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From Shazron <shaz...@gmail.com>
Subject Re: API function: Open url in system web browser
Date Sun, 20 May 2012 09:41:59 GMT
e.g.
<script src="http://evilsite.com/stealmydata.js?_cordova_target=foo"></script>

this already escapes the whitelist in your proposal. And your
proposal, for it to work, will need this whitelist exception.

On Sun, May 20, 2012 at 2:38 AM, Shazron <shazron@gmail.com> wrote:
> On Sun, May 20, 2012 at 12:43 AM, Brian LeRoux <b@brian.io> wrote:
>> How is opening a URL in a web browser a security risk to the Cordova code
>> shaz?
>
> By opening up the whitelist to exclude urls that have the query param,
> which your proposal requires, it allows malicious code to bypass the
> whitelist by just including this query param. Not through an anchor
> tag perhaps, but through ajax calls. The whitelist intercepts all
> network connections.
>
>>
>> Jesse: a declarative approach just means devs need to manually add the URL
>> param themselves (quirk). A fair trade while we wait for the beefier
>> programmatic child browser API.
>> On May 20, 2012 6:45 AM, "Shazron" <shazron@gmail.com> wrote:
>>
>>> Jesse, I understand the problem, I know what Brian is asking, I'm
>>> afraid no one does understand with regards to the two request problem.
>>> I was afraid someone would "go there" and suggest to compromise the
>>> whitelist. This is a security problem if we allow any url with
>>> _cordova-target= to circumvent the whitelist check, think about it -
>>> it's a big hole.
>>>
>>> On Sat, May 19, 2012 at 8:12 PM, Jesse <purplecabbage@gmail.com> wrote:
>>> > Shaz: I believe Brian is proposing you look for urls
>>> > containing _cordova-target= before rejecting them via the whitelist.
>>> >
>>> > IMHO: The discussed solutions resolve to the same thing, it is just a
>>> > semantics discussion.
>>> >
>>> > Given the following html placed in the document by the developer:
>>> > <a href="http://somwhere.com" target="_blank">asdf<a>
>>> >
>>> > Providing a new API means the link becomes (or something similar):
>>> > gap://app/openExtUrl/http%3A%2F%2Fsomwhere.com
>>> >
>>> > Brian's proposal means the link becomes :
>>> > http://somwhere.com&_cordova-target=blank
>>> >
>>> > So either native code has to watch for links with '_cordova-target=' or
>>> > just handle another cordova command.
>>> >
>>> > Both solutions require re-writing urls on page load, or on dom change.
>>> >
>>> > Andrew's earlier suggestion added a document level click handler that
>>> would
>>> > determine if the clicked item was an <a> and do the right thing based
on
>>> > it's attributes, which I think has some merit in that it handles dynamic
>>> > content, and it doesn't modify it, it just observes it.
>>> >
>>> > I will be thinking more on this and adding my recommendation in a while
>>> ...
>>> >
>>> >
>>> >
>>> > On Sat, May 19, 2012 at 7:43 PM, Shazron <shazron@gmail.com> wrote:
>>> >
>>> >> No. Read it again, especially the two request part. For urls NOT in
>>> >> the whitelist, the first request will be rejected by the whitelist.
It
>>> >> won't work.
>>> >>
>>> >> On Sat, May 19, 2012 at 7:34 PM, Brian LeRoux <b@brian.io> wrote:
>>> >> > Ok, so read that, its referring to the target attribute but it
looks
>>> >> > like you can check stil check for a url parameter on an NSURLRequest
>>> >> > [1].
>>> >> >
>>> >> >
>>> >>
>>> https://developer.apple.com/library/mac/#documentation/Cocoa/Reference/Foundation/Classes/NSURLProtocol_Class/Reference/Reference.html
>>> >> >
>>> >> > So what I'm proposing is this: cordovajs walks the dom finding
all
>>> >> > anchors with a target attribute and adds something like this to
the
>>> >> > href:
>>> >> >
>>> >> > <a href=http://somwhere.com&_cordova-target=blank
>>> target=blank>asdf<.a>
>>> >> >
>>> >> > Then, when clicked, touched, whatever, you capture if the URL
>>> >> > parameter named _cordova-target exists. If it does, spawn browser.
>>> >> >
>>> >> > Dynamic links would be missed. I think thats an ok/fair quirk.
If
>>> >> > wanted to be aggressive we *could* watch for dom mutation events
and
>>> >> > solve that too tho I suspect it would not help performance!
>>> >> >
>>> >> >
>>> >> > On Sat, May 19, 2012 at 6:00 PM, Shazron <shazron@gmail.com>
wrote:
>>> >> >> When JIRA is back up (it's under maintenance right now), see
my
>>> >> >> first/second comment on this issue:
>>> >> >> https://issues.apache.org/jira/browse/CB-362
>>> >> >>
>>> >> >> It's a bit too long to rehash :)
>>> >> >>
>>> >> >> On Sat, May 19, 2012 at 8:17 AM, Brian LeRoux <b@brian.io>
wrote:
>>> >> >>> Sorry shaz, I must be dense but I missed the technical
reasons?
>>> >> >>>  On May 19, 2012 11:48 AM, "Shazron" <shazron@gmail.com>
wrote:
>>> >> >>>
>>> >> >>>> > The method I'm proposing
>>> >> >>>> > assumes all link events are trapped, inspected
for a url param,
>>> and
>>> >> in
>>> >> >>>> > its absence, falls back to default behavior. Maybe
thats not
>>> >> >>>> > realistic. Seems like both iOS and Android do
not trap the target
>>> >> >>>> > attribute. Which means we'd need to add a url
param so that trap
>>> is
>>> >> >>>> > caught.
>>> >> >>>> >
>>> >> >>>>
>>> >> >>>> It is not entirely a question of "nastiness" in adding
a url param
>>> >> >>>> with regards to why it won't work in iOS (although
imo I don't like
>>> >> >>>> it) - I have already presented valid technical reasons.
>>> >> >>>>
>>> >> >>>> With respect to achieving all our goals - not introducing
a new
>>> API,
>>> >> >>>> and fixing this bug that sorely needs fixing - ChildBrowser
like
>>> you
>>> >> >>>> proposed is the better bet then. So what should be
the plan for
>>> this?
>>> >> >>>>
>>> >>
>>> >
>>> >
>>> >
>>> > --
>>> > @purplecabbage
>>> > risingj.com
>>>

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