common/hash.c

   1 /*
   2  * Copyright (c) 2012 The Chromium OS Authors.
   3  *
   4  * (C) Copyright 2011
   5  * Joe Hershberger, National Instruments, joe.hershberger@ni.com
   6  *
   7  * (C) Copyright 2000
   8  * Wolfgang Denk, DENX Software Engineering, wd@denx.de.
   9  *
  10  * SPDX-License-Identifier:     GPL-2.0+
  11  */
  12
  13 #ifndef USE_HOSTCC
  14 #include <common.h>
  15 #include <command.h>
  16 #include <malloc.h>
  17 #include <hw_sha.h>
  18 #include <asm/io.h>
  19 #include <asm/errno.h>
  20 #else
  21 #include "mkimage.h"
  22 #include <time.h>
  23 #include <image.h>
  24 #endif /* !USE_HOSTCC*/
  25
  26 #include <hash.h>
  27 #include <u-boot/crc.h>
  28 #include <u-boot/sha1.h>
  29 #include <u-boot/sha256.h>
  30 #include <u-boot/md5.h>
  31
  32 #ifdef CONFIG_SHA1
  33 static int hash_init_sha1(struct hash_algo *algo, void **ctxp)
  34 {
  35         sha1_context *ctx = malloc(sizeof(sha1_context));
  36         sha1_starts(ctx);
  37         *ctxp = ctx;
  38         return 0;
  39 }
  40
  41 static int hash_update_sha1(struct hash_algo *algo, void *ctx, const void *buf,
  42                             unsigned int size, int is_last)
  43 {
  44         sha1_update((sha1_context *)ctx, buf, size);
  45         return 0;
  46 }
  47
  48 static int hash_finish_sha1(struct hash_algo *algo, void *ctx, void *dest_buf,
  49                             int size)
  50 {
  51         if (size < algo->digest_size)
  52                 return -1;
  53
  54         sha1_finish((sha1_context *)ctx, dest_buf);
  55         free(ctx);
  56         return 0;
  57 }
  58 #endif
  59
  60 #ifdef CONFIG_SHA256
  61 static int hash_init_sha256(struct hash_algo *algo, void **ctxp)
  62 {
  63         sha256_context *ctx = malloc(sizeof(sha256_context));
  64         sha256_starts(ctx);
  65         *ctxp = ctx;
  66         return 0;
  67 }
  68
  69 static int hash_update_sha256(struct hash_algo *algo, void *ctx,
  70                               const void *buf, unsigned int size, int is_last)
  71 {
  72         sha256_update((sha256_context *)ctx, buf, size);
  73         return 0;
  74 }
  75
  76 static int hash_finish_sha256(struct hash_algo *algo, void *ctx, void
  77                               *dest_buf, int size)
  78 {
  79         if (size < algo->digest_size)
  80                 return -1;
  81
  82         sha256_finish((sha256_context *)ctx, dest_buf);
  83         free(ctx);
  84         return 0;
  85 }
  86 #endif
  87
  88 static int hash_init_crc32(struct hash_algo *algo, void **ctxp)
  89 {
  90         uint32_t *ctx = malloc(sizeof(uint32_t));
  91         *ctx = 0;
  92         *ctxp = ctx;
  93         return 0;
  94 }
  95
  96 static int hash_update_crc32(struct hash_algo *algo, void *ctx,
  97                              const void *buf, unsigned int size, int is_last)
  98 {
  99         *((uint32_t *)ctx) = crc32(*((uint32_t *)ctx), buf, size);
 100         return 0;
 101 }
 102
 103 static int hash_finish_crc32(struct hash_algo *algo, void *ctx, void *dest_buf,
 104                              int size)
 105 {
 106         if (size < algo->digest_size)
 107                 return -1;
 108
 109         *((uint32_t *)dest_buf) = *((uint32_t *)ctx);
 110         free(ctx);
 111         return 0;
 112 }
 113
 114 /*
 115  * These are the hash algorithms we support. Chips which support accelerated
 116  * crypto could perhaps add named version of these algorithms here. Note that
 117  * algorithm names must be in lower case.
