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Comment by justinschuh | Hacker News Reader

You're very confused about these technologies. NaCl and ActiveX aren't even remotely comparable. ActiveX is a method for deploying arbitrary binaries via the Web, and history showed it to be extremely dangerous. NaCl is a method of running thoroughly sandboxed native code; because NaCl is machine specific, it's deployed only through Chrome extensions/apps, and there's no intention to expose it directly to the Web. PNaCl adds a portable bytecode layer on top of NaCl, and is intended as a general Web technology. Realistically, it's more comparable to Java or .NET, only lower-level, more performant, better security, and no one's going to get sued for using it.

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Not quite, and I'm not confused.

Both have sandboxes (ActiveX since Windows 6.0, IE7), both have restricted APIs, both run native code.

PNaCl is equivalent of silverlight which is cut down CLR.

More performance - I doubt it. CLR+JVM is pretty much up there. The moment you add any virtualization, trap code or translation layer to native code via NaCl which you will require for security, there is going to be overhead which will knock it inline with a VM architecture. Startup time might be less - that is it.

Better security - that's a lie. Virtualization on any layer never gave anyone better security. It's throwing stones in glass houses. The only hard security boundary is at the MMU/page table. As NaCl grows, you will see it break.

No-one getting sued? I'm sure the EU will have something to say when no other vendor implements it and Google uses it to leverage market share, much like Microsoft did in the late 90's and early 00's.

I'm sorry, but you are so grossly wrong in your statements that the only valid response is a bit of a fisking. Normally I'd prefer not to respond this way, but I've already engaged you, and I can't really let this much misinformation stand.

> Both have sandboxes (ActiveX since Windows 6.0, IE7), both have restricted APIs, both run native code.

ActiveX is a general purpose object API and has no sandbox at all. IE 7+ on Vista+ can instantiate ActiveX controls in a weak sandbox via low-integrity mode, but to imply it's comparable to the NaCl sandbox is just comically ignorant. NaCl validates the nexe's conformance and its subset of x86 instructions before it will run it (in that way being very similar to Java and .NET CLR). And NaCl runs entirely in an outer, system-level sandbox that denies all system and object access.

In contrast, IE's low integrity mode lets you read anything the user can, exposes massive chunks of the system as attack surface, and provides various writeable locations. On top of that, all non-trivial ActiveX controls in IE implement brokers which run fully outside the sandbox--something that's not even possible with NaCl.

> PNaCl is equivalent of silverlight which is cut down CLR.

Nope. And making that claim begins to underscore just how little you know about this.

> More performance - I doubt it. CLR+JVM is pretty much up there. The moment you add any virtualization, trap code or translation layer to native code via NaCl which you will require for security, there is going to be overhead which will knock it inline with a VM architecture. Startup time might be less - that is it.

Virtualization or trap layer? That's not even close to how NaCl works. It's really sad that you couldn't be bothered to read a one-page explanation of before you launched into this completely wrong-headed diatribe. Please, start here next time, so your trolling can at least be superficially informed: https://developers.google.com/native-client/overview

> Better security - that's a lie. Virtualization on any layer never gave anyone better security. It's throwing stones in glass houses. The only hard security boundary is at the MMU/page table. As NaCl grows, you will see it break.

Once again, premised on your total ignorance of the subject matter. Come back when you have at least a basic knowledge of the thing you're criticizing.

> No-one getting sued? I'm sure the EU will have something to say when no other vendor implements it and Google uses it to leverage market share, much like Microsoft did in the late 90's and early 00's.

I'm sure there was an attempt at making an argument in this last line, but mostly it just seems to be randomly scrambling for scary sounding words.

Excuse my ignorance on the matter but you make yourself look immature, arrogant and patronising and this does no credit for your project or yourself.

So basically, NaCl:

1. Validates the binary image. Of course that validation has no holes in it. When it does it...

2. Stops unsafe operations. Of course it never misses any and knows every instruction side effect...

3. Oh wait...

I'd put cash on someone breaking the sandbox, I mean after all it's perfect isn't it:

http://www.matasano.com/research/NaCl_Summary-Team-CJETM.pdf

You can't build a flawless sandbox on top of a system by closing the holes one by one, especially on x86/x86-64. The number of edge cases is immense.

I'm sorry if you feel slighted, but I'm only attempting to dispel your ongoing stream of misinformation. And even after being corrected, you've persisted to the point where it's hard to perceive your behavior as anything short of intentional malfeasance.

As for the strawman in your latest comment, no one made any claims of "a flawless sandbox." I rightly pointed out that the security model of NaCl is far more robust, and you've offered nothing to counter that. Now, of course, software is going to have bugs, and the ones listed in that paper are significant. Fortunately, no combination of those bugs could have breached the outer sandbox, and would not have represented a real-world system compromise.

The origin of that paper also circles back to a very important point. We realize that we need to attack security from many different angles (fuzzing, sandboxing, bounty programs, etc.). And that paper you cited was actually the result of Google sponsored competition in 2009 against a pre-release version of NaCl. The authors were the second place winners, and have continued to research NaCl's security both as independent researchers and paid consultants. (One of them is actually presenting at Black Hat on NaCl security this week.)

