diff options
| -rw-r--r-- | pkg/tcpip/network/ipv4/ipv4_test.go | 3 | ||||
| -rw-r--r-- | pkg/tcpip/stack/nic.go | 27 | ||||
| -rw-r--r-- | pkg/tcpip/stack/route.go | 13 | ||||
| -rw-r--r-- | pkg/tcpip/stack/stack.go | 2 | ||||
| -rw-r--r-- | pkg/tcpip/stack/stack_test.go | 123 | ||||
| -rw-r--r-- | pkg/tcpip/stack/transport_demuxer.go | 47 | ||||
| -rw-r--r-- | pkg/tcpip/tcpip.go | 44 | ||||
| -rw-r--r-- | pkg/tcpip/tcpip_test.go | 31 | ||||
| -rw-r--r-- | pkg/tcpip/transport/udp/udp_test.go | 78 | ||||
| -rw-r--r-- | test/syscalls/linux/socket_ipv4_udp_unbound_external_networking.cc | 408 |
10 files changed, 636 insertions, 140 deletions
diff --git a/pkg/tcpip/network/ipv4/ipv4_test.go b/pkg/tcpip/network/ipv4/ipv4_test.go index b6641ccc3..a53894c01 100644 --- a/pkg/tcpip/network/ipv4/ipv4_test.go +++ b/pkg/tcpip/network/ipv4/ipv4_test.go @@ -47,9 +47,6 @@ func TestExcludeBroadcast(t *testing.T) { t.Fatalf("CreateNIC failed: %v", err) } - if err := s.AddAddress(1, ipv4.ProtocolNumber, header.IPv4Broadcast); err != nil { - t.Fatalf("AddAddress failed: %v", err) - } if err := s.AddAddress(1, ipv4.ProtocolNumber, header.IPv4Any); err != nil { t.Fatalf("AddAddress failed: %v", err) } diff --git a/pkg/tcpip/stack/nic.go b/pkg/tcpip/stack/nic.go index f6106f762..5993fe582 100644 --- a/pkg/tcpip/stack/nic.go +++ b/pkg/tcpip/stack/nic.go @@ -104,6 +104,16 @@ func newNIC(stack *Stack, id tcpip.NICID, name string, ep LinkEndpoint, loopback func (n *NIC) enable() *tcpip.Error { n.attachLinkEndpoint() + // Create an endpoint to receive broadcast packets on this interface. + if _, ok := n.stack.networkProtocols[header.IPv4ProtocolNumber]; ok { + if err := n.AddAddress(tcpip.ProtocolAddress{ + Protocol: header.IPv4ProtocolNumber, + AddressWithPrefix: tcpip.AddressWithPrefix{header.IPv4Broadcast, 8 * header.IPv4AddressSize}, + }, NeverPrimaryEndpoint); err != nil { + return err + } + } + // Join the IPv6 All-Nodes Multicast group if the stack is configured to // use IPv6. This is required to ensure that this node properly receives // and responds to the various NDP messages that are destined to the @@ -372,7 +382,7 @@ func (n *NIC) AllAddresses() []tcpip.ProtocolAddress { addrs := make([]tcpip.ProtocolAddress, 0, len(n.endpoints)) for nid, ref := range n.endpoints { - // Don't include expired or tempory endpoints to avoid confusion and + // Don't include expired or temporary endpoints to avoid confusion and // prevent the caller from using those. switch ref.getKind() { case permanentExpired, temporary: @@ -624,21 +634,6 @@ func (n *NIC) DeliverNetworkPacket(linkEP LinkEndpoint, remote, _ tcpip.LinkAddr n.stack.AddLinkAddress(n.id, src, remote) - // If the packet is destined to the IPv4 Broadcast address, then make a - // route to each IPv4 network endpoint and let each endpoint handle the - // packet. - if dst == header.IPv4Broadcast { - // n.endpoints is mutex protected so acquire lock. - n.mu.RLock() - for _, ref := range n.endpoints { - if ref.isValidForIncoming() && ref.protocol == header.IPv4ProtocolNumber && ref.tryIncRef() { - handlePacket(protocol, dst, src, linkEP.LinkAddress(), remote, ref, vv) - } - } - n.mu.RUnlock() - return - } - if ref := n.getRef(protocol, dst); ref != nil { handlePacket(protocol, dst, src, linkEP.LinkAddress(), remote, ref, vv) return diff --git a/pkg/tcpip/stack/route.go b/pkg/tcpip/stack/route.go index 5c8b7977a..0b09e6517 100644 --- a/pkg/tcpip/stack/route.go +++ b/pkg/tcpip/stack/route.go @@ -59,6 +59,8 @@ func makeRoute(netProto tcpip.NetworkProtocolNumber, localAddr, remoteAddr tcpip loop = PacketLoop } else if multicastLoop && (header.IsV4MulticastAddress(remoteAddr) || header.IsV6MulticastAddress(remoteAddr)) { loop |= PacketLoop + } else if remoteAddr == header.IPv4Broadcast { + loop |= PacketLoop } return Route{ @@ -208,10 +210,17 @@ func (r *Route) Clone() Route { return *r } -// MakeLoopedRoute duplicates the given route and tweaks it in case of multicast. +// MakeLoopedRoute duplicates the given route with special handling for routes +// used for sending multicast or broadcast packets. In those cases the +// multicast/broadcast address is the remote address when sending out, but for +// incoming (looped) packets it becomes the local address. Similarly, the local +// interface address that was the local address going out becomes the remote +// address coming in. This is different to unicast routes where local and +// remote addresses remain the same as they identify location (local vs remote) +// not direction (source vs destination). func (r *Route) MakeLoopedRoute() Route { l := r.Clone() - if header.IsV4MulticastAddress(r.RemoteAddress) || header.IsV6MulticastAddress(r.RemoteAddress) { + if r.RemoteAddress == header.IPv4Broadcast || header.IsV4MulticastAddress(r.RemoteAddress) || header.IsV6MulticastAddress(r.RemoteAddress) { l.RemoteAddress, l.LocalAddress = l.LocalAddress, l.RemoteAddress l.RemoteLinkAddress = l.LocalLinkAddress } diff --git a/pkg/tcpip/stack/stack.go b/pkg/tcpip/stack/stack.go index 90c2cf1be..ff574a055 100644 --- a/pkg/tcpip/stack/stack.go +++ b/pkg/tcpip/stack/stack.go @@ -902,7 +902,7 @@ func (s *Stack) FindRoute(id tcpip.NICID, localAddr, remoteAddr tcpip.Address, n } } else { for _, route := range s.routeTable { - if (id != 0 && id != route.NIC) || (len(remoteAddr) != 0 && !isBroadcast && !route.Destination.Contains(remoteAddr)) { + if (id != 0 && id != route.NIC) || (len(remoteAddr) != 0 && !route.Destination.Contains(remoteAddr)) { continue } if nic, ok := s.nics[route.NIC]; ok { diff --git a/pkg/tcpip/stack/stack_test.go b/pkg/tcpip/stack/stack_test.go index d2dede8a9..a2e0a6e7b 100644 --- a/pkg/tcpip/stack/stack_test.go +++ b/pkg/tcpip/stack/stack_test.go @@ -952,10 +952,10 @@ func TestSpoofingWithAddress(t *testing.T) { t.Fatal("FindRoute failed:", err) } if r.LocalAddress != nonExistentLocalAddr { - t.Errorf("Route