Detailed explanation of how to use OpenSSL instead of Mcrypt encryption and decryption in PHP 7.1_php tips

Recently when I was using PHP to develop the WeChat public account function, I found that Mcrypt has been deprecated in PHP 7.1. I had no choice but to find a corresponding solution to replace it, so This article mainly introduces you to the relevant information about using OpenSSL instead of Mcrypt encryption and decryption in PHP 7.1. Friends in need can refer to it.

Summary:

After the release of php7.1, the new features attracted many PHPers, and everyone is discussing what the new features will bring benefits and conveniences. However, upgrading from php7.0 to php7.1 obsolete (obsolete) an extension that was commonly used in the past (mcrypt extension). The official provides corresponding solution tips, but does not provide more detailed solutions. So here comes the trap:

Today when I used the WeChat open platform to connect to a content management system, it kept failing when binding the official account

Reason:

During debugging, we found that the direct cause is the authorization event filled in the open platform (the authorization event will send an event every ten minutes to update the ticket), that is:

The url filled in here, debugging found that this URL is correct, WeChat also pushes it every 10 minutes, but in the end the ticket cannot be received. Looking at the code, it is found that it is due to decryption When the data came over from WeChat, an error was reported:

<?php 
 
function aes_decode($message, $encodingaeskey = &#39;&#39;, $appid = &#39;&#39;) { 
 $key = base64_decode($encodingaeskey . &#39;=&#39;); 
 
 $ciphertext_dec = base64_decode($message); 
 $iv = substr($key, 0, 16); 
 
 $module = mcrypt_module_open(MCRYPT_RIJNDAEL_128, &#39;&#39;, MCRYPT_MODE_CBC, &#39;&#39;); 
 mcrypt_generic_init($module, $key, $iv); 
 $decrypted = mdecrypt_generic($module, $ciphertext_dec); 
 mcrypt_generic_deinit($module); 
 mcrypt_module_close($module); 
 
 $pad = ord(substr($decrypted, -1)); 
 if ($pad < 1 || $pad > 32) { 
 $pad = 0; 
 }

This is the place. Since my environment is PHP 7.1, I searched for information and found PHP Mcrypt has been abandoned in 7.1, so mcrypt_* in this code cannot be run.

Solution:

# Searching for information found that Mcrypt can be replaced by OpenSSL (provided that the OpenSSL extension has been installed, but generally They are all installed by default)

openssl is a powerful toolkit that integrates many cryptographic algorithms and practical tools. We can use the command console tool it provides to generate keys and certificates to encrypt and decrypt files, or we can use the API interface it provides to encrypt the transmitted information in the code.

So the above code can be changed to:

<?php 
 
function aes_decode($message, $encodingaeskey = &#39;&#39;, $appid = &#39;&#39;) { 
 $key = base64_decode($encodingaeskey . &#39;=&#39;); 
 
 $ciphertext_dec = base64_decode($message); 
 $iv = substr($key, 0, 16); 
 
 /* mcrypt对称解密代码在PHP7.1已经被抛弃了，所以使用下面的openssl来代替 
 $module = mcrypt_module_open(MCRYPT_RIJNDAEL_128, &#39;&#39;, MCRYPT_MODE_CBC, &#39;&#39;); 
 mcrypt_generic_init($module, $key, $iv); 
 $decrypted = mdecrypt_generic($module, $ciphertext_dec); 
 mcrypt_generic_deinit($module); 
 mcrypt_module_close($module); 
 */ 
 $decrypted = openssl_decrypt($ciphertext_dec, &#39;AES-256-CBC&#39;, $key, OPENSSL_RAW_DATA|OPENSSL_ZERO_PADDING, $iv); 
 
 $pad = ord(substr($decrypted, -1)); 
 if ($pad < 1 || $pad > 32) { 
 $pad = 0; 
 }

Supplement:

