Move dissectors to epan/dissectors directory.

Also move ncp222.py, x11-fields, process-x11-fields.pl,
make-reg-dotc, and make-reg-dotc.py.

Adjust #include lines in files that include packet-*.h
files.

svn path=/trunk/; revision=11410

1 files changed, 1137 insertions, 0 deletions

diff --git a/epan/dissectors/packet-tacacs.c b/epan/dissectors/packet-tacacs.c
new file mode 100644
index 0000000000..8968beb5a5
--- /dev/null
+++ b/epan/dissectors/packet-tacacs.c
@@ -0,0 +1,1137 @@
+/* packet-tacacs.c
+ * Routines for cisco tacacs/xtacacs/tacacs+ packet dissection
+ * Copyright 2001, Paul Ionescu <paul@acorp.ro>
+ * 
+ * Full Tacacs+ parsing with decryption by
+ *   Emanuele Caratti <wiz@iol.it>
+ *
+ * $Id$
+ *
+ * Ethereal - Network traffic analyzer
+ * By Gerald Combs <gerald@ethereal.com>
+ * Copyright 1998 Gerald Combs
+ *
+ * Copied from old packet-tacacs.c
+ *
+ * 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.
+ */
+
+
+/* rfc-1492 for tacacs and xtacacs
+ * draft-grant-tacacs-02.txt for tacacs+ (tacplus)
+ */
+
+#ifdef HAVE_CONFIG_H
+# include "config.h"
+#endif
+
+#include <stdio.h>
+
+#include <string.h>
+#include <glib.h>
+#include <epan/packet.h>
+
+#include "prefs.h"
+#include "crypt-md5.h"
+#include "packet-tacacs.h"
+
+static void md5_xor( guint8 *data, char *key, int data_len, guint8 *session_id, guint8 version, guint8 seq_no );
+
+static int proto_tacacs = -1;
+static int hf_tacacs_version = -1;
+static int hf_tacacs_type = -1;
+static int hf_tacacs_nonce = -1;
+static int hf_tacacs_userlen = -1;
+static int hf_tacacs_passlen = -1;
+static int hf_tacacs_response = -1;
+static int hf_tacacs_reason = -1;
+static int hf_tacacs_result1 = -1;
+static int hf_tacacs_destaddr = -1;
+static int hf_tacacs_destport = -1;
+static int hf_tacacs_line = -1;
+static int hf_tacacs_result2 = -1;
+static int hf_tacacs_result3 = -1;
+
+static gint ett_tacacs = -1;
+
+static char *tacplus_opt_key;
+static GSList *tacplus_keys = NULL;
+
+#define VERSION_TACACS	0x00
+#define VERSION_XTACACS	0x80
+
+static const value_string tacacs_version_vals[] = {
+	{ VERSION_TACACS,  "TACACS" },
+	{ VERSION_XTACACS, "XTACACS" },
+	{ 0,               NULL }
+};
+
+#define TACACS_LOGIN		1
+#define TACACS_RESPONSE		2
+#define TACACS_CHANGE		3
+#define TACACS_FOLLOW		4
+#define TACACS_CONNECT		5
+#define TACACS_SUPERUSER	6
+#define TACACS_LOGOUT		7
+#define TACACS_RELOAD		8
+#define TACACS_SLIP_ON		9
+#define TACACS_SLIP_OFF		10
+#define TACACS_SLIP_ADDR	11
+static const value_string tacacs_type_vals[] = {
+	{ TACACS_LOGIN,     "Login" },
+	{ TACACS_RESPONSE,  "Response" },
+	{ TACACS_CHANGE,    "Change" },
+	{ TACACS_FOLLOW,    "Follow" },
+	{ TACACS_CONNECT,   "Connect" },
+	{ TACACS_SUPERUSER, "Superuser" },
+	{ TACACS_LOGOUT,    "Logout" },
+	{ TACACS_RELOAD,    "Reload" },
+	{ TACACS_SLIP_ON,   "SLIP on" },
+	{ TACACS_SLIP_OFF,  "SLIP off" },
+	{ TACACS_SLIP_ADDR, "SLIP Addr" },
+	{ 0,                NULL }};
+
+static const value_string tacacs_reason_vals[] = {
+	{ 0  , "none" },
+	{ 1  , "expiring" },
+	{ 2  , "password" },
+	{ 3  , "denied" },
+	{ 4  , "quit" },
+	{ 5  , "idle" },
+	{ 6  , "drop" },
+	{ 7  , "bad" },
+	{ 0  , NULL }
+};
+
+static const value_string tacacs_resp_vals[] = {
+	{ 0  , "this is not a response" },
+	{ 1  , "accepted" },
+	{ 2  , "rejected" },
+	{ 0  , NULL }
+};
+
+#define UDP_PORT_TACACS	49
+#define TCP_PORT_TACACS	49
+
+static void
+dissect_tacacs(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree)
+{
+	proto_tree      *tacacs_tree;
+	proto_item      *ti;
+	guint8		txt_buff[255+1],version,type,userlen,passlen;
+
+	if (check_col(pinfo->cinfo, COL_PROTOCOL))
+		col_set_str(pinfo->cinfo, COL_PROTOCOL, "TACACS");
+	if (check_col(pinfo->cinfo, COL_INFO))
+		col_clear(pinfo->cinfo, COL_INFO);
+
+	version = tvb_get_guint8(tvb,0);
+	if (version != 0) {
+		if (check_col(pinfo->cinfo, COL_PROTOCOL))
+			col_set_str(pinfo->cinfo, COL_PROTOCOL, "XTACACS");
+	}
+
+	type = tvb_get_guint8(tvb,1);
+	if (check_col(pinfo->cinfo, COL_INFO))
+		col_add_str(pinfo->cinfo, COL_INFO,
+		    val_to_str(type, tacacs_type_vals, "Unknown (0x%02x)"));
+
+	if (tree)
+	{
+		ti = proto_tree_add_protocol_format(tree, proto_tacacs,
+		 tvb, 0, -1, version==0?"TACACS":"XTACACS");
+		tacacs_tree = proto_item_add_subtree(ti, ett_tacacs);
+
+		proto_tree_add_uint(tacacs_tree, hf_tacacs_version, tvb, 0, 1,
