[Cryptography] Apple GovtOS/FBiOS & Proof of Work

[Tom Mitchell]

On Sat, Mar 19, 2016 at 7:04 AM, Henry Baker <hbaker1 at pipeline.com> wrote:

> At 03:45 PM 3/18/2016, Michael Kjörling wrote:
> >And of course, the presence of any "fiddlable" sections implies that
> there is data in the firmware that doesn't really do anything at all.
> >
> >You can't go around flipping bits in highly specific machine code or even
> data used by it and expect nothing to happen; it has to be a portion that
> just sits around unused

.....

> BTW, the hash *includes* the hash of the previous firmware, so neither
> Apple -- nor anyone else -- can develop multiple firmwares in *parallel*.
>

Some layers of crypto, checksums and integrity may have been overlooked in
this Applesauce, iTunes.

In the case of Apple I suspect there are two perhaps three checksums to
give attention to.
There is the hardware set of keys in the phone that allow the hardware to
load the bits and decrypt
the data in question.   This is the last step and if buggered the data is
lost.   Then there are
OS integrity bit checks to verify the system and trigger a reload ASAP from
the mother ship.
These may make fiddling idle bits an unworkable strategy for additional
hacks.
The overlooked third set involves the external tool to load the bits that
may involve multiple checks and signatures.
In this case iTunes would be the tool to load the new software, I assume an
OTA download is
out of the question ;-)   iTunes downloads and checks the image in ways
that iTunes knows and
ways that are not documented in the public phone security model
documentation.

Google quickly found foo.com
"In its earnings report, Apple showed that its "Services" division -- made
up of the iTunes Store, App Store, and Apple Pay -- increased revenue
by 9% year over year to $5 billion".

So one component of the ask is to compromise or modify a version of iTunes
to allow a
side loaded binary file to be accepted, identified as newer than and pass
download
related  unpack checks and signatures.

iTunes can modify software on all Apple portable devices (iPhones, iPads,
iPod,
all except the MACs).

Given that iTunes is a 5 billion dollar revenue stream, it is also an equal
or larger cash
flow issue to the movie and music industry.

If this is not the definition of unreasonable I am curious where the line
to unreasonable
lives.

>From my bleacher seat, this seems punitive in an extra legal way.

One observation is the bigger boys like Apple have seen departmental
budgets grow as law enforcement and FISA warrants are serviced.  Secrets
like these make it difficult or impossible for executive and necessary
corporate
oversight. I suspect the internals of global law enforcement related
services are largely
invisible to auditors and fiscal oversight.   Trust me the bill is
<$XXXXXXXXXXXXXX.00>

So simply fiddling some bits in an object to satisfy a check sum check
seems insufficient.

Interesting...






-- 
  T o m    M i t c h e l l
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