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Comment IPMI and other "lights-out" (Score 2) 564

Don't underestimate IPMI and its equivalent (what was Intel's name for their proprietary alternative? ME ?)

With this kind of technologies, you have a small mini-embed system in the motherboard, which talk over a TCP/IP network and provides all functionnality (including wake-on-lan, including shutdown, including reboots (AND specifying what resource to reboot to - like starting PXE or emulated-over-network USB driver), including VNC remoting, and Serial-over-IP (for some server remoting).
Think of all the niceties you have inside a VirtualBOX or VMWare emulator, but on actual real hardware.

It's very popular in enterprise settings so sysadmins can update a whole division's computers, instead to having to walk to each one of hundreds of machine).
So it available under some form on most workstations, servers, and enterprise laptops.

If you need to upgrade machines, the usual procedure is:
1. you politely ask the user to not start any over-night computation and if possible leave their machine off.
2. when the evening comes you log into the lights-out management of each of the target the workstation over *IP* (no MAC-address shenningans, straith IP address) (you either have simple accounts with password, or you can have it integrated to some larger systems)
3. because none of the user would have actually left the workstation off as requested, you first try to nicely shutdown the machines (you send an ACPI soft-off signal, and hope that the OS will react and nicely save and shutdown).
4. after a timeout you force shutdown the remaining machines (you send a Reset or Power OFF signal)
5. you boot all the machine and ask them to load your payload instead of the disk (it can be either classical PXE, or you can remotely emulate a USB drive) so all machine boot the management software even that bizare guy who insist on having CD as his primary boot device on his workstation.
6. you remotely launch the necessary administration. Either it runs unattended, or you can remotely control if needed (depending on the tool used, you might use a proprietary administration tool, or SSH, or Serial-over-Internet. If it's an asinine tool, you might need to VNC)
7. you reboot the machine and let them follow normal boot order.

The system has lots of advantage:
- it can be scripted with command line tools.
- you can even change BIOS settings, etc.
- it's handled by an embed system (usually part of the chipset) so this is completely independent of what the main CPU is doing (the workstation might be running or might be powered off).

The system has a few drawbacks:
- massive security problems: the user-friendly web-interface of lots of "lights-out" implementation is buggy and an exploit-nightmare (most securing recommandation start by "turn the web console off").
- security problem: you need to setup proper accounts and passwords (to avoid a script kiddie wrecking havock after having guessed a few standard passwords. Minimum is setting acceptable local accounts)

So, going back to the discussion:
- if the workstations have Lights-out remote administration (virtually all enterprise hardware is sold with)
- if the remote administration is properly setup...

You have full control possibilities on the whole fleet of workstations, without any of the hassle of dealing with low-level functionnalities like PXE, WOL, etc.

If an administrator has done a bad job at automating it all, you might end up with the whole enterprise being remotely reformated.

At least the students machine are probaly safe:
- the consumer grade laptops don't usually feature "lights-out" management.
- the student who has bought an enterprise-class laptop probably hasn't it activated (and if the student is savvy enough to turn it on for own use, the student has sure enough setup decent accounts).

Given the security problems mentionned above, that means NSA and China have probably full administrative access to 1/3 of all enterprise workstations running everywhere.

Comment Battery swap (Score 1) 160

But a trainer should be paying for itself and this will spend too much time on the charger for that.
But the flight school won't be impressed with 45 min flight and an hour (is that all?) on the ground to recharge.

Non experimental-versions of this aircraft (such as potential trainer that you mention), could implement swappable batteries.
(As it's the case with Tesla Model S. The battery is designed to be swappable and Tesla is working around a "fresh battery rental" system).
In that case, the thing which is spending time on the charger is the spare battery pack, while the other pack is flying in the air craft.
Have 2 (or 3) sets of battery rotating, and you don't need to think about charging times.
The time schedule now looks much more like fuel (except you swap in a fresh battery, instead of pumping fuel).

Comment Why Google? (Score 5, Insightful) 370

I still fail to follow the court's logic.

Google isn't *publishing* information, it's just indexing information (web page) already available elsewhere (on 3rd-party webservers).