My point here is that an objective read of the paper really paints NaCl very positively from a security perspective. Had you actually looked at the content rather than just made an assumption based on the title you would have been aware of that.

The real problem with ActiveX wasn't the technology, it was the API. Code relied on a large, complicated, ever-changing API which was practically impossible for others to duplicate. Win32 was for the most part documented, but even a decade later Windows XP programs are often not useable in WINE.

This is the same problem with NaCL. The API is complicated and has a bunch of browser-specific features. Firefox can't just include "pepper.c" and have NaCL support, there's tons of work involved. One result is that Firefox won't support Flash for Linux anymore. Implementing Pepper, even though it's "open source" is more of a hindrance than not having Flash.

NaCL is better technology than ActiveX, but uses the same idea of leveraging a OS/browser-specific API as a handicap for competitors.

The earliest versions of NaCl attempted to align to the mess that is NPAPI, but that was literally years ago. For the last few years NaCl has used PPAPI, which is well-defined, more loosely coupled to the web, and has a clean versioning mechanism: https://developers.google.com/native-client/pepperc/

I see hundreds of APIs and beta APIs. There's no source code repository. The python scripts to download a SDK refer to Google "private_svn".

So Google spends 6 months working on the next version and Firefox and Opera don't even get access to it until the next SDK and are 6 months behind, and they have zero input in how it evolves. That's not how open source should work.

Ummm, what?

http://www.chromium.org/nativeclient/pnacl/building-and-test...

Source: http://src.chromium.org/viewvc/native_client/trunk/src/nativ...

That wasn't hard to find.

Your "source" link doesn't have source, see:

http://src.chromium.org/viewvc/native_client/trunk/src/nativ...

The other is a link to a build of pnacl sdk that also doesn't include source (src/ folder is empty).

Am I being dense here? Where's the hg, github, code.google link that actually has the source code? I couldn't find where the source is. You would think that would be pretty obvious for an open-source project, like maybe some giant button on the project page.

Anyway it doesn't change the point. This isn't being developed as a public open-source project. It isn't designed to be easily added to browsers other than Chrome. Like ActiveX, it's being used as leverage to make one browser better at the expense of others.

Looking at the code, you have to check out the source and then run another script to check out the source from Google's private source control system/depot.

Why it isn't just in a public repo, I don't know. It looks like it is set up so they can pull it at a moment's notice.

I agree with your comments.

This is just silly. You can't say that you can pull the code from a public repository, and then claim it's private. If it's set up so you can pull the code, and you do so successfully, then it's by definition public. It's totally understandable that you're unfamiliar with how the the projects and dependencies are distributed. The Chromium projects are one of the largest and most complex codebases you're likely to encounter. However, it's all clearly documented and public, with numerous open source contributors. So, it's very disturbing that your first thought is not try and learn why, but rather to insinuate some irrational conspiracy theory.

Sorry I will clarify with a genuine question: where is the public source code with changelog?

It seems like a snapshotting tool, so you check out the stub and then dump the snapshot into it from the depot.

(this is similar to how Windows is built inside Microsoft).

Just follow the instructions for checking out and building NaCl: http://www.chromium.org/nativeclient/sdk/howto_buildtestsdk

Everything is in public svn and/or git repositories. The thing that's confusing you is probably how modules are split out as dependencies. They're not checked directly into the tree, and instead are listed by repository URL and pinned revision in DEPS files. On checkout and sync gclient pulls the correct revision from the appropriate repository: http://dev.chromium.org/developers/how-tos/depottools#TOC-DE...

I can appreciate that you're unfamiliar with the build and dependency management tools used by Chromium and related projects. However, it's disingenuous to imply that somehow the project is any less public or open because of that.

Some dependencies are pulled in and set-up by the checkout scripts, which is not an unusual degree of complexity for a large group of projects with such broad dependencies. It's all clearly documented and everything you need to know to checkout, build, and contribute code is linked from right here: http://www.chromium.org/nativeclient

I think you pretty much proved my point. NaCL is a sandbox, the very thing that should have the cleanest, clearest delineated lines. But there's no standalone version, no stub version. And you seemingly need a PhD in Chromium to even find the source much less get it working in anything else.

I guess Mozilla is unusually capable then because their download link is right here:

https://developer.mozilla.org/en/Mozilla_Source_Code_%28Merc...

Pretty simple.

So you're working on Chromium and think navigating a buildbot to get python scripts that download from a private svn is not unusual... ok fine, but don't be surprised if people don't want to touch it (or even can figure out how to). I certainly understand better now why Mozilla would rather just drop Flash support.

So, the new claim is that making a directory and running a script is too hard for you: http://www.chromium.org/nativeclient/sdk/howto_buildtestsdk

Seriously, this is just absurd. I don't know what you think you're arguing at this point, but I don't have the energy to correct you anymore.

I don't understand your argument here. NaCl is an open source and openly developed project that anyone is welcome to participate in. The repository, tracker, and mailing lists are all public. In fact, the NaCl team has made numerous efforts to involve the other browser makers (even if they haven't shown interest so far).

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