test/vpp_pg_interface.py

   1 import os
   2 import time
   3 from logging import error, info
   4 from scapy.utils import wrpcap, rdpcap
   5 from vpp_interface import VppInterface
   6
   7 from scapy.layers.l2 import Ether, ARP
   8 from scapy.layers.inet6 import IPv6, ICMPv6ND_NS, ICMPv6ND_NA, \
   9     ICMPv6NDOptSrcLLAddr, ICMPv6NDOptDstLLAddr
  10
  11
  12 class VppPGInterface(VppInterface):
  13     """
  14     VPP packet-generator interface
  15     """
  16
  17     @property
  18     def pg_index(self):
  19         """packet-generator interface index assigned by VPP"""
  20         return self._pg_index
  21
  22     @property
  23     def out_path(self):
  24         """pcap file path - captured packets"""
  25         return self._out_path
  26
  27     @property
  28     def in_path(self):
  29         """ pcap file path - injected packets"""
  30         return self._in_path
  31
  32     @property
  33     def capture_cli(self):
  34         """CLI string to start capture on this interface"""
  35         return self._capture_cli
  36
  37     @property
  38     def cap_name(self):
  39         """capture name for this interface"""
  40         return self._cap_name
  41
  42     @property
  43     def input_cli(self):
  44         """CLI string to load the injected packets"""
  45         return self._input_cli
  46
  47     @property
  48     def in_history_counter(self):
  49         """Self-incrementing counter used when renaming old pcap files"""
  50         v = self._in_history_counter
  51         self._in_history_counter += 1
  52         return v
  53
  54     @property
  55     def out_history_counter(self):
  56         """Self-incrementing counter used when renaming old pcap files"""
  57         v = self._out_history_counter
  58         self._out_history_counter += 1
  59         return v
  60
  61     def post_init_setup(self):
  62         """ Perform post-init setup for super class and add our own setup """
  63         super(VppPGInterface, self).post_init_setup()
  64         self._out_file = "pg%u_out.pcap" % self.pg_index
  65         self._out_path = self.test.tempdir + "/" + self._out_file
  66         self._in_file = "pg%u_in.pcap" % self.pg_index
  67         self._in_path = self.test.tempdir + "/" + self._in_file
  68         self._capture_cli = "packet-generator capture pg%u pcap %s" % (
  69             self.pg_index, self.out_path)
  70         self._cap_name = "pcap%u" % self.sw_if_index
  71         self._input_cli = "packet-generator new pcap %s source pg%u name %s" % (
  72             self.in_path, self.pg_index, self.cap_name)
  73
  74     def __init__(self, test, pg_index):
  75         """ Create VPP packet-generator interface """
  76         self._in_history_counter = 0
  77         self._out_history_counter = 0
  78         self._pg_index = pg_index
  79         self._test = test
  80         r = self.test.vapi.pg_create_interface(self.pg_index)
  81         self._sw_if_index = r.sw_if_index
  82         self.post_init_setup()
  83
  84     def enable_capture(self):
  85         """ Enable capture on this packet-generator interface"""
  86         try:
  87             if os.path.isfile(self.out_path):
  88                 os.rename(self.out_path,
  89                           "%s/history.[timestamp:%f].[%s-counter:%04d].%s" %
  90                           (self.test.tempdir,
  91                            time.time(),
  92                            self.name,
  93                            self.out_history_counter,
  94                            self._out_file))
  95         except:
  96             pass
  97         # FIXME this should be an API, but no such exists atm
  98         self.test.vapi.cli(self.capture_cli)
  99
 100     def add_stream(self, pkts):
 101         """
 102         Add a stream of packets to this packet-generator
 103
 104         :param pkts: iterable packets
 105
 106         """
 107         try:
 108             if os.path.isfile(self.in_path):
 109                 os.rename(self.in_path,
 110                           "%s/history.[timestamp:%f].[%s-counter:%04d].%s" %
 111                           (self.test.tempdir,
 112                            time.time(),
 113                            self.name,
 114                            self.in_history_counter,
 115                            self._in_file))
 116         except:
 117             pass
 118         wrpcap(self.in_path, pkts)
