1565022 - TRR: Check for NRPT on Windows to use platform DNS

Status: VERIFIED FIXED

(Core :: Networking: DNS, enhancement, P1)

Description

[Andy Grover [:grover]]

Attachment: example reg key

We have received information that app-based DNS should not be used in some cases, for example when NRPT (Name Resolution Policy Table) is in use.

If any keys exist under the following paths…

• HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\Dnscache\Parameters\DnsPolicyConfig
• HKEY_LOCAL_MACHINE\SOFTWARE\Policies\Microsoft\Windows NT\DNSClient\DnsPolicyConfig

THEN YOU…

MUST USE platform DNS at least for domain names matching these keys

• Check the “Name” value of the key for matching domain pattern
  • See example reg key structure below with optional fields such as DNSSEC configuration omitted
  • In the example reg key, the “Name” value is “*.example.com”
• Easier implementation: defer to platform DNS if any NRPT rules exist

MAY USE app DNS for domain names that don’t match any keys

• Single labels match as prefixes (ex: “example” matches “example.com”)
• Multiple labels match as suffixes (ex: “example.com” matches “foo.bar.example.com”)
• “.” Matches all domain names

Comment 1

[Andy Grover [:grover]]

If we did this then bug 1083569 might also become easier.

Comment 2

[Honza Bambas (:mayhemer)]

Taking and making P1 (for 71 cycle) at Nhi's request.

Comment 3

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

Attachment: Bug 1565022 - TRR: Check for NRPT on Windows to use platform DNS r=mayhemer

Depends on D54092

Comment 4

[Pulsebot]

Pushed by [e-mail]:
https://hg.mozilla.org/integration/autoland/rev/074d4ac319da
TRR: Check for NRPT on Windows to use platform DNS r=mayhemer

Comment 5

[Andrei Ciure[:aciure]]

https://hg.mozilla.org/mozilla-central/rev/074d4ac319da

Comment 6

[Emil Ghitta, QA [:emilghitta]]

This has been covered as part of our testing efforts for PI-335 on Fx 72.

I'm marking this bug as verified fixed since no new issues were encountered during our test runs and exploratory testing sessions.