/// <summary>
/// 指定のバッファから初期化
/// </summary>
/// <param name="buffer">フレームのバッファ</param>
/// <param name="index">フレームの開始位置</param>
/// <param name="count">フレームのバイト数</param>
public Frame(byte[] buffer, int index, int count)
{
using (var memoryStream = new MemoryStream(buffer, index, count, false))
using (var binaryReader = new BinaryReader(memoryStream))
{
// データ長チェック
if (count < MinimumSize)
{
throw new DamagedDataException($"データ長が 共通フレームの長さに満たない。{nameof(count)}={count} {nameof(MinimumSize)}={MinimumSize}");
}
//
Header = binaryReader.ReadUInt16();
DebugWriteLine($"{nameof(Header)}={Header.ToString("X4")}");
if (Header != MagicNumber)
{
// 対応してるデータではない
throw new NotSupportedException($"Header={Header.ToString("X4")}");
}
Length = binaryReader.ReadUInt16();
DebugWriteLine($"{nameof(Length)}={Length}");
// データ長チェック
{
// 本来あるべき全体のサイズ
var requestedLength = Length + TopSize;
if (count < requestedLength)
{
throw new DamagedDataException($"データ長が短い。{nameof(count)}={count} {nameof(requestedLength)}={requestedLength}");
}
}
// CRCチェック
{
memoryStream.Seek(0, SeekOrigin.Begin);// 最初に戻る
var tempBuffer = new byte[Length + TopSize - CRC16Size];
memoryStream.Read(tempBuffer, 0, tempBuffer.Length);
var computedCRC16 = crc16.ComputeHash(tempBuffer);
CRC16 = binaryReader.ReadUInt16();
DebugWriteLine($"{nameof(CRC16)}={CRC16}");
if (CRC16 != computedCRC16)
{
// CRCの結果 データ破損
throw new DamagedDataException($"CRC値の不一致。{nameof(CRC16)}={CRC16.ToString("X4")} {nameof(computedCRC16)}={computedCRC16.ToString("X4")}");
}
}
// Payload読み込み
{
Payload = ResponsePayload.Create(binaryReader, TopSize);
}
}
}
private void btnCRC16_Click(object sender, EventArgs e)
{
System.Diagnostics.Stopwatch watch = new System.Diagnostics.Stopwatch();
Encoding enc = Encoding.GetEncoding(950);
byte[] source = enc.GetBytes(txtCrcSource.Text);
watch.Start();
Crc16 crc = new Crc16();
labCrc16Res.Text = Crc16.Compute(source).ToString("X");
labCrc16Byte.Text = crc.ComputeHash(source).ToHexString();
watch.Stop();
labCrc16Time.Text = watch.ElapsedTicks.ToString() + " Ticks";
watch.Start();
Crc16 modbus = new Crc16(Crc16.DefaultPolynomial, Crc16.ModbusSeed);
labCrc16ResM.Text = Crc16.Compute(source, Crc16.DefaultPolynomial, Crc16.ModbusSeed).ToString("X");
labCrc16ByteM.Text = modbus.ComputeHash(source).ToHexString();
watch.Stop();
labCrc16TimeM.Text = watch.ElapsedTicks.ToString() + " Ticks";
watch.Start();
Crc32 crc32 = new Crc32();
labCrc32Res.Text = Crc32.Compute(source).ToString("X");
labCrc32Byte.Text = crc32.ComputeHash(source).ToHexString();
watch.Stop();
labCrc32Time.Text = watch.ElapsedTicks.ToString() + " Ticks";
}
public void Default()
{
string expected = "0x178C";
var crc = new Crc16();
crc.ComputeHash(Encoding.ASCII.GetBytes("0123456789ABCDEFGHIJKLMNOPQRSTUVWXYZ"));
Assert.Equal(expected, $"0x{crc.HashAsInt16:X4}");
Assert.Equal(expected, "0x" + BitConverter.ToString(crc.Hash).Replace("-", ""));
}
internal bool ChecksumsMatch(IMessage message, byte[] messageFrame)
{
if (message.MessageFrame.Length < (messageFrame.Length - 2))
{
return(false);
}
// Compute the hash
using (Crc16 Hash = new Crc16())
{
Hash.Initialize();
var crc = BitConverter.ToUInt16(Hash.ComputeHash(message.MessageFrame, 0, (messageFrame.Length - 2)), 0);
return(BitConverter.ToUInt16(messageFrame, messageFrame.Length - 2) == crc);
}
}
internal byte[] BuildMessageFrame(IMODBUSMessage message)
{
List <byte> messageBody = new List <byte>();
messageBody.AddRange(message.MessageFrame);
using (Crc16 Hash = new Crc16())
{
Hash.Initialize();
messageBody.AddRange(Hash.ComputeHash(message.MessageFrame, 0, messageBody.Count));
}
return(messageBody.ToArray());
}
public void ShouldComputeCrc16()
{
var crc16 = new Crc16();
// ISO/IEC13239: This should lead to the CRC 0x52ED
byte[] source =
{
0x02, 0x07, 0x01, 0x03, 0x01, 0x02, 0x00, 0x34, 0x07, 0x07, 0x1C, 0x59, 0x34, 0x6F, 0xE1,
0x83, 0x00, 0x00, 0x41, 0x06, 0x06, 0x7B, 0x3C, 0xFF, 0xCF, 0x3C, 0xC0
};
var hash1 = crc16.ComputeHash(source);
Assert.AreEqual("52ED", BitConverter.ToString(hash1).Replace("-", ""));
}
private void btnCrcFile_Click(object sender, EventArgs e)
{
btnFile_Click(btnCrcFile, new EventArgs());