+		    version);
+		proto_tree_add_uint(tacacs_tree, hf_tacacs_type, tvb, 1, 1,
+		    type);
+		proto_tree_add_item(tacacs_tree, hf_tacacs_nonce, tvb, 2, 2,
+		    FALSE);
+
+	if (version==0)
+	    {
+	    if (type!=TACACS_RESPONSE)
+	    	{
+	    	userlen=tvb_get_guint8(tvb,4);
+		proto_tree_add_uint(tacacs_tree, hf_tacacs_userlen, tvb, 4, 1,
+		    userlen);
+	    	passlen=tvb_get_guint8(tvb,5);
+		proto_tree_add_uint(tacacs_tree, hf_tacacs_passlen, tvb, 5, 1,
+		    passlen);
+		tvb_get_nstringz0(tvb,6,userlen+1,txt_buff);
+		proto_tree_add_text(tacacs_tree, tvb, 6, userlen,         "Username: %s",txt_buff);
+		tvb_get_nstringz0(tvb,6+userlen,passlen+1,txt_buff);
+		proto_tree_add_text(tacacs_tree, tvb, 6+userlen, passlen, "Password: %s",txt_buff);
+		}
+	    else
+	    	{
+	    	proto_tree_add_item(tacacs_tree, hf_tacacs_response, tvb, 4, 1,
+	    	    FALSE);
+	    	proto_tree_add_item(tacacs_tree, hf_tacacs_reason, tvb, 5, 1,
+	    	    FALSE);
+		}
+	    }
+	else
+	    {
+	    userlen=tvb_get_guint8(tvb,4);
+	    proto_tree_add_uint(tacacs_tree, hf_tacacs_userlen, tvb, 4, 1,
+		userlen);
+	    passlen=tvb_get_guint8(tvb,5);
+	    proto_tree_add_uint(tacacs_tree, hf_tacacs_passlen, tvb, 5, 1,
+		passlen);
+	    proto_tree_add_item(tacacs_tree, hf_tacacs_response, tvb, 6, 1,
+		FALSE);
+	    proto_tree_add_item(tacacs_tree, hf_tacacs_reason, tvb, 7, 1,
+		FALSE);
+	    proto_tree_add_item(tacacs_tree, hf_tacacs_result1, tvb, 8, 4,
+		FALSE);
+	    proto_tree_add_item(tacacs_tree, hf_tacacs_destaddr, tvb, 12, 4,
+		FALSE);
+	    proto_tree_add_item(tacacs_tree, hf_tacacs_destport, tvb, 16, 2,
+		FALSE);
+	    proto_tree_add_item(tacacs_tree, hf_tacacs_line, tvb, 18, 2,
+		FALSE);
+	    proto_tree_add_item(tacacs_tree, hf_tacacs_result2, tvb, 20, 4,
+		FALSE);
+	    proto_tree_add_item(tacacs_tree, hf_tacacs_result3, tvb, 24, 2,
+		FALSE);
+	    if (type!=TACACS_RESPONSE)
+	    	{
+	    	tvb_get_nstringz0(tvb,26,userlen+1,txt_buff);
+	    	proto_tree_add_text(tacacs_tree, tvb, 26, userlen,  "Username: %s",txt_buff);
+	    	tvb_get_nstringz0(tvb,26+userlen,passlen+1,txt_buff);
+	    	proto_tree_add_text(tacacs_tree, tvb, 26+userlen, passlen, "Password; %s",txt_buff);
+	    	}
+	    }
+	}
+}
+
+void
+proto_register_tacacs(void)
+{
+	static hf_register_info hf[] = {
+	  { &hf_tacacs_version,
+	    { "Version",           "tacacs.version",
+	      FT_UINT8, BASE_HEX, VALS(tacacs_version_vals), 0x0,
+	      "Version", HFILL }},
+	  { &hf_tacacs_type,
+	    { "Type",              "tacacs.type",
+	      FT_UINT8, BASE_DEC, VALS(tacacs_type_vals), 0x0,
+	      "Type", HFILL }},
+	  { &hf_tacacs_nonce,
+	    { "Nonce",             "tacacs.nonce",
+	      FT_UINT16, BASE_HEX, NULL, 0x0,
+	      "Nonce", HFILL }},
+	  { &hf_tacacs_userlen,
+	    { "Username length",   "tacacs.userlen",
+	      FT_UINT8, BASE_DEC, NULL, 0x0,
+	      "Username length", HFILL }},
+	  { &hf_tacacs_passlen,
+	    { "Password length",   "tacacs.passlen",
+	      FT_UINT8, BASE_DEC, NULL, 0x0,
+	      "Password length", HFILL }},
+	  { &hf_tacacs_response,
+	    { "Response",          "tacacs.response",
+	      FT_UINT8, BASE_DEC, VALS(tacacs_resp_vals), 0x0,
+	      "Response", HFILL }},
+	  { &hf_tacacs_reason,
+	    { "Reason",            "tacacs.reason",
+	      FT_UINT8, BASE_DEC, VALS(tacacs_reason_vals), 0x0,
+	      "Reason", HFILL }},
+	  { &hf_tacacs_result1,
+	    { "Result 1",          "tacacs.result1",
+	      FT_UINT32, BASE_HEX, NULL, 0x0,
+	      "Result 1", HFILL }},
+	  { &hf_tacacs_destaddr,
+	    { "Destination address", "tacacs.destaddr",
+	      FT_IPv4, BASE_NONE, NULL, 0x0,
+	      "Destination address", HFILL }},
+	  { &hf_tacacs_destport,
+	    { "Destination port",  "tacacs.destport",
+	      FT_UINT16, BASE_DEC, NULL, 0x0,
+	      "Destination port", HFILL }},
+	  { &hf_tacacs_line,
+	    { "Line",              "tacacs.line",
+	      FT_UINT16, BASE_DEC, NULL, 0x0,
+	      "Line", HFILL }},
+	  { &hf_tacacs_result2,
+	    { "Result 2",          "tacacs.result2",
+	      FT_UINT32, BASE_HEX, NULL, 0x0,
+	      "Result 2", HFILL }},
+	  { &hf_tacacs_result3,
+	    { "Result 3",          "tacacs.result3",
+	      FT_UINT16, BASE_HEX, NULL, 0x0,
+	      "Result 3", HFILL }},
+	};
+
+	static gint *ett[] = {
+		&ett_tacacs,
+	};
