/*
* Copyright (c) 2018-2019 Atmosphère-NX
*
* This program is free software; you can redistribute it and/or modify it
* under the terms and conditions of the GNU General Public License,
* version 2, as published by the Free Software Foundation.
*
* This program is distributed in the hope it will be useful, but WITHOUT
* ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
* FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
* more details.
*
* You should have received a copy of the GNU General Public License
* along with this program. If not, see <http://www.gnu.org/licenses/>.
*/
#include <stdio.h>
#include "key_derivation.h"
#include "masterkey.h"
#include "se.h"
#include "exocfg.h"
#include "fuse.h"
#include "extkeys.h"
#include "utils.h"
#define AL16 ALIGN(16)
static const uint8_t AL16 keyblob_seeds[MASTERKEY_REVISION_MAX][0x10] = {
{0xDF, 0x20, 0x6F, 0x59, 0x44, 0x54, 0xEF, 0xDC, 0x70, 0x74, 0x48, 0x3B, 0x0D, 0xED, 0x9F, 0xD3}, /* Keyblob seed 00. */
{0x0C, 0x25, 0x61, 0x5D, 0x68, 0x4C, 0xEB, 0x42, 0x1C, 0x23, 0x79, 0xEA, 0x82, 0x25, 0x12, 0xAC}, /* Keyblob seed 01. */
{0x33, 0x76, 0x85, 0xEE, 0x88, 0x4A, 0xAE, 0x0A, 0xC2, 0x8A, 0xFD, 0x7D, 0x63, 0xC0, 0x43, 0x3B}, /* Keyblob seed 02. */
{0x2D, 0x1F, 0x48, 0x80, 0xED, 0xEC, 0xED, 0x3E, 0x3C, 0xF2, 0x48, 0xB5, 0x65, 0x7D, 0xF7, 0xBE}, /* Keyblob seed 03. */
{0xBB, 0x5A, 0x01, 0xF9, 0x88, 0xAF, 0xF5, 0xFC, 0x6C, 0xFF, 0x07, 0x9E, 0x13, 0x3C, 0x39, 0x80}, /* Keyblob seed 04. */
{0xD8, 0xCC, 0xE1, 0x26, 0x6A, 0x35, 0x3F, 0xCC, 0x20, 0xF3, 0x2D, 0x3B, 0x51, 0x7D, 0xE9, 0xC0} /* Keyblob seed 05. */
};
static const uint8_t AL16 keyblob_mac_seed[0x10] = {
0x59, 0xC7, 0xFB, 0x6F, 0xBE, 0x9B, 0xBE, 0x87, 0x65, 0x6B, 0x15, 0xC0, 0x53, 0x73, 0x36, 0xA5
};
static const uint8_t AL16 masterkey_seed[0x10] = {
0xD8, 0xA2, 0x41, 0x0A, 0xC6, 0xC5, 0x90, 0x01, 0xC6, 0x1D, 0x6A, 0x26, 0x7C, 0x51, 0x3F, 0x3C
};
static const uint8_t AL16 devicekey_seed[0x10] = {
0x4F, 0x02, 0x5F, 0x0E, 0xB6, 0x6D, 0x11, 0x0E, 0xDC, 0x32, 0x7D, 0x41, 0x86, 0xC2, 0xF4, 0x78
};
static const uint8_t AL16 devicekey_4x_seed[0x10] = {
0x0C, 0x91, 0x09, 0xDB, 0x93, 0x93, 0x07, 0x81, 0x07, 0x3C, 0xC4, 0x16, 0x22, 0x7C, 0x6C, 0x28
};
static const uint8_t AL16 masterkey_4x_seed[0x10] = {
0x2D, 0xC1, 0xF4, 0x8D, 0xF3, 0x5B, 0x69, 0x33, 0x42, 0x10, 0xAC, 0x65, 0xDA, 0x90, 0x46, 0x66
};
/* TODO: Bother adding 8.1.0 here? We'll never call into here... */
static const uint8_t AL16 new_master_kek_seeds[MASTERKEY_REVISION_700_800 - MASTERKEY_REVISION_600_610][0x10] = {
{0x37, 0x4B, 0x77, 0x29, 0x59, 0xB4, 0x04, 0x30, 0x81, 0xF6, 0xE5, 0x8C, 0x6D, 0x36, 0x17, 0x9A}, /* MasterKek seed 06. */
