/* 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 . */ /* * Name: create_descriptor * * Component: routines for calculating and creating security descriptors * as described in MS-DTYP 2.5.2.2 * * 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(struct GUID *object_list, struct GUID *object) { return true; } 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) { int i; TALLOC_CTX *tmp_ctx = talloc_new(mem_ctx); struct security_acl *tmp_acl = talloc_zero(mem_ctx, struct security_acl); struct dom_sid *co, *cg; if (!tmp_acl) { return NULL; } if (!acl) { return NULL; } co = dom_sid_parse_talloc(tmp_ctx, SID_CREATOR_OWNER); cg = dom_sid_parse_talloc(tmp_ctx, SID_CREATOR_GROUP); for (i=0; i < acl->num_aces; i++) { struct security_ace *ace = &acl->aces[i]; if ((ace->flags & SEC_ACE_FLAG_CONTAINER_INHERIT) || (ace->flags & SEC_ACE_FLAG_OBJECT_INHERIT)) { 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_acl->aces[tmp_acl->num_aces] = *ace; tmp_acl->aces[tmp_acl->num_aces].flags |= SEC_ACE_FLAG_INHERITED_ACE; if (is_container && (ace->flags & SEC_ACE_FLAG_OBJECT_INHERIT)) tmp_acl->aces[tmp_acl->num_aces].flags |= SEC_ACE_FLAG_INHERIT_ONLY; if (ace->type == SEC_ACE_TYPE_ACCESS_ALLOWED_OBJECT || ace->type == SEC_ACE_TYPE_ACCESS_DENIED_OBJECT) { if (!object_in_list(object_list, &ace->object.object.type.type)) { tmp_acl->aces[tmp_acl->num_aces].flags |= SEC_ACE_FLAG_INHERIT_ONLY; } } tmp_acl->aces[tmp_acl->num_aces].access_mask = map_generic_rights_ds(ace->access_mask); tmp_acl->num_aces++; if (is_container) { if (!(ace->flags & SEC_ACE_FLAG_NO_PROPAGATE_INHERIT) && ((dom_sid_equal(&ace->trustee, co) || dom_sid_equal(&ace->trustee, cg)))) { 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_acl->aces[tmp_acl->num_aces] = *ace; tmp_acl->aces[tmp_acl->num_aces].flags &= ~SEC_ACE_FLAG_INHERIT_ONLY; tmp_acl->aces[tmp_acl->num_aces].flags |= SEC_ACE_FLAG_INHERITED_ACE; if (dom_sid_equal(&tmp_acl->aces[tmp_acl->num_aces].trustee, co)) { tmp_acl->aces[tmp_acl->num_aces].trustee = *owner; } if (dom_sid_equal(&tmp_acl->aces[tmp_acl->num_aces].trustee, cg)) { tmp_acl->aces[tmp_acl->num_aces].trustee = *group; } tmp_acl->aces[tmp_acl->num_aces].flags &= ~SEC_ACE_FLAG_CONTAINER_INHERIT; tmp_acl->aces[tmp_acl->num_aces].access_mask = map_generic_rights_ds(ace->access_mask); tmp_acl->num_aces++; } } } } 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) { int 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; struct dom_sid *co, *cg; if (!acl) return NULL; if (!tmp_acl) return NULL; tmp_acl->revision = acl->revision; DEBUG(6,(__location__ ": acl revision %u\n", acl->revision)); co = dom_sid_parse_talloc(tmp_ctx, SID_CREATOR_OWNER); cg = dom_sid_parse_talloc(tmp_ctx, SID_CREATOR_GROUP); for (i=0; i < acl->num_aces; i++){ struct security_ace *ace = &acl->aces[i]; if (ace->flags & SEC_ACE_FLAG_INHERITED_ACE) 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; if (dom_sid_equal(&(tmp_acl->aces[tmp_acl->num_aces].trustee), co)) { tmp_acl->aces[tmp_acl->num_aces].trustee = *owner; tmp_acl->aces[tmp_acl->num_aces].flags &= ~SEC_ACE_FLAG_CONTAINER_INHERIT; } if (dom_sid_equal(&(tmp_acl->aces[tmp_acl->num_aces].trustee), cg)) { tmp_acl->aces[tmp_acl->num_aces].trustee = *group; tmp_acl->aces[tmp_acl->num_aces].flags &= ~SEC_ACE_FLAG_CONTAINER_INHERIT; } tmp_acl->aces[tmp_acl->num_aces].access_mask = map_generic_rights_ds(tmp_acl->aces[tmp_acl->num_aces].access_mask); tmp_acl->num_aces++; if (!dom_sid_equal(&ace->trustee, co) && !dom_sid_equal(&ace->trustee, cg)) 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->aces[tmp_acl->num_aces].flags |= SEC_ACE_FLAG_INHERIT_ONLY; 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)); } } 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)); } } 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); user_sacl = process_user_acl(new_sd, creator_sd->sacl, is_container, new_sd->owner_sid, new_sd->group_sid, object_list); } 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; }