From Christian Falckenberg: beginnings of a MEGACO dissector.

Move SCTP payload protocol IDs to a header file, and get the PPIDs from
that header file rather than defining them in dissectors running atop
SCTP.  Use both the old(?) and official PPID for ASAP.


git-svn-id: http://anonsvn.wireshark.org/wireshark/trunk@6926 f5534014-38df-0310-8fa8-9805f1628bb7

10 files changed, 853 insertions, 0 deletions

diff --git a/plugins/megaco/.cvsignore b/plugins/megaco/.cvsignore
new file mode 100644
index 0000000000..94009a655e
--- /dev/null
+++ b/plugins/megaco/.cvsignore
@@ -0,0 +1,19 @@
+.deps
+.libs
+Makefile
+Makefile.in
+config.cache
+config.h
+config.h.in
+config.log
+config.status
+configure
+megaco.la
+packet-megaco.lo
+packet-megaco-static.lo
+stamp-h
+*.obj
+*.dll
+*.exp
+*.lib
+*.pdb
diff --git a/plugins/megaco/AUTHORS b/plugins/megaco/AUTHORS
new file mode 100644
index 0000000000..6737b0c5c8
--- /dev/null
+++ b/plugins/megaco/AUTHORS
@@ -0,0 +1,3 @@
+Author:
+Christian Falckenberg <christian.falckenberg@nortelnetworks.com>
+
diff --git a/plugins/megaco/COPYING b/plugins/megaco/COPYING
new file mode 100644
index 0000000000..d60c31a97a
--- /dev/null
+++ b/plugins/megaco/COPYING
@@ -0,0 +1,340 @@
+		    GNU GENERAL PUBLIC LICENSE
+		       Version 2, June 1991
+
+ Copyright (C) 1989, 1991 Free Software Foundation, Inc.
+     59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
+ Everyone is permitted to copy and distribute verbatim copies
+ of this license document, but changing it is not allowed.
+
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+
+  <signature of Ty Coon>, 1 April 1989
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+proprietary programs.  If your program is a subroutine library, you may
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+library.  If this is what you want to do, use the GNU Library General
+Public License instead of this License.
diff --git a/plugins/megaco/ChangeLog b/plugins/megaco/ChangeLog
new file mode 100644
index 0000000000..e69de29bb2
--- /dev/null
+++ b/plugins/megaco/ChangeLog
diff --git a/plugins/megaco/INSTALL b/plugins/megaco/INSTALL
new file mode 100644
index 0000000000..e69de29bb2
--- /dev/null
+++ b/plugins/megaco/INSTALL
diff --git a/plugins/megaco/Makefile.am b/plugins/megaco/Makefile.am
new file mode 100644
index 0000000000..d7465c8bed
--- /dev/null
+++ b/plugins/megaco/Makefile.am
@@ -0,0 +1,48 @@
+# Makefile.am
+# Automake file for Megaco Ethereal plugin
+#
+# $Id: Makefile.am,v 1.1 2003/01/14 23:53:40 guy Exp $
+#
+# Ethereal - Network traffic analyzer
+# By Gerald Combs <gerald@ethereal.com>
+# Copyright 1998 Gerald Combs
+# 
+# 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.
+#
+
+INCLUDES = -I$(top_srcdir)
+
+plugindir = @plugindir@
+
+plugin_LTLIBRARIES = megaco.la
+megaco_la_SOURCES = packet-megaco.c moduleinfo.h
+megaco_la_LDFLAGS = -module -avoid-version
+
+# Libs must be cleared, or else libtool won't create a shared module.
+# If your module needs to be linked against any particular libraries,
+# add them here.
