r23323: merged ldb changes from 3.0.26

(This used to be commit 7c9a5c2a3f012a06e9550dc0de7df460c2fd943b)

4 files changed, 192 insertions, 134 deletions

diff --git a/source3/groupdb/mapping.c b/source3/groupdb/mapping.c
index 514b44f5b4..9ead1c6317 100644
--- a/source3/groupdb/mapping.c
+++ b/source3/groupdb/mapping.c
@@ -24,6 +24,37 @@
 #include "includes.h"
 #include "groupdb/mapping.h"
 
+static const struct mapping_backend *backend;
+
+/*
+  initialise a group mapping backend
+ */
+static BOOL init_group_mapping(void)
+{
+	const char *backend_string;
+
+	if (backend != NULL) {
+		/* already initialised */
+		return True;
+	}
+	
+	/* default to using the ldb backend. This parameter should
+	   disappear in future versions of Samba3, but for now it
+	   provides a safety net in case any major problems are
+	   discovered with ldb after the release */	   
+	backend_string = lp_parm_const_string(-1, "groupdb", "backend", "ldb");
+
+	if (strcmp(backend_string, "ldb") == 0) {
+		backend = groupdb_ldb_init();
+	} else if (strcmp(backend_string, "tdb") == 0) {
+		backend = groupdb_tdb_init();
+	} else {
+		DEBUG(0,("Unknown groupdb backend '%s'\n", backend_string));
+		smb_panic("Unknown groupdb backend\n");
+	}
+	return backend != NULL;
+}
+
 /****************************************************************************
 initialise first time the mapping list
 ****************************************************************************/
@@ -58,7 +89,7 @@ static NTSTATUS alias_memberships(const DOM_SID *members, size_t num_members,
 	*sids = NULL;
 
 	for (i=0; i<num_members; i++) {
-		NTSTATUS status = one_alias_membership(&members[i], sids, num);
+		NTSTATUS status = backend->one_alias_membership(&members[i], sids, num);
 		if (!NT_STATUS_IS_OK(status))
 			return status;
 	}
@@ -304,42 +335,66 @@ int smb_delete_user_group(const char *unix_group, const char *unix_user)
 NTSTATUS pdb_default_getgrsid(struct pdb_methods *methods, GROUP_MAP *map,
 				 DOM_SID sid)
 {
-	return get_group_map_from_sid(sid, map) ?
+	if (!init_group_mapping()) {
+		DEBUG(0,("failed to initialize group mapping\n"));
+		return NT_STATUS_UNSUCCESSFUL;
+	}
+	return backend->get_group_map_from_sid(sid, map) ?
 		NT_STATUS_OK : NT_STATUS_UNSUCCESSFUL;
 }
 
 NTSTATUS pdb_default_getgrgid(struct pdb_methods *methods, GROUP_MAP *map,
 				 gid_t gid)
 {
-	return get_group_map_from_gid(gid, map) ?
+	if (!init_group_mapping()) {
+		DEBUG(0,("failed to initialize group mapping\n"));
+		return NT_STATUS_UNSUCCESSFUL;
+	}
+	return backend->get_group_map_from_gid(gid, map) ?
 		NT_STATUS_OK : NT_STATUS_UNSUCCESSFUL;
 }
 
 NTSTATUS pdb_default_getgrnam(struct pdb_methods *methods, GROUP_MAP *map,
 				 const char *name)
 {
-	return get_group_map_from_ntname(name, map) ?
+	if (!init_group_mapping()) {
+		DEBUG(0,("failed to initialize group mapping\n"));
+		return NT_STATUS_UNSUCCESSFUL;
+	}
+	return backend->get_group_map_from_ntname(name, map) ?
 		NT_STATUS_OK : NT_STATUS_UNSUCCESSFUL;
 }
 
 NTSTATUS pdb_default_add_group_mapping_entry(struct pdb_methods *methods,
 						GROUP_MAP *map)
 {
-	return add_mapping_entry(map, TDB_INSERT) ?
+	if (!init_group_mapping()) {
+		DEBUG(0,("failed to initialize group mapping\n"));
+		return NT_STATUS_UNSUCCESSFUL;
+	}
+	return backend->add_mapping_entry(map, TDB_INSERT) ?
 		NT_STATUS_OK : NT_STATUS_UNSUCCESSFUL;
 }
 
