/* 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" /* 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 bool contains_inheritable_aces(struct security_acl *acl) { int i; if (!acl) return false; 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)) return true; } return false; } static struct security_acl *preprocess_creator_acl(TALLOC_CTX *mem, struct security_acl *acl) { int i; struct security_acl *new_acl = talloc_zero(mem, struct security_acl); new_acl->revision = acl->revision; for (i=0; i < acl->num_aces; i++) { struct security_ace *ace = &acl->aces[i]; if (!(ace->flags & SEC_ACE_FLAG_INHERITED_ACE)){ new_acl->aces = talloc_realloc(new_acl, new_acl->aces, struct security_ace, new_acl->num_aces+1); if (new_acl->aces == NULL) { talloc_free(new_acl); return NULL; } new_acl->aces[new_acl->num_aces] = *ace; /*memcpy(&new_acl->aces[new_acl->num_aces], ace, sizeof(struct security_ace)); */ new_acl->num_aces++; } } if (new_acl) new_acl->revision = acl->revision; /* Todo what to do if all were inherited and this is empty */ return new_acl; } /* This is not exactly as described in the docs. The original seemed to return * only a list of the inherited or flagless ones... */ static bool postprocess_acl(struct security_acl *acl, struct dom_sid *owner, struct dom_sid *group, uint32_t (*generic_map)(uint32_t access_mask)) { int i; struct dom_sid *co, *cg; TALLOC_CTX *tmp_ctx = talloc_new(acl); if (!generic_map){ return false; } 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 == 0 || ace->flags & SEC_ACE_FLAG_INHERITED_ACE)) continue; if (ace->flags & SEC_ACE_FLAG_INHERIT_ONLY) continue; if (dom_sid_equal(&ace->trustee, co)){ ace->trustee = *owner; /* perhaps this should be done somewhere else? */ ace->flags &= ~SEC_ACE_FLAG_CONTAINER_INHERIT; } if (dom_sid_equal(&ace->trustee, cg)){ ace->trustee = *group; ace->flags &= ~SEC_ACE_FLAG_CONTAINER_INHERIT; } ace->access_mask = generic_map(ace->access_mask); } talloc_free(tmp_ctx); return true; } static struct security_acl *calculate_inherited_from_parent(TALLOC_CTX *mem_ctx, struct security_acl *acl, bool is_container, 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 *inh_acl = talloc_zero(tmp_ctx, struct security_acl); struct security_acl *new_acl; struct dom_sid *co, *cg; if (!tmp_acl || !inh_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_INHERIT_ONLY) continue; 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->num_aces++; } } if (is_container){ for (i=0; i < acl->num_aces; i++){ struct security_ace *ace = &acl->aces[i]; if (ace->flags & SEC_ACE_FLAG_NO_PROPAGATE_INHERIT) continue; if (!dom_sid_equal(&ace->trustee, co) && !dom_sid_equal(&ace->trustee, cg)) continue; if ((ace->flags & SEC_ACE_FLAG_CONTAINER_INHERIT) || (ace->flags & SEC_ACE_FLAG_OBJECT_INHERIT)){ inh_acl->aces = talloc_realloc(inh_acl, inh_acl->aces, struct security_ace, inh_acl->num_aces+1); if (inh_acl->aces == NULL){ talloc_free(tmp_ctx); return NULL; } inh_acl->aces[inh_acl->num_aces] = *ace; inh_acl->aces[inh_acl->num_aces].flags |= SEC_ACE_FLAG_INHERIT_ONLY; inh_acl->aces[inh_acl->num_aces].flags |= SEC_ACE_FLAG_INHERITED_ACE; inh_acl->num_aces++; } } } new_acl = security_acl_concatenate(mem_ctx,tmp_acl, inh_acl); if (new_acl) new_acl->revision = acl->revision; talloc_free(tmp_ctx); return new_acl; } /* In the docs this looks == calculate_inherited_from_parent. However, * It shouldn't return the inherited, rather filter them out.... */ static struct security_acl *calculate_inherited_from_creator(TALLOC_CTX *mem_ctx, struct security_acl *acl, bool is_container, 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 *inh_acl = talloc_zero(tmp_ctx, struct security_acl); */ struct security_acl *new_acl; struct dom_sid *co, *cg; if (!tmp_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_INHERITED_ACE) 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 = 0; 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); talloc_free(tmp_ctx); return new_acl; } static bool compute_acl(int acl_type, 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 *p_acl = NULL, *c_acl = NULL, **new_acl; if (acl_type == SEC_DESC_DACL_PRESENT){ if (parent_sd) p_acl = parent_sd->dacl; if (creator_sd) c_acl = creator_sd->dacl; new_acl = &new_sd->dacl; } else{ if (parent_sd) p_acl = parent_sd->sacl; if (creator_sd) c_acl = creator_sd->sacl; new_acl = &new_sd->sacl; } if (contains_inheritable_aces(p_acl)){ if (!c_acl || (c_acl && inherit_flags & SEC_DEFAULT_DESCRIPTOR)){ *new_acl = calculate_inherited_from_parent(new_sd, p_acl, is_container, object_list); if (*new_acl == NULL) goto final; if (!postprocess_acl(*new_acl, new_sd->owner_sid, new_sd->group_sid, generic_map)) return false; else goto final; } if (c_acl && !(inherit_flags & SEC_DEFAULT_DESCRIPTOR)){ struct security_acl *pr_acl, *tmp_acl, *tpr_acl; tpr_acl = preprocess_creator_acl(new_sd, c_acl); tmp_acl = calculate_inherited_from_creator(new_sd, tpr_acl, is_container, object_list); /* Todo some refactoring here! */ if (acl_type == SEC_DESC_DACL_PRESENT && !(creator_sd->type & SECINFO_PROTECTED_DACL) && (inherit_flags & SEC_DACL_AUTO_INHERIT)){ pr_acl = calculate_inherited_from_parent(new_sd, p_acl, is_container, object_list); *new_acl = security_acl_concatenate(new_sd, tmp_acl, pr_acl); new_sd->type |= SEC_DESC_DACL_AUTO_INHERITED; } else if (acl_type == SEC_DESC_SACL_PRESENT && !(creator_sd->type & SECINFO_PROTECTED_SACL) && (inherit_flags & SEC_SACL_AUTO_INHERIT)){ pr_acl = calculate_inherited_from_parent(new_sd, p_acl, is_container, object_list); *new_acl = security_acl_concatenate(new_sd, tmp_acl, pr_acl); new_sd->type |= SEC_DESC_SACL_AUTO_INHERITED; } } if (*new_acl == NULL) goto final; if (!postprocess_acl(*new_acl, new_sd->owner_sid, new_sd->group_sid,generic_map)) return false; else goto final; } else{ if (!c_acl){ if (acl_type == SEC_DESC_DACL_PRESENT && token->default_dacl) *new_acl = security_acl_dup(new_sd, token->default_dacl); } else{ *new_acl = preprocess_creator_acl(new_sd,c_acl); if (*new_acl == NULL) goto final; if (!postprocess_acl(*new_acl, new_sd->owner_sid, new_sd->group_sid,generic_map)) return false; else goto final; } } final: if (acl_type == SEC_DESC_DACL_PRESENT && new_sd->dacl) new_sd->type |= SEC_DESC_DACL_PRESENT; if (acl_type == SEC_DESC_SACL_PRESENT && new_sd->sacl) new_sd->type |= SEC_DESC_SACL_PRESENT; /* 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; 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) new_owner = parent_sd->owner_sid; else if (!default_owner) new_owner = token->user_sid; else new_owner = default_owner; } 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) new_group = token->group_sid; else new_group = default_group; } 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(SEC_DESC_DACL_PRESENT, parent_sd, creator_sd, is_container, inherit_flags, object_list, generic_map,token,new_sd)){ talloc_free(new_sd); return NULL; } if (!compute_acl(SEC_DESC_SACL_PRESENT, parent_sd, creator_sd, is_container, inherit_flags, object_list, generic_map, token,new_sd)){ talloc_free(new_sd); return NULL; } return new_sd; }