diff options
Diffstat (limited to 'source4/winbind/idmap.c')
| -rw-r--r-- | source4/winbind/idmap.c | 1072 |
1 files changed, 1072 insertions, 0 deletions
diff --git a/source4/winbind/idmap.c b/source4/winbind/idmap.c new file mode 100644 index 0000000000..3372ad51ee --- /dev/null +++ b/source4/winbind/idmap.c @@ -0,0 +1,1072 @@ +/* + Unix SMB/CIFS implementation. + + Map SIDs to uids/gids and back + + Copyright (C) Kai Blin 2008 + + 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 "librpc/gen_ndr/lsa.h" +#include "librpc/gen_ndr/samr.h" +#include "librpc/gen_ndr/ndr_security.h" +#include "lib/ldb/include/ldb.h" +#include "lib/ldb/include/ldb_errors.h" +#include "lib/ldb_wrap.h" +#include "param/param.h" +#include "winbind/idmap.h" +#include "libcli/security/proto.h" +#include "libcli/ldap/ldap_ndr.h" + +/** + * Get uid/gid bounds from idmap database + * + * \param idmap_ctx idmap context to use + * \param low lower uid/gid bound is stored here + * \param high upper uid/gid bound is stored here + * \return 0 on success, nonzero on failure + */ +static int idmap_get_bounds(struct idmap_context *idmap_ctx, uint32_t *low, + uint32_t *high) +{ + int ret = -1; + struct ldb_context *ldb = idmap_ctx->ldb_ctx; + struct ldb_dn *dn; + struct ldb_result *res = NULL; + TALLOC_CTX *tmp_ctx = talloc_new(idmap_ctx); + uint32_t lower_bound = (uint32_t) -1; + uint32_t upper_bound = (uint32_t) -1; + + dn = ldb_dn_new(tmp_ctx, ldb, "CN=CONFIG"); + if (dn == NULL) goto failed; + + ret = ldb_search(ldb, dn, LDB_SCOPE_BASE, NULL, NULL, &res); + if (ret != LDB_SUCCESS) goto failed; + + talloc_steal(tmp_ctx, res); + + if (res->count != 1) { + ret = -1; + goto failed; + } + + lower_bound = ldb_msg_find_attr_as_uint(res->msgs[0], "lowerBound", -1); + if (lower_bound != (uint32_t) -1) { + ret = LDB_SUCCESS; + } else { + ret = -1; + goto failed; + } + + upper_bound = ldb_msg_find_attr_as_uint(res->msgs[0], "upperBound", -1); + if (upper_bound != (uint32_t) -1) { + ret = LDB_SUCCESS; + } else { + ret = -1; + } + +failed: + talloc_free(tmp_ctx); + *low = lower_bound; + *high = upper_bound; + return ret; +} + +/** + * Add a dom_sid structure to a ldb_message + * \param idmap_ctx idmap context to use + * \param mem_ctx talloc context to use + * \param ldb_message ldb message to add dom_sid to + * \param attr_name name of the attribute to store the dom_sid in + * \param sid dom_sid to store + * \return 0 on success, an ldb error code on failure. + */ +static int idmap_msg_add_dom_sid(struct idmap_context *idmap_ctx, + TALLOC_CTX *mem_ctx, struct ldb_message *msg, + const char *attr_name, const struct dom_sid *sid) +{ + struct ldb_val val; + enum ndr_err_code ndr_err; + + ndr_err = ndr_push_struct_blob(&val, mem_ctx, + lp_iconv_convenience(idmap_ctx->lp_ctx), + sid, + (ndr_push_flags_fn_t)ndr_push_dom_sid); + + if (!NDR_ERR_CODE_IS_SUCCESS(ndr_err)) { + return -1; + } + + return ldb_msg_add_value(msg, attr_name, &val, NULL); +} + +/** + * Get a dom_sid structure from a ldb message. + * + * \param mem_ctx talloc context to allocate dom_sid memory in + * \param msg ldb_message to get dom_sid from + * \param attr_name key that has the dom_sid as data + * \return dom_sid structure on success, NULL on failure + */ +static struct dom_sid *idmap_msg_get_dom_sid(TALLOC_CTX *mem_ctx, + struct ldb_message *msg, const char *attr_name) +{ + struct dom_sid *sid; + const