 NTSTATUS pdb_default_update_group_mapping_entry(struct pdb_methods *methods,
 						   GROUP_MAP *map)
 {
-	return add_mapping_entry(map, TDB_REPLACE) ?
+	if (!init_group_mapping()) {
+		DEBUG(0,("failed to initialize group mapping\n"));
+		return NT_STATUS_UNSUCCESSFUL;
+	}
+	return backend->add_mapping_entry(map, TDB_REPLACE) ?
 		NT_STATUS_OK : NT_STATUS_UNSUCCESSFUL;
 }
 
 NTSTATUS pdb_default_delete_group_mapping_entry(struct pdb_methods *methods,
 						   DOM_SID sid)
 {
-	return group_map_remove(&sid) ?
+	if (!init_group_mapping()) {
+		DEBUG(0,("failed to initialize group mapping\n"));
+		return NT_STATUS_UNSUCCESSFUL;
+	}
+	return backend->group_map_remove(&sid) ?
 		NT_STATUS_OK : NT_STATUS_UNSUCCESSFUL;
 }
 
@@ -348,7 +403,11 @@ NTSTATUS pdb_default_enum_group_mapping(struct pdb_methods *methods,
 					   GROUP_MAP **pp_rmap, size_t *p_num_entries,
 					   BOOL unix_only)
 {
-	return enum_group_mapping(sid, sid_name_use, pp_rmap, p_num_entries, unix_only) ?
+	if (!init_group_mapping()) {
+		DEBUG(0,("failed to initialize group mapping\n"));
+		return NT_STATUS_UNSUCCESSFUL;
+	}
+	return backend->enum_group_mapping(sid, sid_name_use, pp_rmap, p_num_entries, unix_only) ?
 		NT_STATUS_OK : NT_STATUS_UNSUCCESSFUL;
 }
 
@@ -461,20 +520,32 @@ NTSTATUS pdb_default_set_aliasinfo(struct pdb_methods *methods,
 NTSTATUS pdb_default_add_aliasmem(struct pdb_methods *methods,
 				  const DOM_SID *alias, const DOM_SID *member)
 {
-	return add_aliasmem(alias, member);
+	if (!init_group_mapping()) {
+		DEBUG(0,("failed to initialize group mapping\n"));
+		return NT_STATUS_UNSUCCESSFUL;
+	}
+	return backend->add_aliasmem(alias, member);
 }
 
 NTSTATUS pdb_default_del_aliasmem(struct pdb_methods *methods,
 				  const DOM_SID *alias, const DOM_SID *member)
 {
-	return del_aliasmem(alias, member);
+	if (!init_group_mapping()) {
+		DEBUG(0,("failed to initialize group mapping\n"));
+		return NT_STATUS_UNSUCCESSFUL;
+	}
+	return backend->del_aliasmem(alias, member);
 }
 
 NTSTATUS pdb_default_enum_aliasmem(struct pdb_methods *methods,
 				   const DOM_SID *alias, DOM_SID **pp_members,
 				   size_t *p_num_members)
 {
-	return enum_aliasmem(alias, pp_members, p_num_members);
+	if (!init_group_mapping()) {
+		DEBUG(0,("failed to initialize group mapping\n"));
+		return NT_STATUS_UNSUCCESSFUL;
+	}
+	return backend->enum_aliasmem(alias, pp_members, p_num_members);
 }
 
 NTSTATUS pdb_default_alias_memberships(struct pdb_methods *methods,
@@ -489,6 +560,11 @@ NTSTATUS pdb_default_alias_memberships(struct pdb_methods *methods,
 	size_t i, num_alias_sids;
 	NTSTATUS result;
 
+	if (!init_group_mapping()) {
+		DEBUG(0,("failed to initialize group mapping\n"));
+		return NT_STATUS_UNSUCCESSFUL;
+	}
+
 	alias_sids = NULL;
 	num_alias_sids = 0;
 
diff --git a/source3/groupdb/mapping.h b/source3/groupdb/mapping.h
index 9daaa7fdd7..29e8ad5ffa 100644
--- a/source3/groupdb/mapping.h
+++ b/source3/groupdb/mapping.h
@@ -10,17 +10,22 @@
  */
 #define MEMBEROF_PREFIX "MEMBEROF/"
 
