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Comment by rurounijones | Hacker News Reader

What whitelist?

JS Execution? No popup blocking? Something else?

Did a bit of digging - it lets NACL apps downloaded from those whitelisted Google apis have access to "dev interfaces". Brief search shows that these dev interfaces would have the ability to access the user's PC outside of the Chrome sandbox.

In effect, this gives Google remote code execution rights from their domains on anybody running Chromium.

With DNS hijack, everyone can remote execute.

No, HTTPS only. So probably only Google or the NSA, I guess.

Well, it's not like you can't buy a valid certificate for google.com from a turkish CA that is trusted by all browsers... This has happened before, the only question is how much you're willing to pay.

There's also hardcoded HSTS pining for Google certificates, preventing this.

How does HSTS deal with expired certs?

> Brief search shows that these dev interfaces would have the ability to access the user's PC outside of the Chrome sandbox.

Aren't they just the APIs in https://code.google.com/p/chromium/codesearch#chromium/src/p...? By the looks of it they're just things that aren't ready for primetime, not things that are special dev-only debug tools or whatever.

Well there is

https://code.google.com/p/chromium/codesearch#chromium/src/p...

and

https://src.chromium.org/chrome/trunk/src/ppapi/c/extensions...

I haven't looked deeply, but both seem to allow for access outside the sandbox. Maybe a chromium committer could give more detail on the safety of the dev interfaces. They are blocked from public usage for a reason though.

which parts of the above code/api allow access outside of the sandbox?

Eh, using structs for namespacing in C. I hadn't seen that in a while.

They don't enable access outside the sandbox and should be pretty safe.

PPB_Testing_Dev is a set of helpers for writing tests: querying status of the plugin; running nested message loop to wait for results of async operations; simulate input events which are received only by the plugin itself.

PPB_Ext_Events_Dev is for registering/unregistering events provided by Chrome apps apis (http://developer.chrome.com/apps/api_index.html). It will only be accessible when the NaCl module is included in a Chrome app. This interface hasn't been implemented yet.

I only use Chrome to access Google apps/docs/gmail, since it seems to work better than other browsers for this. Looking like it might be worth setting up a VM appliance for this now.

Firefox is more performant on my Ubuntu box than Chromium, even for things like Gmail and Google Docs.

> In effect, this gives Google remote code execution rights from their domains on anybody running Chromium.

If you're running Chrome, you've already given them code execution rights – the only thing this does is make it slightly harder to detect.

To me, it looks like they are allowing https @ plus.google.com, plus.sandbox.google.com, ssl.gstatic.com, talk.google.com, talkgadget.google.com, and ssl.gstatic.com to use WebUIs (most likely Dart web apps) [1] and NaCl [2].

  // Temporarily allow these whitelisted apps and WebUIs to use NaCl.

> Google Native Client (NaCl) is a sandboxing technology for running a subset of Intel x86 or ARM native code in a sandbox. It is proposed for safely running native code from a web browser, allowing web-based applications to run at near-native speeds,[2] which aligns well with Google's plans with Chrome OS. It may also be used for securing browser plugins, and in the future parts of other applications or full applications. [2]

[1] https://www.dartlang.org/articles/web-ui/

[2] http://en.wikipedia.org/wiki/Google_Native_Client

Just a guess but there's a comment:

// Temporarily allow these whitelisted apps and WebUIs to use NaCl.

And it's in a function called "IsNaClAllowed"

I am not 100% familiar with NaCL but it this a download / install whitelist then for NaCL programs?

[EDIT] answered by https://news.ycombinator.com/item?id=6723930

Looks like it's a whitelist for Native Client.

      // Temporarily allow these whitelisted apps and WebUIs to use NaCl.

For NaCl, presumably.

The function name is "bool ChromeContentRendererClient::IsNaClAllowed", so I guess that.

Reply on news.ycombinator.com