// Licensed to the .NET Foundation under one or more agreements.
// The .NET Foundation licenses this file to you under the MIT license.
 
using System;
 
namespace Microsoft.AspNetCore.Cryptography.Cng;
 
/// <summary>
/// Wraps utility BCRYPT APIs that don't work directly with handles.
/// </summary>
internal static unsafe class BCryptUtil
{
    /// <summary>
    /// Fills a buffer with cryptographically secure random data.
    /// </summary>
    public static void GenRandom(byte* pbBuffer, uint cbBuffer)
    {
        if (cbBuffer != 0)
        {
            int ntstatus = UnsafeNativeMethods.BCryptGenRandom(
                hAlgorithm: IntPtr.Zero,
                pbBuffer: pbBuffer,
                cbBuffer: cbBuffer,
                dwFlags: BCryptGenRandomFlags.BCRYPT_USE_SYSTEM_PREFERRED_RNG);
            UnsafeNativeMethods.ThrowExceptionForBCryptStatus(ntstatus);
        }
    }
}