DKIM timeout -
How many seconds to wait for a DKIM query to complete, before scanning continues without the DKIM result. A numeric value is optionally suffixed by a time unit (s, m, h, d, w, indicating seconds (default), minutes, hours, days, weeks).
Whitelist from DKIM -
Works similarly to
whitelist_from, except that in addition to matching an author address (From) to the pattern in the
first parameter, the message must also carry a Domain Keys Identified Mail (DKIM) signature made by a signing domain
(SDID, i.e. the d= tag) that is acceptable to us. Only one whitelist entry is allowed per line, as in
whitelist_from_rcvd. Multiple whitelist_from_dkim lines are allowed. File-glob style characters are allowed for the From
address (the first parameter), just like with whitelist_from_rcvd. The second parameter does not accept wildcards. If
no signing-domain parameter is specified, the only acceptable signature will be an Author Domain Signature (sometimes
called first-party signature) which is a signature where the signing domain (SDID) of a signature matches the domain of
the authors address (i.e. the address in a From header field). Since this whitelist requires a DKIM check to be made,
network tests must be enabled.