/// <summary>
/// Hash public key info of a specified RSA key
/// </summary>
/// <param name="key"></param>
/// <returns></returns>
private byte[] HashPublicKeyInfo(RSACryptoServiceProvider key)
{
CryptoApiMethods.SafeCryptProviderHandle hProv = new CryptoApiMethods.SafeCryptProviderHandle();
IntPtr publicKeyInfoPtr = IntPtr.Zero;
byte[] ret = null;
uint len = 0;
try
{
publicKeyInfoPtr = ExportPublicKeyInfo(key);
CryptoApiMethods.CERT_PUBLIC_KEY_INFO publicKeyInfo = (CryptoApiMethods.CERT_PUBLIC_KEY_INFO)Marshal.PtrToStructure(publicKeyInfoPtr, typeof(CryptoApiMethods.CERT_PUBLIC_KEY_INFO));
hProv = OpenRSAProvider(key.CspKeyContainerInfo.ProviderName, key.CspKeyContainerInfo.KeyContainerName);
if (!CryptoApiMethods.CryptHashPublicKeyInfo(hProv, 0, 0, CryptoApiMethods.CertEncoding.X509_ASN_ENCODING,
publicKeyInfo, null, out len))
{
throw new Win32Exception(Marshal.GetLastWin32Error());
}
ret = new byte[len];
if (!CryptoApiMethods.CryptHashPublicKeyInfo(hProv, 0, 0, CryptoApiMethods.CertEncoding.X509_ASN_ENCODING,
publicKeyInfo, ret, out len))
{
throw new Win32Exception(Marshal.GetLastWin32Error());
}
}
finally
{
if (!hProv.IsInvalid)
{
hProv.Close();
}
if (publicKeyInfoPtr != IntPtr.Zero)
{
Marshal.FreeHGlobal(publicKeyInfoPtr);
}
}
return(ret);
}
