解析php下载远程图片函数 可伪造来路

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(“””agif””");

复制代码 代码如下:
<?php
function DownImageKeep($gurl $rfurl $filename $gcookie="" $JumpCount= $maxtime=)
{
$urlinfos = GetHostInfo($gurl);
$ghost = trim($urlinfos[host]);
if($ghost==)
{
return FALSE;
}
$gquery = $urlinfos[query];
if($gcookie=="" && !empty($rfurl))
{
$gcookie = RefurlCookie($rfurl);
}
$sessionQuery = "GET $gquery HTTP/rn";
$sessionQuery = "Host: $ghostrn";
$sessionQuery = "Referer: $rfurlrn";
$sessionQuery = "Accept: */*rn";
$sessionQuery = "UserAgent: Mozilla/ (compatible; MSIE ; Windows )rn";
if($gcookie!="" && !preg_match("/[rn]/" $gcookie))
{
$sessionQuery = $gcookie"rn";
}
$sessionQuery = "Connection: KeepAlivernrn";
$errno = "";
$errstr = "";
$m_fp = fsockopen($ghost $errno $errstr);
fwrite($m_fp$sessionQuery);
$lnum = ;
//获取详细应答头
$m_httphead = Array();
$httpstas = explode(" "fgets($m_fp));
$m_httphead["httpedition"] = trim($httpstas[]);
$m_httphead["httpstate"] = trim($httpstas[]);
while(!feof($m_fp))
{
$line = trim(fgets($m_fp));
if($line == "" || $lnum>)
{
break;
}
$hkey = "";
$hvalue = "";
$v = ;
for($i=; $i<strlen($line); $i++)
{
if($v==)
{
$hvalue = $line[$i];
}
if($line[$i]==":")
{
$v = ;
}
if($v==)
{
$hkey = $line[$i];
}
}
$hkey = trim($hkey);
if($hkey!="")
{
$m_httphead[strtolower($hkey)] = trim($hvalue);
}
}
//分析返回记录
if(preg_match("/^/" $m_httphead["httpstate"]))
{
if(isset($m_httphead["location"]) && $JumpCount<)
{
$JumpCount++;
DownImageKeep($gurl$rfurl$filename$gcookie$JumpCount);
}
else
{
return FALSE;
}
}
if(!preg_match("/^/" $m_httphead["httpstate"]))
{
return FALSE;
}
if(!isset($m_httphead))
{
return FALSE;
}
$contentLength = $m_httphead[contentlength];
//保存文件
$fp = fopen($filename"w") or die("写入文件{$filename} 失败！");
$i=;
$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/rn";
$sessionQuery = "Host: $ghostrn";
$sessionQuery = "Accept: */*rn";
$sessionQuery = "UserAgent: Mozilla/ (compatible; MSIE ; Windows )rn";
$sessionQuery = "Connection: Closernrn";
$errno = "";
$errstr = "";
$m_fp = fsockopen($ghost $errno $errstr) or die($ghost<br />);
fwrite($m_fp$sessionQuery);
$lnum = ;
//获取详细应答头
$gcookie = "";
while(!feof($m_fp))
{
$line = trim(fgets($m_fp));
if($line == "" || $lnum>)
{
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;
}
?>