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Comment IPv6 deployment (Score 1) 190

And I'm telling you :
- you DO NOT need to be on an unaddressable private address (192.x.y.z or fxxx:::) to not receive any traffic.

No shit. Then again, how many "average joe 6-pack" users get assigned anything bigger than a /32 (i.e. a single address) for IPv4, or anything at all for IPv6?

Here around on our side of the pond ?
Let me count :

- Most of the ISP here around in Europe that I know of (Switzerland, France, Germany) are providing IPv6.
Usually they are 6RD (rapid deployment), i.e.: their network (fiber, xDSL, etc.) is still legacy IPv4,
but their router automatically establish a 6to4 tunnel to the ISP's IPv6 access point,
Usually, most 6rd deployment offer /60 or /56 prefix, so each (IPv6-enabled) device on the home network can get its very own 64bits suffix based on the MAC-Address (and the router get a few extra 4 or 8 bits of headroom for its internal management).

So anyone plugging "the box" they've received from their ISP is automatically on IPv6.
And automatically getting sensible IPv6 packet filtering on said box (to go back to the subject of this discussion)
(And hopefully also getting sensible default passwords for amdin and Wifi in the form of long random base32 strings printed on the backside of the box)

- Lots of 3G/4G wireless providers are moving to IPv6 (well, obviously as 4G is a purely packet-switched network. IPv6 is more or less an unofficial requirement)

(Though usually, a smartphone will get a publicly addressable IPv4 and IPv6 on lots of networks. Not all though, some wireless providers are moving to NATed IPv4 and only publicly addressable for the IPv6 prefix)

(3G/4G to USB+Wifi routers do work similarily to above-mentionner xDSL/FITH routers. They advertise a publicly accessible IPv6 prefix and provide packet-filtering).

- Most universities I've seen also provide both IPv4 and IPv6 (but usually provide publicly addressable IPs on both).
(Though not necessarily on the "eduroam" shared wireless network. They used to be on IPv4 on some universities, and as of lately, all univesrities I've been in seem to move their eduroam on a different special IPv4-only subnet).
(And though to go back to the current discussion, universities here around seldom do any filtering. As soon as you plug in your laptop, your start to see failed login attempts in your SSHD logs)

- If you want your very own special IPv6 prefix, you can get one from SiXXS over a 6in4 or AYIAY tunnel.
(But then again that's not average joe).

And with only a single globally routable address, you do NEED to be on RFC1918 network.

Obviously this isn't the only way one can do NAT, but it's the only way joe sixpack's router does it.

Most users in a non backwater countries will get a 6rd publicly addressable IPv6 prefix, too.
By default, the box they've received from their ISP and they've plugged into the wall will filter the packets by default.

So please stop with this "NAT increases security".

And I'm telling you, the extra security provided to joe sixpack DOES come from the fact that he's being NATted, since he's still unreachable when any other packet filtering is disabled.

(emphasis mine)
Yup. We've reached a conclusion.
We both agree that for security, you need packet filtering.
You need a "magic box" standing between the wild wide interweb and the home network that does this filtering.
Usually this box is the xDSL/Cable/FITH/whatever router that the user has recieved from the ISP.
NAT'ing, is one of the peculiar types of packet filtering that happens on this box and provides some form of security (simply because of the reason it's a type of packet filtering).

IPv6 by itself isn't usually subject to NAT'ing (not needed, nearly every deployment I've encountered - include at home of random non-techie users - gets a publicly addressable prefix), but still isn't any less secure BECAUSE IT NEEDS TO GO THROUGH THE EXACT SAME MAGIC BOX (the router) THAT STILL DOES PACKET-FILTER NO MATTER WHAT (which happens *not* to be NAT in this exact context).

The joe six pack himself doesn't care, he just plugs the "magic box" that he got from his ISP, painstakingly copies the overly long password from the sticker on the back of the magic box (while cursing why isn't he allowed to use "Passw0rd!" as a passwrod. Com'on, there's even an uppercase and number), or simply flashes the QR-code from the OLED mini-screen (for the lastest generation of router that have one for that purpose).



