Add dissector for Exablaze timestamping trailers

Change-Id: I2953b7441b5f55f653e93e066f1c23fdcb5be7c5
Reviewed-on: https://code.wireshark.org/review/28265
Petri-Dish: Alexis La Goutte <alexis.lagoutte@gmail.com>
Tested-by: Petri Dish Buildbot
Reviewed-by: Alexis La Goutte <alexis.lagoutte@gmail.com>
Reviewed-by: Anders Broman <a.broman58@gmail.com>

diff --git a/docbook/release-notes.asciidoc b/docbook/release-notes.asciidoc
index a8e19e66499defc951a0d56b32023fecdcd836ce..e607470845ae6f01b659923421beff5755818130 100644 (file)
--- a/docbook/release-notes.asciidoc
+++ b/docbook/release-notes.asciidoc
@@ -74,6 +74,7 @@ GSM-R protocol (User-to-User Information Element usage)
 S101 Lawo Emberplus transport frame
 GLOW Lawo Emberplus Data format
 STCSIG (Spirent Test Center Signature decoding for Ethernet and FibreChannel, disabled by default)
+Exablaze trailers
 --
 
 === Updated Protocol Support

diff --git a/epan/dissectors/CMakeLists.txt b/epan/dissectors/CMakeLists.txt
index 00d8c3b4c9ed3377f17f3ce2824eda85b7d0fd66..efa8cd7f13006b1267b127caea2aa938942b1665 100644 (file)
--- a/epan/dissectors/CMakeLists.txt
+++ b/epan/dissectors/CMakeLists.txt
@@ -967,6 +967,7 @@ set(DISSECTOR_SRC
        ${CMAKE_CURRENT_SOURCE_DIR}/packet-etsi_card_app_toolkit.c
        ${CMAKE_CURRENT_SOURCE_DIR}/packet-etv.c
        ${CMAKE_CURRENT_SOURCE_DIR}/packet-evrc.c
+       ${CMAKE_CURRENT_SOURCE_DIR}/packet-exablaze.c
        ${CMAKE_CURRENT_SOURCE_DIR}/packet-exec.c
        ${CMAKE_CURRENT_SOURCE_DIR}/packet-exported_pdu.c
        ${CMAKE_CURRENT_SOURCE_DIR}/packet-extreme.c

