summaryrefslogtreecommitdiff
path: root/ssh_config.5
diff options
context:
space:
mode:
authorSimon Wilkinson <simon@sxw.org.uk>2014-02-09 16:09:48 +0000
committerColin Watson <cjwatson@debian.org>2020-10-18 12:04:32 +0100
commitd1b7918f9bce6e997c7952ac795e18d09192b2a6 (patch)
tree897785ddb933a151a3d4b7f7d1b6542aee570b76 /ssh_config.5
parent2b2c99658e3e8ed452e28f88f9cdbcdfb2a461cb (diff)
GSSAPI key exchange support
This patch has been rejected upstream: "None of the OpenSSH developers are in favour of adding this, and this situation has not changed for several years. This is not a slight on Simon's patch, which is of fine quality, but just that a) we don't trust GSSAPI implementations that much and b) we don't like adding new KEX since they are pre-auth attack surface. This one is particularly scary, since it requires hooks out to typically root-owned system resources." However, quite a lot of people rely on this in Debian, and it's better to have it merged into the main openssh package rather than having separate -krb5 packages (as we used to have). It seems to have a generally good security history. Author: Simon Wilkinson <simon@sxw.org.uk> Author: Colin Watson <cjwatson@debian.org> Author: Jakub Jelen <jjelen@redhat.com> Origin: other, https://github.com/openssh-gsskex/openssh-gsskex/commits/debian/master Bug: https://bugzilla.mindrot.org/show_bug.cgi?id=1242 Last-Updated: 2020-06-07 Patch-Name: gssapi.patch
Diffstat (limited to 'ssh_config.5')
-rw-r--r--ssh_config.557
1 files changed, 57 insertions, 0 deletions
diff --git a/ssh_config.5 b/ssh_config.5
index 6be1f1aa2..bd86d000c 100644
--- a/ssh_config.5
+++ b/ssh_config.5
@@ -779,10 +779,67 @@ The default is
779Specifies whether user authentication based on GSSAPI is allowed. 779Specifies whether user authentication based on GSSAPI is allowed.
780The default is 780The default is
781.Cm no . 781.Cm no .
782.It Cm GSSAPIClientIdentity
783If set, specifies the GSSAPI client identity that ssh should use when
784connecting to the server. The default is unset, which means that the default
785identity will be used.
782.It Cm GSSAPIDelegateCredentials 786.It Cm GSSAPIDelegateCredentials
783Forward (delegate) credentials to the server. 787Forward (delegate) credentials to the server.
784The default is 788The default is
785.Cm no . 789.Cm no .
790.It Cm GSSAPIKeyExchange
791Specifies whether key exchange based on GSSAPI may be used. When using
792GSSAPI key exchange the server need not have a host key.
793The default is
794.Dq no .
795.It Cm GSSAPIRenewalForcesRekey
796If set to
797.Dq yes
798then renewal of the client's GSSAPI credentials will force the rekeying of the
799ssh connection. With a compatible server, this will delegate the renewed
800credentials to a session on the server.
801.Pp
802Checks are made to ensure that credentials are only propagated when the new
803credentials match the old ones on the originating client and where the
804receiving server still has the old set in its cache.
805.Pp
806The default is
807.Dq no .
808.Pp
809For this to work
810.Cm GSSAPIKeyExchange
811needs to be enabled in the server and also used by the client.
812.It Cm GSSAPIServerIdentity
813If set, specifies the GSSAPI server identity that ssh should expect when
814connecting to the server. The default is unset, which means that the
815expected GSSAPI server identity will be determined from the target
816hostname.
817.It Cm GSSAPITrustDns
818Set to
819.Dq yes
820to indicate that the DNS is trusted to securely canonicalize
821the name of the host being connected to. If
822.Dq no ,
823the hostname entered on the
824command line will be passed untouched to the GSSAPI library.
825The default is
826.Dq no .
827.It Cm GSSAPIKexAlgorithms
828The list of key exchange algorithms that are offered for GSSAPI
829key exchange. Possible values are
830.Bd -literal -offset 3n
831gss-gex-sha1-,
832gss-group1-sha1-,
833gss-group14-sha1-,
834gss-group14-sha256-,
835gss-group16-sha512-,
836gss-nistp256-sha256-,
837gss-curve25519-sha256-
838.Ed
839.Pp
840The default is
841.Dq gss-group14-sha256-,gss-group16-sha512-,gss-nistp256-sha256-,gss-curve25519-sha256-,gss-gex-sha1-,gss-group14-sha1- .
842This option only applies to connections using GSSAPI.
786.It Cm HashKnownHosts 843.It Cm HashKnownHosts
787Indicates that 844Indicates that
788.Xr ssh 1 845.Xr ssh 1