/// <summary>
/// Reset the hash algorithm to begin hashing a new set of data
/// </summary>
public SafeCapiHashHandle Initialize()
{
Contract.Ensures(m_hashHandle != null && !m_hashHandle.IsInvalid && !m_hashHandle.IsClosed);
Contract.Assert(m_cspHandle != null);
// Try to create a new hash algorithm to use
SafeCapiHashHandle?newHashAlgorithm = null;
#if !NET_COREAPP_50
RuntimeHelpers.PrepareConstrainedRegions();
#endif
try
{
if (!CapiNative.UnsafeNativeMethods.CryptCreateHash(m_cspHandle,
m_algorithmId,
SafeCapiKeyHandle.InvalidHandle,
0,
out newHashAlgorithm))
{
// BadAlgorithmId means that this CSP does not support the specified algorithm, which means
// that we're on a platform that does not support the given hash function.
int error = Marshal.GetLastWin32Error();
if (error == (int)CapiNative.ErrorCode.BadAlgorithmId)
{
throw new PlatformNotSupportedException(SR.Cryptography_PlatformNotSupported);
}
else
{
throw new CryptographicException(error);
}
}
}
finally
{
if (newHashAlgorithm != null && !newHashAlgorithm.IsInvalid)
{
newHashAlgorithm.SetParentCsp(m_cspHandle);
}
}
// If we created a new algorithm, dispose of the old one and use the new one
Contract.Assert(newHashAlgorithm != null, "newHashAlgorithm != null");
if (m_hashHandle != null)
{
m_hashHandle.Dispose();
}
m_hashHandle = newHashAlgorithm;
return(m_hashHandle);
}
public void Dispose()
{
m_hashHandle?.Dispose();
m_cspHandle?.Dispose();
}