s3:winbindd add idmap_tdb_common file to store common code of TDB idmap backends

4 files changed, 796 insertions, 2 deletions

diff --git a/source3/Makefile.in b/source3/Makefile.in
index 37419de5e5..184dd1fed2 100644
--- a/source3/Makefile.in
+++ b/source3/Makefile.in
@@ -1374,7 +1374,10 @@ PAM_SMBPASS_OBJ = $(PAM_SMBPASS_OBJ_0) $(PARAM_OBJ) $(LIB_NONSMBD_OBJ) $(PASSDB_
 
 IDMAP_RW_OBJ = winbindd/idmap_rw.o
 
-IDMAP_OBJ     = winbindd/idmap.o winbindd/idmap_util.o $(IDMAP_RW_OBJ) @IDMAP_STATIC@
+IDMAP_TDB_COMMON_OBJ = winbindd/idmap_tdb_common.o
+
+IDMAP_OBJ     = winbindd/idmap.o winbindd/idmap_util.o $(IDMAP_RW_OBJ) \
+		$(IDMAP_TDB_COMMON_OBJ) @IDMAP_STATIC@
 
 NSS_INFO_OBJ = winbindd/nss_info.o @NSS_INFO_STATIC@
 
diff --git a/source3/winbindd/idmap_tdb_common.c b/source3/winbindd/idmap_tdb_common.c
new file mode 100644
index 0000000000..ca6f6d8e08
--- /dev/null
+++ b/source3/winbindd/idmap_tdb_common.c
@@ -0,0 +1,654 @@
+/*
+   Unix SMB/CIFS implementation.
+
+   common functions for TDB based idmapping backends
+
+   Copyright (C) Christian Ambach 2012
+
+   These functions were initially copied over from idmap_tdb.c and idmap_tdb2.c
+   which are:
+
+   Copyright (C) Tim Potter 2000
+   Copyright (C) Jim McDonough <jmcd@us.ibm.com> 2003
+   Copyright (C) Jeremy Allison 2006
+   Copyright (C) Simo Sorce 2003-2006
+   Copyright (C) Michael Adam 2009-2010
+   Copyright (C) Andrew Tridgell 2007
+
+   This program is free software; you can redistribute it and/or modify
+   it under the terms of the GNU General Public License as published by
+   the Free Software Foundation; either version 2 of the License, or
+   (at your option) any later version.
+
+   This program is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+   GNU General Public License for more details.
+
+   You should have received a copy of the GNU General Public License
+   along with this program; if not, write to the Free Software
+   Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
+*/
+
+#include "includes.h"
+#include "idmap_tdb_common.h"
+#include "dbwrap/dbwrap.h"
+#include "util_tdb.h"
+#include "idmap_rw.h"
+#include "../libcli/security/dom_sid.h"
+
+#undef DBGC_CLASS
+#define DBGC_CLASS DBGC_IDMAP
+
+struct idmap_tdb_common_allocate_id_context {
+	const char *hwmkey;
+	const char *hwmtype;
+	uint32_t high_hwm;
+	uint32_t hwm;
+};
+
+static NTSTATUS idmap_tdb_common_allocate_id_action(struct db_context *db,
+						    void *private_data)
+{
+	NTSTATUS ret;
+	struct idmap_tdb_common_allocate_id_context *state;
+	uint32_t hwm;
+
+	state = (struct idmap_tdb_common_allocate_id_context *)private_data;
+
+	ret = dbwrap_fetch_uint32(db, state->hwmkey, &hwm);
+	if (!NT_STATUS_IS_OK(ret)) {
+		ret = NT_STATUS_INTERNAL_DB_ERROR;
+		goto done;
+	}
+
+	/* check it is in the range */
+	if (hwm > state->high_hwm) {
+		DEBUG(1, ("Fatal Error: %s range full!! (max: %lu)\n",
+			  state->hwmtype, (unsigned long)state->high_hwm));
+		ret = NT_STATUS_UNSUCCESSFUL;
+		goto done;
+	}
+
+	/* fetch a new id and increment it */