+	proto_tacacs = proto_register_protocol("TACACS", "TACACS", "tacacs");
+	proto_register_field_array(proto_tacacs, hf, array_length(hf));
+	proto_register_subtree_array(ett, array_length(ett));
+}
+
+void
+proto_reg_handoff_tacacs(void)
+{
+	dissector_handle_t tacacs_handle;
+
+	tacacs_handle = create_dissector_handle(dissect_tacacs, proto_tacacs);
+	dissector_add("udp.port", UDP_PORT_TACACS, tacacs_handle);
+}
+
+static int proto_tacplus = -1;
+static int hf_tacplus_response = -1;
+static int hf_tacplus_request = -1;
+static int hf_tacplus_majvers = -1;
+static int hf_tacplus_minvers = -1;
+static int hf_tacplus_type = -1;
+static int hf_tacplus_seqno = -1;
+static int hf_tacplus_flags = -1;
+static int hf_tacplus_flags_payload_type = -1;
+static int hf_tacplus_flags_connection_type = -1;
+static int hf_tacplus_acct_flags = -1;
+static int hf_tacplus_session_id = -1;
+static int hf_tacplus_packet_len = -1;
+
+static gint ett_tacplus = -1;
+static gint ett_tacplus_body = -1;
+static gint ett_tacplus_body_chap = -1;
+static gint ett_tacplus_flags = -1;
+static gint ett_tacplus_acct_flags = -1;
+
+typedef struct _tacplus_key_entry {
+	address  *s; /* Server address */
+	address  *c; /* client address */
+	char	*k; /* Key */
+} tacplus_key_entry;
+
+static gint 
+tacplus_decrypted_tvb_setup( tvbuff_t *tvb, tvbuff_t **dst_tvb, packet_info *pinfo, guint32 len, guint8 version, char *key )
+{
+	guint8	*buff;
+	guint8 session_id[4];
+
+	/* TODO Check the possibility to use pinfo->decrypted_data */
+/* session_id is in NETWORK Byte Order, and is used as byte array in the md5_xor */
+
+	tvb_memcpy(tvb, (guint8*)session_id, 4,4); 
+
+	buff = tvb_memdup(tvb, TAC_PLUS_HDR_SIZE, len);
+
+
+	md5_xor( buff, key, len, session_id,version, tvb_get_guint8(tvb,2) );
+
+	/* Allocate a new tvbuff, referring to the decrypted data. */
+	*dst_tvb = tvb_new_real_data( buff, len, len );
+
+	/* Arrange that the allocated packet data copy be freed when the
+	   tvbuff is freed. */
+	tvb_set_free_cb( *dst_tvb, g_free );
+
+	/* Add the tvbuff to the list of tvbuffs to which the tvbuff we
+	   were handed refers, so it'll get cleaned up when that tvbuff
+	   is cleaned up. */
+	tvb_set_child_real_data_tvbuff( tvb, *dst_tvb );
+
+	/* Add the decrypted data to the data source list. */
+	add_new_data_source(pinfo, *dst_tvb, "TACACS+ Decrypted");
+
+	return 0;
+}
+static void
+dissect_tacplus_args_list( tvbuff_t *tvb, proto_tree *tree, int data_off, int len_off, int arg_cnt )
+{
+	int i;
+	guint8	buff[257];
+	for(i=0;i<arg_cnt;i++){
+		int len=tvb_get_guint8(tvb,len_off+i);
+		proto_tree_add_text( tree, tvb, len_off+i, 1, "Arg[%d] length: %d", i, len );
+		tvb_get_nstringz0(tvb, data_off, len+1, buff);
+		proto_tree_add_text( tree, tvb, data_off, len, "Arg[%d] value: %s", i, buff );
+		data_off+=len;
+	}
+}
+
+
+static int
+proto_tree_add_tacplus_common_fields( tvbuff_t *tvb, proto_tree *tree,  int offset, int var_off )
+{
+	int val;
+	guint8 buff[257];
+	/* priv_lvl */
+	proto_tree_add_text( tree, tvb, offset, 1,
+			"Privilege Level: %d", tvb_get_guint8(tvb,offset) );
+	offset++;
+
+	/* authen_type */
+	val=tvb_get_guint8(tvb,offset);
+	proto_tree_add_text( tree, tvb, offset, 1,
+			"Authentication type: %s",
+			val_to_str( val, tacplus_authen_type_vals, "Unknown Packet" ) );
+	offset++;
+
+	/* service */
+	val=tvb_get_guint8(tvb,offset);
+	proto_tree_add_text( tree, tvb, offset, 1,
+			"Service: %s",
+			val_to_str( val, tacplus_authen_service_vals, "Unknown Packet" ) );
+	offset++;
+
+	/* user_len && user */
+	val=tvb_get_guint8(tvb,offset);
+	proto_tree_add_text( tree, tvb, offset, 1, "User len: %d", val );
+	if( val ){
+		tvb_get_nstringz0(tvb, var_off, val+1, buff);
+		proto_tree_add_text( tree, tvb, var_off, val, "User: %s", buff );
+		var_off+=val;
+	}
+	offset++;
+
+
+	/* port_len &&  port */
+	val=tvb_get_guint8(tvb,offset);
+	proto_tree_add_text( tree, tvb, offset, 1, "Port len: %d", val );
+	if( val ){
+		tvb_get_nstringz0(tvb, var_off, val+1, buff);
+		proto_tree_add_text( tree, tvb, var_off, val, "Port: %s", buff );
+		var_off+=val;
+	}
+	offset++;
+
+	/* rem_addr_len && rem_addr */
+	val=tvb_get_guint8(tvb,offset);
+	proto_tree_add_text( tree, tvb, offset, 1, "Remaddr len: %d", val );
+	if( val ){
+		tvb_get_nstringz0(tvb, var_off, val+1, buff);
+		proto_tree_add_text( tree, tvb, var_off, val, "Remote Address: %s", buff );
