* 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>
+ * Wireshark - Network traffic analyzer
+ * By Gerald Combs <gerald@wireshark.org>
* Copyright 1998 Gerald Combs
*
* This program is free software; you can redistribute it and/or
*
* 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.
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
*/
/*
* 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
+ * The Linux implementation does not appear to attempt to implement that
+ * protocol in full. It 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.:
* 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
+ * into the TNC along with other
* applications.
*
+ *
+ * G8BPQ extensions:
+ *
+ * 12 Data frame Data with acknowledge request
+ *
+ * 14 Poll mode Set poll mode
+ *
+ * Checksum mode
+ *
*/
-#ifdef HAVE_CONFIG_H
-# include "config.h"
-#endif
-
-#include <stdio.h>
-#include <stdlib.h>
-#include <string.h>
-
-#include <glib.h>
+#include "config.h"
-#include <epan/strutil.h>
#include <epan/packet.h>
#include <epan/prefs.h>
-#include <epan/emem.h>
-#include <epan/etypes.h>
-
+#include <wiretap/wtap.h>
#include "packet-ax25-kiss.h"
+#include "packet-ax25.h"
#define STRLEN 80
-#define KISS_HEADER_SIZE 1 /* length of the KISS type header */
+#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_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_DATA_FRAME_ACK 12
+#define KISS_POLL_MODE 14
#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);
+/* Global preferences */
+static gboolean gPREF_CKSUM_MODE = FALSE;
-/* Dissector handles - all the possibles are listed */
+void proto_register_ax25_kiss(void);
+void proto_reg_handoff_ax25_kiss(void);
/* 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_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_txtail = -1;
static int hf_ax25_kiss_fullduplex = -1;
static int hf_ax25_kiss_sethardware = -1;
+static int hf_ax25_kiss_data_ack = -1;
+static int hf_ax25_kiss_cksum = -1;
-/* Global preference ("controls" display of numbers) */
-/*
-static gboolean gPREF_HEX = FALSE;
-*/
/* Initialize the subtree pointers */
static gint ett_ax25_kiss = -1;
+static dissector_handle_t kiss_handle;
+
+/* Dissector handles - all the possibles are listed */
+static dissector_handle_t ax25_handle;
+
+static const value_string kiss_frame_types[] = {
+ { KISS_DATA_FRAME, "Data frame" },
+ { KISS_TXDELAY, "Tx delay" },
+ { KISS_PERSISTENCE, "Persistence" },
+ { KISS_SLOT_TIME, "Slot time" },
+ { KISS_TXTAIL, "Tx tail" },
+ { KISS_FULLDUPLEX, "Full duplex" },
+ { KISS_SETHARDWARE, "Set hardware" },
+ { KISS_DATA_FRAME_ACK, "Data frame ack" },
+ { KISS_POLL_MODE, "Poll mode" },
+ { KISS_RETURN, "Return" },
+ { 0, NULL }
+};
+
+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 : capture_ax25( pd, l_offset, len, ld ); break;
+ case KISS_TXDELAY : break;
+ case KISS_PERSISTENCE : break;
+ case KISS_SLOT_TIME : break;
+ case KISS_TXTAIL : break;
+ case KISS_FULLDUPLEX : break;
+ case KISS_SETHARDWARE : break;
+ case KISS_DATA_FRAME_ACK: l_offset += 2; capture_ax25( pd, l_offset, len, ld ); break;
+ case KISS_POLL_MODE : break;
+ case KISS_RETURN : break;
+ default : break;
+ }
+}
+
/* 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" );
-
+ int offset;
+ int kiss_cmd;
+ int kiss_type;
+ int kiss_port;
+ int kiss_param;
+ int kiss_param_len;
+ int kiss_cksum;
+ int kiss_cksum_index;
+ int kiss_tvb_length;
+ const char *frame_type_text;
+ char *info_buffer;
+ tvbuff_t *next_tvb = NULL;
+
+ info_buffer = (char *)wmem_alloc( wmem_packet_scope(), STRLEN );
+ info_buffer[0] = '\0';
+
+ col_set_str( pinfo->cinfo, COL_PROTOCOL, "AX.25 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;
+ 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;
+ 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;
+ case KISS_TXDELAY : kiss_param_len = 1; kiss_param = tvb_get_guint8( tvb, offset ) & 0xff; break;
+ case KISS_PERSISTENCE : kiss_param_len = 1; kiss_param = tvb_get_guint8( tvb, offset ) & 0xff; break;
+ case KISS_SLOT_TIME : kiss_param_len = 1; kiss_param = tvb_get_guint8( tvb, offset ) & 0xff; break;
+ case KISS_TXTAIL : kiss_param_len = 1; kiss_param = tvb_get_guint8( tvb, offset ) & 0xff; break;
+ case KISS_FULLDUPLEX : kiss_param_len = 1; kiss_param = tvb_get_guint8( tvb, offset ) & 0xff; break;
+ case KISS_SETHARDWARE :
