epan/dissectors/packet-alp.c

   1 /* packet-alp.c
   2  * Routines for ALP dissection
   3  * Copyright 2020, Nick Kelsey <nickk@silicondust.com>
   4  *
   5  * Wireshark - Network traffic analyzer
   6  * By Gerald Combs <gerald@wireshark.org>
   7  * Copyright 1998 Gerald Combs
   8  *
   9  * SPDX-License-Identifier: GPL-2.0-or-later
  10  */
  11
  12 /*
  13  * ATSC Link-Layer Protocol (A/330)
  14  * https://www.atsc.org/atsc-30-standard/a3302016-link-layer-protocol/
  15  */
  16
  17 #include <config.h>
  18 #include <epan/packet.h>
  19 #include <epan/to_str.h>
  20 #include <epan/unit_strings.h>
  21 #include <wsutil/array.h>
  22 #include <wiretap/wtap.h>
  23
  24 void proto_reg_handoff_alp(void);
  25 void proto_register_alp(void);
  26
  27 static int proto_alp;
  28 static int ett_alp;
  29 static int ett_alp_si;
  30 static int ett_alp_he;
  31 static int ett_alp_sig_info;
  32 static int ett_alp_lmt;
  33 static int ett_alp_lmt_plp;
  34 static int ett_alp_lmt_plp_mc;
  35
  36 static dissector_handle_t alp_handle;
  37 static dissector_handle_t ip_handle;
  38 static dissector_handle_t ts_handle;
  39
  40 static int hf_alp_packet_type;
  41 #define ALP_PACKET_TYPE_MASK 0xE0
  42 #define ALP_PACKET_TYPE_IPV4 0
  43 #define ALP_PACKET_TYPE_SIGNALLING 4
  44 #define ALP_PACKET_TYPE_MPEG_TS 7
  45 static const value_string alp_packet_type_vals[] = {
  46     { 0, "IPv4 packet" },
  47     { 1, "Reserved" },
  48     { 2, "Compressed IPv4 packet" },
  49     { 3, "Reserved" },
  50     { 4, "Link layer signalling packet" },
  51     { 5, "Reserved" },
  52     { 6, "Packet type extension" },
  53     { 7, "MPEG-2 transport stream" },
  54     { 0, NULL }
  55 };
  56
  57 static int hf_alp_mpegts_numts;
  58 static int hf_alp_mpegts_ahf;
  59 static int hf_alp_mpegts_hdm;
  60 static int hf_alp_mpegts_dnp;
  61 #define ALP_MPEGTS_NUMTS_MASK 0x1E
  62 #define ALP_MPEGTS_AHF_MASK 0x01
  63 #define ALP_MPEGTS_HDM_MASK 0x80
  64 #define ALP_MPEGTS_DNP_MASK 0x7F
  65
  66 static int hf_alp_payload_configuration;
  67 static int hf_alp_header_mode;
  68 static int hf_alp_segmentation_concatenation;
  69 #define ALP_PAYLOAD_CONFIGURATION_MASK 0x10
  70 #define ALP_HEADER_MODE_MASK 0x08
  71 #define ALP_SEGMENTATION_CONCATENATION_MASK 0x08
  72 static const value_string alp_segmentation_concatenation_vals[] = {
  73     { 0, "Packet segment" },
  74     { 1, "Concatenated packets" },
  75     { 0, NULL }
  76 };
  77
  78 static int hf_alp_length;
  79 #define ALP_LENGTH_MASK 0x07FF
  80
  81 static int hf_alp_single_length;
  82 static int hf_alp_single_sif;
  83 static int hf_alp_single_hef;
  84 #define ALP_SINGLE_LENGTH_MASK 0x07FFF8
  85 #define ALP_SINGLE_SIF_MASK 0x02
  86 #define ALP_SINGLE_HEF_MASK 0x01
  87
  88 static int hf_alp_segment_sequence_number;
  89 static int hf_alp_segment_last_indicator;
  90 static int hf_alp_segment_sif;
  91 static int hf_alp_segment_hef;
  92 #define ALP_SEGMENT_SEQUENCE_NUMBER_MASK 0xF8
  93 #define ALP_SEGMENT_LAST_INDICATOR_MASK 0x04
  94 #define ALP_SEGMENT_SIF_MASK 0x02
  95 #define ALP_SEGMENT_HEF_MASK 0x01
  96
  97 static int hf_alp_concat_length;
  98 static int hf_alp_concat_count;
  99 static int hf_alp_concat_sif;
 100 #define ALP_CONCAT_LENGTH_MASK 0x07FFF0
 101 #define ALP_CONCAT_COUNT_MASK 0x0E
 102 #define ALP_CONCAT_SIF_MASK 0x01
 103
 104 static int hf_alp_si;
 105 static int hf_alp_sid;
 106
 107 static int hf_alp_header_extension;
 108 static int hf_alp_header_extension_type;
 109 static int hf_alp_header_extension_length;
 110
 111 static int hf_alp_header_extension_sony_l1d_timeinfo;
 112 static int hf_alp_header_extension_sony_l1d_timeinfo_flag;
 113 static int hf_alp_header_extension_sony_l1d_timeinfo_sec;
 114 static int hf_alp_header_extension_sony_l1d_timeinfo_ms;
 115 static int hf_alp_header_extension_sony_l1d_timeinfo_us;
 116 static int hf_alp_header_extension_sony_l1d_timeinfo_ns;
 117 static int hf_alp_header_extension_sony_l1d_timeinfo_time;
 118 static int hf_alp_header_extension_sony_l1d_timeinfo_time_ns;
 119 static int hf_alp_header_extension_sony_plp_id;
 120 static int hf_alp_header_extension_sony_plp_unk;
 121 #define ALP_HE_SONY_L1D_TIME_FLAG_MASK 0xC000000000000000
 122 #define ALP_HE_SONY_L1D_TIME_SEC_MASK  0x3FFFFFFFC0000000
 123 #define ALP_HE_SONY_L1D_TIME_MS_MASK   0x000000003FF00000
 124 #define ALP_HE_SONY_L1D_TIME_US_MASK   0x00000000000FFC00
 125 #define ALP_HE_SONY_L1D_TIME_NS_MASK   0x00000000000003FF
 126 #define ALP_HE_SONY_PLP_NUM_MASK 0xFC
 127 #define ALP_HE_SONY_PLP_UNK_MASK 0x03
 128
 129 static int hf_alp_sig_info;
 130 static int hf_alp_sig_info_type;
 131 static int hf_alp_sig_info_type_extension;
