| /* |
| * Copyright (C) 2020 Sony Interactive Entertainment Inc. |
| * |
| * Redistribution and use in source and binary forms, with or without |
| * modification, are permitted provided that the following conditions |
| * are met: |
| * 1. Redistributions of source code must retain the above copyright |
| * notice, this list of conditions and the following disclaimer. |
| * 2. Redistributions in binary form must reproduce the above copyright |
| * notice, this list of conditions and the following disclaimer in the |
| * documentation and/or other materials provided with the distribution. |
| * |
| * THIS SOFTWARE IS PROVIDED BY APPLE INC. AND ITS CONTRIBUTORS ``AS IS'' |
| * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, |
| * THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR |
| * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL APPLE INC. OR ITS CONTRIBUTORS |
| * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR |
| * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF |
| * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS |
| * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN |
| * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) |
| * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF |
| * THE POSSIBILITY OF SUCH DAMAGE. |
| */ |
| |
| #include "config.h" |
| #include "CryptoAlgorithmAES_GCM.h" |
| |
| #if ENABLE(WEB_CRYPTO) |
| |
| #include "CryptoAlgorithmAesGcmParams.h" |
| #include "CryptoKeyAES.h" |
| #include "OpenSSLCryptoUniquePtr.h" |
| #include <openssl/evp.h> |
| |
| namespace WebCore { |
| |
| static const EVP_CIPHER* aesAlgorithm(size_t keySize) |
| { |
| if (keySize * 8 == 128) |
| return EVP_aes_128_gcm(); |
| |
| if (keySize * 8 == 192) |
| return EVP_aes_192_gcm(); |
| |
| if (keySize * 8 == 256) |
| return EVP_aes_256_gcm(); |
| |
| return nullptr; |
| } |
| |
| static std::optional<Vector<uint8_t>> cryptEncrypt(const Vector<uint8_t>& key, const Vector<uint8_t>& iv, const Vector<uint8_t>& plainText, const Vector<uint8_t>& additionalData, uint8_t tagLength) |
| { |
| const EVP_CIPHER* algorithm = aesAlgorithm(key.size()); |
| if (!algorithm) |
| return std::nullopt; |
| |
| EvpCipherCtxPtr ctx; |
| int len; |
| |
| Vector<uint8_t> cipherText(plainText.size() + tagLength); |
| size_t tagOffset = plainText.size(); |
| |
| // Create and initialize the context |
| if (!(ctx = EvpCipherCtxPtr(EVP_CIPHER_CTX_new()))) |
| return std::nullopt; |
| |
| // Disable padding |
| if (1 != EVP_CIPHER_CTX_set_padding(ctx.get(), 0)) |
| return std::nullopt; |
| |
| // Initialize the encryption operation |
| if (1 != EVP_EncryptInit_ex(ctx.get(), algorithm, nullptr, nullptr, nullptr)) |
| return std::nullopt; |
| |
| // Set IV length |
| if (1 != EVP_CIPHER_CTX_ctrl(ctx.get(), EVP_CTRL_GCM_SET_IVLEN, iv.size(), nullptr)) |
| return std::nullopt; |
| |
| // Initialize key and IV |
| if (1 != EVP_EncryptInit_ex(ctx.get(), nullptr, nullptr, key.data(), iv.data())) |
| return std::nullopt; |
| |
| // Provide any AAD data |
| if (additionalData.size() > 0) { |
| if (1 != EVP_EncryptUpdate(ctx.get(), nullptr, &len, additionalData.data(), additionalData.size())) |
| return std::nullopt; |
| } |
| |
| // Provide the message to be encrypted, and obtain the encrypted output |
| if (1 != EVP_EncryptUpdate(ctx.get(), cipherText.data(), &len, plainText.data(), plainText.size())) |
| return std::nullopt; |
| |
