This project consists of a DNS server written from scratch in Rust, based on RFCs 1034 and 1035. The server listens for a stream of bytes representing the DNS message on a UDP port, decodes it, looks for a resource record (RR) matching the query, and returns the encoded information back to the origin. The resource record is currently being held in records.json.
The server can be run by passing the port as an argument. You can pick any as long as it's not being used or reserved.
cargo run 1053Its functionality can be tested with a tool like dig on localhost and the specific port. In the following example, we are asking the server for the A records of the domain name example.com.
dig +retry=0 -p 1053 @127.0.0.1 +noedns example.com AA records for amazon.co.uk as stored in records.json.
Stream of bytes from the query and the response messages transmitted. As we can see, the response bytes are based on the request and there's one answer for each RR, corresponding to the ones defined in records.json.
Interpretation of the DNS message by the dig tool.
A detailed overview of the project can be found in this paper.