diff options
Diffstat (limited to 'pkg')
-rw-r--r-- | pkg/tcpip/stack/nic.go | 193 | ||||
-rw-r--r-- | pkg/tcpip/stack/route.go | 10 | ||||
-rw-r--r-- | pkg/tcpip/stack/stack_test.go | 507 |
3 files changed, 545 insertions, 165 deletions
diff --git a/pkg/tcpip/stack/nic.go b/pkg/tcpip/stack/nic.go index 4ef85bdfb..04b63d783 100644 --- a/pkg/tcpip/stack/nic.go +++ b/pkg/tcpip/stack/nic.go @@ -139,7 +139,7 @@ func (n *NIC) getMainNICAddress(protocol tcpip.NetworkProtocolNumber) (tcpip.Add if list, ok := n.primary[protocol]; ok { for e := list.Front(); e != nil; e = e.Next() { ref := e.(*referencedNetworkEndpoint) - if ref.holdsInsertRef && ref.tryIncRef() { + if ref.kind == permanent && ref.tryIncRef() { r = ref break } @@ -178,7 +178,7 @@ func (n *NIC) primaryEndpoint(protocol tcpip.NetworkProtocolNumber) *referencedN case header.IPv4Broadcast, header.IPv4Any: continue } - if r.tryIncRef() { + if r.isValidForOutgoing() && r.tryIncRef() { return r } } @@ -197,20 +197,32 @@ func (n *NIC) findEndpoint(protocol tcpip.NetworkProtocolNumber, address tcpip.A // getRefEpOrCreateTemp returns the referenced network endpoint for the given // protocol and address. If none exists a temporary one may be created if -// requested. -func (n *NIC) getRefOrCreateTemp(protocol tcpip.NetworkProtocolNumber, address tcpip.Address, peb PrimaryEndpointBehavior, allowTemp bool) *referencedNetworkEndpoint { +// we are in promiscuous mode or spoofing. +func (n *NIC) getRefOrCreateTemp(protocol tcpip.NetworkProtocolNumber, address tcpip.Address, peb PrimaryEndpointBehavior, spoofingOrPromiscuous bool) *referencedNetworkEndpoint { id := NetworkEndpointID{address} n.mu.RLock() - if ref, ok := n.endpoints[id]; ok && ref.tryIncRef() { - n.mu.RUnlock() - return ref + if ref, ok := n.endpoints[id]; ok { + // An endpoint with this id exists, check if it can be used and return it. + switch ref.kind { + case permanentExpired: + if !spoofingOrPromiscuous { + n.mu.RUnlock() + return nil + } + fallthrough + case temporary, permanent: + if ref.tryIncRef() { + n.mu.RUnlock() + return ref + } + } } - // The address was not found, create a temporary one if requested by the - // caller or if the address is found in the NIC's subnets. - createTempEP := allowTemp + // A usable reference was not found, create a temporary one if requested by + // the caller or if the address is found in the NIC's subnets. + createTempEP := spoofingOrPromiscuous if !createTempEP { for _, sn := range n.subnets { if sn.Contains(address) { @@ -230,34 +242,68 @@ func (n *NIC) getRefOrCreateTemp(protocol tcpip.NetworkProtocolNumber, address t // endpoint, create a new "temporary" endpoint. It will only exist while // there's a route through it. n.mu.Lock() - if ref, ok := n.endpoints[id]; ok && ref.tryIncRef() { - n.mu.Unlock() - return ref + if ref, ok := n.endpoints[id]; ok { + // No need to check the type as we are ok with expired endpoints at this + // point. + if ref.tryIncRef() { + n.mu.Unlock() + return ref + } + // tryIncRef failing means the endpoint is scheduled to be removed once the + // lock is released. Remove it here so we can create a new (temporary) one. + // The removal logic waiting for the lock handles this case. + n.removeEndpointLocked(ref) } + // Add a new temporary endpoint. netProto, ok := n.stack.networkProtocols[protocol] if !ok { n.mu.Unlock() return nil } - ref, _ := n.addAddressLocked(tcpip.ProtocolAddress{ Protocol: protocol, AddressWithPrefix: tcpip.AddressWithPrefix{ Address: address, PrefixLen: netProto.DefaultPrefixLen(), }, - }, peb, true) - - if ref != nil { - ref.holdsInsertRef = false - } + }, peb, temporary) n.mu.Unlock() return ref } -func (n *NIC) addAddressLocked(protocolAddress tcpip.ProtocolAddress, peb PrimaryEndpointBehavior, replace bool) (*referencedNetworkEndpoint, *tcpip.Error) { +func (n *NIC) addPermanentAddressLocked(protocolAddress tcpip.ProtocolAddress, peb PrimaryEndpointBehavior) (*referencedNetworkEndpoint, *tcpip.Error) { + id := NetworkEndpointID{protocolAddress.AddressWithPrefix.Address} + if