has wrong local address: got %s, want %s", r.LocalAddress, nonExistentLocalAddr) + t.Errorf("got Route.LocalAddress = %s, want = %s", r.LocalAddress, nonExistentLocalAddr) } if r.RemoteAddress != dstAddr { - t.Errorf("Route has wrong remote address: got %s, want %s", r.RemoteAddress, dstAddr) + t.Errorf("got Route.RemoteAddress = %s, want = %s", r.RemoteAddress, dstAddr) } // Sending a packet works. testSendTo(t, s, dstAddr, ep, nil) @@ -967,10 +967,10 @@ func TestSpoofingWithAddress(t *testing.T) { t.Fatal("FindRoute failed:", err) } if r.LocalAddress != localAddr { - t.Errorf("Route has wrong local address: got %s, want %s", r.LocalAddress, nonExistentLocalAddr) + t.Errorf("got Route.LocalAddress = %s, want = %s", r.LocalAddress, nonExistentLocalAddr) } if r.RemoteAddress != dstAddr { - t.Errorf("Route has wrong remote address: got %s, want %s", r.RemoteAddress, dstAddr) + t.Errorf("got Route.RemoteAddress = %s, want = %s", r.RemoteAddress, dstAddr) } // Sending a packet using the route works. testSend(t, r, ep, nil) @@ -1016,17 +1016,33 @@ func TestSpoofingNoAddress(t *testing.T) { t.Fatal("FindRoute failed:", err) } if r.LocalAddress != nonExistentLocalAddr { - t.Errorf("Route has wrong local address: got %s, want %s", r.LocalAddress, nonExistentLocalAddr) + t.Errorf("got Route.LocalAddress = %s, want = %s", r.LocalAddress, nonExistentLocalAddr) } if r.RemoteAddress != dstAddr { - t.Errorf("Route has wrong remote address: got %s, want %s", r.RemoteAddress, dstAddr) + t.Errorf("got Route.RemoteAddress = %s, want = %s", r.RemoteAddress, dstAddr) } // Sending a packet works. // FIXME(b/139841518):Spoofing doesn't work if there is no primary address. // testSendTo(t, s, remoteAddr, ep, nil) } -func TestBroadcastNeedsNoRoute(t *testing.T) { +func verifyRoute(gotRoute, wantRoute stack.Route) error { + if gotRoute.LocalAddress != wantRoute.LocalAddress { + return fmt.Errorf("bad local address: got %s, want = %s", gotRoute.LocalAddress, wantRoute.LocalAddress) + } + if gotRoute.RemoteAddress != wantRoute.RemoteAddress { + return fmt.Errorf("bad remote address: got %s, want = %s", gotRoute.RemoteAddress, wantRoute.RemoteAddress) + } + if gotRoute.RemoteLinkAddress != wantRoute.RemoteLinkAddress { + return fmt.Errorf("bad remote link address: got %s, want = %s", gotRoute.RemoteLinkAddress, wantRoute.RemoteLinkAddress) + } + if gotRoute.NextHop != wantRoute.NextHop { + return fmt.Errorf("bad next-hop address: got %s, want = %s", gotRoute.NextHop, wantRoute.NextHop) + } + return nil +} + +func TestOutgoingBroadcastWithEmptyRouteTable(t *testing.T) { s := stack.New(stack.Options{ NetworkProtocols: []stack.NetworkProtocol{fakeNetFactory()}, }) @@ -1039,28 +1055,99 @@ func TestBroadcastNeedsNoRoute(t *testing.T) { // If there is no endpoint, it won't work. if _, err := s.FindRoute(1, header.IPv4Any, header.IPv4Broadcast, fakeNetNumber, false /* multicastLoop */); err != tcpip.ErrNetworkUnreachable { - t.Fatalf("got FindRoute(1, %v, %v, %v) = %v, want = %s", header.IPv4Any, header.IPv4Broadcast, fakeNetNumber, err, tcpip.ErrNetworkUnreachable) + t.Fatalf("got FindRoute(1, %s, %s, %d) = %s, want = %s", header.IPv4Any, header.IPv4Broadcast, fakeNetNumber, err, tcpip.ErrNetworkUnreachable) } - if err := s.AddAddress(1, fakeNetNumber, header.IPv4Any); err != nil { - t.Fatalf("AddAddress(%v, %v) failed: %s", fakeNetNumber, header.IPv4Any, err) + protoAddr := tcpip.ProtocolAddress{Protocol: fakeNetNumber, AddressWithPrefix: tcpip.AddressWithPrefix{header.IPv4Any, 0}} + if err := s.AddProtocolAddress(1, protoAddr); err != nil { + t.Fatalf("AddProtocolAddress(1, %s) failed: %s", protoAddr, err) } r, err := s.FindRoute(1, header.IPv4Any, header.IPv4Broadcast, fakeNetNumber, false /* multicastLoop */) if err != nil { - t.Fatalf("FindRoute(1, %v, %v, %v) failed: %v", header.IPv4Any, header.IPv4Broadcast, fakeNetNumber, err) + t.Fatalf("FindRoute(1, %s, %s, %d) failed: %s", header.IPv4Any, header.IPv4Broadcast, fakeNetNumber, err) + } + if err := verifyRoute(r, stack.Route{LocalAddress: header.IPv4Any, RemoteAddress: header.IPv4Broadcast}); err != nil { + t.Errorf("FindRoute(1, %s, %s, %d) returned unexpected Route: %s)", header.IPv4Any, header.IPv4Broadcast, fakeNetNumber, err) } - if r.LocalAddress != header.IPv4Any { - t.Errorf("Bad local address: got %v, want = %v", r.LocalAddress, header.IPv4Any) + // If the NIC doesn't exist, it won't work. + if _, err := s.FindRoute(2, header.IPv4Any, header.IPv4Broadcast, fakeNetNumber, false /* multicastLoop */); err != tcpip.ErrNetworkUnreachable { + t.Fatalf("got FindRoute(2, %s, %s, %d) = %s want = %s", header.IPv4Any, header.IPv4Broadcast, fakeNetNumber, err, tcpip.ErrNetworkUnreachable) } +} + +func TestOutgoingBroadcastWithRouteTable(t *testing.T) { + defaultAddr := tcpip.AddressWithPrefix{header.IPv4Any, 0} + // Local subnet on NIC1: 192.168.1.58/24, gateway 192.168.1.1. + nic1Addr := tcpip.AddressWithPrefix{"\xc0\xa8\x01\x3a", 24} + nic1Gateway := tcpip.Address("\xc0\xa8\x01\x01") + // Local subnet on NIC2: 10.10.10.5/24, gateway 10.10.10.1. + nic2Addr := tcpip.AddressWithPrefix{"\x0a\x0a\x0a\x05", 24} + nic2Gateway := tcpip.Address("\x0a\x0a\x0a\x01") - if r.RemoteAddress != header.IPv4Broadcast { - t.Errorf("Bad remote address: got %v, want = %v", r.RemoteAddress, header.IPv4Broadcast) + // Create a new stack with two NICs. + s := stack.New(stack.Options{ + NetworkProtocols: []stack.NetworkProtocol{fakeNetFactory()}, + }) + ep := channel.New(10, defaultMTU, "") + if err := s.CreateNIC(1, ep); err != nil { + t.Fatalf("CreateNIC failed: %s", err) + } + if err := s.CreateNIC(2, ep); err != nil { + t.Fatalf("CreateNIC failed: %s", err) + } + nic1ProtoAddr := tcpip.ProtocolAddress{fakeNetNumber, nic1Addr} + if err := s.AddProtocolAddress(1, nic1ProtoAddr); err != nil { + t.Fatalf("AddProtocolAddress(1, %s) failed: %s", nic1ProtoAddr, err) } - // If the NIC