It's a pretty cool hack to reuse crypto primitives in order to implement some operations.<p>If you're not very familiar with JavaCard and why this would be noteworthy, JavaCard is basically a very stripped-down version of Java that only bears some similarity to regular Java SE. Amongst these limitations is a very stripped down standard library (there is no java.lang.String for example), only a few types (byte, short and arrays of bytes, support for int is optional, no support for char, long, double, float, etc.) and no garbage collection (so everything is preallocated at program start, including exceptions).<p>Given these limitations, implementing newer crypto algorithms is quite a feat.
I don't know very much about this field - what are the major uses of JavaCard other than in SIM cards?<p>Or are SIM cards where this OpenCrypto would be most useful for makers/researchers?