+		var_off+=val;
+	}
+	return var_off;
+}
+
+static void
+dissect_tacplus_body_authen_req_login( tvbuff_t* tvb, proto_tree *tree, int var_off )
+{
+	guint8 buff[257];
+	guint8 val;
+	val=tvb_get_guint8( tvb, AUTHEN_S_DATA_LEN_OFF );
+
+	switch ( tvb_get_guint8(tvb, AUTHEN_S_AUTHEN_TYPE_OFF ) ) { /* authen_type */
+
+		case TAC_PLUS_AUTHEN_TYPE_ASCII:
+			proto_tree_add_text( tree, tvb, AUTHEN_S_DATA_LEN_OFF, 1, "Data: %d (not used)", val );
+			if( val )
+				proto_tree_add_text( tree, tvb, var_off, val, "Data" );
+			break;
+
+		case TAC_PLUS_AUTHEN_TYPE_PAP:
+			proto_tree_add_text( tree, tvb, AUTHEN_S_DATA_LEN_OFF, 1, "Password Length %d", val );
+			if( val ) {
+				tvb_get_nstringz0( tvb, var_off, val+1, buff );
+				proto_tree_add_text( tree, tvb, var_off, val, "Password: %s", buff );
+			}
+			break;
+
+		case TAC_PLUS_AUTHEN_TYPE_CHAP:
+			proto_tree_add_text( tree, tvb, AUTHEN_S_DATA_LEN_OFF, 1, "CHAP Data Length %d", val );
+			if( val ) {
+				proto_item	*pi;
+				proto_tree  *pt;
+				guint8 chal_len=val-(1+16); /* Response field alwayes 16 octets */
+				pi = proto_tree_add_text(tree, tvb, var_off, val, "CHAP Data" );
+				pt = proto_item_add_subtree( pi, ett_tacplus_body_chap );
+				val= tvb_get_guint8( tvb, var_off );
+				proto_tree_add_text( pt, tvb, var_off, 1, "ID: %d", val );
+				var_off++;
+				tvb_get_nstringz0( tvb, var_off, chal_len+1, buff );
+				proto_tree_add_text( pt, tvb, var_off, chal_len, "Challenge: %s", buff );
+				var_off+=chal_len;
+				tvb_get_nstringz0( tvb, var_off, 16+1, buff );
+				proto_tree_add_text( pt, tvb, var_off, 16 , "Response: %s", buff );
+			}
+			break;
+		case TAC_PLUS_AUTHEN_TYPE_MSCHAP:
+			proto_tree_add_text( tree, tvb, AUTHEN_S_DATA_LEN_OFF, 1, "MSCHAP Data Length %d", val );
+			if( val ) {
+				proto_item	*pi;
+				proto_tree  *pt;
+				guint8 chal_len=val-(1+49);  /* Response field alwayes 49 octets */
+				pi = proto_tree_add_text(tree, tvb, var_off, val, "MSCHAP Data" );
+				pt = proto_item_add_subtree( pi, ett_tacplus_body_chap );
+				val= tvb_get_guint8( tvb, var_off );
+				proto_tree_add_text( pt, tvb, var_off, 1, "ID: %d", val );
+				var_off++;
+				tvb_get_nstringz0( tvb, var_off, chal_len+1, buff );
+				proto_tree_add_text( pt, tvb, var_off, chal_len, "Challenge: %s", buff );
+				var_off+=chal_len;
+				tvb_get_nstringz0( tvb, var_off, 49+1, buff );
+				proto_tree_add_text( pt, tvb, var_off, 49 , "Response: %s", buff );
+			}
+			break;
+		case TAC_PLUS_AUTHEN_TYPE_ARAP:
+			proto_tree_add_text( tree, tvb, AUTHEN_S_DATA_LEN_OFF, 1, "ARAP Data Length %d", val );
+			if( val ) {
+				proto_item	*pi;
+				proto_tree  *pt;
+				pi = proto_tree_add_text(tree, tvb, var_off, val, "ARAP Data" );
+				pt = proto_item_add_subtree( pi, ett_tacplus_body_chap );
+
+				tvb_get_nstringz0( tvb, var_off, 8+1, buff );
+				proto_tree_add_text( pt, tvb, var_off, 8, "Nas Challenge: %s", buff );
+				var_off+=8;
+				tvb_get_nstringz0( tvb, var_off, 8+1, buff );
+				proto_tree_add_text( pt, tvb, var_off, 8, "Remote Challenge: %s", buff );
+				var_off+=8;
+				tvb_get_nstringz0( tvb, var_off, 8+1, buff );
+				proto_tree_add_text( pt, tvb, var_off, 8, "Remote Response: %s", buff );
+				var_off+=8;
+			}
+			break;
+
+		default: /* Should not be reached */
+			proto_tree_add_text( tree, tvb, AUTHEN_S_DATA_LEN_OFF, 1, "Data: %d", val );
+			if( val ){
+				proto_tree_add_text( tree, tvb, var_off, val, "Data" );
+			}
+	}
+}
+
+static void
+dissect_tacplus_body_authen_req( tvbuff_t* tvb, proto_tree *tree )
+{
+	guint8 val;
+	int var_off=AUTHEN_S_VARDATA_OFF;
+
+	/* Action */
+	val=tvb_get_guint8( tvb, AUTHEN_S_ACTION_OFF );
+	proto_tree_add_text( tree, tvb,
+			AUTHEN_S_ACTION_OFF, 1, 
+			"Action: %s", 
+			val_to_str( val, tacplus_authen_action_vals, "Unknown Packet" ) );
+
+	var_off=proto_tree_add_tacplus_common_fields( tvb, tree , AUTHEN_S_PRIV_LVL_OFF, AUTHEN_S_VARDATA_OFF );
+
+	switch( val ) {
+		case TAC_PLUS_AUTHEN_LOGIN:
+			dissect_tacplus_body_authen_req_login( tvb, tree, var_off );
+			break;
+		case TAC_PLUS_AUTHEN_SENDAUTH:
+			break;
+	}
+}
+
+static void
+dissect_tacplus_body_authen_req_cont( tvbuff_t *tvb, proto_tree *tree )
+{
+	int val;
+	int var_off=AUTHEN_C_VARDATA_OFF;
+	guint8 *buff=NULL;
+
+	val=tvb_get_guint8( tvb, AUTHEN_C_FLAGS_OFF );
+	proto_tree_add_text( tree, tvb,
