IV must be the same length as block size ( Dart )

I have a decipher method as following,

 String decipher(String fkey, String lkey, String data, String hash) {    final key = encypt.Key.fromUtf8(fkey + lkey);      var encoded = utf8.encode(data);    print([hash, hash.length]); // <-- prints  [eeee690be8c240128000815052545661, 32]    var iv = new Uint8List.fromList(utf8.encode(hash)); //utf8.encode(hash);      print(iv);      final encrypter = encypt.Encrypter(encypt.AES(key, mode: encypt.AESMode.cbc));    var encodedE = encypt.Encrypted.fromBase64(base64Encode(encoded.toList()));    var decrypted = encrypter.decrypt(encodedE,        iv: encypt.IV.fromBase64(base64Encode(iv.toList())));      return decrypted;  }  

When I run this I get an error message as,

Invalid argument(s): Initialization vector must be the same length as block size

If I try to read the IV from a text file which contains the text "eeee690be8c240128000815052545661", then its start to work.

var iv = await File("./data/iv.txt").readAsBytes(); // This works  

Both Uint8List.fromList and readAsBytes() returns Uint8List so my problem is why it is not working with var iv = new Uint8List.fromList(utf8.encode(hash)); ?

https://stackoverflow.com/questions/66828188/iv-must-be-the-same-length-as-block-size-dart March 27, 2021 at 01:07PM