server side dcerpc authentication code
Copyright (C) Andrew Tridgell 2003
-
+ Copyright (C) Stefan (metze) Metzmacher 2004
+
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 2 of the License, or
+ 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,
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, write to the Free Software
- Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
+ along with this program. If not, see <http://www.gnu.org/licenses/>.
*/
#include "includes.h"
-
+#include "rpc_server/dcerpc_server.h"
+#include "librpc/gen_ndr/ndr_dcerpc.h"
+#include "auth/credentials/credentials.h"
+#include "auth/gensec/gensec.h"
/*
parse any auth information from a dcerpc bind request
+ return False if we can't handle the auth request for some
+ reason (in which case we send a bind_nak)
*/
BOOL dcesrv_auth_bind(struct dcesrv_call_state *call)
{
- struct dcerpc_packet *pkt = &call->pkt;
+ struct cli_credentials *server_credentials;
+ struct ncacn_packet *pkt = &call->pkt;
+ struct dcesrv_connection *dce_conn = call->conn;
+ struct dcesrv_auth *auth = &dce_conn->auth_state;
+ NTSTATUS status;
+
+ if (pkt->u.bind.auth_info.length == 0) {
+ dce_conn->auth_state.auth_info = NULL;
+ return True;
+ }
+
+ dce_conn->auth_state.auth_info = talloc(dce_conn, struct dcerpc_auth);
+ if (!dce_conn->auth_state.auth_info) {
+ return False;
+ }
+
+ status = ndr_pull_struct_blob(&pkt->u.bind.auth_info,
+ call,
+ dce_conn->auth_state.auth_info,
+ (ndr_pull_flags_fn_t)ndr_pull_dcerpc_auth);
+ if (!NT_STATUS_IS_OK(status)) {
+ return False;
+ }
+
+ status = gensec_server_start(dce_conn, call->event_ctx, call->msg_ctx, &auth->gensec_security);
+ if (!NT_STATUS_IS_OK(status)) {
+ DEBUG(1, ("Failed to start GENSEC for DCERPC server: %s\n", nt_errstr(status)));
+ return False;
+ }
+
+ server_credentials
+ = cli_credentials_init(call);
+ if (!server_credentials) {
+ DEBUG(1, ("Failed to init server credentials\n"));
+ return False;
+ }
+
+ cli_credentials_set_conf(server_credentials);
+ status = cli_credentials_set_machine_account(server_credentials);
+ if (!NT_STATUS_IS_OK(status)) {
+ DEBUG(10, ("Failed to obtain server credentials, perhaps a standalone server?: %s\n", nt_errstr(status)));
+ talloc_free(server_credentials);
+ server_credentials = NULL;
+ }
+
+ gensec_set_credentials(auth->gensec_security, server_credentials);
+
+ status = gensec_start_mech_by_authtype(auth->gensec_security, auth->auth_info->auth_type,
+ auth->auth_info->auth_level);
+
+ if (!NT_STATUS_IS_OK(status)) {
+ DEBUG(1, ("Failed to start GENSEC mechanism for DCERPC server: auth_type=%d, auth_level=%d: %s\n",
+ (int)auth->auth_info->auth_type,
+ (int)auth->auth_info->auth_level,
+ nt_errstr(status)));
+ return False;
+ }
+
+ return True;
+}
+
+/*
+ add any auth information needed in a bind ack, and process the authentication
+ information found in the bind.
