s3:winbindd: use wb_sids2xids instead of wb_sid2gid in winbindd_sid_to_gid

The main purpose of the change is to hand the sid into the
idmap backend and handle responsiblity for handling the
sid-type correctly to the idmap backend instead of failing
directly when the sid is not of group type.

Hence backends like rid who are sid-type agnostic, can
return gids also for sids of other types. This is an important
fix to make sid_to_gid behave the consistently with and without
the presence of cache entries.

We need to additionally filter the result for id type GID
or more general (BOTH) to keep the behaviour.

This is a step towards using only one codepath to id_mapping.

Signed-off-by: Michael Adam <obnox@samba.org>
Reviewed-by: Stefan Metzmacher <metze@samba.org>

1 files changed, 16 insertions, 2 deletions

diff --git a/source3/winbindd/winbindd_sid_to_gid.c b/source3/winbindd/winbindd_sid_to_gid.c
index df44ed8d6b..46ca903cd3 100644
--- a/source3/winbindd/winbindd_sid_to_gid.c
+++ b/source3/winbindd/winbindd_sid_to_gid.c
@@ -54,7 +54,7 @@ struct tevent_req *winbindd_sid_to_gid_send(TALLOC_CTX *mem_ctx,
 		return tevent_req_post(req, ev);
 	}
 
-	subreq = wb_sid2gid_send(state, ev, &state->sid);
+	subreq = wb_sids2xids_send(state, ev, &state->sid, 1);
 	if (tevent_req_nomem(subreq, req)) {
 		return tevent_req_post(req, ev);
 	}
@@ -69,12 +69,26 @@ static void winbindd_sid_to_gid_done(struct tevent_req *subreq)
 	struct winbindd_sid_to_gid_state *state = tevent_req_data(
 		req, struct winbindd_sid_to_gid_state);
 	NTSTATUS status;
+	struct unixid xid;
 
-	status = wb_sid2gid_recv(subreq, &state->gid);
+	status = wb_sids2xids_recv(subreq, &xid);
 	TALLOC_FREE(subreq);
 	if (tevent_req_nterror(req, status)) {
 		return;
 	}
+
+	/*
+	 * We are filtering further down in sids2xids, but that filtering
+	 * depends on the actual type of the sid handed in (as determined
+	 * by lookupsids). Here we need to filter for the type of object
+	 * actually requested, in this case gid.
+	 */
+	if (!(xid.type == ID_TYPE_GID || xid.type == ID_TYPE_BOTH)) {
+		tevent_req_nterror(req, NT_STATUS_NONE_MAPPED);
+		return;
+	}
+
+	state->gid = (gid_t)xid.id;
 	tevent_req_done(req);
 }