They used to be a time when users did connect to the wild wide interwebs over an Analog Modem (those screeching boxes that you use to plug into your computer's COM port), or later ISDN Modem (no screenching, but basically the same). Back at the time, a computer thus connected was completely exposed to anything coming at it (Ah, the joys of a time when you could "winnuke" any computer on the net), and lots of software (FTP, IRC, direct file send in IM, P2P file sharing) counted on it.

So when xDSL arrived, I've seen lots of weird setups.
- xDSL *modem*. That plug straight into the USB port of the computer, and the computer gets a public address just like in the time of Analog/ISDN connections.

And that also includes weird routers :
- Router with USB (as a network device) and a single Ehternet port,
that did hand out a private address over DHCP to the computer,
BUT THEN DID A 1:1 STRAIGHT MAPPING between the public IP address and the private address of the computer.
(What was the name of this already? "cone NAT" ?)

- Same as above. Except that now the DHCP can hand out 3 other adresses (to plug a networked printer ?)
But still does straight 1:1 Mapping with the first address (printer doesn't need to have internet access at all, and the whole internet needs to be able to win-nuke the windows machine).
I still have such a useless junk from ZyXel collecting dust somewhere - it got used only a couple of hours, the time it took me to go buy something better.

So the reason current NAT'ing does security is because in addition of employing private address, it does sensible packet filtering (block inboud traffic, allows on-demand outbound traffic for all parties, requires manual TCP-forwarding configuration or UPnP to allow inboud traffic), but there exist asinine ways to do unsecure private addresse that used to actually exist in the wild.

Comment 99.9% (Score 1) 190

What you're describing is called a packet filter, not a router.

For 99.9% of the "average joe 6-pack" users, the packet filter is running inside [the linux kernel on the firmware of] their home DSL/cable/FITH router.

So yeah, for most of the clueless user who would be benefiting from NAT, they will be also benefiniting from the fact that the router sitting in their living room is doing packet filtering.

The "security" of NAT comes as a by-product of the fact that multiple devices NEED to be on a private RFC1918-style network (assuming we're talking typical consumer-grade NAT), and hence no single device does - by default - receive inbound traffic because they're not addressable in the first place.

And I'm telling you :
- you DO NOT need to be on an unaddressable private address (192.x.y.z or fxxx:::) to not receive any traffic.
The [packet filtering running inside the linux kernel in the firmware of the] router could be all the same blocking inbound traffic even if the target address happened to be addressable (e.g.: 2xxxx::: )

So please stop with this "NAT increases security".
It's the packet filtering that does.
And most sensible modern routeur (that have a not too much lousy firmware) do.

Comment So... (Score 1) 190

However, GP's point was that NAT could make it a little more difficult to get the device hacked in the first place.

So does also any sensible router that I've seen that blocks inbound traffic by default.
(i.e.: router where you explicitely need to open Internet->PC access).

It doesn't matter if they are private IP (v4) addresses, that need NAT and port forwarding (i.e.: port 8080 from the router, should be forward to port 80 on intenal sebserver 10.0.0.x),
or plain normal public IP (generally v6) addresses, that need simply to enable access to some ports on the public intenet (request for port 80 on machine IPv6 2xxx:yyyy:zzzz:wwww:vvvv:uuuu should be allowed through by the router).

If the router blocks inbound access by default, and the user needs to explicitely enable some access in the settings, both NATed IPv4 and IPv6 with public addresses are protected equally.

Comment What the end-user bought. (Score 1) 305

The thing is, from a technical point of view:

The user has paid for and bought.
- a car (with an electric drive, and it's battery)
- an expensive webcam (also, accompanied by some computation accelerating hardware that could run neural-nets/deep learning, if needed).

And the user has provably received the agreed goods.
(Easy to check, the front facing camera is clearly visible from the outside).

At some point in a putative future, Tesla might manage to write a pieces of software that could eventually make the cars 100% fully autonomous self-driving
(i.e.: Google-car style) and not only some advanced form of collision avoidance (what the current Tesla Autopilot is. Basically what Volvo, BMV, and the like have been providing for a decade, only a tiny bit more advanced. Basically, the same stuff as boat's or an airplane's autopilot - it takes over some of the more menial tasks of driving, but still require a human captain's supervision)..

