Fix wrong password handling (string -> byte[])

Source/MQTTnet.Server/Mqtt/MqttConnectionValidator.cs

 using System;
+using System.Text;
 using System.Threading.Tasks;
 using IronPython.Runtime;
 using Microsoft.Extensions.Logging;
@@ -22,6 +23,12 @@ namespace MQTTnet.Server.Mqtt
         {
             try
             {
+                string passwordString = null;
+                if (context.Password != null)
+                {
+                    passwordString = Encoding.UTF8.GetString(context.Password);
+                }
+
                 var pythonContext = new PythonDictionary
                 {
                     { "client_id", context.ClientId },
@@ -29,6 +36,7 @@ namespace MQTTnet.Server.Mqtt
                     { "is_secure_connection", context.IsSecureConnection },
                     { "username", context.Username },
                     { "password", context.Password },
+                    { "password_string", passwordString },
                     { "result", PythonConvert.Pythonfy(context.ReturnCode) }
                 };
 

Source/MQTTnet.Server/Scripts/00_sample.py

@@ -29,7 +29,7 @@ def on_validate_client_connection(context):
         context["result"] = "connection_refused_not_authorized"
         return
 
-    if context["password"] != "secret":
+    if context["password_string"] != "secret":
         context["result"] = "connection_refused_not_authorized"
 
     print(context)

Source/MQTTnet/Client/Options/IMqttClientCredentials.cs

@@ -2,7 +2,7 @@
 {
     public interface IMqttClientCredentials
     {
-        string Password { get; }
         string Username { get; }
+        byte[] Password { get; }
     }
 }
\ No newline at end of file

Source/MQTTnet/Client/Options/MqttClientCredentials.cs

@@ -4,6 +4,6 @@
     {
         public string Username { get; set; }
 
-        public string Password { get; set; }
+        public byte[] Password { get; set; }
     }
 }

Source/MQTTnet/Client/Options/MqttClientOptionsBuilder.cs

 using System;
 using System.Linq;
+using System.Text;
 using MQTTnet.Client.ExtendedAuthenticationExchange;
 using MQTTnet.Formatter;
 
@@ -116,6 +117,18 @@ namespace MQTTnet.Client.Options
         }
 
         public MqttClientOptionsBuilder WithCredentials(string username, string password = null)
+        {
+            byte[] passwordBuffer = null;
+
+            if (password != null)
+            {
+                passwordBuffer = Encoding.UTF8.GetBytes(password);
+            }
+
+            return WithCredentials(username, passwordBuffer);
+        }
+
+        public MqttClientOptionsBuilder WithCredentials(string username, byte[] password = null)
         {
             _options.Credentials = new MqttClientCredentials
             {

Source/MQTTnet/Formatter/V3/MqttV310PacketFormatter.cs

@@ -293,7 +293,7 @@ namespace MQTTnet.Formatter.V3
 
             if (passwordFlag)
             {
-                packet.Password = body.ReadStringWithLengthPrefix();
+                packet.Password = body.ReadWithLengthPrefix();
             }
 
             ValidateConnectPacket(packet);

Source/MQTTnet/Formatter/V5/MqttV500PacketDecoder.cs

@@ -208,7 +208,7 @@ namespace MQTTnet.Formatter.V5
 
             if (passwordFlag)
             {
-                packet.Password = body.ReadStringWithLengthPrefix();
+                packet.Password = body.ReadWithLengthPrefix();
             }
 
             return packet;

Source/MQTTnet/Packets/MqttConnectPacket.cs

@@ -6,7 +6,7 @@
 
         public string Username { get; set; }
 
-        public string Password { get; set; }
+        public byte[] Password { get; set; }
 
         public ushort KeepAlivePeriod { get; set; }
 
@@ -23,13 +23,14 @@
 
         public override string ToString()
         {
-            var password = Password;
-            if (!string.IsNullOrEmpty(password))
+            var passwordText = string.Empty;
+
+            if (Password != null)
             {
-                password = "****";
+                passwordText = "****";
             }
 
-            return string.Concat("Connect: [ClientId=", ClientId, "] [Username=", Username, "] [Password=", password, "] [KeepAlivePeriod=", KeepAlivePeriod, "] [CleanSession=", CleanSession, "]");
+            return string.Concat("Connect: [ClientId=", ClientId, "] [Username=", Username, "] [Password=", passwordText, "] [KeepAlivePeriod=", KeepAlivePeriod, "] [CleanSession=", CleanSession, "]");
         }
     }
 }

