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-rw-r--r--crypto/openssh/sshd.8111
1 files changed, 80 insertions, 31 deletions
diff --git a/crypto/openssh/sshd.8 b/crypto/openssh/sshd.8
index 6e283b0..117c970 100644
--- a/crypto/openssh/sshd.8
+++ b/crypto/openssh/sshd.8
@@ -34,9 +34,9 @@
.\" (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
.\" THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
.\"
-.\" $OpenBSD: sshd.8,v 1.234 2006/08/21 08:15:57 dtucker Exp $
+.\" $OpenBSD: sshd.8,v 1.246 2008/07/02 02:24:18 djm Exp $
.\" $FreeBSD$
-.Dd September 25, 1999
+.Dd $Mdocdate: July 2 2008 $
.Dt SSHD 8
.Os
.Sh NAME
@@ -45,8 +45,9 @@
.Sh SYNOPSIS
.Nm sshd
.Bk -words
-.Op Fl 46Ddeiqt
+.Op Fl 46DdeiqTt
.Op Fl b Ar bits
+.Op Fl C Ar connection_spec
.Op Fl f Ar config_file
.Op Fl g Ar login_grace_time
.Op Fl h Ar host_key_file
@@ -59,8 +60,11 @@
.Nm
(OpenSSH Daemon) is the daemon program for
.Xr ssh 1 .
-Together these programs replace rlogin and rsh, and
-provide secure encrypted communications between two untrusted hosts
+Together these programs replace
+.Xr rlogin 1
+and
+.Xr rsh 1 ,
+and provide secure encrypted communications between two untrusted hosts
over an insecure network.
.Pp
.Nm
@@ -97,7 +101,25 @@ Forces
to use IPv6 addresses only.
.It Fl b Ar bits
Specifies the number of bits in the ephemeral protocol version 1
-server key (default 768).
+server key (default 1024).
+.It Fl C Ar connection_spec
+Specify the connection parameters to use for the
+.Fl T
+extended test mode.
+If provided, any
+.Cm Match
+directives in the configuration file
+that would apply to the specified user, host, and address will be set before
+the configuration is written to standard output.
+The connection parameters are supplied as keyword=value pairs.
+The keywords are
+.Dq user ,
+.Dq host ,
+and
+.Dq addr .
+All are required and may be supplied in any order, either with multiple
+.Fl C
+options or as a comma-separated list.
.It Fl D
When this option is specified,
.Nm
@@ -118,7 +140,7 @@ Maximum is 3.
When this option is specified,
.Nm
will send the output to the standard error instead of the system log.
-.It Fl f Ar configuration_file
+.It Fl f Ar config_file
Specifies the name of the configuration file.
The default is
.Pa /etc/ssh/sshd_config .
@@ -139,6 +161,8 @@ host key files are normally not readable by anyone but root).
The default is
.Pa /etc/ssh/ssh_host_key
for protocol version 1, and
+.Pa /etc/ssh/ssh_host_rsa_key
+and
.Pa /etc/ssh/ssh_host_dsa_key
for protocol version 2.
It is possible to have multiple host key files for
@@ -187,6 +211,15 @@ Quiet mode.
Nothing is sent to the system log.
Normally the beginning,
authentication, and termination of each connection is logged.
+.It Fl T
+Extended test mode.
+Check the validity of the configuration file, output the effective configuration
+to stdout and then exit.
+Optionally,
+.Cm Match
+rules may be applied by specifying the connection parameters using one or more
+.Fl C
+options.
.It Fl t
Test mode.
Only check the validity of the configuration file and sanity of the keys.
@@ -272,7 +305,7 @@ The client selects the encryption algorithm
to use from those offered by the server.
Additionally, session integrity is provided
through a cryptographic message authentication code
-(hmac-sha1 or hmac-md5).
+(hmac-md5, hmac-sha1, umac-64 or hmac-ripemd160).
.Pp
Finally, the server and the client enter an authentication dialog.
The client tries to authenticate itself using
@@ -298,8 +331,9 @@ on Tru64,
a leading
.Ql \&*LOCKED\&*
on FreeBSD and a leading
-.Ql \&!!
