[TLS] TLS ALPN (rfc7301), no reserved seperator char and why is 0 no banned

mrex@sap.com (Martin Rex) Mon, 13 April 2015 21:18 UTC

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Date: Mon, 13 Apr 2015 23:18:11 +0200 (CEST)
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From: mrex@sap.com (Martin Rex)
Archived-At: <http://mailarchive.ietf.org/arch/msg/tls/li9b8KoXswrqPs27ASZsFQHgUNk>
Subject: [TLS] TLS ALPN (rfc7301), no reserved seperator char and why is 0 no banned
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I have only recently looked at the TLS extension ALPN spec (RFC7301)
and it seems that there currently is no reserved character for the
ALPN ID registry that could be used as seperator character if one
wanted to facilitate the admin/user UI and tracing/logging.

While I don't allowing UTF8, I would have really appreciated
reserving at least one character (or octet value) for the obvious
purpose of printing all currently offered protocols in a single line.

I'm also puzzled why the octet value 0 was not banned from the
ALPN ID either.  That seems like calling for trouble.

-Martin