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|
/*-
* 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 rcsid[] = "$OpenBSD: gethostnamadr.c,v 1.39 1999/12/11 08:40:17 itojun Exp $";
#endif /* LIBC_SCCS and not lint */
#include <sys/param.h>
#include <sys/socket.h>
#include <netinet/in.h>
#include <arpa/inet.h>
#include <arpa/nameser.h>
#include <netdb.h>
#include <resolv.h>
#include <stdio.h>
#include <ctype.h>
#include <errno.h>
#include <string.h>
#include <syslog.h>
#include <stdlib.h>
#ifdef YP
#include <rpc/rpc.h>
#include <rpcsvc/yp.h>
#include <rpcsvc/ypclnt.h>
#include "ypinternal.h"
#endif
#include "thread_private.h"
#define MULTI_PTRS_ARE_ALIASES 1 /* XXX - experimental */
#define MAXALIASES 35
#define MAXADDRS 35
static char *h_addr_ptrs[MAXADDRS + 1];
#ifdef YP
static char *__ypdomain;
#endif
static struct hostent host;
static char *host_aliases[MAXALIASES];
static char hostbuf[BUFSIZ+1];
static union {
struct in_addr _host_in_addr;
u_char _host_addr[16]; /* IPv4 or IPv6 */
} _host_addr_u;
#define host_addr _host_addr_u._host_addr
static FILE *hostf = NULL;
static int stayopen = 0;
static void map_v4v6_address __P((const char *src, char *dst));
static void map_v4v6_hostent __P((struct hostent *hp, char **bp, int *len));
#ifdef RESOLVSORT
static void addrsort __P((char **, int));
#endif
int _hokchar __P((const char *));
static const char AskedForGot[] =
"gethostby*.getanswer: asked for \"%s\", got \"%s\"";
#if PACKETSZ > 1024
#define MAXPACKET PACKETSZ
#else
#define MAXPACKET 1024
#endif
typedef union {
HEADER hdr;
u_char buf[MAXPACKET];
} querybuf;
typedef union {
int32_t al;
char ac;
} align;
static struct hostent *getanswer __P((const querybuf *, int, const char *,
int));
extern int h_errno;
int
_hokchar(p)
const char *p;
{
char c;
/*
* Many people do not obey RFC 822 and 1035. The valid
* characters are a-z, A-Z, 0-9, '-' and . But the others
* tested for below can happen, and we must be more permissive
* than the resolver until those idiots clean up their act.
* We let '/' through, but not '..'
*/
while ((c = *p++)) {
if (('a' <= c && c <= 'z') ||
('A' <= c && c <= 'Z') ||
('0' <= c && c <= '9'))
continue;
if (strchr("-_/", c))
continue;
if (c == '.' && *p != '.')
continue;
return 0;
}
return 1;
}
static struct hostent *
getanswer(answer, anslen, qname, qtype)
const querybuf *answer;
int anslen;
const char *qname;
int qtype;
{
register const HEADER *hp;
register const u_char *cp;
register int n;
const u_char *eom;
char *bp, **ap, **hap;
int type, class, buflen, ancount, qdcount;
int haveanswer, had_error;
int toobig = 0;
char tbuf[MAXDNAME];
const char *tname;
int (*name_ok) __P((const char *));
tname = qname;
host.h_name = NULL;
eom = answer->buf + anslen;
switch (qtype) {
case T_A:
case T_AAAA:
#ifdef USE_RESOLV_NAME_OK
name_ok = res_hnok;
break;
#endif
case T_PTR:
#ifdef USE_RESOLV_NAME_OK
name_ok = res_dnok;
#else
name_ok = _hokchar;
#endif
break;
default:
return (NULL);
}
/*
* find first satisfactory answer
*/
hp = &answer->hdr;
ancount = ntohs(hp->ancount);
qdcount = ntohs(hp->qdcount);
bp = hostbuf;
buflen = sizeof hostbuf;
cp = answer->buf + HFIXEDSZ;
if (qdcount != 1) {
h_errno = NO_RECOVERY;
return (NULL);
}
n = dn_expand(answer->buf, eom, cp, bp, buflen);
if ((n < 0) || !(*name_ok)(bp)) {
h_errno = NO_RECOVERY;
return (NULL);
}
cp += n + QFIXEDSZ;
if (qtype == T_A || qtype == T_AAAA) {
/* res_send() has already verified that the query name is the
* same as the one we sent; this just gets the expanded name
* (i.e., with the succeeding search-domain tacked on).
