[DNSOP] alpn parsing in SVCB
Shane Kerr <shane@time-travellers.org> Tue, 19 April 2022 18:16 UTC
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From: Shane Kerr <shane@time-travellers.org>
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Cc: Ben Schwartz <bemasc=40google.com@dmarc.ietf.org>,
Erik Nygren <erik+ietf@nygren.org>
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Subject: [DNSOP] alpn parsing in SVCB
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Dear Colleagues, I know it's really late, but I hadn't worked with the SVCB until recently. Apologies if this has been thoroughly discussed. 😬 I implemented a parser for the "alpn" service parameter, and the code was a lot more complex than I thought it should be. Basically, the double-encoding required for full implementation of the presentation format is cumbersome. I also think it is completely unnecessary. Can't we just restrict alpn, so that we don't use comma in the name? That would get rid of the need for the double-encoded values, the decision that implementers have to make whether or not to support them, plus all of Appendix A. I don't see any strong motivation for allowing comma in alpn name. As far as I can tell none of the existing ALPN values use a comma: https://www.iana.org/assignments/tls-extensiontype-values.xhtml#alpn-protocol-ids Again, apologies for chiming in so late. Maybe other implementers have had a different experience with this, and I'm way off-base. But if others agree, maybe it's not *too* late? Cheers, -- Shane
- [DNSOP] alpn parsing in SVCB Shane Kerr
- Re: [DNSOP] alpn parsing in SVCB Ben Schwartz