Shared Preferences is not secure enough to store tokens

[Hrishikesh-Bhagwat]

Issue Description: Sensitive information such as user tokens must not be stored in shared preferences. Some encryption is desirable.
Issue Severity: Medium but can be a big vulnerability
Observed Behavior: Shared preferences stores user tokens in plain text
Expected Behavior: Tokens must be stored using some encryption
Does this issue need immediate attention? Yes
Are you willing to work on this issue: Yes, I will work.

[Hrishikesh-Bhagwat]

@Sagar2366 please assign me this issue

[amul-dhungel]

Hello @Hrishikesh-Bhagwat you can use crypto package from flutter pub dev

import 'dart:convert';
import 'package:crypto/crypto.dart';

void main() {
var key = utf8.encode('token');
var bytes = utf8.encode("foobar");

var hmacSha256 = Hmac(sha256, key);
var digest = hmacSha256.convert(bytes);

print(hmacSha256);
print(digest);

}

[Hrishikesh-Bhagwat]

Hi Amul Dhungel! We can use flutter_secure_storage it uses keystore in IOS and AES in android. It will be much better according to me. Thanks for telling me about this too. Actually I have solved this on my end already. There are some conflicts in merging, trying to rectify those!

[amul-dhungel]

@Hrishikesh-Bhagwat That's great