代碼加密，也是保護網站安全的一種方法，以下我們來介紹一下如何通過PHP的自定義函數來加密我們的PHP代碼。

方法一：

<?php  
 function encode_file_contents($filename) {  
     $type=strtolower(substr(strrchr($filename,‘.‘),1));  
     if (‘php‘ == $type && is_file($filename) && is_writable($filename)) { // 如果是PHP文件 並且可寫 則進行壓縮編碼  
         $contents
 
 = file_get_contents($filename); // 判斷文件是否已經被編碼處理  
         $contents = php_strip_whitespace($filename);   
 
         // 去除PHP頭部和尾部標識  
         $headerPos = strpos($contents,‘<?php‘);  
         $footerPos = strrpos($contents,‘?>‘);  
         $contents = substr($contents, $headerPos + 5, $footerPos
 
 - $headerPos);  
         $encode = base64_encode(gzdeflate($contents)); // 開始編碼  
         $encode = ‘<?php‘."\n eval(gzinflate(base64_decode("."‘".$encode."‘".")));\n\n?>";   
 
         return file_put_contents($filename, $encode);  
     }  
     return false;  
 }   
 
 //調用函數  
 $filename = ‘dam.php‘;  
 encode_file_contents(
 
$filename);  
 echo "OK,加密完成！" 
 ?>

加密方法二：

<?php  
 
 function RandAbc($length = "") { // 返回隨機字符串  
     $str = "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz";  
     return str_shuffle($str);  
 }   
 
 $filename = ‘index.php‘; //要加密的文件  
 $T_k1 = RandAbc(); //隨機密匙1  
 $T_k2 = RandAbc(); //隨機密匙2  
 $vstr = file_get_contents($filename);  
 $v1 = base64_encode($vstr);  
 $c = strtr($v1, $T_k1, $T_k2); //根據密匙替換對應字符。  
 $c = $T_k1.$T_k2.$c;  
 $q1 = "O00O0O";  
 $q2 = "O0O000";  
 $q3 = "O0OO00";  
 $q4 = "OO0O00";  
 $q5 = "OO0000";  
 $q6 = "O00OO0";  
 $s = ‘$‘.$q6.‘=urldecode("%6E1%7A%62%2F%6D%615%5C%76%740%6928%2D%70%78%75%71%79%2A6%6C%72%6B%64%679%5F%65%68%63%73%77%6F4%2B%6637%6A");$‘.$q1.‘=$‘.$q6.‘{3}.$‘.$q6.‘{6}.$‘.$q6.‘{33}.$‘.$q6.‘{30};$‘.$q3.‘=$‘.$q6.‘{33}.$‘.$q6.‘{10}.$‘.$q6.‘{24}.$‘.$q6.‘{10}.$‘.$q6.‘{24};$‘.$q4.‘=$‘.$q3.‘{0}.$‘.$q6.‘{18}.$‘.$q6.‘{3}.$‘.$q3.‘{0}.$‘.$q3.‘{1}.$‘.$q6.‘{24};$‘.$q5.‘=$‘.$q6.‘{7}.$‘.$q6.‘{13};$‘.$q1.‘.=$‘.$q6.‘{22}.$‘.$q6.‘{36}.$‘.$q6.‘{29}.$‘.$q6.‘{26}.$‘.$q6.‘{30}.$‘.$q6.‘{32}.$‘.$q6.‘{35}.$‘.$q6.‘{26}.$‘.$q6.‘{30};eval($‘.$q1.‘("‘.base64_encode(‘$‘.$q2.‘="‘.$c.‘";eval(\‘?>\‘.$‘.$q1.‘($‘.$q3.‘($‘.$q4.‘($‘.$q2.‘,$‘.$q5.‘*2),$‘.$q4.‘($‘.$q2.‘,$‘.$q5.‘,$‘.$q5.‘),$‘.$q4.‘($‘.$q2.‘,0,$‘.$q5.‘))));‘).‘"));‘;  
 
 $s = ‘<?php ‘."\n".$s."\n".‘ ?>‘;  
 //echo $s;  
 // 生成 加密後的PHP文件  
 $fpp1 = fopen(‘temp_‘.$filename, ‘w‘);  
 fwrite($fpp1, $s) or die(‘寫文件錯誤‘);  
 
 ?>

加密方法三：

<?php  
 
 class text_auth  
 {  
     var $n_iter;  
 
     function text_auth()  
     {  
         $this->setIter(32);  
     }  
 
     function setIter($n_iter)  
     {  
         $this->n_iter = $n_iter;  
     }  
 
     function getIter()  
     {  
         return $this->n_iter;  
     }  
 
     function encrypt($data, $key)  
     {  
         $n = $this->_resize($data, 4);  
 
