# std.crypto.edwards25519: add a rejectLowOrder\(\) function \(\#13668\) · gitcafe/zig

[View on GitCafe](https://git.cafe/gitcafe/zig/commit/7411be3c9e6d169108456f03b3cbb9b476ee7498)

Repository: [gitcafe/zig](https://git.cafe/gitcafe/zig)

Visibility: public

Requested revision: 7411be3c9e6d169108456f03b3cbb9b476ee7498

Requested commit: 7411be3c9e6d169108456f03b3cbb9b476ee7498

Commit: 7411be3c9e6d169108456f03b3cbb9b476ee7498

Tree: ac2d936d1236034cc4a274a493bed1ded0bc05b4

Author: Frank Denis

Committer: GitHub

## Message

```
std.crypto.edwards25519: add a rejectLowOrder() function (#13668)

Does what the name says: rejects generators of low-order groups.

`clearCofactor()` was previously used to do it, but for e.g.
cofactored signature verification, we don't need the result of an
actual multiplication. Only check that we didn't end up with a
low-order point, which is a faster operation.
```

## Parents

- [609716524169c538b7f12666c3f9bb46a0aeeb3c](https://git.cafe/gitcafe/zig/commit/609716524169c538b7f12666c3f9bb46a0aeeb3c?format=markdown)

[Source at this commit](https://git.cafe/gitcafe/zig/tree/7411be3c9e6d169108456f03b3cbb9b476ee7498?format=markdown)