Add a dissector "mac-lte-framed" that uses the same framing format as

the existing "mac-lte" UDP heuristic dissector. It is hoped that it will be
possible to register a DLT for use with this format.

svn path=/trunk/; revision=40580

1 files changed, 115 insertions, 0 deletions

diff --git a/epan/dissectors/packet-mac-lte-framed.c b/epan/dissectors/packet-mac-lte-framed.c
new file mode 100644
index 0000000000..f3b8788557
--- /dev/null
+++ b/epan/dissectors/packet-mac-lte-framed.c
@@ -0,0 +1,115 @@
+/* Routines for MAC LTE format files with context info as header.
+ *
+ * Martin Mathieson
+ *
+ * $Id$
+ *
+ * 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
+ * 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 <epan/packet.h>
+
+#include "packet-mac-lte.h"
+
+/*
+ * Doesn't do a detailed dissection of the lines of the message, just treat as text.
+ */
+
+
+/* Initialize the protocol and registered fields. */
+static int proto_mac_lte_framed = -1;
+
+extern int proto_mac_lte;
+
+/* Main dissection function. */
+static void dissect_mac_lte_framed(tvbuff_t *tvb, packet_info *pinfo,
+                                   proto_tree *tree)
+{
+    gint                 offset = 0;
+    struct mac_lte_info  *p_mac_lte_info;
+    tvbuff_t             *mac_tvb;
+    gboolean             infoAlreadySet = FALSE;
+    dissector_handle_t   mac_lte_handle = find_dissector("mac-lte");
+    if (!mac_lte_handle) {
+        return;
+    }
+
+    /* Do this again on re-dissection to re-discover offset of actual PDU */
+
+    /* Needs to be at least as long as:
+       - fixed header bytes
+       - tag for data
+       - at least one byte of MAC PDU payload */
+    if ((size_t)tvb_length_remaining(tvb, offset) < (3+2)) {
+        return;
+    }
+
+    /* If redissecting, use previous info struct (if available) */
+    p_mac_lte_info = p_get_proto_data(pinfo->fd, proto_mac_lte);
+    if (p_mac_lte_info == NULL) {
+        /* Allocate new info struct for this frame */
+        p_mac_lte_info = se_alloc0(sizeof(struct mac_lte_info));
+        infoAlreadySet = FALSE;
+    }
+    else {
+        infoAlreadySet = TRUE;
+    }
+
+    /* Dissect the fields to populate p_mac_lte */
+    if (!dissect_mac_lte_context_fields(p_mac_lte_info, tvb, &offset)) {
+        return;
+    }
+
+
+    if (!infoAlreadySet) {
+        /* Store info in packet */
+        p_add_proto_data(pinfo->fd, proto_mac_lte, p_mac_lte_info);
+    }
+
+    /**************************************/
+    /* OK, now dissect as MAC LTE         */
+
+    /* Create tvb that starts at actual MAC PDU */
+    mac_tvb = tvb_new_subset(tvb, offset, -1, tvb_reported_length(tvb)-offset);
+    call_dissector_only(mac_lte_handle, mac_tvb, pinfo, tree);
+}
+
+void proto_register_mac_lte_framed(void)
+{
+    static hf_register_info hf[] =
+    {
+    };
+
+    static gint *ett[] =
+    {
+    };
+
+    /* Register protocol. */
+    proto_mac_lte_framed = proto_register_protocol("mac-lte-framed", "MAC-LTE-FRAMED", "mac-lte-framed");
+    proto_register_field_array(proto_mac_lte_framed, hf, array_length(hf));
+    proto_register_subtree_array(ett, array_length(ett));
+
+    /* Allow other dissectors to find this one by name. */
+    register_dissector("mac-lte-framed", dissect_mac_lte_framed, proto_mac_lte_framed);
+}
+