dftest.c

   1 /* dftest.c
   2  * Shows display filter byte-code, for debugging dfilter routines.
   3  *
   4  * Wireshark - Network traffic analyzer
   5  * By Gerald Combs <gerald@wireshark.org>
   6  * Copyright 1998 Gerald Combs
   7  *
   8  * SPDX-License-Identifier: GPL-2.0-or-later
   9  */
  10
  11 #include <config.h>
  12 #define WS_LOG_DOMAIN  LOG_DOMAIN_MAIN
  13
  14 #include <stdlib.h>
  15 #include <stdio.h>
  16 #include <locale.h>
  17 #include <string.h>
  18 #include <errno.h>
  19
  20 #include <glib.h>
  21
  22 #include <ws_exit_codes.h>
  23
  24 #include <epan/epan.h>
  25 #include <epan/timestamp.h>
  26 #include <epan/prefs.h>
  27 #include <epan/dfilter/dfilter.h>
  28 #include <epan/dfilter/dfilter-macro.h>
  29
  30 #ifdef HAVE_PLUGINS
  31 #include <wsutil/plugins.h>
  32 #endif
  33 #include <wsutil/filesystem.h>
  34 #include <wsutil/privileges.h>
  35 #include <wsutil/report_message.h>
  36 #include <wsutil/wslog.h>
  37 #include <wsutil/ws_getopt.h>
  38 #include <wsutil/utf8_entities.h>
  39
  40 #include <wiretap/wtap.h>
  41
  42 #include "ui/util.h"
  43 #include "wsutil/cmdarg_err.h"
  44 #include "ui/failure_message.h"
  45 #include "wsutil/version_info.h"
  46
  47 static int opt_verbose;
  48 static int opt_debug_level; /* currently up to 2 */
  49 static int opt_flex;
  50 static int opt_lemon;
  51 static int opt_syntax_tree;
  52 static int opt_return_vals;
  53 static int opt_timer;
  54 static long opt_optimize = 1;
  55 static int opt_show_types;
  56 static int opt_dump_refs;
  57 static int opt_dump_macros;
  58
  59 static int64_t elapsed_expand;
  60 static int64_t elapsed_compile;
  61
  62 /*
  63  * Report an error in command-line arguments.
  64  */
  65 static void
  66 dftest_cmdarg_err(const char *fmt, va_list ap)
  67 {
  68     fprintf(stderr, "dftest: ");
  69     vfprintf(stderr, fmt, ap);
  70     fprintf(stderr, "\n");
  71 }
  72
  73 /*
  74  * Report additional information for an error in command-line arguments.
  75  */
  76 static void
  77 dftest_cmdarg_err_cont(const char *fmt, va_list ap)
  78 {
  79     vfprintf(stderr, fmt, ap);
  80     fprintf(stderr, "\n");
  81 }
  82
  83 static void
  84 putloc(FILE *fp, df_loc_t loc)
  85 {
  86     for (long i = 0; i < loc.col_start; i++) {
  87         fputc(' ', fp);
  88     }
  89     fputc('^', fp);
  90
  91     for (size_t l = loc.col_len; l > 1; l--) {
  92         fputc('~', fp);
  93     }
  94     fputc('\n', fp);
  95 }
  96
  97 WS_NORETURN static void
  98 print_usage(int status)
  99 {
 100     FILE *fp = stdout;
 101     fprintf(fp, "\n");
 102     fprintf(fp, "Usage: dftest [OPTIONS] -- EXPRESSION\n");
 103     fprintf(fp, "Options:\n");
 104     fprintf(fp, "  -V, --verbose       enable verbose mode\n");
 105     fprintf(fp, "  -d, --debug[=N]     increase or set debug level\n");
 106     fprintf(fp, "  -D                  set maximum debug level\n");
 107     fprintf(fp, "  -f, --flex          enable Flex debug trace\n");
 108     fprintf(fp, "  -l, --lemon         enable Lemon debug trace\n");
 109     fprintf(fp, "  -s, --syntax        print syntax tree\n");
 110     fprintf(fp, "  -m  --macros        print saved macros\n");
 111     fprintf(fp, "  -t, --timer         print elapsed compilation time\n");
 112     fprintf(fp, "  -r  --return-vals   return field values for the tree root\n");
 113     fprintf(fp, "  -0, --optimize=0    do not optimize (check syntax)\n");
 114     fprintf(fp, "      --types         show field value types\n");
 115     /* NOTE: References are loaded during runtime and dftest only does compilation.
