void DoPing( uint8_t pingslot )
{
unsigned short ppl;
uint16_t seqnum = ++ClientPingEntries[pingslot].last_send_seqnum;
uint16_t checksum = (seqnum + pingslot + 0x0800) ;
int8_t arpslot = RequestARP( ClientPingEntries[pingslot].ip );
if( arpslot < 0 ) return;
//must set macfrom to be the IP address of the target.
memcpy( macfrom, ClientArpTable[arpslot].mac, 6 );
enc424j600_startsend( NetGetScratch() );
send_etherlink_header( 0x0800 );
send_ip_header( 32, ClientPingEntries[pingslot].ip, 0x01 );
PUSH16( 0x0800 ); //ping request + 0 for code
PUSH16( ~checksum ); //Checksum
PUSH16( pingslot ); //Idneitifer
PUSH16( seqnum ); //Sequence number
PUSH16( 0x0000 ); //Payload
PUSH16( 0x0000 );
enc424j600_start_checksum( 8, 20 );
ppl = enc424j600_get_checksum();
enc424j600_alter_word( 18, ppl );
enc424j600_endsend();
}
/*----------------------------------------------------------------------------*/
uint8_t *
IPOutput(struct mtcp_manager *mtcp, tcp_stream *stream, uint16_t tcplen)
{
struct iphdr *iph;
int nif;
unsigned char *haddr;
if (stream->sndvar->nif_out >= 0) {
nif = stream->sndvar->nif_out;
} else {
nif = GetOutputInterface(stream->daddr);
stream->sndvar->nif_out = nif;
}
haddr = GetDestinationHWaddr(stream->daddr);
if (!haddr) {
#if 0
uint8_t *da = (uint8_t *)&stream->daddr;
TRACE_INFO("[WARNING] The destination IP %u.%u.%u.%u "
"is not in ARP table!\n",
da[0], da[1], da[2], da[3]);
#endif
/* if not found in the arp table, send arp request and return NULL */
/* tcp will retry sending the packet later */
RequestARP(mtcp, stream->daddr, stream->sndvar->nif_out, mtcp->cur_ts);
return NULL;
}
iph = (struct iphdr *)EthernetOutput(mtcp, ETH_P_IP,
stream->sndvar->nif_out, haddr, tcplen + IP_HEADER_LEN);
if (!iph) {
return NULL;
}
iph->ihl = IP_HEADER_LEN >> 2;
iph->version = 4;
iph->tos = 0;
iph->tot_len = htons(IP_HEADER_LEN + tcplen);
iph->id = htons(stream->sndvar->ip_id++);
iph->frag_off = htons(0x4000); // no fragmentation
iph->ttl = 64;
iph->protocol = IPPROTO_TCP;
iph->saddr = stream->saddr;
iph->daddr = stream->daddr;
iph->check = 0;
iph->check = ip_fast_csum(iph, iph->ihl);
return (uint8_t *)(iph + 1);
}
/*----------------------------------------------------------------------------*/
uint8_t *
IPOutputStandalone(struct mtcp_manager *mtcp,
uint16_t ip_id, uint32_t saddr, uint32_t daddr, uint16_t tcplen)
{
struct iphdr *iph;
int nif;
unsigned char * haddr;
nif = GetOutputInterface(daddr);
if (nif < 0)
return NULL;
haddr = GetDestinationHWaddr(daddr);
if (!haddr) {
#if 0
uint8_t *da = (uint8_t *)&daddr;
TRACE_INFO("[WARNING] The destination IP %u.%u.%u.%u "
"is not in ARP table!\n",
da[0], da[1], da[2], da[3]);
#endif
RequestARP(mtcp, daddr, nif, mtcp->cur_ts);
return NULL;
}
iph = (struct iphdr *)EthernetOutput(mtcp,
ETH_P_IP, nif, haddr, tcplen + IP_HEADER_LEN);
if (!iph) {
return NULL;
}
iph->ihl = IP_HEADER_LEN >> 2;
iph->version = 4;
iph->tos = 0;
iph->tot_len = htons(IP_HEADER_LEN + tcplen);
iph->id = htons(ip_id);
iph->frag_off = htons(0x4000); // no fragmentation
iph->ttl = 64;
iph->protocol = IPPROTO_TCP;
iph->saddr = saddr;
iph->daddr = daddr;
iph->check = 0;
iph->check = ip_fast_csum(iph, iph->ihl);
return (uint8_t *)(iph + 1);
}