 132 static int hf_alp_sig_info_version;
 133 static int hf_alp_sig_info_format;
 134 static int hf_alp_sig_info_encoding;
 135 #define ALP_SIG_INFO_FORMAT_MASK 0xC0
 136 #define ALP_SIG_INFO_ENCODING_MASK 0x30
 137 #define ALP_SIG_INFO_TYPE_LMT 0x01
 138 static const value_string alp_sig_info_type_vals[] = {
 139     { 0x01, "Link Mapping Table" },
 140     { 0x02, "ROHC-U Description Table" },
 141     { 0, NULL }
 142 };
 143 static const value_string alp_sig_info_format_vals[] = {
 144     { 0, "Binary" },
 145     { 1, "XML" },
 146     { 2, "JSON" },
 147     { 3, "Reserved" },
 148     { 0, NULL }
 149 };
 150 static const value_string alp_sig_info_encoding_vals[] = {
 151     { 0, "No Compression" },
 152     { 1, "DEFLATE" },
 153     { 2, "Reserved" },
 154     { 3, "Reserved" },
 155     { 0, NULL }
 156 };
 157
 158 static int hf_alp_lmt;
 159 static int hf_alp_lmt_numplp;
 160 static int hf_alp_lmt_reserved;
 161 static int hf_alp_lmt_plp;
 162 static int hf_alp_lmt_plp_id;
 163 static int hf_alp_lmt_plp_reserved;
 164 static int hf_alp_lmt_plp_nummc;
 165 static int hf_alp_lmt_plp_mc;
 166 static int hf_alp_lmt_plp_mc_src_ip;
 167 static int hf_alp_lmt_plp_mc_dst_ip;
 168 static int hf_alp_lmt_plp_mc_src_port;
 169 static int hf_alp_lmt_plp_mc_dst_port;
 170 static int hf_alp_lmt_plp_mc_sid_flag;
 171 static int hf_alp_lmt_plp_mc_comp_flag;
 172 static int hf_alp_lmt_plp_mc_reserved;
 173 static int hf_alp_lmt_plp_mc_sid;
 174 static int hf_alp_lmt_plp_mc_context_id;
 175
 176 #define ALP_LMT_NUMPLP_MASK 0xFC
 177 #define ALP_LMT_RESERVED_MASK 0x03
 178 #define ALP_LMT_PLP_ID_MASK 0xFC
 179 #define ALP_LMT_PLP_RESERVED_MASK 0x03
 180 #define ALP_LMT_PLP_MC_SID_MASK 0x80
 181 #define ALP_LMT_PLP_MC_COMP_MASK 0x40
 182 #define ALP_LMT_PLP_MC_RESERVED_MASK 0x3F
 183
 184 static int hf_alp_junk;
 185
 186 static int
 187 dissect_alp_mpegts(tvbuff_t *tvb, int offset, packet_info *pinfo, proto_tree *tree, proto_tree *alp_tree)
 188 {
 189     uint8_t header0 = tvb_get_uint8(tvb, offset);
 190     uint8_t ahf = header0 & ALP_MPEGTS_AHF_MASK;
 191     uint8_t numts = (header0 & ALP_MPEGTS_NUMTS_MASK) >> 1;
 192     if (numts == 0) {
 193         numts = 16;
 194     }
 195
 196     PROTO_ITEM_SET_GENERATED(
 197         proto_tree_add_uint(alp_tree, hf_alp_mpegts_numts, tvb, offset, 1, numts)
 198     );
 199     proto_tree_add_item(alp_tree, hf_alp_mpegts_ahf, tvb, offset, 1, ENC_BIG_ENDIAN);
 200     offset++;
 201
 202     uint8_t hdm = 0;
 203     uint8_t dnp = 0;
 204
 205     if (ahf) {
 206         uint8_t header1 = tvb_get_uint8(tvb, offset);
 207         hdm = header1 & ALP_MPEGTS_HDM_MASK;
 208         dnp = header1 & ALP_MPEGTS_DNP_MASK;
 209         if ((hdm == 0) && (dnp == 0)) {
 210             dnp = 128;
 211         }
 212
 213         proto_tree_add_item(alp_tree, hf_alp_mpegts_hdm, tvb, offset, 1, ENC_BIG_ENDIAN);
 214         PROTO_ITEM_SET_GENERATED(
 215             proto_tree_add_uint(alp_tree, hf_alp_mpegts_dnp, tvb, offset, 1, dnp)
 216         );
 217         offset++;
 218     }
 219
 220     while (dnp--) {
 221         unsigned char *ts_frame = (unsigned char*)wmem_alloc(pinfo->pool, 188);
 222
 223         ts_frame[0] = 0x47;
 224         ts_frame[1] = 0x1F;
 225         ts_frame[2] = 0xFF;
 226         ts_frame[3] = 0x10;
 227         ts_frame[4] = 0x00;
 228         memset(ts_frame + 5, 0xFF, 183);
 229
 230         tvbuff_t *ts_frame_tvb = tvb_new_child_real_data(tvb, ts_frame, 188, 188);
 231         call_dissector(ts_handle, ts_frame_tvb, pinfo, tree);
 232     }
 233
 234     unsigned char *ts_frame = (unsigned char*)wmem_alloc(pinfo->pool, 188);
 235
 236     ts_frame[0] = 0x47;
 237     tvb_memcpy(tvb, ts_frame + 1, offset, 187);
 238     offset += 187;
 239
 240     unsigned char header[4];
 241     memcpy(header, ts_frame, 4);
 242
 243     tvbuff_t *ts_frame_tvb = tvb_new_child_real_data(tvb, ts_frame, 188, 188);
 244     call_dissector(ts_handle, ts_frame_tvb, pinfo, tree);
 245
 246     while (--numts) {
 247         ts_frame = (unsigned char*)wmem_alloc(pinfo->pool, 188);
 248
 249         if (hdm) {
 250             header[3] = (header[3] & 0xF0) | ((header[3] + 1) & 0x0F);
 251             memcpy(ts_frame, header, 4);
 252             tvb_memcpy(tvb, ts_frame + 4, offset, 184);
 253             offset += 184;
 254         } else {
 255             ts_frame[0] = 0x47;
 256             tvb_memcpy(tvb, ts_frame + 1, offset, 187);
 257             offset += 187;
 258         }
 259
 260         ts_frame_tvb = tvb_new_child_real_data(tvb, ts_frame, 188, 188);
 261         call_dissector(ts_handle, ts_frame_tvb, pinfo, tree);
 262     }
 263
 264     if (offset < (int)tvb_captured_length(tvb)) {
