Adding upstream version 4.2.2.upstream/4.2.2

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 178 insertions, 0 deletions

diff --git a/epan/dissectors/packet-loop.c b/epan/dissectors/packet-loop.c
new file mode 100644
index 0000000..cba222e
--- /dev/null
+++ b/epan/dissectors/packet-loop.c
@@ -0,0 +1,178 @@
+/* packet-loop.c
+ * Routines for Ethernet loopback/Configuration Test Protocol dissection,
+ * as documented in section 8 "Ethernet Configuration Testing Protocol" of
+ * the v2.0 DIX Ethernet specification.
+ *
+ * See
+ *
+ *    http://decnet.ipv7.net/docs/dundas/aa-k759b-tk.pdf
+ *
+ * for a copy of the DIX spec and
+ *
+ *    http://stuff.mit.edu/people/jhawk/ctp.html
+ *
+ * for section 8.
+ *
+ * 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 <epan/packet.h>
+#include <epan/etypes.h>
+
+void proto_register_loop(void);
+void proto_reg_handoff_loop(void);
+
+static dissector_handle_t loop_handle;
+
+static int proto_loop = -1;
+static int hf_loop_skipcount = -1;
+static int hf_loop_function = -1;
+static int hf_loop_relevant_function = -1;
+static int hf_loop_receipt_number = -1;
+static int hf_loop_forwarding_address = -1;
+
+static gint ett_loop = -1;
+
+#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 int
+dissect_loop(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree, void* data _U_)
+{
+  proto_tree  *loop_tree = NULL;
+  proto_item  *ti;
+  guint16     function;
+  int         offset = 0;
+  int         skip_offset;
+  gboolean    set_info = TRUE;
+  gboolean    more_function;
+  tvbuff_t    *next_tvb;
+
+  col_set_str(pinfo->cinfo, COL_PROTOCOL, "LOOP");
+  col_clear(pinfo->cinfo, COL_INFO);
+
+  if (tree) {
+    ti = proto_tree_add_item(tree, proto_loop, tvb, offset, -1, ENC_NA);
+    loop_tree = proto_item_add_subtree(ti, ett_loop);
+
+    proto_tree_add_item(loop_tree, hf_loop_skipcount, tvb, offset, 2, ENC_LITTLE_ENDIAN);
+  }
+  skip_offset = 2 + tvb_get_letohs(tvb, offset);
+  offset += 2;
+
+  do {
+    function = tvb_get_letohs(tvb, offset);
+    if (offset == skip_offset) {
+      col_add_str(pinfo->cinfo, COL_INFO,
+                    val_to_str(function, function_vals, "Unknown function (%u)"));
+
+      proto_tree_add_uint(loop_tree, hf_loop_relevant_function, tvb, offset, 2, function);
+      set_info = FALSE;
+    }
+    proto_tree_add_uint(loop_tree, hf_loop_function, tvb, offset, 2, function);
+    offset += 2;
+    switch (function) {
+
+    case FUNC_REPLY:
+      proto_tree_add_item(loop_tree, hf_loop_receipt_number, tvb, offset, 2,
+                            ENC_LITTLE_ENDIAN);
+      offset += 2;
+      more_function = FALSE;
+      break;
+
+    case FUNC_FORWARD_DATA:
+      proto_tree_add_item(loop_tree, hf_loop_forwarding_address, tvb, offset,
+                            6, ENC_NA);
+      offset += 6;
+      more_function = TRUE;
+      break;
+
+    default:
+      more_function = FALSE;
+      break;
+    }
+  } while (more_function);
+
+  if (set_info) {
+    col_set_str(pinfo->cinfo, COL_INFO, "No valid function found");
+  }
+
+  if (tvb_reported_length_remaining(tvb, offset) > 0)
+  {
+    next_tvb = tvb_new_subset_remaining(tvb, offset);
+    call_data_dissector(next_tvb, pinfo, tree);
+  }
+  return tvb_captured_length(tvb);
+}
+
+void
+proto_register_loop(void)
+{
+  static hf_register_info hf[] = {
+    { &hf_loop_skipcount,
+      { "skipCount",            "loop.skipcount",
+    FT_UINT16,  BASE_DEC,       NULL,   0x0,
+      NULL, HFILL }},
+
+    { &hf_loop_function,
+      { "Function",             "loop.function",
+    FT_UINT16,  BASE_DEC,       VALS(function_vals),    0x0,
+      NULL, HFILL }},
+
+    { &hf_loop_relevant_function,
+      { "Relevant function",            "loop.relevant_function",
+    FT_UINT16,  BASE_DEC,       VALS(function_vals),    0x0,
+      NULL, HFILL }},
+
+    { &hf_loop_receipt_number,
+      { "Receipt number",       "loop.receipt_number",
+    FT_UINT16,  BASE_DEC,       NULL,   0x0,
+      NULL, HFILL }},
+
+    { &hf_loop_forwarding_address,
+      { "Forwarding address",   "loop.forwarding_address",
+    FT_ETHER,   BASE_NONE,      NULL,   0x0,
+      NULL, 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));
+
+  loop_handle = register_dissector("loop", dissect_loop, proto_loop);
+}
+
+void
+proto_reg_handoff_loop(void)
+{
+  dissector_add_uint("ethertype", ETHERTYPE_LOOP, loop_handle);
+}
+
+/*
+ * Editor modelines  -  https://www.wireshark.org/tools/modelines.html
+ *
+ * Local Variables:
+ * c-basic-offset: 2
+ * tab-width: 8
+ * indent-tabs-mode: nil
+ * End:
+ *
+ * ex: set shiftwidth=2 tabstop=8 expandtab:
+ * :indentSize=2:tabSize=8:noTabs=true:
+ */