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 <assert.h>
  24 #include <babeltrace/compat/uuid-internal.h>
  25 #include <babeltrace/compat/memstream-internal.h>
  26 #include <babeltrace/ctf-ir/trace.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         BT_LOGV("Decoding metadata packet: mdec-addr=%p, offset=%ld",
 107                 mdec, offset);
 108         readlen = fread(&header, sizeof(header), 1, in_fp);
 109         if (feof(in_fp) != 0) {
 110                 BT_LOGV("Reached end of file: offset=%ld", ftell(in_fp));
 111                 goto end;
 112         }
 113         if (readlen < 1) {
 114                 BT_LOGV("Cannot decode metadata packet: offset=%ld", offset);
 115                 goto error;
 116         }
 117
 118         if (byte_order != BYTE_ORDER) {
 119                 header.magic = GUINT32_SWAP_LE_BE(header.magic);
 120                 header.checksum = GUINT32_SWAP_LE_BE(header.checksum);
 121                 header.content_size = GUINT32_SWAP_LE_BE(header.content_size);
 122                 header.packet_size = GUINT32_SWAP_LE_BE(header.packet_size);
 123         }
 124
 125         if (header.compression_scheme) {
 126                 BT_LOGE("Metadata packet compression is not supported as of this version: "
 127                         "compression-scheme=%u, offset=%ld",
 128                         (unsigned int) header.compression_scheme, offset);
 129                 goto error;
 130         }
 131
 132         if (header.encryption_scheme) {
 133                 BT_LOGE("Metadata packet encryption is not supported as of this version: "
 134                         "encryption-scheme=%u, offset=%ld",
 135                         (unsigned int) header.encryption_scheme, offset);
 136                 goto error;
 137         }
 138
 139         if (header.checksum || header.checksum_scheme) {
 140                 BT_LOGE("Metadata packet checksum verification is not supported as of this version: "
 141                         "checksum-scheme=%u, checksum=%x, offset=%ld",
 142                         (unsigned int) header.checksum_scheme, header.checksum,
 143                         offset);
 144                 goto error;
 145         }
 146
 147         if (!is_version_valid(header.major, header.minor)) {
 148                 BT_LOGE("Invalid metadata packet version: "
 149                         "version=%u.%u, offset=%ld",
 150                         header.major, header.minor, offset);
 151                 goto error;
 152         }
 153
 154         /* Set expected trace UUID if not set; otherwise validate it */
 155         if (mdec) {
 156                 if (!mdec->is_uuid_set) {
 157                         memcpy(mdec->uuid, header.uuid, sizeof(header.uuid));
 158                         mdec->is_uuid_set = true;
 159                 } else if (bt_uuid_compare(header.uuid, mdec->uuid)) {
 160                         BT_LOGE("Metadata UUID mismatch between packets of the same stream: "
 161                                 "packet-uuid=\"%02x%02x%02x%02x-%02x%02x-%02x%02x-%02x%02x-%02x%02x%02x%02x%02x%02x\", "
 162                                 "expected-uuid=\"%02x%02x%02x%02x-%02x%02x-%02x%02x-%02x%02x-%02x%02x%02x%02x%02x%02x\", "
 163                                 "offset=%ld",
 164                                 (unsigned int) header.uuid[0],
 165                                 (unsigned int) header.uuid[1],
 166                                 (unsigned int) header.uuid[2],
 167                                 (unsigned int) header.uuid[3],
 168                                 (unsigned int) header.uuid[4],
 169                                 (unsigned int) header.uuid[5],
 170                                 (unsigned int) header.uuid[6],
 171                                 (unsigned int) header.uuid[7],
 172                                 (unsigned int) header.uuid[8],
 173                                 (unsigned int) header.uuid[9],
 174                                 (unsigned int) header.uuid[10],
 175                                 (unsigned int) header.uuid[11],
 176                                 (unsigned int) header.uuid[12],
 177                                 (unsigned int) header.uuid[13],
 178                                 (unsigned int) header.uuid[14],
 179                                 (unsigned int) header.uuid[15],
 180                                 (unsigned int) mdec->uuid[0],
 181                                 (unsigned int) mdec->uuid[1],
 182                                 (unsigned int) mdec->uuid[2],
 183                                 (unsigned int) mdec->uuid[3],
 184                                 (unsigned int) mdec->uuid[4],