+	ret = dbwrap_change_uint32_atomic(db, state->hwmkey, &hwm, 1);
+	if (!NT_STATUS_IS_OK(ret)) {
+		DEBUG(1, ("Fatal error while fetching a new %s value\n!",
+			  state->hwmtype));
+		goto done;
+	}
+
+	/* recheck it is in the range */
+	if (hwm > state->high_hwm) {
+		DEBUG(1, ("Fatal Error: %s range full!! (max: %lu)\n",
+			  state->hwmtype, (unsigned long)state->high_hwm));
+		ret = NT_STATUS_UNSUCCESSFUL;
+		goto done;
+	}
+
+	ret = NT_STATUS_OK;
+	state->hwm = hwm;
+
+      done:
+	return ret;
+}
+
+static NTSTATUS idmap_tdb_common_allocate_id(struct idmap_domain *dom,
+					     struct unixid *xid)
+{
+	const char *hwmkey;
+	const char *hwmtype;
+	uint32_t hwm = 0;
+	NTSTATUS status;
+	struct idmap_tdb_common_allocate_id_context state;
+	struct idmap_tdb_common_context *ctx;
+
+	ctx =
+	    talloc_get_type_abort(dom->private_data,
+				  struct idmap_tdb_common_context);
+
+	/* Get current high water mark */
+	switch (xid->type) {
+
+	case ID_TYPE_UID:
+		hwmkey = ctx->hwmkey_uid;
+		hwmtype = "UID";
+		break;
+
+	case ID_TYPE_GID:
+		hwmkey = ctx->hwmkey_gid;
+		hwmtype = "GID";
+		break;
+
+	default:
+		DEBUG(2, ("Invalid ID type (0x%x)\n", xid->type));
+		return NT_STATUS_INVALID_PARAMETER;
+	}
+
+	state.hwm = hwm;
+	state.high_hwm = ctx->max_id;
+	state.hwmtype = hwmtype;
+	state.hwmkey = hwmkey;
+
+	status = dbwrap_trans_do(ctx->db, idmap_tdb_common_allocate_id_action,
+				 &state);
+
+	if (NT_STATUS_IS_OK(status)) {
+		xid->id = state.hwm;
+		DEBUG(10, ("New %s = %d\n", hwmtype, state.hwm));
+	} else {
+		DEBUG(1, ("Error allocating a new %s\n", hwmtype));
+	}
+
+	return status;
+}
+
+/**
+ * Allocate a new unix-ID.
+ * For now this is for the default idmap domain only.
+ * Should be extended later on.
+ */
+NTSTATUS idmap_tdb_common_get_new_id(struct idmap_domain * dom,
+				     struct unixid * id)
+{
+	NTSTATUS ret;
+
+	if (!strequal(dom->name, "*")) {
+		DEBUG(3, ("idmap_tdb_common_get_new_id: "
+			  "Refusing allocation of a new unixid for domain'%s'. "
+			  "Currently only supported for the default "
+			  "domain \"*\".\n", dom->name));
+		return NT_STATUS_NOT_IMPLEMENTED;
+	}
+
+	ret = idmap_tdb_common_allocate_id(dom, id);
+
+	return ret;
+}
+
+/**
+ * store a mapping in the database.
+ */
+
+struct idmap_tdb_common_set_mapping_context {
+	const char *ksidstr;
+	const char *kidstr;
+};
+
+static NTSTATUS idmap_tdb_common_set_mapping_action(struct db_context *db,
+						    void *private_data)
+{
+	TDB_DATA data;
+	NTSTATUS ret;
+	struct idmap_tdb_common_set_mapping_context *state;
+	TALLOC_CTX *tmp_ctx = talloc_stackframe();
+
+	state = (struct idmap_tdb_common_set_mapping_context *)private_data;
+
+	DEBUG(10, ("Storing %s <-> %s map\n", state->ksidstr, state->kidstr));
+
+	/* check whether sid mapping is already present in db */
+	ret = dbwrap_fetch_bystring(db, tmp_ctx, state->ksidstr, &data);
+	if (NT_STATUS_IS_OK(ret)) {
+		ret = NT_STATUS_OBJECT_NAME_COLLISION;
+		goto done;
+	}
+
+	ret = dbwrap_store_bystring(db, state->ksidstr,