doesn't exist, it won't work. - if _, err := s.FindRoute(2, header.IPv4Any, header.IPv4Broadcast, fakeNetNumber, false /* multicastLoop */); err != tcpip.ErrNetworkUnreachable { - t.Fatalf("got FindRoute(2, %v, %v, %v) = %v want = %v", header.IPv4Any, header.IPv4Broadcast, fakeNetNumber, err, tcpip.ErrNetworkUnreachable) + nic2ProtoAddr := tcpip.ProtocolAddress{fakeNetNumber, nic2Addr} + if err := s.AddProtocolAddress(2, nic2ProtoAddr); err != nil { + t.Fatalf("AddAddress(2, %s) failed: %s", nic2ProtoAddr, err) + } + + // Set the initial route table. + rt := []tcpip.Route{ + {Destination: nic1Addr.Subnet(), NIC: 1}, + {Destination: nic2Addr.Subnet(), NIC: 2}, + {Destination: defaultAddr.Subnet(), Gateway: nic2Gateway, NIC: 2}, + {Destination: defaultAddr.Subnet(), Gateway: nic1Gateway, NIC: 1}, + } + s.SetRouteTable(rt) + + // When an interface is given, the route for a broadcast goes through it. + r, err := s.FindRoute(1, nic1Addr.Address, header.IPv4Broadcast, fakeNetNumber, false /* multicastLoop */) + if err != nil { + t.Fatalf("FindRoute(1, %s, %s, %d) failed: %s", nic1Addr.Address, header.IPv4Broadcast, fakeNetNumber, err) + } + if err := verifyRoute(r, stack.Route{LocalAddress: nic1Addr.Address, RemoteAddress: header.IPv4Broadcast}); err != nil { + t.Errorf("FindRoute(1, %s, %s, %d) returned unexpected Route: %s)", nic1Addr.Address, header.IPv4Broadcast, fakeNetNumber, err) + } + + // When an interface is not given, it consults the route table. + // 1. Case: Using the default route. + r, err = s.FindRoute(0, "", header.IPv4Broadcast, fakeNetNumber, false /* multicastLoop */) + if err != nil { + t.Fatalf("FindRoute(0, \"\", %s, %d) failed: %s", header.IPv4Broadcast, fakeNetNumber, err) + } + if err := verifyRoute(r, stack.Route{LocalAddress: nic2Addr.Address, RemoteAddress: header.IPv4Broadcast}); err != nil { + t.Errorf("FindRoute(0, \"\", %s, %d) returned unexpected Route: %s)", header.IPv4Broadcast, fakeNetNumber, err) + } + + // 2. Case: Having an explicit route for broadcast will select that one. + rt = append( + []tcpip.Route{ + {Destination: tcpip.AddressWithPrefix{header.IPv4Broadcast, 8 * header.IPv4AddressSize}.Subnet(), NIC: 1}, + }, + rt..., + ) + s.SetRouteTable(rt) + r, err = s.FindRoute(0, "", header.IPv4Broadcast, fakeNetNumber, false /* multicastLoop */) + if err != nil { + t.Fatalf("FindRoute(0, \"\", %s, %d) failed: %s", header.IPv4Broadcast, fakeNetNumber, err) + } + if err := verifyRoute(r, stack.Route{LocalAddress: nic1Addr.Address, RemoteAddress: header.IPv4Broadcast}); err != nil { + t.Errorf("FindRoute(0, \"\", %s, %d) returned unexpected Route: %s)", header.IPv4Broadcast, fakeNetNumber, err) } } diff --git a/pkg/tcpip/stack/transport_demuxer.go b/pkg/tcpip/stack/transport_demuxer.go index 8c768c299..92267ce4d 100644 --- a/pkg/tcpip/stack/transport_demuxer.go +++ b/pkg/tcpip/stack/transport_demuxer.go @@ -63,7 +63,7 @@ func (epsByNic *endpointsByNic) handlePacket(r *Route, id TransportEndpointID, v // If this is a broadcast or multicast datagram, deliver the datagram to all // endpoints bound to the right device. - if id.LocalAddress == header.IPv4Broadcast || header.IsV4MulticastAddress(id.LocalAddress) || header.IsV6MulticastAddress(id.LocalAddress) { + if isMulticastOrBroadcast(id.LocalAddress) { mpep.handlePacketAll(r, id, vv) epsByNic.mu.RUnlock() // Don't use defer for performance reasons. return @@ -338,23 +338,14 @@ func (d *transportDemuxer) deliverPacket(r *Route, protocol tcpip.TransportProto return false } - // If a sender bound to the Loopback interface sends a broadcast, - // that broadcast must not be delivered to the sender. - if loopbackSubnet.Contains(r.RemoteAddress) && r.LocalAddress == header.IPv4Broadcast && id.LocalPort == id.RemotePort { - return false - } - - // If the packet is a broadcast, then find all matching transport endpoints. - // Otherwise, try to find a single matching transport endpoint. - destEps := make([]*endpointsByNic, 0, 1) eps.mu.RLock() - if protocol == header.UDPProtocolNumber && id.LocalAddress == header.IPv4Broadcast { - for epID, endpoint := range eps.endpoints { - if epID.LocalPort == id.LocalPort { - destEps = append(destEps, endpoint) - } - } + // Determine which transport endpoint or endpoints to deliver this packet to. + // If the packet is a broadcast or multicast, then find all matching + // transport endpoints. + var destEps []*endpointsByNic + if protocol == header.UDPProtocolNumber && isMulticastOrBroadcast(id.LocalAddress) { + destEps = d.findAllEndpointsLocked(eps, vv, id) } else if ep := d.findEndpointLocked(eps, vv, id); ep != nil { destEps = append(destEps, ep) } @@ -426,10 +417,11 @@ func (d *transportDemuxer) deliverControlPacket(n *NIC, net tcpip.NetworkProtoco return true } -func (d *transportDemuxer) findEndpointLocked(eps *transportEndpoints, vv buffer.VectorisedView, id TransportEndpointID) *endpointsByNic { +func (d *transportDemuxer) findAllEndpointsLocked(eps *transportEndpoints, vv buffer.VectorisedView, id TransportEndpointID) []*endpointsByNic { + var matchedEPs []*endpointsByNic // Try to find a match with the id as provided. if ep, ok := eps.endpoints[id]; ok { - return ep + matchedEPs = append(matchedEPs, ep) } // Try to find a match with the id minus the local address. @@ -437,7 +429,7 @@ func (d *transportDemuxer) findEndpointLocked(eps *transportEndpoints, vv buffer nid.LocalAddress = "" if ep, ok := eps.endpoints[nid]; ok { - return ep + matchedEPs = append(matchedEPs, ep) } // Try to find a match with the id minus the remote part. @@ -445,15 +437,24 @@ func (d *transportDemuxer) findEndpointLocked(eps *transportEndpoints, vv buffer nid.RemoteAddress = "" nid.RemotePort = 0 if ep, ok := eps.endpoints[nid]; ok { - return ep + matchedEPs = append(matchedEPs, ep) } // Try to find a match with only the local port. nid.LocalAddress = "" if ep, ok := eps.endpoints[nid]; ok { - return ep + matchedEPs = append(matchedEPs, ep) } + return matchedEPs +} + +// findEndpointLocked returns the endpoint that most closely matches the given +// id. +func (d *transportDemuxer) findEndpointLocked(eps *transportEndpoints, vv buffer.VectorisedView, id TransportEndpointID) *endpointsByNic { + if matchedEPs := d.findAllEndpointsLocked(eps, vv, id); len(matchedEPs) > 0 { + return matchedEPs[0] + } return nil } @@ -491,3 +492,7 @@ func (d *transportDemuxer) unregisterRawEndpoint(netProto tcpip.NetworkProtocolN } } } + +func isMulticastOrBroadcast(addr tcpip.Address) bool { + return addr == header.IPv4Broadcast || header.IsV4MulticastAddress(addr) || header.IsV6MulticastAddress(addr) +} diff --git a/pkg/tcpip/tcpip.go b/pkg/tcpip/tcpip.go index faaa4a4e3..70e7575f5 100644 --- a/pkg/tcpip/tcpip.go +++ b/pkg/tcpip/tcpip.go @@ -57,6 +57,9 @@ type Error struct { // String implements fmt.Stringer.String. func (e *Error) String() string { + if e == nil { + return "<nil>" + } return e.msg } @@ -1095,6 +1098,47 @@ func (a AddressWithPrefix) String() string { return fmt.Sprintf("%s/%d", a.Address, a.PrefixLen) } +// Subnet converts the address and prefix into a Subnet value and returns it. +func (a AddressWithPrefix) Subnet() Subnet { + addrLen := len(a.Address) + if a.PrefixLen <= 0 { + return Subnet{ + address: Address(strings.Repeat("\x00", addrLen)), + mask: AddressMask(strings.Repeat("\x00", addrLen)), + } + } + if a.PrefixLen >= addrLen*8 { + return Subnet{ + address: a.Address, + mask: AddressMask(strings.Repeat("\xff", addrLen)), + } + } + + sa := make([]byte, addrLen) + sm := make([]byte, addrLen) + n := uint(a.PrefixLen) + for i := 0; i < addrLen; i++ { + if n >= 8 { + sa[i] = a.Address[i] + sm[i] = 0xff + n -= 8 + continue + } + sm[i] = ^byte(0xff >> n) + sa[i] = a.Address[i] & sm[i] + n = 0 + } + + // For extra caution, call NewSubnet rather than directly creating the Subnet + // value. If that fails it indicates a serious bug in this code, so panic is + // in order. + s, err := NewSubnet(Address(sa), AddressMask(sm)) + if err != nil { + panic("invalid subnet: " + err.Error()) + } + return s +} + // ProtocolAddress is an address and the network protocol it is associated // with. type ProtocolAddress struct { diff --git a/pkg/tcpip/tcpip_test.go b/pkg/tcpip/tcpip_test.go index fb3a0a5ee..8c0aacffa 100644 --- a/pkg/tcpip/tcpip_test.go +++ b/pkg/tcpip/tcpip_test.go @@ -195,3 +195,34 @@ func TestStatsString(t *testing.T) { t.Logf(`got = fmt.Sprintf("%%+v", Stats{}.FillIn()) = %q`, got) } } + +func TestAddressWithPrefixSubnet(t *testing.T) { + tests := []struct { + addr Address + prefixLen int + subnetAddr Address + subnetMask AddressMask + }{ + {"\xaa\x55\x33\x42", -1, "\x00\x00\x00\x00", "\x00\x00\x00\x00"}, + {"\xaa\x55\x33\x42", 0, "\x00\x00\x00\x00", "\x00\x00\x00\x00"}, + {"\xaa\x55\x33\x42", 1, "\x80\x00\x00\x00", "\x80\x00\x00\x00"}, + {"\xaa\x55\x33\x42", 7, "\xaa\x00\x00\x00", "\xfe\x00\x00\x00"}, + {"\xaa\x55\x33\x42", 8, "\xaa\x00\x00\x00", "\xff\x00\x00\x00"}, + {"\xaa\x55\x33\x42", 24, "\xaa\x55\x33\x00", "\xff\xff\xff\x00"}, + {"\xaa\x55\x33\x42", 31, "\xaa\x55\x33\x42", "\xff\xff\xff\xfe"}, + {"\xaa\x55\x33\x42", 32, "\xaa\x55\x33\x42", "\xff\xff\xff\xff"}, + {"\xaa\x55\x33\x42", 33, "\xaa\x55\x33\x42", "\xff\xff\xff\xff"}, + } + for _, tt := range tests { + ap := AddressWithPrefix{Address: tt.addr, PrefixLen: tt.prefixLen} + gotSubnet := ap.Subnet() + wantSubnet, err := NewSubnet(tt.subnetAddr, tt.subnetMask) + if err != nil { + t.Error("NewSubnet(%q, %q) failed: %s", tt.subnetAddr, tt.subnetMask, err) + continue + } + if gotSubnet != wantSubnet { + t.Errorf("got subnet = %q, want = %q", gotSubnet, wantSubnet) + } + } +} diff --git a/pkg/tcpip/transport/udp/udp_test.go b/pkg/tcpip/transport/udp/udp_test.go index 5059ca22d..d1ba8d2ce 100644 --- a/pkg/tcpip/transport/udp/udp_test.go +++ b/pkg/tcpip/transport/udp/udp_test.go @@ -532,10 +532,11 @@ func TestBindToDeviceOption(t *testing.T) { } } -// testRead sends a packet of the given test flow into the stack by injecting it -// into the link endpoint. It then reads it from the UDP endpoint and verifies -// its correctness. -func testRead(c *testContext, flow testFlow) { +// testReadInternal sends a packet of the given test flow into the stack by +// injecting it into the link endpoint. It then attempts to read it from the +// UDP endpoint and depending on if this was expected to succeed verifies its +// correctness. +func testReadInternal(c *testContext, flow testFlow, packetShouldBeDropped bool) { c.t.Helper() payload := newPayload() @@ -553,27 +554,51 @@ func testRead(c *testContext, flow testFlow) { select { case <-ch: v, _, err = c.ep.Read(&addr) - if err != nil { - c.t.Fatalf("Read failed: %v", err) - } - case <-time.After(1 * time.Second): - c.t.Fatalf("Timed out waiting for data") + case <-time.After(300 * time.Millisecond): + if packetShouldBeDropped { + return // expected to time out + } + c.t.Fatal("timed out waiting for data") } } + if err != nil { + c.t.Fatal("Read failed:", err) + } + + if packetShouldBeDropped { + c.t.Fatalf("Read unexpectedly received data from %s", addr.Addr) + } + // Check the peer address. h := flow.header4Tuple(incoming) if addr.Addr != h.srcAddr.Addr { - c.t.Fatalf("Unexpected remote address: got %v, want %v", addr.Addr, h.srcAddr) + c.t.Fatalf("unexpected remote address: got %s, want %s", addr.Addr, h.srcAddr) } // Check the payload. if !bytes.Equal(payload, v) { - c.t.Fatalf("Bad payload: got %x, want %x", v, payload) + c.t.Fatalf("bad payload: got %x, want %x", v, payload) } } +// testRead sends a packet of the given test flow into the stack by injecting it +// into the link endpoint. It then reads it from the UDP endpoint and verifies +// its correctness. +func testRead(c *testContext, flow testFlow) { + c.t.Helper() + testReadInternal(c, flow, false /* packetShouldBeDropped */) +} + +// testFailingRead sends a packet of the given test flow into the stack by +// injecting it into the link endpoint. It then tries to read it from the UDP +// endpoint and expects this to fail. +func testFailingRead(c *testContext, flow testFlow) { + c.t.Helper() + testReadInternal(c, flow, true /* packetShouldBeDropped */) +} + func TestBindEphemeralPort(t *testing.T) { c := newDualTestContext(t, defaultMTU) defer c.cleanup() @@ -743,13 +768,17 @@ func TestReadOnBoundToMulticast(t *testing.T) { c.t.Fatal("SetSockOpt failed:", err) } + // Check that we receive multicast packets but not unicast or broadcast + // ones. testRead(c, flow) + testFailingRead(c, broadcast) + testFailingRead(c, unicastV4) }) } } // TestV4ReadOnBoundToBroadcast checks that an endpoint can bind to a broadcast -// address and receive broadcast data on it. +// address and can receive only broadcast data. func TestV4ReadOnBoundToBroadcast(t *testing.T) { for _, flow := range []testFlow{broadcast, broadcastIn6} { t.Run(fmt.Sprintf("flow:%s", flow), func(t *testing.T) { @@ -764,8 +793,31 @@ func TestV4ReadOnBoundToBroadcast(t *testing.T) { c.t.Fatalf("Bind failed: %s", err) } - // Test acceptance. + // Check that we receive broadcast packets but not unicast ones. + testRead(c, flow) + testFailingRead(c, unicastV4) + }) + } +} + +// TestV4ReadBroadcastOnBoundToWildcard checks that an endpoint can bind to ANY +// and receive broadcast and unicast data. +func TestV4ReadBroadcastOnBoundToWildcard(t *testing.T) { + for _, flow := range []testFlow{broadcast, broadcastIn6} { + t.Run(fmt.Sprintf("flow:%s", flow), func(t *testing.T) { + c := newDualTestContext(t, defaultMTU) + defer c.cleanup() + + c.createEndpointForFlow(flow) + + // Bind to wildcard. + if err := c.ep.Bind(tcpip.FullAddress{Port: stackPort}); err != nil { + c.t.Fatalf("Bind failed: %s (", err) + } + + // Check that we receive both broadcast and unicast packets. testRead(c, flow) + testRead(c, unicastV4) }) } } diff --git a/test/syscalls/linux/socket_ipv4_udp_unbound_external_networking.cc b/test/syscalls/linux/socket_ipv4_udp_unbound_external_networking.cc index c85ae30dc..8b8993d3d 100644 --- a/test/syscalls/linux/socket_ipv4_udp_unbound_external_networking.cc +++ b/test/syscalls/linux/socket_ipv4_udp_unbound_external_networking.cc @@ -42,6 +42,26 @@ TestAddress V4EmptyAddress() { return t; } +constexpr char kMulticastAddress[] = "224.0.2.1"; + +TestAddress V4Multicast() { + TestAddress t("V4Multicast"); + t.addr.ss_family = AF_INET; + t.addr_len = sizeof(sockaddr_in); + reinterpret_cast<sockaddr_in*>(&t.addr)->sin_addr.s_addr = + inet_addr(kMulticastAddress); + return t; +} + +TestAddress V4Broadcast() { + TestAddress t("V4Broadcast"); + t.addr.ss_family = AF_INET; + t.addr_len = sizeof(sockaddr_in); + reinterpret_cast<sockaddr_in*>(&t.addr)->sin_addr.s_addr = + htonl(INADDR_BROADCAST); + return t; +} + void IPv4UDPUnboundExternalNetworkingSocketTest::SetUp() { got_if_infos_ = false; @@ -116,7 +136,7 @@ TEST_P(IPv4UDPUnboundExternalNetworkingSocketTest, SetUDPBroadcast) { // Verifies that a broadcast UDP packet will arrive at all UDP sockets with // the destination port number. TEST_P(IPv4UDPUnboundExternalNetworkingSocketTest, - UDPBroadcastReceivedOnAllExpectedEndpoints) { + UDPBroadcastReceivedOnExpectedPort) { auto sender = ASSERT_NO_ERRNO_AND_VALUE(NewSocket()); auto rcvr1 = ASSERT_NO_ERRNO_AND_VALUE(NewSocket()); auto rcvr2 = ASSERT_NO_ERRNO_AND_VALUE(NewSocket()); @@ -136,51 +156,134 @@ TEST_P(IPv4UDPUnboundExternalNetworkingSocketTest, sizeof(kSockOptOn)), SyscallSucceedsWithValue(0)); - sockaddr_in rcv_addr = {}; - socklen_t rcv_addr_sz = sizeof(rcv_addr); - rcv_addr.sin_family = AF_INET; - rcv_addr.sin_addr.s_addr = htonl(INADDR_ANY); - ASSERT_THAT(bind(rcvr1->get(), reinterpret_cast<struct sockaddr*>(&rcv_addr), - rcv_addr_sz), + // Bind the first socket to the ANY address and let the system assign a port. + auto rcv1_addr = V4Any(); + ASSERT_THAT(bind(rcvr1->get(), reinterpret_cast<sockaddr*>(&rcv1_addr.addr), + rcv1_addr.addr_len), SyscallSucceedsWithValue(0)); // Retrieve port number from first socket so that it can be bound to the // second socket. - rcv_addr = {}; + socklen_t rcv_addr_sz = rcv1_addr.addr_len; ASSERT_THAT( - getsockname(rcvr1->get(), reinterpret_cast<struct sockaddr*>(&rcv_addr), + getsockname(rcvr1->get(), reinterpret_cast<sockaddr*>(&rcv1_addr.addr), &rcv_addr_sz), SyscallSucceedsWithValue(0)); - ASSERT_THAT(bind(rcvr2->get(), reinterpret_cast<struct sockaddr*>(&rcv_addr), + EXPECT_EQ(rcv_addr_sz, rcv1_addr.addr_len); + auto port = reinterpret_cast<sockaddr_in*>(&rcv1_addr.addr)->sin_port; + + // Bind the second socket to the same address:port as the first. + ASSERT_THAT(bind(rcvr2->get(), reinterpret_cast<sockaddr*>(&rcv1_addr.addr), rcv_addr_sz), SyscallSucceedsWithValue(0)); // Bind the non-receiving socket to an ephemeral port. - sockaddr_in norcv_addr = {}; - norcv_addr.sin_family = AF_INET; - norcv_addr.sin_addr.s_addr = htonl(INADDR_ANY); + auto norecv_addr = V4Any(); + ASSERT_THAT(bind(norcv->get(), reinterpret_cast<sockaddr*>(&norecv_addr.addr), + norecv_addr.addr_len), + SyscallSucceedsWithValue(0)); + + // Broadcast a test message. + auto dst_addr = V4Broadcast(); + reinterpret_cast<sockaddr_in*>(&dst_addr.addr)->sin_port = port; + constexpr char kTestMsg[] = "hello, world"; + EXPECT_THAT( + sendto(sender->get(), kTestMsg, sizeof(kTestMsg), 0, + reinterpret_cast<sockaddr*>(&dst_addr.addr), dst_addr.addr_len), + SyscallSucceedsWithValue(sizeof(kTestMsg))); + + // Verify that the receiving sockets received the test message. + char buf[sizeof(kTestMsg)] = {}; + EXPECT_THAT(recv(rcvr1->get(), buf, sizeof(buf), 0), + SyscallSucceedsWithValue(sizeof(kTestMsg))); + EXPECT_EQ(0, memcmp(buf, kTestMsg, sizeof(kTestMsg))); + memset(buf, 0, sizeof(buf)); + EXPECT_THAT(recv(rcvr2->get(), buf, sizeof(buf), 