libcli/security: move secdesc.c to the top level libcli/security

This code does not rely on lp_ or other source3 only functions, so can
be part of the common library.

Andrew Bartlett

4 files changed, 823 insertions, 1 deletions

diff --git a/libcli/security/secdesc.c b/libcli/security/secdesc.c
new file mode 100644
index 0000000000..5d75f073f4
--- /dev/null
+++ b/libcli/security/secdesc.c
@@ -0,0 +1,719 @@
+/*
+ *  Unix SMB/Netbios implementation.
+ *  SEC_DESC handling functions
+ *  Copyright (C) Andrew Tridgell              1992-1998,
+ *  Copyright (C) Jeremy R. Allison            1995-2003.
+ *  Copyright (C) Luke Kenneth Casson Leighton 1996-1998,
+ *  Copyright (C) Paul Ashton                  1997-1998.
+ *
+ *  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 3 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, see <http://www.gnu.org/licenses/>.
+ */
+
+#include "includes.h"
+#include "librpc/gen_ndr/ndr_security.h"
+#include "libcli/security/security.h"
+
+#define ALL_SECURITY_INFORMATION (SECINFO_OWNER|SECINFO_GROUP|\
+					SECINFO_DACL|SECINFO_SACL|\
+					SECINFO_UNPROTECTED_SACL|\
+					SECINFO_UNPROTECTED_DACL|\
+					SECINFO_PROTECTED_SACL|\
+					SECINFO_PROTECTED_DACL)
+
+/* Map generic permissions to file object specific permissions */
+
+const struct generic_mapping file_generic_mapping = {
+	FILE_GENERIC_READ,
+	FILE_GENERIC_WRITE,
+	FILE_GENERIC_EXECUTE,
+	FILE_GENERIC_ALL
+};
+
+/*******************************************************************
+ Given a security_descriptor return the sec_info.
+********************************************************************/
+
+uint32_t get_sec_info(const struct security_descriptor *sd)
+{
+	uint32_t sec_info = ALL_SECURITY_INFORMATION;
+
+	SMB_ASSERT(sd);
+
+	if (sd->owner_sid == NULL) {
+		sec_info &= ~SECINFO_OWNER;
+	}
+	if (sd->group_sid == NULL) {
+		sec_info &= ~SECINFO_GROUP;
+	}
+	if (sd->sacl == NULL) {
+		sec_info &= ~SECINFO_SACL;
+	}
+	if (sd->dacl == NULL) {
+		sec_info &= ~SECINFO_DACL;
+	}
+
+	return sec_info;
+}
+
+
+/*******************************************************************
+ Merge part of security descriptor old_sec in to the empty sections of
+ security descriptor new_sec.
+********************************************************************/
+
+struct sec_desc_buf *sec_desc_merge_buf(TALLOC_CTX *ctx, struct sec_desc_buf *new_sdb, struct sec_desc_buf *old_sdb)
+{
+	struct dom_sid *owner_sid, *group_sid;
+	struct sec_desc_buf *return_sdb;
+	struct security_acl *dacl, *sacl;
+	struct security_descriptor *psd = NULL;
+	uint16_t secdesc_type;
+	size_t secdesc_size;
+
+	/* Copy over owner and group sids.  There seems to be no flag for
+	   this so just check the pointer values. */
+
+	owner_sid = new_sdb->sd->owner_sid ? new_sdb->sd->owner_sid :
+		old_sdb->sd->owner_sid;
+
+	group_sid = new_sdb->sd->group_sid ? new_sdb->sd->group_sid :
+		old_sdb->sd->group_sid;
+
+	secdesc_type = new_sdb->sd->type;
+
+	/* Ignore changes to the system ACL.  This has the effect of making
+	   changes through the security tab audit button not sticking.
