r4096: move the samdb code to source/dsdb/

the idea is to have a directory service db layer
which will be used by the ldap server, samr server, drsuapi server
authentification...

I plan to make different implementations of this interface possible
- current default will be the current samdb code with sam.ldb
- a compat implementation for samba3 (if someone wants to write one)
- a new dsdb implementation which:
  - understands naming contexts (directory parrtitions)
  - do schema and acl checking checking
  - maintain objectGUID, timestamps and USN number,
    maybe linked attributes ('member' and 'memberOf' attributes)
  - store metadata on a attribute=value combination...

metze
(This used to be commit 893a8b8bca2f020fbbe6f469aaa8dd4478249eb8)

2 files changed, 1029 insertions, 0 deletions

diff --git a/source4/dsdb/common/flag_mapping.c b/source4/dsdb/common/flag_mapping.c
new file mode 100644
index 0000000000..30c5b0cf13
--- /dev/null
+++ b/source4/dsdb/common/flag_mapping.c
@@ -0,0 +1,135 @@
+/* 
+   Unix SMB/CIFS implementation.
+   helper mapping functions for the SAMDB server
+   
+   Copyright (C) Stefan (metze) Metzmacher 2002
+   Copyright (C) Andrew Tridgell 2004
+  
+   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 "librpc/gen_ndr/ndr_samr.h"
+
+/* 
+translated the ACB_CTRL Flags to UserFlags (userAccountControl) 
+*/ 
+/* mapping between ADS userAccountControl and SAMR acct_flags */
+static const struct {
+	uint32_t uf;
+	uint16_t acb;
+} acct_flags_map[] = {
+	{ UF_ACCOUNTDISABLE, ACB_DISABLED },
+	{ UF_HOMEDIR_REQUIRED, ACB_HOMDIRREQ },
+	{ UF_PASSWD_NOTREQD, ACB_PWNOTREQ },
+	{ UF_TEMP_DUPLICATE_ACCOUNT, ACB_TEMPDUP },
+	{ UF_NORMAL_ACCOUNT, ACB_NORMAL },
+	{ UF_MNS_LOGON_ACCOUNT, ACB_MNS },
+	{ UF_INTERDOMAIN_TRUST_ACCOUNT, ACB_DOMTRUST },
+	{ UF_WORKSTATION_TRUST_ACCOUNT, ACB_WSTRUST },
+	{ UF_SERVER_TRUST_ACCOUNT, ACB_SVRTRUST },
+	{ UF_DONT_EXPIRE_PASSWD, ACB_PWNOEXP },
+	{ UF_LOCKOUT, ACB_AUTOLOCK }
+};
+
+uint32_t samdb_acb2uf(uint16_t acb)
+{
+	uint32_t i, ret = 0;
+	for (i=0;i<ARRAY_SIZE(acct_flags_map);i++) {
+		if (acct_flags_map[i].acb & acb) {
+			ret |= acct_flags_map[i].uf;
+		}
+	}
+	return ret;
+}
+
+/*
+translated the UserFlags (userAccountControl) to ACB_CTRL Flags
+*/
+uint16_t samdb_uf2acb(uint32_t uf)
+{
+	uint32_t i;
+	uint16_t ret = 0;
+	for (i=0;i<ARRAY_SIZE(acct_flags_map);i++) {
+		if (acct_flags_map[i].uf & uf) {
+			ret |= acct_flags_map[i].acb;
+		}
+	}
+	return ret;
+}
+
+/* 
+get the accountType from the UserFlags
+*/
+uint32_t samdb_uf2atype(uint32_t uf)
+{
+	uint32_t atype = 0x00000000;
+		
+	if (uf & UF_NORMAL_ACCOUNT)			atype = ATYPE_NORMAL_ACCOUNT;
+	else if (uf & UF_TEMP_DUPLICATE_ACCOUNT)	atype = ATYPE_NORMAL_ACCOUNT;
+	else if (uf & UF_SERVER_TRUST_ACCOUNT)		atype = ATYPE_WORKSTATION_TRUST;
+	else if (uf & UF_WORKSTATION_TRUST_ACCOUNT)	atype = ATYPE_WORKSTATION_TRUST;
+	else if (uf & UF_INTERDOMAIN_TRUST_ACCOUNT)	atype = ATYPE_INTERDOMAIN_TRUST;
+
+	return atype;
+} 
+
+/* 
+get the accountType from the groupType
+*/
+uint32_t samdb_gtype2atype(uint32_t gtype)
+{
+	uint32_t atype = 0x00000000;
+	
+	switch(gtype) {
+		case GTYPE_SECURITY_BUILTIN_LOCAL_GROUP:
+			atype = ATYPE_SECURITY_LOCAL_GROUP;
+			break;
+		case GTYPE_SECURITY_DOMAIN_LOCAL_GROUP:
+			atype = ATYPE_SECURITY_LOCAL_GROUP;
+			break;
+		case GTYPE_SECURITY_GLOBAL_GROUP:
