Host header checks and case sensitivity

Mark Thomas <markt@apache.org> Tue, 12 December 2023 14:15 UTC

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From: Mark Thomas <markt@apache.org>
To: ietf-http-wg@w3.org
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Subject: Host header checks and case sensitivity
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Hi all,

A (hopefully) quick question.

In RFC 9112, section it states that:

"If the target URI includes an authority component, then a client MUST 
send a field value for Host that is identical to that authority 
component..."

Given that host is case insensitive, is the intention that "identical" 
in the text above means "identical, ignoring differences in case"?

I can't think of any reason why this particular check needs to be case 
sensitive but wanted to check in case I was missing something.

Thanks,

Mark