src/md5sum.c

   1 /* Compute MD5 checksum of files or strings according to the definition
   2    of MD5 in RFC 1321 from April 1992.
   3    Copyright (C) 1995 Free Software Foundation, Inc.
   4
   5    This program is free software; you can redistribute it and/or modify
   6    it under the terms of the GNU General Public License as published by
   7    the Free Software Foundation; either version 2, or (at your option)
   8    any later version.
   9
  10    This program is distributed in the hope that it will be useful,
  11    but WITHOUT ANY WARRANTY; without even the implied warranty of
  12    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  13    GNU General Public License for more details.
  14
  15    You should have received a copy of the GNU General Public License
  16    along with this program; if not, write to the Free Software Foundation,
  17    Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.  */
  18
  19 /* Written by Ulrich Drepper <drepper@gnu.ai.mit.edu>.  */
  20
  21 #ifdef HAVE_CONFIG_H
  22 # include <config.h>
  23 #endif
  24
  25 #include <getopt.h>
  26 #include <stdio.h>
  27 #include <sys/types.h>
  28
  29 #include "long-options.h"
  30 #include "md5.h"
  31 #include "getline.h"
  32 #include "system.h"
  33 #include "error.h"
  34 #include "version.h"
  35
  36 /* Most systems do not distinguish between external and internal
  37    text representations.  */
  38 #if UNIX || __UNIX__ || unix || __unix__ || _POSIX_VERSION
  39 # define OPENOPTS(BINARY) "r"
  40 #else
  41 # ifdef MSDOS
  42 #  define TEXT1TO1 "rb"
  43 #  define TEXTCNVT "r"
  44 # else
  45 #  if defined VMS
  46 #   define TEXT1TO1 "rb", "ctx=stm"
  47 #   define TEXTCNVT "r", "ctx=stm"
  48 #  else
  49     /* The following line is intended to evoke an error.
  50        Using #error is not portable enough.  */
  51     "Cannot determine system type."
  52 #  endif
  53 # endif
  54 # define OPENOPTS(BINARY) ((BINARY) != 0 ? TEXT1TO1 : TEXTCNVT)
  55 #endif
  56
  57 #if _LIBC || STDC_HEADERS
  58 # define TOLOWER(c) tolower (c)
  59 #else
  60 # define TOLOWER(c) (ISUPPER (c) ? tolower (c) : (c))
  61 #endif
  62
  63 /* Nonzero if any of the files read were the standard input. */
  64 static int have_read_stdin;
  65
  66 /* With --check, don't generate any output.
  67    The exit code indicates success or failure.  */
  68 static int status_only = 0;
  69
  70 /* With --check, print a message to standard error warning about each
  71    improperly formatted MD5 checksum line.  */
  72 static int warn = 0;
  73
  74 /* The name this program was run with.  */
  75 char *program_name;
  76
  77 static const struct option long_options[] =
  78 {
  79   { "binary", no_argument, 0, 'b' },
  80   { "check", no_argument, 0, 'c' },
  81   { "status", no_argument, 0, 2 },
  82   { "string", required_argument, 0, 1 },
  83   { "text", no_argument, 0, 't' },
  84   { "warn", no_argument, 0, 'w' },
  85   { NULL, 0, NULL, 0 }
  86 };
  87
  88 char *xmalloc ();
  89
  90 static void
  91 usage (int status)
  92 {
  93   if (status != 0)
  94     fprintf (stderr, _("Try `%s --help' for more information.\n"),
  95              program_name);
  96   else
  97     printf (_("\
  98 Usage: %s [OPTION] [FILE]...\n\
  99   or:  %s [OPTION] --check [FILE]\n\
 100   or:  %s [OPTION] --string=STRING ...\n\
 101 Print or check MD5 checksums.\n\
 102 With no FILE, or when FILE is -, read standard input.\n\
 103 \n\
 104   -b, --binary            read files in binary mode\n\
 105   -t, --text              read files in text mode (default)\n\
 106   -c, --check             check MD5 sums against given list\n\
 107 \n\
 108 The following two options are useful only when verifying checksums:\n\
 109       --status            don't output anything, status code shows success\n\
 110   -w, --warn              warn about improperly formated MD5 checksum lines\n\
 111 \n\
 112       --string=STRING     compute checksum for STRING\n\
 113       --help              display this help and exit\n\
 114       --version           output version information and exit\n\
