Adding upstream version 2:4.17.12+dfsg.upstream/2%4.17.12+dfsgupstream

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 631 insertions, 0 deletions

diff --git a/libcli/security/create_descriptor.c b/libcli/security/create_descriptor.c
new file mode 100644
index 0000000..947d6c1
--- /dev/null
+++ b/libcli/security/create_descriptor.c
@@ -0,0 +1,631 @@
+/*
+   Copyright (C) Nadezhda Ivanova 2009
+
+   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/>.
+*/
+
+/*
+ *  Name: create_descriptor
+ *
+ *  Component: routines for calculating and creating security descriptors
+ *  as described in MS-DTYP 2.5.3.x
+ *
+ *  Description:
+ *
+ *
+ *  Author: Nadezhda Ivanova
+ */
+#include "includes.h"
+#include "libcli/security/security.h"
+#include "librpc/gen_ndr/ndr_security.h"
+
+/* Todos:
+ * build the security token dacl as follows:
+ * SYSTEM: GA, OWNER: GA, LOGIN_SID:GW|GE
+ * Need session id information for the login SID. Probably
+ * the best place for this is during token creation
+ *
+ * Implement SD Invariants
+ * ACE sorting rules
+ * LDAP_SERVER_SD_FLAGS_OID control
+ * ADTS 7.1.3.3 needs to be clarified
+ */
+
+/* the mapping function for generic rights for DS.(GA,GR,GW,GX)
+ * The mapping function is passed as an argument to the
+ * descriptor calculating routine and depends on the security
+ * manager that calls the calculating routine.
+ * TODO: need similar mappings for the file system and
+ * registry security managers in order to make this code
+ * generic for all security managers
+ */
+
+uint32_t map_generic_rights_ds(uint32_t access_mask)
+{
+	if (access_mask & SEC_GENERIC_ALL) {
+		access_mask |= SEC_ADS_GENERIC_ALL;
+		access_mask &= ~SEC_GENERIC_ALL;
+	}
+
+	if (access_mask & SEC_GENERIC_EXECUTE) {
+		access_mask |= SEC_ADS_GENERIC_EXECUTE;
+		access_mask &= ~SEC_GENERIC_EXECUTE;
+	}
+
+	if (access_mask & SEC_GENERIC_WRITE) {
+		access_mask |= SEC_ADS_GENERIC_WRITE;
+		access_mask &= ~SEC_GENERIC_WRITE;
+	}
+
+	if (access_mask & SEC_GENERIC_READ) {
+		access_mask |= SEC_ADS_GENERIC_READ;
+		access_mask &= ~SEC_GENERIC_READ;
+	}
+
+	return access_mask;
+}
+
+/* Not sure what this has to be,
+* and it does not seem to have any influence */
+static bool object_in_list(const struct GUID *object_list, const struct GUID *object)
+{
+	size_t i;
+
+	if (object_list == NULL) {
+		return true;
+	}
+
+	if (GUID_all_zero(object)) {
+		return true;
+	}
+
+	for (i=0; ; i++) {
+		if (GUID_all_zero(&object_list[i])) {
+			return false;
+		}
+		if (!GUID_equal(&object_list[i], object)) {
+			continue;
+		}
+
+		return true;
+	}
+
+	return false;
+}
+
+/* returns true if the ACE gontains generic information
+ * that needs to be processed additionally */
+ 
+static bool desc_ace_has_generic(const struct security_ace *ace)
+{
+	if (ace->access_mask & SEC_GENERIC_ALL || ace->access_mask & SEC_GENERIC_READ ||
+	    ace->access_mask & SEC_GENERIC_WRITE || ace->access_mask & SEC_GENERIC_EXECUTE) {
+		return true;
+	}
+	if (dom_sid_equal(&ace->trustee, &global_sid_Creator_Owner) ||
+	    dom_sid_equal(&ace->trustee, &global_sid_Creator_Group)) {
+		return true;
+	}
+	return false;
+}
+
