plugins/ctf/common/metadata/decoder.c

   1 /*
   2  * Copyright 2016-2017 - Philippe Proulx <pproulx@efficios.com>
   3  *
   4  * Permission is hereby granted, free of charge, to any person obtaining a copy
   5  * of this software and associated documentation files (the "Software"), to deal
   6  * in the Software without restriction, including without limitation the rights
   7  * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
   8  * copies of the Software, and to permit persons to whom the Software is
   9  * furnished to do so, subject to the following conditions:
  10  *
  11  * The above copyright notice and this permission notice shall be included in
  12  * all copies or substantial portions of the Software.
  13  */
  14
  15 #define BT_LOG_TAG "PLUGIN-CTF-METADATA-DECODER"
  16 #include "logging.h"
  17
  18 #include <stdio.h>
  19 #include <stdbool.h>
  20 #include <stdint.h>
  21 #include <stdlib.h>
  22 #include <inttypes.h>
  23 #include <babeltrace/assert-internal.h>
  24 #include <babeltrace/compat/uuid-internal.h>
  25 #include <babeltrace/compat/memstream-internal.h>
  26 #include <babeltrace/babeltrace.h>
  27 #include <glib.h>
  28 #include <string.h>
  29
  30 #include "ast.h"
  31 #include "decoder.h"
  32 #include "scanner.h"
  33
  34 #define TSDL_MAGIC      0x75d11d57
  35
  36 extern
  37 int yydebug;
  38
  39 struct ctf_metadata_decoder {
  40         struct ctf_visitor_generate_ir *visitor;
  41         uint8_t uuid[16];
  42         bool is_uuid_set;
  43         int bo;
  44         struct ctf_metadata_decoder_config config;
  45 };
  46
  47 struct packet_header {
  48         uint32_t magic;
  49         uint8_t  uuid[16];
  50         uint32_t checksum;
  51         uint32_t content_size;
  52         uint32_t packet_size;
  53         uint8_t  compression_scheme;
  54         uint8_t  encryption_scheme;
  55         uint8_t  checksum_scheme;
  56         uint8_t  major;
  57         uint8_t  minor;
  58 } __attribute__((__packed__));
  59
  60 BT_HIDDEN
  61 bool ctf_metadata_decoder_is_packetized(FILE *fp, int *byte_order)
  62 {
  63         uint32_t magic;
  64         size_t len;
  65         int ret = 0;
  66
  67         len = fread(&magic, sizeof(magic), 1, fp);
  68         if (len != 1) {
  69                 BT_LOGD_STR("Cannot reade first metadata packet header: assuming the stream is not packetized.");
  70                 goto end;
  71         }
  72
  73         if (byte_order) {
  74                 if (magic == TSDL_MAGIC) {
  75                         ret = 1;
  76                         *byte_order = BYTE_ORDER;
  77                 } else if (magic == GUINT32_SWAP_LE_BE(TSDL_MAGIC)) {
  78                         ret = 1;
  79                         *byte_order = BYTE_ORDER == BIG_ENDIAN ?
  80                                 LITTLE_ENDIAN : BIG_ENDIAN;
  81                 }
  82         }
  83
  84 end:
  85         rewind(fp);
  86
  87         return ret;
  88 }
  89
  90 static
  91 bool is_version_valid(unsigned int major, unsigned int minor)
  92 {
  93         return major == 1 && minor == 8;
  94 }
  95
  96 static
  97 int decode_packet(struct ctf_metadata_decoder *mdec, FILE *in_fp, FILE *out_fp,
  98                 int byte_order)
  99 {
 100         struct packet_header header;
 101         size_t readlen, writelen, toread;
 102         uint8_t buf[512 + 1];   /* + 1 for debug-mode \0 */
 103         int ret = 0;
 104         const long offset = ftell(in_fp);
 105
 106         if (offset < 0) {
 107                 BT_LOGE_ERRNO("Failed to get current metadata file position",
 108                         ".");
 109                 goto error;
 110         }
 111         BT_LOGV("Decoding metadata packet: mdec-addr=%p, offset=%ld",
 112                 mdec, offset);
 113         readlen = fread(&header, sizeof(header), 1, in_fp);
 114         if (feof(in_fp) != 0) {
 115                 BT_LOGV("Reached end of file: offset=%ld", ftell(in_fp));
 116                 goto end;
 117         }
 118         if (readlen < 1) {
 119                 BT_LOGV("Cannot decode metadata packet: offset=%ld", offset);
 120                 goto error;
 121         }
 122
 123         if (byte_order != BYTE_ORDER) {
 124                 header.magic = GUINT32_SWAP_LE_BE(header.magic);
 125                 header.checksum = GUINT32_SWAP_LE_BE(header.checksum);
 126                 header.content_size = GUINT32_SWAP_LE_BE(header.content_size);