 115 \n\
 116 The sums are computed as described in RFC 1321.  When checking, the input\n\
 117 should be a former output of this program.  The default mode is to print\n\
 118 a line with checksum, a character indicating type (`*' for binary, ` ' for\n\
 119 text), and name for each FILE.\n"),
 120             program_name, program_name, program_name);
 121
 122   exit (status);
 123 }
 124
 125 /* FIXME: this format loses with filenames containing newline.  */
 126
 127 static int
 128 split_3 (char *s, char **u, int *binary, char **w)
 129 {
 130   size_t i;
 131
 132 #define ISWHITE(c) ((c) == ' ' || (c) == '\t')
 133
 134   i = 0;
 135   while (ISWHITE (s[i]))
 136     ++i;
 137
 138   /* The line has to be at least 35 characters long to contain correct
 139      message digest information.  */
 140   if (strlen (&s[i]) >= 35)
 141     {
 142       *u = &s[i];
 143
 144       /* The first field has to be the 32-character hexadecimal
 145          representation of the message digest.  If it not immediately
 146          followed by a white space it's an error.  */
 147       i += 32;
 148       if (!ISWHITE (s[i]))
 149         return 1;
 150
 151       s[i++] = '\0';
 152
 153       if (s[i] != ' ' && s[i] != '*')
 154         return 1;
 155       *binary = s[i++] == '*';
 156
 157       /* All characters between the type indicator and end of line are
 158          significant -- that includes leading and trailing white space.  */
 159       *w = &s[i];
 160
 161       /* So this line is valid as long as there is at least one character
 162          for the filename.  */
 163       return (**w ? 0 : 1);
 164     }
 165   return 1;
 166 }
 167
 168 static int
 169 hex_digits (const char *s)
 170 {
 171   while (*s)
 172     {
 173       if (!ISXDIGIT (*s))
 174         return 0;
 175       ++s;
 176     }
 177   return 1;
 178 }
 179
 180 /* FIXME: allow newline in filename by encoding it. */
 181
 182 static int
 183 md5_file (const char *filename, int binary, unsigned char *md5_result)
 184 {
 185   FILE *fp;
 186   int err;
 187
 188   if (strcmp (filename, "-") == 0)
 189     {
 190       have_read_stdin = 1;
 191       fp = stdin;
 192     }
 193   else
 194     {
 195       /* OPENOPTS is a macro.  It varies with the system.
 196          Some systems distinguish between internal and
 197          external text representations.  */
 198
 199       fp = fopen (filename, OPENOPTS (binary));
 200       if (fp == NULL)
 201         {
 202           error (0, errno, "%s", filename);
 203           return 1;
 204         }
 205     }
 206
 207   err = md5_stream (fp, md5_result);
 208   if (err)
 209     {
 210       error (0, errno, "%s", filename);
 211       if (fp != stdin)
 212         fclose (fp);
 213       return 1;
 214     }
 215
 216   if (fp != stdin && fclose (fp) == EOF)
 217     {
 218       error (0, errno, "%s", filename);
 219       return 1;
 220     }
 221
 222   return 0;
 223 }
 224
 225 static int
 226 md5_check (const char *checkfile_name, int binary)
 227 {
 228   FILE *checkfile_stream;
 229   int n_properly_formated_lines = 0;
 230   int n_mismatched_checksums = 0;
 231   int n_open_or_read_failures = 0;
 232   unsigned char md5buffer[16];
 233   size_t line_number;
 234   char *line;
 235   size_t line_chars_allocated;
 236
 237   if (strcmp (checkfile_name, "-") == 0)
 238     {
 239       have_read_stdin = 1;
 240       checkfile_name = _("standard input");
 241       checkfile_stream = stdin;
 242     }
 243   else
 244     {
 245       checkfile_stream = fopen (checkfile_name, "r");
 246       if (checkfile_stream == NULL)
 247         {
 248           error (0, errno, "%s", checkfile_name);
 249           return 1;
 250         }
 251     }
 252
 253   line_number = 0;
 254   line = NULL;
 255   line_chars_allocated = 0;
 256   do
 257     {
 258       char *filename;
 259       int type_flag;
 260       char *md5num;
 261       int err;
 262       int line_length;
 263
 264       ++line_number;
 265
 266       line_length = getline (&line, &line_chars_allocated, checkfile_stream);
