[PATCH 1/3] Don't attempt to use non-existant default credentials cache

[Kevin Coffman]

From: Lukas Hejtmanek <xhejtman at ics.muni.cz>

gssd_setup_krb5_user_gss_ccache must return an error if no usable cache is
found. Trying to use invalid default cache and continue is not good idea at all.

Signed-off-by: Lukas Hejtmanek <xhejtman at ics.muni.cz>
Signed-off-by: Kevin Coffman <kwc at citi.umich.edu>
---

 utils/gssd/gssd_proc.c |    5 ++---
 utils/gssd/krb5_util.c |    9 +++++----
 utils/gssd/krb5_util.h |    2 +-
 3 files changed, 8 insertions(+), 8 deletions(-)

diff --git a/utils/gssd/gssd_proc.c b/utils/gssd/gssd_proc.c
index be6f440..a145081 100644
--- a/utils/gssd/gssd_proc.c
+++ b/utils/gssd/gssd_proc.c
@@ -703,9 +703,8 @@ handle_krb5_upcall(struct clnt_info *clp)
 	if (uid != 0 || (uid == 0 && root_uses_machine_creds == 0)) {
 		/* Tell krb5 gss which credentials cache to use */
 		for (dirname = ccachesearch; *dirname != NULL; dirname++) {
-			gssd_setup_krb5_user_gss_ccache(uid, clp->servername, *dirname);
-
-			create_resp = create_auth_rpc_client(clp, &rpc_clnt, &auth, uid,
+			if (gssd_setup_krb5_user_gss_ccache(uid, clp->servername, *dirname) == 0)
+				create_resp = create_auth_rpc_client(clp, &rpc_clnt, &auth, uid,
 							     AUTHTYPE_KRB5);
 			if (create_resp == 0)
 				break;
diff --git a/utils/gssd/krb5_util.c b/utils/gssd/krb5_util.c
index 512c1cf..4a4d10b 100644
--- a/utils/gssd/krb5_util.c
+++ b/utils/gssd/krb5_util.c
@@ -894,9 +894,10 @@ out:
  * do the best we can.
  *
  * Returns:
- *	void
+ *	0 => a ccache was found
+ *	1 => no ccache was found
  */
-void
+int
 gssd_setup_krb5_user_gss_ccache(uid_t uid, char *servername, char *dirname)
 {
 	char			buf[MAX_NETOBJ_SZ];
@@ -910,11 +911,11 @@ gssd_setup_krb5_user_gss_ccache(uid_t uid, char *servername, char *dirname)
 		free(d);
 	}
 	else
-		snprintf(buf, sizeof(buf), "FILE:%s/%s%u",
-			dirname, GSSD_DEFAULT_CRED_PREFIX, uid);
+		return 1;
 	printerr(2, "using %s as credentials cache for client with "
 		    "uid %u for server %s\n", buf, uid, servername);
 	gssd_set_krb5_ccache_name(buf);
+	return 0;
 }
 
 /*
diff --git a/utils/gssd/krb5_util.h b/utils/gssd/krb5_util.h
index 431fdaf..addae1c 100644
--- a/utils/gssd/krb5_util.h
+++ b/utils/gssd/krb5_util.h
@@ -17,7 +17,7 @@ struct gssd_k5_kt_princ {
 };
 
 
-void gssd_setup_krb5_user_gss_ccache(uid_t uid, char *servername,
+int gssd_setup_krb5_user_gss_ccache(uid_t uid, char *servername,
 				     char *dirname);
 int  gssd_get_krb5_machine_cred_list(char ***list);
 void gssd_free_krb5_machine_cred_list(char **list);