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Handhelds

TI-Nspire Hack Enables User Programming 88

An anonymous reader writes "Texas Instruments' most recent, ARM-based series of graphing calculators, the TI-Nspire line, has long resisted users' efforts to run their own software. (Unlike other TI calculator models, which can be programmed either in BASIC, C, or assembly language, the Nspire only supports an extremely limited form of BASIC.) A bug in the Nspire's OS was recently discovered, however, which can be exploited to execute arbitrary machine code. Now the first version of a tool called Ndless has been released, enabling users, for the first time, to write and run their own C and assembly programs on the device. This opens up exciting new possibilities for these devices, which are extremely powerful compared to TI's other calculator offerings, but (thanks to the built-in software's limitations) have hitherto been largely ignored by the calculator programming community."

Comment Re:DMCA Misrepresentation claim viable (Score 4, Informative) 463

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.
Censorship

Submission + - RSA keys factored, DMCA takedowns issued (sunshinepress.org) 2

An anonymous reader writes: A month ago, ticalc.org reported smart factoring of the 512-bit RSA key used by TI to sign their TI-83+ OS, which opens the door to seamless installation of open-source third-party OS on TI-83+ calculators. Since then, two other keys found in other TI calculators have been factored by a distributed effort. Several days ago, TI sent DMCA takedown notices to several sites mentioning the keys and their factors. All three keys factored so far have been posted to Wikileaks, and the effort to factor the remaining ones is going on.

Comment Re:More money... (Score 1) 123

I've found that the combination of a PC and a Wii serves my gaming needs excellently. The Wii has an excellent set of casual games (Wii Sports, Wii Fit, Mario Kart, Super Smash Bros, etc) that I can pick up and play with my gf whenever we have a few minutes to kill. The PC is great for serious gaming. A keyboard and mouse are, IMO, the best input controllers ever and the graphics on a mid-range gaming PC beat those on a 360 or PS3. I also like the fact that my games are all $50 (and not $60) new at retail.

Of course, everyone is different and I do miss out on a few 360 and PS3 exclusives, but nothing has come out for either system that has been that compelling for me.

I think when people say the Wii has "no good games", they mean it doesn't have good games like GTA, CoD, WoW, and other TLAs. But it has a ton of quick and fun, easy to learn, easy to play games that are great to play with friends, coworkers, kids, gf's, non-gamers etc.

Comment Re:Hmm (Score 1) 370

Firewalls are capable of providing all of the positive benefits of NAT (transient traffic flow approval instead of mapping for example, blocking traffic not originated from the LAN, etc) save obfuscating the source address. Obfuscating the source address isn't particularly relevant from an attack perspective given that the entire LAN is still protected by the same Firewall process, NAT or not.

For example: you could NAT your LAN in 192.168.10.x space behind IP 1.2.3.4 .. you connect to shady.com port 80 sport 192.168.10.101:2000, NAT/firewall allocates 1.2.3.4:3000 for you. Shady sees all the traffic coming from 1.2.3.4:3000, but has no way (short of client-side malware) to know that maps to 192.168.10.101; nor can Shady care since all access to 192.168.10.101 is mediated by 1.2.3.4. Shady.com might try to port scan 1.2.3.4, and see any port forwards your entire LAN uses in one swoop, try to exploit them if possible. Moral: make sure you know what you are doing when you port forward.

Or, if you use IPv6 for your LAN, let's say you are allocated 1:2:3::/112. No need to NAT it, so you just firewall behind your gateway, let's say 1:2:3::4. You connect to shady.com port 80, sport [1:2:3::101]:2000. Firewall doesn't have to allocate a damned thing for you, but instead records the flow for [1:2:3::101]:2000 shady.com:80 as established from within the LAN and thus authorized. Shady sees all the traffic coming from [1:2:3::101]:2000, but it's not relevant since all access to 1:2:3::101 is still mediated by the firewall at gateway 1:2:3::4. Shady.com can port scan 1:2:3::101 if it likes, but won't see any open ports if you only allow LAN established traffic, or else sees your whitelisted ports for that IP only (instead of your entire LAN). Just like the IPv4/NAT scenario, keep your open ports secure.