diff --git a/epan/dissectors/packet-exablaze.c b/epan/dissectors/packet-exablaze.c
new file mode 100644 (file)
index 0000000..3a3126f
--- /dev/null
+++ b/epan/dissectors/packet-exablaze.c
@@ -0,0 +1,206 @@
+/* packet-exablaze.c
+ * Routines for dissection of Exablaze trailers
+ * Copyright 2018 Exablaze
+ *
+ * Wireshark - Network traffic analyzer
+ * By Gerald Combs <gerald@wireshark.org>
+ * Copyright 1998 Gerald Combs
+ *
+ * SPDX-License-Identifier: GPL-2.0-or-later
+ */
+
+#include "config.h"
+
+#include <math.h>
+
+#include <epan/packet.h>
+
+void proto_register_exablaze(void);
+void proto_reg_handoff_exablaze(void);
+
+static int proto_exablaze = -1;
+
+static int hf_exablaze_original_fcs = -1;
+static int hf_exablaze_device = -1;
+static int hf_exablaze_port = -1;
+static int hf_exablaze_timestamp = -1;
+static int hf_exablaze_timestamp_integer = -1;
+static int hf_exablaze_timestamp_fractional = -1;
+
+static gint ett_exablaze = -1;
+static gint ett_exablaze_timestamp = -1;
+
+static int
+dissect_exablaze(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree,
+        void *data _U_)
+{
+    proto_item *ti;
+    proto_tree *exablaze_tree;
+    proto_tree *timestamp_tree;
+
+    guint trailer_length;
+    guint fcs_length;
+    guint offset;
+    gboolean trailer_found;
+
+    guint8 device;
+    guint8 port;
+    guint32 timestamp_sec;
+    guint64 timestamp_frac;
+
+    nstime_t timestamp;
+    double timestamp_frac_double;
+    struct tm *tm;
+
+    trailer_length = tvb_reported_length(tvb);
+
+    if (trailer_length != tvb_captured_length(tvb)) {
+        /* The heuristics require the whole trailer to be captured */
+        return 0;
+    }
+
+    /* Try matching with and without FCS */
+    trailer_found = FALSE;
+    for (fcs_length = 0; fcs_length <= 4; fcs_length += 4)
+    {
+        if (trailer_length < fcs_length + 16)
+            continue;
+
+        offset = trailer_length - fcs_length - 16;
+
+        device = tvb_get_guint8(tvb, offset + 4);
+        port = tvb_get_guint8(tvb, offset + 5);
+        timestamp_sec = tvb_get_ntohl(tvb, offset + 6);
+        timestamp_frac = tvb_get_ntoh40(tvb, offset + 10);
+
+        /* If the capture time and timestamp differ by more than a week,
+         * then this is probably not a valid Exablaze trailer */
+        if (timestamp_sec > pinfo->abs_ts.secs) {
+            if (timestamp_sec - pinfo->abs_ts.secs > 604800)
+                continue;
+        } else {
+            if (pinfo->abs_ts.secs - timestamp_sec > 604800)
+                continue;
+        }
+
+        trailer_found = TRUE;
+        break;
+    }
+
+    if (!trailer_found)
+        return 0;
+
+    /* Fractional part is a 40 bit binary fraction of a second */
+    timestamp.secs = timestamp_sec;
+    timestamp_frac_double = ldexp((double)timestamp_frac, -40);
+    timestamp.nsecs = (int)(timestamp_frac_double * 1000000000);
+
+    ti = proto_tree_add_item(tree, proto_exablaze, tvb, offset, 16, ENC_NA);
+    proto_item_append_text(ti, ", Device: %u, Port: %u, Timestamp: ",
+            device, port);
+
+    tm = localtime(&timestamp.secs);
+    if (tm)
+        proto_item_append_text(ti, "%02u:%02u:%02.12f",
+                tm->tm_hour, tm->tm_min, tm->tm_sec + timestamp_frac_double);
+    else
+        proto_item_append_text(ti, "<Not representable>");
+
+    exablaze_tree = proto_item_add_subtree(ti, ett_exablaze);
+    proto_tree_add_item(exablaze_tree, hf_exablaze_original_fcs, tvb,
+            offset, 4, ENC_BIG_ENDIAN);
+    proto_tree_add_item(exablaze_tree, hf_exablaze_device, tvb,
+            offset + 4, 1, ENC_BIG_ENDIAN);
+    proto_tree_add_item(exablaze_tree, hf_exablaze_port, tvb,
+            offset + 5, 1, ENC_BIG_ENDIAN);
+
+    ti = proto_tree_add_time(exablaze_tree, hf_exablaze_timestamp, tvb,
+            offset + 6, 9, &timestamp);
+    timestamp_tree = proto_item_add_subtree(ti, ett_exablaze_timestamp);
+
+    proto_tree_add_item(timestamp_tree, hf_exablaze_timestamp_integer, tvb,
+            offset + 6, 4, ENC_BIG_ENDIAN);
+    proto_tree_add_double_format_value(timestamp_tree,
+            hf_exablaze_timestamp_fractional, tvb, offset + 10, 5,
+            timestamp_frac_double, "%.12f", timestamp_frac_double);
+
+    return offset + 16;
+}
+
+void
+proto_register_exablaze(void)
+{
+    static hf_register_info hf[] = {
+        {
+            &hf_exablaze_original_fcs,
+            {
+                "Original FCS", "exablaze.original_fcs",
+                FT_UINT32, BASE_HEX, NULL, 0x0, NULL, HFILL
+            }
+        },
+        {
+            &hf_exablaze_device,
+            {
+                "Device ID", "exablaze.device",
+                FT_UINT8, BASE_DEC, NULL, 0x0, NULL, HFILL
+            }
+        },
+        {
+            &hf_exablaze_port,
+            {
+                "Port", "exablaze.port",
+                FT_UINT8, BASE_DEC, NULL, 0x0, NULL, HFILL
+            }
+        },
+        {
+            &hf_exablaze_timestamp,
+            {
+                "Timestamp", "exablaze.timestamp",
+                FT_ABSOLUTE_TIME, ABSOLUTE_TIME_LOCAL, NULL, 0x0, NULL, HFILL
+            }
+        },
+        {   &hf_exablaze_timestamp_integer,
+            {
+                "Seconds since epoch", "exablaze.timestamp.seconds",
+                FT_UINT32, BASE_DEC, NULL, 0x0, NULL, HFILL
+            }
+        },
+        {   &hf_exablaze_timestamp_fractional,
+            {
+                "Fractional seconds",
+                "exablaze.timestamp.fractional_seconds",
+                FT_DOUBLE, BASE_NONE, NULL, 0x0, NULL, HFILL
+            }
+        }
+    };
+
+    static gint *ett[] = {
+        &ett_exablaze,
+        &ett_exablaze_timestamp
+    };
+
+    proto_exablaze = proto_register_protocol("Exablaze trailer", "Exablaze",
+            "exablaze");
+    proto_register_field_array(proto_exablaze, hf, array_length(hf));
+    proto_register_subtree_array(ett, array_length(ett));
+}
+
+void
+proto_reg_handoff_exablaze(void)
+{
+    heur_dissector_add("eth.trailer", dissect_exablaze, "Exablaze trailer",
+            "exablaze_eth", proto_exablaze, HEURISTIC_ENABLE);
+}
+
+/*
+ * Editor modelines  -  https://www.wireshark.org/tools/modelines.html
+ *
+ * Local variables:
+ * c-basic-offset: 4
+ * tab-width: 8
+ * indent-tabs-mode: nil
+ * End:
+ *
+ * vi: set shiftwidth=4 tabstop=8 expandtab:
+ * :indentSize=4:tabSize=8:noTabs=true:
+ */