- Posts: 9
- Joined: Wed Dec 21, 2016 11:46 pm
- Points :82
I have to use DES alg in my applet. But the length of Data are 132 bytes. So I wonder if it's feasible to implement DES encryption with data length 132 byte?
Code: Select all
skey = (DESKey) KeyBuilder.buildKey(KeyBuilder.TYPE_DES,KeyBuilder.LENGTH_DES3_2KEY, false);
cDES = Cipher.getInstance(Cipher.ALG_DES_CBC_ISO9797_M2, false);
cDES.doFinal(Data, doffset, dlen, EBuffer, eoffset); // Data and EBuffer are 132 byte length
- Posts: 237
- Joined: Mon May 18, 2015 3:09 am
- Points :1697
DES requires the data to be block-aligned to an 8 byte boundary. You can have different length input as long as the cipher instance pads the data. Then the output would be block-aligned.
- Posts: 7
- Joined: Thu Feb 25, 2016 3:48 am
- Points :74
Under javacard implementation, the padding is done transparently so it can be block-aligned automatically. You don't need to worry about data length.
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