| // Finalize the encryption. Normally ciphertext bytes may be written at |
| // this stage, but this does not occur in GCM mode |
| if (1 != EVP_EncryptFinal_ex(ctx.get(), cipherText.data() + len, &len)) |
| return std::nullopt; |
| |
| // Get the tag |
| if (1 != EVP_CIPHER_CTX_ctrl(ctx.get(), EVP_CTRL_GCM_GET_TAG, tagLength, cipherText.data() + tagOffset)) |
| return std::nullopt; |
| |
| return cipherText; |
| } |
| |
| static std::optional<Vector<uint8_t>> cryptDecrypt(const Vector<uint8_t>& key, const Vector<uint8_t>& iv, const Vector<uint8_t>& cipherText, const Vector<uint8_t>& additionalData, uint8_t tagLength) |
| { |
| const EVP_CIPHER* algorithm = aesAlgorithm(key.size()); |
| if (!algorithm) |
| return std::nullopt; |
| |
| EvpCipherCtxPtr ctx; |
| int len; |
| int plainTextLen; |
| int cipherTextLen = cipherText.size() - tagLength; |
| |
| Vector<uint8_t> plainText(cipherText.size()); |
| Vector<uint8_t> tag { cipherText.data() + cipherTextLen, tagLength }; |
| |
| // Create and initialize the context |
| if (!(ctx = EvpCipherCtxPtr(EVP_CIPHER_CTX_new()))) |
| return std::nullopt; |
| |
| // Disable padding |
| if (1 != EVP_CIPHER_CTX_set_padding(ctx.get(), 0)) |
| return std::nullopt; |
| |
| // Initialize the encryption operation |
| if (1 != EVP_DecryptInit_ex(ctx.get(), algorithm, nullptr, nullptr, nullptr)) |
| return std::nullopt; |
| |
| // Set IV length |
| if (1 != EVP_CIPHER_CTX_ctrl(ctx.get(), EVP_CTRL_GCM_SET_IVLEN, iv.size(), nullptr)) |
| return std::nullopt; |
| |
| // Initialize key and IV |
| if (1 != EVP_DecryptInit_ex(ctx.get(), nullptr, nullptr, key.data(), iv.data())) |
| return std::nullopt; |
| |
| // Provide any AAD data |
| if (additionalData.size() > 0) { |
| if (1 != EVP_DecryptUpdate(ctx.get(), nullptr, &len, additionalData.data(), additionalData.size())) |
| return std::nullopt; |
| } |
| |
| // Set expected tag value |
| if (1 != EVP_CIPHER_CTX_ctrl(ctx.get(), EVP_CTRL_GCM_SET_TAG, tag.size(), tag.data())) |
| return std::nullopt; |
| |
| // Provide the message to be encrypted, and obtain the encrypted output |
| if (1 != EVP_DecryptUpdate(ctx.get(), plainText.data(), &len, cipherText.data(), cipherTextLen)) |
| return std::nullopt; |
| plainTextLen = len; |
| |
| // Finalize the decryption |
| if (1 != EVP_DecryptFinal_ex(ctx.get(), plainText.data() + len, &len)) |
| return std::nullopt; |
| |
| plainTextLen += len; |
| |
| plainText.shrink(plainTextLen); |
| |
| return plainText; |
| } |
| |
| ExceptionOr<Vector<uint8_t>> CryptoAlgorithmAES_GCM::platformEncrypt(const CryptoAlgorithmAesGcmParams& parameters, const CryptoKeyAES& key, const Vector<uint8_t>& plainText) |
| { |
| auto output = cryptEncrypt(key.key(), parameters.ivVector(), plainText, parameters.additionalDataVector(), parameters.tagLength.value_or(0) / 8); |
| if (!output) |
| return Exception { OperationError }; |
| return WTFMove(*output); |
| } |
| |
| ExceptionOr<Vector<uint8_t>> CryptoAlgorithmAES_GCM::platformDecrypt(const CryptoAlgorithmAesGcmParams& parameters, const CryptoKeyAES& key, const Vector<uint8_t>& cipherText) |
| { |
| auto output = cryptDecrypt(key.key(), parameters.ivVector(), cipherText, parameters.additionalDataVector(), parameters.tagLength.value_or(0) / 8); |
| if (!output) |
| return Exception { OperationError }; |
| return WTFMove(*output); |
| } |
| |
| } // namespace WebCore |
| |
| #endif // ENABLE(WEB_CRYPTO) |