php伪装来路,解析php下载远程图片函数 可伪造来路

本篇文章是对php中的下载远程图片函数进行了详细的分析介绍，需要的朋友参考下

gurl 要下载的图片地址

$rfurl 来路。如果目标图像做了防盗链设置，可以绕过。

$filename 下载图片保存的文件名，相对路径，不要用realpath

$gcookie 调整cookie 伪造的cookie

$JumpCount 跳转计数

$maxtime 最大次数

调用方法：DownImageKeep(“http://www.baidu.com/img/baidu_jgylogo2.gif”,”http://baidu.com”,”a.gif”,”",0,10);

function DownImageKeep($gurl, $rfurl, $filename, $gcookie="", $JumpCount=0, $maxtime=30)

{

$urlinfos = GetHostInfo($gurl);

$ghost = trim($urlinfos['host']);

if($ghost=='')

{

return FALSE;

}

$gquery = $urlinfos['query'];

if($gcookie=="" && !empty($rfurl))

{

$gcookie = RefurlCookie($rfurl);

}

$sessionQuery = "GET $gquery HTTP/1.1rn";

$sessionQuery .= "Host: $ghostrn";

$sessionQuery .= "Referer: $rfurlrn";

$sessionQuery .= "Accept: */*rn";

$sessionQuery .= "User-Agent: Mozilla/4.0 (compatible; MSIE 5.00; Windows 98)rn";

if($gcookie!="" && !preg_match("/[rn]/", $gcookie))

{

$sessionQuery .= $gcookie."rn";

}

$sessionQuery .= "Connection: Keep-Alivernrn";

$errno = "";

$errstr = "";

$m_fp = fsockopen($ghost, 80, $errno, $errstr,10);

fwrite($m_fp,$sessionQuery);

$lnum = 0;

//获取详细应答头

$m_httphead = Array();

$httpstas = explode(" ",fgets($m_fp,256));

$m_httphead["http-edition"] = trim($httpstas[0]);

$m_httphead["http-state"] = trim($httpstas[1]);

while(!feof($m_fp))

{

$line = trim(fgets($m_fp,256));

if($line == "" || $lnum>100)

{

break;

}

$hkey = "";

$hvalue = "";

$v = 0;

for($i=0; $i

{

if($v==1)

{

$hvalue .= $line[$i];

}

if($line[$i]==":")

{

$v = 1;

}

if($v==0)

{

$hkey .= $line[$i];

}

}

$hkey = trim($hkey);

if($hkey!="")

{

$m_httphead[strtolower($hkey)] = trim($hvalue);

}

}

//分析返回记录

if(preg_match("/^3/", $m_httphead["http-state"]))

{

if(isset($m_httphead["location"]) && $JumpCount<3)

{

$JumpCount++;

DownImageKeep($gurl,$rfurl,$filename,$gcookie,$JumpCount);

}

else

{

return FALSE;

}

}

if(!preg_match("/^2/", $m_httphead["http-state"]))

{

return FALSE;

}

if(!isset($m_httphead))

{

return FALSE;

}

$contentLength = $m_httphead['content-length'];

//保存文件

$fp = fopen($filename,"w") or die("写入文件：{$filename} 失败！");

$i=0;

$okdata = "";

$starttime = time();

while(!feof($m_fp))

{

$okdata .= fgetc($m_fp);

$i++;

//超时结束

if(time()-$starttime>$maxtime)

{

break;

}

//到达指定大小结束

if($i >= $contentLength)

{

break;

}

}

if($okdata!="")

{

fwrite($fp,$okdata);

}

fclose($fp);

if($okdata=="")

{

@unlink($filename);

fclose($m_fp);

return FALSE;

}

fclose($m_fp);

return TRUE;

}

/**

*  获得某页面返回的Cookie信息

*

* @access    public

* @param     string  $gurl  调整地址

* @return    string

*/

function RefurlCookie($gurl)

{

global $gcookie,$lastRfurl;

$gurl = trim($gurl);

if(!empty($gcookie) && $lastRfurl==$gurl)

{

return $gcookie;

}

else

{

$lastRfurl=$gurl;

}

if(trim($gurl)=='')

{

return '';

}

$urlinfos = GetHostInfo($gurl);

$ghost = $urlinfos['host'];

$gquery = $urlinfos['query'];

$sessionQuery = "GET $gquery HTTP/1.1rn";

$sessionQuery .= "Host: $ghostrn";

$sessionQuery .= "Accept: */*rn";

$sessionQuery .= "User-Agent: Mozilla/4.0 (compatible; MSIE 5.00; Windows 98)rn";

$sessionQuery .= "Connection: Closernrn";

$errno = "";

$errstr = "";

$m_fp = fsockopen($ghost, 80, $errno, $errstr,10) or die($ghost.'
');

fwrite($m_fp,$sessionQuery);

$lnum = 0;

//获取详细应答头

$gcookie = "";

while(!feof($m_fp))

{

$line = trim(fgets($m_fp,256));

if($line == "" || $lnum>100)

{

break;

}

else

{

if(preg_match("/^cookie/i", $line))

{

$gcookie = $line;

break;

}

}

}

fclose($m_fp);

return $gcookie;

}

/**

*  获得网址的host和query部份

*

* @access    public

* @param     string  $gurl  调整地址

* @return    string

*/

function GetHostInfo($gurl)

{

$gurl = preg_replace("/^http:///i", "", trim($gurl));

$garr['host'] = preg_replace("//(.*)$/i", "", $gurl);

$garr['query'] = "/".preg_replace("/^([^/]*)//i", "", $gurl);

return $garr;

}

?>