{0x9A, 0x3E, 0xA9, 0xAB, 0xFD, 0x56, 0x46, 0x1C, 0x9B, 0xF6, 0x48, 0x7F, 0x5C, 0xFA, 0x09, 0x5C}, /* MasterKek seed 07. */
};
static nx_dec_keyblob_t AL16 g_dec_keyblobs[32];
static int get_keyblob(nx_keyblob_t *dst, uint32_t revision, const nx_keyblob_t *keyblobs, uint32_t available_revision) {
if (revision >= 0x20) {
return -1;
/* TODO: what should we do? */
}
if (keyblobs != NULL) {
*dst = keyblobs[revision];
} else {
return -1;
/* TODO: what should we do? */
}
return 0;
}
static bool safe_memcmp(uint8_t *a, uint8_t *b, size_t sz) {
uint8_t different = 0;
for (unsigned int i = 0; i < sz; i++) {
different |= a[i] ^ b[i];
}
return different != 0;
}
static int decrypt_keyblob(const nx_keyblob_t *keyblobs, uint32_t revision, uint32_t available_revision) {
nx_keyblob_t AL16 keyblob;
uint8_t AL16 work_buffer[0x10];
unsigned int keyslot = revision == MASTERKEY_REVISION_100_230 ? 0xF : KEYSLOT_SWITCH_TEMPKEY;
if (get_keyblob(&keyblob, revision, keyblobs, available_revision) != 0) {
return -1;
}
se_aes_ecb_decrypt_block(0xD, work_buffer, 0x10, keyblob_seeds[revision], 0x10);
decrypt_data_into_keyslot(keyslot, 0xE, work_buffer, 0x10);
decrypt_data_into_keyslot(0xB, keyslot, keyblob_mac_seed, 0x10);
/* Validate keyblob. */
se_compute_aes_128_cmac(0xB, work_buffer, 0x10, keyblob.mac + sizeof(keyblob.mac), sizeof(keyblob) - sizeof(keyblob.mac));
if (safe_memcmp(keyblob.mac, work_buffer, 0x10)) {
return -1;
}
/* Decrypt keyblob. */
se_aes_ctr_crypt(keyslot, &g_dec_keyblobs[revision], sizeof(g_dec_keyblobs[revision]), keyblob.data, sizeof(keyblob.data), keyblob.ctr, sizeof(keyblob.ctr));
return 0;
}
int load_package1_key(uint32_t revision) {
if (revision > MASTERKEY_REVISION_600_610) {
return -1;
}
set_aes_keyslot(0xB, g_dec_keyblobs[revision].package1_key, 0x10);
return 0;
}
/* Derive all Switch keys. */
int derive_nx_keydata(uint32_t target_firmware, const nx_keyblob_t *keyblobs, uint32_t available_revision, const void *tsec_key, void *tsec_root_keys, unsigned int *out_keygen_type) {
uint8_t AL16 work_buffer[0x10];
uint8_t AL16 zeroes[0x10] = {0};
/* Initialize keygen type. */
*out_keygen_type = 0;
/* TODO: Set keyslot flags properly in preparation of derivation. */
set_aes_keyslot_flags(0xE, 0x15);
set_aes_keyslot_flags(0xD, 0x15);
/* Set the TSEC key. */
set_aes_keyslot(0xD, tsec_key, 0x10);
/* Decrypt all keyblobs, setting keyslot 0xF correctly. */
for (unsigned int rev = 0; rev <= MASTERKEY_REVISION_600_610; rev++) {
int ret = decrypt_keyblob(keyblobs, rev, available_revision);
if (ret) {
return ret;
}
}
/* Do 6.2.0+ keygen. */
if (target_firmware >= ATMOSPHERE_TARGET_FIRMWARE_620) {
uint32_t desired_keyblob;
switch (target_firmware) {
case ATMOSPHERE_TARGET_FIRMWARE_620:
desired_keyblob = MASTERKEY_REVISION_620;