+				    string_term_tdb_data(state->kidstr),
+				    TDB_INSERT);
+	if (!NT_STATUS_IS_OK(ret)) {
+		DEBUG(0, ("Error storing SID -> ID: %s\n", nt_errstr(ret)));
+		goto done;
+	}
+
+	ret = dbwrap_store_bystring(db, state->kidstr,
+				    string_term_tdb_data(state->ksidstr),
+				    TDB_INSERT);
+	if (!NT_STATUS_IS_OK(ret)) {
+		DEBUG(0, ("Error storing ID -> SID: %s\n", nt_errstr(ret)));
+		/* try to remove the previous stored SID -> ID map */
+		dbwrap_delete_bystring(db, state->ksidstr);
+		goto done;
+	}
+
+	DEBUG(10, ("Stored %s <-> %s\n", state->ksidstr, state->kidstr));
+
+      done:
+	talloc_free(tmp_ctx);
+	return ret;
+}
+
+NTSTATUS idmap_tdb_common_set_mapping(struct idmap_domain * dom,
+				      const struct id_map * map)
+{
+	struct idmap_tdb_common_context *ctx;
+	struct idmap_tdb_common_set_mapping_context state;
+	NTSTATUS ret;
+	char *ksidstr, *kidstr;
+
+	if (!map || !map->sid) {
+		return NT_STATUS_INVALID_PARAMETER;
+	}
+
+	ksidstr = kidstr = NULL;
+
+	/* TODO: should we filter a set_mapping using low/high filters ? */
+
+	ctx =
+	    talloc_get_type_abort(dom->private_data,
+				  struct idmap_tdb_common_context);
+
+	switch (map->xid.type) {
+
+	case ID_TYPE_UID:
+		kidstr =
+		    talloc_asprintf(ctx, "UID %lu", (unsigned long)map->xid.id);
+		break;
+
+	case ID_TYPE_GID:
+		kidstr =
+		    talloc_asprintf(ctx, "GID %lu", (unsigned long)map->xid.id);
+		break;
+
+	default:
+		DEBUG(2, ("INVALID unix ID type: 0x02%x\n", map->xid.type));
+		return NT_STATUS_INVALID_PARAMETER;
+	}
+
+	if (kidstr == NULL) {
+		DEBUG(0, ("ERROR: Out of memory!\n"));
+		ret = NT_STATUS_NO_MEMORY;
+		goto done;
+	}
+
+	ksidstr = sid_string_talloc(ctx, map->sid);
+	if (ksidstr == NULL) {
+		DEBUG(0, ("Out of memory!\n"));
+		ret = NT_STATUS_NO_MEMORY;
+		goto done;
+	}
+
+	state.ksidstr = ksidstr;
+	state.kidstr = kidstr;
+
+	ret = dbwrap_trans_do(ctx->db, idmap_tdb_common_set_mapping_action,
+			      &state);
+
+      done:
+	talloc_free(ksidstr);
+	talloc_free(kidstr);
+	return ret;
+}
+
+/*
+ * Create a new mapping for an unmapped SID, also allocating a new ID.
+ * This should be run inside a transaction.
+ *
+ * TODO:
+ *  Properly integrate this with multi domain idmap config:
+ *  Currently, the allocator is default-config only.
+ */
+NTSTATUS idmap_tdb_common_new_mapping(struct idmap_domain * dom,
+				      struct id_map * map)
+{
+	NTSTATUS ret;
+	struct idmap_tdb_common_context *ctx;
+
+	ctx =
+	    talloc_get_type_abort(dom->private_data,
+				  struct idmap_tdb_common_context);
+
+	ret = idmap_rw_new_mapping(dom, ctx->rw_ops, map);
+
+	return ret;
+}
+
+/*
+  lookup a set of unix ids
+*/
+NTSTATUS idmap_tdb_common_unixids_to_sids(struct idmap_domain * dom,
+					  struct id_map ** ids)
+{
+	NTSTATUS ret;
+	int i, num_mapped = 0;
+	struct idmap_tdb_common_context *ctx;
+
+	NTSTATUS(*unixid_to_sid_fn) (struct idmap_domain * dom,
+				     struct id_map * map);
+	ctx =
+	    talloc_get_type_abort(dom->private_data,
+				  struct idmap_tdb_common_context);
+
