페이지 이력

#!/usr/bin/env python3
import argparse
import os
import sys
from time import sleep

import grpc

# Import P4Runtime lib from parent utils dir
# Probably there's a better way of doing this.
sys.path.append(
    os.path.join(os.path.dirname(os.path.abspath(__file__)),
                 '../../utils/'))
import p4runtime_lib.bmv2
import p4runtime_lib.helper
from p4runtime_lib.switch import ShutdownAllSwitchConnections

SWITCH_TO_HOST_PORT = 1
SWITCH_TO_SWITCH_PORT = 2


def writeTunnelRules(p4info_helper, ingress_sw, egress_sw, tunnel_id,
                     dst_eth_addr, dst_ip_addr):
    """
    Installs three rules:
    1) An tunnel ingress rule on the ingress switch in the ipv4_lpm table that
       encapsulates traffic into a tunnel with the specified ID
    2) A transit rule on the ingress switch that forwards traffic based on
       the specified ID
    3) An tunnel egress rule on the egress switch that decapsulates traffic
       with the specified ID and sends it to the host

    :param p4info_helper: the P4Info helper
    :param ingress_sw: the ingress switch connection
    :param egress_sw: the egress switch connection
    :param tunnel_id: the specified tunnel ID
    :param dst_eth_addr: the destination Ethernet address to write in the
                        egress rule
    :param dst_ip_addr: the destination IP to match in the ingress rule
    """
    # 1) Tunnel Ingress Rule -> 패킷이 스위치에 들어올 때의 규칙을 ipv4 테이블에 설정한다. 즉, s1에 들어오는 각각의 패킷의 ipv4Addr에 맞는 action을 지정한다. 여기서는 패킷이 이동할 터널의 id를 myTunnel_ingress action에 전달한다.
    table_entry = p4info_helper.buildTableEntry(
        table_name="MyIngress.ipv4_lpm",
        match_fields={
            "hdr.ipv4.dstAddr": (dst_ip_addr, 32)
        },
        action_name="MyIngress.myTunnel_ingress",
        action_params={
            "dst_id": tunnel_id,
        })
    ingress_sw.WriteTableEntry(table_entry)
    print("Installed ingress tunnel rule on %s" % ingress_sw.name)

    # 2) Tunnel Transit Rule
    # The rule will need to be added to the myTunnel_exact table and match on
    # the tunnel ID (hdr.myTunnel.dst_id). Traffic will need to be forwarded
    # using the myTunnel_forward action on the port connected to the next switch.
    #
    # For our simple topology, switch 1 and switch 2 are connected using a
    # link attached to port 2 on both switches. We have defined a variable at
    # the top of the file, SWITCH_TO_SWITCH_PORT, that you can use as the output
    # port for this action.
    #
    # We will only need a transit rule on the ingress switch because we are
    # using a simple topology. In general, you'll need on transit rule for
    # each switch in the path (except the last switch, which has the egress rule),
    # and you will need to select the port dynamically for each switch based on
    # your topology.

    # TODO build the transit rule
    # TODO install the transit rule on the ingress switch
    table_entry = p4info_helper.buildTableEntry( #tunnel 테이블에 규칙을 추가한다. 여기서는 tunnel헤더의 tunnel_id를 보고 패킷이 전송될 port를 지정해준다.
        table_name="MyIngress.myTunnel_exact",
        match_fields={
            "hdr.myTunnel.dst_id": tunnel_id
        },
        action_name="MyIngress.myTunnel_forward",
        action_params={
            "port": SWITCH_TO_SWITCH_PORT
        })
    ingress_sw.WriteTableEntry(table_entry)
    print("Installed transit tunnel rule on %s" % ingress_sw.name)

