NAME

File::PCAP::Writer - write PCAP files with pure Perl

VERSION

Version v0.1.0

SYNOPSIS

This module writes PCAP files that can be read with tcpdump or wireshark.

    use File::PCAP::Writer;

    my $fpw = File::PCAP::Writer->new( {
        fname => 'file.pcap',
        dlt => 1,
    } );

    $fpw->packet( $tsec, $usec, $blen, $plen, $buf );

SUBROUTINES/METHODS

new( $args )

Create a new File::PCAP::Writer object.

Parameter $args is a reference to a hash, that may contain the following keys:

fname

The corresponding value is the name of the PCAP file. It defaults to file.pcap if the key is omitted.

The file is created and filled with a global PCAP header. It can be immediately read by tcpdump.

dlt

The corresponding value is the data link type that is written in the global PCAP header. It defaults to 1 (LINKTYPE_ETHERNET) if the key is omitted.

See http://www.tcpdump.org/linktypes.html for more information about link-layer header type values.

Note that this is only a hint for tcpdump or wireshark at the type of packets to expect in the PCAP file. You are responsible to add datagram packets that match the link-layer header type in the global PCAP header.

packet( $tsec, $usec, $blen, $plen, $buf )

Write a new datagram record at the end of the PCAP file.

The arguments are:

$tsec

The date and time for this packets. This value is in seconds since January 1, 1970 00:00:00 GMT.

$usec

The microseconds when this packet was captured as an offset to $tsec.

$blen

The number of bytes of the packet data saved in the file.

$plen

The length of the packet as it appeared on the network.

$buf

The actual packet data as a blob. This buffer should contain at least $blen bytes.

Note that this packet data should match the link-layer type in the global PCAP header.

DIAGNOSTICS

Can't write global header to file '$fname'

The program can't write to file $fname. This is the name of the file for the PCAP data. If $fname is file.pcap than you probably have not specified a file name explicitely.

This message appears at the time when the File::PCAP::Writer object is created. It often hints at problems with file permissions.

Can't write packet data to file '$fname'

The program can't write to file $fname. This is the name of the file for the PCAP data. If $fname is file.pcap than you probably have not specified a file name explicitely.

This message appears when new packet data shall be written. It often hints at problems with a lack of disk space.

Need a filename to write PCAP data

Since there is a default value for the filename, you probably have it overwritten with an empty filename when calling new().

AUTHOR

Mathias Weidner, <mamawe at cpan.org>

BUGS

Please report any bugs or feature requests to bug-file-pcap at rt.cpan.org, or through the web interface at http://rt.cpan.org/NoAuth/ReportBug.html?Queue=File-PCAP. I will be notified, and then you'll automatically be notified of progress on your bug as I make changes.

SUPPORT

You can find documentation for this module with the perldoc command.

    perldoc File::PCAP::Writer

You can also look for information at:

ACKNOWLEDGEMENTS

LICENSE AND COPYRIGHT

Copyright 2017 Mathias Weidner.

This program is free software; you can redistribute it and/or modify it under the terms of the the Artistic License (2.0). You may obtain a copy of the full license at:

http://www.perlfoundation.org/artistic_license_2_0

Any use, modification, and distribution of the Standard or Modified Versions is governed by this Artistic License. By using, modifying or distributing the Package, you accept this license. Do not use, modify, or distribute the Package, if you do not accept this license.

If your Modified Version has been derived from a Modified Version made by someone other than you, you are nevertheless required to ensure that your Modified Version complies with the requirements of this license.

This license does not grant you the right to use any trademark, service mark, tradename, or logo of the Copyright Holder.

This license includes the non-exclusive, worldwide, free-of-charge patent license to make, have made, use, offer to sell, sell, import and otherwise transfer the Package with respect to any patent claims licensable by the Copyright Holder that are necessarily infringed by the Package. If you institute patent litigation (including a cross-claim or counterclaim) against any party alleging that the Package constitutes direct or contributory patent infringement, then this Artistic License to you shall terminate on the date that such litigation is filed.

Disclaimer of Warranty: THE PACKAGE IS PROVIDED BY THE COPYRIGHT HOLDER AND CONTRIBUTORS "AS IS' AND WITHOUT ANY EXPRESS OR IMPLIED WARRANTIES. THE IMPLIED WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE, OR NON-INFRINGEMENT ARE DISCLAIMED TO THE EXTENT PERMITTED BY YOUR LOCAL LAW. UNLESS REQUIRED BY LAW, NO COPYRIGHT HOLDER OR CONTRIBUTOR WILL BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, OR CONSEQUENTIAL DAMAGES ARISING IN ANY WAY OUT OF THE USE OF THE PACKAGE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.