Delphi - Encrypt and Decrypt with Rijndael on delphi 10.4

2022-05-04 10:17 RedDot imported from Stackoverflow

I'm trying to encrypt and decrypt with Rijndael but it always fail the encryption/decryption process.

Here is my code :

procedure TFormLicenseTest.GenKeyAndEncrypt(const Checkpwd: string; const MaxFileLimit : string)
var LbRijndael1   : TLbRijndael;
HashedMaxFile : string;
Cr            : string;
De            : string;
begin
  LbRijndael1.CipherMode := cmECB;
  LbRijndael1.KeySize    := ks256;
  HashedMaxFile          := THashMD5.GetHashString(Trim(Checkpwd));
  LbRijndael1.GenerateKey(HashedMaxFile);
  Cr := LbRijndael1.EncryptString(MaxFileLimit);
  De := LbRijndael1.DecryptString(MaxFileLimit);
end

The key is generate but the encryptionString doesn't work ...

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