1228578 - Change to security model prevents proxies to inform users when they refuse to forward connections

Status: RESOLVED DUPLICATE of bug 493699

(Core :: Networking: HTTP, defect)

Description

[Thomas Mangin]

User Agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10_11_1) AppleWebKit/601.2.7 (KHTML, like Gecko) Version/9.0.1 Safari/601.2.7

Steps to reproduce:

We are asking our customer to configure an HTTP/HTTPS proxies to surf the web. For policy reason the connection can be refused ( for example kids attempting to access pornographic content ). With HTTPS, the browser get a CONNECT command which includes the name of the remote host. A few months (years) back, browsers where able to return a 302 message (or 403/450) and have the browser display a page explaining the reason for refusing the connection, the is no the case anymore.


Actual results:

Currently the only thing the proxy can do is to close the TCP connection with the client which presents the "unable to connect" page which is not user friendly.


Expected results:

The proxy should be able to ask the browser to display some form of message. It could be a fixed page ( access denied ) or let the proxy return some other page / content to the browser.

As clearly, the end-user should not be tricked in thinking they are on the expected site, some form of large warning could be associated with any dynamic page displayed.

For security reason, this feature could also be a disabled by default.

This problem was also discussed on the chromium list:
https://groups.google.com/a/chromium.org/forum/#!topic/chromium-bugs/Pj7AP4fF6a4
https://code.google.com/p/chromium/issues/detail?id=125457

Comment 1

[Gingerbread Man]

Also see bug 637619.