[thirdparty/glibc.git] / resolv / nss_dns / dns-network.c

/* Copyright (C) 1996, 1997, 1998, 1999 Free Software Foundation, Inc.
   This file is part of the GNU C Library.
   Extended from original form by Ulrich Drepper <drepper@cygnus.com>, 1996.

   The GNU C Library is free software; you can redistribute it and/or
   modify it under the terms of the GNU Library General Public License as
   published by the Free Software Foundation; either version 2 of the
   License, or (at your option) any later version.

   The GNU C Library is distributed in the hope that it will be useful,
   but WITHOUT ANY WARRANTY; without even the implied warranty of
   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
   Library General Public License for more details.

   You should have received a copy of the GNU Library General Public
   License along with the GNU C Library; see the file COPYING.LIB.  If not,
   write to the Free Software Foundation, Inc., 59 Temple Place - Suite 330,
   Boston, MA 02111-1307, USA.  */

/* Parts of this file are plain copies of the file `getnetnamadr.c' from
   the bind package and it has the following copyright.  */

/* Copyright (c) 1993 Carlos Leandro and Rui Salgueiro
 *      Dep. Matematica Universidade de Coimbra, Portugal, Europe
 *
 * 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.
 */
/*
 * Copyright (c) 1983, 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.
 * 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.
 */

#include <ctype.h>
#include <errno.h>
#include <netdb.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>

#include "nsswitch.h"
#include <arpa/inet.h>

/* Maximum number of aliases we allow.  */
#define MAX_NR_ALIASES	48


#if PACKETSZ > 1024
#define MAXPACKET       PACKETSZ
#else
#define MAXPACKET       1024
#endif


typedef enum
{
  BYADDR,
  BYNAME
} lookup_method;


/* We need this time later.  */
typedef union querybuf
{
  HEADER hdr;
  u_char buf[MAXPACKET];
} querybuf;

/* These functions are defined in res_comp.c.  */
#define NS_MAXCDNAME	255	/* maximum compressed domain name */
extern int __ns_name_ntop __P ((const u_char *, char *, size_t));
extern int __ns_name_unpack __P ((const u_char *, const u_char *,
				  const u_char *, u_char *, size_t));


/* Prototypes for local functions.  */
static enum nss_status getanswer_r (const querybuf *answer, int anslen,
				    struct netent *result, char *buffer,
				    size_t buflen, lookup_method net_i);


enum nss_status
_nss_dns_getnetbyname_r (const char *name, struct netent *result,
			 char *buffer, size_t buflen, int *errnop)
{
  /* Return entry for network with NAME.  */
  querybuf net_buffer;
  int anslen;
  char *qbuf;

  qbuf = strdupa (name);
  anslen = res_search (qbuf, C_IN, T_PTR, (u_char *) &net_buffer,
		       sizeof (querybuf));
  if (anslen < 0)
    {
      /* Nothing found.  */
      *errnop = errno;
      return (errno == ECONNREFUSED
	      || errno == EPFNOSUPPORT
	      || errno == EAFNOSUPPORT)
	? NSS_STATUS_UNAVAIL : NSS_STATUS_NOTFOUND;
    }

  return getanswer_r (&net_buffer, anslen, result, buffer, buflen, BYNAME);
}


enum nss_status
_nss_dns_getnetbyaddr_r (long net, int type, struct netent *result,
			 char *buffer, size_t buflen, int *errnop)
{
  /* Return entry for network with NAME.  */
  enum nss_status status;
  querybuf net_buffer;
  unsigned int net_bytes[4];
  char qbuf[MAXDNAME];
  int cnt, anslen;
  u_int32_t net2;

  /* No net address lookup for IPv6 yet.  */
  if (type != AF_INET)
    return NSS_STATUS_UNAVAIL;

  net2 = (u_int32_t) net;
  for (cnt = 4; net2 != 0; net2 >>= 8)
    net_bytes[--cnt] = net2 & 0xff;

  switch (cnt)
    {
    case 3:
      /* Class A network.  */
      sprintf (qbuf, "0.0.0.%u.in-addr.arpa", net_bytes[3]);
      break;
    case 2:
      /* Class B network.  */
      sprintf (qbuf, "0.0.%u.%u.in-addr.arpa", net_bytes[3], net_bytes[2]);
      break;
    case 1:
      /* Class C network.  */
      sprintf (qbuf, "0.%u.%u.%u.in-addr.arpa", net_bytes[3], net_bytes[2],
	       net_bytes[1]);
      break;
    case 0:
      /* Class D - E network.  */
      sprintf (qbuf, "%u.%u.%u.%u.in-addr.arpa", net_bytes[3], net_bytes[2],
	       net_bytes[1], net_bytes[0]);
      break;
    }

