This commit was manufactured by cvs2svn to create branch 'SAMBA_3_0'.

docs/docbook/projdoc/StandAloneServer.xml

@@ -0,0 +1,47 @@
+<chapter id="StandAloneServer">
+<chapterinfo>
+	&author.jht;
+</chapterinfo>
+<title>Stand-Alone Servers</title>
+
+<sect1>
+<title>Stand Alone Server</title>
+
+<para>
+The term <emphasis>stand alone server</emphasis> means that the server
+will provide local authentication and access control for all resources
+that are available from it. In general this means that there will be a
+local user database. In more technical terms, it means that resources
+on the machine will either be made available in either SHARE mode or in
+USER mode. SHARE mode and USER mode security are documented under
+discussions regarding "security mode". The smb.conf configuration parameters
+that control security mode are: "security = user" and "security = share".
+</para>
+
+<para>
+No special action is needed other than to create user accounts. Stand-alone
+servers do NOT provide network logon services, meaning that machines that
+use this server do NOT perform a domain logon but instead make use only of
+the MS Windows logon which is local to the MS Windows workstation/server.
+</para>
+
+<para>
+Samba tends to blur the distinction a little in respect of what is
+a stand alone server. This is because the authentication database may be
+local or on a remote server, even if from the samba protocol perspective
+the samba server is NOT a member of a domain security context.
+</para>
+
+<para>
+Through the use of PAM (Pluggable Authentication Modules) and nsswitch
+(the name service switcher) the source of authentication may reside on 
+another server. We would be inclined to call this the authentication server.
+This means that the samba server may use the local Unix/Linux system
+password database (/etc/passwd or /etc/shadow), may use a local smbpasswd
+file (/etc/samba/smbpasswd or /usr/local/samba/lib/private/smbpasswd), or
+may use an LDAP back end, or even via PAM and Winbind another CIFS/SMB
+server for authentication.
+</para>
+
+</sect1>
+</chapter>

source/nsswitch/winbindd_passdb.c

@@ -0,0 +1,360 @@
+/* 
+   Unix SMB/CIFS implementation.
+
+   Winbind rpc backend functions
+
+   Copyright (C) Tim Potter 2000-2001,2003
+   Copyright (C) Simo Sorce 2003
+   
+   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 "winbindd.h"
+
+#undef DBGC_CLASS
+#define DBGC_CLASS DBGC_WINBIND
+
+
+/* Query display info for a domain.  This returns enough information plus a
+   bit extra to give an overview of domain users for the User Manager
+   application. */
+static NTSTATUS query_user_list(struct winbindd_domain *domain,
+			       TALLOC_CTX *mem_ctx,
+			       uint32 *num_entries, 
+			       WINBIND_USERINFO **info)
+{
+	SAM_ACCOUNT *sam_account = NULL;
