message-signatures: ASCII restriction in field-value to byte sequence

[reschke]

in 2.1.3:

Encode the bytes of the resulting field value's ASCII representation as a Byte Sequence.

What if the field value contains non-ASCII characters (from obs-text)?

Of course that could be considered an error, but I believe the intention is to be able to represent anything here. So the text should refer to the field value as byte sequence, in which case the encoding step would not be needed.

[jricher]

This text was added in response to a comment about needing to know which encoding to put into the byte sequence input, and the commenter suggested ASCII as the base for it. If field values have a well-defined byte sequence that isn't ASCII characters only, then we should refer to whatever that is from the HTTP docs.

[reschke]

Well, field values in HTTP can be anything. It's obsolete, it's deprecated, but that's what it is. So we need to deal with it one way or another.

I could live with UTF-8, and a note that if the octet sequence does not decode as UTF-8, you can't sign it.

[reschke]

@jricher - yes, you can merge and close issues as you wish, you are the editor. But by all means do not submit a new draft until the changes have been reviewed by those who opened the issue. (cc chairs @mnot @tfpauly )

[reschke]

As far as I can tell, the changes require percent-encoding only for non-ASCII values. That is, the character U+0080 would get the same encoding as a verbatim "%80" in a field value. I believe this is a problem.

[jricher]

This issue has been addressed. There is no percent encoding needed in this section since the value is taken directly from the bytes of the field in a binary-wrapped representation, and the bytes are encoded using the base64 serialization of a Byte Sequence from Structured Fields:

Encode the bytes of the resulting field value as a Byte Sequence. Note that most fields are restricted to ASCII characters, but other octets could be included in the value in some implementations.

[reschke]

I'm talking about the simple case, not the one where Byte Sequence encoding is used (yes, the issue title doesn't match anymore).

[reschke]

Ok, opened new issue #2513