P4交换机实现

#include <core.p4>
#include <v1model.p4>
  
const bit<16> TYPE_IPV4 = 0x800;
const bit<16> TYPE_VLAN = 0x8100;
#define MAX_VLAN_TAG_NUM 2
const bit<16> L2_LEARN_ETHER_TYPE = 0x1234;
/*************************************************************************
*********************** H E A D E R S  ***********************************
*************************************************************************/
  
typedef bit<9>  egressSpec_t;
typedef bit<48> macAddr_t;
typedef bit<32> ip4Addr_t;
 
header ethernet_t {
    macAddr_t dstAddr;
    macAddr_t srcAddr;
    bit<16>   etherType;
}
  
header vlan_tag_t {
    bit<3>   prio;
    bit<1>   cfi;
    bit<12>  vid;
    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;
    ip4Addr_t srcAddr;
    ip4Addr_t dstAddr;
}
 
struct metadata {
    /* empty */
    bit<9> ingress_port;
    bit<12> vid;
	bit<1>  rmac_hit;
	bit<1>  l2_hit;
}
  
struct port_metadata {
    bit<4> type;
}
  
header cpu_t {
    bit<48> srcAddr;        // 源 MAC 地址
    bit<16> ingress_port;   // 交换机的接收端口
}
  
struct headers {
    ethernet_t                     ethernet;
    cpu_t                          cpu;
    vlan_tag_t[MAX_VLAN_TAG_NUM]   vlan_tag;
    ipv4_t                         ipv4;
}
  
/*************************************************************************
*********************** P A R S E R  ***********************************
*************************************************************************/
  
parser MyParser(packet_in packet,
                out headers hdr,
                inout metadata meta,
                inout standard_metadata_t standard_metadata) {
  
    state start {
        /* TODO: add parser logic */
        transition parse_ethernet;
    }
      
    state parse_ethernet {
        packet.extract(hdr.ethernet);
        transition select(hdr.ethernet.etherType) {
            TYPE_VLAN : parse_vlan_tag;
            TYPE_IPV4 : parse_ipv4;
            default   : accept;
        }
    }
      
    state parse_vlan_tag {
        packet.extract(hdr.vlan_tag.next);
        transition select(hdr.vlan_tag.last.etherType) {
            TYPE_VLAN : parse_vlan_tag;
            TYPE_IPV4 : parse_ipv4;
            default   : accept;
        }
    }
      
    state parse_ipv4 {
        packet.extract(hdr.ipv4);
        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 headers hdr, inout metadata meta) {
    apply {  }
}
  
  
/*************************************************************************
**************  I N G R E S S   P R O C E S S I N G   *******************
*************************************************************************/
  
control MyIngress(inout headers hdr,
                  inout metadata meta,
                  inout standard_metadata_t standard_metadata) {
    action drop() {
        mark_to_drop(standard_metadata);
    }
  
    
    action ipv4_forward(macAddr_t dstAddr, egressSpec_t port) {
        standard_metadata.egress_spec = port;
        hdr.ethernet.srcAddr = hdr.ethernet.dstAddr;
        hdr.ethernet.dstAddr = dstAddr;
        hdr.ipv4.ttl = hdr.ipv4.ttl - 1;
    }
  
    action l2_forward(bit<9> egress_port) {
        standard_metadata.egress_spec = egress_port;
		meta.l2_hit = 1;
    }
	
	action l2_miss() {
		meta.l2_hit = 1;
	}
      
    action set_mcast_group(bit<16> mcast_grp) {
        standard_metadata.mcast_grp = mcast_grp;
    }
      
    action mac_learn() {
        meta.ingress_port = standard_metadata.ingress_port;
        //clone3(CloneType.I2E, 100, meta);
    }
     
    action set_default_vid(bit<12> vid) {
        meta.vid = vid;
    }
      
    action set_vlan(bit<12> vid) {
        meta.vid = vid;
    }
	
	action set_rmac_hit() {
	    meta.rmac_hit = 0;	
	}
      
    table ipv4_lpm {
        key = {
            hdr.ipv4.dstAddr: lpm;
        }
        actions = {
            ipv4_forward;
            drop;
            NoAction;
        }
        size = 1024;
        default_action = NoAction();
    }
    
