Add support for the Ethernet Configuration Testing Protocol.

svn path=/trunk/; revision=12074

3 files changed, 149 insertions, 14 deletions

diff --git a/epan/dissectors/Makefile.common b/epan/dissectors/Makefile.common
index 3b2d95c6ad..4e35af4b51 100644
--- a/epan/dissectors/Makefile.common
+++ b/epan/dissectors/Makefile.common
@@ -317,6 +317,7 @@ DISSECTOR_SRC =	\
 	packet-llc.c	\
 	packet-lmi.c	\
 	packet-lmp.c	\
+	packet-loop.c	\
 	packet-lpd.c	\
 	packet-lwapp.c	\
 	packet-m2pa.c	\
diff --git a/epan/dissectors/packet-ethertype.c b/epan/dissectors/packet-ethertype.c
index f1219e25a5..520ed84b8c 100644
--- a/epan/dissectors/packet-ethertype.c
+++ b/epan/dissectors/packet-ethertype.c
@@ -217,20 +217,9 @@ ethertype(guint16 etype, tvbuff_t *tvb, int offset_after_etype,
 		call_dissector(data_handle,next_tvb, pinfo, tree);
 
 		/* Label protocol */
-		switch (etype) {
-
-		case ETHERTYPE_LOOP:
-			if (check_col(pinfo->cinfo, COL_PROTOCOL)) {
-				col_add_fstr(pinfo->cinfo, COL_PROTOCOL, "LOOP");
-			}
-			break;
-
-		default:
-			if (check_col(pinfo->cinfo, COL_PROTOCOL)) {
-				col_add_fstr(pinfo->cinfo, COL_PROTOCOL, "0x%04x",
-				    etype);
-			}
-			break;
+		if (check_col(pinfo->cinfo, COL_PROTOCOL)) {
+			col_add_fstr(pinfo->cinfo, COL_PROTOCOL, "0x%04x",
+			    etype);
 		}
 		if (check_col(pinfo->cinfo, COL_INFO)) {
 			description = match_strval(etype, etype_vals);
diff --git a/epan/dissectors/packet-loop.c b/epan/dissectors/packet-loop.c
new file mode 100644
index 0000000000..3403b7cc90
--- /dev/null
+++ b/epan/dissectors/packet-loop.c
@@ -0,0 +1,145 @@
+/* packet-loop.c
+ * Routines for Ethernet loopback/Configuration Test Protocol dissection
+ *
+ * See
+ *
+ *	http://stuff.mit.edu/people/jhawk/ctp.html
+ *
+ * $Id$
+ *
+ * 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.
+ */
+
+#ifdef HAVE_CONFIG_H
+# include "config.h"
+#endif
+
+#include <glib.h>
+#include <epan/packet.h>
+#include "etypes.h"
+
+static int proto_loop = -1;
+static int hf_loop_skipcount = -1;
+static int hf_loop_function = -1;
+static int hf_loop_forwarding_address = -1;
+
+static gint ett_loop = -1;
+
+static dissector_handle_t data_handle;
+
+#define FUNC_REPLY		1
+#define FUNC_FORWARD_DATA	2
+
+static const value_string function_vals[] = {
+  { FUNC_REPLY, "Reply" },
+  { FUNC_FORWARD_DATA, "Forward Data" },
+  { 0, NULL }
+};
+
+static void
+dissect_loop(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree)
+{
+  proto_tree  *loop_tree = NULL;
+  proto_item  *ti;
+  guint16     function;
+  int         offset = 0;
+  gboolean    set_info = FALSE;
+  tvbuff_t    *next_tvb;
+
+  if (check_col(pinfo->cinfo, COL_PROTOCOL))
+    col_set_str(pinfo->cinfo, COL_PROTOCOL, "LOOP");
+  if (check_col(pinfo->cinfo, COL_INFO))
+    col_clear(pinfo->cinfo, COL_INFO);
+
+  if (tree) {
+    ti = proto_tree_add_item(tree, proto_loop, tvb, 0, -1, FALSE);
+    loop_tree = proto_item_add_subtree(ti, ett_loop);
+  }
+
+  for (;;) {
+    if (tree)
+      proto_tree_add_item(loop_tree, hf_loop_skipcount, tvb, offset, 2, FALSE);
+    offset += 2;
+    function = tvb_get_ntohs(tvb, 2);
+    if (!set_info) {
+      if (check_col(pinfo->cinfo, COL_INFO)) {
+        col_add_str(pinfo->cinfo, COL_INFO,
+                    val_to_str(function, function_vals, "Unknown function (%u)"));
+      }
+      set_info = TRUE;
+    }
+    if (tree)
+      proto_tree_add_uint(loop_tree, hf_loop_function, tvb, offset, 2, function);
+    offset += 2;
+    switch (function) {
+
+    case FUNC_REPLY:
+    default:
+      next_tvb = tvb_new_subset(tvb, 4, -1, -1);
+      call_dissector(data_handle, next_tvb, pinfo, tree);
+      return;
+
+    case FUNC_FORWARD_DATA:
+      if (tree)
+        proto_tree_add_item(loop_tree, hf_loop_forwarding_address, tvb, offset,
+                            6, FALSE);
+      offset += 6;
+      break;
+    }
+  }
+}
+
+void
+proto_register_loop(void)
+{
+  static hf_register_info hf[] = {
+    { &hf_loop_skipcount,
+      { "skipCount",		"loop.skipcount",
+	FT_UINT16,	BASE_DEC,	NULL,	0x0,
+      	"", HFILL }},
+
+    { &hf_loop_function,
+      { "function",		"loop.function",
+	FT_UINT16,	BASE_DEC,	VALS(function_vals),	0x0,
+      	"", HFILL }},
+
+    { &hf_loop_forwarding_address,
+      { "Forwarding address",		"loop.forwarding_address",
+	FT_ETHER,	BASE_NONE,	NULL,	0x0,
+      	"", HFILL }},
+  };
+  static gint *ett[] = {
+    &ett_loop,
+  };
+
+  proto_loop = proto_register_protocol("Configuration Test Protocol (loopback)",
+				      "LOOP", "loop");
+  proto_register_field_array(proto_loop, hf, array_length(hf));
+  proto_register_subtree_array(ett, array_length(ett));
+}
+
+void
+proto_reg_handoff_loop(void)
+{
+  dissector_handle_t loop_handle;
+
+  loop_handle = create_dissector_handle(dissect_loop, proto_loop);
+
+  dissector_add("ethertype", ETHERTYPE_LOOP, loop_handle);
+}