/// <summary>
/// Writes the layer to the buffer.
/// </summary>
/// <param name="buffer">The buffer to write the layer to.</param>
/// <param name="offset">The offset in the buffer to start writing the layer at.</param>
/// <param name="payloadLength">The length of the layer's payload (the number of bytes after the layer in the packet).</param>
/// <param name="previousLayer">The layer that comes before this layer. null if this is the first layer.</param>
/// <param name="nextLayer">The layer that comes after this layer. null if this is the last layer.</param>
public override void Write(byte[] buffer, int offset, int payloadLength, ILayer previousLayer, ILayer nextLayer)
{
IpV4Protocol?nextLayerProtocol = null;
if (nextLayer != null)
{
IIpNextLayer ipNextLayer = nextLayer as IIpNextLayer;
if (ipNextLayer != null)
{
nextLayerProtocol = ipNextLayer.PreviousLayerProtocol;
}
}
if (nextLayer != null && ExtensionHeaders.LastHeader == IpV4Protocol.EncapsulatingSecurityPayload)
{
throw new ArgumentException("Cannot have a layer after IpV6Layer with EncapsulatingSecurityPayload extension header.", "nextLayer");
}
if (payloadLength + ExtensionHeaders.BytesLength > ushort.MaxValue)
{
throw new ArgumentOutOfRangeException("payloadLength", payloadLength,
"Consider the extension headers, this must be no more than " +
(ushort.MaxValue - ExtensionHeaders.BytesLength));
}
IpV6Datagram.WriteHeader(buffer, offset,
TrafficClass, FlowLabel, (ushort)(payloadLength + ExtensionHeaders.BytesLength), NextHeader, nextLayerProtocol, HopLimit, Source, CurrentDestination, ExtensionHeaders);
}
/// <summary>
/// Finalizes the layer data in the buffer.
/// Used for fields that must be calculated according to the layer's payload (like checksum).
/// </summary>
/// <param name="buffer">The buffer to finalize the layer in.</param>
/// <param name="offset">The offset in the buffer the layer starts.</param>
/// <param name="payloadLength">The length of the layer's payload (the number of bytes after the layer in the packet).</param>
/// <param name="nextLayer">The layer that comes after this layer. null if this is the last layer.</param>
public override void Finalize(byte[] buffer, int offset, int payloadLength, ILayer nextLayer)
{
IIpNextTransportLayer nextTransportLayer = nextLayer as IIpNextTransportLayer;
if (nextTransportLayer == null || !nextTransportLayer.CalculateChecksum)
{
return;
}
IpV6Datagram.WriteTransportChecksum(buffer, offset, Length, (uint)payloadLength,
nextTransportLayer.ChecksumOffset, nextTransportLayer.IsChecksumOptional,
nextTransportLayer.Checksum, CurrentDestination);
}
private void SkipAuthenticationHeaders(IpV6Datagram ipV6Datagram)
{
while (_currentExtensionHeaderIndex < ipV6Datagram.ExtensionHeaders.Headers.Count &&
ipV6Datagram.ExtensionHeaders[_currentExtensionHeaderIndex].Protocol == IpV4Protocol.AuthenticationHeader)
{
++_currentExtensionHeaderIndex;
}
}
private void IncrementCurrentExtensionHeaderIndex(IpV6Datagram ipV6Datagram)
{
++_currentExtensionHeaderIndex;
SkipAuthenticationHeaders(ipV6Datagram);
}
private void CompareOptions(XElement field, ref int optionsIndex, IpV6Datagram ipV6Datagram, IpV6ExtensionHeaderOptions header)
{
foreach (var headerField in field.Fields())
{
switch (headerField.Name())
{
case "ipv6.nxt":
headerField.AssertNoFields();
headerField.AssertShowDecimal((byte)header.NextHeader);
break;
case "ipv6.opt.length":
headerField.AssertNoFields();
headerField.AssertShowDecimal((header.Length - 8) / 8);
break;
case "ipv6.opt":
foreach (XElement headerSubfield in headerField.Fields())
{
IpV6Option option = header.Options[optionsIndex];
var optionCalipso = option as IpV6OptionCalipso;
var optionQuickStart = option as IpV6OptionQuickStart;
switch (headerSubfield.Name())
{
case "ipv6.opt.type":
headerSubfield.AssertNoFields();
headerSubfield.AssertShowDecimal((byte)option.OptionType);
break;
case "ipv6.opt.length":
headerSubfield.AssertNoFields();
headerSubfield.AssertShowDecimal(option.Length - 2);
break;
case "ipv6.opt.tel":
headerSubfield.AssertNoFields();
IpV6OptionTunnelEncapsulationLimit optionTunnelEncapsulationLimit = (IpV6OptionTunnelEncapsulationLimit)option;
headerSubfield.AssertShowDecimal(optionTunnelEncapsulationLimit.TunnelEncapsulationLimit);
++optionsIndex;
break;
case "ipv6.opt.rpl.flag":
IpV6OptionRoutingProtocolLowPowerAndLossyNetworks optionRoutingProtocolLowPowerAndLossyNetworks =
(IpV6OptionRoutingProtocolLowPowerAndLossyNetworks)option;
foreach (XElement optionSubfield in headerSubfield.Fields())
{
optionSubfield.AssertNoFields();
switch (optionSubfield.Name())
{
case "ipv6.opt.rpl.flag.o":
optionSubfield.AssertShowDecimal(optionRoutingProtocolLowPowerAndLossyNetworks.Down);
break;
case "ipv6.opt.rpl.flag.r":
optionSubfield.AssertShowDecimal(optionRoutingProtocolLowPowerAndLossyNetworks.RankError);
break;
case "ipv6.opt.rpl.flag.f":
optionSubfield.AssertShowDecimal(optionRoutingProtocolLowPowerAndLossyNetworks.ForwardingError);
break;
case "ipv6.opt.rpl.flag.rsv":
optionSubfield.AssertShowDecimal(0);
break;
case "ipv6.opt.rpl.instance_id":
optionSubfield.AssertShowDecimal(
optionRoutingProtocolLowPowerAndLossyNetworks.RoutingProtocolLowPowerAndLossyNetworksInstanceId);
break;
case "ipv6.opt.rpl.sender_rank":
optionSubfield.AssertShowDecimal(optionRoutingProtocolLowPowerAndLossyNetworks.SenderRank);
break;
default:
throw new InvalidOperationException("Invalid ipv6 option subfield " + optionSubfield.Name());
}
}
++optionsIndex;
// TODO: change to break; after https://bugs.wireshark.org/bugzilla/show_bug.cgi?id=10559 is fixed.