+			AUTHEN_R_FLAGS_OFF, 1, "Flags: 0x%02x %s",
+			val,
+			(val&TAC_PLUS_CONTINUE_FLAG_ABORT?"(Abort)":"") );
+
+
+	val=tvb_get_ntohs( tvb, AUTHEN_C_USER_LEN_OFF ); 
+	proto_tree_add_text( tree, tvb, AUTHEN_C_USER_LEN_OFF, 2 , "User length: %d", val );
+	if( val ){
+		buff=tvb_get_string( tvb, var_off, val );
+		proto_tree_add_text( tree, tvb, var_off, val, "User: %s", buff );
+		var_off+=val;
+		g_free(buff);
+	}
+
+	val=tvb_get_ntohs( tvb, AUTHEN_C_DATA_LEN_OFF ); 
+	proto_tree_add_text( tree, tvb, AUTHEN_C_DATA_LEN_OFF, 2 ,
+			"Data length: %d", val );
+	if( val ){
+		proto_tree_add_text( tree, tvb, var_off, val, "Data" );
+	}
+
+}
+
+/* Server REPLY */
+static void
+dissect_tacplus_body_authen_rep( tvbuff_t *tvb, proto_tree *tree )
+{
+	int val;
+	int var_off=AUTHEN_R_VARDATA_OFF;
+	guint8 *buff=NULL;
+
+	val=tvb_get_guint8( tvb, AUTHEN_R_STATUS_OFF );
+	proto_tree_add_text(tree, tvb,
+			AUTHEN_R_STATUS_OFF, 1, "Status: 0x%01x (%s)", val,
+			val_to_str( val, tacplus_reply_status_vals, "Unknown Packet" )  );
+
+	val=tvb_get_guint8( tvb, AUTHEN_R_FLAGS_OFF );
+	proto_tree_add_text(tree, tvb,
+			AUTHEN_R_FLAGS_OFF, 1, "Flags: 0x%02x %s",
+			val, (val&TAC_PLUS_REPLY_FLAG_NOECHO?"(NoEcho)":"") );
+	
+
+	val=tvb_get_ntohs(tvb, AUTHEN_R_SRV_MSG_LEN_OFF );
+	proto_tree_add_text( tree, tvb, AUTHEN_R_SRV_MSG_LEN_OFF, 2 ,
+				"Server message length: %d", val );
+	if( val ) {
+		buff=tvb_get_string(tvb, var_off, val );
+		proto_tree_add_text(tree, tvb, var_off, val, "Server message: %s", buff );
+		var_off+=val;
+		g_free(buff);
+	}
+
+	val=tvb_get_ntohs(tvb, AUTHEN_R_DATA_LEN_OFF );
+	proto_tree_add_text( tree, tvb, AUTHEN_R_DATA_LEN_OFF, 2 ,
+				"Data length: %d", val );
+	if( val ){
+		proto_tree_add_text(tree, tvb, var_off, val, "Data" );
+	}
+}
+
+static void
+dissect_tacplus_body_author_req( tvbuff_t* tvb, proto_tree *tree )
+{
+	int val;
+	int var_off;
+
+	val=tvb_get_guint8( tvb, AUTHOR_Q_AUTH_METH_OFF ) ;
+	proto_tree_add_text( tree, tvb, AUTHOR_Q_AUTH_METH_OFF, 1, 
+			"Auth Method: %s", val_to_str( val, tacplus_authen_method, "Unknown Authen Method" ) );
+
+	val=tvb_get_guint8( tvb, AUTHOR_Q_ARGC_OFF );
+	var_off=proto_tree_add_tacplus_common_fields( tvb, tree ,
+			AUTHOR_Q_PRIV_LVL_OFF,
+			AUTHOR_Q_VARDATA_OFF + val );
+
+	proto_tree_add_text( tree, tvb, AUTHOR_Q_ARGC_OFF, 1, "Arg count: %d", val );
+	
+/* var_off points after rem_addr */
+
+	dissect_tacplus_args_list( tvb, tree, var_off, AUTHOR_Q_VARDATA_OFF, val );
+}
+
+static void
+dissect_tacplus_body_author_rep( tvbuff_t* tvb, proto_tree *tree )
+{
+	int offset=AUTHOR_R_VARDATA_OFF;
+	int val=tvb_get_guint8( tvb, AUTHOR_R_STATUS_OFF	) ;
+
+
+	proto_tree_add_text( tree, tvb, AUTHOR_R_STATUS_OFF	, 1, 
+			"Auth Status: 0x%01x (%s)", val,
+			val_to_str( val, tacplus_author_status, "Unknown Authorization Status" ));
+
+	val=tvb_get_ntohs( tvb, AUTHOR_R_SRV_MSG_LEN_OFF );
+	offset+=val;
+	proto_tree_add_text( tree, tvb, AUTHOR_R_SRV_MSG_LEN_OFF, 2, "Server Msg length: %d", val );
+
+	val=tvb_get_ntohs( tvb, AUTHOR_R_DATA_LEN_OFF );
+	offset+=val;
+	proto_tree_add_text( tree, tvb, AUTHOR_R_DATA_LEN_OFF, 2, "Data length: %d", val );
+
+	val=tvb_get_guint8( tvb, AUTHOR_R_ARGC_OFF);
+	offset+=val;
+	proto_tree_add_text( tree, tvb, AUTHOR_R_ARGC_OFF, 1, "Arg count: %d", val );
+
+	dissect_tacplus_args_list( tvb, tree, offset, AUTHOR_R_VARDATA_OFF, val );
+}
+
+static void
+dissect_tacplus_body_acct_req( tvbuff_t* tvb, proto_tree *tree )
+{
+	int val, var_off;
+
+	proto_item *tf;
+	proto_tree *flags_tree;
+
+	val=tvb_get_guint8( tvb, ACCT_Q_FLAGS_OFF ); 
+	tf = proto_tree_add_uint( tree, hf_tacplus_acct_flags, tvb, ACCT_Q_FLAGS_OFF, 1, val );
+
+	flags_tree = proto_item_add_subtree( tf, ett_tacplus_acct_flags );
+	proto_tree_add_text( flags_tree, tvb, ACCT_Q_FLAGS_OFF, 1, "%s",
+			decode_boolean_bitfield( val, TAC_PLUS_ACCT_FLAG_MORE, 8,
+				"More: Set", "More: Not set" ) );
+	proto_tree_add_text( flags_tree, tvb, ACCT_Q_FLAGS_OFF, 1, "%s",
+			decode_boolean_bitfield( val, TAC_PLUS_ACCT_FLAG_START, 8,
+				"Start: Set", "Start: Not set" ) );
+	proto_tree_add_text( flags_tree, tvb, ACCT_Q_FLAGS_OFF, 1, "%s",
+			decode_boolean_bitfield( val, TAC_PLUS_ACCT_FLAG_STOP, 8,
+				"Stop: Set", "Stop: Not set" ) );
+	proto_tree_add_text( flags_tree, tvb, ACCT_Q_FLAGS_OFF, 1, "%s",
+			decode_boolean_bitfield( val, TAC_PLUS_ACCT_FLAG_WATCHDOG, 8,