+LIBS =
+
+megaco_la_DEPENDENCIES = packet-megaco-static.o
+
+packet-megaco-static.o:	packet-megaco.c moduleinfo.h
+	$(LTCOMPILE) -c -o packet-megaco-static.o -D__ETHEREAL_STATIC__ $(srcdir)/packet-megaco.c 
+
+CLEANFILES = \
+	megaco \
+	*~
+
+EXTRA_DIST = \
+	Makefile.nmake
diff --git a/plugins/megaco/Makefile.nmake b/plugins/megaco/Makefile.nmake
new file mode 100644
index 0000000000..068a880e0f
--- /dev/null
+++ b/plugins/megaco/Makefile.nmake
@@ -0,0 +1,21 @@
+#
+# $Id: Makefile.nmake,v 1.1 2003/01/14 23:53:40 guy Exp $
+#
+
+include ..\..\config.nmake
+
+############### no need to modify below this line #########
+
+CFLAGS=/DHAVE_CONFIG_H /I../.. /I../../wiretap \
+	/I$(GLIB_DIR) /I$(GTK_DIR) /I$(GLIB_DIR)/gmodule \
+	/I$(GTK_DIR)\gdk /I$(GTK_DIR)\gdk\win32 \
+	/I$(PCAP_DIR)\include -D_U_="" $(LOCAL_CFLAGS)
+
+OBJECTS=packet-megaco.obj 
+
+megaco.dll megaco.exp megaco.lib : packet-megaco.obj ..\plugin_api.obj
+	link -dll /out:megaco.dll packet-megaco.obj ..\plugin_api.obj \
+	$(GLIB_DIR)\glib-$(GLIB_VERSION).lib
+
+clean:
+	rm -f $(OBJECTS) megaco.dll megaco.exp megaco.lib $(PDB_FILE)
diff --git a/plugins/megaco/NEWS b/plugins/megaco/NEWS
new file mode 100644
index 0000000000..e69de29bb2
--- /dev/null
+++ b/plugins/megaco/NEWS
diff --git a/plugins/megaco/moduleinfo.h b/plugins/megaco/moduleinfo.h
new file mode 100644
index 0000000000..0bc684f1a3
--- /dev/null
+++ b/plugins/megaco/moduleinfo.h
@@ -0,0 +1,16 @@
+/* Included *after* config.h, in order to re-define these macros */
+
+#ifdef PACKAGE
+#undef PACKAGE
+#endif
+
+/* Name of package */
+#define PACKAGE "megaco"
+
+#ifdef VERSION
+#undef VERSION
+#endif
+
+/* Version number of package */
+#define VERSION "0.0.1"
+
diff --git a/plugins/megaco/packet-megaco.c b/plugins/megaco/packet-megaco.c
new file mode 100644
index 0000000000..00e98ed205
--- /dev/null
+++ b/plugins/megaco/packet-megaco.c
@@ -0,0 +1,406 @@
+/* packet-megaco.c
+ * Routines for megaco packet disassembly
+ * RFC 3015
+ *
+ * Christian Falckenberg, 2002/10/17
+ * Copyright (c) 2002 by Christian Falckenberg
+ *                       <christian.falckenberg@nortelnetworks.com>
+ *
+ * Ethereal - Network traffic analyzer
+ * By Gerald Combs <gerald@ethereal.com>
+ * Copyright 1999 Gerald Combs
+ *
+ * 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 "plugins/plugin_api.h"
+
+#include "moduleinfo.h"
+
+#include <stdio.h>
+#include <stdlib.h>
+#include <gmodule.h>
+#include <ctype.h>
+#include <time.h>
+#include <string.h>
+#include <epan/packet.h>
+#include <epan/resolv.h>
+#include "prefs.h"
+#include <epan/strutil.h>
+#include "sctpppids.h"
+
+#include "plugins/plugin_api_defs.h"
+
+#ifndef __ETHEREAL_STATIC__
+G_MODULE_EXPORT const gchar version[] = VERSION;
+#endif
+
+#define PORT_MEGACO_TXT 2944
+#define PORT_MEGACO_BIN 2945
+
+void proto_reg_handoff_megaco(void);
+
+/* Define the megaco proto */
+static int proto_megaco = -1;
+
+/* Define headers for megaco */
+static int hf_megaco_version     = -1;
+static int hf_megaco_mid         = -1;
+static int hf_megaco_transaction = -1;
+static int hf_megaco_transid     = -1;
+
+/* Define the tree for megaco */
+static int ett_megaco = -1;
+
+/*
+ * Here are the global variables associated with
+ * the various user definable characteristics of the dissection
+ *
+ * MEGACO has two kinds of message formats: text and binary
+ *
+ * global_megaco_raw_text determines whether we are going to display
+ * the raw text of the megaco message, much like the HTTP dissector does.
+ *
+ * global_megaco_dissect_tree determines whether we are going to display
+ * a detailed tree that expresses a somewhat more semantically meaningful
+ * decode.
