API refactoring : bfd
[vpp.git] / test / vpp_pg_interface.py
index 533c460..634d7d3 100644 (file)
@@ -1,12 +1,24 @@
 import os
 import time
-from scapy.utils import wrpcap, rdpcap
+from scapy.utils import wrpcap, rdpcap, PcapReader
 from vpp_interface import VppInterface
 
 from scapy.layers.l2 import Ether, ARP
-from scapy.layers.inet6 import IPv6, ICMPv6ND_NS, ICMPv6ND_NA, \
-    ICMPv6NDOptSrcLLAddr, ICMPv6NDOptDstLLAddr
-from util import ppp
+from scapy.layers.inet6 import IPv6, ICMPv6ND_NS, ICMPv6ND_NA,\
+    ICMPv6NDOptSrcLLAddr, ICMPv6NDOptDstLLAddr, ICMPv6ND_RA, RouterAlert, \
+    IPv6ExtHdrHopByHop
+from util import ppp, ppc
+
+
+def is_ipv6_misc(p):
+    """ Is packet one of uninteresting IPv6 broadcasts? """
+    if p.haslayer(ICMPv6ND_RA):
+        return True
+    if p.haslayer(IPv6ExtHdrHopByHop):
+        for o in p[IPv6ExtHdrHopByHop].options:
+            if isinstance(o, RouterAlert):
+                return True
+    return False
 
 
 class VppPGInterface(VppInterface):
@@ -93,6 +105,7 @@ class VppPGInterface(VppInterface):
             pass
         # FIXME this should be an API, but no such exists atm
         self.test.vapi.cli(self.capture_cli)
+        self._pcap_reader = None
 
     def add_stream(self, pkts):
         """
@@ -113,25 +126,108 @@ class VppPGInterface(VppInterface):
         except:
             pass
         wrpcap(self.in_path, pkts)
+        self.test.register_capture(self.cap_name)
         # FIXME this should be an API, but no such exists atm
         self.test.vapi.cli(self.input_cli)
-        self.test.pg_streams.append(self.cap_name)
-        self.test.vapi.cli("trace add pg-input %d" % len(pkts))
 
-    def get_capture(self):
+    def get_capture(self, remark=None, filter_fn=is_ipv6_misc):
         """
         Get captured packets
 
+        :param remark: remark printed into debug logs
+        :param filter_fn: filter applied to each packet, packets for which
+                          the filter returns True are removed from capture
         :returns: iterable packets
         """
         try:
+            self.wait_for_capture_file()
             output = rdpcap(self.out_path)
+            self.test.logger.debug("Capture has %s packets" % len(output.res))
         except IOError:  # TODO
-            self.test.logger.error("File %s does not exist, probably because no"
+            self.test.logger.debug("File %s does not exist, probably because no"
                                    " packets arrived" % self.out_path)
-            return []
+            if remark:
+                raise Exception("No packets captured on %s(%s)" %
+                                (self.name, remark))
+            else:
+                raise Exception("No packets captured on %s" % self.name)
+        before = len(output.res)
+        if filter_fn:
+            output.res = [p for p in output.res if not filter_fn(p)]
+        removed = len(output.res) - before
+        if removed:
+            self.test.logger.debug(
+                "Filtered out %s packets from capture (returning %s)" %
+                (removed, len(output.res)))
         return output
 
