Question

我正在尝试使用PHP的openssl_decrypt和openssl_encrypt在服务器上加密和解密字符串。

示例代码：

// code for encrypting the string
function encrypt($textToBeEncrypted){
    $cipher = file_get_contents('the_cipher_file', FILE_USE_INCLUDE_PATH);
    $iv     = file_get_contents('the_iv_file', FILE_USE_INCLUDE_PATH);
    $key    = file_get_contents('the_key_file', FILE_USE_INCLUDE_PATH);  
        if (in_array($cipher, openssl_get_cipher_methods())){
            $ciphertext = openssl_encrypt($textToBeEncrypted, $cipher, $key, $options=0, $iv, $tag);

            file_put_contents("the_tag_file", $tag);

            if($ciphertext){
                return $ciphertext;
            }else{
                return null;
            }
        }
        return null;
    }


// code for decrypting the string
function decrypt($textToBeDecrypted){
    $cipher = file_get_contents('the_cipher_file', FILE_USE_INCLUDE_PATH);
    $iv     = file_get_contents('the_iv_file', FILE_USE_INCLUDE_PATH);
    $key    = file_get_contents('the_key_file', FILE_USE_INCLUDE_PATH);
    $tag    = file_get_contents( "the_tag_file");   
        if (in_array($cipher, openssl_get_cipher_methods())){
            $decrypted= openssl_encrypt($textToBeDecrypted, $cipher, $key, $options=0, $iv, $tag);

            if($decrypted){
                return $decrypted;
            }else{
                return null;
            }
        }
        return null;
    }

此方法的问题在于，每次加密都会生成一个唯一的标签。例如：

$encrypted = encrypt("Hello World"); // creates tag on file "the_tag_file"
echo decrypt($encrypted); // uses tag from "the_tag_file" and decryption works fine

但是：

$encrypted_A = encrypt("Hello USA"); // creates tag A on "the_tag_file"
$encrypted_B = encrypt("Hello CANADA"); // overrides tag A on "the_tag_file" with new tag B
$encrypted_C = encrypt("Hello GERMANY"); // overrides tag B on "the_tag_file" with new tag C
echo decrypt($encrypted_A); // uses tag C instead of A and prints null
echo decrypt($encrypted_B); // uses tag C instead of B and prints null
echo decrypt($encrypted_C); // uses tag C and prints "Hello GERMANY"

因此，我的问题出现了，如何为不同的字符串维护不同的标签，即对于每次解密，我都需要在加密阶段生成的特定标签。我的目的是能够从服务器后端使用加密的字符串更新数据库内容，还可以接收加密的内容，然后在服务器后端对其进行解密，然后继续。

如何在php的openssl字符串加密方法中为多个不同的加密解密对维护标签值？

0 个答案: