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Would You Use SELinux?
silent_tyr asks: "I am going to re-install my Linux box and being security conscious I am looking for a secure distribution. After a couple of Google searches I found a version called Secure Linux, which sounded ideal. So I followed this link, which turned out to be what I assume is a genuine NSA web-site. All in all, it looks like a good idea and I can play around with it as I wish, but eventually I will be using this machine as my base-system. So before I start I want to ask two questions:
1) Do you think that it is a good idea to trust the NSA not to put in back-door/spy-ware type code to enable them to snoop my personal information? 2) What other security-patched distro's can people recommend? I don't want to open up the floor for generic NSA-bashing, but I also don't want to have to work my way through every line of code before I install." There was a similar question that was asked a while ago, but there wasn't much to the discussion. For those of you who are running SELinux, what have your experiences been, so far?
Holy Welcome to Last Decade, Batman.
Just install Windows XP like everyone else. Stick the free version of ZoneAlarm on there, and you will be as secure as any box out there!
Slashdotter are stupid and biased.
Do you think that it is a good idea to trust the NSA not to put in back-door/spy-ware type code to enable them to snoop my personal information?
Am I mistaken, or is SE Linux not a source distribution?
GPL'd source guarantees that nothing lives in your kernel that you cannot examine as much as you like for backdoors.
It's a powerful guarantee, one that cannot be made of many commercially produced operating systems, whether they are called "secure" or anything else.
"Provided by the management for your protection."
Check out EnGarde Linux.
Also, LinuxSecurity.com is a very helpful and informative site.
Co-founder and designer at Music Nearby: http://musicnearby.com
grsecurity
LIDS
As far as the NSA planting a back door into SELinux, I really doubt it. A backdoor in open source code would be discovered eventually, and the NSA would have a very hard time denying it.
It seems much more likely that they would put back doors into closed source products, which do not receive as much scrunity.
IIRC, it's a series of kernel patches and some modified basic utilities. I wouldn't be surprised if there was more to it than when I first looked at it a couple of years ago.
;) amount of work?
But as to NSA backdoors, honestly, how much intel would they gather from the handful of people who would install SELinux? Wouldn't it make way more sense to crack into Microsoft's source code (if a Russian hacker could do it, well, I'm sure they can) and do it in a closed-source, widely adopted OS?
Hey, I'm as much a conspiracy theorist as the next mildly-intelligent person who sees strings pulling the marionettes in our government. But it ultimately comes down to a resource allocation issue. Why bother when there's so much more to be gained with the same (or less, if you consider the need to somehow disguise the backdoor in open code!
Now about those microwave towers...
Amateurs discuss tactics. Professionals discuss logistics.
I personally have a great deal of respect for the folks at the NSA. I am also quite aware of their abilities, and let me say this if you are going to hand teh keys to your system to any one organization you might as well hand them over to the NSA becasuse they already have them.
Seriously I work in the security field, and have worked closely with all kinds of govt. operatives from local, state national and even foreign groups in my various and sundry dealings. Nobody and I mean NOBODY has the smarts/ ability / computational facilities as the NSA. The only other group I hold in such extreme regard is Mosad
Bad Panda! No Bamboo for you! In matters of importance ACs will not be responded to. Want to say something critical,OK
IMO, the bigger question is: "will the extra security measures get in the way of doing what you need to do?" And probably the corollary: "If you're going to have to disable any of those features, is it still worth using this distribution?"
Check out my eclectic infosec blog at InfoSecPotpou
Hum, so you ask us, who you don't know, which developers, who - in most cases - you nor we know either -, to trust? Maybe you are an NSA agent in search of backdoor-free distributions? Why should we trust you, sir?
Seriously, short of a full code audit, you can never be sure. Security is a process, and not something you can install. I thought that was commonplace around here.
--
"Just believe everything I tell you, and it will all be very, very simple."
Does it -have- to be Linux?!?
SDF (the free shell-provider) switched -from-
Linux... after a security breech...
OpenBSD is claiming to have had:
"Only one remote hole in the default install,
in more than 7 years!"
That's not too bad IMO.
And... if you -really- itch for Linux...
you can always put it on a box -this-
side of an OpenBSD box (ie away from
the Internet...)
First off, which is more likely- that you have information that the NSA is curious about on your machine or that some random loser with test it for various vulnerabilities? If I remember correctly, the idea behind the NSA distro was to provide a free, secure solution to slow or stop the DDOS attacks and the like. If you have anything that the NSA would REALLY be interested in, other then a pron stash that everyone else has, (meaning actual illegal, get-you-jail-time stuff) why on earth would you put that on a machine conencted to the internet? Put it on a separate machine behind a firewall and encrypt it if you are that concerned about it.