*/
n = strlen(bp) + 1; /* for the \0 */
host.h_name = bp;
bp += n;
buflen -= n;
/* The qname can be abbreviated, but h_name is now absolute. */
qname = host.h_name;
}
ap = host_aliases;
*ap = NULL;
host.h_aliases = host_aliases;
hap = h_addr_ptrs;
*hap = NULL;
host.h_addr_list = h_addr_ptrs;
haveanswer = 0;
had_error = 0;
while (ancount-- > 0 && cp < eom && !had_error) {
n = dn_expand(answer->buf, eom, cp, bp, buflen);
if ((n < 0) || !(*name_ok)(bp)) {
had_error++;
continue;
}
cp += n; /* name */
type = _getshort(cp);
cp += INT16SZ; /* type */
class = _getshort(cp);
cp += INT16SZ + INT32SZ; /* class, TTL */
n = _getshort(cp);
cp += INT16SZ; /* len */
if (type == T_SIG) {
/* XXX - ignore signatures as we don't use them yet */
cp += n;
continue;
}
if (class != C_IN) {
/* XXX - debug? syslog? */
cp += n;
continue; /* XXX - had_error++ ? */
}
if ((qtype == T_A || qtype == T_AAAA) && type == T_CNAME) {
if (ap >= &host_aliases[MAXALIASES-1])
continue;
n = dn_expand(answer->buf, eom, cp, tbuf, sizeof tbuf);
if ((n < 0) || !(*name_ok)(tbuf)) {
had_error++;
continue;
}
cp += n;
/* Store alias. */
*ap++ = bp;
n = strlen(bp) + 1; /* for the \0 */
bp += n;
buflen -= n;
/* Get canonical name. */
n = strlen(tbuf) + 1; /* for the \0 */
if (n > buflen) {
had_error++;
continue;
}
strcpy(bp, tbuf);
host.h_name = bp;
bp += n;
buflen -= n;
continue;
}
if (qtype == T_PTR && type == T_CNAME) {
n = dn_expand(answer->buf, eom, cp, tbuf, sizeof tbuf);
#ifdef USE_RESOLV_NAME_OK
if ((n < 0) || !res_hnok(tbuf)) {
#else
if ((n < 0) || !_hokchar(tbuf)) {
#endif
had_error++;
continue;
}
cp += n;
/* Get canonical name. */
n = strlen(tbuf) + 1; /* for the \0 */
if (n > buflen) {
had_error++;
continue;
}
strcpy(bp, tbuf);
tname = bp;
bp += n;
buflen -= n;
continue;
}
if (type != qtype) {
syslog(LOG_NOTICE|LOG_AUTH,
"gethostby*.getanswer: asked for \"%s %s %s\", got type \"%s\"",
qname, p_class(C_IN), p_type(qtype),
p_type(type));
cp += n;
continue; /* XXX - had_error++ ? */
}
switch (type) {
case T_PTR:
if (strcasecmp(tname, bp) != 0) {
syslog(LOG_NOTICE|LOG_AUTH,
AskedForGot, qname, bp);
cp += n;
continue; /* XXX - had_error++ ? */
}
n = dn_expand(answer->buf, eom, cp, bp, buflen);
#ifdef USE_RESOLV_NAME_OK
if ((n < 0) || !res_hnok(bp)) {
#else
if ((n < 0) || !_hokchar(bp)) {
#endif
had_error++;
break;
}
#if MULTI_PTRS_ARE_ALIASES
cp += n;
if (!haveanswer)
host.h_name = bp;
else if (ap < &host_aliases[MAXALIASES-1])
*ap++ = bp;
else
n = -1;
if (n != -1) {
n = strlen(bp) + 1; /* for the \0 */
bp += n;
buflen -= n;
}
break;
#else
host.h_name = bp;
if (_res.options & RES_USE_INET6) {
n = strlen(bp) + 1; /* for the \0 */
bp += n;
buflen -= n;
map_v4v6_hostent(&host, &bp, &buflen);
}
h_errno = NETDB_SUCCESS;
return (&host);
#endif
case T_A:
case T_AAAA:
if (strcasecmp(host.h_name, bp) != 0) {
syslog(LOG_NOTICE|LOG_AUTH,
AskedForGot, host.h_name, bp);
cp += n;
continue; /* XXX - had_error++ ? */
}
if (n != host.h_length) {
cp += n;
continue;
}
if (!haveanswer) {
register int nn;
host.h_name = bp;
nn = strlen(bp) + 1; /* for the \0 */
bp += nn;
buflen -= nn;
}
bp += sizeof(align) - ((u_long)bp % sizeof(align));
if (bp + n >= &hostbuf[sizeof hostbuf]) {
#ifdef DEBUG
if (_res.options & RES_DEBUG)
