grub-core/commands/hashsum.c

   1 /*
   2  *  GRUB  --  GRand Unified Bootloader
   3  *  Copyright (C) 2009  Free Software Foundation, Inc.
   4  *
   5  *  GRUB 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 3 of the License, or
   8  *  (at your option) any later version.
   9  *
  10  *  GRUB 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 GRUB.  If not, see <http://www.gnu.org/licenses/>.
  17  */
  18
  19 #include <grub/dl.h>
  20 #include <grub/extcmd.h>
  21 #include <grub/file.h>
  22 #include <grub/disk.h>
  23 #include <grub/mm.h>
  24 #include <grub/misc.h>
  25 #include <grub/crypto.h>
  26 #include <grub/normal.h>
  27 #include <grub/i18n.h>
  28
  29 GRUB_MOD_LICENSE ("GPLv3+");
  30
  31 static const struct grub_arg_option options[] = {
  32   {"hash", 'h', 0, N_("Specify hash to use."), N_("HASH"), ARG_TYPE_STRING},
  33   {"check", 'c', 0, N_("Check hashes of files with hash list FILE."),
  34    N_("FILE"), ARG_TYPE_STRING},
  35   {"prefix", 'p', 0, N_("Base directory for hash list."), N_("DIR"),
  36    ARG_TYPE_STRING},
  37   {"keep-going", 'k', 0, N_("Don't stop after first error."), 0, 0},
  38   {"uncompress", 'u', 0, N_("Uncompress file before checksumming."), 0, 0},
  39   {0, 0, 0, 0, 0, 0}
  40 };
  41
  42 static struct { const char *name; const char *hashname; } aliases[] =
  43   {
  44     {"sha256sum", "sha256"},
  45     {"sha512sum", "sha512"},
  46     {"sha1sum", "sha1"},
  47     {"md5sum", "md5"},
  48     {"crc", "crc32"},
  49   };
  50
  51 static inline int
  52 hextoval (char c)
  53 {
  54   if (c >= '0' && c <= '9')
  55     return c - '0';
  56   if (c >= 'a' && c <= 'f')
  57     return c - 'a' + 10;
  58   if (c >= 'A' && c <= 'F')
  59     return c - 'A' + 10;
  60   return -1;
  61 }
  62
  63 static grub_err_t
  64 hash_file (grub_file_t file, const gcry_md_spec_t *hash, void *result)
  65 {
  66   void *context;
  67   grub_uint8_t *readbuf;
  68 #define BUF_SIZE 4096
  69   readbuf = grub_malloc (BUF_SIZE);
  70   if (!readbuf)
  71     return grub_errno;
  72   context = grub_zalloc (hash->contextsize);
  73   if (!readbuf || !context)
  74     goto fail;
  75
  76   hash->init (context);
  77   while (1)
  78     {
  79       grub_ssize_t r;
  80       r = grub_file_read (file, readbuf, BUF_SIZE);
  81       if (r < 0)
  82         goto fail;
  83       if (r == 0)
  84         break;
  85       hash->write (context, readbuf, r);
  86     }
  87   hash->final (context);
  88   grub_memcpy (result, hash->read (context), hash->mdlen);
  89
  90   grub_free (readbuf);
  91   grub_free (context);
  92
  93   return GRUB_ERR_NONE;
  94
  95  fail:
  96   grub_free (readbuf);
  97   grub_free (context);
  98   return grub_errno;
  99 }
 100
 101 static grub_err_t
 102 check_list (const gcry_md_spec_t *hash, const char *hashfilename,
 103             const char *prefix, int keep, int uncompress)
 104 {
 105   grub_file_t hashlist, file;
 106   char *buf = NULL;
 107   grub_uint8_t expected[GRUB_CRYPTO_MAX_MDLEN];
 108   grub_uint8_t actual[GRUB_CRYPTO_MAX_MDLEN];
 109   grub_err_t err;
 110   unsigned i;
 111   unsigned unread = 0, mismatch = 0;
 112
 113   if (hash->mdlen > GRUB_CRYPTO_MAX_MDLEN)
 114     return grub_error (GRUB_ERR_BUG, "mdlen is too long");
 115
 116   hashlist = grub_file_open (hashfilename);
 117   if (!hashlist)
 118     return grub_errno;
 119
 120   while (grub_free (buf), (buf = grub_file_getline (hashlist)))
 121     {
 122       const char *p = buf;
 123       while (grub_isspace (p[0]))
 124         p++;
 125       for (i = 0; i < hash->mdlen; i++)
 126         {
 127           int high, low;
 128           high = hextoval (*p++);
 129           low = hextoval (*p++);
 130           if (high < 0 || low < 0)
