.onion request in regular window should also avoid DNS leakage

[diracdeltas]

#13527 fixed the issue of .onion leaking DNS in Tor windows, but the issue should also be fixed in regular windows because users may accidentally enter a .onion in a regular window instead of a Tor window. this happens regardless of whether the 'Automatically redirect .onion' option is selected.

STR:

1. disable DoH (makes it easier to see requests in wireshark)
2. open wireshark and filter by DNS
3. open a regular tab and navigate to facebookcorewwwi.onion
4. you see DNS requests in wireshark

expected behavior: brave should block DNS if it sees a top-level navigation to a .onion URL both when the 'Automatically redirect .onion' is on and when it is off.

[fmarier]

For reference, this is mentioned in RFC7686.

Here's Firefox test case for it: https://searchfox.org/mozilla-central/source/netwerk/test/unit/test_dns_onion.js

[GeetaSarvadnya]

Verification passed on

Brave | 1.20.110 Chromium: 88.0.4324.192 (Official Build) (64-bit)
-- | --
Revision | 31b458a18f133db9203eb5a5dd6552de0716dda3-refs/branch-heads/4324_182@{#6}
OS | Windows 10 OS Version 2004 (Build 19041.804)

Verified the test plan from https://github.com/brave/brave-core/pull/8040#issue-578027432

Auto redirect off

• Confirmed that visiting https://brave5t5rjjg3s6k.onion/ in a normal window gave an error page and the .onion URL did not result in a DNS lookup in Wireshark.
  

• Clicked on the "Open in Tor" button in above window. Confirmed https://brave5t5rjjg3s6k.onion/ was opened in a Tor window.
  

• Went to tab from step 2 and entered https://brave5t5rjjg3s6k.com. Confirmed no "Open in Tor" button.
  

Auto redirect on

Confirmed visiting https://brave5t5rjjg3s6k.onion/ in a normal window with "Automatically redirect .onion sites" on showed an error page on normal window and opened a Tor window with the site. Confirmed no DNS lookup in Wireshark.

Verified the test plan from https://github.com/brave/brave-core/pull/7713#issue-562159331

• Ensured Automatically redirect .onion sites is enabled in brave://settings/extensions
  

• Verified only one tab opened which is https://brave5t5rjjg3s6k.onion and no new tab in a Tor window
  

• Confirmed there were still only two Tor tabs, https://brave5t5rjjg3s6k.onion and http://expyuzz4wqqyqhjn.onion/index.html
  

---

Verified passed with

Brave	1.20.110 Chromium: 88.0.4324.192 (Official Build) (x86_64)
Revision	31b458a18f133db9203eb5a5dd6552de0716dda3-refs/branch-heads/4324_182@{#6}
OS	macOS Version 10.15.7 (Build 19H512)

Reproduced issue using STR from description with 1.20.108. Confirmed DNS lookup was observed in Wireshark.

Verified test plan from brave/brave-core#8040 using 1.20.110:

Auto Redirect Off

Confirmed that visiting https://brave5t5rjjg3s6k.onion/ in a normal window gave an error page and the .onion URL did not result in a DNS lookup in Wireshark.

Clicked on the "Open in Tor" button in above window. Confirmed https://brave5t5rjjg3s6k.onion/ was opened in a Tor window.

Went to tab from step 2 and entered https://brave5t5rjjg3s6k.com. Confirmed no "Open in Tor" button.

Auto Redirect On

Confirmed visiting https://brave5t5rjjg3s6k.onion/ in a normal window with "Automatically redirect .onion sites" on showed an error page on normal window and opened a Tor window with the site. Confirmed no DNS lookup in Wireshark.

---

Verification passed on

Brave	1.20.110 Chromium: 88.0.4324.192 (Official Build) (64-bit)
Revision	31b458a18f133db9203eb5a5dd6552de0716dda3-refs/branch-heads/4324_182@{#6}
OS	Ubuntu 18.04 LTS

Verified test plan from brave/brave-core#8040

Reproduced the issue on 1.20.108

Auto Redirect Off

Verified an error page is shown and that the .onion didn't result in a DNS lookup.

Verified the page is opened in Tor Window after clicking "Open in Tor" button

Verified openning https://brave5t5rjjg3s6k.com/ clears "Open in Tor" button

Auto Redirect On

Confirmed visiting https://brave5t5rjjg3s6k.onion/ in a normal window with "Automatically redirect .onion sites" on showed an error page on normal window and opened a Tor window with the site. Confirmed no DNS lookup in Wireshark.

Verified FIXED using brave/brave-core#8040 (comment) and brave/brave-core#7713 (comment)

Brave	1.20.110 Chromium: 88.0.4324.192 (Official Build) (x86_64)
Revision	31b458a18f133db9203eb5a5dd6552de0716dda3-refs/branch-heads/4324_182@{#6}
OS	macOS Version 11.2.1 (Build 20D74)

Brave	1.20.110 Chromium: 88.0.4324.192 (Official Build) (64-bit)
Revision	31b458a18f133db9203eb5a5dd6552de0716dda3-refs/branch-heads/4324_182@{#6}
OS	Windows 10 OS Version 2009 (Build 21318.1000)

Auto redirect off

• Started Wireshark and filtered for dns.
• disabled DoH in brave://settings/security (makes it easier to see requests in Wireshark)
• Opened a normal window and typed https://brave5t5rjjg3s6k.onion/ in the URL bar.
• Confirmed I got an error page and that the .onion didn't result in a DNS lookup.

screenshot

• Verified there was an "Open in Tor" button
• Clicked it and confirmed that it opened https://brave5t5rjjg3s6k.onion/ in Tor window
• Went back to the tab of step 2 and typed https://brave5t5rjjg3s6k.com/ in the URL bar.
  Verified no "Open in Tor" button.

screenshot

Auto redirect on

• Started Wireshark and filtered for dns.
• disable DoH in brave://settings/security (makes it easier to see requests in Wireshark)
• Went to brave://settings/extensions and turned on Automatically redirect .onion sites
• Opened a normal window and typed https://brave5t5rjjg3s6k.onion/ in the URL bar.
• Confirmed that I got an error page and that the .onion didn't result in a DNS lookup.
• Confirmed that Tor window opened automatically with https://brave5t5rjjg3s6k.onion/

screenshot

From brave/brave-core#7713:

Verified we only have single Tor tabs, and that we didn't close the .com tab, for both https://brave5t5rjjg3s6k.onion and http://expyuzz4wqqyqhjn.onion/index.html

screenshot