On 21 April 2017 at 12:11, John Levine <johnl(_at_)taugh(_dot_)com> wrote:
If a recipient is cooperative, and sends you back a message signed
with the same key to which you encrypted the message, that tells you
he got it, but that's not a very interesting case.
It's also abuse of the cryptographic primitives, I hope that this
isn't really how it works and you are eliding certain key details.