 265         int junk_length = tvb_captured_length(tvb) - offset;
 266         proto_tree_add_bytes_format(alp_tree, hf_alp_junk, tvb, offset, -1, NULL, "Junk at end (%u byte%s)", junk_length, (junk_length == 1) ? "" : "s");
 267     }
 268
 269     return tvb_captured_length(tvb);
 270 }
 271
 272 static int
 273 dissect_alp(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree, void *data _U_)
 274 {
 275     col_set_str(pinfo->cinfo, COL_PROTOCOL, "ALP");
 276     col_clear(pinfo->cinfo, COL_INFO);
 277
 278     proto_item *ti = proto_tree_add_item(tree, proto_alp, tvb, 0, -1, ENC_NA);
 279     proto_tree *alp_tree = proto_item_add_subtree(ti, ett_alp);
 280
 281     int offset = 0;
 282     uint8_t packet_type = tvb_get_uint8(tvb, offset) >> 5;
 283     proto_tree_add_item(alp_tree, hf_alp_packet_type, tvb, offset, 1, ENC_BIG_ENDIAN);
 284
 285     if (packet_type == ALP_PACKET_TYPE_MPEG_TS) {
 286         return dissect_alp_mpegts(tvb, offset, pinfo, tree, alp_tree);
 287     }
 288
 289     bool payload_configuration = (tvb_get_uint8(tvb, offset) & ALP_PAYLOAD_CONFIGURATION_MASK) != 0;
 290     proto_tree_add_item(alp_tree, hf_alp_payload_configuration, tvb, offset, 1, ENC_BIG_ENDIAN);
 291
 292     bool sif = false;
 293     bool hef = false;
 294     uint16_t payload_length = 0;
 295
 296     if (payload_configuration == 0) {
 297         bool header_mode = (tvb_get_uint8(tvb, offset) & ALP_HEADER_MODE_MASK) != 0;
 298         proto_tree_add_item(alp_tree, hf_alp_header_mode, tvb, offset, 1, ENC_BIG_ENDIAN);
 299
 300         if (header_mode == 0) {
 301             payload_length = tvb_get_uint16(tvb, offset, ENC_BIG_ENDIAN) & ALP_LENGTH_MASK;
 302             proto_tree_add_item(alp_tree, hf_alp_length, tvb, offset, 2, ENC_BIG_ENDIAN);
 303             offset += 2;
 304         } else {
 305             payload_length = (tvb_get_uint24(tvb, offset, ENC_BIG_ENDIAN) & ALP_SINGLE_LENGTH_MASK) >> 3;
 306             proto_tree_add_item(alp_tree, hf_alp_single_length, tvb, offset, 3, ENC_BIG_ENDIAN);
 307             offset += 2;
 308
 309             sif = (tvb_get_uint8(tvb, offset) & ALP_SINGLE_SIF_MASK) != 0;
 310             hef = (tvb_get_uint8(tvb, offset) & ALP_SINGLE_HEF_MASK) != 0;
 311             proto_tree_add_item(alp_tree, hf_alp_single_sif, tvb, offset, 1, ENC_BIG_ENDIAN);
 312             proto_tree_add_item(alp_tree, hf_alp_single_hef, tvb, offset, 1, ENC_BIG_ENDIAN);
 313             offset++;
 314         }
 315     } else {
 316         bool segmentation_concatenation = (tvb_get_uint8(tvb, offset) & ALP_SEGMENTATION_CONCATENATION_MASK) != 0;
 317         proto_tree_add_item(alp_tree, hf_alp_segmentation_concatenation, tvb, offset, 1, ENC_BIG_ENDIAN);
 318
 319         if (segmentation_concatenation == 0) {
 320             payload_length = tvb_get_uint16(tvb, offset, ENC_BIG_ENDIAN) & ALP_LENGTH_MASK;
 321             proto_tree_add_item(alp_tree, hf_alp_length, tvb, offset, 2, ENC_BIG_ENDIAN);
 322             offset += 2;
 323
 324             sif = (tvb_get_uint8(tvb, offset) & ALP_SEGMENT_SIF_MASK) != 0;
 325             hef = (tvb_get_uint8(tvb, offset) & ALP_SEGMENT_HEF_MASK) != 0;
 326             proto_tree_add_item(alp_tree, hf_alp_segment_sequence_number, tvb, offset, 1, ENC_BIG_ENDIAN);
 327             proto_tree_add_item(alp_tree, hf_alp_segment_last_indicator, tvb, offset, 1, ENC_BIG_ENDIAN);
 328             proto_tree_add_item(alp_tree, hf_alp_segment_sif, tvb, offset, 1, ENC_BIG_ENDIAN);
 329             proto_tree_add_item(alp_tree, hf_alp_segment_hef, tvb, offset, 1, ENC_BIG_ENDIAN);
 330             offset++;
 331         } else {
 332             payload_length = (tvb_get_uint24(tvb, offset, ENC_BIG_ENDIAN) & ALP_CONCAT_LENGTH_MASK) >> 4;
 333             proto_tree_add_item(alp_tree, hf_alp_concat_length, tvb, offset, 3, ENC_BIG_ENDIAN);
 334             offset += 2;
 335
 336             uint8_t count = (tvb_get_uint8(tvb, offset) & ALP_CONCAT_COUNT_MASK) >> 1;
 337             sif = (tvb_get_uint8(tvb, offset) & ALP_CONCAT_SIF_MASK) != 0;
 338             proto_tree_add_item(alp_tree, hf_alp_concat_count, tvb, offset, 1, ENC_BIG_ENDIAN);
 339             proto_tree_add_item(alp_tree, hf_alp_concat_sif, tvb, offset, 1, ENC_BIG_ENDIAN);
 340             offset++;
 341
 342             uint32_t skip = (uint32_t)count * 12;
 343             if (count & 0x01) {
 344                 skip += 4;
 345            }
 346            offset += skip / 8;
 347         }
 348     }
 349
 350     if (sif) {
 351         proto_item *si_item = proto_tree_add_item(alp_tree, hf_alp_si, tvb, offset, 1, ENC_NA);
 352         proto_tree *si_tree = proto_item_add_subtree(si_item, ett_alp_si);
