TI vs. Calculator Hackers

Nyall writes "So a bunch of TI calculator programming enthusiasts got together to factor the keys Texas Instruments uses to sign the operating system binaries for the ti83+ (a z80 architecture) and the ti89/v200 (a 68k architecture) series of calculators. Now Texas Instruments is sending out DMCA notices to take them down."

Comments

Wikileaks link

[Brian Gordon]

I'm a lurker in that community and I have to say I'm extremely disappointed with TI. The community has had to reverse engineer every component of the hardware with no help from TI, and has done an amazing job writing development tools and mapping out which memory addresses do what.

Here's the wikileaks link to the keys.

Re:Wikileaks link

[Anonymous Coward]

And here's the Freenet key for the zip file: freenet:CHK@cua6vt6OGoe8dBOY2D4PR13jt~FvyvmHlMJKXPcXUgs,gFqVGC6lWjlSdE0cizGzWcyE5Y9f5J0QyWo-GNmLluY,AAIC--8/keys.zip

Re:Wikileaks link

[dgatwood]

No, this likely falls completely and totally outside that law. This project is not about brute forcing crypto keys used to prevent decrypting the firmware. AFAIK, the firmware and apps are not encrypted. This project is about brute forcing keys used to SIGN firmware. The only time a signature is covered by the DMCA is if it is used to prevent people from using illegal copies of software that for some technical reason could not be copied with such a signature (e.g. game titles installed on a hard drive). Since no TI-83+ hardware is EVER sold without a copy of their firmware, such an argument is moot. Anyone with access to the hardware also has a legally licensed copy of the firmware. Therefore, the signature does not prevent people from obtaining copies of the firmware illegally in any useful way, and as such, is not a copyright protection mechanism under the DMCA.

In short, unless TI uses DRM software resident in their firmware to protect OTHER titles from copying, this clearly falls WELL outside the realm of the DMCA. Bear in mind that there are legal precedents for what I'm saying here. Similar cases have been tried in the past (e.g. Lexmark). The courts have consistently ruled that such circumstances are not protected. Now if TI has an app store and sells applications that are coded to your particular calculator in some way, they would have a case. Otherwise, using the DMCA in this way goes way beyond silly.

DMCA Misrepresentation claim viable

[zavyman]

It's highly unlikely that the factors of an RSA private key are subject to copyright protection. Therefore the groups may have a viable claim for DMCA misrepresentation under subsection (f):

(f) MISREPRESENTATIONS- Any person who knowingly materially misrepresents under this section--
    (1) that material or activity is infringing, or
    (2) that material or activity was removed or disabled by mistake or misidentification,
shall be liable for any damages, including costs and attorneys' fees, incurred by the alleged infringer, by any copyright owner or copyright owner's authorized licensee, or by a service provider, who is injured by such misrepresentation, as the result of the service provider relying upon such misrepresentation in removing or disabling access to the material or activity claimed to be infringing, or in replacing the removed material or ceasing to disable access to it.

Texas Instruments may just have Diebolded itself.

Re:DMCA Misrepresentation claim viable

[Nursie]

Copyright?

Wouldn't this be more likely come under the circumvention of cryptographic protection techniques which the DMCA also outlaws?

Re:DMCA Misrepresentation claim viable

[zavyman]

Two sections of Title 17 (Copyrights) are relevant. 17 USC 512 (safe harbor) and 17 USC 1201 (anti-circumvention). The notice is styled as one under 17 USC 512:

It has come to our attention that the web site www.brandonw.net, contains material and/or links to material that violate the anti-circumvention provisions of the Digital Millennium Copyright Act ("DMCA"). This letter is to notify you, in accordance with the provisions of the DMCA, of these unlawful activities. Pursuant to the safe harbor provisions of the DMCA, we request that you remove any whole or partial reproductions of and/or disable links to the following:

...

I hereby confirm that I have a good faith belief that use of the Illegal Material in the manner complained of in this letter is not authorized by the copyright owner, its agent, or the law, that the information in this letter is accurate, and that, under penalty of perjury, I am authorized to act on behalf of TI, the owner of the exclusive rights in the TI-83 Plus operating system software that are allegedly misappropriated using unlawful methods.

TI appears to be claiming that the copyright in the TI-83 Plus operating system software is infringing. This therefore appears to be a notice under 512(c)(3). Anti-circumvention is a totally different section of the copyright code, 1201. There is no takedown procedure for access control circumvention materials.

But with regards to anti-circumvention claims: It appears that TI is claiming that the signing keys circumvent a "technological measure that effectively controls access to a work protected under this title." This is a term of art.

(A) to "circumvent a technological measure" means to descramble a scrambled work, to decrypt an encrypted work, or otherwise to avoid, bypass, remove, deactivate, or impair a technological measure, without the authority of the copyright owner; and

(B) a technological measure "effectively controls access to a work" if the measure, in the ordinary course of its operation, requires the application of information, or a process or a treatment, with the authority of the copyright owner, to gain access to the work.

Are signing keys necessary to gain access to the TI 83 Plus operating system binary? As far as I know, no. My understanding is that they are only used to prepare operating system images for installation onto the calculator.

Re:DMCA Misrepresentation claim viable

[Cubeman]

The keys are not required to access the binary. There is no encryption; the keys are just to verify that the OS image hasn't been corrupted. The entire binary has always been completely accessible from both the PC side (before transferring) as well as on the calculator. Furthermore, the community has had the ability to load its own operating systems on the TI-83 Plus since 2002. TI had stated in 2004 that they had no problem with independent third-party OSes being loaded, as long as (understandably) no one distributed modified TI OS files. The only new development here is that third-party operating systems can now be loaded onto the calculators without any hacks or preparation. In other words, they can be loaded in a user-friendly manner like the TI OS is loaded, and transmitted from calculator-to-calculator without having to run a special program beforehand. This is a huge deal in gaining acceptance for third-party operating systems, because end users do not want to have to pull out a battery during validation or run a strange program before loading the OS. They'd rather just click and be done.

Re:Exactly.

[plague911]

They are more successful than HP calculators. As a MS/Phd engineering student I haven't seen a HP calculator in 6 years except at a store.

Re:Streisand Effect

[spinkham]

And just in case you forget how badly that went down, here's a reminder...
http://www.youtube.com/watch?v=bSQIoXf294E

Re:Math

[elfprince13]

As a long time member of the TI community, I have to say that I'm glad Slashdot is covering this. TI consistently works against the enthusiast community, and this is blatantly obvious in their new Nspire line of calculators. The 83+/84+ line has been their one concession to sanctioned assembly programming, and they still threaten legal action against anyone who starts delving into operating system stuff.

Re:No HP???

[volpe]

Oh well, I figured everyone would get it. HP Calculators use "Reverse Polish Notation" (RPN), also known as "postfix notation". Unlike ordinary "infix notation" calculators, in which you put the operator between the two operands, HP calculators take both operands followed by the operator, thereby eliminating the need for parenthesizing an expression. So, where you might enter "5 * ( 3 + 4 ) =" on an infix calculator, you'd enter "5 [enter] 3 [enter] 4 [enter] + * " on an HP calculator. Every time you enter a number, it gets pushed on the stack. Every operator pops the top two items off the stack, performs the operation, and pushes the result on the stack.

One can write English sentences the same way if one considers the verb to be the operator, while the subject and direct object are the two operands. Thus, what I wrote was the RPN equivalent of "I can't believe that they would be so shortsighted!".