--- /dev/null
+/* packet-ax25-kiss.c
+ *
+ * Routines for AX.25 KISS protocol dissection
+ * Copyright 2010,2012 R.W. Stearn <richard@rns-stearn.demon.co.uk>
+ *
+ * $Id$
+ *
+ * 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.
+ */
+
+/*
+ * This dissector handles the "KISS" protocol as implemented by the
+ * Linux kernel.
+ *
+ * The original definition of the KISS protocol can be found here:
+ * http://www.ka9q.net/papers/kiss.html
+ * and here:
+ * http://www.ax25.net/kiss.aspx
+ *
+ * Linux implementation does not appear to attempt to implement that
+ * protocol in full. Does provide the ability to send a KISS command via
+ * ax25_kiss_cmd() and internally will send FULLDUPLEX KISS commands if
+ * DAMA is enabled/disabled.
+ * i.e.:
+ * ax25_dev_dama_on sends FullDuplex ON
+ * ax25_dev_dama_off sends FullDuplex OFF
+ *
+ * Data frames are prefixed with a "Data Frame" command but the port appears to
+ * be always 0.
+ *
+ * Abstract from http://www.ka9q.net/papers/kiss.html
+ * --------------------------------------------------
+ * For reference the first byte of a KISS frame is the frame type and the TNC
+ * port number,
+ * LSB 4 bits = frame type,
+ * MSB 4 bits = port number.
+ *
+ * The frame types are:
+ * Command Function Comments
+ * 0 Data frame The rest of the frame is data to
+ * be sent on the HDLC channel.
+ *
+ * 1 TXDELAY The next byte is the transmitter
+ * keyup delay in 10 ms units.
+ * The default start-up value is 50
+ * (i.e., 500 ms).
+ *
+ * 2 P The next byte is the persistence
+ * parameter, p, scaled to the range
+ * 0 - 255 with the following
+ * formula:
+ *
+ * P = p * 256 - 1
+ *
+ * The default value is P = 63
+ * (i.e., p = 0.25).
+ *
+ * 3 SlotTime The next byte is the slot interval
+ * in 10 ms units.
+ * The default is 10 (i.e., 100ms).
+ *
+ * 4 TXtail The next byte is the time to hold
+ * up the TX after the FCS has been
+ * sent, in 10 ms units. This command
+ * is obsolete, and is included here
+ * only for compatibility with some
+ * existing implementations.
+ *
+ * 5 FullDuplex The next byte is 0 for half duplex,
+ * nonzero for full duplex.
+ * The default is 0
+ * (i.e., half duplex).
+ *
+ * 6 SetHardware Specific for each TNC. In the
+ * TNC-1, this command sets the
+ * modem speed. Other implementations
+ * may use this function for other
+ * hardware-specific functions.
+ *
+ * FF Return Exit KISS and return control to a
+ * higher-level program. This is useful
+ * only when KISS is incorporated
+ * into the TNC along with other
+ * applications.
+ *
+*/
+
+#ifdef HAVE_CONFIG_H
+# include "config.h"
+#endif
+
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+
+#include <glib.h>
+
+#include <epan/strutil.h>
+#include <epan/packet.h>
+#include <epan/prefs.h>
+#include <epan/emem.h>
+#include <epan/etypes.h>
+
+#include "packet-ax25-kiss.h"
+
+#define STRLEN 80
+
+#define KISS_HEADER_SIZE 1 /* length of the KISS type header */
+
+/* KISS frame types */
+#define KISS_DATA_FRAME 0
+#define KISS_TXDELAY 1
+#define KISS_PERSISTENCE 2
+#define KISS_SLOT_TIME 3
+#define KISS_TXTAIL 4
+#define KISS_FULLDUPLEX 5
+#define KISS_SETHARDWARE 6
+#define KISS_RETURN 15
+
+#define KISS_CMD_MASK 0x0f
+#define KISS_PORT_MASK 0xf0
+
+/* Forward declaration we need below */
+void proto_reg_handoff_ax25_kiss(void);
+
+/* Dissector handles - all the possibles are listed */
+
+/* Initialize the protocol and registered fields */
+static int proto_ax25_kiss = -1;
+static int hf_ax25_kiss_cmd = -1;
+static int hf_ax25_kiss_port = -1;
+static int hf_ax25_kiss_txdelay = -1;
+static int hf_ax25_kiss_persistence = -1;
+static int hf_ax25_kiss_slottime = -1;
