/// <summary>
/// Initializes a new instance of the Interface class using the specified
/// parameters.
/// </summary>
/// <param name="nic">The network interface card (NIC) this interface
/// represents.</param>
/// <param name="name">A unique name (such as eth0) for identifing the
/// interface.</param>
/// <param name="ipAddress">The IPv4 address to associate with this
/// interface.</param>
/// <param name="netmask">The subnetmask to assign to this interface.</param>
/// <param name="gateway">The IPv4 address of the default gateway to
/// configure this interface with.</param>
/// <exception cref="ArgumentNullException">Thrown if any of the arguments
/// is null.</exception>
public Interface(Nic nic, string name, IpAddress ipAddress, IpAddress netmask,
IpAddress gateway = null) {
Init(nic, name, ipAddress, netmask, gateway);
}
/// <summary>
/// Initializes the interface.
/// </summary>
/// <param name="nic">The network interface card (NIC) this interface
/// represents.</param>
/// <param name="name">A unique name (such as eth0) for identifing the
/// interface.</param>
/// <param name="ipAddress">The IPv4 address to associate with this
/// interface.</param>
/// <param name="netmask">The subnetmask to assign to this interface.</param>
/// <param name="gateway">The IPv4 address of the default gateway to
/// configure this interface with.</param>
void Init(Nic nic, string name, IpAddress ipAddress, IpAddress netmask,
IpAddress gateway) {
nic.ThrowIfNull("nic");
name.ThrowIfNull("name");
ipAddress.ThrowIfNull("ipAddress");
netmask.ThrowIfNull("netmask");
Nic = nic;
Name = name;
IpAddress = ipAddress;
Netmask = netmask;
Gateway = gateway;
Nic.Interrupt += OnInterrupt;
}
/// <summary>
/// Deserializes an IpPacket instance from the specified sequence of
/// bytes.
/// </summary>
/// <param name="data">The sequence of bytes to deserialize an IpPacket
/// object from.</param>
/// <returns>A deserialized IpPacket object.</returns>
/// <exception cref="ArgumentNullException">Thrown if the data argument is
/// null.</exception>
/// <exception cref="SerializationException">Thrown if the IP packet could
/// not be deserialized from the specified byte array.</exception>
public static IpPacket Deserialize(byte[] data) {
data.ThrowIfNull("data");
using (var ms = new MemoryStream(data)) {
using (var reader = new BinaryReader(ms)) {
var vi = reader.ReadByte();
var version = (IpVersion)(vi & 0x0F);
byte ihl = (byte) (vi >> 4), dscp = reader.ReadByte();
ushort totalLength = reader.ReadUInt16(),
identification = reader.ReadUInt16(), ffo = reader.ReadUInt16();
var flags = (IpFlag) (ffo & 0x07);
var fragmentOffset = (ushort) (ffo >> 3);
var ttl = reader.ReadByte();
var type = (IpProtocol) reader.ReadByte();
var checksum = reader.ReadUInt16();
IpAddress src = new IpAddress(reader.ReadBytes(4)),
dst = new IpAddress(reader.ReadBytes(4));
var packet = new IpPacket(version, ihl, dscp, totalLength,
identification, flags, fragmentOffset, ttl, type, checksum,
src, dst);
// Computing the checksum should yield a value of 0 unless errors are
// detected.
if (ComputeChecksum(packet, true) != 0)
throw new SerializationException("The IPv4 header is corrupted.");
// If no errors have been detected, read the data section.
packet.Data = reader.ReadBytes(totalLength - 20);
return packet;
}
}
}
/// <summary>
/// Private constructor used for deserialization.