 118  */
 119 static struct hash_algo hash_algo[] = {
 120         /*
 121          * CONFIG_SHA_HW_ACCEL is defined if hardware acceleration is
 122          * available.
 123          */
 124 #ifdef CONFIG_SHA_HW_ACCEL
 125         {
 126                 "sha1",
 127                 SHA1_SUM_LEN,
 128                 hw_sha1,
 129                 CHUNKSZ_SHA1,
 130         }, {
 131                 "sha256",
 132                 SHA256_SUM_LEN,
 133                 hw_sha256,
 134                 CHUNKSZ_SHA256,
 135         },
 136 #endif
 137 #ifdef CONFIG_SHA1
 138         {
 139                 "sha1",
 140                 SHA1_SUM_LEN,
 141                 sha1_csum_wd,
 142                 CHUNKSZ_SHA1,
 143                 hash_init_sha1,
 144                 hash_update_sha1,
 145                 hash_finish_sha1,
 146         },
 147 #endif
 148 #ifdef CONFIG_SHA256
 149         {
 150                 "sha256",
 151                 SHA256_SUM_LEN,
 152                 sha256_csum_wd,
 153                 CHUNKSZ_SHA256,
 154                 hash_init_sha256,
 155                 hash_update_sha256,
 156                 hash_finish_sha256,
 157         },
 158 #endif
 159         {
 160                 "crc32",
 161                 4,
 162                 crc32_wd_buf,
 163                 CHUNKSZ_CRC32,
 164                 hash_init_crc32,
 165                 hash_update_crc32,
 166                 hash_finish_crc32,
 167         },
 168 };
 169
 170 #if defined(CONFIG_SHA256) || defined(CONFIG_CMD_SHA1SUM)
 171 #define MULTI_HASH
 172 #endif
 173
 174 #if defined(CONFIG_HASH_VERIFY) || defined(CONFIG_CMD_HASH)
 175 #define MULTI_HASH
 176 #endif
 177
 178 /* Try to minimize code size for boards that don't want much hashing */
 179 #ifdef MULTI_HASH
 180 #define multi_hash()    1
 181 #else
 182 #define multi_hash()    0
 183 #endif
 184
 185 int hash_lookup_algo(const char *algo_name, struct hash_algo **algop)
 186 {
 187         int i;
 188
 189         for (i = 0; i < ARRAY_SIZE(hash_algo); i++) {
 190                 if (!strcmp(algo_name, hash_algo[i].name)) {
 191                         *algop = &hash_algo[i];
 192                         return 0;
 193                 }
 194         }
 195
 196         debug("Unknown hash algorithm '%s'\n", algo_name);
 197         return -EPROTONOSUPPORT;
 198 }
 199
 200 int hash_progressive_lookup_algo(const char *algo_name,
 201                                  struct hash_algo **algop)
 202 {
 203         int i;
 204
 205         for (i = 0; i < ARRAY_SIZE(hash_algo); i++) {
 206                 if (!strcmp(algo_name, hash_algo[i].name)) {
 207                         if (hash_algo[i].hash_init) {
 208                                 *algop = &hash_algo[i];
 209                                 return 0;
 210                         }
 211                 }
 212         }
 213
 214         debug("Unknown hash algorithm '%s'\n", algo_name);
 215         return -EPROTONOSUPPORT;
 216 }
 217
 218 #ifndef USE_HOSTCC
 219 /**
 220  * store_result: Store the resulting sum to an address or variable
 221  *
 222  * @algo:               Hash algorithm being used
 223  * @sum:                Hash digest (algo->digest_size bytes)
 224  * @dest:               Destination, interpreted as a hex address if it starts
 225  *                      with * (or allow_env_vars is 0) or otherwise as an
 226  *                      environment variable.
 227  * @allow_env_vars:     non-zero to permit storing the result to an
 228  *                      variable environment
 229  */
 230 static void store_result(struct hash_algo *algo, const uint8_t *sum,
 231                          const char *dest, int allow_env_vars)
 232 {
 233         unsigned int i;
 234         int env_var = 0;
 235
 236         /*
 237          * If environment variables are allowed, then we assume that 'dest'
 238          * is an environment variable, unless it starts with *, in which
 239          * case we assume it is an address. If not allowed, it is always an
 240          * address. This is to support the crc32 command.
