Sat Jul 27 02:58:49 1996 Roland McGrath <roland@delasyd.gnu.ai.mit.edu>cvs/libc-960727

	* elf/rtld.c (dl_main): Take new option --verify when run directly.
	In verify mode, exit with status zero iff the argument object's
	PT_INTERP matches argv[0].
	* elf/ldd.sh.in: Use ${RTLD} --verify and only run the program if it
	exits with zero status.  This makes `ldd' secure again.

Fri Jul 26 22:49:58 1996  Ulrich Drepper  <drepper@cygnus.com>

	* elf/rtld.c (dl_main): Implement LD_TRACE_LOADED_OBJECTS
	environment variable handling.  This makes the dynamic linker
	only print loaded libraries and quit.

	* elf/ldd.sh.in: Don't use `rtld --list' but instead
	LD_TRACE_LOADED_OBJECTS environment variable to print needed
	objects.

Sat Jul 27 02:03:26 1996  Roland McGrath  <roland@delasyd.gnu.ai.mit.edu>

	* db/makedb.c (main): Print version on stdout, not stderr.  Don't exit
	after printing version until after doing usage for --help.
	(long_options, main, usage): Rename -l/--lowercase option to
	-f/--fold-case (-f matches sort).

Sat Jul 27 04:32:31 1996  Ulrich Drepper  <drepper@cygnus.com>

	* db/makedb.c: New file.  Implement program to create simple <db.h>
	database from textual input.  This will be used for nss_db.

Sat Jul 27 01:24:05 1996  Roland McGrath  <roland@delasyd.gnu.ai.mit.edu>

	* sunrpc/rpc/auth_unix.h: Fix misapplied patches in last changes.
	* sunrpc/rpc/pmap_clnt.h: Likewise.
	* sunrpc/rpc/auth.h: Likewise.
	* sunrpc/rpc/pmap_rmt.h: Likewise.
	* sunrpc/rpc/rpc_msg.h: Likewise.

Sat Jul 27 04:37:34 1996  Ulrich Drepper  <drepper@cygnus.com>

	* string/string.h (strndupa): Change to use return value of
	`memcpy' for more performance.
	* string/strndup.c: Likewise.

	* string/string.h (strdupa): Don't call __builtin_alloca in argument.
	This might lead to problems.
	(strndupa): Likewise.

2 files changed, 31 insertions, 6 deletions

diff --git a/elf/ldd.sh.in b/elf/ldd.sh.in
index ed43789cfa..82946fd535 100644
--- a/elf/ldd.sh.in
+++ b/elf/ldd.sh.in
@@ -17,7 +17,11 @@ case $# in
   /*) file="$1" ;;
   *) file="./$1" ;;
   esac
-  exec ${RTLD} --list "$file" && exit 1
+  if ${RTLD} --verify "$file"; then
+    LD_TRACE_LOADED_OBJECTS=1 exec "$file" && exit 1
+  else
+    echo '	not a dynamic executable'
+  fi
   exit ;;
 *)
   set -e	# Bail out immediately if ${RTLD} loses on any argument.
@@ -27,7 +31,11 @@ case $# in
     /*) file="$file" ;;
     *) file="./$file" ;;
     esac
-    ${RTLD} --list "$file"
+    if ${RTLD} --verify "$file"; then
+      LD_TRACE_LOADED_OBJECTS=1 "$file"
+    else
+      echo '	not a dynamic executable'
+    fi
   done
 esac
 
diff --git a/elf/rtld.c b/elf/rtld.c
index 66cfa60ceb..35a94b24cc 100644
--- a/elf/rtld.c
+++ b/elf/rtld.c
@@ -127,7 +127,7 @@ dl_main (const ElfW(Phdr) *phdr,
   const ElfW(Phdr) *ph;
   struct link_map *l;
   int lazy;
-  int list_only = 0;
+  enum { normal, list, verify } mode = normal;
   struct link_map **preloads;
   unsigned int npreloads;
 
@@ -150,7 +150,7 @@ dl_main (const ElfW(Phdr) *phdr,
 	 installing it.  */
       if (_dl_argc < 2)
 	_dl_sysdep_fatal ("\
-Usage: ld.so [--list] EXECUTABLE-FILE [ARGS-FOR-PROGRAM...]\n\
+Usage: ld.so [--list|--verify] EXECUTABLE-FILE [ARGS-FOR-PROGRAM...]\n\
 You have invoked `ld.so', the helper program for shared library executables.\n\
 This program usually lives in the file `/lib/ld.so', and special directives\n\
 in executable files using ELF shared libraries tell the system's program\n\
@@ -169,7 +169,15 @@ of this helper program; chances are you did not intend to run this program.\n",
 
       if (! strcmp (_dl_argv[1], "--list"))
 	{
-	  list_only = 1;
+	  mode = list;
+
+	  ++_dl_skip_args;
+	  --_dl_argc;
+	  ++_dl_argv;
+	}
+      else if (! strcmp (_dl_argv[1], "--verify"))
+	{
+	  mode = verify;
 
 	  ++_dl_skip_args;
 	  --_dl_argc;
@@ -235,6 +243,12 @@ of this helper program; chances are you did not intend to run this program.\n",
   else
     assert (_dl_rtld_map.l_libname); /* How else did we get here?  */
 
+  if (mode == verify)
+    /* We were called just to verify that this is a dynamic executable
+       using us as the program interpreter.  */
+    _exit (strcmp (_dl_rtld_map.l_libname, _dl_rtld_map.l_name)
+	   ? EXIT_FAILURE : EXIT_SUCCESS);
+
   /* Extract the contents of the dynamic section for easy access.  */
   elf_get_dynamic_info (l->l_ld, l->l_info);
   if (l->l_info[DT_HASH])
@@ -326,7 +340,10 @@ of this helper program; chances are you did not intend to run this program.\n",
 	}
     }
 
-  if (list_only)
+  if (mode == normal && getenv ("LD_TRACE_LOADED_OBJECTS") != NULL)
+    mode = list;
+
+  if (mode != normal)
     {
       /* We were run just to list the shared libraries.  It is
 	 important that we do this before real relocation, because the