Skip to content
New issue

Have a question about this project? Sign up for a free GitHub account to open an issue and contact its maintainers and the community.

Sign up for GitHub

By clicking “Sign up for GitHub”, you agree to our terms of service and privacy statement. We’ll occasionally send you account related emails.

Already on GitHub? Sign in to your account

Jump to bottom

ECDSA: Use unchecked arithmetic for the tryRecover function #4301

Merged
merged 2 commits into from
Jun 8, 2023
Merged

ECDSA: Use unchecked arithmetic for the tryRecover function #4301

Show file tree
Hide file tree
Changes from all commits
Commits
Show all changes
2 commits
Select commit Hold shift + click to select a range
1aa24a1
Use unchecked arithmetic for the ryRecover function
pcaversaccio Jun 2, 2023
08b10b7
Add changeset
pcaversaccio Jun 2, 2023
File filter

Filter by extension

Filter by extension
Conversations
Failed to load comments.
Loading
Jump to
Jump to file
Failed to load files.
Loading
Diff view
Diff view
5 changes: 5 additions & 0 deletions .changeset/four-adults-knock.md
View file
Open in desktop
Original file line number Diff line number Diff line change
@@ -0,0 +1,5 @@
---
'openzeppelin-solidity': patch
---

`ECDSA`: Use unchecked arithmetic for the `tryRecover` function that receives the `r` and `vs` short-signature fields separately.
9 changes: 6 additions & 3 deletions contracts/utils/cryptography/ECDSA.sol
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -98,9 +98,12 @@ library ECDSA {
* _Available since v4.3._
*/
function tryRecover(bytes32 hash, bytes32 r, bytes32 vs) internal pure returns (address, RecoverError) {
bytes32 s = vs & bytes32(0x7fffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffff);
uint8 v = uint8((uint256(vs) >> 255) + 27);
return tryRecover(hash, v, r, s);
unchecked {
bytes32 s = vs & bytes32(0x7fffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffff);
pcaversaccio marked this conversation as resolved.
Show resolved Hide resolved
// We do not check for an overflow here since the shift operation results in 0 or 1.
uint8 v = uint8((uint256(vs) >> 255) + 27);
return tryRecover(hash, v, r, s);
}
}

/**
Expand Down