commit 7267341ec1b5c591c2e7946d0604d3cf1423db7d

Author: Florian Weimer <fweimer@redhat.com>

Date:   Tue Aug 30 10:02:49 2022 +0200

    nss_dns: Remove remnants of IPv6 address mapping

    res_use_inet6 always returns false since commit 3f8b44be0a658266adff5

    ("resolv: Remove support for RES_USE_INET6 and the inet6 option").

    Reviewed-by: Siddhesh Poyarekar <siddhesh@sourceware.org>

    (cherry picked from commit a7fc30b522a0cd7c8c5e7e285b9531b704e02f04)

diff --git a/resolv/README b/resolv/README

index 514e9bb617e710f1..2146bc3b27a6dc56 100644

--- a/resolv/README

+++ b/resolv/README

@@ -146,6 +146,3 @@ res_libc.c is home-brewn, although parts of it are taken from res_data.c.

 res_hconf.c and res_hconf.h were contributed by David Mosberger, and

 do not come from BIND.

-

-The files gethnamaddr.c, mapv4v6addr.h and mapv4v6hostent.h are

-leftovers from BIND 4.9.7.

diff --git a/resolv/mapv4v6addr.h b/resolv/mapv4v6addr.h

deleted file mode 100644

index 7f85f7d5e393ec5f..0000000000000000

--- a/resolv/mapv4v6addr.h

+++ /dev/null

@@ -1,69 +0,0 @@

-/*

- * ++Copyright++ 1985, 1988, 1993

- * -

- * 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.

- * 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--

- */

-

-#include <string.h>

-#include <arpa/nameser.h>

-

-static void

-map_v4v6_address (const char *src, char *dst)

-{

-  u_char *p = (u_char *) dst;

-  int i;

-

-  /* Move the IPv4 part to the right position.  */

-  memcpy (dst + 12, src, INADDRSZ);

-

-  /* Mark this ipv6 addr as a mapped ipv4. */

-  for (i = 0; i < 10; i++)

-    *p++ = 0x00;

-  *p++ = 0xff;

-  *p = 0xff;

-}

diff --git a/resolv/mapv4v6hostent.h b/resolv/mapv4v6hostent.h

deleted file mode 100644

index c11038adf33f154d..0000000000000000

--- a/resolv/mapv4v6hostent.h

+++ /dev/null

@@ -1,84 +0,0 @@

-/*

- * ++Copyright++ 1985, 1988, 1993

- * -

- * 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.

- * 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--

- */

-

-#include <arpa/nameser.h>

-#include <sys/socket.h>

-

-typedef union {

-    int32_t al;

-    char ac;

-} align;

-

-static int

-map_v4v6_hostent (struct hostent *hp, char **bpp, int *lenp)

-{

-  char **ap;

-

-  if (hp->h_addrtype != AF_INET || hp->h_length != INADDRSZ)

-    return 0;

-  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.  */

-	return 1;

-      *bpp += i;

-      *lenp -= i;

-      map_v4v6_address (*ap, *bpp);

-      *ap = *bpp;

-      *bpp += IN6ADDRSZ;

-      *lenp -= IN6ADDRSZ;

-    }

-  return 0;

-}

diff --git a/resolv/nss_dns/dns-host.c b/resolv/nss_dns/dns-host.c

index 2cd7170f20b60588..f8dc5a0a7d1eb156 100644

--- a/resolv/nss_dns/dns-host.c

+++ b/resolv/nss_dns/dns-host.c

@@ -88,10 +88,6 @@

 #include <resolv/resolv-internal.h>

 #include <resolv/resolv_context.h>

-/* Get implementations of some internal functions.  */

-#include <resolv/mapv4v6addr.h>

-#include <resolv/mapv4v6hostent.h>

-

 #define RESOLVSORT

 #if PACKETSZ > 65536

@@ -117,7 +113,7 @@ static enum nss_status getanswer_r (struct resolv_context *ctx,

 				    const char *qname, int qtype,

 				    struct hostent *result, char *buffer,

 				    size_t buflen, int *errnop, int *h_errnop,

-				    int map, int32_t *ttlp, char **canonp);