printf("size (%d) too big\n", n);
#endif
had_error++;
continue;
}
if (hap >= &h_addr_ptrs[MAXADDRS-1]) {
if (!toobig++)
#ifdef DEBUG
if (_res.options & RES_DEBUG)
printf("Too many addresses (%d)\n", MAXADDRS);
#endif
cp += n;
continue;
}
bcopy(cp, *hap++ = bp, n);
bp += n;
buflen -= n;
cp += n;
break;
}
if (!had_error)
haveanswer++;
}
if (haveanswer) {
*ap = NULL;
*hap = NULL;
# if defined(RESOLVSORT)
/*
* Note: we sort even if host can take only one address
* in its return structures - should give it the "best"
* address in that case, not some random one
*/
if (_res.nsort && haveanswer > 1 && qtype == T_A)
addrsort(h_addr_ptrs, haveanswer);
# endif /*RESOLVSORT*/
if (!host.h_name) {
n = strlen(qname) + 1; /* for the \0 */
if (n > buflen)
goto try_again;
strcpy(bp, qname);
host.h_name = bp;
bp += n;
buflen -= n;
}
if (_res.options & RES_USE_INET6)
map_v4v6_hostent(&host, &bp, &buflen);
h_errno = NETDB_SUCCESS;
return (&host);
}
try_again:
h_errno = TRY_AGAIN;
return (NULL);
}
#ifdef notyet
/*
* XXX This is an extremely bogus implementation.
*
* FreeBSD has this interface:
* int gethostbyaddr_r(const char *addr, int len, int type,
* struct hostent *result, struct hostent_data *buffer)
*/
struct hostent *
gethostbyname_r(name, hp, buf, buflen, errorp)
const char * name;
struct hostent * hp;
char * buf;
int buflen;
int * errorp;
{
struct hostent *res;
res = gethostbyname(name);
*errorp = h_errno;
if (res == NULL)
return NULL;
memcpy(hp, res, sizeof *hp); /* XXX not sufficient */
return hp;
}
/*
* XXX This is an extremely bogus implementation.
*/
struct hostent *
gethostbyaddr_r(addr, len, af, he, buf, buflen, errorp)
const char *addr; /* XXX should have been def'd as u_char! */
int len, af;
struct hostent * he;
char * buf;
int buflen;
int * errorp;
{
struct hostent * res;
res = gethostbyaddr(addr, len, af);
*errorp = h_errno;
if (res == NULL)
return NULL;
memcpy(he, res, sizeof *he); /* XXX not sufficient */
return he;
}
/* XXX RFC2133 expects a gethostbyname2_r() -- unimplemented */
#endif
_THREAD_PRIVATE_MUTEX(gethostnamadr)
struct hostent *
gethostbyname(name)
const char *name;
{
struct hostent *hp;
extern struct hostent *_gethtbyname2();
_THREAD_PRIVATE_MUTEX_LOCK(gethostnamadr);
if ((_res.options & RES_INIT) == 0 && res_init() == -1)
hp = _gethtbyname2(name, AF_INET);
else if (_res.options & RES_USE_INET6) {
hp = gethostbyname2(name, AF_INET6);
if (hp == NULL)
hp = gethostbyname2(name, AF_INET);
}
else
hp = gethostbyname2(name, AF_INET);
_THREAD_PRIVATE_MUTEX_UNLOCK(gethostnamadr);
return hp;
}
struct hostent *
gethostbyname2(name, af)
const char *name;
int af;
{
querybuf buf;
register const char *cp;
char *bp;
int n, size, type, len, i;
extern struct hostent *_gethtbyname2(), *_yp_gethtbyname();
register struct hostent *hp;
char lookups[MAXDNSLUS];
if ((_res.options & RES_INIT) == 0 && res_init() == -1)
return (_gethtbyname2(name, af));
switch (af) {
case AF_INET:
size = INADDRSZ;
type = T_A;
break;
case AF_INET6:
size = IN6ADDRSZ;
type = T_AAAA;
break;
default:
h_errno = NETDB_INTERNAL;
errno = EAFNOSUPPORT;
return (NULL);
}
host.h_addrtype = af;
host.h_length = size;
/*
* if there aren't any dots, it could be a user-level alias.
