rbutil/mkimxboot/mkimxboot.c

   1 /***************************************************************************
   2  *             __________               __   ___.
   3  *   Open      \______   \ ____   ____ |  | _\_ |__   _______  ___
   4  *   Source     |       _//  _ \_/ ___\|  |/ /| __ \ /  _ \  \/  /
   5  *   Jukebox    |    |   (  <_> )  \___|    < | \_\ (  <_> > <  <
   6  *   Firmware   |____|_  /\____/ \___  >__|_ \|___  /\____/__/\_ \
   7  *                     \/            \/     \/    \/            \/
   8  * $Id$
   9  *
  10  * Copyright (C) 2011 by Amaury Pouly
  11  *
  12  * This program is free software; you can redistribute it and/or
  13  * modify it under the terms of the GNU General Public License
  14  * as published by the Free Software Foundation; either version 2
  15  * of the License, or (at your option) any later version.
  16  *
  17  * This software is distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY
  18  * KIND, either express or implied.
  19  *
  20  ****************************************************************************/
  21 #include <stdio.h>
  22 #include <stdlib.h>
  23 #include <stdarg.h>
  24 #include "mkimxboot.h"
  25 #include "sb.h"
  26 #include "dualboot.h"
  27 #include "md5.h"
  28
  29 struct imx_fw_variant_desc_t
  30 {
  31     /* Offset within file */
  32     size_t offset;
  33     /* Total size of the firmware */
  34     size_t size;
  35 };
  36
  37 struct imx_md5sum_t
  38 {
  39     /* Device model */
  40     enum imx_model_t model;
  41     /* md5sum of the file */
  42     char *md5sum;
  43     /* Version string */
  44     const char *version;
  45     /* Variant descriptions */
  46     struct imx_fw_variant_desc_t fw_variants[VARIANT_COUNT];
  47 };
  48
  49 struct imx_model_desc_t
  50 {
  51     /* Descriptive name of this model */
  52     const char *model_name;
  53     /* Dualboot code for this model */
  54     const unsigned char *dualboot;
  55     /* Size of dualboot functions for this model */
  56     int dualboot_size;
  57     /* Model name used in the Rockbox header in ".sansa" files - these match the
  58        -add parameter to the "scramble" tool */
  59     const char *rb_model_name;
  60     /* Model number used to initialise the checksum in the Rockbox header in
  61        ".sansa" files - these are the same as MODEL_NUMBER in config-target.h */
  62     const int rb_model_num;
  63     /* Number of keys needed to decrypt/encrypt */
  64     int nr_keys;
  65     /* Array of keys */
  66     struct crypto_key_t *keys;
  67     /* Dualboot load address */
  68     uint32_t dualboot_addr;
  69     /* Bootloader load address */
  70     uint32_t bootloader_addr;
  71 };
  72
  73 static const char *imx_fw_variant[] =
  74 {
  75     [VARIANT_DEFAULT] = "default",
  76     [VARIANT_ZENXFI2_RECOVERY] = "ZEN X-Fi2 Recovery",
  77     [VARIANT_ZENXFI2_NAND] = "ZEN X-Fi2 NAND",
  78     [VARIANT_ZENXFI2_SD] = "ZEN X-Fi2 eMMC/SD",
  79 };
  80
  81 static const struct imx_md5sum_t imx_sums[] =
  82 {
  83     {
  84         /* Version 2.38.6 */
  85         MODEL_FUZEPLUS, "c3e27620a877dc6b200b97dcb3e0ecc7", "2.38.6",
  86         { [VARIANT_DEFAULT] = { 0, 34652624 } }
  87     },
  88     {
  89         /* Version 1.23.01e */
  90         MODEL_ZENXFI2, "e37e2c24abdff8e624d0a29f79157850", "1.23.01e",
  91     },
  92     {
  93         /* Version 1.23.01e */
  94         MODEL_ZENXFI2, "2beff2168212d332f13cfc36ca46989d", "1.23.01e",
  95         { [VARIANT_ZENXFI2_RECOVERY] = { 0x93010, 684192},
  96           [VARIANT_ZENXFI2_NAND] = { 0x13a0b0, 42410704 },
  97           [VARIANT_ZENXFI2_SD] = { 0x29ac380, 42304208 }
  98         }
  99     },
 100     {
 101         /* Version 1.00.15e */
 102         MODEL_ZENXFI3, "658a24eeef5f7186ca731085d8822a87", "1.00.15e",
 103         { [VARIANT_DEFAULT] = {0, 18110576} }
 104     },
 105     {
 106         /* Version 1.00.22e */
