NPFCTL(8)

NPFCTL(8) | System Manager's Manual | NPFCTL(8)

# NAME

npfctl — control NPF packet filter

# SYNOPSIS

npfctl | command [arguments]

# DESCRIPTION

The npfctl command can be used to control the NPF packet filter. For a description of NPF's configuration file, see npf.conf(5).

The first argument, command, specifies the action to take. Valid commands are:

start
  Enable packet inspection using the currently loaded configuration, if any. Note that this command does not load or reload the configuration, or affect existing sessions.
stop
  Disable packet inspection. This command does not change the currently loaded configuration, or affect existing sessions.
reload [path]
  Load or reload configuration from file. The configuration file at /etc/npf.conf will be used unless a file is specified by path. All sessions will be preserved during the reload, except those which will lose NAT policy due to removal. NAT policy is determined by the translation type and address. Note that change of filter criteria will not expire associated sessions. The reload operation (i.e., replacing the ruleset, NAT policies and tables) is atomic.
flush
  Flush configuration. That is, remove all rules, tables and expire all sessions. This command does not disable packet inspection.
table tid
  List all entries in the currently loaded table specified by tid. Fail if tid does not exist.
table tid <addr/mask>
  Query the table tid for a specific IPv4 CIDR, specified by addr/mask. If no mask is specified, a single host is assumed.
table tid [add | rem] <addr/mask>
  In table tid, add or remove the IPv4 CIDR specified by <addr/mask>.
sess-save
  Save all active sessions. The data will be stored in the /var/db/npf_sessions.db file. Administrator may want to stop the packet inspection before the session saving.
sess-load
  Load saved sessions from the file. Note that original configuration should be loaded before the session loading. In a case of NAT policy changes, sessions which lose an associated policy will not be loaded. Any existing sessions during the load operation will be expired. Administrator may want to start packet inspection after the session loading.
stats
  Print various statistics.

# PERFORMANCE

Reloading the configuration is a relatively expensive operation. Therefore, frequent reloads should be avoided. Use of tables should be considered as an alternative design. See npf.conf(5) for details.

# FILES

/dev/npf
  control device
/etc/npf.conf
  default configuration file

# EXAMPLES

Starting the NPF packet filter:

    # npfctl reload
    # npfctl start

Addition and removal of entries in the table whose ID is 2:

    # npfctl table 2 add 10.0.0.1
    # npfctl table 2 rem 182.168.0.0/24

# SEE ALSO

npf.conf(5), npf_ncode(9)

# HISTORY

NPF first appeared in NetBSD 6.0.

March 24, 2011 | NetBSD 5.99