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Comment Re:Now, if... (Score 0) 280

For a single user, sure, the text editor is nice and easy. Now how about a multi-user box with a few thousand of them? You can do some grep -v stuff, but now you need to think about concurrency (I bet one of your users will be editing the file at the same time as your automated sweep). And so now you need locking, but your text editor won't lock the file that you open by default, so now what happens? This is part of the reason wrappers like vipw and visudo exist: so that you don't get update races (sanity checking is the other reason).

Comment Re:Yeah (Score 4, Interesting) 280

I have a lot of respect for most of the OpenBSD team, but Theo is definitely trolling here.

Let's start with the premise of TFA, which cites the article on Ars that was covered here a few days ago and was complete nonsense about the new random number infrastructure in FreeBSD. We are not moving away from using the hardware random number generator directly, we have never used the hardware random number generator. The new code that the Ars article was talking about is to allow the PRNG to be easily switched. In 10 we're shipping both Fortuna and Yarrow and the infrastructure allows more to be added. The code has been reviewed by two cryptographers that I know of and possibly others. Neither the old nor the new implementation is vulnerable to the attack against random number generators that was published a couple of months ago (Linux was the subject of the paper, not sure if OpenBSD was vulnerable).

If Theo is going to make such remarks as this, he should think more carefully first:

"Basically, it is 10 years of FreeBSD stupidity. They don't know a thing about security. They even ignore relevant research in all fields, not just from us, but from everyone."

He'd be advised to take a look at the transactions for the IEEE Symposium on Security and Privacy over the last 10 years and see how many papers are describing techniques that were both originally implemented on FreeBSD and are now part of the default install. Let's take a look at the two systems, from a security perspective. Both FreeBSD use SSP and non-excutable stack by default, so I'll skip those. To begin with, OpenBSD features missing on FreeBSD:

W^X enforcement. Definitely a nice idea, but it breaks some things (JITs mostly). The default memory map in FreeBSD is W^X, but it is possible to explicitly mmap() memory both writeable and executable. It's generally considered a bad idea though, and we don't ship any code that allows it. We permit third-party code to shoot itself in the foot if it really wants to and provide mitigation techniques to reduce the risk.

Then there's ASLR. This is a pretty nice technique, which is currently not implemented on FreeBSD. We do support PIE, so it would not be a horrendously difficult thing to add, but current implementations (including OpenBSD) use a surprisingly small amount of entropy in the address layout and so don't provide as much mitigation as you'd hope (which, of course, Theo knows, because he's very familiar with 'relevant research'). This is especially true on 32-bit systems.

And that's it for OpenBSD. Well, unless you want to count , but since that's vulnerable to a timing attack (still not fixed), which was published in the USENIX Workshop on Offensive Technologies, and Theo is aware of all 'relevant research' in security then it can't really still be there.

Now let's look at FreeBSD security mechanisms:

First up, jails. Jails are somewhere between a chroot and a VM: a shared kernel, but all of the global namespaces (filesystems, IP addresses, users) are separated and so you can completely isolate a service, such as a web browser, from the rest of the system. Scripts like ez-jail in the ports tree make it easy to set up lightweight service jails.

Then there's the MAC framework, which allows modular access control policies. This is used by a couple of FreeBSD derivatives: JunOS uses it to implement code signing, OS X and iOS use it for application sandboxing. You can also use it for traditional type enforcement policies, as in SELinux and a variety of other things.

And then there's Capsicum, which adds a capability model on top of the traditional UNIX file handle model. A process can call cap_enter() and then can't create any new file descriptors, it can only use the ones it has and receive others from a more-privileged process. A number of things in the base system now run in sandboxed mode by default and so a compromise in any of them is contained.

There's also some simple stuff, such as support for both POSIX and NFSv4 ACLs (OpenBSD has no ACL support). If you really care about security, then you probably also care about checking that your system is secure. FreeBSD provides auditd (which records auditing events from the kernel) and auditdistd (which distributes them in a cryptographically-secure, tamper-proof way to other machines). OpenBSD provides nothing comparable.

I could also talk about the fact that FreeBSD signs packages and distributes the signatures via a different mechanism to the package retrieval, whereas OpenBSD still distributes them via FTP with no signatures. Or how FreeBSD provides the pkg audit command (run as part of the daily security check and emailed to root by default) to check for known vulnerabilities in installed packages and provides updated packages throughout the life of a release, whereas OpenBSD requires you to compile everything from ports if there's a security advisory (great on that 200MHz Soekris board that's your firewall), but since that infrastructure is quite new in FreeBSD I won't talk too much about it.

Comment Re:Do these projects OpenBSD, FreeBSD matter anywa (Score 1) 280

Netflix is a nice example, but if you use the Internet the first thing you probably do is use DNS. Verisign's root servers and the TLD servers that they run all use a 50:50 mix of FreeBSD and Linux (diversity is important, because if there's an exploit for one then they can just turn that one off until it's fixed. They also run different resolvers and so on).

Comment Re:Framing the debate (Score 1) 280

I'd take issue with your second point. All binary updates using freebsd-update are signed and that mechanism is used to distribute the signing keys for packages. When you do 'pkg install' on a recent FreeBSD system, it will bail if the packages don't match the signature. We also have a revocation system in place that allows us to easily revoke keys if the package building system is compromised. We just received a large grant from Google to work on package transparency, a mechanism akin to certificate transparency that allows you to validate not just that your packages are signed, but that they're the same packages everyone else is getting. We do have deterministic builds for the base system (they're needed for the binary update mechanism to work), but not currently for ports - that's something we're working on though, as it's a prerequisite for package transparency.

