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-rw-r--r--epan/dissectors/packet-2dparityfec.c272
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diff --git a/epan/dissectors/packet-2dparityfec.c b/epan/dissectors/packet-2dparityfec.c
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+/* packet-2dparityfec.c
+ * Mark Lewis <mlewis@altera.com>
+ *
+ * Wireshark - Network traffic analyzer
+ * By Gerald Combs <gerald@wireshark.org>
+ * Copyright 1998 Gerald Combs
+ *
+ * SPDX-License-Identifier: GPL-2.0-or-later
+ */
+
+/*
+** RTP Payload dissector for packets as specified in:
+** Pro-MPEG Code of Practice #3 release 2
+**
+** This protocol defines a format for FEC data embedded within RTP packets with
+** a payload type of 96 (0x60). The format of the FEC packets, which reside within
+** the RTP payload, is as follows...
+**
+** +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
+** | SNBase low bits | Length Recovery |
+** +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
+** |E| PT recovery | Mask |
+** +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
+** | TS recovery |
+** +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
+** |X|D|type |index| Offset | NA |SNBase ext bits|
+** +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
+** | |
+** : FEC Payload :
+** | |
+** +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
+**
+** For more information on this protocol see...
+** http://www.pro-mpeg.org/publications/pdf/Vid-on-IP-CoP3-r2.pdf
+**
+**
+** Notes:
+**
+** This protocol always resides in RTP packets with payload type 96. However,
+** type 96 is dynamic and may refer to other protocols. As Pro-MPEG FEC must
+** function in the absence of a control channel, and because this data is
+** likely to be transmitted within closed networks, no automatic mechanism
+** exists for specifying the existence of Pro-MPEG FEC on payload type 96.
+** This dissector is thus disabled by default. Dissection of this protocol
+** may be enabled from the 2dparityfec panel under Preferences->Protocols.
+**
+** Mark Lewis - 20th June 2006
+*/
+#include "config.h"
+
+#include <epan/packet.h>
+#include <epan/prefs.h>
+
+/* forward reference */
+void proto_register_2dparityfec(void);
+void proto_reg_handoff_2dparityfec(void);
+
+static dissector_handle_t handle_2dparityfec = NULL;
+
+static gboolean dissect_fec = FALSE;
+
+static int fec_rtp_payload_type = 96;
+
+static int proto_2dparityfec = -1;
+
+static int hf_2dparityfec_index = -1;
+static int hf_2dparityfec_length_recovery = -1;
+static int hf_2dparityfec_mask = -1;
+static int hf_2dparityfec_na = -1;
+static int hf_2dparityfec_offset = -1;
+static int hf_2dparityfec_payload = -1;
+static int hf_2dparityfec_pt_recovery = -1;
+static int hf_2dparityfec_rfc2733_ext = -1;
+static int hf_2dparityfec_row_flag = -1;
+static int hf_2dparityfec_snbase_ext = -1;
+static int hf_2dparityfec_snbase_low = -1;
+static int hf_2dparityfec_ts_pro_mpeg_ext = -1;
+static int hf_2dparityfec_ts_recovery = -1;
+static int hf_2dparityfec_type = -1;
