How Can I detect self signed certificate from charles, wireshark etc in golang

Question

I am currently working on GO app and I wanted to know how can I detect someone using reverse proxy apps such as Charles, Wireshark and Fiddler.

I tried to read about SSL-Pinning but I couldn't find anything useful.

Answer 1

Charles and Fiddler are no reverse proxies but forward proxies. TLS interception in such proxies can be detected based on the certificate returned - it will not be the original server certificate but one created by the server. And certificate validation will fail unless the proxy is specifically trusted by importing the proxies CA certificate. SSL pinning helps too since it expects the server to use a specific certificate or a specific CA - which the SSL intercepting proxy cannot provide.

Wireshark is no kind of proxy but passive packet capturing, i.e. it makes no changes to the traffic. Because it is passive it cannot be detected from inside the client application and SSL pinning would not help either. Wireshark can not decrypt TLS traffic though by its own - it would need to have the connection specific secrets from either inside the client application or inside the server application.