fix: disable CSRF checks in dev

[Rich-Harris]

#14309 (comment)

closes #14309

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[svelte-docs-bot]

Preview: https://svelte-dev-git-preview-kit-14335-svelte.vercel.app/

[dummdidumm]

worth a callout in the docs somewhere? not sure where, and not in any way blocking

[Rich-Harris]

good point — added to the csrf.trustedOrigins inline docs

[khromov]

@Rich-Harris I've talked to people on Discord that seemed to be running "npm run dev" in production. It's not a valid use case but I wonder if we won't accidentally enable a sudden security hole for these people, which can come back in form of badwill? This change sounds like something for Kit 3.x imho. Wouldn't it be possible to have remote functions respect csrf.checkOrigin?

[Rich-Harris]

I... what?

How? How does someone end up in that situation? It's literally called npm run dev.

Wouldn't it be possible to have remote functions respect csrf.checkOrigin?

That's a separate conversation to 'should the origin be checked?' and the answer is no — if something other than your own origin is calling remote functions, it's a bad request, period