	table rmac {
	    key = {
			hdr.ethernet.dstAddr:ternary;
		}
		actions = {
			set_rmac_hit;
			NoAction;
		}
		size = 512;
		default_action = NoAction();
	}
	
    table broadcast {
        key = {
            meta.vid:exact;
        }
        actions = {
            set_mcast_group;
            NoAction;
        }
        size = 1024;
        default_action = NoAction();
    }
     
    table dmac {
        key = {
            hdr.ethernet.dstAddr:exact;
            meta.vid:exact;
        }
        actions = {
            l2_forward;
			l2_miss;
            NoAction;
        }
        size = 1024;
        default_action = NoAction();
    }
      
    table smac {
        key = {
            hdr.ethernet.srcAddr:exact;
            meta.vid:exact;
        }
        actions = {
            mac_learn;
            NoAction;
        }
        size = 1024;
        default_action = mac_learn;
    }
      
    table vlan {
        key = {
            hdr.vlan_tag[0].vid:exact;
        }
        actions = {
            set_vlan;
            drop;
            NoAction;
        }
        size = 512;
        default_action = NoAction();
    }
    	
    table port {
        key = {
            standard_metadata.ingress_port:exact;
        }
        actions = {
            set_default_vid;
            NoAction;
        }
        size = 128;
        default_action = NoAction();
    }
      
    apply {
          
        port.apply();
		
        if (hdr.ethernet.isValid()) {
              
            /*报文携带vlan时，使用报文vid*/
            if (hdr.vlan_tag[0].isValid()) {
                vlan.apply();
            }
              
            smac.apply();
            rmac.apply();
			
			if (meta.rmac_hit == 1) {
				ipv4_lpm.apply();
			} else {
				dmac.apply();
			    if (meta.l2_hit == 1) {
                    broadcast.apply();
				}
			}
        }
    }
}
  
/*************************************************************************
****************  E G R E S S   P R O C E S S I N G   *******************
*************************************************************************/
  
control MyEgress(inout headers hdr,
                 inout metadata meta,
                 inout standard_metadata_t standard_metadata) {
    apply {
        if (standard_metadata.instance_type == 1){
            hdr.cpu.setValid();
            hdr.cpu.srcAddr = hdr.ethernet.srcAddr;
            hdr.cpu.ingress_port = (bit<16>)meta.ingress_port;
            hdr.ethernet.etherType = L2_LEARN_ETHER_TYPE;
            truncate((bit<32>)22);
        }
    }
}
  
/*************************************************************************
*************   C H E C K S U M    C O M P U T A T I O N   **************
*************************************************************************/
  
control MyComputeChecksum(inout headers hdr, inout metadata meta) {
     apply {
        update_checksum(
            hdr.ipv4.isValid(),
            { hdr.ipv4.version,
              hdr.ipv4.ihl,
              hdr.ipv4.diffserv,
              hdr.ipv4.totalLen,
              hdr.ipv4.identification,
              hdr.ipv4.flags,
              hdr.ipv4.fragOffset,
              hdr.ipv4.ttl,
              hdr.ipv4.protocol,
              hdr.ipv4.srcAddr,
              hdr.ipv4.dstAddr },
            hdr.ipv4.hdrChecksum,
            HashAlgorithm.csum16);
    }
}
  
  
/*************************************************************************
***********************  D E P A R S E R  *******************************
*************************************************************************/
  
control MyDeparser(packet_out packet, in headers hdr) {
    apply {
        packet.emit(hdr.ethernet);
        packet.emit(hdr.cpu);
        packet.emit(hdr.ipv4);
    }
}
  
/*************************************************************************
***********************  S W I T C H  *******************************
*************************************************************************/
  
V1Switch(
MyParser(),
MyVerifyChecksum(),
MyIngress(),
MyEgress(),
MyComputeChecksum(),
MyDeparser()
) main;