 116      * Unless some static reference data is hard-coded at compile time during
 117      * development the --refs option to dftest is useless because it will just
 118      * print empty reference vectors. */
 119     fprintf(fp, "      --refs          dump some runtime data structures\n");
 120     fprintf(fp, "  -h, --help          display this help and exit\n");
 121     fprintf(fp, "  -v, --version       print version\n");
 122     fprintf(fp, "\n");
 123     ws_log_print_usage(fp);
 124     exit(status);
 125 }
 126
 127 static void
 128 print_syntax_tree(dfilter_t *df)
 129 {
 130     printf("Syntax tree:\n%s\n\n", dfilter_syntax_tree(df));
 131 }
 132
 133 static void
 134 print_macros(void)
 135 {
 136     if (dfilter_macro_table_count() == 0) {
 137         printf("Macros: (empty)\n\n");
 138         return;
 139     }
 140
 141     struct dfilter_macro_table_iter iter;
 142     const char *name, *text;
 143
 144     dfilter_macro_table_iter_init(&iter);
 145     printf("Macros:\n");
 146     while (dfilter_macro_table_iter_next(&iter, &name, &text)) {
 147         printf(" "UTF8_BULLET" %s:\n", name);
 148         printf("      %s\n", text);
 149     }
 150     printf("\n");
 151 }
 152
 153 static void
 154 print_warnings(dfilter_t *df)
 155 {
 156     unsigned i;
 157     GPtrArray *deprecated;
 158     int count = 0;
 159
 160     for (GSList *l = dfilter_get_warnings(df); l != NULL; l = l->next) {
 161         printf("\nWarning: %s.", (char *)l->data);
 162         count++;
 163     }
 164
 165     deprecated = dfilter_deprecated_tokens(df);
 166     if (deprecated && deprecated->len) {
 167         for (i = 0; i < deprecated->len; i++) {
 168             const char *token = g_ptr_array_index(deprecated, i);
 169             printf("\nWarning: Deprecated token \"%s\".", token);
 170             count++;
 171         }
 172     }
 173
 174     if (count) {
 175         printf("\n");
 176     }
 177 }
 178
 179 static void
 180 print_elapsed(void)
 181 {
 182     printf("\nElapsed: %"PRId64" µs (%"PRId64" µs + %"PRId64" µs)\n",
 183             elapsed_expand + elapsed_compile,
 184             elapsed_expand,
 185             elapsed_compile);
 186 }
 187
 188 static char *
 189 expand_filter(const char *text)
 190 {
 191     char *expanded = NULL;
 192     df_error_t *err = NULL;
 193     int64_t start;
 194
 195     start = g_get_monotonic_time();
 196     expanded = dfilter_expand(text, &err);
 197     if (expanded == NULL) {
 198         fprintf(stderr, "Error: %s\n", err->msg);
 199         df_error_free(&err);
 200     }
 201     elapsed_expand = g_get_monotonic_time() - start;
 202     return expanded;
 203 }
 204
 205 static bool
 206 compile_filter(const char *text, dfilter_t **dfp)
 207 {
 208     unsigned df_flags = 0;
 209     bool ok;
 210     df_error_t *df_err = NULL;
 211     int64_t start;
 212
 213     if (opt_optimize > 0)
 214         df_flags |= DF_OPTIMIZE;
 215     if (opt_syntax_tree)
 216         df_flags |= DF_SAVE_TREE;
 217     if (opt_flex)
 218         df_flags |= DF_DEBUG_FLEX;
 219     if (opt_lemon)
 220         df_flags |= DF_DEBUG_LEMON;
 221     if (opt_return_vals)
 222         df_flags |= DF_RETURN_VALUES;
 223
 224     start = g_get_monotonic_time();
 225     ok = dfilter_compile_full(text, dfp, &df_err, df_flags, "dftest");
 226     if (!ok) {
 227         fprintf(stderr, "Error: %s\n", df_err->msg);
 228         if (df_err->loc.col_start >= 0) {
 229             fprintf(stderr, "  %s\n  ", text);
 230             putloc(stderr, df_err->loc);
 231         }
 232         df_error_free(&df_err);
 233     }
 234     elapsed_compile = g_get_monotonic_time() - start;
 235     return ok;
 236 }
 237
 238 static int
 239 optarg_to_digit(const char *arg)
 240 {
 241     if (strlen(arg) > 1 || !g_ascii_isdigit(*arg)) {
 242         printf("Error: \"%s\" is not a valid number 0-9\n", arg);
 243         print_usage(WS_EXIT_INVALID_OPTION);
 244     }
 245     errno = 0;
 246     int digit = (int)strtol(ws_optarg, NULL, 10);
 247     if (errno) {
 248         printf("Error: %s\n", g_strerror(errno));
 249         print_usage(WS_EXIT_INVALID_OPTION);
 250     }
 251     return digit;
 252 }
 253
 254 int
 255 main(int argc, char **argv)
 256 {
 257     char                *configuration_init_error;
 258     char        *text = NULL;
 259     char        *expanded_text = NULL;
 260     dfilter_t   *df = NULL;
 261     int          exit_status = EXIT_FAILURE;
 262
 263     /*
 264      * Set the C-language locale to the native environment and set the
 265      * code page to UTF-8 on Windows.
