DMARC protection: "p" tag is not applied to subdomains

[ikedas]

Version

6.2.43b.2 or earlier.

Installation method

Any.

Expected behavior

If a domain example.org has these DNS RRs:

_dmarc.example.org.      IN TXT "v=DMARC1; p=reject"
_dmarc.sub.example.org.  IN TXT "v=DMARC1; p=quarantine"

mail receiver should interpret them as:

• reject policy is applied to user@example.org.
• quarantine policy is applied to user@sub.example.org.
• reject policy is applied to other subdomains e.g. user@other.example.org.

And, sp tag should be supported along with p tag (See also RFC7489).

Actual behavior

Sympa's DMARC protection behaves as:

• dmarc_reject option matches against user@example.org.
• dmarc_quarantine option matches against user@sub.example.org.
• However, neither of options above matches against othter subdomains e.g. user@other.example.org.

And, sp tag is never recognized.