feat: fix v computation in ECDSA signature #385
Merged
Conversation
This file contains 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
p4u
pushed a commit
to vocdoni/gnark-crypto
that referenced
this pull request
May 4, 2023
* fix: first ecdsa v bit is oddity * fix: recover oddity of public key y * chore: generate * fix: add check for s * chore: generate
Sign up for free
to join this conversation on GitHub.
Already have an account?
Sign in to comment
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Outdated suggestions cannot be applied.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.
I referred to other implementations to understand how v is computed when creating an ECDSA signature. I had assumed that v gives if
ycoordinate of the ephemeral point is small or large (e.h. bigger than half the order). But due to different encoding order, it was actually the oddity ofy.This is confirmed also in Ethereum Yellow paper (Appendix F) and makes also a lot more sense.