 241          */
 242         if (allow_env_vars) {
 243                 if (*dest == '*')
 244                         dest++;
 245                 else
 246                         env_var = 1;
 247         }
 248
 249         if (env_var) {
 250                 char str_output[HASH_MAX_DIGEST_SIZE * 2 + 1];
 251                 char *str_ptr = str_output;
 252
 253                 for (i = 0; i < algo->digest_size; i++) {
 254                         sprintf(str_ptr, "%02x", sum[i]);
 255                         str_ptr += 2;
 256                 }
 257                 *str_ptr = '\0';
 258                 setenv(dest, str_output);
 259         } else {
 260                 ulong addr;
 261                 void *buf;
 262
 263                 addr = simple_strtoul(dest, NULL, 16);
 264                 buf = map_sysmem(addr, algo->digest_size);
 265                 memcpy(buf, sum, algo->digest_size);
 266                 unmap_sysmem(buf);
 267         }
 268 }
 269
 270 /**
 271  * parse_verify_sum: Parse a hash verification parameter
 272  *
 273  * @algo:               Hash algorithm being used
 274  * @verify_str:         Argument to parse. If it starts with * then it is
 275  *                      interpreted as a hex address containing the hash.
 276  *                      If the length is exactly the right number of hex digits
 277  *                      for the digest size, then we assume it is a hex digest.
 278  *                      Otherwise we assume it is an environment variable, and
 279  *                      look up its value (it must contain a hex digest).
 280  * @vsum:               Returns binary digest value (algo->digest_size bytes)
 281  * @allow_env_vars:     non-zero to permit storing the result to an environment
 282  *                      variable. If 0 then verify_str is assumed to be an
 283  *                      address, and the * prefix is not expected.
 284  * @return 0 if ok, non-zero on error
 285  */
 286 static int parse_verify_sum(struct hash_algo *algo, char *verify_str,
 287                             uint8_t *vsum, int allow_env_vars)
 288 {
 289         int env_var = 0;
 290
 291         /* See comment above in store_result() */
 292         if (allow_env_vars) {
 293                 if (*verify_str == '*')
 294                         verify_str++;
 295                 else
 296                         env_var = 1;
 297         }
 298
 299         if (!env_var) {
 300                 ulong addr;
 301                 void *buf;
 302
 303                 addr = simple_strtoul(verify_str, NULL, 16);
 304                 buf = map_sysmem(addr, algo->digest_size);
 305                 memcpy(vsum, buf, algo->digest_size);
 306         } else {
 307                 unsigned int i;
 308                 char *vsum_str;
 309                 int digits = algo->digest_size * 2;
 310
 311                 /*
 312                  * As with the original code from sha1sum.c, we assume that a
 313                  * string which matches the digest size exactly is a hex
 314                  * string and not an environment variable.
