Search found 19 matches: re:
Searched query: re
- Thu Jan 31, 2019 5:51 am
- Forum: Algorithm School
- Topic: Is there a good way to implement an AES-CMAC encryption on Java Cards?
- Replies: 4
- Views: 24000
Re: Is there a good way to implement an AES-CMAC encryption on Java Cards?
You can implement AES-CMAC from scratch using the AES Cipher and Signature objects, and it's possible and not too difficult.
- Wed Sep 27, 2017 5:54 am
- Forum: Questions & Answers
- Topic: Sinus and Cosinus calculation in javacard?
- Replies: 5
- Views: 10465
Re: Sinus and Cosinus calculation in javacard?
To handle the angle with decimals, try to use this formula
sin(a+b) =sina*cosb+cosa*sinb
cos(a+b) = cosa*cosb - sina*sinb
Take angle 45.5 as an example,
sin(45+0.5) = sina45*cos0.5 + cos45*sin0.5
But you may need to define 4 arrays sin[0~360], cos[0~360], sin[0.0~0.1],cos[0.0~0.1]
sin(a+b) =sina*cosb+cosa*sinb
cos(a+b) = cosa*cosb - sina*sinb
Take angle 45.5 as an example,
sin(45+0.5) = sina45*cos0.5 + cos45*sin0.5
But you may need to define 4 arrays sin[0~360], cos[0~360], sin[0.0~0.1],cos[0.0~0.1]
- Wed Sep 06, 2017 10:35 pm
- Forum: Questions & Answers
- Topic: Issue about using CAC
- Replies: 1
- Views: 5480
Re: Issue about using CAC
Try to google it by typing GSC-IS keywords.
- Mon Aug 28, 2017 5:20 am
- Forum: Questions & Answers
- Topic: How to invoke a simple java card method?
- Replies: 3
- Views: 7467
Re: How to invoke a simple java card method?
You'd better carefully study the finished simple applet, e.g. wallet demo..
- Mon Aug 28, 2017 5:14 am
- Forum: Questions & Answers
- Topic: verify function cannot work
- Replies: 2
- Views: 6997
Re: verify function cannot work
It seems that the keypair you set is invalid. You do not need to set the keys manually as
actually generates a valid keypair for you.
Code: Select all
keyPair.genKeyPair();
- Thu Aug 17, 2017 6:15 am
- Forum: Open Source Applets
- Topic: Smart Card Gids Applet
- Replies: 12
- Views: 67418
Re: Smart Card Gids Applet
In my opinion, this doesn't have any problem. Because GIDS is defined based on windows framework, it's not strange that it cannot work with opensc. But I am not sure if my thought is correct.
- Mon Jul 24, 2017 11:07 pm
- Forum: Questions & Answers
- Topic: ROM applet
- Replies: 1
- Views: 5549
Re: ROM applet
You can have your applet masked into the ROM by a card manufacturer. This will remove the need for APDU's to install your applet. But you will still need to use APDU's for anything, including embedded applications on the device, to communicate with your applet. A Java Card applet is passive and does...
- Mon Mar 13, 2017 4:21 am
- Forum: Algorithm School
- Topic: Error when generating CMAC
- Replies: 1
- Views: 6725
Re: Error when generating CMAC
Your computation method has something wrong. You should notice that: the last block is DES3 encrypted, ICV is last calculated C_MAC
- Thu Feb 02, 2017 5:56 am
- Forum: Algorithm School
- Topic: Elliptic Curve Cryptography
- Replies: 1
- Views: 6654
Re: Elliptic Curve Cryptography
It's recommended to check JavaCard API document firstly.You will find the basic introduction about these. public static final byte ALG_EC_F2M: KeyPair object containing an EC key pair for EC operations over fields of characteristic 2 with polynomial basis. public static final byte ALG_EC_FP: KeyPair...
- Thu Jan 19, 2017 10:36 pm
- Forum: Algorithm School
- Topic: 3DES Key
- Replies: 2
- Views: 7681
Re: 3DES Key
If you use bouncy castle, you can use a 16 byte 2TDEA key.