struct ldb_val *val; + enum ndr_err_code ndr_err; + + val = ldb_msg_find_ldb_val(msg, attr_name); + if (val == NULL) { + return NULL; + } + + sid = talloc(mem_ctx, struct dom_sid); + if (sid == NULL) { + return NULL; + } + + ndr_err = ndr_pull_struct_blob(val, sid, NULL, sid, + (ndr_pull_flags_fn_t)ndr_pull_dom_sid); + if (!NDR_ERR_CODE_IS_SUCCESS(ndr_err)) { + talloc_free(sid); + return NULL; + } + + return sid; +} + +/** + * Initialize idmap context + * + * talloc_free to close. + * + * \param mem_ctx talloc context to use. + * \return allocated idmap_context on success, NULL on error + */ +struct idmap_context *idmap_init(TALLOC_CTX *mem_ctx, + struct loadparm_context *lp_ctx) +{ + struct idmap_context *idmap_ctx; + + idmap_ctx = talloc(mem_ctx, struct idmap_context); + if (idmap_ctx == NULL) { + return NULL; + } + + idmap_ctx->lp_ctx = lp_ctx; + + idmap_ctx->ldb_ctx = ldb_wrap_connect(mem_ctx, lp_ctx, + lp_idmap_url(lp_ctx), + system_session(mem_ctx, lp_ctx), + NULL, 0, NULL); + if (idmap_ctx->ldb_ctx == NULL) { + return NULL; + } + + return idmap_ctx; +} + +/** + * Convert a uid to the corresponding SID + * + * \param idmap_ctx idmap context to use + * \param mem_ctx talloc context the memory for the struct dom_sid is allocated + * from. + * \param uid Unix uid to map to a SID + * \param sid Pointer that will take the struct dom_sid pointer if the mapping + * succeeds. + * \return NT_STATUS_OK on success, NT_STATUS_NONE_MAPPED if mapping not + * possible or some other NTSTATUS that is more descriptive on failure. + */ + +NTSTATUS idmap_uid_to_sid(struct idmap_context *idmap_ctx, TALLOC_CTX *mem_ctx, + const uid_t uid, struct dom_sid **sid) +{ + int ret; + NTSTATUS status = NT_STATUS_NONE_MAPPED; + struct ldb_context *ldb = idmap_ctx->ldb_ctx; + struct ldb_message *msg; + struct ldb_result *res = NULL; + int trans = -1; + uid_t low, high; + char *sid_string, *uid_string; + struct dom_sid *unix_users_sid, *new_sid; + TALLOC_CTX *tmp_ctx = talloc_new(mem_ctx); + + ret = ldb_search_exp_fmt(ldb, tmp_ctx, &res, NULL, LDB_SCOPE_SUBTREE, + NULL, "(&(objectClass=sidMap)(uidNumber=%u))", + uid); + if (ret != LDB_SUCCESS) { + DEBUG(1, ("Search failed: %s\n", ldb_errstring(ldb))); + status = NT_STATUS_NONE_MAPPED; + goto failed; + } + + if (res->count == 1) { + *sid = idmap_msg_get_dom_sid(mem_ctx, res->msgs[0], + "objectSid"); + if (*sid == NULL) { + DEBUG(1, ("Failed to get sid from db: %u\n", ret)); + status = NT_STATUS_NONE_MAPPED; + goto failed; + } + talloc_free(tmp_ctx); + return NT_STATUS_OK; + } + + DEBUG(6, ("uid not found in idmap db, trying to allocate SID.\n")); + + trans = ldb_transaction_start(ldb); + if (trans != LDB_SUCCESS) { + status = NT_STATUS_NONE_MAPPED; + goto failed; + } + + /* Now redo the search to make sure noone added a mapping for that SID + * while we weren't looking.*/ + ret = ldb_search_exp_fmt(ldb, tmp_ctx, &res, NULL, LDB_SCOPE_SUBTREE, + NULL, "(&(objectClass=sidMap)(uidNumber=%u))", + uid); + if (ret != LDB_SUCCESS) { + DEBUG(1, ("Search failed: %s\n", ldb_errstring(ldb))); + status = NT_STATUS_NONE_MAPPED; + goto failed; + } + + if (res->count > 0) { + DEBUG(1, ("sidMap modified while trying to add a mapping.