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LOAF - Distributed Social Networking Over Email
FamousLongAgo writes "LOAF (List Of All Friends) is an extension to email that lets you send out address book data without compromising your privacy. LOAF appends a hash-like data structure to each outgoing email, and collects similar attachments from the people who write to you. These files can be queried to see if they contain a given email address, but they can't be reverse-engineered to reveal the list of addresses used to construct them. LOAF lets you check whether someone emailing you for the first time is a complete stranger, or appears in the address books of some of your trusted correspondents. And as a decentralized application, LOAF offers an interesting alternative to current social networking sites like Orkut or Friendster."
Ok, I've had it with Friendster, Tribe, and all this social networking crap. Go to a bar, go to a park, hell go to a freaking CHURCH or something but if you want to make friends then for the love of Augusta Jane Chapin STEP AWAY FROM THE BLOODY COMPUTER. People are better grokked in person, and this virtual hooey is way overrated and ultimately unsatisfactory. If you're fat and ugly, go hang out with other fat and ugly people. Whatever you are comfortable with. But you just can NOT get the same social dynamics online as you do in the real world.
Why do you think people are such assholes online? You know, like me. Because the social dynamics are different and don't match reality. People don't have to be polite online, and you don't get to practice communications skills that make you successful in the real world.
And since the eventual goal is to get laid the physical verbal interactions are kind of important.
Having said that, this seems like an interesting technology, and doesn't seem as inherently annoying as Friendster. When the FAQ has stuff like this in it:
The false positive rate for Bloom filters is determined by the number of hashing functions, the size of the filter, and the number of entries in the filter, given by the approximate formula:
( 1 - e^(kn/m) )^k
It makes me go all warm and fuzzy.These files can be queried to see if they contain a given email address, but they can't be reverse-engineered to reveal the list of addresses used to construct them.
Or so they thought, untill they heard about the sha vulnerability.
I've refreshed the /. page a few times and still see no comments. How strange.
Anyway, how would something like this hold up in a spam blocking function? How easy would it be to get onto the LOAF list? And if the contents can't be listed, how are you to know that it's not chalk full of the bad stuff? How do you know that you aren't emailing to people whom you don't wish to receive your mails?
No sig for you. YOU GET NO SIG!
Could this be used in a spam filter? A somewhat adaptive whitelist?
Not that it would solve anything, but it could be useful...
'Sensible' is a curse word.
anyone else think linux on a floppy when they saw this?
You don't need to reverse it if you can brute force it.
Try not. Do or do not, there is no try.
-- Dr. Spock, stardate 2822-3.
(http://www.mail-archive.com/cryptography%40metzdo wd.com/msg02554.html
I'll believe it can't be hacked when its been in wide spread use for several years, and has been the subject of crypto seminars. Until then, I'm going to assume the spammers will break it.
Send this email to your LOAF within 3 minutes or suffer a tragic loss next week!
If you think
All you need to do is join a few mailing lists with people on it that use this. Then, you run you CD of email address through it, looking for hits. This gives you a much smaller list, but they're all confirmed, known good addresses. The cool thing, from the spammer's perspective is that you don't have to go out and harvest, people go out of their way to give you their friend's email addresses.
Good, inexpensive web hosting
It doesn't seem like it'd be hard to have a worm write an arbitrary address into your address book.
Then LOAF would propogate that address to your friends, and then spammers could use the address programmed into the worm as the from address.
On the whole though this seems like a really nice addition to existing spam blocking systems.
Unfortunately the cases where i recieve email from a friend of a friend are relatively rare - but that's just me.
It also does have some privacy issues - since it'd essentially enable me to check if one of my friends happens to have my wife in his address book...
LOAF lets you check whether someone emailing you for the first time is a complete stranger, or appears in the address books of some of your trusted correspondents.
What's the difference? Some of my most trusted confidants have systems riddled with spyware and viri. They're great people but Horrible users. I rarely give out my real email address for that very reason.
Michalangelo Progr
LOAF sounds wonderful until someone creates a LOAF-exploiting virus. If a friend becomes infected, their 0wned machine can send virus messages (with the friend's LOAF signature) that have a very high chance of being read and thus spreading through a LOAF network.
The challenge with any computer-based social network is not the "do I trust my friend" question but the issue of "do I trust my friend's computer that is sending me this message"? Perhaps all computers need a tamperproof hash that encodes their OS patch/AV update/spyware/firewall defense state. That way the message recipient can assess the trustworthyness of the sending machine.
Two wrongs don't make a right, but three lefts do.
Now you want to tell people to "Go ahead and open all those emails with attachments" ?
If they're doing it the right way, it can't be. For example, you could assign every address a random but calculatable value (for the hell of it, lets use the value of the product of all the ascii characters in their name). Thats a pretty random variable. You can check if an address matches it by caluclating its value and comparring, but you cannot reverse the process (due ot multiple possible matches). The cost you pay is that false positives are possible. In the above example, with 32 bit values, you have a 2^-32 chance of a false positive.
I still have more fans than freaks. WTF is wrong with you people?