+	NTSTATUS result;
+	uint32 i;
+
+	DEBUG(3,("pdb: query_user_list\n"));
+
+	if (NT_STATUS_IS_ERR(result = pdb_init_sam(&sam_account))) {
+		return result;
+	}
+
+	i = 0;
+	*info = NULL;
+	
+	if (pdb_setsampwent(False)) {
+	
+		while (pdb_getsampwent(sam_account)) {
+		
+			/* we return only nua accounts, or we will have duplicates */
+			if (!idmap_check_sid_is_in_free_range(pdb_get_user_sid(sam_account))) {
+				continue;
+			}
+
+			*info = talloc_realloc(mem_ctx, *info, (i + 1) * sizeof(WINBIND_USERINFO));
+			if (!(*info)) {
+				DEBUG(0,("query_user_list: out of memory!\n"));
+				result = NT_STATUS_NO_MEMORY;
+				break;
+			}
+
+			(*info)[i].user_sid = talloc(mem_ctx, sizeof(DOM_SID));
+			(*info)[i].group_sid = talloc(mem_ctx, sizeof(DOM_SID));
+			if (!((*info)[i].user_sid) || !((*info)[i].group_sid)) {
+				DEBUG(0,("query_user_list: out of memory!\n"));
+				result = NT_STATUS_NO_MEMORY;
+				break;
+			}
+			sid_copy((*info)[i].user_sid, pdb_get_user_sid(sam_account));
+			sid_copy((*info)[i].group_sid, pdb_get_group_sid(sam_account));
+
+			(*info)[i].acct_name = talloc_strdup(mem_ctx, pdb_get_username(sam_account));
+			(*info)[i].full_name = talloc_strdup(mem_ctx, pdb_get_fullname(sam_account));
+			if (!((*info)[i].acct_name) || !((*info)[i].full_name)) {
+				DEBUG(0,("query_user_list: out of memory!\n"));
+				result = NT_STATUS_NO_MEMORY;
+				break;
+			}
+
+			i++;
+
+			if (NT_STATUS_IS_ERR(pdb_reset_sam(sam_account))) {
+				result = NT_STATUS_UNSUCCESSFUL;
+				break;
+			}
+		}
+
+		*num_entries = i;
+		result = NT_STATUS_OK;
+	
+	} else {
+		result = NT_STATUS_UNSUCCESSFUL;
+	}
+
+	pdb_free_sam(&sam_account);
+	return result;
+}
+
+/* list all domain groups */
+static NTSTATUS enum_dom_groups(struct winbindd_domain *domain,
+				TALLOC_CTX *mem_ctx,
+				uint32 *num_entries, 
+				struct acct_info **info)
+{
+	NTSTATUS result = NT_STATUS_OK;
+
+	DEBUG(3,("pdb: enum_dom_groups (group support not implemented)\n"));
+
+	*num_entries = 0;
+	*info = 0;
+
+	return result;	
+}
+
+/* List all domain groups */
+
+static NTSTATUS enum_local_groups(struct winbindd_domain *domain,
+				TALLOC_CTX *mem_ctx,
+				uint32 *num_entries, 
+				struct acct_info **info)
+{
+	NTSTATUS result = NT_STATUS_OK;
+
+	DEBUG(3,("pdb: enum_local_groups (group support not implemented)\n"));
+
+	*num_entries = 0;
+	*info = 0;
+
+	return result;	
+}
+
+/* convert a single name to a sid in a domain */
+static NTSTATUS name_to_sid(struct winbindd_domain *domain,
+			    TALLOC_CTX *mem_ctx,
+			    const char *name,
+			    DOM_SID *sid,
+			    enum SID_NAME_USE *type)
+{
+	SAM_ACCOUNT *sam_account = NULL;
+	NTSTATUS result = NT_STATUS_UNSUCCESSFUL;
+
+	DEBUG(3,("pdb: name_to_sid name=%s (group support not implemented)\n", name));
+
