ATTN!  This release may crash unless "report_all_sigs" is set
or database logging is enabled —both of which imply examining
all the signatures of received messages.


Test failure:
=============

The last test in the "make check" suite is doomed to fail unless
libopendkim is upgraded or patched so as to support EAI.


PSDDMARC:
=========

Added support for experimental extension to DMARC.  This is enabled
by setting a new option, psddmarc, to a file like the distributed
tentative-psddmarc-list.txt.  See https://psddmarc.org/.


Database changes:
================
Convert to UTF-8, since domains and email addresses can now be encoded
that way.  SQL commands:

ALTER TABLE domain \
  CONVERT TO CHARACTER SET utf8mb4 COLLATE utf8mb4_general_ci;
ALTER TABLE message_in \
  CONVERT TO CHARACTER SET utf8mb4 COLLATE utf8mb4_general_ci;
ALTER TABLE message_out \
  CONVERT TO CHARACTER SET utf8mb4 COLLATE utf8mb4_general_ci;
ALTER TABLE msg_out_ref \
  CONVERT TO CHARACTER SET utf8mb4 COLLATE utf8mb4_general_ci;
ALTER TABLE msg_ref \
  CONVERT TO CHARACTER SET utf8mb4 COLLATE utf8mb4_general_ci;
ALTER TABLE user \
  CONVERT TO CHARACTER SET utf8mb4 COLLATE utf8mb4_general_ci;

Before running zdkimfilter again, the database can be converted using
a script like db_conv.sh (distributed but not installed).  It calls
2idn, a command inverse of idn2 (distributed and installed).  Then,
domain names will be converted to utf-8 before storing them.


New table dmarc_bounce (see odbx_example.sql).  It is queried via
db_sql_check_dmarc_rcpt before sending aggregate reports.  The .sql
file contains a procedure to insert addresses in there, for use with
the new -1 option of zaggregate (not tested).


Add two 'spamtrap' fields, one in message_in to be turned on by
spamtrap recipes, one in domains which accumulates the former at
end-of-day:

ALTER TABLE message_in \
  ADD COLUMN spamtrap TINYINT NOT NULL DEFAULT 0 AFTER mailing_list;
ALTER TABLE domain \
  ADD COLUMN spamtrap INT UNSIGNED NOT NULL DEFAULT 0 AFTER sent;


In v1.6, db_sql_select_domain was not used, db_sql_insert_msg_ref did
insert/update of domain as well as new msg_ref record.  In v1.7 there
may be multiple msg_ref records.  So, in .conf:

add     db_sql_select_domain (call to reduced recv_from_domain())
change  db_sql_insert_msg_ref (plain insert)

From .sql: re-define stored procedure recv_from_domain(), and

ALTER TABLE msg_ref \
  ADD COLUMN dkim_selector VARCHAR(63) NOT NULL DEFAULT '' AFTER vbr;


Other changes:
==============
zaggregate-example.sh:  add a subdomain, to avoid autosustained report
loops.  Thanks to Juri Haberland for the hint.

zaggregate-cancel-example.sh:  new script for cancelling unsent reports.

urlencode, urldecode, and 2idn: new executable utilities.