* New upstream release (LP: #535029).

  - After a transition period of about 10 years, this release disables SSH
    protocol 1 by default.  Clients and servers that need to use the
    legacy protocol must explicitly enable it in ssh_config / sshd_config
    or on the command-line.
  - Remove the libsectok/OpenSC-based smartcard code and add support for
    PKCS#11 tokens.  This support is enabled by default in the Debian
    packaging, since it now doesn't involve additional library
    dependencies (closes: #231472, LP: #16918).
  - Add support for certificate authentication of users and hosts using a
    new, minimal OpenSSH certificate format (closes: #482806).
  - Added a 'netcat mode' to ssh(1): "ssh -W host:port ...".
  - Add the ability to revoke keys in sshd(8) and ssh(1).  (For the Debian
    package, this overlaps with the key blacklisting facility added in
    openssh 1:4.7p1-9, but with different file formats and slightly
    different scopes; for the moment, I've roughly merged the two.)
  - Various multiplexing improvements, including support for requesting
    port-forwardings via the multiplex protocol (closes: #360151).
  - Allow setting an explicit umask on the sftp-server(8) commandline to
    override whatever default the user has (closes: #496843).
  - Many sftp client improvements, including tab-completion, more options,
    and recursive transfer support for get/put (LP: #33378).  The old
    mget/mput commands never worked properly and have been removed
    (closes: #270399, #428082).
  - Do not prompt for a passphrase if we fail to open a keyfile, and log
    the reason why the open failed to debug (closes: #431538).
  - Prevent sftp from crashing when given a "-" without a command.  Also,
    allow whitespace to follow a "-" (closes: #531561).

1 files changed, 39 insertions, 6 deletions

diff --git a/sshd_config.5 b/sshd_config.5
index 522ac103f..39ef781ff 100644
--- a/sshd_config.5
+++ b/sshd_config.5
@@ -34,8 +34,8 @@
 .\" (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 1.106 2009/04/21 15:13:17 stevesk Exp $
-.Dd $Mdocdate: April 21 2009 $
+.\" $OpenBSD: sshd_config.5,v 1.120 2010/03/04 23:17:25 djm Exp $
+.Dd $Mdocdate: March 4 2010 $
 .Dt SSHD_CONFIG 5
 .Os
 .Sh NAME
@@ -208,16 +208,16 @@ PAM).
 The default is
 .Dq yes .
 .It Cm ChrootDirectory
-Specifies a path to
+Specifies the pathname of a directory to
 .Xr chroot 2
 to after authentication.
-This path, and all its components, must be root-owned directories that are
+All components of the pathname must be root-owned directories that are
 not writable by any other user or group.
 After the chroot,
 .Xr sshd 8
 changes the working directory to the user's home directory.
 .Pp
-The path may contain the following tokens that are expanded at runtime once
+The pathname 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.
@@ -470,6 +470,14 @@ uses the name supplied by the client rather than
 attempting to resolve the name from the TCP connection itself.
 The default is
 .Dq no .
+.It Cm HostCertificate
+Specifies a file containing a public host certificate.
+The certificate's public key must match a private host key already specified
+by
+.Cm HostKey .
+The default behaviour of
+.Xr sshd 8
+is not to load any certificates.
 .It Cm HostKey
 Specifies a file containing a private host key
 used by SSH.
@@ -673,6 +681,7 @@ Available keywords are
 .Cm PermitEmptyPasswords ,
 .Cm PermitOpen ,
 .Cm PermitRootLogin ,
+.Cm PubkeyAuthentication ,
 .Cm RhostsRSAAuthentication ,
 .Cm RSAAuthentication ,
 .Cm X11DisplayOffset ,
@@ -865,7 +874,7 @@ and
 .Sq 2 .
 Multiple versions must be comma-separated.
 The default is
-.Dq 2,1 .
+.Sq 2 .
 Note that the order of the protocol list does not indicate preference,
 because the client selects among multiple protocol versions offered
 by the server.
@@ -878,6 +887,11 @@ Specifies whether public key authentication is allowed.
 The default is
 .Dq yes .
 Note that this option applies to protocol version 2 only.
+.It Cm RevokedKeys
+Specifies a list of revoked public keys.
+Keys listed in this file will be refused for public key authentication.
+Note that if this file is not readable, then public key authentication will
+be refused for all users.
 .It Cm RhostsRSAAuthentication
 Specifies whether rhosts or /etc/hosts.equiv authentication together
 with successful RSA host authentication is allowed.
@@ -901,6 +915,9 @@ This is normally desirable because novices sometimes accidentally leave their
 directory or files world-writable.
 The default is
 .Dq yes .
+Note that this does not apply to
+.Cm ChrootDirectory ,
+whose permissions and ownership are checked unconditionally.
 .It Cm Subsystem
 Configures an external subsystem (e.g. file transfer daemon).
 Arguments should be a subsystem name and a command (with optional arguments)
@@ -953,6 +970,22 @@ To disable TCP keepalive messages, the value should be set to
 .Pp
 This option was formerly called
 .Cm KeepAlive .
+.It Cm TrustedUserCAKeys
+Specifies a file containing public keys of certificate authorities that are
+trusted to sign user certificates for authentication.
+Keys are listed one per line; empty lines and comments starting with
+.Ql #
+are allowed.
+If a certificate is presented for authentication and has its signing CA key
+listed in this file, then it may be used for authentication for any user
+listed in the certificate's principals list.
+Note that certificates that lack a list of principals will not be permitted
+for authentication using
+.Cm TrustedUserCAKeys .
+For more details on certificates, see the
+.Sx CERTIFICATES
+section in
+.Xr ssh-keygen 1 .
 .It Cm UseDNS
 Specifies whether
 .Xr sshd 8