ExportPkcs8KeyBlob() [1/2]

static unsafe bool System.Security.Cryptography.CngKeyLite.ExportPkcs8KeyBlob ( bool allocate, SafeNCryptKeyHandle keyHandle, ReadOnlySpan< char > password, int kdfCount, Span< byte > destination, out int bytesWritten, out byte[] allocated )

inlinestaticpackage

Definition at line 99 of file CngKeyLite.cs.

    {
        using SafeUnicodeStringHandle safeUnicodeStringHandle = new SafeUnicodeStringHandle(password);
        fixed (byte* ptr2 = s_pkcs12TripleDesOidBytes)
        {
            global::Interop.NCrypt.NCryptBuffer* ptr = stackalloc global::Interop.NCrypt.NCryptBuffer[3];
            global::Interop.NCrypt.PBE_PARAMS pBE_PARAMS = default(global::Interop.NCrypt.PBE_PARAMS);
            Span<byte> data = new Span<byte>(pBE_PARAMS.rgbSalt, 8);
            RandomNumberGenerator.Fill(data);
            pBE_PARAMS.Params.cbSalt = data.Length;
            pBE_PARAMS.Params.iIterations = kdfCount;
            *ptr = new global::Interop.NCrypt.NCryptBuffer
            {
                BufferType = global::Interop.NCrypt.BufferType.PkcsSecret,
                cbBuffer = checked(2 * (password.Length + 1)),
                pvBuffer = safeUnicodeStringHandle.DangerousGetHandle()
            };
            if (ptr->pvBuffer == IntPtr.Zero)
            {
                ptr->cbBuffer = 0;
            }
            ptr[1] = new global::Interop.NCrypt.NCryptBuffer
            {
                BufferType = global::Interop.NCrypt.BufferType.PkcsAlgOid,
                cbBuffer = s_pkcs12TripleDesOidBytes.Length,
                pvBuffer = (IntPtr)ptr2
            };
            ptr[2] = new global::Interop.NCrypt.NCryptBuffer
            {
                BufferType = global::Interop.NCrypt.BufferType.PkcsAlgParam,
                cbBuffer = sizeof(global::Interop.NCrypt.PBE_PARAMS),
                pvBuffer = (IntPtr)(&pBE_PARAMS)
            };
            global::Interop.NCrypt.NCryptBufferDesc nCryptBufferDesc = default(global::Interop.NCrypt.NCryptBufferDesc);
            nCryptBufferDesc.cBuffers = 3;
            nCryptBufferDesc.pBuffers = (IntPtr)ptr;
            nCryptBufferDesc.ulVersion = 0;
            global::Interop.NCrypt.NCryptBufferDesc pParameterList = nCryptBufferDesc;
            global::Interop.NCrypt.ErrorCode errorCode = global::Interop.NCrypt.NCryptExportKey(keyHandle, IntPtr.Zero, "PKCS8_PRIVATEKEY", ref pParameterList, ref MemoryMarshal.GetReference(default(Span<byte>)), 0, out var pcbResult, 0);
            if (errorCode != 0)
            {
                throw errorCode.ToCryptographicException();
            }
            allocated = null;
            if (allocate)
            {
                allocated = new byte[pcbResult];
                destination = allocated;
            }
            else if (pcbResult > destination.Length)
            {
                bytesWritten = 0;
                return false;
            }
            errorCode = global::Interop.NCrypt.NCryptExportKey(keyHandle, IntPtr.Zero, "PKCS8_PRIVATEKEY", ref pParameterList, ref MemoryMarshal.GetReference(destination), destination.Length, out pcbResult, 0);
            if (errorCode != 0)
            {
                throw errorCode.ToCryptographicException();
            }
            if (allocate && pcbResult != destination.Length)
            {
                byte[] array = new byte[pcbResult];
                destination.Slice(0, pcbResult).CopyTo(array);
                CryptographicOperations.ZeroMemory(allocated.AsSpan(0, pcbResult));
                allocated = array;
            }
            bytesWritten = pcbResult;
            return true;
        }
    }

References System.array, System.destination, System.Security.Cryptography.RandomNumberGenerator.Fill(), System.ReadOnlySpan< T >.Length, System.Span< T >.Length, System.Security.Cryptography.CngKeyLite.s_pkcs12TripleDesOidBytes, System.IntPtr.Zero, and System.Security.Cryptography.CryptographicOperations.ZeroMemory().