eBPF TPROXY implementation

This repository demos a BPF based iptables TPROXY implementation.

Building

$ cargo build

Demo

In terminal 1, run:

$ sudo ./target/debug/proxy --addr 127.0.0.1 --port 9999

This is the proxy server. It will received the TPROXY'd packets.

In terminal 2, run:

$ sudo ./target/debug/tproxy --ifindex 1 --port 1003 --proxy-addr 127.0.0.1 --proxy-port 9999

This is the BPF based TPROXY driver. We are telling tproxy to watch ingress on ifindex 1 (usually lo) and proxy TCP packets arriving on port 1003 to the proxy which is listening with IP_TRANSPARENT on localhost:9999.

Finally, in terminal 3, run:

$ echo asdf | nc -s 127.0.0.5 127.0.0.1 1003

This sends a message via TCP to 127.0.0.1:1003.

In terminal 1 you should now see something like:

New connection:
        local: 127.0.0.1:1003
        peer: 127.0.0.5:58783