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-rw-r--r--sshd.873
1 files changed, 56 insertions, 17 deletions
diff --git a/sshd.8 b/sshd.8
index b53456f1a..ae7957648 100644
--- a/sshd.8
+++ b/sshd.8
@@ -34,8 +34,8 @@
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 1.237 2007/06/07 19:37:34 pvalchev Exp $ 37.\" $OpenBSD: sshd.8,v 1.246 2008/07/02 02:24:18 djm Exp $
38.Dd $Mdocdate: August 16 2007 $ 38.Dd $Mdocdate: July 2 2008 $
39.Dt SSHD 8 39.Dt SSHD 8
40.Os 40.Os
41.Sh NAME 41.Sh NAME
@@ -44,8 +44,9 @@
44.Sh SYNOPSIS 44.Sh SYNOPSIS
45.Nm sshd 45.Nm sshd
46.Bk -words 46.Bk -words
47.Op Fl 46Ddeiqt 47.Op Fl 46DdeiqTt
48.Op Fl b Ar bits 48.Op Fl b Ar bits
49.Op Fl C Ar connection_spec
49.Op Fl f Ar config_file 50.Op Fl f Ar config_file
50.Op Fl g Ar login_grace_time 51.Op Fl g Ar login_grace_time
51.Op Fl h Ar host_key_file 52.Op Fl h Ar host_key_file
@@ -99,7 +100,25 @@ Forces
99to use IPv6 addresses only. 100to use IPv6 addresses only.
100.It Fl b Ar bits 101.It Fl b Ar bits
101Specifies the number of bits in the ephemeral protocol version 1 102Specifies the number of bits in the ephemeral protocol version 1
102server key (default 768). 103server key (default 1024).
104.It Fl C Ar connection_spec
105Specify the connection parameters to use for the
106.Fl T
107extended test mode.
108If provided, any
109.Cm Match
110directives in the configuration file
111that would apply to the specified user, host, and address will be set before
112the configuration is written to standard output.
113The connection parameters are supplied as keyword=value pairs.
114The keywords are
115.Dq user ,
116.Dq host ,
117and
118.Dq addr .
119All are required and may be supplied in any order, either with multiple
120.Fl C
121options or as a comma-separated list.
103.It Fl D 122.It Fl D
104When this option is specified, 123When this option is specified,
105.Nm 124.Nm
@@ -194,6 +213,15 @@ authentication, and termination of each connection is logged.
194If a second 213If a second
195.Fl q 214.Fl q
196is given then nothing is sent to the system log. 215is given then nothing is sent to the system log.
216.It Fl T
217Extended test mode.
218Check the validity of the configuration file, output the effective configuration
219to stdout and then exit.
220Optionally,
221.Cm Match
222rules may be applied by specifying the connection parameters using one or more
223.Fl C
224options.
197.It Fl t 225.It Fl t
198Test mode. 226Test mode.
199Only check the validity of the configuration file and sanity of the keys. 227Only check the validity of the configuration file and sanity of the keys.
@@ -506,23 +534,27 @@ This option is automatically disabled if
506.Cm UseLogin 534.Cm UseLogin
507is enabled. 535is enabled.
508.It Cm from="pattern-list" 536.It Cm from="pattern-list"
509Specifies that in addition to public key authentication, the canonical name 537Specifies that in addition to public key authentication, either the canonical
510of the remote host must be present in the comma-separated list of 538name of the remote host or its IP address must be present in the
511patterns. 539comma-separated list of patterns.
512The purpose
513of this option is to optionally increase security: public key authentication
514by itself does not trust the network or name servers or anything (but
515the key); however, if somebody somehow steals the key, the key
516permits an intruder to log in from anywhere in the world.
517This additional option makes using a stolen key more difficult (name
518servers and/or routers would have to be compromised in addition to
519just the key).
520.Pp
521See 540See
522.Sx PATTERNS 541.Sx PATTERNS
523in 542in
524.Xr ssh_config 5 543.Xr ssh_config 5
525for more information on patterns. 544for more information on patterns.
545.Pp
546In addition to the wildcard matching that may be applied to hostnames or
547addresses, a
548.Cm from
549stanza may match IP addressess using CIDR address/masklen notation.
550.Pp
551The purpose of this option is to optionally increase security: public key
552authentication by itself does not trust the network or name servers or
553anything (but the key); however, if somebody somehow steals the key, the key
554permits an intruder to log in from anywhere in the world.
555This additional option makes using a stolen key more difficult (name
556servers and/or routers would have to be compromised in addition to
557just the key).
526.It Cm no-agent-forwarding 558.It Cm no-agent-forwarding
527Forbids authentication agent forwarding when this key is used for 559Forbids authentication agent forwarding when this key is used for
528authentication. 560authentication.
@@ -535,7 +567,7 @@ option.
535.It Cm no-pty 567.It Cm no-pty
536Prevents tty allocation (a request to allocate a pty will fail). 568Prevents tty allocation (a request to allocate a pty will fail).
537.It Cm no-user-rc 569.It Cm no-user-rc
538Disables execution of 570Disables execution of
539.Pa ~/.ssh/rc . 571.Pa ~/.ssh/rc .
540.It Cm no-X11-forwarding 572.It Cm no-X11-forwarding
541Forbids X11 forwarding when this key is used for authentication. 573Forbids X11 forwarding when this key is used for authentication.
@@ -688,6 +720,13 @@ This file is used in exactly the same way as
688but allows host-based authentication without permitting login with 720but allows host-based authentication without permitting login with
689rlogin/rsh. 721rlogin/rsh.
690.Pp 722.Pp
723.It ~/.ssh/
724This directory is the default location for all user-specific configuration
725and authentication information.
726There is no general requirement to keep the entire contents of this directory
727secret, but the recommended permissions are read/write/execute for the user,
728and not accessible by others.
729.Pp
691.It ~/.ssh/authorized_keys 730.It ~/.ssh/authorized_keys
692Lists the public keys (RSA/DSA) that can be used for logging in as this user. 731Lists the public keys (RSA/DSA) that can be used for logging in as this user.
693The format of this file is described above. 732The format of this file is described above.