 107         MODEL_ZENXFI3, "a5114cd45ea4554ec221f51a71083862", "1.00.22e",
 108         { [VARIANT_DEFAULT] = {0, 18110576} }
 109     },
 110 };
 111
 112 static struct crypto_key_t zero_key =
 113 {
 114     .method = CRYPTO_KEY,
 115     .u.key = {0}
 116 };
 117
 118 static const struct imx_model_desc_t imx_models[] =
 119 {
 120     [MODEL_FUZEPLUS] = { "Fuze+",  dualboot_fuzeplus, sizeof(dualboot_fuzeplus), "fuz+", 72,
 121                           1, &zero_key, 0, 0x40000000 },
 122     [MODEL_ZENXFI2] = {"Zen X-Fi2", dualboot_zenxfi2, sizeof(dualboot_zenxfi2), "zxf2", 82,
 123                        1, &zero_key, 0, 0x40000000 },
 124     [MODEL_ZENXFI3] = {"Zen X-Fi3", dualboot_zenxfi3, sizeof(dualboot_zenxfi3), "zxf3", 83,
 125                        1, &zero_key, 0, 0x40000000 },
 126 };
 127
 128 #define NR_IMX_SUMS     (sizeof(imx_sums) / sizeof(imx_sums[0]))
 129 #define NR_IMX_MODELS   (sizeof(imx_models) / sizeof(imx_models[0]))
 130
 131 #define MAGIC_ROCK      0x726f636b /* 'rock' */
 132 #define MAGIC_RECOVERY  0xfee1dead
 133 #define MAGIC_NORMAL    0xcafebabe
 134
 135 static enum imx_error_t patch_std_zero_host_play(int jump_before, int model,
 136  enum imx_output_type_t type, struct sb_file_t *sb_file, void *boot, size_t boot_sz)
 137 {
 138     /* We assume the file has three boot sections: ____, host, play and one
 139      * resource section rsrc.
 140      *
 141      * Dual Boot:
 142      * ----------
 143      * We patch the file by inserting the dualboot code before the <jump_before>th
 144      * call in the ____ section. We give it as argument the section name 'rock'
 145      * and add a section called 'rock' after rsrc which contains the bootloader.
 146      *
 147      * Single Boot & Recovery:
 148      * -----------------------
 149      * We patch the file by inserting the bootloader code after the <jump_before>th
 150      * call in the ____ section and get rid of everything else. In recovery mode,
 151      * we give 0xfee1dead as argument */
 152
 153     /* Do not override real key and IV */
 154     sb_file->override_crypto_iv = false;
 155     sb_file->override_real_key = false;
 156
 157     /* first locate the good instruction */
 158     struct sb_section_t *sec = &sb_file->sections[0];
 159     int jump_idx = 0;
 160     while(jump_idx < sec->nr_insts && jump_before > 0)
 161         if(sec->insts[jump_idx++].inst == SB_INST_CALL)
 162             jump_before--;
 163     if(jump_idx == sec->nr_insts)
 164     {
 165         printf("[ERR] Cannot locate call in section ____\n");
 166         return IMX_DONT_KNOW_HOW_TO_PATCH;
 167     }
 168
 169     if(type == IMX_DUALBOOT)
 170     {
 171         /* create a new instruction array with a hole for two instructions */
 172         struct sb_inst_t *new_insts = xmalloc(sizeof(struct sb_inst_t) * (sec->nr_insts + 2));
 173         memcpy(new_insts, sec->insts, sizeof(struct sb_inst_t) * jump_idx);
 174         memcpy(new_insts + jump_idx + 2, sec->insts + jump_idx,
 175             sizeof(struct sb_inst_t) * (sec->nr_insts - jump_idx));
 176         /* first instruction is be a load */
 177         struct sb_inst_t *load = &new_insts[jump_idx];
 178         memset(load, 0, sizeof(struct sb_inst_t));
 179         load->inst = SB_INST_LOAD;
 180         load->size = imx_models[model].dualboot_size;
 181         load->addr = imx_models[model].dualboot_addr;
 182         /* duplicate memory because it will be free'd */
 183         load->data = memdup(imx_models[model].dualboot, imx_models[model].dualboot_size);
 184         /* second instruction is a call */
 185         struct sb_inst_t *call = &new_insts[jump_idx + 1];
 186         memset(call, 0, sizeof(struct sb_inst_t));
 187         call->inst = SB_INST_CALL;
 188         call->addr = imx_models[model].dualboot_addr;
 189         call->argument = MAGIC_ROCK;
 190         /* free old instruction array */
 191         free(sec->insts);
 192         sec->insts = new_insts;
