[krbdev.mit.edu #5802] libgssapi mechglue doesn't always store delegated credentials

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>Submitter-Id:	net
>Originator:	
>Organization:
Nalin
>Confidential:	no
>Synopsis:	libgssapi mechglue doesn't always store delegated credentials
>Severity:	non-critical
>Priority:	medium
>Category:	krb5-libs
>Class:		sw-bug
>Release:	1.6.2
>Environment:
	
System: Linux blade.boston.redhat.com 2.6.23-0.211.rc8.git2.fc8 #1 SMP Thu Sep 27 18:21:00 EDT 2007 x86_64 x86_64 x86_64 GNU/Linux
Architecture: x86_64

>Description:
	The mechglue wrapper for gss_init_sec_context doesn't appear to be
	handling the ret_flags parameter correctly.
	* If the caller passes in NULL, the mechanism-specific function can't
	  store its own returned flags, so the wrapper can't dependably
	  be expected to store delegated credentials.
	* The wrapper also appears to be checking for the bit in ret_flags
	  (which is a pointer to a bitfield) incorrectly.
>How-To-Repeat:
	Using elinks to perform negotiate authentication to a patched
	mod_auth_kerb (both found in RHEL, if that helps), this happens
	pretty reliably.
>Fix:
	Proposed patch:

Index: src/lib/gssapi/mechglue/g_accept_sec_context.c
===================================================================
--- src/lib/gssapi/mechglue/g_accept_sec_context.c	(revision 20038)
+++ src/lib/gssapi/mechglue/g_accept_sec_context.c	(working copy)
@@ -112,6 +112,7 @@
 
 {
     OM_uint32		status, temp_status, temp_minor_status;
+    OM_uint32		temp_ret_flags = 0;
     gss_union_ctx_id_t	union_ctx_id;
     gss_union_cred_t	union_cred;
     gss_cred_id_t	input_cred_handle = GSS_C_NO_CREDENTIAL;
@@ -202,7 +203,7 @@
 						  &internal_name,
 						  mech_type,
 						  output_token,
-						  ret_flags,
+						  &temp_ret_flags,
 						  time_rec,
 					d_cred ? &tmp_d_cred : NULL);
 
@@ -248,7 +249,7 @@
 	    }
 
 	    /* Ensure we're returning correct creds format */
-	    if ((ret_flags && GSS_C_DELEG_FLAG) &&
+	    if ((temp_ret_flags & GSS_C_DELEG_FLAG) &&
 		tmp_d_cred != GSS_C_NO_CREDENTIAL) {
 		gss_union_cred_t d_u_cred = NULL;
 
@@ -335,6 +336,8 @@
 	    if (src_name == NULL && tmp_src_name != NULL)
 		(void) gss_release_name(&temp_minor_status,
 					&tmp_src_name);
+	    if (ret_flags != NULL)
+		*ret_flags = temp_ret_flags;
 	    return	(status);
     } else {