Enable cleartext plugin

lib/myxql.ex

@@ -23,6 +23,7 @@ defmodule MyXQL do
           | {:ping_timeout, timeout()}
           | {:prepare, :force_named | :named | :unnamed}
           | {:disconnect_on_error_codes, [atom()]}
+          | {:enable_cleartext_plugin, boolean()}
           | DBConnection.start_option()
 
   @type option() :: DBConnection.option()
@@ -100,6 +101,8 @@ defmodule MyXQL do
       will disconnect the connection. See "Disconnecting on Errors" section below for more
       information.
 
+    * `:enable_cleartext_plugin` - Set to `true` to send password as cleartext (default: `false`)
+
    The given options are passed down to DBConnection, some of the most commonly used ones are
    documented below:
 

lib/myxql/client.ex

@@ -25,7 +25,8 @@ defmodule MyXQL.Client do
       :socket_options,
       :max_packet_size,
       :charset,
-      :collation
+      :collation,
+      :enable_cleartext_plugin
     ]
 
     def new(opts) do
@@ -45,7 +46,8 @@ defmodule MyXQL.Client do
         socket_options:
           Keyword.merge([mode: :binary, packet: :raw, active: false], opts[:socket_options] || []),
         charset: Keyword.get(opts, :charset),
-        collation: Keyword.get(opts, :collation)
+        collation: Keyword.get(opts, :collation),
+        enable_cleartext_plugin: Keyword.get(opts, :enable_cleartext_plugin, false)
       }
     end
 
@@ -404,7 +406,10 @@ defmodule MyXQL.Client do
     initial_handshake(
       auth_plugin_name: initial_auth_plugin_name,
       auth_plugin_data: initial_auth_plugin_data
-    ) = initial_handshake
+    ) = case config.enable_cleartext_plugin do
+        true -> initial_handshake(initial_handshake, auth_plugin_name: "mysql_clear_password", auth_plugin_data: nil)
+        false -> initial_handshake
+    end
 
     auth_response = Auth.auth_response(config, initial_auth_plugin_name, initial_auth_plugin_data)
 

lib/myxql/protocol/auth.ex

@@ -33,6 +33,9 @@ defmodule MyXQL.Protocol.Auth do
       config.password == nil ->
         ""
 
+      auth_plugin_name == "mysql_clear_password" ->
+        config.password <> <<0>>
+
       auth_plugin_name == "mysql_native_password" ->
         mysql_native_password(config.password, initial_auth_plugin_data)
 

lib/myxql/protocol/types.ex

@@ -66,6 +66,8 @@ defmodule MyXQL.Protocol.Types do
     string
   end
 
+  def take_string_nul(""), do: {nil, ""}
+
   def take_string_nul(binary) do
     [string, rest] = :binary.split(binary, <<0>>)
     {string, rest}

test/myxql/client_test.exs

@@ -78,6 +78,23 @@ defmodule MyXQL.ClientTest do
       Client.com_quit(client)
     end
 
+    # mysql_clear_password
+
+    test "mysql_clear_password" do
+      opts = [username: "mysql_clear", password: "secret", enable_cleartext_plugin: true] ++ @opts
+      %{port: port} = start_cleartext_fake_server()
+      opts = Keyword.put(opts, :port, port)
+      assert {:ok, client} = Client.connect(opts)
+      Client.com_quit(client)
+    end
+
+    test "mysql_clear_password (bad password)" do
+      opts = [username: "mysql_clear", password: "bad", enable_cleartext_plugin: true] ++ @opts
+      %{port: port} = start_cleartext_fake_server()
+      opts = Keyword.put(opts, :port, port)
+      {:error, err_packet(message: "Access denied" <> _)} = Client.connect(opts)
+    end
+
     # sha256_password
 
     @tag sha256_password: true, public_key_exchange: true
@@ -447,4 +464,60 @@ defmodule MyXQL.ClientTest do
 
     %{pid: pid, port: port}
   end
+
+
+  defp start_cleartext_fake_server() do
+    start_fake_server(fn %{accept_socket: sock} ->
+      initial_handshake =
+        <<74, 0, 0, 0, 10, 56, 46, 48, 46, 51, 53, 0, 127, 24, 4, 0, 93, 42, 61, 27, 60,
+          38, 85, 12, 0, 255, 255, 255, 2, 0, 255, 223, 21, 0, 0, 0, 0, 0, 0, 0, 0, 0,
+          0, 39, 48, 10, 117, 54, 65, 74, 37, 125, 121, 93, 6, 0, 109, 121, 115, 113,
+          108, 95, 110, 97, 116, 105, 118, 101, 95, 112, 97, 115, 115, 119, 111, 114,
+          100, 0>>
+
+      client_auth_response_1 =
+        <<84, 0, 0, 1, 10, 162, 11, 0, 255, 255, 255, 0, 45, 0, 0, 0, 0, 0, 0, 0, 0, 0,
+          0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 109, 121, 115, 113, 108, 95, 99,
+          108, 101, 97, 114, 0, 7, 115, 101, 99, 114, 101, 116, 0, 109, 121, 120, 113,
+          108, 95, 116, 101, 115, 116, 0, 109, 121, 115, 113, 108, 95, 99, 108, 101,
+          97, 114, 95, 112, 97, 115, 115, 119, 111, 114, 100, 0>>
+
+      auth_response_1 =
+        <<22, 0, 0, 2, 254, 109, 121, 115, 113, 108, 95, 99, 108, 101, 97, 114, 95, 112,
+          97, 115, 115, 119, 111, 114, 100, 0>>
+
+      client_auth_response_2 =
+        <<7, 0, 0, 3, 115, 101, 99, 114, 101, 116, 0>>
+
+      auth_response_2 =
+        <<7, 0, 0, 4, 0, 0, 0, 2, 0, 0, 0>>
+
+      client_quit = <<1, 0, 0, 0, 1>>
+
+      close = <<7, 0, 0, 6, 0, 0, 0, 2, 0, 0, 0>>
+
+      auth_response_invalid =
+        <<83, 0, 0, 1, 255, 21, 4, 35, 50, 56, 48, 48, 48, 65, 99, 99, 101, 115, 115,
+          32, 100, 101, 110, 105, 101, 100, 32, 102, 111, 114, 32, 117, 115, 101, 114,
+          32, 39, 100, 101, 102, 97, 117, 108, 116, 95, 97, 117, 116, 104, 39, 64, 39,
+          49, 57, 50, 46, 49, 54, 56, 46, 54, 53, 46, 49, 39, 32, 40, 117, 115, 105,
+          110, 103, 32, 112, 97, 115, 115, 119, 111, 114, 100, 58, 32, 89, 69, 83, 41>>
+
+      :gen_tcp.send(sock, initial_handshake)
+
+      case :gen_tcp.recv(sock, 0) do
+        {:ok, ^client_auth_response_1} ->
+          :gen_tcp.send(sock, auth_response_1)
+          {:ok, ^client_auth_response_2} = :gen_tcp.recv(sock, 0)
+          :gen_tcp.send(sock, auth_response_2)
+
+          {:ok, ^client_quit} = :gen_tcp.recv(sock, 0)
+
+          :gen_tcp.send(sock, close)
+
+        {:ok, _other} ->
+          :gen_tcp.send(sock, auth_response_invalid)
+      end
+    end)
+  end
 end