+			atype = ATYPE_SECURITY_GLOBAL_GROUP;
+			break;
+	
+		case GTYPE_DISTRIBUTION_GLOBAL_GROUP:
+			atype = ATYPE_DISTRIBUTION_GLOBAL_GROUP;
+			break;
+		case GTYPE_DISTRIBUTION_DOMAIN_LOCAL_GROUP:
+			atype = ATYPE_DISTRIBUTION_UNIVERSAL_GROUP;
+			break;
+		case GTYPE_DISTRIBUTION_UNIVERSAL_GROUP:
+			atype = ATYPE_DISTRIBUTION_LOCAL_GROUP;
+			break;
+	}
+
+	return atype;
+}
+
+/* turn a sAMAccountType into a SID_NAME_USE */
+enum samr_SidType samdb_atype_map(uint32_t atype)
+{
+	switch (atype & 0xF0000000) {
+	case ATYPE_GLOBAL_GROUP:
+		return SID_NAME_DOM_GRP;
+	case ATYPE_SECURITY_LOCAL_GROUP:
+		return SID_NAME_ALIAS;
+	case ATYPE_ACCOUNT:
+		return SID_NAME_USER;
+	default:
+		DEBUG(1,("hmm, need to map account type 0x%x\n", atype));
+	}
+	return SID_NAME_UNKNOWN;
+}
diff --git a/source4/dsdb/samdb/samdb.c b/source4/dsdb/samdb/samdb.c
new file mode 100644
index 0000000000..7501d94ae6
--- /dev/null
+++ b/source4/dsdb/samdb/samdb.c
@@ -0,0 +1,894 @@
+/* 
+   Unix SMB/CIFS implementation.
+
+   interface functions for the sam database
+
+   Copyright (C) Andrew Tridgell 2004
+   
+   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 "librpc/gen_ndr/ndr_netlogon.h"
+#include "lib/ldb/include/ldb.h"
+
+/*
+  connect to the SAM database
+  return an opaque context pointer on success, or NULL on failure
+ */
+void *samdb_connect(TALLOC_CTX *mem_ctx)
+{
+	return ldb_wrap_connect(mem_ctx, lp_sam_url(), 0, NULL);
+}
+
+/*
+  search the sam for the specified attributes - varargs variant
+*/
+int samdb_search(void *ctx,
+		 TALLOC_CTX *mem_ctx, 
+		 const char *basedn,
+		 struct ldb_message ***res,
+		 const char * const *attrs,
+		 const char *format, ...) _PRINTF_ATTRIBUTE(6,7)
+{
+	struct ldb_wrap *sam_ctx = ctx;
+	va_list ap;
+	int count;
+
+	va_start(ap, format);
+	count = gendb_search_v(sam_ctx->ldb, mem_ctx, basedn, res, attrs, format, ap);
+	va_end(ap);
+
+	return count;
+}
+
+/*
+  free up a search result
+*/
+int samdb_search_free(void *ctx,
+		      TALLOC_CTX *mem_ctx, struct ldb_message **res)
+{
+	struct ldb_wrap *sam_ctx = ctx;
+	ldb_set_alloc(sam_ctx->ldb, talloc_realloc_fn, mem_ctx);
+	return ldb_search_free(sam_ctx->ldb, res);
+}
+
+/*
+  search the sam for a single string attribute in exactly 1 record
+*/
+const char *samdb_search_string_v(void *ctx,
+				  TALLOC_CTX *mem_ctx,
+				  const char *basedn,
+				  const char *attr_name,
+				  const char *format, va_list ap) _PRINTF_ATTRIBUTE(5,0)
+{
+	struct ldb_wrap *sam_ctx = ctx;
+	int count;
+	const char * const attrs[2] = { attr_name, NULL };
+	struct ldb_message **res = NULL;
+
+	count = gendb_search_v(sam_ctx->ldb, mem_ctx, basedn, &res, attrs, format, ap);
+	if (count > 1) {		
+		DEBUG(1,("samdb: search for %s %s not single valued (count=%d)\n", 
+			 attr_name, format, count));
+	}
+	if (count != 1) {
+		samdb_search_free(ctx, mem_ctx, res);
+		return NULL;
+	}
+
+	return samdb_result_string(res[0], attr_name, NULL);
+}
+				 
+
+/*
+  search the sam for a single string attribute in exactly 1 record
+*/
+const char *samdb_search_string(void *ctx,
+				TALLOC_CTX *mem_ctx,
+				const char *basedn,
+				const char *attr_name,
+				const char *format, ...) _PRINTF_ATTRIBUTE(5,6)
+{
+	va_list ap;
+	const char *str;
+
+	va_start(ap, format);
+	str = samdb_search_string_v(ctx, mem_ctx, basedn, attr_name, format, ap);
