#!/usr/bin/env python import unittest from framework import VppTestCase, VppTestRunner, running_extended_tests from vpp_ip import DpoProto from vpp_ip_route import VppIpRoute, VppRoutePath, \ VppMplsTable, VppIpMRoute, VppMRoutePath, VppIpTable, \ MRouteEntryFlags, MRouteItfFlags, MPLS_LABEL_INVALID, \ VppMplsLabel, FibPathProto, FibPathType from vpp_bier import BIER_HDR_PAYLOAD, VppBierImp, VppBierDispEntry, \ VppBierDispTable, VppBierTable, VppBierTableID, VppBierRoute from vpp_udp_encap import VppUdpEncap import scapy.compat from scapy.packet import Raw from scapy.layers.l2 import Ether from scapy.layers.inet import IP, UDP from scapy.layers.inet6 import IPv6 from scapy.contrib.mpls import MPLS from scapy.contrib.bier import BIER, BIERLength, BIFT NUM_PKTS = 67 class TestBFIB(VppTestCase): """ BIER FIB Test Case """ def test_bfib(self): """ BFIB Unit Tests """ error = self.vapi.cli("test bier") if error: self.logger.critical(error) self.assertNotIn("Failed", error) class TestBier(VppTestCase): """ BIER Test Case """ def setUp(self): super(TestBier, self).setUp() # create 2 pg interfaces self.create_pg_interfaces(range(3)) # create the default MPLS table self.tables = [] tbl = VppMplsTable(self, 0) tbl.add_vpp_config() self.tables.append(tbl) tbl = VppIpTable(self, 10) tbl.add_vpp_config() self.tables.append(tbl) # setup both interfaces for i in self.pg_interfaces: if i == self.pg2: i.set_table_ip4(10) i.admin_up() i.config_ip4() i.resolve_arp() i.enable_mpls() def tearDown(self): for i in self.pg_interfaces: i.disable_mpls() i.unconfig_ip4() i.set_table_ip4(0) i.admin_down() super(TestBier, self).tearDown() def bier_midpoint(self, hdr_len_id, n_bytes, max_bp): """BIER midpoint""" # # Add a BIER table for sub-domain 0, set 0, and BSL 256 # bti = VppBierTableID(0, 0, hdr_len_id) bt = VppBierTable(self, bti, 77) bt.add_vpp_config() # # A packet with no bits set gets dropped # p = (Ether(dst=self.pg0.local_mac, src=self.pg0.remote_mac) / MPLS(label=77, ttl=255) / BIER(length=hdr_len_id) / IPv6(src=self.pg0.remote_ip6, dst=self.pg0.remote_ip6) / UDP(sport=1234, dport=1234) / Raw()) pkts = [p] self.send_and_assert_no_replies(self.pg0, pkts, "Empty Bit-String") # # Add a BIER route for each bit-position in the table via a different # next-hop. Testing whether the BIER walk and replicate forwarding # function works for all bit posisitons. # nh_routes = [] bier_routes = [] for i in range(1, max_bp+1): nh = "10.0.%d.%d" % (i / 255, i % 255) nh_routes.append( VppIpRoute(self, nh, 32, [VppRoutePath(self.pg1.remote_ip4, self.pg1.sw_if_index, labels=[VppMplsLabel(2000+i)])])) nh_routes[-1].add_vpp_config() bier_routes.append( VppBierRoute(self, bti, i, [VppRoutePath(nh, 0xffffffff, labels=[VppMplsLabel(100+i)])])) bier_routes[-1].add_vpp_config() # # A packet with all bits set gets replicated once for each bit # pkt_sizes = [64, 1400] for pkt_size in pkt_sizes: p = (Ether(dst=self.pg0.local_mac, src=self.pg0.remote_mac) / MPLS(label=77, ttl=255) / BIER(length=hdr_len_id, BitString=scapy.compat.chb(255)*n_bytes) / IPv6(src=self.pg0.remote_ip6, dst=self.pg0.remote_ip6) / UDP(sport=1234, dport=1234) / Raw(scapy.compat.chb(5) * pkt_size)) pkts = p self.pg0.add_stream(pkts) self.pg_enable_capture(self.pg_interfaces) self.pg_start() rx = self.pg1.get_capture(max_bp) for rxp in rx: # # The packets are not required to be sent in bit-position order # when we setup the routes above we used the bit-position to # construct the out-label. so use that here to determine the BP # olabel = rxp[MPLS] bp = olabel.label - 2000 blabel = olabel[MPLS].payload self.assertEqual(blabel.label, 100+bp) self.assertEqual(blabel.ttl, 254) bier_hdr = blabel[MPLS].payload self.assertEqual(bier_hdr.id, 