r11906: opcode 13 appears to be keepalive. Metze guessed this one :-)

source/libcli/smb2/config.mk

@@ -16,5 +16,6 @@ OBJ_FILES = \
 	trans.o \
 	logoff.o \
 	tdis.o \
-	flush.o
+	flush.o \
+	keepalive.o
 REQUIRED_SUBSYSTEMS = LIBCLI_RAW LIBPACKET

source/libcli/smb2/keepalive.c

@@ -0,0 +1,67 @@
+/* 
+   Unix SMB/CIFS implementation.
+
+   SMB2 client keepalive handling
+
+   Copyright (C) Andrew Tridgell 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 2 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, write to the Free Software
+   Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
+*/
+
+#include "includes.h"
+#include "libcli/raw/libcliraw.h"
+#include "libcli/smb2/smb2.h"
+#include "libcli/smb2/smb2_calls.h"
+
+/*
+  send a keepalive request
+*/
+struct smb2_request *smb2_keepalive_send(struct smb2_tree *tree)
+{
+	struct smb2_request *req;
+
+	req = smb2_request_init_tree(tree, SMB2_OP_KEEPALIVE, 0x04, 0);
+	if (req == NULL) return NULL;
+
+	SSVAL(req->out.body, 0x02, 0);
+
+	smb2_transport_send(req);
+
+	return req;
+}
+
+
+/*
+  recv a keepalive reply
+*/
+NTSTATUS smb2_keepalive_recv(struct smb2_request *req)
+{
+	if (!smb2_request_receive(req) || 
+	    smb2_request_is_error(req)) {
+		return smb2_request_destroy(req);
+	}
+
+	SMB2_CHECK_PACKET_RECV(req, 0x04, False);
+	return smb2_request_destroy(req);
+}
+
+/*
+  sync keepalive request
+*/
+NTSTATUS smb2_keepalive(struct smb2_tree *tree)
+{
+	struct smb2_request *req = smb2_keepalive_send(tree);
+	return smb2_keepalive_recv(req);
+}

source/libcli/smb2/smb2.h

@@ -169,6 +169,7 @@ struct smb2_request {
 #define SMB2_OP_WRITE     0x09
 #define SMB2_OP_TRANS     0x0b
 #define SMB2_OP_CANCEL    0x0c
+#define SMB2_OP_KEEPALIVE 0x0d
 #define SMB2_OP_FIND      0x0e
 #define SMB2_OP_NOTIFY    0x0f
 #define SMB2_OP_GETINFO   0x10