+*/
+NTSTATUS dcesrv_auth_bind_ack(struct dcesrv_call_state *call, struct ncacn_packet *pkt)
+{
+ struct dcesrv_connection *dce_conn = call->conn;
+ NTSTATUS status;
+
+ if (!call->conn->auth_state.gensec_security) {
+ return NT_STATUS_OK;
+ }
+
+ status = gensec_update(dce_conn->auth_state.gensec_security,
+ call,
+ dce_conn->auth_state.auth_info->credentials,
+ &dce_conn->auth_state.auth_info->credentials);
+
+ if (NT_STATUS_IS_OK(status)) {
+ status = gensec_session_info(dce_conn->auth_state.gensec_security,
+ &dce_conn->auth_state.session_info);
+ if (!NT_STATUS_IS_OK(status)) {
+ DEBUG(1, ("Failed to establish session_info: %s\n", nt_errstr(status)));
+ return status;
+ }
+
+ /* Now that we are authenticated, go back to the generic session key... */
+ dce_conn->auth_state.session_key = dcesrv_generic_session_key;
+ return NT_STATUS_OK;
+ } else if (NT_STATUS_EQUAL(status, NT_STATUS_MORE_PROCESSING_REQUIRED)) {
+ dce_conn->auth_state.auth_info->auth_pad_length = 0;
+ dce_conn->auth_state.auth_info->auth_reserved = 0;
+ return NT_STATUS_OK;
+ } else {
+ DEBUG(2, ("Failed to start dcesrv auth negotiate: %s\n", nt_errstr(status)));
+ return status;
+ }
+}
+
+
+/*
+ process the final stage of a auth request
+*/
+BOOL dcesrv_auth_auth3(struct dcesrv_call_state *call)
+{
+ struct ncacn_packet *pkt = &call->pkt;
+ struct dcesrv_connection *dce_conn = call->conn;
+ NTSTATUS status;
+
+ /* We can't work without an existing gensec state, and an new blob to feed it */
+ if (!dce_conn->auth_state.auth_info ||
+ !dce_conn->auth_state.gensec_security ||
+ pkt->u.auth3.auth_info.length == 0) {
+ return False;
+ }
+
+ status = ndr_pull_struct_blob(&pkt->u.auth3.auth_info,
+ call,
+ dce_conn->auth_state.auth_info,
+ (ndr_pull_flags_fn_t)ndr_pull_dcerpc_auth);
+ if (!NT_STATUS_IS_OK(status)) {
+ return False;
+ }
+
+ /* Pass the extra data we got from the client down to gensec for processing */
+ status = gensec_update(dce_conn->auth_state.gensec_security,
+ call,
+ dce_conn->auth_state.auth_info->credentials,
+ &dce_conn->auth_state.auth_info->credentials);
+ if (NT_STATUS_IS_OK(status)) {
+ status = gensec_session_info(dce_conn->auth_state.gensec_security,
+ &dce_conn->auth_state.session_info);
+ if (!NT_STATUS_IS_OK(status)) {
+ DEBUG(1, ("Failed to establish session_info: %s\n", nt_errstr(status)));
+ return False;
+ }
+ /* Now that we are authenticated, go back to the generic session key... */
+ dce_conn->auth_state.session_key = dcesrv_generic_session_key;
+ return True;
+ } else {
+ DEBUG(4, ("dcesrv_auth_auth3: failed to authenticate: %s\n",
+ nt_errstr(status)));
+ return False;
+ }
+
+ return True;
+}
+
+/*
+ parse any auth information from a dcerpc alter request
+ return False if we can't handle the auth request for some
+ reason (in which case we send a bind_nak (is this true for here?))
+*/
+BOOL dcesrv_auth_alter(struct dcesrv_call_state *call)
+{
+ struct ncacn_packet *pkt = &call->pkt;
+ struct dcesrv_connection *dce_conn = call->conn;
+ NTSTATUS status;
+
+ /* on a pure interface change there is no auth blob */
+ if (pkt->u.alter.auth_info.length == 0) {
+ return True;
+ }
+
+ /* We can't work without an existing gensec state */
+ if (!dce_conn->auth_state.gensec_security) {
+ return False;
+ }
+
+ dce_conn->auth_state.auth_info = talloc(dce_conn, struct dcerpc_auth);
+ if (!dce_conn->auth_state.auth_info) {
+ return False;
+ }
+
+ status = ndr_pull_struct_blob(&pkt->u.alter.auth_info,
+ call,
+ dce_conn->auth_state.auth_info,
+ (ndr_pull_flags_fn_t)ndr_pull_dcerpc_auth);
+ if (!NT_STATUS_IS_OK(status)) {
+ return False;
+ }
return True;
}
/*
- add any auth information needed in a bind ack
+ add any auth information needed in a alter ack, and process the authentication
+ information found in the alter.
