- (djm) OpenBSD CVS Sync

   - djm@cvs.openbsd.org 2005/08/30 22:08:05
     [gss-serv.c sshconnect2.c]
     destroy credentials if krb5_kuserok() call fails. Stops credentials being
     delegated to users who are not authorised for GSSAPIAuthentication when
     GSSAPIDeletegateCredentials=yes and another authentication mechanism
     succeeds; bz#1073 reported by paul.moore AT centrify.com, fix by
     simon AT sxw.org.uk, tested todd@ biorn@ jakob@; ok deraadt@

1 files changed, 13 insertions, 2 deletions

diff --git a/gss-serv.c b/gss-serv.c
index e191eb5a0..117130459 100644
--- a/gss-serv.c
+++ b/gss-serv.c
@@ -1,4 +1,4 @@
-/*      $OpenBSD: gss-serv.c,v 1.7 2005/07/17 07:17:55 djm Exp $        */
+/*      $OpenBSD: gss-serv.c,v 1.8 2005/08/30 22:08:05 djm Exp $        */
 
 /*
  * Copyright (c) 2001-2003 Simon Wilkinson. All rights reserved.
@@ -275,13 +275,24 @@ ssh_gssapi_do_child(char ***envp, u_int *envsizep)
 int
 ssh_gssapi_userok(char *user)
 {
+        OM_uint32 lmin;
+
         if (gssapi_client.exportedname.length == 0 ||
             gssapi_client.exportedname.value == NULL) {
                 debug("No suitable client data");
                 return 0;
         }
         if (gssapi_client.mech && gssapi_client.mech->userok)
-                return ((*gssapi_client.mech->userok)(&gssapi_client, user));
+                if ((*gssapi_client.mech->userok)(&gssapi_client, user))
+                        return 1;
+                else {
+                        /* Destroy delegated credentials if userok fails */
+                        gss_release_buffer(&lmin, &gssapi_client.displayname);
+                        gss_release_buffer(&lmin, &gssapi_client.exportedname);
+                        gss_release_cred(&lmin, &gssapi_client.creds);
+                        memset(&gssapi_client, 0, sizeof(ssh_gssapi_client));
+                        return 0;
+                }
         else
                 debug("ssh_gssapi_userok: Unknown GSSAPI mechanism");
         return (0);