 193         sec->nr_insts += 2;
 194
 195         /* create a new section */
 196         struct sb_section_t rock_sec;
 197         memset(&rock_sec, 0, sizeof(rock_sec));
 198         /* section has two instructions: load and call */
 199         rock_sec.identifier = MAGIC_ROCK;
 200         rock_sec.alignment = BLOCK_SIZE;
 201         rock_sec.nr_insts = 2;
 202         rock_sec.insts = xmalloc(2 * sizeof(struct sb_inst_t));
 203         memset(rock_sec.insts, 0, 2 * sizeof(struct sb_inst_t));
 204         rock_sec.insts[0].inst = SB_INST_LOAD;
 205         rock_sec.insts[0].size = boot_sz;
 206         rock_sec.insts[0].data = memdup(boot, boot_sz);
 207         rock_sec.insts[0].addr = imx_models[model].bootloader_addr;
 208         rock_sec.insts[1].inst = SB_INST_JUMP;
 209         rock_sec.insts[1].addr = imx_models[model].bootloader_addr;
 210         rock_sec.insts[1].argument = MAGIC_NORMAL;
 211
 212         sb_file->sections = augment_array(sb_file->sections,
 213             sizeof(struct sb_section_t), sb_file->nr_sections,
 214             &rock_sec, 1);
 215         sb_file->nr_sections++;
 216
 217         return IMX_SUCCESS;
 218     }
 219     else if(type == IMX_SINGLEBOOT || type == IMX_RECOVERY)
 220     {
 221         bool recovery = type == IMX_RECOVERY;
 222         /* remove everything after the call and add two instructions: load and call */
 223         struct sb_inst_t *new_insts = xmalloc(sizeof(struct sb_inst_t) * (jump_idx + 2));
 224         memcpy(new_insts, sec->insts, sizeof(struct sb_inst_t) * jump_idx);
 225         for(int i = jump_idx; i < sec->nr_insts; i++)
 226             sb_free_instruction(sec->insts[i]);
 227         memset(new_insts + jump_idx, 0, 2 * sizeof(struct sb_inst_t));
 228         new_insts[jump_idx + 0].inst = SB_INST_LOAD;
 229         new_insts[jump_idx + 0].size = boot_sz;
 230         new_insts[jump_idx + 0].data = memdup(boot, boot_sz);
 231         new_insts[jump_idx + 0].addr = imx_models[model].bootloader_addr;
 232         new_insts[jump_idx + 1].inst = SB_INST_JUMP;
 233         new_insts[jump_idx + 1].addr = imx_models[model].bootloader_addr;
 234         new_insts[jump_idx + 1].argument = recovery ? MAGIC_RECOVERY : MAGIC_NORMAL;
 235
 236         free(sec->insts);
 237         sec->insts = new_insts;
 238         sec->nr_insts = jump_idx + 2;
 239         /* remove all other sections */
 240         for(int i = 1; i < sb_file->nr_sections; i++)
 241             sb_free_section(sb_file->sections[i]);
 242         struct sb_section_t *new_sec = xmalloc(sizeof(struct sb_section_t));
 243         memcpy(new_sec, &sb_file->sections[0], sizeof(struct sb_section_t));
 244         free(sb_file->sections);
 245         sb_file->sections = new_sec;
 246         sb_file->nr_sections = 1;
 247
 248         return IMX_SUCCESS;
 249     }
 250     else
 251     {
 252         printf("[ERR] Bad output type !\n");
 253         return IMX_DONT_KNOW_HOW_TO_PATCH;
 254     }
 255 }
 256
 257 static enum imx_error_t patch_firmware(enum imx_model_t model,
 258     enum imx_firmware_variant_t variant, enum imx_output_type_t type,
 259     struct sb_file_t *sb_file, void *boot, size_t boot_sz)
 260 {
 261     switch(model)
 262     {
 263         case MODEL_FUZEPLUS:
 264             /* The Fuze+ uses the standard ____, host, play sections, patch after third
 265              * call in ____ section */
 266             return patch_std_zero_host_play(3, model, type, sb_file, boot, boot_sz);
 267         case MODEL_ZENXFI3:
 268             /* The ZEN X-Fi3 uses the standard ____, hSst, pSay sections, patch after third
 269              * call in ____ section. Although sections names use the S variant, they are standard. */
 270             return patch_std_zero_host_play(3, model, type, sb_file, boot, boot_sz);
 271         case MODEL_ZENXFI2:
 272             /* The ZEN X-Fi2 has two types of firmware: recovery and normal.