 266      */
 267 #ifdef _WIN32
 268     setlocale(LC_ALL, ".UTF-8");
 269 #else
 270     setlocale(LC_ALL, "");
 271 #endif
 272
 273     cmdarg_err_init(dftest_cmdarg_err, dftest_cmdarg_err_cont);
 274
 275     /* Initialize log handler early for startup. */
 276     ws_log_init("dftest", vcmdarg_err);
 277
 278     /* Early logging command-line initialization. */
 279     ws_log_parse_args(&argc, argv, vcmdarg_err, 1);
 280
 281     ws_noisy("Finished log init and parsing command line log arguments");
 282
 283     ws_init_version_info("DFTest", NULL, NULL);
 284
 285     const char *optstring = "hvdDflsmrtV0";
 286     static struct ws_option long_options[] = {
 287         { "help",     ws_no_argument,   0,  'h' },
 288         { "version",  ws_no_argument,   0,  'v' },
 289         { "debug",    ws_optional_argument, 0, 'd' },
 290         { "flex",     ws_no_argument,   0,  'f' },
 291         { "lemon",    ws_no_argument,   0,  'l' },
 292         { "syntax",   ws_no_argument,   0,  's' },
 293         { "macros",   ws_no_argument,   0,  'm' },
 294         { "timer",    ws_no_argument,   0,  't' },
 295         { "verbose",  ws_no_argument,   0,  'V' },
 296         { "return-vals", ws_no_argument,   0,  'r' },
 297         { "optimize", ws_required_argument, 0, 1000 },
 298         { "types",    ws_no_argument,   0, 2000 },
 299         { "refs",     ws_no_argument,   0, 3000 },
 300         { NULL,       0,                0,  0   }
 301     };
 302     int opt;
 303
 304     for (;;) {
 305         opt = ws_getopt_long(argc, argv, optstring, long_options, NULL);
 306         if (opt == -1)
 307             break;
 308
 309         switch (opt) {
 310             case 'V':
 311                 opt_verbose = 1;
 312                 break;
 313             case 'd':
 314                 if (ws_optarg) {
 315                     opt_debug_level = optarg_to_digit(ws_optarg);
 316                 }
 317                 else {
 318                     opt_debug_level++;
 319                 }
 320                 opt_show_types = 1;
 321                 break;
 322             case 'D':
 323                 opt_debug_level = 9;
 324                 opt_lemon = 1;
 325                 opt_flex = 1;
 326                 opt_show_types = 1;
 327                 break;
 328             case 'f':
 329                 opt_flex = 1;
 330                 break;
 331             case 'l':
 332                 opt_lemon = 1;
 333                 break;
 334             case 's':
 335                 opt_syntax_tree = 1;
 336                 break;
 337             case 'm':
 338                 opt_dump_macros = 1;
 339                 break;
 340             case 't':
 341                 opt_timer = 1;
 342                 break;
 343             case 'r':
 344                 opt_return_vals = 1;
 345                 break;
 346             case '0':
 347                 opt_optimize = 0;
 348                 break;
 349             case 1000:
 350                 opt_optimize = optarg_to_digit(ws_optarg);
 351                 break;
 352             case 2000:
 353                 opt_show_types = 1;
 354                 break;
 355             case 3000:
 356                 opt_dump_refs = 1;
 357                 break;
 358             case 'v':
 359                 show_version();
 360                 exit(EXIT_SUCCESS);
 361                 break;
 362             case 'h':
 363                 show_help_header(NULL);
 364                 print_usage(EXIT_SUCCESS);
 365                 break;
 366             case '?':
 367                 print_usage(EXIT_FAILURE);
 368             default:
 369                 ws_assert_not_reached();
 370         }
 371     }
 372
 373     /* Check for filter on command line. */
 374     if (argv[ws_optind] == NULL) {
 375         /* If not printing macros we need a filter expression to compile. */
 376         if (!opt_dump_macros) {
 377             printf("Error: Missing argument.\n");
 378             print_usage(EXIT_FAILURE);
 379         }
 380     }
 381
 382     /* Set dfilter domain logging. */
 383     if (opt_debug_level > 1) {
 384         ws_log_set_noisy_filter(LOG_DOMAIN_DFILTER);
 385     }
 386     else if (opt_debug_level > 0 || opt_flex || opt_lemon) {
 387         /* Also enable some dfilter logs with flex/lemon traces for context. */
 388         ws_log_set_debug_filter(LOG_DOMAIN_DFILTER);
 389     }
 390
 391     /*
 392      * Get credential information for later use.
