README.rst 16 KB

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  1. .. contents::
  2. Introduction
  3. ============
  4. Matrix is an ambitious new ecosystem for open federated Instant Messaging and
  5. VoIP. The basics you need to know to get up and running are:
  6. - Everything in Matrix happens in a room. Rooms are distributed and do not
  7. exist on any single server. Rooms can be located using convenience aliases
  8. like ``#matrix:matrix.org`` or ``#test:localhost:8448``.
  9. - Matrix user IDs look like ``@matthew:matrix.org`` (although in the future
  10. you will normally refer to yourself and others using a third party identifier
  11. (3PID): email address, phone number, etc rather than manipulating Matrix user IDs)
  12. The overall architecture is::
  13. client <----> homeserver <=====================> homeserver <----> client
  14. https://somewhere.org/_matrix https://elsewhere.net/_matrix
  15. ``#matrix:matrix.org`` is the official support room for Matrix, and can be
  16. accessed by any client from https://matrix.org/docs/projects/try-matrix-now.html or
  17. via IRC bridge at irc://irc.freenode.net/matrix.
  18. Synapse is currently in rapid development, but as of version 0.5 we believe it
  19. is sufficiently stable to be run as an internet-facing service for real usage!
  20. About Matrix
  21. ============
  22. Matrix specifies a set of pragmatic RESTful HTTP JSON APIs as an open standard,
  23. which handle:
  24. - Creating and managing fully distributed chat rooms with no
  25. single points of control or failure
  26. - Eventually-consistent cryptographically secure synchronisation of room
  27. state across a global open network of federated servers and services
  28. - Sending and receiving extensible messages in a room with (optional)
  29. end-to-end encryption[1]
  30. - Inviting, joining, leaving, kicking, banning room members
  31. - Managing user accounts (registration, login, logout)
  32. - Using 3rd Party IDs (3PIDs) such as email addresses, phone numbers,
  33. Facebook accounts to authenticate, identify and discover users on Matrix.
  34. - Placing 1:1 VoIP and Video calls
  35. These APIs are intended to be implemented on a wide range of servers, services
  36. and clients, letting developers build messaging and VoIP functionality on top
  37. of the entirely open Matrix ecosystem rather than using closed or proprietary
  38. solutions. The hope is for Matrix to act as the building blocks for a new
  39. generation of fully open and interoperable messaging and VoIP apps for the
  40. internet.
  41. Synapse is a reference "homeserver" implementation of Matrix from the core
  42. development team at matrix.org, written in Python/Twisted. It is intended to
  43. showcase the concept of Matrix and let folks see the spec in the context of a
  44. codebase and let you run your own homeserver and generally help bootstrap the
  45. ecosystem.
  46. In Matrix, every user runs one or more Matrix clients, which connect through to
  47. a Matrix homeserver. The homeserver stores all their personal chat history and
  48. user account information - much as a mail client connects through to an
  49. IMAP/SMTP server. Just like email, you can either run your own Matrix
  50. homeserver and control and own your own communications and history or use one
  51. hosted by someone else (e.g. matrix.org) - there is no single point of control
  52. or mandatory service provider in Matrix, unlike WhatsApp, Facebook, Hangouts,
  53. etc.
  54. We'd like to invite you to join #matrix:matrix.org (via
  55. https://matrix.org/docs/projects/try-matrix-now.html), run a homeserver, take a look
  56. at the `Matrix spec <https://matrix.org/docs/spec>`_, and experiment with the
  57. `APIs <https://matrix.org/docs/api>`_ and `Client SDKs
  58. <https://matrix.org/docs/projects/try-matrix-now.html#client-sdks>`_.
  59. Thanks for using Matrix!
  60. [1] End-to-end encryption is currently in beta: `blog post <https://matrix.org/blog/2016/11/21/matrixs-olm-end-to-end-encryption-security-assessment-released-and-implemented-cross-platform-on-riot-at-last>`_.
  61. Synapse Installation
  62. ====================
  63. .. _federation:
  64. * For details on how to install synapse, see `<INSTALL.md>`_.
  65. * For specific details on how to configure Synapse for federation see `docs/federate.md <docs/federate.md>`_
  66. Connecting to Synapse from a client
  67. ===================================
  68. The easiest way to try out your new Synapse installation is by connecting to it
  69. from a web client.
