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NAME

Net::Config - Local configuration data for libnet

SYNOPSIS

use Net::Config qw(%NetConfig);

DESCRIPTION

Net::Config holds configuration data for the modules in the libnet distribution. During installation you will be asked for these values.

The configuration data is held globally in a file in the perl installation tree, but a user may override any of these values by providing their own. This can be done by having a .libnetrc file in their home directory. This file should return a reference to a HASH containing the keys described below. For example

# .libnetrc
{
    nntp_hosts => [ "my_preferred_host" ],
    ph_hosts   => [ "my_ph_server" ],
}
__END__

Class Methods

Net::Config defines the following methods. They are methods as they are invoked as class methods. This is because Net::Config inherits from Net::LocalCfg so you can override these methods if you want.

requires_firewall($host)

Attempts to determine if a given host is outside your firewall. Possible return values are.

-1  Cannot lookup hostname
 0  Host is inside firewall (or there is no ftp_firewall entry)
 1  Host is outside the firewall

This is done by using hostname lookup and the local_netmask entry in the configuration data.

NetConfig Values

nntp_hosts
snpp_hosts
pop3_hosts
smtp_hosts
ph_hosts
daytime_hosts
time_hosts

Each is a reference to an array of hostnames (in order of preference), which should be used for the given protocol

inet_domain

Your internet domain name

ftp_firewall

If you have an FTP proxy firewall (NOT an HTTP or SOCKS firewall) then this value should be set to the firewall hostname. If your firewall does not listen to port 21, then this value should be set to "hostname:port" (eg "hostname:99")

ftp_firewall_type

There are many different ftp firewall products available. But unfortunately there is no standard for how to traverse a firewall. The list below shows the sequence of commands that Net::FTP will use

user        Username for remote host
pass        Password for remote host
fwuser      Username for firewall
fwpass      Password for firewall
remote.host The hostname of the remote ftp server
0

There is no firewall

1
USER user@remote.host
PASS pass
2
USER fwuser
PASS fwpass
USER user@remote.host
PASS pass
3
USER fwuser
PASS fwpass
SITE remote.site
USER user
PASS pass
4
USER fwuser
PASS fwpass
OPEN remote.site
USER user
PASS pass
5
USER user@fwuser@remote.site
PASS pass@fwpass
6
USER fwuser@remote.site
PASS fwpass
USER user
PASS pass
7
USER user@remote.host
PASS pass
AUTH fwuser
RESP fwpass
ftp_ext_passive
ftp_int_passive

FTP servers can work in passive or active mode. Active mode is when you want to transfer data you have to tell the server the address and port to connect to. Passive mode is when the server provide the address and port and you establish the connection.

With some firewalls active mode does not work as the server cannot connect to your machine (because you are behind a firewall) and the firewall does not re-write the command. In this case you should set ftp_ext_passive to a true value.

Some servers are configured to only work in passive mode. If you have one of these you can force Net::FTP to always transfer in passive mode; when not going via a firewall, by setting ftp_int_passive to a true value.

local_netmask

A reference to a list of netmask strings in the form "134.99.4.0/24". These are used by the requires_firewall function to determine if a given host is inside or outside your firewall.

The following entries are used during installation & testing on the libnet package

test_hosts

If true then make test may attempt to connect to hosts given in the configuration.

test_exists

If true then Configure will check each hostname given that it exists

EXPORTS

The following symbols are, or can be, exported by this module:

Default Exports

%NetConfig.

Optional Exports

None.

Export Tags

None.

KNOWN BUGS

None.

AUTHOR

Graham Barr <gbarr@pobox.com>.

Steve Hay <shay@cpan.org> is now maintaining libnet as of version 1.22_02.

COPYRIGHT

Copyright (C) 2000 Graham Barr. All rights reserved.

Copyright (C) 2013-2014, 2016, 2020 Steve Hay. All rights reserved.

LICENCE

This module is free software; you can redistribute it and/or modify it under the same terms as Perl itself, i.e. under the terms of either the GNU General Public License or the Artistic License, as specified in the LICENCE file.

VERSION

Version 3.15

DATE

20 March 2023

HISTORY

See the Changes file.