    # 3) Tunnel Egress Rule
    # For our simple topology, the host will always be located on the
    # SWITCH_TO_HOST_PORT (port 1).
    # In general, you will need to keep track of which port the host is
    # connected to.
    table_entry = p4info_helper.buildTableEntry( # tunnel을 모두 통과하고 호스트로 패킷을 전달할 때 tunnel 헤더의 tunnel_id에 따른 목적지 호스트의 ipAddr과 연결된 port를 지정해준다.
        table_name="MyIngress.myTunnel_exact",
        match_fields={
            "hdr.myTunnel.dst_id": tunnel_id
        },
        action_name="MyIngress.myTunnel_egress",
        action_params={
            "dstAddr": dst_eth_addr,
            "port": SWITCH_TO_HOST_PORT
        })
    egress_sw.WriteTableEntry(table_entry)
    print("Installed egress tunnel rule on %s" % egress_sw.name)


def readTableRules(p4info_helper, sw):
    """
    Reads the table entries from all tables on the switch.

    :param p4info_helper: the P4Info helper
    :param sw: the switch connection
    """
    print('\n----- Reading tables rules for %s -----' % sw.name)
    for response in sw.ReadTableEntries():
        for entity in response.entities:
            entry = entity.table_entry
            # TODO For extra credit, you can use the p4info_helper to translate
            #      the IDs in the entry to names
            table_name = p4info_helper.get_tables_name(entry.table_id)
            print('%s: ' % table_name, end=' ')
            for m in entry.match:
                print(p4info_helper.get_match_field_name(table_name, m.field_id), end=' ')
                print('%r' % (p4info_helper.get_match_field_value(m),), end=' ')
            action = entry.action.action
            action_name = p4info_helper.get_actions_name(action.action_id)
            print('->', action_name, end=' ')
            for p in action.params:
                print(p4info_helper.get_action_param_name(action_name, p.param_id), end=' ')
                print('%r' % p.value, end=' ')
            print()

def printCounter(p4info_helper, sw, counter_name, index):
    """
    Reads the specified counter at the specified index from the switch. In our
    program, the index is the tunnel ID. If the index is 0, it will return all
    values from the counter.

    :param p4info_helper: the P4Info helper
    :param sw:  the switch connection
    :param counter_name: the name of the counter from the P4 program
    :param index: the counter index (in our case, the tunnel ID)
    """
    for response in sw.ReadCounters(p4info_helper.get_counters_id(counter_name), index):
        for entity in response.entities:
            counter = entity.counter_entry
            print("%s %s %d: %d packets (%d bytes)" % (
                sw.name, counter_name, index,
                counter.data.packet_count, counter.data.byte_count
            ))

def printGrpcError(e):
    print("gRPC Error:", e.details(), end=' ')
    status_code = e.code()
    print("(%s)" % status_code.name, end=' ')
    traceback = sys.exc_info()[2]
    print("[%s:%d]" % (traceback.tb_frame.f_code.co_filename, traceback.tb_lineno))

def main(p4info_file_path, bmv2_file_path):
    # Instantiate a P4Runtime helper from the p4info file
    p4info_helper = p4runtime_lib.helper.P4InfoHelper(p4info_file_path)

    try:
        # Create a switch connection object for s1 and s2;
        # this is backed by a P4Runtime gRPC connection.
        # Also, dump all P4Runtime messages sent to switch to given txt files.
        s1 = p4runtime_lib.bmv2.Bmv2SwitchConnection(                     
            name='s1',
            address='127.0.0.1:50051',
            device_id=0,
            proto_dump_file='logs/s1-p4runtime-requests.txt')
        s2 = p4runtime_lib.bmv2.Bmv2SwitchConnection(
            name='s2',
            address='127.0.0.1:50052',
            device_id=1,
            proto_dump_file='logs/s2-p4runtime-requests.txt')

        # Send master arbitration update message to establish this controller as
        # master (required by P4Runtime before performing any other write operation)
        s1.MasterArbitrationUpdate()
        s2.MasterArbitrationUpdate()

