While working on https://github.com/matrix-org/synapse/issues/5665 I found myself digging into the `Ratelimiter` class and seeing that it was both:
* Rather undocumented, and
* causing a *lot* of config checks
This PR attempts to refactor and comment the `Ratelimiter` class, as well as encourage config file accesses to only be done at instantiation.
Best to be reviewed commit-by-commit.
* Expose `return_html_error`, and allow it to take a Jinja2 template instead of a raw string
* Clean up exception handling in SAML2ResponseResource
* use the existing code in `return_html_error` instead of re-implementing it
(giving it a jinja2 template rather than inventing a new form of template)
* do the exception-catching in the REST layer rather than in the handler
layer, to make sure we catch all exceptions.
The idea here is that if an instance persists an event via the replication HTTP API it can return before we receive that event over replication, which can lead to races where code assumes that persisting an event immediately updates various caches (e.g. current state of the room).
Most of Synapse doesn't hit such races, so we don't do the waiting automagically, instead we do so where necessary to avoid unnecessary delays. We may decide to change our minds here if it turns out there are a lot of subtle races going on.
People probably want to look at this commit by commit.
Bugfixes:
- Hash passwords as early as possible during registration. #7523
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Merge tag 'v1.13.0rc3' into develop
Synapse 1.13.0rc3 (2020-05-18)
Bugfixes:
- Hash passwords as early as possible during registration. #7523
==============================
Bugfixes
--------
- Fix a long-standing bug which could cause messages not to be sent over federation, when state events with state keys matching user IDs (such as custom user statuses) were received. ([\#7376](https://github.com/matrix-org/synapse/issues/7376))
- Restore compatibility with non-compliant clients during the user interactive authentication process, fixing a problem introduced in v1.13.0rc1. ([\#7483](https://github.com/matrix-org/synapse/issues/7483))
Internal Changes
----------------
- Fix linting errors in new version of Flake8. ([\#7470](https://github.com/matrix-org/synapse/issues/7470))
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Merge tag 'v1.13.0rc2' into develop
Synapse 1.13.0rc2 (2020-05-14)
==============================
Bugfixes
--------
- Fix a long-standing bug which could cause messages not to be sent over federation, when state events with state keys matching user IDs (such as custom user statuses) were received. ([\#7376](https://github.com/matrix-org/synapse/issues/7376))
- Restore compatibility with non-compliant clients during the user interactive authentication process, fixing a problem introduced in v1.13.0rc1. ([\#7483](https://github.com/matrix-org/synapse/issues/7483))
Internal Changes
----------------
- Fix linting errors in new version of Flake8. ([\#7470](https://github.com/matrix-org/synapse/issues/7470))
* release-v1.13.0:
Don't UPGRADE database rows
RST indenting
Put rollback instructions in upgrade notes
Fix changelog typo
Oh yeah, RST
Absolute URL it is then
Fix upgrade notes link
Provide summary of upgrade issues in changelog. Fix )
Move next version notes from changelog to upgrade notes
Changelog fixes
1.13.0rc1
Documentation on setting up redis (#7446)
Rework UI Auth session validation for registration (#7455)
Fix errors from malformed log line (#7454)
Drop support for redis.dbid (#7450)
By persisting the user interactive authentication sessions to the database, this fixes
situations where a user hits different works throughout their auth session and also
allows sessions to persist through restarts of Synapse.
If an error happened while processing a SAML AuthN response, or a client
ends up doing a `GET` request to `/authn_response`, then render a
customisable error page rather than a confusing error.
... and set it everywhere it's called.
while we're here, rename it for consistency with `check_user_in_room` (and to
help check that I haven't missed any instances)
This was ill-advised. We can't modify verify_keys here, because the response
object has already been signed by the requested key.
Furthermore, it's somewhat unnecessary because existing versions of Synapse
(which get upset that the notary key isn't present in verify_keys) will fall
back to a direct fetch via `/key/v2/server`.
Also: more tests for fetching keys via perspectives: it would be nice if we actually tested when our fetcher can't talk to our notary impl.
* Kill off redundant SynapseRequestFactory
We already get the Site via the Channel, so there's no need for a dedicated
RequestFactory: we can just use the right constructor.
