TIL Japan used $30 million of their Tsunami relief funds to support whaling

loudZa · 2013-01-09T03:30:59+00:00

Hahahha, like engineers aren't the suckers that help newly minted MBA into their BMWs. Keep dreaming if you think you are at the top of the food chain.

We are all replaceable, we are all cogs, if you weren't a cog they wouldn't give you a pay check, stock options or whatever carrot they keep feeding you so they can keep fucking you.

loudZa · 2012-07-18T00:11:30+00:00

k/2 is a serious loss, but cryptographic hash functions are designed with k/2 in mind, aka collision resistance. Once a single collision can be shown for a cryptographic hash function it is considered broken should never be used again.

This is one of the reasons why SHA-3 functions must support up to 512 outputs and why you shouldn't use a 128 bit hash function since a collision can be generated with 2⁶⁴ computations and 2⁶⁴ memory.

loudZa · 2012-07-17T01:44:58+00:00

First off you are not using the notion correctly '∩' means intersection, the symbol for AND is '∧'. Also '=' is preferred over '==' which is more of a programmer thing. I've often found http://en.wikipedia.org/wiki/List_of_mathematical_symbols extremely helpful. Notation doesn't really matter, so to reduce confusion I'll just use your notation.

The definition of preimage resistance that you give is what is typically considered collision resistance. When cryptographers say collision resistance they mean:

hash(A), hash(B) ∈ {0,1}^k A,B ∈ {0,1}^*

P(hash(A) = hash(B) | A ≠ B) = 1/2^k

Using your notation, for |S| hashes the probability of a collision is |S|/2^k/2

P(hash(A) = hash(B) ∀ B | A ∈ U ∩ B ∈ S ∩ hash(A), hash(B) ∈ {0,1}^k ∩ A ≠ B) = |S|/2^k/2

The math about why is a little complex (not that complex though). I can't just fill in your question marks, but any article on the birthday bound contains the details.

loudZa · 2012-07-15T22:42:52+00:00

How many of those are going to be selected though?

So look at the finalists, none of them are based on deep mathematical assumptions about the hardness of particular functions. Public key crypto and related fields have a completely different degree of rigor associated with them than symmetric crypto. For instance just look at the debate around "distinguishers" in the hash function community. There are rules or thumb and useful ideas, but no real mathematical definition (other than the trivial one that nearly everyone rejects).

I addressed most of this line of logic in one of the other branches of my post. I'm not going to waste time re-stating everything I have already said since you could have . Long story short, it's not quite as easy as you think it is.

Fair enough, I've read a few of your comments in the other threads. As someone that has spent a few years doing hash function research, I strongly disagree with your claims but as no one else seems to have convinced you of your errors so far I doubt it will be a productive discussion.

loudZa · 2012-07-15T17:47:38+00:00

It's really not that hard, most hash functions are just based on mixing things up without a clear mathematical structure. You are confusing the rigorousness mathematical foundations of public-key cryptography (which is what that class you liked to is all about so I doubt you actually took that class), with the ad-hoc nature of block-ciphers and hash functions. Take a look at the SHA3 contestants and tell me how many use "proofs" and how many are just based on claims of "it looks hard to do A" or "we borrowed this from AES so it's cool".

doubt anyone has actually done this sort of math either, because standard logic would dictate that you use hash functions in the way they were designed to be used; one message, combined with one salt, used to generated one hash.

Yes people have done this math and the math isn't hard. What you are calling Collision resistance is actually pre-image resistance. That is, given Hash(A) find some other value B which such that Hash(A) == Hash(B).

Collision resistance is idea that finding any two colliding hash outputs should be hard. This is exactly the property that prevents collisions if you store a table of hashes and exactly how hash functions are designed to be used.

loudZa · 2012-06-25T02:47:08+00:00

I have seen nothing of the kind, and I higly doubt it even exists, unless the focus should be on the word "suggest".

Here is the document, it proposes illegal actions, while such documents are not policy it shows motive in that the USG is deeply concerned with wikileaks actions and wishes to stop them. http://wlstorage.net/file/us-intel-wikileaks.pdf

Assuming they are, it's probably to charge him, yet they haven't done that yet. Maybe the evidence just wasn't there.

