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13,000 Passwords, Usernames Leaked For Major Commerce, Porn Sites

Fweeky Re:Didn't say it's stupider than stupid. (149 comments)

It's not being used as a key. Key stretching would be pointless. You stretch to get a longer key if your goal is to derive a strong key

You want a strong key! Key stretching isn't just about making a physically longer key, it's about making a stronger one, such as by iterating your hash function a million times.

KDFs are for key derivation. That's why they're called key derivation functions. How is that hard to understand.

This is not in question. What is in question is why it's not exactly what you'd want out of a password hashing function - what difference does it make whether you're going to pass it to AES or to a comparison function?

about three weeks ago
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13,000 Passwords, Usernames Leaked For Major Commerce, Porn Sites

Fweeky Re:Didn't say it's stupider than stupid. (149 comments)

A better choice is a properly vetted hash that's designed as a hash, such as SHA256

... which you then need to, at a minimum, apply salting and key stretching to. Good work, you just rewrote most of PBKDF2, just without the peer review, sane defaults, and for most people, probably in a language where the function call overhead exceeds the cost of the hashing.

Using a KDF as a hash is like using a butter knife as a screwdriver - it gets the job done, and professionals normally use the tool designed for the job rather than substituting.

Hashes are not designed for password storage, that's the entire reason we're having this conversation in the first place. People use KDF's for password storage because that's what they're made for. Anyone who uses a plain old hash has to make a KDF out of it. How are they different?

about a month ago
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13,000 Passwords, Usernames Leaked For Major Commerce, Porn Sites

Fweeky Re:no, no, and no (149 comments)

Yes, I used "computationally complex" to mean "takes a lot of steps to complete". You and your "words mean stuff", stop evading the point.

Why is a KDF like PBKDF2, bcrypt or scrypt, a poorer option for password storage than rolling your own? Please use words which mean stuff.

about a month ago
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13,000 Passwords, Usernames Leaked For Major Commerce, Porn Sites

Fweeky Re:no, no, and no (149 comments)

You want the hash algorithm to be SLOW, not "well optimized" ... You don't want it to be computationally complex.

How do you make an algorithm that's slow without being computationally complex? Writing it all in PHP doesn't count.

The algorithm has to be slow because it's a lot of work. Your implementation has to be fast to maximise the security benefit of using it in the first place.

You don't care about turning it into an unpredictable number.

What else do I want a hash function to return?

In fact you sometimes enforce O(1) time, you don't want a longer or different password to take longer to hash, because that facilitates timing attacks.

Pad your inputs and use constant time comparison functions, kids.

about a month ago
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13,000 Passwords, Usernames Leaked For Major Commerce, Porn Sites

Fweeky Re:those are key derivation, not for passwords, co (149 comments)

Er, not really? You want a well-optimized function to turn a password into a very big unpredictable number in a way that's computationally complex, and that's precisely what KDFs are made to do. The entire crux of your argument against such use seems to boil down to "but they sometimes let you specify how big a number you want", as if this added complexity and risk somehow massively outweighed that created by rolling your own slow crappy little alternative.

about a month ago
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Backblaze's 6 TB Hard Drive Face-Off

Fweeky Re:Meaningless? (173 comments)

I find it odd that the WD drives, at the 5400rpm speed, were able to write data faster than the 7200rpm Seagate drives.

Maybe the Seagates are more sensitive to vibration, either from making more of it when you shove 45 into a cheap metal box, or by being less tolerant to it because they're pushed harder.

about a month ago
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Seagate Bulks Up With New 8 Terabyte 'Archive' Hard Drive

Fweeky Re:Just in time. (219 comments)

I recall reading that the uncorrectable read error rate tends towards the 2TB mark.

12.5TB, assuming the specified 1-in 10^14 bit uncorrectable-read-error rate specified for most consumer drives is accurate. I certainly don't see rates anywhere near that high with my consumer drives, but I could just be lucky.

about a month and a half ago
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Windows 10 To Feature Native Support For MKV and FLAC

Fweeky Re:Rather late (313 comments)

I still have two or three recent (i.e. last four or five years) devices that have problems seeking VBR files or displaying the proper duration.

Even foobar2000 has issues with seeking in MP3s. From the FAQ:

Why is seeking so slow while playing MP3 files?

The MP3 format doesn't natively support sample-accurate seeking, and sample accurate seeking is absolutely required by some features of foobar2000 (such as .CUE playback). MP3 seeking can't be optimized neither for CBR files (frame sizes aren't really constant because of padding used), nor for VBR files (both Xing and VBRI headers in those files contain only approximated info and are useless for sample-exact seeking). Therefore MP3 seeking works by bruteforce-walking the MPEG stream chain and is appropriately slow (this gets faster when you pass through the same point of file for the second time because seektables have been built in the RAM).

about 2 months ago
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Windows 10 To Feature Native Support For MKV and FLAC

Fweeky Re:Where does this leave independant media players (313 comments)

You need weird-ass buggy fb2k plugins, but are only missing format support in WMP? Do you play a lot of ancient tracker music or something?

If you find the fb2k interface so intimidating perhaps you'd be better off with its much simpler cousin, Boom. Not sure if it's got much support for particularly oddball media formats though.

about 2 months ago
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Multi-Process Comes To Firefox Nightly, 64-bit Firefox For Windows 'Soon'

Fweeky Re:Tempting (181 comments)

Multi-process architecture... I've not really noticed a problem with the threaded one, and Firefox already sticks flash objects in a separate process. So what's the real draw

Isolation. The same reason you want different apps to have their own processes instead of having the whole of userspace in one big blob. You can give processes reduced privileges to reduce the scope of exploits, hangs and crashes don't take down more than they have to, and leaks don't force you to restart the entire system to recover resources.