+/* creates an ace in which the generic information is expanded */
+
+static void desc_expand_generic(struct security_ace *new_ace,
+				struct dom_sid *owner,
+				struct dom_sid *group)
+{
+	new_ace->access_mask = map_generic_rights_ds(new_ace->access_mask);
+	if (dom_sid_equal(&new_ace->trustee, &global_sid_Creator_Owner)) {
+		new_ace->trustee = *owner;
+	}
+	if (dom_sid_equal(&new_ace->trustee, &global_sid_Creator_Group)) {
+		new_ace->trustee = *group;
+	}
+	new_ace->flags = 0x0;
+}
+
+static struct security_acl *calculate_inherited_from_parent(TALLOC_CTX *mem_ctx,
+							    struct security_acl *acl,
+							    bool is_container,
+							    struct dom_sid *owner,
+							    struct dom_sid *group,
+							    struct GUID *object_list)
+{
+	uint32_t i;
+	TALLOC_CTX *tmp_ctx = talloc_new(mem_ctx);
+	struct security_acl *tmp_acl = talloc_zero(mem_ctx, struct security_acl);
+	if (!tmp_acl) {
+		return NULL;
+	}
+
+	if (!acl) {
+		return NULL;
+	}
+
+	for (i=0; i < acl->num_aces; i++) {
+		const struct security_ace *ace = &acl->aces[i];
+		const struct GUID *inherited_object = NULL;
+		const struct GUID *inherited_property = NULL;
+		struct security_ace *tmp_ace = NULL;
+		bool applies = false;
+		bool inherited_only = false;
+		bool expand_ace = false;
+		bool expand_only = false;
+
+		if (is_container && (ace->flags & SEC_ACE_FLAG_CONTAINER_INHERIT)) {
+			applies = true;
+		} else if (!is_container && (ace->flags & SEC_ACE_FLAG_OBJECT_INHERIT)) {
+			applies = true;
+		}
+
+		if (!applies) {
+			/*
+			 * If the ace doesn't apply to the
+			 * current node, we should only keep
+			 * it as SEC_ACE_FLAG_OBJECT_INHERIT
+			 * on a container. We'll add
+			 * SEC_ACE_FLAG_INHERITED_ACE
+			 * and SEC_ACE_FLAG_INHERIT_ONLY below.
+			 *
+			 * Otherwise we should completely ignore it.
+			 */
+			if (!(ace->flags & SEC_ACE_FLAG_OBJECT_INHERIT)) {
+				continue;
+			}
+		}
+
+		switch (ace->type) {
+		case SEC_ACE_TYPE_ACCESS_ALLOWED:
+		case SEC_ACE_TYPE_ACCESS_DENIED:
+		case SEC_ACE_TYPE_SYSTEM_AUDIT:
+		case SEC_ACE_TYPE_SYSTEM_ALARM:
+		case SEC_ACE_TYPE_ALLOWED_COMPOUND:
+			break;
+
+		case SEC_ACE_TYPE_ACCESS_ALLOWED_OBJECT:
+		case SEC_ACE_TYPE_ACCESS_DENIED_OBJECT:
+		case SEC_ACE_TYPE_SYSTEM_ALARM_OBJECT:
+		case SEC_ACE_TYPE_SYSTEM_AUDIT_OBJECT:
+			if (ace->object.object.flags & SEC_ACE_OBJECT_TYPE_PRESENT) {
+				inherited_property = &ace->object.object.type.type;
+			}
+			if (ace->object.object.flags & SEC_ACE_INHERITED_OBJECT_TYPE_PRESENT) {
+				inherited_object = &ace->object.object.inherited_type.inherited_type;
+			}
+
+			if (inherited_object != NULL && !object_in_list(object_list, inherited_object)) {
+				/*
+				 * An explicit object class schemaId is given,
+				 * but doesn't belong to the current object.
+				 */
+				applies = false;
+			}
+
+			break;
+		}
+
+		if (ace->flags & SEC_ACE_FLAG_NO_PROPAGATE_INHERIT) {
+			if (!applies) {
+				/*
+				 * If the ACE doesn't apply to
+				 * the current object, we should
+				 * ignore it as it should not be
+				 * inherited any further
+				 */
+				continue;
+			}
+			/*
+			 * We should only keep the expanded version
+			 * of the ACE on the current object.
