[p5sagit/p5-mst-13.2.git] / lib / Net / Config.pm

# Net::Config.pm
#
# Copyright (c) 2000 Graham Barr <gbarr@pobox.com>. All rights reserved.
# This program is free software; you can redistribute it and/or
# modify it under the same terms as Perl itself.

package Net::Config;

require Exporter;
use vars qw(@ISA @EXPORT %NetConfig $VERSION $CONFIGURE $LIBNET_CFG);
use Socket qw(inet_aton inet_ntoa);
use strict;

@EXPORT  = qw(%NetConfig);
@ISA     = qw(Net::LocalCfg Exporter);
$VERSION = "1.05"; # $Id: //depot/libnet/Net/Config.pm#9 $

eval { local $SIG{__DIE__}; require Net::LocalCfg };

%NetConfig = (
    nntp_hosts => [],
    snpp_hosts => [],
    pop3_hosts => [],
    smtp_hosts => [],
    ph_hosts => [],
    daytime_hosts => [],
    time_hosts => [],
    inet_domain => undef,
    ftp_firewall => undef,
    ftp_ext_passive => 0,
    ftp_int_passive => 0,
    test_hosts => 1,
    test_exist => 1,
);

my $file = __FILE__;
my $ref;
$file =~ s/Config.pm/libnet.cfg/;
if ( -f $file ) {
    $ref = eval { do $file };
    if (ref($ref) eq 'HASH') {
	%NetConfig = (%NetConfig, %{ $ref });
	$LIBNET_CFG = $file;
    }
}
if ($< == $> and !$CONFIGURE)  {
    my $home = eval { (getpwuid($>))[7] } || $ENV{HOME};
    if (defined $home) {
	$file = $home . "/.libnetrc";
	$ref = eval { do $file } if -f $file;
	%NetConfig = (%NetConfig, %{ $ref })
	    if ref($ref) eq 'HASH';	
    }
}
my ($k,$v);
while(($k,$v) = each %NetConfig) {
    $v = [ $v ]
	if($k =~ /_hosts$/ && !ref($v));
}

# Take a hostname and determine if it is inside te firewall

sub requires_firewall {
    shift; # ignore package
    my $host = shift;

    return 0 unless defined $NetConfig{'ftp_firewall'};

    $host = inet_aton($host) or return -1;
    $host = inet_ntoa($host);

    if(exists $NetConfig{'local_netmask'}) {
	my $quad = unpack("N",pack("C*",split(/\./,$host)));
	my $list = $NetConfig{'local_netmask'};
	$list = [$list] unless ref($list);
	foreach (@$list) {
	    my($net,$bits) = (m#^(\d+\.\d+\.\d+\.\d+)/(\d+)$#) or next;
	    my $mask = ~0 << (32 - $bits);
	    my $addr = unpack("N",pack("C*",split(/\./,$net)));

	    return 0 if (($addr & $mask) == ($quad & $mask));
	}
	return 1;
    }

    return 0;
}

use vars qw(*is_external);
*is_external = \&requires_firewall;

1;

__END__

=head1 NAME

Net::Config - Local configuration data for libnet

=head1 SYNOPSYS

    use Net::Config qw(%NetConfig);

=head1 DESCRIPTION

C<Net::Config> holds configuration data for the modules in the libnet
distribuion. 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 C<.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_prefered_host" ],
	ph_hosts   => [ "my_ph_server" ],
    }
    __END__

=head1 METHODS

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

=over 4

=item 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 C<local_netmask> entry in
the configuration data.

=back

=head1 NetConfig VALUES

=over 4

=item nntp_hosts

=item snpp_hosts

=item pop3_hosts

=item smtp_hosts

=item ph_hosts

=item daytime_hosts

=item time_hosts

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

=item inet_domain

Your internet domain name

=item ftp_firewall

If you have an FTP proxy firewall (B<NOT> a 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
C<"hostname:port"> (eg C<"hostname:99">)

=item 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

=over 4

=item 0

There is no firewall

=item 1

     USER user@remote.host
     PASS pass

=item 2

     USER fwuser
     PASS fwpass
     USER user@remote.host
     PASS pass

=item 3

     USER fwuser
     PASS fwpass
     SITE remote.site
     USER user
     PASS pass

=item 4

     USER fwuser
     PASS fwpass
     OPEN remote.site
     USER user
     PASS pass

=item 5

     USER user@fwuser@remote.site
     PASS pass@fwpass

=item 6

     USER fwuser@remote.site
     PASS fwpass
     USER user
     PASS pass

=item 7

     USER user@remote.host
     PASS pass
     AUTH fwuser
     RESP fwpass

=back

=item ftp_ext_passive

=item ftp_int_pasive

FTP servers normally work on a non-passive mode. That is when you want to
transfer data you have to tell the server the address and port to
connect to.

