-static void
-make_echo (const struct in_addr *src_ip,
- struct icmp_echo_packet *echo, uint32_t num)
-{
- memset(echo, 0, sizeof(struct icmp_echo_packet));
- echo->type = ICMP_ECHO;
- echo->code = 0;
- echo->reserved = 0;
- echo->checksum = 0;
- echo->data = htons(num);
- echo->checksum = htons(calc_checksum((uint16_t*)echo,
- sizeof (struct icmp_echo_packet)));
-}
-
-static void
-make_echo2 (const struct in_addr *src_ip,
- struct icmp_packet *echo)
-{
- memset(echo, 0, sizeof(struct icmp_packet));
- echo->type = ICMP_ECHO;
- echo->code = 0;
- echo->reserved = 0;
- echo->checksum = 0;
- echo->checksum = htons(calc_checksum((uint16_t*)echo, sizeof (struct icmp_packet)));
-}
-
-/**
- * Send an ICMP message to the dummy IP.
- *
- * @param my_ip source address (our ip address)
- */
-static void
-send_icmp_echo (const struct in_addr *my_ip)
-{
- struct icmp_packet icmp_echo;
- struct sockaddr_in dst;
- size_t off;
- int err;
- struct ip_packet ip_pkt;
- struct icmp_packet icmp_pkt;
- char packet[sizeof (ip_pkt) + sizeof (icmp_pkt)];
-
- off = 0;
- memset(&ip_pkt, 0, sizeof(ip_pkt));
- ip_pkt.vers_ihl = 0x45;
- ip_pkt.tos = 0;
- ip_pkt.pkt_len = sizeof (packet);
- ip_pkt.id = 1;
- ip_pkt.flags_frag_offset = 0;
- ip_pkt.ttl = IPDEFTTL;
- ip_pkt.proto = IPPROTO_ICMP;
- ip_pkt.checksum = 0;
- ip_pkt.src_ip = my_ip->s_addr;
- ip_pkt.dst_ip = dummy.s_addr;
- ip_pkt.checksum = htons(calc_checksum((uint16_t*)&ip_pkt, sizeof (ip_pkt)));
- memcpy (packet, &ip_pkt, sizeof (ip_pkt));
- off += sizeof (ip_pkt);
- make_echo2 (my_ip, &icmp_echo);
- memcpy (&packet[off], &icmp_echo, sizeof (icmp_echo));
- off += sizeof (icmp_echo);
-
- memset (&dst, 0, sizeof (dst));
- dst.sin_family = AF_INET;
- dst.sin_addr = dummy;
- err = sendto(rawsock,
- packet, off, 0,
- (struct sockaddr*)&dst,
- sizeof(dst));
- if (err < 0)
- {
-#if VERBOSE
- fprintf(stderr,
- "sendto failed: %s\n", strerror(errno));
-#endif
- }
- else if (err != off)
- {
- fprintf(stderr,
- "Error: partial send of ICMP message\n");
- }
-}
-