How to Create an HTTPS Proxy Like Burp Suite

A proxy server is a server application that acts as an intermediary between a client requesting a resource and the server providing that resource, improving privacy, security, and possibly performance. In simpler terms, a proxy intercepts traffic between a client and another server. HTTP is the foundation of data communication for the web, and HTTPS is a secure version of HTTP that uses SSL/TLS encryption. When working with HTTPS traffic, proxies need to be able to decrypt the data, which is achieved through the CONNECT method of HTTP. To build a basic HTTPS proxy, you need an HTTP parser and an SSL handler, and the proxy must handle the CONNECT method. Dealing with SSL certificates is a major challenge in building an HTTPS proxy, requiring the creation of a CA root certificate and adding it to the browser's trust store. The proxy can then generate and sign domain-specific certificates using the trusted CA root certificate. The proxy workflow involves intercepting the CONNECT request, checking for a certificate, and establishing an SSL connection with the target server. A simple HTTPS proxy written in C is available on GitHub, providing a starting point for understanding and creating your own HTTPS proxy. With the right components in place, you can intercept and analyze web traffic, ensuring flexibility and security in your network interactions. By creating an HTTPS proxy, you can achieve similar functionality to tools like Burp Suite.