        # Install the P4 program on the switches
        s1.SetForwardingPipelineConfig(p4info=p4info_helper.p4info,
                                       bmv2_json_file_path=bmv2_file_path)
        print("Installed P4 Program using SetForwardingPipelineConfig on s1")
        s2.SetForwardingPipelineConfig(p4info=p4info_helper.p4info,
                                       bmv2_json_file_path=bmv2_file_path)
        print("Installed P4 Program using SetForwardingPipelineConfig on s2")

        # Write the rules that tunnel traffic from h1 to h2
        writeTunnelRules(p4info_helper, ingress_sw=s1, egress_sw=s2, tunnel_id=100,
                         dst_eth_addr="08:00:00:00:02:22", dst_ip_addr="10.0.2.2")

        # Write the rules that tunnel traffic from h2 to h1
        writeTunnelRules(p4info_helper, ingress_sw=s2, egress_sw=s1, tunnel_id=200,
                         dst_eth_addr="08:00:00:00:01:11", dst_ip_addr="10.0.1.1")

        # TODO Uncomment the following two lines to read table entries from s1 and s2
        readTableRules(p4info_helper, s1)
        readTableRules(p4info_helper, s2)

        # Print the tunnel counters every 2 seconds
        while True:
            sleep(2)
            print('\n----- Reading tunnel counters -----')
            printCounter(p4info_helper, s1, "MyIngress.ingressTunnelCounter", 100)
            printCounter(p4info_helper, s2, "MyIngress.egressTunnelCounter", 100)
            printCounter(p4info_helper, s2, "MyIngress.ingressTunnelCounter", 200)
            printCounter(p4info_helper, s1, "MyIngress.egressTunnelCounter", 200)

    except KeyboardInterrupt:
        print(" Shutting down.")
    except grpc.RpcError as e:
        printGrpcError(e)

    ShutdownAllSwitchConnections()

if __name__ == '__main__':
    parser = argparse.ArgumentParser(description='P4Runtime Controller')
    parser.add_argument('--p4info', help='p4info proto in text format from p4c',
                        type=str, action="store", required=False,
                        default='./build/advanced_tunnel.p4.p4info.txt')
    parser.add_argument('--bmv2-json', help='BMv2 JSON file from p4c',
                        type=str, action="store", required=False,
                        default='./build/advanced_tunnel.json')
    args = parser.parse_args()

    if not os.path.exists(args.p4info):
        parser.print_help()
        print("\np4info file not found: %s\nHave you run 'make'?" % args.p4info)
        parser.exit(1)
    if not os.path.exists(args.bmv2_json):
        parser.print_help()
        print("\nBMv2 JSON file not found: %s\nHave you run 'make'?" % args.bmv2_json)
        parser.exit(1)
    main(args.p4info, args.bmv2_json)

/* -*- P4_16 -*- */
#include <core.p4>
#include <v1model.p4>

const bit<8>  UDP_PROTOCOL = 0x11;
const bit<16> TYPE_IPV4 = 0x800;
const bit<5>  IPV4_OPTION_MRI = 31;

#define MAX_HOPS 9

/*************************************************************************
*********************** H E A D E R S  ***********************************
*************************************************************************/

typedef bit<9>  egressSpec_t;
typedef bit<48> macAddr_t;
typedef bit<32> ip4Addr_t;
typedef bit<32> switchID_t;
typedef bit<32> qdepth_t;

header ethernet_t {
    macAddr_t dstAddr;
    macAddr_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;
    ip4Addr_t srcAddr;
    ip4Addr_t dstAddr;
}
//ipv4 헤더에 옵션을 추가한다. 이는 이 패킷에 mri를 추가하겠다는 의미를 내포할 수 있게된다.
header ipv4_option_t {
    bit<1> copyFlag;
    bit<2> optClass;
    bit<5> option;
    bit<8> optionLength;
}
//mri 개수를 저장한다.
header mri_t {
    bit<16>  count;
}
//지나온 스위치의 id와 해당 스위치에서 패킷이 빠져나올때 남아있는 대기열의 깊이를 저장한다.
header switch_t {
    switchID_t  swid;//지나온 스위치의 id
    qdepth_t    qdepth;//스위치에서 패킷이 빠져나올때 남아있는 대기열의 깊이
}