 131             return grub_error (GRUB_ERR_BAD_FILE_TYPE, "invalid hash list");
 132           expected[i] = (high << 4) | low;
 133         }
 134       if ((p[0] != ' ' && p[0] != '\t') || (p[1] != ' ' && p[1] != '\t'))
 135         return grub_error (GRUB_ERR_BAD_FILE_TYPE, "invalid hash list");
 136       p += 2;
 137       if (prefix)
 138         {
 139           char *filename;
 140
 141           filename = grub_xasprintf ("%s/%s", prefix, p);
 142           if (!filename)
 143             return grub_errno;
 144           if (!uncompress)
 145             grub_file_filter_disable_compression ();
 146           file = grub_file_open (filename);
 147           grub_free (filename);
 148         }
 149       else
 150         {
 151           if (!uncompress)
 152             grub_file_filter_disable_compression ();
 153           file = grub_file_open (p);
 154         }
 155       if (!file)
 156         {
 157           grub_file_close (hashlist);
 158           grub_free (buf);
 159           return grub_errno;
 160         }
 161       err = hash_file (file, hash, actual);
 162       grub_file_close (file);
 163       if (err)
 164         {
 165           grub_printf_ (N_("%s: READ ERROR\n"), p);
 166           if (!keep)
 167             {
 168               grub_file_close (hashlist);
 169               grub_free (buf);
 170               return err;
 171             }
 172           grub_print_error ();
 173           grub_errno = GRUB_ERR_NONE;
 174           unread++;
 175           continue;
 176         }
 177       if (grub_crypto_memcmp (expected, actual, hash->mdlen) != 0)
 178         {
 179           grub_printf_ (N_("%s: HASH MISMATCH\n"), p);
 180           if (!keep)
 181             {
 182               grub_file_close (hashlist);
 183               grub_free (buf);
 184               return grub_error (GRUB_ERR_TEST_FAILURE,
 185                                  "hash of '%s' mismatches", p);
 186             }
 187           mismatch++;
 188           continue;
 189         }
 190       grub_printf_ (N_("%s: OK\n"), p);
 191     }
 192   if (mismatch || unread)
 193     return grub_error (GRUB_ERR_TEST_FAILURE,
 194                        "%d files couldn't be read and hash "
 195                        "of %d files mismatches", unread, mismatch);
 196   return GRUB_ERR_NONE;
 197 }
 198
 199 static grub_err_t
 200 grub_cmd_hashsum (struct grub_extcmd_context *ctxt,
 201                   int argc, char **args)
 202 {
 203   struct grub_arg_list *state = ctxt->state;
 204   const char *hashname = NULL;
 205   const char *prefix = NULL;
 206   const gcry_md_spec_t *hash;
 207   unsigned i;
 208   int keep = state[3].set;
 209   int uncompress = state[4].set;
 210   unsigned unread = 0;
 211
 212   for (i = 0; i < ARRAY_SIZE (aliases); i++)
 213     if (grub_strcmp (ctxt->extcmd->cmd->name, aliases[i].name) == 0)
 214       hashname = aliases[i].hashname;
 215   if (state[0].set)
 216     hashname = state[0].arg;
 217
 218   if (!hashname)
 219     return grub_error (GRUB_ERR_BAD_ARGUMENT, "no hash specified");
 220
 221   hash = grub_crypto_lookup_md_by_name (hashname);
 222   if (!hash)
 223     return grub_error (GRUB_ERR_BAD_ARGUMENT, "unknown hash");
 224
 225   if (hash->mdlen > GRUB_CRYPTO_MAX_MDLEN)
 226     return grub_error (GRUB_ERR_BUG, "mdlen is too long");
 227
 228   if (state[2].set)
 229     prefix = state[2].arg;
 230
 231   if (state[1].set)
 232     {
 233       if (argc != 0)
 234         return grub_error (GRUB_ERR_BAD_ARGUMENT,
 235                            "--check is incompatible with file list");
 236       return check_list (hash, state[1].arg, prefix, keep, uncompress);
 237     }
 238
 239   for (i = 0; i < (unsigned) argc; i++)
 240     {
 241       GRUB_PROPERLY_ALIGNED_ARRAY (result, GRUB_CRYPTO_MAX_MDLEN);
