Gentoo Archives: gentoo-server

From: "Jesse
To: gentoo-server@l.g.o
Subject: RE: [gentoo-server] forcing good passwords
Date: Wed, 18 Jan 2006 16:40:40
Message-Id: FB5D3CCFCECC2948B5DCF4CABDBE6697545D15@QTEX1.qg.com
1 With all this discussion of passwords, there's some very important
2 points to be made:
3
4 -- Environments where passwords are required vary widely.
5
6 Some will have more computer-saavy users than others, but even
7 within those environments there will undoubtedly exist an element of
8 "duh". Read Computerworld's daily SharkTank for examples.
9
10 -- Passwords too complex for your users to *easily* remember defeat the
11 purpose of having the password.
12
13 If passwords are unnecessarily complex, the user will either
14 constantly forget them, causing reduced productivity at best, or write
15 them down, subjecting the password to theft. In HPUX using their
16 Trusted System option, the SAM program generates a 30 (*THIRTY*)
17 character password for new accounts. What's the point??? There's no
18 way to remember the jumble of characters that long and it's not easily
19 sent to the user electronically so it must be written down and is then
20 immediately subject to being stolen or just plain lost on the way back
21 to their desk or whatever.
22
23 -- If multiple passwords exist on multiple systems, give the user a
24 mechanism to change/expire all at once.
25
26 In my experience, users don't know (and shouldn't have to!) why
27 and how they have different accounts to do their different tasks.
28 Ideally, they should have one account with one (possibly two for extra
29 security) easy-to-remember password. If not, this will confuse many
30 users and make their life (and consequently, yours) more difficult.
31
32 So, what to do? Glad you asked! At a DECUS (now-defunct DEC User
33 group) meet back in '92, a chief security guy recommended these:
34
35 1) 30 day lifetime
36 2) Minimum length of 12 (eep!)
37 3) No reuse of passwords (keep password history)
38 4) Check password for dictionary and common variants (e.g. username)
39 5) Do not use system-generated passwords
40 6) Teach users to use an algorithm to generate passwords.
41
42 The last one is the kicker that makes the rest easy. The guy from DEC
43 said to take two of your favorite things, in his example, beer and Star
44 Trek. Combine elements of the two to get your password, for example,
45 "spockmiller". To meet system requirements and make the password
46 incredibly more difficult to crack or guess, duplicate letters and add
47 numbers: "miller23spockk". The password is now easy for the user to
48 rememeber, easy for them to think of new passwords every month, and
49 generally about as secure as passwords can get. Of course, I use my own
50 variant on the above as an added measure of security to help discourage
51 others that know this method from attempting to guess my password. :)
52
53 This solution is not generally one of server management, but of user
54 training. The first five items can be enforced. The last one is how to
55 make it easy (easier at least) for the user to abide by those rules in
56 order to help keep your data secure.
57
58 Not that I know how to implement any of this in Gentoo... :)
59
60 Thoughts, comments, questions? Holler!
61 Rich
62
63 --
64 gentoo-server@g.o mailing list

Replies

Subject Author
Re: [gentoo-server] forcing good passwords "Paweł Madej" <linux@××××××××.info>