
Battle of the Clipper Chip (1994) - Cieplak
http://www.nytimes.com/1994/06/12/magazine/battle-of-the-clipper-chip.html?pagewanted=all
======
oceanghost
This article only hints at what was well known at the time-- that this was
simply the first step in an attempt to outlaw cryptography altogether.

The next step was to either pass a law requiring key disclosure, our outlaw
cryptography alltoegether. If you think that sounds far fetched... remember at
the time this article was written they were trying to jail Phill Zimmerman for
writing PGP.

~~~
delinka
"...they were trying to jail Phill Zimmerman for writing PGP."

 _Writing_ it or exporting it? Sure, their motivations may have been due to
the former (is there even documentation for that?), but IIRC the technical
reason was that, because it'd been made available online for anyone on the
planet to download, they tried to pin "export of munitions" on Phil.

~~~
oceanghost
What method would you propose could be used to allow only US citizens to use a
piece of software?

The law is pretty damn clear. Create strong encryption, go to jail.

~~~
delinka
It's not the author's job to prevent use of his software by specific
individuals as deemed by the US government. It is, however, any citizen's
responsibility not to break the law by sending or carrying stuff outside the
US.

And indeed, the law is pretty clear: export "munitions" (according to a list -
at the time "strong encryption" was on the list) and you'll feel the wrath of
Uncle Sam. But they dropped their case against Zimmerman. Never filed charges.
Probably because there was no evidence that he was the one to export PGP.

~~~
reaperducer
>It's not the author's job to prevent use of his software by specific
individuals as deemed by the US government.

I think the gub'mint might have a different opinion on that.

I used to have a GRiD Compass laptop computer that came to me via a friend of
a friend of someone in the Reagan administration. On the back of it was a list
of countries in which it was legal to operate or possess the computer, due to
the software inside.

~~~
delinka
So the author wasn’t preventing a thing, but relying on the operator of the
system to observe the list and behave correctly.

------
pjc50
Operation of Clipper: [http://www.crypto.com/papers/escrow-
acsac11.pdf](http://www.crypto.com/papers/escrow-acsac11.pdf)

"Clipper was intended as a drop- in replacement for a standard DES chip, but
with a new symmetric-key cipher algorithm, called Skipjack , designed by the
National Security Agency and using an 80 bit key. But before any two Clipper
chips could communicate, they would first exchange a Law Enforcement Access
Field (LEAF) that contained a copy of the current session key, itself en-
crypted with an “escrowed” Unit Key held by the govern- ment. Any Clipper-
encrypted communication could thus be decrypted by government agents without
needing to break the (presumably strong) Skipjack cipher. The agents would be
able to recover the session key simply by decrypting the copy in the LEAF
(which they would intercept along with the ciphertext) using their escrowed
copy of the unit key"

It had a fatal flaw: a 16-bit checksum that could be brute-forced.

------
Cieplak
Thought it was interesting that plans for the Clipper Chip were canceled
around the time the recently discovered CPU vulnerabilities were introduced.
Extremely unlikely that there was some conspiracy given the number of vendors
affected, but a possibility given the magnitude of the military budget and the
value of being able to decrypt enemy communications via side-channel attacks.

~~~
Fnoord
Does SELinux mitigate Meltdown and/or Spectre?

~~~
pjc50
No, it's just a (hard to use) capability system.

------
corysama
The documentary “The Century of the Self” has a section on the Clipper chip.
It showed video of a Clinton campaign manager explaining to volunteers that
“Yeah, we know this is stupid, but it’s an important part of our message that
we are here to protect your children.”

The documentary is excellent all around. Highly recommended. Possibly
available on YouTube.

~~~
Fnoord
That's a documentary by Adam Curtis [0]. Various of his documentaries are
generally available on Archive.org, including this one. Its 4 parts [1] [2]
[3] [4]. I've seen The Power Of Nightmares and The Century Of The Self. Both
highly recommended though I didn't remember Clipper chip was mentioned.

[0]
[https://en.wikipedia.org/wiki/Adam_Curtis](https://en.wikipedia.org/wiki/Adam_Curtis)

[1]
[https://archive.org/details/TheCenturyOfTheSelfPart1](https://archive.org/details/TheCenturyOfTheSelfPart1)

[2]
[https://archive.org/details/TheCenturyOfTheSelfPart2](https://archive.org/details/TheCenturyOfTheSelfPart2)

[3]
[https://archive.org/details/TheCenturyOfTheSelfPart3](https://archive.org/details/TheCenturyOfTheSelfPart3)

[4]
[https://archive.org/details/TheCenturyOfTheSelfPart4](https://archive.org/details/TheCenturyOfTheSelfPart4)

------
pmoriarty
How does the Clipper Chip compare to more modern technologies like the Intel
Management Engine?

~~~
excitom
"Cryptography is the silver bullet by which we can hope to reclaim our
privacy. The solution, however, has one drawback: cryptography shields the law
abiding and the lawless equally. Law-enforcement and intelligence agencies
contend that if strong codes are widely available, their efforts to protect
the public would be paralyzed. So they have come up with a compromise, a way
to neutralize such encryption. That's the Clipper chip and that compromise is
what the war is about."

So there it is, a government-mandated encryption device that has a backdoor
built in.

The IME is a well-intended system management feature that can be turned to
nefarious purposes since it can go around all operating system security
features, e.g. read or update all of the system's memory.

~~~
Nullabillity
If the IME was well-intentioned then it would have been easy to disable, and
the source code would have been public.

~~~
pjc50
Firmware is never public, it's just proprietary code. Closedness tells us
almost nothing about intent.