 273              * Normal uses the standard ___, host, play sections and recovery only ____ */
 274             switch(variant)
 275             {
 276                 case VARIANT_ZENXFI2_RECOVERY:
 277                 case VARIANT_ZENXFI2_NAND:
 278                 case VARIANT_ZENXFI2_SD:
 279                     return patch_std_zero_host_play(1, model, type, sb_file, boot, boot_sz);
 280                 default:
 281                     return IMX_DONT_KNOW_HOW_TO_PATCH;
 282             }
 283             break;
 284         default:
 285             return IMX_DONT_KNOW_HOW_TO_PATCH;
 286     }
 287 }
 288
 289 static void imx_printf(void *user, bool error, color_t c, const char *fmt, ...)
 290 {
 291     (void) user;
 292     (void) c;
 293     va_list args;
 294     va_start(args, fmt);
 295     /*
 296     if(error)
 297         printf("[ERR] ");
 298     else
 299         printf("[INFO] ");
 300     */
 301     vprintf(fmt, args);
 302     va_end(args);
 303 }
 304
 305 static uint32_t get_uint32be(unsigned char *p)
 306 {
 307     return (p[0] << 24) | (p[1] << 16) | (p[2] << 8) | p[3];
 308 }
 309
 310 void dump_imx_dev_info(const char *prefix)
 311 {
 312     printf("%smkimxboot models:\n", prefix);
 313     for(int i = 0; i < NR_IMX_MODELS; i++)
 314     {
 315         printf("%s  %s: idx=%d rb_model=%s rb_num=%d\n", prefix,
 316             imx_models[i].model_name, i, imx_models[i].rb_model_name,
 317             imx_models[i].rb_model_num);
 318     }
 319     printf("%smkimxboot variants:\n", prefix);
 320     for(int i = 0; i < VARIANT_COUNT; i++)
 321     {
 322         printf("%s  %d: %s\n", prefix, i, imx_fw_variant[i]);
 323     }
 324     printf("%smkimxboot mapping:\n", prefix);
 325     for(int i = 0; i < NR_IMX_SUMS; i++)
 326     {
 327         printf("%s  md5sum=%s -> idx=%d, ver=%s\n", prefix, imx_sums[i].md5sum,
 328             imx_sums[i].model, imx_sums[i].version);
 329         for(int j = 0; j < VARIANT_COUNT; j++)
 330             if(imx_sums[i].fw_variants[j].size)
 331                 printf("%s    variant=%d -> offset=%#x size=%#x\n", prefix,
 332                     j, (unsigned)imx_sums[i].fw_variants[j].offset,
 333                     (unsigned)imx_sums[i].fw_variants[j].size);
 334     }
 335 }
 336
 337 enum imx_error_t mkimxboot(const char *infile, const char *bootfile,
 338     const char *outfile, struct imx_option_t opt)
 339 {
 340     /* Dump tables */
 341     if(opt.fw_variant > VARIANT_COUNT) {
 342         return IMX_ERROR;
 343     }
 344     dump_imx_dev_info("[INFO] ");
 345     /* compute MD5 sum of the file */
 346     uint8_t file_md5sum[16];
 347     do
 348     {
 349         FILE *f = fopen(infile, "rb");
 350         if(f == NULL)
 351         {
 352             printf("[ERR] Cannot open input file\n");
 353             return IMX_OPEN_ERROR;
 354         }
 355         fseek(f, 0, SEEK_END);
 356         size_t sz = ftell(f);
 357         fseek(f, 0, SEEK_SET);
 358         void *buf = xmalloc(sz);
 359         if(fread(buf, sz, 1, f) != 1)
 360         {
 361             fclose(f);
 362             free(buf);
 363             printf("[ERR] Cannot read file\n");
 364             return IMX_READ_ERROR;
 365         }
 366         fclose(f);
 367         md5_context ctx;
 368         md5_starts(&ctx);
 369         md5_update(&ctx, buf, sz);
 370         md5_finish(&ctx, file_md5sum);
 371         free(buf);
 372     }while(0);
 373     printf("[INFO] MD5 sum of the file: ");
 374     print_hex(file_md5sum, 16, true);
 375     /* find model */
 376     enum imx_model_t model;
 377     int md5_idx;
 378     do
 379     {
 380         int i = 0;
 381         while(i < NR_IMX_SUMS)
 382         {
 383             uint8_t md5[20];
