diff --git a/lib/pleroma/plugs/ensure_public_or_authenticated_plug.ex b/lib/pleroma/plugs/ensure_public_or_authenticated_plug.ex
new file mode 100644
index 000000000..317fd5445
--- /dev/null
+++ b/lib/pleroma/plugs/ensure_public_or_authenticated_plug.ex
@@ -0,0 +1,31 @@
+# Pleroma: A lightweight social networking server
+# Copyright © 2017-2019 Pleroma Authors <https://pleroma.social/>
+# SPDX-License-Identifier: AGPL-3.0-only
+
+defmodule Pleroma.Plugs.EnsurePublicOrAuthenticatedPlug do
+  import Plug.Conn
+  alias Pleroma.Config
+  alias Pleroma.User
+
+  def init(options) do
+    options
+  end
+
+  def call(conn, _) do
+    public? = Config.get!([:instance, :public])
+
+    case {public?, conn} do
+      {true, _} ->
+        conn
+
+      {false, %{assigns: %{user: %User{}}}} ->
+        conn
+
+      {false, _} ->
+        conn
+        |> put_resp_content_type("application/json")
+        |> send_resp(403, Jason.encode!(%{error: "This resource requires authentication."}))
+        |> halt
+    end
+  end
+end
diff --git a/test/plugs/ensure_public_or_authenticated_plug_test.exs b/test/plugs/ensure_public_or_authenticated_plug_test.exs
new file mode 100644
index 000000000..ce5d77ff7
--- /dev/null
+++ b/test/plugs/ensure_public_or_authenticated_plug_test.exs
@@ -0,0 +1,55 @@
+# Pleroma: A lightweight social networking server
+# Copyright © 2017-2018 Pleroma Authors <https://pleroma.social/>
+# SPDX-License-Identifier: AGPL-3.0-only
+
+defmodule Pleroma.Plugs.EnsurePublicOrAuthenticatedPlugTest do
+  use Pleroma.Web.ConnCase, async: true
+
+  alias Pleroma.Config
+  alias Pleroma.Plugs.EnsurePublicOrAuthenticatedPlug
+  alias Pleroma.User
+
+  test "it halts if not public and no user is assigned", %{conn: conn} do
+    set_public_to(false)
+
+    conn =
+      conn
+      |> EnsurePublicOrAuthenticatedPlug.call(%{})
+
+    assert conn.status == 403
+    assert conn.halted == true
+  end
+
+  test "it continues if public", %{conn: conn} do
+    set_public_to(true)
+
+    ret_conn =
+      conn
+      |> EnsurePublicOrAuthenticatedPlug.call(%{})
+
+    assert ret_conn == conn
+  end
+
+  test "it continues if a user is assigned, even if not public", %{conn: conn} do
+    set_public_to(false)
+
+    conn =
+      conn
+      |> assign(:user, %User{})
+
+    ret_conn =
+      conn
+      |> EnsurePublicOrAuthenticatedPlug.call(%{})
+
+    assert ret_conn == conn
+  end
+
+  defp set_public_to(value) do
+    orig = Config.get!([:instance, :public])
+    Config.put([:instance, :public], value)
+
+    on_exit(fn ->
+      Config.put([:instance, :public], orig)
+    end)
+  end
+end