 393      */
 394     init_process_policies();
 395
 396     /*
 397      * Attempt to get the pathname of the directory containing the
 398      * executable file.
 399      */
 400     configuration_init_error = configuration_init(argv[0], NULL);
 401     if (configuration_init_error != NULL) {
 402         fprintf(stderr, "Error: Can't get pathname of directory containing "
 403                         "the dftest program: %s.\n",
 404             configuration_init_error);
 405         g_free(configuration_init_error);
 406     }
 407
 408     static const struct report_message_routines dftest_report_routines = {
 409         failure_message,
 410         failure_message,
 411         open_failure_message,
 412         read_failure_message,
 413         write_failure_message,
 414         cfile_open_failure_message,
 415         cfile_dump_open_failure_message,
 416         cfile_read_failure_message,
 417         cfile_write_failure_message,
 418         cfile_close_failure_message
 419     };
 420
 421     init_report_message("dftest", &dftest_report_routines);
 422
 423     timestamp_set_type(TS_RELATIVE);
 424     timestamp_set_seconds_type(TS_SECONDS_DEFAULT);
 425
 426     /*
 427      * Libwiretap must be initialized before libwireshark is, so that
 428      * dissection-time handlers for file-type-dependent blocks can
 429      * register using the file type/subtype value for the file type.
 430      */
 431     wtap_init(true);
 432
 433     /* Register all dissectors; we must do this before checking for the
 434        "-g" flag, as the "-g" flag dumps a list of fields registered
 435        by the dissectors, and we must do it before we read the preferences,
 436        in case any dissectors register preferences. */
 437     if (!epan_init(NULL, NULL, true))
 438         goto out;
 439
 440     /* Load libwireshark settings from the current profile. */
 441     epan_load_settings();
 442
 443     /* notify all registered modules that have had any of their preferences
 444        changed either from one of the preferences file or from the command
 445        line that its preferences have changed. */
 446     prefs_apply_all();
 447
 448     if (opt_dump_macros) {
 449         print_macros();
 450         if (argv[ws_optind] == NULL) {
 451             /* No filter expression, we're done. */
 452             exit(EXIT_SUCCESS);
 453         }
 454     }
 455
 456     /* Check again for filter on command line */
 457     if (argv[ws_optind] == NULL) {
 458         printf("Error: Missing argument.\n");
 459         print_usage(EXIT_FAILURE);
 460     }
 461
 462     /* This is useful to prevent confusion with option parsing.
 463      * Skips printing options and argv[0]. */
 464     if (opt_verbose) {
 465         for (int i = ws_optind; i < argc; i++) {
 466             fprintf(stderr, "argv[%d]: %s\n", i, argv[i]);
 467         }
 468         fprintf(stderr, "\n");
 469     }
 470
 471     /* Get filter text */
 472     text = get_args_as_string(argc, argv, ws_optind);
 473
 474     printf("Filter:\n %s\n\n", text);
 475
 476     /* Expand macros. */
 477     expanded_text = expand_filter(text);
 478     if (expanded_text == NULL) {
 479         exit_status = WS_EXIT_INVALID_FILTER;
 480         goto out;
 481     }
 482
 483     if (strcmp(text, expanded_text) != 0)
 484         printf("Filter (after expansion):\n %s\n\n", expanded_text);
 485
 486     /* Compile it */
 487     if (!compile_filter(expanded_text, &df)) {
 488         exit_status = WS_EXIT_INVALID_FILTER;
 489         goto out;
 490     }
 491
 492     /* If logging is enabled add an empty line. */
 493     if (opt_debug_level > 0) {
 494         printf("\n");
 495     }
 496
 497     if (df == NULL) {
 498         printf("Filter is empty.\n");
 499         exit_status = WS_EXIT_INVALID_FILTER;
 500         goto out;
 501     }
 502
 503     if (opt_syntax_tree)
 504         print_syntax_tree(df);
 505
 506     uint16_t dump_flags = 0;
 507     if (opt_show_types)
 508         dump_flags |= DF_DUMP_SHOW_FTYPE;
 509     if (opt_dump_refs)
 510         dump_flags |= DF_DUMP_REFERENCES;
 511
 512     dfilter_dump(stdout, df, dump_flags);
 513
 514     print_warnings(df);
 515
 516     if (opt_timer)
 517         print_elapsed();
 518
 519     exit_status = 0;
 520
 521 out:
 522     epan_cleanup();
 523     dfilter_free(df);
 524     g_free(text);
 525     g_free(expanded_text);
 526     exit(exit_status);
 527 }