/* packet-smpte-2110-20.c * SMPTE ST2110-20 * * Copyright 2023, Sergey V. Lobanov * * References: * SMPTE ST 2110-20:2022, Uncompressed Active Video * RFC4175, RTP Payload Format for Uncompressed Video * * Wireshark - Network traffic analyzer * By Gerald Combs * Copyright 1998 Gerald Combs * * SPDX-License-Identifier: GPL-2.0-or-later */ #include "config.h" #include #include #include #include #include "packet-rtp.h" void proto_reg_handoff_st2110_20(void); void proto_register_st2110_20(void); static dissector_handle_t st2110_20_handle; /* Initialize the protocol and registered fields */ static int proto_st2110_20 = -1; static int proto_rtp = -1; static int hf_st2110_ext_seqno = -1; static int hf_st2110_seqno = -1; static int hf_st2110_rtp_time = -1; static int hf_st2110_srd_index = -1; static int hf_st2110_srd_length = -1; static int hf_st2110_field_ident = -1; static int hf_st2110_row_num = -1; static int hf_st2110_continuation = -1; static int hf_st2110_srd_offset = -1; static int hf_st2110_srd_data = -1; static int hf_st2110_srd_rows = -1; /* Initialize the subtree pointers */ static gint ett_st2110_20 = -1; static gint ett_st2110_20_srd_row = -1; static int dissect_st2110_20(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree _U_, void* data _U_) { proto_item *item; proto_tree *st2110_20_tree; gint offset = 0; struct _rtp_packet_info *rtp_pkt_info = (struct _rtp_packet_info *)p_get_proto_data(wmem_file_scope(), pinfo, proto_rtp, RTP_CONVERSATION_PROTO_DATA); col_set_str(pinfo->cinfo, COL_PROTOCOL, "ST2110-20"); item = proto_tree_add_item(tree, proto_st2110_20, tvb, 0, -1, ENC_NA); st2110_20_tree = proto_item_add_subtree(item, ett_st2110_20); /* Extract original RTP sequence number from low bits */ guint32 rtp_seqno = (rtp_pkt_info != NULL) ? (rtp_pkt_info->extended_seqno & 0xFFFF) : 0; /* ST2110-20 extended sequence number field */ guint32 ext_seqno = tvb_get_guint16(tvb, offset, ENC_BIG_ENDIAN); /* Sequence number (RTP seqno is low bits, ST2110-20 ext seqno is high bits) */ guint32 seqno = (ext_seqno << 16) + rtp_seqno; /* Extract original RTP timestamp */ guint32 rtp_time = (rtp_pkt_info != NULL) ? (guint32)(rtp_pkt_info->extended_timestamp & 0xFFFFFFFF) : 0; proto_tree_add_item(st2110_20_tree, hf_st2110_ext_seqno, tvb, offset, 2, ENC_BIG_ENDIAN); PROTO_ITEM_SET_GENERATED( proto_tree_add_uint(st2110_20_tree, hf_st2110_seqno, tvb, offset, 2, seqno) ); PROTO_ITEM_SET_GENERATED( proto_tree_add_uint(st2110_20_tree, hf_st2110_rtp_time, NULL, 0, 0, rtp_time) ); offset += 2; /* st2110-20 ext seqno */ /* According to ST2110-20:2022 6.2.1, max three SRD headers might be in a packet */ guint16 srd_lengths[3] = {0, 0, 0}; /* store for second pass */ proto_tree* srd_header_trees[3] = {NULL, NULL, NULL}; /* store for second pass */ guint8 srd_rows = 0; /* rows count */ guint16 first_row; /* first row number */ for (guint8 srd_idx = 0; srd_idx < 3 ; srd_idx++) { proto_tree *srd_header_tree = proto_tree_add_subtree_format(st2110_20_tree, tvb, offset, 6, ett_st2110_20_srd_row, &item, "Sample Row Data %u", srd_idx); srd_header_trees[srd_idx] = srd_header_tree; PROTO_ITEM_SET_GENERATED( proto_tree_add_uint(srd_header_tree, hf_st2110_srd_index, NULL, 0, 0, srd_idx) ); srd_lengths[srd_idx] = tvb_get_guint16(tvb, offset, ENC_BIG_ENDIAN); proto_tree_add_item(srd_header_tree, hf_st2110_srd_length, tvb, offset, 2, ENC_BIG_ENDIAN); offset += 2; first_row = (srd_idx == 