Plus it makes for simpler concurrency. Kind of handy when you've got a stop-the-world garbage collector if you can just split the world into many smaller independent units, each able to run at the same time and each with an order of magnitude less work to do and no synchronisation to worry about.

64bit... again, bragging points about how many bits you use, no functional difference to anyone

ASLR is a fuckload more effective when it has a reasonably sized address space to work with, and 2^32 is miles away from being reasonable. It's the difference between an attacker having to guess one of 8 locations and one of 8 billion. Plus, memory mapping things is awesome, and also a fuckload easier with a reasonably sized address space.

And hey, some of us actually use our browsers quite a lot. Mine's eating 5.5G right now. So many windows and tabs, and absolutely no fucking reason whatsoever why that should be considered even slightly unreasonable.

about 2 months ago
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Passwords: Too Much and Not Enough

Fweeky Re:Per-user salting (223 comments)

How many people do per-user salting of the password hash?

People spouting things like this is precisely why we have tens of millions of web apps using shitty password storage solutions that boil down to HASH(salt + password) and are thus borderline fucking useless. It's like asking if someone's home-grown encryption algorithm uses an IV - that might be an important part of it but it's kind of missing the point.

If you're using passwords for authentication in your app, use a recognised key derivation function. Use PBKDF2 or bcrypt and tune them to take at least 100ms to run. If you're extra paranoid, use scrypt and tune it to take 100ms and 16MB of memory. If you're doing anything else without having a well-received peer reviewed academic paper describing it, you might want to reconsider.

about 3 months ago
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Choose Your Side On the Linux Divide

Fweeky Re:My opinion on the matter. (826 comments)

FreeBSD uses init.d

FreeBSD uses rcNG, acquired from NetBSD (basically shell scripts and a binary for resolving dependency order defined in magic comments), on top of a simple BSD-style init. There's some vague movement towards porting launchd, but I don't think anyone's holding their breath.

about 5 months ago
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Facebook Seeks Devs To Make Linux Network Stack As Good As FreeBSD's

Fweeky Re:This does pose the question: (195 comments)

pkgng's made port upgrading much less burdensome - even fairly complex dependency changes can be handled automatically as of 1.3, and the official package repositories are a lot more useful now. They even have stable security-fix-only branches.

I still make my own customised builds, but I make binary packages in an isolated jail using poudriere. 99% of upgrades are a matter of updating its ports tree, running rebuild-packages, and running pkg upgrade on all my machines.

You couldn't pay me to go back to portupgrade/portmaster/portmanager.

about 6 months ago
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How long ago did you last assemble a computer?

Fweeky Re:so, I'm in the more than 8 yrs ago camp (391 comments)

If you're actually that bothered about the data integrity benefits of ZFS, it'd probably have been a good idea to go for ECC memory. Pools can pretty much self-destruct in face of memory corruption, and memory failure rates are not that much different to disk failure rates.

Such bullshit that it's so rare and poorly supported. The actual material cost is tiny - a few more motherboard traces and 1 extra memory chip for every 8. With AMD at least it's mostly a case of finding a good motherboard vendor, instead of the server/workstation board and CPU combo Intel demand.

about 6 months ago
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FreeBSD 9.3 Released

Fweeky Re:What is BSD good for? (77 comments)

Not really - ports doesn't even have a *concept* of upgrading, it's just uninstall/reinstall and hope you can work out how to handle all the dependencies. This is why FreeBSD's got so many tools for managing them - portupgrade, portmanager, portmaster, all with their own little and not so little quirks.

We do have an apt-alike these days, in the form of pkgng. pkgsrc also has pkgin.

about 6 months ago
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FreeBSD 9.3 Released

Fweeky Re:What is BSD good for? (77 comments)

It's stable enough for general use, but maturity counts for a lot with filesystems, especially when they're as complex as ZFS. It's also a third-party add-on rather than an official part of the OS which does raise some issues.

Conversely it's practically the default on FreeBSD, and it's been available since 2008.

about 6 months ago
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Ask Slashdot: Practical Alternatives To Systemd?

Fweeky Re:Accept, don't fight, systemd (533 comments)

Every release seems to take the system one step closer to exactly what you describe

Erm, like what?

about 9 months ago
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Ask Slashdot: Practical Alternatives To Systemd?

Fweeky Re:I've been toying with rolling my own distro (533 comments)

pkgng's still missing the ability to track certain changes automatically, so you occasionally have to force-remove a package or manually change an origin as per /usr/ports/UPDATING. I think they're expecting to resolve that in 1.3 fairly soon.

I've been using it for about 18 months across a small group of machines with about 1400 packages between them, and it's pretty much entirely demolished any apt-envy I've had.

about 9 months ago
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OpenSSL Cleanup: Hundreds of Commits In a Week

Fweeky Alternatively (379 comments)

You can also track the changes in a somewhat friendlier format using FreshBSD. Full commit messages (up to a point) upfront, more useful Atom feed, breakdown by committer etc.

about 9 months ago
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How Data Storage Has Grown In the Past 60 Years

Fweeky Re:How long id a song (100 comments)

Reality disagrees with you. The user data portion of a sector is normally a power of two for convenience, being used on computers with power of two page sizes, but drives themselves are no more limited to power of two number of or size of sectors than your computer is limited to power of two size array or structure lengths, and this is readily confirmed by the existence of disks with 520 byte sectors (and somewhat different physical sizes) and an irritatingly diverse range of sector counts.

about 10 months ago

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