Hello, I've been having a problem for days, I can not capture tcp packets
with the controller.
My topology is below:
+---------------------------+
| |
| C0 - Controller |
| |
+-------------+-------------+
c0-eth0
|
|
+-+--+--+-+ +-+--+--+
| Switch | ---------------- | H2 |
+-+--+--+-+ +-+--+--+
|
|
s1-eth0.2
+-------------+-------------+------+
| |
| S1 - OpenFlow AP |
| |
| |
+-+----------+----------+---+
s1-eth0.1
+
|
|
v
h1-eth0
+-+--+
| H1 |
+-+--+
I want to modify tcp packets sent by server h1 to another h2 server
connected to the common switch, but when I print the packages, there is no
tcp package, just other types of packages like udp, dhcp, igmp, ipv4, ipv6. I
have no idea why, I'd like the opinion of you.
My code is below, just an example to test here:
from ryu.base import app_manager
# from ryu.ofproto import ofproto_v1_0
from ryu.ofproto import ofproto_v1_5
from ryu.lib.packet import packet
from ryu.lib.packet import ethernet
from ryu.lib.packet import ipv4
from ryu.lib.packet import tcp
from ryu.controller import ofp_event
from ryu.controller.handler import MAIN_DISPATCHER, CONFIG_DISPATCHER
from ryu.controller.handler import set_ev_cls
from ryu.topology import event
#iperf tcp example
class L2Forwarding(app_manager.RyuApp):
# OFP_VERSIONS = [ofproto_v1_0.OFP_VERSION]
OFP_VERSIONS = [ofproto_v1_5.OFP_VERSION]
def __init__(self, *args, **kwargs):
super(L2Forwarding, self).__init__(*args, **kwargs)
@set_ev_cls(ofp_event.EventOFPSwitchFeatures, CONFIG_DISPATCHER)
def switch_features_handler(self, ev):
datapath = ev.msg.datapath
ofproto = datapath.ofproto
parser = datapath.ofproto_parser
print("install the table-miss flow entry")
# install the table-miss flow entry.
match = parser.OFPMatch()
actions = [parser.OFPActionOutput(ofproto.OFPP_CONTROLLER,
ofproto.OFPCML_NO_BUFFER)]
self.add_flow(datapath, 0, match, actions)
def add_flow(self, datapath, priority, match, actions):
ofproto = datapath.ofproto
parser = datapath.ofproto_parser
print("construct flow_mod message and send it")
# construct flow_mod message and send it.
inst = [parser.OFPInstructionActions(ofproto.OFPIT_APPLY_ACTIONS,
actions)]
mod = parser.OFPFlowMod(datapath=datapath, priority=priority,
match=match, instructions=inst)
datapath.send_msg(mod)
@set_ev_cls(ofp_event.EventOFPPacketIn, MAIN_DISPATCHER)
def packet_in_handler(self, ev):
msg = ev.msg # Object representing a packet_in data
structure.
datapath = msg.datapath # Switch Datapath ID
ofproto = datapath.ofproto # OpenFlow Protocol version the entities
negotiated. In our case OF1.3
parser = datapath.ofproto_parser
out_port = ofproto.OFPP_LOCAL
in_port = ofproto.OFPP_LOCAL
pkt = packet.Packet(msg.data)
eth = pkt.get_protocol(ethernet.ethernet)
dst = eth.dst
src = eth.src
print(pkt.get_protocol)
self.logger.info("packet in %s %s", src, dst)
v4 = pkt.get_protocol(ipv4.ipv4)
if v4:
print("IPV4: %s ==> %s " % (v4.src, v4.dst))
server_ip = v4.dst
in_port = msg.match['in_port']
if pkt.get_protocol(tcp.tcp):
src_port = pkt.src_port
print("TCP GET %s", "=" * 100)
#Match in protocol tcp "in_proto=6" and ipv4
"eth_type=0x0800"
match_tcp = parser.OFPMatch(in_port=in_port,
eth_type=0x0800, ip_proto=6, tcp_flags=0x010, ipv4_dst=server_ip,
tcp_src=src_port)
actions =
[datapath.ofproto_parser.OFPActionOutput(out_port)]
self.add_flow(datapath, 1, match_tcp, actions)
------------------------------------------------------------------------------
Check out the vibrant tech community on one of the world's most
engaging tech sites, Slashdot.org! http://sdm.link/slashdot
_______________________________________________
Ryu-devel mailing list
Ryu-devel@lists.sourceforge.net
https://lists.sourceforge.net/lists/listinfo/ryu-devel
