Functionality
=============

There needs to be a way to force "smtp_tls_security_level=may"
for rmail deliveries of daily TLSRPT summaries.

Paranoia
=========

Should there be a check that the TLSRPT policy for domain FOO 
has an 'rua' field that contains FOO?

Paranoia: in IPC protocols base64 encode data that is not fully vetted.
TLSRPT_WRAPPER.rpt_policy
TLSRPT_WRAPPER.policy strings
TLSRPT_WRAPPER.ehlo_cmd string.

Code health
===========
Remove the trw_report_failure() additional_info argument. This is
always null.

Need to add a hex_code test for HEX_ENCODE_FLAG_APPEND.

Deduplicate the code in sane_sockaddr_to_hostaddr(). It also appears in
haproxy_srvr.c, normalize_mailhost_addr.c, and in postscreen_endpt.c.

Need unit tests for smtp_tlsrpt.c and tlstrpd_wrapper.c. This
requires infrastructure.