+
+static gint ett_2dparityfec = -1;
+
+static const value_string fec_type_names[] = {
+ {0, "XOR"},
+ {1, "Hamming"},
+ {2, "Reed-Solomon"},
+ {0, NULL}
+};
+
+static int dissect_2dparityfec(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree, void* data _U_)
+{
+ guint8 OffsetField;
+ guint8 NAField;
+ guint32 SNBase;
+ guint8 D;
+
+ /* Extract SNBase */
+ SNBase = (guint32)tvb_get_guint8(tvb, 0)<<8;
+ SNBase |= (guint32)tvb_get_guint8(tvb, 1);
+ SNBase |= (guint32)tvb_get_guint8(tvb, 15)<<16;
+
+ /* Extract D */
+ D = (tvb_get_guint8(tvb, 12)>>6) & 0x1;
+
+ /* Extract Offset and NA */
+ OffsetField = tvb_get_guint8(tvb, 13);
+ NAField = tvb_get_guint8(tvb, 14);
+
+ col_set_str(pinfo->cinfo, COL_PROTOCOL, "2dFEC");
+
+ /* Configure the info column */
+ if(D)
+ {
+ col_add_fstr(pinfo->cinfo, COL_INFO, "Row FEC - SNBase=%u, Offset=%u, NA=%u",
+ SNBase, OffsetField, NAField);
+ }
+ else
+ {
+ col_add_fstr(pinfo->cinfo, COL_INFO, "Column FEC - SNBase=%u, Offset=%u, NA=%u",
+ SNBase, OffsetField, NAField);
+ }
+
+ if(tree)
+ {
+ /* we are being asked for details */
+ proto_item *ti;
+ proto_tree *tree_2dparityfec;
+ gint offset = 0;
+
+ ti = proto_tree_add_item(tree, proto_2dparityfec, tvb, 0, -1, ENC_NA);
+ tree_2dparityfec = proto_item_add_subtree(ti, ett_2dparityfec);
+
+ proto_tree_add_item(tree_2dparityfec, hf_2dparityfec_snbase_low, tvb, offset, 2, ENC_BIG_ENDIAN); offset += 2;
+ proto_tree_add_item(tree_2dparityfec, hf_2dparityfec_length_recovery, tvb, offset, 2, ENC_BIG_ENDIAN); offset += 2;
+ proto_tree_add_item(tree_2dparityfec, hf_2dparityfec_rfc2733_ext, tvb, offset, 1, ENC_BIG_ENDIAN);
+ proto_tree_add_item(tree_2dparityfec, hf_2dparityfec_pt_recovery, tvb, offset, 1, ENC_BIG_ENDIAN); offset += 1;
+ proto_tree_add_item(tree_2dparityfec, hf_2dparityfec_mask, tvb, offset, 3, ENC_BIG_ENDIAN); offset += 3;
+ proto_tree_add_item(tree_2dparityfec, hf_2dparityfec_ts_recovery, tvb, offset, 4, ENC_BIG_ENDIAN); offset += 4;
+ proto_tree_add_item(tree_2dparityfec, hf_2dparityfec_ts_pro_mpeg_ext, tvb, offset, 1, ENC_BIG_ENDIAN);
+ proto_tree_add_item(tree_2dparityfec, hf_2dparityfec_row_flag, tvb, offset, 1, ENC_BIG_ENDIAN);
+ proto_tree_add_item(tree_2dparityfec, hf_2dparityfec_type, tvb, offset, 1, ENC_BIG_ENDIAN);
+ proto_tree_add_item(tree_2dparityfec, hf_2dparityfec_index, tvb, offset, 1, ENC_BIG_ENDIAN); offset += 1;
+ proto_tree_add_item(tree_2dparityfec, hf_2dparityfec_offset, tvb, offset, 1, ENC_BIG_ENDIAN); offset += 1;
+ proto_tree_add_item(tree_2dparityfec, hf_2dparityfec_na, tvb, offset, 1, ENC_BIG_ENDIAN); offset += 1;
+ proto_tree_add_item(tree_2dparityfec, hf_2dparityfec_snbase_ext, tvb, offset, 1, ENC_BIG_ENDIAN); offset += 1;
+ proto_tree_add_item(tree_2dparityfec, hf_2dparityfec_payload, tvb, offset, -1, ENC_NA);
+ }
+
+ return tvb_captured_length(tvb);
+}
+
+void proto_register_2dparityfec(void)
+{
+ static hf_register_info hf[] = {
+ { &hf_2dparityfec_snbase_low,
+ { "SNBase low", "2dparityfec.snbase_low",
+ FT_UINT16, BASE_DEC, NULL, 0x0,
+ NULL, HFILL }
+ },
