PGP Single Pass Sign and Encrypt with Bouncy Castle

Bouncy Castle is a great open source resource. However, the off-the-shelf PGP functionality is severely lacking in real-world-usabaility. Most of what you need is easy enough to code up yourself (and I would love to contribute what I’ve done if I could). One thing that you really need that doesn’t come built-in and is actually quite hard to do right is PGP Single Pass Sign and Encrypt. Here’s a class in the style of csharp\crypto\test\src\openpgp\examples\KeyBasedFileProcessor.cs that does exactly that.

using System;
using System.IO;
using Org.BouncyCastle.Bcpg;
using Org.BouncyCastle.Bcpg.OpenPgp;
using Org.BouncyCastle.Security;

namespace PgpCrypto
{
	public class PgpProcessor
	{
		public void SignAndEncryptFile(string actualFileName, string embeddedFileName,
			Stream keyIn, long keyId, Stream outputStream,
			char[] password, bool armor, bool withIntegrityCheck, PgpPublicKey encKey)
		{
			const int BUFFER_SIZE = 1 << 16; // should always be power of 2

			if (armor)
				outputStream = new ArmoredOutputStream(outputStream);

			// Init encrypted data generator
			PgpEncryptedDataGenerator encryptedDataGenerator =
				new PgpEncryptedDataGenerator(SymmetricKeyAlgorithmTag.Cast5, withIntegrityCheck, new SecureRandom());
			encryptedDataGenerator.AddMethod(encKey);
			Stream encryptedOut = encryptedDataGenerator.Open(outputStream, new byte[BUFFER_SIZE]);

			// Init compression
			PgpCompressedDataGenerator compressedDataGenerator = new PgpCompressedDataGenerator(CompressionAlgorithmTag.Zip);
			Stream compressedOut = compressedDataGenerator.Open(encryptedOut);

			// Init signature
			PgpSecretKeyRingBundle pgpSecBundle = new PgpSecretKeyRingBundle(PgpUtilities.GetDecoderStream(keyIn));
			PgpSecretKey pgpSecKey = pgpSecBundle.GetSecretKey(keyId);
			if (pgpSecKey == null)
				throw new ArgumentException(keyId.ToString("X") + " could not be found in specified key ring bundle.", "keyId");
			PgpPrivateKey pgpPrivKey = pgpSecKey.ExtractPrivateKey(password);
			PgpSignatureGenerator signatureGenerator = new PgpSignatureGenerator(pgpSecKey.PublicKey.Algorithm, HashAlgorithmTag.Sha1);
			signatureGenerator.InitSign(PgpSignature.BinaryDocument, pgpPrivKey);
			foreach (string userId in pgpSecKey.PublicKey.GetUserIds())
			{
				PgpSignatureSubpacketGenerator spGen = new PgpSignatureSubpacketGenerator();
				spGen.SetSignerUserId(false, userId);
				signatureGenerator.SetHashedSubpackets(spGen.Generate());
				// Just the first one!
				break;
			}
			signatureGenerator.GenerateOnePassVersion(false).Encode(compressedOut);

			// Create the Literal Data generator output stream
			PgpLiteralDataGenerator literalDataGenerator = new PgpLiteralDataGenerator();
			FileInfo embeddedFile = new FileInfo(embeddedFileName);
			FileInfo actualFile = new FileInfo(actualFileName);
			// TODO: Use lastwritetime from source file
			Stream literalOut = literalDataGenerator.Open(compressedOut, PgpLiteralData.Binary,
				embeddedFile.Name, actualFile.LastWriteTime, new byte[BUFFER_SIZE]);

			// Open the input file
			FileStream inputStream = actualFile.OpenRead();

			byte[] buf = new byte[BUFFER_SIZE];
			int len;
			while ((len = inputStream.Read(buf, 0, buf.Length)) > 0)
			{
				literalOut.Write(buf, 0, len);
				signatureGenerator.Update(buf, 0, len);
			}

			literalOut.Close();
			literalDataGenerator.Close();
			signatureGenerator.Generate().Encode(compressedOut);
			compressedOut.Close();
			compressedDataGenerator.Close();
			encryptedOut.Close();
			encryptedDataGenerator.Close();
			inputStream.Close();

			if (armor)
				outputStream.Close();
		}
	}
}

TortoiseSVN: Tweaking the Context Menu; Global Ignore

If you use TortoiseSVN alot like I do, then you’ve probably often wished you could put more frequently used items in the first context menu that comes up when you right click on a file in Windows Explorer. By default only update, commit, and checkout are there. You can choose which items appear in the first menu and which appear in the TortoiseSVN sub-menu by selecting Settings, Look and Feel. There you can check and uncheck items to determine whether or not they are on the sub-menu. I got rid of Checkout and included add, delete, rename, and diff.

Another time saver available in settings is Global Ignore Pattern. Items matching this pattern will automatically be ignored when you commit. I currently have mine set to:

*/[Bb]in [Bb]in */obj obj */[Rr]elease *.user *.suo *.resharper */_ReSharper.* _ReSharper.* *.bak *.dll *.pdb.