firezone/elixir

Welcome to Elixir-land!

This README provides an overview for running and managing Firezone's Elixir-based control plane.

Running Control Plane for local development

You can use the Top-Level Docker Compose to start any services locally. The web and api compose services are built application releases that are pretty much the same as the ones we run in production, while the elixir compose service runs raw Elixir code, without a built release.

This means you'll want to use the elixir compose service to run Mix tasks and any Elixir code on-the-fly, but you can't do that in web/api so easily because Elixir strips out Mix and other tooling when building an application release.

elixir additionally caches _build and node_modules to speed up compilation time and syncs /apps, /config and other folders with the host machine.

# Make sure to run this every time code in elixir/ changes,
# docker doesn't do that for you!
❯ docker-compose build

# Create the database
#
# Hint: you can run any mix commands like this,
# eg. mix ecto.reset will reset your database
#
# Also to drop the database you need to stop all active connections,
# so if you get an error stop all services first:
#
#   docker-compose down
#
# Or you can just run both reset and seed in one-liner:
#
#   docker-compose run elixir /bin/sh -c "cd apps/domain && mix do ecto.reset, ecto.seed"
#
❯ docker-compose run elixir /bin/sh -c "cd apps/domain && mix ecto.create"

# Ensure database is migrated before running seeds
❯ docker-compose run api bin/migrate
# or
❯ docker-compose run elixir /bin/sh -c "cd apps/domain && mix ecto.migrate"

# Seed the database
# Hint: some access tokens will be generated and written to stdout,
# don't forget to save them for later
❯ docker-compose run api bin/seed
# or
❯ docker-compose run elixir /bin/sh -c "cd apps/domain && mix ecto.seed"

# Start the API service for control plane sockets while listening to STDIN (where you will see all the logs)
❯ docker-compose up api --build

Now you can verify that it's working by connecting to a websocket:

Gateway

❯ export GATEWAY_TOKEN_FROM_SEEDS="SFMyNTY.g2gDaAJtAAAAJDNjZWYwNTY2LWFkZmQtNDhmZS1hMGYxLTU4MDY3OTYwOGY2Zm0AAABAamp0enhSRkpQWkdCYy1vQ1o5RHkyRndqd2FIWE1BVWRwenVScjJzUnJvcHg3NS16bmhfeHBfNWJUNU9uby1yYm4GAJXr4emIAWIAAVGA.jz0s-NohxgdAXeRMjIQ9kLBOyd7CmKXWi2FHY-Op8GM"
❯ websocat --header="User-Agent: iOS/12.7 (iPhone) connlib/0.7.412" "ws://127.0.0.1:8081/gateway/websocket?token=${GATEWAY_TOKEN_FROM_SEEDS}&external_id=thisisrandomandpersistent&name_suffix=kkX1&public_key=kceI60D6PrwOIiGoVz6hD7VYCgD1H57IVQlPJTTieUE="

Relay

❯ export RELAY_TOKEN_FROM_SEEDS="SFMyNTY.g2gDaAJtAAAAJDcyODZiNTNkLTA3M2UtNGM0MS05ZmYxLWNjODQ1MWRhZDI5OW0AAABARVg3N0dhMEhLSlVWTGdjcE1yTjZIYXRkR25mdkFEWVFyUmpVV1d5VHFxdDdCYVVkRVUzbzktRmJCbFJkSU5JS24GAMDq4emIAWIAAVGA.fLlZsUMS0VJ4RCN146QzUuINmGubpsxoyIf3uhRHdiQ"
❯ websocat --header="User-Agent: Linux/5.2.6 (Debian; x86_64) relay/0.7.412" "ws://127.0.0.1:8081/relay/websocket?token=${RELAY_TOKEN_FROM_SEEDS}&ipv4=24.12.79.100&ipv6=4d36:aa7f:473c:4c61:6b9e:2416:9917:55cc"

# Here is what you will see in docker logs firezone-api-1
# {"time":"2023-06-05T23:16:01.537Z","severity":"info","message":"CONNECTED TO API.Relay.Socket in 251ms\n  Transport: :websocket\n  Serializer: Phoenix.Socket.V1.JSONSerializer\n  Parameters: %{\"ipv4\" => \"24.12.79.100\", \"ipv6\" => \"4d36:aa7f:473c:4c61:6b9e:2416:9917:55cc\", \"stamp_secret\" => \"[FILTERED]\", \"token\" => \"[FILTERED]\"}","metadata":{"domain":["elixir"],"erl_level":"info"}}

# After this you need to join the `relay` topic and pass a `stamp_secret` in the payload.
# For details on this structure see https://hexdocs.pm/phoenix/Phoenix.Socket.Message.html
> {"event":"phx_join","topic":"relay","payload":{"stamp_secret":"makemerandomplz"},"ref":"unique_string_ref","join_ref":"unique_join_ref"}