+	if (NT_STATUS_IS_OK(pdb_init_sam(&sam_account))) {
+		if (!pdb_getsampwnam(sam_account, name)) {
+			result = NT_STATUS_UNSUCCESSFUL;
+	 	} else { /* it is a sam user */
+			sid_copy(sid, pdb_get_user_sid(sam_account));
+			*type = SID_NAME_USER;
+			result = NT_STATUS_OK;
+		}
+	}
+
+	pdb_free_sam(&sam_account);
+	return result;	
+}
+
+/*
+  convert a domain SID to a user or group name
+*/
+static NTSTATUS sid_to_name(struct winbindd_domain *domain,
+			    TALLOC_CTX *mem_ctx,
+			    DOM_SID *sid,
+			    char **name,
+			    enum SID_NAME_USE *type)
+{
+	SAM_ACCOUNT *sam_account = NULL;
+	NTSTATUS result = NT_STATUS_UNSUCCESSFUL;
+	uint32 id;
+
+	DEBUG(3,("pdb: sid_to_name sid=%s\n", sid_string_static(sid)));
+
+	if (NT_STATUS_IS_OK(sid_to_uid(sid, &id))) { /* this is a user */
+
+		if (NT_STATUS_IS_ERR(result = pdb_init_sam(&sam_account))) {
+			return result;
+		}
+	
+		if (!pdb_getsampwsid(sam_account, sid)) {
+			pdb_free_sam(&sam_account);
+			return NT_STATUS_UNSUCCESSFUL;
+ 		}
+	
+		*name = talloc_strdup(mem_ctx, pdb_get_username(sam_account));	
+		if (!(*name)) {
+			DEBUG(0,("query_user: out of memory!\n"));
+			pdb_free_sam(&sam_account);
+			return NT_STATUS_NO_MEMORY;
+		}
+
+		pdb_free_sam(&sam_account);
+		*type = SID_NAME_USER;
+		result = NT_STATUS_OK;
+
+	} else if (NT_STATUS_IS_OK(sid_to_gid(sid, &id))) { /* this is a group */
+		
+		DEBUG(3,("pdb: sid_to_name: group support not implemented\n"));
+		result = NT_STATUS_UNSUCCESSFUL;
+	}
+
+	return result;
+}
+
+/* Lookup user information from a rid or username. */
+static NTSTATUS query_user(struct winbindd_domain *domain, 
+			   TALLOC_CTX *mem_ctx, 
+			   DOM_SID *user_sid, 
+			   WINBIND_USERINFO *user_info)
+{
+	SAM_ACCOUNT *sam_account = NULL;
+	NTSTATUS result;
+
+	DEBUG(3,("pdb: query_user sid=%s\n", sid_string_static(user_sid)));
+
+	if (NT_STATUS_IS_ERR(result = pdb_init_sam(&sam_account))) {
+		return result;
+	}
+	
+	if (!pdb_getsampwsid(sam_account, user_sid)) {
+		pdb_free_sam(&sam_account);
+		return NT_STATUS_UNSUCCESSFUL;
+ 	}
+
+	/* we return only nua accounts, or we will have duplicates */
+	if (!idmap_check_sid_is_in_free_range(user_sid)) {
+		pdb_free_sam(&sam_account);
+		return NT_STATUS_UNSUCCESSFUL;
+	}
+
+	user_info->user_sid = talloc(mem_ctx, sizeof(DOM_SID));
+	user_info->group_sid = talloc(mem_ctx, sizeof(DOM_SID));
+	if (!(user_info->user_sid) || !(user_info->group_sid)) {
+		DEBUG(0,("query_user: out of memory!\n"));
+		pdb_free_sam(&sam_account);
+		return NT_STATUS_NO_MEMORY;
+	}
+	sid_copy(user_info->user_sid, pdb_get_user_sid(sam_account));
+	sid_copy(user_info->group_sid, pdb_get_group_sid(sam_account));
+
+	user_info->acct_name = talloc_strdup(mem_ctx, pdb_get_username(sam_account));
+	user_info->full_name = talloc_strdup(mem_ctx, pdb_get_fullname(sam_account));
