Auto-port 5.0: Remove note about needing 256-bit for PQC#16614
Merged
Conversation
(cherry picked from commit f31e5ae)
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
2 participants
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Outdated suggestions cannot be applied.This suggestion has been applied or marked resolved.Suggestions cannot be applied from pending reviews.Suggestions cannot be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.
Auto-port of #16605 to 5.0
Cherry-picked commit: f31e5ae
Motivation:
In the test for hybrid-post-quantum key agreement, we had a comment that 128-bit symmetric ciphers should also be disabled to be quantum safe.
The general consensus among cryptographers is now that this is an unnecessary overreaction, and that 128-bit symmetric ciphers are perfectly fine and safe against cryptographically relevant quantum computers.
The reason is that Grover's algorithm (the main threat to symmetric ciphers) is not parallelizable, hasn't seen any significant optimizations (rather, proofs have been created showing that it is optimal), and is on its own not enough to make any meaningful dent in the security of symmetric ciphers.
See for instance Filipo Valsoda's April 6, 2026 blog post: https://words.filippo.io/crqc-timeline/
Another reason for removing the configuration of ciphers is that BoringSSL actually ignores the configured cipher suite. So when using BoringSSL the ciphers weren't actually disabled anyway.
Modification:
Remove the configuration of ciphers from the
connectWithX25519MLKEM768test.Result:
More realistic looking test, based on our most recent knowledge of PQC.