longname, class, type, answer, - anslen, answerp, answerp2, nanswerp2, - resplen2, answerp2_malloced)); -} - -int -res_nquerydomain(res_state statp, - const char *name, - const char *domain, - int class, int type, /* class and type of query */ - u_char *answer, /* buffer to put answer */ - int anslen) /* size of answer */ -{ - return __libc_res_nquerydomain(statp, name, domain, class, type, - answer, anslen, NULL, NULL, NULL, NULL, - NULL); -} -libresolv_hidden_def (res_nquerydomain) - -const char * -res_hostalias(const res_state statp, const char *name, char *dst, size_t siz) { - char *file, *cp1, *cp2; - char buf[BUFSIZ]; - FILE *fp; - - if (statp->options & RES_NOALIASES) - return (NULL); - file = getenv("HOSTALIASES"); - if (file == NULL || (fp = fopen(file, "rce")) == NULL) - return (NULL); - setbuf(fp, NULL); - buf[sizeof(buf) - 1] = '\0'; - while (fgets(buf, sizeof(buf), fp)) { - for (cp1 = buf; *cp1 && !isspace(*cp1); ++cp1) - ; - if (!*cp1) - break; - *cp1 = '\0'; - if (ns_samename(buf, name) == 1) { - while (isspace(*++cp1)) - ; - if (!*cp1) - break; - for (cp2 = cp1 + 1; *cp2 && !isspace(*cp2); ++cp2) - ; - *cp2 = '\0'; - strncpy(dst, cp1, siz - 1); - dst[siz - 1] = '\0'; - fclose(fp); - return (dst); - } - } - fclose(fp); - return (NULL); -} -libresolv_hidden_def (res_hostalias) |