-/* internal prototypes */
-BOOL enum_group_mapping(const DOM_SID *domsid, enum lsa_SidType sid_name_use, GROUP_MAP **pp_rmap,
-			size_t *p_num_entries, BOOL unix_only);
-BOOL group_map_remove(const DOM_SID *sid);
-BOOL init_group_mapping(void);
-NTSTATUS one_alias_membership(const DOM_SID *member,
-			      DOM_SID **sids, size_t *num);
-BOOL get_group_map_from_sid(DOM_SID sid, GROUP_MAP *map);
-BOOL get_group_map_from_gid(gid_t gid, GROUP_MAP *map);
-BOOL get_group_map_from_ntname(const char *name, GROUP_MAP *map);
-BOOL add_mapping_entry(GROUP_MAP *map, int flag);
-NTSTATUS add_aliasmem(const DOM_SID *alias, const DOM_SID *member);
-NTSTATUS del_aliasmem(const DOM_SID *alias, const DOM_SID *member);
-NTSTATUS enum_aliasmem(const DOM_SID *alias, DOM_SID **sids, size_t *num);
+/*
+  groupdb mapping backend abstraction
+ */
+struct mapping_backend {
+	BOOL (*init_group_mapping)(void);
+	BOOL (*add_mapping_entry)(GROUP_MAP *map, int flag);
+	BOOL (*get_group_map_from_sid)(DOM_SID sid, GROUP_MAP *map);
+	BOOL (*get_group_map_from_gid)(gid_t gid, GROUP_MAP *map);
+	BOOL (*get_group_map_from_ntname)(const char *name, GROUP_MAP *map);
+	BOOL (*group_map_remove)(const DOM_SID *sid);
+	BOOL (*enum_group_mapping)(const DOM_SID *domsid, enum lsa_SidType sid_name_use, 
+				   GROUP_MAP **pp_rmap,
+				   size_t *p_num_entries, BOOL unix_only);
+	NTSTATUS (*one_alias_membership)(const DOM_SID *member,
+					 DOM_SID **sids, size_t *num);
+	NTSTATUS (*add_aliasmem)(const DOM_SID *alias, const DOM_SID *member);
+	NTSTATUS (*del_aliasmem)(const DOM_SID *alias, const DOM_SID *member);
+	NTSTATUS (*enum_aliasmem)(const DOM_SID *alias, DOM_SID **sids, size_t *num);
+};
diff --git a/source3/groupdb/mapping_ldb.c b/source3/groupdb/mapping_ldb.c
index a743c2456e..8eafc2532b 100644
--- a/source3/groupdb/mapping_ldb.c
+++ b/source3/groupdb/mapping_ldb.c
@@ -34,7 +34,7 @@ static BOOL mapping_upgrade(const char *tdb_path);
 /*
   connect to the group mapping ldb
 */
- BOOL init_group_mapping(void)
+static BOOL init_group_mapping(void)
 {
 	BOOL existed;
 	const char *init_ldif[] = 
@@ -128,16 +128,12 @@ static struct ldb_dn *mapping_dn(TALLOC_CTX *mem_ctx, const DOM_SID *sid)
 /*
   add a group mapping entry
  */
- BOOL add_mapping_entry(GROUP_MAP *map, int flag)
+static BOOL add_mapping_entry(GROUP_MAP *map, int flag)
 {
 	struct ldb_message *msg;	
 	int ret, i;
 	fstring string_sid;
 
-	if (!init_group_mapping()) {
-		return False;
-	}
-	
 	msg = ldb_msg_new(ldb);
 	if (msg == NULL) {
 		return False;
@@ -204,16 +200,12 @@ static BOOL msg_to_group_map(struct ldb_message *msg, GROUP_MAP *map)
 /*
  return a group map entry for a given sid
 */
- BOOL get_group_map_from_sid(DOM_SID sid, GROUP_MAP *map)
+static BOOL get_group_map_from_sid(DOM_SID sid, GROUP_MAP *map)
 {
 	int ret;
 	struct ldb_dn *dn;
 	struct ldb_result *res=NULL;
 	
-	if (!init_group_mapping()) {
-		return False;
-	}
-
 	dn = mapping_dn(ldb, &sid);
 	if (dn == NULL) goto failed;
 
@@ -236,16 +228,12 @@ failed:
 /*
  return a group map entry for a given gid
 */
- BOOL get_group_map_from_gid(gid_t gid, GROUP_MAP *map)
+static BOOL get_group_map_from_gid(gid_t gid, GROUP_MAP *map)
 {
 	int ret;
 	char *expr;
 	struct ldb_result *res=NULL;
 