For a minute there, I thought this was an actual readable article about a distro that was once fairly useful L.O.A.F. and its revival.
Guess not.
Being online give you freedom. Manners, grammar and spelling aren't eliminated, they become a choice. And as a choice, they can become something to be proud of.
Interacting with other people online has allowed me to get to know people from other countries and cultures, instead of being limited to a west Michigan culture where it's sometimes hard to find other people interested in the same things I am.
Finally, things like email and online forums allow me to communicate and cooperate with people in other time zones. I don't have to be awake for my message to reach my buddy in Mexico. Or my friends in Africa, Europe or Asia.
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You generally reverse engineer it because there is fundamental information loss in the hashing process. However, there are caveats.
For example, lets consider a really primitive hashing function: we add up the ascii values of all the letters in the the email address and that is the hash value. However, foo@bar.com and bar@foo.com obviously have the same hash in this case, so knowing that the sum is 1234, you can't determine which the address is.
Now if the hash is long and very good at avoiding collisions, you may actually be in more trouble than when using a weak hash, because the very rarity of hash collisions reduces the information loss (maybe there's only one string that includes an @ sign and is shorter than 40 characters that hashes to that value!) So, if we have some way of generating a string, fitting a specific template, that evaluates to a particular hash (and so far, the found SHA-0 collision is nothing of this sort), we can just generate all short strings that match that hash and look for one that could be an email address. However, a weaker hash would result in many plausible email addersses hashing to the value, which would increase false positives, but reduce the risk of finding the original addresses.
DVD encryption was reverse engineered because all the information was preserved. As long as the hashing function looses enough information, there is no way to recover the original email.
What you call "superiority" others would call "limiting". All of your "advantages" involve speaking to a small group of known people anywhere/anytime. In the physical world, you meet new people. New people bring new ideas, perspectives, activities, etc.
G
An (bad) example would be that the "encoding" function is the ascii values for the first and third character before the @ and the first character after the @ - those bits of a 128 bit Bloom filter are "lit up" for your address, so that means:
all map to the same bits being lit up in the bloom filter, there is no real way to "reverse engineer" it and since it does not assume no collisions (unlike MD5 and SHA*) it is not expected to have unique mappings - that's a feature, as they say.
you don't have any friends?
There are no atheists when recovering from tape backup.
If they release a worm, we'll finally know which ones of our friends were dumb enough to open attatchments :p
You don't need to extract every email in it to break it...
For example, if your employer got their hands on your list, they could check if you've been in contact with people at your competitors.
It's even worse if they try and get a false positive!
While IM was never mentioned in the article, my fear is that something like this is more likely aimed at IM users than others; quite an oximoron for an application designed to promote privacy and security. Also, since it seems to be based on a friend-of-friend approach, it would have to support the address book format of every friend that I excahange e-mail with, would it not? This all seems to be ignored in the article.
I'm an American. I love this country and the freedoms that we used to have.
Too bad I don't use electronic address books.
Yeah, back in my day we didn't have fancy electronic address books.
We only had paper address books. If I ran into a stranger, I would take my address book and smear it across his face one page at a time. If the ink rubbed off, then I knew they were a friend of one of my friends, and I could trust 'em.
And then we could drink beer together. But we didn't have carbonation back then so we used straws to blow bubbles. There wasn't any plastic back then neither, so we had to find a swamp and cut some reeds...
"Can of worms? The can is open... the worms are everywhere."
A ``me too'' attack consists of taking someone else's filter and claiming it as your own. This does not help you get recognized by other correspondents - that determination is made by comparing your email address against their list of stored filters - but once you are 'in', it will make you appear to share many contacts with people you actually don't know well at all.
Why not just salt the SHA1 function with the filter owners email address? That way somebody could never take my filter and claim it as their own, since the bloom filter won't match anything when the hash values are produced with their email address as the salt.
Am I missing something?
Gee...hasn't anyone else noticed what else we get with LOAF? Longer shit on emails!
Unless the application (which it might, I haven't checked) filters the LOAF signature, we'll have a nice influx of three-word emails with 25 lines of crap at the end of each, plus headers, plus the 50-line signature that I flamed you about last week, plus your cutsey signoff, plus the last 14 messages you've quoted in the discussion thread because you were too fucking lazy to edit them off, plus a poorly-rendered ASCII-art picture of Britney Spears showing her hot grits, plus...
Well. You get the picture. I can't wait until I can be on mailing lists that have 95 LOAF signatures at the end of each email because they were running Outlook and it couldn't filter them out.
Any way to stick those babies in a header? At least they can be hidden, then. The bandwidth is just a victim anyway.
Blog,Twitter
Perhaps limit it to a couple of steps away.
I'm not sure if anyone else has posted this idea yet, 'cause I'm way too lazy and tired to read the whole discussion, so I'm just throwing this out there....
It seems kind of sad and pathetic that we need something that "checks incoming mail against the address books of your friends" in an effort to get rid of email from complete strangers....
The internet was supposed to, among a thousand other things that are now long forgotten, get strangers together who shared common bonds of interest or study. Hobbies, ideas, whatever...
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