OTP dummy client (enc/dec)

wipedlifepotato · February 27, 2021, 7:18am

(encrypt decrypt by a key file[with offset]) client GitHub - wipedlifepotato/OTPDUMMY: One Time Pad encryptor/Decryptor simply app android.

SkewedZeppelin · February 28, 2021, 8:44pm

github.com

wipedlifepotato/OTPDUMMY/blob/main/app/src/main/java/com/livingstonei2p/otpdummy/OTP/OTP.java#L37


      
          
              byte[] messageArray;
              if (isEncrypted) {
                  messageArray = Base64.decode(message,Base64.DEFAULT);
              }else messageArray = (byte[])message.getBytes(Charset.defaultCharset() );
              byte[] cryptedMessage = new byte[messageArray.length+1];
          
              int x;
              for(x=0;x<messageArray.length;x++){
                  byte tmp=i.readByte();
                  cryptedMessage[x]= (byte)((messageArray[x])^(tmp))  ;//0x7f?
                  assert (cryptedMessage[x]^(tmp) ) == messageArray[x];
              }
              i.close();
              this.offset = offset + x;
              if(isEncrypted) return new String(cryptedMessage, "UTF-8");
              return Base64.encodeToString(cryptedMessage, 0, cryptedMessage.length, Base64.DEFAULT);
          }
          public String doCryptDecrypt(String message) throws FileNotFoundException, IOException{
              return doCryptDecrypt(message, false);
          }

Isn’t this just a XOR cipher, that has many weaknesses and can be trivially broken?

wipedlifepotato · February 28, 2021, 9:07pm

For some guys… https://ru.m.wikipedia.org/wiki/%D0%A8%D0%B8%D1%84%D1%80_%D0%92%D0%B5%D1%80%D0%BD%D0%B0%D0%BC%D0%B0

пн, 1 мар. 2021 г., 3:54 SkewedZeppelin via F-Droid Forum <forum@f-droid.org>:

Morgoth · February 28, 2021, 9:17pm

Fixed url: One-time pad - Wikipedia

system · April 29, 2021, 9:17pm

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