They are now announcing that this future putative software that does not exist yet, can not by used to earn money.

From the current point of view : nothing could be done, because this thing doesn't exist yet.
So no legal argument at all.
It's basically as if I put a sign in my backyard saying that if one day, some extra-terrestials start to make contact, I will only allow *blue-colored* filying saucers to land here.

In the future: well *when* this putative piece of software starts to exist, then we will be able to start talking about it.
- maybe it will be considered as a software upgrade to which paying users should be entitled, because Tesla can't put legally enfocreable arbitrary limitation in their EUL (they probably just can't be held liable for any damage done in a commercial situation).
- maybe by then the law will have evolved and adapted enough, and people using 100% autonomous self-driving in a commercial manner will be legally required to take a special insurance that will cover any subsequent liability (that's probably going to be the case in some european jurisdiction).
- maybe by then, Uber will have *their own* neural net, and will require you to install *their* package and run *their* net when ubering an autonomous car, in order to keep the liability under control - e.g.: because they have correctly insured their neural net against commercial damage. (Given their tendency to try to wash their hands off, don't count on it, unless they get explicitly required by law).

Comment ASLR is *NOT* Obscurity, quite opposite (Score 1) 72

(Obscurity. You keep using that word, I do not think it means what you think it means)

ASLR is NOT obscurity.
ASLR is quite the opposite : it's a way to mitigate obscurity.

(Just like a password is NOT security through obscurity).

A kernel without ASLR is obscurity: you count on the attacker not known where the kernel (or any other critical software) stores its code.
Once the address map is known, every single instance of this kernel (or software) everywhere on planet Earth is at risk.

With ASLR (which is, in Linux kernel case, publicly documented and known - exactly as any cryptographic algorithme - the exact opposite of obscurity), every single instance can, based on a small random token (which plays the same role as a password or a private key in a cryptographic system), can manage to hide *its own peculiar instance of stuff* from a potential attacker.

Knowing how ASLR works isn't critical (and in Linux case, it's actually documented).
Knowing the token (=the password) is the critical step.
It's not "Security through Obscurity", it's side channel attack (= managing to guess the security key by using a feature of the Haswell CPU that locally leaks the information - the "clear text").

Security through Oscurity is hoping that nobody actually understands how your magical security solution works under the hood.
If anyone gets to know the internals, the *whole technology* is toast for ever.

Cryptography and other forms of sensible and modern security is the opposite: it counts on a technology that is as widely known and published as possible (so it undergoes as many tests and reviews as possible, to make sure it is sound).
If something is kept secret, it's a small token, a number, a code, a key. Just a piece of data. Not the actual open standard code which will process the data.

Comment Apple and ZFS (Score 1) 159

I'm betting that once Apple is done ridiculling themselves with their "too little, too late + NIH" catastrophe with APFS,
their probably going to silently acquire OpenZFS, and rebrand it as "Apple's CoW System".

I'm taking bets.

See Copland and NextStep for Apple's historical precedent.

(And see CUPS, LLVM, the KHTML-WebKit-Blink family, and countless of better external technologies that Apple ended-up buying/acquiring/taking over.
OpenZFS - if/when my prediction happens - will be just one extra point on this list)

Comment Apple's *New Future SSD filesystem* vs *Copland* (Score 1) 159

As pointed by krakelohm above,
and dgatwood below,
that "potential future successor to 'HFS Plus'" is NOT in production yet, and misses important features.

Let's be frank.

This thing is so much over-due, and has been post-poned so much, that it might as well be considered as Apple's new "Copland".

(And in this metaphore, ZFS is probably the thing that will play NextStep's role as the "external technology that got bought and hastily re-branded in order to save the situation in a last-ditch effort".
I'm starting to get bets).

Comment Remote exploit (Score 5, Informative) 72

TL;DR: because of this bypass ASLR cannot prevent local privilege escalation. but ASLR can still prevent remote access.

The point of ASLR is that it's not easy to determine where the functions are located in memory.

So, if there's an exploit where you can force code to jump at some specific point in memory, you cannot use this exploit to call the function you want because you don't know where they are.