If the businessman doesn't like being associated with his previous bankruptcy, he should ask the *website of the newspaper* to remove the article about the bankruptcy. Not ask google to stop indexing it.

Because:
- If he stops Google. Bing and any other search engine would still be indexing it. And the original article is still outthere. It's a completely ineffective measure.
- If he stops the newspaper, the information will indeed be definitely disappearing. On the next crawl, Google's, Bing's and anyone else's spider will notice the page doesn't exist anymore and will stop displaying it in search result. The article would only be accessible in things like archive.org

It seems like the judge in that case don't understand that much the functioning of search engines and the implication of the ruling.

On the other hand, I understand why the businessman went after google:
- trying to remove an article basically amounts to censorship. That's a big taboo (not as much here in EU as in US, but still the case as there are no hate-speech in this suit) and the businessman was probably going to lose
- trying to attack google, looks like going after the big giant with pervasive snooping and privacy-problems. Much likely to win.

Comment Make-Up (Score 1) 196

I don't know about your jurisdiction, but the several european I know of, only forbid *Masking* the face (i.e.: hiding the face behing an object. what is forbiden is covering the face).
Make-up is still allowed (as long as the face is not covered by an object you can put as much colours you want on it), and face recognition has already been shown to be prevented by some types of make up.

Comment Monopoly (Score 5, Insightful) 85

monopoly? huh... how?
They are dozens of 3D printers models out-there, both by big brand (like Materialize) or very small maker groups (RepRap), based on several different technologies (glued powder, extruted melted material, laser polymerisation, etc.).

There's a clear open standard to transfer data (STL).
This format is documented (and is brain dead simple).
Anything that can spit this format can be used for 3D printing.
Any printer that can eat this format will print.

The only ploy for Autodesk is that they are a dominant actor in the market of software used to make the models (the "STL spitting" mentionned above).
The more the 3D Printing market expands, the more demand for models, and thus the more creator may buy Autodesk professionnal ).

But no monopoly is going to take over the STL ecosystem,
just like the post-script ecosystem didn't got taken over by HP.

Comment GnuTLS, NSS, etc. (Score 1) 113

Yup. Heartbleed only affected software running openSSL.
Apache *is* running on openssl, so given that's popularity, heartbleed did affect a lot of websites.
Also curl and wget use it, so a lot of client-side scripts and cron jobs could have been attacked by a rogue webserver.

BUT
it didn't affect GnuTLS (though that one has has its share of problems, too).
and it's very widely used too.
So purple (= pidgin, adium and many other multichat systems), exim (= a huge chunk of email servers), cups (= anything that prints and isn't windows), etc. weren't affected.

it didn't affect Mozilla's NSS
and that one is very popular too (specially in web browser).
So almost Firefox wasn't affected, Chrome wasn't affected, OpenOffice[*] wasn't affected, Purpe use that in addition to GnuTLS but wasn't affected either.

*: Normally used mostly for WebDAVS. But could also use it to retreive any information online (downloading files from HTTPS), including by extentions (think Google Drive syncrhonisation or simply small weather bug).

And that's just 3 big name in the SSL/TLS world.
Not exactly a monoculture, even if openSSL is a bit to much popular.

Comment Does not exist (Score 3, Interesting) 88

Using software that explicitly makes it impossible for you to comply with the law is not defense against the law.

It's not that the software doesn't comply with the law. It's just that the things that your are asked to provide in the first place simply DOESN'T EXIST (provably, per math and crypto science).

Like said by gnasher719 somewhere else among the comments on this /. entry :

It's like two shops, one with a video camera running and one without. The shop with the video camera must hand recordings over to the police if there was a crime in front of the camera. The shop without the video camera doesn't need to do anything, and doesn't have to install a camera just in case someone gets stabbed in front of the shop.

The second doesn't have any record to disclose if ordered by the court. There just don't exist any recording that they could hand over. There security relies on some completely different scheme (say, a heavily armed bouncer/guard) which doesn't involve any camera nor any recording that could be handed over.

OTR relies on a completely different form of encryption (perfect forward secrecy, powered by ephemeral diffie-hellman) that doesn't involve permanently stored passwords. So there's nothing that you could hand over, even if asked by court.

