icmp.c File Reference

#include "lwip/opt.h"
#include "lwip/icmp.h"
#include "lwip/inet_chksum.h"
#include "lwip/ip.h"
#include "lwip/def.h"
#include "lwip/stats.h"
#include <string.h>
#include "path/to/my/lwip_hooks.h"

Macros
#define	LWIP_ICMP_ECHO_CHECK_INPUT_PBUF_LEN   1

Functions
void	icmp_input (struct pbuf *p, struct netif *inp)
void	icmp_dest_unreach (struct pbuf *p, enum icmp_dur_type t)
void	icmp_time_exceeded (struct pbuf *p, enum icmp_te_type t)

Detailed Description

ICMP - Internet Control Message Protocol

Macro Definition Documentation

LWIP_ICMP_ECHO_CHECK_INPUT_PBUF_LEN

#define LWIP_ICMP_ECHO_CHECK_INPUT_PBUF_LEN   1

Small optimization: set to 0 if incoming PBUF_POOL pbuf always can be used to modify and send a response packet (and to 1 if this is not the case, e.g. when link header is stripped off when receiving)

Function Documentation

icmp_dest_unreach()

void icmp_dest_unreach	(	struct pbuf *	p,
		enum icmp_dur_type	t
	)

Send an icmp 'destination unreachable' packet, called from ip_input() if the transport layer protocol is unknown and from udp_input() if the local port is not bound.

Parameters

p	the input packet for which the 'unreachable' should be sent, p->payload pointing to the IP header
t	type of the 'unreachable' packet

icmp_input()

void icmp_input	(	struct pbuf *	p,
		struct netif *	inp
	)

Processes ICMP input packets, called from ip_input().

Currently only processes icmp echo requests and sends out the echo response.

Parameters

p	the icmp echo request packet, p->payload pointing to the icmp header
inp	the netif on which this packet was received

icmp_time_exceeded()

void icmp_time_exceeded	(	struct pbuf *	p,
		enum icmp_te_type	t
	)

Send a 'time exceeded' packet, called from ip_forward() if TTL is 0.

Parameters

p	the input packet for which the 'time exceeded' should be sent, p->payload pointing to the IP header
t	type of the 'time exceeded' packet