Palladium and malware

[Bill Frantz]

At 9:00 PM -0700 8/30/02, Nomen Nescio wrote:
>Bill Frantz writes, regarding the possibility that the Palladium
>architecture could be designed to resist the use of encrypted
>code:
>
>> All general purpose computers require a way to move data space to code
>> space to support compilation.
>
>Well, this is usually done by storing the data to the disk, and
>then later loading it as a program file.  It does not prevent data
>and code memory from being distinct, which was the proposal for how
>Palladium could reduce the risk of being used to run encrypted code.
>If a Palladium program was forced to go through the disk, that is, to
>load data, decrypt it, store it to the disk, and then load it as code,
>then that would provide a means to get access to the unencrypted code,
>defeating the goal of keeping the code within the "vault".

Usually, but not always.  Just-in-time compilation systems take interpreted
code sequences and compile it, in RAM, to machine instructions.  A number
of Java virtual machines make use of this technique.  More relevant, it is
also applicable to some of the Microsoft languages.


>> Even if you don't allow compilation, most
>> modern systems have enough different powerful scripting languages that
>> interpretation is sufficient to support viruses.
>
>It's not clear why these languages would use the Palladium features and
>run their scripts in the shielded mode.  But you're right that if they
>did, this could provide a mechanism for disassembly-resistant code.

Well, some vendors might want to protect their scripts.  Just because a
program is written in an interpreted language instead of a compiled
language doesn't mean that vendors don't want to protect their code.  There
is an active market in Java obfuscators for just this reason.

Cheers - Bill


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