+    def assert_nothing_captured(self, remark=None):
+        if os.path.isfile(self.out_path):
+            try:
+                capture = self.get_capture(remark=remark)
+                self.test.logger.error(
+                    ppc("Unexpected packets captured:", capture))
+            except:
+                pass
+            if remark:
+                raise AssertionError(
+                    "Capture file present for interface %s(%s)" %
+                    (self.name, remark))
+            else:
+                raise AssertionError("Capture file present for interface %s" %
+                                     self.name)
+
+    def wait_for_capture_file(self, timeout=1):
+        """
+        Wait until pcap capture file appears
+
+        :param timeout: How long to wait for the packet (default 1s)
+
+        :raises Exception: if the capture file does not appear within timeout
+        """
+        limit = time.time() + timeout
+        if not os.path.isfile(self.out_path):
+            self.test.logger.debug(
+                "Waiting for capture file to appear, timeout is %ss", timeout)
+        else:
+            self.test.logger.debug("Capture file already exists")
+            return
+        while time.time() < limit:
+            if os.path.isfile(self.out_path):
+                break
+            time.sleep(0)  # yield
+        if os.path.isfile(self.out_path):
+            self.test.logger.debug("Capture file appeared after %fs" %
+                                   (time.time() - (limit - timeout)))
+        else:
+            self.test.logger.debug("Timeout - capture file still nowhere")
+            raise Exception("Capture file did not appear within timeout")
+
+    def wait_for_packet(self, timeout):
+        """
+        Wait for next packet captured with a timeout
+
+        :param timeout: How long to wait for the packet
+
+        :returns: Captured packet if no packet arrived within timeout
+        :raises Exception: if no packet arrives within timeout
+        """
+        limit = time.time() + timeout
+        if self._pcap_reader is None:
+            self.wait_for_capture_file(timeout)
+            self._pcap_reader = PcapReader(self.out_path)
+
+        self.test.logger.debug("Waiting for packet")
+        while time.time() < limit:
+            p = self._pcap_reader.recv()
+            if p is not None:
+                self.test.logger.debug("Packet received after %fs",
+                                       (time.time() - (limit - timeout)))
+                return p
+            time.sleep(0)  # yield
+        self.test.logger.debug("Timeout - no packets received")
+        raise Exception("Packet didn't arrive within timeout")
+
     def create_arp_req(self):
         """Create ARP request applicable for this interface"""
         return (Ether(dst="ff:ff:ff:ff:ff:ff", src=self.remote_mac) /
@@ -161,11 +257,11 @@ class VppPGInterface(VppInterface):
         pg_interface.enable_capture()
         self.test.pg_start()
         self.test.logger.info(self.test.vapi.cli("show trace"))
-        arp_reply = pg_interface.get_capture()
-        if arp_reply is None or len(arp_reply) == 0:
-            self.test.logger.info(
-                "No ARP received on port %s" %
-                pg_interface.name)
+        try:
+            arp_reply = pg_interface.get_capture(filter_fn=None)
+        except:
+            self.test.logger.info("No ARP received on port %s" %
+                                  pg_interface.name)
             return
         arp_reply = arp_reply[0]
         # Make Dot1AD packet content recognizable to scapy
@@ -202,24 +298,29 @@ class VppPGInterface(VppInterface):
         pg_interface.enable_capture()
         self.test.pg_start()
         self.test.logger.info(self.test.vapi.cli("show trace"))
-        ndp_reply = pg_interface.get_capture()
-        if ndp_reply is None or len(ndp_reply) == 0:
+        replies = pg_interface.get_capture(filter_fn=None)
+        if replies is None or len(replies) == 0:
             self.test.logger.info(
                 "No NDP received on port %s" %
                 pg_interface.name)
             return
-        ndp_reply = ndp_reply[0]
-        # Make Dot1AD packet content recognizable to scapy
-        if ndp_reply.type == 0x88a8:
-            ndp_reply.type = 0x8100
-            ndp_reply = Ether(str(ndp_reply))
-        try:
-            ndp_na = ndp_reply[ICMPv6ND_NA]
-            opt = ndp_na[ICMPv6NDOptDstLLAddr]
-            self.test.logger.info("VPP %s MAC address is %s " %
-                                  (self.name, opt.lladdr))
-            self._local_mac = opt.lladdr
-        except:
-            self.test.logger.error(
-                ppp("Unexpected response to NDP request:", ndp_reply))
+        # Enabling IPv6 on an interface can generate more than the
+        # ND reply we are looking for (namely MLD). So loop through
+        # the replies to look for want we want.
+        for ndp_reply in replies:
+            # Make Dot1AD packet content recognizable to scapy
+            if ndp_reply.type == 0x88a8:
+                ndp_reply.type = 0x8100
+                ndp_reply = Ether(str(ndp_reply))
+            try:
+                ndp_na = ndp_reply[ICMPv6ND_NA]
+                opt = ndp_na[ICMPv6NDOptDstLLAddr]
+                self.test.logger.info("VPP %s MAC address is %s " %
+                                      (self.name, opt.lladdr))
+                self._local_mac = opt.lladdr
+            except:
+                self.test.logger.info(
+                    ppp("Unexpected response to NDP request:", ndp_reply))
+        # if no packets above provided the local MAC, then this failed.
+        if not hasattr(self, '_local_mac'):
             raise