preg_match not matching

[Master_script_maker]

i'm developing a proxy server for a client that he will put all of his workers through, for internet, so i have to parse everything. The only thing i have a problem with is forms. This is my code

$pageData = preg_replace('/(<form(.*)action="(.*)"(.*)>)(.*)/', '$1<input type="hidden" name="ac_url" value="$3" />$5', $pageData); 

for some reason this is not working. any help would be much appreciated.
thanks

[Master_script_maker]

does anyone have some help

[Jas]

For one thing, it is set to greedy. You can place a u outside of the pattern, or follow every .* with a ?.

.* = go as far as you can
.*?= stop as soon as you can

Another thing, you might need to be more specific. For example, something like [^>]*? tells it to find everything that is not a > (and the ? tells it to stop at the first >).

[jackbenimble4]

Whenever I write a regular expression that isn't matching, I break it down and rebuild it slowly piece by piece.

Writing proxies can be a total b!tch. I made a stab at one for fun once, and it worked well enough that it let me pass through a Webwasher filter and browse blocked sites. I remember it had a few problems I gave up on because I really had no reason to further develop it. If you'd like to take a look, here's the crude class I used:

<?php

// A proxy class for creating a proxy to bypass a filter 


class jproxy {
    protected $proxyBaseUrl = NULL;
    protected $currentUrl = NULL;
    protected $pageDomain = NULL;
    protected $fullContentType = NULL;
    protected $contentType = NULL;
    protected $html = NULL;
    
    function __construct($baseUrl) {
        $this->setBaseUrl($baseUrl);
    }
    
    function setBaseUrl($url) {
        $this->proxyBaseUrl = $url;
    }

    function setUrl($url) {
        $this->currentUrl = $url;
    }

    function getUrl() {
        return $this->currentUrl;
    }

    function fetchHtml() {
        if(!$this->getUrl()) {
            // no url to grab html for
            return false;
        }

        // 
        $ch = curl_init();
        curl_setopt($ch, CURLOPT_RETURNTRANSFER, 1);
        curl_setopt($ch, CURLOPT_TIMEOUT, 4);
        curl_setopt($ch, CURLOPT_URL, $this->getUrl());
        curl_setopt($ch, CURLOPT_FOLLOWLOCATION, true);
        curl_setopt($ch, CURLOPT_COOKIESESSION, true);
        curl_setopt($ch, CURLOPT_COOKIEJAR, $GLOBALS['cookieFile']);
        curl_setopt($ch, CURLOPT_COOKIEFILE, $GLOBALS['cookieFile']);
        curl_setopt($ch, CURLOPT_USERAGENT, $_SERVER['HTTP_USER_AGENT']);

        
        if($_POST) {
            $count = 1;
            foreach($_POST as $key => $val) {
                $headers .= $key.'='.$val;
                if($count != count($_POST)) {
                    $headers .= "&";
                }
                $count++;
            }
            curl_setopt($ch, CURLOPT_POST, 1);
            curl_setopt($ch, CURLOPT_POSTFIELDS, $headers);
        }
        
        /*foreach($_GET as $key => $val) {
            if($key != 'url') {
                echo $key . " => " . $val . "<br />";
            }
        }*/
        
        
        
        $this->html = curl_exec($ch);
        
        $this->fullContentType = curl_getinfo($ch, CURLINFO_CONTENT_TYPE);
        preg_match( '@([\w/+]+)(;\s+charset=(\S+))?@i', $this->fullContentType, $matches );
        
        if(isset($matches[1])) {
            $this->contentType = $matches[1];
        }
        
        
        curl_close($ch);
    }
    
    
    function getDomain() {
        if($this->pageDomain) {
            return $this->pageDomain;
        }
        else {
            preg_match('/http:\/\/(www\.)?([^\/]+)/', $this->currentUrl, $matches);
            return "http://".$matches[2]."/";
        }
    }
    
    protected function modifyHref($url) {
        // is a css or favicon file?
        if(stripos($url, '.css') || stripos($url, 'style.php') || strpos($url, 'favicon.ico')) {
            if(substr($url, 0, 7) == 'http://') {
                $new = "href=\"".$this->proxyBaseUrl."?url=".$url."\"";
            }
            else {
                $new = "href=\"".$this->proxyBaseUrl."?url=".$this->getDomain().$url."\"";
            }
        }
        else {
            if(substr($url, 0, 7) == 'http://') {
                $new = "href=\"".$this->proxyBaseUrl."?url=".$url."\"";
            } else {
                $new = "href=\"".$this->proxyBaseUrl."?url=".$this->getDomain().$url."\"";
            }
        }
        
        //$new = str_replace('//','/',$new);
        
        return $new;
    }
    
    protected function modifySrc($text) {
        if(substr($text, 0, 7) == 'http://') {
            $new = "src=\"".$this->proxyBaseUrl."?url=".$text."\"";
        } else {
            $new = "src=\"".$this->proxyBaseUrl."?url=".$this->getDomain()."/".$text."\"";
        }
        
        //$new = str_replace('//','/',$new);
        
        return $new;
        
    }
    
    protected function modifyActions($text) {
        if(substr($text, 0, 7) == 'http://')
        {
            $new = "action=\"".$this->proxyBaseUrl."?url=".$text."\"";
        }
        else
        {
            $new = "action=\"".$this->proxyBaseUrl."?url=".$this->getDomain().$text."\"";
        }
        