{"event":"phx_reply","payload":{"response":{},"status":"ok"},"ref":"unique_string_ref","topic":"relay"}
{"event":"init","payload":{},"ref":null,"topic":"relay"}

Device

❯ export CLIENT_TOKEN_FROM_SEEDS="SFMyNTY.g2gDaANkAAhpZGVudGl0eW0AAAAkN2RhN2QxY2QtMTExYy00NGE3LWI1YWMtNDAyN2I5ZDIzMGU1bQAAACDZI3ehOZSu3JOSMREkvzrtKjs8jkrW6fpbVw9opDYmi24GANjCD-qIAWIB4TOA.XhoLEDjIzuv1SXEVUV6lfIHW12n5-J5aBDUKCl8ovMk"

# Panel will only accept token if it's coming with this User-Agent header and from IP 172.28.0.1
❯ export CLIENT_USER_AGENT="iOS/12.5 (iPhone) connlib/0.7.412"

❯ websocat --header="User-Agent: ${CLIENT_USER_AGENT}" "ws://127.0.0.1:8081/device/websocket?token=${CLIENT_TOKEN_FROM_SEEDS}&external_id=thisisrandomandpersistent&name_suffix=kkX1&public_key=kceI60D6PrwOIiGoVz6hD7VYCgD1H57IVQlPJTTieUE="

# Here is what you will see in docker logs firezone-api-1
# firezone-api-1  | {"domain":["elixir"],"erl_level":"info","logging.googleapis.com/sourceLocation":{"file":"lib/phoenix/logger.ex","line":306,"function":"Elixir.Phoenix.Logger.phoenix_socket_connected/4"},"message":"CONNECTED TO API.Device.Socket in 83ms\n  Transport: :websocket\n  Serializer: Phoenix.Socket.V1.JSONSerializer\n  Parameters: %{\"external_id\" => \"thisisrandomandpersistent\", \"name_suffix\" => \"kkX1\", \"public_key\" => \"[FILTERED]\", \"token\" => \"[FILTERED]\"}","severity":"INFO","time":"2023-06-23T21:01:49.566Z"}

# After this you need to join the `device` topic and pass a `stamp_secret` in the payload.
# For details on this structure see https://hexdocs.pm/phoenix/Phoenix.Socket.Message.html
❯ {"event":"phx_join","topic":"device","payload":{},"ref":"unique_string_ref","join_ref":"unique_join_ref"}

{"ref":"unique_string_ref","topic":"device","event":"phx_reply","payload":{"status":"ok","response":{}}}
{"ref":null,"topic":"device","event":"init","payload":{"interface":{"ipv6":"fd00:2011:1111::11:f4bd","upstream_dns":[],"ipv4":"100.71.71.245"},"resources":[{"id":"4429d3aa-53ea-4c03-9435-4dee2899672b","name":"172.20.0.1/16","type":"cidr","address":"172.20.0.0/16"},{"id":"85a1cffc-70d3-46dd-aa6b-776192af7b06","name":"gitlab.mycorp.com","type":"dns","address":"gitlab.mycorp.com","ipv6":"fd00:2011:1111::5:b370","ipv4":"100.85.109.146"}]}}

# List online relays for a Resource
❯ {"event":"list_relays","topic":"device","payload":{"resource_id":"4429d3aa-53ea-4c03-9435-4dee2899672b"},"ref":"unique_list_relays_ref"}

{"ref":"unique_list_relays_ref","topic":"device","event":"phx_reply","payload":{"status":"ok","response":{"relays":[{"type":"stun","uri":"stun:172.28.0.101:3478"},{"type":"turn","username":"1719090081:UVxHhieTJWaD8_Sg","password":"Ml65XDZyYpuBiEIvk/q0Zy6EEJ1ZwGa4pWztXFP+tOo","uri":"turn:172.28.0.101:3478","expires_at":1719090081}],"resource_id":"4429d3aa-53ea-4c03-9435-4dee2899672b"}}}

# Initiate connection to a resource
❯ {"event":"request_connection","topic":"device","payload":{"resource_id":"4429d3aa-53ea-4c03-9435-4dee2899672b","device_rtc_session_description":"RTC_SD","device_preshared_key":"+HapiGI5UdeRjKuKTwk4ZPPYpCnlXHvvqebcIevL+2A="},"ref":"unique_request_connection_ref"}

Note: when you run multiple commands it can hang because Phoenix expects a heartbeat packet every 5 seconds, so it can kill your websocket if you send commands slower than that.

