private byte[] RecoverSessionData(PgpPrivateKey privKey)
{
byte[][] encSessionKey = keyData.GetEncSessionKey();
if (keyData.Algorithm == PublicKeyAlgorithmTag.EC)
{
ECDHPublicBcpgKey eCDHPublicBcpgKey = (ECDHPublicBcpgKey)privKey.PublicKeyPacket.Key;
X9ECParameters x9ECParameters = ECKeyPairGenerator.FindECCurveByOid(eCDHPublicBcpgKey.CurveOid);
byte[] array = encSessionKey[0];
int num = (((array[0] & 0xFF) << 8) + (array[1] & 0xFF) + 7) / 8;
byte[] array2 = new byte[num];
global::System.Array.Copy((global::System.Array)array, 2, (global::System.Array)array2, 0, num);
byte[] array3 = new byte[array[num + 2]];
global::System.Array.Copy((global::System.Array)array, 2 + num + 1, (global::System.Array)array3, 0, array3.Length);
ECPoint eCPoint = x9ECParameters.Curve.DecodePoint(array2);
ECPrivateKeyParameters eCPrivateKeyParameters = (ECPrivateKeyParameters)privKey.Key;
ECPoint s = eCPoint.Multiply(eCPrivateKeyParameters.D).Normalize();
KeyParameter parameters = new KeyParameter(Rfc6637Utilities.CreateKey(privKey.PublicKeyPacket, s));
IWrapper wrapper = PgpUtilities.CreateWrapper(eCDHPublicBcpgKey.SymmetricKeyAlgorithm);
wrapper.Init(forWrapping: false, parameters);
return(PgpPad.UnpadSessionData(wrapper.Unwrap(array3, 0, array3.Length)));
}
IBufferedCipher keyCipher = GetKeyCipher(keyData.Algorithm);
try
{
keyCipher.Init(forEncryption: false, privKey.Key);
}
catch (InvalidKeyException exception)
{
throw new PgpException("error setting asymmetric cipher", exception);
}
if (keyData.Algorithm == PublicKeyAlgorithmTag.RsaEncrypt || keyData.Algorithm == PublicKeyAlgorithmTag.RsaGeneral)
{
byte[] array4 = encSessionKey[0];
keyCipher.ProcessBytes(array4, 2, array4.Length - 2);
}
else
{
ElGamalPrivateKeyParameters elGamalPrivateKeyParameters = (ElGamalPrivateKeyParameters)privKey.Key;
int size = (elGamalPrivateKeyParameters.Parameters.P.BitLength + 7) / 8;
ProcessEncodedMpi(keyCipher, size, encSessionKey[0]);
ProcessEncodedMpi(keyCipher, size, encSessionKey[1]);
}
try
{
return(keyCipher.DoFinal());
}
catch (global::System.Exception exception2)
{
throw new PgpException("exception decrypting secret key", exception2);
}
}
private byte[] RecoverSessionData(PgpPrivateKey privKey)
{
byte[][] secKeyData = keyData.GetEncSessionKey();
if (keyData.Algorithm == PublicKeyAlgorithmTag.ECDH)
{
ECDHPublicBcpgKey ecKey = (ECDHPublicBcpgKey)privKey.PublicKeyPacket.Key;
X9ECParameters x9Params = ECKeyPairGenerator.FindECCurveByOid(ecKey.CurveOid);
byte[] enc = secKeyData[0];
int pLen = ((((enc[0] & 0xff) << 8) + (enc[1] & 0xff)) + 7) / 8;
byte[] pEnc = new byte[pLen];
Array.Copy(enc, 2, pEnc, 0, pLen);
byte[] keyEnc = new byte[enc[pLen + 2]];
Array.Copy(enc, 2 + pLen + 1, keyEnc, 0, keyEnc.Length);
ECPoint publicPoint = x9Params.Curve.DecodePoint(pEnc);
ECPrivateKeyParameters privKeyParams = (ECPrivateKeyParameters)privKey.Key;
ECPoint S = publicPoint.Multiply(privKeyParams.D).Normalize();
KeyParameter key = new KeyParameter(Rfc6637Utilities.CreateKey(privKey.PublicKeyPacket, S));
IWrapper w = PgpUtilities.CreateWrapper(ecKey.SymmetricKeyAlgorithm);
w.Init(false, key);
return(PgpPad.UnpadSessionData(w.Unwrap(keyEnc, 0, keyEnc.Length)));
}
IBufferedCipher cipher = GetKeyCipher(keyData.Algorithm);
try
{
cipher.Init(false, privKey.Key);
}
catch (InvalidKeyException e)
{
throw new PgpException("error setting asymmetric cipher", e);
}
if (keyData.Algorithm == PublicKeyAlgorithmTag.RsaEncrypt ||
keyData.Algorithm == PublicKeyAlgorithmTag.RsaGeneral)
{
byte[] bi = secKeyData[0];
cipher.ProcessBytes(bi, 2, bi.Length - 2);
}
else
{
ElGamalPrivateKeyParameters k = (ElGamalPrivateKeyParameters)privKey.Key;
int size = (k.Parameters.P.BitLength + 7) / 8;
ProcessEncodedMpi(cipher, size, secKeyData[0]);
ProcessEncodedMpi(cipher, size, secKeyData[1]);
}
try
{
return(cipher.DoFinal());
}
catch (Exception e)
{
throw new PgpException("exception decrypting secret key", e);
}
}