+static int hf_ax25_kiss_txtail = -1;
+static int hf_ax25_kiss_fullduplex = -1;
+static int hf_ax25_kiss_sethardware = -1;
+
+/* Global preference ("controls" display of numbers) */
+/*
+static gboolean gPREF_HEX = FALSE;
+*/
+
+/* Initialize the subtree pointers */
+static gint ett_ax25_kiss = -1;
+
+/* Code to actually dissect the packets */
+static void
+dissect_ax25_kiss( tvbuff_t *tvb, packet_info *pinfo, proto_tree *parent_tree )
+{
+ proto_item *ti;
+ proto_tree *kiss_tree;
+ int offset;
+ int kiss_cmd;
+ int kiss_type;
+ int kiss_port;
+ int kiss_param;
+ int kiss_param_len;
+ char *frame_type_text;
+ char *info_buffer;
+#if 0
+ void *saved_private_data;
+ tvbuff_t *next_tvb = NULL;
+#endif
+
+
+ info_buffer = ep_alloc( STRLEN );
+ info_buffer[0]='\0';
+
+ if ( check_col( pinfo->cinfo, COL_PROTOCOL ) )
+ col_set_str( pinfo->cinfo, COL_PROTOCOL, "KISS" );
+
+ col_clear( pinfo->cinfo, COL_INFO );
+
+ /* protocol offset for the KISS header */
+ offset = 0;
+
+ kiss_cmd = tvb_get_guint8( tvb, offset ) & 0xff;
+ kiss_type = kiss_cmd & KISS_CMD_MASK;
+ kiss_port = (kiss_cmd & KISS_PORT_MASK) >> 4;
+ offset += KISS_HEADER_SIZE;
+
+ frame_type_text = "????";
+ kiss_param = 0;
+ kiss_param_len = 0;
+ switch ( kiss_type )
+ {
+ case KISS_DATA_FRAME : frame_type_text = "Data frame"; break;
+ case KISS_TXDELAY : frame_type_text = "Tx Delay"; kiss_param_len = 1; kiss_param = tvb_get_guint8( tvb, offset ) & 0xff; break;
+ case KISS_PERSISTENCE : frame_type_text = "Persistence"; kiss_param_len = 1; kiss_param = tvb_get_guint8( tvb, offset ) & 0xff; break;
+ case KISS_SLOT_TIME : frame_type_text = "Slot time"; kiss_param_len = 1; kiss_param = tvb_get_guint8( tvb, offset ) & 0xff; break;
+ case KISS_TXTAIL : frame_type_text = "Tx tail"; kiss_param_len = 1; kiss_param = tvb_get_guint8( tvb, offset ) & 0xff; break;
+ case KISS_FULLDUPLEX : frame_type_text = "Full duplex"; kiss_param_len = 1; kiss_param = tvb_get_guint8( tvb, offset ) & 0xff; break;
+ case KISS_SETHARDWARE : frame_type_text = "Set hardware"; kiss_param_len = 1; kiss_param = tvb_get_guint8( tvb, offset ) & 0xff; break;
+ case KISS_RETURN : frame_type_text = "Return"; break;
+ default : break;
+ }
+ g_snprintf( info_buffer, STRLEN, "%s, Port %u", frame_type_text, kiss_port );
+ if ( kiss_param_len > 0 )
+ g_snprintf( info_buffer, STRLEN, "%s %u, Port %u", frame_type_text, kiss_param,
+ kiss_port );
+
+ offset += kiss_param_len;
+
+ col_add_str( pinfo->cinfo, COL_INFO, info_buffer );
+
+ if ( parent_tree )
+ {
+ /* protocol offset for the KISS header */
+ offset = 0;
+
+ /* create display subtree for the protocol */
+ ti = proto_tree_add_protocol_format( parent_tree, proto_ax25_kiss, tvb, offset,
+ KISS_HEADER_SIZE + kiss_param_len,
+ "KISS: %s",
+ info_buffer
+ );
+
+ kiss_tree = proto_item_add_subtree( ti, ett_ax25_kiss );
+
+ proto_tree_add_uint( kiss_tree, hf_ax25_kiss_cmd, tvb, offset, KISS_HEADER_SIZE,
+ kiss_cmd );
+ proto_tree_add_uint( kiss_tree, hf_ax25_kiss_port, tvb, offset, KISS_HEADER_SIZE,
+ kiss_cmd );
+ offset += KISS_HEADER_SIZE;
+
+ switch ( kiss_type )
+ {
+ case KISS_DATA_FRAME : break;
+ case KISS_TXDELAY :
+ proto_tree_add_uint( kiss_tree, hf_ax25_kiss_txdelay,
+ tvb, offset, kiss_param_len, kiss_param );
+ offset += kiss_param_len;
+ break;
+ case KISS_PERSISTENCE :
+ proto_tree_add_uint( kiss_tree, hf_ax25_kiss_persistence,
+ tvb, offset, kiss_param_len, kiss_param );
+ offset += kiss_param_len;
+ break;
+ case KISS_SLOT_TIME :
+ proto_tree_add_uint( kiss_tree, hf_ax25_kiss_slottime,
+ tvb, offset, kiss_param_len, kiss_param );
+ offset += kiss_param_len;
+ break;
+ case KISS_TXTAIL :
+ proto_tree_add_uint( kiss_tree, hf_ax25_kiss_txtail,