+	va_end(ap);
+
+	return str;
+}
+
+/*
+  return the count of the number of records in the sam matching the query
+*/
+int samdb_search_count(void *ctx,
+		       TALLOC_CTX *mem_ctx,
+		       const char *basedn,
+		       const char *format, ...) _PRINTF_ATTRIBUTE(4,5)
+{
+	struct ldb_wrap *samdb_ctx = ctx;
+	va_list ap;
+	struct ldb_message **res;
+	const char * const attrs[] = { NULL };
+	int ret;
+
+	va_start(ap, format);
+	ret = gendb_search_v(samdb_ctx->ldb, mem_ctx, basedn, &res, attrs, format, ap);
+	va_end(ap);
+
+	return ret;
+}
+
+
+/*
+  search the sam for a single integer attribute in exactly 1 record
+*/
+uint_t samdb_search_uint(void *ctx,
+			 TALLOC_CTX *mem_ctx,
+			 uint_t default_value,
+			 const char *basedn,
+			 const char *attr_name,
+			 const char *format, ...) _PRINTF_ATTRIBUTE(6,7)
+{
+	struct ldb_wrap *samdb_ctx = ctx;
+	va_list ap;
+	int count;
+	struct ldb_message **res;
+	const char * const attrs[2] = { attr_name, NULL };
+
+	va_start(ap, format);
+	count = gendb_search_v(samdb_ctx->ldb, mem_ctx, basedn, &res, attrs, format, ap);
+	va_end(ap);
+
+	if (count != 1) {
+		return default_value;
+	}
+
+	return samdb_result_uint(res[0], attr_name, default_value);
+}
+
+/*
+  search the sam for a single signed 64 bit integer attribute in exactly 1 record
+*/
+int64_t samdb_search_int64(void *ctx,
+			   TALLOC_CTX *mem_ctx,
+			   int64_t default_value,
+			   const char *basedn,
+			   const char *attr_name,
+			   const char *format, ...) _PRINTF_ATTRIBUTE(6,7)
+{
+	struct ldb_wrap *samdb_ctx = ctx;
+	va_list ap;
+	int count;
+	struct ldb_message **res;
+	const char * const attrs[2] = { attr_name, NULL };
+
+	va_start(ap, format);
+	count = gendb_search_v(samdb_ctx->ldb, mem_ctx, basedn, &res, attrs, format, ap);
+	va_end(ap);
+
+	if (count != 1) {
+		return default_value;
+	}
+
+	return samdb_result_int64(res[0], attr_name, default_value);
+}
+
+/*
+  search the sam for multipe records each giving a single string attribute
+  return the number of matches, or -1 on error
+*/
+int samdb_search_string_multiple(void *ctx,
+				 TALLOC_CTX *mem_ctx,
+				 const char *basedn,
+				 const char ***strs,
+				 const char *attr_name,
+				 const char *format, ...) _PRINTF_ATTRIBUTE(6,7)
+{
+	struct ldb_wrap *samdb_ctx = ctx;
+	va_list ap;
+	int count, i;
+	const char * const attrs[2] = { attr_name, NULL };
+	struct ldb_message **res = NULL;
+
+	va_start(ap, format);
+	count = gendb_search_v(samdb_ctx->ldb, mem_ctx, basedn, &res, attrs, format, ap);
+	va_end(ap);
+
+	if (count <= 0) {
+		return count;
+	}
+
+	/* make sure its single valued */
+	for (i=0;i<count;i++) {
+		if (res[i]->num_elements != 1) {
+			DEBUG(1,("samdb: search for %s %s not single valued\n", 
+				 attr_name, format));
+			samdb_search_free(ctx, mem_ctx, res);
+			return -1;
+		}
+	}
+
+	*strs = talloc_array_p(mem_ctx, const char *, count+1);
+	if (! *strs) {
+		samdb_search_free(ctx, mem_ctx, res);
+		return -1;
+	}
+
+	for (i=0;i<count;i++) {
+		(*strs)[i] = samdb_result_string(res[i], attr_name, NULL);
+	}
+	(*strs)[count] = NULL;
+
+	return count;
+}
+
+/*
+  pull a uint from a result set. 
+*/
+uint_t samdb_result_uint(struct ldb_message *msg, const char *attr, uint_t default_value)
+{
+	return ldb_msg_find_uint(msg, attr, default_value);
+}
+
+/*
+  pull a (signed) int64 from a result set. 