0), + SyscallSucceedsWithValue(sizeof(kTestMsg))); + EXPECT_EQ(0, memcmp(buf, kTestMsg, sizeof(kTestMsg))); + + // Verify that the non-receiving socket did not receive the test message. + memset(buf, 0, sizeof(buf)); + EXPECT_THAT(RetryEINTR(recv)(norcv->get(), buf, sizeof(buf), MSG_DONTWAIT), + SyscallFailsWithErrno(EAGAIN)); +} + +// Verifies that a broadcast UDP packet will arrive at all UDP sockets bound to +// the destination port number and either INADDR_ANY or INADDR_BROADCAST, but +// not a unicast address. +TEST_P(IPv4UDPUnboundExternalNetworkingSocketTest, + UDPBroadcastReceivedOnExpectedAddresses) { + // FIXME(b/137899561): Linux instance for syscall tests sometimes misses its + // IPv4 address on eth0. + SKIP_IF(!got_if_infos_); + + auto sender = ASSERT_NO_ERRNO_AND_VALUE(NewSocket()); + auto rcvr1 = ASSERT_NO_ERRNO_AND_VALUE(NewSocket()); + auto rcvr2 = ASSERT_NO_ERRNO_AND_VALUE(NewSocket()); + auto norcv = ASSERT_NO_ERRNO_AND_VALUE(NewSocket()); + + // Enable SO_BROADCAST on the sending socket. + ASSERT_THAT(setsockopt(sender->get(), SOL_SOCKET, SO_BROADCAST, &kSockOptOn, + sizeof(kSockOptOn)), + SyscallSucceedsWithValue(0)); + + // Enable SO_REUSEPORT on all sockets so that they may all be bound to the + // broadcast messages destination port. + ASSERT_THAT(setsockopt(rcvr1->get(), SOL_SOCKET, SO_REUSEPORT, &kSockOptOn, + sizeof(kSockOptOn)), + SyscallSucceedsWithValue(0)); + ASSERT_THAT(setsockopt(rcvr2->get(), SOL_SOCKET, SO_REUSEPORT, &kSockOptOn, + sizeof(kSockOptOn)), + SyscallSucceedsWithValue(0)); + ASSERT_THAT(setsockopt(norcv->get(), SOL_SOCKET, SO_REUSEPORT, &kSockOptOn, + sizeof(kSockOptOn)), + SyscallSucceedsWithValue(0)); + + // Bind the first socket the ANY address and let the system assign a port. + auto rcv1_addr = V4Any(); + ASSERT_THAT(bind(rcvr1->get(), reinterpret_cast<sockaddr*>(&rcv1_addr.addr), + rcv1_addr.addr_len), + SyscallSucceedsWithValue(0)); + // Retrieve port number from first socket so that it can be bound to the + // second socket. + socklen_t rcv_addr_sz = rcv1_addr.addr_len; ASSERT_THAT( - bind(norcv->get(), reinterpret_cast<struct sockaddr*>(&norcv_addr), - sizeof(norcv_addr)), + getsockname(rcvr1->get(), reinterpret_cast<sockaddr*>(&rcv1_addr.addr), + &rcv_addr_sz), SyscallSucceedsWithValue(0)); + EXPECT_EQ(rcv_addr_sz, rcv1_addr.addr_len); + auto port = reinterpret_cast<sockaddr_in*>(&rcv1_addr.addr)->sin_port; + + // Bind the second socket to the broadcast address. + auto rcv2_addr = V4Broadcast(); + reinterpret_cast<sockaddr_in*>(&rcv2_addr.addr)->sin_port = port; + ASSERT_THAT(bind(rcvr2->get(), reinterpret_cast<sockaddr*>(&rcv2_addr.addr), + rcv2_addr.addr_len), + SyscallSucceedsWithValue(0)); + + // Bind the non-receiving socket to the unicast ethernet address. + auto norecv_addr = rcv1_addr; + reinterpret_cast<sockaddr_in*>(&norecv_addr.addr)->sin_addr = + eth_if_sin_addr_; + ASSERT_THAT(bind(norcv->get(), reinterpret_cast<sockaddr*>(&norecv_addr.addr), + norecv_addr.addr_len), + SyscallSucceedsWithValue(0)); // Broadcast a test message. - sockaddr_in dst_addr = {}; - dst_addr.sin_family = AF_INET; - dst_addr.sin_addr.s_addr = htonl(INADDR_BROADCAST); - dst_addr.sin_port = rcv_addr.sin_port; + auto dst_addr = V4Broadcast(); + reinterpret_cast<sockaddr_in*>(&dst_addr.addr)->sin_port = port; constexpr char kTestMsg[] = "hello, world"; EXPECT_THAT( sendto(sender->get(), kTestMsg, sizeof(kTestMsg), 0, - reinterpret_cast<struct sockaddr*>(&dst_addr), sizeof(dst_addr)), + reinterpret_cast<sockaddr*>(&dst_addr.addr), dst_addr.addr_len), SyscallSucceedsWithValue(sizeof(kTestMsg))); // Verify that the receiving sockets received the test message. char buf[sizeof(kTestMsg)] = {}; - EXPECT_THAT(read(rcvr1->get(), buf, sizeof(buf)), + EXPECT_THAT(recv(rcvr1->get(), buf, sizeof(buf), 0), SyscallSucceedsWithValue(sizeof(kTestMsg))); EXPECT_EQ(0, memcmp(buf, kTestMsg, sizeof(kTestMsg))); memset(buf, 0, sizeof(buf)); - EXPECT_THAT(read(rcvr2->get(), buf, sizeof(buf)), + EXPECT_THAT(recv(rcvr2->get(), buf, sizeof(buf), 0), SyscallSucceedsWithValue(sizeof(kTestMsg))); EXPECT_EQ(0, memcmp(buf, kTestMsg, sizeof(kTestMsg))); @@ -190,10 +293,12 @@ TEST_P(IPv4UDPUnboundExternalNetworkingSocketTest, SyscallFailsWithErrno(EAGAIN)); } -// Verifies that a UDP broadcast sent via the loopback interface is not received -// by the sender. +// Verifies that a UDP broadcast can be sent and then received back on the same +// socket that is bound to the broadcast address (255.255.255.255). +// FIXME(b/141938460): This can be combined with the next test +// (UDPBroadcastSendRecvOnSocketBoundToAny). TEST_P(IPv4UDPUnboundExternalNetworkingSocketTest, - UDPBroadcastViaLoopbackFails) { + UDPBroadcastSendRecvOnSocketBoundToBroadcast) { auto sender = ASSERT_NO_ERRNO_AND_VALUE(NewSocket()); // Enable SO_BROADCAST. @@ -201,33 +306,73 @@ TEST_P(IPv4UDPUnboundExternalNetworkingSocketTest, sizeof(kSockOptOn)), SyscallSucceedsWithValue(0)); - // Bind the sender to the loopback interface. - sockaddr_in src = {}; - socklen_t src_sz = sizeof(src); - src.sin_family = AF_INET; - src.sin_addr.s_addr = htonl(INADDR_LOOPBACK); - ASSERT_THAT( - bind(sender->get(), reinterpret_cast<struct sockaddr*>(&src), src_sz), - SyscallSucceedsWithValue(0)); + // Bind the sender to the broadcast address. + auto src_addr = V4Broadcast(); + ASSERT_THAT(bind(sender->get(), reinterpret_cast<sockaddr*>(&src_addr.addr), + src_addr.addr_len), + SyscallSucceedsWithValue(0)); + socklen_t src_sz = src_addr.addr_len; ASSERT_THAT(getsockname(sender->get(), - reinterpret_cast<struct sockaddr*>(&src), &src_sz), + reinterpret_cast<sockaddr*>(&src_addr.addr), &src_sz), SyscallSucceedsWithValue(0)); - ASSERT_EQ(src.sin_addr.s_addr, htonl(INADDR_LOOPBACK)); + EXPECT_EQ(src_sz, src_addr.addr_len); // Send the message. - sockaddr_in dst = {}; - dst.sin_family = AF_INET; - dst.sin_addr.s_addr = htonl(INADDR_BROADCAST); - dst.sin_port = src.sin_port; + auto dst_addr = V4Broadcast(); + reinterpret_cast<sockaddr_in*>(&dst_addr.addr)->sin_port = + reinterpret_cast<sockaddr_in*>(&src_addr.addr)->sin_port; constexpr char kTestMsg[] = "hello, world"; - EXPECT_THAT(sendto(sender->get(), kTestMsg, sizeof(kTestMsg), 0, - reinterpret_cast<struct sockaddr*>(&dst), sizeof(dst)), + EXPECT_THAT( + sendto(sender->get(), kTestMsg, sizeof(kTestMsg), 0, + reinterpret_cast<sockaddr*>(&dst_addr.addr), dst_addr.addr_len), + SyscallSucceedsWithValue(sizeof(kTestMsg))); + + // Verify that the message was received. + char buf[sizeof(kTestMsg)] = {}; + EXPECT_THAT(RetryEINTR(recv)(sender->get(), buf, sizeof(buf), 0), SyscallSucceedsWithValue(sizeof(kTestMsg))); + EXPECT_EQ(0, memcmp(buf, kTestMsg, sizeof(kTestMsg))); +} + +// Verifies that a UDP broadcast can be sent and then received back on the same +// socket that is bound to the ANY address (0.0.0.0). +// FIXME(b/141938460): This can be combined with the previous test +// (UDPBroadcastSendRecvOnSocketBoundToBroadcast). +TEST_P(IPv4UDPUnboundExternalNetworkingSocketTest, + UDPBroadcastSendRecvOnSocketBoundToAny) { + auto sender = ASSERT_NO_ERRNO_AND_VALUE(NewSocket()); - // Verify that the message was not received by the sender (loopback). + // Enable SO_BROADCAST. + ASSERT_THAT(setsockopt(sender->get(), SOL_SOCKET, SO_BROADCAST, &kSockOptOn, + sizeof(kSockOptOn)), + SyscallSucceedsWithValue(0)); + + // Bind the sender to the ANY address. + auto src_addr = V4Any(); + ASSERT_THAT(bind(sender->get(), reinterpret_cast<sockaddr*>(&src_addr.addr), + src_addr.addr_len), + SyscallSucceedsWithValue(0)); + socklen_t src_sz = src_addr.addr_len; + ASSERT_THAT(getsockname(sender->get(), + reinterpret_cast<sockaddr*>(&src_addr.addr), &src_sz), + SyscallSucceedsWithValue(0)); + EXPECT_EQ(src_sz, src_addr.addr_len); + + // Send the message. + auto dst_addr = V4Broadcast(); + reinterpret_cast<sockaddr_in*>(&dst_addr.addr)->sin_port = + reinterpret_cast<sockaddr_in*>(&src_addr.addr)->sin_port; + constexpr char kTestMsg[] = "hello, world"; + EXPECT_THAT( + sendto(sender->get(), kTestMsg, sizeof(kTestMsg), 0, + reinterpret_cast<sockaddr*>(&dst_addr.addr), dst_addr.addr_len), + SyscallSucceedsWithValue(sizeof(kTestMsg))); + + // Verify that the message was received. char buf[sizeof(kTestMsg)] = {}; - EXPECT_THAT(RetryEINTR(recv)(sender->get(), buf, sizeof(buf), MSG_DONTWAIT), - SyscallFailsWithErrno(EAGAIN)); + EXPECT_THAT(RetryEINTR(recv)(sender->get(), buf, sizeof(buf), 0), + SyscallSucceedsWithValue(sizeof(kTestMsg))); + EXPECT_EQ(0, memcmp(buf, kTestMsg, sizeof(kTestMsg))); } // Verifies that a UDP broadcast fails to send on a socket with SO_BROADCAST @@ -237,15 +382,12 @@ TEST_P(IPv4UDPUnboundExternalNetworkingSocketTest, TestSendBroadcast) { // Broadcast a test message without having enabled SO_BROADCAST on the sending // socket. - sockaddr_in addr = {}; - socklen_t addr_sz = sizeof(addr); - addr.sin_family = AF_INET; - addr.sin_port = htons(12345); - addr.sin_addr.s_addr = htonl(INADDR_BROADCAST); + auto addr = V4Broadcast(); + reinterpret_cast<sockaddr_in*>(&addr.addr)->sin_port = htons(12345); constexpr char kTestMsg[] = "hello, world"; EXPECT_THAT(sendto(sender->get(), kTestMsg, sizeof(kTestMsg), 0, - reinterpret_cast<struct sockaddr*>(&addr), addr_sz), + reinterpret_cast<sockaddr*>(&addr.addr), addr.addr_len), SyscallFailsWithErrno(EACCES)); } @@ -274,21 +416,10 @@ TEST_P(IPv4UDPUnboundExternalNetworkingSocketTest, TestSendUnicastOnUnbound) { reinterpret_cast<struct sockaddr*>(&addr), addr_sz), SyscallSucceedsWithValue(sizeof(kTestMsg))); char buf[sizeof(kTestMsg)] = {}; - ASSERT_THAT(read(rcvr->get(), buf, sizeof(buf)), + ASSERT_THAT(recv(rcvr->get(), buf, sizeof(buf), 0), SyscallSucceedsWithValue(sizeof(kTestMsg))); } -constexpr char kMulticastAddress[] = "224.0.2.1"; - -TestAddress V4Multicast() { - TestAddress t("V4Multicast"); - t.addr.ss_family = AF_INET; - t.addr_len = sizeof(sockaddr_in); - reinterpret_cast<sockaddr_in*>(&t.addr)->sin_addr.s_addr = - inet_addr(kMulticastAddress); - return t; -} - // Check that multicast packets won't be delivered to the sending socket with no // set interface or group membership. TEST_P(IPv4UDPUnboundExternalNetworkingSocketTest, @@ -609,8 +740,9 @@ TEST_P(IPv4UDPUnboundExternalNetworkingSocketTest, } // Check that two sockets can join the same multicast group at the same time, -// and both will receive data on it. -TEST_P(IPv4UDPUnboundExternalNetworkingSocketTest, TestSendMulticastToTwo) { +// and both will receive data on it when bound to the ANY address. +TEST_P(IPv4UDPUnboundExternalNetworkingSocketTest, + TestSendMulticastToTwoBoundToAny) { auto sender = ASSERT_NO_ERRNO_AND_VALUE(NewSocket()); std::unique_ptr<FileDescriptor> receivers[2] = { ASSERT_NO_ERRNO_AND_VALUE(NewSocket()), @@ -624,8 +756,72 @@ TEST_P(IPv4UDPUnboundExternalNetworkingSocketTest, TestSendMulticastToTwo) { ASSERT_THAT(setsockopt(receiver->get(), SOL_SOCKET, SO_REUSEPORT, &kSockOptOn, sizeof(kSockOptOn)), SyscallSucceeds()); - // Bind the receiver to the v4 any address to ensure that we can receive the - // multicast packet. + // Bind to ANY to receive multicast packets. + ASSERT_THAT( + bind(receiver->get(), reinterpret_cast<sockaddr*>(&receiver_addr.addr), + receiver_addr.addr_len), + SyscallSucceeds()); + socklen_t receiver_addr_len = receiver_addr.addr_len; + ASSERT_THAT(getsockname(receiver->get(), + reinterpret_cast<sockaddr*>(&receiver_addr.addr), + &receiver_addr_len), + SyscallSucceeds()); + EXPECT_EQ(receiver_addr_len, receiver_addr.addr_len); + EXPECT_EQ( + htonl(INADDR_ANY), + reinterpret_cast<sockaddr_in*>(&receiver_addr.addr)->sin_addr.s_addr); + // On the first iteration, save the port we are bound to. On the second + // iteration, verify the port is the same as the one from the first + // iteration. In other words, both sockets listen