A User Centric Security Model for Tamper-Resistant Devices

C.8 Application Binding Protocol - Distributed
437 void d h I n i t i a l i s a t i o n ( ) {
438 dhKey . setModulus ( ClassDH . dhModulus , ( short ) 0 ,
( short ) ClassDH . dhModulus . l e n g t h ) ;
439 }
440 void dhKeyConGen(byte [ ] i n b u f f , short i n b u f f O f f s e t , byte Oper_Mode)
441 {
442 switch (Oper_Mode) {
443 case GEN_KEYCONTRIBUTION: randomExponent =
444 JCSystem . makeTransientByteArray ( ( short ) 32 ,
445 JCSystem .MEMORY_TYPE_TRANSIENT_DESELECT) ;
446 randomDataGen . generateData ( randomExponent , ( short ) 0 , ( short )
447 randomExponent . l e n g t h ) ;
448 dhKey . setExponent ( randomExponent , ( short ) 0 , ( short )
449 randomExponent . l e n g t h ) ;
450 pkCipher . i n i t ( dhKey , Cipher .MODE_ENCRYPT) ;
451 pkCipher . doFinal ( ClassDH . dhBase , ( short ) 0 ,
( short ) ClassDH . dhBase . length , i n b u f f ,
452 i n b u f f O f f s e t ) ;
453 break ;
454 case GEN_DHKEY:
455 try {
456 dhKey . setExponent ( randomExponent , ( short ) 0 , ( short )
457 randomExponent . l e n g t h ) ;
458 pkCipher . i n i t ( dhKey , Cipher .MODE_ENCRYPT) ;
459 ServerAppClientAppDHGeneratedValue =
JCSystem . makeTransientByteArray (
460 ( short ) ClassDH . dhModulus . length ,
461 JCSystem .MEMORY_TYPE_TRANSIENT_DESELECT) ;
462 pkCipher . doFinal ( i n b u f f , i n b u f f O f f s e t , ( short ) ( ( short )
463 i n b u f f . l e n g t h − ( short ) this . PTLVDataOffset )
464 , ServerAppClientAppDHGeneratedValue ,
( short ) 0) ;
465 }
466 catch ( Exception cE ) {
467 ISOException . throwIt ( ( short ) 0xD86E) ;
468 }
469 break ;
470 default :
471 ISOException . throwIt ( ( short ) 0x5FA1) ;
472 }
473 }
474 void keygenerator ( ) {
475 AESKey sessionGenKey = (AESKey) KeyBuilder . buildKey
476 ( KeyBuilder .TYPE_AES_TRANSIENT_DESELECT,
477 KeyBuilder .LENGTH_AES_128, f a l s e ) ;
478 sessionGenKey . setKey ( ServerAppClientAppDHGeneratedValue , ( short ) 0) ;
479 phMacGenerator . i n i t ( sessionGenKey , S i g n a t u r e .MODE_SIGN,
480 I n i t i a l i s a t i o n V e c t o r , ( short ) 0 , ( short )
481 I n i t i a l i s a t i o n V e c t o r . l e n g t h ) ;
482 byte [ ] keyGenMacData = JCSystem . makeTransientByteArray ( ( short ) 64 ,
483 JCSystem .MEMORY_TYPE_TRANSIENT_DESELECT) ;
401