Gentoo Archives: gentoo-user

From: Bill Longman <bill.longman@×××××.com>
To: gentoo-user@l.g.o
Subject: Re: [gentoo-user] Rooted/compromised Gentoo, seeking advice - AKA passwords
Date: Thu, 12 Aug 2010 05:04:16
Message-Id: AANLkTin3VgV2ti9uR7opO2FogqtsJk4pkWCkitRbyLMc@mail.gmail.com
In Reply to: Re: [gentoo-user] Rooted/compromised Gentoo, seeking advice - AKA passwords by Alan McKinnon
1 On Wed, Aug 11, 2010 at 4:09 PM, Alan McKinnon <alan.mckinnon@×××××.com>wrote:
2
3 > On Thursday 12 August 2010 00:11:12 Bill Longman wrote:
4 > > On 08/11/2010 01:30 PM, Alan McKinnon wrote:
5 > > > I refuse to implement password expiration policies and have a vast
6 > array
7 > > > of literature to back me up when some dimwit damager gets on his
8 > > > expiration high horse.
9 > > >
10 > > > My users pick their own passwords - I present a list of 5 from apg and
11 > > > let them pick one. Accounts do expire if they go unused for 90 days,
12 > but
13 > > > not passwords.
14 > > >
15 > > > What put me onto this policy? I found Gartner recommending password
16 > > > expiration. I find the best security possible is always the opposite of
17 > > > what Gartner says. Discovering how the AD admins in the company go
18 > about
19 > > > their jobs was the convincing straw :-)
20 > >
21 > > The bigger buggerboo I see is the "password complexity" [il]logic.
22 > > There's this vapid requirement of all these different types of
23 > > characters needed in one's password, yet the thing you really want to
24 > > enforce is adequate entropy. If my password is an entire sentence, it
25 > > will not be brute-forced, even if I used just ASCII A-z. There's just
26 > > too much key space in 4.7^32. At 10^5 attempts per second, you're likely
27 > > to find the answer in half a billion years. I hope your keyboard still
28 > > works, let alone exists....
29 >
30 > Your reasoning makes sense, until you consider password length limits
31 > imposed
32 > by machines.
33 >
34 > Cisco routers authenticating via Tacacs for instance often support nothing
35 > more than DES hashing <yuck>. The hash routines accept up to 10 characters
36 > for
37 > a password but only use the first 8 to calculate the hash.
38 >
39 > There are Solaris version nowhere near EOL yet that have similar limits.
40 >
41 > All this makes my life as a system integrator cum authenticate go-to guy
42 > very
43 > tricky indeed. Luckily management tends to say "Just do what Alan says. It
44 > makes him shut up and go away".
45 >
46 > :-)
47 >
48 > p.s. dig the use of "vapid". Wonderful word, truly splendid. Communicates
49 > in 5
50 > letters something that takes paragraphs any other way. I shall make a note
51 > for
52 > future use.
53 >
54 > --
55 > alan dot mckinnon at gmail dot com
56 >
57 > Absolutely. If you do not change your ENCRYPT_METHOD or your PASS_MAX_LEN
58 in your login.defs file and are still relying on the back end's ability to
59 safely store your passwords in DES format, well, you're in trouble.