1 files changed, 327 insertions, 0 deletions

diff --git a/source4/smb_server/smb2/negprot.c b/source4/smb_server/smb2/negprot.c
new file mode 100644
index 0000000..048d7b4
--- /dev/null
+++ b/source4/smb_server/smb2/negprot.c
@@ -0,0 +1,327 @@
+/* 
+   Unix SMB2 implementation.
+   
+   Copyright (C) Andrew Bartlett	2001-2005
+   Copyright (C) Stefan Metzmacher	2005
+   
+   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/credentials/credentials.h"
+#include "auth/auth.h"
+#include "auth/gensec/gensec.h"
+#include "libcli/raw/libcliraw.h"
+#include "libcli/raw/raw_proto.h"
+#include "libcli/smb2/smb2.h"
+#include "libcli/smb2/smb2_calls.h"
+#include "smb_server/smb_server.h"
+#include "smb_server/smb2/smb2_server.h"
+#include "samba/service_stream.h"
+#include "param/param.h"
+
+static NTSTATUS smb2srv_negprot_secblob(struct smb2srv_request *req, DATA_BLOB *_blob)
+{
+	struct gensec_security *gensec_security;
+	DATA_BLOB null_data_blob = data_blob(NULL, 0);
+	DATA_BLOB blob;
+	NTSTATUS nt_status;
+	struct cli_credentials *server_credentials;
+
+	server_credentials =
+		cli_credentials_init_server(req, req->smb_conn->lp_ctx);
+	if (server_credentials == NULL) {
+		DBG_DEBUG("Failed to obtain server credentials, "
+			  "perhaps a standalone server?\n");
+		/*
+		 * Create anon server credentials for for the
+		 * spoolss.notify test.
+		 */
+		server_credentials = cli_credentials_init_anon(req);
+		if (server_credentials == NULL) {
+			smbsrv_terminate_connection(req->smb_conn,
+				"Failed to init server credentials\n");
+			return NT_STATUS_NO_MEMORY;
+		}
+	}
+
+	req->smb_conn->negotiate.server_credentials = talloc_steal(req->smb_conn, server_credentials);
+
+	nt_status = samba_server_gensec_start(req,
+					      req->smb_conn->connection->event.ctx,
+					      req->smb_conn->connection->msg_ctx,
+					      req->smb_conn->lp_ctx,
+					      server_credentials,
+					      "cifs",
+					      &gensec_security);
+	if (!NT_STATUS_IS_OK(nt_status)) {
+		DEBUG(0, ("Failed to start GENSEC: %s\n", nt_errstr(nt_status)));
+		smbsrv_terminate_connection(req->smb_conn, "Failed to start GENSEC\n");
+		return nt_status;
+	}
+
+	gensec_set_target_service(gensec_security, "cifs");
+
+	gensec_set_credentials(gensec_security, server_credentials);
+
+	nt_status = gensec_start_mech_by_oid(gensec_security, GENSEC_OID_SPNEGO);
+	if (!NT_STATUS_IS_OK(nt_status)) {
+		DEBUG(0, ("Failed to start SPNEGO: %s\n", nt_errstr(nt_status)));
+		smbsrv_terminate_connection(req->smb_conn, "Failed to start SPNEGO\n");
+		return nt_status;
+	}
+
+	nt_status = gensec_update(gensec_security, req,
+				  null_data_blob, &blob);
+	if (!NT_STATUS_IS_OK(nt_status) && !NT_STATUS_EQUAL(nt_status, NT_STATUS_MORE_PROCESSING_REQUIRED)) {
+		DEBUG(0, ("Failed to get SPNEGO to give us the first token: %s\n", nt_errstr(nt_status)));
+		smbsrv_terminate_connection(req->smb_conn, "Failed to start SPNEGO - no first token\n");
+		return nt_status;
+	}
+
+	*_blob = blob;
+	return NT_STATUS_OK;
+}
+
+static NTSTATUS smb2srv_negprot_backend(struct smb2srv_request *req, struct smb2_negprot *io)
+{
+	NTSTATUS status;
+	struct timeval current_time;
+	struct timeval boot_time;
+	uint16_t i;
+	uint16_t dialect = 0;
+	enum smb_signing_setting signing_setting;
+	struct loadparm_context *lp_ctx = req->smb_conn->lp_ctx;
+
+	/* we only do one dialect for now */
+	if (io->in.dialect_count < 1) {
+		return NT_STATUS_NOT_SUPPORTED;
+	}
+	for (i=0; i < io->in.dialect_count; i++) {
