private void OnMachineAuth(SteamUser.UpdateMachineAuthCallback callback) { // Write sentry hash int fileSize; byte[] sentryHash; using (var file = File.Open("sentryhash", FileMode.OpenOrCreate, FileAccess.ReadWrite)) { file.Seek(callback.Offset, SeekOrigin.Begin); file.Write(callback.Data, 0, callback.BytesToWrite); fileSize = (int)file.Length; file.Seek(0, SeekOrigin.Begin); using (var hash = new SHA1CryptoServiceProvider()) sentryHash = hash.ComputeHash(file); } // Tell Steam we're accepting the sentry file kraxbot.SendMachineAuthResponse(new SteamUser.MachineAuthDetails { JobID = callback.JobID, FileName = callback.FileName, BytesWritten = callback.BytesToWrite, FileSize = fileSize, Offset = callback.Offset, Result = EResult.OK, LastError = 0, OneTimePassword = callback.OneTimePassword, SentryFileHash = sentryHash }); }