0) ? (tvb_get_guint16(tvb, offset, ENC_BIG_ENDIAN) & 0x7FFF) : first_row; proto_tree_add_item(srd_header_tree, hf_st2110_field_ident, tvb, offset, 2, ENC_BIG_ENDIAN); proto_tree_add_item(srd_header_tree, hf_st2110_row_num, tvb, offset, 2, ENC_BIG_ENDIAN); offset += 2; guint16 cont_bit = tvb_get_guint16(tvb, offset, ENC_BIG_ENDIAN) >> 15; proto_tree_add_item(srd_header_tree, hf_st2110_continuation, tvb, offset, 2, ENC_BIG_ENDIAN); proto_tree_add_item(srd_header_tree, hf_st2110_srd_offset, tvb, offset, 2, ENC_BIG_ENDIAN); offset += 2; srd_rows++; if (cont_bit != 1) /* if continuation is not set, then no more headers*/ break; } PROTO_ITEM_SET_GENERATED( proto_tree_add_uint(st2110_20_tree, hf_st2110_srd_rows, NULL, 0, 0, srd_rows) ); /* Second pass, get SRD data and add it to the same trees created for SRD headers */ for (guint8 srd_idx = 0; srd_idx < srd_rows ; srd_idx++) { guint16 srd_length = srd_lengths[srd_idx]; proto_tree_add_item(srd_header_trees[srd_idx], hf_st2110_srd_data, tvb, offset, srd_length, ENC_NA); offset += srd_length; } col_add_fstr(pinfo->cinfo, COL_INFO, "Seq=%u, Time=%u, FirstRow=%u, Rows=%u", seqno, rtp_time, first_row, srd_rows); return offset; } void proto_register_st2110_20(void) { module_t *st2110_20_module; static hf_register_info hf[] = { { &hf_st2110_ext_seqno, { "Extended Sequence Number", "st2110_20.ext_seq", FT_UINT16, BASE_DEC, NULL, 0x0, NULL, HFILL } }, { &hf_st2110_seqno, { "Sequence Number", "st2110_20.seq", FT_UINT16, BASE_DEC, NULL, 0x0, NULL, HFILL } }, { &hf_st2110_rtp_time, { "RTP Timestamp", "st2110_20.rtp_timestamp", FT_UINT32, BASE_DEC, NULL, 0x0, NULL, HFILL } }, { &hf_st2110_srd_index, { "SRD Header Index", "st2110_20.srd_index", FT_UINT8, BASE_DEC, NULL, 0x0, NULL, HFILL } }, { &hf_st2110_srd_length, { "SRD Length", "st2110_20.srd_length", FT_UINT16, BASE_DEC, NULL, 0x0, NULL, HFILL } }, { &hf_st2110_field_ident, { "Field Identification Bit", "st2110_20.srd_field_ident", FT_UINT16, BASE_DEC, NULL, 0x8000, NULL, HFILL } }, { &hf_st2110_row_num, { "SRD Row Number", "st2110_20.srd_row_num", FT_UINT16, BASE_DEC, NULL, 0x7FFF, NULL, HFILL } }, { &hf_st2110_continuation, { "SRD Continuation Bit", "st2110_20.srd_cont_bit", FT_UINT16, BASE_DEC, NULL, 0x8000, NULL, HFILL } }, { &hf_st2110_srd_offset, { "SRD Offset", "st2110_20.srd_offset", FT_UINT16, BASE_DEC, NULL, 0x7FFF, NULL, HFILL } }, { &hf_st2110_srd_data, { "SRD Data", "st2110_20.srd_data", FT_NONE, BASE_NONE, NULL, 0x0, NULL, HFILL } }, { &hf_st2110_srd_rows, { "SRD Rows", "st2110_20.srd_rows", FT_UINT8, BASE_DEC, NULL, 0x0, NULL, HFILL } } }; static gint *ett[] = { &ett_st2110_20, &ett_st2110_20_srd_row }; proto_st2110_20 = proto_register_protocol("SMPTE ST2110-20 (Uncompressed Active Video)", "ST2110-20", "st2110_20"); proto_register_field_array(proto_st2110_20, hf, array_length(hf)); proto_register_subtree_array(ett, array_length(ett)); st2110_20_module = prefs_register_protocol(proto_st2110_20, NULL); prefs_register_obsolete_preference(st2110_20_module, "dynamic.payload.type"); st2110_20_handle = register_dissector("st2110_20", dissect_st2110_20, proto_st2110_20); } void proto_reg_handoff_st2110_20(void) { dissector_add_string("rtp_dyn_payload_type" , "ST2110-20", st2110_20_handle); dissector_add_uint_range_with_preference("rtp.pt", "", st2110_20_handle); proto_rtp = proto_get_id_by_filter_name("rtp"); } /* * 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: */