 353
 354         proto_tree_add_item(si_tree, hf_alp_sid, tvb, offset, 1, ENC_BIG_ENDIAN);
 355         offset++;
 356     }
 357
 358     if (hef) {
 359         uint8_t he_length_m1 = tvb_get_uint8(tvb, offset + 1);
 360         uint16_t he_length = (uint16_t)he_length_m1 + 1;
 361         proto_item *he_item = proto_tree_add_item(alp_tree, hf_alp_header_extension, tvb, offset, 2 + he_length, ENC_NA);
 362         proto_tree *he_tree = proto_item_add_subtree(he_item, ett_alp_he);
 363
 364         uint8_t he_type = tvb_get_uint8(tvb, offset);
 365
 366         proto_tree_add_item(he_tree, hf_alp_header_extension_type, tvb, offset, 1, ENC_BIG_ENDIAN);
 367         offset++;
 368
 369         PROTO_ITEM_SET_GENERATED(
 370             proto_tree_add_uint(he_tree, hf_alp_header_extension_length, tvb, offset, 1, he_length)
 371         );
 372         offset++;
 373
 374         if (he_type == 0xF0 && he_length == 8) {
 375             /* Sony L1D Time Info Extension */
 376             uint64_t sony_time = tvb_get_uint64(tvb, offset, ENC_BIG_ENDIAN);
 377             uint64_t sony_sec = (sony_time & ALP_HE_SONY_L1D_TIME_SEC_MASK) >> 30;
 378             uint64_t sony_ms = (sony_time & ALP_HE_SONY_L1D_TIME_MS_MASK) >> 20;
 379             uint64_t sony_us = (sony_time & ALP_HE_SONY_L1D_TIME_US_MASK) >> 10;
 380             uint64_t sony_ns = sony_time & ALP_HE_SONY_L1D_TIME_NS_MASK;
 381             uint64_t ns_part = sony_ns + sony_us * 1000 + sony_ms * 1000000;
 382             uint64_t ns_full = ns_part + sony_sec * 1000000000;
 383             nstime_t abs_time = {
 384                 .secs = (time_t) sony_sec,
 385                 .nsecs = (int) ns_part
 386             };
 387             col_add_fstr(pinfo->cinfo, COL_INFO, "Sony L1D TAI Time: %s (%" PRIu64 ")",
 388                 abs_time_to_str(pinfo->pool, &abs_time, ABSOLUTE_TIME_UTC, false), ns_full);
 389
 390             proto_tree_add_item(he_tree, hf_alp_header_extension_sony_l1d_timeinfo, tvb, offset, 8, ENC_BIG_ENDIAN);
 391             proto_tree_add_item(he_tree, hf_alp_header_extension_sony_l1d_timeinfo_flag, tvb, offset, 8, ENC_BIG_ENDIAN);
 392             proto_tree_add_item(he_tree, hf_alp_header_extension_sony_l1d_timeinfo_sec, tvb, offset, 8, ENC_BIG_ENDIAN);
 393             proto_tree_add_item(he_tree, hf_alp_header_extension_sony_l1d_timeinfo_ms, tvb, offset, 8, ENC_BIG_ENDIAN);
 394             proto_tree_add_item(he_tree, hf_alp_header_extension_sony_l1d_timeinfo_us, tvb, offset, 8, ENC_BIG_ENDIAN);
 395             proto_tree_add_item(he_tree, hf_alp_header_extension_sony_l1d_timeinfo_ns, tvb, offset, 8, ENC_BIG_ENDIAN);
 396             PROTO_ITEM_SET_GENERATED(
 397                 proto_tree_add_time(he_tree, hf_alp_header_extension_sony_l1d_timeinfo_time, tvb, offset, 8, &abs_time)
 398             );
 399             PROTO_ITEM_SET_GENERATED(
 400                 proto_tree_add_uint64(he_tree, hf_alp_header_extension_sony_l1d_timeinfo_time_ns, tvb, offset, 8, ns_full)
 401             );
 402             offset += 8;
 403         } else if (he_type == 0xF1 && he_length == 1) {
 404             /* Sony PLP Extension */
 405             col_add_fstr(pinfo->cinfo, COL_INFO, "Sony PLP Extension: PLP %u", (tvb_get_uint8(tvb, offset) & ALP_HE_SONY_PLP_NUM_MASK) >> 2);
 406             proto_tree_add_item(he_tree, hf_alp_header_extension_sony_plp_id, tvb, offset, 1, ENC_BIG_ENDIAN);
 407             proto_tree_add_item(he_tree, hf_alp_header_extension_sony_plp_unk, tvb, offset, 1, ENC_BIG_ENDIAN);
 408             offset++;
 409         } else {
 410             tvbuff_t *he_data_tvb = tvb_new_subset_length(tvb, offset, he_length);
 411             call_data_dissector(he_data_tvb, pinfo, he_tree);
 412             offset += he_length;
 413         }
 414     }
 415
 416     if (packet_type == ALP_PACKET_TYPE_SIGNALLING) {
 417         proto_item *sig_info_item = proto_tree_add_item(alp_tree, hf_alp_sig_info, tvb, offset, 5, ENC_NA);
 418         proto_tree *sig_info_tree = proto_item_add_subtree(sig_info_item, ett_alp_sig_info);
 419
 420         uint8_t sig_info_type = tvb_get_uint8(tvb, offset);
 421         proto_tree_add_item(sig_info_tree, hf_alp_sig_info_type, tvb, offset, 1, ENC_BIG_ENDIAN);
 422         offset++;
 423
 424         proto_tree_add_item(sig_info_tree, hf_alp_sig_info_type_extension, tvb, offset, 2, ENC_BIG_ENDIAN);
 425         offset += 2;
 426
 427         proto_tree_add_item(sig_info_tree, hf_alp_sig_info_version, tvb, offset, 1, ENC_BIG_ENDIAN);
 428         offset++;
 429
 430         proto_tree_add_item(sig_info_tree, hf_alp_sig_info_format, tvb, offset, 1, ENC_BIG_ENDIAN);
