saminiir/level-ip

A hacker's userspace TCP/IP stack

3,137

575 commits

updated Dec 13, 2022

www.saminiir.com

See the code

README

Level-IP

Level-IP is a Linux userspace TCP/IP stack, implemented with TUN/TAP devices.

The main goals are to:

Learn TCP/IP
Learn Linux systems/network programming
Learn Linux Socket API

The results of the learning experience will be accompanied by explanatory blog posts:

Part 1, Ethernet & ARP: http://www.saminiir.com/lets-code-tcp-ip-stack-1-ethernet-arp
Part 2, IPv4 & ICMPv4: http://www.saminiir.com/lets-code-tcp-ip-stack-2-ipv4-icmpv4
Part 3, TCP Basics & Handshake: http://www.saminiir.com/lets-code-tcp-ip-stack-3-tcp-handshake/
Part 4, TCP Data Flow & Socket API: http://www.saminiir.com/lets-code-tcp-ip-stack-4-tcp-data-flow-socket-api/
Part 5, TCP Retransmission: http://www.saminiir.com/lets-code-tcp-ip-stack-5-tcp-retransmission/

See Getting Started.

For development documentation, start with Development.

Reference works

Linux kernel TCP/IP stack, source code
picoTCP, source code
Xiaochen Wang's TCP/IP stack, source code

License

See LICENSE.md (MIT)

socket-api

tcp

tcp-ip

tuntap

userspace-networking

Significant stargazers

(top 24 of 38)

Julian Berman

447 followers · starred Mar 2025

zhenghaoz

288 followers · starred Sep 2020

Pekka Enberg

2,031 followers · starred Mar 2016

Eric Curtin

387 followers · starred Dec 2020

Similar repos

pandax381/microps

An implementation of a small TCP/IP protocol stack for learning.

1,323

chenshuo/4.4BSD-Lite2

User-mode TCP/IP stack from 4.4BSD-Lite2, a companion of TCP/IP Illustrated vol. 2

377

TanayK07/networking-from-scratch

Build the network stack from raw bytes. 289 hands-on lessons in C and Python — from Ethernet frames…

cozis/microtcp

A minimal TCP/IP stack

544

adamdunkels/uip

The historical uIP sources

1,089

google/netstack

IPv4 and IPv6 userland network stack

3,114

tass-belgium/picotcp

PicoTCP is a free TCP/IP stack implementation

1,311

Ghvstcode/Rust-Tcp

Implementing TCP In Rust

465