PHP code for detecting image Trojans (multiple programming)

This article shares a piece of code for detecting picture Trojans implemented in PHP, which can be used to detect hexadecimal encoding Trojans. Friends in need can refer to it.

This PHP program detects picture Trojans and analyzes Trojan programs from the production principle. Some Trojan programs are written in hexadecimal encoding, so it takes some effort to detect them, so this PHP Trojan detection class was implemented.

Code:

<?php 
/** 
* Upload 文件上传类
* 用于检测木马文件
*/ 
class Upload { 
private static $image = null; 
private static $status = 0; 
private static $suffix = null; 
private static $imageType = array('.jpg', '.bmp','.gif','.png'); 
private static $message = array( 
'0' => '没有错误发生，文件上传成功。', 
'1' => '上传的文件超过了 php.ini 中 upload_max_filesize 选项限制的值。', 
'2' => '上传文件的大小超过了 HTML 表单中 MAX_FILE_SIZE 选项指定的值。', 
'3' => '文件只有部分被上传。', 
'4' => '没有文件上传。', 
'5' => '未能通过安全检查的文件。', 
'6' => '找不到临时文件夹。', 
'7' => '文件写入失败。', 
'8' => '文件类型不支持', 
'9' => '上传的临时文件丢失。', 
); 
//@ 开始执行文件上传 
public static function start($feild = 'file') { 
if (!empty($_FILES)) { 
self::$status = $_FILES[$feild]['error']; 
if (self::$status > 0) 
return array('status' => self::$status, 'msg' => self::$message[self::$status]); 
self::$image = $_FILES[$feild]['tmp_name']; 
self::$suffix = strtolower(strrchr($_FILES[$feild]['name'], '.')); 
return array('status' => self::_upload(), 'path' => self::$image, 'msg' => self::$message[self::$status]); 
} else { 
return array('status' => self::$status, 'msg' => self::$message[self::$status]); 
} 
} 
//@ 私有 上传开始 
private static function _upload($path = './upload/') { 
date_default_timezone_set('PRC'); 
$newFile = $path . date('Y/m/d/His') . rand(100, 999) . self::$suffix; 
self::umkdir(dirname($newFile)); 
if (is_uploaded_file(self::$image) && move_uploaded_file(self::$image, $newFile)) { 
self::$image = $newFile; 
if (in_array(self::$suffix, self::$imageType)) 
return self::checkHex(); 
else 
return self::$status = 0; 
} else { 
return self::$status = 9; 
} 
} 
//@ 私有 16进制检测 
private static function checkHex() { 
if (file_exists(self::$image)) { 
$resource = fopen(self::$image, 'rb'); 
$fileSize = filesize(self::$image); 
fseek($resource, 0); 
if ($fileSize > 512) { // 取头和尾 
$hexCode = bin2hex(fread($resource, 512)); 
fseek($resource, $fileSize - 512); 
$hexCode .= bin2hex(fread($resource, 512)); 
} else { // 取全部 
$hexCode = bin2hex(fread($resource, $fileSize)); 
} 
fclose($resource); 
/* 匹配16进制中的 <% ( ) %> */ 
/* 匹配16进制中的 <? ( ) ?> */ 
/* 匹配16进制中的 <script | /script> 大小写亦可*/ 
if (preg_match("/(3c25.*?28.*?29.*?253e)|(3c3f.*?28.*?29.*?3f3e)|(3C534352495054)|(2F5343524950543E)|(3C736372697074)|
(2F7363726970743E)/is", $hexCode)) 
self::$status = 5; 
else 
self::$status = 0; 
return self::$status; 
} else { 
return self::$status = 9; 
} 
} 
//@ 私有 创建目录 
private static function umkdir($dir) { 
if (!file_exists($dir) && !is_dir($dir)) { 
self::umkdir(dirname($dir)); 
@mkdir($dir); 
} 
} 
}