NFNL_OSF(8)                                           NFNL_OSF(8)

     NAME
          nfnl_osf - OS fingerprint loader utility

     SYNOPSIS
          nfnl_osf -f fingerprints [ -d ]

     DESCRIPTION
          The nfnl_osf utility allows to load a set of operating sys-
          tem signatures into the kernel for later matching against
          using iptables' osf match.

     OPTIONS
          -f fingerprints
               Read signatures from file fingerprints.

          -d   Instead of adding the signatures from fingerprints into
               the kernel, remove them.

     EXIT STATUS
          Exit status is 0 if command succeeded, otherwise a negative
          return code indicates the type of error which happened:

          -1   Illegal arguments passed, fingerprints file not read-
               able or failure in netlink communication.

          -ENOENT
               Fingerprints file not specified.

          -EINVAL
               Netlink handle initialization failed or fingerprints
               file format invalid.

     FILES
          An up to date set of operating system signatures can be
          downloaded from http://www.openbsd.org/cgi-
          bin/cvsweb/src/etc/pf.os .

     SEE ALSO
          The description of osf match in iptables-extensions(8) con-
          tains further information about the topic as well as example

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     NFNL_OSF(8)                                           NFNL_OSF(8)

          nfnl_osf invocations.

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