synapse/docs/jwt.md

91 lines
3.2 KiB
Markdown
Raw Normal View History

# JWT Login Type
Synapse comes with a non-standard login type to support
[JSON Web Tokens](https://en.wikipedia.org/wiki/JSON_Web_Token). In general the
documentation for
[the login endpoint](https://matrix.org/docs/spec/client_server/r0.6.1#login)
is still valid (and the mechanism works similarly to the
[token based login](https://matrix.org/docs/spec/client_server/r0.6.1#token-based)).
To log in using a JSON Web Token, clients should submit a `/login` request as
follows:
```json
{
"type": "org.matrix.login.jwt",
"token": "<jwt>"
}
```
Note that the login type of `m.login.jwt` is supported, but is deprecated. This
will be removed in a future version of Synapse.
The `jwt` should encode the local part of the user ID as the standard `sub`
claim. In the case that the token is not valid, the homeserver must respond with
`401 Unauthorized` and an error code of `M_UNAUTHORIZED`.
(Note that this differs from the token based logins which return a
`403 Forbidden` and an error code of `M_FORBIDDEN` if an error occurs.)
As with other login types, there are additional fields (e.g. `device_id` and
`initial_device_display_name`) which can be included in the above request.
## Preparing Synapse
The JSON Web Token integration in Synapse uses the
[`PyJWT`](https://pypi.org/project/pyjwt/) library, which must be installed
as follows:
* The relevant libraries are included in the Docker images and Debian packages
provided by `matrix.org` so no further action is needed.
* If you installed Synapse into a virtualenv, run `/path/to/env/bin/pip
install synapse[pyjwt]` to install the necessary dependencies.
* For other installation mechanisms, see the documentation provided by the
maintainer.
To enable the JSON web token integration, you should then add an `jwt_config` section
to your configuration file (or uncomment the `enabled: true` line in the
existing section). See [sample_config.yaml](./sample_config.yaml) for some
sample settings.
## How to test JWT as a developer
Although JSON Web Tokens are typically generated from an external server, the
examples below use [PyJWT](https://pyjwt.readthedocs.io/en/latest/) directly.
1. Configure Synapse with JWT logins:
```yaml
jwt_config:
enabled: true
secret: "my-secret-token"
algorithm: "HS256"
```
2. Generate a JSON web token:
```bash
$ pyjwt --key=my-secret-token --alg=HS256 encode sub=test-user
eyJ0eXAiOiJKV1QiLCJhbGciOiJIUzI1NiJ9.eyJzdWIiOiJ0ZXN0LXVzZXIifQ.Ag71GT8v01UO3w80aqRPTeuVPBIBZkYhNTJJ-_-zQIc
```
3. Query for the login types and ensure `org.matrix.login.jwt` is there:
```bash
curl http://localhost:8080/_matrix/client/r0/login
```
4. Login used the generated JSON web token from above:
```bash
$ curl http://localhost:8082/_matrix/client/r0/login -X POST \
--data '{"type":"org.matrix.login.jwt","token":"eyJ0eXAiOiJKV1QiLCJhbGciOiJIUzI1NiJ9.eyJzdWIiOiJ0ZXN0LXVzZXIifQ.Ag71GT8v01UO3w80aqRPTeuVPBIBZkYhNTJJ-_-zQIc"}'
{
"access_token": "<access token>",
"device_id": "ACBDEFGHI",
"home_server": "localhost:8080",
"user_id": "@test-user:localhost:8480"
}
```
You should now be able to use the returned access token to query the client API.