 267       if (line_length <= 0)
 268         break;
 269
 270       /* Ignore comment lines, which begin with a '#' character.  */
 271       if (line[0] == '#')
 272         continue;
 273
 274       /* Remove any trailing newline.  */
 275       if (line[line_length - 1] == '\n')
 276         line[--line_length] = '\0';
 277
 278       err = split_3 (line, &md5num, &type_flag, &filename);
 279       if (err || !hex_digits (md5num))
 280         {
 281           if (warn)
 282             {
 283               error (0, 0,
 284                      _("%s: %lu: improperly formatted MD5 checksum line"),
 285                      checkfile_name, (unsigned long) line_number);
 286             }
 287         }
 288       else
 289         {
 290           static const char bin2hex[] = { '0', '1', '2', '3',
 291                                           '4', '5', '6', '7',
 292                                           '8', '9', 'a', 'b',
 293                                           'c', 'd', 'e', 'f' };
 294           int fail;
 295
 296           ++n_properly_formated_lines;
 297
 298           fail = md5_file (filename, binary, md5buffer);
 299
 300           if (fail)
 301             {
 302               ++n_open_or_read_failures;
 303               if (!status_only)
 304                 {
 305                   printf (_("%s: FAILED open or read\n"), filename);
 306                   fflush (stdout);
 307                 }
 308             }
 309           else
 310             {
 311               size_t cnt;
 312               /* Compare generated binary number with text representation
 313                  in check file.  Ignore case of hex digits.  */
 314               for (cnt = 0; cnt < 16; ++cnt)
 315                 {
 316                   if (TOLOWER (md5num[2 * cnt]) != bin2hex[md5buffer[cnt] >> 4]
 317                       || (TOLOWER (md5num[2 * cnt + 1])
 318                           != (bin2hex[md5buffer[cnt] & 0xf])))
 319                     break;
 320                 }
 321               if (cnt != 16)
 322                 ++n_mismatched_checksums;
 323
 324               if (!status_only)
 325                 {
 326                   printf ("%s: %s\n", filename,
 327                           (cnt != 16 ? _("FAILED") : _("OK")));
 328                   fflush (stdout);
 329                 }
 330             }
 331         }
 332     }
 333   while (!feof (checkfile_stream) && !ferror (checkfile_stream));
 334
 335   if (line)
 336     free (line);
 337
 338   if (ferror (checkfile_stream))
 339     {
 340       error (0, 0, _("%s: read error"), checkfile_name);
 341       return 1;
 342     }
 343
 344   if (checkfile_stream != stdin && fclose (checkfile_stream) == EOF)
 345     {
 346       error (0, errno, "%s", checkfile_name);
 347       return 1;
 348     }
 349
 350   if (n_properly_formated_lines == 0)
 351     {
 352       /* Warn if no tests are found.  */
 353       error (0, 0, _("%s: no properly formatted MD5 checksum lines found"),
 354              checkfile_name);
 355     }
 356   else
 357     {
 358       if (!status_only)
 359         {
 360           int n_computed_checkums = (n_properly_formated_lines
 361                                      - n_open_or_read_failures);
 362
 363           if (n_open_or_read_failures > 0)
 364             {
 365               error (0, 0,
 366                    _("WARNING: %d of %d listed file%s could not be read\n"),
 367                      n_open_or_read_failures, n_properly_formated_lines,
 368                      (n_properly_formated_lines == 1 ? "" : "s"));
 369             }
 370
 371           if (n_mismatched_checksums > 0)
 372             {
 373               error (0, 0,
 374                    _("WARNING: %d of %d computed checksum%s did NOT match\n"),
 375                      n_mismatched_checksums, n_computed_checkums,
 376                      (n_computed_checkums == 1 ? "" : "s"));
 377             }
 378         }
 379     }
 380
 381   return ((n_properly_formated_lines > 0 && n_mismatched_checksums == 0