+	unixid_to_sid_fn =
+	    (ctx->unixid_to_sid_fn ==
+	     NULL) ? idmap_tdb_common_unixid_to_sid : ctx->unixid_to_sid_fn;
+
+	/* initialize the status to avoid surprise */
+	for (i = 0; ids[i]; i++) {
+		ids[i]->status = ID_UNKNOWN;
+	}
+
+	for (i = 0; ids[i]; i++) {
+		ret = unixid_to_sid_fn(dom, ids[i]);
+		if (!NT_STATUS_IS_OK(ret)) {
+
+			/* if it is just a failed mapping continue */
+			if (NT_STATUS_EQUAL(ret, NT_STATUS_NONE_MAPPED)) {
+
+				/* make sure it is marked as unmapped */
+				ids[i]->status = ID_UNMAPPED;
+				continue;
+			}
+
+			/* some fatal error occurred, return immediately */
+			goto done;
+		}
+
+		/* all ok, id is mapped */
+		ids[i]->status = ID_MAPPED;
+		num_mapped += 1;
+	}
+
+	ret = NT_STATUS_OK;
+
+done:
+
+	if (NT_STATUS_IS_OK(ret)) {
+		if (i == 0 || num_mapped == 0) {
+			ret = NT_STATUS_NONE_MAPPED;
+		} else if (num_mapped < i) {
+			ret = STATUS_SOME_UNMAPPED;
+		} else {
+			ret = NT_STATUS_OK;
+		}
+	}
+
+	return ret;
+}
+
+/*
+  default single id to sid lookup function
+*/
+NTSTATUS idmap_tdb_common_unixid_to_sid(struct idmap_domain * dom,
+					struct id_map * map)
+{
+	NTSTATUS ret;
+	TDB_DATA data;
+	char *keystr;
+	struct idmap_tdb_common_context *ctx;
+
+	if (!dom || !map) {
+		return NT_STATUS_INVALID_PARAMETER;
+	}
+/* TODO: do we really make sure the database is open again? should have been
+ * done while initing the module
+	status = idmap_tdb2_open_db(dom);
+	NT_STATUS_NOT_OK_RETURN(status);
+*/
+	ctx =
+	    talloc_get_type_abort(dom->private_data,
+				  struct idmap_tdb_common_context);
+
+	/* apply filters before checking */
+	if (!idmap_unix_id_is_in_range(map->xid.id, dom)) {
+		DEBUG(5,
+		      ("Requested id (%u) out of range (%u - %u). Filtered!\n",
+		       map->xid.id, dom->low_id, dom->high_id));
+		return NT_STATUS_NONE_MAPPED;
+	}
+
+	switch (map->xid.type) {
+
+	case ID_TYPE_UID:
+		keystr =
+		    talloc_asprintf(ctx, "UID %lu", (unsigned long)map->xid.id);
+		break;
+
+	case ID_TYPE_GID:
+		keystr =
+		    talloc_asprintf(ctx, "GID %lu", (unsigned long)map->xid.id);
+		break;
+
+	default:
+		DEBUG(2, ("INVALID unix ID type: 0x02%x\n", map->xid.type));
+		return NT_STATUS_INVALID_PARAMETER;
+	}
+
+	if (keystr == NULL) {
+		DEBUG(0, ("Out of memory!\n"));
+		ret = NT_STATUS_NO_MEMORY;
+		goto done;
+	}
+
+	DEBUG(10, ("Fetching record %s\n", keystr));
+
+	/* Check if the mapping exists */
+	ret = dbwrap_fetch_bystring(ctx->db, keystr, keystr, &data);
+
+	if (!NT_STATUS_IS_OK(ret)) {
+		DEBUG(10, ("Record %s not found\n", keystr));
+		ret = NT_STATUS_NONE_MAPPED;
+		goto done;
+	}
+
+	if (!string_to_sid(map->sid, (const char *)data.dptr)) {
+		DEBUG(10, ("INVALID SID (%s) in record %s\n",
+			   (const char *)data.dptr, keystr));
+		ret = NT_STATUS_INTERNAL_DB_ERROR;
+		goto done;
+	}
+
+	DEBUG(10, ("Found record %s -> %s\n", keystr, (const char *)data.dptr));
+	ret = NT_STATUS_OK;
+
+      done:
+	talloc_free(keystr);
+	return ret;
+}
+
+/**********************************
+ Single sid to id lookup function.