With some firewalls this 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 C<ftp_ext_passive>
to a I<true> value.

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

=item local_netmask

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

=back

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

=over 4

=item test_hosts

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

=item test_exists

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

=back

=for html <hr>

I<$Id: //depot/libnet/Net/Config.pm#9 $>

=cut
Commit	Line	Data
686337f3	1	# Net::Config.pm
	2	#
	3	# Copyright (c) 2000 Graham Barr <gbarr@pobox.com>. All rights reserved.
	4	# This program is free software; you can redistribute it and/or
	5	# modify it under the same terms as Perl itself.
406c51ee	6
406c51ee	7	package Net::Config;
406c51ee	8
	9	require Exporter;
	10	use vars qw(@ISA @EXPORT %NetConfig $VERSION $CONFIGURE $LIBNET_CFG);
	11	use Socket qw(inet_aton inet_ntoa);
	12	use strict;
	13
	14	@EXPORT = qw(%NetConfig);
	15	@ISA = qw(Net::LocalCfg Exporter);
686337f3	16	$VERSION = "1.05"; # $Id: //depot/libnet/Net/Config.pm#9 $
406c51ee	17
	18	eval { local $SIG{__DIE__}; require Net::LocalCfg };
	19
	20	%NetConfig = (
	21	nntp_hosts => [],
	22	snpp_hosts => [],
	23	pop3_hosts => [],
	24	smtp_hosts => [],
	25	ph_hosts => [],
	26	daytime_hosts => [],
	27	time_hosts => [],
	28	inet_domain => undef,
	29	ftp_firewall => undef,
	30	ftp_ext_passive => 0,
	31	ftp_int_passive => 0,
	32	test_hosts => 1,
	33	test_exist => 1,
	34	);
	35
	36	my $file = __FILE__;
	37	my $ref;
	38	$file =~ s/Config.pm/libnet.cfg/;
	39	if ( -f $file ) {
	40	$ref = eval { do $file };
	41	if (ref($ref) eq 'HASH') {
	42	%NetConfig = (%NetConfig, %{ $ref });
	43	$LIBNET_CFG = $file;
	44	}
	45	}
	46	if ($< == $> and !$CONFIGURE) {
686337f3	47	my $home = eval { (getpwuid($>))[7] } \|\| $ENV{HOME};
	48	if (defined $home) {
	49	$file = $home . "/.libnetrc";
	50	$ref = eval { do $file } if -f $file;
	51	%NetConfig = (%NetConfig, %{ $ref })
	52	if ref($ref) eq 'HASH';
	53	}
406c51ee	54	}
	55	my ($k,$v);
	56	while(($k,$v) = each %NetConfig) {
	57	$v = [ $v ]
	58	if($k =~ /_hosts$/ && !ref($v));
	59	}
	60
	61	# Take a hostname and determine if it is inside te firewall
	62
	63	sub requires_firewall {
	64	shift; # ignore package
	65	my $host = shift;
	66
	67	return 0 unless defined $NetConfig{'ftp_firewall'};
	68
	69	$host = inet_aton($host) or return -1;
	70	$host = inet_ntoa($host);
	71
	72	if(exists $NetConfig{'local_netmask'}) {
	73	my $quad = unpack("N",pack("C*",split(/\./,$host)));
	74	my $list = $NetConfig{'local_netmask'};
	75	$list = [$list] unless ref($list);
	76	foreach (@$list) {
	77	my($net,$bits) = (m#^(\d+\.\d+\.\d+\.\d+)/(\d+)$#) or next;
	78	my $mask = ~0 << (32 - $bits);
	79	my $addr = unpack("N",pack("C*",split(/\./,$net)));
	80
	81	return 0 if (($addr & $mask) == ($quad & $mask));
	82	}
	83	return 1;
	84	}
	85
	86	return 0;
	87	}
	88
	89	use vars qw(*is_external);
	90	*is_external = \&requires_firewall;
	91
	92	1;
	93
	94	__END__
	95
	96	=head1 NAME
	97
	98	Net::Config - Local configuration data for libnet
	99
	100	=head1 SYNOPSYS
	101
	102	use Net::Config qw(%NetConfig);
	103
	104	=head1 DESCRIPTION
	105
	106	C<Net::Config> holds configuration data for the modules in the libnet
	107	distribuion. During installation you will be asked for these values.
	108
	109	The configuration data is held globally in a file in the perl installation
ea5a7fad	110	tree, but a user may override any of these values by providing their own. This
ea5a7fad	111	can be done by having a C<.libnetrc> file in their home directory. This file
406c51ee	112	should return a reference to a HASH containing the keys described below.
	113	For example
	114
	115	# .libnetrc
	116	{
	117	nntp_hosts => [ "my_prefered_host" ],
	118	ph_hosts => [ "my_ph_server" ],
	119	}
	120	__END__
	121
	122	=head1 METHODS
	123
	124	C<Net::Config> defines the following methods. They are methods as they are
	125	invoked as class methods. This is because C<Net::Config> inherits from
