Nice, I am finally able to launch the My PacketTunnelProvider code, however I am seeing this error in my console, not sure what it means:
Sandbox: com.test.vpn.d(65504) deny(1) mach-lookup com.apple.AppSSO.service-xpc
Violation: deny(1) mach-lookup com.apple.AppSSO.service-xpc
Process: com.test.vpn.d [65504]
Path: /Library/SystemExtensions/2EA7CA6C-4185-4D33-A43B-8ACAE5C4BFFA/com.test.vpn.NetworkExtension.systemextension/Contents/MacOS/com.test.vpn.NetworkExtension
Load Address: 0x101e01000
Identifier: com.test.vpn.NetworkExtension
Version: 1 (1.0)
Code Type: x86_64 (Native)
Parent Process: launchd [1]
Responsible: /Library/SystemExtensions/2EA7CA6C-4185-4D33-A43B-8ACAE5C4BFFA/com.test.vpn.NetworkExtension.systemextension/Contents/MacOS/com.test.vpn.NetworkExtension
User ID: 0
Date/Time: 2022-03-25 16:48:03.273 PDT
OS Version: macOS 12.3 (21E230)
Release Type: User
Report Version: 8
MetaData: {"target":"com.apple.AppSSO.service-xpc","responsible-process-signing-id":"com.test.vpn.NetworkExtension","policy-description":"Sandbox","mach_namespace":1,"responsible-process-team-id":"QEXH8ZM8AV","normalized_target":["com.apple.AppSSO.service-xpc"],"profile-flags":0,"errno":1,"platform-policy":false,"primary-filter":"global-name","global-name":"com.apple.AppSSO.service-xpc","operation":"mach-lookup","platform-binary":false,"process-path":"\/Library\/SystemExtensions\/2EA7CA6C-4185-4D33-A43B-8ACAE5C4BFFA\/com.test.vpn.NetworkExtension.systemextension\/Contents\/MacOS\/com.test.vpn.NetworkExtension","platform_binary":"no","primary-filter-value":"com.apple.AppSSO.service-xpc","container":"\/private\/var\/root\/Library\/Containers\/com.test.vpn.NetworkExtension\/Data","hardware":"Mac","checker":"launchd","profile-in-collection":false,"sandbox_checker":"launchd","build":"macOS 12.3 (21E230)","action":"deny","summary":"deny(1) mach-lookup com.apple.AppSSO.service-xpc","checker-pid":1,"pid":65504,"process":"com.test.vpn.d","flags":5,"signing-id":"com.test.vpn.NetworkExtension","binary-in-trust-cache":false,"team-id":"QEXH8ZM8AV","responsible-process-path":"\/Library\/SystemExtensions\/2EA7CA6C-4185-4D33-A43B-8ACAE5C4BFFA\/com.test.vpn.NetworkExtension.systemextension\/Contents\/MacOS\/com.test.vpn.NetworkExtension","apple-internal":false,"uid":0,"release-type":"User"}