* Copyright 2008-2010, Haiku, Inc. All Rights Reserved.
* Distributed under the terms of the MIT License.
*
* Authors:
* Yin Qiu
*/
#include <arpa/inet.h>
#include <errno.h>
#include <netinet/in.h>
#include <netinet/ip.h>
#include <netinet/ip_icmp.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <sys/socket.h>
#include <unistd.h>
#define MAXLEN 4096
int
main(void)
{
int sockfd = socket(AF_INET, SOCK_RAW, IPPROTO_ICMP);
if (sockfd < 0) {
fprintf(stderr, "Could not open raw socket: %s\n", strerror(errno));
return 1;
}
struct sockaddr_in source;
socklen_t addrLen = sizeof(source);
char buf[MAXLEN];
ssize_t nbytes;
while ((nbytes = recvfrom(sockfd, buf, MAXLEN, 0,
(struct sockaddr*)&source, &addrLen)) > 0) {
int ipLen, icmpLen;
char host[128];
if (!inet_ntop(AF_INET, &source.sin_addr, host, sizeof(host)))
strcpy(host, "<unknown host>");
printf("Received %zd bytes of ICMP message from %s\n", nbytes, host);
struct ip* ip = (struct ip*)buf;
ipLen = ip->ip_hl << 2;
if ((icmpLen = nbytes - ipLen) < 8) {
fprintf(stderr, "ICMP len (%d) < 8\n", icmpLen);
exit(1);
}
struct icmp* icmp = (struct icmp*)(buf + ipLen);
printf("Type: %u; Code: %u\n", icmp->icmp_type, icmp->icmp_code);
}
return 0;
}