	126	C<Net::LocalCfg> so you can override these methods if you want.
	127
	128	=over 4
	129
	130	=item requires_firewall HOST
	131
	132	Attempts to determine if a given host is outside your firewall. Possible
	133	return values are.
	134
	135	-1 Cannot lookup hostname
	136	0 Host is inside firewall (or there is no ftp_firewall entry)
	137	1 Host is outside the firewall
	138
	139	This is done by using hostname lookup and the C<local_netmask> entry in
	140	the configuration data.
	141
	142	=back
	143
	144	=head1 NetConfig VALUES
	145
	146	=over 4
	147
	148	=item nntp_hosts
	149
	150	=item snpp_hosts
	151
	152	=item pop3_hosts
	153
	154	=item smtp_hosts
	155
	156	=item ph_hosts
	157
	158	=item daytime_hosts
	159
	160	=item time_hosts
	161
	162	Each is a reference to an array of hostnames (in order of preference),
	163	which should be used for the given protocol
	164
	165	=item inet_domain
	166
	167	Your internet domain name
	168
	169	=item ftp_firewall
	170
	171	If you have an FTP proxy firewall (B<NOT> a HTTP or SOCKS firewall)
	172	then this value should be set to the firewall hostname. If your firewall
	173	does not listen to port 21, then this value should be set to
	174	C<"hostname:port"> (eg C<"hostname:99">)
	175
686337f3	176	=item ftp_firewall_type
686337f3	177
ea5a7fad	178	There are many different ftp firewall products available. But unfortunately
ea5a7fad	179	there is no standard for how to traverse a firewall. The list below shows the
686337f3	180	sequence of commands that Net::FTP will use
	181
	182	user Username for remote host
	183	pass Password for remote host
	184	fwuser Username for firewall
	185	fwpass Password for firewall
	186	remote.host The hostname of the remote ftp server
	187
	188	=over 4
	189
	190	=item 0
	191
	192	There is no firewall
	193
	194	=item 1
	195
	196	USER user@remote.host
	197	PASS pass
	198
	199	=item 2
	200
	201	USER fwuser
	202	PASS fwpass
	203	USER user@remote.host
	204	PASS pass
	205
	206	=item 3
	207
	208	USER fwuser
	209	PASS fwpass
	210	SITE remote.site
	211	USER user
	212	PASS pass
	213
	214	=item 4
	215
	216	USER fwuser
	217	PASS fwpass
	218	OPEN remote.site
	219	USER user
	220	PASS pass
	221
	222	=item 5
	223
	224	USER user@fwuser@remote.site
	225	PASS pass@fwpass
	226
	227	=item 6
	228
	229	USER fwuser@remote.site
	230	PASS fwpass
	231	USER user
	232	PASS pass
	233
	234	=item 7
	235
	236	USER user@remote.host
	237	PASS pass
	238	AUTH fwuser
	239	RESP fwpass
	240
	241	=back
	242
406c51ee	243	=item ftp_ext_passive
	244
	245	=item ftp_int_pasive
	246
	247	FTP servers normally work on a non-passive mode. That is when you want to
	248	transfer data you have to tell the server the address and port to
	249	connect to.
	250
ea5a7fad	251	With some firewalls this does not work as the server cannot
	252	connect to your machine (because you are behind a firewall) and the firewall
	253	does not re-write the command. In this case you should set C<ftp_ext_passive>
406c51ee	254	to a I<true> value.
	255
	256	Some servers are configured to only work in passive mode. If you have
	257	one of these you can force C<Net::FTP> to always transfer in passive
ea5a7fad	258	mode; when not going via a firewall, by setting C<ftp_int_passive> to
406c51ee	259	a I<true> value.
	260
	261	=item local_netmask
	262
	263	A reference to a list of netmask strings in the form C<"134.99.4.0/24">.
	264	These are used by the C<requires_firewall> function to determine if a given
	265	host is inside or outside your firewall.
	266
	267	=back
	268
	269	The following entries are used during installation & testing on the
	270	libnet package
	271
	272	=over 4
	273
	274	=item test_hosts
	275
ea5a7fad	276	If true then C<make test> may attempt to connect to hosts given in the
406c51ee	277	configuration.
	278
	279	=item test_exists
	280
ea5a7fad	281	If true then C<Configure> will check each hostname given that it exists
406c51ee	282
	283	=back
	284
686337f3	285	=for html <hr>
	286
	287	I<$Id: //depot/libnet/Net/Config.pm#9 $>
	288
406c51ee	289	=cut