/// <summary>
/// Retrieves a SignalServiceAttachment
/// </summary>
/// <param name="token"></param>
/// <param name="pointer">The <see cref="SignalServiceAttachmentPointer"/>
/// received in a <see cref="SignalServiceDataMessage"/></param>
/// <param name="tmpCipherDestination">The temporary destination for this attachment before decryption</param>
/// <param name="maxSizeBytes">The maximum size for this attachment (not yet implemented)</param>
/// <param name="listener">An optional listener (may be null) to receive callbacks on download progress.</param>
public async Task <Stream> RetrieveAttachment(CancellationToken token, SignalServiceAttachmentPointer pointer, Stream tmpCipherDestination, int maxSizeBytes, IProgressListener listener)
{
await Socket.RetrieveAttachment(token, pointer.Id, tmpCipherDestination, maxSizeBytes);
tmpCipherDestination.Position = 0;
return(AttachmentCipherInputStream.CreateFor(tmpCipherDestination, pointer.Size != null ? pointer.Size.Value : 0, pointer.Key, pointer.Digest));
}
private void DecryptAttachment(SignalServiceAttachmentPointer pointer, Stream ciphertextFileStream, Stream plaintextFileStream)
{
byte[] buf = new byte[32];
Stream s = AttachmentCipherInputStream.CreateFor(ciphertextFileStream, pointer.Size != null ? pointer.Size.Value : 0, pointer.Key, pointer.Digest);
s.CopyTo(plaintextFileStream);
}