\n")); + status = NT_STATUS_RETRY; + goto failed; + } + + ret = idmap_get_bounds(idmap_ctx, &low, &high); + if (ret != LDB_SUCCESS) { + DEBUG(1, ("Failed to get id bounds from db: %u\n", ret)); + status = NT_STATUS_NONE_MAPPED; + goto failed; + } + + if (uid >= low && uid <= high) { + /* An existing user would have been mapped before */ + status = NT_STATUS_NO_SUCH_USER; + goto failed; + } + + /* For local users, we just create a rid = uid +1, so root doesn't end + * up with a 0 rid */ + unix_users_sid = dom_sid_parse_talloc(tmp_ctx, "S-1-22-1"); + if (unix_users_sid == NULL) { + status = NT_STATUS_NO_MEMORY; + goto failed; + } + + new_sid = dom_sid_add_rid(mem_ctx, unix_users_sid, uid + 1); + if (new_sid == NULL) { + status = NT_STATUS_NO_MEMORY; + goto failed; + } + + sid_string = dom_sid_string(tmp_ctx, new_sid); + if (sid_string == NULL) { + status = NT_STATUS_NO_MEMORY; + goto failed; + } + + uid_string = talloc_asprintf(tmp_ctx, "%u", uid); + if (uid_string == NULL) { + status = NT_STATUS_NO_MEMORY; + goto failed; + } + + msg = ldb_msg_new(tmp_ctx); + if (msg == NULL) { + status = NT_STATUS_NO_MEMORY; + goto failed; + } + + msg->dn = ldb_dn_new_fmt(tmp_ctx, ldb, "CN=%s", sid_string); + if (msg->dn == NULL) { + status = NT_STATUS_NO_MEMORY; + goto failed; + } + + ret = ldb_msg_add_string(msg, "uidNumber", uid_string); + if (ret != LDB_SUCCESS) { + status = NT_STATUS_NONE_MAPPED; + goto failed; + } + + ret = idmap_msg_add_dom_sid(idmap_ctx, tmp_ctx, msg, "objectSid", + new_sid); + if (ret != LDB_SUCCESS) { + status = NT_STATUS_NONE_MAPPED; + goto failed; + } + + ret = ldb_msg_add_string(msg, "objectClass", "sidMap"); + if (ret != LDB_SUCCESS) { + status = NT_STATUS_NONE_MAPPED; + goto failed; + } + + ret = ldb_msg_add_string(msg, "cn", sid_string); + if (ret != LDB_SUCCESS) { + status = NT_STATUS_NONE_MAPPED; + goto failed; + } + + ret = ldb_add(ldb, msg); + if (ret != LDB_SUCCESS) { + status = NT_STATUS_NONE_MAPPED; + goto failed; + } + + trans = ldb_transaction_commit(ldb); + if (trans != LDB_SUCCESS) { + status = NT_STATUS_NONE_MAPPED; + goto failed; + } + + *sid = new_sid; + talloc_free(tmp_ctx); + return NT_STATUS_OK; + +failed: + if (trans == LDB_SUCCESS) ldb_transaction_cancel(ldb); + talloc_free(tmp_ctx); + return status; +} + +/** + * Map a Unix gid to the corresponding SID + * + * \param idmap_ctx idmap context to use + * \param mem_ctx talloc context the memory for the struct dom_sid is allocated + * from. + * \param gid Unix gid to map to a SID + * \param sid Pointer that will take the struct dom_sid pointer if mapping + * succeeds. + * \return NT_STATUS_OK on success, NT_STATUS_NONE_MAPPED if mapping not + * possible or some other NTSTATUS that is more descriptive on failure. + */ +NTSTATUS idmap_gid_to_sid(struct idmap_context *idmap_ctx, TALLOC_CTX *mem_ctx, + const gid_t gid, struct dom_sid **sid) +{ + int ret; + NTSTATUS status = NT_STATUS_NONE_MAPPED; + struct ldb_context *ldb = idmap_ctx->ldb_ctx; + struct ldb_message *msg; + struct ldb_result *res = NULL; + int trans = -1; + gid_t low, high; + char *sid_string, *gid_string; + struct dom_sid *unix_groups_sid, *new_sid; + TALLOC_CTX *tmp_ctx = talloc_new(mem_ctx); + + ret = ldb_search_exp_fmt(ldb, tmp_ctx, &res, NULL, LDB_SCOPE_SUBTREE, + NULL, "(&(objectClass=sidMap)(gidNumber=%u))", gid); + if (ret != LDB_SUCCESS) { + DEBUG(1, ("Search failed: %s\n", ldb_errstring(ldb))); + status = NT_STATUS_NONE_MAPPED; + goto failed; + } + + if (res->count == 1) { + *sid = idmap_msg_get_dom_sid(mem_ctx, res->msgs[0], + "objectSid"); + if (*sid == NULL) { + DEBUG(1, ("Failed to get sid from db: %u\n", ret)); + status = NT_STATUS_NONE_MAPPED; + goto failed; + } + /* No change, so cancel the transaction */ + ldb_transaction_cancel(ldb); + talloc_free(tmp_ctx); + return NT_STATUS_OK; + } + + DEBUG(6, ("gid not found in idmap db, trying to allocate SID.