5) self.assertEqual(bier_hdr.version, 0) self.assertEqual(bier_hdr.length, hdr_len_id) self.assertEqual(bier_hdr.entropy, 0) self.assertEqual(bier_hdr.OAM, 0) self.assertEqual(bier_hdr.RSV, 0) self.assertEqual(bier_hdr.DSCP, 0) self.assertEqual(bier_hdr.Proto, 5) # The bit-string should consist only of the BP given by i. byte_array = [b'\0'] * (n_bytes) byte_val = scapy.compat.chb(1 << (bp - 1) % 8) byte_pos = n_bytes - (((bp - 1) // 8) + 1) byte_array[byte_pos] = byte_val bitstring = ''.join([scapy.compat.chb(x) for x in byte_array]) self.assertEqual(len(bitstring), len(bier_hdr.BitString)) self.assertEqual(bitstring, bier_hdr.BitString) # # cleanup. not strictly necessary, but it's much quicker this way # because the bier_fib_dump and ip_fib_dump will be empty when the # auto-cleanup kicks in # for br in bier_routes: br.remove_vpp_config() for nhr in nh_routes: nhr.remove_vpp_config() @unittest.skipUnless(running_extended_tests, "part of extended tests") def test_bier_midpoint_1024(self): """BIER midpoint BSL:1024""" self.bier_midpoint(BIERLength.BIER_LEN_1024, 128, 1024) @unittest.skipUnless(running_extended_tests, "part of extended tests") def test_bier_midpoint_512(self): """BIER midpoint BSL:512""" self.bier_midpoint(BIERLength.BIER_LEN_512, 64, 512) @unittest.skipUnless(running_extended_tests, "part of extended tests") def test_bier_midpoint_256(self): """BIER midpoint BSL:256""" self.bier_midpoint(BIERLength.BIER_LEN_256, 32, 256) @unittest.skipUnless(running_extended_tests, "part of extended tests") def test_bier_midpoint_128(self): """BIER midpoint BSL:128""" self.bier_midpoint(BIERLength.BIER_LEN_128, 16, 128) def test_bier_midpoint_64(self): """BIER midpoint BSL:64""" self.bier_midpoint(BIERLength.BIER_LEN_64, 8, 64) def test_bier_load_balance(self): """BIER load-balance""" # # Add a BIER table for sub-domain 0, set 0, and BSL 256 # bti = VppBierTableID(0, 0, BIERLength.BIER_LEN_64) bt = VppBierTable(self, bti, 77) bt.add_vpp_config() # # packets with varying entropy # pkts = [] for ii in range(257): pkts.append((Ether(dst=self.pg0.local_mac, src=self.pg0.remote_mac) / MPLS(label=77, ttl=255) / BIER(length=BIERLength.BIER_LEN_64, entropy=ii, BitString=scapy.compat.chb(255)*16) / IPv6(src=self.pg0.remote_ip6, dst=self.pg0.remote_ip6) / UDP(sport=1234, dport=1234) / Raw())) # # 4 next hops # nhs = [{'ip': "10.0.0.1", 'label': 201}, {'ip': "10.0.0.2", 'label': 202}, {'ip': "10.0.0.3", 'label': 203}, {'ip': "10.0.0.4", 'label': 204}] for nh in nhs: ipr = VppIpRoute( self, nh['ip'], 32, [VppRoutePath(self.pg1.remote_ip4, self.pg1.sw_if_index, labels=[VppMplsLabel(nh['label'])])]) ipr.add_vpp_config() bier_route = VppBierRoute( self, bti, 1, [VppRoutePath(nhs[0]['ip'], 0xffffffff, labels=[VppMplsLabel(101)]), VppRoutePath(nhs[1]['ip'], 0xffffffff, labels=[VppMplsLabel(101)])]) bier_route.add_vpp_config() rx = self.send_and_expect(self.pg0, pkts, self.pg1) # # we should have recieved a packet from each neighbor # for nh in nhs[:2]: self.assertTrue(sum(p[MPLS].label == nh['label'] for p in rx)) # # add the other paths # bier_route.update_paths( [VppRoutePath(nhs[0]['ip'], 0xffffffff, labels=[VppMplsLabel(101)]), VppRoutePath(nhs[1]['ip'], 0xffffffff, labels=[VppMplsLabel(101)]), VppRoutePath(nhs[2]['ip'], 0xffffffff, labels=[VppMplsLabel(101)]), VppRoutePath(nhs[3]['ip'], 0xffffffff, labels=[VppMplsLabel(101)])]) rx = self.send_and_expect(self.pg0, pkts, self.pg1) for nh in nhs: self.assertTrue(sum(p[MPLS].label == nh['label'] for p in rx)) # # remove first two paths # bier_route.remove_path(VppRoutePath(nhs[0]['ip'], 0xffffffff, labels=[VppMplsLabel(101)])) bier_route.remove_path(VppRoutePath(nhs[1]['ip'], 0xffffffff, 
/*
  Copyright (c) 2011 Cisco and/or its affiliates.

  * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at:
 *
 *     http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
*/

#include <vppinfra/anneal.h>

/*
 * Optimize an objective function by simulated annealing
 *
 * Here are a couple of short, easily-understood
 * descriptions of simulated annealing:
 *
 * http://www.cs.sandia.gov/opt/survey/sa.html
 * Numerical Recipes in C, 2nd ed., 444ff
 *
 * The description in the Wikipedia is not helpful.
 *
 * The algorithm tries to produce a decent answer to combinatorially
 * explosive optimization problems by analogy to slow cooling
 * of hot metal, aka annealing.
 *
 * There are (at least) three problem-dependent annealing parameters
 * to consider:
 *
 * t0, the initial "temperature. Should be set so that the probability
 * of accepting a transition to a higher cost configuration is
 * initially about 0.8.
 *
 * ntemps, the number of temperatures to use. Each successive temperature
 * is some fraction of the previous temperature.
 *
 * nmoves_per_temp, the number of configurations to try at each temperature
 *
 * It is a black art to set ntemps, nmoves_per_temp, and the rate
 * at which the temperature drops. Go too fast with too few iterations,
 * and the computation falls into a local minimum instead of the
 * (desired) global minimum.
 */

void
clib_anneal (clib_anneal_param_t * p)
{
  f64 t;
  f64 cost, prev_cost, delta_cost, initial_cost, best_cost;
  f64 random_accept, delta_cost_over_t;
  f64 total_increase = 0.0, average_increase;
  u32 i, j;
  u32 number_of_increases = 0;
  u32 accepted_this_temperature;
  u32 best_saves_this_temperature;
  int accept;

  t = p->initial_temperature;
  best_cost = initial_cost = prev_cost = p->anneal_metric (p->opaque);
  p->anneal_save_best_configuration (p->opaque);

  if (p->flags & CLIB_ANNEAL_VERBOSE)
    fformat (stdout, "Initial cost %.2f\n", initial_cost);

  for (i = 0; i < p->number_of_temperatures; i++)
    {
      accepted_this_temperature = 0;
      best_saves_this_temperature = 0;

      p->anneal_restore_best_configuration (p->opaque);
      cost = best_cost;

      for (j = 0; j < p->number_of_configurations_per_temperature; j++)
	{
	  p->anneal_new_configuration (p->opaque);
	  cost = p->anneal_metric (p->opaque);

	  delta_cost = cost - prev_cost;

	  /* cost function looks better, accept this move */
	  if (p->flags & CLIB_ANNEAL_MINIMIZE)
	    accept = delta_cost < 0.0;
	  else
	    accept = delta_cost > 0.0;

	  if (accept)
	    {
	      if (p->flags & CLIB_ANNEAL_MINIMIZE)
		if (cost < best_cost)
		  {
		    if (p->flags & CLIB_ANNEAL_VERBOSE)
		      fformat (stdout, "New best cost %.2f\n", cost);
		    best_cost = cost;
		    p->anneal_save_best_configuration (p->opaque);
		    best_saves_this_temperature++;
		  }

	      accepted_this_temperature++;
	      prev_cost = cost;
	      continue;
	    }

	  /* cost function worse, keep stats to suggest t0 */
	  total_increase += (p->flags & CLIB_ANNEAL_MINIMIZE) ?
	    delta_cost : -delta_cost;

	  number_of_increases++;

	  /*
	   * Accept a higher cost with Pr { e^(-(delta_cost / T)) },
	   * equivalent to rnd[0,1] < e^(-(delta_cost / T))
	   *
	   * AKA, the Boltzmann factor.
	   */
	  random_accept = ra