#!/usr/bin/perl

use strict;
use warnings;
use threads;
use IO::Socket;
use IO::Select;

my $daemon = IO::Socket::INET->new (
	LocalAddr	=> '192.168.1.16',
	LocalPort	=> 8888,
	PeerAddr	=> inet_ntoa(INADDR_BROADCAST),
	PeerPort	=> 8888,
	Type		=> SOCK_STREAM,
	Proto		=> 'tcp',
	ReuseAddr	=> 1,
	Listen		=> SOMAXCONN
) or do {
	print "[ERROR]\t$@\n";
	exit 1
};

binmode $daemon;
$daemon->blocking(0);
$daemon->autoflush(1);

while (1) {
	if (my $browser = $daemon->accept) {
		binmode $browser;
		$browser->blocking(0);
		$browser->autoflush(1);
		eval {
			threads->create(\&doConnect, $browser)->detach
		};
		if ($@) {
			print "[ERROR]\t$@\n";
			exit 1
		}
	}
	select(undef, undef, undef, (int(rand(60)) ? '.001':0))
}

sub doConnect {
	my $browser = shift;
	my ($server, $ftp, $serverhost, $serverport) = '';
	binmode $browser;
	$browser->blocking(0);
	$browser->autoflush(1);
	my $select = IO::Select->new($browser);
	while (1) {
		for my $connection ($select->can_read(60)) {
			my %req = ();
			my ($uri_host, $uri_port, $crlf) = '';
			$connection->sysread(my $buffer, 65536) or goto EXIT;
			if ($connection == $browser && $buffer =~ /^\w+ +\S+ +\S+\015\012/s) {
				foreach my $pipes (split(/\015\012/, $buffer)) {
					chomp $pipes;
					$pipes =~ s/\r\n+//sg;
					$pipes =~ s/\r+|\n+//sg;
					$pipes =~ s/^\s+|\s+$//sg;
					$pipes =~ s/\f+//sg;
					$pipes =~ s/\s+|\t+/ /sg;
					unless ($req{METHOD}) {
						if ($pipes =~ /^(\w+) +(\S+) +(\S+)/s) {
							$req{METHOD} = uc $1;
							$req{URI} = $2;
							$req{PROTO} = uc $3
						}
						else {
							last
						}
					}
					elsif ($pipes =~ /^(.+)\: (.+)$/) {
						$req{HEADER_ORIG}{$1} = $2;
						$req{HEADER_SYST}{lc($1)} = $2
					}
					else {
						last
					}
				}
				if ($req{HEADER_SYST}{'content-length'}) {
					while ($buffer =~ /\015\012\015\012/g) {
						$crlf = pos $buffer;
						last
					}
				}
				my ($uri_schema, $uri_location, $uri_path, $uri_query, undef) = ($req{URI} =~ m,(?:([^:/?#]+):)?(?://([^/?#]*))?([^?#]*)(?:\?([^#]*))?(?:#(.*))?,);
				$uri_schema = lc $uri_schema;
				if ($uri_schema ne 'http' && $uri_schema ne 'https') {
					$uri_location = $uri_schema;
					if ($uri_path =~ /^\//) {
						$uri_schema = 'http'
					}
					else {
						$uri_schema = 'https';
						$uri_path = $uri_location
					}
				}
				($serverhost, $serverport) = split(':', lc $req{HEADER_SYST}{host});
				if ($serverhost eq '' && $uri_host ne '') {
					$serverhost = $uri_host;
					$serverport = $uri_port
				}
				elsif ($serverhost ne '' && $uri_host ne '' && $serverhost ne $uri_host) {
					$serverhost = $uri_host;
					$serverport = $uri_port
				}
				if (!$serverport) {
					if ($uri_schema eq 'https' || $req{METHOD} eq 'CONNECT') {
						$serverport = 443
					}
					else {
						$serverport = 80
					}
				}
				if ($serverhost eq '') {
					$serverhost = '0.0.0.0';
					$serverport = 0
				}
				my $connect_host = $serverhost;
				my $connect_port = $serverport;
				if ($req{METHOD} =~ /GET|HEAD|POST|PUT|DELETE|TRACE|OPTIONS|PATCH|CONNECT/) {
					$req{URI} = $uri_path . ($uri_query ? "?$uri_query":'');
					print "[INFO]\t" . $browser->peerhost . "\tCID:" . $browser->peerport . "\t$serverhost:$serverport $req{PROTO} $req{METHOD} $req{URI}\n";
					$server = IO::Socket::INET->new (
						PeerAddr	=> $connect_host,
						PeerPort	=> $connect_port,
						Type		=> SOCK_STREAM, 
						Proto		=> 'tcp',
						ReuseAddr	=> 1,
						Timeout		=> 60
					) or return print "[ERROR]\t$@\n";
					$browser->blocking(1);
					binmode $server;
					$server->blocking(1);
					$server->autoflush(1);
					$select->add($server);
					my $respond = '';
					if ($req{METHOD} eq 'CONNECT') {
						$respond .= "$req{PROTO} 200 Connection established\015\012\015\012";
						$connection = $server
					}
					else {
						$respond .= "$req{METHOD} $req{URI} $req{PROTO}\015\012";
						for my $list (keys %{$req{HEADER_ORIG}}) {
							next if $list =~ /^Proxy\-Authorization/i;
							if ($list =~ /Connection/i) {
								$respond .= "Connection: $req{HEADER_ORIG}{$list}\015\012"
							}
							else {
								$respond .= "$list: $req{HEADER_ORIG}{$list}\015\012"
							}
						}
						$respond .= "X-Forwarded-For: " . $browser->peerhost . "\015\012\015\012";
						if ($req{HEADER_SYST}{'content-length'}) {
							my $content = substr($buffer, $crlf || -$req{HEADER_SYST}{'content-length'});
							sysread($connection, $content, $req{HEADER_SYST}{'content-length'}) if $content eq '';
							$respond .= $content if $content ne ''
						}
					}
					$buffer = $respond
				}
			}
			($connection == $browser ? $server:$browser)->syswrite($buffer)
		}
	}
	EXIT:
	if ($browser) {
		$select->remove($browser);
		$browser->shutdown(2);
		$browser->close;
		undef $browser
	}
	if ($server) {
		$select->remove($server);
		$server->shutdown(2);
		$server->close;
		undef $server
	}
	threads->exit
}