NetBSD/distrib/utils/libhack/gethost.c

233 lines
6.5 KiB
C

/* $NetBSD: gethost.c,v 1.12 2013/12/21 20:10:02 christos Exp $ */
/*-
* Copyright (c) 1985, 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.
* 3. 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.
* -
* --Copyright--
*/
/* Provide just /etc/hosts lookup support */
#include <sys/cdefs.h>
#ifdef __weak_alias
#define gethostbyaddr _gethostbyaddr
#define gethostbyname _gethostbyname
#endif
#include <netdb.h>
#include <string.h>
#include <nsswitch.h>
#include <errno.h>
#include <arpa/nameser.h>
#include <arpa/inet.h>
#include <sys/socket.h>
#include "hostent.h"
#ifdef __weak_alias
__weak_alias(gethostbyaddr,_gethostbyaddr);
__weak_alias(gethostbyname,_gethostbyname);
#endif
int h_errno;
FILE *_h_file;
static struct hostent h_ent;
static char h_buf[4096];
static struct hostent *
getby(int (*f)(void *, void *, va_list), struct getnamaddr *info, ...)
{
va_list ap;
int e;
va_start(ap, info);
e = (*f)(info, NULL, ap);
va_end(ap);
switch (e) {
case NS_SUCCESS:
return info->hp;
default:
return NULL;
}
}
struct hostent *
gethostbyname_r(const char *name, struct hostent *hp, char *buf, size_t bufsiz,
int *he)
{
struct getnamaddr info;
info.hp = hp;
info.buf = buf;
info.buflen = bufsiz;
info.he = he;
return getby(_hf_gethtbyname, &info, name, 0, AF_INET);
}
struct hostent *
gethostbyname(const char *name)
{
return gethostbyname_r(name, &h_ent, h_buf, sizeof(h_buf), &h_errno);
}
struct hostent *
gethostbyaddr_r(const void *addr, socklen_t len, int type, struct hostent *hp,
char *buf, size_t bufsiz, int *he)
{
struct getnamaddr info;
info.hp = hp;
info.buf = buf;
info.buflen = bufsiz;
info.he = he;
return getby(_hf_gethtbyaddr, &info, addr, len, type);
}
struct hostent *
gethostbyaddr(const void *addr, socklen_t len, int type)
{
return gethostbyaddr_r(addr, len, type, &h_ent, h_buf, sizeof(h_buf),
&h_errno);
}
struct hostent *
gethostent_r(FILE *hf, struct hostent *hent, char *buf, size_t buflen, int *he)
{
char *p, *name;
char *cp, **q;
int af, len;
size_t llen, anum;
char *aliases[MAXALIASES];
struct in6_addr host_addr;
if (hf == NULL) {
*he = NETDB_INTERNAL;
errno = EINVAL;
return NULL;
}
again:
if ((p = fgetln(hf, &llen)) == NULL) {
*he = HOST_NOT_FOUND;
return NULL;
}
if (llen < 1)
goto again;
if (*p == '#')
goto again;
p[llen] = '\0';
if (!(cp = strpbrk(p, "#\n")))
goto again;
*cp = '\0';
if (!(cp = strpbrk(p, " \t")))
goto again;
*cp++ = '\0';
if (inet_pton(AF_INET6, p, &host_addr) > 0) {
af = AF_INET6;
len = NS_IN6ADDRSZ;
} else if (inet_pton(AF_INET, p, &host_addr) > 0) {
#if 0
res_state res = __res_get_state();
if (res == NULL)
return NULL;
if (res->options & RES_USE_INET6) {
map_v4v6_address(buf, buf);
af = AF_INET6;
len = NS_IN6ADDRSZ;
} else {
#endif
af = AF_INET;
len = NS_INADDRSZ;
#if 0
}
__res_put_state(res);
#endif
} else {
goto again;
}
/* if this is not something we're looking for, skip it. */
if (hent->h_addrtype != 0 && hent->h_addrtype != af)
goto again;
if (hent->h_length != 0 && hent->h_length != len)
goto again;
while (*cp == ' ' || *cp == '\t')
cp++;
if ((cp = strpbrk(name = cp, " \t")) != NULL)
*cp++ = '\0';
q = aliases;
while (cp && *cp) {
if (*cp == ' ' || *cp == '\t') {
cp++;
continue;
}
if (q >= &aliases[__arraycount(aliases)])
goto nospc;
*q++ = cp;
if ((cp = strpbrk(cp, " \t")) != NULL)
*cp++ = '\0';
}
hent->h_length = len;
hent->h_addrtype = af;
HENT_ARRAY(hent->h_addr_list, 1, buf, buflen);
anum = (size_t)(q - aliases);
HENT_ARRAY(hent->h_aliases, anum, buf, buflen);
HENT_COPY(hent->h_addr_list[0], &host_addr, hent->h_length, buf,
buflen);
hent->h_addr_list[1] = NULL;
HENT_SCOPY(hent->h_name, name, buf, buflen);
for (size_t i = 0; i < anum; i++)
HENT_SCOPY(hent->h_aliases[i], aliases[i], buf, buflen);
hent->h_aliases[anum] = NULL;
*he = NETDB_SUCCESS;
return hent;
nospc:
errno = ENOSPC;
*he = NETDB_INTERNAL;
return NULL;
}