Merge "forwarding_test: Add a test for forwarding UDPv6"android-o-mr1-preview-2android-o-mr1-preview-1

2 files changed, 75 insertions, 20 deletions

diff --git a/net/test/forwarding_test.py b/net/test/forwarding_test.py
index cf00af1..34394cd 100755
--- a/net/test/forwarding_test.py
+++ b/net/test/forwarding_test.py
@@ -24,21 +24,7 @@ import multinetwork_base
 import net_test
 import packets
 
-
 class ForwardingTest(multinetwork_base.MultiNetworkBaseTest):
-  """Checks that IPv6 forwarding doesn't crash the system.
-
-  Relevant kernel commits:
-    upstream net-next:
-      e7eadb4 ipv6: inet6_sk() should use sk_fullsock()
-    android-3.10:
-      feee3c1 ipv6: inet6_sk() should use sk_fullsock()
-      cdab04e net: add sk_fullsock() helper
-    android-3.18:
-      8246f18 ipv6: inet6_sk() should use sk_fullsock()
-      bea19db net: add sk_fullsock() helper
-  """
-
   TCP_TIME_WAIT = 6
 
   def ForwardBetweenInterfaces(self, enabled, iface1, iface2):
@@ -52,7 +38,63 @@ class ForwardingTest(multinetwork_base.MultiNetworkBaseTest):
   def tearDown(self):
     self.SetSysctl("/proc/sys/net/ipv6/conf/all/forwarding", 0)
 
-  def CheckForwardingCrash(self, netid, iface1, iface2):
+  """Checks that IPv6 forwarding works for UDP packets and is not broken by early demux.
+
+  Relevant kernel commits:
+    upstream:
+      5425077d73e0c8e net: ipv6: Add early demux handler for UDP unicast
+      0bd84065b19bca1 net: ipv6: Fix UDP early demux lookup with udp_l3mdev_accept=0
+      Ifa9c2ddfaa5b51 net: ipv6: reset daddr and dport in sk if connect() fails
+  """
+  def CheckForwardingUdp(self, netid, iface1, iface2):
+    # TODO: Make a test for IPv4
+    # 1. Make version as an argument. Pick address to bind from array based
+    #    on version.
+    # 2. The prefix length of the address is hardcoded to /64. Use the subnet
+    #    mask there instead.
+    # 3. We recreate the address with SendRA, which obviously only works for
+    #    IPv6. Use AddAddress for IPv4.
+
+    # Create a UDP socket and bind to it
+    version = 6
+    s = net_test.UDPSocket(AF_INET6)
+    self.SetSocketMark(s, netid)
+    s.setsockopt(SOL_SOCKET, SO_REUSEADDR, 1)
+    s.bind(("::", 53))
+
+    remoteaddr = self.GetRemoteAddress(version)
+    myaddr = self.MyAddress(version, netid)
+
+    try:
+      # Delete address and check if packet is forwarded
+      # (and not dropped because an incorrect socket match happened)
+      self.iproute.DelAddress(myaddr, 64, self.ifindices[netid])
+      hoplimit = 39
+      desc, udp_pkt = packets.UDPWithOptions(version, myaddr, remoteaddr, 53)
+      # Decrements the hoplimit of a packet to simulate forwarding.
+      desc_fwded, udp_fwd = packets.UDPWithOptions(version, myaddr, remoteaddr,
+                                                   53, hoplimit - 1)
+      msg = "Sent %s, expected %s" % (desc, desc_fwded)
+      self.ReceivePacketOn(iface1, udp_pkt)
+      self.ExpectPacketOn(iface2, msg, udp_fwd)
+    finally:
+      # Recreate the address.
+      self.SendRA(netid)
+      s.close()
+
+  """Checks that IPv6 forwarding doesn't crash the system.
+
+  Relevant kernel commits:
+    upstream net-next:
+      e7eadb4 ipv6: inet6_sk() should use sk_fullsock()
+    android-3.10:
+      feee3c1 ipv6: inet6_sk() should use sk_fullsock()
+      cdab04e net: add sk_fullsock() helper
+    android-3.18:
+      8246f18 ipv6: inet6_sk() should use sk_fullsock()
+      bea19db net: add sk_fullsock() helper
+  """
+  def CheckForwardingCrashTcp(self, netid, iface1, iface2):
     version = 6
     listensocket = net_test.IPv6TCPSocket()
     self.SetSocketMark(listensocket, netid)
@@ -101,17 +143,30 @@ class ForwardingTest(multinetwork_base.MultiNetworkBaseTest):
       self.SendRA(netid)
       listensocket.close()
 
-  def testCrash(self):
+  def CheckForwardingHandlerByProto(self, protocol, netid, iif, oif):
+    if protocol == IPPROTO_UDP:
+      self.CheckForwardingUdp(netid, iif, oif)
+    elif protocol == IPPROTO_TCP:
+      self.CheckForwardingCrashTcp(netid, iif, oif)
+    else:
+      raise NotImplementedError
+
+  def CheckForwardingByProto(self, proto):
     # Run the test a few times as it doesn't crash/hang the first time.
     for netids in itertools.permutations(self.tuns):
       # Pick an interface to send traffic on and two to forward traffic between.
       netid, iface1, iface2 = random.sample(netids, 3)
       self.ForwardBetweenInterfaces(True, iface1, iface2)
       try:
-        self.CheckForwardingCrash(netid, iface1, iface2)
+        self.CheckForwardingHandlerByProto(proto, netid, iface1, iface2)
       finally:
         self.ForwardBetweenInterfaces(False, iface1, iface2)
 
+  def testForwardingUdp(self):
+    self.CheckForwardingByProto(IPPROTO_UDP)
+
+  def testForwardingCrashTcp(self):
+    self.CheckForwardingByProto(IPPROTO_TCP)
 
 if __name__ == "__main__":
   unittest.main()
diff --git a/net/test/packets.py b/net/test/packets.py
index c36efe8..7ad77bb 100644
--- a/net/test/packets.py
+++ b/net/test/packets.py
@@ -61,14 +61,14 @@ def UDP(version, srcaddr, dstaddr, sport=0):
           ip(src=srcaddr, dst=dstaddr) /
           scapy.UDP(sport=sport, dport=53) / UDP_PAYLOAD)
 
-def UDPWithOptions(version, srcaddr, dstaddr, sport=0):
+def UDPWithOptions(version, srcaddr, dstaddr, sport=0, lifetime=39):
   if version == 4:
-    packet = (scapy.IP(src=srcaddr, dst=dstaddr, ttl=39, tos=0x83) /
+    packet = (scapy.IP(src=srcaddr, dst=dstaddr, ttl=lifetime, tos=0x83) /
               scapy.UDP(sport=sport, dport=53) /
               UDP_PAYLOAD)
   else:
     packet = (scapy.IPv6(src=srcaddr, dst=dstaddr,
-                         fl=0xbeef, hlim=39, tc=0x83) /
+                         fl=0xbeef, hlim=lifetime, tc=0x83) /
               scapy.UDP(sport=sport, dport=53) /
               UDP_PAYLOAD)
   return ("UDPv%d packet with options" % version, packet)