HTTP2 spec HEADERS padding needs clarification

Daurnimator <quae@daurnimator.com> Mon, 16 March 2015 19:02 UTC

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Date: Mon, 16 Mar 2015 14:57:49 -0400
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Subject: HTTP2 spec HEADERS padding needs clarification
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>From 6.2 HEADERS:
> The HEADERS frame can include padding. Padding fields and flags are identical to
> those defined for DATA frames (Section 6.1).

>From 6.1 DATA:
> The total number of padding octets is determined by the value of the Pad Length field.
> If the length of the padding is the length of the frame payload or greater, the recipient
> MUST treat this as a connection error (Section 5.4.1) of type PROTOCOL_ERROR.

This could do with clarification. The HEADERS frame has additional
fields around priority.
i.e. stream dependency, weight.

I assume it should be a protocol error if padding length does not
leave enough room for weight?
Or could it be a valid frame for an empty header fragment and a weight
of 0 that overlaps padding?

Daurn.