+ { &hf_2dparityfec_length_recovery,
+ { "Length recovery", "2dparityfec.lr",
+ FT_UINT16, BASE_HEX, NULL, 0x0,
+ NULL, HFILL }
+ },
+ { &hf_2dparityfec_rfc2733_ext,
+ { "RFC2733 Extension (E)", "2dparityfec.e",
+ FT_BOOLEAN, 8, NULL, 0x80,
+ NULL, HFILL }
+ },
+ { &hf_2dparityfec_pt_recovery,
+ { "Payload Type recovery", "2dparityfec.ptr",
+ FT_UINT8, BASE_HEX, NULL, 0x7f,
+ NULL, HFILL }
+ },
+ { &hf_2dparityfec_mask,
+ { "Mask", "2dparityfec.mask",
+ /*FT_UINT32*/FT_UINT24, BASE_HEX, NULL, /*0x00ffffff*/0x0,
+ NULL, HFILL }
+ },
+ { &hf_2dparityfec_ts_recovery,
+ { "Timestamp recovery", "2dparityfec.tsr",
+ FT_UINT32, BASE_HEX, NULL, 0x0,
+ NULL, HFILL }
+ },
+ { &hf_2dparityfec_ts_pro_mpeg_ext,
+ { "Pro-MPEG Extension (X)", "2dparityfec.x",
+ FT_BOOLEAN, 8, NULL, 0x80,
+ NULL, HFILL }
+ },
+ { &hf_2dparityfec_row_flag,
+ { "Row FEC (D)", "2dparityfec.d",
+ FT_BOOLEAN, 8, NULL, 0x40,
+ NULL, HFILL }
+ },
+ { &hf_2dparityfec_type,
+ { "Type", "2dparityfec.type",
+ FT_UINT8, BASE_DEC, VALS(fec_type_names), 0x38,
+ NULL, HFILL }
+ },
+ { &hf_2dparityfec_index,
+ { "Index", "2dparityfec.index",
+ FT_UINT8, BASE_DEC, NULL, 0x07,
+ NULL, HFILL }
+ },
+ { &hf_2dparityfec_offset,
+ { "Offset", "2dparityfec.offset",
+ FT_UINT8, BASE_DEC, NULL, 0x0,
+ NULL, HFILL }
+ },
+ { &hf_2dparityfec_na,
+ { "NA", "2dparityfec.na",
+ FT_UINT8, BASE_DEC, NULL, 0x0,
+ NULL, HFILL }
+ },
+ { &hf_2dparityfec_snbase_ext,
+ { "SNBase ext", "2dparityfec.snbase_ext",
+ FT_UINT8, BASE_DEC, NULL, 0x0,
+ NULL, HFILL }
+ },
+ { &hf_2dparityfec_payload,
+ { "FEC Payload", "2dparityfec.payload",
+ FT_BYTES, BASE_NONE, NULL, 0x0,
+ NULL, HFILL }
+ },
+ };
+
+/* Setup protocol subtree array */
+ static gint *ett[] = {
+ &ett_2dparityfec,
+ };
+
+ module_t *module_2dparityfec;
+
+ proto_2dparityfec = proto_register_protocol("Pro-MPEG Code of Practice #3 release 2 FEC Protocol", "2dparityfec", "2dparityfec");
+
+ proto_register_field_array(proto_2dparityfec, hf, array_length(hf));
+ proto_register_subtree_array(ett, array_length(ett));
+
+ module_2dparityfec = prefs_register_protocol(proto_2dparityfec,
+ proto_reg_handoff_2dparityfec);
+
+ prefs_register_bool_preference(module_2dparityfec, "enable",
+ "Decode Pro-MPEG FEC on RTP dynamic payload type 96",
+ "Enable this option to recognise all traffic on RTP dynamic payload type 96 (0x60) "
+ "as FEC data corresponding to Pro-MPEG Code of Practice #3 release 2",
+ &dissect_fec);
+
+ handle_2dparityfec = register_dissector("2dparityfec", dissect_2dparityfec,
+ proto_2dparityfec);
+}
+
+void proto_reg_handoff_2dparityfec(void)
+{
+ if (dissect_fec) {
+ dissector_add_uint("rtp.pt", fec_rtp_payload_type, handle_2dparityfec);
+ } else {
+ dissector_delete_uint("rtp.pt", fec_rtp_payload_type, handle_2dparityfec);
+ }
+}
+
+/*
+ * Editor modelines
+ *
+ * Local Variables:
+ * c-basic-offset: 3
+ * tab-width: 8
+ * indent-tabs-mode: nil
+ * End:
+ *
+ * ex: set shiftwidth=3 tabstop=8 expandtab:
+ * :indentSize=3:tabSize=8:noTabs=true:
+ */
generated by cgit v1.2.3 (git 2.39.1) at 2024-12-21 15:36:34 +0000