Slashdot Mirror


Google x86 Native Browser Client Maybe Not So Crazy After All

GMGruman writes "Google's experimental technology to run native x86 binaries in the browser shows lots of potential, writes Neil McAllister. He's previously said it was a crazy idea, but a new version of Native Client (NaCl) caused McAllister to take a fresh look, which has led him to conclude the technology is crazy like a fox. McAllister explains what NaCl is useful for, how to use it, and why it's not a Java or a Flash or a JavaScript replacement, but something else."

24 of 332 comments (clear)

  1. Not Java, more like Active X by Anonymous Coward · · Score: 3, Informative

    Hopefully Google will make this more secure than ActiveX.

    If Android is any indication of Google's commitment to security, a free wallpaper application will be able to read all your text messages and track your location in real-time.

    1. Re:Not Java, more like Active X by WrongSizeGlass · · Score: 5, Funny

      Now all they need to do is give it full access to the Windows Registry and we'll be right back to where we started.

    2. Re:Not Java, more like Active X by Enderandrew · · Score: 4, Informative

      Chrome is extremely sandboxed. Scripts running in Chrome don't have permission to randomly alter files, install software, etc. like ActiveX did.

      I imagine they'll keep NaCl in a similar sandbox.

      --
      http://blindscribblings.com - Tasty pop-culture in conceptual fashion.
    3. Re:Not Java, more like Active X by Goaway · · Score: 4, Insightful

      I don't see how it could be made secure at all

      This may have something to do with you not making any effort whatsoever to read up on what NaCl actually does.

    4. Re:Not Java, more like Active X by Goaway · · Score: 3, Informative

      Chrome sandboxes its own native executable code, not just Javascript.

      Also, NaCl is even more strictly controlled than just a sandbox.

  2. NaCl + GAE by rumith · · Score: 3, Interesting

    Can't wait for this thing to get hooked to App Engine once they are both stable enough. The results will likely be breathtaking, to say the least.

  3. this is a terrible idea by digitalsushi · · Score: 5, Funny

    I am qualified to comment because I have skimmed the article summary. Furthermore, I know perfectly well that any time a browser allows for new features, it's a way to get hacked by eastern bloc countries. Finally, I can't remember why I was angry in the first place, but I can guarantee you that if whatever it was is also the reason the honeybees have been dying off. I am getting so sick of this stuff!

    --
    slashdot: where everyone yells sarcastic metaphors to themselves to understand the issue
  4. ActiveX revisited? by H0p313ss · · Score: 5, Insightful

    So a proprietary, but open SDK to run native binaries on one vendors browser. What could possibly go wrong?

    I hope Google put a heck of a lot more effort into security/sandbox issues than Microsoft did or I'm going to have to start telling people to never install Chrome. ActiveX was the best attack vector for Windows for the longest time, and as far as I know it's still pretty effective against the great unwashed who will click anything to make a dialog go away.

    --
    XML is a known as a key material required to create SMD: Software of Mass Destruction
    1. Re:ActiveX revisited? by TheRealMindChild · · Score: 4, Informative

      That is because ActiveX is just a DLL. Loading an ActiveX library is just loading a DLL. It isn't ActiveX that is the problem, but the fact that you are allowing any site to install and run a DLL. You don't even need to load your own anymore. Just have a handy exploit for Adobe Flash, load random flash object to make sure the browsing party has the DLL(s) installed and loaded, then exploit Flash. Same goes for Java. And that zynga "helper" you have from Facebook...

      --

      "When life gives you lemons, don't make lemonade. Make life take the lemons back!" -- Cave Johnson
    2. Re:ActiveX revisited? by Anonymous Coward · · Score: 4, Informative

      If you follow up on what this actually means in practice, the way these native modules are loaded is in a sandboxes process that disables all access to system calls (file read write, dll hooks, new process execution, etc). The modules interact through a "simple IPC" mechanism that is allegedly easy(er) to secure than arbitrarily complicated code.

