This defaults `ip_range_blacklist` to reserved IP ranges and also adds an
`ip_range_whitelist` setting to override it.

Related: #8810
Also a few small improvements.

Signed-off-by: Dirk Klimpel <dirk@klimpel.org>

Pin the docker version for multiarch builds

It seems that letting CircleCI use its default docker version (17.09.0-ce,
apparently) did not interact well with multiarch builds: in particular, we saw
weird effects where running an amd64 build at the same time as an arm64 build
caused the arm64 builds to fail with:

   Error while loading /usr/sbin/dpkg-deb: No such file or directory

Synapse 1.23.1 (2020-12-09)
===========================

Due to the two security issues highlighted below, server administrators are
encouraged to update Synapse. We are not aware of these vulnerabilities being
exploited in the wild.

Security advisory
-----------------

The following issues are fixed in v1.23.1 and v1.24.0.

- There is a denial of service attack
  ([CVE-2020-26257](https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2020-26257))
  against the federation APIs in which future events will not be correctly sent
  to other servers over federation. This affects all servers that participate in
  open federation. (Fixed in [#8776](https://github.com/matrix-org/synapse/pull/8776)).

- Synapse may be affected by OpenSSL
  [CVE-2020-1971](https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2020-1971).
  Synapse administrators should ensure that they have the latest versions of
  the cryptography Python package installed.

To upgrade Synapse along with the cryptography package:

* Administrators using the [`matrix.org` Docker
  image](https://hub.docker.com/r/matrixdotorg/synapse/) or the [Debian/Ubuntu
  packages from
  `matrix.org`](https://github.com/matrix-org/synapse/blob/master/INSTALL.md#matrixorg-packages)
  should ensure that they have version 1.24.0 or 1.23.1 installed: these images include
  the updated packages.
* Administrators who have [installed Synapse from
  source](https://github.com/matrix-org/synapse/blob/master/INSTALL.md#installing-from-source)
  should upgrade the cryptography package within their virtualenv by running:
  ```sh
  <path_to_virtualenv>/bin/pip install 'cryptography>=3.3'
  ```
* Administrators who have installed Synapse from distribution packages should
  consult the information from their distributions.

Bugfixes
--------

- Fix a bug in some federation APIs which could lead to unexpected behaviour if different parameters were set in the URI and the request body. ([\#8776](https://github.com/matrix-org/synapse/issues/8776))

Internal Changes
----------------

- Add a maximum version for pysaml2 on Python 3.5. ([\#8898](https://github.com/matrix-org/synapse/issues/8898))

This pins pysaml2 to < 6.4.0 on Python 3.5, as the last known working version.

* Consistently use room_id from federation request body

Some federation APIs have a redundant `room_id` path param (see
https://github.com/matrix-org/matrix-doc/issues/2330). We should make sure we
consistently use either the path param or the body param, and the body param is
easier.

* Kill off some references to "context"

Once upon a time, "rooms" were known as "contexts". I think this kills of the
last references to "contexts".

Fixes / related to: https://github.com/matrix-org/synapse/issues/6533

This should do essentially the same thing as a robots.txt file telling robots to not index the media repo. https://developers.google.com/search/reference/robots_meta_tag



Signed-off-by: Aaron Raimist <aaron@raim.ist>

This pins pysaml2 to < 6.4.0 on Python 3.5, as the last known working version.

The idea is that the parse_config method of extension modules can raise either a ConfigError or a JsonValidationError,
and it will be magically turned into a legible error message. There's a few components to it:

* Separating the "path" and the "message" parts of a ConfigError, so that we can fiddle with the path bit to turn it
   into an absolute path.
* Generally improving the way ConfigErrors get printed.
* Passing in the config path to load_module so that it can wrap any exceptions that get caught appropriately.

* SsoHandler: remove inheritance from BaseHandler

* Simplify the flow for SSO UIA

We don't need to do all the magic for mapping users when we are doing UIA, so
let's factor that out.

* Call set_avatar_url with target_user, not user_id

Fixes https://github.com/matrix-org/synapse/issues/8871



* Create 8872.bugfix

* Update synapse/rest/admin/users.py

Co-authored-by: Patrick Cloke <clokep@users.noreply.github.com>

* Testing

* Update changelog.d/8872.bugfix

Co-authored-by: Andrew Morgan <1342360+anoadragon453@users.noreply.github.com>

Co-authored-by: Patrick Cloke <clokep@users.noreply.github.com>
Co-authored-by: Andrew Morgan <1342360+anoadragon453@users.noreply.github.com>

Authentication is done by checking a shared secret provided
in the Synapse configuration file.

This is so that we can choose which algorithm to use based on the room ID.

Pusher URLs now must end in `/_matrix/push/v1/notify` per the
specification.

Instead return the proper 400 error.

Synapse 1.24.0rc2 (2020-12-04)
==============================

Bugfixes
--------

- Fix a regression in v1.24.0rc1 which failed to allow SAML mapping providers which were unable to redirect users to an additional page. ([\#8878](https://github.com/matrix-org/synapse/issues/8878))

Internal Changes
----------------

- Add support for the `prometheus_client` newer than 0.9.0. Contributed by Jordan Bancino. ([\#8875](https://github.com/matrix-org/synapse/issues/8875))

This was broken in #8801.

This removes the version pin of the `prometheus_client` dependency, in direct response to #8831. If merged, this will close #8831 

As far as I can tell, no other changes are needed, but as I'm no synapse expert, I'm relying heavily on CI and maintainer reviews for this. My very primitive test of synapse with prometheus_client v0.9.0 on my home server didn't bring up any issues, so we'll see what happens.

Signed-off-by: Jordan Bancino

the constructor is called with a `module_api`.

The spec says we should return `M_FORBIDDEN` when someone tries to register and
registration is disabled.

Remove some unnecessary mocking from the unit tests

UIA: offer only available auth flows