+*/
+int64_t samdb_result_int64(struct ldb_message *msg, const char *attr, int64_t default_value)
+{
+	return ldb_msg_find_int64(msg, attr, default_value);
+}
+
+/*
+  pull a string from a result set. 
+*/
+const char *samdb_result_string(struct ldb_message *msg, const char *attr, 
+				const char *default_value)
+{
+	return ldb_msg_find_string(msg, attr, default_value);
+}
+
+/*
+  pull a rid from a objectSid in a result set. 
+*/
+uint32_t samdb_result_rid_from_sid(TALLOC_CTX *mem_ctx, struct ldb_message *msg, 
+				 const char *attr, uint32_t default_value)
+{
+	struct dom_sid *sid;
+	const char *sidstr = ldb_msg_find_string(msg, attr, NULL);
+	if (!sidstr) return default_value;
+
+	sid = dom_sid_parse_talloc(mem_ctx, sidstr);
+	if (!sid) return default_value;
+
+	return sid->sub_auths[sid->num_auths-1];
+}
+
+/*
+  pull a dom_sid structure from a objectSid in a result set. 
+*/
+struct dom_sid *samdb_result_dom_sid(TALLOC_CTX *mem_ctx, struct ldb_message *msg, 
+				     const char *attr)
+{
+	const char *sidstr = ldb_msg_find_string(msg, attr, NULL);
+	if (!sidstr) return NULL;
+
+	return dom_sid_parse_talloc(mem_ctx, sidstr);
+}
+
+/*
+  pull a guid structure from a objectGUID in a result set. 
+*/
+struct GUID samdb_result_guid(struct ldb_message *msg, const char *attr)
+{
+	NTSTATUS status;
+	struct GUID guid;
+	const char *guidstr = ldb_msg_find_string(msg, attr, NULL);
+
+	ZERO_STRUCT(guid);
+
+	if (!guidstr) return guid;
+
+	status = GUID_from_string(guidstr, &guid);
+	if (!NT_STATUS_IS_OK(status)) {
+		ZERO_STRUCT(guid);
+		return guid;
+	}
+
+	return guid;
+}
+
+/*
+  pull a sid prefix from a objectSid in a result set. 
+  this is used to find the domain sid for a user
+*/
+const char *samdb_result_sid_prefix(TALLOC_CTX *mem_ctx, struct ldb_message *msg, 
+				    const char *attr)
+{
+	struct dom_sid *sid = samdb_result_dom_sid(mem_ctx, msg, attr);
+	if (!sid || sid->num_auths < 1) return NULL;
+
+	sid->num_auths--;
+
+	return dom_sid_string(mem_ctx, sid);
+}
+
+/*
+  pull a NTTIME in a result set. 
+*/
+NTTIME samdb_result_nttime(struct ldb_message *msg, const char *attr, const char *default_value)
+{
+	const char *str = ldb_msg_find_string(msg, attr, default_value);
+	return nttime_from_string(str);
+}
+
+/*
+  pull a uint64_t from a result set. 
+*/
+uint64_t samdb_result_uint64(struct ldb_message *msg, const char *attr, uint64_t default_value)
+{
+	return ldb_msg_find_uint64(msg, attr, default_value);
+}
+
+
+/*
+  construct the allow_password_change field from the PwdLastSet attribute and the 
+  domain password settings
+*/
+NTTIME samdb_result_allow_password_change(void *ctx, TALLOC_CTX *mem_ctx, 
+					  const char *domain_dn, 
+					  struct ldb_message *msg, 
+					  const char *attr)
+{
+	uint64_t attr_time = samdb_result_uint64(msg, attr, 0);
+	int64_t minPwdAge;
+
+	if (attr_time == 0) {
+		return 0;
+	}
+
+	minPwdAge = samdb_search_int64(ctx, mem_ctx, 0, NULL, 
+				       "minPwdAge", "dn=%s", domain_dn);
+
+	/* yes, this is a -= not a += as minPwdAge is stored as the negative
+	   of the number of 100-nano-seconds */
+	attr_time -= minPwdAge;
+
+	return attr_time;
+}
+
+/*
+  construct the force_password_change field from the PwdLastSet attribute and the 
+  domain password settings
+*/
+NTTIME samdb_result_force_password_change(void *ctx, TALLOC_CTX *mem_ctx, 
+					  const char *domain_dn, 
+					  struct ldb_message *msg, 
+					  const char *attr)
+{
+	uint64_t attr_time = samdb_result_uint64(msg, attr, 0);
+	int64_t maxPwdAge;
+
+	if (attr_time == 0) {
+		return 0;
+	}
+
+	maxPwdAge = samdb_search_int64(ctx, mem_ctx, 0, NULL, "maxPwdAge", "dn=%s", domain_dn);
+	if (maxPwdAge == 0) {
+		return 0;
+	} else {
+		attr_time -= maxPwdAge;
+	}
+
+	return attr_time;
+}
+
+/*
+  pull a samr_Password structutre from a result set. 