-	if (!init_group_mapping()) {
-		return False;
-	}
-
 	expr = talloc_asprintf(ldb, "(&(gidNumber=%u)(objectClass=groupMap))", 
 			       (unsigned)gid);
 	if (expr == NULL) goto failed;
@@ -267,16 +255,12 @@ failed:
 /*
   Return the sid and the type of the unix group.
 */
- BOOL get_group_map_from_ntname(const char *name, GROUP_MAP *map)
+static BOOL get_group_map_from_ntname(const char *name, GROUP_MAP *map)
 {
 	int ret;
 	char *expr;
 	struct ldb_result *res=NULL;
 
-	if (!init_group_mapping()) {
-		return False;
-	}
-
 	expr = talloc_asprintf(ldb, "(&(ntName=%s)(objectClass=groupMap))", name);
 	if (expr == NULL) goto failed;
 
@@ -297,15 +281,11 @@ failed:
 /*
  Remove a group mapping entry.
 */
- BOOL group_map_remove(const DOM_SID *sid)
+static BOOL group_map_remove(const DOM_SID *sid)
 {
 	struct ldb_dn *dn;
 	int ret;
 	
-	if (!init_group_mapping()) {
-		return False;
-	}
-
 	dn = mapping_dn(ldb, sid);
 	if (dn == NULL) {
 		return False;
@@ -320,9 +300,9 @@ failed:
 /*
   Enumerate the group mappings for a domain
 */
- BOOL enum_group_mapping(const DOM_SID *domsid, enum lsa_SidType sid_name_use, 
-			 GROUP_MAP **pp_rmap,
-			 size_t *p_num_entries, BOOL unix_only)
+static BOOL enum_group_mapping(const DOM_SID *domsid, enum lsa_SidType sid_name_use, 
+			       GROUP_MAP **pp_rmap,
+			       size_t *p_num_entries, BOOL unix_only)
 {
 	int i, ret;
 	char *expr;
@@ -331,10 +311,6 @@ failed:
 	struct ldb_dn *basedn=NULL;
 	TALLOC_CTX *tmp_ctx;
 
-	if (!init_group_mapping()) {
-		return False;
-	}
-
 	tmp_ctx = talloc_new(ldb);
 	if (tmp_ctx == NULL) goto failed;
 
@@ -383,8 +359,8 @@ failed:
    This operation happens on session setup, so it should better be fast. We
    store a list of aliases a SID is member of hanging off MEMBEROF/SID. 
 */
- NTSTATUS one_alias_membership(const DOM_SID *member,
-			       DOM_SID **sids, size_t *num)
+static NTSTATUS one_alias_membership(const DOM_SID *member,
+				     DOM_SID **sids, size_t *num)
 {
 	const char *attrs[] = {
 		"sid",
@@ -397,10 +373,6 @@ failed:
 	fstring string_sid;
 	NTSTATUS status = NT_STATUS_INTERNAL_DB_CORRUPTION;
 
-	if (!init_group_mapping()) {
-		return NT_STATUS_ACCESS_DENIED;
-	}
-
       	if (!sid_to_string(string_sid, member)) {
 		return NT_STATUS_INVALID_PARAMETER;
 	}
@@ -451,10 +423,6 @@ static NTSTATUS modify_aliasmem(const DOM_SID *alias, const DOM_SID *member,
 	TALLOC_CTX *tmp_ctx;
 	GROUP_MAP map;
 
-	if (!init_group_mapping()) {
-		return NT_STATUS_ACCESS_DENIED;
-	}
-
 	if (!get_group_map_from_sid(*alias, &map)) {
 		sid_to_string(string_sid, alias);
 		return NT_STATUS_NO_SUCH_ALIAS;
@@ -500,12 +468,12 @@ static NTSTATUS modify_aliasmem(const DOM_SID *alias, const DOM_SID *member,
 	return (ret == LDB_SUCCESS ? NT_STATUS_OK : NT_STATUS_ACCESS_DENIED);
 }
 
- NTSTATUS add_aliasmem(const DOM_SID *alias, const DOM_SID *member)
+static NTSTATUS add_aliasmem(const DOM_SID *alias, const DOM_SID *member)
 {
 	return modify_aliasmem(alias, member, LDB_FLAG_MOD_ADD);
 }
 