+	   Perhaps in future Samba could implement these settings somehow. */
+
+	sacl = NULL;
+	secdesc_type &= ~SEC_DESC_SACL_PRESENT;
+
+	/* Copy across discretionary ACL */
+
+	if (secdesc_type & SEC_DESC_DACL_PRESENT) {
+		dacl = new_sdb->sd->dacl;
+	} else {
+		dacl = old_sdb->sd->dacl;
+	}
+
+	/* Create new security descriptor from bits */
+
+	psd = make_sec_desc(ctx, new_sdb->sd->revision, secdesc_type,
+			    owner_sid, group_sid, sacl, dacl, &secdesc_size);
+
+	return_sdb = make_sec_desc_buf(ctx, secdesc_size, psd);
+
+	return(return_sdb);
+}
+
+struct security_descriptor *sec_desc_merge(TALLOC_CTX *ctx, struct security_descriptor *new_sdb, struct security_descriptor *old_sdb)
+{
+	struct dom_sid *owner_sid, *group_sid;
+	struct security_acl *dacl, *sacl;
+	struct security_descriptor *psd = NULL;
+	uint16_t secdesc_type;
+	size_t secdesc_size;
+
+	/* Copy over owner and group sids.  There seems to be no flag for
+	   this so just check the pointer values. */
+
+	owner_sid = new_sdb->owner_sid ? new_sdb->owner_sid :
+		old_sdb->owner_sid;
+
+	group_sid = new_sdb->group_sid ? new_sdb->group_sid :
+		old_sdb->group_sid;
+
+	secdesc_type = new_sdb->type;
+
+	/* Ignore changes to the system ACL.  This has the effect of making
+	   changes through the security tab audit button not sticking.
+	   Perhaps in future Samba could implement these settings somehow. */
+
+	sacl = NULL;
+	secdesc_type &= ~SEC_DESC_SACL_PRESENT;
+
+	/* Copy across discretionary ACL */
+
+	if (secdesc_type & SEC_DESC_DACL_PRESENT) {
+		dacl = new_sdb->dacl;
+	} else {
+		dacl = old_sdb->dacl;
+	}
+
+	/* Create new security descriptor from bits */
+	psd = make_sec_desc(ctx, new_sdb->revision, secdesc_type,
+			    owner_sid, group_sid, sacl, dacl, &secdesc_size);
+
+	return psd;
+}
+
+/*******************************************************************
+ Creates a struct security_descriptor structure
+********************************************************************/
+
+#define  SEC_DESC_HEADER_SIZE (2 * sizeof(uint16_t) + 4 * sizeof(uint32_t))
+
+struct security_descriptor *make_sec_desc(TALLOC_CTX *ctx,
+			enum security_descriptor_revision revision,
+			uint16_t type,
+			const struct dom_sid *owner_sid, const struct dom_sid *grp_sid,
+			struct security_acl *sacl, struct security_acl *dacl, size_t *sd_size)
+{
+	struct security_descriptor *dst;
+	uint32_t offset     = 0;
+
+	*sd_size = 0;
+
+	if(( dst = talloc_zero(ctx, struct security_descriptor)) == NULL)
+		return NULL;
+
+	dst->revision = revision;
+	dst->type = type;
+
+	if (sacl)
+		dst->type |= SEC_DESC_SACL_PRESENT;
+	if (dacl)
+		dst->type |= SEC_DESC_DACL_PRESENT;
+
+	dst->owner_sid = NULL;
+	dst->group_sid   = NULL;
+	dst->sacl      = NULL;
+	dst->dacl      = NULL;
+
+	if(owner_sid && ((dst->owner_sid = dom_sid_dup(dst,owner_sid)) == NULL))
+		goto error_exit;
+
+	if(grp_sid && ((dst->group_sid = dom_sid_dup(dst,grp_sid)) == NULL))
+		goto error_exit;
+
+	if(sacl && ((dst->sacl = dup_sec_acl(dst, sacl)) == NULL))
+		goto error_exit;
+
+	if(dacl && ((dst->dacl = dup_sec_acl(dst, dacl)) == NULL))
+		goto error_exit;
+
+	offset = SEC_DESC_HEADER_SIZE;
+
+	/*
+	 * Work out the linearization sizes.
