From 6283f2caaa42c7238bdc9c2e8bc1246207645019 Mon Sep 17 00:00:00 2001 From: Nadezhda Ivanova Date: Sun, 20 Sep 2009 13:50:34 -0700 Subject: Initial implementation of security descriptor creation in DS TODO's: ACE sorting and clarifying the inheritance of object specific ace's. --- source4/libcli/security/create_descriptor.c | 352 +++++++++++++++++++++++++++- 1 file changed, 348 insertions(+), 4 deletions(-) (limited to 'source4/libcli') diff --git a/source4/libcli/security/create_descriptor.c b/source4/libcli/security/create_descriptor.c index 6a928273b7..1054479f28 100644 --- a/source4/libcli/security/create_descriptor.c +++ b/source4/libcli/security/create_descriptor.c @@ -29,6 +29,18 @@ #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 @@ -63,6 +75,328 @@ uint32_t map_generic_rights_ds(uint32_t access_mask) 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, @@ -108,10 +442,20 @@ struct security_descriptor *create_security_descriptor(TALLOC_CTX *mem_ctx, talloc_free(new_sd); return NULL; } - /* Todo remove */ - if (creator_sd && creator_sd->type & SEC_DESC_DACL_PRESENT){ - new_sd->dacl = security_acl_dup(new_sd, creator_sd->dacl); - new_sd->type |= SEC_DESC_DACL_PRESENT; + + 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; } -- cgit