resolv: Move res_nameinquery to its own file and into libc

And reformat to GNU style.

This deprecated function is used in the implementation of the stub
resolver (for now).  Keep the public symbol in libresolv for now
(so that no new symbol version is needed), and add a forwarder to
libresolv.

Reviewed-by: Carlos O'Donell <carlos@redhat.com>
Tested-by: Carlos O'Donell <carlos@redhat.com>

5 files changed, 126 insertions, 42 deletions

diff --git a/resolv/Makefile b/resolv/Makefile
index 744da95..c4c59dc 100644
--- a/resolv/Makefile
+++ b/resolv/Makefile
@@ -52,6 +52,7 @@ routines := \
   res_hconf \
   res_init \
   res_libc \
+  res_nameinquery \
   res_randomid \
   resolv_conf \
   resolv_context \
diff --git a/resolv/Versions b/resolv/Versions
index 2201d42..f348279 100644
--- a/resolv/Versions
+++ b/resolv/Versions
@@ -76,6 +76,7 @@ libc {
     __libc_ns_samename;
     __libc_res_dnok;
     __libc_res_hnok;
+    __libc_res_nameinquery;
     __ns_name_compress;
     __ns_name_ntop;
     __ns_name_pack;
diff --git a/resolv/res_nameinquery.c b/resolv/res_nameinquery.c
new file mode 100644
index 0000000..c8404ea
--- /dev/null
+++ b/resolv/res_nameinquery.c
@@ -0,0 +1,115 @@
+/* Check if a DNS packet matches a specific DNS query.
+   Copyright (C) 2016-2021 Free Software Foundation, Inc.
+   This file is part of the GNU C Library.
+
+   The GNU C Library is free software; you can redistribute it and/or
+   modify it under the terms of the GNU Lesser General Public
+   License as published by the Free Software Foundation; either
+   version 2.1 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
+   Lesser General Public License for more details.
+
+   You should have received a copy of the GNU Lesser General Public
+   License along with the GNU C Library; if not, see
+   <https://www.gnu.org/licenses/>.  */
+
+/*
+ * Copyright (c) 1985, 1989, 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.
+ */
+
+/*
+ * Portions Copyright (c) 1996-1999 by Internet Software Consortium.
+ *
+ * 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.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS" AND INTERNET SOFTWARE CONSORTIUM DISCLAIMS
+ * ALL WARRANTIES WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES
+ * OF MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL INTERNET SOFTWARE
+ * CONSORTIUM 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.
+ */
+
+#include <arpa/nameser.h>
+#include <resolv.h>
+
+/* Author: paul vixie, 29may94.  */
+int
+__libc_res_nameinquery (const char *name, int type, int class,
+                        const unsigned char *buf, const unsigned char *eom)
+{
+  const unsigned char *cp = buf + HFIXEDSZ;
+  int qdcount = ntohs (((HEADER *) buf)->qdcount);
+
+  while (qdcount-- > 0)
+    {
+      char tname[MAXDNAME+1];
+      int n, ttype, tclass;
+
+      n = __libc_dn_expand (buf, eom, cp, tname, sizeof tname);
+      if (n < 0)
+        return -1;
+      cp += n;
+      if (cp + 2 * INT16SZ > eom)
+        return -1;
+      NS_GET16 (ttype, cp);
+      NS_GET16 (tclass, cp);
+      if (ttype == type && tclass == class
+          && __libc_ns_samename (tname, name) == 1)
+        return 1;
+    }
+  return 0;
+}
+libc_hidden_def (__libc_res_nameinquery)
diff --git a/resolv/res_send.c b/resolv/res_send.c
index dfea9fc..a5a33e6 100644
--- a/resolv/res_send.c
+++ b/resolv/res_send.c
@@ -191,47 +191,6 @@ static int		send_dg(res_state, const u_char *, int,
 				u_char **, int *, int *, int *);
 static int		sock_eq(struct sockaddr_in6 *, struct sockaddr_in6 *);
 
-/* Public. */
-
-/* int
- * res_nameinquery(name, type, class, buf, eom)
- *	look for (name,type,class) in the query section of packet (buf,eom)
- * requires:
- *	buf + HFIXEDSZ <= eom
- * returns:
- *	-1 : format error
- *	0  : not found
- *	>0 : found
- * author:
- *	paul vixie, 29may94
- */
-int
-res_nameinquery(const char *name, int type, int class,
-		const u_char *buf, const u_char *eom)
-{
-	const u_char *cp = buf + HFIXEDSZ;
-	int qdcount = ntohs(((HEADER*)buf)->qdcount);
-
-	while (qdcount-- > 0) {
-		char tname[MAXDNAME+1];
-		int n, ttype, tclass;
-
-		n = __libc_dn_expand (buf, eom, cp, tname, sizeof tname);
-		if (n < 0)
-			return (-1);
-		cp += n;
-		if (cp + 2 * INT16SZ > eom)
-			return (-1);
-		NS_GET16(ttype, cp);
-		NS_GET16(tclass, cp);
-		if (ttype == type && tclass == class
-		    && __libc_ns_samename (tname, name) == 1)
-			return (1);
-	}
-	return (0);
-}
-libresolv_hidden_def (res_nameinquery)
-
 /* Returns a shift value for the name server index.  Used to implement
    RES_ROTATE.  */
 static unsigned int
@@ -337,7 +296,7 @@ res_queriesmatch(const u_char *buf1, const u_char *eom1,
 			return (-1);
 		NS_GET16(ttype, cp);
 		NS_GET16(tclass, cp);
-		if (!res_nameinquery(tname, ttype, tclass, buf2, eom2))
+		if (!__libc_res_nameinquery (tname, ttype, tclass, buf2, eom2))
 			return (0);
 	}
 	return (1);
diff --git a/resolv/resolv-deprecated.c b/resolv/resolv-deprecated.c
index d8344f8..0fe9e4f 100644
--- a/resolv/resolv-deprecated.c
+++ b/resolv/resolv-deprecated.c
@@ -27,6 +27,7 @@
    functions.  */
 
 #include <arpa/nameser.h>
+#include <resolv.h>
 
 int
 ns_makecanon (const char *src, char *dst, size_t dstsize)
@@ -39,3 +40,10 @@ ns_samename (const char *a, const char *b)
 {
   return __libc_ns_samename (a, b);
 }
+
+int
+res_nameinquery (const char *name, int type, int class,
+                 const unsigned char *buf, const unsigned char *eom)
+{
+  return __libc_res_nameinquery (name, type, class, buf, eom);
+}