rockbox/utils/samsungtools/fwdecrypt.c
Amaury Pouly d66c16749a Introduce samsungtools to decrypt samsung firmware
Samsung provides many firmware upgrade in the format of a .dat
file, at least for nearly all YP's (checked for Q2, R0, T10, Z5).
This is a simple cyclic xor which a fixed key, a md5 sum and a
header specifying the model/version/region.

Change-Id: Ib0461a74196383189fd2d8162da444a85a229c60
2012-11-29 17:30:54 +01:00

131 lines
3.3 KiB
C

/***************************************************************************
* __________ __ ___.
* Open \______ \ ____ ____ | | _\_ |__ _______ ___
* Source | _// _ \_/ ___\| |/ /| __ \ / _ \ \/ /
* Jukebox | | ( <_> ) \___| < | \_\ ( <_> > < <
* Firmware |____|_ /\____/ \___ >__|_ \|___ /\____/__/\_ \
* \/ \/ \/ \/ \/
* $Id$
*
* Copyright (C) 2012 Amaury Pouly
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License
* as published by the Free Software Foundation; either version 2
* of the License, or (at your option) any later version.
*
* This software is distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY
* KIND, either express or implied.
*
****************************************************************************/
#include "samsung.h"
#include <stdio.h>
#include <stdlib.h>
#include <stdarg.h>
#include <getopt.h>
static bool g_debug = false;
static char *g_out_prefix = NULL;
static void usage(void)
{
printf("Usage: fwdecrypt [options] firmware\n");
printf("Options:\n");
printf(" -o <prefix>\tSet output file\n");
printf(" -f/--force\tForce to continue on errors\n");
printf(" -?/--help\tDisplay this message\n");
printf(" -d/--debug\tDisplay debug messages\n");
exit(1);
}
static int s_read(void *user, int offset, void *buf, int size)
{
FILE *f = user;
if(fseek(f, offset, SEEK_SET) != 0)
return 0;
return fread(buf, 1, size, f);
}
static void s_printf(void *user, bool error, const char *fmt, ...)
{
if(!g_debug && !error)
return;
(void) user;
va_list args;
va_start(args, fmt);
vprintf(fmt, args);
va_end(args);
}
int main(int argc, char **argv)
{
if(argc <= 1)
usage();
while(1)
{
static struct option long_options[] =
{
{"help", no_argument, 0, '?'},
{"debug", no_argument, 0, 'd'},
{0, 0, 0, 0}
};
int c = getopt_long(argc, argv, "?do:", long_options, NULL);
if(c == -1)
break;
switch(c)
{
case -1:
break;
case 'd':
g_debug = true;
break;
case '?':
usage();
break;
case 'o':
g_out_prefix = optarg;
break;
default:
abort();
}
}
if(optind != argc - 1)
usage();
FILE *f = fopen(argv[optind], "rb");
if(f == NULL)
{
printf("Cannot open file for reading: %m\n");
return 1;
}
enum samsung_error_t err;
struct samsung_firmware_t *fw = samsung_read(s_read, s_printf,
f, &err);
if(fw == NULL || err != SAMSUNG_SUCCESS)
{
printf("Error reading firmware: %d\n", err);
samsung_free(fw);
return 1;
}
fclose(f);
if(g_out_prefix)
{
f = fopen(g_out_prefix, "wb");
if(f == NULL)
{
printf("Cannot open file for writing: %m\n");
return 2;
}
fwrite(fw->data, 1, fw->data_size, f);
fclose(f);
}
samsung_free(fw);
return 0;
}