+*/
+NTSTATUS dcesrv_auth_alter_ack(struct dcesrv_call_state *call, struct ncacn_packet *pkt)
+{
+ struct dcesrv_connection *dce_conn = call->conn;
+ NTSTATUS status;
+
+ /* on a pure interface change there is no auth_info structure
+ setup */
+ if (!call->conn->auth_state.auth_info ||
+ dce_conn->auth_state.auth_info->credentials.length == 0) {
+ return NT_STATUS_OK;
+ }
+
+ if (!call->conn->auth_state.gensec_security) {
+ return NT_STATUS_INVALID_PARAMETER;
+ }
+
+ status = gensec_update(dce_conn->auth_state.gensec_security,
+ call,
+ dce_conn->auth_state.auth_info->credentials,
+ &dce_conn->auth_state.auth_info->credentials);
+
+ if (NT_STATUS_IS_OK(status)) {
+ status = gensec_session_info(dce_conn->auth_state.gensec_security,
+ &dce_conn->auth_state.session_info);
+ if (!NT_STATUS_IS_OK(status)) {
+ DEBUG(1, ("Failed to establish session_info: %s\n", nt_errstr(status)));
+ return status;
+ }
+
+ /* Now that we are authenticated, got back to the generic session key... */
+ dce_conn->auth_state.session_key = dcesrv_generic_session_key;
+ return NT_STATUS_OK;
+ } else if (NT_STATUS_EQUAL(status, NT_STATUS_MORE_PROCESSING_REQUIRED)) {
+ dce_conn->auth_state.auth_info->auth_pad_length = 0;
+ dce_conn->auth_state.auth_info->auth_reserved = 0;
+ return NT_STATUS_OK;
+ }
+
+ DEBUG(2, ("Failed to finish dcesrv auth alter_ack: %s\n", nt_errstr(status)));
+ return status;
+}
+
+/*
+ generate a CONNECT level verifier
*/
-BOOL dcesrv_auth_bind_ack(struct dcesrv_call_state *call, struct dcerpc_packet *pkt)
+static NTSTATUS dcesrv_connect_verifier(TALLOC_CTX *mem_ctx, DATA_BLOB *blob)
{
+ *blob = data_blob_talloc(mem_ctx, NULL, 16);
+ if (blob->data == NULL) {
+ return NT_STATUS_NO_MEMORY;
+ }
+ SIVAL(blob->data, 0, 1);
+ memset(blob->data+4, 0, 12);
+ return NT_STATUS_OK;
+}
+
+/*
+ generate a CONNECT level verifier
+*/
+static NTSTATUS dcesrv_check_connect_verifier(DATA_BLOB *blob)
+{
+ if (blob->length != 16 ||
+ IVAL(blob->data, 0) != 1) {
+ return NT_STATUS_ACCESS_DENIED;
+ }
+ return NT_STATUS_OK;
+}
+
+
+/*
+ check credentials on a request
+*/
+BOOL dcesrv_auth_request(struct dcesrv_call_state *call, DATA_BLOB *full_packet)
+{
+ struct ncacn_packet *pkt = &call->pkt;
+ struct dcesrv_connection *dce_conn = call->conn;
+ DATA_BLOB auth_blob;
+ struct dcerpc_auth auth;
+ struct ndr_pull *ndr;
+ NTSTATUS status;
+
+ if (!dce_conn->auth_state.auth_info ||
+ !dce_conn->auth_state.gensec_security) {
+ return True;
+ }
+
+ auth_blob.length = 8 + pkt->auth_length;
+
+ /* check for a valid length */
+ if (pkt->u.request.stub_and_verifier.length < auth_blob.length) {
+ return False;
+ }
+
+ auth_blob.data =
+ pkt->u.request.stub_and_verifier.data +
+ pkt->u.request.stub_and_verifier.length - auth_blob.length;
+ pkt->u.request.stub_and_verifier.length -= auth_blob.length;
+
+ /* pull the auth structure */
+ ndr = ndr_pull_init_blob(&auth_blob, call);
