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CRLF is obsolete and should be abolished

(fossil-scm.org)
422 points km | 1 comments | 13 Oct 24 19:16 UTC | HN request time: 0.229s | source
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michaelmior ◴[13 Oct 24 20:03 UTC] No.41831072[source]▶
> various protocols (HTTP, SMTP, CSV) still "require" CRLF at the end of each line

What would be the benefit to updating legacy protocols to just use NL? You save a handful of bits at the expense of a lot of potential bugs. HTTP/1(.1) is mostly replaced by HTTP/2 and later by now anyway.

Sure, it makes sense not to require CRLF with any new protocols, but it doesn't seem worth updating legacy things.

> Even if an established protocol (HTTP, SMTP, CSV, FTP) technically requires CRLF as a line ending, do not comply.

I'm hoping this is satire. Why intentionally introduce potential bugs for the sake of making a point?

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amluto ◴[13 Oct 24 20:36 UTC] No.41831364[source]▶
> I'm hoping this is satire. Why intentionally introduce potential bugs for the sake of making a point?

It’s worse than satire. Postel’s Law is definitively wrong, at least in the context of network protocols, and delimiters, especially, MUST be precise. See, for example:

https://www.postfix.org/smtp-smuggling.html

Send exactly what the spec requires, and parse exactly as the spec requires. Do not accept garbage. And LF, where CRLF is specified, is garbage.

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tptacek ◴[13 Oct 24 20:38 UTC] No.41831386[source]▶
If two systems agree, independent of any specification someone somewhere else wrote, to accept a bare NL where a CRLF is specified, that is not "garbage". Standards documents are not laws; the horse drags the cart.
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perching_aix ◴[13 Oct 24 20:56 UTC] No.41831513[source]▶
Laws are also just some ink on paper (and are routinely overruled, circumvented or unenforced in certain jurisdictions), so using this kind of logic in order to encourage standard violations is unsound.

There is a method to this madness, and that's revising the standards.

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tptacek ◴[13 Oct 24 21:09 UTC] No.41831619[source]▶
What's a "standard violation"? The original history of the IETF is a rejection of exactly this mode of thinking about the inviolability of standards, which was the ethos of the OSI.
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1. nsnshsuejeb ◴[13 Oct 24 21:39 UTC] No.41831874[source]▶
Elephant in the room is the trillions of actual servers and user agents that would need to be tested and patched if you retroactively change a standard. Luckily there are some digits after HTTP that allow the concept of new versions of the standard.