in_cksum.h File Reference

#include "ws_symbol_export.h"

Go to the source code of this file.

Classes
struct	vec_t

Macros
#define	SET_CKSUM_VEC_PTR(vecelem, data, length)
#define	SET_CKSUM_VEC_TVB(vecelem, tvb, offset, length)

Functions
WS_DLL_PUBLIC uint16_t	ip_checksum (const uint8_t *ptr, int len)
	Calculate the IP checksum for a given buffer.
WS_DLL_PUBLIC uint16_t	ip_checksum_tvb (tvbuff_t *tvb, int offset, int len)
	Calculate the IP checksum for a given TVB.
WS_DLL_PUBLIC int	in_cksum_ret_partial (const vec_t *vec, int veclen, uint16_t *partial)
	Calculates a partial checksum for a vector of data.
WS_DLL_PUBLIC int	in_cksum (const vec_t *vec, int veclen)
	Calculate the IP checksum for a given vector of data.
WS_DLL_PUBLIC uint16_t	in_cksum_shouldbe (uint16_t sum, uint16_t computed_sum)
	Calculate the expected checksum value based on the computed checksum and the checksum field value.

Detailed Description

Declaration of Internet checksum routine.

Copyright (c) 1988, 1992, 1993 The Regents of the University of California. All rights reserved.

SPDX-License-Identifier: BSD-3-Clause

Macro Definition Documentation

SET_CKSUM_VEC_PTR

#define SET_CKSUM_VEC_PTR	(		vecelem,
			data,
			length
	)

Value:

    G_STMT_START { \
        vecelem.ptr = (data); \
        vecelem.len = (length); \
    } G_STMT_END

SET_CKSUM_VEC_TVB

#define SET_CKSUM_VEC_TVB	(		vecelem,
			tvb,
			offset,
			length
	)

Value:

    G_STMT_START { \
        vecelem.len = (length); \
        vecelem.ptr = tvb_get_ptr((tvb), (offset), vecelem.len); \
    } G_STMT_END

Function Documentation

in_cksum()

WS_DLL_PUBLIC int in_cksum	(	const vec_t *	vec,
		int	veclen
	)

Calculate the IP checksum for a given vector of data.

This function computes the IP checksum for a given vector of data.

Parameters

vec	Pointer to the vector containing the data to be checksummed.
veclen	Number of elements in the vector.

Returns

The calculated IP checksum.

in_cksum_ret_partial()

WS_DLL_PUBLIC int in_cksum_ret_partial	(	const vec_t *	vec,
		int	veclen,
		uint16_t *	partial
	)

Calculates a partial checksum for a vector of data.

This function computes a partial checksum for a given vector of data, storing the intermediate result in the provided partial pointer if it is not null.

Parameters

vec	Pointer to the vector containing the data to be checksummed.
veclen	Number of elements in the vector.
partial	Pointer to store the partial checksum result, can be null.

Returns

The final checksum value.

in_cksum_shouldbe()

WS_DLL_PUBLIC uint16_t in_cksum_shouldbe	(	uint16_t	sum,
		uint16_t	computed_sum
	)

Calculate the expected checksum value based on the computed checksum and the checksum field value.

This function computes the expected checksum value that should be present in the checksum field of a packet, given the computed checksum of the packet's data and the value of the checksum field itself.

Parameters

sum	The value of the checksum field from the packet header.
computed_sum	The computed checksum of the packet's data (excluding the checksum field).

Returns

The expected checksum value that should be in the packet's header for it to be considered valid.

ip_checksum()

WS_DLL_PUBLIC uint16_t ip_checksum	(	const uint8_t *	ptr,
		int	len
	)

Calculate the IP checksum for a given buffer.

Parameters

ptr	Pointer to the data buffer.
len	Length of the data buffer.

Returns

uint16_t The calculated IP checksum.

ip_checksum_tvb()

WS_DLL_PUBLIC uint16_t ip_checksum_tvb	(	tvbuff_t *	tvb,
		int	offset,
		int	len
	)

Calculate the IP checksum for a given TVB.

Parameters

tvb	The TVB containing the data to be checksummed.
offset	The starting offset within the TVB.
len	The length of the data to be checksummed.

Returns

The calculated IP checksum.