krb5 commit [krb5-1.15]: Always honor desired_name in gss_add_cred()

[Greg Hudson]

https://github.com/krb5/krb5/commit/0ab749b38930d43b4640b7b2e9448079510fd4a5
commit 0ab749b38930d43b4640b7b2e9448079510fd4a5
Author: Greg Hudson <ghudson at mit.edu>
Date:   Fri Sep 14 20:35:50 2018 -0400

    Always honor desired_name in gss_add_cred()
    
    Remove the conditionalization around the desired_name processing in
    gss_add_cred_from(), so that we always honor the requested name.
    
    (cherry picked from commit 6d4eb6eb473c93f0db05409195448364382760a9)
    
    ticket: 8737
    version_fixed: 1.15.4

 src/lib/gssapi/mechglue/g_acquire_cred.c |   28 +++++++++++++---------------
 src/tests/gssapi/t_add_cred.c            |   10 ++++++++++
 2 files changed, 23 insertions(+), 15 deletions(-)

diff --git a/src/lib/gssapi/mechglue/g_acquire_cred.c b/src/lib/gssapi/mechglue/g_acquire_cred.c
index 5e82495..e7b3ed6 100644
--- a/src/lib/gssapi/mechglue/g_acquire_cred.c
+++ b/src/lib/gssapi/mechglue/g_acquire_cred.c
@@ -408,22 +408,20 @@ gss_add_cred_from(minor_status, input_cred_handle,
 	    return (GSS_S_DUPLICATE_ELEMENT);
     }
 
-    /* for default credentials we will use GSS_C_NO_NAME */
-    if (input_cred_handle != GSS_C_NO_CREDENTIAL ||
-        cred_store != GSS_C_NO_CRED_STORE) {
-	/* may need to create a mechanism specific name */
-	if (desired_name) {
-	    union_name = (gss_union_name_t)desired_name;
-	    if (union_name->mech_type &&
-		g_OID_equal(union_name->mech_type, selected_mech))
-		internal_name = union_name->mech_name;
-	    else {
-		if (gssint_import_internal_name(minor_status, selected_mech,
-						union_name, &allocated_name) !=
-		    GSS_S_COMPLETE)
-		    return (GSS_S_BAD_NAME);
-		internal_name = allocated_name;
+    /* We may need to create a mechanism specific name. */
+    if (desired_name != GSS_C_NO_NAME) {
+	union_name = (gss_union_name_t)desired_name;
+	if (union_name->mech_type &&
+	    g_OID_equal(union_name->mech_type, selected_mech)) {
+	    internal_name = union_name->mech_name;
+	} else {
+	    if (gssint_import_internal_name(minor_status, selected_mech,
+					    union_name, &allocated_name) !=
+		GSS_S_COMPLETE) {
+		status = GSS_S_BAD_NAME;
+		goto errout;
 	    }
+	    internal_name = allocated_name;
 	}
     }
 
diff --git a/src/tests/gssapi/t_add_cred.c b/src/tests/gssapi/t_add_cred.c
index d59fde9..1407e67 100644
--- a/src/tests/gssapi/t_add_cred.c
+++ b/src/tests/gssapi/t_add_cred.c
@@ -48,6 +48,7 @@ main()
     OM_uint32 minor, major;
     gss_cred_id_t cred1;
     gss_cred_usage_t usage;
+    gss_name_t name;
 
     /* Check that we get the expected error if we pass neither an input nor an
      * output cred handle. */
@@ -56,6 +57,15 @@ main()
                          GSS_C_INDEFINITE, NULL, NULL, NULL, NULL);
     assert(major == (GSS_S_CALL_INACCESSIBLE_WRITE | GSS_S_NO_CRED));
 
+    /* Regression test for #8737: make sure that desired_name is honored when
+     * creating a credential by passing in a non-matching name. */
+    name = import_name("p:does/not/match at WRONG_REALM");
+    major = gss_add_cred(&minor, GSS_C_NO_CREDENTIAL, name, &mech_krb5,
+                         GSS_C_INITIATE, GSS_C_INDEFINITE, GSS_C_INDEFINITE,
+                         &cred1, NULL, NULL, NULL);
+    assert(major == GSS_S_CRED_UNAVAIL);
+    gss_release_name(&minor, &name);
+
     /* Create cred1 with a krb5 initiator cred by passing an output handle but
      * no input handle. */
     major = gss_add_cred(&minor, GSS_C_NO_CREDENTIAL, GSS_C_NO_NAME,