It can potentially be defense against revealing your secrets in the face of "rubber-hose" decryption attempts, but unless your secrets are *really* important you're unlikely to appreciate being unable to reveal them under duress.

The goons who are going to beat you, to obtain a password, even if no password exists, are probably going the same goons who are beating you into revealing a password to get access to your huge stash of monney, even if you're actually broke. You know, just beat you in case there's a slight chance to get some money. Don't listen that you don't have a password, or that you don't have money. Maybe they should beat you a bit more. You know, in case you're bluffin and you actually have a password, or actually have money (hidden by another password that you haven't caugh up yet). Or maybe you gave them money, and they'll beat a bit more just to see if you don't have more of it. Who knows what they are going to get if they keep beating you? More money? Or plain more fun while beating you ?
There's no point of anything. Brutal goons who have decided to beat are going to beat your poor soul out, no matter what. Either you have a password or not. Either you already gave a couple of passwords or not. Either you have money or not. Either you already gave some money or not. They'll make you miserable even a bit more just in case.

Cryptography is only a defence against lawful individual. Who follow law and have to follow due process. They can't require you to provide something that provably doesn't exist. And modern day cryptography helps you bring irrefutable proof that the password doesn't exist.
(gnasher719's camera doesn't exist, so you provably don't have any records to bring to court).

Comment Camera vs. Password (Score 1) 88

It's like two shops, one with a video camera running and one without. The shop with the video camera must hand recordings over to the police if there was a crime in front of the camera. The shop without the video camera doesn't need to do anything, and doesn't have to install a camera just in case someone gets stabbed in front of the shop.

Yup, nice image. The second doesn't have any record to disclose if ordered by the court. There just don't exist any recording that they could hand over. There security relies on some completely different scheme (say, a heavily armed bouncer/guard) which doesn't involve any camera nor any recording.

OTR relies on a completely different form of encryption (perfect forward secrecy, powered by ephemeral diffie-hellman) that doesn't involve permanently stored passwords.

Comment Reuse as much as possible (Score 1) 88

Two words: network effect. {...} I installed an XMPP daemon on a home server and made it as easy as I could to get everyone going.

Baby steps. Having them use an existing facility like XMPP interface to GoogleTalk/Google+Hangouts, or the XMPP interface into Facebook would have been a smaller jump, or the SIP provider to their home telephony (if they use a combined "Internet + IPTV + VoIP" package).
(Though some would have complained that facebook sticker don't work currently over XMPP)

Then start handling separately the cryptographic issue.
(Once everyone is used to have Adium on their Mac to chat with Google Talk and Facebook contacts, its easier to "just turn on" crypto).

"If this is so secure, what's this certificate warning about?"

Oh, common. Do some effort on your side. It's not that difficult to use a free CA like CACert.org.
It's even a recognized certificate in some browsers.

"Why do I have to do this?"
"What's wrong with Skype?"
"Oh, you're so paranoid!"

Big thanks to Snowden for making this a tiny bit more obvious to the avrage sheeple.

Until it "just works", nothing is going to change.

In their defense, Jitsi (the only client with OTR and ZRTP, as far as I know) is pretty buggy.

Yup, we need more efforts to have a wider choice of crypto-enabled clients.
Adium and Pidgin are nice alternative (but only support OTR, and only support Skype through some extra 3rd party plugin).
Tor is working into adding Instant Bird (XUL powered) with OTR to their bundle.

Comment Crypto vs. all. (Score 1) 88

I quite agree, the technology changed, and we need to both change with it, and take advantage of it to create stronger guarantees.

And my point of view is that by using decent, suddenly we don't rely on anything else.

I actually think we need a defence in depth. Guarantees offered by an arms-length postal service, technical means of testing the protections, legal protection from the law where the guarantees are breached, and enforcement of the law by independent, arms-lengths police under the oversight of a string court system. Add to that a technology that makes it impractical for a middleman to leak one's information, and protection against a security service demanding your keys without laying a 20-page "information to obtain" before a non-trusting judge.