 185                                 (unsigned int) mdec->uuid[5],
 186                                 (unsigned int) mdec->uuid[6],
 187                                 (unsigned int) mdec->uuid[7],
 188                                 (unsigned int) mdec->uuid[8],
 189                                 (unsigned int) mdec->uuid[9],
 190                                 (unsigned int) mdec->uuid[10],
 191                                 (unsigned int) mdec->uuid[11],
 192                                 (unsigned int) mdec->uuid[12],
 193                                 (unsigned int) mdec->uuid[13],
 194                                 (unsigned int) mdec->uuid[14],
 195                                 (unsigned int) mdec->uuid[15],
 196                                 offset);
 197                         goto error;
 198                 }
 199         }
 200
 201         if ((header.content_size / CHAR_BIT) < sizeof(header)) {
 202                 BT_LOGE("Bad metadata packet content size: content-size=%u, "
 203                         "offset=%ld", header.content_size, offset);
 204                 goto error;
 205         }
 206
 207         toread = header.content_size / CHAR_BIT - sizeof(header);
 208
 209         for (;;) {
 210                 readlen = fread(buf, sizeof(uint8_t),
 211                         MIN(sizeof(buf) - 1, toread), in_fp);
 212                 if (ferror(in_fp)) {
 213                         BT_LOGE("Cannot read metadata packet buffer: "
 214                                 "offset=%ld, read-size=%u",
 215                                 ftell(in_fp), (unsigned int) readlen);
 216                         goto error;
 217                 }
 218
 219                 writelen = fwrite(buf, sizeof(uint8_t), readlen, out_fp);
 220                 if (writelen < readlen || ferror(out_fp)) {
 221                         BT_LOGE("Cannot write decoded metadata text to buffer: "
 222                                 "read-offset=%ld, write-size=%u",
 223                                 ftell(in_fp), (unsigned int) readlen);
 224                         goto error;
 225                 }
 226
 227                 toread -= readlen;
 228                 if (toread == 0) {
 229                         int fseek_ret;
 230
 231                         /* Read leftover padding */
 232                         toread = (header.packet_size - header.content_size) /
 233                                 CHAR_BIT;
 234                         fseek_ret = fseek(in_fp, toread, SEEK_CUR);
 235                         if (fseek_ret < 0) {
 236                                 BT_LOGW_STR("Missing padding at the end of the metadata stream.");
 237                         }
 238                         break;
 239                 }
 240         }
 241
 242         goto end;
 243
 244 error:
 245         ret = -1;
 246
 247 end:
 248         return ret;
 249 }
 250
 251 static
 252 int ctf_metadata_decoder_packetized_file_stream_to_buf_with_mdec(
 253                 struct ctf_metadata_decoder *mdec, FILE *fp,
 254                 char **buf, int byte_order)
 255 {
 256         FILE *out_fp;
 257         size_t size;
 258         int ret = 0;
 259         int tret;
 260         size_t packet_index = 0;
 261
 262         out_fp = bt_open_memstream(buf, &size);
 263         if (out_fp == NULL) {
 264                 BT_LOGE("Cannot open memory stream: %s: mdec-addr=%p",
 265                         strerror(errno), mdec);
 266                 goto error;
 267         }
 268
 269         for (;;) {
 270                 if (feof(fp) != 0) {
 271                         break;
 272                 }
 273
 274                 tret = decode_packet(mdec, fp, out_fp, byte_order);
 275                 if (tret) {
 276                         BT_LOGE("Cannot decode packet: index=%zu, mdec-addr=%p",
 277                                 packet_index, mdec);
 278                         goto error;
 279                 }
 280
 281                 packet_index++;
 282         }
 283
 284         /* Make sure the whole string ends with a null character */
 285         tret = fputc('\0', out_fp);
 286         if (tret == EOF) {
 287                 BT_LOGE("Cannot append '\\0' to the decoded metadata buffer: "
 288                         "mdec-addr=%p", mdec);
 289                 goto error;
 290         }
 291
 292         /* Close stream, which also flushes the buffer */
 293         ret = bt_close_memstream(buf, &size, out_fp);
 294         /*
 295          * See fclose(3). Further access to out_fp after both success
 296          * and error, even through another bt_close_memstream(), results
 297          * in undefined behavior. Nullify out_fp to ensure we don't
 298          * fclose it twice on error.