         $data_long[0]   = $n;  
         $n_data_long    = $this->_str2long(1, $data, $data_long);  
 
         $n = count($data_long);  
         if (($n & 1) == 1) {  
             $data_long[$n] = chr(0);  
             $n_data_long++;  
         }  
 
         $this->_resize($key, 16, true);  
         if ( ‘‘ == $key )  
             $key = ‘0000000000000000‘;  
 
         $n_key_long = $this->_str2long(0, $key, $key_long);  
 
         $enc_data   = ‘‘;  
         $w          = array(0, 0);  
         $j          = 0;  
         $k          = array(0, 0, 0, 0);  
         for ($i = 0; $i < $n_data_long; ++$i) {  
             if ($j + 4 <= $n_key_long) {  
                 $k[0] = $key_long[$j];  
                 $k[1] = $key_long[$j + 1];  
                 $k[2] = $key_long[$j + 2];  
                 $k[3] = $key_long[$j + 3];  
             } else {  
                 $k[0] = $key_long[$j % $n_key_long];  
                 $k[1] = $key_long[($j + 1) % $n_key_long];  
                 $k[2] = $key_long[($j + 2) % $n_key_long];  
                 $k[3] = $key_long[($j + 3) % $n_key_long];  
             }  
             $j = ($j + 4) % $n_key_long;  
 
             $this->_encipherLong($data_long[$i], $data_long[++$i], $w, $k);  
 
             $enc_data .= $this->_long2str($w[0]);  
             $enc_data .= $this->_long2str($w[1]);  
         }  
 
         return $enc_data;  
     }  
 
     function decrypt($enc_data, $key)  
     {  
         $n_enc_data_long = $this->_str2long(0, $enc_data, $enc_data_long);  
 
         $this->_resize($key, 16, true);  
         if ( ‘‘ == $key )  
             $key = ‘0000000000000000‘;  
 
         $n_key_long = $this->_str2long(0, $key, $key_long);  
 
         $data   = ‘‘;  
         $w      = array(0, 0);  
         $j      = 0;  
         $len    = 0;  
         $k      = array(0, 0, 0, 0);  
         $pos    = 0;  
 
         for ($i = 0; $i < $n_enc_data_long; $i += 2) {  
             if ($j + 4 <= $n_key_long) {  
                 $k[0] = $key_long[$j];  
                 $k[1] = $key_long[$j + 1];  
                 $k[2] = $key_long[$j + 2];  
                 $k[3] = $key_long[$j + 3];  
             } else {  
                 $k[0] = $key_long[$j % $n_key_long];  
                 $k[1] = $key_long[($j + 1) % $n_key_long];  
                 $k[2] = $key_long[($j + 2) % $n_key_long];  
                 $k[3] = $key_long[($j + 3) % $n_key_long];  
             }  
             $j = ($j + 4) % $n_key_long;  
 
             $this->_decipherLong($enc_data_long[$i], $enc_data_long[$i + 1], $w, $k);  
 
             if (0 == $i) {  
                 $len = $w[0];  
                 if (4 <= $len) {  
                     $data .= $this->_long2str($w[1]);  
                 } else {  
                     $data .= substr($this->_long2str($w[1]), 0, $len % 4);  
                 }  
             } else {  
                 $pos = ($i - 1) * 4;  
                 if ($pos + 4 <= $len) {  
                     $data .= $this->_long2str($w[0]);  
 
                     if ($pos + 8 <= $len) {  
                         $data .= $this->_long2str($w[1]);  
                     } elseif ($pos + 4 < $len) {  
                         $data .= substr($this->_long2str($w[1]), 0, $len % 4);  
                     }  
                 } else {  
                     $data .= substr($this->_long2str($w[0]), 0, $len % 4);  
                 }  
             }  
         }  
         return $data;  
     }  
 
     function _encipherLong($y, $z, &$w, &$k)  
     {  
         $sum    = (integer) 0;  
         $delta  = 0x9E3779B9;  
         $n      = (integer) $this->n_iter;  
 
         while ($n-- > 0) {  
             $y      = $this->_add($y,  
                                   $this->_add($z << 4 ^ $this->_rshift($z, 5), $z) ^  
                                     $this->_add($sum, $k[$sum & 3]));  
             $sum    = $this->_add($sum, $delta);  
             $z      = $this->_add($z,  
                                   $this->_add($y << 4 ^ $this->_rshift($y, 5), $y) ^  
                                     $this->_add($sum, $k[$this->_rshift($sum, 11) & 3]));  
         }  
 
