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How a web app can download and store over 2GB without you even knowing it

jclaes.blogspot.com

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Re: How a web app can download and store over 2GB without you even knowing it

#3
post #2

This is not an issue in either Opera or Firefox. The title should probably reflect that it's limited to Chrome (and possibly other Webkit browsers + IE?).

Why is not an issue in Opera and Firefox? Do they have smaller maximum caches? Or do they notify you of the background transfers?

Re: How a web app can download and store over 2GB without you even knowing it

#4
post #3
post #2

This is not an issue in either Opera or Firefox. The title should probably reflect that it's limited to Chrome (and possibly other Webkit browsers + IE?).

Why is not an issue in Opera and Firefox? Do they have smaller maximum caches? Or do they notify you of the background transfers?

the default local storage limit for Firefox is 5 megs per domain.

Re: How a web app can download and store over 2GB without you even knowing it

#5
post #3
post #2

This is not an issue in either Opera or Firefox. The title should probably reflect that it's limited to Chrome (and possibly other Webkit browsers + IE?).

Why is not an issue in Opera and Firefox? Do they have smaller maximum caches? Or do they notify you of the background transfers?

I don't think either notifies you about the background transfers, but e.g. Operas default cache limit for Application Cache is ~50 MB according to http://www.opera.com/support/usingopera/operaini/.

Re: How a web app can download and store over 2GB without you even knowing it

#8
post #6

It would be fun to execute this against a mobile device, where storage is expensive. 2GB might be all that is required to choke the device. A neat client-side DDoS :)

iOS (and Android I think, but I primarily dev iOS so that's where my knowledge is) won't let a website exceed a 5MB local storage limit without explicit user consent...so I suppose still technically possible, but not without getting the user to agree to it first.

Re: How a web app can download and store over 2GB without you even knowing it

#9
post #6

It would be fun to execute this against a mobile device, where storage is expensive. 2GB might be all that is required to choke the device. A neat client-side DDoS :)

I think Opera Mobile shouldn't have this cache problem either, similar to my comment about the desktop version. The default cache limit in Opera Mobile is ~2 MB.

I _believe_ that both quotas can be increased after confirmation from the user, but I haven't made any tests.

Re: How a web app can download and store over 2GB without you even knowing it

#10
post #3

Earlier quoted context omitted.

Why is not an issue in Opera and Firefox? Do they have smaller maximum caches? Or do they notify you of the background transfers?

the default local storage limit for Firefox is 5 megs per domain.

Sorry for nitpicking, but I think local storage is a part of Web Storage (http://dev.w3.org/html5/webstorage/), and not Application Cache (http://www.whatwg.org/specs/web-apps/current-work/multipage/... or http://dev.w3.org/html5/spec/offline.html).

I think that the Application Cache quota is not strictly connected to the local storage and session storage limits.

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