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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 449afb302..e7a5f0a08 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):
@@ -221,8 +248,7 @@ This option is only available for protocol version 2.
221By default, no banner is displayed. 248By default, no banner is displayed.
222.It Cm ChallengeResponseAuthentication 249.It Cm ChallengeResponseAuthentication
223Specifies whether challenge-response authentication is allowed (e.g. via 250Specifies whether challenge-response authentication is allowed (e.g. via
224PAM or though authentication styles supported in 251PAM).
225.Xr login.conf 5 )
226The default is 252The default is
227.Dq yes . 253.Dq yes .
228.It Cm ChrootDirectory 254.It Cm ChrootDirectory
@@ -339,6 +365,11 @@ or
339.Dq no . 365.Dq no .
340The default is 366The default is
341.Dq delayed . 367.Dq delayed .
368.It Cm DebianBanner
369Specifies whether the distribution-specified extra version suffix is
370included during initial protocol handshake.
371The default is
372.Dq yes .
342.It Cm DenyGroups 373.It Cm DenyGroups
343This keyword can be followed by a list of group name patterns, separated 374This keyword can be followed by a list of group name patterns, separated
344by spaces. 375by spaces.
@@ -792,6 +823,20 @@ are refused if the number of unauthenticated connections reaches
792Specifies whether password authentication is allowed. 823Specifies whether password authentication is allowed.
793The default is 824The default is
794.Dq yes . 825.Dq yes .
826.It Cm PermitBlacklistedKeys
827Specifies whether
828.Xr sshd 8
829should allow keys recorded in its blacklist of known-compromised keys (see
830.Xr ssh-vulnkey 1 ) .
831If
832.Dq yes ,
833then attempts to authenticate with compromised keys will be logged but
834accepted.
835If
836.Dq no ,
837then attempts to authenticate with compromised keys will be rejected.
838The default is
839.Dq no .
795.It Cm PermitEmptyPasswords 840.It Cm PermitEmptyPasswords
796When password authentication is allowed, it specifies whether the 841When password authentication is allowed, it specifies whether the
797server allows login to accounts with empty password strings. 842server allows login to accounts with empty password strings.
@@ -1020,6 +1065,9 @@ This avoids infinitely hanging sessions.
1020.Pp 1065.Pp
1021To disable TCP keepalive messages, the value should be set to 1066To disable TCP keepalive messages, the value should be set to
1022.Dq no . 1067.Dq no .
1068.Pp
1069This option was formerly called
1070.Cm KeepAlive .
1023.It Cm TrustedUserCAKeys 1071.It Cm TrustedUserCAKeys
1024Specifies a file containing public keys of certificate authorities that are 1072Specifies a file containing public keys of certificate authorities that are
1025trusted to sign user certificates for authentication. 1073trusted to sign user certificates for authentication.