 127                 header.packet_size = GUINT32_SWAP_LE_BE(header.packet_size);
 128         }
 129
 130         if (header.compression_scheme) {
 131                 BT_LOGE("Metadata packet compression is not supported as of this version: "
 132                         "compression-scheme=%u, offset=%ld",
 133                         (unsigned int) header.compression_scheme, offset);
 134                 goto error;
 135         }
 136
 137         if (header.encryption_scheme) {
 138                 BT_LOGE("Metadata packet encryption is not supported as of this version: "
 139                         "encryption-scheme=%u, offset=%ld",
 140                         (unsigned int) header.encryption_scheme, offset);
 141                 goto error;
 142         }
 143
 144         if (header.checksum || header.checksum_scheme) {
 145                 BT_LOGE("Metadata packet checksum verification is not supported as of this version: "
 146                         "checksum-scheme=%u, checksum=%x, offset=%ld",
 147                         (unsigned int) header.checksum_scheme, header.checksum,
 148                         offset);
 149                 goto error;
 150         }
 151
 152         if (!is_version_valid(header.major, header.minor)) {
 153                 BT_LOGE("Invalid metadata packet version: "
 154                         "version=%u.%u, offset=%ld",
 155                         header.major, header.minor, offset);
 156                 goto error;
 157         }
 158
 159         /* Set expected trace UUID if not set; otherwise validate it */
 160         if (mdec) {
 161                 if (!mdec->is_uuid_set) {
 162                         memcpy(mdec->uuid, header.uuid, sizeof(header.uuid));
 163                         mdec->is_uuid_set = true;
 164                 } else if (bt_uuid_compare(header.uuid, mdec->uuid)) {
 165                         BT_LOGE("Metadata UUID mismatch between packets of the same stream: "
 166                                 "packet-uuid=\"%02x%02x%02x%02x-%02x%02x-%02x%02x-%02x%02x-%02x%02x%02x%02x%02x%02x\", "
 167                                 "expected-uuid=\"%02x%02x%02x%02x-%02x%02x-%02x%02x-%02x%02x-%02x%02x%02x%02x%02x%02x\", "
 168                                 "offset=%ld",
 169                                 (unsigned int) header.uuid[0],
 170                                 (unsigned int) header.uuid[1],
 171                                 (unsigned int) header.uuid[2],
 172                                 (unsigned int) header.uuid[3],
 173                                 (unsigned int) header.uuid[4],
 174                                 (unsigned int) header.uuid[5],
 175                                 (unsigned int) header.uuid[6],
 176                                 (unsigned int) header.uuid[7],
 177                                 (unsigned int) header.uuid[8],
 178                                 (unsigned int) header.uuid[9],
 179                                 (unsigned int) header.uuid[10],
 180                                 (unsigned int) header.uuid[11],
 181                                 (unsigned int) header.uuid[12],
 182                                 (unsigned int) header.uuid[13],
 183                                 (unsigned int) header.uuid[14],
 184                                 (unsigned int) header.uuid[15],
 185                                 (unsigned int) mdec->uuid[0],
 186                                 (unsigned int) mdec->uuid[1],
 187                                 (unsigned int) mdec->uuid[2],
 188                                 (unsigned int) mdec->uuid[3],
 189                                 (unsigned int) mdec->uuid[4],
 190                                 (unsigned int) mdec->uuid[5],
 191                                 (unsigned int) mdec->uuid[6],
 192                                 (unsigned int) mdec->uuid[7],
 193                                 (unsigned int) mdec->uuid[8],
 194                                 (unsigned int) mdec->uuid[9],
 195                                 (unsigned int) mdec->uuid[10],
 196                                 (unsigned int) mdec->uuid[11],
 197                                 (unsigned int) mdec->uuid[12],
 198                                 (unsigned int) mdec->uuid[13],
 199                                 (unsigned int) mdec->uuid[14],
