/// <summary>
/// Constructor
/// </summary>
/// <param name="connect">CONNECT message received from client</param>
public MqttMsgConnectEventArgs(MqttMsgConnect connect)
{
Message = connect;
}
/// <summary>
/// Parse bytes for a CONNECT message
/// </summary>
/// <param name="fixedHeaderFirstByte">First fixed header byte</param>
/// <param name="protocolVersion">MQTT Protocol Version</param>
/// <param name="channel">Channel connected to the broker</param>
/// <returns>CONNECT message instance</returns>
public static MqttMsgConnect Parse(byte fixedHeaderFirstByte, MqttProtocolVersion protocolVersion, IMqttNetworkChannel channel)
{
byte[] buffer;
int index = 0;
bool isUsernameFlag;
bool isPasswordFlag;
int length;
MqttMsgConnect msg = new MqttMsgConnect();
// get remaining length and allocate buffer
int remainingLength = DecodeVariableByte(channel);
buffer = new byte[remainingLength];
// read bytes from socket...
channel.Receive(buffer);
// protocol name
msg.ProtocolName = EncodeDecodeHelper.GetUTF8FromBuffer(buffer, ref index);
// [v3.1.1] wrong protocol name valid for 5.0 as well
if (!msg.ProtocolName.Equals(PROTOCOL_NAME_V3_1) && !msg.ProtocolName.Equals(PROTOCOL_NAME_V3_1_1))
{
throw new MqttClientException(MqttClientErrorCode.InvalidProtocolName);
}
// protocol version
msg.ProtocolVersion = (MqttProtocolVersion)buffer[index];
index += PROTOCOL_VERSION_SIZE;
// connect flags
// [v3.1.1] check lsb (reserved) must be 0
if (((msg.ProtocolVersion == MqttProtocolVersion.Version_3_1_1) || (msg.ProtocolVersion == MqttProtocolVersion.Version_5)) &&
((buffer[index] & RESERVED_FLAG_MASK) != 0x00))
{
throw new MqttClientException(MqttClientErrorCode.InvalidConnectFlags);
}
isUsernameFlag = (buffer[index] & USERNAME_FLAG_MASK) != 0x00;
isPasswordFlag = (buffer[index] & PASSWORD_FLAG_MASK) != 0x00;
msg.WillRetain = (buffer[index] & WILL_RETAIN_FLAG_MASK) != 0x00;
msg.WillQosLevel = (byte)((buffer[index] & WILL_QOS_FLAG_MASK) >> WILL_QOS_FLAG_OFFSET);
msg.WillFlag = (buffer[index] & WILL_FLAG_MASK) != 0x00;
msg.CleanSession = (buffer[index] & CLEAN_SESSION_FLAG_MASK) != 0x00;
index += CONNECT_FLAGS_SIZE;
// keep alive timer
msg.KeepAlivePeriod = (ushort)((buffer[index++] << 8) & 0xFF00);
msg.KeepAlivePeriod |= buffer[index++];
// In case of v5, we have properties encoded with length and type.
// This is different than in the v3.x protocols
if (msg.ProtocolVersion == MqttProtocolVersion.Version_5)
{
// size of the properties
int propSize = EncodeDecodeHelper.GetPropertySize(buffer, ref index);
propSize += index;
MqttProperty prop;
while (propSize > index)
{
prop = (MqttProperty)buffer[index++];
switch (prop)
{
case MqttProperty.AuthenticationMethod:
// UTF8 encoded
msg.AuthenticationMethod = EncodeDecodeHelper.GetUTF8FromBuffer(buffer, ref index);
break;
case MqttProperty.AuthenticationData:
// byte[]
length = ((buffer[index++] << 8) & 0xFF00);
length |= buffer[index++];
msg.AuthenticationData = new byte[length];
Array.Copy(buffer, index, msg.AuthenticationData, 0, length);
index += length;
break;
case MqttProperty.RequestProblemInformation:
// 1 byte
msg.RequestProblemInformation = buffer[index++] != 0;
break;
case MqttProperty.RequestResponseInformation:
// 1 byte
msg.RequestResponseInformation = buffer[index++] != 0;
break;
case MqttProperty.ReceiveMaximum:
// 2 bytes
msg.ReceiveMaximum = (ushort)(buffer[index++] << 8);
msg.ReceiveMaximum |= buffer[index++];
break;
case MqttProperty.TopicAliasMaximum:
// 2 bytes
msg.TopicAliasMaximum = (ushort)(buffer[index++] << 8);
msg.TopicAliasMaximum |= buffer[index++];
break;
case MqttProperty.UserProperty:
// UTF8 key value encoding, so 2 strings in a raw
string key = EncodeDecodeHelper.GetUTF8FromBuffer(buffer, ref index);
string value = EncodeDecodeHelper.GetUTF8FromBuffer(buffer, ref index);
msg.UserProperties.Add(new UserProperty(key, value));
break;
case MqttProperty.MaximumPacketSize:
// 4 bytes
msg.MaximumPacketSize = EncodeDecodeHelper.DecodeUint(buffer, ref index);
break;
case MqttProperty.SessionExpiryInterval:
// 4 bytes
msg.SessionExpiryInterval = EncodeDecodeHelper.DecodeUint(buffer, ref index);
break;
case MqttProperty.WillDelayInterval:
// 4 bytes
msg.WillDelayInterval = EncodeDecodeHelper.DecodeUint(buffer, ref index);
break;
default:
// non supported property
index = propSize;
break;
}
}
}
// client identifier [v3.1.1] it may be zero bytes long (empty string)
msg.ClientId = EncodeDecodeHelper.GetUTF8FromBuffer(buffer, ref index);
// [v3.1.1] if client identifier is zero bytes long, clean session must be true
if ((msg.ProtocolVersion == MqttProtocolVersion.Version_3_1_1) && (msg.ClientId.Length == 0) && (!msg.CleanSession))
{
throw new MqttClientException(MqttClientErrorCode.InvalidClientId);
}
// will topic and will message
if (msg.WillFlag)
{
msg.WillTopic = EncodeDecodeHelper.GetUTF8FromBuffer(buffer, ref index);
msg.WillMessage = EncodeDecodeHelper.GetUTF8FromBuffer(buffer, ref index);
}
// username
if (isUsernameFlag)
{
msg.Username = EncodeDecodeHelper.GetUTF8FromBuffer(buffer, ref index);
}
// password
if (isPasswordFlag)
{
msg.Password = EncodeDecodeHelper.GetUTF8FromBuffer(buffer, ref index);
}
return(msg);
}
