apps/linker
1
0
Fork 0
mirror of https://github.com/snltty/linker.git synced 2025-10-05 17:16:56 +08:00
Code Issues Packages Projects Releases Wiki Activity

池化

Browse Source
This commit is contained in:
snltty
2025-09-19 16:42:34 +08:00
parent d45c5af059
commit 5b0890a05f
20 changed files with 140 additions and 232 deletions
Download Patch File Download Diff File Expand all files Collapse all files

45
src/linker.libs/ChecksumHelper.cs
View File

@@ -11,37 +11,42 @@ namespace linker.libs
/// </summary>
/// <param name="packet">一个完整的IP包</param>
/// <param name="payload">是否计算荷载协议校验和</param>
public static unsafe void Checksum(ReadOnlyMemory<byte> packet,bool payload = true)
public static unsafe void Checksum(ReadOnlyMemory<byte> packet, bool ipHeader = true, bool payload = true)
{
fixed (byte* ptr = packet.Span)
{
Checksum(ptr, packet.Length, payload);
}
Checksum(packet.Span, ipHeader, payload);
}
/// <summary>
/// 计算IP包的校验和
/// </summary>
/// <param name="packet">一个完整的IP包</param>
/// <param name="payload">是否计算荷载协议校验和</param>
public static unsafe void Checksum(ReadOnlySpan<byte> packet, bool payload = true)
public static unsafe void Checksum(ReadOnlySpan<byte> packet, bool ipHeader = true, bool payload = true)
{
fixed (byte* ptr = packet)
{
Checksum(ptr, packet.Length, payload);
Checksum(ptr, ipHeader, payload);
}
}
/// <summary>
/// 计算IP包的校验和
/// </summary>
/// <param name="ptr">IP包指针</param>
/// <param name="length">IP包长度</param>
/// <param name="ipHeader">是否计算IP校验和</param>
/// <param name="payload">是否计算荷载协议校验和</param>
public static unsafe void Checksum(byte* ptr, int length, bool payload = true)
public static unsafe void Checksum(byte* ptr, bool ipHeader = true, bool payload = true)
{
byte ipHeaderLength = (byte)((*ptr & 0b1111) * 4);
//重新计算IP头校验和
*(ushort*)(ptr + 10) = 0;
*(ushort*)(ptr + 10) = Checksum((ushort*)ptr, ipHeaderLength);
byte* packetPtr = ptr + ipHeaderLength;
uint totalLength = BinaryPrimitives.ReverseEndianness(*(ushort*)(ptr + 2));
uint packetLength = totalLength - ipHeaderLength;
if (ipHeader)
{
//重新计算IP头校验和
*(ushort*)(ptr + 10) = 0;
*(ushort*)(ptr + 10) = Checksum((ushort*)ptr, ipHeaderLength);
}
if (payload)
{
@@ -50,22 +55,22 @@ namespace linker.libs
{
case ProtocolType.Tcp:
{
*(ushort*)(ptr + ipHeaderLength + 16) = 0;
ulong sum = PseudoHeaderSum(ptr, (uint)(length - ipHeaderLength));
*(ushort*)(ptr + ipHeaderLength + 16) = Checksum((ushort*)(ptr + ipHeaderLength), (uint)length - ipHeaderLength, sum);
*(ushort*)(packetPtr + 16) = 0;
ulong sum = PseudoHeaderSum(ptr, packetLength);
*(ushort*)(packetPtr + 16) = Checksum((ushort*)(packetPtr), packetLength, sum);
}
break;
case ProtocolType.Udp:
{
*(ushort*)(ptr + ipHeaderLength + 6) = 0;
ulong sum = PseudoHeaderSum(ptr, (uint)(length - ipHeaderLength));
*(ushort*)(ptr + ipHeaderLength + 6) = Checksum((ushort*)(ptr + ipHeaderLength), (uint)length - ipHeaderLength, sum);
*(ushort*)(packetPtr + 6) = 0;
ulong sum = PseudoHeaderSum(ptr, packetLength);
*(ushort*)(packetPtr + 6) = Checksum((ushort*)(packetPtr), packetLength, sum);
}
break;
case ProtocolType.Icmp:
{
*(ushort*)(ptr + ipHeaderLength + 2) = 0;
*(ushort*)(ptr + ipHeaderLength + 2) = Checksum((ushort*)(ptr + ipHeaderLength), (uint)length - ipHeaderLength);
*(ushort*)(packetPtr + 2) = 0;
*(ushort*)(packetPtr + 2) = Checksum((ushort*)(packetPtr), packetLength);
}
break;
}