Add BindInterface ssh_config directive and -B command-line argument

to ssh(1) that directs it to bind its outgoing connection to the
address of the specified network interface.

BindInterface prefers to use addresses that aren't loopback or link-
local, but will fall back to those if no other addresses of the
required family are available on that interface.

Based on patch by Mike Manning in bz#2820, ok dtucker@

1 files changed, 9 insertions, 2 deletions

diff --git a/usr.bin/ssh/ssh_config.5 b/usr.bin/ssh/ssh_config.5
index a128e4f0e0d..bdf41371c7a 100644
--- a/usr.bin/ssh/ssh_config.5
+++ b/usr.bin/ssh/ssh_config.5
@@ -33,8 +33,8 @@
 .\" (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: ssh_config.5,v 1.266 2018/02/16 02:40:45 djm Exp $
-.Dd $Mdocdate: February 16 2018 $
+.\" $OpenBSD: ssh_config.5,v 1.267 2018/02/23 02:34:33 djm Exp $
+.Dd $Mdocdate: February 23 2018 $
 .Dt SSH_CONFIG 5
 .Os
 .Sh NAME
@@ -254,6 +254,13 @@ The argument must be
 or
 .Cm no
 (the default).
+.It Cm BindInterface
+Use the address of the specified interface on the local machine as the
+source address of the connection.
+Note that this option does not work if
+.Cm UsePrivilegedPort
+is set to
+.Cm yes .
 .It Cm BindAddress
 Use the specified address on the local machine as the source address of
 the connection.