 384             if(strlen(imx_sums[i].md5sum) != 32)
 385             {
 386                 printf("[INFO] Invalid MD5 sum in imx_sums\n");
 387                 return IMX_ERROR;
 388             }
 389             for(int j = 0; j < 16; j++)
 390             {
 391                 byte a, b;
 392                 if(convxdigit(imx_sums[i].md5sum[2 * j], &a) || convxdigit(imx_sums[i].md5sum[2 * j + 1], &b))
 393                 {
 394                     printf("[ERR][INTERNAL] Bad checksum format: %s\n", imx_sums[i].md5sum);
 395                     return IMX_ERROR;
 396                 }
 397                 md5[j] = (a << 4) | b;
 398             }
 399             if(memcmp(file_md5sum, md5, 16) == 0)
 400                 break;
 401             i++;
 402         }
 403         if(i == NR_IMX_SUMS)
 404         {
 405             printf("[ERR] MD5 sum doesn't match any known file\n");
 406             return IMX_NO_MATCH;
 407         }
 408         model = imx_sums[i].model;
 409         md5_idx = i;
 410     }while(0);
 411     printf("[INFO] File is for model %d (%s, version %s)\n", model,
 412         imx_models[model].model_name, imx_sums[md5_idx].version);
 413     /* load rockbox file */
 414     uint8_t *boot;
 415     size_t boot_size;
 416     do
 417     {
 418         FILE *f = fopen(bootfile, "rb");
 419         if(f == NULL)
 420         {
 421             printf("[ERR] Cannot open boot file\n");
 422             return IMX_OPEN_ERROR;
 423         }
 424         fseek(f, 0, SEEK_END);
 425         boot_size = ftell(f);
 426         fseek(f, 0, SEEK_SET);
 427         boot = xmalloc(boot_size);
 428         if(fread(boot, boot_size, 1, f) != 1)
 429         {
 430             free(boot);
 431             fclose(f);
 432             printf("[ERR] Cannot read boot file\n");
 433             return IMX_READ_ERROR;
 434         }
 435         fclose(f);
 436     }while(0);
 437     /* Check boot file */
 438     do
 439     {
 440         if(boot_size < 8)
 441         {
 442             printf("[ERR] Bootloader file is too small to be valid\n");
 443             free(boot);
 444             return IMX_BOOT_INVALID;
 445         }
 446         /* check model name */
 447         uint8_t *name = boot + 4;
 448         if(memcmp(name, imx_models[model].rb_model_name, 4) != 0)
 449         {
 450             printf("[ERR] Bootloader model doesn't match found model for input file\n");
 451             free(boot);
 452             return IMX_BOOT_MISMATCH;
 453         }
 454         /* check checksum */
 455         uint32_t sum = imx_models[model].rb_model_num;
 456         for(int i = 8; i < boot_size; i++)
 457             sum += boot[i];
 458         if(sum != get_uint32be(boot))
 459         {
 460             printf("[ERR] Bootloader checksum mismatch\n");
 461             free(boot);
 462             return IMX_BOOT_CHECKSUM_ERROR;
 463         }
 464     }while(0);
 465     /* load OF file */
 466     struct sb_file_t *sb_file;
 467     do
 468     {
 469         if(imx_sums[md5_idx].fw_variants[opt.fw_variant].size == 0)
 470         {
 471             printf("[ERR] Input file does not contain variant '%s'\n", imx_fw_variant[opt.fw_variant]);
 472             free(boot);
 473             return IMX_VARIANT_MISMATCH;
 474         }
 475         enum sb_error_t err;
 476         g_debug = opt.debug;
 477         clear_keys();
 478         add_keys(imx_models[model].keys, imx_models[model].nr_keys);
 479         sb_file = sb_read_file_ex(infile, imx_sums[md5_idx].fw_variants[opt.fw_variant].offset,
 480             imx_sums[md5_idx].fw_variants[opt.fw_variant].size, false, NULL, &imx_printf, &err);
 481         if(sb_file == NULL)
 482         {
 483             clear_keys();
 484             free(boot);
