public void CorruptHeader_InvalidMessageSize()
{
MqttHeader inputHeader = new MqttHeader()
{
Duplicate = true,
Retain = false,
MessageSize = 268435455, // the max message size, which we will fudge later in the test
MessageType = MqttMessageType.Connect,
Qos = MqttQos.AtLeastOnce
};
MqttHeader outputHeader;
using (MemoryStream stream = new MemoryStream())
{
inputHeader.WriteTo(268435455, stream);
// fudge the header by making the last bit of the 4th message size byte a 1, therefore making the header
// invalid because the last bit of the 4th size byte should always be 0 (according to the spec). It's how
// we know to stop processing the header when reading a full message).
stream.Seek(4, SeekOrigin.Begin);
byte existingByte = (byte)stream.ReadByte();
stream.Seek(4, SeekOrigin.Begin);
stream.WriteByte((byte)(existingByte | 0xFF));
stream.Seek(0, SeekOrigin.Begin);
Assert.Throws<InvalidHeaderException>(() => outputHeader = new MqttHeader(stream));
}
}
public void HeaderRoundtrip()
{
MqttHeader inputHeader = new MqttHeader()
{
Duplicate = true,
Retain = false,
MessageSize = 1,
MessageType = MqttMessageType.Connect,
Qos = MqttQos.AtLeastOnce
};
MqttHeader outputHeader;
using (MemoryStream stream = new MemoryStream())
{
inputHeader.WriteTo(0, stream);
// the stream will be chock full-o-bytes, rewind it so we can read it back
stream.Seek(0, SeekOrigin.Begin);
outputHeader = new MqttHeader(stream);
}
Assert.Equal<bool>(inputHeader.Duplicate, outputHeader.Duplicate);
Assert.Equal<bool>(inputHeader.Retain, outputHeader.Retain);
Assert.Equal<MqttQos>(inputHeader.Qos, outputHeader.Qos);
Assert.Equal<MqttMessageType>(inputHeader.MessageType, outputHeader.MessageType);
}
