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/* -*- P4_16 -*- */
#include <core.p4>
#include <v1model.p4>
/*************************************************************************
*********************** C O N S T A N T S *****************************
*************************************************************************/
/* Define the useful global constants for your program */
const bit<16> ETHERTYPE_IPV4 = 0x0800;
const bit<16> ETHERTYPE_ARP = 0x0806;
const bit<8> IPPROTO_ICMP = 0x01;
/*************************************************************************
*********************** H E A D E R S *********************************
*************************************************************************/
/* Define the headers the program will recognize */
/*
* Standard ethernet header
*/
typedef bit<48> mac_addr_t;
typedef bit<32> ipv4_addr_t;
typedef bit<9> port_id_t;
header ethernet_t {
mac_addr_t dstAddr;
mac_addr_t srcAddr;
bit<16> etherType;
}
header ipv4_t {
bit<4> version;
bit<4> ihl;
bit<8> diffserv;
bit<16> totalLen;
bit<16> identification;
bit<3> flags;
bit<13> fragOffset;
bit<8> ttl;
bit<8> protocol;
bit<16> hdrChecksum;
ipv4_addr_t srcAddr;
ipv4_addr_t dstAddr;
}
const bit<16> ARP_HTYPE_ETHERNET = 0x0001;
const bit<16> ARP_PTYPE_IPV4 = 0x0800;
const bit<8> ARP_HLEN_ETHERNET = 6;
const bit<8> ARP_PLEN_IPV4 = 4;
const bit<16> ARP_OPER_REQUEST = 1;
const bit<16> ARP_OPER_REPLY = 2;
header arp_t {
bit<16> htype;
bit<16> ptype;
bit<8> hlen;
bit<8> plen;
bit<16> oper;
}
header arp_ipv4_t {
mac_addr_t sha;
ipv4_addr_t spa;
mac_addr_t tha;
ipv4_addr_t tpa;
}
const bit<8> ICMP_ECHO_REQUEST = 8;
const bit<8> ICMP_ECHO_REPLY = 0;
header icmp_t {
bit<8> type;
bit<8> code;
bit<16> checksum;
}
/* Assemble headers in a single struct */
struct my_headers_t {
ethernet_t ethernet;
arp_t arp;
arp_ipv4_t arp_ipv4;
ipv4_t ipv4;
icmp_t icmp;
}
/*************************************************************************
*********************** M E T A D A T A *******************************
*************************************************************************/
/* Define the global metadata for your program */
struct my_metadata_t {
ipv4_addr_t dst_ipv4;
mac_addr_t mac_da;
mac_addr_t mac_sa;
port_id_t egress_port;
mac_addr_t my_mac;
}
/*************************************************************************
*********************** P A R S E R ***********************************
*************************************************************************/
parser MyParser(
packet_in packet,
out my_headers_t hdr,
inout my_metadata_t meta,
inout standard_metadata_t standard_metadata)
{
state start {
packet.extract(hdr.ethernet);
transition select(hdr.ethernet.etherType) {
ETHERTYPE_IPV4 : parse_ipv4;
ETHERTYPE_ARP : parse_arp;
default : accept;
}
}
state parse_arp {
packet.extract(hdr.arp);
transition select(hdr.arp.htype, hdr.arp.ptype,
hdr.arp.hlen, hdr.arp.plen) {
(ARP_HTYPE_ETHERNET, ARP_PTYPE_IPV4,
ARP_HLEN_ETHERNET, ARP_PLEN_IPV4) : parse_arp_ipv4;
default : accept;
}
}
state parse_arp_ipv4 {
packet.extract(hdr.arp_ipv4);
meta.dst_ipv4 = hdr.arp_ipv4.tpa;
transition accept;
}
state parse_ipv4 {
packet.extract(hdr.ipv4);
meta.dst_ipv4 = hdr.ipv4.dstAddr;
transition select(hdr.ipv4.protocol) {
IPPROTO_ICMP : parse_icmp;
default : accept;
}
}
state parse_icmp {
packet.extract(hdr.icmp);
transition accept;
}
}
/*************************************************************************