(e.g.: stack smash. Overrun some temporary buffer that is stored on the stack buffer, up to the point where you can overload the return address. So once a function finished, it's doesn't jump back to the caller [it doesn't return] it jumps instead to the address you've overwritten [it jumps to the next function you want to abuse as part of you exploit] )

2 possible situations:

- You've already managed to get (user-level) shell acces (or at least run any payload of your choosing). You want to escalate privileges up to root. You know of a bug in some kernel piece of code that you can try to exploit. ASLR would prevent you from doing it because you don't know where the piece of code is exactly in kernel memory space. So you run the bypass proposed by the researcher and you obtain a list of where is what.
Now you can run your exploit, and gain root.

- You're outside the machine. You want to get remote access. You know a bug in some code (be it kernel or userspace) that could be exploited. But you need to jump into specific function whose precise location in memory you don't know because of ASLR.

So ASLR won't block local privilege escalation anymore (because when you have local access you could defeat ASLR's randomisations)
But ASLR will still block remote access (without local access, you can't get a map of all ASLR-ised functions you need to inject in your remote exploit).

Comment Mass data (Score 5, Informative) 159

All modern NAND flash memory does "quasi-RAID".

That depends 100% on the sort of controllers & memory layouts that are involved.

Do you have specific information that Apple does this? I don't.

Given that:
- nearly all modern smartphone/tablets/etc. do no go the extra headache to implement some weird custom solution for their mass storage.
- instead they all go for simple, standard, cheap of the shelf technology.
- [ BTW: eMMC (embed MMC - i.e.: an SD Card, without the plastic package, but directly available over an MMC bus) seems to be the most frequent solution ]
- Most of the flash anywhere, including thousands of SD Cards on the market right now, follow the exact same tendency: bigger model have more chips and can spread their write/erases among more chips ("quasi-RAID") giving better performance. That's why the "Class 10 UHS III" SDXC cards are only available on the bigger models, smaller models are slower. Same difference between microSDXC and regular SDXC cards (bigger cards can pack more chips and you have a greater choice of faster cards. At the micro level, it's only 128GB and above capacity that usually come with "Class 10 UHS III").
- Even more gory details if you care to read the benchmarked read/write speeds of each card. (again, more chips - found in larger package or bigger capacity - manage higher write/erase speeds).

Given all the above, there's high expectation that iPhones are following the trend..
But hey instead of speculating and calling each other names, let's check actual real heardware :
iFixit, Chipworks, SK Hynix Datasheet

What a surprise~ iPhone are exactly everyone else~ and source cheap of the shelf parts instead of re-inventing the wheel~~ Who would have though this~~~

iFixit's 32Gb iPhone use H23QEG8VG2ACS - a stack of 4 chips, with 256Gibits total (or 32GiB if used alone like in this phone).
Chipworks's 128GB iPhone use - a stack of 8 chips, with 1024Gibits total (or 128GiB when used in alone configuration)

So without even taking into account anything else, 32GB iPhone can only spread their writes among half of the chips available to a 128GB iPhone.
So they already start with a 50% malus at the hardware level.

That said, 128GB should only be 4 times faster than 32GB, so if these figures are correct then the 32GB units are also using lower spec memory.

Nope. At all. Like you said it entirely depends on the flash configuration. 128 isn't necessarily 4x more chips than 32.
Some constructor would go for 8x more chips of half the capacity.
In Apple case, they went for 2x more chips at 2x more capacity (more expensive but faster, enabling them to have bigger marging on the smaller/slower 32GB).

Which again goes back to the point of what I have posted... and this article.

Which goes back to the answer which you were given:
- YES, nearly every last constructor of flash is doing "quasi-RAID", i.e.: stacking/bonding more chips in the same package and spreading the write/erase among that.

That single fact can account for a huge part of the difference between models.

Then the thing is designed by Apple.
They run iOS on it. i.e.: the same "Darwin" core ( Mach microkernel + BSD monolithic kernel + BSD user space) as Mac OS X, only with a different interface.
They probably *still* use the same asinine file system as always HFS+
And that one is completely inadequate for flash.

It's a classical "inplace" writing file system.
This dramatically increase the "write amplification" typical with random-writes flash media. (each time you need to change some data, you would need to erase and re-write a whole block).
This probably *also* accounts for the dramatic performance difference in writing files.