+ kiss_param_len = tvb_captured_length_remaining( tvb, offset );
+ if ( kiss_param_len < 0 )
+ kiss_param_len = 0;
+ if ( (kiss_param_len > 0) && gPREF_CKSUM_MODE )
+ kiss_param_len--;
+ break;
+ case KISS_DATA_FRAME_ACK: kiss_param_len = 2; kiss_param = tvb_get_guint8( tvb, offset ) & 0xff; break;
default : break;
}
+ frame_type_text = val_to_str(kiss_type, kiss_frame_types, "Unknown (%u)");
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 );
+ g_snprintf( info_buffer, STRLEN, "%s %u, Port %u", frame_type_text, kiss_param, kiss_port );
offset += kiss_param_len;
/* 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,
+ tvb_captured_length_remaining( tvb, offset ),
"KISS: %s",
info_buffer
);
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 );
+ kiss_port );
offset += KISS_HEADER_SIZE;
switch ( kiss_type )
offset += kiss_param_len;
break;
case KISS_SETHARDWARE :
- proto_tree_add_uint( kiss_tree, hf_ax25_kiss_sethardware,
+ proto_tree_add_item( kiss_tree, hf_ax25_kiss_sethardware,
+ tvb, offset, kiss_param_len, ENC_NA );
+ offset += kiss_param_len;
+ break;
+ case KISS_DATA_FRAME_ACK:
+ proto_tree_add_uint( kiss_tree, hf_ax25_kiss_data_ack,
tvb, offset, kiss_param_len, kiss_param );
offset += kiss_param_len;
break;
+ case KISS_POLL_MODE : break;
case KISS_RETURN : break;
default : break;
}
+ if ( gPREF_CKSUM_MODE )
+ {
+ kiss_cksum = 0;
+ kiss_tvb_length = tvb_captured_length_remaining( tvb, 0 ) - 1;
+ if ( kiss_tvb_length > 0 )
+ {
+ for ( kiss_cksum_index = 0; kiss_cksum_index < kiss_tvb_length; kiss_cksum_index++ )
+ kiss_cksum ^= (tvb_get_guint8( tvb, kiss_cksum_index ) & 0xff);
+ proto_tree_add_uint( kiss_tree, hf_ax25_kiss_cksum,
+ tvb, kiss_cksum_index, 1, kiss_cksum );
+ }
+ }
}
+
/* Call sub-dissectors here */
+ if ( ( kiss_type == KISS_DATA_FRAME ) || ( kiss_type == KISS_DATA_FRAME_ACK ) )
+ {
+ next_tvb = tvb_new_subset_remaining( tvb, offset );
+ call_dissector( ax25_handle, next_tvb, pinfo, parent_tree );
+ }
}
void
static hf_register_info hf[] = {
{ &hf_ax25_kiss_cmd,
{ "Cmd", "ax25_kiss.cmd",
- FT_UINT8, BASE_DEC, NULL, KISS_CMD_MASK,
- "Cmd", HFILL }
+ FT_UINT8, BASE_DEC, VALS(kiss_frame_types), KISS_CMD_MASK,
+ NULL, HFILL }
},
{ &hf_ax25_kiss_port,
{ "Port", "ax25_kiss.port",
FT_UINT8, BASE_DEC, NULL, KISS_PORT_MASK,
- "Port", HFILL }
+ NULL, HFILL }
},
{ &hf_ax25_kiss_txdelay,
{ "Tx delay", "ax25_kiss.txdelay",
FT_UINT8, BASE_DEC, NULL, 0x0,
- "Tx delay", HFILL }
+ NULL, HFILL }
},
{ &hf_ax25_kiss_persistence,
{ "Persistence", "ax25_kiss.persistence",
FT_UINT8, BASE_DEC, NULL, 0x0,
- "Persistence", HFILL }
+ NULL, HFILL }
},
{ &hf_ax25_kiss_slottime,
{ "Slot time", "ax25_kiss.slottime",
FT_UINT8, BASE_DEC, NULL, 0x0,
- "Slot time", HFILL }
+ NULL, HFILL }
},
{ &hf_ax25_kiss_txtail,
{ "Tx tail", "ax25_kiss.txtail",
FT_UINT8, BASE_DEC, NULL, 0x0,
- "Tx tail", HFILL }
+ NULL, HFILL }
},
{ &hf_ax25_kiss_fullduplex,
{ "Full duplex", "ax25_kiss.fullduplex",
FT_UINT8, BASE_DEC, NULL, 0x0,
- "Full duplex", HFILL }
+ NULL, HFILL }
},
{ &hf_ax25_kiss_sethardware,
{ "Set hardware", "ax25_kiss.sethardware",
- FT_UINT8, BASE_DEC, NULL, 0x0,
- "Set hardware", HFILL }
+ FT_BYTES, BASE_NONE, NULL, 0x0,
+ NULL, HFILL }
+ },
+ { &hf_ax25_kiss_data_ack,
+ { "Data ack", "ax25_kiss.data_ack",
+ FT_UINT16, BASE_DEC, NULL, 0x0,
+ NULL, HFILL }
+ },
+ { &hf_ax25_kiss_cksum,
+ { "Checksum", "ax25_kiss.cksum",
+ FT_UINT16, BASE_HEX, NULL, 0x0,
+ NULL, HFILL }
},
};
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 );
+ kiss_handle = 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 );
+ ax25_kiss_module = prefs_register_protocol( proto_ax25_kiss, NULL);
+
+ prefs_register_bool_preference(ax25_kiss_module, "showcksum",
+ "Set checksum mode",
+ "Enable checksum calculation.",
+ &gPREF_CKSUM_MODE );
- /* 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;
+ dissector_add_uint( "wtap_encap", WTAP_ENCAP_AX25_KISS, 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;
- }
+ /* only currently implemented for AX.25 */
+ ax25_handle = find_dissector( "ax25" );
}
-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;
- }
-
-}
+/*
+ * Editor modelines - http://www.wireshark.org/tools/modelines.html
+ *
+ * Local variables:
+ * c-basic-offset: 8
+ * tab-width: 8
+ * indent-tabs-mode: t
+ * End:
+ *
+ * vi: set shiftwidth=8 tabstop=8 noexpandtab:
+ * :indentSize=8:tabSize=8:noTabs=false:
+ */