OpenSSH 5.4 couples standard local input with server ports
Following a transition period of more than 10 years, OpenSSH 5.4 finally disables, by default, the old SSH protocol version 1. The legacy SSH version, which is no longer considered secure, can still be used by adjusting the appropriate settings in the configuration file. Where certificates are used to authenticate users and computers, version 5.4 offers a new minimal OpenSSH format. Key pairs for users can be revoked using the new RevokedKeys option. Host keys can be revoked in the known_hosts file.
Using the -W switch and a host:port argument, OpenSSH 5.4 can be started in netcat mode, which connects a local computer's standard input channel (stdio) to a port on a remote PC. The SFTP server, which carries out FTP-like file transfer, now protects file sharing settings from being overwritten (read-only mode) and can, if required, set explicit privileges when generating new files (umask) at the command line. The SFTP client now has tab completion for commands and paths and supports recursive get and put commands which allows entire file trees to be transferred between client and server. Further details and a list of bug fixes can be found in the release notes.
OpenSSH is available under a BSD licence and is funded through donations.