protected override void HashCore(byte[] rgb, int ibStart, int cbSize)
{
IntPtr intPtr;
if (this.m_hashValue != null)
{
throw new ArgumentException("HashValue must be null.");
}
if (!HMACSHA256FISMACompliant.NativeMethods.CryptCreateHash(this.m_hProv, 32777, this.m_hKey, 0, out intPtr))
{
this.ProcessPInvokeFailure("CryptCreateHash");
}
HMACSHA256FISMACompliant.HMAC_INFO hMACINFO = new HMACSHA256FISMACompliant.HMAC_INFO()
{
HashAlgid = 32780
};
if (!HMACSHA256FISMACompliant.NativeMethods.CryptSetHashParam(intPtr, 5, hMACINFO, 0))
{
this.ProcessPInvokeFailure("CryptSetHashParam");
}
byte[] numArray = rgb;
if (ibStart > 0)
{
numArray = new byte[cbSize];
Array.Copy(rgb, ibStart, numArray, 0, cbSize);
}
if (!HMACSHA256FISMACompliant.NativeMethods.CryptHashData(intPtr, numArray, cbSize, 0))
{
this.ProcessPInvokeFailure("CryptHashData");
}
this.m_hashValue = new byte[32];
int length = (int)this.m_hashValue.Length;
if (!HMACSHA256FISMACompliant.NativeMethods.CryptGetHashParam(intPtr, 2, this.m_hashValue, ref length, 0))
{
this.ProcessPInvokeFailure("CryptGetHashParam");
}
if (!HMACSHA256FISMACompliant.NativeMethods.CryptDestroyHash(intPtr))
{
this.ProcessPInvokeFailure("CryptDestroyHash");
}
}
public static extern bool CryptSetHashParam(IntPtr hHash, uint dwParam, [In] HMACSHA256FISMACompliant.HMAC_INFO hmacInfo, uint dwFlags);