 431         proto_tree_add_item(sig_info_tree, hf_alp_sig_info_encoding, tvb, offset, 1, ENC_BIG_ENDIAN);
 432         offset++;
 433
 434         if (sig_info_type == ALP_SIG_INFO_TYPE_LMT) {
 435             proto_item *lmt_item = proto_tree_add_item(alp_tree, hf_alp_lmt, tvb, offset, payload_length, ENC_NA);
 436             proto_tree *lmt_tree = proto_item_add_subtree(lmt_item, ett_alp_lmt);
 437
 438             uint8_t lmt_numplp = ((tvb_get_uint8(tvb, offset) & ALP_LMT_NUMPLP_MASK) >> 2) + 1;
 439             col_add_fstr(pinfo->cinfo, COL_INFO, "Link Mapping Table, number of PLPs: %u", lmt_numplp);
 440             PROTO_ITEM_SET_GENERATED(
 441                 proto_tree_add_uint(lmt_tree, hf_alp_lmt_numplp, tvb, offset, 1, lmt_numplp)
 442             );
 443             proto_tree_add_item(lmt_tree, hf_alp_lmt_reserved, tvb, offset, 1, ENC_BIG_ENDIAN);
 444             offset++;
 445
 446             for(uint8_t i = 0; i < lmt_numplp; i++) {
 447                 /* Fist pass. Calculate PLP entry length */
 448                 int lmt_plp_length = 2;
 449                 uint8_t lmt_mc_nummc = tvb_get_uint8(tvb, offset + 1);
 450                 int plp_mc_len = 0;
 451                 for(uint8_t j = 0; j < lmt_mc_nummc; j++) {
 452                     uint8_t lmt_mc_plp_flags = tvb_get_uint8(tvb, offset + 2 + plp_mc_len + 12);
 453                     plp_mc_len += 13;
 454                     uint8_t lmt_mc_plp_sid_flag = lmt_mc_plp_flags & ALP_LMT_PLP_MC_SID_MASK;
 455                     uint8_t lmt_mc_plp_comp_flag = lmt_mc_plp_flags & ALP_LMT_PLP_MC_COMP_MASK;
 456                     if (lmt_mc_plp_sid_flag) {
 457                         plp_mc_len += 1;
 458                     }
 459                     if (lmt_mc_plp_comp_flag) {
 460                         plp_mc_len += 1;
 461                     }
 462                 }
 463                 lmt_plp_length += plp_mc_len;
 464
 465                 /* Second pass. Add PLP to the tree */
 466                 proto_item *lmt_plp_item = proto_tree_add_item(lmt_tree, hf_alp_lmt_plp, tvb, offset, lmt_plp_length, ENC_NA);
 467                 proto_tree *lmt_plp_tree = proto_item_add_subtree(lmt_plp_item, ett_alp_lmt_plp);
 468
 469                 uint8_t lmt_plp_id = (tvb_get_uint8(tvb, offset) & ALP_LMT_PLP_ID_MASK) >> 2;
 470                 proto_item_append_text(lmt_plp_item, " ID=%u", lmt_plp_id);
 471
 472                 proto_tree_add_item(lmt_plp_tree, hf_alp_lmt_plp_id, tvb, offset, 1, ENC_BIG_ENDIAN);
 473                 proto_tree_add_item(lmt_plp_tree, hf_alp_lmt_plp_reserved, tvb, offset, 1, ENC_BIG_ENDIAN);
 474                 offset++;
 475
 476                 proto_tree_add_item(lmt_plp_tree, hf_alp_lmt_plp_nummc, tvb, offset, 1, ENC_BIG_ENDIAN);
 477                 offset++;
 478
 479                 for(uint8_t j = 0; j < lmt_mc_nummc; j++) {
 480                     int mc_len = 13;
 481                     uint8_t lmt_mc_plp_flags = tvb_get_uint8(tvb, offset + 12);
 482                     uint8_t lmt_mc_plp_sid_flag = lmt_mc_plp_flags & ALP_LMT_PLP_MC_SID_MASK;
 483                     uint8_t lmt_mc_plp_comp_flag = lmt_mc_plp_flags & ALP_LMT_PLP_MC_COMP_MASK;
 484                     if (lmt_mc_plp_sid_flag) {
 485                         mc_len += 1;
 486                     }
 487                     if (lmt_mc_plp_comp_flag) {
 488                         mc_len += 1;
 489                     }
 490
 491                     proto_item *lmt_plp_mc_item = proto_tree_add_item(lmt_plp_tree, hf_alp_lmt_plp_mc, tvb, offset, mc_len, ENC_NA);
 492                     proto_item_append_text(lmt_plp_mc_item, " (%u) Dst=%s:%u", j, tvb_ip_to_str(pinfo->pool, tvb, offset + 4), tvb_get_uint16(tvb, offset + 10, ENC_BIG_ENDIAN));
 493                     proto_tree *lmt_plp_mc_tree = proto_item_add_subtree(lmt_plp_mc_item, ett_alp_lmt_plp_mc);
 494
 495                     proto_tree_add_item(lmt_plp_mc_tree, hf_alp_lmt_plp_mc_src_ip, tvb, offset, 4, ENC_BIG_ENDIAN);
 496                     offset += 4;
 497
 498                     proto_tree_add_item(lmt_plp_mc_tree, hf_alp_lmt_plp_mc_dst_ip, tvb, offset, 4, ENC_BIG_ENDIAN);
 499                     offset += 4;
 500
 501                     proto_tree_add_item(lmt_plp_mc_tree, hf_alp_lmt_plp_mc_src_port, tvb, offset, 2, ENC_BIG_ENDIAN);
 502                     offset += 2;
 503
 504                     proto_tree_add_item(lmt_plp_mc_tree, hf_alp_lmt_plp_mc_dst_port, tvb, offset, 2, ENC_BIG_ENDIAN);
 505                     offset += 2;
 506
 507                     proto_tree_add_item(lmt_plp_mc_tree, hf_alp_lmt_plp_mc_sid_flag, tvb, offset, 1, ENC_BIG_ENDIAN);