Application.DoEvents();
int times = 1000;
byte[] bs = File.ReadAllBytes(txtCrcFile.Text);
FileStream fs = File.OpenRead(txtCrcFile.Text);
MemoryStream ms = new MemoryStream(bs);
byte[] res = null;
System.Diagnostics.Stopwatch watch = new System.Diagnostics.Stopwatch();
Crc16 crc16 = Crc16.Create();
watch.Start();
for (int i = 0; i < times; i++)
{
res = crc16.ComputeHash(bs);
}
watch.Stop();
lab16B.Text = res.ToHexString("") + " > " + (watch.ElapsedTicks / times).ToString();
Application.DoEvents();
watch.Restart();
for (int i = 0; i < times; i++)
{
res = crc16.ComputeHash(fs);
}
watch.Stop();
lab16S.Text = res.ToHexString("") + " > " + (watch.ElapsedTicks / times).ToString();
Application.DoEvents();
watch.Restart();
for (int i = 0; i < times; i++)
{
res = crc16.ComputeHash(ms);
}
watch.Stop();
lab16M.Text = res.ToHexString("") + " > " + (watch.ElapsedTicks / times).ToString();
Application.DoEvents();
Crc32 crc32 = Crc32.Create();
watch.Start();
for (int i = 0; i < times; i++)
{
res = crc32.ComputeHash(bs);
}
watch.Stop();
lab32B.Text = res.ToHexString("") + " > " + (watch.ElapsedTicks / times).ToString();
Application.DoEvents();
watch.Restart();
for (int i = 0; i < times; i++)
{
res = crc32.ComputeHash(fs);
}
watch.Stop();
lab32S.Text = res.ToHexString("") + " > " + (watch.ElapsedTicks / times).ToString();
Application.DoEvents();
watch.Restart();
for (int i = 0; i < times; i++)
{
res = crc32.ComputeHash(ms);
}
watch.Stop();
lab32M.Text = res.ToHexString("") + " > " + (watch.ElapsedTicks / times).ToString();
Application.DoEvents();
}
/// <summary>
/// Removes the Hdlc Transparency from a List of Byte
/// </summary>
/// <param name="Bytes">The List of Byte to remove the Hdlc Transparency from</param>
/// <param name="IncludeHdlcFields">Specifies the Hdlc Fields retrieved should be included in the the returned Bytes</param>
/// <returns>A List of Bytes which have been decoded from a Transparent state</returns>
public static List <byte> PmppDecode(this List <byte> Bytes, bool IncludeHdlcFields, Transport.SnmpMessenger messengerSession)
{
if (Bytes.Count == 0)
{
return(Bytes);
}
if (Bytes.First() != 0x7e && Bytes.Last() != 0x7e)
{
int firstByte = Bytes.IndexOf(PMPP);
int lastByte = Bytes.LastIndexOf(PMPP);
if (firstByte == lastByte)
{
//offsets are the same....
return(Bytes);
}
Bytes = Bytes.GetRange(firstByte, lastByte);
}
//Removes PMPP Frameing Chars
Bytes.RemoveAt(0);
Bytes.RemoveAt(Bytes.Count - 1);
//Remove Transparency
Int32 Position = 0;
List <byte> Decoded = new List <byte>();
if (!Bytes.Any(b => b == PMPP || b == PMPP_ESCAPE))
{
Decoded.AddRange(Bytes);
}
else
{
for (int end = Bytes.Count; Position < end; ++Position)
{
if (Bytes[Position] == PMPP_ESCAPE)
{
if (Bytes[Position + 1] == 0x5e)
{
Decoded.Add(PMPP);
++Position;
}
else if (Bytes[Position + 1] == 0x5d)
{
Decoded.Add(PMPP_ESCAPE);
++Position;
}
}
else
{
Decoded.Add(Bytes[Position]);
}
}
}
//Get Checksum
List <byte> Checksum = Decoded.GetRange(Decoded.Count - 2, 2);
//Remove Checksum from the working range
Decoded.RemoveRange(Decoded.Count - 2, 2);
//Calculate a Crc16 on the InformationPayload
Crc16 alg = new Crc16();
alg.ComputeHash(Decoded.ToArray());
int?packetChecksum = System.Net.IPAddress.NetworkToHostOrder(BitConverter.ToUInt16(Checksum.ToArray(), 0));
int?pseudoChecksum = System.Net.IPAddress.HostToNetworkOrder((int)alg.CrcValue);
alg = null;
Checksum = null;
//Compare Checksums
if (packetChecksum != pseudoChecksum)
{
if (null != messengerSession)
{
messengerSession.PmppCrcErrors++;
}
}
packetChecksum = null;
pseudoChecksum = null;
//back at the beginning to decode the Hdlc fields
Position = 0;
List <byte> HdlcAddress = new List <byte>();
Byte? HdlcControlField;
List <byte> HdlcProtocolIdentifier = new List <byte>();
HdlcAddress = GetHdlcField(ref Decoded, ref Position);
HdlcControlField = Bytes[Position++];
HdlcProtocolIdentifier = GetHdlcField(ref Decoded, ref Position);
if (!IncludeHdlcFields)
{
//Remove the fields we retrieved
Decoded.RemoveRange(0, Position);
}
HdlcAddress = null;
HdlcControlField = null;
HdlcProtocolIdentifier = null;
Bytes.Clear();
Bytes.AddRange(Decoded);
return(Bytes);
}