+	if (!(user_info->acct_name) || !(user_info->full_name)) {
+		DEBUG(0,("query_user: out of memory!\n"));
+		pdb_free_sam(&sam_account);
+		return NT_STATUS_NO_MEMORY;
+	}
+
+	pdb_free_sam(&sam_account);
+	return NT_STATUS_OK;
+}                                   
+
+/* Lookup groups a user is a member of.  I wish Unix had a call like this! */
+static NTSTATUS lookup_usergroups(struct winbindd_domain *domain,
+				  TALLOC_CTX *mem_ctx,
+				  DOM_SID *user_sid,
+				  uint32 *num_groups, DOM_SID ***user_gids)
+{
+	NTSTATUS result = NT_STATUS_OK;
+
+	DEBUG(3,("pdb: lookup_usergroups (group support not implemented)\n"));
+
+	num_groups = 0;
+	user_gids = 0;
+
+	return result;
+}
+
+
+/* Lookup group membership given a rid.   */
+static NTSTATUS lookup_groupmem(struct winbindd_domain *domain,
+				TALLOC_CTX *mem_ctx,
+				DOM_SID *group_sid, uint32 *num_names, 
+				DOM_SID ***sid_mem, char ***names, 
+				uint32 **name_types)
+{
+        NTSTATUS result = NT_STATUS_NOT_IMPLEMENTED;
+
+	DEBUG(3,("pdb: lookup_groupmem (group support not implemented)\n"));
+
+	num_names = 0;
+	sid_mem = 0;
+	names = 0;
+	name_types = 0;
+
+        return result;
+}
+
+/* find the sequence number for a domain */
+static NTSTATUS sequence_number(struct winbindd_domain *domain, uint32 *seq)
+{
+	/* FIXME: we fake up the seq_num untill our passdb support it */
+	static uint32 seq_num;
+
+	DEBUG(3,("pdb: sequence_number\n"));
+
+	*seq = seq_num++;
+
+	return NT_STATUS_OK;
+}
+
+/* get a list of trusted domains */
+static NTSTATUS trusted_domains(struct winbindd_domain *domain,
+				TALLOC_CTX *mem_ctx,
+				uint32 *num_domains,
+				char ***names,
+				char ***alt_names,
+				DOM_SID **dom_sids)
+{
+	NTSTATUS result = NT_STATUS_NOT_IMPLEMENTED;
+
+	DEBUG(3,("pdb: trusted_domains (todo!)\n"));
+
+	return result;
+}
+
+/* find the domain sid for a domain */
+static NTSTATUS domain_sid(struct winbindd_domain *domain, DOM_SID *sid)
+{
+	DEBUG(3,("pdb: domain_sid\n"));
+
+	if (strcmp(domain->name, lp_workgroup())) {
+		return NT_STATUS_INVALID_PARAMETER;
+	} else {
+		sid_copy(sid, get_global_sam_sid());
+		return NT_STATUS_OK;
+	}
+}
+
+/* find alternate names list for the domain 
+ * should we look for netbios aliases?? 
+				SSS	*/
+static NTSTATUS alternate_name(struct winbindd_domain *domain)
+{
+	DEBUG(3,("pdb: alternate_name\n"));
+
+	return NT_STATUS_OK;
+}
+
+
+/* the rpc backend methods are exposed via this structure */
+struct winbindd_methods passdb_methods = {
+	False,
+	query_user_list,
+	enum_dom_groups,
+	enum_local_groups,
+	name_to_sid,
+	sid_to_name,
+	query_user,
+	lookup_usergroups,
+	lookup_groupmem,
+	sequence_number,
+	trusted_domains,
+	domain_sid,
+	alternate_name
+};

source/sam/idmap_util.c

@@ -0,0 +1,377 @@
+/* 
+   Unix SMB/CIFS implementation.