+	 */
+
+	if (dst->sacl != NULL) {
+		offset += dst->sacl->size;
+	}
+	if (dst->dacl != NULL) {
+		offset += dst->dacl->size;
+	}
+
+	if (dst->owner_sid != NULL) {
+		offset += ndr_size_dom_sid(dst->owner_sid, 0);
+	}
+
+	if (dst->group_sid != NULL) {
+		offset += ndr_size_dom_sid(dst->group_sid, 0);
+	}
+
+	*sd_size = (size_t)offset;
+	return dst;
+
+error_exit:
+
+	*sd_size = 0;
+	return NULL;
+}
+
+/*******************************************************************
+ Duplicate a struct security_descriptor structure.
+********************************************************************/
+
+struct security_descriptor *dup_sec_desc(TALLOC_CTX *ctx, const struct security_descriptor *src)
+{
+	size_t dummy;
+
+	if(src == NULL)
+		return NULL;
+
+	return make_sec_desc( ctx, src->revision, src->type,
+				src->owner_sid, src->group_sid, src->sacl,
+				src->dacl, &dummy);
+}
+
+/*******************************************************************
+ Convert a secdesc into a byte stream
+********************************************************************/
+NTSTATUS marshall_sec_desc(TALLOC_CTX *mem_ctx,
+			   struct security_descriptor *secdesc,
+			   uint8_t **data, size_t *len)
+{
+	DATA_BLOB blob;
+	enum ndr_err_code ndr_err;
+
+	ndr_err = ndr_push_struct_blob(
+		&blob, mem_ctx, secdesc,
+		(ndr_push_flags_fn_t)ndr_push_security_descriptor);
+
+	if (!NDR_ERR_CODE_IS_SUCCESS(ndr_err)) {
+		DEBUG(0, ("ndr_push_security_descriptor failed: %s\n",
+			  ndr_errstr(ndr_err)));
+		return ndr_map_error2ntstatus(ndr_err);
+	}
+
+	*data = blob.data;
+	*len = blob.length;
+	return NT_STATUS_OK;
+}
+
+/*******************************************************************
+ Convert a secdesc_buf into a byte stream
+********************************************************************/
+
+NTSTATUS marshall_sec_desc_buf(TALLOC_CTX *mem_ctx,
+			       struct sec_desc_buf *secdesc_buf,
+			       uint8_t **data, size_t *len)
+{
+	DATA_BLOB blob;
+	enum ndr_err_code ndr_err;
+
+	ndr_err = ndr_push_struct_blob(
+		&blob, mem_ctx, secdesc_buf,
+		(ndr_push_flags_fn_t)ndr_push_sec_desc_buf);
+
+	if (!NDR_ERR_CODE_IS_SUCCESS(ndr_err)) {
+		DEBUG(0, ("ndr_push_sec_desc_buf failed: %s\n",
+			  ndr_errstr(ndr_err)));
+		return ndr_map_error2ntstatus(ndr_err);
+	}
+
+	*data = blob.data;
+	*len = blob.length;
+	return NT_STATUS_OK;
+}
+
+/*******************************************************************
+ Parse a byte stream into a secdesc
+********************************************************************/
+NTSTATUS unmarshall_sec_desc(TALLOC_CTX *mem_ctx, uint8_t *data, size_t len,
+			     struct security_descriptor **psecdesc)
+{
+	DATA_BLOB blob;
+	enum ndr_err_code ndr_err;
+	struct security_descriptor *result;
+
+	if ((data == NULL) || (len == 0)) {
+		return NT_STATUS_INVALID_PARAMETER;
+	}
+
+	result = talloc_zero(mem_ctx, struct security_descriptor);
+	if (result == NULL) {
+		return NT_STATUS_NO_MEMORY;
+	}
+
+	blob = data_blob_const(data, len);
+
+	ndr_err = ndr_pull_struct_blob(&blob, result, result,
+		(ndr_pull_flags_fn_t)ndr_pull_security_descriptor);
+
+	if (!NDR_ERR_CODE_IS_SUCCESS(ndr_err)) {
+		DEBUG(0, ("ndr_pull_security_descriptor failed: %s\n",
+			  ndr_errstr(ndr_err)));
+		TALLOC_FREE(result);
+		return ndr_map_error2ntstatus(ndr_err);
+	}
+
+	*psecdesc = result;
+	return NT_STATUS_OK;
+}
+
+/*******************************************************************
+ Parse a byte stream into a sec_desc_buf
+********************************************************************/