+**********************************/
+
+NTSTATUS idmap_tdb_common_sid_to_unixid(struct idmap_domain * dom,
+					struct id_map * map)
+{
+	NTSTATUS ret;
+	TDB_DATA data;
+	char *keystr;
+	unsigned long rec_id = 0;
+	struct idmap_tdb_common_context *ctx;
+	TALLOC_CTX *tmp_ctx = talloc_stackframe();
+
+	if (!dom || !map) {
+		return NT_STATUS_INVALID_PARAMETER;
+	}
+
+	ctx =
+	    talloc_get_type_abort(dom->private_data,
+				  struct idmap_tdb_common_context);
+
+	keystr = sid_string_talloc(tmp_ctx, map->sid);
+	if (keystr == NULL) {
+		DEBUG(0, ("Out of memory!\n"));
+		ret = NT_STATUS_NO_MEMORY;
+		goto done;
+	}
+
+	DEBUG(10, ("Fetching record %s\n", keystr));
+
+	/* Check if sid is present in database */
+	ret = dbwrap_fetch_bystring(ctx->db, tmp_ctx, keystr, &data);
+	if (!NT_STATUS_IS_OK(ret)) {
+		DEBUG(10, ("Record %s not found\n", keystr));
+		ret = NT_STATUS_NONE_MAPPED;
+		goto done;
+	}
+
+	/* What type of record is this ? */
+	if (sscanf((const char *)data.dptr, "UID %lu", &rec_id) == 1) {
+		/* Try a UID record. */
+		map->xid.id = rec_id;
+		map->xid.type = ID_TYPE_UID;
+		DEBUG(10,
+		      ("Found uid record %s -> %s \n", keystr,
+		       (const char *)data.dptr));
+		ret = NT_STATUS_OK;
+
+	} else if (sscanf((const char *)data.dptr, "GID %lu", &rec_id) == 1) {
+		/* Try a GID record. */
+		map->xid.id = rec_id;
+		map->xid.type = ID_TYPE_GID;
+		DEBUG(10,
+		      ("Found gid record %s -> %s \n", keystr,
+		       (const char *)data.dptr));
+		ret = NT_STATUS_OK;
+
+	} else {		/* Unknown record type ! */
+		DEBUG(2,
+		      ("Found INVALID record %s -> %s\n", keystr,
+		       (const char *)data.dptr));
+		ret = NT_STATUS_INTERNAL_DB_ERROR;
+		goto done;
+	}
+
+	/* apply filters before returning result */
+	if (!idmap_unix_id_is_in_range(map->xid.id, dom)) {
+		DEBUG(5,
+		      ("Requested id (%u) out of range (%u - %u). Filtered!\n",
+		       map->xid.id, dom->low_id, dom->high_id));
+		ret = NT_STATUS_NONE_MAPPED;
+	}
+
+      done:
+	talloc_free(tmp_ctx);
+	return ret;
+}
+
+/**********************************
+ lookup a set of sids
+**********************************/
+
+struct idmap_tdb_common_sids_to_unixids_context {
+	struct idmap_domain *dom;
+	struct id_map **ids;
+	bool allocate_unmapped;
+	 NTSTATUS(*sid_to_unixid_fn) (struct idmap_domain * dom,
+				      struct id_map * map);
+};
+
+static NTSTATUS idmap_tdb_common_sids_to_unixids_action(struct db_context *db,
+							void *private_data)
+{
+	struct idmap_tdb_common_sids_to_unixids_context *state;
+	int i, num_mapped = 0;
+	NTSTATUS ret = NT_STATUS_OK;
+
+	state = (struct idmap_tdb_common_sids_to_unixids_context *)private_data;
+
+	DEBUG(10, ("idmap_tdb_common_sids_to_unixids: "
+		   " domain: [%s], allocate: %s\n",
+		   state->dom->name, state->allocate_unmapped ? "yes" : "no"));
+
+	for (i = 0; state->ids[i]; i++) {
+		if ((state->ids[i]->status == ID_UNKNOWN) ||
+		    /* retry if we could not map in previous run: */
+		    (state->ids[i]->status == ID_UNMAPPED)) {
+			NTSTATUS ret2;
+
+			ret2 = state->sid_to_unixid_fn(state->dom,
+					state->ids[i]);
+
+			if (!NT_STATUS_IS_OK(ret2)) {
+
