1 files changed, 135 insertions, 0 deletions
diff --git a/lib/pleroma/gun/conn.ex b/lib/pleroma/gun/conn.ex
new file mode 100644
index 000000000..a3f75a4bb
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+++ b/lib/pleroma/gun/conn.ex
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+# Pleroma: A lightweight social networking server
+# Copyright © 2017-2020 Pleroma Authors <https://pleroma.social/>
+# SPDX-License-Identifier: AGPL-3.0-only
+
+defmodule Pleroma.Gun.Conn do
+  alias Pleroma.Gun
+
+  require Logger
+
+  def open(%URI{} = uri, opts) do
+    pool_opts = Pleroma.Config.get([:connections_pool], [])
+
+    opts =
+      opts
+      |> Enum.into(%{})
+      |> Map.put_new(:await_up_timeout, pool_opts[:await_up_timeout] || 5_000)
+      |> Map.put_new(:supervise, false)
+      |> maybe_add_tls_opts(uri)
+
+    do_open(uri, opts)
+  end
+
+  defp maybe_add_tls_opts(opts, %URI{scheme: "http"}), do: opts
+
+  defp maybe_add_tls_opts(opts, %URI{scheme: "https"}) do
+    tls_opts = [
+      verify: :verify_peer,
+      cacertfile: CAStore.file_path(),
+      depth: 20,
+      reuse_sessions: false,
+      log_level: :warning,
+      customize_hostname_check: [match_fun: :public_key.pkix_verify_hostname_match_fun(:https)]
+    ]
+
+    tls_opts =
+      if Keyword.keyword?(opts[:tls_opts]) do
+        Keyword.merge(tls_opts, opts[:tls_opts])
+      else
+        tls_opts
+      end
+
+    Map.put(opts, :tls_opts, tls_opts)
+  end
+
+  defp do_open(uri, %{proxy: {proxy_host, proxy_port}} = opts) do
+    connect_opts =
+      uri
+      |> destination_opts()
+      |> add_http2_opts(uri.scheme, Map.get(opts, :tls_opts, []))
+
+    with open_opts <- Map.delete(opts, :tls_opts),
+         {:ok, conn} <- Gun.open(proxy_host, proxy_port, open_opts),
+         {:ok, _} <- Gun.await_up(conn, opts[:await_up_timeout]),
+         stream <- Gun.connect(conn, connect_opts),
+         {:response, :fin, 200, _} <- Gun.await(conn, stream) do
+      {:ok, conn}
+    else
+      error ->
+        Logger.warn(
+          "Opening proxied connection to #{compose_uri_log(uri)} failed with error #{
+            inspect(error)
+          }"
+        )
+
+        error
+    end
+  end
+
+  defp do_open(uri, %{proxy: {proxy_type, proxy_host, proxy_port}} = opts) do
+    version =
+      proxy_type
+      |> to_string()
+      |> String.last()
+      |> case do
+        "4" -> 4
+        _ -> 5
+      end
+
+    socks_opts =
+      uri
+      |> destination_opts()
+      |> add_http2_opts(uri.scheme, Map.get(opts, :tls_opts, []))
+      |> Map.put(:version, version)
+
+    opts =
+      opts
+      |> Map.put(:protocols, [:socks])
+      |> Map.put(:socks_opts, socks_opts)
+
+    with {:ok, conn} <- Gun.open(proxy_host, proxy_port, opts),
+         {:ok, _} <- Gun.await_up(conn, opts[:await_up_timeout]) do
+      {:ok, conn}
+    else
+      error ->
+        Logger.warn(
+          "Opening socks proxied connection to #{compose_uri_log(uri)} failed with error #{
+            inspect(error)
+          }"
+        )
+
+        error
+    end
+  end
+
+  defp do_open(%URI{host: host, port: port} = uri, opts) do
+    host = Pleroma.HTTP.AdapterHelper.parse_host(host)
+
+    with {:ok, conn} <- Gun.open(host, port, opts),
+         {:ok, _} <- Gun.await_up(conn, opts[:await_up_timeout]) do
+      {:ok, conn}
+    else
+      error ->
+        Logger.warn(
+          "Opening connection to #{compose_uri_log(uri)} failed with error #{inspect(error)}"
+        )
+
+        error
+    end
+  end
+
+  defp destination_opts(%URI{host: host, port: port}) do
+    host = Pleroma.HTTP.AdapterHelper.parse_host(host)
+    %{host: host, port: port}
+  end
+
+  defp add_http2_opts(opts, "https", tls_opts) do
+    Map.merge(opts, %{protocols: [:http2], transport: :tls, tls_opts: tls_opts})
+  end
+
+  defp add_http2_opts(opts, _, _), do: opts
+
+  def compose_uri_log(%URI{scheme: scheme, host: host, path: path}) do
+    "#{scheme}://#{host}#{path}"
+  end
+end