+		dialect = io->in.dialects[i];
+		if (dialect == SMB2_DIALECT_REVISION_202) {
+			break;
+		}
+	}
+	if (dialect != SMB2_DIALECT_REVISION_202) {
+		DEBUG(0,("Got unexpected SMB2 dialect %u\n", dialect));
+		return NT_STATUS_NOT_SUPPORTED;
+	}
+
+	req->smb_conn->negotiate.protocol = PROTOCOL_SMB2_02;
+
+	current_time = timeval_current(); /* TODO: handle timezone?! */
+	boot_time = timeval_current(); /* TODO: fix me */
+
+	ZERO_STRUCT(io->out);
+
+	signing_setting = lpcfg_server_signing(lp_ctx);
+	if (signing_setting == SMB_SIGNING_DEFAULT) {
+		/*
+		 * If we are a domain controller, SMB signing is
+		 * really important, as it can prevent a number of
+		 * attacks on communications between us and the
+		 * clients
+		 *
+		 * However, it really sucks (no sendfile, CPU
+		 * overhead) performance-wise when used on a
+		 * file server, so disable it by default
+		 * on non-DCs
+		 */
+
+		if (lpcfg_server_role(lp_ctx) >= ROLE_ACTIVE_DIRECTORY_DC) {
+			signing_setting = SMB_SIGNING_REQUIRED;
+		} else {
+			signing_setting = SMB_SIGNING_OFF;
+		}
+	}
+
+	switch (signing_setting) {
+	case SMB_SIGNING_DEFAULT:
+	case SMB_SIGNING_IPC_DEFAULT:
+		smb_panic(__location__);
+		break;
+	case SMB_SIGNING_OFF:
+		io->out.security_mode = 0;
+		break;
+	case SMB_SIGNING_DESIRED:
+	case SMB_SIGNING_IF_REQUIRED:
+		io->out.security_mode = SMB2_NEGOTIATE_SIGNING_ENABLED;
+		break;
+	case SMB_SIGNING_REQUIRED:
+		io->out.security_mode = SMB2_NEGOTIATE_SIGNING_ENABLED | SMB2_NEGOTIATE_SIGNING_REQUIRED;
+		/* force signing on immediately */
+		req->smb_conn->smb2_signing_required = true;
+		break;
+	}
+	io->out.dialect_revision   = dialect;
+	io->out.capabilities       = 0;
+	io->out.max_transact_size  = lpcfg_parm_ulong(req->smb_conn->lp_ctx, NULL,
+						   "smb2", "max transaction size", 0x10000);
+	io->out.max_read_size      = lpcfg_parm_ulong(req->smb_conn->lp_ctx, NULL,
+						   "smb2", "max read size", 0x10000);
+	io->out.max_write_size     = lpcfg_parm_ulong(req->smb_conn->lp_ctx, NULL,
+						   "smb2", "max write size", 0x10000);
+	io->out.system_time	   = timeval_to_nttime(&current_time);
+	io->out.server_start_time  = timeval_to_nttime(&boot_time);
+	io->out.reserved2          = 0;
+	status = smb2srv_negprot_secblob(req, &io->out.secblob);
+	NT_STATUS_NOT_OK_RETURN(status);
+
+	return NT_STATUS_OK;
+}
+
+static void smb2srv_negprot_send(struct smb2srv_request *req, struct smb2_negprot *io)
+{
+	NTSTATUS status;
+
+	if (NT_STATUS_IS_ERR(req->status)) {
+		smb2srv_send_error(req, req->status); /* TODO: is this correct? */
+		return;
+	}
+
+	status = smb2srv_setup_reply(req, 0x40, true, io->out.secblob.length);
+	if (!NT_STATUS_IS_OK(status)) {
+		smbsrv_terminate_connection(req->smb_conn, nt_errstr(status));
+		talloc_free(req);
+		return;
+	}
+
+	SSVAL(req->out.body, 0x02, io->out.security_mode);
+	SIVAL(req->out.body, 0x04, io->out.dialect_revision);
+	SIVAL(req->out.body, 0x06, io->out.reserved);
+	status = smbcli_push_guid(req->out.body, 0x08, &io->out.server_guid);
+	if (!NT_STATUS_IS_OK(status)) {
+		smbsrv_terminate_connection(req->smb_conn, nt_errstr(status));
+		talloc_free(req);
+		return;
+	}
+	SIVAL(req->out.body, 0x18, io->out.capabilities);
+	SIVAL(req->out.body, 0x1C, io->out.max_transact_size);
+	SIVAL(req->out.body, 0x20, io->out.max_read_size);
+	SIVAL(req->out.body, 0x24, io->out.max_write_size);
+	push_nttime(req->out.body, 0x28, io->out.system_time);
+	push_nttime(req->out.body, 0x30, io->out.server_start_time);
