131 lines
3.7 KiB
Elixir
131 lines
3.7 KiB
Elixir
# Pleroma: A lightweight social networking server
|
|
# Copyright © 2017-2019 Pleroma Authors <https://pleroma.social/>
|
|
# SPDX-License-Identifier: AGPL-3.0-only
|
|
|
|
defmodule Pleroma.Plugs.RateLimiter do
|
|
@moduledoc """
|
|
|
|
## Configuration
|
|
|
|
A keyword list of rate limiters where a key is a limiter name and value is the limiter configuration. The basic configuration is a tuple where:
|
|
|
|
* The first element: `scale` (Integer). The time scale in milliseconds.
|
|
* The second element: `limit` (Integer). How many requests to limit in the time scale provided.
|
|
|
|
It is also possible to have different limits for unauthenticated and authenticated users: the keyword value must be a list of two tuples where the first one is a config for unauthenticated users and the second one is for authenticated.
|
|
|
|
To disable a limiter set its value to `nil`.
|
|
|
|
### Example
|
|
|
|
config :pleroma, :rate_limit,
|
|
one: {1000, 10},
|
|
two: [{10_000, 10}, {10_000, 50}],
|
|
foobar: nil
|
|
|
|
Here we have three limiters:
|
|
|
|
* `one` which is not over 10req/1s
|
|
* `two` which has two limits: 10req/10s for unauthenticated users and 50req/10s for authenticated users
|
|
* `foobar` which is disabled
|
|
|
|
## Usage
|
|
|
|
AllowedSyntax:
|
|
|
|
plug(Pleroma.Plugs.RateLimiter, :limiter_name)
|
|
plug(Pleroma.Plugs.RateLimiter, {:limiter_name, options})
|
|
|
|
Allowed options:
|
|
|
|
* `bucket_name` overrides bucket name (e.g. to have a separate limit for a set of actions)
|
|
* `params` appends values of specified request params (e.g. ["id"]) to bucket name
|
|
|
|
Inside a controller:
|
|
|
|
plug(Pleroma.Plugs.RateLimiter, :one when action == :one)
|
|
plug(Pleroma.Plugs.RateLimiter, :two when action in [:two, :three])
|
|
|
|
plug(
|
|
Pleroma.Plugs.RateLimiter,
|
|
{:status_id_action, bucket_name: "status_id_action:fav_unfav", params: ["id"]}
|
|
when action in ~w(fav_status unfav_status)a
|
|
)
|
|
|
|
or inside a router pipeline:
|
|
|
|
pipeline :api do
|
|
...
|
|
plug(Pleroma.Plugs.RateLimiter, :one)
|
|
...
|
|
end
|
|
"""
|
|
import Pleroma.Web.TranslationHelpers
|
|
import Plug.Conn
|
|
|
|
alias Pleroma.User
|
|
|
|
def init(limiter_name) when is_atom(limiter_name) do
|
|
init({limiter_name, []})
|
|
end
|
|
|
|
def init({limiter_name, opts}) do
|
|
case Pleroma.Config.get([:rate_limit, limiter_name]) do
|
|
nil -> nil
|
|
config -> {limiter_name, config, opts}
|
|
end
|
|
end
|
|
|
|
# Do not limit if there is no limiter configuration
|
|
def call(conn, nil), do: conn
|
|
|
|
def call(conn, settings) do
|
|
case check_rate(conn, settings) do
|
|
{:ok, _count} ->
|
|
conn
|
|
|
|
{:error, _count} ->
|
|
render_throttled_error(conn)
|
|
end
|
|
end
|
|
|
|
defp bucket_name(conn, limiter_name, opts) do
|
|
bucket_name = opts[:bucket_name] || limiter_name
|
|
|
|
if params_names = opts[:params] do
|
|
params_values = for p <- Enum.sort(params_names), do: conn.params[p]
|
|
Enum.join([bucket_name] ++ params_values, ":")
|
|
else
|
|
bucket_name
|
|
end
|
|
end
|
|
|
|
defp check_rate(
|
|
%{assigns: %{user: %User{id: user_id}}} = conn,
|
|
{limiter_name, [_, {scale, limit}], opts}
|
|
) do
|
|
bucket_name = bucket_name(conn, limiter_name, opts)
|
|
ExRated.check_rate("#{bucket_name}:#{user_id}", scale, limit)
|
|
end
|
|
|
|
defp check_rate(conn, {limiter_name, [{scale, limit} | _], opts}) do
|
|
bucket_name = bucket_name(conn, limiter_name, opts)
|
|
ExRated.check_rate("#{bucket_name}:#{ip(conn)}", scale, limit)
|
|
end
|
|
|
|
defp check_rate(conn, {limiter_name, {scale, limit}, opts}) do
|
|
check_rate(conn, {limiter_name, [{scale, limit}, {scale, limit}], opts})
|
|
end
|
|
|
|
def ip(%{remote_ip: remote_ip}) do
|
|
remote_ip
|
|
|> Tuple.to_list()
|
|
|> Enum.join(".")
|
|
end
|
|
|
|
defp render_throttled_error(conn) do
|
|
conn
|
|
|> render_error(:too_many_requests, "Throttled")
|
|
|> halt()
|
|
end
|
|
end
|