1212657 - Firefox and Flash do not play nicely together when addressing IDN TLDs in Punycode

Status: RESOLVED INCOMPLETE

(Core :: Networking: DNS, defect, P3)

Description

[Don Hollander]

User Agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10_11) AppleWebKit/601.1.56 (KHTML, like Gecko) Version/9.0 Safari/601.1.56

Steps to reproduce:

Earlier this year, APNIC Labs ran an experiment to determine if there were any underlying issues preventing the resolution of new Top Level Domains.  The experiment process and results are available http://www.potaroo.net/reports/Universal-Acceptance/UA-Report.pdf






Actual results:

The experiment found an anomaly when IE and Firefox browsers accessed punycode IDN TLDs using Flash.

When the same experiment was run using HTML5, there were no such anomalies.  

Microsoft have been contacted.  I'm using this form to contact Mozilla.  I'm also contacting Adobe for the Flash issue.


Expected results:

There should have been no anomaly.

Comment 1

[Patrick McManus [:mcmanus]]

Hi Don - I appreciate the attachment, but can you please fill out the bug report with what inputs and behaviors were observed vs what was expected (and how other browsers performed). thanks.

Comment 2

[Valentin Gosu [:valentin] (he/him)]

Based on the conclusion of the report, I take it that there's an issue in Flash's punycode handling.
It would be interesting to see if Shumway could be used successfully instead of Flash, but I don't think there's anything else to be done on the Gecko side.

Comment 3

[Don Hollander]

Thanks for looking at this.

If I hear back from Adobe I will let you know the results of that discussion.

I found it interesting that it only happened in two browsers.

Don

Comment 4

[Simon Montagu :smontagu]

There's a suggestion in UA-Report.pdf linked in comment 0 which I think is very likely:

"a possible explanation is that while the script being executed within the browser
resolves the DNS name and performs a web fetch of the object, the script does not appear to recognize the Web object as the requested object within certain browsers.Web object as the requested object within certain browsers. This may be due to the internal framework of the Flash engine in some browsers performing a translation of the Punycode-encoded name into its Unicode equivalent, and then failing to recognize the returned named object as being the originally requested object due to the internal name translation."

It may also be due to the browser itself translating the Punycode-encoded name into its Unicode equivalent where Chrome does not -- you could possibly test this theory in Firefox by running the test with network.IDN_show_punycode set to true in about:config.

This may also be related to bug 309671 (and see also bug 387921).

Comment 5

[Firefox Bug Husbandry Bot]

Bulk change to priority: https://bugzilla.mozilla.org/show_bug.cgi?id=1399258

Comment 6

[Firefox Bug Husbandry Bot]

Bulk change to priority: https://bugzilla.mozilla.org/show_bug.cgi?id=1399258

Comment 7

[u597032]

Flash is no longer supported