+ if (!ndr) {
+ return False;
+ }
+
+ if (!(pkt->drep[0] & DCERPC_DREP_LE)) {
+ ndr->flags |= LIBNDR_FLAG_BIGENDIAN;
+ }
+
+ status = ndr_pull_dcerpc_auth(ndr, NDR_SCALARS|NDR_BUFFERS, &auth);
+ if (!NT_STATUS_IS_OK(status)) {
+ talloc_free(ndr);
+ return False;
+ }
+
+ /* check signature or unseal the packet */
+ switch (dce_conn->auth_state.auth_info->auth_level) {
+ case DCERPC_AUTH_LEVEL_PRIVACY:
+ status = gensec_unseal_packet(dce_conn->auth_state.gensec_security,
+ call,
+ full_packet->data + DCERPC_REQUEST_LENGTH,
+ pkt->u.request.stub_and_verifier.length,
+ full_packet->data,
+ full_packet->length-auth.credentials.length,
+ &auth.credentials);
+ memcpy(pkt->u.request.stub_and_verifier.data,
+ full_packet->data + DCERPC_REQUEST_LENGTH,
+ pkt->u.request.stub_and_verifier.length);
+ break;
+
+ case DCERPC_AUTH_LEVEL_INTEGRITY:
+ status = gensec_check_packet(dce_conn->auth_state.gensec_security,
+ call,
+ pkt->u.request.stub_and_verifier.data,
+ pkt->u.request.stub_and_verifier.length,
+ full_packet->data,
+ full_packet->length-auth.credentials.length,
+ &auth.credentials);
+ break;
+
+ case DCERPC_AUTH_LEVEL_CONNECT:
+ status = dcesrv_check_connect_verifier(&auth.credentials);
+ break;
+
+ default:
+ status = NT_STATUS_INVALID_LEVEL;
+ break;
+ }
+
+ /* remove the indicated amount of padding */
+ if (pkt->u.request.stub_and_verifier.length < auth.auth_pad_length) {
+ talloc_free(ndr);
+ return False;
+ }
+ pkt->u.request.stub_and_verifier.length -= auth.auth_pad_length;
+ talloc_free(ndr);
+
+ return NT_STATUS_IS_OK(status);
+}
+
+
+/*
+ push a signed or sealed dcerpc request packet into a blob
+*/
+BOOL dcesrv_auth_response(struct dcesrv_call_state *call,
+ DATA_BLOB *blob, struct ncacn_packet *pkt)
+{
+ struct dcesrv_connection *dce_conn = call->conn;
+ NTSTATUS status;
+ struct ndr_push *ndr;
+ uint32_t payload_length;
+ DATA_BLOB creds2;
+
+ /* non-signed packets are simple */
+ if (!dce_conn->auth_state.auth_info || !dce_conn->auth_state.gensec_security) {
+ status = ncacn_push_auth(blob, call, pkt, NULL);
+ return NT_STATUS_IS_OK(status);
+ }
+
+ ndr = ndr_push_init_ctx(call);
+ if (!ndr) {
+ return False;
+ }
+
+ if (!(pkt->drep[0] & DCERPC_DREP_LE)) {
+ ndr->flags |= LIBNDR_FLAG_BIGENDIAN;
+ }
+
+ status = ndr_push_ncacn_packet(ndr, NDR_SCALARS|NDR_BUFFERS, pkt);
+ if (!NT_STATUS_IS_OK(status)) {
+ return False;
+ }
+
+ /* pad to 16 byte multiple, match win2k3 */
+ dce_conn->auth_state.auth_info->auth_pad_length = NDR_ALIGN(ndr, 16);
+ ndr_push_zero(ndr, dce_conn->auth_state.auth_info->auth_pad_length);
+
+ payload_length = ndr->offset - DCERPC_REQUEST_LENGTH;
+
+ if (dce_conn->auth_state.auth_info->auth_level == DCERPC_AUTH_LEVEL_CONNECT) {
+ status = dcesrv_connect_verifier(call,
+ &dce_conn->auth_state.auth_info->credentials);
+ if (!NT_STATUS_IS_OK(status)) {
+ return False;
+ }
+ } else {
+
