Icmptunnel-rs

A rust implementation of an icmp tunnel, complete with authentication and encryption. Inspired by https://github.com/DhavalKapil/icmptunnel

Quickstart

git clone https://github.com/fabi321/icmptunnel-rs.git
cd icmptunnel-rs
cargo build --release

running the server

sudo ./target/release/icmptunnel-rs server --password <password>

running the client

sudo ./target/release/icmptunnel-rs client --password <password> --server-address <server ip>

Features

• Authentication
• Transparent server (if packet is not a tunnel packet, will reply with normal icmp echo reply)
• Encryption
• Automatic IP allocation for connecting clients (up to 253 clients per server)
• Session handling with timeouts
• Session key renewal

Known limitations

• MTU of transfer medium is hardcoded (no support if MTU between server and client are below hardcoded MTU)
• IPv4 only, both for transmitted packets and encapsulating ICMP packets
• Only tested on linux

Known security issues

• Passwords are exposed as they are visible in process list
• It is possible to reuse the hashed password. However, sessions created this way are effectively useless as the attacker would need the private dh-key in order to actually use it
• Timing side channels allow for server discovery (at least in theory)