+ */
+static int global_megaco_txt_tcp_port = PORT_MEGACO_TXT;
+static int global_megaco_txt_udp_port = PORT_MEGACO_TXT;
+static int global_megaco_bin_tcp_port = PORT_MEGACO_BIN;
+static int global_megaco_bin_udp_port = PORT_MEGACO_BIN;
+static gboolean global_megaco_raw_text = TRUE;
+static gboolean global_megaco_dissect_tree = TRUE;
+
+/*
+ * Variables to allow for proper deletion of dissector registration when
+ * the user changes port from the gui.
+ */
+static int txt_tcp_port = 0;
+static int txt_udp_port = 0;
+static int bin_tcp_port = 0;
+static int bin_udp_port = 0;
+
+/* Some basic utility functions that are specific to this dissector */
+static gint tvb_skip_wsp(tvbuff_t* tvb, gint offset, gint maxlength);
+
+/*
+ * The various functions that either dissect some
+ * subpart of MEGACO.  These aren't really proto dissectors but they
+ * are written in the same style.
+ */
+static void megaco_raw_text_add(tvbuff_t *tvb,
+				proto_tree *tree);
+
+/*
+ * dissect_megaco - The dissector for the MEGACO Protocol
+ */
+
+static void
+dissect_megaco(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree)
+{
+    gint        tvb_len, len;
+    gint        tvb_offset,tvb_current_offset,tvb_previous_offset, tokenlen;
+    proto_tree  *megaco_tree, *ti;
+    proto_item* (*my_proto_tree_add_string)(proto_tree*, int, tvbuff_t*, gint,
+					  gint, const char*);
+    guint8      word[7];
+    gint        tvb_linebegin,tvb_lineend,linelen;
+
+    /* Initialize variables */
+    tvb_len             = tvb_length(tvb);
+    megaco_tree         = NULL;
+    ti                  = NULL;
+    tvb_previous_offset = 0;
+    tvb_current_offset  = 0;
+
+    /*
+     * Check to see whether we're really dealing with MEGACO by looking
+     * for the MEGACO string.  This needs to be improved when supporting
+     * binary encodings.
+     */
+    if(!tvb_get_nstringz0(tvb,0,6,word)) return;
+    if (strncasecmp(word, "MEGACO", 6) != 0) return;
+
+    /* Display MEGACO in protocol column */
+    if (check_col(pinfo->cinfo, COL_PROTOCOL))
+	col_add_str(pinfo->cinfo, COL_PROTOCOL, "MEGACO");
+    
+    /* Display transaction in info column */
+    tvb_offset = tvb_find_guint8(tvb, 0, tvb_len, ' ');
+    tvb_offset = tvb_find_guint8(tvb, tvb_offset, tvb_len, ' ');
+    len = tvb_find_guint8(tvb, tvb_offset, tvb_len, '=') - tvb_offset;
+    
+    if (check_col(pinfo->cinfo, COL_INFO) )
+	col_add_fstr(pinfo->cinfo, COL_INFO, "%s",
+		     tvb_format_text(tvb,tvb_offset,len));
+	
+    /* Build the info tree if we've been given a root */
+    if (tree)
+    {
+	/* Create megaco subtree */
+	ti = proto_tree_add_item(tree,proto_megaco,tvb,0,0, FALSE);
+	megaco_tree = proto_item_add_subtree(ti, ett_megaco);
+
+	if(global_megaco_dissect_tree)
+	    my_proto_tree_add_string = proto_tree_add_string;
+	else 
+	    my_proto_tree_add_string = proto_tree_add_string_hidden;
+
+	/* Find version */
+
+	tvb_previous_offset = tvb_find_guint8(tvb, tvb_previous_offset,
+					 tvb_len, '/') + 1;
+	tvb_current_offset  = tvb_find_guint8(tvb, tvb_previous_offset,
+					  tvb_len, ' ');
+
+	tokenlen = tvb_current_offset - tvb_previous_offset;
+	
+	if (tree)
+	    my_proto_tree_add_string(megaco_tree, hf_megaco_version, tvb,
+				     tvb_previous_offset, tokenlen,
+				     tvb_format_text(tvb, tvb_previous_offset,
+						     tokenlen));
+    
+
+	/* Find mId (message originator identifier) */
+	tvb_previous_offset = tvb_skip_wsp(tvb, tvb_current_offset,
+					   tvb_len);
+	tvb_current_offset  = tvb_find_guint8(tvb, tvb_previous_offset,
+					      tvb_len, ' ');
+	
+	tokenlen = tvb_current_offset - tvb_previous_offset;
+
+	my_proto_tree_add_string(megaco_tree, hf_megaco_mid, tvb,
+				 tvb_previous_offset, tokenlen,
+				 tvb_format_text(tvb, tvb_previous_offset,
+						 tokenlen));
+	/* Find transaction */
+	tvb_previous_offset = tvb_skip_wsp(tvb, tvb_current_offset,
+					   tvb_len);
+	tvb_current_offset  = tvb_find_guint8(tvb, tvb_previous_offset,
+					      tvb_len, '=');
+    
+	tokenlen = tvb_current_offset - tvb_previous_offset;
+
