Managing Shared Passwords?

What's My Passcode asks: "At the company where I'm consulting, several of our systems are being moved from the internal network to the DMZ. When we were internal, we could easily agree upon the "one" root password that would unlock all these systems, or use a logical progression where the root password was a secret word paired/mixed with the box name. Now that we no longer feel it's safe to have just one password, how do we keep track of shared passwords? I have searched Slashdot, and discovered this past question, but it was aimed more at the individual remembering their passwords. I've also tried wading through a series of Google and other searches, but gave up after several hours of useless and missing links. We can easily control who has accounts on the box, and who can use su, but in order to su you still need to know that root password. Sudo and similar won't cover what we need to do."

"I'm curious what other folks have done. I know I could create a database and store all these things in there, but I'm not real happy about storing a database of passwords in case that box gets cracked (internally, which has happened to several servers already -- and it looks like one of the new businesses that Big Corporation bought is doing a little espionage), or in case one of the hardware guys finds it. (The corporation demands that hardware work be done by the hardware guys, OS work by the OS guys, and us application guys deal with applications.) The OS guys are comfy not knowing root, but I frankly don't trust some of the hardware guys, who will be the ones taking the boxes offline at regular intervals for preventive maintenance. The OS guys all rely upon phyisical access to the box, and they keep a sheet of paper locked up with all the passwords scribbled on it.

I've also considered a Palm Pilot db, with encryption, but the ones I've tried all are aimed at personal password management, and some are cranky about being beamed around, even with L0pht's beamcrack.

Comments

Password safe

[dkusters]

Try out Password Safe available through Counterpane. It's from Bruce Schneier's company. Bruce Schneier is the author of Applied Cryptography, Secrets and Lies, CryptoGram newsletter, and the blowfish and twofish algorithms (one of which was an AES finialist). He has personally code audited the software, so I trust it.

Have one password for the Password Safe and have it store the root passwords for your other computers. If you are very paranoid, keep the database on a floppy and lock the floppy in a safe when not in use.

One downside, only Windows. But, a Linux version is coming Any Day Now (tm) (it'll be Open Source to boot!).

Dave

One time passwords

[whydna]

What about one-time passwords via S-key. The way it works is:

The system has a root password (which everybody that needs access can know). When you log in, you're presented with a phrase. On /your/ computer (not the server), you enter that phrase and your password (from above). This program generates a password that can be used ONCE!

So, no matter who's sniffing, anybody can see the exchange, but the password remains private. Do a search for "S-key" or "one time password".

Personally, I don't see what's wrong with require SSH. That /should/ be fairly safe.

Keyring for PalmOS

[jfunk]

check out Keyring for PalmOS

It used to be called GNU Keyring. I use it all the time. It's quick, stable, open source and all that other good stuff. It generates passwords for you based on settings you pick and works for encrypting notes as well.

That way you don't have to worry about your hardware guys sticking a disk in a password server and brute-forcing any data.

Before I had a Palm I used GPG to encrypt passwords. That's a decent solution, too, as long as you don't save a text version anywhere on your computer. I was also using loopback encryption for certain directories in my home directory. That way, even my private key, all of my encrypted passwords, and anything else sensitive is encrypted. If you're ultra-paranoid and you're the only user of your computer, you can loopback encrypt /tmp as well.

why not sudo?

[coyote-san]

Maybe I missed something, but why aren't you already using sudo or something similar?

In case you haven't heard of it before, sudo is a SUID program that gives you root access (or restricted root access, e.g., the ability shutdown the system or mount/umount disks, but no more) once you authenticate yourself with *your* password. You never use the actual root password.

Sudo also logs all commands executed. This can save you a *lot* of grief when you're trying to figure out what you did wrong.

Since each person must be named explicitly in a separate control file, it's easy to invalidate users as circumstances change. It's a lot easier to change one file on multiple systems than it is to get everyone to memorize new passwords.

As for the root password, I've found it unnecessary to provide *any* root password - just put a "*" in the /etc/passwd and /etc/shadow fields. The *only* place you really need the root password is if you're running in single-user mode because the fsck failed on boot - and in that case you'll probably want to use a boot/root rescue kit anyway.

If you want to keep a root password around anyway, it should never be routinely used. I personally favor the "write it on a card, put it in a sealed envelope, and (optionally) lock in in your boss's desk. Once you use it once, generate a new random password and repeat" approach.

As others pointed out, none of this will stop anyone from getting into the system their own root disk. But if fear of immediate termination doesn't scare them off, it's easy to remove the floppy and CD-ROM drives.

Re:why not sudo?

[lizrd]

Having a "Rescue" kit laying around is even more dangerous than having a root password.

I'm curious as to why you say this. It would seem to me that it's much easier to physically secure a machine in the DMZ than it would be to secure it from network attacks. If you don't keep your servers in a locked server room you need some serious help.

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PGP

[lizrd]

I'm going to have to agree with other posters here that you probably should be able to create a list of tasks that you actually need to accomplish as root and use sudo. If you're doing things that are greatly out of the ordinary your server probably shouldn't be online anyway. The solution of generating random passwords and placing them in a sealed envalope should cover your root password needs for any production server.

If however, you still feel that it is necessary to have the root passwords avaliable frequently you probably want to use PGP or GPG. Each person will have their own key/password to access the encrypted file. This makes it so that the "meta-password" is not shared and eliminates the need to publically post any changes to the passwords since they will always be found in 'the usual place'. You will also have the ability to easily add or remove people from the list to which the password list is encrypted. Overall, the safest way in which a database of passwords could be kept on the computer.

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Go Low Tech

[ScuzzMonkey]

Get a piece of paper. Write the passwords down. Lock it in a fire safe. People who need it and some other responsible authority who is easily contacted have the combination or key.

This sort of thing is desirable for disaster recovery, anyway--I keep a copy in the company safety deposit box, in addition to the one on-site. It's not particularly good to write passwords down, anywhere, but I'm in a similar situation and there are enough of them that there just isn't much choice. But far better to keep them off-line than use some of the techie solutions presented here. They're not susceptible to remote compromise and there's little chance of your piece of paper head-crashing or getting zapped with static electricity and losing all the information.