/*
* This function will send an ICMP echo request to the specified destionation.
*/
static int IcmpSendPing(uint32_t dest, uint16_t id, uint16_t seq, int len)
{
NETBUF *nb;
int i;
uint8_t *dp;
uint32_t spec;
/* Create a new NETBUF. */
nb = NutNetBufAlloc(NULL, NBAF_APPLICATION, len);
if (nb) {
/* Fill the data area with sample characters. */
dp = (uint8_t *) nb->nb_ap.vp;
for (i = 0; i < len; i++) {
*dp++ = 'a' + (i & 15);
}
/* Set up the echo request ID and sequence number. */
spec = id;
spec <<= 16;
spec |= seq;
/* Send out the packet. The name of this function is misleading. */
if (NutIcmpReply(ICMP_ECHO, 0, htonl(spec), dest, nb) == 0) {
/* Funny Nut/Net expects us to release the packet only if
it has been successfully processed. */
NutNetBufFree(nb);
return 0;
}
}
/* Return an error. */
return -1;
}
/*!
* \brief Send an ICMP message as a response to a given destination.
*
* \param type Type of the ICMP message. See NutIcmpOutput() for
* a list of valid types.
* \param code Type subcode.
* \param spec Type specific data item.
* \param nb Network buffer structure containing the previously recevied
* network packet. According to RFC792 the complete ip header
* and the first 8 bytes of the transport netbuf is used as the
* application data for the response. If this function returns
* with an error, the buffer is freed. The destination addess is
* taken from the ip header.
*
* \return 0 on success, -1 otherwise.
*/
int NutIcmpResponse(uint8_t type, uint8_t code, uint32_t spec, NETBUF * nb)
{
IPHDR *ip;
uint32_t dest;
ip = nb->nb_nw.vp;
dest = ip->ip_src;
if ((nb = NutNetBufAlloc(nb, NBAF_APPLICATION, sizeof(IPHDR) + 8)) == 0)
return -1;
memcpy(nb->nb_ap.vp, nb->nb_nw.vp, sizeof(IPHDR));
memcpy((char *)nb->nb_ap.vp + sizeof(IPHDR), nb->nb_tp.vp, 8);
return NutIcmpReply(type, code, spec, dest, nb);
}