Whereas the best with flash media would be to use a log-structured or copy-on-write filesystem. (Both approaches never over-writes previously written data)
Like :

- UDF (the number 1 most popular format on flash media that geek reformat for cross-platform)
- F2FS (designed by Samsung, and probably deployed on lots of android smartphones)
- JFFS (used on countless embed linux: like routers, e-readers, etc.)
- BTRFS (e.g.: Jolla uses it for their Linux phones)
- ZFS (...which Apple *STIL* isn't using)
and countless other (NILFS, LOGFS, JFFS2, etc.)

most of them are available on Linux, a few are available on Mac OS X.
But you can bet that iPhone are using none.

Comment Go back in time (Score 1) 348

you miss the point. The Tsara is WAY TOO BIG. If you throw it and it fails, then you are in deep trouble.

Then go back in time, and explain to the military that they don't need a huge powerful launch platform, but multiple smaller one.

Then maybe by now, the most normal way to do exploration outside the LEO would be to assemble the translunar/martian/whatever vessel in space, instead of throwing it from earth...

More seriously : you missed the point of the whole nuclear deterrent / MAD (mutual assured destruction).
The point isn't strategic targeting using nuclear head and precise tactical strikes.
The point is, once you press the big red button, basically the whole planet is toasted. Because at that moment, every one is going to press their respective button in retaliation.
And therefore (went the logic behind MAD) nobody will dare to be the first to press their button.

Comment Food chain. (Score 1) 156

On the other hand, the meat we eat has had to be fed quite a lot of time until the animal reached a good enough size and got slaughtered.
Thar's why more grains per kilogram of meat-food, than the equivalent grain-based dinner for the same human.

So not eating meat does decrease the amount of such harvesting accident for mice and and snakes (simply by needing less grain to feed the human, rather than needing more grain to feed the animal, until you have enough of the animal to feed said human).

(I personally happen not to eat a lot of grain (bread, pasta, and other carbohydrate food) anyway... so I can be proud to cause a little bit less combine-induced cruelty to mice and snake... at least toward them...)

Comment Fake soy meat (Score 1) 156

This is not fake soy meat or whatever.

That's something I've never understood.
Tofu shaped like meat. It only taste like shit.

It's as if its only purpose is to be shaped like a sausage, so you don't feel outcast when you're on a diet but get invited to a BBQ, you still have a sausage-shaped object to put on the fire like everyone else.

To me this would sound just as mush stupid, if some butchers started to make redmeat shaped in the form of a red peperrni, so on the day you crave meat but were invited to a BBQ at some tree-hugin hippie vegans, you don't feel outcast and have a veggie-shaped object to put on the fire.

Stupid. Fake. Meat.

Even more so when the human culture DOES HAVE some very nice traditionnal cuisine which is tasty but is also meat-free.
(in India and in the middle east you can find quite a lot ot veggie dishes which actually taste good. Unlike the tofu sausages).

Comment Base use (Score 1) 266

There's a difference of design and purpose of these object.

Lawn darts are basically like scissors.

Lawn darts have a pointy bit, that might get dangerous when use unsupervised.
But they have a use: they are toys, designed for play. Most of people will use it to play, most people will be successful at playing without getting hurt.

(Just like scissors have a sharp edge that could get people hurt. But scissors are extremely useful tools, so they won't get banned)

A kid with a bazooka doesn't serve any purpose. A bazooka is a weapon designed to bring destruction and/or death.
Though some extremely creative (or deranged kid) might be succesful at designing a fun game around one, that's not their typical use.
(Same also why some people, specially people living in the safer parts of the world like me, don't really see the point of needing to own guns).

That's why you're likely to find very few people complaining about the ban on giving their kids bazookas, whereas you'll constantly see people complaining when some random toy they've used to play with when they were kids is suddenly considered too much dangerous and gets banned (like Kinder Suprise chocolate eggs).

Comment ...and OIl !! (Score 1) 348

Fine. Whatever. Let's militarize Mars. We can install a fuckin particle cannon on it. Now you have your reason to go.

Oh, and we could persuade the politician that there's also a lot of oil to annex... sorry... to bring democracy to on Mars !
That's also going to boost the space program.

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