Our Online Store have the new products: RFID antenna board. Currently it can work with JC10M24R and JCOP4 card chips.
Compared with normal cards, the antenna board module has a smaller size and fixed holes, which is easy to integrate in the IOT(Internet Of Things) project.

Difference between KeyBuilder and KeyPair

Algorithm School

Moderator: UNKNwYSHSA

Vlidda
Posts: 16
Joined: Tue Sep 06, 2016 2:59 am
Points :196
Contact:

Difference between KeyBuilder and KeyPair

Post by Vlidda » Wed Apr 26, 2017 3:17 am

I have doubts about key generation when writing my java card applet. I wonder the difference between KeyBuilder and KeyPair and also the difference between buildKey and KeyPair as well.
And what type of memory is used by the genKeyPair() method, Transient or Persistent ? Many thanks for any help.

chico0609
Posts: 59
Joined: Mon Sep 14, 2015 5:05 am
Points :416
Contact:

Re: Difference between KeyBuilder and KeyPair

Post by chico0609 » Wed Apr 26, 2017 6:00 am

buildKey is not used to generate a key.

And what type of memory is used by the genKeyPair() method, Transient or Persistent ?


From my understanding, it is common for a smart cards to have RAM dedicated to cryptographic operations. In fact, as much of the operation as possible is done in transient RAM. For key objects, you can specify where the key material is stored. This is specified when you create the key object.

Vlidda
Posts: 16
Joined: Tue Sep 06, 2016 2:59 am
Points :196
Contact:

Re: Difference between KeyBuilder and KeyPair

Post by Vlidda » Wed Apr 26, 2017 11:15 pm

I used new state to generate RSA keypair object, does it mean that the key objects will be stored in persistent memory?

Code: Select all

KeyPair RSA_KEYP= new KeyPair(KeyPair.ALG_RSA_CRT, (short)1024);
RSA_KEYP.genKeyPair();
rsa_PublicKey = (RSAPublicKey)RSA_KEYP.getPublic();
rsa_PrivateKey=(RSAPrivateCrtKey)RSA_KEYP.getPrivate();               

chico0609
Posts: 59
Joined: Mon Sep 14, 2015 5:05 am
Points :416
Contact:

Re: Difference between KeyBuilder and KeyPair

Post by chico0609 » Thu Apr 27, 2017 4:12 am

Yes, if you use new statement, the key objects will be stored in persistent memory.

You just need to write once and then you can read many times.

Post Reply Previous topicNext topic

Who is online

Users browsing this forum: No registered users and 21 guests

JavaCard OS : Disclaimer