  70. Unless you are running a test instance of Synapse on your local machine, in
  71. general, you will need to enable TLS support before you can successfully
  72. connect from a client: see `<INSTALL.md#tls-certificates>`_.
  73. An easy way to get started is to login or register via Riot at
  74. https://riot.im/app/#/login or https://riot.im/app/#/register respectively.
  75. You will need to change the server you are logging into from ``matrix.org``
  76. and instead specify a Homeserver URL of ``https://<server_name>:8448``
  77. (or just ``https://<server_name>`` if you are using a reverse proxy).
  78. (Leave the identity server as the default - see `Identity servers`_.)
  79. If you prefer to use another client, refer to our
  80. `client breakdown <https://matrix.org/docs/projects/clients-matrix>`_.
  81. If all goes well you should at least be able to log in, create a room, and
  82. start sending messages.
  83. .. _`client-user-reg`:
  84. Registering a new user from a client
  85. ------------------------------------
  86. By default, registration of new users via Matrix clients is disabled. To enable
  87. it, specify ``enable_registration: true`` in ``homeserver.yaml``. (It is then
  88. recommended to also set up CAPTCHA - see `<docs/CAPTCHA_SETUP.md>`_.)
  89. Once ``enable_registration`` is set to ``true``, it is possible to register a
  90. user via `riot.im <https://riot.im/app/#/register>`_ or other Matrix clients.
  91. Your new user name will be formed partly from the ``server_name``, and partly
  92. from a localpart you specify when you create the account. Your name will take
  93. the form of::
  94. @localpart:my.domain.name
  95. (pronounced "at localpart on my dot domain dot name").
  96. As when logging in, you will need to specify a "Custom server". Specify your
  97. desired ``localpart`` in the 'User name' box.
  98. ACME setup
  99. ==========
  100. For details on having Synapse manage your federation TLS certificates
  101. automatically, please see `<docs/ACME.md>`_.
  102. Security Note
  103. =============
  104. Matrix serves raw user generated data in some APIs - specifically the `content
  105. repository endpoints <https://matrix.org/docs/spec/client_server/latest.html#get-matrix-media-r0-download-servername-mediaid>`_.
  106. Whilst we have tried to mitigate against possible XSS attacks (e.g.
  107. https://github.com/matrix-org/synapse/pull/1021) we recommend running
  108. matrix homeservers on a dedicated domain name, to limit any malicious user generated
  109. content served to web browsers a matrix API from being able to attack webapps hosted
  110. on the same domain. This is particularly true of sharing a matrix webclient and
  111. server on the same domain.
  112. See https://github.com/vector-im/riot-web/issues/1977 and
  113. https://developer.github.com/changes/2014-04-25-user-content-security for more details.
  114. Upgrading an existing Synapse
  115. =============================
  116. The instructions for upgrading synapse are in `UPGRADE.rst`_.
  117. Please check these instructions as upgrading may require extra steps for some
  118. versions of synapse.
  119. .. _UPGRADE.rst: UPGRADE.rst
  120. Using PostgreSQL
  121. ================
  122. Synapse offers two database engines:
  123. * `SQLite <https://sqlite.org/>`_
  124. * `PostgreSQL <https://www.postgresql.org>`_
  125. By default Synapse uses SQLite in and doing so trades performance for convenience.
  126. SQLite is only recommended in Synapse for testing purposes or for servers with
  127. light workloads.
  128. Almost all installations should opt to use PostreSQL. Advantages include:
  129. * significant performance improvements due to the superior threading and
  130. caching model, smarter query optimiser
  131. * allowing the DB to be run on separate hardware
  132. * allowing basic active/backup high-availability with a "hot spare" synapse
  133. pointing at the same DB master, as well as enabling DB replication in
  134. synapse itself.
  135. For information on how to install and use PostgreSQL, please see
  136. `docs/postgres.md <docs/postgres.md>`_.
