librpc:idl: Make netlogon_samlogon_response public

[Samba.git] / libcli / security / create_descriptor.c

/*
   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 "replace.h"
#include "lib/util/debug.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 downgrade 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;
}