bug#17625: 24.4.50; All installed packages marked "unsigned", no archive listed

[Glenn Morris]

PS I won't pretend to know what I am talking about here, but I worry
that the combination of automated package signing and automated key
installation will make this package-signing feature not worth very much
in practice.

Eg if clients automatically (even with prompting) install public keys
from the package server the first time they connect, then this leaves
zero protection against a man-in-the-middle attack. I connect to
something that says it is elpa.gnu.org and install the key it offers.
I have no way to know if it really is elpa.gnu.org.

(With elpa.gnu.org we should distribute the public key in the Emacs etc/
directory.)