The above decryption has been modified, so the corresponding Mcrypt encryption also needs to be modified. If it is not changed, it will lead to events such as the inability to publish to the entire network and the inability to push messages.
The encrypted source code is as follows:

<?php 
function aes_encode($message, $encodingaeskey = &#39;&#39;, $appid = &#39;&#39;) { 
 $key = base64_decode($encodingaeskey . &#39;=&#39;); 
 $text = random(16) . pack("N", strlen($message)) . $message . $appid; 
 $iv = substr($key, 0, 16); 
 
 $block_size = 32; 
 $text_length = strlen($text); 
 $amount_to_pad = $block_size - ($text_length % $block_size); 
 if ($amount_to_pad == 0) { 
 $amount_to_pad = $block_size; 
 } 
 $pad_chr = chr($amount_to_pad); 
 $tmp = &#39;&#39;; 
 for ($index = 0; $index < $amount_to_pad; $index++) { 
 $tmp .= $pad_chr; 
 } 
 $text = $text . $tmp; 
 $size = mcrypt_get_block_size(MCRYPT_RIJNDAEL_128, MCRYPT_MODE_CBC); 
 $module = mcrypt_module_open(MCRYPT_RIJNDAEL_128, &#39;&#39;, MCRYPT_MODE_CBC, &#39;&#39;); 
 mcrypt_generic_init($module, $key, $iv); 
 $encrypted = mcrypt_generic($module, $text); 
 mcrypt_generic_deinit($module); 
 mcrypt_module_close($module); 
 
 $encrypt_msg = base64_encode($encrypted); 
 return $encrypt_msg; 
}

##The modified code is:

<?php 
function aes_encode($message, $encodingaeskey = &#39;&#39;, $appid = &#39;&#39;) { 
 $key = base64_decode($encodingaeskey . &#39;=&#39;); 
 $text = random(16) . pack("N", strlen($message)) . $message . $appid; 
 $iv = substr($key, 0, 16); 
 
 $block_size = 32; 
 $text_length = strlen($text); 
 $amount_to_pad = $block_size - ($text_length % $block_size); 
 if ($amount_to_pad == 0) { 
 $amount_to_pad = $block_size; 
 } 
 $pad_chr = chr($amount_to_pad); 
 $tmp = &#39;&#39;; 
 for ($index = 0; $index < $amount_to_pad; $index++) { 
 $tmp .= $pad_chr; 
 } 
 $text = $text . $tmp; 
 /* mcrypt对称加密代码在PHP7.1已经被抛弃了，所以使用下面的openssl来代替 
 $size = mcrypt_get_block_size(MCRYPT_RIJNDAEL_128, MCRYPT_MODE_CBC); 
 $module = mcrypt_module_open(MCRYPT_RIJNDAEL_128, &#39;&#39;, MCRYPT_MODE_CBC, &#39;&#39;); 
 mcrypt_generic_init($module, $key, $iv); 
 $encrypted = mcrypt_generic($module, $text); 
 mcrypt_generic_deinit($module); 
 mcrypt_module_close($module); 
 */ 
 
 $encrypted = openssl_encrypt($text, &#39;AES-256-CBC&#39;, $key, OPENSSL_RAW_DATA|OPENSSL_ZERO_PADDING, $iv); 
 $encrypt_msg = base64_encode($encrypted); 
 return $encrypt_msg; 
}

Special note: Any process involving WeChat development, if you have upgraded to PHP 7.1 If so, then it is necessary to check whether Mcrypt is used for symmetric encryption and decryption. The demo used in the WeChat development documentation also uses Mcrypt for encryption and decryption. This needs to be noted.

Summary

The above is all the content of this article. I hope it will be helpful to everyone in WeChat development. If you have any questions, please contact us. Ask questions in the community Q&A on this site!

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The above is the detailed content of Detailed explanation of how to use OpenSSL instead of Mcrypt encryption and decryption in PHP 7.1_php tips. For more information, please follow other related articles on the PHP Chinese website!