binary content, non-paddability

[bsdphk]

I'm not sure I understand the ban on '=' in binary content, how can that confuse dictionaries, when the binary content doesn't end until the final '*' ?

[mnot]

It's from when there wasn't a final delimiter. I think you're right; we should accept =. I think we should also accept without.

[bsdphk]

I think we should just rely on whatever the B64 rfc says, without inventing anything new. (Postel Was Wrong and all that.)

[mnot]

It says:

Implementations MUST include appropriate pad characters at the end of encoded data unless the specification referring to this document explicitly states otherwise.

I think we want to make it easy to conform to whatever we require with shipping implementations of base64. Spot-checking Python and Node, it seems like Python enforces the requirement, whereas Node does not.

Given that, it seems like the sensible thing to do is to require the padding to be produced with a MUST, but only require parsers to reject content without padding as a SHOULD.

See also #473.

[bsdphk]

WFM