Re: Opportunistic signatures - a proposed design

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On Wed, 1 Sep 2004, Eric S. Johansson wrote:

>> 500 users minting stamps on 500 desktops is not a significant burden. 
>> 500 users having all stamps generated by an outbound "stamp server" 
>> could be.
>
> yup, that's right.  Unless of course the organization says "we're not 
> touching the desktop.  If you tell us to, go pound sand and have a nice 
> day." In my experience, this is any organization with more than 100 
> desktops.
===============

those organizations NEVER lead the way... they adapt reactively, not 
proactively. if they could get away with rotary phones, typewriters and 
carbon paper, they'd still be there.

so, those organizations ONLY adapt when they have to, and only to the 
extent that they have to. if/when hashcash becomes a universal standard, 
they will reluctantly adapt. maybe they'll spend 0.00000001% of their IT 
budget on a "stamp server"... maybe they'll wait until the next 10-20 year 
cycle when they're forced to upgrade their desktops... they're neither 
movers nor shakers... they'll follow what technology dictates they must, 
and they'll bitch and moan every step of the way. a public-key system will 
be greeted with the same enthusiasm.


> no, that is not what I am talking about.  I am talking about individual 
> signatures associated with a given e-mail address.  I was talking also 
> on the context of an enterprise or ISP environment.  The same technique 
> will also scale down to the individual user.
==========

except that individual users won't have an in-house IT staff providing 
24/7 support for their "network". if the fortune 500 companies can't keep 
from getting infected with electronic diseases, granny doesn't have a 
chance.

anyway, when i hear about an outbound server (since the desktops are off 
limits), that usually involves keys per site, not per user. i suppose they 
could configure it per user...


> Personal boxes will get more secure.  They are significantly more secure 
> than they were five years ago.
=========

that's debatable. i'm guessing that you don't subscribe to bugtraq, risks, 
or crypto-gram. the way i see things, it's getting worse every day.

how secure is this: Zombie PCs spew out 80% of spam 
http://www.theregister.com/2004/06/04/trojan_spam_study/

read that article, and think about what impact hashcash would make vs what 
impact signing keys would make.


> Continuing to dither about stolen keys due to viruses and other 
> intrusions will only serve to keep security off the desktop.  If there's 
> nothing there to protect, why protect it.  As soon as there is something 
> that to protect and a few people get burned, then they will be action on 
> many fronts to make the desktop more secure and quickly.
==============

if that were the case, bill gates would have been eating out of garbage 
cans and begging for change years ago. do you have any idea how many 
password-stealing viruses there are? they're coming out faster than they 
can be added to anti-virus software! the whole paradigm of M$ is like 
whack-a-mole... they'll never win... they'll only get further behind...

there are things on desktops that need to be protected, and every time 
they get stolen or destroyed people just shake their heads and throw their 
arms up.


> If you're going to continue to dither about this, you might as well bend 
> over, grab your ankles and say "I'm ready for my close-up Mr. intruder" 
> because there isn't going to be a solution that is either practical or 
> one that will make you happy.
===============

freeBSD makes me happy. linux makes me happy. the thought of bill gates 
eating out of a garbage can makes me happy.


>> i would assume that a machine gets owned, and between 2-3am that night 
>> the spam will start... send out a flood of spam while the mark is 
>> sleeping, and when they wake up they'll have a lot of people ~very~ 
>> angry at them.
>
> see my point above.  If there's something to protect, the people will 
> demand some way to protect it.  It's not going to happen a minute 
> before.
==============

start reading crypto-gram.... one of schneier's repetitive points is that 
software manufacturers should be liable for damages caused by their faulty 
software. that would create an incentive to create better software.

viruses have been blamed for everything from bank failures and railroad 
delays to power outages that spread through several states. if THAT'S not 
enough to light a fire under someone's ass, i don't know what is.

since the average user's desktop CAN'T be kept secure, i really think 
personal keys on auto-pilot is a net-loss. signed spam is still spam.