+ tvb, offset, kiss_param_len, kiss_param );
+ offset += kiss_param_len;
+ break;
+ case KISS_FULLDUPLEX :
+ proto_tree_add_uint( kiss_tree, hf_ax25_kiss_fullduplex,
+ tvb, offset, kiss_param_len, kiss_param );
+ offset += kiss_param_len;
+ break;
+ case KISS_SETHARDWARE :
+ proto_tree_add_uint( kiss_tree, hf_ax25_kiss_sethardware,
+ tvb, offset, kiss_param_len, kiss_param );
+ offset += kiss_param_len;
+ break;
+ case KISS_RETURN : break;
+ default : break;
+ }
+
+ }
+ /* Call sub-dissectors here */
+
+}
+
+void
+proto_register_ax25_kiss(void)
+{
+ module_t *ax25_kiss_module;
+
+ /* Setup list of header fields */
+ static hf_register_info hf[] = {
+ { &hf_ax25_kiss_cmd,
+ { "Cmd", "ax25_kiss.cmd",
+ FT_UINT8, BASE_DEC, NULL, KISS_CMD_MASK,
+ "Cmd", HFILL }
+ },
+ { &hf_ax25_kiss_port,
+ { "Port", "ax25_kiss.port",
+ FT_UINT8, BASE_DEC, NULL, KISS_PORT_MASK,
+ "Port", HFILL }
+ },
+ { &hf_ax25_kiss_txdelay,
+ { "Tx delay", "ax25_kiss.txdelay",
+ FT_UINT8, BASE_DEC, NULL, 0x0,
+ "Tx delay", HFILL }
+ },
+ { &hf_ax25_kiss_persistence,
+ { "Persistence", "ax25_kiss.persistence",
+ FT_UINT8, BASE_DEC, NULL, 0x0,
+ "Persistence", HFILL }
+ },
+ { &hf_ax25_kiss_slottime,
+ { "Slot time", "ax25_kiss.slottime",
+ FT_UINT8, BASE_DEC, NULL, 0x0,
+ "Slot time", HFILL }
+ },
+ { &hf_ax25_kiss_txtail,
+ { "Tx tail", "ax25_kiss.txtail",
+ FT_UINT8, BASE_DEC, NULL, 0x0,
+ "Tx tail", HFILL }
+ },
+ { &hf_ax25_kiss_fullduplex,
+ { "Full duplex", "ax25_kiss.fullduplex",
+ FT_UINT8, BASE_DEC, NULL, 0x0,
+ "Full duplex", HFILL }
+ },
+ { &hf_ax25_kiss_sethardware,
+ { "Set hardware", "ax25_kiss.sethardware",
+ FT_UINT8, BASE_DEC, NULL, 0x0,
+ "Set hardware", HFILL }
+ },
+ };
+
+ /* Setup protocol subtree array */
+ static gint *ett[] = {
+ &ett_ax25_kiss,
+ };
+
+ /* Register the protocol name and description */
+ proto_ax25_kiss = proto_register_protocol( "AX.25 KISS", "AX.25 KISS", "ax25_kiss" );
+
+ /* Register the dissector */
+ register_dissector( "ax25_kiss", dissect_ax25_kiss, proto_ax25_kiss );
+
+ /* Required function calls to register the header fields and subtrees used */
+ proto_register_field_array( proto_ax25_kiss, hf, array_length( hf ) );
+ proto_register_subtree_array( ett, array_length( ett ) );
+
+ /* Register preferences module */
+ ax25_kiss_module = prefs_register_protocol( proto_ax25_kiss, proto_reg_handoff_ax25_kiss );
+
+ /* Register any preference */
+/*
+ prefs_register_bool_preference( ax25_kiss_module, "showhex",
+ "Display numbers in Hex",
+ "Enable to display numerical values in hexadecimal.",
+ &gPREF_HEX );
+*/
+}
+
+void
+proto_reg_handoff_ax25_kiss(void)
+{
+ static gboolean inited = FALSE;
+
+ if( !inited ) {
+
+ dissector_handle_t kiss_handle;
+
+ kiss_handle = create_dissector_handle( dissect_ax25_kiss, proto_ax25_kiss );
+ dissector_add( "wtap_encap", WTAP_ENCAP_AX25_KISS, kiss_handle );
+
+ inited = TRUE;
+ }
+}
+
+void
+capture_ax25_kiss( const guchar *pd, int offset, int len, packet_counts *ld)
+{
+ int l_offset;
+ guint8 kiss_cmd;
+
+ if ( ! BYTES_ARE_IN_FRAME( offset, len, KISS_HEADER_SIZE ) ) {
+ ld->other++;
+ return;
+ }
+
+ l_offset = offset;
+ kiss_cmd = pd[ l_offset ];
+ l_offset += KISS_HEADER_SIZE; /* step over kiss header */
+ switch ( kiss_cmd & KISS_CMD_MASK )
+ {
+ case KISS_DATA_FRAME : break;
+ case KISS_TXDELAY : l_offset += 1; break;
+ case KISS_PERSISTENCE : l_offset += 1; break;
+ case KISS_SLOT_TIME : l_offset += 1; break;
+ case KISS_TXTAIL : l_offset += 1; break;
+ case KISS_FULLDUPLEX : l_offset += 1; break;
+ case KISS_SETHARDWARE : l_offset += 1; break;
+ case KISS_RETURN : break;
+ default : break;
+ }
+
+}
git.samba.org / metze / wireshark / wip.git / commitdiff