LLT-7632: Use private key from requested state to configure DERP - #1982
Open
tomaszpatejko wants to merge 1 commit into
Open
LLT-7632: Use private key from requested state to configure DERP#1982tomaszpatejko wants to merge 1 commit into
tomaszpatejko wants to merge 1 commit into
Conversation
If a DERP peer sets a secret key on its WG interface incorrectly (due to, for example, error returned by WG interface), other DERP peers, will not be able to identify this peer with a public key derived from its private key. This will happen because DERP relay receives the incorrect secret key in the DERP config and uses this key to establish direct connection between peers. So a secret key from requested state is used to configure DERP. This key in turn is used for WG interface reconfiguration in consolidate_wg_state function. Fixes LLT-7632.
tomaszpatejko
force-pushed
the
LLT-7632-relay-cant-authenticate-with-garbage-key
branch
from
September 8, 2026 12:23
a1e9a1c to
be47af3
Compare
This file contains hidden or bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
Sign up for free
to join this conversation on GitHub.
Already have an account?
Sign in to comment
1 participant
Add this suggestion to a batch that can be applied as a single commit.This suggestion is invalid because no changes were made to the code.Suggestions cannot be applied while the pull request is closed.Suggestions cannot be applied while viewing a subset of changes.Only one suggestion per line can be applied in a batch.Add this suggestion to a batch that can be applied as a single commit.Applying suggestions on deleted lines is not supported.You must change the existing code in this line in order to create a valid suggestion.Outdated suggestions cannot be applied.This suggestion has been applied or marked resolved.Suggestions cannot be applied from pending reviews.Suggestions cannot be applied on multi-line comments.Suggestions cannot be applied while the pull request is queued to merge.Suggestion cannot be applied right now. Please check back later.
Problem
If a DERP peer sets a secret key on its WG interface incorrectly (due to, for example, error returned by WG interface), other DERP peers, will not be able to identify this peer with a public key derived from its secret key.
This happens because DERP relay receives the incorrect secret key in the DERP config and uses this key to establish direct connection between peers.
Solution
A secret key from
RequestedState::device_configis used to configure DERP. This key in turn is used for WG interface reconfiguration inconsolidate_wg_statefunction.Fixes LLT-7632.
☑️ Definition of Done checklist