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.\" $NetBSD: blacklistd.conf.5,v 1.5 2016/06/08 12:48:37 wiz Exp $
.\"
.\" Copyright (c) 2015 The NetBSD Foundation, Inc.
.\" All rights reserved.
.\"
.\" This code is derived from software contributed to The NetBSD Foundation
.\" by Christos Zoulas.
.\"
.\" Redistribution and use in source and binary forms, with or without
.\" modification, are permitted provided that the following conditions
.\" are met:
.\" 1. Redistributions of source code must retain the above copyright
.\"    notice, this list of conditions and the following disclaimer.
.\" 2. Redistributions in binary form must reproduce the above copyright
.\"    notice, this list of conditions and the following disclaimer in the
.\"    documentation and/or other materials provided with the distribution.
.\"
.\" THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
.\" ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
.\" TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
.\" PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
.\" BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
.\" CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
.\" SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
.\" INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
.\" CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
.\" ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
.\" POSSIBILITY OF SUCH DAMAGE.
.\"
.Dd June 7, 2016
.Dt BLACKLISTD.CONF 5
.Os
.Sh NAME
.Nm blacklistd.conf
.Nd configuration file format for blacklistd
.Sh DESCRIPTION
The
.Nm
files contains configuration lines for
.Xr blacklistd 8 .
It contains one entry per line, and is similar to
.Xr inetd.conf 5 .
There must be an entry for each field of the configuration file, with
entries for each field separated by a tab or a space.
Comments are denoted by a
.Dq #
at the beginning of a line.
.Pp
There are two kinds of configuration lines,
.Va local
and
.Va remote .
By default, configuration lines are
.Va local ,
i.e. the address specified refers to the addresses on the local machine.
To switch to between
.Va local
and
.Va remote
configuration lines you can specify the stanzas:
.Dq [local]
and
.Dq [remote] .
.Pp
On
.Va local
and
.Va remote
lines
.Dq *
means use the default, or wildcard match.
In addition, for
.Va remote
lines
.Dq =
means use the values from the matched
.Va local
configuration line.
.Pp
The first four fields,
.Va location ,
.Va type ,
.Va proto ,
and
.Va owner
are used to match the
.Va local
or
.Va remote
addresses, whereas the last 3 fields
.Va name ,
.Va nfail ,
and
.Va disable
are used to modify the filtering action.
.Pp
The first field denotes the
.Va location
as an address, mask, and port.
The syntax for the
.Va location
is:
.Bd -literal -offset indent
	[<address>|<interface>][/<mask>][:<port>]
.Ed
.Pp
The
.Dv address
can be an IPv4 address in numeric format, an IPv6 address
in numeric format and enclosed by square brackets, or an interface name.
Mask modifiers are not allowed on interfaces because interfaces
have multiple address in different protocols where the mask has a different
size.
.Pp
The
.Dv mask
is always numeric, but the
.Dv port
can be either numeric or symbolic.
.Pp
The second field is the socket
.Va type :
.Dv stream ,
.Dv dgram ,
or numeric.
The third field is the
.Va prococol :
.Dv tcp ,
.Dv udp ,
.Dv tcp6 ,
.Dv udp6 ,
or numeric.
The fourth file is the effective user
.Va ( owner )
of the daemon process reporting the event,
either as a username or a userid.
.Pp
The rest of the fields are controlling the behavior of the filter.
.Pp
The
.Va name
field, is the name of the packet filter rule to be used.
If the
.Va name
starts with a
.Dq - ,
then the default rulename is prepended to the given name.
If the
.Dv name
contains a
.Dq / ,
the remaining portion of the name is interpreted as the mask to be
applied to the address specified in the rule, so one can block whole
subnets for a single rule violation.
.Pp
The
.Va nfail
field contains the number of failed attempts before access is blocked,
defaulting to
.Dq *
meaning never, and the last field
.Va disable
specifies the amount of time since the last access that the blocking
rule should be active, defaulting to
.Dq *
meaning forever.
The default unit for
.Va disable
is seconds, but one can specify suffixes for different units, such as
.Dq m
for minutes
.Dq h
for hours and
.Dq d
for days.
.Pp
Matching is done first by checking the
.Va local
rules one by one, from the most specific to the least specific.
If a match is found, then the
.Va remote
rules are applied, and if a match is found the
.Va name ,
.Va nfail ,
and
.Va disable
fields can be altered by the
.Va remote
rule that matched.
.Pp
The
.Va remote
rules can be used for whitelisting specific addresses, changing the mask
size, or the rule that the packet filter uses, the number of failed attempts,
or the blocked duration.
.Sh FILES
.Bl -tag -width /etc/blacklistd.conf -compact
.It Pa /etc/blacklistd.conf
Configuration file.
.El
.Sh EXAMPLES
.Bd -literal -offset
# Block ssh, after 3 attempts for 6 hours on the bnx0 interface
[local]
# location	type	proto	owner	name	nfail	duration
bnx0:ssh	*	*	*	*	3	6h
[remote]
# Never block 1.2.3.4
1.2.3.4:ssh	*	*	*	*	*	*
# For addresses coming from 8.8.0.0/16 block class C networks instead
# individual hosts, but keep the rest of the blocking parameters the same.
8.8.0.0/16:ssh	*	*	*	/24	=	=
.Ed
.Sh SEE ALSO
.Xr blacklistctl 8 ,
.Xr blacklistd 8
.Sh HISTORY
.Nm
first appeared in
.Nx 7 .
.Fx
support for
.Nm
was implemented in
.Fx 11 .
.Sh AUTHORS
.An Christos Zoulas