请教一下关于AES加密问题！！

AES/CFB/NoPadding

向各位大神请教一下关于，Flutter 中需要使用AES加密的问题。

1. 使用encrypt控件，
2. 传入的Key位数为16位

代码

 String encryptAes(String content, String aesKey) {
final _aesKey = Key.fromUtf8(aesKey);
final iv = IV.fromUtf8(aesKey);
final _encrypter = Encrypter(AES(_aesKey, mode: AESMode.cfb64,padding: null));
final _encrypted = _encrypter.encrypt(content, iv: iv);
return _encrypted.base64;
}

日志

======== Exception caught by gesture ===============================================================
The following ArgumentError was thrown while handling a gesture:
Invalid argument(s): Input buffer too short

When the exception was thrown, this was the stack:
#0      CFBBlockCipher._encryptBlock (package:pointycastle/block/modes/cfb.dart:120:7)
#1      CFBBlockCipher.processBlock (package:pointycastle/block/modes/cfb.dart:105:13)
#2      AES._processBlocks (package:encrypt/src/algorithms/aes.dart:65:25)
#3      AES.encrypt (package:encrypt/src/algorithms/aes.dart:37:22)
#4      Encrypter.encryptBytes (package:encrypt/src/encrypter.dart:12:19)

使用Padding后没有问题，NoPadding后会报错。
请各位大神指点，感谢了！！！！！！！！！