glibc/resolv/res_data.c

332 lines
8.4 KiB
C
Raw Blame History

This file contains invisible Unicode characters

This file contains invisible Unicode characters that are indistinguishable to humans but may be processed differently by a computer. If you think that this is intentional, you can safely ignore this warning. Use the Escape button to reveal them.

/*
* Copyright (c) 1995-1999 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.
*/
#if defined(LIBC_SCCS) && !defined(lint)
static const char rcsid[] = "$BINDId: res_data.c,v 8.17 1999/10/13 17:11:31 vixie Exp $";
#endif /* LIBC_SCCS and not lint */
#include <sys/types.h>
#include <sys/param.h>
#include <sys/socket.h>
#include <sys/time.h>
#include <netinet/in.h>
#include <arpa/inet.h>
#include <arpa/nameser.h>
#include <ctype.h>
#include <netdb.h>
#include <resolv.h>
#ifdef BIND_UPDATE
#include <res_update.h>
#endif
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>
#undef _res
const char *_res_opcodes[] = {
"QUERY",
"IQUERY",
"CQUERYM",
"CQUERYU", /* experimental */
"NOTIFY", /* experimental */
"UPDATE",
"6",
"7",
"8",
"9",
"10",
"11",
"12",
"13",
"ZONEINIT",
"ZONEREF",
};
#ifdef BIND_UPDATE
const char *_res_sectioncodes[] = {
"ZONE",
"PREREQUISITES",
"UPDATE",
"ADDITIONAL",
};
#endif
#ifndef __BIND_NOSTATIC
#ifdef _LIBC
extern struct __res_state _res;
#else
/* The definition has been moved to res_libc.c. */
struct __res_state _res
# if defined(__BIND_RES_TEXT)
= { RES_TIMEOUT, } /* Motorola, et al. */
# endif
;
#endif
/* Proto. */
int res_ourserver_p(const res_state, const struct sockaddr_in *);
void res_pquery(const res_state, const u_char *, int, FILE *);
#ifndef _LIBC
/* Moved to res_libc.c since res_init() should go into libc.so but the
rest of this file not. */
int
res_init(void) {
extern int __res_vinit(res_state, int);
/*
* These three fields used to be statically initialized. This made
* it hard to use this code in a shared library. It is necessary,
* now that we're doing dynamic initialization here, that we preserve
* the old semantics: if an application modifies one of these three
* fields of _res before res_init() is called, res_init() will not
* alter them. Of course, if an application is setting them to
* _zero_ before calling res_init(), hoping to override what used
* to be the static default, we can't detect it and unexpected results
* will follow. Zero for any of these fields would make no sense,
* so one can safely assume that the applications were already getting
* unexpected results.
*
* _res.options is tricky since some apps were known to diddle the bits
* before res_init() was first called. We can't replicate that semantic
* with dynamic initialization (they may have turned bits off that are
* set in RES_DEFAULT). Our solution is to declare such applications
* "broken". They could fool us by setting RES_INIT but none do (yet).
*/
if (!_res.retrans)
_res.retrans = RES_TIMEOUT;
if (!_res.retry)
_res.retry = 4;
if (!(_res.options & RES_INIT))
_res.options = RES_DEFAULT;
/*
* This one used to initialize implicitly to zero, so unless the app
* has set it to something in particular, we can randomize it now.
*/
if (!_res.id)
_res.id = res_randomid();
return (__res_vinit(&_res, 1));
}
#endif
void
p_query(const u_char *msg) {
fp_query(msg, stdout);
}
void
fp_query(const u_char *msg, FILE *file) {
fp_nquery(msg, PACKETSZ, file);
}
void
fp_nquery(const u_char *msg, int len, FILE *file) {
if ((_res.options & RES_INIT) == 0 && res_init() == -1)
return;
res_pquery(&_res, msg, len, file);
}
int
res_mkquery(int op, /* opcode of query */
const char *dname, /* domain name */
int class, int type, /* class and type of query */
const u_char *data, /* resource record data */
int datalen, /* length of data */
