| Transactions and non-atomic API methods in Java Card: specification ambiguity and strange implementation behaviours (2008) | |||||||||||||||
Abstract | |||||||||||||||
| Abstract. This paper discusses an ambiguity in Sun’s specification of the Java Card TM platform, which we noticed in the course of developing the precise formal description of the Java Card transaction mechanism presented in [HP03]. The ambiguity concerns the Java Card transaction mechanism, more in particular the interaction of the transaction mechanism and two Java Card API methods, the methods arrayCopyNonAtomic and array-FillNonAtomic in the class javacard.framework.Util. The paper also describes the experiments we performed with smartcards of two different manufacturers to find out the behaviour actually implemented on these card. Interestingly, these experiments revealed some unexpected (and unexplainable) behaviour of these two methods on some cards. Update (November 2005) Sun’s specification of the non-atomic methods has been updated, as of version 2.2, and the JCRE specification now explicitly states that “The contents of an array component which is updated using the Util.arrayCopyNon-Atomic method or the Util.arrayFillNonAtomic method while a transaction is in progress, | |||||||||||||||
Details der Publikation | |||||||||||||||
| |||||||||||||||