Wireshark-dev: Re: [Wireshark-dev] Kismet protocol dissector
From: "Krzysztof Burghardt" <[email protected]>
Date: Thu, 13 Jul 2006 11:53:54 +0200 (CEST)
> wiki.wireshark.org/SampleCaptures  and then link to these captures
[...]
> can you move them to /SampleCaptures and link there from the protocol
> page

Sure, done.

> You put the braces for compound statement differently from the rest of
> wireshark coding style
> which (most of the time/often) is
>    if (expression)  {

Ups, I did it again ;->
It's fixed now (indent -gnu -br). Patch attached.

> Ports only become WellKnown if it is IANA that assigns them.

Right, fixed this in wiki.

Regards,
-- 
Krzysztof Burghardt <[email protected]>
http://www.burghardt.pl/
Index: epan/dissectors/packet-kismet.c
===================================================================
--- epan/dissectors/packet-kismet.c	(revision 0)
+++ epan/dissectors/packet-kismet.c	(revision 0)
@@ -0,0 +1,351 @@
+/* packet-kismet.c
+ * Routines for kismet packet dissection
+ * Copyright 2006, Krzysztof Burghardt <[email protected]>
+ *
+ * $Id$
+ *
+ * Ethereal - Network traffic analyzer
+ * By Gerald Combs <[email protected]>
+ * Copyright 1998 Gerald Combs
+ *
+ * Copied from packet-pop.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.
+ */
+
+#ifdef HAVE_CONFIG_H
+# include "config.h"
+#endif
+
+#include <stdio.h>
+
+#include <string.h>
+#include <glib.h>
+#include <epan/packet.h>
+#include <epan/strutil.h>
+#include <epan/prefs.h>
+
+static int proto_kismet = -1;
+static int hf_kismet_response = -1;
+static int hf_kismet_request = -1;
+
+static gint ett_kismet = -1;
+static gint ett_kismet_reqresp = -1;
+
+static dissector_handle_t data_handle;
+
+#define TCP_PORT_KISMET	2501
+
+static guint global_kismet_tcp_port = TCP_PORT_KISMET;
+static guint tcp_port = 0;
+
+static gboolean response_is_continuation (const guchar * data);
+void proto_reg_handoff_kismet (void);
+void proto_register_kismet (void);
+
+static gboolean
+dissect_kismet (tvbuff_t * tvb, packet_info * pinfo, proto_tree * tree)
+{
+  gboolean is_request;
+  gboolean is_continuation;
+  proto_tree *kismet_tree, *reqresp_tree;
+  proto_item *ti;
+  proto_item *tmp_item;
+  gint offset = 0;
+  const guchar *line;
+  gint next_offset;
+  int linelen;
+  int tokenlen;
+  int i;
+  const guchar *next_token;
+
+  /*
+   * Find the end of the first line.
+   *
+   * Note that "tvb_find_line_end()" will return a value that is
+   * not longer than what's in the buffer, so the "tvb_get_ptr()"
+   * call won't throw an exception.
+   */
+  linelen = tvb_find_line_end (tvb, offset, -1, &next_offset, FALSE);
+  line = tvb_get_ptr (tvb, offset, linelen);
+
+  /*
+   * Check if it is an ASCII based protocol with reasonable length
+   * packets, if not return, and try annother dissector.
+   */
+  if (linelen < 8) {
+    /*
+     * Packet is too short
+     */
+    return FALSE;
+  }
+  else {
+    for (i = 0; i < 8; ++i) {
+      /*
+       * Packet contains non-ASCII data
+       */
+      if (line[i] < 32 || line[i] > 128)
+	return FALSE;
+    }
+  }
+
+  /*
+   * If it is Kismet traffic set COL_PROTOCOL.
+   */
+  if (check_col (pinfo->cinfo, COL_PROTOCOL))
+    col_set_str (pinfo->cinfo, COL_PROTOCOL, "kismet");
+
+  /*
+   * Check if it is request, reply or continuation.
+   */
+  if (pinfo->match_port == pinfo->destport) {
+    is_request = TRUE;
+    is_continuation = FALSE;
+  }
+  else {
+    is_request = FALSE;
+    is_continuation = response_is_continuation (line);
+  }
+
+  if (check_col (pinfo->cinfo, COL_INFO)) {