* Workaround for error when fetching notary's own key
As a notary server, when we return our own keys, include all of our signing
keys in verify_keys.
This is a workaround for #6596.
* Remove redundant python2 support code
`str.decode()` doesn't exist on python3, so presumably this code was doing
nothing
* Filter out pushers with corrupt data
When we get a row with unparsable json, drop the row, rather than returning a
row with null `data`, which will then cause an explosion later on.
* Improve logging when we can't start a pusher
Log the ID to help us understand the problem
* Make email pusher setup more robust
We know we'll have a `data` member, since that comes from the database. What we
*don't* know is if that is a dict, and if that has a `brand` member, and if
that member is a string.
We were doing this in a number of places which meant that some login
code paths incremented the counter multiple times.
It was also applying ratelimiting to UIA endpoints, which was probably
not intentional.
In particular, some custom auth modules were calling
`check_user_exists`, which incremented the counters, meaning that people
would fail to login sometimes.
The `http_proxy` and `HTTPS_PROXY` env vars can be set to a `host[:port]` value which should point to a proxy.
The address of the proxy should be excluded from IP blacklists such as the `url_preview_ip_range_blacklist`.
The proxy will then be used for
* push
* url previews
* phone-home stats
* recaptcha validation
* CAS auth validation
It will *not* be used for:
* Application Services
* Identity servers
* Outbound federation
* In worker configurations, connections from workers to masters
Fixes#4198.
This fixed the weirdness of 400 vs 404 as http status code in the case
the filter id is not known by the server.
As e.g. matrix-js-sdk expects 404 to catch this situation this leads
to unwanted behaviour.
Pillow will use nearest neighbour as the resampling algorithm if the
source image is either 1-bit or a color palette using 8 bits. If we
convert to RGB before scaling, we'll probably get a better result.
Doing a password reset via SMS has never worked, and in any case is a silly
idea because msisdn recycling is a thing.
See also matrix-org/matrix-doc#2303.
because, frankly, it looked like it was written by an axe-murderer.
This should be a non-functional change, except that where `m.login.dummy` was
previously advertised *before* `m.login.terms`, it will now be advertised
afterwards. AFAICT that should have no effect, and will be more consistent with
the flows that involve passing a 3pid.
As MSC2263 states, m.require_identity_server must be set to false when it does not require an identity server to be provided by the client for the purposes of email registration or password reset.
Adds an m.require_identity_server flag to /versionss unstable_flags section. This will advertise that Synapse no longer needs id_server as a parameter.
Implements MSC2290. This PR adds two new endpoints, /unstable/account/3pid/add and /unstable/account/3pid/bind. Depending on the progress of that MSC the unstable prefix may go away.
This PR also removes the blacklist on some 3PID tests which occurs in #6042, as the corresponding Sytest PR changes them to use the new endpoints.
Finally, it also modifies the account deactivation code such that it doesn't just try to deactivate 3PIDs that were bound to the user's account, but any 3PIDs that were bound through the homeserver on that user's account.
Fixes#6066
This register endpoint should be disabled if registration is disabled, otherwise we're giving anyone the ability to check if a username exists on a server when we don't need to be.
Error code is 403 (Forbidden) as that's the same returned by /register when registration is disabled.
Remove trailing slash ability from the password reset submit_token endpoint. Since we provide the link in an email, and have never sent it with a trailing slash, there's no point for us to accept them on the endpoint.
Removes the POST method from `/password_reset/<medium>/submit_token/` as it's only used by phone number verification which Synapse does not support yet.
We want to assign unique mxids to saml users based on an incrementing
suffix. For that to work, we need to record the allocated mxid in a separate
table.
This is a combination of a few different PRs, finally all being merged into `develop`:
* #5875
* #5876
* #5868 (This one added the `/versions` flag but the flag itself was actually [backed out](891afb57cb (diff-e591d42d30690ffb79f63bb726200891)) in #5969. What's left is just giving /versions access to the config file, which could be useful in the future)
* #5835
* #5969
* #5940
Clients should not actually use the new registration functionality until https://github.com/matrix-org/synapse/pull/5972 is merged.