struct ingress_metadata_t {
    bit<16>  count;
}

struct parser_metadata_t {
    bit<16>  remaining;
}
//추가적인 메타데이터 구조체
struct metadata {
    ingress_metadata_t   ingress_metadata;
    parser_metadata_t   parser_metadata;
}
//완성된 패킷의 전체 헤더
struct headers {
    ethernet_t         ethernet;
    ipv4_t             ipv4;
    ipv4_option_t      ipv4_option;//mri는 ipv4의 option으로 저장된다. 즉 ipv4헤더에 포함된다.
    mri_t              mri;
    switch_t[MAX_HOPS] swtraces;//최대 MAX_HOPS개의 경로를 저장할 수 있다.
}

error { IPHeaderTooShort }

/*************************************************************************
*********************** 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 {
        transition parse_ethernet;
    }

    state parse_ethernet {
        packet.extract(hdr.ethernet);
        transition select(hdr.ethernet.etherType) {
            TYPE_IPV4: parse_ipv4;
            default: accept;
        }
    }

    state parse_ipv4 {
        packet.extract(hdr.ipv4);
        verify(hdr.ipv4.ihl >= 5, error.IPHeaderTooShort);
        transition select(hdr.ipv4.ihl) {
            5             : accept;
            default       : parse_ipv4_option;
        }
    }

    state parse_ipv4_option {
        packet.extract(hdr.ipv4_option);
        transition select(hdr.ipv4_option.option) {
            IPV4_OPTION_MRI: parse_mri;
            default: accept;
        }
    }

    state parse_mri {
        packet.extract(hdr.mri);
		//헤더의 mri의 개수를 읽어온다. 
        meta.parser_metadata.remaining = hdr.mri.count;
        transition select(meta.parser_metadata.remaining) {//mri가 1개라도 있다면 mri를 추출하기 위해 parse_swtrace 상태로 전이한다.
            0 : accept;
            default: parse_swtrace;
        }
    }

    state parse_swtrace {
        packet.extract(hdr.swtraces.next);//경로를 추출한다.
        meta.parser_metadata.remaining = meta.parser_metadata.remaining  - 1;//추출할 mri의 개수를 1씩 줄인다. 
        transition select(meta.parser_metadata.remaining) {//추출할 mri가 남아있다면 재귀적으로 계속 추출한다.
            0 : accept;
            default: parse_swtrace;
        }
    }
}


/*************************************************************************
************   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;
    }

    table ipv4_lpm {
        key = {
            hdr.ipv4.dstAddr: lpm;
        }
        actions = {
            ipv4_forward;
            drop;
            NoAction;
        }
        size = 1024;
        default_action = NoAction();
    }

    apply {
        if (hdr.ipv4.isValid()) {
            ipv4_lpm.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) {
	//스위치에서 패킷이 나갈때 mri를 추가한다.
    action add_swtrace(switchID_t swid) {
        hdr.mri.count = hdr.mri.count + 1;//mri 개수 증가
        hdr.swtraces.push_front(1);//맨앞에 mri추가
        // According to the P4_16 spec, pushed elements are invalid, so we need
        // to call setValid(). Older bmv2 versions would mark the new header(s)
        // valid automatically (P4_14 behavior), but starting with version 1.11,
        // bmv2 conforms with the P4_16 spec.
        hdr.swtraces[0].setValid();
        hdr.swtraces[0].swid = swid;//추가한 mri에 스위치 id 설정
        hdr.swtraces[0].qdepth = (qdepth_t)standard_metadata.deq_qdepth;//추가한 mri에 대기열의 남아있는 깊이를 설정

        hdr.ipv4.ihl = hdr.ipv4.ihl + 2;//ipv4헤더가 총 8byte 증가 했기 때문에 ihl값을 2만큼 증가시킨다.
        hdr.ipv4_option.optionLength = hdr.ipv4_option.optionLength + 8;//ipv4 옵션이 총 8byte 증가 했기 때문에 8만큼 증가시킨다.
        hdr.ipv4.totalLen = hdr.ipv4.totalLen + 8;//ipv4 헤더 + 데이터가 총 8byte 증가 했기 때문에 8만큼 증가시킨다.
    }

    table swtrace {
        actions = {
            add_swtrace;
            NoAction;
        }
        default_action = NoAction();
    }

    apply {
        if (hdr.mri.isValid()) {//mri가 유효하다면 실행한다.
            swtrace.apply();
        }
    }
}