- NTSTATUS del_aliasmem(const DOM_SID *alias, const DOM_SID *member)
+static NTSTATUS del_aliasmem(const DOM_SID *alias, const DOM_SID *member)
 {
 	return modify_aliasmem(alias, member, LDB_FLAG_MOD_DELETE);
 }
@@ -514,7 +482,7 @@ static NTSTATUS modify_aliasmem(const DOM_SID *alias, const DOM_SID *member,
 /*
   enumerate sids that have the given alias set in member
 */
- NTSTATUS enum_aliasmem(const DOM_SID *alias, DOM_SID **sids, size_t *num)
+static NTSTATUS enum_aliasmem(const DOM_SID *alias, DOM_SID **sids, size_t *num)
 {
 	const char *attrs[] = {
 		"member",
@@ -525,10 +493,6 @@ static NTSTATUS modify_aliasmem(const DOM_SID *alias, const DOM_SID *member,
 	struct ldb_dn *dn;
 	struct ldb_message_element *el;
 	
-	if (!init_group_mapping()) {
-		return NT_STATUS_ACCESS_DENIED;
-	}
-
 	*sids = NULL;
 	*num = 0;
 
@@ -576,7 +540,7 @@ static int upgrade_map_record(TDB_CONTEXT *tdb_ctx, TDB_DATA key,
 	int ret;
 	GROUP_MAP map;
 
-	if (strncmp(key.dptr, GROUP_PREFIX, 
+	if (strncmp((char *)key.dptr, GROUP_PREFIX, 
 		    MIN(key.dsize, strlen(GROUP_PREFIX))) != 0) {
 		return 0;
 	}
@@ -610,11 +574,11 @@ static int upgrade_map_record(TDB_CONTEXT *tdb_ctx, TDB_DATA key,
 static int upgrade_alias_record(TDB_CONTEXT *tdb_ctx, TDB_DATA key, 
 				TDB_DATA data, void *state)
 {
-	const char *p = data.dptr;
+	const char *p = (const char *)data.dptr;
 	fstring string_sid;
 	DOM_SID member;
 
-	if (strncmp(key.dptr, MEMBEROF_PREFIX, 
+	if (strncmp((char *)key.dptr, MEMBEROF_PREFIX, 
 		    MIN(key.dsize, strlen(MEMBEROF_PREFIX))) != 0) {
 		return 0;
 	}
@@ -684,3 +648,31 @@ failed:
 	if (tdb) tdb_close(tdb);
 	return False;
 }
+
+
+
+static const struct mapping_backend ldb_backend = {
+	.add_mapping_entry         = add_mapping_entry,
+	.get_group_map_from_sid    = get_group_map_from_sid,
+	.get_group_map_from_gid    = get_group_map_from_gid,
+	.get_group_map_from_ntname = get_group_map_from_ntname,
+	.group_map_remove          = group_map_remove,
+	.enum_group_mapping        = enum_group_mapping,
+	.one_alias_membership      = one_alias_membership,
+	.add_aliasmem              = add_aliasmem,
+	.del_aliasmem              = del_aliasmem,
+	.enum_aliasmem             = enum_aliasmem	
+};
+
+/*
+  initialise the ldb mapping backend
+ */
+const struct mapping_backend *groupdb_ldb_init(void)
+{
+	if (!init_group_mapping()) {
+		DEBUG(0,("Failed to initialise ldb mapping backend\n"));
+		return NULL;
+	}
+
+	return &ldb_backend;
+}
diff --git a/source3/groupdb/mapping_tdb.c b/source3/groupdb/mapping_tdb.c
index 2461ece1d6..7ea7ec498c 100644
--- a/source3/groupdb/mapping_tdb.c
+++ b/source3/groupdb/mapping_tdb.c
@@ -26,10 +26,14 @@
 
 static TDB_CONTEXT *tdb; /* used for driver files */
 
+static BOOL enum_group_mapping(const DOM_SID *domsid, enum lsa_SidType sid_name_use, GROUP_MAP **pp_rmap,
+			       size_t *p_num_entries, BOOL unix_only);
+static BOOL group_map_remove(const DOM_SID *sid);
+	
 /****************************************************************************
  Open the group mapping tdb.
 ****************************************************************************/
- BOOL init_group_mapping(void)
+static BOOL init_group_mapping(void)
 {
 	const char *vstring = "INFO/version";
 	int32 vers_id;
@@ -85,18 +89,13 @@ static TDB_CONTEXT *tdb; /* used for driver files */
 
