[squid-dev] Support lower case http/ spn format for realmd/adcli join support.

[Amos Jeffries]

On 28/06/18 08:24, Mike Surcouf wrote:
> Thanks Amos for your comprehensive reply..  open SSH requires lower case
> host/ and as you say windows doesn't seem to care so they solved it for
> that case but seems that uppercase is the convention for HTTP.
>   Do you have an official reference for HTTP/. As the official uppercase
> format of SPN for http protocol.i will then file a bug on the adcli repo.
> 


If I'm understanding the descriptions right it is
<https://tools.ietf.org/html/rfc4120#section-6.2> .

with the SPN being "realm/principal"

6.1 says realm is case sensitive.

6.2 says principal is case insensitive and syntax may be of several
types, one of those being:

  principal = name '@' host

I am taking an educated guess that since the resulting syntax of those
would look like REALM/SomeName at example.org that is what the SPN string
is based on.



The case of "HTTP" as in transport is RFC 7230. Specifically section 2.6
(<https://tools.ietf.org/html/rfc7230#section-2.6>) where the exact
octets are prescribed:

"
     HTTP-name     = %x48.54.54.50 ; "HTTP", case-sensitive
"

Anything else is non-compliant with HTTP and may contain arbitrary other
errors in both syntax and behaviour - handle at own risk, etc.


Amos