 382            && n_open_or_read_failures == 0) ? 0 : 1);
 383 }
 384
 385 int
 386 main (int argc, char **argv)
 387 {
 388   unsigned char md5buffer[16];
 389   int do_check = 0;
 390   int do_version = 0;
 391   int opt;
 392   char **string = NULL;
 393   size_t n_strings = 0;
 394   size_t i;
 395   size_t err = 0;
 396
 397   /* Text is default of the Plumb/Lankester format.  */
 398   int binary = 0;
 399
 400   /* Setting values of global variables.  */
 401   program_name = argv[0];
 402   setlocale (LC_ALL, "");
 403   bindtextdomain (PACKAGE, LOCALEDIR);
 404   textdomain (PACKAGE);
 405
 406   parse_long_options (argc, argv, "md5sum", version_string, usage);
 407
 408   while ((opt = getopt_long (argc, argv, "bctw", long_options, NULL))
 409          != EOF)
 410     switch (opt)
 411       {
 412       case 0:                   /* long option */
 413         break;
 414       case 1: /* --string */
 415         {
 416           if (string == NULL)
 417             string = (char **) xmalloc ((argc - 1) * sizeof (char *));
 418
 419           if (optarg == NULL)
 420             optarg = "";
 421           string[n_strings++] = optarg;
 422         }
 423         break;
 424       case 'b':
 425         binary = 1;
 426         break;
 427       case 'c':
 428         do_check = 1;
 429         break;
 430       case 2:
 431         status_only = 1;
 432         warn = 0;
 433         break;
 434       case 't':
 435         binary = 0;
 436         break;
 437       case 'w':
 438         status_only = 0;
 439         warn = 1;
 440         break;
 441       default:
 442         usage (EXIT_FAILURE);
 443       }
 444
 445   if (do_version)
 446     {
 447       printf ("md5sum - %s\n", version_string);
 448       exit (EXIT_SUCCESS);
 449     }
 450
 451   if (n_strings > 0 && do_check)
 452     {
 453       error (0, 0,
 454              _("the --string and --check options are mutually exclusive"));
 455       usage (EXIT_FAILURE);
 456     }
 457
 458   if (status_only && !do_check)
 459     {
 460       error (0, 0,
 461        _("the --status option is meaningful only when verifying checksums"));
 462       usage (EXIT_FAILURE);
 463     }
 464
 465   if (warn && !do_check)
 466     {
 467       error (0, 0,
 468        _("the --warn option is meaningful only when verifying checksums"));
 469       usage (EXIT_FAILURE);
 470     }
 471
 472   if (n_strings > 0)
 473     {
 474       if (optind < argc)
 475         {
 476           error (0, 0, _("no files may be specified when using --string"));
 477           usage (EXIT_FAILURE);
 478         }
 479       for (i = 0; i < n_strings; ++i)
 480         {
 481           size_t cnt;
 482           md5_buffer (string[i], strlen (string[i]), md5buffer);
 483
 484           for (cnt = 0; cnt < 16; ++cnt)
 485             printf ("%02x", md5buffer[cnt]);
 486
 487           printf ("  \"%s\"\n", string[i]);
 488         }
 489     }
 490   else if (do_check)
 491     {
 492       if (optind + 1 < argc)
 493         {
 494           error (0, 0,
 495                  _("only one argument may be specified when using --check"));
 496           usage (EXIT_FAILURE);
 497         }
 498
 499       err = md5_check ((optind == argc) ? "-" : argv[optind], binary);
 500     }
 501   else
 502     {
 503       if (optind == argc)
 504         argv[argc++] = "-";
 505
 506       for (; optind < argc; ++optind)
 507         {
 508           size_t i;
 509           int fail;
 510
 511           fail = md5_file (argv[optind], binary, md5buffer);
 512           err |= fail;
 513           if (!fail)
 514             {
 515               for (i = 0; i < 16; ++i)
 516                 printf ("%02x", md5buffer[i]);
 517
 518               printf (" %c%s\n", binary ? '*' : ' ', argv[optind]);
 519             }
 520         }
 521     }
 522
 523   if (fclose (stdout) == EOF)
 524     error (EXIT_FAILURE, errno, _("write error"));
 525
 526   if (have_read_stdin && fclose (stdin) == EOF)
 527     error (EXIT_FAILURE, errno, _("standard input"));
 528
 529   exit (err == 0 ? EXIT_SUCCESS : EXIT_FAILURE);
 530 }