 315                  */
 316                 if (strlen(verify_str) == digits)
 317                         vsum_str = verify_str;
 318                 else {
 319                         vsum_str = getenv(verify_str);
 320                         if (vsum_str == NULL || strlen(vsum_str) != digits) {
 321                                 printf("Expected %d hex digits in env var\n",
 322                                        digits);
 323                                 return 1;
 324                         }
 325                 }
 326
 327                 for (i = 0; i < algo->digest_size; i++) {
 328                         char *nullp = vsum_str + (i + 1) * 2;
 329                         char end = *nullp;
 330
 331                         *nullp = '\0';
 332                         vsum[i] = simple_strtoul(vsum_str + (i * 2), NULL, 16);
 333                         *nullp = end;
 334                 }
 335         }
 336         return 0;
 337 }
 338
 339 void hash_show(struct hash_algo *algo, ulong addr, ulong len, uint8_t *output)
 340 {
 341         int i;
 342
 343         printf("%s for %08lx ... %08lx ==> ", algo->name, addr, addr + len - 1);
 344         for (i = 0; i < algo->digest_size; i++)
 345                 printf("%02x", output[i]);
 346 }
 347
 348 int hash_block(const char *algo_name, const void *data, unsigned int len,
 349                uint8_t *output, int *output_size)
 350 {
 351         struct hash_algo *algo;
 352         int ret;
 353
 354         ret = hash_lookup_algo(algo_name, &algo);
 355         if (ret)
 356                 return ret;
 357
 358         if (output_size && *output_size < algo->digest_size) {
 359                 debug("Output buffer size %d too small (need %d bytes)",
 360                       *output_size, algo->digest_size);
 361                 return -ENOSPC;
 362         }
 363         if (output_size)
 364                 *output_size = algo->digest_size;
 365         algo->hash_func_ws(data, len, output, algo->chunk_size);
 366
 367         return 0;
 368 }
 369
 370 int hash_command(const char *algo_name, int flags, cmd_tbl_t *cmdtp, int flag,
 371                  int argc, char * const argv[])
 372 {
 373         ulong addr, len;
 374
 375         if ((argc < 2) || ((flags & HASH_FLAG_VERIFY) && (argc < 3)))
 376                 return CMD_RET_USAGE;
 377
 378         addr = simple_strtoul(*argv++, NULL, 16);
 379         len = simple_strtoul(*argv++, NULL, 16);
 380
 381         if (multi_hash()) {
 382                 struct hash_algo *algo;
 383                 uint8_t output[HASH_MAX_DIGEST_SIZE];
 384                 uint8_t vsum[HASH_MAX_DIGEST_SIZE];
 385                 void *buf;
 386
 387                 if (hash_lookup_algo(algo_name, &algo)) {
 388                         printf("Unknown hash algorithm '%s'\n", algo_name);
 389                         return CMD_RET_USAGE;
 390                 }
 391                 argc -= 2;
 392
 393                 if (algo->digest_size > HASH_MAX_DIGEST_SIZE) {
 394                         puts("HASH_MAX_DIGEST_SIZE exceeded\n");
 395                         return 1;
 396                 }
 397
 398                 buf = map_sysmem(addr, len);
 399                 algo->hash_func_ws(buf, len, output, algo->chunk_size);
 400                 unmap_sysmem(buf);
 401
 402                 /* Try to avoid code bloat when verify is not needed */
 403 #ifdef CONFIG_HASH_VERIFY
 404                 if (flags & HASH_FLAG_VERIFY) {
 405 #else
 406                 if (0) {
 407 #endif
 408                         if (parse_verify_sum(algo, *argv, vsum,
 409                                         flags & HASH_FLAG_ENV)) {
 410                                 printf("ERROR: %s does not contain a valid "
 411                                         "%s sum\n", *argv, algo->name);
 412                                 return 1;
 413                         }
 414                         if (memcmp(output, vsum, algo->digest_size) != 0) {
 415                                 int i;
 416
 417                                 hash_show(algo, addr, len, output);
 418                                 printf(" != ");
 419                                 for (i = 0; i < algo->digest_size; i++)
 420                                         printf("%02x", vsum[i]);
 421                                 puts(" ** ERROR **\n");
 422                                 return 1;
 423                         }
 424                 } else {
 425                         hash_show(algo, addr, len, output);
 426                         printf("\n");
 427
 428                         if (argc) {
 429                                 store_result(algo, output, *argv,
 430                                         flags & HASH_FLAG_ENV);
 431                         }
 432                 }
 433
 434         /* Horrible code size hack for boards that just want crc32 */
 435         } else {
 436                 ulong crc;
 437                 ulong *ptr;
 438
 439                 crc = crc32_wd(0, (const uchar *)addr, len, CHUNKSZ_CRC32);
 440
 441                 printf("CRC32 for %08lx ... %08lx ==> %08lx\n",
 442                                 addr, addr + len - 1, crc);
 443
 444                 if (argc >= 3) {
 445                         ptr = (ulong *)simple_strtoul(argv[0], NULL, 16);
 446                         *ptr = crc;
 447                 }
 448         }
 449
 450         return 0;
 451 }
 452 #endif