         $w[0] = $y;  
         $w[1] = $z;  
     }  
 
     function _decipherLong($y, $z, &$w, &$k)  
     {  
         $sum    = 0xC6EF3720;  
         $delta  = 0x9E3779B9;  
         $n      = (integer) $this->n_iter;  
 
         while ($n-- > 0) {  
             $z      = $this->_add($z,  
                                   -($this->_add($y << 4 ^ $this->_rshift($y, 5), $y) ^  
                                         $this->_add($sum, $k[$this->_rshift($sum, 11) & 3])));  
             $sum    = $this->_add($sum, -$delta);  
             $y      = $this->_add($y,  
                                   -($this->_add($z << 4 ^ $this->_rshift($z, 5), $z) ^  
                                         $this->_add($sum, $k[$sum & 3])));  
         }  
 
         $w[0] = $y;  
         $w[1] = $z;  
     }  
 
     function _resize(&$data, $size, $nonull = false)  
     {  
         $n      = strlen($data);  
         $nmod   = $n % $size;  
         if ( 0 == $nmod )  
             $nmod = $size;  
 
         if ($nmod > 0) {  
             if ($nonull) {  
                 for ($i = $n; $i < $n - $nmod + $size; ++$i) {  
                     $data[$i] = $data[$i % $n];  
                 }  
             } else {  
                 for ($i = $n; $i < $n - $nmod + $size; ++$i) {  
                     $data[$i] = chr(0);  
                 }  
             }  
         }  
         return $n;  
     }  
 
     function _hex2bin($str)  
     {  
         $len = strlen($str);  
         return pack(‘H‘ . $len, $str);  
     }  
 
     function _str2long($start, &$data, &$data_long)  
     {  
         $n = strlen($data);  
 
         $tmp    = unpack(‘N*‘, $data);  
         $j      = $start;  
 
         foreach ($tmp as $value)  
             $data_long[$j++] = $value;  
 
         return $j;  
     }  
 
     function _long2str($l)  
     {  
         return pack(‘N‘, $l);  
     }  
 
     function _rshift($integer, $n)  
     {  
         if (0xffffffff < $integer || -0xffffffff > $integer) {  
             $integer = fmod($integer, 0xffffffff + 1);  
         }  
 
         if (0x7fffffff < $integer) {  
             $integer -= 0xffffffff + 1.0;  
         } elseif (-0x80000000 > $integer) {  
             $integer += 0xffffffff + 1.0;  
         }  
 
         if (0 > $integer) {  
             $integer &= 0x7fffffff;  
             $integer >>= $n;  
             $integer |= 1 << (31 - $n);  
         } else {  
             $integer >>= $n;  
         }  
 
         return $integer;  
     }  
 
     function _add($i1, $i2)  
     {  
         $result = 0.0;  
 
         foreach (func_get_args() as $value) {  
             if (0.0 > $value) {  
                 $value -= 1.0 + 0xffffffff;  
             }  
 
             $result += $value;  
         }  
 
         if (0xffffffff < $result || -0xffffffff > $result) {  
             $result = fmod($result, 0xffffffff + 1);  
         }  
 
         if (0x7fffffff < $result) {  
             $result -= 0xffffffff + 1.0;  
         } elseif (-0x80000000 > $result) {  
             $result += 0xffffffff + 1.0;  
         }  
         return $result;  
     }  
 }  
 ?> 
使用方法參考如下：
// 加密過程
view sourceprint?
 $text_file = S_ROOT . ‘./456.php‘;  
 $str = @file_get_contents($text_file);  
 
 require_once S_ROOT . "./text_auth.php";  
 $text_auth = new text_auth(64);  
 
 $str = $text_auth->encrypt($str, "qianyunlai.com");  
 
 $filename = S_ROOT . ‘./789.php‘; // 加密後的文本為二進制，普通的文本編輯器無法正常查看  
 file_put_contents($filename, $str); 
// 解密過程
view sourceprint
?01 $text_file = S_ROOT . ‘./789.php‘;  
 $str = @file_get_contents($text_file);  
 
 require_once S_ROOT . "./text_auth.php";  
 $text_auth = new text_auth(64);  
 
 $str = $text_auth->decrypt($str, "qianyunlai.com");  
 
 $filename = S_ROOT . ‘./456.php‘;  
 file_put_contents($filename, $str);

該方法可以對文本的內容進行 二進制加密 與 解密。

以上幾種方法各有各的優點和用處，大家也選擇使用。

php-------代碼加密的幾種方法