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BLOCKLISTD.CONF(5)            File Formats Manual           BLOCKLISTD.CONF(5)

     blocklistd.conf - configuration file format for blocklistd

     The blocklistd.conf file contains configuration entries for blocklistd(8)
     in a fashion similar to inetd.conf(5).  Only one entry per line is
     permitted.  Every entry must have all fields populated.  Each field can
     be separated by a tab or a space.  Comments are denoted by a "#" at the
     beginning of a line.

     There are two kinds of configuration lines, local and remote.  By
     default, configuration lines are local, i.e. the address specified refers
     to the addresses on the local machine.  To switch to between local and
     remote configuration lines you can specify the stanzas: "[local]" and

     On local and remote lines "*" means use the default, or wildcard match.
     In addition, for remote lines "=" means use the values from the matched
     local configuration line.

     The first four fields, location, type, proto, and owner are used to match
     the local or remote addresses, whereas the last 3 fields name, nfail, and
     disable are used to modify the filtering action.

     The first field denotes the location as an address, mask, and port.  The
     syntax for the location is:


     The 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 can have
     multiple addresses in different protocols where the mask has a different

     The mask is always numeric, but the port can be either numeric or

     The second field is the socket type: stream, dgram, or numeric.  The
     third field is the protocol: tcp, udp, tcp6, udp6, or numeric.  The
     fourth field is the effective user (owner) of the daemon process
     reporting the event, either as a username or a userid.

     The rest of the fields control the behavior of the filter.

     The name field, is the name of the packet filter rule to be used.  If the
     name starts with a "-", then the default rulename is prepended to the
     given name.  If the name contains a "/", the remaining portion of the
     name is interpreted as the mask to be applied to the address specified in
     the rule, causing a single rule violation to block the entire subnet for
     the configured prefix.

     The nfail field contains the number of failed attempts before access is
     blocked, defaulting to "*" meaning never, and the last field disable
     specifies the amount of time since the last access that the blocking rule
     should be active, defaulting to "*" meaning forever.  The default unit
     for disable is seconds, but one can specify suffixes for different units,
     such as "m" for minutes "h" for hours and "d" for days.

     Matching is done first by checking the local rules individually, in the
     order of the most specific to the least specific.  If a match is found,
     then the remote rules are applied.  The name, nfail, and disable fields
     can be altered by the remote rule that matched.

     The remote rules can be used for allowing specific addresses, changing
     the mask size, the rule that the packet filter uses, the number of failed
     attempts, or the block duration.

     /etc/blocklistd.conf  Configuration file.

             # Block ssh, after 3 attempts for 6 hours on the bnx0 interface
             # location      type    proto   owner   name    nfail   duration
             bnx0:ssh        *       *       *       *       3       6h
             # Never block
        *       *       *       *       *       *
             # For addresses coming from block class C networks instead
             # individual hosts, but keep the rest of the blocking parameters the same.
     *       *       *       /24     =       =

     blocklistctl(8), blocklistd(8)

     blocklistd.conf first appeared in NetBSD 7.  FreeBSD support for
     blocklistd.conf was implemented in FreeBSD 11.

     Christos Zoulas

NetBSD 9.99                      May 18, 2020                      NetBSD 9.99