diff options
Diffstat (limited to 'source4/winbind/idmap.c')
| -rw-r--r-- | source4/winbind/idmap.c | 718 |
1 files changed, 718 insertions, 0 deletions
diff --git a/source4/winbind/idmap.c b/source4/winbind/idmap.c new file mode 100644 index 0000000000..333a86445a --- /dev/null +++ b/source4/winbind/idmap.c @@ -0,0 +1,718 @@ +/* + Unix SMB/CIFS implementation. + + Map SIDs to unixids 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 event_context *ev_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, ev_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; + } + + idmap_ctx->unix_groups_sid = dom_sid_parse_talloc(mem_ctx, "S-1-22-2"); + if (idmap_ctx->unix_groups_sid == NULL) { + return NULL; + } + + idmap_ctx->unix_users_sid = dom_sid_parse_talloc(mem_ctx, "S-1-22-1"); + if (idmap_ctx->unix_users_sid == NULL) { + return NULL; + } + + return idmap_ctx; +} + +/** + * Convert an unixid 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 unixid pointer to a unixid struct to convert + * \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_xid_to_sid(struct idmap_context *idmap_ctx, TALLOC_CTX *mem_ctx, + const struct unixid *unixid, struct dom_sid **sid) +{ + int ret; + NTSTATUS status = NT_STATUS_NONE_MAPPED; + struct ldb_context *ldb = idmap_ctx->ldb_ctx; + struct ldb_result *res = NULL; + struct dom_sid *unix_sid, *new_sid; + TALLOC_CTX *tmp_ctx = talloc_new(mem_ctx); + const char *id_type; + + switch (unixid->type) { + case ID_TYPE_UID: + id_type = "ID_TYPE_UID"; + break; + case ID_TYPE_GID: + id_type = "ID_TYPE_GID"; + break; + default: + DEBUG(1, ("unixid->type must be type gid or uid\n")); + status = NT_STATUS_NONE_MAPPED; + goto failed; + } + + ret = ldb_search_exp_fmt(ldb, tmp_ctx, &res, NULL, LDB_SCOPE_SUBTREE, + NULL, "(&(|(type=ID_TYPE_BOTH)(type=%s))" + "(xidNumber=%u))", id_type, unixid->id); + 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, ("xid not found in idmap db, create S-1-22- SID.\n")); + + /* For local users/groups , we just create a rid = uid/gid */ + if (unixid->type == ID_TYPE_UID) { + unix_sid = dom_sid_parse_talloc(tmp_ctx, "S-1-22-1"); + } else { + unix_sid = dom_sid_parse_talloc(tmp_ctx, "S-1-22-2"); + } + if (unix_sid == NULL) { + status = NT_STATUS_NO_MEMORY; + goto failed; + } + + new_sid = dom_sid_add_rid(mem_ctx, unix_sid, unixid->id); + if (new_sid == NULL) { + status = NT_STATUS_NO_MEMORY; + goto failed; + } + + *sid = new_sid; + talloc_free(tmp_ctx); + return NT_STATUS_OK; + +failed: + talloc_free(tmp_ctx); + return status; +} + + +/** + * Map a SID to an unixid struct. + * + * If no mapping exists, a new mapping will be created. + * + * \todo Check if SIDs can be resolved if lp_idmap_trusted_only() == true + * \todo Fix backwards compatibility for Samba3 + * + * \param idmap_ctx idmap context to use + * \param mem_ctx talloc context to use + * \param sid SID to map to an unixid struct + * \param unixid pointer to a unixid struct pointer + * \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_xid(struct idmap_context *idmap_ctx, TALLOC_CTX *mem_ctx, + const struct dom_sid *sid, struct unixid **unixid) +{ + 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; + uint32_t low, high, hwm, new_xid; + char *sid_string, *unixid_string, *hwm_string; + bool hwm_entry_exists; + TALLOC_CTX *tmp_ctx = talloc_new(mem_ctx); + + if (dom_sid_in_domain(idmap_ctx->unix_users_sid, sid)) { + uint32_t rid; + DEBUG(6, ("This is a local unix uid, just calculate that.\n")); + status = dom_sid_split_rid(tmp_ctx, sid, NULL, &rid); + if (!NT_STATUS_IS_OK(status)) goto failed; + + *unixid = talloc(mem_ctx, struct unixid); + if (*unixid == NULL) { + status = NT_STATUS_NO_MEMORY; + goto failed; + } + (*unixid)->id = rid; + (*unixid)->type = ID_TYPE_UID; + + talloc_free(tmp_ctx); + return NT_STATUS_OK; + } + + if (dom_sid_in_domain(idmap_ctx->unix_groups_sid, sid)) { + uint32_t rid; + DEBUG(6, ("This is a local unix gid, just calculate that.\n")); + status = dom_sid_split_rid(tmp_ctx, sid, NULL, &rid); + if (!NT_STATUS_IS_OK(status)) goto failed; + + *unixid = talloc(mem_ctx, struct unixid); + if (*unixid == NULL) { + status = NT_STATUS_NO_MEMORY; + goto failed; + } + (*unixid)->id = rid; + (*unixid)->type = ID_TYPE_GID; + + talloc_free(tmp_ctx); + return NT_STATUS_OK; + } + + 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) { + const char *type = ldb_msg_find_attr_as_string(res->msgs[0], + "type", NULL); + new_xid = ldb_msg_find_attr_as_uint(res->msgs[0], "xidNumber", + -1); + if (new_xid == (uint32_t) -1) { + DEBUG(1, ("Invalid xid mapping.