The authoritative repository is svn, but there are numerous git mirrors, and we did use them to validate svn after the compromise last year. svn is actually not that hard to audit, but cvs (which OpenBSD uses) is a nightmare - we gave up trying to audit it and just re-exported the cvs mirror from svn.

Comment Re:Rule #1 (Score 3, Insightful) 894

Did you know that with some kind of explosive (preferably one that you can remotely detonate) and some coins (easily available) you probably can kill or severely injure a lot more people than you can with a firearm? The ensuring explosion is like a frag grenade, except you can make it a lot bigger and lethal. Bonus points for triggering it in a cafeteria o some other kind of eating place with lots of people.

As another poster said, this requires a lot more premeditation. A nail bomb is pretty easy to assemble with ingredients that are readily available in most industrialised nations, but doing so requires (at the very least) a few hours of work. If you want timed detonation, that's more thought and planning, and you need to be quite calm while building the bomb or you're likely to just blow your hands off. Most people, by the time they've even got as far as thinking through how they'd go about blowing up their school will have calmed down enough to realise that it's a bad idea.

In contrast, if a gun is readily available then you just need to pick it up and, while still angry, got back to the school and start shooting. You don't need to think hard about what you're doing. That's one of the rationales behind laws that require a 24 hour or 7 day period between ordering a gun and getting it - if you want to kill someone in cold blood, you'll find a way of doing it with or without a gun, but if you're thinking of doing it because you're stressed or angry, then there's a good chance you'll have changed your mind by the end of the cooling off period. Of course, if you go ahead and buy the gun, there's nothing to stop you the next time you get stressed...

Comment Re:Very Smart Move (Score 1) 178

It depends on the implementation. As I recall, the Intel ones are basically just a pair of flipflops in an unstable configuration for each bit. They're intended to be something that toggles between 0 and 1 at some frequency that you can't easily determine (and which isn't the same for each bit). However, as they're digital circuits, they do respond to heat. Hopefully, they don't respond in a way that makes the readings more predictable, but it would take a lot of analysis to be sure of that.

Comment Re:Still won't fix monopolies (Score 1) 153

In the UK, this is referred to as Local Loop Unbundling (LLU), and it was promised to bring in more competition. It does, to a degree, but installing the equipment at the exchanges is very expensive. They're also BT was forced to separate its wholesale and retail businesses into separate business units, and provide the lines at the same price to competitors as they provide to their retail business unit. There are several problems with this though. If you buy broadband via this latter option, you need to pay line rental to BT Retail, which is stupidly expensive (around £15/month, and then calls on weekdays cost more than I pay from my prepay [no line rental] mobile phone) and bumps up the profits of BT Retail. There's then no requirement for BT Retail to make any profit on broadband, and so they can afford to undercut competitors who actually need to make a profit.

Comment Re:kind of ruins the point....... (Score 1) 308

A good paper is not necessarily a paper that will win a Nobel prize. If you're just sitting there and thinking really hard, hoping for inspiration to strike, then you'll have difficulty doing this. For everyone else, you always have intermediate results that give you something useful and it's incredibly valuable to share these with the wider community so you don't end up with everyone doing the same work in secret. If you can't manage to publish at even this rate, then you are being far too secretive about your work to justify an academic position.

Oh, and it's not once a year, it's once a year on average, over four years. So if you work on a big project for 2-3 years and then get a flurry of papers out at the end, then that's fine too.

Comment Re:meeses (Score 1) 361

I used to have one that detected the motion of the ball by shining a light down the a cylinder that the ball rolled. This made it very accurate, but it had the down side that in bright sunlight enough light got through the white plastic to permanently trigger the sensor, so it never saw an occlusion and thought that the ball was stationary. A nocturnal mouse.

Comment Re:Scottish Independance (Score 1) 208

Given the northward flow of tax money in the UK currently, Scottish Independence would mean that the government of the rest of the UK could immediately end all of the austerity cuts. Meanwhile, the Scottish government would be trying to get comparable handouts from the EU (likely vetoed by Spain so that Catalan independence doesn't get any inspiration), or watching the economy tank. All of the benefits that Scotland gains from large proportions of the military being stationed there in peacetime would evaporate, as would the public sector contracts that have been helping to bootstrap the Scottish IT industry over the last few years.

Comment Re:So, same as the Linux Kernel (Score 1) 178

You might want to check your facts. A few things:
  • The new FreeBSD randomness framework allows whitening algorithms (Yarrow, Fortuna, whatever) to be plugged in easily, along with multiple sources.
  • Linux initially trusted RDRNG unconditionally to provide streams of random numbers, then backtracked to only using it as an input to whitening. FreeBSD only ever used it as an input to the PRNG and now has a more generic framework for doing so.
  • Neither the new, or the old, FreeBSD random number generation framework is vulnerable to the attack published in October (and covered on Slashdot) on the Linux random number generator.

Comment Re:Weird stance. (Score 2) 178

Trust in a random number generator is not a binary thing. All of the current hardware RNG implementations produce some entropy. The question is how much entropy you trust them to produce. If it gives 256 bits of entropy, then you can just use it as your random number source and be done with it. One that produces 16 bits of entropy is very useful as one (but not the sole) source to an algorithm like Yarrow of Fortuna, but would be a disaster if you used it as the random number generator without such an algorithm in the middle.

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