return;
case "ipv6.opt.calipso.doi":
headerSubfield.AssertNoFields();
headerSubfield.AssertShowDecimal((uint)optionCalipso.DomainOfInterpretation);
break;
case "ipv6.opt.calipso.cmpt.length":
headerSubfield.AssertNoFields();
headerSubfield.AssertShowDecimal(optionCalipso.CompartmentLength);
break;
case "ipv6.opt.calipso.sens_level":
headerSubfield.AssertNoFields();
headerSubfield.AssertShowDecimal(optionCalipso.SensitivityLevel);
break;
case "ipv6.opt.calipso.checksum":
headerSubfield.AssertNoFields();
headerSubfield.AssertShowDecimal(optionCalipso.Checksum);
break;
case "ipv6.opt.calipso.cmpt_bitmap":
headerSubfield.AssertNoFields();
headerSubfield.AssertValue(optionCalipso.CompartmentBitmap);
++optionsIndex;
break;
case "ipv6.opt.router_alert":
headerSubfield.AssertNoFields();
var optionRouterAlert = (IpV6OptionRouterAlert)option;
headerSubfield.AssertShowDecimal((ushort)optionRouterAlert.RouterAlertType);
++optionsIndex;
break;
case "ipv6.opt.padn":
headerSubfield.AssertNoFields();
var optionPadN = (IpV6OptionPadN)option;
headerSubfield.AssertValue(new byte[optionPadN.PaddingDataLength]);
++optionsIndex;
break;
case "ipv6.opt.qs_func":
headerSubfield.AssertNoFields();
headerSubfield.AssertShowDecimal((byte)optionQuickStart.QuickStartFunction);
break;
case "ipv6.opt.qs_rate":
headerSubfield.AssertNoFields();
headerSubfield.AssertShowDecimal(optionQuickStart.Rate);
break;
case "ipv6.opt.qs_ttl":
headerSubfield.AssertNoFields();
headerSubfield.AssertShowDecimal(optionQuickStart.Ttl);
break;
case "ipv6.opt.qs_ttl_diff":
headerSubfield.AssertNoFields();
headerSubfield.AssertShowDecimal((256 + ipV6Datagram.HopLimit - optionQuickStart.Ttl) % 256);
break;
case "ipv6.opt.qs_unused":
headerSubfield.AssertNoFields();
headerSubfield.AssertShowDecimal(optionQuickStart.Ttl);
break;
case "ipv6.opt.qs_nonce":
headerSubfield.AssertNoFields();
headerSubfield.AssertShowDecimal(optionQuickStart.Nonce);
break;
case "ipv6.opt.qs_reserved":
headerSubfield.AssertNoFields();
headerSubfield.AssertShowDecimal(0);
++optionsIndex;
break;
case "ipv6.opt.pad1":
headerSubfield.AssertNoFields();
headerSubfield.AssertShow("");
Assert.IsTrue(option is IpV6OptionPad1);
++optionsIndex;
break;
case "ipv6.opt.jumbo":
headerSubfield.AssertNoFields();
headerSubfield.AssertShowDecimal(((IpV6OptionJumboPayload)option).JumboPayloadLength);
++optionsIndex;
break;
case "ipv6.mipv6_home_address":
headerSubfield.AssertNoFields();
headerSubfield.AssertShow(((IpV6OptionHomeAddress)option).HomeAddress.GetWiresharkString());
++optionsIndex;
break;
case "ipv6.opt.unknown":
headerSubfield.AssertNoFields();
Assert.IsTrue(new[]
{
IpV6OptionType.LineIdentification,
IpV6OptionType.IdentifierLocatorNetworkProtocolNonce,
IpV6OptionType.SimplifiedMulticastForwardingDuplicatePacketDetection,
IpV6OptionType.EndpointIdentification,
}.Contains(option.OptionType),
option.OptionType.ToString());
++optionsIndex;
break;
default:
throw new InvalidOperationException("Invalid ipv6 header subfield " + headerSubfield.Name());
}
}
break;
default:
throw new InvalidOperationException("Invalid ipv6 options field " + headerField.Name());
}
}
}