+   ID Mapping
+   Copyright (C) Simo Sorce 2003
+
+   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"
+
+#undef DBGC_CLASS
+#define DBGC_CLASS DBGC_IDMAP
+
+
+/******************************************************************
+ * Get the free RID base if idmap is configured, otherwise return 0
+ ******************************************************************/
+
+uint32 idmap_get_free_rid_base(void)
+{
+	uint32 low, high;
+	if (idmap_get_free_rid_range(&low, &high)) {
+		return low;
+	}
+	return 0;
+}
+
+BOOL idmap_check_ugid_is_in_free_range(uint32 id)
+{
+	uint32 low, high;
+
+	if (!idmap_get_free_ugid_range(&low, &high)) {
+		return False;
+	}
+	if (id < low || id > high) {
+		return False;
+	}
+	return True;
+}
+
+BOOL idmap_check_rid_is_in_free_range(uint32 rid)
+{
+	uint32 low, high;
+
+	if (!idmap_get_free_rid_range(&low, &high)) {
+		return False;
+	}
+	if (rid < low || rid > high) {
+		return False;
+	}
+	return True;
+}
+
+/* if it is a foreign SID or if the SID is in the free range, return true */
+
+BOOL idmap_check_sid_is_in_free_range(const DOM_SID *sid)
+{
+	if (sid_compare_domain(get_global_sam_sid(), sid) == 0) {
+	
+		uint32 rid;
+
+		if (sid_peek_rid(sid, &rid)) {
+			return idmap_check_rid_is_in_free_range(rid);
+		}
+
+		return False;
+	}
+
+	return True;
+}
+
+/******************************************************************
+ * Get the the non-algorithmic RID range if idmap range are defined
+ ******************************************************************/
+
+BOOL idmap_get_free_rid_range(uint32 *low, uint32 *high)
+{
+	uint32 id_low, id_high;
+
+	if (lp_idmap_only()) {
+		*low = BASE_RID;
+		*high = (uint32)-1;
+	}
+
+	if (!idmap_get_free_ugid_range(&id_low, &id_high)) {
+		return False;
+	}
+
+	*low = fallback_pdb_uid_to_user_rid(id_low);
+	if (fallback_pdb_user_rid_to_uid((uint32)-1) < id_high) {
+		*high = (uint32)-1;
+	} else {
+		*high = fallback_pdb_uid_to_user_rid(id_high);
+	}
+
+	return True;
+}
+
+BOOL idmap_get_free_ugid_range(uint32 *low, uint32 *high)
+{
+	uid_t u_low, u_high;
+	gid_t g_low, g_high;
+
+	if (!lp_idmap_uid(&u_low, &u_high) || !lp_idmap_gid(&g_low, &g_high)) {
+		return False;
+	}
+	if (u_low < g_low) {
+		*low = u_low;
+	} else {
+		*low = g_low;
+	}
+	if (u_high < g_high) {
+		*high = g_high;
+	} else {
+		*high = u_high;
+	}
+	return True;
+}
+
+/*****************************************************************
+ *THE CANONICAL* convert uid_t to SID function.
+ check idmap if uid is in idmap range, otherwise falls back to
+ the legacy algorithmic mapping.
+ A special cache is used for uids that maps to Wellknown SIDs
+ Returns SID pointer.
+*****************************************************************/  
+
+NTSTATUS uid_to_sid(DOM_SID *sid, uid_t uid)
+{
+	NTSTATUS ret = NT_STATUS_UNSUCCESSFUL;
+	unid_t id;
+	int flags;
+
+	DEBUG(10,("uid_to_sid: uid = [%d]\n", uid));
+
+	flags = ID_USERID;
+	if (!lp_idmap_only() && !idmap_check_ugid_is_in_free_range(uid)) {
+		flags |= ID_NOMAP;
+	}
+
+	id.uid = uid;
+	if (NT_STATUS_IS_ERR(ret = idmap_get_sid_from_id(sid, id, flags))) {
+		DEBUG(10, ("uid_to_sid: Failed to map uid = [%u]\n", (unsigned int)uid));
+		if (flags & ID_NOMAP) {
+			sid_copy(sid, get_global_sam_sid());
+			sid_append_rid(sid, fallback_pdb_uid_to_user_rid(uid));
+
+			DEBUG(10,("uid_to_sid: Fall back to algorithmic mapping: %u -> %s\n", (unsigned int)uid, sid_string_static(sid)));
+			ret = NT_STATUS_OK;
+		}
+	}
+
+	return ret;
+}
+
+/*****************************************************************
+ *THE CANONICAL* convert gid_t to SID function.
+ check idmap if gid is in idmap range, otherwise falls back to
+ the legacy algorithmic mapping.
+ Group mapping is used for gids that maps to Wellknown SIDs
+ Returns SID pointer.
