matrix-spec/content/rooms/fragments/v5-signing-requirements.md

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When validating event signatures, servers MUST enforce the
`valid_until_ts` property from a key request is at least as large as the
`origin_server_ts` for the event being validated. Servers missing a copy
of the signing key MUST try to obtain one via the [GET
/\_matrix/key/v2/server](/server-server-api#get_matrixkeyv2serverkeyid)
or [POST
/\_matrix/key/v2/query](/server-server-api#post_matrixkeyv2query)
APIs. When using the `/query` endpoint, servers MUST set the
`minimum_valid_until_ts` property to prompt the notary server to attempt
to refresh the key if appropriate.

Servers MUST use the lesser of `valid_until_ts` and 7 days into the
future when determining if a key is valid. This is to avoid a situation
where an attacker publishes a key which is valid for a significant
amount of time without a way for the homeserver owner to revoke it.
Hide room version fragments from table of contents (#3479) The entries were text-less and not really helping anyone. They are included as pages because we need them for templating, but we don't need people to be able to land on them directly. 3 years ago			`---`
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Fully specify room versions (#3432) * Fully specify room versions * Misc typo clarifications * Try to clarify redactions a bit * Update content/client-server-api/_index.md Co-authored-by: Richard van der Hoff <1389908+richvdh@users.noreply.github.com> * Update content/rooms/v6.md Co-authored-by: Richard van der Hoff <1389908+richvdh@users.noreply.github.com> * Update content/rooms/v6.md Co-authored-by: Richard van der Hoff <1389908+richvdh@users.noreply.github.com> * Better describe client considerations * Doc template params * Move redaction "new stuff" to v3 * Remove unhelpful sentences about "here follows unchanged stuff" * Simplify event signing text * Clean up handling redactions sections * Move v4's event schema to unchanged section * Update content/rooms/v4.md Co-authored-by: Richard van der Hoff <1389908+richvdh@users.noreply.github.com> Co-authored-by: Richard van der Hoff <1389908+richvdh@users.noreply.github.com> 3 years ago			`When validating event signatures, servers MUST enforce the`
			`valid_until_ts` property from a key request is at least as large as the
			`origin_server_ts` for the event being validated. Servers missing a copy
			`of the signing key MUST try to obtain one via the [GET`
			`/\_matrix/key/v2/server](/server-server-api#get_matrixkeyv2serverkeyid)`
			`or [POST`
			`/\_matrix/key/v2/query](/server-server-api#post_matrixkeyv2query)`
			APIs. When using the `/query` endpoint, servers MUST set the
			`minimum_valid_until_ts` property to prompt the notary server to attempt
			`to refresh the key if appropriate.`

			Servers MUST use the lesser of `valid_until_ts` and 7 days into the
			`future when determining if a key is valid. This is to avoid a situation`
			`where an attacker publishes a key which is valid for a significant`
			`amount of time without a way for the homeserver owner to revoke it.`