Turn on markup normalisation by default
[akkoma] / lib / pleroma / web / activity_pub / mrf.ex
index 5e5361082755d11f3036d678d0f6881564b15433..064ffc527adef1b085a334255ad3897b32b8f2e5 100644 (file)
 # Pleroma: A lightweight social networking server
-# Copyright © 2017-2020 Pleroma Authors <https://pleroma.social/>
+# Copyright © 2017-2021 Pleroma Authors <https://pleroma.social/>
 # SPDX-License-Identifier: AGPL-3.0-only
 
 defmodule Pleroma.Web.ActivityPub.MRF do
-  @callback filter(Map.t()) :: {:ok | :reject, Map.t()}
+  require Logger
+
+  @behaviour Pleroma.Web.ActivityPub.MRF.PipelineFiltering
+
+  @mrf_config_descriptions [
+    %{
+      group: :pleroma,
+      key: :mrf,
+      tab: :mrf,
+      label: "MRF",
+      type: :group,
+      description: "General MRF settings",
+      children: [
+        %{
+          key: :policies,
+          type: [:module, {:list, :module}],
+          description:
+            "A list of MRF policies enabled. Module names are shortened (removed leading `Pleroma.Web.ActivityPub.MRF.` part), but on adding custom module you need to use full name.",
+          suggestions: {:list_behaviour_implementations, Pleroma.Web.ActivityPub.MRF.Policy}
+        },
+        %{
+          key: :transparency,
+          label: "MRF transparency",
+          type: :boolean,
+          description:
+            "Make the content of your Message Rewrite Facility settings public (via nodeinfo)"
+        },
+        %{
+          key: :transparency_exclusions,
+          label: "MRF transparency exclusions",
+          type: {:list, :tuple},
+          key_placeholder: "instance",
+          value_placeholder: "reason",
+          description:
+            "Exclude specific instance names from MRF transparency. The use of the exclusions feature will be disclosed in nodeinfo as a boolean value. You can also provide a reason for excluding these instance names. The instances and reasons won't be publicly disclosed.",
+          suggestions: [
+            "exclusion.com"
+          ]
+        },
+        %{
+          key: :transparency_obfuscate_domains,
+          label: "MRF domain obfuscation",
+          type: {:list, :string},
+          description:
+            "Obfuscate domains in MRF transparency. This is useful if the domain you're blocking contains words you don't want displayed, but still want to disclose the MRF settings.",
+          suggestions: [
+            "badword.com"
+          ]
+        }
+      ]
+    }
+  ]
+
+  @default_description %{
+    label: "",
+    description: ""
+  }
+
+  @required_description_keys [:key, :related_policy]
+
+  def filter_one(policy, message) do
+    should_plug_history? =
+      if function_exported?(policy, :history_awareness, 0) do
+        policy.history_awareness()
+      else
+        :manual
+      end
+      |> Kernel.==(:auto)
+
+    if not should_plug_history? do
+      policy.filter(message)
+    else
+      main_result = policy.filter(message)
+
+      with {_, {:ok, main_message}} <- {:main, main_result},
+           {_,
+            %{
+              "formerRepresentations" => %{
+                "orderedItems" => [_ | _]
+              }
+            }} = {_, object} <- {:object, message["object"]},
+           {_, {:ok, new_history}} <-
+             {:history,
+              Pleroma.Object.Updater.for_each_history_item(
+                object["formerRepresentations"],
+                object,
+                fn item ->
+                  with {:ok, filtered} <- policy.filter(Map.put(message, "object", item)) do
+                    {:ok, filtered["object"]}
+                  else
+                    e -> e
+                  end
+                end
+              )} do
+        {:ok, put_in(main_message, ["object", "formerRepresentations"], new_history)}
+      else
+        {:main, _} -> main_result
+        {:object, _} -> main_result
+        {:history, e} -> e
+      end
+    end
+  end
 
   def filter(policies, %{} = message) do
     policies
     |> Enum.reduce({:ok, message}, fn
-      policy, {:ok, message} -> policy.filter(message)
+      policy, {:ok, message} -> filter_one(policy, message)
       _, error -> error
     end)
   end
 
   def filter(%{} = object), do: get_policies() |> filter(object)
 
+  @impl true
   def pipeline_filter(%{} = message, meta) do
     object = meta[:object_data]
     ap_id = message["object"]
@@ -34,16 +136,34 @@ defmodule Pleroma.Web.ActivityPub.MRF do
   end
 
   def get_policies do
-    Pleroma.Config.get([:mrf, :policies], []) |> get_policies()
+    Pleroma.Config.get([:mrf, :policies], [])
+    |> get_policies()
+    |> Enum.concat([
+      Pleroma.Web.ActivityPub.MRF.HashtagPolicy,
+      Pleroma.Web.ActivityPub.MRF.InlineQuotePolicy,
+      Pleroma.Web.ActivityPub.MRF.NormalizeMarkup
+    ])
+    |> Enum.uniq()
   end
 
   defp get_policies(policy) when is_atom(policy), do: [policy]
   defp get_policies(policies) when is_list(policies), do: policies
   defp get_policies(_), do: []
 
+  # Matches the following:
+  # - https://baddomain.net
+  # - https://extra.baddomain.net/
+  # Does NOT match the following:
+  # - https://maybebaddomain.net/
+  def subdomain_regex("*." <> domain), do: subdomain_regex(domain)
+
+  def subdomain_regex(domain) do
+    ~r/^(.+\.)?#{Regex.escape(domain)}$/i
+  end
+
   @spec subdomains_regex([String.t()]) :: [Regex.t()]
   def subdomains_regex(domains) when is_list(domains) do
-    for domain <- domains, do: ~r(^#{String.replace(domain, "*.", "(.*\\.)*")}$)i
+    Enum.map(domains, &subdomain_regex/1)
   end
 
   @spec subdomain_match?([Regex.t()], String.t()) :: boolean()
@@ -51,7 +171,10 @@ defmodule Pleroma.Web.ActivityPub.MRF do
     Enum.any?(domains, fn domain -> Regex.match?(domain, host) end)
   end
 
-  @callback describe() :: {:ok | :error, Map.t()}
+  @spec instance_list_from_tuples([{String.t(), String.t()}]) :: [String.t()]
+  def instance_list_from_tuples(list) do
+    Enum.map(list, fn {instance, _} -> instance end)
+  end
 
   def describe(policies) do
     {:ok, policy_configs} =
@@ -82,4 +205,39 @@ defmodule Pleroma.Web.ActivityPub.MRF do
   end
 
   def describe, do: get_policies() |> describe()
+
+  def config_descriptions do
+    Pleroma.Web.ActivityPub.MRF.Policy
+    |> Pleroma.Docs.Generator.list_behaviour_implementations()
+    |> config_descriptions()
+  end
+
+  def config_descriptions(policies) do
+    Enum.reduce(policies, @mrf_config_descriptions, fn policy, acc ->
+      if function_exported?(policy, :config_description, 0) do
+        description =
+          @default_description
+          |> Map.merge(policy.config_description)
+          |> Map.put(:group, :pleroma)
+          |> Map.put(:tab, :mrf)
+          |> Map.put(:type, :group)
+
+        if Enum.all?(@required_description_keys, &Map.has_key?(description, &1)) do
+          [description | acc]
+        else
+          Logger.warn(
+            "#{policy} config description doesn't have one or all required keys #{inspect(@required_description_keys)}"
+          )
+
+          acc
+        end
+      else
+        Logger.debug(
+          "#{policy} is excluded from config descriptions, because does not implement `config_description/0` method."
+        )
+
+        acc
+      end
+    end)
+  end
 end