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Wireshark-dev: Re: [Wireshark-dev] MAPI EcrRegisterPushNotification dissection

From: Stephen Fisher <stephentfisher@xxxxxxxxx>
Date: Wed, 27 Sep 2006 10:58:13 -0700
On Fri, Sep 22, 2006 at 02:42:10PM -0700, Stephen Fisher wrote:

> I have figured out one of the fields in the MAPI 
> EcRRegisterPushNotification packet.  The field is a UDP port number 
> that the client wants the Exchange server to send new mail 
> notifications on.  These notifications are on a port > 1023 and are 
> always 8 bytes long.

Here is a patch to add this functionality.  It displays the notification 
port and the notification payload (not sure what the payload itself 
means yet).  It also dynamically registers each notification port found 
with a new dissector (that I called newmail for lack of a better name - 
I'm open to suggestions) that displays the notification payload.  This 
is all undocumented by Microsoft in their usual fashion.

I also changed the code to always display the mapi.opnum field; 
currently, the mapi.opnum is only displayed when the 
dcerpc_mapi_dissector is null.


Steve
Index: epan/dissectors/Makefile.common
===================================================================
--- epan/dissectors/Makefile.common	(revision 19338)
+++ epan/dissectors/Makefile.common	(working copy)
@@ -478,6 +478,7 @@
 	packet-netflow.c	\
 	packet-netsync.c \
 	packet-nettl.c	\
+	packet-newmail.c	\
 	packet-nfs.c	\
 	packet-nfsacl.c	\
 	packet-nfsauth.c	\
Index: epan/dissectors/packet-dcerpc.c
===================================================================
--- epan/dissectors/packet-dcerpc.c	(revision 19338)
+++ epan/dissectors/packet-dcerpc.c	(working copy)
@@ -2192,18 +2192,16 @@
          * Put the operation number into the tree along with
          * the operation's name.
          */
-        if(sub_dissect == NULL) {
-	    if (sub_proto->opnum_hf != -1)
+	if (sub_proto->opnum_hf != -1)
                 proto_tree_add_uint_format(sub_tree, sub_proto->opnum_hf,
                                            tvb, 0, 0, info->call_data->opnum,
                                            "Operation: %s (%u)",
                                            name, info->call_data->opnum);
-            else
+	else
                 proto_tree_add_uint_format(sub_tree, hf_dcerpc_op, tvb,
                                            0, 0, info->call_data->opnum,
                                            "Operation: %s (%u)",
                                            name, info->call_data->opnum);
-	}
 
         if(info->ptype == PDU_REQ && info->call_data->rep_frame!=0) {
             pi = proto_tree_add_uint(sub_tree, hf_dcerpc_response_in,
Index: epan/dissectors/packet-dcerpc-mapi.c
===================================================================
--- epan/dissectors/packet-dcerpc-mapi.c	(revision 19338)
+++ epan/dissectors/packet-dcerpc-mapi.c	(working copy)
@@ -49,6 +49,8 @@
 static int hf_mapi_decrypted_data_len = -1;
 static int hf_mapi_decrypted_data = -1;
 static int hf_mapi_pdu_len = -1;
+static int hf_mapi_notification_port = -1;
+static int hf_mapi_notification_payload = -1;
 
 static gint ett_dcerpc_mapi = -1;
 static gint ett_mapi_decrypted_pdu = -1;
@@ -290,7 +292,26 @@
 	return offset;
 }
 
+static int
+mapi_reg_push_notification_rqst(tvbuff_t *tvb, int offset,
+	packet_info *pinfo _U_, proto_tree *tree, guint8 *drep _U_)
+{
+	static dissector_handle_t newmail_handle;
 
+	proto_tree_add_item(tree, hf_mapi_notification_payload, tvb, 28, 8,
+			    FALSE);
+	proto_tree_add_item(tree, hf_mapi_notification_port, tvb, 50, 2,
+			    FALSE);
+
+	/* Register the notification port from this packet with the newmail
+	   dissector. */
+	newmail_handle = find_dissector("newmail");
+	dissector_add("udp.port", tvb_get_ntohs(tvb, 50), newmail_handle);
+
+	offset = 52;
+	return offset;
+}
+
 static dcerpc_sub_dissector dcerpc_mapi_dissectors[] = {
         { MAPI_EC_DO_CONNECT,	"EcDoConnect",
 		mapi_logon_rqst,
@@ -303,13 +324,13 @@
 		mapi_ec_do_rpc_reply },
 	{ MAPI_EC_GET_MORE_RPC, "EcGetMoreRpc", NULL, NULL },
 	{ MAPI_EC_REGISTER_PUSH_NOTIFICATION, "EcRRegisterPushNotification",
-		NULL, NULL },
+		mapi_reg_push_notification_rqst, NULL },
 	{ MAPI_EC_UNREGISTER_PUSH_NOTIFICATION, "EcRUnregisterPushNotification",
-		NULL, NULL },
+	        NULL, NULL }, /* Not used by Microsoft Outlook */
 	{ MAPI_EC_DUMMY_RPC, "EcDummyRpc", NULL, NULL },
 	{ MAPI_EC_GET_DC_NAME, "EcRGetDCName", NULL, NULL },
  	{ MAPI_EC_NET_GET_DC_NAME, "EcRNetGetDCName", NULL, NULL },
 	{ MAPI_EC_DO_RPC_EXT, "EcDoRpcExt", NULL, NULL },
 };
 
 void
@@ -370,6 +391,16 @@
 		{ "Length", "mapi.pdu.len", FT_UINT16, BASE_DEC,
 		NULL, 0x0, "Size of the command PDU", HFILL }},
 