* this is also done in res_query() since we are not the only
* function that looks up host names.
*/
if (!strchr(name, '.') && (cp = __hostalias(name)))
name = cp;
/*
* disallow names consisting only of digits/dots, unless
* they end in a dot.
*/
if (isdigit(name[0]))
for (cp = name;; ++cp) {
if (!*cp) {
if (*--cp == '.')
break;
/*
* All-numeric, no dot at the end.
* Fake up a hostent as if we'd actually
* done a lookup.
*/
if (inet_pton(af, name, host_addr) <= 0) {
h_errno = HOST_NOT_FOUND;
return (NULL);
}
strncpy(hostbuf, name, MAXHOSTNAMELEN-1);
hostbuf[MAXHOSTNAMELEN-1] = '\0';
bp = hostbuf + MAXHOSTNAMELEN;
len = sizeof hostbuf - MAXHOSTNAMELEN;
host.h_name = hostbuf;
host.h_aliases = host_aliases;
host_aliases[0] = NULL;
h_addr_ptrs[0] = (char *)host_addr;
h_addr_ptrs[1] = NULL;
host.h_addr_list = h_addr_ptrs;
if (_res.options & RES_USE_INET6)
map_v4v6_hostent(&host, &bp, &len);
h_errno = NETDB_SUCCESS;
return (&host);
}
if (!isdigit(*cp) && *cp != '.')
break;
}
if ((isxdigit(name[0]) && strchr(name, ':') != NULL) ||
name[0] == ':')
for (cp = name;; ++cp) {
if (!*cp) {
if (*--cp == '.')
break;
/*
* All-IPv6-legal, no dot at the end.
* Fake up a hostent as if we'd actually
* done a lookup.
*/
if (inet_pton(af, name, host_addr) <= 0) {
h_errno = HOST_NOT_FOUND;
return (NULL);
}
strncpy(hostbuf, name, MAXHOSTNAMELEN-1);
hostbuf[MAXHOSTNAMELEN-1] = '\0';
bp = hostbuf + MAXHOSTNAMELEN;
len = sizeof hostbuf - MAXHOSTNAMELEN;
host.h_name = hostbuf;
host.h_aliases = host_aliases;
host_aliases[0] = NULL;
h_addr_ptrs[0] = (char *)host_addr;
h_addr_ptrs[1] = NULL;
host.h_addr_list = h_addr_ptrs;
h_errno = NETDB_SUCCESS;
return (&host);
}
if (!isxdigit(*cp) && *cp != ':' && *cp != '.')
