public static Stream PgpDecrypt(this Stream encryptedData, string armoredPrivateKey, string privateKeyPassword, Encoding armorEncoding = null)
{
var stream = PgpUtilities.GetDecoderStream(encryptedData);
var layeredStreams = new List <Stream> {
stream
}; // this is to clean up/ dispose of any layered streams.
var dataObjectFactory = new PgpObjectFactory(stream);
var dataObject = dataObjectFactory.NextPgpObject();
Dictionary <long, PgpSecretKey> secretKeys;
using (var privateKeyStream = armoredPrivateKey.Streamify(armorEncoding ?? Encoding.UTF8))
using (var decoderStream = PgpUtilities.GetDecoderStream(privateKeyStream)) {
secretKeys = new PgpSecretKeyRingBundle(decoderStream).
GetKeyRings().OfType <PgpSecretKeyRing>().
SelectMany(x => x.GetSecretKeys().OfType <PgpSecretKey>()).
ToDictionary(key => key.KeyId, value => value);
if (!secretKeys.Any())
{
throw new ArgumentException("No secret keys found.");
}
}
while (!(dataObject is PgpLiteralData) && dataObject != null)
{
try {
var compressedData = dataObject as PgpCompressedData;
var listedData = dataObject as PgpEncryptedDataList;
//strip away the compression stream
if (compressedData != null)
{
stream = compressedData.GetDataStream();
layeredStreams.Add(stream);
dataObjectFactory = new PgpObjectFactory(stream);
}
//strip the PgpEncryptedDataList
if (listedData != null)
{
var encryptedDataList =
listedData.GetEncryptedDataObjects().OfType <PgpPublicKeyEncryptedData>().First();
var decryptionKey =
secretKeys[encryptedDataList.KeyId].ExtractPrivateKey(privateKeyPassword.ToCharArray());
stream = encryptedDataList.GetDataStream(decryptionKey);
layeredStreams.Add(stream);
dataObjectFactory = new PgpObjectFactory(stream);
}
dataObject = dataObjectFactory.NextPgpObject();
} catch (Exception ex) {
//Log exception here.
throw new PgpException("Failed to strip encapsulating streams.", ex);
}
}
foreach (var layeredStream in layeredStreams)
{
layeredStream.Close();
layeredStream.Dispose();
}
if (dataObject == null)
{
return(null);
}
return((dataObject as PgpLiteralData).GetInputStream());
}
