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Diffstat (limited to '')
| -rw-r--r-- | source4/dsdb/common/util_groups.c | 199 |
1 files changed, 199 insertions, 0 deletions
diff --git a/source4/dsdb/common/util_groups.c b/source4/dsdb/common/util_groups.c new file mode 100644 index 0000000..c2075de --- /dev/null +++ b/source4/dsdb/common/util_groups.c @@ -0,0 +1,199 @@ +/* + Unix SMB/CIFS implementation. + Password and authentication handling + Copyright (C) Andrew Bartlett <abartlet@samba.org> 2001-2010 + Copyright (C) Stefan Metzmacher 2005 + Copyright (C) Matthias Dieter Wallnöfer 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/>. +*/ + +#include "includes.h" +#include "auth/auth.h" +#include <ldb.h> +#include "dsdb/samdb/samdb.h" +#include "libcli/security/security.h" +#include "dsdb/common/util.h" + +/* This function tests if a SID structure "sids" contains the SID "sid" */ +static bool sids_contains_sid(const struct dom_sid *sids, + const unsigned int num_sids, + const struct dom_sid *sid) +{ + unsigned int i; + + for (i = 0; i < num_sids; i++) { + if (dom_sid_equal(&sids[i], sid)) + return true; + } + return false; +} + +/* + * This function generates the transitive closure of a given SAM object "dn_val" + * (it basically expands nested memberships). + * If the object isn't located in the "res_sids" structure yet and the + * "only_childs" flag is false, we add it to "res_sids". + * Then we've always to consider the "memberOf" attributes. We invoke the + * function recursively on each of it with the "only_childs" flag set to + * "false". + * The "only_childs" flag is particularly useful if you have a user object and + * want to include all it's groups (referenced with "memberOf") but not itself + * or considering if that object matches the filter. + * + * At the beginning "res_sids" should reference to a NULL pointer. + */ +NTSTATUS dsdb_expand_nested_groups(struct ldb_context *sam_ctx, + struct ldb_val *dn_val, const bool only_childs, const char *filter, + TALLOC_CTX *res_sids_ctx, struct dom_sid **res_sids, + unsigned int *num_res_sids) +{ + const char * const attrs[] = { "memberOf", NULL }; + unsigned int i; + int ret; + bool already_there; + struct ldb_dn *dn; + struct dom_sid sid; + TALLOC_CTX *tmp_ctx; + struct ldb_result *res; + NTSTATUS status; + const struct ldb_message_element *el; + + if (*res_sids == NULL) { + *num_res_sids = 0; + } + + if (!sam_ctx) { + DEBUG(0, ("No SAM available, cannot determine local groups\n")); + return NT_STATUS_INVALID_SYSTEM_SERVICE; + } + + tmp_ctx = talloc_new(res_sids_ctx); + + dn = ldb_dn_from_ldb_val(tmp_ctx, sam_ctx, dn_val); + if (dn == NULL) { + talloc_free(tmp_ctx); + DEBUG(0, (__location__ ": we failed parsing DN %.*s, so we cannot calculate the group token\n", + (int)dn_val->length, dn_val->data)); + return NT_STATUS_INTERNAL_DB_CORRUPTION; + } + + status = dsdb_get_extended_dn_sid(dn, &sid, "SID"); + if (NT_STATUS_EQUAL(status, NT_STATUS_OBJECT_NAME_NOT_FOUND)) { + /* If we fail finding a SID then this is no error since it could + * be a non SAM object - e.g. a group with object class + * "groupOfNames" */ + talloc_free(tmp_ctx); + return NT_STATUS_OK; + } else if (!NT_STATUS_IS_OK(status)) { + DEBUG(0, (__location__ ": when parsing DN '%s' we failed to parse it's SID component, so we cannot calculate the group token: %s\n", + ldb_dn_get_extended_linearized(tmp_ctx, dn, 1), + nt_errstr(status))); + talloc_free(tmp_ctx); + return status; + } + + if (!ldb_dn_minimise(dn)) { + talloc_free(tmp_ctx); + return NT_STATUS_INTERNAL_DB_CORRUPTION; + } + + if (only_childs) { + ret = dsdb_search_dn(sam_ctx, tmp_ctx, &res, dn, attrs, + DSDB_SEARCH_SHOW_EXTENDED_DN); + } else { + /* This is an O(n^2) linear search */ + already_there = sids_contains_sid(*res_sids, + *num_res_sids, &sid); + if (already_there) { + talloc_free(tmp_ctx); + return NT_STATUS_OK; + } + + ret = dsdb_search(sam_ctx, tmp_ctx, &res, dn, LDB_SCOPE_BASE, + attrs, DSDB_SEARCH_SHOW_EXTENDED_DN, "%s", + filter); + } + + /* + * We have the problem with the caller creating a <SID=S-....> + * DN for ForeignSecurityPrincipals as they also have + * duplicate objects with the SAME SID under CN=Configuration. + * This causes a SID= DN to fail with NO_SUCH_OBJECT on Samba + * and on Windows. So, we allow this to fail, and + * double-check if we can find it with a search in the main + * domain partition. + */ + if (ret == LDB_ERR_NO_SUCH_OBJECT && only_childs) { + char *sid_string = dom_sid_string(tmp_ctx, + &sid); + if (!sid_string) { + talloc_free(tmp_ctx); + return NT_STATUS_OK; + } + + ret = dsdb_search(sam_ctx, tmp_ctx, &res, + ldb_get_default_basedn(sam_ctx), + LDB_SCOPE_SUBTREE, + attrs, DSDB_SEARCH_SHOW_EXTENDED_DN, + "(&(objectClass=foreignSecurityPrincipal)(objectSID=%s))", + sid_string); + } + + if (ret == LDB_ERR_NO_SUCH_OBJECT) { + talloc_free(tmp_ctx); + return NT_STATUS_OK; + } + + if (ret != LDB_SUCCESS) { + DEBUG(1, (__location__ ": dsdb_search for %s failed: %s\n", + ldb_dn_get_extended_linearized(tmp_ctx, dn, 1), + ldb_errstring(sam_ctx))); + talloc_free(tmp_ctx); + return NT_STATUS_INTERNAL_DB_CORRUPTION; + } + + /* We may get back 0 results, if the SID didn't match the filter - such as it wasn't a domain group, for example */ + if (res->count != 1) { + talloc_free(tmp_ctx); + return NT_STATUS_OK; + } + + /* We only apply this test once we know the SID matches the filter */ + if (!only_childs) { + *res_sids = talloc_realloc(res_sids_ctx, *res_sids, + struct dom_sid, *num_res_sids + 1); + if (*res_sids == NULL) { + TALLOC_FREE(tmp_ctx); + return NT_STATUS_NO_MEMORY; + } + (*res_sids)[*num_res_sids] = sid; + ++(*num_res_sids); + } + + el = ldb_msg_find_element(res->msgs[0], "memberOf"); + + for (i = 0; el && i < el->num_values; i++) { + status = dsdb_expand_nested_groups(sam_ctx, &el->values[i], + false, filter, res_sids_ctx, res_sids, num_res_sids); + if (!NT_STATUS_IS_OK(status)) { + talloc_free(tmp_ctx); + return status; + } + } + + talloc_free(tmp_ctx); + + return NT_STATUS_OK; +} |