break;
}
bcopy(_res.lookups, lookups, sizeof lookups);
if (lookups[0] == '\0')
strncpy(lookups, "bf", sizeof lookups);
hp = (struct hostent *)NULL;
for (i = 0; i < MAXDNSLUS && hp == NULL && lookups[i]; i++) {
switch (lookups[i]) {
#ifdef YP
case 'y':
/* YP only supports AF_INET. */
if (af == AF_INET)
hp = _yp_gethtbyname(name);
break;
#endif
case 'b':
if ((n = res_search(name, C_IN, type, buf.buf,
sizeof(buf))) < 0) {
#ifdef DEBUG
if (_res.options & RES_DEBUG)
printf("res_search failed\n");
#endif
break;
}
hp = getanswer(&buf, n, name, type);
break;
case 'f':
hp = _gethtbyname2(name, af);
break;
}
}
/* XXX h_errno not correct in all cases... */
return (hp);
}
struct hostent *
gethostbyaddr(addr, len, af)
const char *addr; /* XXX should have been def'd as u_char! */
int len, af;
{
const u_char *uaddr = (const u_char *)addr;
int n, size, i;
querybuf buf;
register struct hostent *hp;
char qbuf[MAXDNAME+1], *qp;
extern struct hostent *_gethtbyaddr(), *_yp_gethtbyaddr();
char lookups[MAXDNSLUS];
struct hostent *res;
_THREAD_PRIVATE_MUTEX_LOCK(gethostnamadr);
if ((_res.options & RES_INIT) == 0 && res_init() == -1) {
res = _gethtbyaddr(addr, len, af);
_THREAD_PRIVATE_MUTEX_UNLOCK(gethostnamadr);
return (res);
}
if (af == AF_INET6 && len == IN6ADDRSZ &&
(IN6_IS_ADDR_V4MAPPED((struct in6_addr *)uaddr) ||
IN6_IS_ADDR_V4COMPAT((struct in6_addr *)uaddr))) {
/* Unmap. */
addr += IN6ADDRSZ - INADDRSZ;
uaddr += IN6ADDRSZ - INADDRSZ;
af = AF_INET;
len = INADDRSZ;
}
switch (af) {
case AF_INET:
size = INADDRSZ;
break;
case AF_INET6:
size = IN6ADDRSZ;
break;
default:
errno = EAFNOSUPPORT;
h_errno = NETDB_INTERNAL;
_THREAD_PRIVATE_MUTEX_UNLOCK(gethostnamadr);
return (NULL);
}
if (size != len) {
errno = EINVAL;
h_errno = NETDB_INTERNAL;
_THREAD_PRIVATE_MUTEX_UNLOCK(gethostnamadr);
return (NULL);
}
switch (af) {
case AF_INET:
(void) sprintf(qbuf, "%u.%u.%u.%u.in-addr.arpa",
(uaddr[3] & 0xff),
(uaddr[2] & 0xff),
(uaddr[1] & 0xff),
(uaddr[0] & 0xff));
break;
case AF_INET6:
qp = qbuf;
for (n = IN6ADDRSZ - 1; n >= 0; n--) {
qp += sprintf(qp, "%x.%x.",
uaddr[n] & 0xf,
(uaddr[n] >> 4) & 0xf);
}
strcpy(qp, "ip6.int");
break;
}
bcopy(_res.lookups, lookups, sizeof lookups);
if (lookups[0] == '\0')
strncpy(lookups, "bf", sizeof lookups);
hp = (struct hostent *)NULL;
for (i = 0; i < MAXDNSLUS && hp == NULL && lookups[i]; i++) {
switch (lookups[i]) {
#ifdef YP
case 'y':
/* YP only supports AF_INET. */
if (af == AF_INET)
hp = _yp_gethtbyaddr(addr);
break;
#endif
case 'b':
n = res_query(qbuf, C_IN, T_PTR, (u_char *)buf.buf,
sizeof buf.buf);
if (n < 0) {
#ifdef DEBUG
if (_res.options & RES_DEBUG)
printf("res_query failed\n");
#endif
break;
}
if (!(hp = getanswer(&buf, n, qbuf, T_PTR)))
break;
hp->h_addrtype = af;
hp->h_length = len;
bcopy(addr, host_addr, len);
h_addr_ptrs[0] = (char *)host_addr;
h_addr_ptrs[1] = NULL;
if (af == AF_INET && (_res.options & RES_USE_INET6)) {
map_v4v6_address((char*)host_addr,
(char*)host_addr);
hp->h_addrtype = AF_INET6;
hp->h_length = IN6ADDRSZ;
}
h_errno = NETDB_SUCCESS;
break;
case 'f':
hp = _gethtbyaddr(addr, len, af);
break;
}
}