 200                                 (unsigned int) mdec->uuid[15],
 201                                 offset);
 202                         goto error;
 203                 }
 204         }
 205
 206         if ((header.content_size / CHAR_BIT) < sizeof(header)) {
 207                 BT_LOGE("Bad metadata packet content size: content-size=%u, "
 208                         "offset=%ld", header.content_size, offset);
 209                 goto error;
 210         }
 211
 212         toread = header.content_size / CHAR_BIT - sizeof(header);
 213
 214         for (;;) {
 215                 size_t loop_read;
 216
 217                 loop_read = MIN(sizeof(buf) - 1, toread);
 218                 readlen = fread(buf, sizeof(uint8_t), loop_read, in_fp);
 219                 if (ferror(in_fp)) {
 220                         BT_LOGE("Cannot read metadata packet buffer: "
 221                                 "offset=%ld, read-size=%zu",
 222                                 ftell(in_fp), loop_read);
 223                         goto error;
 224                 }
 225                 if (readlen > loop_read) {
 226                         BT_LOGE("fread returned more byte than expected: "
 227                                 "read-size-asked=%zu, read-size-returned=%zu",
 228                                 loop_read, readlen);
 229                         goto error;
 230                 }
 231
 232                 writelen = fwrite(buf, sizeof(uint8_t), readlen, out_fp);
 233                 if (writelen < readlen || ferror(out_fp)) {
 234                         BT_LOGE("Cannot write decoded metadata text to buffer: "
 235                                 "read-offset=%ld, write-size=%zu",
 236                                 ftell(in_fp), readlen);
 237                         goto error;
 238                 }
 239
 240                 toread -= readlen;
 241                 if (toread == 0) {
 242                         int fseek_ret;
 243
 244                         /* Read leftover padding */
 245                         toread = (header.packet_size - header.content_size) /
 246                                 CHAR_BIT;
 247                         fseek_ret = fseek(in_fp, toread, SEEK_CUR);
 248                         if (fseek_ret < 0) {
 249                                 BT_LOGW_STR("Missing padding at the end of the metadata stream.");
 250                         }
 251                         break;
 252                 }
 253         }
 254
 255         goto end;
 256
 257 error:
 258         ret = -1;
 259
 260 end:
 261         return ret;
 262 }
 263
 264 static
 265 int ctf_metadata_decoder_packetized_file_stream_to_buf_with_mdec(
 266                 struct ctf_metadata_decoder *mdec, FILE *fp,
 267                 char **buf, int byte_order)
 268 {
 269         FILE *out_fp;
 270         size_t size;
 271         int ret = 0;
 272         int tret;
 273         size_t packet_index = 0;
 274
 275         out_fp = bt_open_memstream(buf, &size);
 276         if (out_fp == NULL) {
 277                 BT_LOGE("Cannot open memory stream: %s: mdec-addr=%p",
 278                         strerror(errno), mdec);
 279                 goto error;
 280         }
 281
 282         for (;;) {
 283                 if (feof(fp) != 0) {
 284                         break;
 285                 }
 286
 287                 tret = decode_packet(mdec, fp, out_fp, byte_order);
 288                 if (tret) {
 289                         BT_LOGE("Cannot decode packet: index=%zu, mdec-addr=%p",
 290                                 packet_index, mdec);
 291                         goto error;
 292                 }
 293
 294                 packet_index++;
 295         }
 296
 297         /* Make sure the whole string ends with a null character */
 298         tret = fputc('\0', out_fp);
 299         if (tret == EOF) {
 300                 BT_LOGE("Cannot append '\\0' to the decoded metadata buffer: "
 301                         "mdec-addr=%p", mdec);
 302                 goto error;
 303         }
 304
 305         /* Close stream, which also flushes the buffer */
 306         ret = bt_close_memstream(buf, &size, out_fp);
 307         /*
 308          * See fclose(3). Further access to out_fp after both success
 309          * and error, even through another bt_close_memstream(), results
 310          * in undefined behavior. Nullify out_fp to ensure we don't
 311          * fclose it twice on error.
