コード例 #1
0
        public byte[] DecryptData(EncryptedPacket encryptedPacket, RSAWithRSAParameterKey rsaParams)
        {
            var decryptedSessionKey = rsaParams.DecryptData(encryptedPacket.EncryptedSessionKey);

            var decryptedData = _aes.Decrypt(encryptedPacket.EncryptedData, decryptedSessionKey, encryptedPacket.Iv);

            return(decryptedData);
        }
コード例 #2
0
        public EncryptedPacket EncryptData(byte[] original, RSAWithRSAParameterKey rsaParams)
        {
            var sessionKey      = _aes.GenerateRandomNumber(32);
            var encryptedPacket = new EncryptedPacket {
                Iv = _aes.GenerateRandomNumber(16)
            };

            encryptedPacket.EncryptedData       = _aes.Encrypt(original, sessionKey, encryptedPacket.Iv);
            encryptedPacket.EncryptedSessionKey = rsaParams.EncryptData(sessionKey);
            return(encryptedPacket);
        }
        public EncryptedPacket EncryptData(byte[] original, RSAWithRSAParameterKey rsaParams, DigitalSignature signature)
        {
            var sessionKey      = _aes.GenerateRandomNumber(32);
            var encryptedPacket = new EncryptedPacket {
                Iv = _aes.GenerateRandomNumber(16)
            };

            encryptedPacket.EncryptedData       = _aes.Encrypt(original, sessionKey, encryptedPacket.Iv);
            encryptedPacket.EncryptedSessionKey = rsaParams.EncryptData(sessionKey);

            using (var hmac = new HMACSHA256(sessionKey))
            {
                encryptedPacket.Hmac = hmac.ComputeHash(encryptedPacket.EncryptedData);
            }
            encryptedPacket.Signature = signature.SignData(encryptedPacket.Hmac);

            return(encryptedPacket);
        }
        public byte[] DecryptData(EncryptedPacket encryptedPacket, RSAWithRSAParameterKey rsaParams, DigitalSignature digitalSignature)
        {
            var decryptedSessionKey = rsaParams.DecryptData(encryptedPacket.EncryptedSessionKey);

            using (var hmac = new HMACSHA256(decryptedSessionKey))
            {
                var hmacToCheck = hmac.ComputeHash(encryptedPacket.EncryptedData);
                if (!Compare(encryptedPacket.Hmac, hmacToCheck))
                {
                    throw new CryptographicException("HMAC for encryption does not match with encrypted packet");
                }
                if (!digitalSignature.VerifySignature(encryptedPacket.Hmac, hmacToCheck))
                {
                    throw new CryptographicException("Digital Signature can not be verified");
                }
            }
            var decryptedData = _aes.Decrypt(encryptedPacket.EncryptedData, decryptedSessionKey, encryptedPacket.Iv);

            return(decryptedData);
        }