_THREAD_PRIVATE_MUTEX_UNLOCK(gethostnamadr);
/* XXX h_errno not correct in all cases... */
return (hp);
}
void
_sethtent(f)
int f;
{
if (hostf == NULL)
hostf = fopen(_PATH_HOSTS, "r" );
else
rewind(hostf);
stayopen = f;
}
void
_endhtent()
{
if (hostf && !stayopen) {
(void) fclose(hostf);
hostf = NULL;
}
}
struct hostent *
_gethtent()
{
char *p;
register char *cp, **q;
int af;
size_t len;
if (!hostf && !(hostf = fopen(_PATH_HOSTS, "r" ))) {
h_errno = NETDB_INTERNAL;
return (NULL);
}
again:
if ((p = fgetln(hostf, &len)) == NULL) {
h_errno = HOST_NOT_FOUND;
return (NULL);
}
if (p[len-1] == '\n')
len--;
if (len >= sizeof(hostbuf) || len == 0)
goto again;
p = memcpy(hostbuf, p, len);
hostbuf[len] = '\0';
if (*p == '#')
goto again;
if ((cp = strchr(p, '#')))
*cp = '\0';
if (!(cp = strpbrk(p, " \t")))
goto again;
*cp++ = '\0';
if ((_res.options & RES_USE_INET6) &&
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;
}
/* if this is not something we're looking for, skip it. */
if (host.h_addrtype != af)
goto again;
if (host.h_length != len)
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")))
*cp++ = '\0';
while (cp && *cp) {
if (*cp == ' ' || *cp == '\t') {
cp++;
continue;
}
if (q < &host_aliases[MAXALIASES - 1])
*q++ = cp;
if ((cp = strpbrk(cp, " \t")))
*cp++ = '\0';
}
*q = NULL;
if (_res.options & RES_USE_INET6) {
char *bp = hostbuf;
int buflen = sizeof hostbuf;
map_v4v6_hostent(&host, &bp, &buflen);
}
h_errno = NETDB_SUCCESS;
return (&host);
}
struct hostent *
_gethtbyname(name)
const char *name;
{
extern struct hostent *_gethtbyname2();
struct hostent *hp;
if (_res.options & RES_USE_INET6) {
hp = _gethtbyname2(name, AF_INET6);
if (hp)
return (hp);
}
return (_gethtbyname2(name, AF_INET));
}
struct hostent *
_gethtbyname2(name, af)
const char *name;
int af;
{
register struct hostent *p;
register char **cp;
_sethtent(0);
while ((p = _gethtent())) {
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:
_endhtent();
return (p);
}
struct hostent *
_gethtbyaddr(addr, len, af)
const char *addr;
int len, af;
{
register struct hostent *p;
host.h_length = len;
host.h_addrtype = af;
_sethtent(0);
while ((p = _gethtent()))
if (p->h_addrtype == af && !bcmp(p->h_addr, addr, len))
break;
_endhtent();
return (p);
}
#ifdef YP
struct hostent *
_yphostent(line)
char *line;
{
static struct in_addr host_addrs[MAXADDRS];
char *p = line;
char *cp, **q;
char **hap;
struct in_addr *buf;
int more;
host.h_name = NULL;
host.h_addr_list = h_addr_ptrs;
host.h_length = INADDRSZ;
host.h_addrtype = AF_INET;
hap = h_addr_ptrs;
buf = host_addrs;
q = host.h_aliases = host_aliases;
nextline:
more = 0;
cp = strpbrk(p, " \t");
if (cp == NULL) {
if (host.h_name == NULL)
return (NULL);
else
goto done;
}
*cp++ = '\0';
*hap++ = (char *)buf;
(void) inet_aton(p, buf++);
while (*cp == ' ' || *cp == '\t')
cp++;
p = cp;
cp = strpbrk(p, " \t\n");
if (cp != NULL) {
if (*cp == '\n')
more = 1;
*cp++ = '\0';
}
if (!host.h_name)
host.h_name = p;
else if (strcmp(host.h_name, p)==0)
;
else if (q < &host_aliases[MAXALIASES - 1])
*q++ = p;
p = cp;
if (more)
goto nextline;
while (cp && *cp) {
