inet_chksum.c File Reference

Incluse internet checksum functions.

#include "lwip/opt.h"
#include "lwip/inet_chksum.h"
#include "lwip/def.h"
#include <stddef.h>
#include <string.h>

Macros
#define	LWIP_CHKSUM   lwip_standard_chksum
#define	LWIP_CHKSUM_ALGORITHM   2

Functions
u16_t	inet_chksum (void *dataptr, u16_t len)
u16_t	inet_chksum_pbuf (struct pbuf *p)
	Calculate a checksum over a chain of pbufs (without pseudo-header, much like inet_chksum only pbufs are used). More...
u16_t	inet_chksum_pseudo (struct pbuf *p, u8_t proto, u16_t proto_len, ip_addr_t *src, ip_addr_t *dest)
u16_t	inet_chksum_pseudo_partial (struct pbuf *p, u8_t proto, u16_t proto_len, u16_t chksum_len, ip_addr_t *src, ip_addr_t *dest)
static u16_t	inet_cksum_pseudo_base (struct pbuf *p, u8_t proto, u16_t proto_len, u32_t acc)
	Parts of the pseudo checksum which are common to IPv4 and IPv6. More...
static u16_t	inet_cksum_pseudo_partial_base (struct pbuf *p, u8_t proto, u16_t proto_len, u16_t chksum_len, u32_t acc)
	Parts of the pseudo checksum which are common to IPv4 and IPv6. More...
u16_t	ip6_chksum_pseudo (struct pbuf *p, u8_t proto, u16_t proto_len, ip6_addr_t *src, ip6_addr_t *dest)
	Calculates the checksum with IPv6 pseudo header used by TCP and UDP for a pbuf chain. More...
u16_t	ip6_chksum_pseudo_partial (struct pbuf *p, u8_t proto, u16_t proto_len, u16_t chksum_len, ip6_addr_t *src, ip6_addr_t *dest)
	Calculates the checksum with IPv6 pseudo header used by TCP and UDP for a pbuf chain. More...
u16_t	lwip_standard_chksum (void *dataptr, int len)

#define LWIP_CHKSUM   lwip_standard_chksum

Referenced by inet_chksum(), inet_chksum_pbuf(), inet_cksum_pseudo_base(), and inet_cksum_pseudo_partial_base().

#define LWIP_CHKSUM_ALGORITHM   2

u16_t inet_chksum	(	void *	dataptr,
		u16_t	len
	)

References LWIP_CHKSUM.

Referenced by icmp_input(), icmp_send_response(), ip_frag(), ip_input(), ip_reass(), ping_prepare_echo(), and tcp_write().

u16_t inet_chksum_pbuf

(

struct pbuf *

p

)

Calculate a checksum over a chain of pbufs (without pseudo-header, much like inet_chksum only pbufs are used).

Parameters

p	pbuf chain over that the checksum should be calculated

Returns

checksum (as u16_t) to be saved directly in the protocol header

References FOLD_U32T, pbuf::len, LWIP_CHKSUM, pbuf::next, NULL, pbuf::payload, and SWAP_BYTES_IN_WORD.

Referenced by icmp_input().

u16_t inet_chksum_pseudo	(	struct pbuf *	p,
		u8_t	proto,
		u16_t	proto_len,
		ip_addr_t *	src,
		ip_addr_t *	dest
	)

References FOLD_U32T, inet_cksum_pseudo_base(), and ip4_addr_get_u32.

u16_t inet_chksum_pseudo_partial	(	struct pbuf *	p,
		u8_t	proto,
		u16_t	proto_len,
		u16_t	chksum_len,
		ip_addr_t *	src,
		ip_addr_t *	dest
	)

References FOLD_U32T, inet_cksum_pseudo_partial_base(), and ip4_addr_get_u32.

static u16_t inet_cksum_pseudo_base ( struct pbuf *  p, u8_t  proto, u16_t  proto_len, u32_t  acc  )

static

Parts of the pseudo checksum which are common to IPv4 and IPv6.

References FOLD_U32T, htons, INET_DEBUG, pbuf::len, LWIP_CHKSUM, LWIP_DEBUGF, pbuf::next, NULL, pbuf::payload, SWAP_BYTES_IN_WORD, and X32_F.

Referenced by inet_chksum_pseudo(), and ip6_chksum_pseudo().

static u16_t inet_cksum_pseudo_partial_base ( struct pbuf *  p, u8_t  proto, u16_t  proto_len, u16_t  chksum_len, u32_t  acc  )

static

Parts of the pseudo checksum which are common to IPv4 and IPv6.

References FOLD_U32T, htons, INET_DEBUG, pbuf::len, LWIP_ASSERT, LWIP_CHKSUM, LWIP_DEBUGF, pbuf::next, NULL, pbuf::payload, SWAP_BYTES_IN_WORD, and X32_F.

Referenced by inet_chksum_pseudo_partial(), and ip6_chksum_pseudo_partial().

u16_t ip6_chksum_pseudo	(	struct pbuf *	p,
		u8_t	proto,
		u16_t	proto_len,
		ip6_addr_t *	src,
		ip6_addr_t *	dest
	)

Calculates the checksum with IPv6 pseudo header used by TCP and UDP for a pbuf chain.

IPv6 addresses are expected to be in network byte order.

Parameters

p	chain of pbufs over that a checksum should be calculated (ip data part)
src	source ipv6 address (used for checksum of pseudo header)
dst	destination ipv6 address (used for checksum of pseudo header)
proto	ipv6 protocol/next header (used for checksum of pseudo header)
proto_len	length of the ipv6 payload (used for checksum of pseudo header)

Returns

checksum (as u16_t) to be saved directly in the protocol header

References FOLD_U32T, and inet_cksum_pseudo_base().

Referenced by icmp6_input(), icmp6_send_response(), mld6_send(), nd6_send_na(), nd6_send_ns(), nd6_send_rs(), and raw_sendto().

u16_t ip6_chksum_pseudo_partial	(	struct pbuf *	p,
		u8_t	proto,
		u16_t	proto_len,
		u16_t	chksum_len,
		ip6_addr_t *	src,
		ip6_addr_t *	dest
	)

Calculates the checksum with IPv6 pseudo header used by TCP and UDP for a pbuf chain.

IPv6 addresses are expected to be in network byte order. Will only compute for a portion of the payload.

Parameters

p	chain of pbufs over that a checksum should be calculated (ip data part)
src	source ipv6 address (used for checksum of pseudo header)
dst	destination ipv6 address (used for checksum of pseudo header)
proto	ipv6 protocol/next header (used for checksum of pseudo header)
proto_len	length of the ipv6 payload (used for checksum of pseudo header)
chksum_len	number of payload bytes used to compute chksum

Returns

checksum (as u16_t) to be saved directly in the protocol header

References FOLD_U32T, and inet_cksum_pseudo_partial_base().

u16_t lwip_standard_chksum	(	void *	dataptr,
		int	len
	)

References FOLD_U32T, and SWAP_BYTES_IN_WORD.