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-rw-r--r--sshd_config.552
1 files changed, 50 insertions, 2 deletions
diff --git a/sshd_config.5 b/sshd_config.5
index 55e8d8503..a5e20d1e8 100644
--- a/sshd_config.5
+++ b/sshd_config.5
@@ -58,6 +58,33 @@ Arguments may optionally be enclosed in double quotes
58.Pq \&" 58.Pq \&"
59in order to represent arguments containing spaces. 59in order to represent arguments containing spaces.
60.Pp 60.Pp
61Note that the Debian
62.Ic openssh-server
63package sets several options as standard in
64.Pa /etc/ssh/sshd_config
65which are not the default in
66.Xr sshd 8 .
67The exact list depends on whether the package was installed fresh or
68upgraded from various possible previous versions, but includes at least the
69following:
70.Pp
71.Bl -bullet -offset indent -compact
72.It
73.Cm Protocol No 2
74.It
75.Cm ChallengeResponseAuthentication No no
76.It
77.Cm X11Forwarding No yes
78.It
79.Cm PrintMotd No no
80.It
81.Cm AcceptEnv No LANG LC_*
82.It
83.Cm Subsystem No sftp /usr/lib/openssh/sftp-server
84.It
85.Cm UsePAM No yes
86.El
87.Pp
61The possible 88The possible
62keywords and their meanings are as follows (note that 89keywords and their meanings are as follows (note that
63keywords are case-insensitive and arguments are case-sensitive): 90keywords are case-insensitive and arguments are case-sensitive):
@@ -222,8 +249,7 @@ This option is only available for protocol version 2.
222By default, no banner is displayed. 249By default, no banner is displayed.
223.It Cm ChallengeResponseAuthentication 250.It Cm ChallengeResponseAuthentication
224Specifies whether challenge-response authentication is allowed (e.g. via 251Specifies whether challenge-response authentication is allowed (e.g. via
225PAM or though authentication styles supported in 252PAM).
226.Xr login.conf 5 )
227The default is 253The default is
228.Dq yes . 254.Dq yes .
229.It Cm ChrootDirectory 255.It Cm ChrootDirectory
@@ -340,6 +366,11 @@ or
340.Dq no . 366.Dq no .
341The default is 367The default is
342.Dq delayed . 368.Dq delayed .
369.It Cm DebianBanner
370Specifies whether the distribution-specified extra version suffix is
371included during initial protocol handshake.
372The default is
373.Dq yes .
343.It Cm DenyGroups 374.It Cm DenyGroups
344This keyword can be followed by a list of group name patterns, separated 375This keyword can be followed by a list of group name patterns, separated
345by spaces. 376by spaces.
@@ -743,6 +774,20 @@ are refused if the number of unauthenticated connections reaches
743Specifies whether password authentication is allowed. 774Specifies whether password authentication is allowed.
744The default is 775The default is
745.Dq yes . 776.Dq yes .
777.It Cm PermitBlacklistedKeys
778Specifies whether
779.Xr sshd 8
780should allow keys recorded in its blacklist of known-compromised keys (see
781.Xr ssh-vulnkey 1 ) .
782If
783.Dq yes ,
784then attempts to authenticate with compromised keys will be logged but
785accepted.
786If
787.Dq no ,
788then attempts to authenticate with compromised keys will be rejected.
789The default is
790.Dq no .
746.It Cm PermitEmptyPasswords 791.It Cm PermitEmptyPasswords
747When password authentication is allowed, it specifies whether the 792When password authentication is allowed, it specifies whether the
748server allows login to accounts with empty password strings. 793server allows login to accounts with empty password strings.
@@ -971,6 +1016,9 @@ This avoids infinitely hanging sessions.
971.Pp 1016.Pp
972To disable TCP keepalive messages, the value should be set to 1017To disable TCP keepalive messages, the value should be set to
973.Dq no . 1018.Dq no .
1019.Pp
1020This option was formerly called
1021.Cm KeepAlive .
974.It Cm TrustedUserCAKeys 1022.It Cm TrustedUserCAKeys
975Specifies a file containing public keys of certificate authorities that are 1023Specifies a file containing public keys of certificate authorities that are
976trusted to sign user certificates for authentication. 1024trusted to sign user certificates for authentication.