diff options
Diffstat (limited to 'libcli')
| -rw-r--r-- | libcli/auth/config.mk | 7 | ||||
| -rw-r--r-- | libcli/auth/schannel_state.c | 315 |
2 files changed, 322 insertions, 0 deletions
diff --git a/libcli/auth/config.mk b/libcli/auth/config.mk index 5428f04433..103402099d 100644 --- a/libcli/auth/config.mk +++ b/libcli/auth/config.mk @@ -22,3 +22,10 @@ LIBCLI_AUTH_OBJ_FILES = $(addprefix $(libclicommonsrcdir)/auth/, \ PUBLIC_HEADERS += ../libcli/auth/credentials.h $(eval $(call proto_header_template,$(libclicommonsrcdir)/auth/proto.h,$(LIBCLI_AUTH_OBJ_FILES:.o=.c))) + +[SUBSYSTEM::COMMON_SCHANNELDB] +PRIVATE_DEPENDENCIES = LDB_WRAP + +COMMON_SCHANNELDB_OBJ_FILES = $(addprefix $(libclicommonsrcdir)/auth/, schannel_state.o) +$(eval $(call proto_header_template,$(libclicommonsrcdir)/auth/schannel_state_proto.h,$(COMMON_SCHANNELDB_OBJ_FILES:.o=.c))) + diff --git a/libcli/auth/schannel_state.c b/libcli/auth/schannel_state.c new file mode 100644 index 0000000000..c3f087d7dc --- /dev/null +++ b/libcli/auth/schannel_state.c @@ -0,0 +1,315 @@ +/* + Unix SMB/CIFS implementation. + + module to store/fetch session keys for the schannel server + + Copyright (C) Andrew Tridgell 2004 + Copyright (C) Andrew Bartlett <abartlet@samba.org> 2006-2009 + + 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 "lib/ldb/include/ldb.h" +#include "librpc/gen_ndr/ndr_security.h" +#include "ldb_wrap.h" +#include "../lib/util/util_ldb.h" +#include "libcli/auth/libcli_auth.h" +#include "auth/auth.h" +#include "param/param.h" +#include "auth/gensec/schannel_state.h" + +static struct ldb_val *schannel_dom_sid_ldb_val(TALLOC_CTX *mem_ctx, + struct dom_sid *sid) +{ + enum ndr_err_code ndr_err; + struct ldb_val *v; + + v = talloc(mem_ctx, struct ldb_val); + if (!v) return NULL; + + ndr_err = ndr_push_struct_blob(v, mem_ctx, NULL, sid, + (ndr_push_flags_fn_t)ndr_push_dom_sid); + if (!NDR_ERR_CODE_IS_SUCCESS(ndr_err)) { + talloc_free(v); + return NULL; + } + + return v; +} + +static struct dom_sid *schannel_ldb_val_dom_sid(TALLOC_CTX *mem_ctx, + const struct ldb_val *v) +{ + enum ndr_err_code ndr_err; + struct dom_sid *sid; + + sid = talloc(mem_ctx, struct dom_sid); + if (!sid) return NULL; + + ndr_err = ndr_pull_struct_blob(v, 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; +} + + +/* + remember an established session key for a netr server authentication + use a simple ldb structure +*/ +NTSTATUS schannel_store_session_key(struct ldb_context *ldb, + TALLOC_CTX *mem_ctx, + struct netlogon_creds_CredentialState *creds) +{ + struct ldb_message *msg; + struct ldb_val val, seed, client_state, server_state; + struct ldb_val *sid_val; + char *f; + char *sct; + int ret; + + f = talloc_asprintf(mem_ctx, "%u", (unsigned int)creds->negotiate_flags); + + if (f == NULL) { + return NT_STATUS_NO_MEMORY; + } + + sct = talloc_asprintf(mem_ctx, "%u", (unsigned int)creds->secure_channel_type); + + if (sct == NULL) { + return NT_STATUS_NO_MEMORY; + } + + msg = ldb_msg_new(ldb); + if (msg == NULL) { + return NT_STATUS_NO_MEMORY; + } + + msg->dn = ldb_dn_new_fmt(msg, ldb, "computerName=%s", creds->computer_name); + if ( ! msg->dn) { + return NT_STATUS_NO_MEMORY; + } + + sid_val = schannel_dom_sid_ldb_val(msg, creds->sid); + if (sid_val == NULL) { + return NT_STATUS_NO_MEMORY; + } + + val.data = creds->session_key; + val.length = sizeof(creds->session_key); + + seed.data = creds->seed.data; + seed.length = sizeof(creds->seed.data); + + client_state.data = creds->client.data; + client_state.length = sizeof(creds->client.data); + server_state.data = creds->server.data; + server_state.length = sizeof(creds->server.data); + + ldb_msg_add_string(msg, "objectClass", "schannelState"); + ldb_msg_add_value(msg, "sessionKey", &val, NULL); + ldb_msg_add_value(msg, "seed", &seed, NULL); + ldb_msg_add_value(msg, "clientState", &client_state, NULL); + ldb_msg_add_value(msg, "serverState", &server_state, NULL); + ldb_msg_add_string(msg, "negotiateFlags", f); + ldb_msg_add_string(msg, "secureChannelType", sct); + ldb_msg_add_string(msg, "accountName", creds->account_name); + ldb_msg_add_string(msg, "computerName", creds->computer_name); + ldb_msg_add_value(msg, "objectSid", sid_val, NULL); + + ret = ldb_add(ldb, msg); + if (ret == LDB_ERR_ENTRY_ALREADY_EXISTS) { + int i; + /* from samdb_replace() */ + /* mark all the message elements as LDB_FLAG_MOD_REPLACE */ + for (i=0;i<msg->num_elements;i++) { + msg->elements[i].flags = LDB_FLAG_MOD_REPLACE; + } + + ret = ldb_modify(ldb, msg); + } + + /* We don't need a transaction here, as we either add or + * modify records, never delete them, so it must exist */ + + if (ret != 0) { + DEBUG(0,("Unable to add %s to session key db - %s\n", + ldb_dn_get_linearized(msg->dn), ldb_errstring(ldb))); + return NT_STATUS_INTERNAL_DB_CORRUPTION; + } + + return NT_STATUS_OK; +} + +/* + read back a credentials back for a computer +*/ +NTSTATUS schannel_fetch_session_key(struct ldb_context *ldb, + TALLOC_CTX *mem_ctx, + const char *computer_name, + struct netlogon_creds_CredentialState **creds) +{ + struct ldb_result *res; + int ret; + const struct ldb_val *val; + + *creds = talloc_zero(mem_ctx, struct netlogon_creds_CredentialState); + if (!*creds) { + return NT_STATUS_NO_MEMORY; + } + + ret = ldb_search(ldb, mem_ctx, &res, + NULL, LDB_SCOPE_SUBTREE, NULL, + "(computerName=%s)", computer_name); + if (ret != LDB_SUCCESS) { + DEBUG(3,("schannel: Failed to find a record for client %s: %s\n", computer_name, ldb_errstring(ldb))); + return NT_STATUS_INVALID_HANDLE; + } + if (res->count != 1) { + DEBUG(3,("schannel: Failed to find a record for client: %s (found %d records)\n", computer_name, res->count)); + talloc_free(res); + return NT_STATUS_INVALID_HANDLE; + } + + val = ldb_msg_find_ldb_val(res->msgs[0], "sessionKey"); + if (val == NULL || val->length != 16) { + DEBUG(1,("schannel: record in schannel DB must contain a sessionKey of length 16, when searching for client: %s\n", computer_name)); + talloc_free(res); + return NT_STATUS_INTERNAL_ERROR; + } + + memcpy((*creds)->session_key, val->data, 16); + + val = ldb_msg_find_ldb_val(res->msgs[0], "seed"); + if (val == NULL || val->length != 8) { + DEBUG(1,("schannel: record in schannel DB must contain a vaid seed of length 8, when searching for client: %s\n", computer_name)); + talloc_free(res); + return NT_STATUS_INTERNAL_ERROR; + } + + memcpy((*creds)->seed.data, val->data, 8); + + val = ldb_msg_find_ldb_val(res->msgs[0], "clientState"); + if (val == NULL || val->length != 8) { + DEBUG(1,("schannel: record in schannel DB must contain a vaid clientState of length 