Added ability to remove id mappings in wbinfo and libwbclient.

The idmap_tdb backend already provides an interface to remove existing id
mappings.  This commit plumbs that ability up through, winbindd, libwbclient,
and wbinfo.

Added new winbindd command:
        WINBINDD_REMOVE_MAPPING
Added new libwbclient interfaces:
        wbcRemoveUidMapping() and wbcRemoveGidMapping()
Added new wbinfo options:
        --remove-uid-mapping
        --remove-gid-mapping

Increased libwbclient version to 0.2
Increased winbind interface version to 20

6 files changed, 141 insertions, 2 deletions

diff --git a/source3/winbindd/idmap.c b/source3/winbindd/idmap.c
index cfc5597f42..054df9be05 100644
--- a/source3/winbindd/idmap.c
+++ b/source3/winbindd/idmap.c
@@ -788,3 +788,20 @@ NTSTATUS idmap_set_mapping(const struct id_map *map)
 
 	return dom->methods->set_mapping(dom, map);
 }
+
+NTSTATUS idmap_remove_mapping(const struct id_map *map)
+{
+	struct idmap_domain *dom;
+
+	dom = idmap_find_domain(NULL);
+	if (dom == NULL) {
+		DEBUG(3, ("no default domain, no place to write\n"));
+		return NT_STATUS_ACCESS_DENIED;
+	}
+	if (dom->methods->remove_mapping == NULL) {
+		DEBUG(3, ("default domain not writable\n"));
+		return NT_STATUS_MEDIA_WRITE_PROTECTED;
+	}
+
+	return dom->methods->remove_mapping(dom, map);
+}
diff --git a/source3/winbindd/idmap_tdb.c b/source3/winbindd/idmap_tdb.c
index f9d3a9fbff..7c4de5f6fb 100644
--- a/source3/winbindd/idmap_tdb.c
+++ b/source3/winbindd/idmap_tdb.c
@@ -875,8 +875,13 @@ static NTSTATUS idmap_tdb_set_mapping(struct idmap_domain *dom, const struct id_
 	ksid = string_term_tdb_data(ksidstr);
 
 	/* *DELETE* previous mappings if any.
-	 * This is done both SID and [U|G]ID passed in */
-	
+	 * This is done for both the SID and [U|G]ID passed in */
+
+	/* NOTE: We should lock both the ksid and kid records here, before
+	 * making modifications.  However, because tdb_chainlock() is a
+	 * blocking call we could create an unrecoverable deadlock, so for now
+	 * we only lock the ksid record. */
+
 	/* Lock the record for this SID. */
 	if (tdb_chainlock(ctx->tdb, ksid) != 0) {
 		DEBUG(10,("Failed to lock record %s. Error %s\n",
@@ -981,6 +986,11 @@ static NTSTATUS idmap_tdb_remove_mapping(struct idmap_domain *dom, const struct
 	ksid = string_term_tdb_data(ksidstr);
 	kid = string_term_tdb_data(kidstr);
 
+	/* NOTE: We should lock both the ksid and kid records here, before
+	 * making modifications.  However, because tdb_chainlock() is a
+	 * blocking call we could create an unrecoverable deadlock, so for now
+	 * we only lock the ksid record. */
+
 	/* Lock the record for this SID. */
 	if (tdb_chainlock(ctx->tdb, ksid) != 0) {
 		DEBUG(10,("Failed to lock record %s. Error %s\n",
diff --git a/source3/winbindd/winbindd.c b/source3/winbindd/winbindd.c
index ce1a1fe52f..9e8a5a613e 100644
--- a/source3/winbindd/winbindd.c
+++ b/source3/winbindd/winbindd.c
@@ -343,6 +343,7 @@ static struct winbindd_dispatch_table {
 	{ WINBINDD_ALLOCATE_UID, winbindd_allocate_uid, "ALLOCATE_UID" },
 	{ WINBINDD_ALLOCATE_GID, winbindd_allocate_gid, "ALLOCATE_GID" },
 	{ WINBINDD_SET_MAPPING, winbindd_set_mapping, "SET_MAPPING" },
+	{ WINBINDD_REMOVE_MAPPING, winbindd_remove_mapping, "REMOVE_MAPPING" },
 	{ WINBINDD_SET_HWM, winbindd_set_hwm, "SET_HWMS" },
 
 	/* Miscellaneous */
diff --git a/source3/winbindd/winbindd_idmap.c b/source3/winbindd/winbindd_idmap.c
index d8c67dc21c..94a8c78a85 100644
--- a/source3/winbindd/winbindd_idmap.c
+++ b/source3/winbindd/winbindd_idmap.c
@@ -111,6 +111,65 @@ enum winbindd_result winbindd_dual_set_mapping(struct winbindd_domain *domain,
 	return NT_STATUS_IS_OK(result) ? WINBINDD_OK : WINBINDD_ERROR;
 }
 
