如何使用openssl解密此字符串

Question

我在解密一个使用openssl加密的字符串时遇到了一些问题。我没有权限更改加密代码，但我确实有读取权限：

加密代码(无法修改)

<?php 
$key = hex2bin("24a5d2b96b9aee2fb515c94fb36da508");
$encryptTxt = openssl_encrypt(
    "txt to encrypt",
    'AES-128-ECB',
    $key
);
?>

<a href="decrypt.php?un=<?php echo bin2hex(base64_decode($encryptTxt)) ?>">link</a>

下面是我试图解密的方法：

decrypt.php

$ciphertext = $_GET['un'];

$cipher = "aes-128-ecb";
$key = hex2bin("24a5d2b96b9aee2fb515c94fb36da508");

$original_plaintext = openssl_decrypt($ciphertext, $cipher, $key);
echo "text= " . $original_plaintext;

解密后的文本不会返回到解密页上。

Answer 1

解决:我将decrypt.php更新为以下内容，它返回解密的文本

$ciphertext = $_GET['un'];
$ciphertext = hex2bin($ciphertext);
$ciphertext = base64_encode($ciphertext);

$cipher = "aes-128-ecb";
$key = hex2bin("24a5d2b96b9aee2fb515c94fb36da508");

$original_plaintext = openssl_decrypt($ciphertext, $cipher, $key);
echo "text= " . $original_plaintext;