DKIM verification The project was started as a fork of https://github.com/kalloc/dkim Original plan was just fix few defects and create PR but eventually the project was totally overhauled. TODO Copied header fields (z=) verification RFCs RFC6376 DomainKeys Identified Mail (DKIM) Signatures RFC4686 Analysis of Threats Motivating DomainKeys Identified Mail (DKIM) RFC5863 DomainKeys Identified Mail (DKIM) Development, Deployment, and Operations RFC7601 Message Header Field for Indicating Message Authentication Status