UPGRADE.rst, changelog entries and config file changes should all be reviewed closely before this PR is merged.
* Ensure the list media admin API is always available
This API is required for some external media repo implementations to operate (mostly for doing quarantine operations on a room).
* changelog
Remove all the "double return" statements which were a result of us removing all the instances of
```
defer.returnValue(...)
return
```
statements when we switched to python3 fully.
Python will return a tuple whether there are parentheses around the returned values or not.
I'm just sick of my editor complaining about this all over the place :)
This type of registration was probably never used. It only includes the
user name in the HMAC but not the password.
Shared secret registration is still available via
client/r0/admin/register.
Signed-off-by: Manuel Stahl <manuel.stahl@awesome-technologies.de>
Fixes#5833
The emailconfig code was attempting to pull incorrect config file names. This corrects that, while also marking a difference between a config file variable that's a filepath versus a str containing HTML.
--------
- Fix a regression introduced in v1.2.0rc1 which led to incorrect labels on some prometheus metrics. ([\#5734](https://github.com/matrix-org/synapse/issues/5734))
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Merge tag 'v1.2.0rc2' into develop
Bugfixes
--------
- Fix a regression introduced in v1.2.0rc1 which led to incorrect labels on some prometheus metrics. ([\#5734](https://github.com/matrix-org/synapse/issues/5734))
* Fix servlet metric names
Co-Authored-By: Richard van der Hoff <1389908+richvdh@users.noreply.github.com>
* Remove redundant check
* Cover all return paths
First of all, let's get rid of `TOKEN_NOT_FOUND_HTTP_STATUS`. It was a hack we
did at one point when it was possible to return either a 403 or a 401 if the
creds were missing. We always return a 401 in these cases now (thankfully), so
it's not needed.
Let's also stop abusing `AuthError` for these cases. Honestly they have nothing
that relates them to the other places that `AuthError` is used, other than the
fact that they are loosely under the 'Auth' banner. It makes no sense for them
to share exception classes.
Instead, let's add a couple of new exception classes: `InvalidClientTokenError`
and `MissingClientTokenError`, for the `M_UNKNOWN_TOKEN` and `M_MISSING_TOKEN`
cases respectively - and an `InvalidClientCredentialsError` base class for the
two of them.
A fix for PR #5626, which returned the original event content as part of a call to /relations.
Only problem was that we were attempting to aggregate the relations on top of it when we did so. We now set bundle_aggregations to False in the get_event call.
We also do this when pulling the relation events as well, because edits of edits are not something we'd like to support here.
When asking for the relations of an event, include the original event in the response. This will mostly be used for efficiently showing edit history, but could be useful in other circumstances.
Nothing uses this now, so we can remove the dead code, and clean up the
API.
Since we're changing the shape of the return value anyway, we take the
opportunity to give the method a better name.
* SAML2 Improvements and redirect stuff
Signed-off-by: Alexander Trost <galexrt@googlemail.com>
* Code cleanups and simplifications.
Also: share the saml client between redirect and response handlers.
* changelog
* Revert redundant changes to static js
* Move all the saml stuff out to a centralised handler
* Add support for tracking SAML2 sessions.
This allows us to correctly handle `allow_unsolicited: False`.
* update sample config
* cleanups
* update sample config
* rename BaseSSORedirectServlet for consistency
* Address review comments
Moves the warning about password resets being disabled to the point where a user actually tries to reset their password. Is this an appropriate place for it to happen?
Also removed the disabling of msisdn password resets when you don't have an email config, as that just doesn't make sense.
Also change the error a user receives upon disabled passwords to specify that only email-based password reset is disabled.
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
This fixes a bug which were causing the "event_format" field to be
ignored in the filter of requests to the `/messages` endpoint of the
CS API.
Signed-off-by: Eisha Chen-yen-su <chenyensu0@gmail.com>
Replaces DEFAULT_ROOM_VERSION constant with a method that first checks the config, then returns a hardcoded value if the option is not present.
That hardcoded value is now located in the server.py config file.
