freebsd-dev/lib/libc/net/gethostbyht.c
Dmitrij Tejblum 141894af60 Ensure that host_addr (which is returned in struct hostent::h_addr_list[0])
is aligned so that pointer to it can be safely casted to struct in_addr *.
1999-06-07 16:30:27 +00:00

203 lines
5.7 KiB
C

/*-
* 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. All advertising materials mentioning features or use of this software
* must display the following acknowledgement:
* This product includes software developed by the University of
* California, Berkeley and its contributors.
* 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.
* -
* --Copyright--
*/
#if defined(LIBC_SCCS) && !defined(lint)
static char sccsid[] = "@(#)gethostnamadr.c 8.1 (Berkeley) 6/4/93";
static char rcsid[] = "$Id: gethostbyht.c,v 1.10 1997/06/27 08:22:01 peter Exp $";
#endif /* LIBC_SCCS and not lint */
#include <sys/param.h>
#include <sys/socket.h>
#include <netinet/in.h>
#include <arpa/inet.h>
#include <netdb.h>
#include <stdio.h>
#include <ctype.h>
#include <errno.h>
#include <string.h>
#include <arpa/nameser.h> /* XXX */
#include <resolv.h> /* XXX */
#define MAXALIASES 35
static struct hostent host;
static char *host_aliases[MAXALIASES];
static char hostbuf[BUFSIZ+1];
static FILE *hostf = NULL;
static u_int32_t host_addr[4]; /* IPv4 or IPv6 */
static char *h_addr_ptrs[2];
static int stayopen = 0;
void
_sethosthtent(f)
int f;
{
if (!hostf)
hostf = fopen(_PATH_HOSTS, "r" );
else
rewind(hostf);
stayopen = f;
}
void
_endhosthtent()
{
if (hostf && !stayopen) {
(void) fclose(hostf);
hostf = NULL;
}
}
struct hostent *
gethostent()
{
char *p;
register char *cp, **q;
int af, len;
if (!hostf && !(hostf = fopen(_PATH_HOSTS, "r" ))) {
h_errno = NETDB_INTERNAL;
return (NULL);
}
again:
if (!(p = fgets(hostbuf, sizeof hostbuf, hostf))) {
h_errno = HOST_NOT_FOUND;
return (NULL);
}
if (*p == '#')
goto again;
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 = IN6ADDRSZ;
} else if (inet_pton(AF_INET, p, host_addr) > 0) {
if (_res.options & RES_USE_INET6) {
_map_v4v6_address((char*)host_addr, (char*)host_addr);
af = AF_INET6;
len = IN6ADDRSZ;
} else {
af = AF_INET;
len = INADDRSZ;
}
} else {
goto again;
}
h_addr_ptrs[0] = (char *)host_addr;
h_addr_ptrs[1] = NULL;
host.h_addr_list = h_addr_ptrs;
host.h_length = len;
host.h_addrtype = af;
while (*cp == ' ' || *cp == '\t')
cp++;
host.h_name = cp;
q = host.h_aliases = host_aliases;
if ((cp = strpbrk(cp, " \t")) != NULL)
*cp++ = '\0';
while (cp && *cp) {
if (*cp == ' ' || *cp == '\t') {
cp++;
continue;
}
if (q < &host_aliases[MAXALIASES - 1])
*q++ = cp;
if ((cp = strpbrk(cp, " \t")) != NULL)
*cp++ = '\0';
}
*q = NULL;
h_errno = NETDB_SUCCESS;
return (&host);
}
struct hostent *
_gethostbyhtname(name, af)
const char *name;
int af;
{
register struct hostent *p;
register char **cp;
sethostent(0);
while ((p = gethostent()) != NULL) {
if (p->h_addrtype != af)
continue;
if (strcasecmp(p->h_name, name) == 0)
break;
for (cp = p->h_aliases; *cp != 0; cp++)
if (strcasecmp(*cp, name) == 0)
goto found;
}
found:
endhostent();
return (p);
}
struct hostent *
_gethostbyhtaddr(addr, len, af)
const char *addr;
int len, af;
{
register struct hostent *p;
sethostent(0);
while ((p = gethostent()) != NULL)
if (p->h_addrtype == af && !bcmp(p->h_addr, addr, len))
break;
endhostent();
return (p);
}