/*
* Function: WriteToBuffer
* Description: Deparse and write to a bufferentry
*/
public byte WriteToBuffer(CircularFrameBuffer.BufferEntry be, byte offset)
{
for (byte dataitem = 0; dataitem < 4; dataitem++)
{
ulong data;
if (dataitem > 3)
{
return(0);
}
switch (dataitem)
{
case 0:
data = SrcPort;
break;
case 1:
data = DestPort;
break;
case 2:
data = Length;
break;
case 3:
data = Checksum;
break;
default:
return(1);
}
var linenum = offset / 64;
var lineoffset = offset % 64;
if (lineoffset % 8 != 0)
{
DebugFunctions.push_interrupt(DebugFunctions.Errors.ILLEGAL_PACKET_FORMAT);
}
if (lineoffset <= 48)
{
switch (linenum)
{
case 0:
be.Tdata0 = (be.Tdata0 & ~((ulong)0xffff << lineoffset)) | (data << lineoffset);
break;
case 1:
be.Tdata1 = (be.Tdata1 & ~((ulong)0xffff << lineoffset)) | (data << lineoffset);
break;
case 2:
be.Tdata2 = (be.Tdata2 & ~((ulong)0xffff << lineoffset)) | (data << lineoffset);
break;
case 3:
be.Tdata3 = (be.Tdata3 & ~((ulong)0xffff << lineoffset)) | (data << lineoffset);
break;
}
}
else
{
switch (linenum)
{
case 0:
be.Tdata0 = (be.Tdata0 & ~((ulong)0xffff << lineoffset)) | (data << lineoffset);
be.Tdata1 = (be.Tdata1 & ~((ulong)0xffff >> (64 - lineoffset))) |
(data >> (64 - lineoffset));
break;
case 1:
be.Tdata1 = (be.Tdata1 & ~((ulong)0xffff << lineoffset)) | (data << lineoffset);
be.Tdata2 = (be.Tdata2 & ~((ulong)0xffff >> (64 - lineoffset))) |
(data >> (64 - lineoffset));
break;
case 2:
be.Tdata2 = (be.Tdata2 & ~((ulong)0xffff << lineoffset)) | (data << lineoffset);
be.Tdata3 = (be.Tdata3 & ~((ulong)0xffff >> (64 - lineoffset))) |
(data >> (64 - lineoffset));
break;
case 3:
DebugFunctions.push_interrupt(DebugFunctions.Errors.ILLEGAL_PACKET_FORMAT);
break;
}
}
offset += 16;
}
return(0);
}
/*
* Function: ParseSplit
* Description: A two-part parser to allow the first section of the packet to be parsed.
*/
public byte ParseSplit(CircularFrameBuffer cfb, bool skip = false)
{
//lock (cfb.PeekData)
{
if (!skip)
{
data_0 = cfb.PeekData.Tdata1 >> 48;
data_0 |= cfb.PeekData.Tdata2 << 16;
data_1 = cfb.PeekData.Tdata2 >> 48;
data_1 |= cfb.PeekData.Tdata3 << 16;
data_2 = cfb.PeekData.Tdata3 >> 48;
Version = (byte)((cfb.PeekData.Tdata1 >> 52) & 0x0f);
if (Version != 4)
{
DebugFunctions.push_interrupt(DebugFunctions.Errors.ILLEGAL_PACKET_FORMAT);
}
IHL = (byte)((cfb.PeekData.Tdata1 >> 48) & 0x0f);
if (IHL < 5 || IHL > 8)
{
DebugFunctions.push_interrupt(DebugFunctions.Errors.ILLEGAL_PACKET_FORMAT);
}
DSCP = (byte)((cfb.PeekData.Tdata1 >> 58) & 0x3F);
ECN = (byte)((cfb.PeekData.Tdata1 >> 56) & 0x3);
TotalLength = (uint)(cfb.PeekData.Tdata2 & 0x00ffff);
Identification = (uint)((cfb.PeekData.Tdata2 >> 16) & 0x00ffff);
Flags = (byte)((cfb.PeekData.Tdata2 >> 37) & 0x07);
FragmentOffset = (uint)((((cfb.PeekData.Tdata2 >> 32) & 0x01f) << 8) |
((cfb.PeekData.Tdata2 >> 40) & 0x0ff));
TTL = (byte)((cfb.PeekData.Tdata2 >> 48) & 0x00ff);
Protocol = (byte)((cfb.PeekData.Tdata2 >> 56) & 0x00ff);
HeaderChecksum = (uint)cfb.PeekData.Tdata3 & 0x00ffff;
SrcIp = (cfb.PeekData.Tdata3 >> 16) & 0x00ffffffff;
_tmp_dest_ip = (cfb.PeekData.Tdata3 >> 48) & 0x00ffff;
}
if (!cfb.CanAdvance())
{
return(2);
}
cfb.AdvancePeek();
if (IHL == 5)
{
data_2 |= (cfb.PeekData.Tdata0 & 0xffff) << 16;
}
else if (IHL == 6)
{
data_2 |= cfb.PeekData.Tdata0 << 16;
if (IHL == 7)
{
data_3 = cfb.PeekData.Tdata0 >> 48;
data_3 |= (cfb.PeekData.Tdata1 & 0xffff) << 16;
}
else if (IHL == 8)
{
data_3 = cfb.PeekData.Tdata0 >> 48;
data_3 |= cfb.PeekData.Tdata1 << 16;
}
}
DestIp = _tmp_dest_ip | ((cfb.PeekData.Tdata0 & 0x00ffff) << 16);
}
return(0);
}