\n")); + + trans = ldb_transaction_start(ldb); + if (trans != LDB_SUCCESS) { + status = NT_STATUS_NONE_MAPPED; + goto failed; + } + + /* Now redo the search to make sure noone added a mapping for that SID + * while we weren't looking.*/ + ret = ldb_search_exp_fmt(ldb, tmp_ctx, &res, NULL, LDB_SCOPE_SUBTREE, + NULL, "(&(objectClass=sidMap)(gidNumber=%u))", + gid); + if (ret != LDB_SUCCESS) { + DEBUG(1, ("Search failed: %s\n", ldb_errstring(ldb))); + status = NT_STATUS_NONE_MAPPED; + goto failed; + } + + if (res->count > 0) { + DEBUG(1, ("sidMap modified while trying to add a mapping.\n")); + status = NT_STATUS_RETRY; + goto failed; + } + + ret = idmap_get_bounds(idmap_ctx, &low, &high); + if (ret != LDB_SUCCESS) { + DEBUG(1, ("Failed to get id bounds from db: %u\n", ret)); + status = NT_STATUS_NONE_MAPPED; + goto failed; + } + + if (gid >= low && gid <= high) { + /* An existing group would have been mapped before */ + status = NT_STATUS_NO_SUCH_USER; + goto failed; + } + + /* For local groups, we just create a rid = gid +1, so root doesn't end + * up with a 0 rid */ + unix_groups_sid = dom_sid_parse_talloc(tmp_ctx, "S-1-22-2"); + if (unix_groups_sid == NULL) { + status = NT_STATUS_NO_MEMORY; + goto failed; + } + + new_sid = dom_sid_add_rid(mem_ctx, unix_groups_sid, gid + 1); + if (new_sid == NULL) { + status = NT_STATUS_NO_MEMORY; + goto failed; + } + + sid_string = dom_sid_string(tmp_ctx, new_sid); + if (sid_string == NULL) { + status = NT_STATUS_NO_MEMORY; + goto failed; + } + + gid_string = talloc_asprintf(tmp_ctx, "%u", gid); + if (gid_string == NULL) { + status = NT_STATUS_NO_MEMORY; + goto failed; + } + + msg = ldb_msg_new(tmp_ctx); + if (msg == NULL) { + status = NT_STATUS_NO_MEMORY; + goto failed; + } + + msg->dn = ldb_dn_new_fmt(tmp_ctx, ldb, "CN=%s", sid_string); + if (msg->dn == NULL) { + status = NT_STATUS_NO_MEMORY; + goto failed; + } + + ret = ldb_msg_add_string(msg, "gidNumber", gid_string); + if (ret != LDB_SUCCESS) { + status = NT_STATUS_NONE_MAPPED; + goto failed; + } + + ret = idmap_msg_add_dom_sid(idmap_ctx, tmp_ctx, msg, "objectSid", + new_sid); + if (ret != LDB_SUCCESS) { + status = NT_STATUS_NONE_MAPPED; + goto failed; + } + + ret = ldb_msg_add_string(msg, "objectClass", "sidMap"); + if (ret != LDB_SUCCESS) { + status = NT_STATUS_NONE_MAPPED; + goto failed; + } + + ret = ldb_msg_add_string(msg, "cn", sid_string); + if (ret != LDB_SUCCESS) { + status = NT_STATUS_NONE_MAPPED; + goto failed; + } + + ret = ldb_add(ldb, msg); + if (ret != LDB_SUCCESS) { + status = NT_STATUS_NONE_MAPPED; + goto failed; + } + + trans = ldb_transaction_commit(ldb); + if (trans != LDB_SUCCESS) { + status = NT_STATUS_NONE_MAPPED; + goto failed; + } + + *sid = new_sid; + talloc_free(tmp_ctx); + return NT_STATUS_OK; + +failed: + if (trans == LDB_SUCCESS) ldb_transaction_cancel(ldb); + talloc_free(tmp_ctx); + return status; +} + +/** + * Map a SID to a Unix uid. + * + * If no mapping exists, a new mapping will be created. + * + * \todo Check if SIDs can be resolved if lp_idmap_trusted_only() == true + * + * \param idmap_ctx idmap