+	SIVAL(req->out.body, 0x3C, io->out.reserved2);
+	status = smb2_push_o16s16_blob(&req->out, 0x38, io->out.secblob);
+	if (!NT_STATUS_IS_OK(status)) {
+		smbsrv_terminate_connection(req->smb_conn, nt_errstr(status));
+		talloc_free(req);
+		return;
+	}
+
+	smb2srv_send_reply(req);
+}
+
+void smb2srv_negprot_recv(struct smb2srv_request *req)
+{
+	struct smb2_negprot *io;
+	int i;
+
+	if (req->in.body_size < 0x26) {
+		smbsrv_terminate_connection(req->smb_conn, "Bad body size in SMB2 negprot");
+		return;
+	}
+
+	io = talloc(req, struct smb2_negprot);
+	if (!io) {
+		smbsrv_terminate_connection(req->smb_conn, nt_errstr(NT_STATUS_NO_MEMORY));
+		talloc_free(req);
+		return;
+	}
+
+	io->in.dialect_count = SVAL(req->in.body, 0x02);
+	io->in.security_mode = SVAL(req->in.body, 0x04);
+	io->in.reserved      = SVAL(req->in.body, 0x06);
+	io->in.capabilities  = IVAL(req->in.body, 0x08);
+	req->status = smbcli_pull_guid(req->in.body, 0xC, &io->in.client_guid);
+	if (!NT_STATUS_IS_OK(req->status)) {
+		smbsrv_terminate_connection(req->smb_conn, "Bad GUID in SMB2 negprot");
+		talloc_free(req);
+		return;
+	}
+	io->in.start_time = smbcli_pull_nttime(req->in.body, 0x1C);
+
+	io->in.dialects = talloc_array(req, uint16_t, io->in.dialect_count);
+	if (io->in.dialects == NULL) {
+		smbsrv_terminate_connection(req->smb_conn, nt_errstr(NT_STATUS_NO_MEMORY));
+		talloc_free(req);
+		return;
+	}
+	for (i=0;i<io->in.dialect_count;i++) {
+		io->in.dialects[i] = SVAL(req->in.body, 0x24+i*2);
+	}
+
+	req->status = smb2srv_negprot_backend(req, io);
+
+	if (req->control_flags & SMB2SRV_REQ_CTRL_FLAG_NOT_REPLY) {
+		talloc_free(req);
+		return;
+	}
+	smb2srv_negprot_send(req, io);
+}
+
+/*
+ * reply to a SMB negprot request with dialect "SMB 2.002"
+ */
+void smb2srv_reply_smb_negprot(struct smbsrv_request *smb_req)
+{
+	struct smb2srv_request *req;
+	uint32_t body_fixed_size = 0x26;
+
+	req = talloc_zero(smb_req->smb_conn, struct smb2srv_request);
+	if (!req) goto nomem;
+	req->smb_conn		= smb_req->smb_conn;
+	req->request_time	= smb_req->request_time;
+	talloc_steal(req, smb_req);
+
+	req->in.size      = NBT_HDR_SIZE+SMB2_HDR_BODY+body_fixed_size;
+	req->in.allocated = req->in.size;
+	req->in.buffer    = talloc_array(req, uint8_t, req->in.allocated);
+	if (!req->in.buffer) goto nomem;
+	req->in.hdr       = req->in.buffer + NBT_HDR_SIZE;
+	req->in.body      = req->in.hdr + SMB2_HDR_BODY;
+	req->in.body_size = body_fixed_size;
+	req->in.dynamic   = NULL;
+
+	smb2srv_setup_bufinfo(req);
+
+	SIVAL(req->in.hdr, 0,				SMB2_MAGIC);
+	SSVAL(req->in.hdr, SMB2_HDR_LENGTH,		SMB2_HDR_BODY);
+	SSVAL(req->in.hdr, SMB2_HDR_EPOCH,		0);
+	SIVAL(req->in.hdr, SMB2_HDR_STATUS,		0);
+	SSVAL(req->in.hdr, SMB2_HDR_OPCODE,		SMB2_OP_NEGPROT);
+	SSVAL(req->in.hdr, SMB2_HDR_CREDIT,		0);
+	SIVAL(req->in.hdr, SMB2_HDR_FLAGS,		0);
+	SIVAL(req->in.hdr, SMB2_HDR_NEXT_COMMAND,	0);
+	SBVAL(req->in.hdr, SMB2_HDR_MESSAGE_ID,		0);
+	SIVAL(req->in.hdr, SMB2_HDR_PID,		0);
+	SIVAL(req->in.hdr, SMB2_HDR_TID,		0);
+	SBVAL(req->in.hdr, SMB2_HDR_SESSION_ID,		0);
+	memset(req->in.hdr+SMB2_HDR_SIGNATURE, 0, 16);
+
+	/* this seems to be a bug, they use 0x24 but the length is 0x26 */
+	SSVAL(req->in.body, 0x00, 0x24);
+
+	SSVAL(req->in.body, 0x02, 1);
+	memset(req->in.body+0x04, 0, 32);
+	SSVAL(req->in.body, 0x24, SMB2_DIALECT_REVISION_202);
+
+	smb2srv_negprot_recv(req);
+	return;
+nomem:
+	smbsrv_terminate_connection(smb_req->smb_conn, nt_errstr(NT_STATUS_NO_MEMORY));
+	talloc_free(req);
+	return;
+}