+				"Watchdog: Set", "Watchdog: Not set" ) );
+
+	val=tvb_get_guint8( tvb, ACCT_Q_METHOD_OFF );
+	proto_tree_add_text( tree, tvb, ACCT_Q_METHOD_OFF, 1, 
+			"Authen Method: 0x%01x (%s)",  
+			val, val_to_str( val, tacplus_authen_method, "Unknown Authen Method" ) );
+
+	val=tvb_get_guint8( tvb, ACCT_Q_ARG_CNT_OFF );
+
+	/* authen_type */
+	var_off=proto_tree_add_tacplus_common_fields( tvb, tree ,
+			ACCT_Q_PRIV_LVL_OFF,
+			ACCT_Q_VARDATA_OFF+val
+			);
+
+	proto_tree_add_text( tree, tvb, ACCT_Q_ARG_CNT_OFF, 1,
+			"Arg Cnt: %d", val  );
+
+	dissect_tacplus_args_list( tvb, tree, var_off, ACCT_Q_VARDATA_OFF, val );
+
+
+}
+
+static void
+dissect_tacplus_body_acct_rep( tvbuff_t* tvb, proto_tree *tree )
+{
+	int val, var_off=ACCT_Q_VARDATA_OFF;
+
+	guint8 *buff=NULL;
+
+	/* Status */
+	val=tvb_get_guint8( tvb, ACCT_R_STATUS_OFF );
+	proto_tree_add_text( tree, tvb, ACCT_R_STATUS_OFF, 1, "Status: 0x%02x (%s)", val,
+				val_to_str( val, tacplus_acct_status, "Bogus status..") );
+
+	/* Server Message */
+	val=tvb_get_ntohs( tvb, ACCT_R_SRV_MSG_LEN_OFF );
+	proto_tree_add_text( tree, tvb, ACCT_R_SRV_MSG_LEN_OFF, 2 ,
+				"Server message length: %d", val );
+	if( val ) {
+		buff=tvb_get_string( tvb, var_off, val );
+		proto_tree_add_text( tree, tvb, var_off,
+				val, "Server message: %s", buff );
+		var_off+=val;
+		g_free(buff);
+	}
+
+	/*  Data */
+	val=tvb_get_ntohs( tvb, ACCT_R_DATA_LEN_OFF );
+	proto_tree_add_text( tree, tvb, ACCT_R_DATA_LEN_OFF, 2 ,
+				"Data length: %d", val );
+	if( val ) {
+		buff= tvb_get_string( tvb, var_off, val );
+		proto_tree_add_text( tree, tvb, var_off,
+				val, "Data: %s", buff );
+		g_free(buff);
+	}
+}
+
+
+
+static void
+dissect_tacplus_body(tvbuff_t * hdr_tvb, tvbuff_t * tvb, proto_tree * tree )
+{
+	int type = tvb_get_guint8( hdr_tvb, H_TYPE_OFF );
+	int seq_no = tvb_get_guint8( hdr_tvb, H_SEQ_NO_OFF );
+
+	switch (type) {
+	  case TAC_PLUS_AUTHEN:
+		if (  seq_no & 0x01) {
+			if ( seq_no == 1 )
+				dissect_tacplus_body_authen_req( tvb, tree );
+			else
+				dissect_tacplus_body_authen_req_cont( tvb, tree );
+		} else {
+			dissect_tacplus_body_authen_rep( tvb, tree );
+		}
+		return;
+		break;
+	  case TAC_PLUS_AUTHOR:
+		if ( seq_no & 0x01)
+			dissect_tacplus_body_author_req( tvb, tree );
+		else 
+			dissect_tacplus_body_author_rep( tvb, tree );
+		return;
+		break;
+	  case TAC_PLUS_ACCT:
+		if ( seq_no & 0x01)
+			dissect_tacplus_body_acct_req( tvb, tree ); 
+		else
+			dissect_tacplus_body_acct_rep( tvb, tree );
+		return;
+		break;
+	}
+	proto_tree_add_text( tree, tvb, 0, tvb_length( tvb ), "Bogus..");
+}
+
+#ifdef DEB_TACPLUS
+static void
+tacplus_print_key_entry( gpointer data, gpointer user_data )
+{
+	tacplus_key_entry *tacplus_data=(tacplus_key_entry *)data;
+	if( user_data ) {
+		printf("%s:%s=%s\n", address_to_str( tacplus_data->s ),
+				address_to_str( tacplus_data->c ), tacplus_data->k );
+	} else {
+		printf("%s:%s\n", address_to_str( tacplus_data->s ),
+				address_to_str( tacplus_data->c ) );
+	}
+}
+#endif
+static int
+cmp_conv_address( gconstpointer p1, gconstpointer p2 )
+{
+	tacplus_key_entry *a1=(tacplus_key_entry*)p1;
+	tacplus_key_entry *a2=(tacplus_key_entry*)p2;
+	gint32	ret;
+	/*
+	printf("p1=>");
+	tacplus_print_key_entry( p1, NULL );
+	printf("p2=>");
+	tacplus_print_key_entry( p2, NULL );
+	*/
+	ret=CMP_ADDRESS( a1->s, a2->s );
+	if( !ret ) {
+		ret=CMP_ADDRESS( a1->c, a2->c );
+		/*
+		if(ret)
+			printf("No Client found!"); */
+	} else {
+		/* printf("No Server found!"); */
+	}
+	return ret;
+}
+
+static char*
+find_key( address *srv, address *cln )
+{
+	tacplus_key_entry data;
+	GSList *match;
+
+	data.s=srv;
+	data.c=cln;
+/*	printf("Looking for: ");
+	tacplus_print_key_entry( (gconstpointer)&data, NULL ); */
+	match=g_slist_find_custom( tacplus_keys, (gpointer)&data, cmp_conv_address );
+/*	printf("Finished (%p)\n", match);  */
+	if( match ) 
+		return ((tacplus_key_entry*)match->data)->k;
+
+	return (tacplus_keys?NULL:tacplus_opt_key);
+}
+#define AF_INET 2
+int inet_pton(int , const char*, void*);
+
+static void
+mkipv4_address( address **addr, char *str_addr )
+{
+	*addr=g_malloc( sizeof(address) );
+	(*addr)->type=AT_IPv4;
+	(*addr)->len=4;
+	(*addr)->data=g_malloc( 4 );
+	inet_pton( AF_INET, (const char*)str_addr, (void*)(*addr)->data );
+}
+static void
+parse_tuple( char *key_from_option )
