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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 ef4164edd..22e7edc94 100644
--- a/sshd_config.5
+++ b/sshd_config.5
@@ -57,6 +57,33 @@ Arguments may optionally be enclosed in double quotes
57.Pq \&" 57.Pq \&"
58in order to represent arguments containing spaces. 58in order to represent arguments containing spaces.
59.Pp 59.Pp
60Note that the Debian
61.Ic openssh-server
62package sets several options as standard in
63.Pa /etc/ssh/sshd_config
64which are not the default in
65.Xr sshd 8 .
66The exact list depends on whether the package was installed fresh or
67upgraded from various possible previous versions, but includes at least the
68following:
69.Pp
70.Bl -bullet -offset indent -compact
71.It
72.Cm Protocol No 2
73.It
74.Cm ChallengeResponseAuthentication No no
75.It
76.Cm X11Forwarding No yes
77.It
78.Cm PrintMotd No no
79.It
80.Cm AcceptEnv No LANG LC_*
81.It
82.Cm Subsystem No sftp /usr/lib/openssh/sftp-server
83.It
84.Cm UsePAM No yes
85.El
86.Pp
60The possible 87The possible
61keywords and their meanings are as follows (note that 88keywords and their meanings are as follows (note that
62keywords are case-insensitive and arguments are case-sensitive): 89keywords are case-insensitive and arguments are case-sensitive):
@@ -224,8 +251,7 @@ This option is only available for protocol version 2.
224By default, no banner is displayed. 251By default, no banner is displayed.
225.It Cm ChallengeResponseAuthentication 252.It Cm ChallengeResponseAuthentication
226Specifies whether challenge-response authentication is allowed (e.g. via 253Specifies whether challenge-response authentication is allowed (e.g. via
227PAM or though authentication styles supported in 254PAM).
228.Xr login.conf 5 )
229The default is 255The default is
230.Dq yes . 256.Dq yes .
231.It Cm ChrootDirectory 257.It Cm ChrootDirectory
@@ -342,6 +368,11 @@ or
342.Dq no . 368.Dq no .
343The default is 369The default is
344.Dq delayed . 370.Dq delayed .
371.It Cm DebianBanner
372Specifies whether the distribution-specified extra version suffix is
373included during initial protocol handshake.
374The default is
375.Dq yes .
345.It Cm DenyGroups 376.It Cm DenyGroups
346This keyword can be followed by a list of group name patterns, separated 377This keyword can be followed by a list of group name patterns, separated
347by spaces. 378by spaces.
@@ -803,6 +834,20 @@ are refused if the number of unauthenticated connections reaches
803Specifies whether password authentication is allowed. 834Specifies whether password authentication is allowed.
804The default is 835The default is
805.Dq yes . 836.Dq yes .
837.It Cm PermitBlacklistedKeys
838Specifies whether
839.Xr sshd 8
840should allow keys recorded in its blacklist of known-compromised keys (see
841.Xr ssh-vulnkey 1 ) .
842If
843.Dq yes ,
844then attempts to authenticate with compromised keys will be logged but
845accepted.
846If
847.Dq no ,
848then attempts to authenticate with compromised keys will be rejected.
849The default is
850.Dq no .
806.It Cm PermitEmptyPasswords 851.It Cm PermitEmptyPasswords
807When password authentication is allowed, it specifies whether the 852When password authentication is allowed, it specifies whether the
808server allows login to accounts with empty password strings. 853server allows login to accounts with empty password strings.
@@ -1034,6 +1079,9 @@ This avoids infinitely hanging sessions.
1034.Pp 1079.Pp
1035To disable TCP keepalive messages, the value should be set to 1080To disable TCP keepalive messages, the value should be set to
1036.Dq no . 1081.Dq no .
1082.Pp
1083This option was formerly called
1084.Cm KeepAlive .
1037.It Cm TrustedUserCAKeys 1085.It Cm TrustedUserCAKeys
1038Specifies a file containing public keys of certificate authorities that are 1086Specifies a file containing public keys of certificate authorities that are
1039trusted to sign user certificates for authentication. 1087trusted to sign user certificates for authentication.