 312          */
 313         out_fp = NULL;
 314         if (ret < 0) {
 315                 BT_LOGE("Cannot close memory stream: %s: mdec-addr=%p",
 316                         strerror(errno), mdec);
 317                 goto error;
 318         }
 319
 320         goto end;
 321
 322 error:
 323         ret = -1;
 324
 325         if (out_fp) {
 326                 if (bt_close_memstream(buf, &size, out_fp)) {
 327                         BT_LOGE("Cannot close memory stream: %s: mdec-addr=%p",
 328                                 strerror(errno), mdec);
 329                 }
 330         }
 331
 332         if (*buf) {
 333                 free(*buf);
 334                 *buf = NULL;
 335         }
 336
 337 end:
 338         return ret;
 339 }
 340
 341 BT_HIDDEN
 342 int ctf_metadata_decoder_packetized_file_stream_to_buf(
 343                 FILE *fp, char **buf, int byte_order)
 344 {
 345         return ctf_metadata_decoder_packetized_file_stream_to_buf_with_mdec(
 346                 NULL, fp, buf, byte_order);
 347 }
 348
 349 BT_HIDDEN
 350 struct ctf_metadata_decoder *ctf_metadata_decoder_create(
 351                 const struct ctf_metadata_decoder_config *config,
 352                 const char *name)
 353 {
 354         struct ctf_metadata_decoder *mdec =
 355                 g_new0(struct ctf_metadata_decoder, 1);
 356         struct ctf_metadata_decoder_config default_config = {
 357                 .clock_class_offset_s = 0,
 358                 .clock_class_offset_ns = 0,
 359         };
 360
 361         if (!config) {
 362                 config = &default_config;
 363         }
 364
 365         BT_LOGD("Creating CTF metadata decoder: "
 366                 "clock-class-offset-s=%" PRId64 ", "
 367                 "clock-class-offset-ns=%" PRId64 ", name=\"%s\"",
 368                 config->clock_class_offset_s, config->clock_class_offset_ns,
 369                 name);
 370
 371         if (!mdec) {
 372                 BT_LOGE_STR("Failed to allocate one CTF metadata decoder.");
 373                 goto end;
 374         }
 375
 376         mdec->config = *config;
 377         mdec->visitor = ctf_visitor_generate_ir_create(config, name);
 378         if (!mdec->visitor) {
 379                 BT_LOGE("Failed to create a CTF IR metadata AST visitor: "
 380                         "mdec-addr=%p", mdec);
 381                 ctf_metadata_decoder_destroy(mdec);
 382                 mdec = NULL;
 383                 goto end;
 384         }
 385
 386         BT_LOGD("Creating CTF metadata decoder: "
 387                 "clock-class-offset-s=%" PRId64 ", "
 388                 "clock-class-offset-ns=%" PRId64 ", "
 389                 "name=\"%s\", addr=%p",
 390                 config->clock_class_offset_s, config->clock_class_offset_ns,
 391                 name, mdec);
 392
 393 end:
 394         return mdec;
 395 }
 396
 397 BT_HIDDEN
 398 void ctf_metadata_decoder_destroy(struct ctf_metadata_decoder *mdec)
 399 {
 400         if (!mdec) {
 401                 return;
 402         }
 403
 404         BT_LOGD("Destroying CTF metadata decoder: addr=%p", mdec);
 405         ctf_visitor_generate_ir_destroy(mdec->visitor);
 406         g_free(mdec);
 407 }
 408
 409 BT_HIDDEN
 410 enum ctf_metadata_decoder_status ctf_metadata_decoder_decode(
 411                 struct ctf_metadata_decoder *mdec, FILE *fp)
 412 {
 413         enum ctf_metadata_decoder_status status =
 414                 CTF_METADATA_DECODER_STATUS_OK;
 415         int ret;
 416         struct ctf_scanner *scanner = NULL;
 417         char *buf = NULL;
 418         bool close_fp = false;
 419
 420         BT_ASSERT(mdec);
 421
 422         if (ctf_metadata_decoder_is_packetized(fp, &mdec->bo)) {
 423                 BT_LOGD("Metadata stream is packetized: mdec-addr=%p", mdec);
 424                 ret = ctf_metadata_decoder_packetized_file_stream_to_buf_with_mdec(
 425                         mdec, fp, &buf, mdec->bo);
 426                 if (ret) {
 427                         BT_LOGE("Cannot decode packetized metadata packets to metadata text: "
 428                                 "mdec-addr=%p, ret=%d", mdec, ret);
 429                         status = CTF_METADATA_DECODER_STATUS_ERROR;
 430                         goto end;
 431                 }
 432
 433                 if (strlen(buf) == 0) {
 434                         /* An empty metadata packet is OK. */
 435                         goto end;
 436                 }
 437
 438                 /* Convert the real file pointer to a memory file pointer */
 439                 fp = bt_fmemopen(buf, strlen(buf), "rb");
 440                 close_fp = true;
 441                 if (!fp) {
 442                         BT_LOGE("Cannot memory-open metadata buffer: %s: "
