xref: /openssh-portable/ssh-keysign.8 (revision a685ae8d)
1.\" $OpenBSD: ssh-keysign.8,v 1.15 2016/02/17 07:38:19 jmc Exp $
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3.\" Copyright (c) 2002 Markus Friedl.  All rights reserved.
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25.Dd $Mdocdate: February 17 2016 $
26.Dt SSH-KEYSIGN 8
27.Os
28.Sh NAME
29.Nm ssh-keysign
30.Nd ssh helper program for host-based authentication
31.Sh SYNOPSIS
32.Nm
33.Sh DESCRIPTION
34.Nm
35is used by
36.Xr ssh 1
37to access the local host keys and generate the digital signature
38required during host-based authentication.
39.Pp
40.Nm
41is disabled by default and can only be enabled in the
42global client configuration file
43.Pa /etc/ssh/ssh_config
44by setting
45.Cm EnableSSHKeysign
46to
47.Dq yes .
48.Pp
49.Nm
50is not intended to be invoked by the user, but from
51.Xr ssh 1 .
52See
53.Xr ssh 1
54and
55.Xr sshd 8
56for more information about host-based authentication.
57.Sh FILES
58.Bl -tag -width Ds -compact
59.It Pa /etc/ssh/ssh_config
60Controls whether
61.Nm
62is enabled.
63.Pp
64.It Pa /etc/ssh/ssh_host_dsa_key
65.It Pa /etc/ssh/ssh_host_ecdsa_key
66.It Pa /etc/ssh/ssh_host_ed25519_key
67.It Pa /etc/ssh/ssh_host_rsa_key
68These files contain the private parts of the host keys used to
69generate the digital signature.
70They should be owned by root, readable only by root, and not
71accessible to others.
72Since they are readable only by root,
73.Nm
74must be set-uid root if host-based authentication is used.
75.Pp
76.It Pa /etc/ssh/ssh_host_dsa_key-cert.pub
77.It Pa /etc/ssh/ssh_host_ecdsa_key-cert.pub
78.It Pa /etc/ssh/ssh_host_ed25519_key-cert.pub
79.It Pa /etc/ssh/ssh_host_rsa_key-cert.pub
80If these files exist they are assumed to contain public certificate
81information corresponding with the private keys above.
82.El
83.Sh SEE ALSO
84.Xr ssh 1 ,
85.Xr ssh-keygen 1 ,
86.Xr ssh_config 5 ,
87.Xr sshd 8
88.Sh HISTORY
89.Nm
90first appeared in
91.Ox 3.2 .
92.Sh AUTHORS
93.An Markus Friedl Aq Mt markus@openbsd.org
94