Blind RSA signature using .NET cryptography API?
.net, blind-signature, cryptography, encryption, rsa
Solution
You are going to have to roll you own. You can use the BigInteger class of .NET 4 or just use the Bouncycastle C# library.
Problem
I'd like to implement a blind RSA signature in .NET. Is there any way to use the standard `System.Security.Cryptography` APIs to achieve this? The "obvious" idea doesn't work: ``` using (var rsa = new RSACryptoServiceProvider()) signed = rsa.Decrypt(messageBytes, false); // CryptographicException: bad data ``` I appreciate the dangers of blind signature but let's ignore those for a moment. Also, I'm not interested in other types of digital signatures.