+*/
+struct samr_Password samdb_result_hash(struct ldb_message *msg, const char *attr)
+{
+	struct samr_Password hash;
+	const struct ldb_val *val = ldb_msg_find_ldb_val(msg, attr);
+	ZERO_STRUCT(hash);
+	if (val) {
+		memcpy(hash.hash, val->data, MIN(val->length, sizeof(hash.hash)));
+	}
+	return hash;
+}
+
+/*
+  pull an array of samr_Password structutres from a result set. 
+*/
+uint_t samdb_result_hashes(TALLOC_CTX *mem_ctx, struct ldb_message *msg, 
+			   const char *attr, struct samr_Password **hashes)
+{
+	uint_t count = 0;
+	const struct ldb_val *val = ldb_msg_find_ldb_val(msg, attr);
+	int i;
+
+	*hashes = NULL;
+	if (!val) {
+		return 0;
+	}
+	count = val->length / 16;
+	if (count == 0) {
+		return 0;
+	}
+
+	*hashes = talloc_array_p(mem_ctx, struct samr_Password, count);
+	if (! *hashes) {
+		return 0;
+	}
+
+	for (i=0;i<count;i++) {
+		memcpy((*hashes)[i].hash, (i*16)+(char *)val->data, 16);
+	}
+
+	return count;
+}
+
+NTSTATUS samdb_result_passwords(TALLOC_CTX *mem_ctx, struct ldb_message *msg, 
+				struct samr_Password **lm_pwd, struct samr_Password **nt_pwd) 
+{
+
+	const char *unicodePwd = samdb_result_string(msg, "unicodePwd", NULL);
+	
+	struct samr_Password *lmPwdHash, *ntPwdHash;
+	if (unicodePwd) {
+		if (nt_pwd) {
+			ntPwdHash = talloc_p(mem_ctx, struct samr_Password);
+			if (!ntPwdHash) {
+				return NT_STATUS_NO_MEMORY;
+			}
+			
+			E_md4hash(unicodePwd, ntPwdHash->hash);
+			*nt_pwd = ntPwdHash;
+		}
+
+		if (lm_pwd) {
+			BOOL lm_hash_ok;
+		
+			lmPwdHash = talloc_p(mem_ctx, struct samr_Password);
+			if (!lmPwdHash) {
+				return NT_STATUS_NO_MEMORY;
+			}
+			
+			/* compute the new nt and lm hashes */
+			lm_hash_ok = E_deshash(unicodePwd, lmPwdHash->hash);
+			
+			if (lm_hash_ok) {
+				*lm_pwd = lmPwdHash;
+			} else {
+				*lm_pwd = NULL;
+			}
+		}
+	} else {
+		if (nt_pwd) {
+			int num_nt;
+			num_nt = samdb_result_hashes(mem_ctx, msg, "ntPwdHash", &ntPwdHash);
+			if (num_nt == 0) {
+				*nt_pwd = NULL;
+			} else if (num_nt > 1) {
+				return NT_STATUS_INTERNAL_DB_CORRUPTION;
+			} else {
+				*nt_pwd = &ntPwdHash[0];
+			}
+		}
+		if (lm_pwd) {
+			int num_lm;
+			num_lm = samdb_result_hashes(mem_ctx, msg, "lmPwdHash", &lmPwdHash);
+			if (num_lm == 0) {
+				*lm_pwd = NULL;
+			} else if (num_lm > 1) {
+				return NT_STATUS_INTERNAL_DB_CORRUPTION;
+			} else {
+				*lm_pwd = &lmPwdHash[0];
+			}
+		}
+		
+	}
+	return NT_STATUS_OK;
+}
+
+/*
+  pull a samr_LogonHours structutre from a result set. 
+*/
+struct samr_LogonHours samdb_result_logon_hours(TALLOC_CTX *mem_ctx, struct ldb_message *msg, const char *attr)
+{
+	struct samr_LogonHours hours;
+	const int units_per_week = 168;
+	const struct ldb_val *val = ldb_msg_find_ldb_val(msg, attr);
+	ZERO_STRUCT(hours);
+	hours.bitmap = talloc_array_p(mem_ctx, uint8, units_per_week);
+	if (!hours.bitmap) {
+		return hours;
+	}
+	hours.units_per_week = units_per_week;
+	memset(hours.bitmap, 0xFF, units_per_week);
+	if (val) {
+		memcpy(hours.bitmap, val->data, MIN(val->length, units_per_week));
+	}
+	return hours;
+}
+
+/*
+  pull a set of account_flags from a result set. 
