$ciphertext_dec = base64_decode($encrypted);
$iv = substr($this->key, 0, 16);
$decrypted = openssl_decrypt($ciphertext_dec, 'AES-256-CBC', $this->key, OPENSSL_RAW_DATA|OPENSSL_ZERO_PADDING, $iv);
打印$decrypted 是这样的： dd30a23742fd6b971 1611136039 wx7354340dfb5a098b，并不是一个xml
"3369a889d428c840\x00\x00\x011<xml><AppId><![CDATA[wx761e \n<CreateTime>1611145042</CreateTime>\n<InfoType><![CDATA t]]></InfoType>\n<ComponentVerifyTicket><![CDATA[ticket@@ p5Lc57sbe-3VTCcqtzPtXYZxIDRQV1C9tSNbwT3iu2wTXCWskc rifyTicket>\n</xml>wx761e7856cd618a26\t\t\t\t\t\t\t\t\t"不是，解密出来的
前面16个字节是随机的
然后4个字节是消息长度，用网络字节序表示
后面的才是xml
最后还带了个appid