/// <summary>
/// Attempts to parse raw data into a structured packet
/// </summary>
/// <param name="buffer">Raw data to parse</param>
/// <param name="packet">Parsed packet</param>
/// <param name="count">The length of the packet in bytes</param>
/// <param name="index">The index into the buffer at which the packet begins</param>
/// <returns>True if parsing was successful, false if it is not.</returns>
internal static bool TryParse(byte[] buffer, int index, int count, out Radiotap packet)
{
try
{
using (var ms = new MemoryStream(buffer, index, count, false))
{
using (var br = new BinaryReader(ms))
{
var version = br.ReadByte();
var pad = br.ReadByte();
var length = br.ReadUInt16();
var present = br.ReadUInt32();
if (count - br.BaseStream.Position < length - 8)
{
packet = null;
return(false);
}
var fieldData = br.ReadBytes(length - 8);
packet = null;
IEEE802_11 payload80211;
if (IEEE802_11.TryParse(
buffer,
index + (int)br.BaseStream.Position,
(int)(count - br.BaseStream.Position),
out payload80211))
{
packet = new Radiotap <IEEE802_11> {
Payload = payload80211
};
}
if (packet == null)
{
Generic payload;
Generic.TryParse(
buffer,
index + (int)br.BaseStream.Position,
(int)(count - br.BaseStream.Position),
out payload);
// This can never fail, so I'm not checking the output
packet = new Radiotap <Generic> {
Payload = payload
};
}
packet.Version = version;
packet.Pad = pad;
packet.LengthRadiotap = length;
packet.Present = present;
packet.FieldData = fieldData;
return(true);
}
}
}
catch (Exception)
{
packet = null;
return(false);
}
}
/// <summary>
/// Attempts to parse raw data into a structured packet
/// </summary>
/// <param name="buffer">Raw data to parse</param>
/// <param name="packet">Parsed packet</param>
/// <param name="count">The length of the packet in bytes</param>
/// <param name="index">The index into the buffer at which the packet begins</param>
/// <returns>True if parsing was successful, false if it is not.</returns>
internal static bool TryParse(byte[] buffer, int index, int count, out Generic packet)
{
try
{
var data = new byte[count];
Array.Copy(buffer, index, data, 0, count);
packet = new Generic { Buffer = data };
return true;
}
catch (Exception)
{
packet = null;
return false;
}
}
/// <summary>
/// Attempts to parse raw data into a structured packet
/// </summary>
/// <param name="buffer">Raw data to parse</param>
/// <param name="packet">Parsed packet</param>
/// <param name="count">The length of the packet in bytes</param>
/// <param name="index">The index into the buffer at which the packet begins</param>
/// <returns>True if parsing was successful, false if it is not.</returns>
internal static bool TryParse(byte[] buffer, int index, int count, out EthernetII packet)
{
try
{
if (count < MinimumParseableBytes)
{
packet = null;
return(false);
}
using (var ms = new MemoryStream(buffer, index, count, false))
{
using (var br = new BinaryReader(ms))
{
var dstMac = br.ReadBytes(6);
var srcMac = br.ReadBytes(6);
var etherType = ByteOrder.NetworkToHostOrder(br.ReadUInt16());
packet = null;
switch (etherType)
{
case (ushort)EtherTypes.IPv4:
{
IPv4 payload;
if (IPv4.TryParse(
buffer,
index + (int)br.BaseStream.Position,
(int)(count - br.BaseStream.Position),
out payload))
{
packet = new EthernetII <IPv4> {
Payload = payload
};
}
}
break;
case (ushort)EtherTypes.ARP:
{
ARP payload;
if (ARP.TryParse(
buffer,
index + (int)br.BaseStream.Position,
(int)(count - br.BaseStream.Position),
out payload))
{
packet = new EthernetII <ARP> {
Payload = payload
};
}
}
break;
}
if (packet == null)
{
Generic payload;
Generic.TryParse(
buffer,
index + (int)br.BaseStream.Position,
(int)(count - br.BaseStream.Position),
out payload);
// This can never fail, so I'm not checking the output
packet = new EthernetII <Generic> {
Payload = payload
};
}
packet.DstMac = dstMac;
packet.EtherType = etherType;
packet.SrcMac = srcMac;
return(true);
}
}
}
catch (Exception)
{
packet = null;
return(false);
}
}