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Submission + - Linux Random Number Generator Sees Major Improvements (zx2c4.com)

An anonymous reader writes: The Linux kernel's random number generator has seen its first set of major improvements in over a decade, improving everything from the cryptography to the interface used. Not only does it finally retire SHA-1 (in favor of BLAKE2s), but it also at long last unites `/dev/random` and `/dev/urandom`, finally ending years of Slashdot banter and debate:

The most significant outward-facing change is that /dev/random and /dev/urandom are now exactly the same thing, with no differences between them at all, thanks to their unification in random: block in /dev/urandom. This removes a significant age-old crypto footgun, already accomplished by other operating systems eons ago. [...] The upshot is that every Internet message board disagreement on /dev/random versus /dev/urandom has now been resolved by making everybody simultaneously right! Now, for the first time, these are both the right choice to make, in addition to getrandom(0); they all return the same bytes with the same semantics. There are only right choices.


Comment Well, that's embarrassing... (Score 5, Informative) 54

Hi folks, I'm Jason, the guy who found this bug.

I feel kind of embarrassed this is on the front page. I like to think that I spend time doing cooler things than reading PHP, let alone the source of random Wordpress plugins. My brother lives at the south pole and has a pretty damn cool blog about it (yay, more linkspam!), but the NASA satellite only flies overhead a few times a day, and bandwidth is pretty limited, so he asked me to help with some maintenance, and in the process I noticed this. But now the Intertubes have me pinned as a Wordpresser, alas. I guess that's just how it goes.

Anyway, my feeling on this is basically, to put it in /. terms -- "Random Wordpress plugin has gaping security hole... news at 11!" If you want a reasonably secure Wordpress rig, it's probably best to stick with plugins and themes put out by Automattic.

It wasn't mentioned in the linked article, so it's worth nothing here -- I think the best remediation, until W3 Edge releases a fix (he's on Christmas vacation now or something I think), is to either disable the plugin entirely, or, if that's not a possibility, just disable the object cache and database cache, and then empty all caches. Doing that should at least clear up this hole.

-- Jason

Comment Q: What in 1 shouldn't lead to 2? (Score 1) 88

1: "The suspect in the spy data theft worked for the NDB, or Federal Intelligence Service, which is part of Switzerland's Defense Ministry, for about eight years."
2: "He was described by a source close to the investigation as a "very talented" technician and senior enough to have "administrator rights," giving him unrestricted access to most or all of the NDB's networks, including those holding vast caches of secret data."

A: "for about eight years" --> "unrestricted access to most or all of [...] vast caches of secret data"

Eight years? That's it? Really?

Comment Some Simple Wiresharking... (Score 5, Informative) 359

It appears to just be PPTP, with the credentials generated dynamically from a JSON HTTP endpoint. There's a required ping URL the client has to hit every 900 seconds in order for the credentials to stay alive. Shouldn't be too hard to make an open source client.

Interestingly, the JSON config endpoint contains a list of IP address ranges that should be excluded. Haven't started investigating these yet, but here are the ranges if anyone wants to look:

  • 8.34.208.0/20
  • 8.35.192.0/20
  • 64.15.112.0/20
  • 64.233.160.0/19
  • 66.102.0.0/20
  • 66.249.64.0/19
  • 70.32.128.0/19
  • 72.14.192.0/18
  • 74.125.0.0/16
  • 89.207.224.0/21
  • 108.59.80.0/20
  • 108.170.192.0/18
  • 108.177.0.0/17
  • 142.250.0.0/15
  • 172.217.0.0/16
  • 173.194.0.0/16
  • 173.255.112.0/20
  • 193.142.125.0/24
  • 199.192.112.0/22
  • 207.223.160.0/20
  • 208.65.152.0/22
  • 208.117.224.0/19
  • 209.85.128.0/17
  • 216.58.192.0/19
  • 216.239.32.0/19
  • 67.63.48.0/20
  • 77.247.182.224/28
  • 216.185.96.0/19
  • 65.60.0.0/18
  • 69.175.0.0/17
  • 198.143.128.0/18
  • 173.236.48.0/24
  • 184.154.151.0/24

Comment Don't turn students into drones. (Score 0) 120

At the recommendation of another comment, I just watched the demo video for jupitersis. I was horrified. One unified solution for students, teachers, and parents to check grades, assignments, discipline, schedules, and more.

My objection is that there is something to be learned from the good old fashioned way. Students need to learn to write down or remember their assignments and keep track of how they're doing in class by themselves. Maybe that means a motivated student will build his own gradebook. Maybe that means other students will learn to manage a planner. And maybe other less dull students will develop a memory inside their brains. Whatever the means is, this classic exercise of remembering grades and assignments is a cornerstone of childhood education.

And then there's the discipline issue. A screenshot in that demo video showed a nice citation webpage with checkboxes like "[x] gum/food [x] violence [x] talking". This bureaucratic approach only serves to depersonalize discipline and prematurely convert youthful chaps into the office drones that many will become. When students act up, parents and teachers should be aware of it on a personal level, and monitor for any deeper issues that can be dealt with sensitively.

The discipline chart also had boxes for "[x] email parents [x] notify parents on login [ ] notify dean". The automation of informing parents is frighting. There's something to be said about the not knowing if the parents know, when a student gets in trouble at school. There is a healthy guilt associated with it, that can translate into a productive dinner table conversation. It also educates the student's human sensibilities -- he learns to gauge who is likely to inform whom, and at what time, and become sensitive to all the small human factors that make the world go round.