We checked that 3pids were not already in use before we checked if
we were going to return the account previously registered in the
same UI auth session, in which case the 3pids will definitely
be in use.
https://github.com/vector-im/riot-web/issues/9586
Prevents a SynapseError being raised inside of a IResolutionReceiver and instead opts to just return 0 results. This thus means that we have to lump a failed lookup and a blacklisted lookup together with the same error message, but the substitute should be generic enough to cover both cases.
It's more natural for the user if the bit that takes them away
from the registration flow comes last. Adding the dummy stage allows
us to do the stages in this order without the ambiguity.
This allows the client to complete the email last which is more
natual for the user. Without this stage, if the client would
complete the recaptcha (and terms, if enabled) stages and then the
registration request would complete because you've now completed a
flow, even if you were intending to complete the flow that's the
same except has email auth at the end.
Adding a dummy auth stage to the recaptcha-only flow means it's
always unambiguous which flow the client was trying to complete.
Longer term we should think about changing the protocol so the
client explicitly says which flow it's trying to complete.
vector-im/riot-web#9586
This allows the client to complete the email last which is more
natual for the user. Without this stage, if the client would
complete the recaptcha (and terms, if enabled) stages and then the
registration request would complete because you've now completed a
flow, even if you were intending to complete the flow that's the
same except has email auth at the end.
Adding a dummy auth stage to the recaptcha-only flow means it's
always unambiguous which flow the client was trying to complete.
Longer term we should think about changing the protocol so the
client explicitly says which flow it's trying to complete.
https://github.com/vector-im/riot-web/issues/9586
This commit adds two config options:
* `restrict_public_rooms_to_local_users`
Requires auth to fetch the public rooms directory through the CS API and disables fetching it through the federation API.
* `require_auth_for_profile_requests`
When set to `true`, requires that requests to `/profile` over the CS API are authenticated, and only returns the user's profile if the requester shares a room with the profile's owner, as per MSC1301.
MSC1301 also specifies a behaviour for federation (only returning the profile if the server asking for it shares a room with the profile's owner), but that's currently really non-trivial to do in a not too expensive way. Next step is writing down a MSC that allows a HS to specify which user sent the profile query. In this implementation, Synapse won't send a profile query over federation if it doesn't believe it already shares a room with the profile's owner, though.
Groups have been intentionally omitted from this commit.
This endpoint isn't much use for its intended purpose if you first need to get
yourself an admin's auth token.
I've restricted it to the `/_synapse/admin` path to make it a bit easier to
lock down for those concerned about exposing this information. I don't imagine
anyone is using it in anger currently.
By default the homeserver will use the identity server used during the
binding of the 3PID to unbind the 3PID. However, we need to allow
clients to explicitly ask the homeserver to unbind via a particular
identity server, for the case where the 3PID was bound out of band from
the homeserver.
Implements MSC915.
Adds a new method, check_3pid_auth, which gives password providers
the chance to allow authentication with third-party identifiers such
as email or msisdn.
Currently the explanation message is sent to the abuse room before any
users are forced joined, which means it tends to get lost in the backlog
of joins.
So instead we send the message *after* we've forced joined everyone.
* Rate-limiting for registration
* Add unit test for registration rate limiting
* Add config parameters for rate limiting on auth endpoints
* Doc
* Fix doc of rate limiting function
Co-Authored-By: babolivier <contact@brendanabolivier.com>
* Incorporate review
* Fix config parsing
* Fix linting errors
* Set default config for auth rate limiting
* Fix tests
* Add changelog
* Advance reactor instead of mocked clock
* Move parameters to registration specific config and give them more sensible default values
* Remove unused config options
* Don't mock the rate limiter un MAU tests
* Rename _register_with_store into register_with_store
* Make CI happy
* Remove unused import
* Update sample config
* Fix ratelimiting test for py2
* Add non-guest test
This allows registration to be handled by a worker, though the actual
write to the database still happens on master.
Note: due to the in-memory session map all registration requests must be
handled by the same worker.
* Correctly retry and back off if we get a HTTPerror response
* Refactor request sending to have better excpetions
MatrixFederationHttpClient blindly reraised exceptions to the caller
without differentiating "expected" failures (e.g. connection timeouts
etc) versus more severe problems (e.g. programming errors).