+    /*
+     * Put the first line from the buffer into the summary
+     * if it's a kismet request or reply (but leave out the
+     * line terminator).
+     * Otherwise, just call it a continuation.
+     */
+    if (is_continuation)
+      col_set_str (pinfo->cinfo, COL_INFO, "Continuation");
+    else
+      col_add_fstr (pinfo->cinfo, COL_INFO, "%s: %s",
+		    is_request ? "Request" : "Response",
+		    format_text (line, linelen));
+  }
+
+  if (tree) {
+    ti = proto_tree_add_item (tree, proto_kismet, tvb, offset, -1, FALSE);
+    kismet_tree = proto_item_add_subtree (ti, ett_kismet);
+
+    if (is_continuation) {
+      /*
+       * Put the whole packet into the tree as data.
+       */
+      call_dissector (data_handle, tvb, pinfo, kismet_tree);
+      return TRUE;
+    }
+
+    if (is_request) {
+      tmp_item = proto_tree_add_boolean (kismet_tree,
+					 hf_kismet_request, tvb, 0, 0, TRUE);
+    }
+    else {
+      tmp_item = proto_tree_add_boolean (kismet_tree,
+					 hf_kismet_response, tvb, 0, 0, TRUE);
+    }
+    PROTO_ITEM_SET_GENERATED (tmp_item);
+
+    while (tvb_offset_exists (tvb, offset)) {
+      /*
+       * Find the end of the line.
+       */
+      linelen = tvb_find_line_end (tvb, offset, -1, &next_offset, FALSE);
+
+      if (linelen) {
+	/*
+	 * Put this line.
+	 */
+	ti = proto_tree_add_text (kismet_tree, tvb, offset,
+				  next_offset - offset, "%s",
+				  tvb_format_text (tvb, offset,
+						   next_offset - offset - 1));
+	reqresp_tree = proto_item_add_subtree (ti, ett_kismet_reqresp);
+	tokenlen = get_token_len (line, line + linelen, &next_token);
+	if (tokenlen != 0) {
+	  guint8 *reqresp;
+	  reqresp = tvb_get_ephemeral_string (tvb, offset, tokenlen);
+	  if (is_request) {
+	    /*
+	     * No request dissection
+	     */
+	  }
+	  else {
+	    /*
+	     * *KISMET: {Version} {Start time} \001{Server name}\001 {Build Revision}
+	     * two fields left undocumented: {???} {?ExtendedVersion?}
+	     */
+	    if (strncmp (reqresp, "*KISMET", strlen ("*KISMET")) == 0) {
+	      offset += next_token - line;
+	      linelen -= next_token - line;
+	      line = next_token;
+	      tokenlen = get_token_len (line, line + linelen, &next_token);
+	      proto_tree_add_text (reqresp_tree, tvb, offset,
+				   tokenlen, "Kismet version: %s",
+				   format_text (line, tokenlen));
+
+	      offset += next_token - line;
+	      linelen -= next_token - line;
+	      line = next_token;
+	      tokenlen = get_token_len (line, line + linelen, &next_token);
+	      proto_tree_add_text (reqresp_tree, tvb, offset,
+				   tokenlen, "Start time: %s",
+				   format_text (line, tokenlen));
+
+	      offset += next_token - line;
+	      linelen -= next_token - line;
+	      line = next_token;
+	      tokenlen = get_token_len (line, line + linelen, &next_token);
+	      proto_tree_add_text (reqresp_tree, tvb, offset,
+				   tokenlen, "Server name: %s",
+				   format_text (line + 1, tokenlen - 2));
+
+	      offset += next_token - line;
+	      linelen -= next_token - line;
+	      line = next_token;
+	      tokenlen = get_token_len (line, line + linelen, &next_token);
+	      proto_tree_add_text (reqresp_tree, tvb, offset,
+				   tokenlen, "Build revision: %s",
+				   format_text (line, tokenlen));
+
+	      offset += next_token - line;
+	      linelen -= next_token - line;
+	      line = next_token;
+	      tokenlen = get_token_len (line, line + linelen, &next_token);
+	      proto_tree_add_text (reqresp_tree, tvb, offset,
+				   tokenlen, "Unknown field: %s",
