wasm-dns-https

This is a personalized experiement on Fastly Compute please do not actually use but rather enjoy the code example for now :D

How it works

Right now the code works in the following way:

1. The request is received via a HTTPS request (GET or POST) on the edge, and following RFC8484.
2. The compute code blocks domains found in the blocklist.se file and does not send the request upstream and then returns HTTP Status Code 418 because it's fun and a header that signifies "BLOCKED".
3. A domain not found in the blocklist is processed to (for now) an upstream server via HTTPS then returns to the client successfully if it exists via a forward DNS packet from the upstream Name Server (NS).

Most events are logged to a HoneyComb instance, I am especially interested in learning how to optimize this to keep resoponses low.

Analysis

So far this has been working really well, I have not switched it over to my daily driver yet but here's some examples of a test site (thanks, Can You Block It!) and it's load times:

As well a a full trace of the network requsts:

Limitations

Right now there's a couple limitations to this:

1. I have to include the entire blocklist.se file for now for a couple reasons: a. I could not find a decent API from the OISD list or anything like it, I am happy to take recommendations! b. It is too large to fit into the Fastly Config Store, which is what I was hoping to use to increase performance.
2. I am currently using the Google API as the backend/upstream Name Server, all requests are forwarded there because their JSON API is nice. a. Technically if a lot of people started using this service it would be private but since this is designed for just me it does give Google a bit of information (although the end requests are coming from Fastly's Compute Network IPs) of my requests.
3. I do not have any of their privacy perserving features but that is future work for myself.
4. Performance has not been addressed, though I am seeing decent times (thanks Rust 🦀) this is future work.

Future Work

The code is not exactly production ready, for example there's no error handling at the moment. Check in on the issues here, I plan to keep working on this until I can get it ready for use as my daily driver 😃!