Source/MQTTnet/Server/MqttConnectionValidatorContext.cs

-using MQTTnet.Protocol;
+using System.Text;
+using MQTTnet.Protocol;
 
 namespace MQTTnet.Server
 {
     public class MqttConnectionValidatorContext
     {
-        public MqttConnectionValidatorContext(string clientId, string username, string password, MqttApplicationMessage willMessage, string endpoint, bool isSecureConnection)
+        public MqttConnectionValidatorContext(string clientId, string username, byte[] password, MqttApplicationMessage willMessage, string endpoint, bool isSecureConnection)
         {
             ClientId = clientId;
             Username = username;
@@ -18,7 +19,7 @@ namespace MQTTnet.Server
 
         public string Username { get; }
 
-        public string Password { get; }
+        public byte[] Password { get; }
 
         public MqttApplicationMessage WillMessage { get; }
 

Tests/MQTTnet.Core.Tests/MqttPacketSerializer_Tests.cs

@@ -23,7 +23,7 @@ namespace MQTTnet.Tests
             var p = new MqttConnectPacket
             {
                 ClientId = "XYZ",
-                Password = "PASS",
+                Password = Encoding.UTF8.GetBytes("PASS"),
                 Username = "USER",
                 KeepAlivePeriod = 123,
                 CleanSession = true
@@ -38,7 +38,7 @@ namespace MQTTnet.Tests
             var p = new MqttConnectPacket
             {
                 ClientId = "XYZ",
-                Password = "PASS",
+                Password = Encoding.UTF8.GetBytes("PASS"),
                 Username = "USER",
                 KeepAlivePeriod = 123,
                 CleanSession = true
@@ -53,7 +53,7 @@ namespace MQTTnet.Tests
             var p = new MqttConnectPacket
             {
                 ClientId = "XYZ",
-                Password = "PASS",
+                Password = Encoding.UTF8.GetBytes("PASS"),
                 Username = "USER",
                 KeepAlivePeriod = 123,
                 CleanSession = true,
@@ -75,7 +75,7 @@ namespace MQTTnet.Tests
             var p = new MqttConnectPacket
             {
                 ClientId = "XYZ",
-                Password = "PASS",
+                Password = Encoding.UTF8.GetBytes("PASS"),
                 Username = "USER",
                 KeepAlivePeriod = 123,
                 CleanSession = true
@@ -90,7 +90,7 @@ namespace MQTTnet.Tests
             var p = new MqttConnectPacket
             {
                 ClientId = "XYZ",
-                Password = "PASS",
+                Password = Encoding.UTF8.GetBytes("PASS"),
                 Username = "USER",
                 KeepAlivePeriod = 123,
                 CleanSession = true,

Tests/MQTTnet.TestApp.NetCore/ManagedClientTest.cs

@@ -62,7 +62,7 @@ namespace MQTTnet.TestApp.NetCore
 
         public class RandomPassword : IMqttClientCredentials
         {
-            public string Password => Guid.NewGuid().ToString();
+            public byte[] Password => Guid.NewGuid().ToByteArray();
 
             public string Username => "the_static_user";
         }

Tests/MQTTnet.TestApp.NetCore/ServerTest.cs

@@ -28,7 +28,8 @@ namespace MQTTnet.TestApp.NetCore
                     {
                         if (p.ClientId == "SpecialClient")
                         {
-                            if (p.Username != "USER" || p.Password != "PASS")
+                            var password = Encoding.UTF8.GetString(p.Password);
+                            if (p.Username != "USER" || password != "PASS")
                             {
                                 p.ReturnCode = MqttConnectReturnCode.ConnectionRefusedBadUsernameOrPassword;
                             }

Tests/MQTTnet.TestApp.UniversalWindows/MainPage.xaml.cs

@@ -138,7 +138,7 @@ namespace MQTTnet.TestApp.UniversalWindows
                 options.Credentials = new MqttClientCredentials
                 {
                     Username = User.Text,
-                    Password = Password.Text
+                    Password = Encoding.UTF8.GetBytes(Password.Text)
                 };
             }
             
@@ -539,7 +539,7 @@ namespace MQTTnet.TestApp.UniversalWindows
                     //...
                 }
                 
-                client.UseApplicationMessageReceivedHandler(Handler);
+                client.UseApplicationMessageReceivedHandler(e => Handler(e));
 
                 // Subscribe after connect
 
@@ -601,7 +601,7 @@ namespace MQTTnet.TestApp.UniversalWindows
                         Credentials = new MqttClientCredentials
                         {
                             Username = "bud",
-                            Password = "%spencer%"
+                            Password = Encoding.UTF8.GetBytes("%spencer%")
                         },
                         ChannelOptions = new MqttClientTcpOptions
                         {
@@ -633,7 +633,9 @@ namespace MQTTnet.TestApp.UniversalWindows
                         return;
                     }
 
-                    if (c.Password != "mySecretPassword")
+                    var password = Encoding.UTF8.GetString(c.Password);
+
+                    if (password != "mySecretPassword")
                     {
                         c.ReturnCode = MqttConnectReturnCode.ConnectionRefusedBadUsernameOrPassword;
                         return;
@@ -717,7 +719,8 @@ namespace MQTTnet.TestApp.UniversalWindows
                             return;
                         }
 
-                        if (c.Password != "mySecretPassword")
+                        var password = Encoding.UTF8.GetString(c.Password);
+                        if (password != "mySecretPassword")
                         {
                             c.ReturnCode = MqttConnectReturnCode.ConnectionRefusedBadUsernameOrPassword;
                             return;