      ActiveX had no such sand boxing restrictions. ActiveX was closer to browser plugins in that they have complete, pretty much unrestricted access to the system.

      Start here on the sandbox process:
                - http://www.chromium.org/developers/design-documents/sandbox
                - http://www.chromium.org/developers/design-documents/sandbox/Sandbox-FAQ

      If this works as advertised (is actually safe), I would expect the general architecture to be adopted across any piece of software that speaks on the network (i.e. complex protocol parsers and validators in a sandbox).

    3. Re:ActiveX revisited? by suy · · Score: 4, Interesting

      You probably should start reading about it first, please. The browser doesn't allow you to run native binaries of the system, or native code in general. It allows you to run very constrained routines in assembler code, but a very limited set of instructions, only the ones that can be secured enough. That's why you need an specialized SDK: the generated binaries have to use a very reduced set of machine instructions.

      The great benefit of this, is that the generated ".nexe" files are portable accross operating systems. Basically, is a way to run heavy routines in C/C++ instead of JavaScript. The API is limited too.

      It's pretty cool in the sense that you could do fancy graphics or UIs without Flash or Silverlight. You could write them in Qt or GTK+ or SDL, and the generated executable works on every OS (you'll need a recompile for ARM phones though).

      If it can be refactored to a plugin for every browser, this will be the best Flash/Silverlight killer ever.

  5. Light on details by pclminion · · Score: 4, Informative

    The article is light on details, but they do say that the executables are contained in .nexe files which are apparently NOT your run-of-the-mill PE format, so they can't just execute from a double click. And they do say that there's this annoying multi-second lag as the thing fires up. From this, I assume they are doing dynamic code instrumentation to implement whatever security measures they have in place.

    If done correctly, this can be secure. I've been working with Intel's Pin library a lot lately, mostly for security-related projects. With these sorts of things you can intercept all memory accesses, function calls, system calls, instrument and analyze arbitrary instructions in arbitrary ways, etc. Again, if done correctly a dynamic instrumentation approach could make this idea viable. But you'd need a very skilled team to do it right.

    1. Re:Light on details by slart42 · · Score: 3, Interesting

      NaCl in it's current implementation is not JIT compiled. It is actual compiled native x86 (or x64 or arm) code running in a secure sandbox. What causes a delay is the Validation of the code, ie, the code has to meet certain requirements to be secure. That said, Google has plans for PNaCl, "portable" nacl, which indeed uses LLVM bytecode, making it a JIT implementation. Why not just use JavaScript? Having access to a lower level language and to being able to reuse tons of existing code is a big plus. Think porting existing game engines to the web.

    2. Re:Light on details by pclminion · · Score: 3, Interesting

      How well does the validation engine cope with code that's deliberately obfuscated? I don't know for sure, but I suspect that proving code is safe using static analysis is probably NP-complete. Dynamic instrumentation would make it much easier to implement sandboxing -- all operations which aren't explicitly permitted are forbidden, and you simply stop the code when it tries to do one of those forbidden things.

    3. Re:Light on details by Trepidity · · Score: 3, Informative

      Doing it optimally probably isn't possible, but you can statically transform code so it's guaranteed safe by doing somewhat pessimistic transformations, things like replacing every store instruction with a sequence of "safely store" instructions. As long as the analysis and transformations are at the assembly level and don't require recognizing higher-level patterns, obfuscated code isn't really an issue; the main issue is making sure you correctly analyze what safe and unsafe asm instructions are, and what transformations are guaranteed to result in safe code.

      There's a nice writeup here of how they do the transformations on ARM.

  6. Re:NaCl? by Tr3vin · · Score: 4, Funny

    Yes. The media framework (audio, OpenGL, etc) is called Pepper.

  7. NaCl is very useful... by coolmoose25 · · Score: 3, Informative

    I use it all the time... I put it on french fries. I spread a lot of it on my driveway and sidewalk this year. The only real drawback is the high blood pressure that can result if you consume too much of it.