+			 */
+			expand_ace = true;
+			expand_only = true;
+		} else if (applies) {
+			/*
+			 * We check if should also add
+			 * the expanded version of the ACE
+			 * in addition, in case we should
+			 * expand generic access bits or
+			 * special sids.
+			 *
+			 * In that case we need to
+			 * keep the original ACE with
+			 * SEC_ACE_FLAG_INHERIT_ONLY.
+			 */
+			expand_ace = desc_ace_has_generic(ace);
+			if (expand_ace) {
+				inherited_only = true;
+			}
+		} else {
+			/*
+			 * If the ACE doesn't apply
+			 * to the current object,
+			 * we need to keep it with
+			 * SEC_ACE_FLAG_INHERIT_ONLY
+			 * in order to apply them to
+			 * grandchildren
+			 */
+			inherited_only = true;
+		}
+
+		if (expand_ace) {
+			tmp_acl->aces = talloc_realloc(tmp_acl,
+						       tmp_acl->aces,
+						       struct security_ace,
+						       tmp_acl->num_aces+1);
+			if (tmp_acl->aces == NULL) {
+				talloc_free(tmp_ctx);
+				return NULL;
+			}
+
+			tmp_ace = &tmp_acl->aces[tmp_acl->num_aces];
+			tmp_acl->num_aces++;
+
+			*tmp_ace = *ace;
+
+			/*
+			 * Expand generic access bits as well as special
+			 * sids.
+			 */
+			desc_expand_generic(tmp_ace, owner, group);
+
+			/*
+			 * Expanded ACEs are marked as inherited,
+			 * but never inherited any further to
+			 * grandchildren.
+			 */
+			tmp_ace->flags |= SEC_ACE_FLAG_INHERITED_ACE;
+			tmp_ace->flags &= ~SEC_ACE_FLAG_CONTAINER_INHERIT;
+			tmp_ace->flags &= ~SEC_ACE_FLAG_OBJECT_INHERIT;
+			tmp_ace->flags &= ~SEC_ACE_FLAG_NO_PROPAGATE_INHERIT;
+
+			/*
+			 * Expanded ACEs never have an explicit
+			 * object class schemaId, so clear it
+			 * if present.
+			 */
+			if (inherited_object != NULL) {
+				tmp_ace->object.object.flags &= ~SEC_ACE_INHERITED_OBJECT_TYPE_PRESENT;
+			}
+
+			/*
+			 * If the ACE had an explicit object class
+			 * schemaId, but no attribute/propertySet
+			 * we need to downgrate the _OBJECT variants
+			 * to the normal ones.
+			 */
+			if (inherited_property == NULL) {
+				switch (tmp_ace->type) {
+				case SEC_ACE_TYPE_ACCESS_ALLOWED:
+				case SEC_ACE_TYPE_ACCESS_DENIED:
+				case SEC_ACE_TYPE_SYSTEM_AUDIT:
+				case SEC_ACE_TYPE_SYSTEM_ALARM:
+				case SEC_ACE_TYPE_ALLOWED_COMPOUND:
+					break;
+				case SEC_ACE_TYPE_ACCESS_ALLOWED_OBJECT:
+					tmp_ace->type = SEC_ACE_TYPE_ACCESS_ALLOWED;
+					break;
+				case SEC_ACE_TYPE_ACCESS_DENIED_OBJECT:
+					tmp_ace->type = SEC_ACE_TYPE_ACCESS_DENIED;
+					break;
+				case SEC_ACE_TYPE_SYSTEM_ALARM_OBJECT:
+					tmp_ace->type = SEC_ACE_TYPE_SYSTEM_ALARM;
+					break;
+				case SEC_ACE_TYPE_SYSTEM_AUDIT_OBJECT:
+					tmp_ace->type = SEC_ACE_TYPE_SYSTEM_AUDIT;
+					break;
+				}
+			}
+
+			if (expand_only) {
+				continue;
+			}
+		}
+
+		tmp_acl->aces = talloc_realloc(tmp_acl,
+					       tmp_acl->aces,
+					       struct security_ace,
+					       tmp_acl->num_aces+1);
+		if (tmp_acl->aces == NULL) {