 /****************************************************************************
 ****************************************************************************/
- BOOL add_mapping_entry(GROUP_MAP *map, int flag)
+static BOOL add_mapping_entry(GROUP_MAP *map, int flag)
 {
 	TDB_DATA dbuf;
 	pstring key, buf;
 	fstring string_sid="";
 	int len;
 
-	if(!init_group_mapping()) {
-		DEBUG(0,("failed to initialize group mapping\n"));
-		return(False);
-	}
-	
 	sid_to_string(string_sid, &map->sid);
 
 	len = tdb_pack((uint8 *)buf, sizeof(buf), "ddff",
@@ -119,18 +118,13 @@ static TDB_CONTEXT *tdb; /* used for driver files */
  Return the sid and the type of the unix group.
 ****************************************************************************/
 
- BOOL get_group_map_from_sid(DOM_SID sid, GROUP_MAP *map)
+static BOOL get_group_map_from_sid(DOM_SID sid, GROUP_MAP *map)
 {
 	TDB_DATA dbuf;
 	pstring key;
 	fstring string_sid;
 	int ret = 0;
 	
-	if(!init_group_mapping()) {
-		DEBUG(0,("failed to initialize group mapping\n"));
-		return(False);
-	}
-
 	/* the key is the SID, retrieving is direct */
 
 	sid_to_string(string_sid, &sid);
@@ -159,17 +153,12 @@ static TDB_CONTEXT *tdb; /* used for driver files */
  Return the sid and the type of the unix group.
 ****************************************************************************/
 
- BOOL get_group_map_from_gid(gid_t gid, GROUP_MAP *map)
+static BOOL get_group_map_from_gid(gid_t gid, GROUP_MAP *map)
 {
 	TDB_DATA kbuf, dbuf, newkey;
 	fstring string_sid;
 	int ret;
 
-	if(!init_group_mapping()) {
-		DEBUG(0,("failed to initialize group mapping\n"));
-		return(False);
-	}
-
 	/* we need to enumerate the TDB to find the GID */
 
 	for (kbuf = tdb_firstkey(tdb); 
@@ -209,17 +198,12 @@ static TDB_CONTEXT *tdb; /* used for driver files */
  Return the sid and the type of the unix group.
 ****************************************************************************/
 
- BOOL get_group_map_from_ntname(const char *name, GROUP_MAP *map)
+static BOOL get_group_map_from_ntname(const char *name, GROUP_MAP *map)
 {
 	TDB_DATA kbuf, dbuf, newkey;
 	fstring string_sid;
 	int ret;
 
-	if(!init_group_mapping()) {
-		DEBUG(0,("get_group_map_from_ntname:failed to initialize group mapping\n"));
-		return(False);
-	}
-
 	/* we need to enumerate the TDB to find the name */
 
 	for (kbuf = tdb_firstkey(tdb); 
@@ -259,17 +243,12 @@ static TDB_CONTEXT *tdb; /* used for driver files */
  Remove a group mapping entry.
 ****************************************************************************/
 
-BOOL group_map_remove(const DOM_SID *sid)
+static BOOL group_map_remove(const DOM_SID *sid)
 {
 	TDB_DATA dbuf;
 	pstring key;
 	fstring string_sid;
 	
-	if(!init_group_mapping()) {
-		DEBUG(0,("failed to initialize group mapping\n"));
-		return(False);
-	}
-
 	/* the key is the SID, retrieving is direct */
 
 	sid_to_string(string_sid, sid);
@@ -291,7 +270,7 @@ BOOL group_map_remove(const DOM_SID *sid)
  Enumerate the group mapping.
 ****************************************************************************/
 
-BOOL enum_group_mapping(const DOM_SID *domsid, enum lsa_SidType sid_name_use, GROUP_MAP **pp_rmap,
+static BOOL enum_group_mapping(const DOM_SID *domsid, enum lsa_SidType sid_name_use, GROUP_MAP **pp_rmap,
 			size_t *p_num_entries, BOOL unix_only)
 {
 	TDB_DATA kbuf, dbuf, newkey;
@@ -303,11 +282,6 @@ BOOL enum_group_mapping(const DOM_SID *domsid, enum lsa_SidType sid_name_use, GR
 	DOM_SID grpsid;
 	uint32 rid;
 