  137. .. _reverse-proxy:
  138. Using a reverse proxy with Synapse
  139. ==================================
  140. It is recommended to put a reverse proxy such as
  141. `nginx <https://nginx.org/en/docs/http/ngx_http_proxy_module.html>`_,
  142. `Apache <https://httpd.apache.org/docs/current/mod/mod_proxy_http.html>`_,
  143. `Caddy <https://caddyserver.com/docs/proxy>`_ or
  144. `HAProxy <https://www.haproxy.org/>`_ in front of Synapse. One advantage of
  145. doing so is that it means that you can expose the default https port (443) to
  146. Matrix clients without needing to run Synapse with root privileges.
  147. For information on configuring one, see `<docs/reverse_proxy.md>`_.
  148. Identity Servers
  149. ================
  150. Identity servers have the job of mapping email addresses and other 3rd Party
  151. IDs (3PIDs) to Matrix user IDs, as well as verifying the ownership of 3PIDs
  152. before creating that mapping.
  153. **They are not where accounts or credentials are stored - these live on home
  154. servers. Identity Servers are just for mapping 3rd party IDs to matrix IDs.**
  155. This process is very security-sensitive, as there is obvious risk of spam if it
  156. is too easy to sign up for Matrix accounts or harvest 3PID data. In the longer
  157. term, we hope to create a decentralised system to manage it (`matrix-doc #712
  158. <https://github.com/matrix-org/matrix-doc/issues/712>`_), but in the meantime,
  159. the role of managing trusted identity in the Matrix ecosystem is farmed out to
  160. a cluster of known trusted ecosystem partners, who run 'Matrix Identity
  161. Servers' such as `Sydent <https://github.com/matrix-org/sydent>`_, whose role
  162. is purely to authenticate and track 3PID logins and publish end-user public
  163. keys.
  164. You can host your own copy of Sydent, but this will prevent you reaching other
  165. users in the Matrix ecosystem via their email address, and prevent them finding
  166. you. We therefore recommend that you use one of the centralised identity servers
  167. at ``https://matrix.org`` or ``https://vector.im`` for now.
  168. To reiterate: the Identity server will only be used if you choose to associate
  169. an email address with your account, or send an invite to another user via their
  170. email address.
  171. Password reset
  172. ==============
  173. If a user has registered an email address to their account using an identity
  174. server, they can request a password-reset token via clients such as Riot.
  175. A manual password reset can be done via direct database access as follows.
  176. First calculate the hash of the new password::
  177. $ ~/synapse/env/bin/hash_password
  178. Password:
  179. Confirm password:
  180. $2a$12$xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx
  181. Then update the `users` table in the database::
  182. UPDATE users SET password_hash='$2a$12$xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx'
  183. WHERE name='@test:test.com';
  184. Synapse Development
  185. ===================
  186. Before setting up a development environment for synapse, make sure you have the
  187. system dependencies (such as the python header files) installed - see
  188. `Installing from source <INSTALL.md#installing-from-source>`_.
  189. To check out a synapse for development, clone the git repo into a working
  190. directory of your choice::
  191. git clone https://github.com/matrix-org/synapse.git
  192. cd synapse
  193. Synapse has a number of external dependencies, that are easiest
  194. to install using pip and a virtualenv::
  195. virtualenv -p python3 env
  196. source env/bin/activate
  197. python -m pip install --no-use-pep517 -e ".[all]"
  198. This will run a process of downloading and installing all the needed
  199. dependencies into a virtual env.
  200. Once this is done, you may wish to run Synapse's unit tests, to
  201. check that everything is installed as it should be::
  202. python -m twisted.trial tests
  203. This should end with a 'PASSED' result::
  204. Ran 143 tests in 0.601s
  205. PASSED (successes=143)
  206. Running the Integration Tests
  207. =============================
  208. Synapse is accompanied by `SyTest <https://github.com/matrix-org/sytest>`_,
  209. a Matrix homeserver integration testing suite, which uses HTTP requests to
  210. access the API as a Matrix client would. It is able to run Synapse directly from
  211. the source tree, so installation of the server is not required.
  212. Testing with SyTest is recommended for verifying that changes related to the
  213. Client-Server API are functioning correctly. See the `installation instructions
  214. <https://github.com/matrix-org/sytest#installing>`_ for details.