+				    int32_t *ttlp, char **canonp);

 static enum nss_status getanswer_ptr (unsigned char *packet, size_t packetlen,

 				      struct alloc_buffer *abuf,

 				      char **hnamep, int *errnop,

@@ -198,7 +194,6 @@ gethostbyname3_context (struct resolv_context *ctx,

   char tmp[NS_MAXDNAME];

   int size, type, n;

   const char *cp;

-  int map = 0;

   int olderr = errno;

   enum nss_status status;

@@ -259,32 +254,12 @@ gethostbyname3_context (struct resolv_context *ctx,

 	*errnop = EAGAIN;

       else

 	__set_errno (olderr);

-

-      /* If we are looking for an IPv6 address and mapping is enabled

-	 by having the RES_USE_INET6 bit in _res.options set, we try

-	 another lookup.  */

-      if (af == AF_INET6 && res_use_inet6 ())

-	n = __res_context_search (ctx, name, C_IN, T_A, host_buffer.buf->buf,

-				  host_buffer.buf != orig_host_buffer

-				  ? MAXPACKET : 1024, &host_buffer.ptr,

-				  NULL, NULL, NULL, NULL);

-

-      if (n < 0)

-	{

-	  if (host_buffer.buf != orig_host_buffer)

-	    free (host_buffer.buf);

-	  return status;

-	}

-

-      map = 1;

-

-      result->h_addrtype = AF_INET;

-      result->h_length = INADDRSZ;

     }

+  else

+    status = getanswer_r

+      (ctx, host_buffer.buf, n, name, type, result, buffer, buflen,

+       errnop, h_errnop, ttlp, canonp);

-  status = getanswer_r

-    (ctx, host_buffer.buf, n, name, type, result, buffer, buflen,

-     errnop, h_errnop, map, ttlp, canonp);

   if (host_buffer.buf != orig_host_buffer)

     free (host_buffer.buf);

   return status;

@@ -330,13 +305,8 @@ _nss_dns_gethostbyname_r (const char *name, struct hostent *result,

       *h_errnop = NETDB_INTERNAL;

       return NSS_STATUS_UNAVAIL;

     }

-  status = NSS_STATUS_NOTFOUND;

-  if (res_use_inet6 ())

-    status = gethostbyname3_context (ctx, name, AF_INET6, result, buffer,

-				     buflen, errnop, h_errnop, NULL, NULL);

-  if (status == NSS_STATUS_NOTFOUND)

-    status = gethostbyname3_context (ctx, name, AF_INET, result, buffer,

-				     buflen, errnop, h_errnop, NULL, NULL);

+  status = gethostbyname3_context (ctx, name, AF_INET, result, buffer,

+				   buflen, errnop, h_errnop, NULL, NULL);

   __resolv_context_put (ctx);

   return status;

 }

@@ -649,7 +619,7 @@ static enum nss_status

 getanswer_r (struct resolv_context *ctx,

 	     const querybuf *answer, int anslen, const char *qname, int qtype,

 	     struct hostent *result, char *buffer, size_t buflen,

-	     int *errnop, int *h_errnop, int map, int32_t *ttlp, char **canonp)

+	     int *errnop, int *h_errnop, int32_t *ttlp, char **canonp)

 {

   struct host_data

   {

@@ -665,7 +635,6 @@ getanswer_r (struct resolv_context *ctx,

   char *bp, **ap, **hap;

   char tbuf[MAXDNAME];

   u_char packtmp[NS_MAXCDNAME];

-  int have_to_map = 0;

   uintptr_t pad = -(uintptr_t) buffer % __alignof__ (struct host_data);

   buffer += pad;

   buflen = buflen > pad ? buflen - pad : 0;

@@ -846,9 +815,7 @@ getanswer_r (struct resolv_context *ctx,

 	  continue;

 	}

-      if (type == T_A && qtype == T_AAAA && map)

-	have_to_map = 1;

-      else if (__glibc_unlikely (type != qtype))

+      if (__glibc_unlikely (type != qtype))

 	{

 	  cp += n;

 	  continue;			/* XXX - had_error++ ? */

@@ -945,9 +912,6 @@ getanswer_r (struct resolv_context *ctx,

 	  linebuflen -= n;

 	}

-      if (have_to_map)

-	if (map_v4v6_hostent (result, &bp, &linebuflen))

-	  goto too_small;

       *h_errnop = NETDB_SUCCESS;

       return NSS_STATUS_SUCCESS;

     }