swift-crypto Fix over-iterating buffer in hex string utility.

Fix over-iterating buffer in hex string utility.

Open VaslD opened this issue 2 years ago • 7 comments

Fixes https://github.com/apple/swift-crypto/issues/139: over-iteration in hex string.

Checklist

[x] I've run tests to see all new and existing tests pass
[x] I've followed the code style of the rest of the project
[x] I've read the Contribution Guidelines
[x] I've updated the documentation if necessary

If you've made changes to `gyb` files

[x] I've run .script/generate_boilerplate_files_with_gyb and included updated generated files in a commit of this pull request

Motivation:

Upon discussing it in https://github.com/apple/swift-crypto/issues/139, an issue was identified that could cause unexpected hex output for a data buffer whose memory spans multiple non-contiguous regions.

Modifications:

Removed memory region specific logic. Fix applied to 3 copies of the same function.

Also added unit test on Apple platforms to compare with NSString's hex output.