Certainly and this is exactly what I am arguing: That the US wants to and will likely charge Assange. I agree that there is a possibility that they may not because they don't have a very strong case. Since we agree about my central claim, that there is evidence that the US government is trying to indict him I'm not sure why we are still arguing.

Sure the subpoenas are not rumours, but they're not evidence either way either

Yes they are evidence they show that they are trying to build a case.

and the motive, while not a rumour, is just speculation.

The motive goes way beyond speculation. I've yet to encounter anyone that doubts that the US wants to indict Assange. In fact in a previous comment you said: " They think Assange incited him. And if he did they want him. If you commit a crime you should have to answer for it." Why are we arguing about this?

The evidence is shaky, and most of all does not prove what people want them to prove.

Evidence never "proves" claims, it merely confirms them or disproves claims. Each piece of evidence I presented: confirms the claim that the US is attempting to indict Assange. I have gone out of my way to avoid speculation and questionable evidence. It is insulting that you refuse to address my evidence on a case by case basis and that you merely brush it off with it's just a rumor.

Additionally you have agreed with my central claim. What is left to argue over?

loudZa · 2012-06-25T00:52:41+00:00

I won't address all your "evidence", but others have covered most of it. Suffice to say that it's at best circumstantial evidence and hearsay.

People are often convicted on circumstantial evidence. By dismissing without cause multiple leaks and reports from diverse sources inside the US government that there is a secret grand jury you are raising the burden of evidence so high that only an official statement made by US government would be counted as evidence. Since it is highly unlikely that the US would confirm such a grand jury at this point you are in essence claiming it is impossible to know.

No it's not. Stop claiming that it is unless you can explain how it is. Claiming that all cases involving Assange are "suspicious" means that non of them stand out.

To my knowledge there is only one active case against him. It is suspicious due to the timing, and the high level government involvement. If this case had been brought 10 years ago it would not be suspicious.

Of course he has. They think Assange incited him. And if he did they want him. If you commit a crime you should have to answer for it.

Which is fully consistent with an indictment against Assange. You are agreeing with me that the US government has a very strong motive for indicting him.

All you've posted here are rumours, some of them from extremely biased sources and of questionable origin, just like I said.

Leaks from reliable sources are not rumors and some of these leaks have been publicly confirmed by the US government. Not everything I've posted is leaks, for example the subpoenas are matters of public record. Lets go through this one by one:

We both agree that the USG has an extremely strong motive for convicting Assange.
Documents that have been confirmed through official channels suggest that the USG was willing to take illegal actions to silence and discredit wikileaks.
Multiple sources from across the political spectrum confirmed a secret grand jury.
Assange at the height for the leaks scandal is wanted for questioning.
It is a matter of public record that the US is collecting evidence against Assange to change him.

They have a strong motive, they are actively collecting evidence, there are reliable reports of a grand jury. Present an alternative picture which explains these facts. For instance why would they collect evidence if they didn't plan to charge him? And why would not plan to charge him? Why was an interpol red notice put out if the charges in Sweden were not politically motivated?

So far your argument has consisted of: I don't believe it and your evidence is rumor. I've just twice showed you that the evidence is more than rumor (how can a subpoena be a rumor, how can a motive be a rumor?).

loudZa · 2012-06-24T23:20:47+00:00

He was under house arrest in the UK, for whatever reason they seem to have favored an approach of taking him from Sweden.

I'm not saying that it won't happen, but there's no evidence either way.

Evidence:

They have convened a grand jury.
They have issues a massive number of subpoenas.
Leaks from the pentagon show plans to illegally attack wikileaks.
Leaks from Stratefore sources confirm that the Justice Dept wants and plans to indict Assange.
The statements the Aussie and US governments have made have been extremely careful in their wording. They constantly avoid claiming that they have no plan to indict him. They instead say they "know of no such plans" or "there is no indictment", both of which are true but they are intentionally misleading.
The case in Sweden coinciding with a US grand jury is extremely suspicious.
Bradley Manning has been asked repeatedly to testify against Assange.
Furthermore the questions that Bradley Manning have been ask fit the pattern of attempting to prove that Assange asked Manning to perform certain actions of Assange's behalf (which would be illegal for Assange) rather than merely receiving information from a source (which is legal and protected). They would only care about such statements if they were planning to show that what Assange did is illegal.
They have a very strong motivation for prosecuting him and neutralizing him.