+				   format_text (line, tokenlen));
+
+	      offset += next_token - line;
+	      linelen -= next_token - line;
+	      line = next_token;
+	      tokenlen = get_token_len (line, line + linelen, &next_token);
+	      proto_tree_add_text (reqresp_tree, tvb, offset,
+				   tokenlen,
+				   "Extended version string: %s",
+				   format_text (line, tokenlen));
+	    }
+	    /*
+	     * *TIME: {Time}
+	     */
+	    if (strncmp (reqresp, "*TIME", strlen ("*TIME")) == 0) {
+	      time_t t;
+	      char *ptr;
+
+	      offset += next_token - line;
+	      linelen -= next_token - line;
+	      line = next_token;
+	      tokenlen = get_token_len (line, line + linelen, &next_token);
+
+	      /*
+	       * Convert form ascii to time_t
+	       */
+	      t = atoi (format_text (line, tokenlen));
+
+	      /*
+	       * Format ascii representation of time
+	       */
+	      ptr = ctime (&t);
+	      /*
+	       * Delete final '\n'
+	       */
+	      ptr[strlen (ptr) - 1] = 0;
+
+	      proto_tree_add_text (reqresp_tree, tvb, offset,
+				   tokenlen, "Time: %s", ptr);
+	    }
+	  }
+	  offset += next_token - line;
+	  linelen -= next_token - line;
+	  line = next_token;
+	}
+      }
+      offset = next_offset;
+    }
+  }
+  return TRUE;
+}
+
+static gboolean
+response_is_continuation (const guchar * data)
+{
+  if (strncmp (data, "*", strlen ("*")) == 0)
+    return FALSE;
+
+  if (strncmp (data, "!", strlen ("!")) == 0)
+    return FALSE;
+
+  return TRUE;
+}
+
+void
+proto_register_kismet (void)
+{
+
+  static hf_register_info hf[] = {
+    {&hf_kismet_response,
+     {"Response", "kismet.response",
+      FT_BOOLEAN, BASE_NONE, NULL, 0x0,
+      "TRUE if kismet response", HFILL}},
+
+    {&hf_kismet_request,
+     {"Request", "kismet.request",
+      FT_BOOLEAN, BASE_NONE, NULL, 0x0,
+      "TRUE if kismet request", HFILL}}
+  };
+  static gint *ett[] = {
+    &ett_kismet,
+    &ett_kismet_reqresp,
+  };
+  module_t *kismet_module;
+
+  proto_kismet =
+    proto_register_protocol ("Kismet Client/Server Protocol", "Kismet",
+			     "kismet");
+  proto_register_field_array (proto_kismet, hf, array_length (hf));
+  proto_register_subtree_array (ett, array_length (ett));
+
+  /* Register our configuration options for Kismet, particularly our port */
+
+  kismet_module =
+    prefs_register_protocol (proto_kismet, proto_reg_handoff_kismet);
+
+  prefs_register_uint_preference (kismet_module, "tcp.port",
+				  "Kismet Server TCP Port",
+				  "Set the port for Kismet Client/Server messages (if other"
+				  " than the default of 2501)", 10,
+				  &global_kismet_tcp_port);
+}
+
+void
+proto_reg_handoff_kismet (void)
+{
+  static int kismet_prefs_initialized = FALSE;
+  static dissector_handle_t kismet_handle;
+
+  if (!kismet_prefs_initialized) {
+    kismet_handle =
+      new_create_dissector_handle (dissect_kismet, proto_kismet);
+    kismet_prefs_initialized = TRUE;
+  }
+  else {
+    dissector_delete ("tcp.port", tcp_port, kismet_handle);
+  }
+
+  /* Set our port number for future use */
+
+  tcp_port = global_kismet_tcp_port;
+
+  dissector_add ("tcp.port", global_kismet_tcp_port, kismet_handle);
+  data_handle = find_dissector ("data");
+}
Index: epan/dissectors/Makefile.common
===================================================================
--- epan/dissectors/Makefile.common	(revision 18189)
+++ epan/dissectors/Makefile.common	(working copy)
@@ -394,6 +394,7 @@
 	packet-kerberos4.c	\
 	packet-klm.c	\
 	packet-kink.c	\
+	packet-kismet.c	\
 	packet-kpasswd.c	\
 	packet-l2tp.c	\
 	packet-lapb.c	\