  215. Building Internal API Documentation
  216. ===================================
  217. Before building internal API documentation install sphinx and
  218. sphinxcontrib-napoleon::
  219. pip install sphinx
  220. pip install sphinxcontrib-napoleon
  221. Building internal API documentation::
  222. python setup.py build_sphinx
  223. Troubleshooting
  224. ===============
  225. Running out of File Handles
  226. ---------------------------
  227. If synapse runs out of file handles, it typically fails badly - live-locking
  228. at 100% CPU, and/or failing to accept new TCP connections (blocking the
  229. connecting client). Matrix currently can legitimately use a lot of file handles,
  230. thanks to busy rooms like #matrix:matrix.org containing hundreds of participating
  231. servers. The first time a server talks in a room it will try to connect
  232. simultaneously to all participating servers, which could exhaust the available
  233. file descriptors between DNS queries & HTTPS sockets, especially if DNS is slow
  234. to respond. (We need to improve the routing algorithm used to be better than
  235. full mesh, but as of March 2019 this hasn't happened yet).
  236. If you hit this failure mode, we recommend increasing the maximum number of
  237. open file handles to be at least 4096 (assuming a default of 1024 or 256).
  238. This is typically done by editing ``/etc/security/limits.conf``
  239. Separately, Synapse may leak file handles if inbound HTTP requests get stuck
  240. during processing - e.g. blocked behind a lock or talking to a remote server etc.
  241. This is best diagnosed by matching up the 'Received request' and 'Processed request'
  242. log lines and looking for any 'Processed request' lines which take more than
  243. a few seconds to execute. Please let us know at #synapse:matrix.org if
  244. you see this failure mode so we can help debug it, however.
  245. Help!! Synapse is slow and eats all my RAM/CPU!
  246. -----------------------------------------------
  247. First, ensure you are running the latest version of Synapse, using Python 3
  248. with a PostgreSQL database.
  249. Synapse's architecture is quite RAM hungry currently - we deliberately
  250. cache a lot of recent room data and metadata in RAM in order to speed up
  251. common requests. We'll improve this in the future, but for now the easiest
  252. way to either reduce the RAM usage (at the risk of slowing things down)
  253. is to set the almost-undocumented ``SYNAPSE_CACHE_FACTOR`` environment
  254. variable. The default is 0.5, which can be decreased to reduce RAM usage
  255. in memory constrained enviroments, or increased if performance starts to
  256. degrade.
  257. However, degraded performance due to a low cache factor, common on
  258. machines with slow disks, often leads to explosions in memory use due
  259. backlogged requests. In this case, reducing the cache factor will make
  260. things worse. Instead, try increasing it drastically. 2.0 is a good
  261. starting value.
  262. Using `libjemalloc <http://jemalloc.net/>`_ can also yield a significant
  263. improvement in overall memory use, and especially in terms of giving back
  264. RAM to the OS. To use it, the library must simply be put in the
  265. LD_PRELOAD environment variable when launching Synapse. On Debian, this
  266. can be done by installing the ``libjemalloc1`` package and adding this
  267. line to ``/etc/default/matrix-synapse``::
  268. LD_PRELOAD=/usr/lib/x86_64-linux-gnu/libjemalloc.so.1
  269. This can make a significant difference on Python 2.7 - it's unclear how
  270. much of an improvement it provides on Python 3.x.
  271. If you're encountering high CPU use by the Synapse process itself, you
  272. may be affected by a bug with presence tracking that leads to a
  273. massive excess of outgoing federation requests (see `discussion
  274. <https://github.com/matrix-org/synapse/issues/3971>`_). If metrics
  275. indicate that your server is also issuing far more outgoing federation
  276. requests than can be accounted for by your users' activity, this is a
  277. likely cause. The misbehavior can be worked around by setting
  278. ``use_presence: false`` in the Synapse config file.
  279. People can't accept room invitations from me
  280. --------------------------------------------
  281. The typical failure mode here is that you send an invitation to someone
  282. to join a room or direct chat, but when they go to accept it, they get an
  283. error (typically along the lines of "Invalid signature"). They might see
  284. something like the following in their logs::
  285. 2019-09-11 19:32:04,271 - synapse.federation.transport.server - 288 - WARNING - GET-11752 - authenticate_request failed: 401: Invalid signature for server <server> with key ed25519:a_EqML: Unable to verify signature for <server>
  286. This is normally caused by a misconfiguration in your reverse-proxy. See
  287. `<docs/reverse_proxy.md>`_ and double-check that your settings are correct.