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michaelmior ◴[] 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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FiloSottile ◴[] No.41831391[source]
Exactly. Please DO NOT mess with protocols, especially legacy critical protocols based on in-band signaling.

HTTP/1.1 was regrettably but irreversibly designed with security-critical parser alignment requirements. If two implementations disagree on whether `A:B\nC:D` contains a value for C, you can build a request smuggling gadget, leading to significant attacks. We live in a post-Postel world, only ever generate and accept CRLF in protocols that specify it, however legacy and nonsensical it might be.

(I am a massive, massive SQLite fan, but this is giving me pause about using other software by the same author, at least when networks are involved.)

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tptacek ◴[] No.41831450[source]
This would be more persuasive if HTTP servers didn't already widely accept bare 0ah line termination. What's the first major public web site you can find that doesn't?
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michaelmior ◴[] No.41831506[source]
We're talking about servers and clients here. The best way to ensure things work is to adhere to an established protocol. Aside from saving a few bytes, there doesn't seem to be any good reason to deviate.
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1. Ekaros ◴[] No.41831637[source]
There is very good reasons not to deviate as mismatch in various other things that can or are not on the path can affect things. Like reverse proxies, load balancers and so on.