$Mdocdate: May 31 2007 $ SSH-KEYSIGN 8

### NAME

ssh-keysign - ssh helper program for host-based authentication

### SYNOPSIS

ssh-keysign

### DESCRIPTION

ssh-keysign is used by ssh(1) to access the local host keys and generate the digital signature required during host-based authentication with SSH protocol version 2.

ssh-keysign is disabled by default and can only be enabled in the global client configuration file ```/etc/ssh/ssh_config` by setting EnableSSHKeysign to ``yes''.

ssh-keysign is not intended to be invoked by the user, but from ssh(1). See ssh(1) and sshd(8) for more information about host-based authentication.

### FILES

```/etc/ssh/ssh_config`
  Controls whether ssh-keysign is enabled.

```/etc/ssh/ssh_host_dsa_key,``/etc/ssh/ssh_host_rsa_key`
  These files contain the private parts of the host keys used to generate the digital signature. They should be owned by root, readable only by root, and not accessible to others. Since they are readable only by root, ssh-keysign must be set-uid root if host-based authentication is used.

### SEE ALSO

ssh(1), ssh-keygen(1), ssh_config(5), sshd(8)

### HISTORY

ssh-keysign first appeared in OpenBSD3.2.

### AUTHORS

Markus Friedl <markus@openbsd.org>