This commit adds a RequestSendFailed exception that is raised when
"expected" failures happen, allowing the TransactionQueue to log them as
warnings while allowing us to log other exceptions as actual exceptions.
Allow for the creation of a support user.
A support user can access the server, join rooms, interact with other users, but does not appear in the user directory nor does it contribute to monthly active user limits.
This implements both a SAML2 metadata endpoint (at
`/_matrix/saml2/metadata.xml`), and a SAML2 response receiver (at
`/_matrix/saml2/authn_response`). If the SAML2 response matches what's been
configured, we complete the SSO login flow by redirecting to the client url
(aka `RelayState` in SAML2 jargon) with a login token.
What we don't yet have is anything to build a SAML2 request and redirect the
user to the identity provider. That is left as an exercise for the reader.
This is mostly factoring out the post-CAS-login code to somewhere we can reuse
it for other SSO flows, but it also fixes the userid mapping while we're at it.
* Rip out half-implemented m.login.saml2 support
This was implemented in an odd way that left most of the work to the client, in
a way that I really didn't understand. It's going to be a pain to maintain, so
let's start by ripping it out.
* drop undocumented dependency on dateutil
It turns out we were relying on dateutil being pulled in transitively by
pysaml2. There's no need for that bloat.
* Clean up the CSS for the fallback login form
I was finding this hard to work with, so simplify a bunch of things. Each
flow is now a form inside a div of class login_flow.
The login_flow class now has a fixed width, as that looks much better than each
flow having a differnt width.
* Support m.login.sso
MSC1721 renames m.login.cas to m.login.sso. This implements the change
(retaining support for m.login.cas for older clients).
* changelog
Currently when fetching state groups from the data store we make two
hits two the database: once for members and once for non-members (unless
request is filtered to one or the other). This adds needless load to the
datbase, so this PR refactors the lookup to make only a single database
hit.
Broadly three things here:
* disable W504 which seems a bit whacko
* remove a bunch of `as e` expressions from exception handlers that don't use
them
* use `r""` for strings which include backslashes
Also, we don't use pep8 any more, so we can get rid of the duplicate config
there.
Wrap calls to deferToThread() in a thing which uses a child logcontext to
attribute CPU usage to the right request.
While we're in the area, remove the logcontext_tracer stuff, which is never
used, and afaik doesn't work.
Fixes#4064
Synapse doesn’t allow for media resources to be played directly from
Chrome. It is a problem for users on other networks (e.g. IRC)
communicating with Matrix users through a gateway. The gateway sends
them the raw URL for the resource when a Matrix user uploads a video
and the video cannot be played directly in Chrome using that URL.
Chrome argues it is not authorized to play the video because of the
Content Security Policy. Chrome checks for the "media-src" policy which
is missing, and defauts to the "default-src" policy which is "none".
As Synapse already sends "object-src: 'self'" I thought it wouldn’t be
a problem to add "media-src: 'self'" to the CSP to fix this problem.
ExpiringCache required that `start()` be called before it would actually
start expiring entries. A number of places didn't do that.
This PR removes `start` from ExpiringCache, and automatically starts
backround reaping process on creation instead.
Continues from uhoreg's branch
This just fixed the errcode on /room_keys/version if no backup and
updates the schema delta to be on the latest so it gets run
Older identity servers may not support the unbind 3pid request, so we
shouldn't fail the requests if we received one of 400/404/501. The
request still fails if we receive e.g. 500 responses, allowing clients
to retry requests on transient identity server errors that otherwise do
support the API.
Fixes#3661
Make sure that the user has permission to view the requeseted event for
/event/{eventId} and /room/{roomId}/event/{eventId} requests.
Also check that the event is in the given room for
/room/{roomId}/event/{eventId}, for sanity.
This commit replaces SynapseError.from_http_response_exception with
HttpResponseException.to_synapse_error.
The new method actually returns a ProxiedRequestError, which allows us to pass
through additional metadata from the API call.
It turns out that looping_call does check the deferred returned by its
callback, and (at least in the case of client_ips), we were relying on this,
and I broke it in #3604.
Update run_as_background_process to return the deferred, and make sure we
return it to clock.looping_call.
