void reply_udp_payload(tw_rx_t * handle, tw_buf_t * buffer) {
eth = buffer->data;
eth_type = tw_be_to_cpu_16(eth->ether_type);
switch (eth_type) {
case ETHER_TYPE_ARP:
tw_arp_parser(buffer, "tw0");
break;
case ETHER_TYPE_IPv4:
ipHdr_d = buffer->data + sizeof(struct ether_hdr);
dst_ip = (ipHdr_d->dst_addr);
src_ip = (ipHdr_d->src_addr);
ipHdr_d->dst_addr = (src_ip);
ipHdr_d->src_addr = (dst_ip);
ipHdr_d->hdr_checksum = tw_ipv4_cksum(ipHdr_d);
udp_hdr_d = (struct udp_hdr *)ipHdr_d + sizeof(struct ipv4_hdr);
dst_port = (udp_hdr_d->dst_port);
src_port = (udp_hdr_d->src_port);
udp_hdr_d->dst_port = (src_port);
udp_hdr_d->src_port = (dst_port);
udp_hdr_d->dgram_cksum = 0;
tw_copy_ether_addr(&(eth->s_addr), &(eth->d_addr));
tw_copy_ether_addr(dst_eth, &(eth->s_addr));
tw_send_pkt(buffer, "tw0");
break;
}
}
void reply_payload(tw_rx_t * handle, tw_buf_t * buffer)
{
struct ether_hdr * eth = buffer->data;
tw_copy_ether_addr(&(eth->s_addr), &(eth->d_addr));
tw_copy_ether_addr(dst_eth, &(eth->s_addr));
tw_send_pkt(buffer, "tw0");
}
void pkt_tx(tw_tx_t * handle)
{
curr_time_cycle = tw_get_current_timer_cycles();
if((curr_time_cycle - prev_stats_calc) > ppsdelay)
{
prev_stats_calc=curr_time_cycle;
if((global_stats_option.pkts_tx < PacketLimit || PacketLimit == 0) && (global_stats_option.secs_passed < user_params.test_runtime || user_params.test_runtime == 0))
{
if (dst_eth_addr == NULL) {
struct arp_table * temp_arp_entry = tw_search_arp_table(tw_be_to_cpu_32(user_params.server_ip));
if(temp_arp_entry == NULL )
{
if (arp_secs!=global_stats_option.secs_passed) {
tw_construct_arp_packet(user_params.server_ip, phy_port_id);
arp_secs=global_stats_option.secs_passed;
total_arps++;
} else
{
return;
}
}
else
dst_eth_addr = &temp_arp_entry->eth_mac;
}
else {
eth = tx_buf->data;
ip = (struct ipv4_hdr* )(eth + 1);
udp = (struct udp_hdr* )(ip + 1);
udp->src_port = tw_cpu_to_be_16(7777);
udp->dst_port = tw_cpu_to_be_16(user_params.server_port);
udp->dgram_len = tw_cpu_to_be_16(tx_buf->size - sizeof(struct ether_hdr) - sizeof(struct ipv4_hdr));
udp->dgram_cksum = 0;
ip->total_length = tw_cpu_to_be_16(tx_buf->size - sizeof(struct ether_hdr));
ip->next_proto_id = UDP_PROTO_ID;
ip->src_addr = ipv4_tw0;
ip->dst_addr = tw_cpu_to_be_32(user_params.server_ip);
ip->version_ihl = 0x45;
ip->time_to_live = 63;
ip->hdr_checksum =tw_ipv4_cksum(ip);
eth->ether_type = tw_cpu_to_be_16(ETHER_TYPE_IPv4);
tw_copy_ether_addr(dst_eth_addr, &(eth->d_addr));
tw_copy_ether_addr(port_info[phy_port_id].eth_mac, &(eth->s_addr));
tw_send_pkt(tx_buf, "tw0");
}
}
}
}
/* reply_udp_payload acts as udp server; switches the IP and ports, mac addresses and echoes back the packet to sender*/
void reply_udp_payload(tw_rx_t * handle, tw_buf_t * buffer)
{
test_stats.datagrams_recv++;
eth = buffer->data;
eth_type = tw_be_to_cpu_16(eth->ether_type);
ipHdr_d = buffer->data + sizeof(struct ether_hdr);
dst_ip = (ipHdr_d->dst_addr);
src_ip = (ipHdr_d->src_addr);
ipHdr_d->dst_addr = (src_ip);
ipHdr_d->src_addr = (dst_ip);
ipHdr_d->hdr_checksum = tw_ipv4_cksum(ipHdr_d);
udp_hdr_d = (struct udp_hdr *) ipHdr_d + sizeof(struct ipv4_hdr);
dst_port = (udp_hdr_d->dst_port);
src_port = (udp_hdr_d->src_port);
udp_hdr_d->dst_port = (src_port);
udp_hdr_d->src_port = (dst_port);
udp_hdr_d->dgram_cksum = 0;
tw_copy_ether_addr(&(eth->s_addr), &(eth->d_addr));
tw_copy_ether_addr(test.server_mac, &(eth->s_addr));
tw_send_pkt(buffer, "tw0");
test_stats.datagrams_sent++;
}