Adds new config option `cleanup_extremities_with_dummy_events` which
periodically sends dummy events to rooms with more than 10 extremities.
THIS IS REALLY EXPERIMENTAL.
Some keys are stored in the synapse database with a null valid_until_ms
which caused an exception to be thrown when using that key. We fix this
by treating nulls as zeroes, i.e. they keys will match verification
requests with a minimum_valid_until_ms of zero (i.e. don't validate ts)
but will not match requests with a non-zero minimum_valid_until_ms.
Fixes#5391.
Sends password reset emails from the homeserver instead of proxying to the identity server. This is now the default behaviour for security reasons. If you wish to continue proxying password reset requests to the identity server you must now enable the email.trust_identity_server_for_password_resets option.
This PR is a culmination of 3 smaller PRs which have each been separately reviewed:
* #5308
* #5345
* #5368
There are a few changes going on here:
* We make checking the signature on a key server response optional: if no
verify_keys are specified, we trust to TLS to validate the connection.
* We change the default config so that it does not require responses to be
signed by the old key.
* We replace the old 'perspectives' config with 'trusted_key_servers', which
is also formatted slightly differently.
* We emit a warning to the logs every time we trust a key server response
signed by the old key.
* Fix background updates to handle redactions/rejections
In background updates based on current state delta stream we need to
handle that we may not have all the events (or at least that
`get_events` may raise an exception).
Also:
* rename VerifyKeyRequest->VerifyJsonRequest
* calculate key_ids on VerifyJsonRequest construction
* refactor things to pass around VerifyJsonRequests instead of 4-tuples
When handling incoming federation requests, make sure that we have an
up-to-date copy of the signing key.
We do not yet enforce the validity period for event signatures.
When enabling the account validity feature, Synapse will look at startup for registered account without an expiration date, and will set one equals to 'now + validity_period' for them. On large servers, it can mean that a large number of users will have the same expiration date, which means that they will all be sent a renewal email at the same time, which isn't ideal.
In order to mitigate this, this PR allows server admins to define a 'max_delta' so that the expiration date is a random value in the [now + validity_period ; now + validity_period + max_delta] range. This allows renewal emails to be progressively sent over a configured period instead of being sent all in one big batch.
