[cap-talk] Security and Full Abstraction (was: Cap OS question)

[Bill Frantz]

daw at cs.berkeley.edu (David Wagner) on Saturday, September 5, 2009 wrote:

>A better goal would be to try to come up with a static analysis to
>check that the JVML bytecodes could have been produced from some valid
>Java source code.  In other words, check the full abstraction property.
>I don't really know how to do that in a simple and clean way.  (Complex
>methods scare me, because how do you know you got them right?)  The only
>approach I've been able to come up with that seems plausible it might
>work is to decompile JVML to Java source, then verify the Java source,
>then compile the source down to JVML, then execute the result.  That's
>a bit hack-ish and might have some issues.

Some of the Java obfuscators change the byte codes to build structures that
can not be de-compiled back into Java (to protect the intellectual property
of the companies which use them, of course). The idea that a Java(1) ->
byte-code(1) -> Java(2) -> byte-code(2) process would result in
byte-code(2) having the same meaning as the first byte-code(1) seems risky.

And I certainly don't want to support obfuscated byte codes in any way.

Cheers - Bill

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