+
+NTSTATUS unmarshall_sec_desc_buf(TALLOC_CTX *mem_ctx, uint8_t *data, size_t len,
+				 struct sec_desc_buf **psecdesc_buf)
+{
+	DATA_BLOB blob;
+	enum ndr_err_code ndr_err;
+	struct sec_desc_buf *result;
+
+	if ((data == NULL) || (len == 0)) {
+		return NT_STATUS_INVALID_PARAMETER;
+	}
+
+	result = talloc_zero(mem_ctx, struct sec_desc_buf);
+	if (result == NULL) {
+		return NT_STATUS_NO_MEMORY;
+	}
+
+	blob = data_blob_const(data, len);
+
+	ndr_err = ndr_pull_struct_blob(&blob, result, result,
+		(ndr_pull_flags_fn_t)ndr_pull_sec_desc_buf);
+
+	if (!NDR_ERR_CODE_IS_SUCCESS(ndr_err)) {
+		DEBUG(0, ("ndr_pull_sec_desc_buf failed: %s\n",
+			  ndr_errstr(ndr_err)));
+		TALLOC_FREE(result);
+		return ndr_map_error2ntstatus(ndr_err);
+	}
+
+	*psecdesc_buf = result;
+	return NT_STATUS_OK;
+}
+
+/*******************************************************************
+ Creates a struct security_descriptor structure with typical defaults.
+********************************************************************/
+
+struct security_descriptor *make_standard_sec_desc(TALLOC_CTX *ctx, const struct dom_sid *owner_sid, const struct dom_sid *grp_sid,
+				 struct security_acl *dacl, size_t *sd_size)
+{
+	return make_sec_desc(ctx, SECURITY_DESCRIPTOR_REVISION_1,
+			     SEC_DESC_SELF_RELATIVE, owner_sid, grp_sid, NULL,
+			     dacl, sd_size);
+}
+
+/*******************************************************************
+ Creates a struct sec_desc_buf structure.
+********************************************************************/
+
+struct sec_desc_buf *make_sec_desc_buf(TALLOC_CTX *ctx, size_t len, struct security_descriptor *sec_desc)
+{
+	struct sec_desc_buf *dst;
+
+	if((dst = talloc_zero(ctx, struct sec_desc_buf)) == NULL)
+		return NULL;
+
+	/* max buffer size (allocated size) */
+	dst->sd_size = (uint32_t)len;
+
+	if(sec_desc && ((dst->sd = dup_sec_desc(ctx, sec_desc)) == NULL)) {
+		return NULL;
+	}
+
+	return dst;
+}
+
+/*******************************************************************
+ Duplicates a struct sec_desc_buf structure.
+********************************************************************/
+
+struct sec_desc_buf *dup_sec_desc_buf(TALLOC_CTX *ctx, struct sec_desc_buf *src)
+{
+	if(src == NULL)
+		return NULL;
+
+	return make_sec_desc_buf( ctx, src->sd_size, src->sd);
+}
+
+/*******************************************************************
+ Add a new SID with its permissions to struct security_descriptor.
+********************************************************************/
+
+NTSTATUS sec_desc_add_sid(TALLOC_CTX *ctx, struct security_descriptor **psd, const struct dom_sid *sid, uint32_t mask, size_t *sd_size)
+{
+	struct security_descriptor *sd   = 0;
+	struct security_acl  *dacl = 0;
+	struct security_ace  *ace  = 0;
+	NTSTATUS  status;
+
+	if (!ctx || !psd || !sid || !sd_size)
+		return NT_STATUS_INVALID_PARAMETER;
+
+	*sd_size = 0;
+
+	status = sec_ace_add_sid(ctx, &ace, psd[0]->dacl->aces, &psd[0]->dacl->num_aces, sid, mask);
+
+	if (!NT_STATUS_IS_OK(status))
+		return status;
+
+	if (!(dacl = make_sec_acl(ctx, psd[0]->dacl->revision, psd[0]->dacl->num_aces, ace)))
+		return NT_STATUS_UNSUCCESSFUL;
+
+	if (!(sd = make_sec_desc(ctx, psd[0]->revision, psd[0]->type, psd[0]->owner_sid,
+		psd[0]->group_sid, psd[0]->sacl, dacl, sd_size)))
+		return NT_STATUS_UNSUCCESSFUL;
+
+	*psd = sd;
+	 sd  = 0;
+	return NT_STATUS_OK;
+}
+
+/*******************************************************************
+ Modify a SID's permissions in a struct security_descriptor.