+*/
+uint16_t samdb_result_acct_flags(struct ldb_message *msg, const char *attr)
+{
+	uint_t userAccountControl = ldb_msg_find_uint(msg, attr, 0);
+	return samdb_uf2acb(userAccountControl);
+}
+
+/*
+  copy from a template record to a message
+*/
+int samdb_copy_template(void *ctx, TALLOC_CTX *mem_ctx, 
+			struct ldb_message *msg, const char *expression)
+{
+	struct ldb_message **res, *t;
+	int ret, i, j;
+	
+
+	/* pull the template record */
+	ret = samdb_search(ctx, mem_ctx, NULL, &res, NULL, "%s", expression);
+	if (ret != 1) {
+		DEBUG(1,("samdb: ERROR: template '%s' matched %d records\n", 
+			 expression, ret));
+		return -1;
+	}
+	t = res[0];
+
+	for (i=0;i<t->num_elements;i++) {
+		struct ldb_message_element *el = &t->elements[i];
+		/* some elements should not be copied from the template */
+		if (strcasecmp(el->name, "cn") == 0 ||
+		    strcasecmp(el->name, "name") == 0 ||
+		    strcasecmp(el->name, "sAMAccountName") == 0) {
+			continue;
+		}
+		for (j=0;j<el->num_values;j++) {
+			if (strcasecmp(el->name, "objectClass") == 0 &&
+			    (strcasecmp((char *)el->values[j].data, "Template") == 0 ||
+			     strcasecmp((char *)el->values[j].data, "userTemplate") == 0 ||
+			     strcasecmp((char *)el->values[j].data, "groupTemplate") == 0)) {
+				continue;
+			}
+			samdb_msg_add_string(ctx, mem_ctx, msg, el->name, 
+					     (char *)el->values[j].data);
+		}
+	}
+
+	return 0;
+}
+
+
+/*
+  allocate a new id, attempting to do it atomically
+  return 0 on failure, the id on success
+*/
+static NTSTATUS _samdb_allocate_next_id(void *ctx, TALLOC_CTX *mem_ctx, const char *dn, 
+					const char *attr, uint32_t *id)
+{
+	struct ldb_wrap *sam_ctx = ctx;
+	struct ldb_message msg;
+	int ret;
+	const char *str;
+	struct ldb_val vals[2];
+	struct ldb_message_element els[2];
+
+	str = samdb_search_string(ctx, mem_ctx, NULL, attr, "dn=%s", dn);
+	if (!str) {
+		DEBUG(1,("id not found at %s %s\n", dn, attr));
+		return NT_STATUS_OBJECT_NAME_INVALID;
+	}
+
+	*id = strtol(str, NULL, 0);
+	if ((*id)+1 == 0) {
+		/* out of IDs ! */
+		return NT_STATUS_INSUFFICIENT_RESOURCES;
+	}
+
+	/* we do a delete and add as a single operation. That prevents
+	   a race */
+	ZERO_STRUCT(msg);
+	msg.dn = talloc_strdup(mem_ctx, dn);
+	if (!msg.dn) {
+		return NT_STATUS_NO_MEMORY;
+	}
+	msg.num_elements = 2;
+	msg.elements = els;
+
+	els[0].num_values = 1;
+	els[0].values = &vals[0];
+	els[0].flags = LDB_FLAG_MOD_DELETE;
+	els[0].name = talloc_strdup(mem_ctx, attr);
+	if (!els[0].name) {
+		return NT_STATUS_NO_MEMORY;
+	}
+
+	els[1].num_values = 1;
+	els[1].values = &vals[1];
+	els[1].flags = LDB_FLAG_MOD_ADD;
+	els[1].name = els[0].name;
+
+	vals[0].data = talloc_asprintf(mem_ctx, "%u", *id);
+	if (!vals[0].data) {
+		return NT_STATUS_NO_MEMORY;
+	}
+	vals[0].length = strlen(vals[0].data);
+
+	vals[1].data = talloc_asprintf(mem_ctx, "%u", (*id)+1);
+	if (!vals[1].data) {
+		return NT_STATUS_NO_MEMORY;
+	}
+	vals[1].length = strlen(vals[1].data);
+
+	ret = ldb_modify(sam_ctx->ldb, &msg);
+	if (ret != 0) {
+		return NT_STATUS_UNEXPECTED_IO_ERROR;
+	}
+
+	(*id)++;
+
+	return NT_STATUS_OK;
+}
+
+/*
+  allocate a new id, attempting to do it atomically
+  return 0 on failure, the id on success
