/// <summary>
/// Extract a <c>PgpPrivateKey</c> from this secret key's encrypted contents.
/// </summary>
/// <param name="passPhrase"></param>
/// <returns></returns>
/// <exception cref="PgpException">
/// unknown public key algorithm encountered
/// or
/// Exception constructing key
/// </exception>
public IPgpPrivateKey ExtractPrivateKey(char[] passPhrase)
{
var secKeyData = _secret.GetSecretKeyData();
if (secKeyData == null || secKeyData.Length < 1)
{
return(null);
}
var pubPk = _secret.PublicKeyPacket;
try
{
var data = ExtractKeyData(passPhrase);
using (var memory = new MemoryStream(data, false))
{
using (var bcpgIn = BcpgInputStream.Wrap(memory))
{
IAsymmetricKeyParameter privateKey;
switch (pubPk.Algorithm)
{
case PublicKeyAlgorithmTag.RsaEncrypt:
case PublicKeyAlgorithmTag.RsaGeneral:
case PublicKeyAlgorithmTag.RsaSign:
var rsaPub = (RsaPublicBcpgKey)pubPk.Key;
var rsaPriv = new RsaSecretBcpgKey(bcpgIn);
var rsaPrivSpec = new RsaPrivateCrtKeyParameters(
rsaPriv.Modulus,
rsaPub.PublicExponent,
rsaPriv.PrivateExponent,
rsaPriv.PrimeP,
rsaPriv.PrimeQ,
rsaPriv.PrimeExponentP,
rsaPriv.PrimeExponentQ,
rsaPriv.CrtCoefficient);
privateKey = rsaPrivSpec;
break;
case PublicKeyAlgorithmTag.Dsa:
var dsaPub = (DsaPublicBcpgKey)pubPk.Key;
var dsaPriv = new DsaSecretBcpgKey(bcpgIn);
var dsaParams = new DsaParameters(dsaPub.P, dsaPub.Q, dsaPub.G);
privateKey = new DsaPrivateKeyParameters(dsaPriv.X, dsaParams);
break;
case PublicKeyAlgorithmTag.ElGamalEncrypt:
case PublicKeyAlgorithmTag.ElGamalGeneral:
var elPub = (ElGamalPublicBcpgKey)pubPk.Key;
var elPriv = new ElGamalSecretBcpgKey(bcpgIn);
var elParams = new ElGamalParameters(elPub.P, elPub.G);
privateKey = new ElGamalPrivateKeyParameters(elPriv.X, elParams);
break;
case PublicKeyAlgorithmTag.Ecdh:
var ecdhPub = (ECDHPublicBcpgKey)pubPk.Key;
var ecdhPriv = new ECSecretBcpgKey(bcpgIn);
privateKey = new ECDHPrivateKeyParameters(ecdhPriv.X,
new ECDHPublicKeyParameters(ecdhPub.Point, ecdhPub.Oid, ecdhPub.HashAlgorithm, ecdhPub.SymmetricKeyAlgorithm),
PgpPublicKey.BuildFingerprint(pubPk));
break;
case PublicKeyAlgorithmTag.Ecdsa:
var ecdsaPub = (ECPublicBcpgKey)pubPk.Key;
var ecdsaPriv = new ECSecretBcpgKey(bcpgIn);
privateKey = new ECPrivateKeyParameters(pubPk.Algorithm.ToString(), ecdsaPriv.X, ecdsaPub.Oid);
break;
default:
throw new PgpException("unknown public key algorithm encountered");
}
return(new PgpPrivateKey(privateKey, KeyId));
}
}
}
catch (PgpException)
{
throw;
}
catch (Exception e)
{
throw new PgpException("Exception constructing key", e);
}
}