  anslen = res_query (qbuf, C_IN, T_PTR, (u_char *) &net_buffer,
		      sizeof (querybuf));
  if (anslen < 0)
    {
      /* Nothing found.  */
      *errnop = errno;
      return (errno == ECONNREFUSED
	      || errno == EPFNOSUPPORT
	      || errno == EAFNOSUPPORT)
	? NSS_STATUS_UNAVAIL : NSS_STATUS_NOTFOUND;
    }

  status = getanswer_r (&net_buffer, anslen, result, buffer, buflen, BYADDR);
  if (status == NSS_STATUS_SUCCESS)
    {
      /* Strip trailing zeros.  */
      unsigned int u_net = net;	/* Maybe net should be unsigned?  */

      while ((u_net & 0xff) == 0 && u_net != 0)
	u_net >>= 8;
      result->n_net = u_net;
    }

  return status;
}


#undef offsetof
#define offsetof(Type, Member) ((size_t) &((Type *) NULL)->Member)

static enum nss_status
getanswer_r (const querybuf *answer, int anslen, struct netent *result,
	     char *buffer, size_t buflen, lookup_method net_i)
{
  /*
   * Find first satisfactory answer
   *
   *      answer --> +------------+  ( MESSAGE )
   *                 |   Header   |
   *                 +------------+
   *                 |  Question  | the question for the name server
   *                 +------------+
   *                 |   Answer   | RRs answering the question
   *                 +------------+
   *                 | Authority  | RRs pointing toward an authority
   *                 | Additional | RRs holding additional information
   *                 +------------+
   */
  struct net_data
  {
    char *aliases[MAX_NR_ALIASES];
    char linebuffer[0];
  } *net_data = (struct net_data *) buffer;
  int linebuflen = buflen - offsetof (struct net_data, linebuffer);
  const char *end_of_message = &answer->buf[anslen];
  const HEADER *header_pointer = &answer->hdr;
  /* #/records in the answer section.  */
  int answer_count =  ntohs (header_pointer->ancount);
  /* #/entries in the question section.  */
  int question_count = ntohs (header_pointer->qdcount);
  char *bp = net_data->linebuffer;
  const char *cp = &answer->buf[HFIXEDSZ];
  char **alias_pointer;
  int have_answer;
  char *ans;
  u_char packtmp[NS_MAXCDNAME];

  if (question_count == 0)
    {
      /* FIXME: the Sun version uses for host name lookup an additional
	 parameter for pointing to h_errno.  this is missing here.
	 OSF/1 has a per-thread h_errno variable.  */
      if (header_pointer->aa != 0)
	{
	  __set_h_errno (HOST_NOT_FOUND);
	  return NSS_STATUS_NOTFOUND;
	}
      else
	{
	  __set_h_errno (TRY_AGAIN);
	  return NSS_STATUS_TRYAGAIN;
	}
    }

  /* Skip the question part.  */
  while (question_count-- > 0)
    cp += __dn_skipname (cp, end_of_message) + QFIXEDSZ;

  alias_pointer = result->n_aliases = &net_data->aliases[0];
  *alias_pointer = NULL;
  have_answer = 0;
  ans = NULL;

  while (--answer_count >= 0 && cp < end_of_message)
    {
      int n = dn_expand (answer->buf, end_of_message, cp, bp, linebuflen);
      int type, class;

      n = __ns_name_unpack (answer->buf, end_of_message, cp,
			    packtmp, sizeof packtmp);
      if (n != -1 && __ns_name_ntop (packtmp, bp, linebuflen) == -1)
	{
	  if (errno == EMSGSIZE)
	    {
	      errno = ERANGE;
	      return NSS_STATUS_TRYAGAIN;
	    }

	  n = -1;
	}

      if (n > 0 && bp[0] == '.')
	bp[0] = '\0';

      if (n < 0 || res_dnok (bp) == 0)
	break;
      cp += n;
      ans = strdupa (bp);
      GETSHORT (type, cp);
      GETSHORT (class, cp);
      cp += INT32SZ;		/* TTL */
      GETSHORT (n, cp);