 485             return IMX_FIRST_SB_ERROR + err;
 486         }
 487     }while(0);
 488     /* produce file */
 489     enum imx_error_t ret = patch_firmware(model, opt.fw_variant, opt.output, sb_file, boot + 8, boot_size - 8);
 490     if(ret == IMX_SUCCESS)
 491         ret = sb_write_file(sb_file, outfile);
 492
 493     clear_keys();
 494     free(boot);
 495     sb_free(sb_file);
 496     return ret;
 497 }
 498
 499 enum imx_error_t extract_firmware(const char *infile,
 500     enum imx_firmware_variant_t fw_variant, const char *outfile)
 501 {
 502     /* Dump tables */
 503     if(fw_variant > VARIANT_COUNT) {
 504         return IMX_ERROR;
 505     }
 506     dump_imx_dev_info("[INFO] ");
 507     /* compute MD5 sum of the file */
 508     uint8_t file_md5sum[16];
 509     FILE *f = fopen(infile, "rb");
 510     if(f == NULL)
 511     {
 512         printf("[ERR] Cannot open input file\n");
 513         return IMX_OPEN_ERROR;
 514     }
 515     fseek(f, 0, SEEK_END);
 516     size_t sz = ftell(f);
 517     fseek(f, 0, SEEK_SET);
 518     void *buf = xmalloc(sz);
 519     if(fread(buf, sz, 1, f) != 1)
 520     {
 521         fclose(f);
 522         free(buf);
 523         printf("[ERR] Cannot read file\n");
 524         return IMX_READ_ERROR;
 525     }
 526     md5_context ctx;
 527     md5_starts(&ctx);
 528     md5_update(&ctx, buf, sz);
 529     md5_finish(&ctx, file_md5sum);
 530     fclose(f);
 531
 532     printf("[INFO] MD5 sum of the file: ");
 533     print_hex(file_md5sum, 16, true);
 534     /* find model */
 535     enum imx_model_t model;
 536     int md5_idx;
 537     do
 538     {
 539         int i = 0;
 540         while(i < NR_IMX_SUMS)
 541         {
 542             uint8_t md5[20];
 543             if(strlen(imx_sums[i].md5sum) != 32)
 544             {
 545                 printf("[INFO] Invalid MD5 sum in imx_sums\n");
 546                 return IMX_ERROR;
 547             }
 548             for(int j = 0; j < 16; j++)
 549             {
 550                 byte a, b;
 551                 if(convxdigit(imx_sums[i].md5sum[2 * j], &a) || convxdigit(imx_sums[i].md5sum[2 * j + 1], &b))
 552                 {
 553                     printf("[ERR][INTERNAL] Bad checksum format: %s\n", imx_sums[i].md5sum);
 554                     free(buf);
 555                     return IMX_ERROR;
 556                 }
 557                 md5[j] = (a << 4) | b;
 558             }
 559             if(memcmp(file_md5sum, md5, 16) == 0)
 560                 break;
 561             i++;
 562         }
 563         if(i == NR_IMX_SUMS)
 564         {
 565             printf("[ERR] MD5 sum doesn't match any known file\n");
 566             return IMX_NO_MATCH;
 567         }
 568         model = imx_sums[i].model;
 569         md5_idx = i;
 570     }while(0);
 571     printf("[INFO] File is for model %d (%s, version %s)\n", model,
 572         imx_models[model].model_name, imx_sums[md5_idx].version);
 573
 574     if(imx_sums[md5_idx].fw_variants[fw_variant].size == 0)
 575     {
 576         printf("[ERR] Input file does not contain variant '%s'\n", imx_fw_variant[fw_variant]);
 577         free(buf);
 578         return IMX_VARIANT_MISMATCH;
 579     }
 580
 581     f = fopen(outfile, "wb");
 582     if(f == NULL)
 583     {
 584         printf("[ERR] Cannot open input file\n");
 585         free(buf);
 586         return IMX_OPEN_ERROR;
 587     }
 588     enum imx_error_t ret = IMX_SUCCESS;
 589
 590     if(fwrite(buf + imx_sums[md5_idx].fw_variants[fw_variant].offset,
 591             imx_sums[md5_idx].fw_variants[fw_variant].size, 1, f) != 1)
 592     {
 593         printf("[ERR] Cannot write file\n");
 594         ret = IMX_ERROR;
 595     }
 596     fclose(f);
 597     free(buf);
 598
 599     return ret;
 600 }