10e5356e9a
XTS with Nintendo Tweak will fail mysteriously if the sector size is not 0x4000. Upgrade the critical log to an assert to prevent undefined behavior.
113 lines
4.3 KiB
C++
113 lines
4.3 KiB
C++
// Copyright 2018 yuzu emulator team
|
|
// Licensed under GPLv2 or any later version
|
|
// Refer to the license.txt file included.
|
|
|
|
#include <mbedtls/cipher.h>
|
|
#include "common/assert.h"
|
|
#include "common/logging/log.h"
|
|
#include "core/crypto/aes_util.h"
|
|
#include "core/crypto/key_manager.h"
|
|
|
|
namespace Core::Crypto {
|
|
namespace {
|
|
std::vector<u8> CalculateNintendoTweak(size_t sector_id) {
|
|
std::vector<u8> out(0x10);
|
|
for (size_t i = 0xF; i <= 0xF; --i) {
|
|
out[i] = sector_id & 0xFF;
|
|
sector_id >>= 8;
|
|
}
|
|
return out;
|
|
}
|
|
} // Anonymous namespace
|
|
|
|
static_assert(static_cast<size_t>(Mode::CTR) == static_cast<size_t>(MBEDTLS_CIPHER_AES_128_CTR),
|
|
"CTR has incorrect value.");
|
|
static_assert(static_cast<size_t>(Mode::ECB) == static_cast<size_t>(MBEDTLS_CIPHER_AES_128_ECB),
|
|
"ECB has incorrect value.");
|
|
static_assert(static_cast<size_t>(Mode::XTS) == static_cast<size_t>(MBEDTLS_CIPHER_AES_128_XTS),
|
|
"XTS has incorrect value.");
|
|
|
|
// Structure to hide mbedtls types from header file
|
|
struct CipherContext {
|
|
mbedtls_cipher_context_t encryption_context;
|
|
mbedtls_cipher_context_t decryption_context;
|
|
};
|
|
|
|
template <typename Key, size_t KeySize>
|
|
Crypto::AESCipher<Key, KeySize>::AESCipher(Key key, Mode mode)
|
|
: ctx(std::make_unique<CipherContext>()) {
|
|
mbedtls_cipher_init(&ctx->encryption_context);
|
|
mbedtls_cipher_init(&ctx->decryption_context);
|
|
|
|
ASSERT_MSG((mbedtls_cipher_setup(
|
|
&ctx->encryption_context,
|
|
mbedtls_cipher_info_from_type(static_cast<mbedtls_cipher_type_t>(mode))) ||
|
|
mbedtls_cipher_setup(
|
|
&ctx->decryption_context,
|
|
mbedtls_cipher_info_from_type(static_cast<mbedtls_cipher_type_t>(mode)))) == 0,
|
|
"Failed to initialize mbedtls ciphers.");
|
|
|
|
ASSERT(
|
|
!mbedtls_cipher_setkey(&ctx->encryption_context, key.data(), KeySize * 8, MBEDTLS_ENCRYPT));
|
|
ASSERT(
|
|
!mbedtls_cipher_setkey(&ctx->decryption_context, key.data(), KeySize * 8, MBEDTLS_DECRYPT));
|
|
//"Failed to set key on mbedtls ciphers.");
|
|
}
|
|
|
|
template <typename Key, size_t KeySize>
|
|
AESCipher<Key, KeySize>::~AESCipher() {
|
|
mbedtls_cipher_free(&ctx->encryption_context);
|
|
mbedtls_cipher_free(&ctx->decryption_context);
|
|
}
|
|
|
|
template <typename Key, size_t KeySize>
|
|
void AESCipher<Key, KeySize>::SetIV(std::vector<u8> iv) {
|
|
ASSERT_MSG((mbedtls_cipher_set_iv(&ctx->encryption_context, iv.data(), iv.size()) ||
|
|
mbedtls_cipher_set_iv(&ctx->decryption_context, iv.data(), iv.size())) == 0,
|
|
"Failed to set IV on mbedtls ciphers.");
|
|
}
|
|
|
|
template <typename Key, size_t KeySize>
|
|
void AESCipher<Key, KeySize>::Transcode(const u8* src, size_t size, u8* dest, Op op) const {
|
|
auto* const context = op == Op::Encrypt ? &ctx->encryption_context : &ctx->decryption_context;
|
|
|
|
mbedtls_cipher_reset(context);
|
|
|
|
size_t written = 0;
|
|
if (mbedtls_cipher_get_cipher_mode(context) == MBEDTLS_MODE_XTS) {
|
|
mbedtls_cipher_update(context, src, size, dest, &written);
|
|
if (written != size) {
|
|
LOG_WARNING(Crypto, "Not all data was decrypted requested={:016X}, actual={:016X}.",
|
|
size, written);
|
|
}
|
|
} else {
|
|
const auto block_size = mbedtls_cipher_get_block_size(context);
|
|
|
|
for (size_t offset = 0; offset < size; offset += block_size) {
|
|
auto length = std::min<size_t>(block_size, size - offset);
|
|
mbedtls_cipher_update(context, src + offset, length, dest + offset, &written);
|
|
if (written != length) {
|
|
LOG_WARNING(Crypto, "Not all data was decrypted requested={:016X}, actual={:016X}.",
|
|
length, written);
|
|
}
|
|
}
|
|
}
|
|
|
|
mbedtls_cipher_finish(context, nullptr, nullptr);
|
|
}
|
|
|
|
template <typename Key, size_t KeySize>
|
|
void AESCipher<Key, KeySize>::XTSTranscode(const u8* src, size_t size, u8* dest, size_t sector_id,
|
|
size_t sector_size, Op op) {
|
|
ASSERT_MSG(size % sector_size == 0, "XTS decryption size must be a multiple of sector size.");
|
|
|
|
for (size_t i = 0; i < size; i += sector_size) {
|
|
SetIV(CalculateNintendoTweak(sector_id++));
|
|
Transcode<u8, u8>(src + i, sector_size, dest + i, op);
|
|
}
|
|
}
|
|
|
|
template class AESCipher<Key128>;
|
|
template class AESCipher<Key256>;
|
|
} // namespace Core::Crypto
|