Class ChecksumUtils

Namespace

VpnHood.Net.Packets

Assembly

VpnHood.Net.Packets.dll

Provides the Internet checksum (RFC 1071), vectorized where the processor allows.

public static class ChecksumUtils

Inheritance

object

ChecksumUtils

Inherited Members

object.Equals(object)

object.Equals(object, object)

object.GetHashCode()

object.GetType()

object.MemberwiseClone()

object.ReferenceEquals(object, object)

object.ToString()

Methods

ComputeChecksum(ReadOnlySpan<byte>)

Computes the Internet checksum of some bytes: the complement of the ones' complement sum of their 16-bit words.

public static ushort ComputeChecksum(ReadOnlySpan<byte> data)

Parameters

data ReadOnlySpan<byte>

The bytes to sum, with any checksum field among them zero.

Returns

ushort

The checksum, as a number to write in network byte order.

Remarks

Over bytes that already hold a valid checksum it returns zero.

ComputeChecksum(ReadOnlySpan<byte>, ReadOnlySpan<byte>)

Computes the Internet checksum of a pseudo-header followed by some bytes, as if the two were one buffer.

public static ushort ComputeChecksum(ReadOnlySpan<byte> pseudoHeader, ReadOnlySpan<byte> data)

Parameters

pseudoHeader ReadOnlySpan<byte>

The bytes summed first, such as an IP pseudo-header; may be empty or odd in length.

data ReadOnlySpan<byte>

The bytes summed after them, with any checksum field among them zero.

Returns

ushort

The checksum, as a number to write in network byte order.

Remarks

A computed zero is returned as it is; UDP's rule to send it as 0xFFFF is ComputeChecksum(ReadOnlySpan<byte>, ReadOnlySpan<byte>)'s.