+{
+	char *client,*key;
+	tacplus_key_entry *tacplus_data=g_malloc( sizeof(tacplus_key_entry) );
+	/*
+	printf("keys: %s\n", key_from_option );
+	*/
+	client=strchr(key_from_option,'/');
+	if(!client)
+		return;
+	*client++='\0';
+	key=strchr(client,'=');
+	if(!key)
+		return;
+	*key++='\0';
+	/*
+	printf("%s %s => %s\n", key_from_option, client, key );
+	*/
+	mkipv4_address( &tacplus_data->s, key_from_option );
+	mkipv4_address( &tacplus_data->c, client );
+	tacplus_data->k=strdup( key );
+	tacplus_keys = g_slist_prepend( tacplus_keys, tacplus_data );
+}
+
+static
+void
+free_tacplus_keys( gpointer data, gpointer user_data _U_ )
+{
+	g_free( ((tacplus_key_entry *)data)->k );
+}
+
+static 
+void
+parse_tacplus_keys( char *keys_from_option )
+{
+	char *s1,*s;
+
+	/* Drop old keys */
+	if( tacplus_keys ) {
+		g_slist_foreach( tacplus_keys, free_tacplus_keys, NULL );
+		g_slist_free( tacplus_keys );
+		tacplus_keys=NULL;
+	}
+
+	if( !strchr( keys_from_option, '/' ) ){
+		/* option not in client/server=key format */
+		return ;
+	}
+	s=strdup(keys_from_option);
+	s1=s;
+	keys_from_option = s;
+	while(keys_from_option){
+		if( (s=strchr( keys_from_option, ' ' )) != NULL )
+			*s++='\0';
+		parse_tuple( keys_from_option );
+		keys_from_option=s;
+	}
+	g_free( s1 );
+#ifdef DEB_TACPLUS
+	g_slist_foreach( tacplus_keys, tacplus_print_key_entry, GINT_TO_POINTER(1) );
+#endif
+}
+
+static void
+dissect_tacplus(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree)
+{
+	tvbuff_t	*new_tvb=NULL;
+	proto_tree      *tacplus_tree;
+	proto_item      *ti;
+	guint8		version,flags;
+	proto_tree      *flags_tree;
+	proto_item      *tf;
+	proto_item	*tmp_pi;
+	guint32		len;
+	gboolean	request=( pinfo->destport == TCP_PORT_TACACS );
+	char		*key=NULL;
+
+	if( request ) {
+		key=find_key( &pinfo->dst, &pinfo->src );
+	} else {
+		key=find_key(  &pinfo->src, &pinfo->dst );
+	}
+	if (check_col(pinfo->cinfo, COL_PROTOCOL))
+		col_set_str(pinfo->cinfo, COL_PROTOCOL, "TACACS+");
+
+	if (check_col(pinfo->cinfo, COL_INFO))
+	{
+		int type = tvb_get_guint8(tvb,1);
+		col_add_fstr( pinfo->cinfo, COL_INFO, "%s: %s", 
+				request ? "Q" : "R",
+				val_to_str(type, tacplus_type_vals, "Unknown (0x%02x)"));
+	}
+
+	if (tree)
+	{
+		ti = proto_tree_add_protocol_format(tree, proto_tacplus,
+		 tvb, 0, -1, "TACACS+");
+
+		tacplus_tree = proto_item_add_subtree(ti, ett_tacplus);
+		if (pinfo->match_port == pinfo->destport)
+		{
+			proto_tree_add_boolean_hidden(tacplus_tree,
+			    hf_tacplus_request, tvb, 0, 0, TRUE);
+		}
+		else
+		{
+			proto_tree_add_boolean_hidden(tacplus_tree,
+			    hf_tacplus_response, tvb, 0, 0, TRUE);
+		}
+		version = tvb_get_guint8(tvb,0);
+		proto_tree_add_uint_format(tacplus_tree, hf_tacplus_majvers, tvb, 0, 1,
+		    version,
+		    "Major version: %s",
+		    (version&0xf0)==0xc0?"TACACS+":"Unknown Version");
+		proto_tree_add_uint(tacplus_tree, hf_tacplus_minvers, tvb, 0, 1,
+		    version&0xf);
+		proto_tree_add_item(tacplus_tree, hf_tacplus_type, tvb, 1, 1,
+		    FALSE);
+		proto_tree_add_item(tacplus_tree, hf_tacplus_seqno, tvb, 2, 1,
+		    FALSE);
+		flags = tvb_get_guint8(tvb,3);
+		tf = proto_tree_add_uint_format(tacplus_tree, hf_tacplus_flags,
+		    tvb, 3, 1, flags,
+		    "Flags: 0x%02x (%s payload, %s)",
+			flags,
+		    (flags&FLAGS_UNENCRYPTED) ? "Unencrypted" :
+						"Encrypted",
+		    (flags&FLAGS_SINGLE) ? "Single connection" :
+					   "Multiple Connections" );
+		flags_tree = proto_item_add_subtree(tf, ett_tacplus_flags);
+		proto_tree_add_boolean(flags_tree, hf_tacplus_flags_payload_type,
+		    tvb, 3, 1, flags);
+		proto_tree_add_boolean(flags_tree, hf_tacplus_flags_connection_type,
+		    tvb, 3, 1, flags);
+		proto_tree_add_item(tacplus_tree, hf_tacplus_session_id, tvb, 4, 4,
+		    FALSE);
+		len = tvb_get_ntohl(tvb,8);
+		proto_tree_add_uint(tacplus_tree, hf_tacplus_packet_len, tvb, 8, 4,
+		    len);
+
+		tmp_pi = proto_tree_add_text(tacplus_tree, tvb, TAC_PLUS_HDR_SIZE, len, "%s%s",
+					((flags&FLAGS_UNENCRYPTED)?"":"Encrypted "), request?"Request":"Reply" );
+
+		if( flags&FLAGS_UNENCRYPTED ) {
+			new_tvb = tvb_new_subset( tvb, TAC_PLUS_HDR_SIZE, len, len );
+		}  else {
+			new_tvb=NULL;
+			if( key && *key ){
+				tacplus_decrypted_tvb_setup( tvb, &new_tvb, pinfo, len, version, key );
+			}
+		}
+		if( new_tvb ) {