 242       grub_file_t file;
 243       grub_err_t err;
 244       unsigned j;
 245       if (!uncompress)
 246         grub_file_filter_disable_compression ();
 247       file = grub_file_open (args[i]);
 248       if (!file)
 249         {
 250           if (!keep)
 251             return grub_errno;
 252           grub_print_error ();
 253           grub_errno = GRUB_ERR_NONE;
 254           unread++;
 255           continue;
 256         }
 257       err = hash_file (file, hash, result);
 258       grub_file_close (file);
 259       if (err)
 260         {
 261           if (!keep)
 262             return err;
 263           grub_print_error ();
 264           grub_errno = GRUB_ERR_NONE;
 265           unread++;
 266           continue;
 267         }
 268       for (j = 0; j < hash->mdlen; j++)
 269         grub_printf ("%02x", ((grub_uint8_t *) result)[j]);
 270       grub_printf ("  %s\n", args[i]);
 271     }
 272
 273   if (unread)
 274     return grub_error (GRUB_ERR_TEST_FAILURE, "%d files couldn't be read",
 275                        unread);
 276   return GRUB_ERR_NONE;
 277 }
 278
 279 static grub_extcmd_t cmd, cmd_md5, cmd_sha1, cmd_sha256, cmd_sha512, cmd_crc;
 280
 281 GRUB_MOD_INIT(hashsum)
 282 {
 283   cmd = grub_register_extcmd ("hashsum", grub_cmd_hashsum, 0,
 284                               N_("-h HASH [-c FILE [-p PREFIX]] "
 285                                  "[FILE1 [FILE2 ...]]"),
 286                               /* TRANSLATORS: "hash checksum" is just to
 287                                  be a bit more precise, you can treat it as
 288                                  just "hash".  */
 289                               N_("Compute or check hash checksum."),
 290                               options);
 291   cmd_md5 = grub_register_extcmd ("md5sum", grub_cmd_hashsum, 0,
 292                                   N_("[-c FILE [-p PREFIX]] "
 293                                      "[FILE1 [FILE2 ...]]"),
 294                                   N_("Compute or check hash checksum."),
 295                                   options);
 296   cmd_sha1 = grub_register_extcmd ("sha1sum", grub_cmd_hashsum, 0,
 297                                    N_("[-c FILE [-p PREFIX]] "
 298                                       "[FILE1 [FILE2 ...]]"),
 299                                    N_("Compute or check hash checksum."),
 300                                    options);
 301   cmd_sha256 = grub_register_extcmd ("sha256sum", grub_cmd_hashsum, 0,
 302                                      N_("[-c FILE [-p PREFIX]] "
 303                                         "[FILE1 [FILE2 ...]]"),
 304                                      N_("Compute or check hash checksum."),
 305                                      options);
 306   cmd_sha512 = grub_register_extcmd ("sha512sum", grub_cmd_hashsum, 0,
 307                                      N_("[-c FILE [-p PREFIX]] "
 308                                         "[FILE1 [FILE2 ...]]"),
 309                                      N_("Compute or check hash checksum."),
 310                                      options);
 311
 312   cmd_crc = grub_register_extcmd ("crc", grub_cmd_hashsum, 0,
 313                                      N_("[-c FILE [-p PREFIX]] "
 314                                         "[FILE1 [FILE2 ...]]"),
 315                                      N_("Compute or check hash checksum."),
 316                                      options);
 317 }
 318
 319 GRUB_MOD_FINI(hashsum)
 320 {
 321   grub_unregister_extcmd (cmd);
 322   grub_unregister_extcmd (cmd_md5);
 323   grub_unregister_extcmd (cmd_sha1);
 324   grub_unregister_extcmd (cmd_sha256);
 325   grub_unregister_extcmd (cmd_sha512);
 326   grub_unregister_extcmd (cmd_crc);
 327 }