+********************************************************************/
+
+NTSTATUS sec_desc_mod_sid(struct security_descriptor *sd, struct dom_sid *sid, uint32_t mask)
+{
+	NTSTATUS status;
+
+	if (!sd || !sid)
+		return NT_STATUS_INVALID_PARAMETER;
+
+	status = sec_ace_mod_sid(sd->dacl->aces, sd->dacl->num_aces, sid, mask);
+
+	if (!NT_STATUS_IS_OK(status))
+		return status;
+
+	return NT_STATUS_OK;
+}
+
+/*******************************************************************
+ Delete a SID from a struct security_descriptor.
+********************************************************************/
+
+NTSTATUS sec_desc_del_sid(TALLOC_CTX *ctx, struct security_descriptor **psd, struct dom_sid *sid, size_t *sd_size)
+{
+	struct security_descriptor *sd   = 0;
+	struct security_acl  *dacl = 0;
+	struct security_ace  *ace  = 0;
+	NTSTATUS  status;
+
+	if (!ctx || !psd[0] || !sid || !sd_size)
+		return NT_STATUS_INVALID_PARAMETER;
+
+	*sd_size = 0;
+
+	status = sec_ace_del_sid(ctx, &ace, psd[0]->dacl->aces, &psd[0]->dacl->num_aces, sid);
+
+	if (!NT_STATUS_IS_OK(status))
+		return status;
+
+	if (!(dacl = make_sec_acl(ctx, psd[0]->dacl->revision, psd[0]->dacl->num_aces, ace)))
+		return NT_STATUS_UNSUCCESSFUL;
+
+	if (!(sd = make_sec_desc(ctx, psd[0]->revision, psd[0]->type, psd[0]->owner_sid,
+		psd[0]->group_sid, psd[0]->sacl, dacl, sd_size)))
+		return NT_STATUS_UNSUCCESSFUL;
+
+	*psd = sd;
+	 sd  = 0;
+	return NT_STATUS_OK;
+}
+
+/*
+ * Determine if an struct security_ace is inheritable
+ */
+
+static bool is_inheritable_ace(const struct security_ace *ace,
+				bool container)
+{
+	if (!container) {
+		return ((ace->flags & SEC_ACE_FLAG_OBJECT_INHERIT) != 0);
+	}
+
+	if (ace->flags & SEC_ACE_FLAG_CONTAINER_INHERIT) {
+		return true;
+	}
+
+	if ((ace->flags & SEC_ACE_FLAG_OBJECT_INHERIT) &&
+			!(ace->flags & SEC_ACE_FLAG_NO_PROPAGATE_INHERIT)) {
+		return true;
+	}
+
+	return false;
+}
+
+/*
+ * Does a security descriptor have any inheritable components for
+ * the newly created type ?