As you can see, source IP obfuscation provides no meaningful advantage to the end user in this scenario. If anything, IPv6 users who feel like they want to use NAT could have the firewall choose random source addresses as well as random source ports out of their /112, and hide their 3 LAN devices within a pool of 65 thousand addresses. Would that not confuse a would-be attacker?

Still, the major drawback to be avoided with NAT is in breaking the globally unique address space and complicating inbound connection access, which will become a growing part of popular network policy over the next few decades. One thing Bit Torrent teaches us is that "the server" will less and less frequently have resources comparable to the "client swarm", so crowdsourcing the heavy lifting (from distribution to content creation to editing to caching) becomes vital to any scaling strategy worth it's salt. The hub/spoke communication model is slowly eroding in the presence of more sophisticated, decentralized many-to-many connection models.

NAT reduces a peer to a "consumer" which can only fetch data, but never re-offer it without convoluted port forwarding messes. Entire LAN's are limited to one named service per outbound IP, unless one wishes to screw with what port they offer services on, further complicating the job for other firewalls and participants of the content network.

You'll know what I mean if you've ever tried to configure mobile SIP access. Half the time you are behind a NAT, and you'll never know in advance if it's full cone, symmetric, or just somehow pathological. Sometimes you are nested within multiple NATs which each behave differently!

Some legacy UDP protocols I've worked with need to make connections to thousands of remote IP addresses at multiple, highly transient port mappings which bring NAT mapping tables to their knees. In a firewall-only environment, it's easy to whitelist access to swaths of ports for clients and then the gateway need not maintain tables for related traffic, but can continue to protect unrelated ports unlike with SOHO DMZ.

To sum up, NAT is not only a bandaid, but it's already pulling at our short-hairs.

Comment Vote 'em Out (Score 1) 198

Members of parliament need to be reminded that they work for us, not Big Media Corp. They need to be reminded that their job security depends heavily on our support, not the support of a corporate lobby group - especially a FOREIGN lobby group. Members of parliament need to become aware that serving the interests of the people whom they represent is their number one priority and serving the interests of lobby groups can come somewhere much further down on that list. They need to be reminded in the simplest and best way possible - they need to be informed that, if they fail to represent the best interests of the people, the people will replace them with someone who understands their role better. They need to be reminded that Big Media Corp might be represented by a large and powerful lobby group but "the population at large" is a much large, much more powerful lobby group and we, as the population at large", are willing to flex our muscles if we aren't being represented properly.

Write to your member of parliament. Vote smart.
Handhelds

Submission + - TI-83 Plus 512-bit RSA Key Cracked

Cubeman writes: "The 512-bit RSA key protecting the operating system of TI-83 Plus and TI-84 Plus calculators has been cracked! Benjamin Moody posted the factorization yesterday, and it has been verified by Brandon Wilson. With the RSA key broken, developers can now release cryptographically signed third-party OSes which will validate on any unmodified calculator. While TI's security protections have previously been broken, all prior hacks required loading an extra program on each calculator. This broken OS key means that the last frontier of TI hacking has finally been achieved. Calculator programmers now have complete control over every area of the calculator and can write any code in any form, even entire operating systems, and distribute them freely on any 83+/84+ calculator in existence. ticalc.org has an article about this as well."
Handhelds

Submission + - TI-83 Plus 512-bit RSA Key Cracked

Cubeman writes: "The 512-bit RSA key protecting the operating system of TI-83 Plus and TI-84 Plus calculators has been cracked! Benjamin Moody posted the factorization yesterday, and it has been verified by Brandon Wilson. With the RSA key broken, developers can now release cryptographically signed third-party OSes which will validate on any unmodified calculator. While TI's security protections have previously been broken, all prior hacks required loading an extra program on each calculator. This broken OS key means that the last frontier of TI hacking has finally been achieved. Calculator programmers now have complete control over every area of the calculator and can write any code in any form, even entire operating systems, and distribute them freely on any 83+/84+ calculator in existence. ticalc.org has an article about this as well."

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