And all this is unneeded in case of good crypto.
All this would require long pollitical adventure until its finally accepted in law and enacted.
Meanwhile crypto works as of tofay in the current environment.

To take again a metaphor: imagine that you want to protect your car against act of vandalism from the government.
You could either push for the acceptance for a legislation forbiden the government to behave as vandals, and that exception to this need thorough justification filed with a judge (asking for guarnatee in law).
Or you could just lock your car into your garage (just use crypto). That's something you can already do today, and that's already efficient even if there's a law that makes it mandatory for the government to trash any car that they happen to encounter on the public road (= the current state of mass surveillance).

We're not just protecting ourselves against the watchmen: we're also protecting against plain ordinary villains, ones who will snatch your letter out of your hand and go belting off down the street with the "Bow Street Runners" in hot pursuit!

That's why I'm not so much in favor of legal guarantee.
Although government could be forced to comply by law (i.e.: guarantee not to do mass surveillance), criminal won't abide the law and they would still try to violate your privacy even if it's illegal.
Meanwhile, by using technical means, not only government is prevented (even if current law would have allowed them to. it's just not technically possible for them) but criminals to (no matter if do or don't follow law forbiding them. It's just plain not technically possible).

At the same time, we don't want to depend on a single point of failure.

...well, we could add an extra legal layer, as long as the technical (cryptographic) layer is here.

our email system is at least as horrible as post-cards, and perhaps even worse

At least post-cards aren't as trivial to duplicate as digital data like e-mails. And at least handwritting gives some minor form of identification and tamper-proofing.
(And the writing of some MDs like me should straigh go into the "undecipherable crypto" category :-D )

Comment Provable (Score 1) 88

that will only give the court a reason to add a "destruction of evidence" charge on top of "refusing to reveal keys".

It is clearly provable that the required key DO NOT EXIST in PFS (like DHE or ECDHE).

What you mention would be recieving a court order requiring you to bring a *pink unicorn* in court, and get subsequently jailed for "destruction of evidence" when you claim that no pink unicorn exist.
Just like no pink unicorn doesn't exist, it's simply provable by math and crypto science that no key exist that you could reveal (that the whole point of this class of algorithms).

It's not that the law is unjust, it's that it can be scientifically proved that the law is impossible to follow.
Jailing for "destuction of evidence" make exactly as much sense as jailing for "failing to bring the required pink unicorn".
NO PINK UNICORN EXIST, NEITHER DO EXIST ANY PERMANENT DISCLOSABLE KEY IN P.F.S (as proved by math and crypto science)

Any defense attorney worth its salary should be able to defend this in court.

But, as I've said above and as the previous poster said:

it works right up to the moment when it is a crime if you use non-government approved encryption methods.

The Australian government could make a future law making mandatory to use special forms of crypto, that DO use keys (say bye-bye to DHE/ECDHE or at least ECDHE with a secure elliptic curve) and that require the key to be deposited in a government-accessible escrow (like requiring the password to be transmitted crypted with a government-own public key, or requiring ECDHE with government-compromised curve).

The australian government just needs to make perfect forward secrecy illegal.
And then, they can jail you on the ground that you've been using a crypto that doesn't involve key and that can't be court-ordered into revealing. End of problem for them. Start of immigration to a better country for you.

Comment Google+ Hangouts and OTR (Score 1) 88

Extra note:

One of the things that don't work with Facebook and the new Google Hangout's, namely lack of history, doesn't make that much sens with OTR anyway.
OTR use ephermeral encryption. There's no permanent key.
If you access old encrypted history (what would be contained in GMail and visible in the full blown Hangout+ app, for example) there's no way to decypher it, the information doesn't exist anymore.
(That's the whole point of Diffie-Hellman used in OTR and the whole Perfect Forward Secrecy: there doesn't exist any piece of information that make it possible to decipher past stored encrypted information).

So you aren't losing much from that point of view.
Now the other things (lack of sever-2-server protocol support, meaning that Google+ Hangouts and Facebook chat are basically isolated islands) is still a sad problem.

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As far as the laws of mathematics refer to reality, they are not certain, and as far as they are certain, they do not refer to reality. -- Albert Einstein

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