- markus@cvs.openbsd.org 2007/08/15 08:14:46

     [clientloop.c]
     do NOT fall back to the trused x11 cookie if generation of an untrusted
     cookie fails; from security-alert at sun.com; ok dtucker

diff --git a/ChangeLog b/ChangeLog
index a99a6af2a00056e1179eea41d98df2c909582628..eee33e3644e06de756594d52e7c709a24d09e99c 100644 (file)
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,10 @@
+20070815
+ - (dtucker) OpenBSD CVS Sync
+   - markus@cvs.openbsd.org 2007/08/15 08:14:46
+     [clientloop.c]
+     do NOT fall back to the trused x11 cookie if generation of an untrusted
+     cookie fails; from security-alert at sun.com; ok dtucker
+
 20070813
  - (dtucker) [session.c] Bug #1339: ensure that pam_setcred() is always
    called with PAM_ESTABLISH_CRED at least once, which resolves a problem

diff --git a/clientloop.c b/clientloop.c
index 538644c201dbfd48637bff6766abd7e3cb6756dd..b57fda042a015a00ba4ba9c332b76e3eba11f8b9 100644 (file)
--- a/clientloop.c
+++ b/clientloop.c
@@ -1,4 +1,4 @@
-/* $OpenBSD: clientloop.c,v 1.180 2007/08/07 07:32:53 djm Exp $ */
+/* $OpenBSD: clientloop.c,v 1.181 2007/08/15 08:14:46 markus Exp $ */
 /*
  * Author: Tatu Ylonen <ylo@cs.hut.fi>
  * Copyright (c) 1995 Tatu Ylonen <ylo@cs.hut.fi>, Espoo, Finland
@@ -290,19 +290,29 @@ client_x11_get_proto(const char *display, const char *xauth_path,
                                        generated = 1;
                        }
                }
-               snprintf(cmd, sizeof(cmd),
-                   "%s %s%s list %s 2>" _PATH_DEVNULL,
-                   xauth_path,
-                   generated ? "-f " : "" ,
-                   generated ? xauthfile : "",
-                   display);
-               debug2("x11_get_proto: %s", cmd);
-               f = popen(cmd, "r");
-               if (f && fgets(line, sizeof(line), f) &&
-                   sscanf(line, "%*s %511s %511s", proto, data) == 2)
-                       got_data = 1;
-               if (f)
-                       pclose(f);
+
+               /*
+                * When in untrusted mode, we read the cookie only if it was
+                * successfully generated as an untrusted one in the step
+                * above.
+                */
+               if (trusted || generated) {
+                       snprintf(cmd, sizeof(cmd),
+                           "%s %s%s list %s 2>" _PATH_DEVNULL,
+                           xauth_path,
+                           generated ? "-f " : "" ,
+                           generated ? xauthfile : "",
+                           display);
+                       debug2("x11_get_proto: %s", cmd);
+                       f = popen(cmd, "r");
+                       if (f && fgets(line, sizeof(line), f) &&
+                           sscanf(line, "%*s %511s %511s", proto, data) == 2)
+                               got_data = 1;
+                       if (f)
+                               pclose(f);
+               } else
+                       error("Warning: untrusted X11 forwarding setup failed: "
+                           "xauth key data not generated");
        }
 
        if (do_unlink) {