responding to claims about TCPA

[AARG!Anonymous]

David Wagner wrote:
> To respond to your remark about bias: No, bringing up Document Revocation
> Lists has nothing to do with bias.  It is only right to seek to understand
> the risks in advance.  I don't understand why you seem to insinuate
> that bringing up the topic of Document Revocation Lists is an indication
> of bias.  I sincerely hope that I misunderstood you.

I believe you did, because if you look at what I actually wrote, I did not
say that "bringing up the topic of DRLs is an indication of bias":

> The association of TCPA with SNRLs is a perfect example of the bias and
> sensationalism which has surrounded the critical appraisals of TCPA.
> I fully support John's call for a fair and accurate evaluation of this
> technology by security professionals.  But IMO people like Ross Anderson
> and Lucky Green have disqualified themselves by virtue of their wild and
> inaccurate public claims.  Anyone who says that TCPA has SNRLs is making
> a political statement, not a technical one.

My core claim is the last sentence.  It's one thing to say, as you
are, that TCPA could make applications implement SNRLs more securely.
I believe that is true, and if this statement is presented in the context
of "dangers of TCPA" or something similar, it would be appropriate.
But even then, for a fair analysis, it should make clear that SNRLs can
be done without TCPA, and it should go into some detail about just how
much more effective a SNRL system would be with TCPA.  (I will write more
about this in responding to Joseph Ashwood.)

And to be truly unbiased, it should also talk about good uses of TCPA.

If you look at Ross Anderson's TCPA FAQ at
http://www.cl.cam.ac.uk/~rja14/tcpa-faq.html, he writes (question 4):

: When you boot up your PC, Fritz takes charge. He checks that the boot
: ROM is as expected, executes it, measures the state of the machine;
: then checks the first part of the operating system, loads and executes
: it, checks the state of the machine; and so on. The trust boundary, of
: hardware and software considered to be known and verified, is steadily
: expanded. A table is maintained of the hardware (audio card, video card
: etc) and the software (O/S, drivers, etc); Fritz checks that the hardware
: components are on the TCPA approved list, that the software components
: have been signed, and that none of them has a serial number that has
: been revoked.

He is not saying that TCPA could make SNRLs more effective.  He says
that "Fritz checks... that none of [the software components] has a
serial number that has been revoked."  He is flatly stating that the
TPM chip checks a serial number revocation list.  That is both biased
and factually untrue.

Ross's whole FAQ is incredibly biased against TCPA.  I don't see how
anyone can fail to see that.  If it were titled "FAQ about Dangers of
TCPA" at least people would be warned that they were getting a one-sided
presentation.  But it is positively shameful for a respected security
researcher like Ross Anderson to pretend that this document is giving
an unbiased and fair description.

I would be grateful if someone who disagrees with me, who thinks that
Ross's FAQ is fair and even-handed, would speak up.  It amazes me that
people can see things so differently.

And Lucky's slide presentation, http://www.cypherpunks.to, is if anything
even worse.  I already wrote about this in detail so I won't belabor
the point.  Again, I would be very curious to hear from someone who
thinks that his presentation was unbiased.

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