        //$new = str_replace('//','/',$new);
        return $new;
    }
    
    protected function modifyFlash($text) {
        if(substr($text, 0, 7) == 'http://') {
            $new = "<param value=\"".$this->proxyBaseUrl."?url=".$text."\"";
        }
        else {
            "<param value=\"?url=".$this->proxyBaseUrl."?url=".$this->getDomain().$text."\"";
        }   
        //$new = str_replace("//","/", $new);
        
        return $new;
    }

    protected function getExtension() {
        preg_match('/\.([^.]+)$/', $this->currentUrl, $matches);
        return $matches[0];
    }

    protected function stripShit() {
        $return = str_replace('/','',$this->currentUrl);
        $return = str_replace(':','',$return);
        $return = str_replace('.','',$return);
        return $return;
    }
    
    protected function modifyForm($whole, $formAttr, $content) {
        $content = '\n\n<!--INSERTED FORM ELEMENT BY PROXY -->\n';
        $content .= '<input type=\"hidden\" name=\"url_204s52bg\" value=\"\" />';
        $whole = str_replace($content, $myForm.$content, $whole);
        return $whole;
    }
    
    protected function modifyInlineStyles($props,$content) {
        $content = $this->modifyCssLocations($content);
        return "<style".$props.">".$content."</style>";
    }
    
    protected function modifyLocations() {
        // replace href (links, stylesheets, etc.)
        $this->html = preg_replace('/href=(\'|")(.+?)\1/ie', '$this->modifyHref("$2")', $this->html);
        
        // replace src (images, etc.)
        $this->html = preg_replace('/src=(\'|")(.+?)\1/ie', '$this->modifySrc("$2")', $this->html);
        
        // replace form actions
        $this->html = preg_replace('/action=("|\')(.+?)\1/ie', '$this->modifyActions("$2")', $this->html);
        
        // add form url thing
        //$this->html = preg_replace('/(<form(.?)>(.?)<\/form>)/', '$this->modifyForm("$1","$2","$3")', $this->hrml);
        
        // replace flash paths
        $this->html = preg_replace('/<param value=("|\')(.+?)\1/ie', '$this->modifyFlash("$2")', $this->html);
        
        // replace any @imports in inline stylesheets
        $this->html = preg_replace('/<style([^>]*)>(.+?)<\/style>/ie', '$this->modifyInlineStyles("$1","$2")', $this->html);
        
        $this->html = stripslashes($this->html);
    }
    
    private function modifyCssUrl($url) {
    
        if(substr($url, 0, 7) == 'http://') {
            $return = $this->proxyBaseUrl.'?url='.$url;
        }
        else {
            $return = $this->proxyBaseUrl.'?url='.$this->getDomain().$url;
        }
        
        return 'url('.$return.')';
    }
    
    private function modifyCssImport($file) {
        if(substr($url, 0, 7) == 'http://') {
            $return = $this->proxyBaseUrl.'?url='.$file;
        }
        else {
            $return = $this->proxyBaseUrl.'?url='.$this->getDomain().$file;
        }
        
        return '@import "'.$return.'";';
    }
    
    private function modifyCssLocations($content) {
        $content = preg_replace('/url\((.+?)\)/ie', '$this->modifyCssUrl("$1")', $content);
        
        // replace imports
        $content = preg_replace('/@import(|\s)(\'|")(.+?)\2;/ie','$this->modifyCssImport("$3")', $content);
        
        return $content;
    }

    function getHtml() {
        return $this->html;
    }
    
    function getFormattedPage() {
        
        if(
        ($this->contentType != NULL) && (stripos($this->contentType,'text/html') === false || stripos($this->contentType,'application/xhtml') != false)
        ) {
            header("Content-Type: ".$this->fullContentType);
            if(stripos($this->contentType,'css')) {
                // css file, modify that *****
                $this->html = $this->modifyCssLocations($this->html);
            }
        }
        else {
            // we only want to modify locations if it's a regular old webpage
            $this->modifyLocations();
        }

        //$this->modifyLocations();
        
        return $this->html;
    }

}

?>

And I used the class like so:

<?php


if(!$_COOKIE['proxSession']) {
    // set the cookie
    setcookie('proxSession', md5('prox'.microtime().$_SERVER['HTTP_USER_AGENT']), time()+60*20, '/', '.example.com');
}
else {
    // rewnew the time for the cookie
    setcookie('proxSession', $_COOKIE['proxSession'], time()+60*20,
    '/', '.example.com');
}

$cookieFile = "cook_".$_COOKIE['proxSession'];

// get the class
require_once('jproxy.class.php');


if($_GET['url']) {
    $p = new jproxy("http://www.example.com/page.php");
    $p->setUrl($_GET['url']);
    $p->fetchHtml();

    print $p->getFormattedPage();
}

?>

Looking back at the class, it looks like I used this regular expression to match forms:

// replace form actions
$this->html = preg_replace('/action=("|\')(.+?)\1/ie', '$this->modifyActions("$2")', $this->html); 

Which used the function:

    protected function modifyActions($text) {
        if(substr($text, 0, 7) == 'http://')
        {
            $new = "action=\"".$this->proxyBaseUrl."?url=".$text."\"";
        }
        else
        {
            $new = "action=\"".$this->proxyBaseUrl."?url=".$this->getDomain().$text."\"";
        }
        
        //$new = str_replace('//','/',$new);
        return $new;
    } 

I hope some of that was some help. Sorry I couldn't help with your expression, but I don't have time to break it down and test it.

[Master_script_maker]

thanks guys. i didn't find the problem, but rewrote and it worked fine.