on the same port. + if (bound_port == 0) { + bound_port = + reinterpret_cast<sockaddr_in*>(&receiver_addr.addr)->sin_port; + } else { + EXPECT_EQ(bound_port, + reinterpret_cast<sockaddr_in*>(&receiver_addr.addr)->sin_port); + } + + // Register to receive multicast packets. + ASSERT_THAT(setsockopt(receiver->get(), IPPROTO_IP, IP_ADD_MEMBERSHIP, + &group, sizeof(group)), + SyscallSucceeds()); + } + + // Send a multicast packet to the group and verify both receivers get it. + auto send_addr = V4Multicast(); + reinterpret_cast<sockaddr_in*>(&send_addr.addr)->sin_port = bound_port; + char send_buf[200]; + RandomizeBuffer(send_buf, sizeof(send_buf)); + ASSERT_THAT(RetryEINTR(sendto)(sender->get(), send_buf, sizeof(send_buf), 0, + reinterpret_cast<sockaddr*>(&send_addr.addr), + send_addr.addr_len), + SyscallSucceedsWithValue(sizeof(send_buf))); + for (auto& receiver : receivers) { + char recv_buf[sizeof(send_buf)] = {}; + ASSERT_THAT( + RetryEINTR(recv)(receiver->get(), recv_buf, sizeof(recv_buf), 0), + SyscallSucceedsWithValue(sizeof(recv_buf))); + EXPECT_EQ(0, memcmp(send_buf, recv_buf, sizeof(send_buf))); + } +} + +// Check that two sockets can join the same multicast group at the same time, +// and both will receive data on it when bound to the multicast address. +TEST_P(IPv4UDPUnboundExternalNetworkingSocketTest, + TestSendMulticastToTwoBoundToMulticastAddress) { + auto sender = ASSERT_NO_ERRNO_AND_VALUE(NewSocket()); + std::unique_ptr<FileDescriptor> receivers[2] = { + ASSERT_NO_ERRNO_AND_VALUE(NewSocket()), + ASSERT_NO_ERRNO_AND_VALUE(NewSocket())}; + + ip_mreq group = {}; + group.imr_multiaddr.s_addr = inet_addr(kMulticastAddress); + auto receiver_addr = V4Multicast(); + int bound_port = 0; + for (auto& receiver : receivers) { + ASSERT_THAT(setsockopt(receiver->get(), SOL_SOCKET, SO_REUSEPORT, + &kSockOptOn, sizeof(kSockOptOn)), + SyscallSucceeds()); ASSERT_THAT( bind(receiver->get(), reinterpret_cast<sockaddr*>(&receiver_addr.addr), receiver_addr.addr_len), @@ -636,6 +832,9 @@ TEST_P(IPv4UDPUnboundExternalNetworkingSocketTest, TestSendMulticastToTwo) { &receiver_addr_len), SyscallSucceeds()); EXPECT_EQ(receiver_addr_len, receiver_addr.addr_len); + EXPECT_EQ( + inet_addr(kMulticastAddress), + reinterpret_cast<sockaddr_in*>(&receiver_addr.addr)->sin_addr.s_addr); // On the first iteration, save the port we are bound to. On the second // iteration, verify the port is the same as the one from the first // iteration. In other words, both sockets listen on the same port. @@ -643,6 +842,83 @@ TEST_P(IPv4UDPUnboundExternalNetworkingSocketTest, TestSendMulticastToTwo) { bound_port = reinterpret_cast<sockaddr_in*>(&receiver_addr.addr)->sin_port; } else { + EXPECT_EQ( + inet_addr(kMulticastAddress), + reinterpret_cast<sockaddr_in*>(&receiver_addr.addr)->sin_addr.s_addr); + EXPECT_EQ(bound_port, + reinterpret_cast<sockaddr_in*>(&receiver_addr.addr)->sin_port); + } + + // Register to receive multicast packets. + ASSERT_THAT(setsockopt(receiver->get(), IPPROTO_IP, IP_ADD_MEMBERSHIP, + &group, sizeof(group)), + SyscallSucceeds()); + } + + // Send a multicast packet to the group and verify both receivers get it. + auto send_addr = V4Multicast(); + reinterpret_cast<sockaddr_in*>(&send_addr.addr)->sin_port = bound_port; + char send_buf[200]; + RandomizeBuffer(send_buf, sizeof(send_buf)); + ASSERT_THAT(RetryEINTR(sendto)(sender->get(), send_buf, sizeof(send_buf), 0, + reinterpret_cast<sockaddr*>(&send_addr.addr), + send_addr.addr_len), + SyscallSucceedsWithValue(sizeof(send_buf))); + for (auto& receiver : receivers) { + char recv_buf[sizeof(send_buf)] = {}; + ASSERT_THAT( + RetryEINTR(recv)(receiver->get(), recv_buf, sizeof(recv_buf), 0), + SyscallSucceedsWithValue(sizeof(recv_buf))); + EXPECT_EQ(0, memcmp(send_buf, recv_buf, sizeof(send_buf))); + } +} + +// Check that two sockets can join the same multicast group at the same time, +// and with one bound to the wildcard address and the other bound to the +// multicast address, both will receive data. +TEST_P(IPv4UDPUnboundExternalNetworkingSocketTest, + TestSendMulticastToTwoBoundToAnyAndMulticastAddress) { + auto sender = ASSERT_NO_ERRNO_AND_VALUE(NewSocket()); + std::unique_ptr<FileDescriptor> receivers[2] = { + ASSERT_NO_ERRNO_AND_VALUE(NewSocket()), + ASSERT_NO_ERRNO_AND_VALUE(NewSocket())}; + + ip_mreq group = {}; + group.imr_multiaddr.s_addr = inet_addr(kMulticastAddress); + // The first receiver binds to the wildcard address. + auto receiver_addr = V4Any(); + int bound_port = 0; + for (auto& receiver : receivers) { + ASSERT_THAT(setsockopt(receiver->get(), SOL_SOCKET, SO_REUSEPORT, + &kSockOptOn, sizeof(kSockOptOn)), + SyscallSucceeds()); + ASSERT_THAT( + bind(receiver->get(), reinterpret_cast<sockaddr*>(&receiver_addr.addr), + receiver_addr.addr_len), + SyscallSucceeds()); + socklen_t receiver_addr_len = receiver_addr.addr_len; + ASSERT_THAT(getsockname(receiver->get(), + reinterpret_cast<sockaddr*>(&receiver_addr.addr), + &receiver_addr_len), + SyscallSucceeds()); + EXPECT_EQ(receiver_addr_len, receiver_addr.addr_len); + // On the first iteration, save the port we are bound to and change the + // receiver address from V4Any to V4Multicast so the second receiver binds + // to that. On the second iteration, verify the port is the same as the one + // from the first iteration but the address is different. + if (bound_port == 0) { + EXPECT_EQ( + htonl(INADDR_ANY), + reinterpret_cast<sockaddr_in*>(&receiver_addr.addr)->sin_addr.s_addr); + bound_port = + reinterpret_cast<sockaddr_in*>(&receiver_addr.addr)->sin_port; + receiver_addr = V4Multicast(); + reinterpret_cast<sockaddr_in*>(&receiver_addr.addr)->sin_port = + bound_port; + } else { + EXPECT_EQ( + inet_addr(kMulticastAddress), + reinterpret_cast<sockaddr_in*>(&receiver_addr.addr)->sin_addr.s_addr); EXPECT_EQ(bound_port, reinterpret_cast<sockaddr_in*>(&receiver_addr.addr)->sin_port); } |