Re: SSL renegotiation

So I committed this patch without backpatching anything.  There was some
discussion about the exact strategy for backpatching the behavior
change, but no final agreement; the suggestions were

0. Backpatch as an ERROR.  If it causes failures, people is supposed to
change their apps or something.

1. Don't backpatch the ERROR bit at all, so that if the renegotiation
fails we would silently continue just as currently

2. Do spit the message, but only as a WARNING.  Thinks this may end up
causing log disks to fill up.

3. Add it as an ERROR, but make it possible to disable it, presumably
via a new GUC.  So people can see their security problems and hopefuly
fix them, but if they don't, then they can shut it up via server
configuration.  This would entail a GUC variable that exists in existing
branches but not HEAD (we could avoid an upgradability problem of
postgresql.conf files by having a no-op phantom GUC variable in HEAD).

I was reminded of this once more because I just saw a spurious
renegotiation failure in somebody's production setup.  Kind of like a
recurring nightmare which I thought I had already erradicated.

Opinions?  Also, should we wait longer for the new renegotiation code to
be more battle-tested?

-- 
Álvaro Herrera                http://www.2ndQuadrant.com/
PostgreSQL Development, 24x7 Support, Training & Services