const u_char *newrr_in, /* new rr for modify or append */
u_char *buf, /* buffer to put query */
int buflen) /* size of buffer */
{
if ((_res.options & RES_INIT) == 0 && res_init() == -1) {
RES_SET_H_ERRNO(&_res, NETDB_INTERNAL);
return (-1);
}
return (res_nmkquery(&_res, op, dname, class, type,
data, datalen,
newrr_in, buf, buflen));
}
#ifdef BIND_UPDATE
int
res_mkupdate(ns_updrec *rrecp_in, u_char *buf, int buflen) {
if ((_res.options & RES_INIT) == 0 && res_init() == -1) {
RES_SET_H_ERRNO(&_res, NETDB_INTERNAL);
return (-1);
}
return (res_nmkupdate(&_res, rrecp_in, buf, buflen));
}
#endif
int
res_query(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 */
{
if ((_res.options & RES_INIT) == 0 && res_init() == -1) {
RES_SET_H_ERRNO(&_res, NETDB_INTERNAL);
return (-1);
}
return (res_nquery(&_res, name, class, type, answer, anslen));
}
void
res_send_setqhook(res_send_qhook hook) {
_res.qhook = hook;
}
void
res_send_setrhook(res_send_rhook hook) {
_res.rhook = hook;
}
int
res_isourserver(const struct sockaddr_in *inp) {
return (res_ourserver_p(&_res, inp));
}
int
res_send(const u_char *buf, int buflen, u_char *ans, int anssiz) {
if ((_res.options & RES_INIT) == 0 && res_init() == -1) {
/* errno should have been set by res_init() in this case. */
return (-1);
}
return (res_nsend(&_res, buf, buflen, ans, anssiz));
}
#ifndef _LIBC
int
res_sendsigned(const u_char *buf, int buflen, ns_tsig_key *key,
u_char *ans, int anssiz)
{
if ((_res.options & RES_INIT) == 0 && res_init() == -1) {
/* errno should have been set by res_init() in this case. */
return (-1);
}
return (res_nsendsigned(&_res, buf, buflen, key, ans, anssiz));
}
#endif
void
res_close(void) {
#ifdef _LIBC
/*
* Some stupid programs out there call res_close() before res_init().
* Since _res._vcsock isn't explicitly initialized, these means that
* we could do a close(0), which might lead to some security problems.
* Therefore we check if res_init() was called before by looking at
* the RES_INIT bit in _res.options. If it hasn't been set we bail out
* early. */
if ((_res.options & RES_INIT) == 0)
return;
#endif
res_nclose(&_res);
}
#ifdef BIND_UPDATE
int
res_update(ns_updrec *rrecp_in) {
if ((_res.options & RES_INIT) == 0 && res_init() == -1) {
RES_SET_H_ERRNO(&_res, NETDB_INTERNAL);
return (-1);
}
return (res_nupdate(&_res, rrecp_in, NULL));
}
#endif
int
res_search(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 */
{
if ((_res.options & RES_INIT) == 0 && res_init() == -1) {
RES_SET_H_ERRNO(&_res, NETDB_INTERNAL);
return (-1);
}
return (res_nsearch(&_res, name, class, type, answer, anslen));
}
int
res_querydomain(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 */
{
if ((_res.options & RES_INIT) == 0 && res_init() == -1) {
RES_SET_H_ERRNO(&_res, NETDB_INTERNAL);
return (-1);
}
return (res_nquerydomain(&_res, name, domain,
class, type,
answer, anslen));
}
const char *
hostalias(const char *name) {
static char abuf[MAXDNAME];
return (res_hostalias(&_res, name, abuf, sizeof abuf));
}
#ifdef ultrix
int
local_hostname_length(const char *hostname) {
int len_host, len_domain;
if (!*_res.defdname)
res_init();
len_host = strlen(hostname);
len_domain = strlen(_res.defdname);
if (len_host > len_domain &&
!strcasecmp(hostname + len_host - len_domain, _res.defdname) &&
hostname[len_host - len_domain - 1] == '.')
return (len_host - len_domain - 1);
return (0);
}
#endif /*ultrix*/
#endif
#include <shlib-compat.h>
#if SHLIB_COMPAT(libresolv, GLIBC_2_0, GLIBC_2_2)
# undef res_mkquery
# undef res_query
# undef res_querydomain
# undef res_search
weak_alias (__res_mkquery, res_mkquery);
weak_alias (__res_query, res_query);
weak_alias (__res_querydomain, res_querydomain);
weak_alias (__res_search, res_search);
#endif