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Wireshark-dev: [Wireshark-dev] ATM Dissector Enhancement

From: "McAtee, Kip" <Kip.McAtee@xxxxxxxxxxx>
Date: Tue, 24 Jun 2008 14:01:39 -1000

Greetings-

 

Here are the changes we propose for the packet-atm dissector:

 

Index: epan/dissectors/packet-atm.c

===================================================================

--- epan/dissectors/packet-atm.c        (revision 25594)

+++ epan/dissectors/packet-atm.c        (working copy)

@@ -69,6 +69,9 @@

 static dissector_handle_t lane_handle;

 static dissector_handle_t ilmi_handle;

 static dissector_handle_t fp_handle;

+static dissector_handle_t ppp_handle;

+static dissector_handle_t eth_handle;

+static dissector_handle_t ip_handle;

 static dissector_handle_t data_handle;

 

 static gboolean dissect_lanesscop = FALSE;

@@ -1106,11 +1109,61 @@

       break;

 

     default:

-      if (tree) {

-        /* Dump it as raw data. */

-        call_dissector(data_handle, next_tvb, pinfo, tree);

-        break;

+      {

+        gboolean decoded = FALSE;

+

+        if (tvb_length(next_tvb) > 20) /* arbitrary size */

+        {

+            guint8 octet[8];

+            tvb_memcpy(next_tvb, octet, 0, sizeof(octet));

+

+            decoded = TRUE;

+            if (octet[0] == 0x00 && octet[1] == 0x21)

+            {

+                call_dissector(ppp_handle, next_tvb, pinfo, tree);

+            }

+            else if (octet[0] == 0x00 && octet[1] == 0x00)

+            {

+                /* assume vc muxed bridged ethernet */

+                proto_tree_add_text(tree, tvb, 0, 2, "Pad: 0x0000");

+                next_tvb = tvb_new_subset(tvb, 2, -1, -1);

+                call_dissector(eth_handle, next_tvb, pinfo, tree);

+            }

+            else if (octet[2] == 0x03    && // NLPID

+                    ((octet[3] == 0xcc   || // IPv4

+                      octet[3] == 0x8e)  || // IPv6

+                     (octet[3] == 0x00   && // Eth

+                      octet[4] == 0x80)))  // Eth

+            {

+                /* assume network interworking with FR 2 byte header */

+                call_dissector(fr_handle, next_tvb, pinfo, tree);

+            }

+            else if (octet[4] == 0x03    && // NLPID

+                    ((octet[5] == 0xcc   || // IPv4

+                      octet[5] == 0x8e)  || // IPv6

+                     (octet[5] == 0x00   && // Eth

+                      octet[6] == 0x80)))   // Eth

+            {

+                /* assume network interworking with FR 4 byte header */

+                call_dissector(fr_handle, next_tvb, pinfo, tree);

+            }

+            else if ((octet[0] == 0x45) ||

+                     ((octet[0] & 0xf0) == 0x60))

+            {

+                call_dissector(ip_handle, next_tvb, pinfo, tree);

+            }

+            else

+            {

+                decoded = FALSE;

+            }

+        }

+

+        if (tree && !decoded) {

+            /* Dump it as raw data. */

+            call_dissector(data_handle, next_tvb, pinfo, tree);

+        }

       }

+      break;

     }

     break;

 

@@ -1729,6 +1782,9 @@

        sscop_handle = find_dissector("sscop");

        lane_handle = find_dissector("lane");

        ilmi_handle = find_dissector("ilmi");

+    ppp_handle = find_dissector("ppp");

+    eth_handle = find_dissector("eth");

+    ip_handle = find_dissector("ip");

        data_handle = find_dissector("data");

        fp_handle = find_dissector("fp");

 




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