************ C H E C K S U M V E R I F I C A T I O N *************
*************************************************************************/
control MyVerifyChecksum(
inout my_headers_t hdr,
inout my_metadata_t meta)
{
apply { }
}
/*************************************************************************
************** I N G R E S S P R O C E S S I N G *******************
*************************************************************************/
control MyIngress(
inout my_headers_t hdr,
inout my_metadata_t meta,
inout standard_metadata_t standard_metadata)
{
action drop() {
mark_to_drop();
exit;
}
action set_dst_info(mac_addr_t mac_da,
mac_addr_t mac_sa,
port_id_t egress_port)
{
meta.mac_da = mac_da;
meta.mac_sa = mac_sa;
meta.egress_port = egress_port;
}
table ipv4_lpm {
key = { meta.dst_ipv4 : lpm; }
actions = { set_dst_info; drop; }
default_action = drop();
}
action forward_ipv4() {
hdr.ethernet.dstAddr = meta.mac_da;
hdr.ethernet.srcAddr = meta.mac_sa;
hdr.ipv4.ttl = hdr.ipv4.ttl - 1;
standard_metadata.egress_spec = meta.egress_port;
}
action send_arp_reply() {
hdr.ethernet.dstAddr = hdr.arp_ipv4.sha;
hdr.ethernet.srcAddr = meta.mac_da;
hdr.arp.oper = ARP_OPER_REPLY;
hdr.arp_ipv4.tha = hdr.arp_ipv4.sha;
hdr.arp_ipv4.tpa = hdr.arp_ipv4.spa;
hdr.arp_ipv4.sha = meta.mac_da;
hdr.arp_ipv4.spa = meta.dst_ipv4;
standard_metadata.egress_spec = standard_metadata.ingress_port;
}
action send_icmp_reply() {
mac_addr_t tmp_mac;
ipv4_addr_t tmp_ip;
tmp_mac = hdr.ethernet.dstAddr;
hdr.ethernet.dstAddr = hdr.ethernet.srcAddr;
hdr.ethernet.srcAddr = tmp_mac;
tmp_ip = hdr.ipv4.dstAddr;
hdr.ipv4.dstAddr = hdr.ipv4.srcAddr;
hdr.ipv4.srcAddr = tmp_ip;
hdr.icmp.type = ICMP_ECHO_REPLY;
hdr.icmp.checksum = 0; // For now
standard_metadata.egress_spec = standard_metadata.ingress_port;
}
table forward {
key = {
hdr.arp.isValid() : exact;
hdr.arp.oper : ternary;
hdr.arp_ipv4.isValid() : exact;
hdr.ipv4.isValid() : exact;
hdr.icmp.isValid() : exact;
hdr.icmp.type : ternary;
}
actions = {
forward_ipv4;
send_arp_reply;
send_icmp_reply;
drop;
}
const default_action = drop();
const entries = {
( true, ARP_OPER_REQUEST, true, false, false, _ ) :
send_arp_reply();
( false, _, false, true, false, _ ) :
forward_ipv4();
( false, _, false, true, true, ICMP_ECHO_REQUEST ) :
send_icmp_reply();
}
}
apply {
meta.my_mac = 0x000102030405;
ipv4_lpm.apply();
forward.apply();
}
}
/*************************************************************************
**************** E G R E S S P R O C E S S I N G *******************
*************************************************************************/
control MyEgress(
inout my_headers_t hdr,
inout my_metadata_t meta,
inout standard_metadata_t standard_metadata) {
apply { }
}
/*************************************************************************
************* C H E C K S U M C O M P U T A T I O N **************
*************************************************************************/
control MyComputeChecksum(
inout my_headers_t hdr,
inout my_metadata_t meta)
{
apply { }
}
/*************************************************************************
*********************** D E P A R S E R *******************************
*************************************************************************/
control MyDeparser(
packet_out packet,
in my_headers_t hdr)
{
apply {
packet.emit(hdr.ethernet);
/* ARP Case */
packet.emit(hdr.arp);
packet.emit(hdr.arp_ipv4);
/* IPv4 case */
packet.emit(hdr.ipv4);
packet.emit(hdr.icmp);
}
}
V1Switch(
MyParser(),
MyVerifyChecksum(),
MyIngress(),
MyEgress(),
MyComputeChecksum(),
MyDeparser()
) main;