1*1c7715ddSchristos.\" $NetBSD: ssh-keysign.8,v 1.15 2024/07/08 22:33:44 christos Exp $ 2*1c7715ddSchristos.\" $OpenBSD: ssh-keysign.8,v 1.18 2024/06/17 08:30:29 djm Exp $ 3ca32bd8dSchristos.\" 4ca32bd8dSchristos.\" Copyright (c) 2002 Markus Friedl. All rights reserved. 5ca32bd8dSchristos.\" 6ca32bd8dSchristos.\" Redistribution and use in source and binary forms, with or without 7ca32bd8dSchristos.\" modification, are permitted provided that the following conditions 8ca32bd8dSchristos.\" are met: 9ca32bd8dSchristos.\" 1. Redistributions of source code must retain the above copyright 10ca32bd8dSchristos.\" notice, this list of conditions and the following disclaimer. 11ca32bd8dSchristos.\" 2. Redistributions in binary form must reproduce the above copyright 12ca32bd8dSchristos.\" notice, this list of conditions and the following disclaimer in the 13ca32bd8dSchristos.\" documentation and/or other materials provided with the distribution. 14ca32bd8dSchristos.\" 15ca32bd8dSchristos.\" THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR 16ca32bd8dSchristos.\" IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES 17ca32bd8dSchristos.\" OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. 18ca32bd8dSchristos.\" IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, 19ca32bd8dSchristos.\" INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT 20ca32bd8dSchristos.\" NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, 21ca32bd8dSchristos.\" DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY 22ca32bd8dSchristos.\" THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 23ca32bd8dSchristos.\" (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF 24ca32bd8dSchristos.\" THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 25ca32bd8dSchristos.\" 26*1c7715ddSchristos.Dd June 17 2024 27ca32bd8dSchristos.Dt SSH-KEYSIGN 8 28ca32bd8dSchristos.Os 29ca32bd8dSchristos.Sh NAME 30ca32bd8dSchristos.Nm ssh-keysign 31ed75d7a8Schristos.Nd OpenSSH helper for host-based authentication 32ca32bd8dSchristos.Sh SYNOPSIS 33ca32bd8dSchristos.Nm 34ca32bd8dSchristos.Sh DESCRIPTION 35ca32bd8dSchristos.Nm 36ca32bd8dSchristosis used by 37ca32bd8dSchristos.Xr ssh 1 38ca32bd8dSchristosto access the local host keys and generate the digital signature 3979976551Schristosrequired during host-based authentication. 40ca32bd8dSchristos.Pp 41ca32bd8dSchristos.Nm 42ca32bd8dSchristosis disabled by default and can only be enabled in the 43ca32bd8dSchristosglobal client configuration file 44ca32bd8dSchristos.Pa /etc/ssh/ssh_config 45ca32bd8dSchristosby setting 46ca32bd8dSchristos.Cm EnableSSHKeysign 47ca32bd8dSchristosto 48ca32bd8dSchristos.Dq yes . 49ca32bd8dSchristos.Pp 50ca32bd8dSchristos.Nm 51ca32bd8dSchristosis not intended to be invoked by the user, but from 52ca32bd8dSchristos.Xr ssh 1 . 53ca32bd8dSchristosSee 54ca32bd8dSchristos.Xr ssh 1 55ca32bd8dSchristosand 56ca32bd8dSchristos.Xr sshd 8 57ca32bd8dSchristosfor more information about host-based authentication. 58ca32bd8dSchristos.Sh FILES 5934b27b53Sadam.Bl -tag -width Ds -compact 60ca32bd8dSchristos.It Pa /etc/ssh/ssh_config 61ca32bd8dSchristosControls whether 62ca32bd8dSchristos.Nm 63ca32bd8dSchristosis enabled. 6434b27b53Sadam.Pp 65185c8f97Schristos.It Pa /etc/ssh/ssh_host_ecdsa_key 668a4530f9Schristos.It Pa /etc/ssh/ssh_host_ed25519_key 6734b27b53Sadam.It Pa /etc/ssh/ssh_host_rsa_key 68ca32bd8dSchristosThese files contain the private parts of the host keys used to 69ca32bd8dSchristosgenerate the digital signature. 70ca32bd8dSchristosThey should be owned by root, readable only by root, and not 71ca32bd8dSchristosaccessible to others. 72ca32bd8dSchristosSince they are readable only by root, 73ca32bd8dSchristos.Nm 74ca32bd8dSchristosmust be set-uid root if host-based authentication is used. 7534b27b53Sadam.Pp 76185c8f97Schristos.It Pa /etc/ssh/ssh_host_ecdsa_key-cert.pub 778a4530f9Schristos.It Pa /etc/ssh/ssh_host_ed25519_key-cert.pub 7834b27b53Sadam.It Pa /etc/ssh/ssh_host_rsa_key-cert.pub 79c4271af5SchristosIf these files exist, they are assumed to contain public certificate 8034b27b53Sadaminformation corresponding with the private keys above. 81ca32bd8dSchristos.El 82ca32bd8dSchristos.Sh SEE ALSO 83ca32bd8dSchristos.Xr ssh 1 , 84ca32bd8dSchristos.Xr ssh-keygen 1 , 85ca32bd8dSchristos.Xr ssh_config 5 , 86ca32bd8dSchristos.Xr sshd 8 87ca32bd8dSchristos.Sh HISTORY 88ca32bd8dSchristos.Nm 89ca32bd8dSchristosfirst appeared in 90ca32bd8dSchristos.Ox 3.2 . 91ca32bd8dSchristos.Sh AUTHORS 92a5684d07Swiz.An Markus Friedl Aq Mt markus@openbsd.org 93