Make ssh-add check file permissions before attempting to load private

key files multiple times; it will fail anyway and this prevents confusing
multiple prompts and warnings.  mindrot #1138, ok djm@

3 files changed, 17 insertions, 7 deletions

diff --git a/usr.bin/ssh/authfile.c b/usr.bin/ssh/authfile.c
index 65f392506a5..1a18b922004 100644
--- a/usr.bin/ssh/authfile.c
+++ b/usr.bin/ssh/authfile.c
@@ -36,7 +36,7 @@
  */
 
 #include "includes.h"
-RCSID("$OpenBSD: authfile.c,v 1.62 2006/02/20 17:19:54 stevesk Exp $");
+RCSID("$OpenBSD: authfile.c,v 1.63 2006/03/13 10:26:52 dtucker Exp $");
 
 #include <sys/types.h>
 #include <sys/stat.h>
@@ -510,7 +510,7 @@ key_load_private_pem(int fd, int type, const char *passphrase,
 	return prv;
 }
 
-static int
+int
 key_perm_ok(int fd, const char *filename)
 {
 	struct stat st;
diff --git a/usr.bin/ssh/authfile.h b/usr.bin/ssh/authfile.h
index 7f92701ec05..a16caa7a8fc 100644
--- a/usr.bin/ssh/authfile.h
+++ b/usr.bin/ssh/authfile.h
@@ -1,4 +1,4 @@
-/*	$OpenBSD: authfile.h,v 1.10 2002/05/23 19:24:30 markus Exp $	*/
+/*	$OpenBSD: authfile.h,v 1.11 2006/03/13 10:26:52 dtucker Exp $	*/
 
 /*
  * Author: Tatu Ylonen <ylo@cs.hut.fi>
@@ -21,5 +21,6 @@ Key	*key_load_public_type(int, const char *, char **);
 Key	*key_load_private(const char *, const char *, char **);
 Key	*key_load_private_type(int, const char *, const char *, char **);
 Key	*key_load_private_pem(int, int, const char *, char **);
+int	 key_perm_ok(int, const char *);
 
 #endif
diff --git a/usr.bin/ssh/ssh-add.c b/usr.bin/ssh/ssh-add.c
index 2e1998b78ad..1bf5744cf3a 100644
--- a/usr.bin/ssh/ssh-add.c
+++ b/usr.bin/ssh/ssh-add.c
@@ -35,7 +35,7 @@
  */
 
 #include "includes.h"
-RCSID("$OpenBSD: ssh-add.c,v 1.75 2006/02/20 17:19:54 stevesk Exp $");
+RCSID("$OpenBSD: ssh-add.c,v 1.76 2006/03/13 10:26:52 dtucker Exp $");
 
 #include <sys/types.h>
 #include <sys/stat.h>
@@ -127,16 +127,25 @@ delete_all(AuthenticationConnection *ac)
 static int
 add_file(AuthenticationConnection *ac, const char *filename)
 {
-	struct stat st;
 	Key *private;
 	char *comment = NULL;
 	char msg[1024];
-	int ret = -1;
+	int fd, perms_ok, ret = -1;
 
-	if (stat(filename, &st) < 0) {
+	if ((fd = open(filename, 0)) < 0) {
 		perror(filename);
 		return -1;
 	}
+
+	/*
+	 * Since we'll try to load a keyfile multiple times, permission errors
+	 * will occur multiple times, so check perms first and bail if wrong.
+	 */
+	perms_ok = key_perm_ok(fd, filename);
+	close(fd);
+	if (!perms_ok)
+		return -1;
+
 	/* At first, try empty passphrase */
 	private = key_load_private(filename, "", &comment);
 	if (comment == NULL)