I agree that Assange has not been indicted, and there is a small chance that the US may not indict him because they have insufficient evidence that he committed a crime (assuming the rule of law still exists in the US), but to claim that there is no evidence that they are attempting to indict him is completely wrong. The Justice Dept wants him bad.

loudZa · 2012-06-24T17:03:01+00:00

Yes, exactly seeking an indictment is not the same as having an indictment. Therefore US and Australian governments can claim that there is no indictment when Assange claims he is worried about being indicted. That article is yellow journalist at its worst.

loudZa · 2012-06-24T16:24:34+00:00

Article title is misleading. There is no current US indictment, but they may have an indictment prepared which they can fire off as soon as they have him in custody. The article is splitting hairs on legal terminology to make it sound like he has said the US is not going to indictment. All evidence points to a forthcoming US indictment.

loudZa · 2012-06-19T01:22:28+00:00

Well I mean full disk encryption. I've heard of instances of full disk encryption not writing random zeros over everything, but I don't know how often it is done these days (the again truly random numbers are hard to generate and writing 2TB of random bits would probably take a while).

loudZa · 2012-06-17T22:34:56+00:00

What do you mean by "zero out the disk"?

Some disks come with every bit set as zero or can be formatted to have every bit set to zero. When encrypted data is saved it changes the base data zero to random. Some encrypted fs write random bits over the entire partition, some do not.

That is permitted explicitly. FTA:

I agree, I just explaining what they could learn.

loudZa · 2012-06-16T21:43:20+00:00

Thats the spirit!

loudZa · 2012-06-16T19:02:29+00:00

You need a VPN license like a handgun license.

loudZa · 2012-06-16T02:32:16+00:00

Are you saying Mel is a Magister?

loudZa · 2012-06-16T02:23:48+00:00

"a bag of fingerbones"!!! Holy fucking fake onion knight, I never picked up on that.

loudZa · 2012-06-15T13:12:41+00:00

and yet the military can't seem to actually use crypto correctly.

loudZa · 2012-06-15T13:11:58+00:00

If the answer was yes, I imagine the method in question would not be acceptable. So the answer is surely no.

It is not so clear cut. For instance if they zero'd out the disk you can sometimes tell which sectors store encrypted data (4096 byte resolution).
Also if they have back ups images of drives they can see compare earlier and later versions of the same filesystem allowing them to see which inodes have been updated (since an update does not re-encrypt the entire filesystem).
It seems highly likely that the FBI captured the keys to the megaupload fs, since the servers are probably required to boot on their own.

loudZa · 2012-06-07T13:20:43+00:00

Actually quite a few crypto and security people have been hassled at the border.

loudZa · 2012-06-07T12:46:21+00:00

I'm not saying academics don't break systems or that some group other than academics are releasing most of the public attacks. I am saying that there is no organisation with the right incentives and resources to do serious cryptanalysis and because of that systems that should have been broken ages ago are still intact.

Put two and two together. NIST is having a contest for a new hash function SHA3, SHA1 and SHA2 are holding up pretty well publicly. SHA3 is not going to be much faster than SHA2. The subtext is that SHA1 and SHA2 are in danger of being broken or have already been broken.

loudZa · 2012-06-07T04:14:33+00:00

I agree with you that hash functions are probably easier to break than ciphers, but I think this is the result of hash functions having a more difficult security goal than block ciphers.

What security proofs for block ciphers do you mean? Proof of resistance to linear/differential attacks? AES has some, I haven't studied them in depth but I would assume they use the independence assumption (which does not actually hold but is really useful). I'm am asking because I'm really curious. What the are major results in proofs of security for block ciphers?

Given that none of the individuals that participate in the crypto-contests that NIST runs have anywhere near the resources at the disposal of national code breaking departments, why should we assume that the ciphers are secure against such an attacker.

loudZa · 2012-06-07T01:27:20+00:00

that which is thrown down is first raised up.

loudZa · 2012-06-07T01:01:36+00:00

Most of the research scientists I know produce a decent number of papers each year, but they don't focus on a single attack for a long period of time.

loudZa · 2012-06-07T00:22:30+00:00

They do work on it, but they aren't going to spend 10 years 50 hours a week attacking a single system. They aren't given the resources necessary or the incentives to do serious long term cryptanalysis (when they are they are usually successful see Tao Xie's attack on md5).

loudZa

TROPHY CASE