+ */
+
+bool sd_has_inheritable_components(const struct security_descriptor *parent_ctr, bool container)
+{
+	unsigned int i;
+	const struct security_acl *the_acl = parent_ctr->dacl;
+
+	for (i = 0; i < the_acl->num_aces; i++) {
+		const struct security_ace *ace = &the_acl->aces[i];
+
+		if (is_inheritable_ace(ace, container)) {
+			return true;
+		}
+	}
+	return false;
+}
+
+/* Create a child security descriptor using another security descriptor as
+   the parent container.  This child object can either be a container or
+   non-container object. */
+
+NTSTATUS se_create_child_secdesc(TALLOC_CTX *ctx,
+					struct security_descriptor **ppsd,
+					size_t *psize,
+					const struct security_descriptor *parent_ctr,
+					const struct dom_sid *owner_sid,
+					const struct dom_sid *group_sid,
+					bool container)
+{
+	struct security_acl *new_dacl = NULL, *the_acl = NULL;
+	struct security_ace *new_ace_list = NULL;
+	unsigned int new_ace_list_ndx = 0, i;
+
+	TALLOC_CTX *frame;
+
+	*ppsd = NULL;
+	*psize = 0;
+
+	/* Currently we only process the dacl when creating the child.  The
+	   sacl should also be processed but this is left out as sacls are
+	   not implemented in Samba at the moment.*/
+
+	the_acl = parent_ctr->dacl;
+
+	if (the_acl->num_aces) {
+		if (2*the_acl->num_aces < the_acl->num_aces) {
+			return NT_STATUS_NO_MEMORY;
+		}
+
+		if (!(new_ace_list = talloc_array(ctx, struct security_ace,
+						  2*the_acl->num_aces))) {
+			return NT_STATUS_NO_MEMORY;
+		}
+	} else {
+		new_ace_list = NULL;
+	}
+
+	frame = talloc_stackframe();
+
+	for (i = 0; i < the_acl->num_aces; i++) {
+		const struct security_ace *ace = &the_acl->aces[i];
+		struct security_ace *new_ace = &new_ace_list[new_ace_list_ndx];
+		const struct dom_sid *ptrustee = &ace->trustee;
+		const struct dom_sid *creator = NULL;
+		uint8_t new_flags = ace->flags;
+
+		if (!is_inheritable_ace(ace, container)) {
+			continue;
+		}
+
+		/* see the RAW-ACLS inheritance test for details on these rules */
+		if (!container) {
+			new_flags = 0;
+		} else {
+			new_flags &= ~SEC_ACE_FLAG_INHERIT_ONLY;
+
+			if (!(new_flags & SEC_ACE_FLAG_CONTAINER_INHERIT)) {
+				new_flags |= SEC_ACE_FLAG_INHERIT_ONLY;
+			}
+			if (new_flags & SEC_ACE_FLAG_NO_PROPAGATE_INHERIT) {
+				new_flags = 0;
+			}
+		}
+
+		/* The CREATOR sids are special when inherited */
+		if (dom_sid_equal(ptrustee, &global_sid_Creator_Owner)) {
+			creator = &global_sid_Creator_Owner;
+			ptrustee = owner_sid;
+		} else if (dom_sid_equal(ptrustee, &global_sid_Creator_Group)) {
+			creator = &global_sid_Creator_Group;
+			ptrustee = group_sid;
+		}
+
+		if (creator && container &&
+				(new_flags & SEC_ACE_FLAG_CONTAINER_INHERIT)) {
+
+			/* First add the regular ACE entry. */
+			init_sec_ace(new_ace, ptrustee, ace->type,
+				ace->access_mask, 0);
+
+			DEBUG(5,("se_create_child_secdesc(): %s:%d/0x%02x/0x%08x"
+				 " inherited as %s:%d/0x%02x/0x%08x\n",
+				 dom_sid_string(frame, &ace->trustee),
+				 ace->type, ace->flags, ace->access_mask,
+				 dom_sid_string(frame, &new_ace->trustee),
+				 new_ace->type, new_ace->flags,
+				 new_ace->access_mask));
+
+			new_ace_list_ndx++;
+
+			/* Now add the extra creator ACE. */
+			new_ace = &new_ace_list[new_ace_list_ndx];
+
+			ptrustee = creator;
+			new_flags |= SEC_ACE_FLAG_INHERIT_ONLY;
+
+		} else if (container &&
+				!(ace->flags & SEC_ACE_FLAG_NO_PROPAGATE_INHERIT)) {
+			ptrustee = &ace->trustee;
+		}
+
+		init_sec_ace(new_ace, ptrustee, ace->type,
+			     ace->access_mask, new_flags);
+
+		DEBUG(5, ("se_create_child_secdesc(): %s:%d/0x%02x/0x%08x "
+			  " inherited as %s:%d/0x%02x/0x%08x\n",
+			  dom_sid_string(frame, &ace->trustee),
+			  ace->type, ace->flags, ace->access_mask,
+			  dom_sid_string(frame, &ace->trustee),
+			  new_ace->type, new_ace->flags,
+			  new_ace->access_mask));
+
+		new_ace_list_ndx++;
+	}
+
+	talloc_free(frame);
+
+	/* Create child security descriptor to return */
+	if (new_ace_list_ndx) {
+		new_dacl = make_sec_acl(ctx,
+				NT4_ACL_REVISION,
+				new_ace_list_ndx,
+				new_ace_list);
+
+		if (!new_dacl) {
+			return NT_STATUS_NO_MEMORY;
