Re: [TLS] Narrowing allowed characters in ALPN ?

"Salz, Rich" <rsalz@akamai.com> Thu, 20 May 2021 13:30 UTC

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From: "Salz, Rich" <rsalz@akamai.com>
To: Martin Thomson <mt@lowentropy.net>, "tls@ietf.org" <tls@ietf.org>
Thread-Topic: [TLS] Narrowing allowed characters in ALPN ?
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Date: Thu, 20 May 2021 13:30:09 +0000
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Subject: Re: [TLS] Narrowing allowed characters in ALPN ?
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Look at RFC 701, it says: the precise set of octet values that identifies the protocol. This could be the UTF-8 encoding of the protocol name.

So I changed my mind and think it's okay to leave as-is but wouldn't mind if it became less general or more specific. For example, what if a protocol string matches a truncated UTF8 string?  It makes me think of SNI which could have any format, but really is "any format as long as it's a DNS name"