How to decrypt a PHP encrypted file?

In order to decrypt an encrypted file, you need to know the encryption algorithm and key that were used. Once you have this information, you can use the corresponding decryption algorithm and key to decrypt the file.

Here is an example code using PHP to decrypt files:

<?php
function decryptFile($file, $key) {
    $encryptedData = file_get_contents($file);
    $decryptedData = openssl_decrypt($encryptedData, 'AES-256-CBC', $key, OPENSSL_RAW_DATA);
    
    return $decryptedData;
}

// 要解密的文件路径
$filePath = 'path_to_encrypted_file.txt';

// 密钥
$key = 'your_secret_key';

// 解密文件
$decryptedData = decryptFile($filePath, $key);

// 将解密后的数据写入文件
file_put_contents('path_to_decrypted_file.txt', $decryptedData);
?>

The decryptFile function in the code above takes the encrypted file path and key as parameters. It uses the openssl_decrypt function to decrypt the content of the file and returns the decrypted data. Then, it uses the file_put_contents function to write the decrypted data to a new file.

Please note that this is just an example code, and you will need to make adjustments based on the specific encryption algorithm and key you are using.