+static void winbindd_remove_mapping_recv(TALLOC_CTX *mem_ctx, bool success,
+				   struct winbindd_response *response,
+				   void *c, void *private_data)
+{
+	void (*cont)(void *priv, bool succ) = (void (*)(void *, bool))c;
+
+	if (!success) {
+		DEBUG(5, ("Could not trigger idmap_remove_mapping\n"));
+		cont(private_data, False);
+		return;
+	}
+
+	if (response->result != WINBINDD_OK) {
+		DEBUG(5, ("idmap_remove_mapping returned an error\n"));
+		cont(private_data, False);
+		return;
+	}
+
+	cont(private_data, True);
+}
+
+void winbindd_remove_mapping_async(TALLOC_CTX *mem_ctx,
+			     const struct id_map *map,
+			     void (*cont)(void *private_data, bool success),
+			     void *private_data)
+{
+	struct winbindd_request request;
+	ZERO_STRUCT(request);
+	request.cmd = WINBINDD_DUAL_REMOVE_MAPPING;
+	request.data.dual_idmapset.id = map->xid.id;
+	request.data.dual_idmapset.type = map->xid.type;
+	sid_to_fstring(request.data.dual_idmapset.sid, map->sid);
+
+	do_async(mem_ctx, idmap_child(), &request, winbindd_remove_mapping_recv,
+		 (void *)cont, private_data);
+}
+
+enum winbindd_result winbindd_dual_remove_mapping(
+					    struct winbindd_domain *domain,
+					    struct winbindd_cli_state *state)
+{
+	struct id_map map;
+	DOM_SID sid;
+	NTSTATUS result;
+
+	DEBUG(3, ("[%5lu]: dual_idmapremove\n", (unsigned long)state->pid));
+
+	if (!string_to_sid(&sid, state->request.data.dual_idmapset.sid))
+		return WINBINDD_ERROR;
+
+	map.sid = &sid;
+	map.xid.id = state->request.data.dual_idmapset.id;
+	map.xid.type = state->request.data.dual_idmapset.type;
+	map.status = ID_MAPPED;
+
+	result = idmap_remove_mapping(&map);
+	return NT_STATUS_IS_OK(result) ? WINBINDD_OK : WINBINDD_ERROR;
+}
+
 static void winbindd_set_hwm_recv(TALLOC_CTX *mem_ctx, bool success,
 				   struct winbindd_response *response,
 				   void *c, void *private_data)
@@ -486,6 +545,10 @@ static const struct winbindd_child_dispatch_table idmap_dispatch_table[] = {
 		.struct_cmd	= WINBINDD_DUAL_SET_MAPPING,
 		.struct_fn	= winbindd_dual_set_mapping,
 	},{
+		.name		= "DUAL_REMOVE_MAPPING",
+		.struct_cmd	= WINBINDD_DUAL_REMOVE_MAPPING,
+		.struct_fn	= winbindd_dual_remove_mapping,
+	},{
 		.name		= "DUAL_SET_HWMS",
 		.struct_cmd	= WINBINDD_DUAL_SET_HWM,
 		.struct_fn	= winbindd_dual_set_hwm,
diff --git a/source3/winbindd/winbindd_proto.h b/source3/winbindd/winbindd_proto.h
index 65ad47dd03..4f3d10f57f 100644
--- a/source3/winbindd/winbindd_proto.h
+++ b/source3/winbindd/winbindd_proto.h
@@ -353,6 +353,11 @@ void winbindd_set_mapping_async(TALLOC_CTX *mem_ctx, const struct id_map *map,
 			     void *private_data);
 enum winbindd_result winbindd_dual_set_mapping(struct winbindd_domain *domain,
 					    struct winbindd_cli_state *state);
+void winbindd_remove_mapping_async(TALLOC_CTX *mem_ctx, const struct id_map *map,
+			     void (*cont)(void *private_data, bool success),
+			     void *private_data);
+enum winbindd_result winbindd_dual_remove_mapping(struct winbindd_domain *domain,
+					    struct winbindd_cli_state *state);
 void winbindd_set_hwm_async(TALLOC_CTX *mem_ctx, const struct unixid *xid,
 			     void (*cont)(void *private_data, bool success),
 			     void *private_data);
@@ -505,6 +510,7 @@ void winbindd_sid_to_uid(struct winbindd_cli_state *state);
 void winbindd_sid_to_gid(struct winbindd_cli_state *state);
 void winbindd_sids_to_unixids(struct winbindd_cli_state *state);
 void winbindd_set_mapping(struct winbindd_cli_state *state);
+void winbindd_remove_mapping(struct winbindd_cli_state *state);
 void winbindd_set_hwm(struct winbindd_cli_state *state);
 void winbindd_uid_to_sid(struct winbindd_cli_state *state);
 void winbindd_gid_to_sid(struct winbindd_cli_state *state);
diff --git a/source3/winbindd/winbindd_sid.c b/source3/winbindd/winbindd_sid.c
index 274786fa63..d8bd863037 100644
--- a/source3/winbindd/winbindd_sid.c
+++ b/source3/winbindd/winbindd_sid.c
@@ -415,6 +415,48 @@ void winbindd_set_mapping(struct winbindd_cli_state *state)
 			set_mapping_recv, state);
 }
 
+static void remove_mapping_recv(void *private_data, bool success)
+{
+	struct winbindd_cli_state *state =
+		talloc_get_type_abort(private_data, struct winbindd_cli_state);
+
+	if (!success) {
+		DEBUG(5, ("Could not remove sid mapping\n"));
+		request_error(state);
+		return;
+	}
+
+	request_ok(state);
+}
+
+void winbindd_remove_mapping(struct winbindd_cli_state *state)
+{
+	struct id_map map;
+	DOM_SID sid;
+
+	DEBUG(3, ("[%5lu]: remove id map\n", (unsigned long)state->pid));
+
+	if ( ! state->privileged) {
+		DEBUG(0, ("Only root is allowed to remove mappings!\n"));
+		request_error(state);
+		return;
+	}
+
+	if (!string_to_sid(&sid, state->request.data.dual_idmapset.sid)) {
+		DEBUG(1, ("Could not get convert sid %s from string\n",
+			  state->request.data.sid));
+		request_error(state);
+		return;
+	}
+
+	map.sid = &sid;
+	map.xid.id = state->request.data.dual_idmapset.id;
+	map.xid.type = state->request.data.dual_idmapset.type;
+
+	winbindd_remove_mapping_async(state->mem_ctx, &map,
+			remove_mapping_recv, state);
+}
+
 static void set_hwm_recv(void *private_data, bool success)
 {
 	struct winbindd_cli_state *state =