+	my_proto_tree_add_string(megaco_tree, hf_megaco_transaction, tvb,
+				 tvb_previous_offset, tokenlen,
+				 tvb_format_text(tvb, tvb_previous_offset,
+						 tokenlen));
+	if (check_col(pinfo->cinfo, COL_INFO) )
+	    col_add_fstr(pinfo->cinfo, COL_INFO, "%s",
+			 tvb_format_text(tvb,tvb_previous_offset,tokenlen));
+	
+	/* Find transaction id */
+	tvb_previous_offset = tvb_skip_wsp(tvb, tvb_current_offset,
+					   tvb_len) + 1;
+	tvb_current_offset  = tvb_find_guint8(tvb, tvb_previous_offset,
+					      tvb_len, '{');
+	
+	tokenlen = tvb_current_offset - tvb_previous_offset;
+
+	my_proto_tree_add_string(megaco_tree, hf_megaco_transid, tvb,
+				 tvb_previous_offset, tokenlen,
+				 tvb_format_text(tvb, tvb_previous_offset,
+						 tokenlen));
+	
+	/* and finally the whole message as raw text */
+
+	if(global_megaco_raw_text){
+	    tvb_linebegin = 0;
+
+	    do {
+		tvb_find_line_end(tvb,tvb_linebegin,-1,&tvb_lineend,FALSE);
+		linelen = tvb_lineend - tvb_linebegin;
+		proto_tree_add_text(tree, tvb, tvb_linebegin, linelen,
+				    "%s", tvb_format_text(tvb,tvb_linebegin,
+							  linelen));
+		tvb_linebegin = tvb_lineend;
+	    } while ( tvb_lineend < tvb_len );
+	}
+    }
+}
+
+/* Register all the bits needed with the filtering engine */
+
+void
+proto_register_megaco(void)
+{
+    static hf_register_info hf[] = {
+	{ &hf_megaco_version,
+	  { "Version", "megaco.version", FT_STRING, BASE_DEC, NULL, 0x0,
+	    "MEGACO Version", HFILL }},
+	{ &hf_megaco_mid,
+	  { "mID", "megaco.mid", FT_STRING, BASE_DEC, NULL, 0x0,
+	    "Message Originator", HFILL }},
+	{ &hf_megaco_transaction,
+	  { "Transaction", "megaco.transaction", FT_STRING, BASE_DEC, NULL, 0x0,
+	    "Transaction type of this message", HFILL }},
+	{ &hf_megaco_transid,
+	  { "Transaction ID", "megaco.transid", FT_STRING, BASE_DEC, NULL, 0x0,
+	    "Transaction ID of this message", HFILL }},
+	/* Add more fields here */
+    };
+    static gint *ett[] = {
+	&ett_megaco,
+    };
+    module_t *megaco_module;
+
+    proto_megaco = proto_register_protocol("MEGACO",
+					   "MEGACO", "megaco");
+
+    proto_register_field_array(proto_megaco, hf, array_length(hf));
+    proto_register_subtree_array(ett, array_length(ett));
+
+    /* Register our configuration options, particularly our ports */
+
+    megaco_module = prefs_register_protocol(proto_megaco, proto_reg_handoff_megaco);
+
+    prefs_register_uint_preference(megaco_module, "tcp.txt_port",
+				   "MEGACO TXT TCP Port",
+				   "Set the TCP port for MEGACO txt messages ",
+				   10, &global_megaco_txt_tcp_port);
+
+    prefs_register_uint_preference(megaco_module, "udp.txt_port",
+				   "MEGACO TXT UDP Port",
+				   "Set the UDP port for gateway messages ",
+				   10, &global_megaco_txt_udp_port);
+
+    prefs_register_uint_preference(megaco_module, "tcp.bin_port",
+				   "MEGACO bin TCP Port",
+				   "Set the TCP port for MEGACO binary messages ",
+				   10, &global_megaco_bin_tcp_port);
+
+    prefs_register_uint_preference(megaco_module, "udp.bin_port",
+				   "MEGACO Callagent UDP Port",
+				   "Set the UDP port for callagent messages "
+				   "(if other than the default of 2727)",
+				   10, &global_megaco_bin_udp_port);
+
+
+    prefs_register_bool_preference(megaco_module, "display_raw_text",
+				   "Display raw text for MEGACO message",
+				   "Specifies that the raw text of the "
+				   "MEGACO message should be displayed "
+				   "instead of (or in addition to) the "
+				   "dissection tree",
+				   &global_megaco_raw_text);
+
+    prefs_register_bool_preference(megaco_module, "display_dissect_tree",
+				   "Display tree dissection for MEGACO message",
+				   "Specifies that the dissection tree of the "
+				   "MEGACO message should be displayed "
+				   "instead of (or in addition to) the "
+				   "raw text",
+				   &global_megaco_dissect_tree);
+}
+
+/* The registration hand-off routine */
+void
+proto_reg_handoff_megaco(void)
+{
+    static int megaco_prefs_initialized = FALSE;
+    static dissector_handle_t megaco_handle;
+
+    /*
+     * Get a handle for the SDP dissector.