break;
case ATMOSPHERE_TARGET_FIRMWARE_700:
case ATMOSPHERE_TARGET_FIRMWARE_800:
desired_keyblob = MASTERKEY_REVISION_700_800;
break;
case ATMOSPHERE_TARGET_FIRMWARE_810:
desired_keyblob = MASTERKEY_REVISION_810;
/* Fallthrough */
case ATMOSPHERE_TARGET_FIRMWARE_900:
desired_keyblob = MASTERKEY_REVISION_900;
/* Fallthrough */
case ATMOSPHERE_TARGET_FIRMWARE_910:
desired_keyblob = MASTERKEY_REVISION_910_CURRENT;
break;
default:
fatal_error("Unknown target firmware: %02x!", target_firmware);
break;
}
/* Try emulation result. */
for (unsigned int rev = MASTERKEY_REVISION_620; rev < MASTERKEY_REVISION_MAX; rev++) {
void *tsec_root_key = (void *)((uintptr_t)tsec_root_keys + 0x10 * (rev - MASTERKEY_REVISION_620));
if (memcmp(tsec_root_key, zeroes, 0x10) != 0) {
/* We got a valid key from emulation. */
set_aes_keyslot(0xC, tsec_root_key, 0x10);
se_aes_ecb_decrypt_block(0xC, work_buffer, 0x10, new_master_kek_seeds[rev - MASTERKEY_REVISION_620], 0x10);
memcpy(g_dec_keyblobs[rev].master_kek, work_buffer, 0x10);
}
}
if (memcmp(g_dec_keyblobs[desired_keyblob].master_kek, zeroes, 0x10) == 0) {
/* Try reading the keys from a file. */
const char *keyfile = fuse_get_retail_type() != 0 ? "atmosphere/prod.keys" : "atmosphere/dev.keys";
FILE *extkey_file = fopen(keyfile, "r");
AL16 fusee_extkeys_t extkeys = {0};
if (extkey_file == NULL) {
fatal_error("Error: failed to read %s, needed for 6.2.0+ key derivation!", keyfile);
}
extkeys_initialize_keyset(&extkeys, extkey_file);
fclose(extkey_file);
for (unsigned int rev = MASTERKEY_REVISION_620; rev < MASTERKEY_REVISION_MAX; rev++) {
if (memcmp(extkeys.tsec_root_keys[rev - MASTERKEY_REVISION_620], zeroes, 0x10) != 0) {
set_aes_keyslot(0xC, extkeys.tsec_root_keys[rev - MASTERKEY_REVISION_620], 0x10);
se_aes_ecb_decrypt_block(0xC, work_buffer, 0x10, new_master_kek_seeds[rev - MASTERKEY_REVISION_620], 0x10);
memcpy(g_dec_keyblobs[rev].master_kek, work_buffer, 0x10);
} else {
memcpy(g_dec_keyblobs[rev].master_kek, extkeys.master_keks[rev], 0x10);
}
}
}
if (memcmp(g_dec_keyblobs[available_revision].master_kek, zeroes, 0x10) == 0) {
fatal_error("Error: failed to derive master_kek_%02x!", available_revision);
}
}
/* Clear the SBK. */
clear_aes_keyslot(0xE);
/* Get needed data. */
set_aes_keyslot(0xC, g_dec_keyblobs[available_revision].master_kek, 0x10);
/* Also set the Package1 key for the revision that is stored on the eMMC boot0 partition. */
if (target_firmware < ATMOSPHERE_TARGET_FIRMWARE_620) {
load_package1_key(available_revision);
}
/* Derive keys for Exosphere, lock critical keyslots. */
switch (target_firmware) {
case ATMOSPHERE_TARGET_FIRMWARE_100:
case ATMOSPHERE_TARGET_FIRMWARE_200:
