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-rw-r--r--sshd_config.546
1 files changed, 45 insertions, 1 deletions
diff --git a/sshd_config.5 b/sshd_config.5
index e58b7cfc7..d5f19ea3d 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):
@@ -557,7 +584,7 @@ The default is 120 seconds.
557Gives the verbosity level that is used when logging messages from 584Gives the verbosity level that is used when logging messages from
558.Xr sshd 8 . 585.Xr sshd 8 .
559The possible values are: 586The possible values are:
560QUIET, FATAL, ERROR, INFO, VERBOSE, DEBUG, DEBUG1, DEBUG2, and DEBUG3. 587SILENT, QUIET, FATAL, ERROR, INFO, VERBOSE, DEBUG, DEBUG1, DEBUG2, and DEBUG3.
561The default is INFO. 588The default is INFO.
562DEBUG and DEBUG1 are equivalent. 589DEBUG and DEBUG1 are equivalent.
563DEBUG2 and DEBUG3 each specify higher levels of debugging output. 590DEBUG2 and DEBUG3 each specify higher levels of debugging output.
@@ -673,6 +700,20 @@ are refused if the number of unauthenticated connections reaches
673Specifies whether password authentication is allowed. 700Specifies whether password authentication is allowed.
674The default is 701The default is
675.Dq yes . 702.Dq yes .
703.It Cm PermitBlacklistedKeys
704Specifies whether
705.Xr sshd 8
706should allow keys recorded in its blacklist of known-compromised keys (see
707.Xr ssh-vulnkey 1 ) .
708If
709.Dq yes ,
710then attempts to authenticate with compromised keys will be logged but
711accepted.
712If
713.Dq no ,
714then attempts to authenticate with compromised keys will be rejected.
715The default is
716.Dq no .
676.It Cm PermitEmptyPasswords 717.It Cm PermitEmptyPasswords
677When password authentication is allowed, it specifies whether the 718When password authentication is allowed, it specifies whether the
678server allows login to accounts with empty password strings. 719server allows login to accounts with empty password strings.
@@ -893,6 +934,9 @@ This avoids infinitely hanging sessions.
893.Pp 934.Pp
894To disable TCP keepalive messages, the value should be set to 935To disable TCP keepalive messages, the value should be set to
895.Dq no . 936.Dq no .
937.Pp
938This option was formerly called
939.Cm KeepAlive .
896.It Cm UseDNS 940.It Cm UseDNS
897Specifies whether 941Specifies whether
898.Xr sshd 8 942.Xr sshd 8