Reject zero inputs in bls_modular_inverse() #3299
Merged
Conversation
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
Contributor
Author
|
I will add a unittest for this tomorrow as well. |
asn-d6
force-pushed
the
inv_no_inputs
branch
3 times, most recently
from
77443a2 to
f8bd0cf
Compare
Member
|
LGTM! |
haxxpop
approved these changes
Mar 17, 2023
dankrad
approved these changes
Mar 17, 2023
Sign up for free
to join this conversation on GitHub.
Already have an account?
Sign in to comment
4 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Outdated suggestions cannot be applied.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.
Zero doesn't have a multiplicative inverse and having bls_modular_inverse() return zero upon receiving zero was a convention.
We then noticed that implementing that convention in blst was not straightforward, so we decided to revisit it.
Given that there is no point in the spec where bls_modular_inverse() is called with zero as its input, and given that from a protocol point of view that convention doesn't make much sense, we decided to instead reject zero as inputs to bls_modular_inverse(). This PR makes it so.