+*****************************************************************/  
+
+NTSTATUS gid_to_sid(DOM_SID *sid, gid_t gid)
+{
+	NTSTATUS ret = NT_STATUS_UNSUCCESSFUL;
+	GROUP_MAP map;
+	unid_t id;
+	int flags;
+
+	DEBUG(10,("gid_to_sid: gid = [%d]\n", gid));
+
+	flags = ID_GROUPID;
+	if (!lp_idmap_only() && !idmap_check_ugid_is_in_free_range(gid)) {
+		flags |= ID_NOMAP;
+	}
+
+	id.gid = gid;
+	if (NT_STATUS_IS_ERR(ret = idmap_get_sid_from_id(sid, id, flags))) {
+		DEBUG(10, ("gid_to_sid: Failed to map gid = [%u]\n", (unsigned int)gid));
+		if (flags & ID_NOMAP) {
+			sid_copy(sid, get_global_sam_sid());
+			sid_append_rid(sid, pdb_gid_to_group_rid(gid));
+
+			DEBUG(10,("gid_to_sid: Fall back to algorithmic mapping: %u -> %s\n", (unsigned int)gid, sid_string_static(sid)));
+			ret = NT_STATUS_OK;
+		}
+	}
+
+	return ret;
+}
+
+/*****************************************************************
+ *THE CANONICAL* convert SID to uid function.
+ if it is a foreign sid or it is in idmap rid range check idmap,
+ otherwise falls back to the legacy algorithmic mapping.
+ A special cache is used for uids that maps to Wellknown SIDs
+ Returns True if this name is a user sid and the conversion
+ was done correctly, False if not.
+*****************************************************************/  
+
+NTSTATUS sid_to_uid(const DOM_SID *sid, uid_t *uid)
+{
+	NTSTATUS ret = NT_STATUS_UNSUCCESSFUL;
+	BOOL fallback = False;
+	unid_t id;
+	int flags;
+
+	DEBUG(10,("sid_to_uid: sid = [%s]\n", sid_string_static(sid)));
+
+	flags = ID_USERID;
+	if (!lp_idmap_only()) {
+		if (!idmap_check_sid_is_in_free_range(sid)) {
+			flags |= ID_NOMAP;
+			fallback = True;
+		}
+	}
+
+	if (NT_STATUS_IS_OK(idmap_get_id_from_sid(&id, &flags, sid))) {
+
+		DEBUG(10,("sid_to_uid: uid = [%d]\n", id.uid));
+
+		*uid = id.uid;
+		ret = NT_STATUS_OK;
+		
+	} else if (fallback) {
+		uint32 rid;
+
+		if (!sid_peek_rid(sid, &rid)) {
+			DEBUG(10,("sid_to_uid: invalid SID!\n"));
+			ret = NT_STATUS_INVALID_PARAMETER;
+			goto done;
+		}
+
+		DEBUG(10,("sid_to_uid: Fall back to algorithmic mapping\n"));
+
+		if (!fallback_pdb_rid_is_user(rid)) {
+			DEBUG(3, ("sid_to_uid: SID %s is *NOT* a user\n", sid_string_static(sid)));
+			ret = NT_STATUS_UNSUCCESSFUL;
+		} else {
+			*uid = fallback_pdb_user_rid_to_uid(rid);
+			DEBUG(10,("sid_to_uid: mapping: %s -> %u\n", sid_string_static(sid), (unsigned int)(*uid)));
+			ret = NT_STATUS_OK;
+		}
+	}
+
+done:
+	return ret;
+}
+
+/*****************************************************************
+ *THE CANONICAL* convert SID to gid function.
+ if it is a foreign sid or it is in idmap rid range check idmap,
+ otherwise falls back to the legacy algorithmic mapping.
+ Group mapping is used for gids that maps to Wellknown SIDs
+ Returns True if this name is a user sid and the conversion
+ was done correctly, False if not.
