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How the NSA Took Linux To the Next Level
An anonymous reader brings us IBM Developerworks' recent analysis of how the NSA built SELinux to withstand attacks. The article shows us some of the relevant kernel architecture and compares SELinux to a few other approaches. We've discussed SELinux in the past. Quoting:
"If you have a program that responds to socket requests but doesn't need to access the file system, then that program should be able to listen on a given socket but not have access to the file system. That way, if the program is exploited in some way, its access is explicitly minimized. This type of control is called mandatory access control (MAC). Another approach to controlling access is role-based access control (RBAC). In RBAC, permissions are provided based on roles that are granted by the security system. The concept of a role differs from that of a traditional group in that a group represents one or more users. A role can represent multiple users, but it also represents the permissions that a set of users can perform. SELinux adds both MAC and RBAC to the GNU/Linux operating system."
Until we have a free government, I cannot see how anyone can trust software that comes from the NSA.
Long ago, in the days when MLS was just the holy grail, Harris Corporation created the first A1 rated Multi-Level Secure computer system. I can't recall the name given to it, BlackHawk or something overblown like that. It was secure, but utterly unusable. According to some early testers I knew, it took more than 10 minutes just to log on. The command line took, on average, 5 minutes to respond to the simplest command. There were no policy templates, so all permissions and access lists had to be entered manually.
SELinux doesn't look quite so bad in that light, now does it?
Yeah, yeah, yeah and it took years to calculate by hand before computers and months to travel any distance before airplanes. So what's your point?
SELinux is a pain in the ass. Your comparison is meaningless.
> Everyone who matters has always just called the OS "Linux".
Of course including the Debian people, who made one of the greatest distros so far?
(NOT the greatest, but certainly one of the greatest)
Why not just fix the silent failure? I don't understand this mentality of "There's a bug in the system! Scrap the whole thing!"
if you believe that selinux is "an utter pain in the ass" then you have misunderstood what selinux is for. selinux is specifically designed to be able to PROVE that an application is secure, using formal mathematical analysis (of the policy files).
... even ... remotely worth considering.
[ the principle on which selinux works is that when you change "security context", it doesn't matter a damn if you were "god" before, you're now starting from scratch with zero permissions in the new context unless otherwise specified. this is best illustrated with an example of when you go into a military environment, they take your ID badge away from you and issue you with a temporary one that is only relevant inside that building. you can't even leave the building without that temporary badge, and it's been coded to only let you go to the toilet and into the rooms that are associated with your specific purpose for being in that building. and of course, if you forget to get your permanent ID back once you _do_ leave, you'll find it very difficult to get out the country! ]
one of the "rules" that GCHQ and the NSA follow is that it is perfectly acceptable for something to be "insecure" as long as you KNOW that it's insecure: you can then provide a workaround or a fix to ensure that the security vulnerability is never exploited.
the one thing that you absolutely absolutely must not ever have is a situation where you don't KNOW whether something is "secure" or "insecure".
so if AppArmour has wonderful automated rulesets that are impossible to analyse...
the thing about selinux is that policies require that you understand the source code and what the application is doing. for example, one of the guidelines is that applications should use exec rather than fork, because that provides total privilege separation, obviously, between tasks. fork() does not provide such a complete level of privilege separation, and so up until quite recently there was absolutely no way in selinux to even step into a separate security context on a fork() - it just... wasn't
however, it turns out that there were some specific instances why stepping into a different security context on fork() is actually useful (such as in samba) and so it was added in. due to the circumstances under which this could be thoroughly abused, it was decided that it should be provided only via an explict selinux function call (usually, you can just provide an selinux policy statement without any code modifications).
How many people have looked through all the lines in a recipe and understand all the chemical reactions? Seriously, whats with people having faith in how somehow someone wouldn't slip in something that would be poisonous that the maintainers of the recipe wouldn't notice? Compare recipe to SELinux and you get the general picture.
And why would Debian, Red Hat, Ubuntu, and Fedora have it if it were malicious? Despite the fact that the US government could have made Red Hat put it in for Red Hat and Fedora, that still leaves Debian which is community (and is quite good about making sure its systems are secure) and Ubuntu which is based in the UK and is community much like Debian.
Sure, healthy suspicion is good, but really, its just as stupid as saying because not everyone knows what the chemical reactions are when you are cooking it suddenly leaves you open to poison yourself with it.
Taxation is legalized theft, no more, no less.
If no one's using it, how will it become mainstream?
Big difference: Windows was designed to be a complete OS in its own right, but Linux was specifically intended to be combined with the GNU software to form a complete OS.
I can't deny that I normally call the combination "Linux" myself, but I don't understand why some people are actively hostile to the concept of calling it "GNU/Linux" instead.