public static void BeginStreamFromFile(string filename, out IntPtr vFPtr)
{
vFPtr = IntPtr.Zero;
unsafe
{
void *vorbisFile = null;
NativeMethods.ErrorCode err = (NativeMethods.ErrorCode)NativeMethods.init_for_ogg_decode(filename, &vorbisFile);
if (err != NativeMethods.ErrorCode.None)
{
throw new ApplicationException(
String.Format("An OggVorbis error occurred: {0}", err));
}
vFPtr = (IntPtr)vorbisFile;
}
}
public static void BeginStreamFromMemory(byte[] memory, out IntPtr vFPtr)
{
vFPtr = IntPtr.Zero;
unsafe
{
void *vorbisFile = null;
NativeMethods.ErrorCode err = (NativeMethods.ErrorCode)NativeMethods.memory_stream_for_ogg_decode(memory, memory.Length, &vorbisFile);
if (err != NativeMethods.ErrorCode.None)
{
throw new ApplicationException(
String.Format("An OggVorbis error occurred: {0}", err));
}
vFPtr = (IntPtr)vorbisFile;
}
}
public static byte[] DeriveKeyMaterial(
this ECDiffieHellmanCng provider,
ECDiffieHellmanPublicKey otherPartyPublicKey,
byte[] algorithmId,
byte[] partyUInfo,
byte[] partyVInfo)
{
Collection <IntPtr> ResourcesToFree = new Collection <IntPtr>();
try
{
using SafeNCryptSecretHandle Agreement = provider.DeriveSecretAgreementHandle(otherPartyPublicKey);
IntPtr AlgorithmIdPtr = Marshal.AllocHGlobal(algorithmId.Length);
ResourcesToFree.Add(AlgorithmIdPtr);
Marshal.Copy(algorithmId, 0, AlgorithmIdPtr, algorithmId.Length);
IntPtr PartyUPtr = Marshal.AllocHGlobal(partyUInfo.Length);
ResourcesToFree.Add(PartyUPtr);
Marshal.Copy(partyUInfo, 0, PartyUPtr, partyUInfo.Length);
IntPtr PartyVPtr = Marshal.AllocHGlobal(partyVInfo.Length);
ResourcesToFree.Add(PartyVPtr);
Marshal.Copy(partyVInfo, 0, PartyVPtr, partyVInfo.Length);
NativeMethods.NCryptBuffer[] Buffers = new NativeMethods.NCryptBuffer[]
{
new NativeMethods.NCryptBuffer
{
cbBuffer = (uint)algorithmId.Length,
BufferType = NativeMethods.BufferType.KDF_ALGORITHMID,
pvBuffer = AlgorithmIdPtr
},
new NativeMethods.NCryptBuffer
{
cbBuffer = (uint)partyUInfo.Length,
BufferType = NativeMethods.BufferType.KDF_PARTYUINFO,
pvBuffer = PartyUPtr
},
new NativeMethods.NCryptBuffer
{
cbBuffer = (uint)partyVInfo.Length,
BufferType = NativeMethods.BufferType.KDF_PARTYVINFO,
pvBuffer = PartyVPtr
}
};
IntPtr BufferPtr = Marshal.AllocHGlobal(Buffers.Length * Marshal.SizeOf(typeof(NativeMethods.NCryptBuffer)));
ResourcesToFree.Add(BufferPtr);
IntPtr Location = BufferPtr;
for (int i = 0; i < Buffers.Length; i++)
{
Marshal.StructureToPtr(Buffers[i], Location, false);
Location = new IntPtr(Location.ToInt64() + Marshal.SizeOf(typeof(NativeMethods.NCryptBuffer)));
}
NativeMethods.NCryptBufferDesc ParameterList = new NativeMethods.NCryptBufferDesc
{
cBuffers = Buffers.Length,
pBuffers = BufferPtr
};
byte[] DerivedKey = new byte[32];
NativeMethods.ErrorCode ErrorCode = NativeMethods.NCryptDeriveKey(
Agreement,
"SP800_56A_CONCAT",
ref ParameterList,
DerivedKey,
DerivedKey.Length,
out int NumberOfBytesDerived,
0);
if (ErrorCode != NativeMethods.ErrorCode.Success)
{
throw new InvalidOperationException($"KeyMaterial could not be derived. ErrorCode [{ErrorCode}], Win32Error [{Marshal.GetLastWin32Error()}] returned.");
}
if (NumberOfBytesDerived != 32)
{
throw new InvalidOperationException("KeyMaterial size was invalid.");
}
return(DerivedKey);
}
finally
{
foreach (IntPtr Resource in ResourcesToFree)
{
Marshal.FreeHGlobal(Resource);
}
}
}
