Spartan

Spartan is an ultra-lightweight FASM TCP server that utilises pure Linux syscalls.

Key Features

• ~1 kb static binary
• Nagle-disabled packet transmission
• Complete error handling and logging via the standard streams

Usage

To test Spartan, simply run the binary, and then establish a connection to localhost:1337 using any preferred method. E.g., with netcat:

Process 1 (Server)

./spartan

Process 2 (Client)

nc localhost 1337

The server will respond with a small HTTP packet. Since the socket has TCP_NODELAY enabled and responses aren't buffered, connecting via a browser will likely trigger multiple responses due to additional resource requests (e.g., a favicon).

Build Locally

Prerequisites

• x64 Linux
• FASM
• Make
• readelf (optional)
• GDB (optional)
• strace (optional)
• GCC (optional)

Makefile Targets

• Build the executable:

make

• Run the server:

make run

• Debug with the GDB TUI:

make header
make debug ENTRY=<entry point address from the ELF header>

• Monitor system calls:

make strace

• Find relevant syscall option values:

make constants

Future Plans

• Add a graceful shutdown mechanism
• Add command-line configuration options
• Experiment with multithreading