      if (class == C_IN && type == T_PTR)
	{
	  n = __ns_name_unpack (answer->buf, end_of_message, cp,
				packtmp, sizeof packtmp);
	  if (n != -1 && __ns_name_ntop (packtmp, bp, linebuflen) == -1)
	    {
	      if (errno == EMSGSIZE)
		{
		  errno = ERANGE;
		  return NSS_STATUS_TRYAGAIN;
		}

	      n = -1;
	    }

	  if (n < 0 || !res_hnok (bp))
	    {
	      /* XXX What does this mean?  The original form from bind
		 returns NULL. Incrementing cp has no effect in any case.
		 What should I return here. ??? */
	      cp += n;
	      return NSS_STATUS_UNAVAIL;
	    }
	  cp += n;
	  *alias_pointer++ = bp;
	  bp += strlen (bp) + 1;
	  result->n_addrtype = class == C_IN ? AF_INET : AF_UNSPEC;
	  ++have_answer;
	}
    }

  if (have_answer)
    {
      char *tmp;
      int len;
      char *in, *cp, *rp, *wp;
      int cnt, first_flag;

      *alias_pointer = NULL;
      switch (net_i)
	{
	case BYADDR:
	  result->n_name = result->n_aliases[0];
	  result->n_net = 0L;
	  break;
	case BYNAME:
	  len = strlen (result->n_aliases[0]);
	  tmp = (char *) alloca (len + 1);
	  tmp[len] = 0;
	  wp = &tmp[len - 1];

	  rp = in = result->n_aliases[0];
	  result->n_name = ans;

	  first_flag = 1;
	  for (cnt = 0; cnt < 4; ++cnt)
	    {
	      char *startp;

	      startp = rp;
	      while (*rp != '.')
		++rp;
	      if (rp - startp > 1 || *startp != '0' || !first_flag)
		{
		  first_flag = 0;
		  if (cnt > 0)
		    *wp-- = '.';
		  cp = rp;
		  while (cp > startp)
		    *wp-- = *--cp;
		}
	      in = rp + 1;
	    }