+		}
+	}
+
+	*ppsd = make_sec_desc(ctx,
+			SECURITY_DESCRIPTOR_REVISION_1,
+			SEC_DESC_SELF_RELATIVE|SEC_DESC_DACL_PRESENT,
+			owner_sid,
+			group_sid,
+			NULL,
+			new_dacl,
+			psize);
+	if (!*ppsd) {
+		return NT_STATUS_NO_MEMORY;
+	}
+	return NT_STATUS_OK;
+}
+
+NTSTATUS se_create_child_secdesc_buf(TALLOC_CTX *ctx,
+					struct sec_desc_buf **ppsdb,
+					const struct security_descriptor *parent_ctr,
+					bool container)
+{
+	NTSTATUS status;
+	size_t size = 0;
+	struct security_descriptor *sd = NULL;
+
+	*ppsdb = NULL;
+	status = se_create_child_secdesc(ctx,
+					&sd,
+					&size,
+					parent_ctr,
+					parent_ctr->owner_sid,
+					parent_ctr->group_sid,
+					container);
+	if (!NT_STATUS_IS_OK(status)) {
+		return status;
+	}
+
+	*ppsdb = make_sec_desc_buf(ctx, size, sd);
+	if (!*ppsdb) {
+		return NT_STATUS_NO_MEMORY;
+	}
+	return NT_STATUS_OK;
+}
diff --git a/libcli/security/secdesc.h b/libcli/security/secdesc.h
new file mode 100644
index 0000000000..eae8100fc6
--- /dev/null
+++ b/libcli/security/secdesc.h
@@ -0,0 +1,102 @@
+#ifndef _SECDESC_H_
+#define _SECDESC_H_
+
+/* The following definitions come from libcli/security/secdesc.c  */
+#include "librpc/gen_ndr/security.h"
+
+/*******************************************************************
+ Given a security_descriptor return the sec_info.
+********************************************************************/
+uint32_t get_sec_info(const struct security_descriptor *sd);
+
+/*******************************************************************
+ Merge part of security descriptor old_sec in to the empty sections of
+ security descriptor new_sec.
+********************************************************************/
+struct sec_desc_buf *sec_desc_merge_buf(TALLOC_CTX *ctx, struct sec_desc_buf *new_sdb, struct sec_desc_buf *old_sdb);
+struct security_descriptor *sec_desc_merge(TALLOC_CTX *ctx, struct security_descriptor *new_sdb, struct security_descriptor *old_sdb);
+
+/*******************************************************************
+ Creates a struct security_descriptor structure
+********************************************************************/
+struct security_descriptor *make_sec_desc(TALLOC_CTX *ctx,
+			enum security_descriptor_revision revision,
+			uint16_t type,
+			const struct dom_sid *owner_sid, const struct dom_sid *grp_sid,
+			struct security_acl *sacl, struct security_acl *dacl, size_t *sd_size);
+
+/*******************************************************************
+ Duplicate a struct security_descriptor structure.
+********************************************************************/
+struct security_descriptor *dup_sec_desc(TALLOC_CTX *ctx, const struct security_descriptor *src);
+
+/*******************************************************************
+ Convert a secdesc into a byte stream
+********************************************************************/
+NTSTATUS marshall_sec_desc(TALLOC_CTX *mem_ctx,
+			   struct security_descriptor *secdesc,
+			   uint8_t **data, size_t *len);
+
+/*******************************************************************
+ Convert a secdesc_buf into a byte stream
+********************************************************************/
+NTSTATUS marshall_sec_desc_buf(TALLOC_CTX *mem_ctx,
+			       struct sec_desc_buf *secdesc_buf,
+			       uint8_t **data, size_t *len);
+
+/*******************************************************************
+ Parse a byte stream into a secdesc
+********************************************************************/
+NTSTATUS unmarshall_sec_desc(TALLOC_CTX *mem_ctx, uint8_t *data, size_t len,
+			     struct security_descriptor **psecdesc);
+
+/*******************************************************************
+ Parse a byte stream into a sec_desc_buf
+********************************************************************/
+NTSTATUS unmarshall_sec_desc_buf(TALLOC_CTX *mem_ctx, uint8_t *data, size_t len,
+				 struct sec_desc_buf **psecdesc_buf);
+
+/*******************************************************************
+ Creates a struct security_descriptor structure with typical defaults.