8, when searching for client: %s\n", computer_name)); + talloc_free(res); + return NT_STATUS_INTERNAL_ERROR; + } + memcpy((*creds)->client.data, val->data, 8); + + val = ldb_msg_find_ldb_val(res->msgs[0], "serverState"); + if (val == NULL || val->length != 8) { + DEBUG(1,("schannel: record in schannel DB must contain a vaid serverState of length 8, when searching for client: %s\n", computer_name)); + talloc_free(res); + return NT_STATUS_INTERNAL_ERROR; + } + memcpy((*creds)->server.data, val->data, 8); + + (*creds)->negotiate_flags = ldb_msg_find_attr_as_int(res->msgs[0], "negotiateFlags", 0); + + (*creds)->secure_channel_type = ldb_msg_find_attr_as_int(res->msgs[0], "secureChannelType", 0); + + (*creds)->account_name = talloc_strdup(*creds, ldb_msg_find_attr_as_string(res->msgs[0], "accountName", NULL)); + if ((*creds)->account_name == NULL) { + talloc_free(res); + return NT_STATUS_NO_MEMORY; + } + + (*creds)->computer_name = talloc_strdup(*creds, ldb_msg_find_attr_as_string(res->msgs[0], "computerName", NULL)); + if ((*creds)->computer_name == NULL) { + talloc_free(res); + return NT_STATUS_NO_MEMORY; + } + + val = ldb_msg_find_ldb_val(res->msgs[0], "objectSid"); + if (val) { + (*creds)->sid = schannel_ldb_val_dom_sid(*creds, val); + if ((*creds)->sid == NULL) { + talloc_free(res); + return NT_STATUS_INTERNAL_ERROR; + } + } else { + (*creds)->sid = NULL; + } + + talloc_free(res); + return NT_STATUS_OK; +} + +/* + Validate an incoming authenticator against the credentials for the remote machine. + + The credentials are (re)read and from the schannel database, and + written back after the caclulations are performed. + + The creds_out parameter (if not NULL) returns the credentials, if + the caller needs some of that information. + +*/ +NTSTATUS schannel_creds_server_step_check(struct ldb_context *ldb, + TALLOC_CTX *mem_ctx, + bool schannel_in_use, + const char *computer_name, + struct netr_Authenticator *received_authenticator, + struct netr_Authenticator *return_authenticator, + struct netlogon_creds_CredentialState **creds_out) +{ + struct netlogon_creds_CredentialState *creds; + NTSTATUS nt_status; + int ret; + + ret = ldb_transaction_start(ldb); + if (ret != 0) { + return NT_STATUS_INTERNAL_DB_CORRUPTION; + } + + /* Because this is a shared structure (even across + * disconnects) we must update the database every time we + * update the structure */ + + nt_status = schannel_fetch_session_key(ldb, ldb, computer_name, + &creds); + + /* Ensure that once the client and server agree on schannel, that all future calls must use it */ + if (creds->negotiate_flags & NETLOGON_NEG_SCHANNEL && !schannel_in_use) { + DEBUG(0,("schannel_creds_server_step_check: client %s not using schannel for netlogon, despite negotiating it\n", + creds->computer_name )); + return NT_STATUS_ACCESS_DENIED; + } + + if (NT_STATUS_IS_OK(nt_status)) { + nt_status = netlogon_creds_server_step_check(creds, + received_authenticator, + return_authenticator); + } + + if (NT_STATUS_IS_OK(nt_status)) { + nt_status = schannel_store_session_key(ldb, mem_ctx, creds); + } + + if (NT_STATUS_IS_OK(nt_status)) { + ldb_transaction_commit(ldb); + if (creds_out) { + *creds_out = creds; + talloc_steal(mem_ctx, creds); + } + } else { + ldb_transaction_cancel(ldb); + } + return nt_status; +} |