	  result->n_net = inet_network (wp);
	  break;
	}

      ++result->n_aliases;
      return NSS_STATUS_SUCCESS;
    }

  __set_h_errno (TRY_AGAIN);
  return NSS_STATUS_TRYAGAIN;
}
Commit	Line	Data
8d8c6efa	1	/* Copyright (C) 1996, 1997, 1998, 1999 Free Software Foundation, Inc.
84384f5b UD	2	This file is part of the GNU C Library.
84384f5b UD	3	Extended from original form by Ulrich Drepper <drepper@cygnus.com>, 1996.
5f0e6fc7	4
84384f5b UD	5	The GNU C Library is free software; you can redistribute it and/or
	6	modify it under the terms of the GNU Library General Public License as
	7	published by the Free Software Foundation; either version 2 of the
	8	License, or (at your option) any later version.
5f0e6fc7	9
84384f5b UD	10	The GNU C Library is distributed in the hope that it will be useful,
	11	but WITHOUT ANY WARRANTY; without even the implied warranty of
	12	MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
	13	Library General Public License for more details.
5f0e6fc7	14
84384f5b UD	15	You should have received a copy of the GNU Library General Public
	16	License along with the GNU C Library; see the file COPYING.LIB. If not,
	17	write to the Free Software Foundation, Inc., 59 Temple Place - Suite 330,
	18	Boston, MA 02111-1307, USA. */
5f0e6fc7 RM	19
	20	/* Parts of this file are plain copies of the file `getnetnamadr.c' from
	21	the bind package and it has the following copyright. */
	22
	23	/* Copyright (c) 1993 Carlos Leandro and Rui Salgueiro
	24	* Dep. Matematica Universidade de Coimbra, Portugal, Europe
	25	*
	26	* Permission to use, copy, modify, and distribute this software for any
	27	* purpose with or without fee is hereby granted, provided that the above
	28	* copyright notice and this permission notice appear in all copies.
	29	*/
	30	/*
	31	* Copyright (c) 1983, 1993
	32	* The Regents of the University of California. All rights reserved.
	33	*
	34	* Redistribution and use in source and binary forms, with or without
	35	* modification, are permitted provided that the following conditions
	36	* are met:
	37	* 1. Redistributions of source code must retain the above copyright
	38	* notice, this list of conditions and the following disclaimer.
	39	* 2. Redistributions in binary form must reproduce the above copyright
	40	* notice, this list of conditions and the following disclaimer in the
	41	* documentation and/or other materials provided with the distribution.
5f0e6fc7 RM	42	* 4. Neither the name of the University nor the names of its contributors
	43	* may be used to endorse or promote products derived from this software
	44	* without specific prior written permission.
	45	*
	46	* THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
	47	* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
	48	* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
	49	* ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
	50	* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
	51	* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
	52	* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
	53	* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
	54	* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
	55	* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
	56	* SUCH DAMAGE.
	57	*/
	58
	59	#include <ctype.h>
	60	#include <errno.h>
	61	#include <netdb.h>
	62	#include <stdio.h>
	63	#include <stdlib.h>
	64	#include <string.h>
	65
	66	#include "nsswitch.h"
	67	#include <arpa/inet.h>
	68
	69	/* Maximum number of aliases we allow. */
	70	#define MAX_NR_ALIASES 48
	71
	72
	73	#if PACKETSZ > 1024
	74	#define MAXPACKET PACKETSZ
	75	#else
	76	#define MAXPACKET 1024
	77	#endif
	78
	79
	80	typedef enum
	81	{
	82	BYADDR,
	83	BYNAME
	84	} lookup_method;
	85
	86
	87	/* We need this time later. */
	88	typedef union querybuf
	89	{
	90	HEADER hdr;
	91	u_char buf[MAXPACKET];
	92	} querybuf;
	93
8d8c6efa UD	94	/* These functions are defined in res_comp.c. */
	95	#define NS_MAXCDNAME 255 /* maximum compressed domain name */