-on Linux). If there is a requirement to disable password authentication
+.Ql \&!
+on most Linuxes).
+If there is a requirement to disable password authentication
for the account while allowing still public-key, then the passwd field
should be set to something other than these values (eg
.Ql NP
@@ -500,23 +534,27 @@ This option is automatically disabled if
.Cm UseLogin
is enabled.
.It Cm from="pattern-list"
-Specifies that in addition to public key authentication, the canonical name
-of the remote host must be present in the comma-separated list of
-patterns.
-The purpose
-of this option is to optionally increase security: public key authentication
-by itself does not trust the network or name servers or anything (but
-the key); however, if somebody somehow steals the key, the key
-permits an intruder to log in from anywhere in the world.
-This additional option makes using a stolen key more difficult (name
-servers and/or routers would have to be compromised in addition to
-just the key).
-.Pp
+Specifies that in addition to public key authentication, either the canonical
+name of the remote host or its IP address must be present in the
+comma-separated list of patterns.
See
.Sx PATTERNS
in
.Xr ssh_config 5
for more information on patterns.
+.Pp
+In addition to the wildcard matching that may be applied to hostnames or
+addresses, a
+.Cm from
+stanza may match IP addressess using CIDR address/masklen notation.
+.Pp
+The purpose of this option is to optionally increase security: public key
+authentication by itself does not trust the network or name servers or
+anything (but the key); however, if somebody somehow steals the key, the key
+permits an intruder to log in from anywhere in the world.
+This additional option makes using a stolen key more difficult (name
+servers and/or routers would have to be compromised in addition to
+just the key).
.It Cm no-agent-forwarding
Forbids authentication agent forwarding when this key is used for
authentication.
@@ -528,6 +566,9 @@ This might be used, e.g. in connection with the
option.
.It Cm no-pty
Prevents tty allocation (a request to allocate a pty will fail).
+.It Cm no-user-rc
+Disables execution of
+.Pa ~/.ssh/rc .
.It Cm no-X11-forwarding
Forbids X11 forwarding when this key is used for authentication.
Any X11 forward requests by the client will return an error.
@@ -679,6 +720,13 @@ This file is used in exactly the same way as
but allows host-based authentication without permitting login with
rlogin/rsh.
.Pp
+.It ~/.ssh/
+This directory is the default location for all user-specific configuration
+and authentication information.
+There is no general requirement to keep the entire contents of this directory
+secret, but the recommended permissions are read/write/execute for the user,
+and not accessible by others.
+.Pp
.It ~/.ssh/authorized_keys
Lists the public keys (RSA/DSA) that can be used for logging in as this user.
The format of this file is described above.
@@ -759,15 +807,6 @@ This file is used in exactly the same way as
but allows host-based authentication without permitting login with
rlogin/rsh.
.Pp
-.It /etc/ssh/ssh_known_hosts
-Systemwide list of known host keys.
-This file should be prepared by the
-system administrator to contain the public host keys of all machines in the
-organization.
-The format of this file is described above.
-This file should be writable only by root/the owner and
-should be world-readable.
-.Pp
.It /etc/ssh/ssh_host_key
.It /etc/ssh/ssh_host_dsa_key
.It /etc/ssh/ssh_host_rsa_key
@@ -791,6 +830,15 @@ the user so their contents can be copied to known hosts files.
These files are created using
.Xr ssh-keygen 1 .
.Pp
+.It /etc/ssh/ssh_known_hosts
+Systemwide list of known host keys.
+This file should be prepared by the
+system administrator to contain the public host keys of all machines in the
+organization.
+The format of this file is described above.
+This file should be writable only by root/the owner and
+should be world-readable.
+.Pp
.It /etc/ssh/sshd_config
Contains configuration data for
.Nm sshd .
@@ -827,6 +875,7 @@ The content of this file is not sensitive; it can be world-readable.
.Xr ssh-add 1 ,
.Xr ssh-agent 1 ,
.Xr ssh-keygen 1 ,
+.Xr ssh-keyscan 1 ,
.Xr chroot 2 ,
.Xr hosts_access 5 ,
.Xr login.conf 5 ,
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