+*/
+NTSTATUS samdb_allocate_next_id(void *ctx, TALLOC_CTX *mem_ctx, const char *dn, const char *attr,
+				uint32_t *id)
+{
+	int tries = 10;
+	NTSTATUS status;
+
+	/* we need to try multiple times to cope with two account
+	   creations at the same time */
+	while (tries--) {
+		status = _samdb_allocate_next_id(ctx, mem_ctx, dn, attr, id);
+		if (!NT_STATUS_EQUAL(NT_STATUS_UNEXPECTED_IO_ERROR, status)) {
+			break;
+		}
+	}
+
+	if (NT_STATUS_EQUAL(NT_STATUS_UNEXPECTED_IO_ERROR, status)) {
+		DEBUG(1,("Failed to increment id %s at %s\n", attr, dn));
+	}
+
+	return status;
+}
+
+
+/*
+  add a string element to a message
+*/
+int samdb_msg_add_string(void *ctx, TALLOC_CTX *mem_ctx, struct ldb_message *msg,
+			 const char *attr_name, const char *str)
+{
+	struct ldb_wrap *sam_ctx = ctx;
+	char *s = talloc_strdup(mem_ctx, str);
+	char *a = talloc_strdup(mem_ctx, attr_name);
+	if (s == NULL || a == NULL) {
+		return -1;
+	}
+	ldb_set_alloc(sam_ctx->ldb, talloc_realloc_fn, mem_ctx);
+	return ldb_msg_add_string(sam_ctx->ldb, msg, a, s);
+}
+
+/*
+  add a delete element operation to a message
+*/
+int samdb_msg_add_delete(void *ctx, TALLOC_CTX *mem_ctx, struct ldb_message *msg,
+			 const char *attr_name)
+{
+	struct ldb_wrap *sam_ctx = ctx;
+	char *a = talloc_strdup(mem_ctx, attr_name);
+	if (a == NULL) {
+		return -1;
+	}
+	ldb_set_alloc(sam_ctx->ldb, talloc_realloc_fn, mem_ctx);
+	/* we use an empty replace rather than a delete, as it allows for 
+	   samdb_replace() to be used everywhere */
+	return ldb_msg_add_empty(sam_ctx->ldb, msg, a, LDB_FLAG_MOD_REPLACE);
+}
+
+/*
+  add a uint_t element to a message
+*/
+int samdb_msg_add_uint(void *ctx, TALLOC_CTX *mem_ctx, struct ldb_message *msg,
+		       const char *attr_name, uint_t v)
+{
+	const char *s = talloc_asprintf(mem_ctx, "%u", v);
+	return samdb_msg_add_string(ctx, mem_ctx, msg, attr_name, s);
+}
+
+/*
+  add a (signed) int64_t element to a message
+*/
+int samdb_msg_add_int64(void *ctx, TALLOC_CTX *mem_ctx, struct ldb_message *msg,
+			const char *attr_name, int64_t v)
+{
+	const char *s = talloc_asprintf(mem_ctx, "%lld", v);
+	return samdb_msg_add_string(ctx, mem_ctx, msg, attr_name, s);
+}
+
+/*
+  add a uint64_t element to a message
+*/
+int samdb_msg_add_uint64(void *ctx, TALLOC_CTX *mem_ctx, struct ldb_message *msg,
+			const char *attr_name, uint64_t v)
+{
+	const char *s = talloc_asprintf(mem_ctx, "%llu", v);
+	return samdb_msg_add_string(ctx, mem_ctx, msg, attr_name, s);
+}
+
+/*
+  add a samr_Password element to a message
+*/
+int samdb_msg_add_hash(void *ctx, TALLOC_CTX *mem_ctx, struct ldb_message *msg,
+		       const char *attr_name, struct samr_Password hash)
+{
+	struct ldb_wrap *sam_ctx = ctx;
+	struct ldb_val val;
+	val.data = talloc(mem_ctx, 16);
+	val.length = 16;
+	if (!val.data) {
+		return -1;
+	}
+	memcpy(val.data, hash.hash, 16);
+	ldb_set_alloc(sam_ctx->ldb, talloc_realloc_fn, mem_ctx);
+	return ldb_msg_add_value(sam_ctx->ldb, msg, attr_name, &val);
+}
+
+/*
+  add a samr_Password array to a message
+*/
+int samdb_msg_add_hashes(void *ctx, TALLOC_CTX *mem_ctx, struct ldb_message *msg,
+			 const char *attr_name, struct samr_Password *hashes, uint_t count)
