Milter.dev
The Milter Protocol
Connection & Socket
Callback Sequence
Return Values
smfi_* Functions
Sendmail vs Postfix
Implementations
Auth & Signing
Antispam
Antivirus
Policy & Greylisting
Frameworks
Auth & Signing
OpenDKIM (DKIM1)
DarkChain (DKIM2)
OpenARC
DarkARC
OpenDMARC
smf-spf (SPF)
DKIM2 via Milter
Overview
DarkGlobe Suite
IETF Draft & WG
WG Status
Blog
Auth & Signing
Milters implementing email authentication protocols: DKIM, ARC, SPF.