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daksh_s

Member

Registered: Today

Posts: 3

[PROFILE] "Invalid URL" on a perfectly valid URL because of underscore

okay so apparently because of the underscore, this is an invalid URL:-

https://daksh_s.codeberg.page

when in-fact, it is perfectly correct? (and no it's not because of the missing w3 prefix because somehow codeberg pages doesn't work with the w3 prefix lmao, atleast mine shows an SSL error)

I understand that this may be a security feature or system limitation on the server side but I hope it can be fixed.

mpan

Member

Registered: 2012-08-01

Posts: 1,553

Website

Re: [PROFILE] "Invalid URL" on a perfectly valid URL because of underscore

It’s neither a security feature nor system limitation.

An underscore is not among characters that may be in a hostname. These are ASCII letters, digits, and a hyphen.

If that address resolves for you, it’s by pure coincidence. DNS servers do not waste resources on actively validating RRs. Since labels may in general contain any octet, the invalid A and AAAA records slip through; to a DNS server they’re just another opaque data passed around for some label.

It’s not even a bug on Codeberg’s end, beause it’s not a record intentionally disseminated by them. The DNS has a wildcard that resolves any name to their host. It will accept these two too:

a-totally-non-existent-username-dxywgy3m.codeberg.page
even*clearly^invalid%names.codeberg.page

Last edited by mpan (Today 03:33:44)

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