+			talloc_free(tmp_ctx);
+			return NULL;
+		}
+
+		tmp_ace = &tmp_acl->aces[tmp_acl->num_aces];
+		tmp_acl->num_aces++;
+
+		*tmp_ace = *ace;
+		tmp_ace->flags |= SEC_ACE_FLAG_INHERITED_ACE;
+
+		if (inherited_only) {
+			tmp_ace->flags |= SEC_ACE_FLAG_INHERIT_ONLY;
+		} else {
+			tmp_ace->flags &= ~SEC_ACE_FLAG_INHERIT_ONLY;
+		}
+
+		if (ace->flags & SEC_ACE_FLAG_NO_PROPAGATE_INHERIT) {
+			tmp_ace->flags &= ~SEC_ACE_FLAG_CONTAINER_INHERIT;
+			tmp_ace->flags &= ~SEC_ACE_FLAG_OBJECT_INHERIT;
+			tmp_ace->flags &= ~SEC_ACE_FLAG_NO_PROPAGATE_INHERIT;
+		}
+	}
+	if (tmp_acl->num_aces == 0) {
+		return NULL;
+	}
+	if (acl) {
+		tmp_acl->revision = acl->revision;
+	}
+	return tmp_acl;
+}
+
+static struct security_acl *process_user_acl(TALLOC_CTX *mem_ctx,
+					     struct security_acl *acl,
+					     bool is_container,
+					     struct dom_sid *owner,
+					     struct dom_sid *group,
+					     struct GUID *object_list,
+					     bool is_protected)
+{
+	uint32_t i;
+	TALLOC_CTX *tmp_ctx = talloc_new(mem_ctx);
+	struct security_acl *tmp_acl = talloc_zero(tmp_ctx, struct security_acl);
+	struct security_acl *new_acl;
+
+	if (!acl)
+		return NULL;
+
+	if (!tmp_acl)
+		return NULL;
+
+	tmp_acl->revision = acl->revision;
+	DBG_DEBUG("acl revision %d\n", acl->revision);
+
+	for (i=0; i < acl->num_aces; i++){
+		struct security_ace *ace = &acl->aces[i];
+		/* Remove ID flags from user-provided ACEs
+		 * if we break inheritance, ignore them otherwise */
+		if (ace->flags & SEC_ACE_FLAG_INHERITED_ACE) {
+			if (is_protected) {
+				ace->flags &= ~SEC_ACE_FLAG_INHERITED_ACE;
+			} else {
+				continue;
+			}
+		}
+
+		if (ace->flags & SEC_ACE_FLAG_INHERIT_ONLY &&
+		    !(ace->flags & SEC_ACE_FLAG_CONTAINER_INHERIT ||
+		      ace->flags & SEC_ACE_FLAG_OBJECT_INHERIT))
+			continue;
+
+		tmp_acl->aces = talloc_realloc(tmp_acl,
+					       tmp_acl->aces,
+					       struct security_ace,
+					       tmp_acl->num_aces+1);
+		tmp_acl->aces[tmp_acl->num_aces] = *ace;
+		tmp_acl->num_aces++;
+		if (ace->flags & SEC_ACE_FLAG_INHERIT_ONLY) {
+			continue;
+		}
+		/* if the ACE contains CO, CG, GA, GE, GR or GW, and is inheritable
+		 * it has to be expanded to two aces, the original as IO,
+		 * and another one where these are translated */
+		if (desc_ace_has_generic(ace)) {
+			if (!(ace->flags & SEC_ACE_FLAG_CONTAINER_INHERIT)) {
+				desc_expand_generic(&tmp_acl->aces[tmp_acl->num_aces-1],
+						    owner,
+						    group);
+			} else {
+				/*The original ACE becomes read only */
+				tmp_acl->aces[tmp_acl->num_aces-1].flags |= SEC_ACE_FLAG_INHERIT_ONLY;
+				tmp_acl->aces = talloc_realloc(tmp_acl, tmp_acl->aces,
+							       struct security_ace,
+							       tmp_acl->num_aces+1);
+				/* add a new ACE with expanded generic info */
+				tmp_acl->aces[tmp_acl->num_aces] = *ace;
+				desc_expand_generic(&tmp_acl->aces[tmp_acl->num_aces],
