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Submission + - HardenedBSD Completes Strong ASLR Implementation->

HardenedBSD writes: A relatively new fork of FreeBSD, HardenedBSD, completed their Address Space Layout Randomization (ASLR) feature. Without ASLR, applications are loaded into memory in a deterministic manner. An attacker who knows where a vulnerability lies in memory can reliably exploit that vulnerability to manipulate the application to doing the attacker's bidding. ASLR removes the determinism, making it so that an attacker knows that a vulnerability exists, but doesn't know where that vulnerability lies in memory. HardenedBSD's particular implementation of ASLR is the strongest form ever implemented in any of the BSDs.

With HardenedBSD having completed their ASLR implementation, the next step is to update documentation and submit update the patches they have already submitted upstream to FreeBSD. ASLR is the first step in a long list of exploit mitigation technologies HardenedBSD plans to implement. HardenedBSD has also implemented other exploit mitigation, security, and general hardening features, providing great security for FreeBSD.

Link to Original Source

Comment Re:File versioning and backup flags (Score 1) 484 484

DragonFlyBSD's HAMMERFS does much of this - you can examine the version history of files and directories using hammer history and undo commands, and reference versions directly by appending @@ to filenames.

You can control how long history is preserved for and in what level of detail, as well as efficiently replicate it all across the network to remote filesystems (which can have their own, different rules). All this in addition to the more traditional named snapshots approach you're limited to with, e.g. ZFS.

https://www.dragonflybsd.org/d...

Comment Re:SpiderOak (Score 1) 107 107

Their mobile client is open source: https://github.com/SpiderOak/S...

The desktop client is mostly unobfuscated Python bytecode and easily inspected, docstrings, symbol names and all, with a bytecode decompiler. Not good enough, but at least a bit more transparent than most.

Comment "Best"? (Score 1) 558 558

Guess that has to be my main server, even though it's a few generations older than my desktop, it has more cores, more IO, more memory and more storage. It runs FreeBSD.

Case: SuperChassis 745TQ-R800B (pic)

Motherboard: Supermicro X8DTN+

CPUs: 2 x 6-core Xeon L5639 @ 2.13GHz

RAM: 144GB - 9 x 16GB DDR3-1333 ECC Reg

Primary Storage: 2 x SanDisk Extreme Pro 960GB, ZFS mirror.

Mass Storage: 6 x 5TB Toshiba MD04ACA5, ZFS 3 x mirror.

Disk controller: IBM M1015, seems one of the most favoured HBA's these days.

Keyboard: NTC KB-6153EA with clicky White Alps.

I play with search engines and stuff, the memory comes in handy and I got it for a great price.

Desktop is a 32GB ECC quad core Haswell Xeon mumble mumble running Windows 8.1, with a pair of 30" 1600p monitors and a 20" 1600x1200. Nice having space to put stuff. Also nice having memory that doesn't silently corrupt itself every few months, you crazy kids and your non-parity.

Comment CVE-2015-3298 (Score 1) 88 88

In case anyone missed it, if you're using one for OpenPGP key use you might be vulnerable to a pin bypass attack. Details on how to check are on that page.

If you have a vulnerable device, YubiCo will send you a free replacement upon request - just open a ticket with your serial and order numbers.

Comment Re:Didn't say it's stupider than stupid. (Score 1) 149 149

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?

Comment Re:Didn't say it's stupider than stupid. (Score 1) 149 149

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?

Comment Re:no, no, and no (Score 1) 149 149

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.

Comment Re:no, no, and no (Score 1) 149 149

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.

Comment Re:those are key derivation, not for passwords, co (Score 1) 149 149

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.

Comment Re:Meaningless? (Score 1) 173 173

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.

Comment Re:Just in time. (Score 1) 219 219

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.

Comment Re:Rather late (Score 1) 313 313

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).

Comment Re:Where does this leave independant media players (Score 1) 313 313

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.

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