DSVPN

DSVPN is a Dead Simple VPN, designed to address the most common use case for using a VPN. Runs on TCP. Works pretty much everywhere, including on public WiFi where only TCP/443 is open or reliable. Uses only modern cryptography, with formally verified implementations. Small and constant memory footprint. Doesn't perform any heap memory allocations. Small (~25 KB), with an equally small and readable code base. No external dependencies. Works out of the box. No lousy documentation to read. No configuration file. No post-configuration. Run a single-line command on the server, a similar one on the client and you're done. No firewall and routing rules to manually mess with. Doesn't leak between reconnects if the network doesn't change. Blocks IPv6 on the client to prevent IPv6 leaks. Works on Linux (kernel >= 3.17), macOS and OpenBSD, as well as DragonFly BSD, FreeBSD and NetBSD in client and point-to-point modes. Adding support for other operating systems is trivial.