Rework vlan example to be 1:1, no mac learning

* Use ifindex instead of src_mac to program egress table
* Remove the static arp programming
* Get the example to work in python2

Signed-off-by: Brenden Blanco <[email protected]>

examples/hello_world.py

@@ -2,8 +2,8 @@
 # Copyright (c) PLUMgrid, Inc.
 # Licensed under the Apache License, Version 2.0 (the "License")
 
-# run in project directory with:
-# sudo bash -c "PYTHONPATH=$PWD/src LD_LIBRARY_PATH=$PWD/build/src/cc examples/hello_world.py"
+# run in project examples directory with:
+# sudo ./hello_world.py"
 
 from bpf import BPF
 from subprocess import call

examples/vlan_learning.c

@@ -10,7 +10,7 @@ struct ifindex_leaf_t {
 };
 
 // redirect based on mac -> out_ifindex (auto-learning)
-BPF_TABLE("hash", u64, struct ifindex_leaf_t, egress, 4096);
+BPF_TABLE("hash", int, struct ifindex_leaf_t, egress, 4096);
 
 // redirect based on mac -> out_ifindex (config-driven)
 BPF_TABLE("hash", u64, struct ifindex_leaf_t, ingress, 4096);
@@ -24,8 +24,9 @@ int handle_phys2virt(struct __sk_buff *skb) {
  lock_xadd(&leaf->tx_pkts, 1);
  lock_xadd(&leaf->tx_bytes, skb->len);
  // auto-program reverse direction table
+ int out_ifindex = leaf->out_ifindex;
  struct ifindex_leaf_t zleaf = {0};
- struct ifindex_leaf_t *out_leaf = egress.lookup_or_init(&src_mac, &zleaf);
+ struct ifindex_leaf_t *out_leaf = egress.lookup_or_init(&out_ifindex, &zleaf);
  // relearn when mac moves ifindex
  if (out_leaf->out_ifindex != skb->ifindex)
  out_leaf->out_ifindex = skb->ifindex;
@@ -39,8 +40,8 @@ int handle_phys2virt(struct __sk_buff *skb) {
 int handle_virt2phys(struct __sk_buff *skb) {
  BEGIN(ethernet);
  PROTO(ethernet) {
- u64 dst_mac = ethernet->dst;
- struct ifindex_leaf_t *leaf = egress.lookup(&dst_mac);
+ int src_ifindex = skb->ifindex;
+ struct ifindex_leaf_t *leaf = egress.lookup(&src_ifindex);
  if (leaf) {
  lock_xadd(&leaf->tx_pkts, 1);
  lock_xadd(&leaf->tx_bytes, skb->len);

examples/vlan_learning.py

@@ -24,6 +24,7 @@
 # switch | subinterface |
 
 from bpf import BPF
+from builtins import input
 from ctypes import c_uint, c_int, c_ulonglong, Structure
 from pyroute2 import IPRoute, NetNS, IPDB, NSPopen
 from random import shuffle
@@ -34,8 +35,7 @@
 ipr = IPRoute()
 ipdb = IPDB(nl=ipr)
 
-num_workers = 3
-num_clients = 9
+num_clients = 3
 num_vlans = 16
 
 # load the bpf program
@@ -52,7 +52,7 @@ def __init__(self, ipdb):
 
  def start(self):
  # start identical workers each in a namespace
- for i in range(0, num_workers):
+ for i in range(0, num_clients):
  httpmod = ("SimpleHTTPServer" if sys.version_info[0] < 3
  else "http.server")
  cmd = ["python", "-m", httpmod, "80"]
@@ -84,32 +84,27 @@ def start(self):
  # allocate vlans randomly
  available_vlans = [i for i in range(2, 2 + num_vlans)]
  shuffle(available_vlans)
- available_ips = [[i for i in range(100, 105)] for i in range(0, num_workers)]
+ available_ips = [[i for i in range(100, 105)] for i in range(0, num_clients)]
 
  # these are simulations of physical clients
  for i in range(0, num_clients):
- worker_i = i % num_workers
- ipaddr = "172.16.1.%d" % available_ips[worker_i].pop(0)
  macaddr = ("02:00:00:%.2x:%.2x:%.2x" %
  ((i >> 16) & 0xff, (i >> 8) & 0xff, i & 0xff))
 
- # program arp manually
- p = NSPopen("worker%d" % worker_i, ["arp", "-s", ipaddr, macaddr])
- p.communicate(); p.wait(); p.release()
-
  # assign this client to the given worker
- idx = self.ipdb.interfaces["worker%da" % worker_i]["index"]
+ idx = self.ipdb.interfaces["worker%da" % i]["index"]
  mac = int(macaddr.replace(":", ""), 16)
  ingress[ingress.Key(mac)] = ingress.Leaf(idx, 0, 0)
 
  # test traffic with curl loop
  cmd = ["bash", "-c",
  "for i in {1..8}; do curl 172.16.1.5 -o /dev/null; sleep 1; done"]
- br_ifc = self.ipdb.create(ifname="br100.%d" % i, kind="vlan", link=br100,
+ br_ifc = self.ipdb.create(ifname="br100.%d" % i, kind="vlan",
+ link=br100,
  vlan_id=available_vlans.pop(0)).commit()
  (out_ifc, in_ifc) = self._create_ns("client%d" % i, in_ifc=br_ifc,
- ipaddr=ipaddr + "/24", macaddr=macaddr,
- cmd=cmd)[1:3]
+ ipaddr="172.16.1.100/24",
+ macaddr=macaddr, cmd=cmd)[1:3]
 
 try:
  sim = VlanSimulation(ipdb)