* Copyright (c) 1985, 1988 Regents of the University of California.
* Redistribution and use in source and binary forms are permitted
* provided that the above copyright notice and this paragraph are
* duplicated in all such forms and that any documentation,
* advertising materials, and other materials related to such
* distribution and use acknowledge that the software was developed
* by the University of California, Berkeley. The name of the
* University may not be used to endorse or promote products derived
* from this software without specific prior written permission.
* THIS SOFTWARE IS PROVIDED ``AS IS'' AND WITHOUT ANY EXPRESS OR
* IMPLIED WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED
* WARRANTIES OF MERCHANTIBILITY AND FITNESS FOR A PARTICULAR PURPOSE.
#if defined(LIBC_SCCS) && !defined(lint)
static char sccsid
[] = "@(#)gethostnamadr.c 6.36 (Berkeley) 10/7/88";
#endif /* LIBC_SCCS and not lint */
#include <arpa/nameser.h>
static char *h_addr_ptrs
[MAXADDRS
+ 1];
static struct hostent host
;
static char *host_aliases
[MAXALIASES
];
static char hostbuf
[BUFSIZ
+1];
static struct in_addr host_addr
;
static char HOSTDB
[] = "/etc/hosts";
static FILE *hostf
= NULL
;
static char hostaddr
[MAXADDRS
];
static char *host_addrs
[2];
#define MAXPACKET PACKETSZ
getanswer(answer
, anslen
, iquery
)
int type
, class, buflen
, ancount
, qdcount
;
int haveanswer
, getclass
= C_ANY
;
eom
= answer
->buf
+ anslen
;
* find first satisfactory answer
ancount
= ntohs(hp
->ancount
);
qdcount
= ntohs(hp
->qdcount
);
buflen
= sizeof(hostbuf
);
cp
= answer
->buf
+ sizeof(HEADER
);
if ((n
= dn_expand((char *)answer
->buf
, eom
,
return ((struct hostent
*) NULL
);
cp
+= dn_skipname(cp
, eom
) + QFIXEDSZ
;
cp
+= dn_skipname(cp
, eom
) + QFIXEDSZ
;
h_errno
= HOST_NOT_FOUND
;
return ((struct hostent
*) NULL
);
host
.h_aliases
= host_aliases
;
#if BSD >= 43 || defined(h_addr) /* new-style hostent structure */
host
.h_addr_list
= h_addr_ptrs
;
while (--ancount
>= 0 && cp
< eom
) {
if ((n
= dn_expand((char *)answer
->buf
, eom
, cp
, bp
, buflen
)) < 0)
cp
+= sizeof(u_short
) + sizeof(u_long
);
if (ap
>= &host_aliases
[MAXALIASES
-1])
if (iquery
&& type
== T_PTR
) {
if ((n
= dn_expand((char *)answer
->buf
, eom
,
if (iquery
|| type
!= T_A
) {
if (_res
.options
& RES_DEBUG
)
printf("unexpected answer type %d, size %d\n",
if (n
!= host
.h_length
) {
host
.h_addrtype
= (class == C_IN
) ? AF_INET
: AF_UNSPEC
;
bp
+= sizeof(align
) - ((u_long
)bp
% sizeof(align
));
if (bp
+ n
>= &hostbuf
[sizeof(hostbuf
)]) {
if (_res
.options
& RES_DEBUG
)
printf("size (%d) too big\n", n
);
bcopy(cp
, *hap
++ = bp
, n
);
#if BSD >= 43 || defined(h_addr) /* new-style hostent structure */
host
.h_addr
= h_addr_ptrs
[0];
return ((struct hostent
*) NULL
);
extern struct hostent
*_gethtbyname();
* disallow names consisting only of digits/dots, unless
h_errno
= HOST_NOT_FOUND
;
return ((struct hostent
*) NULL
);
if (!isdigit(*cp
) && *cp
!= '.')
if ((n
= res_search(name
, C_IN
, T_A
, buf
.buf
, sizeof(buf
))) < 0) {
if (_res
.options
& RES_DEBUG
)
printf("res_search failed\n");
if (errno
== ECONNREFUSED
)
return (_gethtbyname(name
));
return ((struct hostent
*) NULL
);
return (getanswer(&buf
, n
, 0));
gethostbyaddr(addr
, len
, type
)
register struct hostent
*hp
;
extern struct hostent
*_gethtbyaddr();
return ((struct hostent
*) NULL
);
(void)sprintf(qbuf
, "%u.%u.%u.%u.in-addr.arpa",
((unsigned)addr
[3] & 0xff),
((unsigned)addr
[2] & 0xff),
((unsigned)addr
[1] & 0xff),
((unsigned)addr
[0] & 0xff));
n
= res_query(qbuf
, C_IN
, T_PTR
, (char *)&buf
, sizeof(buf
));
if (_res
.options
& RES_DEBUG
)
printf("res_query failed\n");
if (errno
== ECONNREFUSED
)
return (_gethtbyaddr(addr
, len
, type
));
return ((struct hostent
*) NULL
);
hp
= getanswer(&buf
, n
, 1);
return ((struct hostent
*) NULL
);
h_addr_ptrs
[0] = (char *)&host_addr
;
h_addr_ptrs
[1] = (char *)0;
host_addr
= *(struct in_addr
*)addr
;
hostf
= fopen(HOSTDB
, "r" );
if (hostf
&& !stayopen
) {
if (hostf
== NULL
&& (hostf
= fopen(HOSTDB
, "r" )) == NULL
)
if ((p
= fgets(hostbuf
, BUFSIZ
, hostf
)) == NULL
)
/* THIS STUFF IS INTERNET SPECIFIC */
#if BSD >= 43 || defined(h_addr) /* new-style hostent structure */
host
.h_addr_list
= host_addrs
;
*((u_long
*)host
.h_addr
) = inet_addr(p
);
host
.h_length
= sizeof (u_long
);
host
.h_addrtype
= AF_INET
;
while (*cp
== ' ' || *cp
== '\t')
q
= host
.h_aliases
= host_aliases
;
if (*cp
== ' ' || *cp
== '\t') {
if (q
< &host_aliases
[MAXALIASES
- 1])
for (mp
= match
; *mp
; mp
++)
register struct hostent
*p
;
while (p
= _gethtent()) {
if (strcasecmp(p
->h_name
, name
) == 0)
for (cp
= p
->h_aliases
; *cp
!= 0; cp
++)
if (strcasecmp(*cp
, name
) == 0)
_gethtbyaddr(addr
, len
, type
)
register struct hostent
*p
;
if (p
->h_addrtype
== type
&& !bcmp(p
->h_addr
, addr
, len
))