MID module
The purpose of the MID module is to suppress the INVALID_MSGID (malformed Message-ID header) and MISSING_MID (missing Message-ID) rules for messages which are DKIM-signed by some particular domains.
Configuration
The module requires a source parameter pointing to a map file.
Configuration options
| Option | Default | Description |
|---|---|---|
source | required | Map of domains and optional Message-ID patterns |
symbol_known_mid | KNOWN_MID | Symbol for known Message-ID pattern match |
symbol_known_no_mid | KNOWN_NO_MID | Symbol for known missing Message-ID |
symbol_invalid_msgid | INVALID_MSGID | Symbol to suppress for invalid Message-ID |
symbol_missing_mid | MISSING_MID | Symbol to suppress for missing Message-ID |
symbol_dkim_allow | R_DKIM_ALLOW | DKIM allow symbol to check |
csymbol_invalid_msgid_allowed | INVALID_MSGID_ALLOWED | Composite symbol for allowed invalid Message-ID |
csymbol_missing_mid_allowed | MISSING_MID_ALLOWED | Composite symbol for allowed missing Message-ID |
Example configuration
mid = {
source = "${CONFDIR}/mid.inc";
}
The source setting points to a map to check DKIM signatures (& optionally message-ids) against, formatted as follows:
example.com /^[a-f0-9]{8}(?:-[a-f0-9]{4}){3}-[a-f0-9]{12}-0$/
example.net
With this configuration scoring for INVALID_MSGID and MISSING_MID symbols is removed if the domain is DKIM-signed example.net or the domain is signed example.com and the message-id matches the specified regex.