+						    owner,
+						    group);
+				tmp_acl->num_aces++;
+			}
+		}
+	}
+	new_acl = security_acl_dup(mem_ctx,tmp_acl);
+
+	if (new_acl)
+		new_acl->revision = acl->revision;
+
+	talloc_free(tmp_ctx);
+	return new_acl;
+}
+
+static void cr_descr_log_descriptor(struct security_descriptor *sd,
+				    const char *message,
+				    int level)
+{
+	if (sd) {
+		DEBUG(level,("%s: %s\n", message,
+			     ndr_print_struct_string(0,(ndr_print_fn_t)ndr_print_security_descriptor,
+						     "", sd)));
+	}
+	else {
+		DEBUG(level,("%s: NULL\n", message));
+	}
+}
+
+#if 0
+static void cr_descr_log_acl(struct security_acl *acl,
+				    const char *message,
+				    int level)
+{
+	if (acl) {
+		DEBUG(level,("%s: %s\n", message,
+			     ndr_print_struct_string(0,(ndr_print_fn_t)ndr_print_security_acl,
+						     "", acl)));
+	}
+	else {
+		DEBUG(level,("%s: NULL\n", message));
+	}
+}
+#endif
+
+static bool compute_acl(struct security_descriptor *parent_sd,
+			struct security_descriptor *creator_sd,
+			bool is_container,
+			uint32_t inherit_flags,
+			struct GUID *object_list,
+			uint32_t (*generic_map)(uint32_t access_mask),
+			struct security_token *token,
+			struct security_descriptor *new_sd) /* INOUT argument */
+{
+	struct security_acl *user_dacl, *user_sacl, *inherited_dacl, *inherited_sacl;
+	int level = 10;
+
+	if (!parent_sd || !(inherit_flags & SEC_DACL_AUTO_INHERIT)) {
+		inherited_dacl = NULL;
+	} else if (creator_sd && (creator_sd->type & SEC_DESC_DACL_PROTECTED)) {
+		inherited_dacl = NULL;
+	} else {
+		inherited_dacl = calculate_inherited_from_parent(new_sd,
+								 parent_sd->dacl,
+								 is_container,
+								 new_sd->owner_sid,
+								 new_sd->group_sid,
+								 object_list);
+	}
+
+
+	if (!parent_sd || !(inherit_flags & SEC_SACL_AUTO_INHERIT)) {
+		inherited_sacl = NULL;
+	} else if (creator_sd && (creator_sd->type & SEC_DESC_SACL_PROTECTED)) {
+		inherited_sacl = NULL;
+	} else {
+		inherited_sacl = calculate_inherited_from_parent(new_sd,
+								 parent_sd->sacl,
+								 is_container,
+								 new_sd->owner_sid,
+								 new_sd->group_sid,
+								 object_list);
+	}
+
+	if (!creator_sd || (inherit_flags & SEC_DEFAULT_DESCRIPTOR)) {
+		user_dacl = NULL;
+		user_sacl = NULL;
+	} else {
+		user_dacl = process_user_acl(new_sd,
+					     creator_sd->dacl,
+					     is_container,
+					     new_sd->owner_sid,
+					     new_sd->group_sid,
+					     object_list,
+					     creator_sd->type & SEC_DESC_DACL_PROTECTED);
+		user_sacl = process_user_acl(new_sd,
+					     creator_sd->sacl,
+					     is_container,
+					     new_sd->owner_sid,
+					     new_sd->group_sid,
+					     object_list,
+					     creator_sd->type & SEC_DESC_SACL_PROTECTED);
+	}
+	cr_descr_log_descriptor(parent_sd, __location__"parent_sd", level);
+	cr_descr_log_descriptor(creator_sd,__location__ "creator_sd", level);
+