-	if(!init_group_mapping()) {
-		DEBUG(0,("failed to initialize group mapping\n"));
-		return(False);
-	}
-
 	*p_num_entries=0;
 	*pp_rmap=NULL;
 
@@ -388,18 +362,13 @@ BOOL enum_group_mapping(const DOM_SID *domsid, enum lsa_SidType sid_name_use, GR
 /* This operation happens on session setup, so it should better be fast. We
  * store a list of aliases a SID is member of hanging off MEMBEROF/SID. */
 
- NTSTATUS one_alias_membership(const DOM_SID *member,
+static NTSTATUS one_alias_membership(const DOM_SID *member,
 			       DOM_SID **sids, size_t *num)
 {
 	fstring key, string_sid;
 	TDB_DATA dbuf;
 	const char *p;
 
-	if (!init_group_mapping()) {
-		DEBUG(0,("failed to initialize group mapping\n"));
-		return NT_STATUS_ACCESS_DENIED;
-	}
-
 	sid_to_string(string_sid, member);
 	slprintf(key, sizeof(key), "%s%s", MEMBEROF_PREFIX, string_sid);
 
@@ -464,7 +433,7 @@ static BOOL is_aliasmem(const DOM_SID *alias, const DOM_SID *member)
 }
 
 
- NTSTATUS add_aliasmem(const DOM_SID *alias, const DOM_SID *member)
+static NTSTATUS add_aliasmem(const DOM_SID *alias, const DOM_SID *member)
 {
 	GROUP_MAP map;
 	TDB_DATA dbuf;
@@ -473,11 +442,6 @@ static BOOL is_aliasmem(const DOM_SID *alias, const DOM_SID *member)
 	char *new_memberstring;
 	int result;
 
-	if(!init_group_mapping()) {
-		DEBUG(0,("failed to initialize group mapping\n"));
-		return NT_STATUS_ACCESS_DENIED;
-	}
-
 	if (!get_group_map_from_sid(*alias, &map))
 		return NT_STATUS_NO_SUCH_ALIAS;
 
@@ -570,16 +534,11 @@ static int collect_aliasmem(TDB_CONTEXT *tdb_ctx, TDB_DATA key, TDB_DATA data,
 	return 0;
 }
 
- NTSTATUS enum_aliasmem(const DOM_SID *alias, DOM_SID **sids, size_t *num)
+static NTSTATUS enum_aliasmem(const DOM_SID *alias, DOM_SID **sids, size_t *num)
 {
 	GROUP_MAP map;
 	struct aliasmem_closure closure;
 
-	if(!init_group_mapping()) {
-		DEBUG(0,("failed to initialize group mapping\n"));
-		return NT_STATUS_ACCESS_DENIED;
-	}
-
 	if (!get_group_map_from_sid(*alias, &map))
 		return NT_STATUS_NO_SUCH_ALIAS;
 
@@ -598,7 +557,7 @@ static int collect_aliasmem(TDB_CONTEXT *tdb_ctx, TDB_DATA key, TDB_DATA data,
 	return NT_STATUS_OK;
 }
 
- NTSTATUS del_aliasmem(const DOM_SID *alias, const DOM_SID *member)
+static NTSTATUS del_aliasmem(const DOM_SID *alias, const DOM_SID *member)
 {
 	NTSTATUS result;
 	DOM_SID *sids;
@@ -669,3 +628,29 @@ static int collect_aliasmem(TDB_CONTEXT *tdb_ctx, TDB_DATA key, TDB_DATA data,
 	return result;
 }
 
+
+static const struct mapping_backend tdb_backend = {
+	.add_mapping_entry         = add_mapping_entry,
+	.get_group_map_from_sid    = get_group_map_from_sid,
+	.get_group_map_from_gid    = get_group_map_from_gid,
+	.get_group_map_from_ntname = get_group_map_from_ntname,
+	.group_map_remove          = group_map_remove,
+	.enum_group_mapping        = enum_group_mapping,
+	.one_alias_membership      = one_alias_membership,
+	.add_aliasmem              = add_aliasmem,
+	.del_aliasmem              = del_aliasmem,
+	.enum_aliasmem             = enum_aliasmem	
+};
+
+/*
+  initialise the tdb mapping backend
+ */
+const struct mapping_backend *groupdb_tdb_init(void)
+{
+	if (!init_group_mapping()) {
+		DEBUG(0,("Failed to initialise tdb mapping backend\n"));
+		return NULL;
+	}
+
+	return &tdb_backend;
+}