+				/* if it is just a failed mapping, continue */
+				if (NT_STATUS_EQUAL
+				    (ret2, NT_STATUS_NONE_MAPPED)) {
+
+					/* make sure it is marked as unmapped */
+					state->ids[i]->status = ID_UNMAPPED;
+					ret = STATUS_SOME_UNMAPPED;
+				} else {
+					/*
+					 * some fatal error occurred,
+					 * return immediately
+					 */
+					ret = ret2;
+					goto done;
+				}
+			} else {
+				/* all ok, id is mapped */
+				state->ids[i]->status = ID_MAPPED;
+			}
+		}
+
+		if ((state->ids[i]->status == ID_MAPPED)) {
+			num_mapped += 1;
+		}
+
+		if ((state->ids[i]->status == ID_UNMAPPED) &&
+		    state->allocate_unmapped) {
+			ret =
+			    idmap_tdb_common_new_mapping(state->dom,
+							 state->ids[i]);
+			if (!NT_STATUS_IS_OK(ret)) {
+				goto done;
+			}
+			num_mapped += 1;
+		}
+	}
+
+done:
+
+	if (NT_STATUS_IS_OK(ret) ||
+	    NT_STATUS_EQUAL(ret, STATUS_SOME_UNMAPPED)) {
+		if (i == 0 || num_mapped == 0) {
+			ret = NT_STATUS_NONE_MAPPED;
+		} else if (num_mapped < i) {
+			ret = STATUS_SOME_UNMAPPED;
+		} else {
+			ret = NT_STATUS_OK;
+		}
+	}
+
+	return ret;
+}
+
+NTSTATUS idmap_tdb_common_sids_to_unixids(struct idmap_domain * dom,
+					  struct id_map ** ids)
+{
+	NTSTATUS ret;
+	int i;
+	struct idmap_tdb_common_sids_to_unixids_context state;
+	struct idmap_tdb_common_context *ctx;
+
+	ctx =
+	    talloc_get_type_abort(dom->private_data,
+				  struct idmap_tdb_common_context);
+
+	/* initialize the status to avoid surprise */
+	for (i = 0; ids[i]; i++) {
+		ids[i]->status = ID_UNKNOWN;
+	}
+
+	state.dom = dom;
+	state.ids = ids;
+	state.allocate_unmapped = false;
+	state.sid_to_unixid_fn =
+	    (ctx->sid_to_unixid_fn ==
+	     NULL) ? idmap_tdb_common_sid_to_unixid : ctx->sid_to_unixid_fn;
+
+	ret = idmap_tdb_common_sids_to_unixids_action(ctx->db, &state);
+
+	if ( (NT_STATUS_EQUAL(ret, STATUS_SOME_UNMAPPED) ||
+	      NT_STATUS_EQUAL(ret, NT_STATUS_NONE_MAPPED)) &&
+	     !dom->read_only) {
+		state.allocate_unmapped = true;
+		ret = dbwrap_trans_do(ctx->db,
+				      idmap_tdb_common_sids_to_unixids_action,
+				      &state);
+	}
+
+	return ret;
+}
diff --git a/source3/winbindd/idmap_tdb_common.h b/source3/winbindd/idmap_tdb_common.h
new file mode 100644
index 0000000000..3343b58c21
--- /dev/null
+++ b/source3/winbindd/idmap_tdb_common.h
@@ -0,0 +1,137 @@
+/*
+   Unix SMB/CIFS implementation.
+
+   common functions for TDB based idmapping backends
+
+   Copyright (C) Christian Ambach 2012
+
+   These functions were initially copied over from idmap_tdb.c and idmap_tdb2.c
+   which are:
+
+   Copyright (C) Tim Potter 2000
+   Copyright (C) Jim McDonough <jmcd@us.ibm.com> 2003
+   Copyright (C) Jeremy Allison 2006
+   Copyright (C) Simo Sorce 2003-2006
+   Copyright (C) Michael Adam 2009-2010
+   Copyright (C) Andrew Tridgell 2007
+
+   This program is free software; you can redistribute it and/or modify
+   it under the terms of the GNU General Public License as published by
+   the Free Software Foundation; either version 2 of the License, or
+   (at your option) any later version.
+
+   This program is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+   GNU General Public License for more details.