+	{ &hf_mapi_notification_port,
+		{ "Notification port", "mapi.notification_port", FT_UINT16,
+		  BASE_DEC, NULL, 0x0,
+		  "UDP port which newmail protocol notifications are sent to on the client", HFILL }},
+
+	{ &hf_mapi_notification_payload,
+		{ "Notification payload", "mapi.notification_payload",
+		  FT_BYTES, BASE_NONE, NULL, 0x0,
+		  "Payload to be sent in newmail protocol notification packets", HFILL }},
+
 	};
 
 
Index: epan/dissectors/packet-newmail.c
===================================================================
--- epan/dissectors/packet-newmail.c	(revision 0)
+++ epan/dissectors/packet-newmail.c	(revision 0)
@@ -0,0 +1,148 @@
+/* packet-newmail.c
+ * Routines for Exchange New Mail Notification dissection
+ * Copyright 2006, Stephen Fisher <stephentfisher@xxxxxxxxx>
+ *
+ * $Id: README.developer 19070 2006-08-29 00:15:09Z ulfl $
+ *
+ * Wireshark - Network traffic analyzer
+ * By Gerald Combs <gerald@xxxxxxxxxxxxx>
+ * Copyright 1998 Gerald Combs
+ *
+ * Copied from WHATEVER_FILE_YOU_USED (where "WHATEVER_FILE_YOU_USED"
+ * is a dissector file; if you just copied this from README.developer,
+ * don't bother with the "Copied from" - you don't even need to put
+ * in a "Copied from" if you copied an existing dissector, especially
+ * if the bulk of the code in the new dissector is your code)
+ * 
+ * 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., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
+ */
+
+#ifdef HAVE_CONFIG_H
+# include "config.h"
+#endif
+
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+
+#include <glib.h>
+
+#include <epan/packet.h>
+#include <epan/prefs.h>
+
+/* Forward declaration we need below */
+void proto_reg_handoff_newmail(void);
+
+/* Variables for preferences */
+guint16 preference_default_port = 0;
+guint16 preference_default_port_last = 0;
+
+/* Initialize the protocol and registered fields */
+static int proto_newmail = -1;
+static int hf_newmail_payload = -1;
+
+/* Initialize the subtree pointers */
+static gint ett_newmail = -1;
+
+/* Code to actually dissect the packets */
+static void
+dissect_newmail(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree)
+{
+	/* Set up structures needed to add the protocol subtree and manage it */
+	proto_item *ti;
+	proto_tree *newmail_tree;
+
+	/* Make entries in Protocol column and Info column on summary display */
+	if (check_col(pinfo->cinfo, COL_PROTOCOL)) 
+		col_set_str(pinfo->cinfo, COL_PROTOCOL, "NEWMAIL");
+
+	if (check_col(pinfo->cinfo, COL_INFO)) 
+		col_set_str(pinfo->cinfo, COL_INFO, "Microsoft Exchange new mail notification");
+
+	if (tree) {
+		ti = proto_tree_add_item(tree, proto_newmail, tvb, 0, -1, FALSE);
+
+		newmail_tree = proto_item_add_subtree(ti, ett_newmail);
+
+		proto_tree_add_item(newmail_tree, hf_newmail_payload, tvb, 0, 8, FALSE);
+	}
+}
+
+
+/* Register the protocol with Wireshark */
+void
+proto_register_newmail(void)
+{                 
+
+	/* Setup list of header fields  See Section 1.6.1 for details*/
+	static hf_register_info hf[] = {
+		{ &hf_newmail_payload,
+		  { "Notification payload", "newmail.notification_payload",
+		    FT_BYTES, BASE_NONE, NULL, 0x0,          
+		    "Payload requested by client in the MAPI register push notification packet", HFILL }
+		},
+	};
+
+	/* Setup protocol subtree array */
+	static gint *ett[] = {
+		&ett_newmail,
+	};
+
+	module_t *newmail_module;
+
+	/* Register the protocol name and description */
+	proto_newmail = proto_register_protocol("Microsoft Exchange New Mail Notification",
+						"NEWMAIL", "newmail");
+
+	/* Required function calls to register the header fields and subtrees used */
+	proto_register_field_array(proto_newmail, hf, array_length(hf));
+	proto_register_subtree_array(ett, array_length(ett));
+
+	/* Register the dissector without a port yet */
+	register_dissector("newmail", dissect_newmail, proto_newmail);
+        
+	/* Register preferences module */
+	newmail_module = prefs_register_protocol(proto_newmail,
+						 proto_reg_handoff_newmail);
+
+	prefs_register_uint_preference(newmail_module,
+				       "default_port",
+				       "Default UDP port (optional)",
+				       "Always dissect this port's traffic as newmail notifications.  Additional ports will be dynamically registered as they are seen in MAPI register push notification packets.",
+				       10, &preference_default_port);
+	
+}
+
+void
+proto_reg_handoff_newmail(void)
+{
+	dissector_handle_t newmail_handle;
+
+	newmail_handle = find_dissector("newmail");
+	
+	if(preference_default_port != preference_default_port_last) {	
+		/* Unregister the last setting */
+		dissector_delete("udp.port", preference_default_port_last,
+				 newmail_handle);
+		
+		/* Save the last setting so we can unregister it later */
+		preference_default_port_last = preference_default_port;
+		
+		/* Register the new setting */
+		dissector_add("udp.port", preference_default_port, newmail_handle);
+	}
+	
+
+}