internal static extern uint NCryptVerifySignature(SafeNCryptKeyHandle hKey,
ref BCrypt.BCRYPT_PSS_PADDING_INFO pPaddingInfo,
byte[] pbHashValue,
int cbHashValue,
byte[] pbSignature,
int cbSignature,
uint dwFlags);
internal static extern uint NCryptSignHash(SafeNCryptKeyHandle hKey,
ref BCrypt.BCRYPT_PSS_PADDING_INFO pPaddingInfo,
byte[] pbHashValue,
int cbHashValue,
byte[] pbSignature,
int cbSignature,
out uint pcbResult,
uint dwFlags);
private static bool VerifyHash(byte[] hash, byte[] signature, CngKey key, string algorithm, int saltSize)
{
var paddingInfo = new BCrypt.BCRYPT_PSS_PADDING_INFO(algorithm, saltSize);
uint status = NCrypt.NCryptVerifySignature(key.Handle, ref paddingInfo, hash, hash.Length, signature, signature.Length, BCrypt.BCRYPT_PAD_PSS);
if (status == NCrypt.NTE_BAD_SIGNATURE) //honestly it always failing with NTE_INVALID_PARAMETER, but let's stick to public API
return false;
if (status != BCrypt.ERROR_SUCCESS)
throw new CryptographicException(string.Format("NCrypt.NCryptSignHash() (signature size) failed with status code:{0}", status));
return true;
}
private static byte[] SignHash(byte[] hash, CngKey key, string algorithm, int saltSize)
{
var paddingIndo=new BCrypt.BCRYPT_PSS_PADDING_INFO(algorithm, saltSize);
uint size;
uint status;
status = NCrypt.NCryptSignHash(key.Handle, ref paddingIndo, hash, hash.Length, null, 0, out size,BCrypt.BCRYPT_PAD_PSS);
if (status != BCrypt.ERROR_SUCCESS)
throw new CryptographicException(string.Format("NCrypt.NCryptSignHash() (signature size) failed with status code:{0}", status));
byte[] signature=new byte[size];
status = NCrypt.NCryptSignHash(key.Handle, ref paddingIndo, hash, hash.Length, signature, signature.Length, out size, BCrypt.BCRYPT_PAD_PSS);
if (status != BCrypt.ERROR_SUCCESS)
throw new CryptographicException(string.Format("NCrypt.NCryptSignHash() failed with status code:{0}", status));
return signature;
}