+
+   You should have received a copy of the GNU General Public License
+   along with this program; if not, write to the Free Software
+   Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
+*/
+
+#ifndef _IDMAP_TDB_COMMON_H_
+#define _IDMAP_TDB_COMMON_H_
+
+#include "includes.h"
+#include "idmap.h"
+#include "dbwrap/dbwrap.h"
+
+/*
+ * this must be stored in idmap_domain->private_data
+ * when using idmap_tdb_common_get_new_id and the
+ * mapping functions idmap_tdb_common_unixid(s)_to_sids
+ *
+ * private_data can be used for backend specific
+ * configuration data (e.g. idmap script in idmap_tdb2)
+ *
+ */
+struct idmap_tdb_common_context {
+	struct db_context *db;
+	struct idmap_rw_ops *rw_ops;
+	/*
+	 * what is the maximum xid to be allocated
+	 * this is typically just dom->high_id
+	 */
+	uint32_t max_id;
+	const char *hwmkey_uid;
+	const char *hwmkey_gid;
+	/**
+	 * if not set, idmap_tdb_common_unixids_to_sid will be used by
+	 * idmap_tdb_common_unixids_to_sids
+	 */
+	NTSTATUS(*unixid_to_sid_fn) (struct idmap_domain *dom,
+				     struct id_map * map);
+	/*
+	 * if not set, idmap_tdb_common_sid_to_id will be used by
+	 * idmap_tdb_common_sids_to_unixids
+	 */
+	NTSTATUS(*sid_to_unixid_fn) (struct idmap_domain *dom,
+				     struct id_map * map);
+	void *private_data;
+};
+
+/**
+ * Allocate a new unix-ID.
+ * For now this is for the default idmap domain only.
+ * Should be extended later on.
+ */
+NTSTATUS idmap_tdb_common_get_new_id(struct idmap_domain *dom,
+				     struct unixid *id);
+
+/*
+ * store a mapping into the idmap database
+ *
+ * the entries that will be stored are
+ * UID map->xid.id => map->sid and map->sid => UID map->xid.id
+ * or
+ * GID map->xid.id => map->sid and map->sid => GID map->xid.id
+ *
+ * for example
+ * UID 12345 = S-1-5-21-297746067-1479432880-4056370663
+ * S-1-5-21-297746067-1479432880-4056370663 = UID 12345
+ *
+ */
+NTSTATUS idmap_tdb_common_set_mapping(struct idmap_domain *dom,
+				      const struct id_map *map);
+
+/*
+ * Create a new mapping for an unmapped SID, also allocating a new ID.
+ * This should be run inside a transaction.
+ *
+ * TODO:
+ *  Properly integrate this with multi domain idmap config:
+ *  Currently, the allocator is default-config only.
+ */
+NTSTATUS idmap_tdb_common_new_mapping(struct idmap_domain *dom,
+				      struct id_map *map);
+
+/*
+ * default multiple id to sid lookup function
+ *
+ * will call idmap_tdb_common_unixid_to_sid for each mapping
+ * if no other function to lookup unixid_to_sid was given in
+ * idmap_tdb_common_context
+ */
+NTSTATUS idmap_tdb_common_unixids_to_sids(struct idmap_domain *dom,
+					  struct id_map **ids);
+
+/*
+ * default single id to sid lookup function
+ *
+ * will read the entries written by idmap_tdb_common_set_mapping
+ */
+NTSTATUS idmap_tdb_common_unixid_to_sid(struct idmap_domain *dom,
+					struct id_map *map);
+
+/**********************************
+ Single sid to id lookup function.
+**********************************/
+
+NTSTATUS idmap_tdb_common_sid_to_unixid(struct idmap_domain *dom,
+					struct id_map *map);
+
+NTSTATUS idmap_tdb_common_sids_to_unixids(struct idmap_domain *dom,
+					  struct id_map **ids);
+
+#endif				/* _IDMAP_TDB_COMMON_H_ */
diff --git a/source3/winbindd/wscript_build b/source3/winbindd/wscript_build
index 071069b535..07241e4982 100644
--- a/source3/winbindd/wscript_build
+++ b/source3/winbindd/wscript_build
@@ -20,7 +20,7 @@ IDMAP_ADEX_SRC = '''idmap_adex/idmap_adex.c
 IDMAP_AUTORID_SRC = '''idmap_autorid.c'''
 
 IDMAP_RW_SRC = 'idmap_rw.c'
-IDMAP_SRC = 'idmap.c idmap_util.c ${IDMAP_RW_SRC}'
+IDMAP_SRC = 'idmap.c idmap_util.c idmap_tdb_common.c ${IDMAP_RW_SRC}'
 
 bld.SAMBA3_LIBRARY('idmap',
                    source=IDMAP_SRC,