case ATMOSPHERE_TARGET_FIRMWARE_300:
decrypt_data_into_keyslot(0xD, 0xF, devicekey_seed, 0x10);
decrypt_data_into_keyslot(0xC, 0xC, masterkey_seed, 0x10);
break;
case ATMOSPHERE_TARGET_FIRMWARE_400:
decrypt_data_into_keyslot(0xD, 0xF, devicekey_4x_seed, 0x10);
decrypt_data_into_keyslot(0xF, 0xF, devicekey_seed, 0x10);
decrypt_data_into_keyslot(0xE, 0xC, masterkey_4x_seed, 0x10);
decrypt_data_into_keyslot(0xC, 0xC, masterkey_seed, 0x10);
break;
case ATMOSPHERE_TARGET_FIRMWARE_500:
case ATMOSPHERE_TARGET_FIRMWARE_600:
case ATMOSPHERE_TARGET_FIRMWARE_620:
case ATMOSPHERE_TARGET_FIRMWARE_700:
case ATMOSPHERE_TARGET_FIRMWARE_800:
case ATMOSPHERE_TARGET_FIRMWARE_810:
case ATMOSPHERE_TARGET_FIRMWARE_900:
decrypt_data_into_keyslot(0xA, 0xF, devicekey_4x_seed, 0x10);
decrypt_data_into_keyslot(0xF, 0xF, devicekey_seed, 0x10);
decrypt_data_into_keyslot(0xE, 0xC, masterkey_4x_seed, 0x10);
decrypt_data_into_keyslot(0xC, 0xC, masterkey_seed, 0x10);
break;
default:
return -1;
}
/* Setup master key revision, derive older master keys for use. */
return mkey_detect_revision(fuse_get_retail_type() != 0);
}
/* Sets final keyslot flags, for handover to TZ/Exosphere. Setting these will prevent the BPMP from using the device key or master key. */
void finalize_nx_keydata(uint32_t target_firmware) {
set_aes_keyslot_flags(0xC, 0xFF);
set_aes_keyslot_flags((target_firmware >= ATMOSPHERE_TARGET_FIRMWARE_400) ? (KEYSLOT_SWITCH_4XOLDDEVICEKEY) : (KEYSLOT_SWITCH_DEVICEKEY), 0xFF);
}
static void generate_specific_aes_key(void *dst, const void *wrapped_key, bool should_mask, uint32_t target_firmware) {
unsigned int keyslot = (target_firmware >= ATMOSPHERE_TARGET_FIRMWARE_400) ? (KEYSLOT_SWITCH_4XOLDDEVICEKEY) : (KEYSLOT_SWITCH_DEVICEKEY);
if (fuse_get_bootrom_patch_version() < 0x7F) {
/* On dev units, use a fixed "all-zeroes" seed. */
/* Yes, this data really is all-zero in actual TrustZone .rodata. */
static const uint8_t AL16 dev_specific_aes_key_source[0x10] = {0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00};
static const uint8_t AL16 dev_specific_aes_key_ctr[0x10] = {0x3C, 0xD5, 0x92, 0xEC, 0x68, 0x31, 0x4A, 0x06, 0xD4, 0x1B, 0x0C, 0xD9, 0xF6, 0x2E, 0xD9, 0xE9};
static const uint8_t AL16 dev_specific_aes_key_mask[0x10] = {0xAC, 0xCA, 0x9A, 0xCA, 0xFF, 0x2E, 0xB9, 0x22, 0xCC, 0x1F, 0x4F, 0xAD, 0xDD, 0x77, 0x21, 0x1E};
se_aes_ctr_crypt(keyslot, dst, 0x10, dev_specific_aes_key_source, 0x10, dev_specific_aes_key_ctr, 0x10);
if (should_mask) {
for (unsigned int i = 0; i < 0x10; i++) {
((uint8_t *)dst)[i] ^= dev_specific_aes_key_mask[i];
}
}
} else {
/* On retail, standard kek->key decryption. */
static const uint8_t AL16 retail_specific_aes_key_source[0x10] = {0xE2, 0xD6, 0xB8, 0x7A, 0x11, 0x9C, 0xB8, 0x80, 0xE8, 0x22, 0x88, 0x8A, 0x46, 0xFB, 0xA1, 0x95};