	96	extern int __ns_name_ntop __P ((const u_char , char , size_t));
	97	extern int __ns_name_unpack __P ((const u_char , const u_char ,
	98	const u_char , u_char , size_t));
	99
5f0e6fc7	100
6d52618b	101	/* Prototypes for local functions. */
84384f5b UD	102	static enum nss_status getanswer_r (const querybuf *answer, int anslen,
84384f5b UD	103	struct netent result, char buffer,
df4ef2ab	104	size_t buflen, lookup_method net_i);
5f0e6fc7 RM	105
5f0e6fc7 RM	106
84384f5b	107	enum nss_status
5f0e6fc7	108	_nss_dns_getnetbyname_r (const char name, struct netent result,
67479a70	109	char buffer, size_t buflen, int errnop)
5f0e6fc7 RM	110	{
	111	/* Return entry for network with NAME. */
	112	querybuf net_buffer;
	113	int anslen;
	114	char *qbuf;
	115
	116	qbuf = strdupa (name);
	117	anslen = res_search (qbuf, C_IN, T_PTR, (u_char *) &net_buffer,
	118	sizeof (querybuf));
	119	if (anslen < 0)
67479a70 UD	120	{
	121	/* Nothing found. */
	122	*errnop = errno;
	123	return (errno == ECONNREFUSED
	124	\|\| errno == EPFNOSUPPORT
	125	\|\| errno == EAFNOSUPPORT)
	126	? NSS_STATUS_UNAVAIL : NSS_STATUS_NOTFOUND;
	127	}
5f0e6fc7 RM	128
	129	return getanswer_r (&net_buffer, anslen, result, buffer, buflen, BYNAME);
	130	}
	131
	132
84384f5b	133	enum nss_status
5f0e6fc7	134	_nss_dns_getnetbyaddr_r (long net, int type, struct netent *result,
67479a70	135	char buffer, size_t buflen, int errnop)
5f0e6fc7 RM	136	{
5f0e6fc7 RM	137	/* Return entry for network with NAME. */
84384f5b	138	enum nss_status status;
5f0e6fc7 RM	139	querybuf net_buffer;
	140	unsigned int net_bytes[4];
	141	char qbuf[MAXDNAME];
	142	int cnt, anslen;
	143	u_int32_t net2;
	144
	145	/* No net address lookup for IPv6 yet. */
	146	if (type != AF_INET)
	147	return NSS_STATUS_UNAVAIL;
	148
	149	net2 = (u_int32_t) net;
	150	for (cnt = 4; net2 != 0; net2 >>= 8)
	151	net_bytes[--cnt] = net2 & 0xff;
	152
	153	switch (cnt)
	154	{
	155	case 3:
	156	/* Class A network. */
	157	sprintf (qbuf, "0.0.0.%u.in-addr.arpa", net_bytes[3]);
	158	break;
	159	case 2:
	160	/* Class B network. */
	161	sprintf (qbuf, "0.0.%u.%u.in-addr.arpa", net_bytes[3], net_bytes[2]);
	162	break;
	163	case 1:
	164	/* Class C network. */
	165	sprintf (qbuf, "0.%u.%u.%u.in-addr.arpa", net_bytes[3], net_bytes[2],
	166	net_bytes[1]);
	167	break;
	168	case 0:
	169	/* Class D - E network. */
	170	sprintf (qbuf, "%u.%u.%u.%u.in-addr.arpa", net_bytes[3], net_bytes[2],
	171	net_bytes[1], net_bytes[0]);
	172	break;
	173	}
	174
	175	anslen = res_query (qbuf, C_IN, T_PTR, (u_char *) &net_buffer,
	176	sizeof (querybuf));
	177	if (anslen < 0)
67479a70 UD	178	{
	179	/* Nothing found. */
	180	*errnop = errno;
	181	return (errno == ECONNREFUSED
	182	\|\| errno == EPFNOSUPPORT
	183	\|\| errno == EAFNOSUPPORT)
	184	? NSS_STATUS_UNAVAIL : NSS_STATUS_NOTFOUND;
	185	}
5f0e6fc7 RM	186
	187	status = getanswer_r (&net_buffer, anslen, result, buffer, buflen, BYADDR);
	188	if (status == NSS_STATUS_SUCCESS)
	189	{
	190	/* Strip trailing zeros. */
	191	unsigned int u_net = net; /* Maybe net should be unsigned? */
	192
	193	while ((u_net & 0xff) == 0 && u_net != 0)
	194	u_net >>= 8;
	195	result->n_net = u_net;
	196	}
	197
	198	return status;
	199	}
	200
	201
	202	#undef offsetof
	203	#define offsetof(Type, Member) ((size_t) &((Type *) NULL)->Member)
	204
84384f5b	205	static enum nss_status
5f0e6fc7	206	getanswer_r (const querybuf answer, int anslen, struct netent result,
df4ef2ab	207	char *buffer, size_t buflen, lookup_method net_i)
5f0e6fc7 RM	208	{
	209	/*
	210	* Find first satisfactory answer
	211	*
	212	* answer --> +------------+ ( MESSAGE )
	213	* \| Header \|
	214	* +------------+
	215	* \| Question \| the question for the name server
	216	* +------------+
	217	* \| Answer \| RRs answering the question
	218	* +------------+
	219	* \| Authority \| RRs pointing toward an authority
	220	* \| Additional \| RRs holding additional information
	221	* +------------+
	222	*/
	223	struct net_data
	224	{
	225	char *aliases[MAX_NR_ALIASES];
