Skip to content

HTTPS clone URL

Subversion checkout URL

You can clone with
or
.
Download ZIP
branch: master
Fetching contributors…

Cannot retrieve contributors at this time

executable file 123 lines (98 sloc) 2.804 kb
#!/usr/bin/perl
#
# Peteris Krumins (peter@catonmat.net)
# http://www.catonmat.net -- good coders code, great reuse
#
#
# Written for the article "A TCP Proxy in Perl":
#
# http://catonmat.net/blog/perl-tcp-proxy
#
use warnings;
use strict;
use IO::Socket::INET;
use IO::Select;
my @allowed_ips = ('all', '10.10.10.5');
my $ioset = IO::Select->new;
my %socket_map;
my $debug = 1;
sub new_conn {
my ($host, $port) = @_;
return IO::Socket::INET->new(
PeerAddr => $host,
PeerPort => $port
) || die "Unable to connect to $host:$port: $!";
}
sub new_server {
my ($host, $port) = @_;
my $server = IO::Socket::INET->new(
LocalAddr => $host,
LocalPort => $port,
ReuseAddr => 1,
Listen => 100
) || die "Unable to listen on $host:$port: $!";
}
sub new_connection {
my $server = shift;
my $remote_host = shift;
my $remote_port = shift;
my $client = $server->accept;
my $client_ip = client_ip($client);
unless (client_allowed($client)) {
print "Connection from $client_ip denied.\n" if $debug;
$client->close;
return;
}
print "Connection from $client_ip accepted.\n" if $debug;
my $remote = new_conn($remote_host, $remote_port);
$ioset->add($client);
$ioset->add($remote);
$socket_map{$client} = $remote;
$socket_map{$remote} = $client;
}
sub close_connection {
my $client = shift;
my $client_ip = client_ip($client);
my $remote = $socket_map{$client};
$ioset->remove($client);
$ioset->remove($remote);
delete $socket_map{$client};
delete $socket_map{$remote};
$client->close;
$remote->close;
print "Connection from $client_ip closed.\n" if $debug;
}
sub client_ip {
my $client = shift;
return inet_ntoa($client->sockaddr);
}
sub client_allowed {
my $client = shift;
my $client_ip = client_ip($client);
return grep { $_ eq $client_ip || $_ eq 'all' } @allowed_ips;
}
die "Usage: $0 <local port> <remote_host:remote_port>" unless @ARGV == 2;
my $local_port = shift;
my ($remote_host, $remote_port) = split ':', shift();
print "Starting a server on 0.0.0.0:$local_port\n";
my $server = new_server('0.0.0.0', $local_port);
$ioset->add($server);
while (1) {
for my $socket ($ioset->can_read) {
if ($socket == $server) {
new_connection($server, $remote_host, $remote_port);
}
else {
next unless exists $socket_map{$socket};
my $remote = $socket_map{$socket};
my $buffer;
my $read = $socket->sysread($buffer, 4096);
if ($read) {
$remote->syswrite($buffer);
}
else {
close_connection($socket);
}
}
}
}
Jump to Line
Something went wrong with that request. Please try again.