private byte[] EncryptSessionInfo(byte[] sessionInfo, SecureRandom random)
{
if (pubKey.Algorithm != PublicKeyAlgorithmTag.EC)
{
IBufferedCipher cipher;
switch (pubKey.Algorithm)
{
case PublicKeyAlgorithmTag.RsaGeneral:
case PublicKeyAlgorithmTag.RsaEncrypt:
cipher = CipherUtilities.GetCipher("RSA//PKCS1Padding");
break;
case PublicKeyAlgorithmTag.ElGamalEncrypt:
case PublicKeyAlgorithmTag.ElGamalGeneral:
cipher = CipherUtilities.GetCipher("ElGamal/ECB/PKCS1Padding");
break;
case PublicKeyAlgorithmTag.Dsa:
throw new PgpException("Can't use DSA for encryption.");
case PublicKeyAlgorithmTag.ECDsa:
throw new PgpException("Can't use ECDSA for encryption.");
default:
throw new PgpException(string.Concat((object)"unknown asymmetric algorithm: ", (object)pubKey.Algorithm));
}
AsymmetricKeyParameter parameters = pubKey.GetKey();
cipher.Init(forEncryption: true, new ParametersWithRandom(parameters, random));
return(cipher.DoFinal(sessionInfo));
}
ECDHPublicBcpgKey eCDHPublicBcpgKey = (ECDHPublicBcpgKey)pubKey.PublicKeyPacket.Key;
IAsymmetricCipherKeyPairGenerator keyPairGenerator = GeneratorUtilities.GetKeyPairGenerator("ECDH");
keyPairGenerator.Init(new ECKeyGenerationParameters(eCDHPublicBcpgKey.CurveOid, random));
AsymmetricCipherKeyPair asymmetricCipherKeyPair = keyPairGenerator.GenerateKeyPair();
ECPrivateKeyParameters eCPrivateKeyParameters = (ECPrivateKeyParameters)asymmetricCipherKeyPair.Private;
ECPublicKeyParameters eCPublicKeyParameters = (ECPublicKeyParameters)asymmetricCipherKeyPair.Public;
ECPublicKeyParameters eCPublicKeyParameters2 = (ECPublicKeyParameters)pubKey.GetKey();
ECPoint s = eCPublicKeyParameters2.Q.Multiply(eCPrivateKeyParameters.D).Normalize();
KeyParameter parameters2 = new KeyParameter(Rfc6637Utilities.CreateKey(pubKey.PublicKeyPacket, s));
IWrapper wrapper = PgpUtilities.CreateWrapper(eCDHPublicBcpgKey.SymmetricKeyAlgorithm);
wrapper.Init(forWrapping: true, new ParametersWithRandom(parameters2, random));
byte[] array = PgpPad.PadSessionData(sessionInfo);
byte[] array2 = wrapper.Wrap(array, 0, array.Length);
byte[] encoded = new MPInteger(new BigInteger(1, eCPublicKeyParameters.Q.GetEncoded(compressed: false))).GetEncoded();
byte[] array3 = new byte[encoded.Length + 1 + array2.Length];
global::System.Array.Copy((global::System.Array)encoded, 0, (global::System.Array)array3, 0, encoded.Length);
array3[encoded.Length] = (byte)array2.Length;
global::System.Array.Copy((global::System.Array)array2, 0, (global::System.Array)array3, encoded.Length + 1, array2.Length);
return(array3);
}
private byte[] EncryptSessionInfo(byte[] sessionInfo, SecureRandom random)
{
if (pubKey.Algorithm != PublicKeyAlgorithmTag.ECDH)
{
IBufferedCipher c;
switch (pubKey.Algorithm)
{
case PublicKeyAlgorithmTag.RsaEncrypt:
case PublicKeyAlgorithmTag.RsaGeneral:
c = CipherUtilities.GetCipher("RSA//PKCS1Padding");
break;
case PublicKeyAlgorithmTag.ElGamalEncrypt:
case PublicKeyAlgorithmTag.ElGamalGeneral:
c = CipherUtilities.GetCipher("ElGamal/ECB/PKCS1Padding");
break;
case PublicKeyAlgorithmTag.Dsa:
throw new PgpException("Can't use DSA for encryption.");
case PublicKeyAlgorithmTag.ECDsa:
throw new PgpException("Can't use ECDSA for encryption.");
default:
throw new PgpException("unknown asymmetric algorithm: " + pubKey.Algorithm);
}
AsymmetricKeyParameter akp = pubKey.GetKey();
c.Init(true, new ParametersWithRandom(akp, random));
return(c.DoFinal(sessionInfo));
}
ECDHPublicBcpgKey ecKey = (ECDHPublicBcpgKey)pubKey.PublicKeyPacket.Key;
// Generate the ephemeral key pair
IAsymmetricCipherKeyPairGenerator gen = GeneratorUtilities.GetKeyPairGenerator("ECDH");
gen.Init(new ECKeyGenerationParameters(ecKey.CurveOid, random));
AsymmetricCipherKeyPair ephKp = gen.GenerateKeyPair();
ECPrivateKeyParameters ephPriv = (ECPrivateKeyParameters)ephKp.Private;
ECPublicKeyParameters ephPub = (ECPublicKeyParameters)ephKp.Public;
ECPublicKeyParameters pub = (ECPublicKeyParameters)pubKey.GetKey();
ECPoint S = pub.Q.Multiply(ephPriv.D).Normalize();
KeyParameter key = new KeyParameter(Rfc6637Utilities.CreateKey(pubKey.PublicKeyPacket, S));
IWrapper w = PgpUtilities.CreateWrapper(ecKey.SymmetricKeyAlgorithm);
w.Init(true, new ParametersWithRandom(key, random));
byte[] paddedSessionData = PgpPad.PadSessionData(sessionInfo);
byte[] C = w.Wrap(paddedSessionData, 0, paddedSessionData.Length);
byte[] VB = new MPInteger(new BigInteger(1, ephPub.Q.GetEncoded(false))).GetEncoded();
byte[] rv = new byte[VB.Length + 1 + C.Length];
Array.Copy(VB, 0, rv, 0, VB.Length);
rv[VB.Length] = (byte)C.Length;
Array.Copy(C, 0, rv, VB.Length + 1, C.Length);
return(rv);
}