decrypt_data_into_keyslot(KEYSLOT_SWITCH_TEMPKEY, keyslot, retail_specific_aes_key_source, 0x10);
se_aes_ecb_decrypt_block(KEYSLOT_SWITCH_TEMPKEY, dst, 0x10, wrapped_key, 0x10);
}
}
static void generate_personalized_aes_key_for_bis(void *dst, const void *wrapped_kek, const void *wrapped_key, uint32_t target_firmware) {
static const uint8_t AL16 kek_source[0x10] = {
0x4D, 0x87, 0x09, 0x86, 0xC4, 0x5D, 0x20, 0x72, 0x2F, 0xBA, 0x10, 0x53, 0xDA, 0x92, 0xE8, 0xA9
};
static const uint8_t AL16 key_source[0x10] = {
0x89, 0x61, 0x5E, 0xE0, 0x5C, 0x31, 0xB6, 0x80, 0x5F, 0xE5, 0x8F, 0x3D, 0xA2, 0x4F, 0x7A, 0xA8
};
unsigned int keyslot = (target_firmware >= ATMOSPHERE_TARGET_FIRMWARE_400) ? (KEYSLOT_SWITCH_4XOLDDEVICEKEY) : (KEYSLOT_SWITCH_DEVICEKEY);
/* Derive kek. */
decrypt_data_into_keyslot(KEYSLOT_SWITCH_TEMPKEY, keyslot, kek_source, 0x10);
decrypt_data_into_keyslot(KEYSLOT_SWITCH_TEMPKEY, KEYSLOT_SWITCH_TEMPKEY, wrapped_kek, 0x10);
/* Derive key. */
decrypt_data_into_keyslot(KEYSLOT_SWITCH_TEMPKEY, KEYSLOT_SWITCH_TEMPKEY, key_source, 0x10);
se_aes_ecb_decrypt_block(KEYSLOT_SWITCH_TEMPKEY, dst, 0x10, wrapped_key, 0x10);
}
void derive_bis_key(void *dst, BisPartition partition_id, uint32_t target_firmware) {
static const uint8_t AL16 key_source_for_bis[3][2][0x10] = {
{
{0xF8, 0x3F, 0x38, 0x6E, 0x2C, 0xD2, 0xCA, 0x32, 0xA8, 0x9A, 0xB9, 0xAA, 0x29, 0xBF, 0xC7, 0x48},
{0x7D, 0x92, 0xB0, 0x3A, 0xA8, 0xBF, 0xDE, 0xE1, 0xA7, 0x4C, 0x3B, 0x6E, 0x35, 0xCB, 0x71, 0x06}
},
{
{0x41, 0x00, 0x30, 0x49, 0xDD, 0xCC, 0xC0, 0x65, 0x64, 0x7A, 0x7E, 0xB4, 0x1E, 0xED, 0x9C, 0x5F},
{0x44, 0x42, 0x4E, 0xDA, 0xB4, 0x9D, 0xFC, 0xD9, 0x87, 0x77, 0x24, 0x9A, 0xDC, 0x9F, 0x7C, 0xA4}
},
{
{0x52, 0xC2, 0xE9, 0xEB, 0x09, 0xE3, 0xEE, 0x29, 0x32, 0xA1, 0x0C, 0x1F, 0xB6, 0xA0, 0x92, 0x6C},
{0x4D, 0x12, 0xE1, 0x4B, 0x2A, 0x47, 0x4C, 0x1C, 0x09, 0xCB, 0x03, 0x59, 0xF0, 0x15, 0xF4, 0xE4}
}
};
static const uint8_t AL16 bis_kek_source[0x10] = {0x34, 0xC1, 0xA0, 0xC4, 0x82, 0x58, 0xF8, 0xB4, 0xFA, 0x9E, 0x5E, 0x6A, 0xDA, 0xFC, 0x7E, 0x4F};
switch (partition_id) {
case BisPartition_Calibration:
generate_specific_aes_key(dst, key_source_for_bis[partition_id][0], false, target_firmware);
generate_specific_aes_key(dst + 0x10, key_source_for_bis[partition_id][1], false, target_firmware);
break;
case BisPartition_Safe:
case BisPartition_UserSystem:
generate_personalized_aes_key_for_bis(dst, bis_kek_source, key_source_for_bis[partition_id][0], target_firmware);
generate_personalized_aes_key_for_bis(dst + 0x10, bis_kek_source, key_source_for_bis[partition_id][1], target_firmware);
break;
default:
generic_panic();
}
}
