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