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-rw-r--r--sshd.852
1 files changed, 40 insertions, 12 deletions
diff --git a/sshd.8 b/sshd.8
index 233b00037..ac3bf96cf 100644
--- a/sshd.8
+++ b/sshd.8
@@ -34,7 +34,7 @@
34.\" (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF 34.\" (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
35.\" THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 35.\" THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
36.\" 36.\"
37.\" $OpenBSD: sshd.8,v 1.201 2004/05/02 11:54:31 dtucker Exp $ 37.\" $OpenBSD: sshd.8,v 1.206 2005/03/01 14:59:49 jmc Exp $
38.Dd September 25, 1999 38.Dd September 25, 1999
39.Dt SSHD 8 39.Dt SSHD 8
40.Os 40.Os
@@ -106,8 +106,6 @@ to use from those offered by the server.
106Next, the server and the client enter an authentication dialog. 106Next, the server and the client enter an authentication dialog.
107The client tries to authenticate itself using 107The client tries to authenticate itself using
108.Em .rhosts 108.Em .rhosts
109authentication,
110.Em .rhosts
111authentication combined with RSA host 109authentication combined with RSA host
112authentication, RSA challenge-response authentication, or password 110authentication, RSA challenge-response authentication, or password
113based authentication. 111based authentication.
@@ -135,11 +133,6 @@ or
135.Ql \&*NP\&* 133.Ql \&*NP\&*
136). 134).
137.Pp 135.Pp
138.Em rhosts
139authentication is normally disabled
140because it is fundamentally insecure, but can be enabled in the server
141configuration file if desired.
142System security is not improved unless
143.Nm rshd , 136.Nm rshd ,
144.Nm rlogind , 137.Nm rlogind ,
145and 138and
@@ -427,7 +420,9 @@ or
427.Dq ssh-rsa . 420.Dq ssh-rsa .
428.Pp 421.Pp
429Note that lines in this file are usually several hundred bytes long 422Note that lines in this file are usually several hundred bytes long
430(because of the size of the public key encoding). 423(because of the size of the public key encoding) up to a limit of
4248 kilobytes, which permits DSA keys up to 8 kilobits and RSA
425keys up to 16 kilobits.
431You don't want to type them in; instead, copy the 426You don't want to type them in; instead, copy the
432.Pa identity.pub , 427.Pa identity.pub ,
433.Pa id_dsa.pub 428.Pa id_dsa.pub
@@ -558,6 +553,14 @@ to indicate negation: if the host name matches a negated
558pattern, it is not accepted (by that line) even if it matched another 553pattern, it is not accepted (by that line) even if it matched another
559pattern on the line. 554pattern on the line.
560.Pp 555.Pp
556Alternately, hostnames may be stored in a hashed form which hides host names
557and addresses should the file's contents be disclosed.
558Hashed hostnames start with a
559.Ql |
560character.
561Only one hashed hostname may appear on a single line and none of the above
562negation or wildcard operators may be applied.
563.Pp
561Bits, exponent, and modulus are taken directly from the RSA host key; they 564Bits, exponent, and modulus are taken directly from the RSA host key; they
562can be obtained, e.g., from 565can be obtained, e.g., from
563.Pa /etc/ssh/ssh_host_key.pub . 566.Pa /etc/ssh/ssh_host_key.pub .
@@ -589,6 +592,11 @@ and adding the host names at the front.
589closenet,...,130.233.208.41 1024 37 159...93 closenet.hut.fi 592closenet,...,130.233.208.41 1024 37 159...93 closenet.hut.fi
590cvs.openbsd.org,199.185.137.3 ssh-rsa AAAA1234.....= 593cvs.openbsd.org,199.185.137.3 ssh-rsa AAAA1234.....=
591.Ed 594.Ed
595.Bd -literal
596# A hashed hostname
597|1|JfKTdBh7rNbXkVAQCRp4OQoPfmI=|USECr3SWf1JUPsms5AqfD5QfxkM= ssh-rsa
598AAAA1234.....=
599.Ed
592.Sh FILES 600.Sh FILES
593.Bl -tag -width Ds 601.Bl -tag -width Ds
594.It Pa /etc/ssh/sshd_config 602.It Pa /etc/ssh/sshd_config
@@ -657,6 +665,20 @@ These files should be writable only by root/the owner.
657should be world-readable, and 665should be world-readable, and
658.Pa $HOME/.ssh/known_hosts 666.Pa $HOME/.ssh/known_hosts
659can, but need not be, world-readable. 667can, but need not be, world-readable.
668.It Pa /etc/motd
669See
670.Xr motd 5 .
671.It Pa $HOME/.hushlogin
672This file is used to suppress printing the last login time and
673.Pa /etc/motd ,
674if
675.Cm PrintLastLog
676and
677.Cm PrintMotd ,
678respectively,
679are enabled.
680It does not suppress printing of the banner specified by
681.Cm Banner .
660.It Pa /etc/nologin 682.It Pa /etc/nologin
661If this file exists, 683If this file exists,
662.Nm 684.Nm
@@ -670,7 +692,11 @@ Access controls that should be enforced by tcp-wrappers are defined here.
670Further details are described in 692Further details are described in
671.Xr hosts_access 5 . 693.Xr hosts_access 5 .
672.It Pa $HOME/.rhosts 694.It Pa $HOME/.rhosts
673This file contains host-username pairs, separated by a space, one per 695This file is used during
696.Cm RhostsRSAAuthentication
697and
698.Cm HostbasedAuthentication
699and contains host-username pairs, separated by a space, one per
674line. 700line.
675The given user on the corresponding host is permitted to log in 701The given user on the corresponding host is permitted to log in
676without a password. 702without a password.
@@ -691,7 +717,9 @@ However, this file is
691not used by rlogin and rshd, so using this permits access using SSH only. 717not used by rlogin and rshd, so using this permits access using SSH only.
692.It Pa /etc/hosts.equiv 718.It Pa /etc/hosts.equiv
693This file is used during 719This file is used during
694.Em rhosts 720.Cm RhostsRSAAuthentication
721and
722.Cm HostbasedAuthentication
695authentication. 723authentication.
696In the simplest form, this file contains host names, one per line. 724In the simplest form, this file contains host names, one per line.
697Users on 725Users on
@@ -710,7 +738,7 @@ Negated entries start with
710If the client host/user is successfully matched in this file, login is 738If the client host/user is successfully matched in this file, login is
711automatically permitted provided the client and server user names are the 739automatically permitted provided the client and server user names are the
712same. 740same.
713Additionally, successful RSA host authentication is normally required. 741Additionally, successful client host key authentication is required.
714This file must be writable only by root; it is recommended 742This file must be writable only by root; it is recommended
715that it be world-readable. 743that it be world-readable.
716.Pp 744.Pp