 299          */
 300         out_fp = NULL;
 301         if (ret < 0) {
 302                 BT_LOGE("Cannot close memory stream: %s: mdec-addr=%p",
 303                         strerror(errno), mdec);
 304                 goto error;
 305         }
 306
 307         goto end;
 308
 309 error:
 310         ret = -1;
 311
 312         if (out_fp) {
 313                 if (bt_close_memstream(buf, &size, out_fp)) {
 314                         BT_LOGE("Cannot close memory stream: %s: mdec-addr=%p",
 315                                 strerror(errno), mdec);
 316                 }
 317         }
 318
 319         if (*buf) {
 320                 free(*buf);
 321                 *buf = NULL;
 322         }
 323
 324 end:
 325         return ret;
 326 }
 327
 328 BT_HIDDEN
 329 int ctf_metadata_decoder_packetized_file_stream_to_buf(
 330                 FILE *fp, char **buf, int byte_order)
 331 {
 332         return ctf_metadata_decoder_packetized_file_stream_to_buf_with_mdec(
 333                 NULL, fp, buf, byte_order);
 334 }
 335
 336 BT_HIDDEN
 337 struct ctf_metadata_decoder *ctf_metadata_decoder_create(
 338                 const struct ctf_metadata_decoder_config *config,
 339                 const char *name)
 340 {
 341         struct ctf_metadata_decoder *mdec =
 342                 g_new0(struct ctf_metadata_decoder, 1);
 343         struct ctf_metadata_decoder_config default_config = {
 344                 .clock_class_offset_s = 0,
 345                 .clock_class_offset_ns = 0,
 346         };
 347
 348         if (!config) {
 349                 config = &default_config;
 350         }
 351
 352         BT_LOGD("Creating CTF metadata decoder: "
 353                 "clock-class-offset-s=%" PRId64 ", "
 354                 "clock-class-offset-ns=%" PRId64 ", name=\"%s\"",
 355                 config->clock_class_offset_s, config->clock_class_offset_ns,
 356                 name);
 357
 358         if (!mdec) {
 359                 BT_LOGE_STR("Failed to allocate one CTF metadata decoder.");
 360                 goto end;
 361         }
 362
 363         mdec->config = *config;
 364         mdec->visitor = ctf_visitor_generate_ir_create(config, name);
 365         if (!mdec->visitor) {
 366                 BT_LOGE("Failed to create a CTF IR metadata AST visitor: "
 367                         "mdec-addr=%p", mdec);
 368                 ctf_metadata_decoder_destroy(mdec);
 369                 mdec = NULL;
 370                 goto end;
 371         }
 372
 373         BT_LOGD("Creating CTF metadata decoder: "
 374                 "clock-class-offset-s=%" PRId64 ", "
 375                 "clock-class-offset-ns=%" PRId64 ", "
 376                 "name=\"%s\", addr=%p",
 377                 config->clock_class_offset_s, config->clock_class_offset_ns,
 378                 name, mdec);
 379
 380 end:
 381         return mdec;
 382 }
 383
 384 BT_HIDDEN
 385 void ctf_metadata_decoder_destroy(struct ctf_metadata_decoder *mdec)
 386 {
 387         if (!mdec) {
 388                 return;
 389         }
 390
 391         BT_LOGD("Destroying CTF metadata decoder: addr=%p", mdec);
 392         ctf_visitor_generate_ir_destroy(mdec->visitor);
 393         g_free(mdec);
 394 }
 395
 396 BT_HIDDEN
 397 enum ctf_metadata_decoder_status ctf_metadata_decoder_decode(
 398                 struct ctf_metadata_decoder *mdec, FILE *fp)
 399 {
 400         enum ctf_metadata_decoder_status status =
 401                 CTF_METADATA_DECODER_STATUS_OK;
 402         int ret;
 403         struct ctf_scanner *scanner = NULL;
 404         char *buf = NULL;
 405         bool close_fp = false;
 406
 407         assert(mdec);
 408
 409         if (ctf_metadata_decoder_is_packetized(fp, &mdec->bo)) {
 410                 BT_LOGD("Metadata stream is packetized: mdec-addr=%p", mdec);
 411                 ret = ctf_metadata_decoder_packetized_file_stream_to_buf_with_mdec(
 412                         mdec, fp, &buf, mdec->bo);
 413                 if (ret) {
 414                         BT_LOGE("Cannot decode packetized metadata packets to metadata text: "
 415                                 "mdec-addr=%p, ret=%d", mdec, ret);
 416                         status = CTF_METADATA_DECODER_STATUS_ERROR;
 417                         goto end;
 418                 }
 419
 420                 if (strlen(buf) == 0) {
 421                         /* An empty metadata packet is OK. */
 422                         goto end;
 423                 }
 424
 425                 /* Convert the real file pointer to a memory file pointer */
 426                 fp = bt_fmemopen(buf, strlen(buf), "rb");
 427                 close_fp = true;
 428                 if (!fp) {
 429                         BT_LOGE("Cannot memory-open metadata buffer: %s: "