>> agreed then: M$ is the problem ;)
>
> actually, computers or the problem.  It doesn't matter which OSes out 
> there, compromises will happen, people will get burned, lawyers will get 
> rich.
>
> in all this argument of risk factor vs. risk factor, one thing neither 
> of us can show is actuarial tables.  Until you can show that for a given 
> number of hours on the net running particular piece of software etc. you 
> have a 0.000x percent intrusion rate, all discussions of risk are just 
> blowing smoke.  100 percent fine Caribbean smoke.
============

anything related to computer security (M$ press releases excluded) will 
show a clear trend in what systems are more/less secure.

we have to assume that systems are insecure, and will remain insecure in 
the foreseeable future. given that assumption, i see no useful role for 
signing email on auto-pilot.


> when risks are categorized, people will demand protection analogs of 
> police, fire, insurance.
==============

the risks have been around as long as computers, and those analogs have 
yet to materialize. some companies have insurance, but that's tantamount 
to admitting defeat. as long as commercial software can hide behind 
shrink-wrapped indemnity clauses, they have absolutely no incentive to 
make things better.


> understood.  But the human factors aspect of dropping the cost of 
> hashcash and substituting a signature as a forgery resistant channel 
> between two parties, is hugely beneficial to the end-user. The reason 
> all security measures fail today is because of human factors.
============

yes... people are stupid. there are some incredible algorithms and 
protocols that ~can~ keep computers and data secure, but they provide no 
defense against a sticky-note with the admin password.

a password-less signing key on an inherently insecure computer is worse 
than the problem that it's trying to solve. and your theoretical 
organization will be just as reluctant to implement that system as 
anything else that involves writing a check.


> Why do we still use passwords?  It's because they suck less than all the 
> alternatives.
==============

hehe... try using the public-key feature of ssh.... that's way better than 
a password!


> Why is e-mail plaintext?  Because it's easier to use than trying to 
> remember a passphrase.  Why do e-mail and browser applications remember 
> passwords for you?  Because it sucks less than remembering passwords.
>
> so, we can go around this barn again or we can figure out a good, human 
> factors friendly way of minimizing stamp load when it is really needed. 
> This is important because a large number of attacks against hashcash are 
> political.  They are "I'm not touching my desktops", "why should I spend 
> stamp time every time I send a message to someone I know","what about 
> mailing lists", and a host of others.  They all appeared to boil down to 
> a resentment to spending CPU cycles unnecessarily.  but what they really 
> are is failures of human factors.  And when it comes to human factors 
> vs. security, human factors always win unless there is some dude with an 
> M-16 standing near you.
====================

all of those political arguments apply equally to a public-key system. 
well, except for the CPU load of minting a stamp... but watch your CPU 
meter next time you sign something, that's not quite free.

i understand that implementing hashcash could be a big and costly step in 
some settings... to those organizations i can only (in the most respectful 
way) give a one finger salute...

here's the deal, the way i see it; if you use hashcash, and mint a unique 
stamp for me with a value greater than n, you will be granted the 
privilege of bypassing my spam filter and getting a green light to my 
inbox. if you don't, then my spam filter will decide which pile to toss 
you into.

like all good things, it will have to reach some critical mass, and then 
everyone will see that it is, ultimately, in their best interest to use 
it. they can bitch and moan, kick and scream and complain the whole way, 
but just like upgrading from typewriters to word processors, from carbon 
paper to photocopiers, from telegraph to telephone... they will have to 
come along or be left on the side of the technological highway.

i will concede on one point: if/when hashcash is being used in 100% of 
mail systems, then spammers will have to accept that fact, and they too 
will have to adapt or become extinct. extinction is fine with me, but many 
will adapt, and accept that they must operate with a new restriction. 
if/when this happens, then the arms race of stamp size will begin... i'm 
not sure what that will lead to....


         ...atom

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