 508                     proto_tree_add_item(lmt_plp_mc_tree, hf_alp_lmt_plp_mc_comp_flag, tvb, offset, 1, ENC_BIG_ENDIAN);
 509                     proto_tree_add_item(lmt_plp_mc_tree, hf_alp_lmt_plp_mc_reserved, tvb, offset, 1, ENC_BIG_ENDIAN);
 510                     offset += 1;
 511
 512                     if (lmt_mc_plp_sid_flag) {
 513                         proto_tree_add_item(lmt_plp_mc_tree, hf_alp_lmt_plp_mc_sid, tvb, offset, 1, ENC_BIG_ENDIAN);
 514                         offset += 1;
 515                     }
 516                     if (lmt_mc_plp_comp_flag) {
 517                         proto_tree_add_item(lmt_plp_mc_tree, hf_alp_lmt_plp_mc_context_id, tvb, offset, 1, ENC_BIG_ENDIAN);
 518                         offset += 1;
 519                     }
 520                 }
 521             }
 522         }
 523     }
 524
 525     if (payload_length > 0) {
 526         tvbuff_t *payload_tvb = tvb_new_subset_length(tvb, offset, payload_length);
 527         offset += payload_length;
 528
 529         if ((packet_type == ALP_PACKET_TYPE_IPV4) && (payload_configuration == 0)) {
 530             call_dissector(ip_handle, payload_tvb, pinfo, tree);
 531         } else {
 532             call_data_dissector(payload_tvb, pinfo, tree);
 533         }
 534     }
 535
 536     if (offset < (int)tvb_captured_length(tvb)) {
 537         int junk_length = tvb_captured_length(tvb) - offset;
 538         proto_tree_add_bytes_format(alp_tree, hf_alp_junk, tvb, offset, -1, NULL, "Junk at end (%u byte%s)", junk_length, (junk_length == 1) ? "" : "s");
 539     }
 540
 541     return tvb_captured_length(tvb);
 542 }
 543
 544 void
 545 proto_register_alp(void)
 546 {
 547     static hf_register_info hf[] = {
 548         { &hf_alp_packet_type, {
 549             "Packet Type", "alp.type",
 550             FT_UINT8, BASE_DEC, VALS(alp_packet_type_vals), ALP_PACKET_TYPE_MASK, NULL, HFILL
 551         } },
 552
 553         { &hf_alp_mpegts_numts, {
 554             "Number of TS packets", "alp.numts",
 555             FT_UINT8, BASE_DEC, NULL, 0, NULL, HFILL
 556         } },
 557         { &hf_alp_mpegts_ahf, {
 558             "Additional Header Flag", "alp.ahf",
 559             FT_UINT8, BASE_DEC, NULL, ALP_MPEGTS_AHF_MASK, NULL, HFILL
 560         } },
 561         { &hf_alp_mpegts_hdm, {
 562             "Header Deletion Mode", "alp.hdm",
 563             FT_UINT8, BASE_DEC, NULL, ALP_MPEGTS_HDM_MASK, NULL, HFILL
 564         } },
 565         { &hf_alp_mpegts_dnp, {
 566             "Deleted Null Packets", "alp.dnp",
 567             FT_UINT8, BASE_DEC, NULL, 0, NULL, HFILL
 568         } },
 569
 570         { &hf_alp_payload_configuration, {
 571             "Payload Configuration", "alp.pc",
 572             FT_UINT8, BASE_DEC, NULL, ALP_PAYLOAD_CONFIGURATION_MASK, NULL, HFILL
 573         } },
 574         { &hf_alp_header_mode, {
 575             "Header Mode", "alp.hm",
 576             FT_UINT8, BASE_DEC, NULL, ALP_HEADER_MODE_MASK, NULL, HFILL
 577         } },
 578         { &hf_alp_segmentation_concatenation, {
 579             "Segmentation Concatenation", "alp.sc",
 580             FT_UINT8, BASE_DEC, VALS(alp_segmentation_concatenation_vals), ALP_SEGMENTATION_CONCATENATION_MASK, NULL, HFILL
 581         } },
 582
 583         { &hf_alp_length, {
 584             "Length", "alp.length",
 585             FT_UINT16, BASE_DEC, NULL, ALP_LENGTH_MASK, NULL, HFILL
 586         } },
 587
 588         { &hf_alp_single_length, {
 589             "Length", "alp.length",
 590             FT_UINT24, BASE_DEC, NULL, ALP_SINGLE_LENGTH_MASK, NULL, HFILL
 591         } },
 592         { &hf_alp_single_sif, {
 593             "Sub-stream Identifier Flag", "alp.sif",
 594             FT_UINT8, BASE_DEC, NULL, ALP_SINGLE_SIF_MASK, NULL, HFILL
 595         } },
 596         { &hf_alp_single_hef, {
 597             "Header Extension Flag", "alp.hef",
 598             FT_UINT8, BASE_DEC, NULL, ALP_SINGLE_HEF_MASK, NULL, HFILL
 599         } },
 600
 601         { &hf_alp_segment_sequence_number, {
 602             "Segment Sequence Number", "alp.ssn",
 603             FT_UINT8, BASE_DEC, NULL, ALP_SEGMENT_SEQUENCE_NUMBER_MASK, NULL, HFILL
 604         } },
 605         { &hf_alp_segment_last_indicator, {
 606             "Last Segment Indicator", "alp.lsi",
 607             FT_UINT8, BASE_DEC, NULL, ALP_SEGMENT_LAST_INDICATOR_MASK, NULL, HFILL
 608         } },
 609         { &hf_alp_segment_sif, {
 610             "Sub-stream Identifier Flag", "alp.sif",
 611             FT_UINT8, BASE_DEC, NULL, ALP_SEGMENT_SIF_MASK, NULL, HFILL
 612         } },
 613         { &hf_alp_segment_hef, {
 614             "Header Extension Flag", "alp.hef",