You can reset the database (eg. when there is a migration that breaks data model for unreleased versions) using following command:

❯ docker-compose run elixir /bin/sh -c "cd apps/domain && mix ecto.reset"

Stopping everything is easy too:

docker-compose down

Useful commands for local testing and debugging

Connecting to an IEx interactive console:

❯ docker-compose run elixir /bin/sh -c "cd apps/domain && iex -S mix"

Connecting to a running api/web instance shell:

❯ docker exec -it firezone-api-1 sh
/app

Connecting to a running api/web instance to run Elixir code from them:

# Start all services in daemon mode (in background)
❯ docker-compose up -d --build

# Connect to a running API node
❯ docker exec -it firezone-api-1 bin/api remote
Erlang/OTP 25 [erts-13.1.4] [source] [64-bit] [smp:5:5] [ds:5:5:10] [async-threads:1]

Interactive Elixir (1.14.3) - press Ctrl+C to exit (type h() ENTER for help)
iex(api@127.0.0.1)1>

# Connect to a running Web node
❯ docker exec -it firezone-web-1 bin/web remote
Erlang/OTP 25 [erts-13.1.4] [source] [64-bit] [smp:5:5] [ds:5:5:10] [async-threads:1]

Interactive Elixir (1.14.3) - press Ctrl+C to exit (type h() ENTER for help)
iex(web@127.0.0.1)1>

From iex shell you can run any Elixir code, for example you can emulate a full flow using process messages, just keep in mind that you need to run seeds before executing this example:

[gateway | _rest_gateways] = Domain.Repo.all(Domain.Gateways.Gateway)
:ok = Domain.Gateways.connect_gateway(gateway)

[relay | _rest_relays] = Domain.Repo.all(Domain.Relays.Relay)
relay_secret = Domain.Crypto.rand_string()
:ok = Domain.Relays.connect_relay(relay, relay_secret)

Now if you connect and list resources there will be one online because there is a relay and gateway online.

Some of the functions require authorization, here is how you can obtain a subject:

user_agent = "User-Agent: iOS/12.7 (iPhone) connlib/0.7.412"
remote_ip = {127, 0, 0, 1}

# For a client
{:ok, subject} = Domain.Auth.sign_in(client_token, user_agent, remote_ip)

# For an admin user
provider = Domain.Repo.get_by(Domain.Auth.Provider, adapter: :userpass)
identity = Domain.Repo.get_by(Domain.Auth.Identity, provider_id: provider.id, provider_identifier: "firezone@localhost")
subject = Domain.Auth.build_subject(identity, nil, user_agent, remote_ip)

Listing connected gateways, relays, devices for an account:

account_id = "c89bcc8c-9392-4dae-a40d-888aef6d28e0"

%{
  gateways: Domain.Gateways.Presence.list("gateways:#{account_id}"),
  relays: Domain.Relays.Presence.list("relays:#{account_id}"),
  devices: Domain.Devices.Presence.list("devices:#{account_id}"),
}

Connecting to a staging or production instances

We use Google Cloud Platform for all our staging and production infrastructure. You'll need access to this env to perform the commands below; to get and access you need to add yourself to project_owners in main.tf for each of the environments.

This is a danger zone so first of all, ALWAYS make sure on which environment your code is running:

❯ gcloud config get project
firezone-staging

Then you want to figure out which specific instance you want to connect to:

❯ gcloud compute instances list
NAME      ZONE        MACHINE_TYPE   PREEMPTIBLE  INTERNAL_IP  EXTERNAL_IP  STATUS
api-b02t  us-east1-d  n1-standard-1               10.128.0.22               RUNNING
api-srkp  us-east1-d  n1-standard-1               10.128.0.23               RUNNING
web-51wd  us-east1-d  n1-standard-1               10.128.0.21               RUNNING
web-6k3n  us-east1-d  n1-standard-1               10.128.0.20               RUNNING

SSH into the VM and enter remote Elixir shell:

❯ gcloud compute ssh api-b02t
No zone specified. Using zone [us-east1-d] for instance: [api-b02t].
...

  ########################[ Welcome ]########################
  #  You have logged in to the guest OS.                    #
  #  To access your containers use 'docker attach' command  #
  ###########################################################

andrew@api-b02t ~ $ docker ps --format json | jq '"\(.ID) \(.Image)"'
"1ab7d7c6878c - us-east1-docker.pkg.dev/firezone-staging/firezone/api:branch-andrew_deployment"

andrew@api-b02t ~ $ docker exec -it 1ab7d7c6878c bin/api remote
Erlang/OTP 25 [erts-13.1.4] [source] [64-bit] [smp:1:1] [ds:1:1:10] [async-threads:1] [jit]

Interactive Elixir (1.14.3) - press Ctrl+C to exit (type h() ENTER for help)
iex(api@api-b02t.us-east1-d.c.firezone-staging.internal)1>