+	new_sd->dacl = security_acl_concatenate(new_sd, user_dacl, inherited_dacl);
+	if (new_sd->dacl) {
+		new_sd->type |= SEC_DESC_DACL_PRESENT;
+	}
+	if (inherited_dacl) {
+		new_sd->type |= SEC_DESC_DACL_AUTO_INHERITED;
+	}
+
+	new_sd->sacl = security_acl_concatenate(new_sd, user_sacl, inherited_sacl);
+	if (new_sd->sacl) {
+		new_sd->type |= SEC_DESC_SACL_PRESENT;
+	}
+	if (inherited_sacl) {
+		new_sd->type |= SEC_DESC_SACL_AUTO_INHERITED;
+	}
+	/* This is a hack to handle the fact that
+	 * apprantly any AI flag provided by the user is preserved */
+	if (creator_sd)
+		new_sd->type |= creator_sd->type;
+	cr_descr_log_descriptor(new_sd, __location__"final sd", level);
+	return true;
+}
+
+struct security_descriptor *create_security_descriptor(TALLOC_CTX *mem_ctx,
+						       struct security_descriptor *parent_sd,
+						       struct security_descriptor *creator_sd,
+						       bool is_container,
+						       struct GUID *object_list,
+						       uint32_t inherit_flags,
+						       struct security_token *token,
+						       struct dom_sid *default_owner, /* valid only for DS, NULL for the other RSs */
+						       struct dom_sid *default_group, /* valid only for DS, NULL for the other RSs */
+						       uint32_t (*generic_map)(uint32_t access_mask))
+{
+	struct security_descriptor *new_sd;
+	struct dom_sid *new_owner = NULL;
+	struct dom_sid *new_group = NULL;
+
+	new_sd = security_descriptor_initialise(mem_ctx);
+	if (!new_sd) {
+		return NULL;
+	}
+
+	if (!creator_sd || !creator_sd->owner_sid) {
+		if ((inherit_flags & SEC_OWNER_FROM_PARENT) && parent_sd) {
+			new_owner = parent_sd->owner_sid;
+		} else if (!default_owner) {
+			new_owner = &token->sids[PRIMARY_USER_SID_INDEX];
+		} else {
+			new_owner = default_owner;
+			new_sd->type |= SEC_DESC_OWNER_DEFAULTED;
+		}
+	} else {
+		new_owner = creator_sd->owner_sid;
+	}
+
+	if (!creator_sd || !creator_sd->group_sid){
+		if ((inherit_flags & SEC_GROUP_FROM_PARENT) && parent_sd) {
+			new_group = parent_sd->group_sid;
+		} else if (!default_group && token->num_sids > PRIMARY_GROUP_SID_INDEX) {
+			new_group = &token->sids[PRIMARY_GROUP_SID_INDEX];
+		} else if (!default_group) {
+			/* This will happen only for anonymous, which has no other groups */
+			new_group = &token->sids[PRIMARY_USER_SID_INDEX];
+		} else {
+			new_group = default_group;
+			new_sd->type |= SEC_DESC_GROUP_DEFAULTED;
+		}
+	} else {
+		new_group = creator_sd->group_sid;
+	}
+
+	new_sd->owner_sid = talloc_memdup(new_sd, new_owner, sizeof(struct dom_sid));
+	new_sd->group_sid = talloc_memdup(new_sd, new_group, sizeof(struct dom_sid));
+	if (!new_sd->owner_sid || !new_sd->group_sid){
+		talloc_free(new_sd);
+		return NULL;
+	}
+
+	if (!compute_acl(parent_sd, creator_sd,
+			 is_container, inherit_flags, object_list,
+			 generic_map,token,new_sd)){
+		talloc_free(new_sd);
+		return NULL;
+	}
+
+	return new_sd;
+}