private void ProcessKeyExchange(KeyExchangeRequest Request)
{
RSA RSAEncryption = RSA.Create();
RSAEncryption.KeySize = Request.RSAKeySize;
RSAParameters PublicParameters = new RSAParameters()
{
Exponent = Request.RSAExponent, Modulus = Request.RSAModulus
};
RSAEncryption.ImportParameters(PublicParameters);
Cryptor = new AesManaged();
Cryptor.KeySize = Request.AESKeySize;
Cryptor.GenerateIV();
Cryptor.GenerateKey();
Cryptor.Mode = CipherMode.CBC;
Cryptor.Padding = PaddingMode.PKCS7;
KeyExchangeResponse Response = new KeyExchangeResponse()
{
Accepted = true, EncryptedAESIV = RSAEncryption.Encrypt(Cryptor.IV, RSAEncryptionPadding.Pkcs1), EncryptedAESKey = RSAEncryption.Encrypt(Cryptor.Key, RSAEncryptionPadding.Pkcs1), ID = Request.ID
};
Send(Response);
}
public async Task <bool> InitializeEncryption(RSAParameters?Parameters = null, int AESKeySize = 256)
{
RSA RSAEncryption = RSA.Create();
RSAParameters PublicParameters;
RSAEncryption.KeySize = Parameters?.D?.Length * 8 ?? 4096;
if (Parameters != null)
{
RSAEncryption.ImportParameters(Parameters.Value);
}
PublicParameters = RSAEncryption.ExportParameters(false);
KeyExchangeRequest Request = new KeyExchangeRequest()
{
RSAKeySize = RSAEncryption.KeySize, AESKeySize = AESKeySize, RSAExponent = PublicParameters.Exponent, RSAModulus = PublicParameters.Modulus
};
KeyExchangeResponse Response = await Send <KeyExchangeResponse>(Request);
if (Response?.Accepted ?? false)
{
Cryptor = new AesManaged();
Cryptor.KeySize = AESKeySize;
Cryptor.IV = RSAEncryption.Decrypt(Response.EncryptedAESIV, RSAEncryptionPadding.Pkcs1);
Cryptor.Key = RSAEncryption.Decrypt(Response.EncryptedAESKey, RSAEncryptionPadding.Pkcs1);
Cryptor.Mode = CipherMode.CBC;
Cryptor.Padding = PaddingMode.PKCS7;
return(true);
}
return(false);
}