/*************************************************************************
*************   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.ipv4);
        packet.emit(hdr.ipv4_option);
        packet.emit(hdr.mri);
        packet.emit(hdr.swtraces);
    }
}

/*************************************************************************
***********************  S W I T C H  *******************************
*************************************************************************/

V1Switch(
MyParser(),
MyVerifyChecksum(),
MyIngress(),
MyEgress(),
MyComputeChecksum(),
MyDeparser()
) main;

/* -*- P4_16 -*- */
#include <core.p4>
#include <v1model.p4>

const bit<16> TYPE_IPV4 = 0x800;
const bit<16> TYPE_SRCROUTING = 0x1234;

#define MAX_HOPS 9

/*************************************************************************
*********************** 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;
}
//패킷의 이동 경로를 저장할 헤더이다.
header srcRoute_t {
    bit<1>    bos;
    bit<15>   port;
}

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 */
}
//패킷 헤더에 패킷 경로 헤더를 추가
struct headers {
    ethernet_t              ethernet;
    srcRoute_t[MAX_HOPS]    srcRoutes;
    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 {
        transition parse_ethernet;
    }

    state parse_ethernet {
        packet.extract(hdr.ethernet);
        transition select(hdr.ethernet.etherType) {
            TYPE_SRCROUTING: parse_srcRouting;
            default: accept;
        }
    }
	//소스라우팅 헤더가 있다면 bos(스택의 바닥)까지 경로를 추출한다.
    state parse_srcRouting {
        packet.extract(hdr.srcRoutes.next);
        transition select(hdr.srcRoutes.last.bos) {
            1: parse_ipv4;
            default: parse_srcRouting;
        }
    }

    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);
    }
	//소스라우팅 헤더의 스택에서 경로 하나를 pop한다.
    action srcRoute_nhop() {
        standard_metadata.egress_spec = (bit<9>)hdr.srcRoutes[0].port;
        hdr.srcRoutes.pop_front(1);
    }
	//패킷에 지정한 모든 경로를 다 돌았다면 패킷 헤더(이더넷 헤더타입)을 ipv4로 바꾼다.
    action srcRoute_finish() {
        hdr.ethernet.etherType = TYPE_IPV4;
    }

    action update_ttl(){
        hdr.ipv4.ttl = hdr.ipv4.ttl - 1;
    }

    apply {
        if (hdr.srcRoutes[0].isValid()){
            if (hdr.srcRoutes[0].bos == 1){//이번 경로가 마지막이라면 패킷을 ipv4로 바꾼다.
                srcRoute_finish();
            }
            srcRoute_nhop();//경로를 pop
            if (hdr.ipv4.isValid()){
                update_ttl();
            }
        }else{
            drop();
        }
    }
}

/*************************************************************************
****************  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 {  }
}

/*************************************************************************
*************   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 {  }
}

/*************************************************************************
***********************  D E P A R S E R  *******************************
*************************************************************************/

control MyDeparser(packet_out packet, in headers hdr) {
    apply {
        packet.emit(hdr.ethernet);
        packet.emit(hdr.srcRoutes);
        packet.emit(hdr.ipv4);
    }
}

/*************************************************************************
***********************  S W I T C H  *******************************
*************************************************************************/

V1Switch(
MyParser(),
MyVerifyChecksum(),
MyIngress(),
MyEgress(),
MyComputeChecksum(),
MyDeparser()
) main;