\n")); + status = NT_STATUS_NONE_MAPPED; + goto failed; + } + + if (type == NULL) { + DEBUG(1, ("Invalid type for mapping entry.\n")); + status = NT_STATUS_NONE_MAPPED; + goto failed; + } + + *unixid = talloc(mem_ctx, struct unixid); + if (*unixid == NULL) { + status = NT_STATUS_NO_MEMORY; + goto failed; + } + + (*unixid)->id = new_xid; + + if (strcmp(type, "ID_TYPE_BOTH") == 0) { + (*unixid)->type = ID_TYPE_BOTH; + } else if (strcmp(type, "ID_TYPE_UID") == 0) { + (*unixid)->type = ID_TYPE_UID; + } else { + (*unixid)->type = ID_TYPE_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], "xidNumber", -1); + if (hwm == (uint32_t)-1) { + hwm = low; + hwm_entry_exists = false; + } else { + hwm_entry_exists = true; + } + + if (hwm > high) { + DEBUG(1, ("Out of xids 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_xid = 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; + } + + unixid_string = talloc_asprintf(tmp_ctx, "%u", new_xid); + if (unixid_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, "xidNumber"); + 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 *)unixid_string; + vals[0].length = strlen(unixid_string); + vals[1].data = (uint8_t *)hwm_string; + vals[1].length = strlen(hwm_string); + } else { + ret = ldb_msg_add_empty(hwm_msg, "xidNumber", LDB_FLAG_MOD_ADD, + NULL); + if (ret != LDB_SUCCESS) { + status = NT_STATUS_NONE_MAPPED; + goto failed; + } + + ret = ldb_msg_add_string(hwm_msg, "xidNumber", 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 xid 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, "xidNumber", unixid_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, "type", "ID_TYPE_BOTH"); + 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; + } + + *unixid = talloc(mem_ctx, struct unixid); + if (*unixid == NULL) { + status = NT_STATUS_NO_MEMORY; + goto failed; + } + + (*unixid)->id = new_xid; + (*unixid)->type = ID_TYPE_BOTH; + talloc_free(tmp_ctx); + return NT_STATUS_OK; + +failed: + if (trans == LDB_SUCCESS) ldb_transaction_cancel(ldb); + talloc_free(tmp_ctx); + return status; +} + +/** + * Convert an array of unixids to the corresponding array of SIDs + * + * \param idmap_ctx idmap context to use + * \param mem_ctx talloc context the memory for the dom_sids is allocated + * from. + * \param count length of id_mapping array. + * \param id array of id_mappings. + * \return NT_STATUS_OK on success, NT_STATUS_NONE_MAPPED if mapping is not + * possible at all, NT_STATUS_SOME_UNMAPPED if some mappings worked and some + * did not. + */ + +NTSTATUS idmap_xids_to_sids(struct idmap_context *idmap_ctx, + TALLOC_CTX *mem_ctx, int count, + struct id_mapping *id) +{ + int i; + int error_count = 0; + + for (i = 0; i < count; ++i) { + id[i].status = idmap_xid_to_sid(idmap_ctx, mem_ctx, + id[i].unixid, &id[i].sid); + if (NT_STATUS_EQUAL(id[i].status, NT_STATUS_RETRY)) { + id[i].status = idmap_xid_to_sid(idmap_ctx, mem_ctx, + id[i].unixid, + &id[i].sid); + } + if (!NT_STATUS_IS_OK(id[i].status)) { + DEBUG(1, ("idmapping xid_to_sid failed for id[%d]\n", i)); + error_count++; + } + } + + if (error_count == count) { + /* Mapping did not work at all. */ + return NT_STATUS_NONE_MAPPED; + } else if (error_count > 0) { + /* Some mappings worked, some did not. */ + return STATUS_SOME_UNMAPPED; + } else { + return NT_STATUS_OK; + } +} + +/** + * Convert an array of SIDs to the corresponding array of unixids + * + * \param idmap_ctx idmap context to use + * \param mem_ctx talloc context the memory for the unixids is allocated + * from. + * \param count length of id_mapping array. + * \param id array of id_mappings. + * \return NT_STATUS_OK on success, NT_STATUS_NONE_MAPPED if mapping is not + * possible at all, NT_STATUS_SOME_UNMAPPED if some mappings worked and some + * did not. + */ + +NTSTATUS idmap_sids_to_xids(struct idmap_context *idmap_ctx, + TALLOC_CTX *mem_ctx, int count, + struct id_mapping *id) +{ + int i; + int error_count = 0; + + for (i = 0; i < count; ++i) { + id[i].status = idmap_sid_to_xid(idmap_ctx, mem_ctx, + id[i].sid, &id[i].unixid); + if (NT_STATUS_EQUAL(id[i].status, NT_STATUS_RETRY)) { + id[i].status = idmap_sid_to_xid(idmap_ctx, mem_ctx, + id[i].sid, + &id[i].unixid); + } + if (!NT_STATUS_IS_OK(id[i].status)) { + DEBUG(1, ("idmapping sid_to_xid failed for id[%d]\n", i)); + error_count++; + } + } + + if (error_count == count) { + /* Mapping did not work at all. */ + return NT_STATUS_NONE_MAPPED; + } else if (error_count > 0) { + /* Some mappings worked, some did not. */ + return STATUS_SOME_UNMAPPED; + } else { + return NT_STATUS_OK; + } +} + |