 119         # FIXME this should be an API, but no such exists atm
 120         self.test.vapi.cli(self.input_cli)
 121         self.test.pg_streams.append(self.cap_name)
 122         self.test.vapi.cli("trace add pg-input %d" % len(pkts))
 123
 124     def get_capture(self):
 125         """
 126         Get captured packets
 127
 128         :returns: iterable packets
 129         """
 130         try:
 131             output = rdpcap(self.out_path)
 132         except IOError:  # TODO
 133             error("File %s does not exist, probably because no"
 134                   " packets arrived" % self.out_path)
 135             return []
 136         return output
 137
 138     def create_arp_req(self):
 139         """Create ARP request applicable for this interface"""
 140         return (Ether(dst="ff:ff:ff:ff:ff:ff", src=self.remote_mac) /
 141                 ARP(op=ARP.who_has, pdst=self.local_ip4,
 142                     psrc=self.remote_ip4, hwsrc=self.remote_mac))
 143
 144     def create_ndp_req(self):
 145         """Create NDP - NS applicable for this interface"""
 146         return (Ether(dst="ff:ff:ff:ff:ff:ff", src=self.remote_mac) /
 147                 IPv6(src=self.remote_ip6, dst=self.local_ip6) /
 148                 ICMPv6ND_NS(tgt=self.local_ip6) /
 149                 ICMPv6NDOptSrcLLAddr(lladdr=self.remote_mac))
 150
 151     def resolve_arp(self, pg_interface=None):
 152         """Resolve ARP using provided packet-generator interface
 153
 154         :param pg_interface: interface used to resolve, if None then this
 155             interface is used
 156
 157         """
 158         if pg_interface is None:
 159             pg_interface = self
 160         info("Sending ARP request for %s on port %s" %
 161              (self.local_ip4, pg_interface.name))
 162         arp_req = self.create_arp_req()
 163         pg_interface.add_stream(arp_req)
 164         pg_interface.enable_capture()
 165         self.test.pg_start()
 166         info(self.test.vapi.cli("show trace"))
 167         arp_reply = pg_interface.get_capture()
 168         if arp_reply is None or len(arp_reply) == 0:
 169             info("No ARP received on port %s" % pg_interface.name)
 170             return
 171         arp_reply = arp_reply[0]
 172         # Make Dot1AD packet content recognizable to scapy
 173         if arp_reply.type == 0x88a8:
 174             arp_reply.type = 0x8100
 175             arp_reply = Ether(str(arp_reply))
 176         try:
 177             if arp_reply[ARP].op == ARP.is_at:
 178                 info("VPP %s MAC address is %s " %
 179                      (self.name, arp_reply[ARP].hwsrc))
 180                 self._local_mac = arp_reply[ARP].hwsrc
 181             else:
 182                 info("No ARP received on port %s" % pg_interface.name)
 183         except:
 184             error("Unexpected response to ARP request:")
 185             error(arp_reply.show())
 186             raise
 187
 188     def resolve_ndp(self, pg_interface=None):
 189         """Resolve NDP using provided packet-generator interface
 190
 191         :param pg_interface: interface used to resolve, if None then this
 192             interface is used
 193
 194         """
 195         if pg_interface is None:
 196             pg_interface = self
 197         info("Sending NDP request for %s on port %s" %
 198              (self.local_ip6, pg_interface.name))
 199         ndp_req = self.create_ndp_req()
 200         pg_interface.add_stream(ndp_req)
 201         pg_interface.enable_capture()
 202         self.test.pg_start()
 203         info(self.test.vapi.cli("show trace"))
 204         ndp_reply = pg_interface.get_capture()
 205         if ndp_reply is None or len(ndp_reply) == 0:
 206             info("No NDP received on port %s" % pg_interface.name)
 207             return
 208         ndp_reply = ndp_reply[0]
 209         # Make Dot1AD packet content recognizable to scapy
 210         if ndp_reply.type == 0x88a8:
 211             ndp_reply.type = 0x8100
 212             ndp_reply = Ether(str(ndp_reply))
 213         try:
 214             ndp_na = ndp_reply[ICMPv6ND_NA]
 215             opt = ndp_na[ICMPv6NDOptDstLLAddr]
 216             info("VPP %s MAC address is %s " %
 217                  (self.name, opt.lladdr))
 218             self._local_mac = opt.lladdr
 219         except:
 220             error("Unexpected response to NDP request:")
 221             error(ndp_reply.show())
 222             raise