It's been my experience that Linux is Linux, regardless of what distro you use or how you install it. You get different package management tools, varying versions of libraries, and better or worse optimized binaries. But the bottom line is that once you take the time to secure it, the various distributions really are not very different from each other. I think the important thing is to trust yourself and not the vendor. Regardless of how secure a server is, it's still your responsibility to change default passwords, disable services you don't use, stay up to date on security patches, and be aware of new exploits. When you keep this in mind you can really go with your distro of choice and get the same results. I'd recommend selecting a distro based on the package management and support options you want.
% man diff
GCHQ Quantum Insert installed. If only our tongues were made of glass, how much more careful we would be when we speak
If you *really* think that NSA planted backdoors intending to gain intel on people who installed it, would the people they want information on install it? eg - would al Quida peeps install it? How about the (pre-war) Iraqi Military? Would they install if there was speculation over backdoors? Answer - no.
Therefore - it would be a waste of effort, time, energy, and money for the NSA to plant a backdoor in something they make publicly available. Besides - its frickin open source!! Check the code yourself - or check one of the many websites that have information about it - you'll also find one group that has completed an independent audit (looking for backdoors, trojans, etc). Guess what they found? None.
(I'll leave the searching for that report to the poster who appparently feels threatened by backdoors but cant do a google search.)
After exaustive code riview of the LSM patches I have discovered a backdoor in the PAM module re-write lin...
excuse me, there's some at the door. brb.....
thers no suh thig as backdoor in seLinux, he was joking.
In teh event of an actual emergency this space might provide useful information.
The moral is obvious.
You can't trust code that you did not totally create yourself. (Especially code from companies that employ people like me.) No amount of source-level verification or scrutiny will protect you from using untrusted code. In demonstrating the possibility of this kind of attack, I picked on the C compiler. I could have picked on any program-handling program such as an assembler, a loader, or even hardware microcode. As the level of program gets lower, these bugs will be harder and harder to detect. A well installed microcode bug will be almost impossible to detect.
There are places where the networks are not touching,and there are places where they are-Boeing's Lori Gunter
NSA publishes the source to SELinux. If they put a backdoor/whatever in it, there would be lots of fuzz about it by people who know what they are talking about by now.
My understanding is that SElinux is more about mandatory access controls, that is enforcing security between multiple individual users.
More along the lines of breaking the dependancy to give elevated privs (admin) to get anything done on a machine.
The BSD's may have the features that a person needs in their applications.
SELinux is directly supported under Gentoo.n ed/selinux-qui ckstart.xml
See
http://www.gentoo.org/proj/en/harde
for details on installing.
Or dig on the mailing lists for a recent post to gentoo-dev about it for a lot more information.
ICQ# : 30269588
"I used to be an idealist, but I got mugged by reality."
Though you expressed it with humor, the point is very valid. Doing a diff on to kernel source trees that kicks out 50k lines of code sounds like reading enough, but in many cases of a 10 line change, you'll have to read a good chunk of the rest of the module to get the proper context.
/. this question, you have no chance in hell of catching them.
Additionally, all this is in the realm of seriously expert shit. If the NSA put in a backdoor like
if (connecting_socket->IP == 152.63.39.37) {
connecting_socket->priv_level = GODLIKE;
}
You're in luck.
In most other cases a backdoor is just a hard to exploit/spot vulnerability like a stack overflow, or an awkwardly cast variable assignment that allows the tricky person to assign values to the target varible that are outside it's normal range and have a desirable side effect. If you wrote the modules in question these things would be noticable, if you're a full time kernel coder, they would be possible but hard to spot. If you're asking
The Linux From Scratch suggestion above seems like the most user accessible way to go. I would trust the good will and intentions of individuals over any government's institutions every day of the week.
About the NSA:
It coordinates, directs, and performs highly specialized activities to protect U.S. information systems and produce foreign intelligence information. A high technology organization, NSA is on the frontiers of communications and data processing. It is also one of the most important centers of foreign language analysis and research within the Government.
It's actually in their public duty to create something like SELinux. If you go to their front page, they have links to many guides on how to secure various Windows and Cisco systems. It's seems really surprising when you think about it, but they actually want to protect the United States.
Sounds like a lot of you people are doing things the NSA might be interested in. I could email every file I've ever touched to the NSA, and they still wouldn't care to notice me.
