- djm@cvs.openbsd.org 2008/02/08 23:24:07

[openssh.git] / sshd_config.5

diff --git a/sshd_config.5 b/sshd_config.5
index 5d6fbf68c7a063bfb30fffd0421a65595eed6c97..6746f66c8a3ee57bb36ad41dc57c00a1d2c0856d 100644 (file)
--- a/sshd_config.5
+++ b/sshd_config.5
@@ -34,7 +34,7 @@
 .\" (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_config.5,v 1.79 2008/01/01 09:27:33 dtucker Exp $
+.\" $OpenBSD: sshd_config.5,v 1.80 2008/02/08 23:24:07 djm Exp $
 .Dd $Mdocdate$
 .Dt SSHD_CONFIG 5
 .Os
@@ -173,6 +173,45 @@ All authentication styles from
 are supported.
 The default is
 .Dq yes .
+.It Cm ChrootDirectory
+Specifies a path to
+.Xr chroot 2
+to after authentication.
+This path, and all its components, must be root-owned directories that are
+not writable by any other user or group.
+.Pp
+The path may contain the following tokens that are expanded at runtime once
+the connecting user has been authenticated: %% is replaced by a literal '%',
+%h is replaced by the home directory of the user being authenticated, and
+%u is replaced by the username of that user.
+.Pp
+The
+.Cm ChrootDirectory
+must contain the necessary files and directories to support the
+users' session.
+For an interactive session this requires at least a shell, typically
+.Xr sh 1 ,
+and basic
+.Pa /dev
+nodes such as
+.Xr null 4 ,
+.Xr zero 4 ,
+.Xr stdin 4 ,
+.Xr stdout 4 ,
+.Xr stderr 4 ,
+.Xr arandom 4
+and
+.Xr tty 4
+devices.
+For file transfer sessions using
+.Dq sftp ,
+no additional configuration of the environment is necessary if the
+in-process sftp server is used (see
+.Cm Subsystem
+for details.
+.Pp
+The default is not to
+.Xr chroot 2 .
 .It Cm Ciphers
 Specifies the ciphers allowed for protocol version 2.
 Multiple ciphers must be comma-separated.
@@ -740,11 +779,22 @@ The default is
 Configures an external subsystem (e.g. file transfer daemon).
 Arguments should be a subsystem name and a command (with optional arguments)
 to execute upon subsystem request.
+.Pp
 The command
 .Xr sftp-server 8
 implements the
 .Dq sftp
 file transfer subsystem.
+.Pp
+Alternately the name
+.Dq internal-sftp
+implements an in-process
+.Dq sftp
+server.
+This may simplify configurations using
+.Cm ChrootDirectory
+to force a different filesystem root on clients.
+.Pp
 By default no subsystems are defined.
 Note that this option applies to protocol version 2 only.
 .It Cm SyslogFacility