    --
    Brawndo: It's what plants crave!
  8. Re:this is *not* a terrible idea by djbckr · · Score: 3

    I too am qualified to comment. I'm not fully convinced it's a great idea, but I like the idea of running "next to the hardware" code in a sandbox (the browser). It's sort-of the best of virtualization (sandbox, controlled by the browser) and C-style performance.
    I don't see this as something that would be extensively used on a lot of web sites, and there are potential security issues that need to be scrutinized, but it's another tool available to developers. I like it.

  9. Re:Why???? by Ancantus · · Score: 5, Interesting

    If you havn't noticed, one of Google's intents is to make the browser you go-to place for all your needs (kinda makes sense with their business plan). And honestly i think that it is a worthy goal. This way people can make cross-platform applications and a way to distribute them all on one platform.

    --
    Violence is the last refuge of the incompetent. -- Isaac Asimov
  10. Like Java, without the JVM by Animats · · Score: 4, Informative

    That's been around for a while. x86 machine code has to be written in a special way which prevents certain problems, such as buffer overflows into return addresses. Google has a modified GCC for this. Read the research paper. It uses the rarely-used segmentation protection features of x86 CPUs to help provide an inner section of sandboxing. That's not enough, though; static analysis of the code, to check that all branches go to valid instructions, is necessary. This works much like the Java byte code verifier, the checker that runs as Java code loads. All returns and calls have to go through some extra code to insure that control goes where it is supposed to.

    The 64-bit extensions to the x86 instruction set don't have the segmentation machinery. The AMD designer of that mode once told me "nobody uses that". So this approach doesn't translate well to 64-bit code, and all code under this system runs in 32 bit mode.

    This comes with an API and an OS shim. Executable modules can make about a hundred system calls, which are portable across Windows and Linux. In the original version, you couldn't get at the graphics hardware, so it wasn't a suitable delivery mechanism for games. But now, Google has a connection to OpenGL in the thing. That makes it more useful. Games with full system performance could be delivered through this approach, while appearing to run within the browser. The performance is about 90 to 98% of unprotected code.

    It's very clever, and a good idea from a security standpoint. Untrusted processes communicating through narrow interfaces are always a good thing from a security perspective. The problem is that it doesn't solve a problem that anybody really seems to have - there's little demand for higher performance apps in the browser.

  11. I really wish... by Spazmania · · Score: 5, Insightful

    I really wish folks wouldn't intermix this crap with a web browser. I'm all for having some kind of a cloud browser for accessing Internet-based applications with the client running java or nacl or whatever. But when I'm surfing the web looking at untrusted sites, I don't want ANYTHING running browser-side. Not even javascript.

    --
    Moderating "-1, Disagree" is simple censorship. Have the guts to post your opinion.
  12. Re:Like ActiveX? by drspliff · · Score: 4, Informative

    The Java sandbox was at the interpreter level and did not provide protection at the OS level. The google native client stuff sandboxes it at the OS level and only allows for communication via RPC calls to the parent app (e.g. drawing on a canvas), much like the seccomp approach for Linux which is a true sandbox

  13. Crazy smart ISA portability by simula · · Score: 3, Informative

    Native Client was designed to easily allow portability across all popular current platforms using cross-compilation. On a single development machine you can currently build executables for x86-32, x86-64, and arm. There is currently support for Windows, Linux, and OSX. Here is an article on the generals.

    Much more excitingly though, the team is working hard on integration with LLVM so that you will be able to compile your application into a single LLVM bytecode package. This bytecode would then be sent to any current or future architecture and the final compilation step would occur on that architecture. Here is a pdf concerning that effort.

    You are also significantly underestimating the effort that they have put into this BSD licensed project.

  14. Re:NaCl? by Tr3vin · · Score: 5, Informative

    While I appreciate the funny mod, it wasn't meant as a joke. http://code.google.com/chrome/nativeclient/docs/reference/pepperc/index.html