/// </summary>
private IpPacket(IpVersion version, byte ihl, byte dscp, ushort totalLength,
ushort identification, IpFlag flags, ushort fragmentOffset,
byte ttl, IpProtocol protocol, ushort checksum, IpAddress source,
IpAddress destination) {
destination.ThrowIfNull("destination");
source.ThrowIfNull("source");
if (ihl > 0x0F)
throw new ArgumentException("The Internet Header Length field must " +
"be in the range from 0 to 15.", nameof(ihl));
if (fragmentOffset > 0x1FFF)
throw new ArgumentException("The Fragment Offset field must be in " +
"the range from 0 to 8191.", nameof(fragmentOffset));
Version = version;
Ihl = ihl;
Dscp = dscp;
TotalLength = totalLength;
Identification = identification;
Flags = flags;
FragmentOffset = fragmentOffset;
TimeToLive = ttl;
Protocol = protocol;
Checksum = checksum;
Source = source;
Destination = destination;
Data = new byte[0];
}
/// <summary>
/// Initializes a new instance of the IpPacket class using the specified
/// values.
/// </summary>
/// <param name="destination">The IPv4 address of the destination
/// host.</param>
/// <param name="source">The IPv4 address of the sending host.</param>
/// <param name="type">The type of the transport protocol encapsulated in
/// the IP packet's data section.</param>
/// <param name="fragmentOffset">The fragment offset of the packet.</param>
/// <param name="data">The transport data to transfer as part of the IP
/// packet.</param>
/// <param name="ihl">The Internet Header Length.</param>
/// <param name="dscp">The Differentiated Services Code Point.</param>
/// <param name="ttl">The time-to-live of the IP packet.</param>
/// <param name="identification">The idenfication used for uniquely identifying
/// fragments of a fragmented IP packet.</param>
/// <param name="flags">The flags set on the IP packet.</param>
/// <exception cref="ArgumentNullException">Thrown if any of the arguments
/// is null.</exception>
public IpPacket(IpAddress destination, IpAddress source,
IpProtocol type, byte ihl, byte dscp, byte ttl, ushort identification,
IpFlag flags, ushort fragmentOffset, byte[] data) {
destination.ThrowIfNull("destination");
source.ThrowIfNull("source");
data.ThrowIfNull("data");
if (ihl > 0x0F)
throw new ArgumentException("The Internet Header Length field must " +
"be in the range from 0 to 15.", nameof(ihl));
if (fragmentOffset > 0x1FFF)
throw new ArgumentException("The Fragment Offset field must be in " +
"the range from 0 to 8191.", nameof(fragmentOffset));
Version = IpVersion.Ipv4;
Ihl = ihl;
Dscp = dscp;
Identification = identification;
Flags = flags;
FragmentOffset = fragmentOffset;
TimeToLive = ttl;
Protocol = type;
Source = source;
Destination = destination;
Data = data;
TotalLength = (ushort) (20 + Data.Length);
Checksum = ComputeChecksum(this);
}
/// <summary>
/// Initializes a new instance of the IpPacket class using the specified
/// values.
/// </summary>
/// <param name="destination">The IPv4 address of the destination
/// host.</param>
/// <param name="source">The IPv4 address of the sending host.</param>
/// <param name="type">The type of the transport protocol encapsulated in
/// the IP packet's data section.</param>
/// <param name="data">The transport data to transfer as part of the IP
/// packet.</param>
/// <exception cref="ArgumentNullException">Thrown if any of the arguments
/// is null.</exception>
public IpPacket(IpAddress destination, IpAddress source,
IpProtocol type, byte[] data) {
destination.ThrowIfNull("destination");
source.ThrowIfNull("source");
data.ThrowIfNull("data");
Destination = destination;
Source = source;
Protocol = type;
Data = data;
TimeToLive = 64;
Ihl = 5;
TotalLength = (ushort) (20 + Data.Length);
Version = IpVersion.Ipv4;
Checksum = ComputeChecksum(this);
}
/// <summary>
/// Sends the specified data to the specified destination address through the
/// specified local interface.
/// </summary>
/// <param name="ifName">The name of the local interface to send the data
/// through.</param>
/// <param name="destination">The IP-address of the destination host.</param>
/// <param name="data">The data to transmit.</param>
public void Output(string ifName, IpAddress destination, byte[] data) {
Network.Output(Interfaces[ifName],
destination,
data,
IpProtocol.Tcp);
}