 430                                 "mdec-addr=%p", strerror(errno), mdec);
 431                         status = CTF_METADATA_DECODER_STATUS_ERROR;
 432                         goto end;
 433                 }
 434         } else {
 435                 unsigned int major, minor;
 436                 ssize_t nr_items;
 437                 const long init_pos = ftell(fp);
 438
 439                 BT_LOGD("Metadata stream is plain text: mdec-addr=%p", mdec);
 440
 441                 if (init_pos < 0) {
 442                         BT_LOGE_ERRNO("Failed to get current file position", ".");
 443                         status = CTF_METADATA_DECODER_STATUS_ERROR;
 444                         goto end;
 445                 }
 446
 447                 /* Check text-only metadata header and version */
 448                 nr_items = fscanf(fp, "/* CTF %10u.%10u", &major, &minor);
 449                 if (nr_items < 2) {
 450                         BT_LOGW("Missing \"/* CTF major.minor\" signature in plain text metadata file stream: "
 451                                 "mdec-addr=%p", mdec);
 452                 }
 453
 454                 BT_LOGD("Found metadata stream version in signature: version=%u.%u", major, minor);
 455
 456                 if (!is_version_valid(major, minor)) {
 457                         BT_LOGE("Invalid metadata version found in plain text signature: "
 458                                 "version=%u.%u, mdec-addr=%p", major, minor,
 459                                 mdec);
 460                         status = CTF_METADATA_DECODER_STATUS_INVAL_VERSION;
 461                         goto end;
 462                 }
 463
 464                 if (fseek(fp, init_pos, SEEK_SET)) {
 465                         BT_LOGE("Cannot seek metadata file stream to initial position: %s: "
 466                                 "mdec-addr=%p", strerror(errno), mdec);
 467                         status = CTF_METADATA_DECODER_STATUS_ERROR;
 468                         goto end;
 469                 }
 470         }
 471
 472         if (BT_LOG_ON_VERBOSE) {
 473                 yydebug = 1;
 474         }
 475
 476         /* Allocate a scanner and append the metadata text content */
 477         scanner = ctf_scanner_alloc();
 478         if (!scanner) {
 479                 BT_LOGE("Cannot allocate a metadata lexical scanner: "
 480                         "mdec-addr=%p", mdec);
 481                 status = CTF_METADATA_DECODER_STATUS_ERROR;
 482                 goto end;
 483         }
 484
 485         assert(fp);
 486         ret = ctf_scanner_append_ast(scanner, fp);
 487         if (ret) {
 488                 BT_LOGE("Cannot create the metadata AST out of the metadata text: "
 489                         "mdec-addr=%p", mdec);
 490                 status = CTF_METADATA_DECODER_STATUS_INCOMPLETE;
 491                 goto end;
 492         }
 493
 494         ret = ctf_visitor_semantic_check(0, &scanner->ast->root);
 495         if (ret) {
 496                 BT_LOGE("Validation of the metadata semantics failed: "
 497                         "mdec-addr=%p", mdec);
 498                 status = CTF_METADATA_DECODER_STATUS_ERROR;
 499                 goto end;
 500         }
 501
 502         ret = ctf_visitor_generate_ir_visit_node(mdec->visitor,
 503                 &scanner->ast->root);
 504         switch (ret) {
 505         case 0:
 506                 /* Success */
 507                 break;
 508         case -EINCOMPLETE:
 509                 BT_LOGD("While visiting metadata AST: incomplete data: "
 510                         "mdec-addr=%p", mdec);
 511                 status = CTF_METADATA_DECODER_STATUS_INCOMPLETE;
 512                 goto end;
 513         default:
 514                 BT_LOGE("Failed to visit AST node to create CTF IR objects: "
 515                         "mdec-addr=%p, ret=%d", mdec, ret);
 516                 status = CTF_METADATA_DECODER_STATUS_IR_VISITOR_ERROR;
 517                 goto end;
 518         }
 519
 520 end:
 521         if (scanner) {
 522                 ctf_scanner_free(scanner);
 523         }
 524
 525         yydebug = 0;
 526
 527         if (fp && close_fp) {
 528                 if (fclose(fp)) {
 529                         BT_LOGE("Cannot close metadata file stream: "
 530                                 "mdec-addr=%p", mdec);
 531                 }
 532         }
 533
 534         if (buf) {
 535                 free(buf);
 536         }
 537
 538         return status;
 539 }
 540
 541 BT_HIDDEN
 542 struct bt_ctf_trace *ctf_metadata_decoder_get_trace(
 543                 struct ctf_metadata_decoder *mdec)
 544 {
 545         return ctf_visitor_generate_ir_get_trace(mdec->visitor);
 546 }