Make name conversion more robust to failure

NTLMSSP does not have export_name functions yet, this was causing
gss_export_composite_name() to fail with a GSS_S_UNAVAILABLE error.

This should be ignored, however it wasn't and on top of that the output
structure was initialized but held pointers to memory freed at exit (due to the
error).

Make the function not failed if a mechanism do not have composite export
function, but if it does make sure the output is not littered with invalid
pointers.

Signed-off-by: Simo Sorce <simo@redhat.com>
Reviewed-by: Günther Deschner <gdeschner@redhat.com>

1 files changed, 14 insertions, 10 deletions

diff --git a/proxy/src/gp_conv.c b/proxy/src/gp_conv.c
index a9f9669..f05559f 100644
--- a/proxy/src/gp_conv.c
+++ b/proxy/src/gp_conv.c
@@ -356,7 +356,7 @@ done:
     return ret;
 }
 
-uint32_t gp_conv_name_to_gssx(uint32_t *min, gss_name_t in, gssx_name *out)
+uint32_t gp_conv_name_to_gssx(uint32_t *min, gss_name_t in, gssx_name *_out)
 {
     uint32_t ret_maj;
     uint32_t ret_min;
@@ -364,6 +364,7 @@ uint32_t gp_conv_name_to_gssx(uint32_t *min, gss_name_t in, gssx_name *out)
     gss_OID name_type;
     gss_buffer_desc exported_name = GSS_C_EMPTY_BUFFER;
     gss_buffer_desc exported_composite_name = GSS_C_EMPTY_BUFFER;
+    gssx_name out = { .display_name.octet_string_len = 0 };
     int ret;
 
     ret_maj = gss_display_name(&ret_min, in, &name_buffer, &name_type);
@@ -371,13 +372,13 @@ uint32_t gp_conv_name_to_gssx(uint32_t *min, gss_name_t in, gssx_name *out)
         goto done;
     }
 
-    ret = gp_conv_buffer_to_gssx(&name_buffer, &out->display_name);
+    ret = gp_conv_buffer_to_gssx(&name_buffer, &out.display_name);
     if (ret) {
         ret_maj = GSS_S_FAILURE;
         ret_min = ret;
         goto done;
     }
-    ret = gp_conv_oid_to_gssx(name_type, &out->name_type);
+    ret = gp_conv_oid_to_gssx(name_type, &out.name_type);
     if (ret) {
         ret_maj = GSS_S_FAILURE;
         ret_min = ret;
@@ -386,7 +387,7 @@ uint32_t gp_conv_name_to_gssx(uint32_t *min, gss_name_t in, gssx_name *out)
 
     ret_maj = gss_export_name(&ret_min, in, &exported_name);
     if (ret_maj == 0) {
-        ret = gp_conv_buffer_to_gssx(&exported_name, &out->exported_name);
+        ret = gp_conv_buffer_to_gssx(&exported_name, &out.exported_name);
         if (ret) {
             ret_maj = GSS_S_FAILURE;
             ret_min = ret;
@@ -403,7 +404,7 @@ uint32_t gp_conv_name_to_gssx(uint32_t *min, gss_name_t in, gssx_name *out)
 
     ret_maj = gss_export_name_composite(&ret_min, in, &exported_composite_name);
     if (ret_maj == 0) {
-        ret = gp_conv_buffer_to_gssx(&exported_composite_name, &out->exported_composite_name);
+        ret = gp_conv_buffer_to_gssx(&exported_composite_name, &out.exported_composite_name);
         if (ret) {
             ret_maj = GSS_S_FAILURE;
             ret_min = ret;
@@ -413,7 +414,8 @@ uint32_t gp_conv_name_to_gssx(uint32_t *min, gss_name_t in, gssx_name *out)
         /* In case the error is GSS_S_NAME_NOT_MN the name was not
          * canonicalized but that is ok we simply do not export the name
          * in this case */
-        if (ret_maj != GSS_S_NAME_NOT_MN) {
+        if (ret_maj != GSS_S_NAME_NOT_MN &&
+            ret_maj != GSS_S_UNAVAILABLE) {
             goto done;
         }
     }
@@ -428,10 +430,12 @@ done:
     gss_release_buffer(&ret_min, &exported_name);
     gss_release_buffer(&ret_min, &exported_composite_name);
     if (ret_maj) {
-        xdr_free((xdrproc_t)xdr_gssx_buffer, (char *)&out->display_name);
-        xdr_free((xdrproc_t)xdr_gssx_OID, (char *)&out->name_type);
-        xdr_free((xdrproc_t)xdr_gssx_buffer, (char *)&out->exported_name);
-        xdr_free((xdrproc_t)xdr_gssx_buffer, (char *)&out->exported_composite_name);
+        xdr_free((xdrproc_t)xdr_gssx_buffer, (char *)&out.display_name);
+        xdr_free((xdrproc_t)xdr_gssx_OID, (char *)&out.name_type);
+        xdr_free((xdrproc_t)xdr_gssx_buffer, (char *)&out.exported_name);
+        xdr_free((xdrproc_t)xdr_gssx_buffer, (char *)&out.exported_composite_name);
+    } else {
+        *_out = out;
     }
     return ret_maj;
 }