	226	char linebuffer[0];
	227	} net_data = (struct net_data ) buffer;
	228	int linebuflen = buflen - offsetof (struct net_data, linebuffer);
	229	const char *end_of_message = &answer->buf[anslen];
	230	const HEADER *header_pointer = &answer->hdr;
	231	/* #/records in the answer section. */
	232	int answer_count = ntohs (header_pointer->ancount);
	233	/* #/entries in the question section. */
	234	int question_count = ntohs (header_pointer->qdcount);
	235	char *bp = net_data->linebuffer;
	236	const char *cp = &answer->buf[HFIXEDSZ];
	237	char **alias_pointer;
	238	int have_answer;
	239	char *ans;
8d8c6efa	240	u_char packtmp[NS_MAXCDNAME];
5f0e6fc7 RM	241
5f0e6fc7 RM	242	if (question_count == 0)
7ef90c15 UD	243	{
	244	/* FIXME: the Sun version uses for host name lookup an additional
	245	parameter for pointing to h_errno. this is missing here.
	246	OSF/1 has a per-thread h_errno variable. */
	247	if (header_pointer->aa != 0)
	248	{
	249	__set_h_errno (HOST_NOT_FOUND);
	250	return NSS_STATUS_NOTFOUND;
	251	}
	252	else
	253	{
	254	__set_h_errno (TRY_AGAIN);
	255	return NSS_STATUS_TRYAGAIN;
	256	}
	257	}
5f0e6fc7 RM	258
	259	/* Skip the question part. */
	260	while (question_count-- > 0)
	261	cp += __dn_skipname (cp, end_of_message) + QFIXEDSZ;
	262
	263	alias_pointer = result->n_aliases = &net_data->aliases[0];
	264	*alias_pointer = NULL;
	265	have_answer = 0;
	266	ans = NULL;
	267
	268	while (--answer_count >= 0 && cp < end_of_message)
	269	{
	270	int n = dn_expand (answer->buf, end_of_message, cp, bp, linebuflen);
	271	int type, class;
	272
8d8c6efa UD	273	n = __ns_name_unpack (answer->buf, end_of_message, cp,
	274	packtmp, sizeof packtmp);
	275	if (n != -1 && __ns_name_ntop (packtmp, bp, linebuflen) == -1)
	276	{
	277	if (errno == EMSGSIZE)
	278	{
	279	errno = ERANGE;
	280	return NSS_STATUS_TRYAGAIN;
	281	}
	282
	283	n = -1;
	284	}
	285
	286	if (n > 0 && bp[0] == '.')
	287	bp[0] = '\0';
	288
5f0e6fc7 RM	289	if (n < 0 \|\| res_dnok (bp) == 0)
	290	break;
	291	cp += n;
	292	ans = strdupa (bp);
	293	GETSHORT (type, cp);
	294	GETSHORT (class, cp);
	295	cp += INT32SZ; /* TTL */
	296	GETSHORT (n, cp);
	297
	298	if (class == C_IN && type == T_PTR)
	299	{
8d8c6efa UD	300	n = __ns_name_unpack (answer->buf, end_of_message, cp,
	301	packtmp, sizeof packtmp);
	302	if (n != -1 && __ns_name_ntop (packtmp, bp, linebuflen) == -1)
	303	{
	304	if (errno == EMSGSIZE)
	305	{
	306	errno = ERANGE;
	307	return NSS_STATUS_TRYAGAIN;
	308	}
	309
	310	n = -1;
	311	}
	312
5f0e6fc7 RM	313	if (n < 0 \|\| !res_hnok (bp))
	314	{
	315	/* XXX What does this mean? The original form from bind
	316	returns NULL. Incrementing cp has no effect in any case.
	317	What should I return here. ??? */
	318	cp += n;
	319	return NSS_STATUS_UNAVAIL;
	320	}
	321	cp += n;
	322	*alias_pointer++ = bp;
	323	bp += strlen (bp) + 1;
	324	result->n_addrtype = class == C_IN ? AF_INET : AF_UNSPEC;
	325	++have_answer;
	326	}
	327	}
	328
	329	if (have_answer)
	330	{
	331	char *tmp;
	332	int len;
	333	char in, cp, rp, wp;
	334	int cnt, first_flag;
	335
	336	*alias_pointer = NULL;
	337	switch (net_i)
	338	{
	339	case BYADDR:
	340	result->n_name = result->n_aliases[0];
	341	result->n_net = 0L;
	342	break;
	343	case BYNAME:
	344	len = strlen (result->n_aliases[0]);
	345	tmp = (char *) alloca (len + 1);
	346	tmp[len] = 0;
	347	wp = &tmp[len - 1];
	348
	349	rp = in = result->n_aliases[0];
	350	result->n_name = ans;
	351
	352	first_flag = 1;
	353	for (cnt = 0; cnt < 4; ++cnt)
	354	{
	355	char *startp;
	356
	357	startp = rp;
	358	while (*rp != '.')
	359	++rp;
	360	if (rp - startp > 1 \|\| *startp != '0' \|\| !first_flag)
	361	{
	362	first_flag = 0;
	363	if (cnt > 0)
	364	*wp-- = '.';
	365	cp = rp;
	366	while (cp > startp)
	367	wp-- = --cp;
	368	}
	369	in = rp + 1;
	370	}
	371
	372	result->n_net = inet_network (wp);
	373	break;
	374	}
	375
	376	++result->n_aliases;
377	return NSS_STATUS_SUCCESS;
378	}
379
a68b0d31	380	__set_h_errno (TRY_AGAIN);
5f0e6fc7 RM	381	return NSS_STATUS_TRYAGAIN;
5f0e6fc7 RM	382	}