A GNU implementation of the Secure Shell protocols

lsh is a free implementation (in the GNU sense) of the ssh version 2 protocol, currently being standardised by the IETF SECSH working group.

This page should help you find any lsh related resources you need.


The lsh source distribution comes with a texinfo manual. You can also read the manual online. If you're interested in hacking lsh, make sure to read the README and doc/HACKING files in the distribution.


The CVS server for lsh is located at cvs.lysator.liu.se. Both anonymous pserver access (cvs -d :pserver:anonymous@cvs.lysator.liu.se co lsh) and a cvsweb interface is available.

There's also an mailing list you might want to subscribe to.


lsh uses linux-style version numbers, i.e. 1.2.x, 1.4.x etc are intended to be stable, while 1.1.x, 1.3.x, 1.5.x etc are development versions.

lsh releases are signed using GNU Privacy Guard, with this public key (HTTP from Sweden, or FTP from Sweden)

You can get the latest lsh releases from

There are also some mirror sites:

Related links

A Mac port of lsh by Jean Pierre Stierlin.
Other free ssh programs
SSH Communications Security
The company making the original (non-free) ssh program.
GNU Privacy Guard
A free PGP replacement implementing the IETF's OpenPGP specification.
Linux FreeS/WAN
A project implementing the IETF's IPSEC end-to-end network level encryption for Linux.
The operating system, which ships with IPSEC and OpenSSH as standard since version 2.6.
The International Linux Kernel Patch
Adds kernel level support for encryption - e.g. for encrypted loopback filesystems.
The Kerberos FAQ.
The eBones Kerberos distribution<\ /a>
Other Kerberos info at KTH in Sweden.
A free implementation of Kerberos 5, also from KTH.
A free telnet implementation using the IETF's Transport Layer Security (TLS) and X.509 certificates for authentication and encryption.
The Secure Remote Password protocol, offers a simpler alternative to Kerberos.
Supports Kerberos, SRP and TLS for authentication and encryption.