+*****************************************************************/  
+
+NTSTATUS sid_to_gid(const DOM_SID *sid, gid_t *gid)
+{
+	NTSTATUS ret = NT_STATUS_UNSUCCESSFUL;
+	BOOL fallback = False;
+	uint32 rid;
+	unid_t id;
+	int flags;
+
+	DEBUG(10,("sid_to_gid: sid = [%s]\n", sid_string_static(sid)));
+
+	flags = ID_GROUPID;
+	if (!lp_idmap_only()) {
+		if (!idmap_check_sid_is_in_free_range(sid)) {
+			flags |= ID_NOMAP;
+			fallback = True;
+		}
+	}
+
+	if (NT_STATUS_IS_OK(idmap_get_id_from_sid(&id, &flags, sid))) {
+		
+		DEBUG(10,("sid_to_gid: gid = [%d]\n", id.gid));
+		*gid = id.gid;
+		ret = NT_STATUS_OK;
+
+	} else if (fallback) {
+		uint32 rid;
+
+		if (!sid_peek_rid(sid, &rid)) {
+			DEBUG(10,("sid_to_uid: invalid SID!\n"));
+			ret = NT_STATUS_INVALID_PARAMETER;
+			goto done;
+		}
+
+		DEBUG(10,("sid_to_gid: Fall back to algorithmic mapping\n"));
+
+		if (fallback_pdb_rid_is_user(rid)) {
+			DEBUG(3, ("sid_to_gid: SID %s is *NOT* a group\n", sid_string_static(sid)));
+			ret = NT_STATUS_UNSUCCESSFUL;
+		} else {
+			*gid = pdb_group_rid_to_gid(rid);
+			DEBUG(10,("sid_to_gid: mapping: %s -> %u\n", sid_string_static(sid), (unsigned int)(*gid)));
+			ret = NT_STATUS_OK;
+		}
+	}
+
+done:
+	return ret;
+}
+
+/* Initialize idmap withWellknown SIDs like Guest, that are necessary
+ * to make samba run properly */
+BOOL idmap_init_wellknown_sids(void)
+{
+	const char *guest_account = lp_guestaccount();
+	struct passwd *pass;
+	GROUP_MAP *map=NULL;
+	int num_entries=0;
+	DOM_SID sid;
+	unid_t id;
+	int flags;
+
+	if (!(guest_account && *guest_account)) {
+		DEBUG(1, ("NULL guest account!?!?\n"));
+		return False;
+	}
+
+	pass = getpwnam_alloc(guest_account);
+	if (!pass) {
+		return False;
+	}
+
+	flags = ID_USERID;
+	id.uid = pass->pw_uid;
+	sid_copy(&sid, get_global_sam_sid());
+	sid_append_rid(&sid, DOMAIN_USER_RID_GUEST);
+	if (NT_STATUS_IS_ERR(idmap_set_mapping(&sid, id, flags))) {
+		passwd_free(&pass);
+		return False;
+	}
+
+	/* now fill in group mappings */
+	if(pdb_enum_group_mapping(SID_NAME_UNKNOWN, &map, &num_entries, ENUM_ONLY_MAPPED, MAPPING_WITHOUT_PRIV)) {
+		int i;
+
+		for (i = 0; i < num_entries; i++) {
+			id.gid = map[i].gid;
+			idmap_set_mapping(&(map[i].sid), id, ID_GROUPID);
+		}
+	}
+
+	/* check if DOMAIN_GROUP_RID_GUESTS SID is set, if not store the
+	 * guest account gid as mapping */
+	flags = ID_GROUPID | ID_NOMAP;
+	sid_copy(&sid, get_global_sam_sid());
+	sid_append_rid(&sid, DOMAIN_GROUP_RID_GUESTS);
+	if (NT_STATUS_IS_ERR(idmap_get_id_from_sid(&id, &flags, &sid))) {
+		flags = ID_GROUPID;
+		id.gid = pass->pw_gid;
+		if (NT_STATUS_IS_ERR(idmap_set_mapping(&sid, id, flags))) {
+			passwd_free(&pass);
+			return False;
+		}
+	}
+
+	passwd_free(&pass);
+	return True;
+}