context to use + * \param mem_ctx talloc context to use + * \param sid SID to map to a Unix uid + * \param uid pointer to receive the mapped uid + * \return NT_STATUS_OK on success, NT_STATUS_INVALID_SID if the sid is not from + * a trusted domain and idmap trusted only = true, NT_STATUS_NONE_MAPPED if the + * mapping failed. + */ +NTSTATUS idmap_sid_to_uid(struct idmap_context *idmap_ctx, TALLOC_CTX *mem_ctx, + const struct dom_sid *sid, uid_t *uid) +{ + int ret; + NTSTATUS status = NT_STATUS_NONE_MAPPED; + struct ldb_context *ldb = idmap_ctx->ldb_ctx; + struct ldb_dn *dn; + struct ldb_message *hwm_msg, *map_msg; + struct ldb_result *res = NULL; + int trans; + uid_t low, high, hwm, new_uid; + char *sid_string, *uid_string, *hwm_string; + bool hwm_entry_exists; + TALLOC_CTX *tmp_ctx = talloc_new(mem_ctx); + + ret = ldb_search_exp_fmt(ldb, tmp_ctx, &res, NULL, LDB_SCOPE_SUBTREE, + NULL, "(&(objectClass=sidMap)(objectSid=%s))", + ldap_encode_ndr_dom_sid(tmp_ctx, sid)); + if (ret != LDB_SUCCESS) { + DEBUG(1, ("Search failed: %s\n", ldb_errstring(ldb))); + status = NT_STATUS_NONE_MAPPED; + goto failed; + } + + if (res->count == 1) { + new_uid = ldb_msg_find_attr_as_uint(res->msgs[0], "uidNumber", + -1); + if (new_uid == (uid_t) -1) { + DEBUG(1, ("Invalid uid mapping.\n")); + status = NT_STATUS_NONE_MAPPED; + goto failed; + } + *uid = new_uid; + talloc_free(tmp_ctx); + return NT_STATUS_OK; + } + + DEBUG(6, ("No existing mapping found, attempting to create one.\n")); + + trans = ldb_transaction_start(ldb); + if (trans != LDB_SUCCESS) { + status = NT_STATUS_NONE_MAPPED; + goto failed; + } + + /* Redo the search to make sure noone changed the mapping while we + * weren't looking */ + ret = ldb_search_exp_fmt(ldb, tmp_ctx, &res, NULL, LDB_SCOPE_SUBTREE, + NULL, "(&(objectClass=sidMap)(objectSid=%s))", + ldap_encode_ndr_dom_sid(tmp_ctx, sid)); + if (ret != LDB_SUCCESS) { + DEBUG(1, ("Search failed: %s\n", ldb_errstring(ldb))); + status = NT_STATUS_NONE_MAPPED; + goto failed; + } + + if (res->count > 0) { + DEBUG(1, ("Database changed while trying to add a sidmap.\n")); + status = NT_STATUS_RETRY; + goto failed; + } + + /*FIXME: if lp_idmap_trusted_only() == true, check if SID can be + * resolved here. */ + + ret = idmap_get_bounds(idmap_ctx, &low, &high); + if (ret != LDB_SUCCESS) { + status = NT_STATUS_NONE_MAPPED; + goto failed; + } + + dn = ldb_dn_new(tmp_ctx, ldb, "CN=CONFIG"); + if (dn == NULL) { + status = NT_STATUS_NO_MEMORY; + goto failed; + } + + ret = ldb_search(ldb, dn, LDB_SCOPE_BASE, NULL, NULL, &res); + if (ret != LDB_SUCCESS) { + DEBUG(1, ("Search failed: %s\n", ldb_errstring(ldb))); + status = NT_STATUS_NONE_MAPPED; + goto failed; + } + + talloc_steal(tmp_ctx, res); + + if (res->count != 1) { + DEBUG(1, ("No CN=CONFIG record, idmap database is broken.\n")); + status = NT_STATUS_NONE_MAPPED; + goto failed; + } + + hwm = ldb_msg_find_attr_as_uint(res->msgs[0], "uidNumber", -1); + if (hwm == (uid_t)-1) { + hwm = low; + hwm_entry_exists = false; + } else { + hwm_entry_exists = true; + } + + if (hwm > high) { + DEBUG(1, ("Out of uids to allocate.