revision 3: easing access to the cryptographic envelope

[David Bremner]

Daniel Kahn Gillmor <dkg at fifthhorseman.net> writes:

> This is the third revision of the series originally posted at
> id:20190424183113.29242-1-dkg at fifthhorseman.net (revision 2 was at
> id:20190520032228.27420-1-dkg at fifthhorseman.net)
>
> This series addresses comments raised by David Bremner in his review.
> Thanks, Bremner!

I pushed this version, with 4 minor whitespace fixups (inserted spaces
and/or deleted blank lines) that I missed in my previous review.

d