 615             FT_UINT8, BASE_DEC, NULL, ALP_SEGMENT_HEF_MASK, NULL, HFILL
 616         } },
 617
 618         { &hf_alp_concat_length, {
 619             "Length", "alp.length",
 620             FT_UINT24, BASE_DEC, NULL, ALP_CONCAT_LENGTH_MASK, NULL, HFILL
 621         } },
 622         { &hf_alp_concat_count, {
 623             "Concatenation Count", "alp.cc",
 624             FT_UINT8, BASE_DEC, NULL, ALP_CONCAT_COUNT_MASK, NULL, HFILL
 625         } },
 626         { &hf_alp_concat_sif, {
 627             "Sub-stream Identifier Flag", "alp.sif",
 628             FT_UINT8, BASE_DEC, NULL, ALP_CONCAT_SIF_MASK, NULL, HFILL
 629         } },
 630
 631         { &hf_alp_si, {
 632             "Sub-stream Identification", "alp.si",
 633             FT_NONE, BASE_NONE, NULL, 0, NULL, HFILL
 634         } },
 635         { &hf_alp_sid, {
 636             "Sub-stream Identifier", "alp.si_sid",
 637             FT_UINT8, BASE_DEC, NULL, 0, NULL, HFILL
 638         } },
 639
 640         { &hf_alp_header_extension, {
 641             "Header Extension", "alp.he",
 642             FT_NONE, BASE_NONE, NULL, 0, NULL, HFILL
 643         } },
 644         { &hf_alp_header_extension_type, {
 645             "Header Extension Type", "alp.he.type",
 646             FT_UINT8, BASE_HEX, NULL, 0, NULL, HFILL
 647         } },
 648         { &hf_alp_header_extension_length, {
 649             "Header Extension Length", "alp.he.length",
 650             FT_UINT8, BASE_DEC|BASE_UNIT_STRING, UNS(&units_byte_bytes), 0, NULL, HFILL
 651         } },
 652
 653         { &hf_alp_header_extension_sony_l1d_timeinfo, {
 654             "Sony L1D Time Info Extension Raw", "alp.he.sony_l1d_timeinfo",
 655             FT_UINT64, BASE_HEX, NULL, 0, NULL, HFILL
 656         } },
 657         { &hf_alp_header_extension_sony_l1d_timeinfo_flag, {
 658             "Sony L1D Time Info Flag", "alp.he.sony_l1d_timeinfo.flag",
 659             FT_UINT64, BASE_HEX, NULL, ALP_HE_SONY_L1D_TIME_FLAG_MASK, NULL, HFILL
 660         } },
 661         { &hf_alp_header_extension_sony_l1d_timeinfo_sec, {
 662             "Sony L1D Time Info Seconds", "alp.he.sony_l1d_timeinfo.sec",
 663             FT_UINT64, BASE_DEC, NULL, ALP_HE_SONY_L1D_TIME_SEC_MASK, NULL, HFILL
 664         } },
 665         { &hf_alp_header_extension_sony_l1d_timeinfo_ms, {
 666             "Sony L1D Time Info Milliseconds", "alp.he.sony_l1d_timeinfo.ms",
 667             FT_UINT64, BASE_DEC, NULL, ALP_HE_SONY_L1D_TIME_MS_MASK, NULL, HFILL
 668         } },
 669         { &hf_alp_header_extension_sony_l1d_timeinfo_us, {
 670             "Sony L1D Time Info Microseconds", "alp.he.sony_l1d_timeinfo.us",
 671             FT_UINT64, BASE_DEC, NULL, ALP_HE_SONY_L1D_TIME_US_MASK, NULL, HFILL
 672         } },
 673         { &hf_alp_header_extension_sony_l1d_timeinfo_ns, {
 674             "Sony L1D Time Info Nanoseconds", "alp.he.sony_l1d_timeinfo.ns",
 675             FT_UINT64, BASE_DEC, NULL, ALP_HE_SONY_L1D_TIME_NS_MASK, NULL, HFILL
 676         } },
 677         { &hf_alp_header_extension_sony_l1d_timeinfo_time, {
 678             "Sony L1D Time Info TAI Time", "alp.he.sony_l1d_timeinfo.time",
 679             FT_ABSOLUTE_TIME, ABSOLUTE_TIME_LOCAL, NULL, 0, NULL, HFILL
 680         } },
 681         { &hf_alp_header_extension_sony_l1d_timeinfo_time_ns, {
 682             "Sony L1D Time Info TAI Time (ns)", "alp.he.sony_l1d_timeinfo.time_ns",
 683             FT_UINT64, BASE_DEC, NULL, 0, NULL, HFILL
 684         } },
 685
 686         { &hf_alp_header_extension_sony_plp_id, {
 687             "Sony PLP Extension PLP ID", "alp.he.sony_plp.id",
 688             FT_UINT8, BASE_DEC, NULL, ALP_HE_SONY_PLP_NUM_MASK, NULL, HFILL
 689         } },
 690         { &hf_alp_header_extension_sony_plp_unk, {
 691             "Sony PLP Extension Unknown Bits", "alp.he.sony_plp.unknown",
 692             FT_UINT8, BASE_HEX, NULL, ALP_HE_SONY_PLP_UNK_MASK, NULL, HFILL
 693         } },
 694
 695         { &hf_alp_sig_info, {
 696             "Signalling Information Header", "alp.sih",
 697             FT_NONE, BASE_NONE, NULL, 0, NULL, HFILL
 698         } },
 699         { &hf_alp_sig_info_type, {
 700             "Signalling Type", "alp.sih_type",
 701             FT_UINT8, BASE_HEX, VALS(alp_sig_info_type_vals), 0, NULL, HFILL
 702         } },
 703         { &hf_alp_sig_info_type_extension, {
 704             "Signalling Type Extension", "alp.sih_type_ext",
 705             FT_UINT16, BASE_HEX, NULL, 0, NULL, HFILL
 706         } },
 707         { &hf_alp_sig_info_version, {
 708             "Signalling Version", "alp.sih_version",
 709             FT_UINT8, BASE_HEX, NULL, 0, NULL, HFILL
 710         } },
 711         { &hf_alp_sig_info_format, {