+{
+	struct ldb_wrap *sam_ctx = ctx;
+	struct ldb_val val;
+	int i;
+	val.data = talloc(mem_ctx, count*16);
+	val.length = count*16;
+	if (!val.data) {
+		return -1;
+	}
+	for (i=0;i<count;i++) {
+		memcpy(i*16 + (char *)val.data, hashes[i].hash, 16);
+	}
+	ldb_set_alloc(sam_ctx->ldb, talloc_realloc_fn, mem_ctx);
+	return ldb_msg_add_value(sam_ctx->ldb, msg, attr_name, &val);
+}
+
+/*
+  add a acct_flags element to a message
+*/
+int samdb_msg_add_acct_flags(void *ctx, TALLOC_CTX *mem_ctx, struct ldb_message *msg,
+			     const char *attr_name, uint32_t v)
+{
+	return samdb_msg_add_uint(ctx, mem_ctx, msg, attr_name, samdb_acb2uf(v));
+}
+
+/*
+  add a logon_hours element to a message
+*/
+int samdb_msg_add_logon_hours(void *ctx, TALLOC_CTX *mem_ctx, struct ldb_message *msg,
+			      const char *attr_name, struct samr_LogonHours *hours)
+{
+	struct ldb_wrap *sam_ctx = ctx;
+	struct ldb_val val;
+	val.length = hours->units_per_week / 8;
+	val.data = hours->bitmap;
+	ldb_set_alloc(sam_ctx->ldb, talloc_realloc_fn, mem_ctx);
+	return ldb_msg_add_value(sam_ctx->ldb, msg, attr_name, &val);
+}
+
+/*
+  set a string element in a message
+*/
+int samdb_msg_set_string(void *ctx, TALLOC_CTX *mem_ctx, struct ldb_message *msg,
+			 const char *attr_name, const char *str)
+{
+	struct ldb_wrap *sam_ctx = ctx;
+	struct ldb_message_element *el;
+
+	ldb_set_alloc(sam_ctx->ldb, talloc_realloc_fn, mem_ctx);
+
+	el = ldb_msg_find_element(msg, attr_name);
+	if (el) {
+		el->num_values = 0;
+	}
+	return samdb_msg_add_string(ctx, mem_ctx, msg, attr_name, str);
+}
+
+/*
+  set a ldaptime element in a message
+*/
+int samdb_msg_set_ldaptime(void *ctx, TALLOC_CTX *mem_ctx, struct ldb_message *msg,
+			   const char *attr_name, time_t t)
+{
+	char *str = ldap_timestring(mem_ctx, t);
+	if (!str) {
+		return -1;
+	}
+	return samdb_msg_set_string(ctx, mem_ctx, msg, attr_name, str);
+}
+
+/*
+  add a record
+*/
+int samdb_add(void *ctx, TALLOC_CTX *mem_ctx, struct ldb_message *msg)
+{
+	struct ldb_wrap *sam_ctx = ctx;
+
+	ldb_set_alloc(sam_ctx->ldb, talloc_realloc_fn, mem_ctx);
+	return ldb_add(sam_ctx->ldb, msg);
+}
+
+/*
+  delete a record
+*/
+int samdb_delete(void *ctx, TALLOC_CTX *mem_ctx, const char *dn)
+{
+	struct ldb_wrap *sam_ctx = ctx;
+
+	ldb_set_alloc(sam_ctx->ldb, talloc_realloc_fn, mem_ctx);
+	return ldb_delete(sam_ctx->ldb, dn);
+}
+
+/*
+  modify a record
+*/
+int samdb_modify(void *ctx, TALLOC_CTX *mem_ctx, struct ldb_message *msg)
+{
+	struct ldb_wrap *sam_ctx = ctx;
+
+	ldb_set_alloc(sam_ctx->ldb, talloc_realloc_fn, mem_ctx);
+	return ldb_modify(sam_ctx->ldb, msg);
+}
+
+/*
+  replace elements in a record
+*/
+int samdb_replace(void *ctx, TALLOC_CTX *mem_ctx, struct ldb_message *msg)
+{
+	int i;
+
+	/* mark all the message elements as LDB_FLAG_MOD_REPLACE */
+	for (i=0;i<msg->num_elements;i++) {
+		msg->elements[i].flags = LDB_FLAG_MOD_REPLACE;
+	}
+
+	/* modify the samdb record */
+	return samdb_modify(ctx, mem_ctx, msg);
+}
+
+/*
+  return a default security descriptor
+*/
+struct security_descriptor *samdb_default_security_descriptor(TALLOC_CTX *mem_ctx)
+{
+	struct security_descriptor *sd;
+
+	sd = security_descriptor_initialise(mem_ctx);
+
+	return sd;
+}