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Submission + - First victim of SHA-1 collisions: Subversion. Technique was reverse engineered

Artem Tashkinov writes: A WebKit developer who tried to upload "bad" PDF files generated from the first successful SHA-1 attack broke WebKit's SVN repository because Subversion uses SHA-1 hash to differentiate commits. The reason to upload the files was to create a test for checking cache poisoning in WebKit.

Another news story is that based on the theoretical incomplete description of the SHA-1 collision attack published by Google just two days ago, people have managed to recreate the attack in practice and now you can download a python script which can create a new PDF file with the same SHA-1 hashsum using your input PDF. The attack is also implemented as a website which can prepare two PDF files with different JPEG images which will result in the same hash sum.

Submission + - White House blocks news organizations from press briefing (

ClickOnThis writes: CNN reports that it, along with several other major news organizations, were blocked from attending a press briefing at the White House today. From the article:

The New York Times, the Los Angeles Times, Politico and BuzzFeed were also excluded from the meeting, which is known as a gaggle and is less formal than the televised Q-and-A session in the White House briefing room. The gaggle was held by White House press secretary Sean Spicer.

In a brief statement defending the move, administration spokeswoman Sarah Sanders said the White House "had the pool there so everyone would be represented and get an update from us today."

The pool usually includes a representative from one television network and one print outlet. In this case, four of the five major television networks — NBC, ABC, CBS and Fox News — were invited and attended the meeting, while only CNN was blocked.

And while The New York Times was kept out, conservative media organizations Breitbart News, The Washington Times and One America News Network were also allowed in.

Comment Re:So how is this any different than before? (Score 1) 209

I agree this almost seems to be a non-story. I read it as the FCC Chairperson announcing a possible way to curry favor with the FCC. I suppose time will tell if any non-mandating initiatives are introduced to encourage adoption.

that the free market isn't implementing a feature he thinks is necessary - sounds like a failure of the free market to me.

That would imply the market is supposed to have optimized in accordance with preferences of one man. Excepting possibly a post-scarcity society (replicators anyone?), the market cannot optimize everyone's preference. There are lots of things I would like the market to manifest but that I don't see them doesn't mean the market has failed.

Comment Re:Surprising (Score 1) 243

Umm... citation needed? I live in Iowa.

The infrastructure there is great.

Tell that to people from Wisconsin, it is recognized by both sides that theirs is better. We are better than we were thanks to a tax hike in 2015. I would not be one to call what we have bad, but it is not "great."

Tons and tons of barely used roads (and bridges, obviously).

Barely used? I suppose you could find ways to measure it to make that case, but no one here is thinking that way. If you look at the number of cars per unit time compared to some congested California corridor sure it would seem barely used but that is not really a fair comparison if you consider, say, population density. It might be worth mentioning that a lot of the lesser roads are limestone / gravel.

People in the least dense parts of the state even get fiber to their doors

I am reading this over an expensive (>$90/mo for 50 GB of daytime usage) satellite Internet connection because that is the only access available. It is so slow at the moment, that I cannot even load my account information to see what the exact cost it.

The most surprising thing about this story for me is that Iowa needs 5,000 bridges

In the 5 miles to get from my home to the post office, I cross 5 bridges. Really not sure how else to deal with all the running water that needs to be crossed.

Comment Re:BS detector went off and is overheating (Score 1) 309

I think there is a pretty clear distinction between standard functions you DON'T have to provide definitions for because they are standard, and arbitrary functions you made up on the spot, and had to define before using.

This is where we disagree. Someone had to define the functions (NB. many functions include constants in their definition). From what you have said, I can derive two possible definitions of "standard". The first being functions you expect people to know. This is not a reproducible definition because what you expect is not likely to be the same as what another individual expects. For example not everyone knows the inverse trig. functions. The second interpretation would be functions that are externally defined such that the definition can be looked up. To me, this does not provide any clear restrictions on the mathematical domain, opening up for all sorts of tricks:

naming f(x) was only for convenience, I could have written it as:
((lambdan . (n + pi)) 4+4-4-4) [lambda should be the lambda character, but /. does not seem to display it.]

Valid math. Everything is externally defined. Sure it is technically still an arbitrary function, but then I could also argue repeated application of a function you consider "standard" is also an arbitrary function. I do not see what grounds is there are for disallowing an entire mathematical system, but if you did, then I'd re-write it using currying notation. If you disallow that too, then I might try restating it using category theory. This continuing shows the distinction is arbitrary.

Comment Re:BS detector went off and is overheating (Score 1) 309

You seem to be confusing operators (or, more generally, functions) with constants here. arccos is just an operator, much like negation, addition, subtraction, etc. Pi is a constant, a numerical value, it has no other interpretation.

I think you overstate the distinction.

I guess you could also claim: 4+4-4-4+pi, claiming that that thing on the end is just a mathematical symbol and therefor a legitimate part of the equation

Let f(x) = x + pi (NB. we just curried addition) Therefore, 4+4-4-4+pi = f(4+4-4-4).
Indeed, that part at the end was just some mathematical function. In fact, lambda calculus could be used to show all all your constants are functions.

I am not saying that opening up the problem beyond arithmetic is consistent with the spirit of the question, just pointing out the once the metaphorical flood gates are open, the distinction between what is and isn't allowed is not simple.

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