hide the value of :password when the sasl logger is activated

Author: zookzook

lib/mongo/app.ex

@@ -7,6 +7,7 @@ defmodule Mongo.App do
     children = [
       worker(Mongo.IdServer, []),
       worker(Mongo.PBKDF2Cache, []),
+      worker(Mongo.PasswordSafe, []),
       worker(:gen_event, [local: Mongo.Events])
     ]
 

lib/mongo/auth.ex

@@ -1,6 +1,8 @@
 defmodule Mongo.Auth do
   @moduledoc false
 
+  alias Mongo.PasswordSafe
+
   def run(opts, state) do
 
     db           = opts[:database]
@@ -29,13 +31,13 @@ defmodule Mongo.Auth do
 
   defp setup(opts) do
     username = opts[:username]
-    password = opts[:password]
+    password = PasswordSafe.get_pasword()
     auth     = opts[:auth] || []
 
     auth =
       Enum.map(auth, fn opts ->
         username = opts[:username]
-        password = opts[:password]
+        password = PasswordSafe.get_pasword()
         {username, password}
       end)
 

lib/mongo/password_safe.ex

@@ -0,0 +1,34 @@
+defmodule Mongo.PasswordSafe do
+  @moduledoc """
+  The password safe stores the password while parsing the url and/or the options to avoid it from logging while the sasl logger is activated.
+  """
+
+  @me __MODULE__
+
+  use GenServer
+
+  def start_link(_ \\ nil) do
+    GenServer.start_link(__MODULE__, [], name: @me)
+  end
+
+  def set_password(password) do
+    GenServer.cast(@me, {:set, password})
+  end
+
+  def get_pasword() do
+    GenServer.call(@me, :get)
+  end
+
+  def init([]) do
+    {:ok, nil}
+  end
+
+  def handle_cast({:set, password}, data) do
+    {:noreply, password}
+  end
+
+  def handle_call(:get, _from, password) do
+    {:reply, password, password}
+  end
+
+end

lib/mongo/url_parser.ex

@@ -99,17 +99,18 @@ defmodule Mongo.UrlParser do
               |> Macro.underscore()
               |> String.to_atom()
 
-        value = decode_password(key, value)
+        value = decode_percent(key, value)
 
         Keyword.put(opts, @driver_option_map[key] || key, value)
     end
   end
 
   defp add_option(_other, acc), do: acc
 
-  defp decode_password(:username, value), do:  URI.decode_www_form(value)
-  defp decode_password(:password, value), do:  URI.decode_www_form(value)
-  defp decode_password(_other, value), do: value
+  defp decode_percent(:username, value), do:  URI.decode_www_form(value)
+  defp decode_percent(:password, value), do:  URI.decode_www_form(value)
+  defp decode_percent(_other, value), do: value
+
 
   defp parse_query_options(opts, %{"options" => options}) when is_binary(options) do
     options
@@ -159,6 +160,16 @@ defmodule Mongo.UrlParser do
     {:ok, hosts}
   end
 
+  defp hide_password(opts) do
+    case Keyword.get(opts, :password) do
+      nil -> opts
+      value ->
+        with :ok <- Mongo.PasswordSafe.set_password(value) do
+          Keyword.put(opts, :password, "*****")
+        end
+    end
+  end
+
   @spec parse_url(Keyword.t()) :: Keyword.t()
   def parse_url(opts) when is_list(opts) do
     with {url, opts} when is_binary(url) <- Keyword.pop(opts, :url),
@@ -172,6 +183,7 @@ defmodule Mongo.UrlParser do
     else
       _other -> opts
     end
+    |> hide_password()
   end
 
   def parse_url(opts), do: opts

test/mongo/password_safe_test.exs

@@ -0,0 +1,22 @@
+defmodule Mongo.PasswordSafeTest do
+  @moduledoc false
+
+  use ExUnit.Case, async: false
+  alias Mongo.UrlParser
+  alias Mongo.PasswordSafe
+
+  #
+  # When the sasl logger is activated like  `--logger-sasl-reports true` then the supervisor reports all parameters when it starts a process. So, the password should not
+  # used in the options
+  #
+  describe "parse_url and hide the password in options" do
+    test "encoded password" do
+      url = "mongodb://myDBReader:D1fficultP%[email protected]:27017/admin"
+      opts = UrlParser.parse_url([url: url])
+
+      assert "*****" == Keyword.get(opts, :password)
+      assert "D1fficultP@ssw0rd" == PasswordSafe.get_pasword()
+    end
+  end
+
+end

test/mongo/url_parser_test.exs

@@ -14,8 +14,8 @@ defmodule Mongo.UrlParserTest do
         "mongodb://user:[email protected]:27017,seed2.domain.com:27017,seed3.domain.com:27017/db_name?ssl=true&replicaSet=set-name&authSource=admin&maxPoolSize=5"
 
       assert UrlParser.parse_url(url: url) == [
+               password: "*****",
                username: "user",
-               password: "password",
                database: "db_name",
                pool_size: 5,
                auth_source: "admin",
@@ -49,8 +49,8 @@ defmodule Mongo.UrlParserTest do
     test "url srv with user" do
       assert UrlParser.parse_url(url: "mongodb+srv://user:[email protected]") ==
                [
+                 password: "*****",
                  username: "user",
-                 password: "password",
                  ssl: true,
                  auth_source: "thisDB",
                  set_name: "repl0",
@@ -73,18 +73,15 @@ defmodule Mongo.UrlParserTest do
       end
     end
 
-    test "encoded password" do
-
+    test "encoded user" do
       real_username = "@:/skøl:@/"
       real_password = "@æœ{}%e()}@"
 
       encoded_username = URI.encode_www_form(real_username)
       encoded_password = URI.encode_www_form(real_password)
       url = "mongodb://#{encoded_username}:#{encoded_password}@mymongodbserver:27017/admin"
       opts = UrlParser.parse_url(url: url)
-      password = Keyword.get(opts, :password)
       username = Keyword.get(opts, :username)
-      assert password == real_password
       assert username == real_username
     end