+********************************************************************/
+struct security_descriptor *make_standard_sec_desc(TALLOC_CTX *ctx, const struct dom_sid *owner_sid, const struct dom_sid *grp_sid,
+				 struct security_acl *dacl, size_t *sd_size);
+
+/*******************************************************************
+ Creates a struct sec_desc_buf structure.
+********************************************************************/
+struct sec_desc_buf *make_sec_desc_buf(TALLOC_CTX *ctx, size_t len, struct security_descriptor *sec_desc);
+
+/*******************************************************************
+ Duplicates a struct sec_desc_buf structure.
+********************************************************************/
+struct sec_desc_buf *dup_sec_desc_buf(TALLOC_CTX *ctx, struct sec_desc_buf *src);
+
+/*******************************************************************
+ Add a new SID with its permissions to struct security_descriptor.
+********************************************************************/
+NTSTATUS sec_desc_add_sid(TALLOC_CTX *ctx, struct security_descriptor **psd, const struct dom_sid *sid, uint32_t mask, size_t *sd_size);
+
+/*******************************************************************
+ Modify a SID's permissions in a struct security_descriptor.
+********************************************************************/
+NTSTATUS sec_desc_mod_sid(struct security_descriptor *sd, struct dom_sid *sid, uint32_t mask);
+
+/*******************************************************************
+ Delete a SID from a struct security_descriptor.
+********************************************************************/
+NTSTATUS sec_desc_del_sid(TALLOC_CTX *ctx, struct security_descriptor **psd, struct dom_sid *sid, size_t *sd_size);
+bool sd_has_inheritable_components(const struct security_descriptor *parent_ctr, bool container);
+NTSTATUS se_create_child_secdesc(TALLOC_CTX *ctx,
+					struct security_descriptor **ppsd,
+					size_t *psize,
+					const struct security_descriptor *parent_ctr,
+					const struct dom_sid *owner_sid,
+					const struct dom_sid *group_sid,
+					bool container);
+NTSTATUS se_create_child_secdesc_buf(TALLOC_CTX *ctx,
+					struct sec_desc_buf **ppsdb,
+					const struct security_descriptor *parent_ctr,
+					bool container);
+
+#endif /* _SECDESC_H_ */
diff --git a/libcli/security/security.h b/libcli/security/security.h
index 1a9f4fa386..659d34157b 100644
--- a/libcli/security/security.h
+++ b/libcli/security/security.h
@@ -100,6 +100,7 @@ struct object_tree {
 #include "libcli/security/dom_sid.h"
 #include "libcli/security/secace.h"
 #include "libcli/security/secacl.h"
+#include "libcli/security/secdesc.h"
 #include "libcli/security/security_descriptor.h"
 #include "libcli/security/security_token.h"
 #include "libcli/security/sddl.h"
diff --git a/libcli/security/wscript_build b/libcli/security/wscript_build
index 3f2e06a908..940ee700f2 100644
--- a/libcli/security/wscript_build
+++ b/libcli/security/wscript_build
@@ -2,7 +2,7 @@
 
 
 bld.SAMBA_LIBRARY('security',
-                  source='dom_sid.c display_sec.c secace.c secacl.c security_descriptor.c sddl.c privileges.c security_token.c access_check.c object_tree.c create_descriptor.c util_sid.c session.c',
+                  source='dom_sid.c display_sec.c secace.c secacl.c security_descriptor.c sddl.c privileges.c security_token.c access_check.c object_tree.c create_descriptor.c util_sid.c session.c secdesc.c',
                   private_library=True,
                   deps='talloc ndr NDR_SECURITY'
                   )