\n")); + status = NT_STATUS_NONE_MAPPED; + goto failed; + } + + hwm_msg = ldb_msg_new(tmp_ctx); + if (hwm_msg == NULL) { + DEBUG(1, ("Out of memory when creating ldb_message\n")); + status = NT_STATUS_NO_MEMORY; + goto failed; + } + + hwm_msg->dn = dn; + + new_uid = hwm; + hwm++; + + hwm_string = talloc_asprintf(tmp_ctx, "%u", hwm); + if (hwm_string == NULL) { + status = NT_STATUS_NO_MEMORY; + goto failed; + } + + sid_string = dom_sid_string(tmp_ctx, sid); + if (sid_string == NULL) { + status = NT_STATUS_NO_MEMORY; + goto failed; + } + + uid_string = talloc_asprintf(tmp_ctx, "%u", new_uid); + if (uid_string == NULL) { + status = NT_STATUS_NO_MEMORY; + goto failed; + } + + if (hwm_entry_exists) { + struct ldb_message_element *els; + struct ldb_val *vals; + + /* We're modifying the entry, not just adding a new one. */ + els = talloc_array(tmp_ctx, struct ldb_message_element, 2); + if (els == NULL) { + status = NT_STATUS_NO_MEMORY; + goto failed; + } + + vals = talloc_array(tmp_ctx, struct ldb_val, 2); + if (els == NULL) { + status = NT_STATUS_NO_MEMORY; + goto failed; + } + + hwm_msg->num_elements = 2; + hwm_msg->elements = els; + + els[0].num_values = 1; + els[0].values = &vals[0]; + els[0].flags = LDB_FLAG_MOD_DELETE; + els[0].name = talloc_strdup(tmp_ctx, "uidNumber"); + if (els[0].name == NULL) { + status = NT_STATUS_NO_MEMORY; + goto failed; + } + + els[1].num_values = 1; + els[1].values = &vals[1]; + els[1].flags = LDB_FLAG_MOD_ADD; + els[1].name = els[0].name; + + vals[0].data = (uint8_t *)uid_string; + vals[0].length = strlen(uid_string); + vals[1].data = (uint8_t *)hwm_string; + vals[1].length = strlen(hwm_string); + } else { + ret = ldb_msg_add_empty(hwm_msg, "uidNumber", LDB_FLAG_MOD_ADD, + NULL); + if (ret != LDB_SUCCESS) { + status = NT_STATUS_NONE_MAPPED; + goto failed; + } + + ret = ldb_msg_add_string(hwm_msg, "uidNumber", hwm_string); + if (ret != LDB_SUCCESS) + { + status = NT_STATUS_NONE_MAPPED; + goto failed; + } + } + + ret = ldb_modify(ldb, hwm_msg); + if (ret != LDB_SUCCESS) { + DEBUG(1, ("Updating the uid high water mark failed: %s\n", + ldb_errstring(ldb))); + status = NT_STATUS_NONE_MAPPED; + goto failed; + } + + map_msg = ldb_msg_new(tmp_ctx); + if (map_msg == NULL) { + status = NT_STATUS_NO_MEMORY; + goto failed; + } + + map_msg->dn = ldb_dn_new_fmt(tmp_ctx, ldb, "CN=%s", sid_string); + if (map_msg->dn == NULL) { + status = NT_STATUS_NO_MEMORY; + goto failed; + } + + ret = ldb_msg_add_string(map_msg, "uidNumber", uid_string); + if (ret != LDB_SUCCESS) { + status = NT_STATUS_NONE_MAPPED; + goto failed; + } + + ret = idmap_msg_add_dom_sid(idmap_ctx, tmp_ctx, map_msg, "objectSid", + sid); + if (ret != LDB_SUCCESS) { + status = NT_STATUS_NONE_MAPPED; + goto failed; + } + + ret = ldb_msg_add_string(map_msg, "objectClass", "sidMap"); + if (ret != LDB_SUCCESS) { + status = NT_STATUS_NONE_MAPPED; + goto failed; + } + + ret = ldb_msg_add_string(map_msg, "cn", sid_string); + if (ret != LDB_SUCCESS) { + status = NT_STATUS_NONE_MAPPED; + goto failed; + } + + ret = ldb_add(ldb, map_msg); + if (ret != LDB_SUCCESS) { + DEBUG(1, ("Adding a sidmap failed: %s\n", ldb_errstring(ldb))); + status = NT_STATUS_NONE_MAPPED; + goto failed; + } + + trans = ldb_transaction_commit(ldb); + if (trans != LDB_SUCCESS) { + DEBUG(1, ("Transaction failed: %s\n", ldb_errstring(ldb))); + status = NT_STATUS_NONE_MAPPED; + goto failed; + } + + *uid = new_uid; + talloc_free(tmp_ctx); + return NT_STATUS_OK; + +failed: + if (trans == LDB_SUCCESS) ldb_transaction_cancel(ldb); + talloc_free(tmp_ctx); + return status; +} + +/** + * Map a SID to a Unix gid. + * + * If no mapping exist, a new mapping will be created. + * + * \todo