Perl实现的Linux下socket代理服务器

大家提供了许多linux开代理的方法，一般用到python等语言，一些服务器可能不会安装，然而perl可以说是linux标配的语言，给大家一款Perl语言的socket代理，代码非常少，而且还支持密码，效果还是不错，感觉很稳定。

#!/usr/bin/perl 

$auth_enabled = 0;
$auth_login = "hidden";
$auth_pass = "hidden";
$port = 44269; 

use IO::Socket::INET; 

$SIG{'CHLD'} = 'IGNORE';
$bind = IO::Socket::INET->new(Listen=>10, Reuse=>1, LocalPort=>$port) or die "Нельзя забиндить порт $port\n"; 

while($client = $bind->accept()) {
$client->autoflush(); 

if(fork()){ $client->close(); }
else { $bind->close(); new_client($client); exit(); }
} 

sub new_client {
local $t, $i, $buff, $ord, $success;
local $client = $_[0];
sysread($client, $buff, 1); 

if(ord($buff) == 5) {
 sysread($client, $buff, 1);
 $t = ord($buff); 

 unless(sysread($client, $buff, $t) == $t) { return; } 

 $success = 0;
 for($i = 0; $i < $t; $i++) {
 $ord = ord(substr($buff, $i, 1));
 if($ord == 0 && !$auth_enabled) {
  syswrite($client, "\x05\x00", 2);
  $success++;
  break;
 }
 elsif($ord == 2 && $auth_enabled) {
  unless(do_auth($client)){ return; }
  $success++;
  break;
 }
 } 

 if($success) {
 $t = sysread($client, $buff, 3); 

 if(substr($buff, 0, 1) == '\x05') {
  if(ord(substr($buff, 2, 1)) == 0) {
  ($host, $raw_host) = socks_get_host($client);
  if(!$host) { return; }
  ($port, $raw_port) = socks_get_port($client);
  if(!$port) { return; }
  $ord = ord(substr($buff, 1, 1));
  $buff = "\x05\x00\x00".$raw_host.$raw_port;
  syswrite($client, $buff, length($buff));
  socks_do($ord, $client, $host, $port);
  }
 }
 } else { syswrite($client, "\x05\xFF", 2); };
}
$client->close();
} 

sub do_auth {
local $buff, $login, $pass;
local $client = $_[0]; 

syswrite($client, "\x05\x02", 2);
sysread($client, $buff, 1); 

if(ord($buff) == 1) {
 sysread($client, $buff, 1);
 sysread($client, $login, ord($buff));
 sysread($client, $buff, 1);
 sysread($client, $pass, ord($buff)); 

 if($login eq $auth_login && $pass eq $auth_pass) {
 syswrite($client, "\x05\x00", 2);
 return 1;
 } else { syswrite($client, "\x05\x01", 2); }
} 

$client->close();
return 0;
} 

sub socks_get_host {
local $client = $_[0];
local $t, $ord, $raw_host;
local $host = ""; 

sysread($client, $t, 1);
$ord = ord($t);
if($ord == 1) {
 sysread($client, $raw_host, 4);
 @host = $raw_host =~ /(.)/g;
 $host = ord($host[0]).".".ord($host[1]).".".ord($host[2]).".".ord($host[3]);
} elsif($ord == 3) {
 sysread($client, $raw_host, 1);
 sysread($client, $host, ord($raw_host));
 $raw_host .= $host;
} elsif($ord == 4) {
 #ipv6 - not supported
} 

return ($host, $t.$raw_host);
} 

sub socks_get_port {
local $client = $_[0];
local $raw_port, $port;
sysread($client, $raw_port, 2);
$port = ord(substr($raw_port, 0, 1)) << 8 | ord(substr($raw_port, 1, 1));
return ($port, $raw_port);
} 

sub socks_do {
local($t, $client, $host, $port) = @_; 

if($t == 1) { socks_connect($client, $host, $port); }
elsif($t == 2) { socks_bind($client, $host, $port); }
elsif($t == 3) { socks_udp_associate($client, $host, $port); }
else { return 0; } 

return 1;
} 

sub socks_connect {
my($client, $host, $port) = @_;
my $target = IO::Socket::INET->new(PeerAddr => $host, PeerPort => $port, Proto => 'tcp', Type => SOCK_STREAM); 

unless($target) { return; } 

$target->autoflush();
while($client || $target) {
 my $rin = "";
 vec($rin, fileno($client), 1) = 1 if $client;
 vec($rin, fileno($target), 1) = 1 if $target;
 my($rout, $eout);
 select($rout = $rin, undef, $eout = $rin, 120);
 if (!$rout && !$eout) { return; }
 my $cbuffer = "";
 my $tbuffer = ""; 

 if ($client && (vec($eout, fileno($client), 1) || vec($rout, fileno($client), 1))) {
 my $result = sysread($client, $tbuffer, 1024);
 if (!defined($result) || !$result) { return; }
 } 

 if ($target && (vec($eout, fileno($target), 1) || vec($rout, fileno($target), 1))) {
 my $result = sysread($target, $cbuffer, 1024);
 if (!defined($result) || !$result) { return; }
 } 

 if ($fh && $tbuffer) { print $fh $tbuffer; } 

 while (my $len = length($tbuffer)) {
 my $res = syswrite($target, $tbuffer, $len);
 if ($res > 0) { $tbuffer = substr($tbuffer, $res); } else { return; }
 } 

 while (my $len = length($cbuffer)) {
 my $res = syswrite($client, $cbuffer, $len);
 if ($res > 0) { $cbuffer = substr($cbuffer, $res); } else { return; }
 }
}
} 

sub socks_bind {
my($client, $host, $port) = @_;
} 

sub socks_udp_associate {
my($client, $host, $port) = @_;
}