Source code for the Network Benchmark Utility

Where can I download the source code for the Network Benchmark Utility used in the session "Port your Mac app to Apple Silicon?" I want to look at the sources for the TLSPlugin it uses.
The source code for the NetworkBenchmarking app is not available publicly. You can find more documentation on plug-ins on Apple Silicon Macs at Porting Your macOS Apps to Apple Silicon documentation page, and feel free to ask any specific questions about plug-ins here in the Developer Forums.
Source code for the Network Benchmark Utility
 
 
Q