If anything, "solutions" like jupitersis only serve to raise children for a 21st century bureaucratic totalitarian society, which even if this is the state of the world, children should at least have their childhood.

As for the question in TFA, which I believe was about how teachers should manage their grades, each teacher should manage it by themselves. No need to subject teachers to any more needling paperwork. Some teachers like old fashion grade books with the nice rows and columns. Other teachers are Excel aficionados. Let the teacher do what's most organic to his or her teaching style.

Moral of the story: technology is not the solution to childhood education.

Comment Server Execution is the Issue (Score 5, Informative) 70

Most quality web hosting provides customers with shell access to the web server, or when cases where they don't, usually something like PHP is installed that usually allows for arbitrary execution.

On a web server that hosts a few thousand sites, using the Bing IP Search, you can find a list of all the domains. Usually there will be a lowest hanging fruit that's easy enough to pluck. Or, if you can't get shell access through a front-facing attack, you can always just sign up for an account with the hosting company yourself.

So once you have shell, then it's a matter of being a few steps ahead of the web host's kernel patching cycle. Most shared web hosting services don't utilize expensive services like ksplice and don't want to reboot their systems too often due to downtime concerns. So usually it's possible to pwn the kernel and get root with some script-kiddie-friendly exploit off exploit-db. And if not, no doubt some hacker collectives have repositories of unpatched 0-day properly weaponized exploits for most kernels. And even if they do keep their kernel up to date and strip out unused modules and the like, maybe they've failed to keep some [custom] userland suid executables up to date. Or perhaps their suid executables are fine, but their dynamic linker suffers from a flaw like the one Tavis found in 2010. And the list goes on and on -- "local privilege escalation" is a fun and well-known art that hackers have been at for years.

So the rest of the story should be pretty obvious... you get root and defeat selinux or whatever protections they probably don't even have running, and then you have access to their nfs shares of mounted websites, and you run some idiotic defacing script while brute-forcing their /etc/shadow yada yada yada.

The moral of the story is -- if you let strangers execute code on your box, be it via a proper shell or just via php's system() or passthru() or whatever, sooner or later if you're not at the very tip top of your game, you're going to get pwn'd.

Comment Before anyone gets ahead of themselves... (Score 5, Informative) 283

I'm a good friend of John, the blog post author, and have been working with him throughout this process in trying to unravel Hamstersoft's deceit. I want to make a few things pretty clear:

Yes, they posted a zip of code on a hard-to-find link. But they did something sneaky. They included the very short and trivial C# wrapper around Calibre, but they only included a compiled (well, .NET dll) binary blob of the bulk of the application code -- the user interface. And of course, since all the heavy lifting is in Calibre itself, this code is the most important part of the application. They went through pains to extract the source of the UI components and only include it publicly as already compiled. They even packaged it up in a nice Visual Studio Solution so that you can load it up and hit "compile" and you get the software. It looks, at first, like they've complied. But then you dig into the source code actually provided, and it becomes obvious that they haven't provided the majority of the code at all, but only the wrapper code and a few call outs to the provided compiled DLL.

Cheap trick.

The other thing to take notice of in John's post is that in fact the search engines and Facebook have hardly complied -- there are still search results and Facebook pages for this company. Now, you can debate and troll and bikeshed and argue the validity and ethics of the DMCA all you want, but the fact of the matter is that when the big companies want to use it against the small, it seems to work, but when some OSS devs want to take the case up with giant companies, the response is exceedingly lackluster. (Likely, this being on /. will change things, we'd hope...)

The final point to consider is what this all means for GPL and OSS. Hamstersoft is Russian, so good luck trying law suit or anything. But at the very least, shouldn't the OSS community have an army of lawyers willing to work probono, or financed by various foundations, for this kind of thing exactly? John mentioned he tried contacting one such organization, and was unsuccessful. He's told me that at another point, he got in contact with a lawyer from another place who didn't offer to do any work for him but vaguely suggested he send these notices to Google, Facebook, etc. That's pretty lackluster. I don't want to complain to loudly, but instead I just want to suggest that this issue call our attention to the bigger issue -- what institutions do we have in place to protect OSS software effectively as small OSS devs? Do such institutions work? In this case, thus far, they don't seem to be working.

Comment Re:Search engines? (Score 1) 4

Actually that's not true. With the AJAX Crawl Spec, search engines can read AJAX pages.

http://code.google.com/web/ajaxcrawling/docs/getting-started.html

Basically, it rewrites domain.com/#!/someajaxstate to domain.com?_escaped_fragment_=someajaxstate, and then it's the responsibility of the server to render it statically. PhotoFloat uses HtmlUnit to do serverside javascript execution. I wrote about it here: http://blog.zx2c4.com/589 .

Comment Quality? (Score 1) 69

The big question for me is this--

The download link only allows you to get the encoded FLV file. Does this mean they failed to store the originals? And if this is so, does that mean YouTube would be serving up the old fashioned h.263 FLV low quality encodes? If that's the case, we'd be much better off _not_ using the auto-move service, as YouTube encodes at much higher quality than Google Video did.

Or, did they just not want us to be sucking their bandwidth by allowing us to download the original footage, but they'll happily transfer it in-house over to YouTube?

Anyone have any pointers?

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