 443                                 "mdec-addr=%p", strerror(errno), mdec);
 444                         status = CTF_METADATA_DECODER_STATUS_ERROR;
 445                         goto end;
 446                 }
 447         } else {
 448                 unsigned int major, minor;
 449                 ssize_t nr_items;
 450                 const long init_pos = ftell(fp);
 451
 452                 BT_LOGD("Metadata stream is plain text: mdec-addr=%p", mdec);
 453
 454                 if (init_pos < 0) {
 455                         BT_LOGE_ERRNO("Failed to get current file position", ".");
 456                         status = CTF_METADATA_DECODER_STATUS_ERROR;
 457                         goto end;
 458                 }
 459
 460                 /* Check text-only metadata header and version */
 461                 nr_items = fscanf(fp, "/* CTF %10u.%10u", &major, &minor);
 462                 if (nr_items < 2) {
 463                         BT_LOGW("Missing \"/* CTF major.minor\" signature in plain text metadata file stream: "
 464                                 "mdec-addr=%p", mdec);
 465                 }
 466
 467                 BT_LOGD("Found metadata stream version in signature: version=%u.%u", major, minor);
 468
 469                 if (!is_version_valid(major, minor)) {
 470                         BT_LOGE("Invalid metadata version found in plain text signature: "
 471                                 "version=%u.%u, mdec-addr=%p", major, minor,
 472                                 mdec);
 473                         status = CTF_METADATA_DECODER_STATUS_INVAL_VERSION;
 474                         goto end;
 475                 }
 476
 477                 if (fseek(fp, init_pos, SEEK_SET)) {
 478                         BT_LOGE("Cannot seek metadata file stream to initial position: %s: "
 479                                 "mdec-addr=%p", strerror(errno), mdec);
 480                         status = CTF_METADATA_DECODER_STATUS_ERROR;
 481                         goto end;
 482                 }
 483         }
 484
 485         if (BT_LOG_ON_VERBOSE) {
 486                 yydebug = 1;
 487         }
 488
 489         /* Allocate a scanner and append the metadata text content */
 490         scanner = ctf_scanner_alloc();
 491         if (!scanner) {
 492                 BT_LOGE("Cannot allocate a metadata lexical scanner: "
 493                         "mdec-addr=%p", mdec);
 494                 status = CTF_METADATA_DECODER_STATUS_ERROR;
 495                 goto end;
 496         }
 497
 498         BT_ASSERT(fp);
 499         ret = ctf_scanner_append_ast(scanner, fp);
 500         if (ret) {
 501                 BT_LOGE("Cannot create the metadata AST out of the metadata text: "
 502                         "mdec-addr=%p", mdec);
 503                 status = CTF_METADATA_DECODER_STATUS_INCOMPLETE;
 504                 goto end;
 505         }
 506
 507         ret = ctf_visitor_semantic_check(0, &scanner->ast->root);
 508         if (ret) {
 509                 BT_LOGE("Validation of the metadata semantics failed: "
 510                         "mdec-addr=%p", mdec);
 511                 status = CTF_METADATA_DECODER_STATUS_ERROR;
 512                 goto end;
 513         }
 514
 515         ret = ctf_visitor_generate_ir_visit_node(mdec->visitor,
 516                 &scanner->ast->root);
 517         switch (ret) {
 518         case 0:
 519                 /* Success */
 520                 break;
 521         case -EINCOMPLETE:
 522                 BT_LOGD("While visiting metadata AST: incomplete data: "
 523                         "mdec-addr=%p", mdec);
 524                 status = CTF_METADATA_DECODER_STATUS_INCOMPLETE;
 525                 goto end;
 526         default:
 527                 BT_LOGE("Failed to visit AST node to create CTF IR objects: "
 528                         "mdec-addr=%p, ret=%d", mdec, ret);
 529                 status = CTF_METADATA_DECODER_STATUS_IR_VISITOR_ERROR;
 530                 goto end;
 531         }
 532
 533 end:
 534         if (scanner) {
 535                 ctf_scanner_free(scanner);
 536         }
 537
 538         yydebug = 0;
 539
 540         if (fp && close_fp) {
 541                 if (fclose(fp)) {
 542                         BT_LOGE("Cannot close metadata file stream: "
 543                                 "mdec-addr=%p", mdec);
 544                 }
 545         }
 546
 547         if (buf) {
 548                 free(buf);
 549         }
 550
 551         return status;
 552 }
 553
 554 BT_HIDDEN
 555 struct bt_trace *ctf_metadata_decoder_get_trace(
 556                 struct ctf_metadata_decoder *mdec)
 557 {
 558         return ctf_visitor_generate_ir_get_trace(mdec->visitor);
 559 }