+ /* We hope this length is accruate. If must be if the
+ * GENSEC mech does AEAD signing of the packet
+ * headers */
+ dce_conn->auth_state.auth_info->credentials
+ = data_blob_talloc(call, NULL,
+ gensec_sig_size(dce_conn->auth_state.gensec_security,
+ payload_length));
+ data_blob_clear(&dce_conn->auth_state.auth_info->credentials);
+ }
+
+ /* add the auth verifier */
+ status = ndr_push_dcerpc_auth(ndr, NDR_SCALARS|NDR_BUFFERS,
+ dce_conn->auth_state.auth_info);
+ if (!NT_STATUS_IS_OK(status)) {
+ return False;
+ }
+
+ /* extract the whole packet as a blob */
+ *blob = ndr_push_blob(ndr);
+
+ /* fill in the fragment length and auth_length, we can't fill
+ in these earlier as we don't know the signature length (it
+ could be variable length) */
+ dcerpc_set_frag_length(blob, blob->length);
+
+ /* We hope this value is accruate. If must be if the GENSEC
+ * mech does AEAD signing of the packet headers */
+ dcerpc_set_auth_length(blob, dce_conn->auth_state.auth_info->credentials.length);
+
+ /* sign or seal the packet */
+ switch (dce_conn->auth_state.auth_info->auth_level) {
+ case DCERPC_AUTH_LEVEL_PRIVACY:
+ status = gensec_seal_packet(dce_conn->auth_state.gensec_security,
+ call,
+ ndr->data + DCERPC_REQUEST_LENGTH,
+ payload_length,
+ blob->data,
+ blob->length - dce_conn->auth_state.auth_info->credentials.length,
+ &creds2);
+
+ if (NT_STATUS_IS_OK(status)) {
+ blob->length -= dce_conn->auth_state.auth_info->credentials.length;
+ if (!data_blob_append(call, blob, creds2.data, creds2.length))
+ status = NT_STATUS_NO_MEMORY;
+ else
+ status = NT_STATUS_OK;
+ }
+
+ /* If we did AEAD signing of the packet headers, then we hope
+ * this value didn't change... */
+ dcerpc_set_auth_length(blob, creds2.length);
+ dcerpc_set_frag_length(blob, dcerpc_get_frag_length(blob)+creds2.length);
+ data_blob_free(&creds2);
+ break;
+
+ case DCERPC_AUTH_LEVEL_INTEGRITY:
+ status = gensec_sign_packet(dce_conn->auth_state.gensec_security,
+ call,
+ ndr->data + DCERPC_REQUEST_LENGTH,
+ payload_length,
+ blob->data,
+ blob->length - dce_conn->auth_state.auth_info->credentials.length,
+ &creds2);
+ if (NT_STATUS_IS_OK(status)) {
+ blob->length -= dce_conn->auth_state.auth_info->credentials.length;
+ if (!data_blob_append(call, blob, creds2.data, creds2.length))
+ status = NT_STATUS_NO_MEMORY;
+ else
+ status = NT_STATUS_OK;
+ }
+
+ /* If we did AEAD signing of the packet headers, then we hope
+ * this value didn't change... */
+ dcerpc_set_auth_length(blob, creds2.length);
+ dcerpc_set_frag_length(blob, dcerpc_get_frag_length(blob)+creds2.length);
+ data_blob_free(&creds2);
+ break;
+
+ case DCERPC_AUTH_LEVEL_CONNECT:
+ break;
+
+ default:
+ status = NT_STATUS_INVALID_LEVEL;
+ break;
+ }
+
+ data_blob_free(&dce_conn->auth_state.auth_info->credentials);
+
+ if (!NT_STATUS_IS_OK(status)) {
+ return False;
+ }
+
return True;
}
git.samba.org / kai / samba-autobuild / .git / blobdiff