If I did have stuff the NSA might be interested in, I sure would not put it on a computer that was connected to the internet.
I metamoderate, therefore I am
From their FAQ:The download should verify this. In fact, I downloaded the patch to the 2.4.20 kernel, and it topped out at just over 40,000 LOC changed, including what looks to be a good amount of documentation. While that's a decent chunk of code to review, it's not the 5,399,647 LOC (I just counted) that go into the 2.4.20 kernel itself.
So if you're really paranoid, go check it out.
Yes, given that...
Now, granted, a backdoor could exist, but it could equally well exist in any other distribution. If you want to be a conspiracy-theorist, there is little reason to believe they haven't already forced Linus or anyone else to accept some patches, or even installed them in gcc, as explained Ken Thompson's excellent article.
2) What other security-patched distro's can people recommend?
I have no idea. My guess would be that there are a lot more people writing security patches for linux, then there are people reviewing them, so I doubt anyone else knows much about this either. Everyone will probably recommend their own patches... :-)
For maximum security i would use another box as a firewall. I think it would help when the firewall box has another operating system as the workstation. Of course a linux firewall box is better if you run windows. If your workstation runs linux your firewall box should run windows. That will confuse the attacker.
Debian also includes SELinux, and the "details for installing" seem to be: 'apt-get install selinux'. :)
So, that's at least two major community-oriented distros that have found SELinux worth offering on at least an optional basis; two communities of sometimes-paranoid developers that have probably at least scanned for obvious backdoors. Given that, I suspect that SELinux can probably be considered reasonably safe. (At least as safe as anything else available with your system: when was the last time you reviewed KDE or GNOME for potential backdoors?)
It is nsa.gov, and you had to ASSUME it was legit? do you think our spies have a sense of humor or something?
The NSA has done a lot of reputable work on building trusted systems - if I recall correctly, it was the NSA that published the Rainbow Series. I worked on an NSA-funded project to develop a trusted OS (Trusted Mach) for several years.
There seems to be several distinct groups within NSA. The infosec guys are generally ok; so are the foreign intel linguists. It's the crypto people who worry me.
I would trust an open source OS from the NSA. I would have some trepidation about a closed source one. I wouldn't use a crypto algorithm designed by them for anything interesting.
Tom Swiss | the infamous tms | my blog
You cannot wash away blood with blood
Being a little paranoid about NSA putting sneaky code into their own little obscure distribution isn't justified. Why would NSA backdoor something almost no one will use?
If the NSA wants to get a backdoor into Linux, there are easier and more traditional ways to do it. A sufficient amount of money passed to the appropriate developers and commercial Linux vendors would do the trick quite nicely.
-- Slashdot: When Public Access TV Says "No"
after running /sbin/rmmod nsakey
I use SELinux. I've read through all the modified code. I'm not the first one to do so. It's not backdoored. It works.
By the way, do you trust that Microsoft doesn't have backdoors put in? If not, then do you trust the big Linux distros? If you trust either of those, then why are you so suspect towards the NSA patches?
http://selinux.dev.gentoo.org/ runs gentoo SELinux.
Simply ssh into that machine as root (password is gentoo). It's uncanny. You can't see the apache processes with "ps". You can't do much, really. It's probably too secure to be useful as a workstation, more of a single-task production server.
I'm glad I tried it, but I certainly won't be using SELinux, I should try all those grsecurity options at the bottom of the kernel config some time though.
Note to ACs: I won't mod you up, even if you are being funny or insightful. So take a chance! It's not real life!
A sufficient amount of you shutting the fuck up would also be quite nice.
You have to keep the policy of your SE Linux installation up to date and customize it for your needs. I've found, it's a time consuming job to do so. If you haven't too much time, I would suggest to wait, until there is a tight default policy for more packages and it is integrated in the actual stable linux kernel. Also SE Linux is only a small part of security. For the average user, a personal packet firewall, JavaScript and co. filter and stack smashing protection (e.g. supported by Open BSD AFAIK), should be more helpful.
Security is all about modes of failure.
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Start with the assumption that all software has vulnerabilities.
Given enough resources everything is vulnerable.
Properly implemented SE linux reduces the risk of byzantine failure of the system.
Most people tend to think of layered security as being effective. SE linux allows the implementation of an encapsulated security policy, think of the internal structure of the pomygranite. IBMs gcc patch is also a good step in this direction however this merely eliminates a class of failures and doesn't make your system immune from attacks. http://www.trl.ibm.com/projects/security/ssp/main