Check if SID resolve when lp_idmap_trusted_only() == true + * + * \param idmap_ctx idmap context to use + * \param mem_ctx talloc context to use + * \param sid SID to map to a Unix gid + * \param gid pointer to receive the mapped gid + * \return NT_STATUS_OK on success, NT_STATUS_INVALID_SID if the sid is not from + * a trusted domain and idmap trusted only = true, NT_STATUS_NONE_MAPPED if the + * mapping failed. + */ +NTSTATUS idmap_sid_to_gid(struct idmap_context *idmap_ctx, TALLOC_CTX *mem_ctx, + const struct dom_sid *sid, gid_t *gid) +{ + int ret; + NTSTATUS status = NT_STATUS_NONE_MAPPED; + struct ldb_context *ldb = idmap_ctx->ldb_ctx; + struct ldb_dn *dn; + struct ldb_message *hwm_msg, *map_msg; + struct ldb_result *res = NULL; + int trans = -1; + gid_t low, high, hwm, new_gid; + char *sid_string, *gid_string, *hwm_string; + bool hwm_entry_exists; + TALLOC_CTX *tmp_ctx = talloc_new(mem_ctx); + + ret = ldb_search_exp_fmt(ldb, tmp_ctx, &res, NULL, LDB_SCOPE_SUBTREE, + NULL, "(&(objectClass=sidMap)(objectSid=%s))", + ldap_encode_ndr_dom_sid(tmp_ctx, sid)); + if (ret != LDB_SUCCESS) { + DEBUG(1, ("Search failed: %s\n", ldb_errstring(ldb))); + status = NT_STATUS_NONE_MAPPED; + goto failed; + } + + if (res->count == 1) { + new_gid = ldb_msg_find_attr_as_uint(res->msgs[0], "gidNumber", + -1); + if (new_gid == (gid_t) -1) { + DEBUG(1, ("Invalid gid mapping.\n")); + status = NT_STATUS_NONE_MAPPED; + goto failed; + } + *gid = new_gid; + talloc_free(tmp_ctx); + return NT_STATUS_OK; + } + + DEBUG(6, ("No existing mapping found, attempting to create one.\n")); + + trans = ldb_transaction_start(ldb); + if (trans != LDB_SUCCESS) { + status = NT_STATUS_NONE_MAPPED; + goto failed; + } + + /* Redo the search to make sure noone changed the mapping while we + * weren't looking */ + ret = ldb_search_exp_fmt(ldb, tmp_ctx, &res, NULL, LDB_SCOPE_SUBTREE, + NULL, "(&(objectClass=sidMap)(objectSid=%s))", + ldap_encode_ndr_dom_sid(tmp_ctx, sid)); + if (ret != LDB_SUCCESS) { + DEBUG(1, ("Search failed: %s\n", ldb_errstring(ldb))); + status = NT_STATUS_NONE_MAPPED; + goto failed; + } + + if (res->count > 0) { + DEBUG(1, ("Database changed while trying to add a sidmap.\n")); + status = NT_STATUS_RETRY; + goto failed; + } + + /*FIXME: if lp_idmap_trusted_only() == true, check if SID can be + * resolved here. */ + + ret = idmap_get_bounds(idmap_ctx, &low, &high); + if (ret != LDB_SUCCESS) { + status = NT_STATUS_NONE_MAPPED; + goto failed; + } + + dn = ldb_dn_new(tmp_ctx, ldb, "CN=CONFIG"); + if (dn == NULL) { + status = NT_STATUS_NO_MEMORY; + goto failed; + } + + ret = ldb_search(ldb, dn, LDB_SCOPE_BASE, NULL, NULL, &res); + if (ret != LDB_SUCCESS) { + DEBUG(1, ("Search failed: %s\n", ldb_errstring(ldb))); + status = NT_STATUS_NONE_MAPPED; + goto failed; + } + + talloc_steal(tmp_ctx, res); + + if (res->count != 1) { + DEBUG(1, ("No CN=CONFIG record, idmap database is broken.\n")); + status = NT_STATUS_NONE_MAPPED; + goto failed; + } + + hwm = ldb_msg_find_attr_as_uint(res->msgs[0], "gidNumber", -1); + if (hwm == (gid_t)-1) { + hwm = low; + hwm_entry_exists = false; + } else { + hwm_entry_exists = true; + } + + if (hwm > high) { + DEBUG(1, ("Out of gids to allocate.