+			/* Check to see if I've a decrypted tacacs packet */
+			if( !(flags&FLAGS_UNENCRYPTED) ){ 	
+				tmp_pi = proto_tree_add_text(tacplus_tree, new_tvb, 0, len, "Decrypted %s",
+							request?"Request":"Reply" );
+			}
+			dissect_tacplus_body( tvb, new_tvb, proto_item_add_subtree( tmp_pi, ett_tacplus_body ));
+		}
+	}
+}
+
+void
+tacplus_pref_cb(void)
+{
+	parse_tacplus_keys( tacplus_opt_key );
+}
+
+void
+proto_register_tacplus(void)
+{
+	static hf_register_info hf[] = {
+	  { &hf_tacplus_response,
+	    { "Response",           "tacplus.response",
+	      FT_BOOLEAN, BASE_NONE, NULL, 0x0,
+	      "TRUE if TACACS+ response", HFILL }},
+	  { &hf_tacplus_request,
+	    { "Request",            "tacplus.request",
+	      FT_BOOLEAN, BASE_NONE, NULL, 0x0,
+	      "TRUE if TACACS+ request", HFILL }},
+	  { &hf_tacplus_majvers,
+	    { "Major version",      "tacplus.majvers",
+	      FT_UINT8, BASE_DEC, NULL, 0x0,
+	      "Major version number", HFILL }},
+	  { &hf_tacplus_minvers,
+	    { "Minor version",      "tacplus.minvers",
+	      FT_UINT8, BASE_DEC, NULL, 0x0,
+	      "Minor version number", HFILL }},
+	  { &hf_tacplus_type,
+	    { "Type",               "tacplus.type",
+	      FT_UINT8, BASE_DEC, VALS(tacplus_type_vals), 0x0,
+	      "Type", HFILL }},
+	  { &hf_tacplus_seqno,
+	    { "Sequence number",    "tacplus.seqno",
+	      FT_UINT8, BASE_DEC, NULL, 0x0,
+	      "Sequence number", HFILL }},
+	  { &hf_tacplus_flags,
+	    { "Flags",              "tacplus.flags",
+	      FT_UINT8, BASE_HEX, NULL, 0x0,
+	      "Flags", HFILL }},
+	  { &hf_tacplus_flags_payload_type,
+	    { "Unencrypted",       "tacplus.flags.unencrypted",
+	      FT_BOOLEAN, 8, TFS(&flags_set_truth), FLAGS_UNENCRYPTED,
+	      "Is payload unencrypted?", HFILL }},
+	  { &hf_tacplus_flags_connection_type,
+	    { "Single Connection",    "tacplus.flags.singleconn",
+	      FT_BOOLEAN, 8, TFS(&flags_set_truth), FLAGS_SINGLE,
+	      "Is this a single connection?", HFILL }},
+	  { &hf_tacplus_acct_flags,
+	    { "Flags",    "tacplus.acct.flags",
+	      FT_UINT8, BASE_HEX, NULL, 0x0,
+	      "Flags", HFILL }},
+	  { &hf_tacplus_session_id,
+	    { "Session ID",         "tacplus.session_id",
+	      FT_UINT32, BASE_DEC, NULL, 0x0,
+	      "Session ID", HFILL }},
+	  { &hf_tacplus_packet_len,
+	    { "Packet length",      "tacplus.packet_len",
+	      FT_UINT32, BASE_DEC, NULL, 0x0,
+	      "Packet length", HFILL }}
+	};
+	static gint *ett[] = {
+		&ett_tacplus,
+		&ett_tacplus_flags,
+		&ett_tacplus_acct_flags,
+		&ett_tacplus_body,
+		&ett_tacplus_body_chap, 
+	};
+	module_t *tacplus_module;
+
+	proto_tacplus = proto_register_protocol("TACACS+", "TACACS+", "tacplus");
+	proto_register_field_array(proto_tacplus, hf, array_length(hf));
+	proto_register_subtree_array(ett, array_length(ett));
+	tacplus_module = prefs_register_protocol (proto_tacplus, tacplus_pref_cb );
+	prefs_register_string_preference ( tacplus_module, "key",
+	"TACACS+ Encryption Key", "TACACS+ Encryption Key", &tacplus_opt_key );
+}
+
+void
+proto_reg_handoff_tacplus(void)
+{
+	dissector_handle_t tacplus_handle;
+
+	tacplus_handle = create_dissector_handle(dissect_tacplus,
+	    proto_tacplus);
+	dissector_add("tcp.port", TCP_PORT_TACACS, tacplus_handle);
+}
+
+
+#define MD5_LEN 16
+
+static void
+md5_xor( guint8 *data, char *key, int data_len, guint8 *session_id, guint8 version, guint8 seq_no )
+{
+	int i,j,md5_len;
+	md5_byte_t *md5_buff;
+	md5_byte_t hash[MD5_LEN];       				/* the md5 hash */
+	md5_byte_t *mdp;
+	md5_state_t mdcontext;
+
+	md5_len = 4 /* sizeof(session_id) */ + strlen(key)
+			+ sizeof(version) + sizeof(seq_no);
+	
+	md5_buff = (md5_byte_t*)g_malloc(md5_len+MD5_LEN);
+
+
+	mdp = md5_buff;
+	*(guint32*)mdp = *(guint32*)session_id;
+	mdp += 4 ;
+	memcpy(mdp, key, strlen(key));
+	mdp += strlen(key);
+	*mdp++ = version;
+	*mdp++ = seq_no;
+
+
+	md5_init(&mdcontext);
+	md5_append(&mdcontext, md5_buff, md5_len);
+	md5_finish(&mdcontext,hash);
+	md5_len += MD5_LEN;
+	for (i = 0; i < data_len; i += 16) {
+
+		for (j = 0; j < 16; j++) {
+			if ((i + j) >= data_len)  {
+				i = data_len+1; /* To exit from the external loop  */
+				break;
+			}
+			data[i + j] ^= hash[j];
+		}
+		memcpy(mdp, hash, MD5_LEN);
+		md5_init(&mdcontext);
+		md5_append(&mdcontext, md5_buff, md5_len);
+		md5_finish(&mdcontext,hash);
+	}
+	g_free( md5_buff );
+}