resolv: Move ns_makecanon into its own file, and into libc

But only as an internal symbol, __libc_ns_makecanon.  The libresolv
ABI is preserved.  This is because the function is deprecated, and
it does not make sense to add new symbol versions for deprecated
functions.

Also reformat the implementation to GNU style.

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

diff --git a/include/arpa/nameser.h b/include/arpa/nameser.h
index eff25178c8318b6e1bc33b55e7f6572ebd4027f9..a529cc86d369265fe47eb690e7dc83322bb0199f 100644 (file)
--- a/include/arpa/nameser.h
+++ b/include/arpa/nameser.h
@@ -69,9 +69,10 @@ libresolv_hidden_proto (ns_sprintrr)
 libresolv_hidden_proto (ns_sprintrrf)
 libresolv_hidden_proto (ns_samedomain)
 libresolv_hidden_proto (ns_samename)
-libresolv_hidden_proto (ns_makecanon)
 libresolv_hidden_proto (ns_format_ttl)
 
+extern __typeof (ns_makecanon) __libc_ns_makecanon;
+libc_hidden_proto (__libc_ns_makecanon)
 extern __typeof (ns_name_compress) __ns_name_compress;
 libc_hidden_proto (__ns_name_compress)
 extern __typeof (ns_name_ntop) __ns_name_ntop;

diff --git a/resolv/Makefile b/resolv/Makefile
index 221bdc153d1f908855f0bde3345a521ec9fac38a..d1ad5e4cba340f403e1401a9a7fe5483288cc243 100644 (file)
--- a/resolv/Makefile
+++ b/resolv/Makefile
@@ -35,6 +35,7 @@ routines := \
   inet_addr \
   inet_ntop \
   inet_pton \
+  ns_makecanon \
   ns_name_compress \
   ns_name_ntop \
   ns_name_pack \
@@ -151,6 +152,7 @@ libresolv-routines := \
   res_mkquery \
   res_query \
   res_send \
+  resolv-deprecated \
   # libresolv-routines
 
 $(libanl-routines-var) += \

diff --git a/resolv/Versions b/resolv/Versions
index fc14cdb701e1d146ab26452835adcd51574feafd..93078de25c418315a31a7e208ef7aa3925142c1e 100644 (file)
--- a/resolv/Versions
+++ b/resolv/Versions
@@ -72,6 +72,7 @@ libc {
     __inet_pton_length;
     __libc_dn_expand;
     __libc_dn_skipname;
+    __libc_ns_makecanon;
     __libc_res_dnok;
     __libc_res_hnok;
     __ns_name_compress;

diff --git a/resolv/ns_makecanon.c b/resolv/ns_makecanon.c
new file mode 100644 (file)
index 0000000..a6c3c27
--- /dev/null
+++ b/resolv/ns_makecanon.c
@@ -0,0 +1,50 @@
+/* Add missing "." to domain names.
+ * Copyright (c) 2004 by Internet Systems Consortium, Inc. ("ISC")
+ * Copyright (c) 1995,1999 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 <errno.h>
+#include <string.h>
+
+/* Make a canonical copy of domain name SRC in DST.  Behavior:
+      foo -> foo.
+      foo. -> foo.
+      foo.. -> foo.
+      foo\. -> foo\..
+      foo\\. -> foo\\.  */
+int
+__libc_ns_makecanon (const char *src, char *dst, size_t dstsize)
+{
+  size_t n = strlen (src);
+
+  if (n + sizeof "." > dstsize) /* sizeof == 2.  */
+    {
+      __set_errno (EMSGSIZE);
+      return -1;
+    }
+  strcpy (dst, src);
+  while (n >= 1U && dst[n - 1] == '.')   /* Ends in ".".  */
+    if (n >= 2U && dst[n - 2] == '\\' && /* Ends in "\.".  */
+        (n < 3U || dst[n - 3] != '\\'))  /* But not "\\.".  */
+      break;
+    else
+      dst[--n] = '\0';
+  dst[n++] = '.';
+  dst[n] = '\0';
+  return 0;
+}
+libc_hidden_def (__libc_ns_makecanon)

diff --git a/resolv/ns_samedomain.c b/resolv/ns_samedomain.c
index 5d1bf39fc7280d3b44d87122fd37b9244daa2875..cfff2516b075c4e71ff3ac9d711faa423154d09c 100644 (file)
--- a/resolv/ns_samedomain.c
+++ b/resolv/ns_samedomain.c
@@ -143,40 +143,6 @@ ns_subdomain(const char *a, const char *b) {
        return (ns_samename(a, b) != 1 && ns_samedomain(a, b));
 }
 
-/*%
- *     make a canonical copy of domain name "src"
- *
- * notes:
- * \code
- *     foo -> foo.
- *     foo. -> foo.
- *     foo.. -> foo.
- *     foo\. -> foo\..
- *     foo\\. -> foo\\.
- * \endcode
- */
-
-int
-ns_makecanon(const char *src, char *dst, size_t dstsize) {
-       size_t n = strlen(src);
-
-       if (n + sizeof "." > dstsize) {                 /*%< Note: sizeof == 2 */
-               __set_errno (EMSGSIZE);
-               return (-1);
-       }
-       strcpy(dst, src);
-       while (n >= 1U && dst[n - 1] == '.')            /*%< Ends in "." */
-               if (n >= 2U && dst[n - 2] == '\\' &&    /*%< Ends in "\." */
-                   (n < 3U || dst[n - 3] != '\\'))     /*%< But not "\\." */
-                       break;
-               else
-                       dst[--n] = '\0';
-       dst[n++] = '.';
-       dst[n] = '\0';
-       return (0);
-}
-libresolv_hidden_def (ns_makecanon)
-
 /*%
  *     determine whether domain name "a" is the same as domain name "b"
  *
@@ -190,8 +156,8 @@ int
 ns_samename(const char *a, const char *b) {
        char ta[NS_MAXDNAME], tb[NS_MAXDNAME];
 
-       if (ns_makecanon(a, ta, sizeof ta) < 0 ||
-           ns_makecanon(b, tb, sizeof tb) < 0)
+       if (__libc_ns_makecanon(a, ta, sizeof ta) < 0 ||
+           __libc_ns_makecanon(b, tb, sizeof tb) < 0)
                return (-1);
        if (strcasecmp(ta, tb) == 0)
                return (1);

diff --git a/resolv/resolv-deprecated.c b/resolv/resolv-deprecated.c
new file mode 100644 (file)
index 0000000..cbd1078
--- /dev/null
+++ b/resolv/resolv-deprecated.c
@@ -0,0 +1,35 @@
+/* Forwarders for deprecated libresolv functions which are implemented in libc.
+   Copyright (C) 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/>.  */
+
+/* Some functions are used by the stub resolver implementation
+   internally and thus have to be located in libc.  They have been
+   historially exported for application use as well.  However, the
+   stub resolver dependency on those functions is not intrinsic to
+   what the stub resolver does, and it is possible that a future
+   version of the stub resolver will not need them anymore.  The
+   public symbols for these functions remain in libresolv, and are not
+   moved to libc, to avoid adding new symbol versions for legacy
+   functions.  */
+
+#include <arpa/nameser.h>
+
+int
+ns_makecanon (const char *src, char *dst, size_t dstsize)
+{
+  return __libc_ns_makecanon (src, dst, dstsize);
+}