\n")); + status = NT_STATUS_NONE_MAPPED; + goto failed; + } + + hwm_msg = ldb_msg_new(tmp_ctx); + if (hwm_msg == NULL) { + DEBUG(1, ("Out of memory when creating ldb_message\n")); + status = NT_STATUS_NO_MEMORY; + goto failed; + } + + hwm_msg->dn = dn; + + new_gid = hwm; + hwm++; + + hwm_string = talloc_asprintf(tmp_ctx, "%u", hwm); + if (hwm_string == NULL) { + status = NT_STATUS_NO_MEMORY; + goto failed; + } + + sid_string = dom_sid_string(tmp_ctx, sid); + if (sid_string == NULL) { + status = NT_STATUS_NO_MEMORY; + goto failed; + } + + gid_string = talloc_asprintf(tmp_ctx, "%u", new_gid); + if (gid_string == NULL) { + status = NT_STATUS_NO_MEMORY; + goto failed; + } + + if (hwm_entry_exists) { + struct ldb_message_element *els; + struct ldb_val *vals; + + /* We're modifying the entry, not just adding a new one. */ + els = talloc_array(tmp_ctx, struct ldb_message_element, 2); + if (els == NULL) { + status = NT_STATUS_NO_MEMORY; + goto failed; + } + + vals = talloc_array(tmp_ctx, struct ldb_val, 2); + if (els == NULL) { + status = NT_STATUS_NO_MEMORY; + goto failed; + } + + hwm_msg->num_elements = 2; + hwm_msg->elements = els; + + els[0].num_values = 1; + els[0].values = &vals[0]; + els[0].flags = LDB_FLAG_MOD_DELETE; + els[0].name = talloc_strdup(tmp_ctx, "gidNumber"); + if (els[0].name == NULL) { + status = NT_STATUS_NO_MEMORY; + goto failed; + } + + els[1].num_values = 1; + els[1].values = &vals[1]; + els[1].flags = LDB_FLAG_MOD_ADD; + els[1].name = els[0].name; + + vals[0].data = (uint8_t *)gid_string; + vals[0].length = strlen(gid_string); + vals[1].data = (uint8_t *)hwm_string; + vals[1].length = strlen(hwm_string); + } else { + ret = ldb_msg_add_empty(hwm_msg, "gidNumber", LDB_FLAG_MOD_ADD, + NULL); + if (ret != LDB_SUCCESS) { + status = NT_STATUS_NONE_MAPPED; + goto failed; + } + + ret = ldb_msg_add_string(hwm_msg, "gidNumber", hwm_string); + if (ret != LDB_SUCCESS) + { + status = NT_STATUS_NONE_MAPPED; + goto failed; + } + } + + ret = ldb_modify(ldb, hwm_msg); + if (ret != LDB_SUCCESS) { + DEBUG(1, ("Updating the gid high water mark failed: %s\n", + ldb_errstring(ldb))); + status = NT_STATUS_NONE_MAPPED; + goto failed; + } + + map_msg = ldb_msg_new(tmp_ctx); + if (map_msg == NULL) { + status = NT_STATUS_NO_MEMORY; + goto failed; + } + + map_msg->dn = ldb_dn_new_fmt(tmp_ctx, ldb, "CN=%s", sid_string); + if (map_msg->dn == NULL) { + status = NT_STATUS_NO_MEMORY; + goto failed; + } + + ret = ldb_msg_add_string(map_msg, "gidNumber", gid_string); + if (ret != LDB_SUCCESS) { + status = NT_STATUS_NONE_MAPPED; + goto failed; + } + + ret = idmap_msg_add_dom_sid(idmap_ctx, tmp_ctx, map_msg, "objectSid", + sid); + if (ret != LDB_SUCCESS) { + status = NT_STATUS_NONE_MAPPED; + goto failed; + } + + ret = ldb_msg_add_string(map_msg, "objectClass", "sidMap"); + if (ret != LDB_SUCCESS) { + status = NT_STATUS_NONE_MAPPED; + goto failed; + } + + ret = ldb_msg_add_string(map_msg, "cn", sid_string); + if (ret != LDB_SUCCESS) { + status = NT_STATUS_NONE_MAPPED; + goto failed; + } + + ret = ldb_add(ldb, map_msg); + if (ret != LDB_SUCCESS) { + DEBUG(1, ("Adding a sidmap failed: %s\n", ldb_errstring(ldb))); + status = NT_STATUS_NONE_MAPPED; + goto failed; + } + + trans = ldb_transaction_commit(ldb); + if (trans != LDB_SUCCESS) { + DEBUG(1, ("Transaction failed: %s\n", ldb_errstring(ldb))); + status = NT_STATUS_NONE_MAPPED; + goto failed; + } + + *gid = new_gid; + talloc_free(tmp_ctx); + return NT_STATUS_OK; + +failed: + if (trans == LDB_SUCCESS) ldb_transaction_cancel(ldb); + talloc_free(tmp_ctx); + return status; +} + |