+     */
+    if (!megaco_prefs_initialized) {
+	megaco_handle = create_dissector_handle(dissect_megaco, proto_megaco);
+	megaco_prefs_initialized = TRUE;
+    }
+    else {
+	dissector_delete("tcp.port", txt_tcp_port, megaco_handle);
+	dissector_delete("udp.port", txt_udp_port, megaco_handle);
+	dissector_delete("tcp.port", bin_tcp_port, megaco_handle);
+	dissector_delete("udp.port", bin_udp_port, megaco_handle);
+    }
+
+    /* Set our port number for future use */
+
+    txt_tcp_port = global_megaco_txt_tcp_port;
+    txt_udp_port = global_megaco_txt_udp_port;
+
+    bin_tcp_port = global_megaco_bin_tcp_port;
+    bin_udp_port = global_megaco_bin_udp_port;
+
+    dissector_add("tcp.port", global_megaco_txt_tcp_port, megaco_handle);
+    dissector_add("udp.port", global_megaco_txt_udp_port, megaco_handle);
+    dissector_add("tcp.port", global_megaco_bin_tcp_port, megaco_handle);
+    dissector_add("udp.port", global_megaco_bin_udp_port, megaco_handle);
+    dissector_add("sctp.ppi", H248_PAYLOAD_PROTOCOL_ID,   megaco_handle);
+}
+
+/*
+ * tvb_skip_wsp - Returns the position in tvb of the first non-whitespace
+ *                character following offset or offset + maxlength -1 whichever
+ *                is smaller.
+ *
+ * Parameters:
+ * tvb - The tvbuff in which we are skipping whitespace.
+ * offset - The offset in tvb from which we begin trying to skip whitespace.
+ * maxlength - The maximum distance from offset that we may try to skip
+ * whitespace.
+ *
+ * Returns: The position in tvb of the first non-whitespace
+ *          character following offset or offset + maxlength -1 whichever
+ *          is smaller.
+ */
+static gint tvb_skip_wsp(tvbuff_t* tvb, gint offset, gint maxlength){
+  gint counter = offset;
+  gint end,tvb_len;
+  guint8 tempchar;
+  tvb_len = tvb_length(tvb);
+  end = offset + maxlength;
+  if(end >= tvb_len){
+    end = tvb_len;
+  }
+  for(counter = offset; counter < end &&
+	((tempchar = tvb_get_guint8(tvb,counter)) == ' ' ||
+	tempchar == '\t');counter++);
+  return (counter);
+}
+
+
+/* Start the functions we need for the plugin stuff */
+
+#ifndef __ETHEREAL_STATIC__
+
+G_MODULE_EXPORT void
+plugin_reg_handoff(void){
+    proto_reg_handoff_megaco();
+}
+
+G_MODULE_EXPORT void
+plugin_init(plugin_address_table_t *pat
+#ifndef PLUGINS_NEED_ADDRESS_TABLE
+	    _U_
+#endif
+	    ){
+/* initialise the table of pointers needed in Win32 DLLs */
+    plugin_address_table_init(pat);
+/* register the new protocol, protocol fields, and subtrees */
+    if (proto_megaco == -1) { /* execute protocol initialization only once */
+	proto_register_megaco();
+    }
+}
+
+#endif
+
+/* End the functions we need for plugin stuff */