Open Source C# Reverse Proxy Servers

FastTunnel is a high-performance cross-platform intranet penetration tool. With it, you can expose intranet services to the public network for yourself or anyone to access. Unlike other penetration tools, the FastTunnel project is committed to creating an easy-to-extensible and easy-to-maintain intranet penetration framework. You can build your own penetration application by referencing the nuget package of FastTunnel.Core, and target the business extension functions you need.

YARP is a library to help create reverse proxy servers that are high-performance, production-ready, and highly customizable. We found a bunch of internal teams at Microsoft who were either building a reverse proxy for their service or had been asking about APIs and tech for building one, so we decided to get them all together to work on a common solution, this project. Each of these projects was doing something slightly off the beaten path which meant they were not well served by existing proxies, and customization of those proxies had a high cost and ongoing maintenance considerations. Many of the existing proxies were built to support HTTP/1.1, but with workloads changing to include gRPC traffic, they require HTTP/2 support which requires a significantly more complex implementation. By using YARP the projects get to customize the routing and handling behavior without having to implement the http protocol.

A toolkit to create code-first HTTP Reverse Proxies hosted in ASP.NET Core as middleware. This allows focused code-first proxies that can be embedded in existing ASP.NET Core applications or deployed as a standalone server. Deployable anywhere ASP.NET Core is deployable such as Windows, Linux, Containers and Serverless (with caveats). Having built proxies many times before, I felt it is time to make a package. Forked from ASP.NET labs, it has been heavily modified with a different API, to facilitate a wider variety of proxying scenarios (i.e. routing based on a JWT claim) and interception of the proxy requests/responses for customization of headers and (optionally) request/response bodies. It also uses HttpClientFactory internally that will mitigate against DNS caching issues making it suitable for microservice/container environments.