RSA CryptoAPI keyblob decoder utility

From: Michel Gallant (
Date: 09/12/03

Date: Fri, 12 Sep 2003 12:56:29 -0400

Here is a .NET C# utility RSAKeyblob which reads and parses
certain types of CryptoAPI keyblob files, typically exported using
The console utility displays the key type, RSA public exponent and
RSA modulus (big-endian order). For unencrypted PRIVATEKEYBLOB
(including sn.exe generated keypairs), also displays private key parameters.

The RSK key parameters are decoded in a form usable for initialization of
RSAParameters and RSACryptoServiceProvider.

 - Michel Gallant
    MVP Security