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-rw-r--r--src/core/crypto/aes_util.cpp112
1 files changed, 112 insertions, 0 deletions
diff --git a/src/core/crypto/aes_util.cpp b/src/core/crypto/aes_util.cpp
new file mode 100644
index 000000000..4690af5f8
--- /dev/null
+++ b/src/core/crypto/aes_util.cpp
@@ -0,0 +1,112 @@
+// Copyright 2018 yuzu emulator team
+// Licensed under GPLv2 or any later version
+// Refer to the license.txt file included.
+
+#include <mbedtls/cipher.h>
+#include "core/crypto/aes_util.h"
+#include "core/crypto/key_manager.h"
+
+namespace Core::Crypto {
+
+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) {
+ size_t written = 0;
+
+ const auto context = op == Op::Encrypt ? &ctx->encryption_context : &ctx->decryption_context;
+
+ mbedtls_cipher_reset(context);
+
+ 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) {
+ if (size % sector_size > 0) {
+ LOG_CRITICAL(Crypto, "Data size must be a multiple of sector size.");
+ return;
+ }
+
+ 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 <typename Key, size_t KeySize>
+std::vector<u8> AESCipher<Key, KeySize>::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;
+}
+
+template class AESCipher<Key128>;
+template class AESCipher<Key256>;
+} // namespace Core::Crypto \ No newline at end of file