/*************************************************************************** * __________ __ ___. * 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 #include #include #ifndef MIN #define MIN(a,b) ((a) < (b) ? (a) : (b)) #endif static uint8_t g_yp_key[128] = { 0xa3, 0x04, 0xb9, 0xcd, 0x34, 0x13, 0x4a, 0x19, 0x19, 0x35, 0xdf, 0xbb, 0x8f, 0x3d, 0x7f, 0x09, 0x42, 0x3c, 0x96, 0xc6, 0x41, 0xa9, 0x95, 0xf1, 0xd0, 0xac, 0x16, 0x37, 0x57, 0x1f, 0x28, 0xe7, 0x0b, 0xc2, 0x12, 0x09, 0x39, 0x42, 0xd2, 0x96, 0xf5, 0x00, 0xd2, 0x23, 0xa4, 0x24, 0xe2, 0x8e, 0x50, 0x3c, 0x6e, 0x23, 0xeb, 0x68, 0xed, 0x31, 0xb7, 0xee, 0xc0, 0xc7, 0x09, 0xf8, 0x0e, 0x9d, 0x51, 0xed, 0x17, 0x95, 0x64, 0x09, 0xe0, 0xf9, 0xf0, 0xef, 0x86, 0xc0, 0x04, 0x46, 0x89, 0x8a, 0x6e, 0x27, 0x69, 0xde, 0xc7, 0x9d, 0x1e, 0xee, 0x3c, 0x3f, 0x17, 0x05, 0x44, 0xbb, 0xbb, 0x1d, 0x3d, 0x5d, 0x6e, 0xf2, 0xcf, 0x15, 0xd6, 0x3c, 0xcc, 0x7d, 0x67, 0x1a, 0xb8, 0xd2, 0x1b, 0x54, 0x97, 0xa2, 0x58, 0x58, 0xf7, 0x4e, 0x5e, 0x50, 0x42, 0x69, 0xdc, 0xe7, 0x3a, 0x87, 0x2e, 0x22 }; static void cyclic_xor(void *data, int datasize, void *xor, int xorsize) { for(int i = 0; i < datasize; i++) *(uint8_t *)(data + i) ^= *(uint8_t *)(xor + (i % xorsize)); } struct samsung_firmware_t *samsung_read(samsung_read_t read, samsung_printf_t printf, void *user, enum samsung_error_t *err) { struct yp_header_t yp_hdr; struct yp_md5_t yp_md5; /* read and check header */ if(read(user, 0, &yp_hdr, sizeof(yp_hdr)) != sizeof(yp_hdr)) { printf(user, true, "Cannot read YP header\n"); *err = SAMSUNG_READ_ERROR; return NULL; } if(strncmp(yp_hdr.signature, YP_SIGNATURE, sizeof(yp_hdr.signature)) != 0) { printf(user, true, "Bad YP signature\n"); *err = SAMSUNG_FORMAT_ERROR; return NULL; } printf(user, false, "Model: %s\n", yp_hdr.model); printf(user, false, "Version: %s %s %s\n", yp_hdr.version, yp_hdr.region, yp_hdr.extra); /* allocate and read data */ struct samsung_firmware_t *fw = malloc(sizeof(struct samsung_firmware_t)); memset(fw, 0, sizeof(struct samsung_firmware_t)); fw->data_size = yp_hdr.datasize; fw->data = malloc(fw->data_size); strncpy(fw->version, yp_hdr.version, sizeof(yp_hdr.version)); strncpy(fw->region, yp_hdr.region, sizeof(yp_hdr.region)); strncpy(fw->extra, yp_hdr.extra, sizeof(yp_hdr.extra)); strncpy(fw->model, yp_hdr.model, sizeof(yp_hdr.model)); if(read(user, sizeof(yp_hdr), fw->data, fw->data_size) != fw->data_size) { printf(user, true, "Cannot read data\n"); *err = SAMSUNG_READ_ERROR; samsung_free(fw); return NULL; } /* read and check MD5 */ if(read(user, yp_hdr.datasize + sizeof(yp_hdr), &yp_md5, sizeof(yp_md5)) != sizeof(yp_md5)) { printf(user, true, "Cannot read MD5 sum\n"); *err = SAMSUNG_READ_ERROR; samsung_free(fw); return NULL; } uint8_t actual_md5[MD5_DIGEST_LENGTH]; MD5_CTX c; MD5_Init(&c); MD5_Update(&c, fw->data, fw->data_size); MD5_Final(actual_md5, &c); if(memcmp(actual_md5, yp_md5.md5, MD5_DIGEST_LENGTH) != 0) { printf(user, true, "MD5 mismatch\n"); *err = SAMSUNG_MD5_ERROR; samsung_free(fw); return NULL; } /* decrypt */ cyclic_xor(fw->data, fw->data_size, g_yp_key, sizeof(g_yp_key)); /* success ! */ *err = SAMSUNG_SUCCESS; return fw; } enum samsung_error_t samsung_write(samsung_write_t write, samsung_printf_t printf, void *user, struct samsung_firmware_t *fw) { struct yp_header_t yp_hdr; struct yp_md5_t yp_md5; // write header strncpy(yp_hdr.signature, YP_SIGNATURE, sizeof(yp_hdr.signature)); strncpy(yp_hdr.version, fw->version, sizeof(yp_hdr.version)); strncpy(yp_hdr.region, fw->region, sizeof(yp_hdr.region)); strncpy(yp_hdr.extra, fw->extra, sizeof(yp_hdr.extra)); strncpy(yp_hdr.model, fw->model, sizeof(yp_hdr.model)); yp_hdr.datasize = fw->data_size; printf(user, false, "Model: %s\n", yp_hdr.model); printf(user, false, "Version: %s %s %s\n", yp_hdr.version, yp_hdr.region, yp_hdr.extra); if(write(user, 0, &yp_hdr, sizeof(yp_hdr)) != sizeof(yp_hdr)) { printf(user, true, "Cannot write header\n"); return SAMSUNG_WRITE_ERROR; } // encrypt data cyclic_xor(fw->data, fw->data_size, g_yp_key, sizeof(g_yp_key)); // compute MD5 MD5_CTX c; MD5_Init(&c); MD5_Update(&c, fw->data, fw->data_size); MD5_Final(yp_md5.md5, &c); // write data if(write(user, sizeof(yp_hdr), fw->data, fw->data_size) != fw->data_size) { // decrypt data so that the firmware data is the same after the call cyclic_xor(fw->data, fw->data_size, g_yp_key, sizeof(g_yp_key)); printf(user, true, "Cannot write data\n"); return SAMSUNG_WRITE_ERROR; } // decrypt data so that the firmware data is the same after the call cyclic_xor(fw->data, fw->data_size, g_yp_key, sizeof(g_yp_key)); // write md5 if(write(user, sizeof(yp_hdr) + fw->data_size, &yp_md5, sizeof(yp_md5)) != sizeof(yp_md5)) { printf(user, true, "Cannot write md5\n"); return SAMSUNG_WRITE_ERROR; } return SAMSUNG_SUCCESS; } void samsung_free(struct samsung_firmware_t *fw) { if(fw) { free(fw->data); free(fw); } }