 712             "Signalling Format", "alp.sih_format",
 713             FT_UINT8, BASE_DEC, VALS(alp_sig_info_format_vals), ALP_SIG_INFO_FORMAT_MASK, NULL, HFILL
 714         } },
 715         { &hf_alp_sig_info_encoding, {
 716             "Signalling Encoding", "alp.sih_encoding",
 717             FT_UINT8, BASE_DEC, VALS(alp_sig_info_encoding_vals), ALP_SIG_INFO_ENCODING_MASK, NULL, HFILL
 718         } },
 719
 720         { &hf_alp_lmt, {
 721             "Link Mapping Table", "alp.lmt",
 722             FT_NONE, BASE_NONE, NULL, 0, NULL, HFILL
 723         } },
 724         { &hf_alp_lmt_numplp, {
 725             "Number of PLPs", "alp.lmt.numplp",
 726             FT_UINT8, BASE_DEC, NULL, 0, NULL, HFILL
 727         } },
 728         { &hf_alp_lmt_reserved, {
 729             "Reserved", "alp.lmt.reserved",
 730             FT_UINT8, BASE_HEX, NULL, ALP_LMT_RESERVED_MASK, NULL, HFILL
 731         } },
 732
 733         { &hf_alp_lmt_plp, {
 734             "PLP", "alp.plp",
 735             FT_NONE, BASE_NONE, NULL, 0, NULL, HFILL
 736         } },
 737         { &hf_alp_lmt_plp_id, {
 738             "PLP ID", "alp.plp.id",
 739             FT_UINT8, BASE_DEC, NULL, ALP_LMT_PLP_ID_MASK, NULL, HFILL
 740         } },
 741         { &hf_alp_lmt_plp_reserved, {
 742             "Reserved", "alp.plp.reserved",
 743             FT_UINT8, BASE_HEX, NULL, ALP_LMT_PLP_RESERVED_MASK, NULL, HFILL
 744         } },
 745         { &hf_alp_lmt_plp_nummc, {
 746             "Number of Multicast Entries", "alp.plp.nummc",
 747             FT_UINT8, BASE_DEC, NULL, 0, NULL, HFILL
 748         } },
 749         { &hf_alp_lmt_plp_mc, {
 750             "Multicast Entry", "alp.plp.mc",
 751             FT_NONE, BASE_NONE, NULL, 0, NULL, HFILL
 752         } },
 753         { &hf_alp_lmt_plp_mc_src_ip, {
 754             "Source IP", "alp.plp.mc.src_ip",
 755             FT_IPv4, BASE_NONE, NULL, 0, NULL, HFILL
 756         } },
 757         { &hf_alp_lmt_plp_mc_dst_ip, {
 758             "Destination IP", "alp.plp.mc.dst_ip",
 759             FT_IPv4, BASE_NONE, NULL, 0, NULL, HFILL
 760         } },
 761         { &hf_alp_lmt_plp_mc_src_port, {
 762             "Source Port", "alp.plp.mc.src_port",
 763             FT_UINT16, BASE_DEC, NULL, 0, NULL, HFILL
 764         } },
 765         { &hf_alp_lmt_plp_mc_dst_port, {
 766             "Destination IP", "alp.plp.mc.dst_port",
 767             FT_UINT16, BASE_DEC, NULL, 0, NULL, HFILL
 768         } },
 769         { &hf_alp_lmt_plp_mc_sid_flag, {
 770             "SID Flag", "alp.plp.mc.sid_flag",
 771             FT_UINT8, BASE_DEC, NULL, ALP_LMT_PLP_MC_SID_MASK, NULL, HFILL
 772         } },
 773         { &hf_alp_lmt_plp_mc_comp_flag, {
 774             "Compressed Flag", "alp.plp.mc.comp_flag",
 775             FT_UINT8, BASE_DEC, NULL, ALP_LMT_PLP_MC_COMP_MASK, NULL, HFILL
 776         } },
 777         { &hf_alp_lmt_plp_mc_reserved, {
 778             "Reserved", "alp.plp.mc.reserved",
 779             FT_UINT8, BASE_HEX, NULL, ALP_LMT_PLP_MC_RESERVED_MASK, NULL, HFILL
 780         } },
 781         { &hf_alp_lmt_plp_mc_sid, {
 782             "Reserved", "alp.plp.mc.sid",
 783             FT_UINT8, BASE_DEC, NULL, 0, NULL, HFILL
 784         } },
 785         { &hf_alp_lmt_plp_mc_context_id, {
 786             "Reserved", "alp.plp.mc.context_id",
 787             FT_UINT8, BASE_HEX, NULL, 0, NULL, HFILL
 788         } },
 789
 790         { &hf_alp_junk, {
 791             "Junk", "alp.junk",
 792             FT_BYTES, BASE_NONE, NULL, 0, NULL, HFILL
 793         } },
 794     };
 795
 796     static int *ett[] = {
 797         &ett_alp,
 798         &ett_alp_si,
 799         &ett_alp_he,
 800         &ett_alp_sig_info,
 801         &ett_alp_lmt,
 802         &ett_alp_lmt_plp,
 803         &ett_alp_lmt_plp_mc,
 804     };
 805
 806     proto_alp = proto_register_protocol("ATSC Link-Layer Protocol", "ALP", "alp");
 807     proto_register_field_array(proto_alp, hf, array_length(hf));
 808     proto_register_subtree_array(ett, array_length(ett));
 809 }
 810
 811 void
 812 proto_reg_handoff_alp(void)
 813 {
 814     alp_handle = create_dissector_handle(dissect_alp, proto_alp);
 815     dissector_add_uint("wtap_encap", WTAP_ENCAP_ATSC_ALP, alp_handle);
 816
 817     ip_handle = find_dissector("ip");
 818     ts_handle = find_dissector("mp2t");
 819 }
 820
 821 /*
 822  * Editor modelines  -  https://www.wireshark.org/tools/modelines.html
 823  *
 824  * Local variables:
 825  * c-basic-offset: 4
 826  * tab-width: 8
 827  * indent-tabs-mode: nil
 828  * End:
 829  *
 830  * vi: set shiftwidth=4 tabstop=8 expandtab:
 831  * :indentSize=4:tabSize=8:noTabs=true:
 832  */