if (*cp == ' ' || *cp == '\t') {
cp++;
continue;
}
if (*cp == '\n') {
cp++;
goto nextline;
}
if (q < &host_aliases[MAXALIASES - 1])
*q++ = cp;
cp = strpbrk(cp, " \t");
if (cp != NULL)
*cp++ = '\0';
}
done:
*q = NULL;
*hap = NULL;
return (&host);
}
struct hostent *
_yp_gethtbyaddr(addr)
const char *addr;
{
struct hostent *hp = (struct hostent *)NULL;
static char *__ypcurrent;
int __ypcurrentlen, r;
char name[sizeof("xxx.xxx.xxx.xxx")];
if (!__ypdomain) {
if (_yp_check(&__ypdomain) == 0)
return (hp);
}
sprintf(name, "%u.%u.%u.%u",
((unsigned)addr[0] & 0xff),
((unsigned)addr[1] & 0xff),
((unsigned)addr[2] & 0xff),
((unsigned)addr[3] & 0xff));
if (__ypcurrent)
free(__ypcurrent);
__ypcurrent = NULL;
r = yp_match(__ypdomain, "hosts.byaddr", name,
strlen(name), &__ypcurrent, &__ypcurrentlen);
if (r==0)
hp = _yphostent(__ypcurrent);
if (hp==NULL)
h_errno = HOST_NOT_FOUND;
return (hp);
}
struct hostent *
_yp_gethtbyname(name)
const char *name;
{
struct hostent *hp = (struct hostent *)NULL;
static char *__ypcurrent;
int __ypcurrentlen, r;
if (strlen(name) >= MAXHOSTNAMELEN)
return (NULL);
if (!__ypdomain) {
if (_yp_check(&__ypdomain) == 0)
return (hp);
}
if (__ypcurrent)
free(__ypcurrent);
__ypcurrent = NULL;
r = yp_match(__ypdomain, "hosts.byname", name,
strlen(name), &__ypcurrent, &__ypcurrentlen);
if (r == 0)
hp = _yphostent(__ypcurrent);
if (hp == NULL)
h_errno = HOST_NOT_FOUND;
return (hp);
}
#endif
static void
map_v4v6_address(src, dst)
const char *src;
char *dst;
{
u_char *p = (u_char *)dst;
char tmp[INADDRSZ];
int i;
/* Stash a temporary copy so our caller can update in place. */
bcopy(src, tmp, INADDRSZ);
/* Mark this ipv6 addr as a mapped ipv4. */
for (i = 0; i < 10; i++)
*p++ = 0x00;
*p++ = 0xff;
*p++ = 0xff;
/* Retrieve the saved copy and we're done. */
bcopy(tmp, (void*)p, INADDRSZ);
}
static void
map_v4v6_hostent(hp, bpp, lenp)
struct hostent *hp;
char **bpp;
int *lenp;
{
char **ap;
if (hp->h_addrtype != AF_INET || hp->h_length != INADDRSZ)
return;
hp->h_addrtype = AF_INET6;
hp->h_length = IN6ADDRSZ;
for (ap = hp->h_addr_list; *ap; ap++) {
int i = sizeof(align) - ((u_long)*bpp % sizeof(align));
if (*lenp < (i + IN6ADDRSZ)) {
/* Out of memory. Truncate address list here. XXX */
*ap = NULL;
return;
}
*bpp += i;
*lenp -= i;
map_v4v6_address(*ap, *bpp);
*ap = *bpp;
*bpp += IN6ADDRSZ;
*lenp -= IN6ADDRSZ;
}
}
struct hostent *
gethostent()
{
return (_gethtent());
}
#ifdef RESOLVSORT
static void
addrsort(ap, num)
char **ap;
int num;
{
int i, j;
char **p;
short aval[MAXADDRS];
int needsort = 0;
p = ap;
for (i = 0; i < num; i++, p++) {
for (j = 0 ; (unsigned)j < _res.nsort; j++)
if (_res.sort_list[j].addr.s_addr ==
(((struct in_addr *)(*p))->s_addr & _res.sort_list[j].mask))
break;
aval[i] = j;
if (needsort == 0 && i > 0 && j < aval[i-1])
needsort = i;
}
if (!needsort)
return;
while (needsort < num) {
for (j = needsort - 1; j >= 0; j--) {
if (aval[j] > aval[j+1]) {
char *hp;
i = aval[j];
aval[j] = aval[j+1];
aval[j+1] = i;
hp = ap[j];
ap[j] = ap[j+1];
ap[j+1] = hp;
} else
break;
}
needsort++;
}
}
#endif
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