ref, ok := n.endpoints[id]; ok { + switch ref.kind { + case permanent: + // The NIC already have a permanent endpoint with that address. + return nil, tcpip.ErrDuplicateAddress + case permanentExpired, temporary: + // Promote the endpoint to become permanent. + if ref.tryIncRef() { + ref.kind = permanent + return ref, nil + } + // tryIncRef failing means the endpoint is scheduled to be removed once + // the lock is released. Remove it here so we can create a new + // (permanent) one. The removal logic waiting for the lock handles this + // case. + n.removeEndpointLocked(ref) + } + } + return n.addAddressLocked(protocolAddress, peb, permanent) +} + +func (n *NIC) addAddressLocked(protocolAddress tcpip.ProtocolAddress, peb PrimaryEndpointBehavior, kind networkEndpointKind) (*referencedNetworkEndpoint, *tcpip.Error) { + // Sanity check. + id := NetworkEndpointID{protocolAddress.AddressWithPrefix.Address} + if _, ok := n.endpoints[id]; ok { + // Endpoint already exists. + return nil, tcpip.ErrDuplicateAddress + } + netProto, ok := n.stack.networkProtocols[protocolAddress.Protocol] if !ok { return nil, tcpip.ErrUnknownProtocol @@ -268,22 +314,12 @@ func (n *NIC) addAddressLocked(protocolAddress tcpip.ProtocolAddress, peb Primar if err != nil { return nil, err } - - id := *ep.ID() - if ref, ok := n.endpoints[id]; ok { - if !replace { - return nil, tcpip.ErrDuplicateAddress - } - - n.removeEndpointLocked(ref) - } - ref := &referencedNetworkEndpoint{ - refs: 1, - ep: ep, - nic: n, - protocol: protocolAddress.Protocol, - holdsInsertRef: true, + refs: 1, + ep: ep, + nic: n, + protocol: protocolAddress.Protocol, + kind: kind, } // Set up cache if link address resolution exists for this protocol. @@ -316,7 +352,7 @@ func (n *NIC) addAddressLocked(protocolAddress tcpip.ProtocolAddress, peb Primar func (n *NIC) AddAddress(protocolAddress tcpip.ProtocolAddress, peb PrimaryEndpointBehavior) *tcpip.Error { // Add the endpoint. n.mu.Lock() - _, err := n.addAddressLocked(protocolAddress, peb, false) + _, err := n.addPermanentAddressLocked(protocolAddress, peb) n.mu.Unlock() return err @@ -328,6 +364,12 @@ func (n *NIC) Addresses() []tcpip.ProtocolAddress { defer n.mu.RUnlock() 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 + // prevent the caller from using those. + switch ref.kind { + case permanentExpired, temporary: + continue + } addrs = append(addrs, tcpip.ProtocolAddress{ Protocol: ref.protocol, AddressWithPrefix: tcpip.AddressWithPrefix{ @@ -393,13 +435,16 @@ func (n *NIC) Subnets() []tcpip.Subnet { func (n *NIC) removeEndpointLocked(r *referencedNetworkEndpoint) { id := *r.ep.ID() - // Nothing to do if the reference has already been replaced with a - // different one. + // Nothing to do if the reference has already been replaced with a different + // one. This happens in the case where 1) this endpoint's ref count hit zero + // and was waiting (on the lock) to be removed and 2) the same address was + // re-added in the meantime by removing this endpoint from the list and + // adding a new one. if n.endpoints[id] != r { return } - if r.holdsInsertRef { + if r.kind == permanent { panic("Reference count dropped to zero before being removed") } @@ -418,14 +463,13 @@ func (n *NIC) removeEndpoint(r *referencedNetworkEndpoint) { n.mu.Unlock() } -func (n *NIC) removeAddressLocked(addr tcpip.Address) *tcpip.Error { +func (n *NIC) removePermanentAddressLocked(addr tcpip.Address) *tcpip.Error { r := n.endpoints[NetworkEndpointID{addr}] - if r == nil || !r.holdsInsertRef { + if r == nil || r.kind != permanent { return tcpip.ErrBadLocalAddress } - r.holdsInsertRef = false - + r.kind = permanentExpired r.decRefLocked() return nil @@ -435,7 +479,7 @@ func (n *NIC) removeAddressLocked(addr tcpip.Address) *tcpip.Error { func (n *NIC) RemoveAddress(addr tcpip.Address) *tcpip.Error { n.mu.Lock() defer n.mu.Unlock() - return n.removeAddressLocked(addr) + return n.removePermanentAddressLocked(addr) } // joinGroup adds a new endpoint for the given multicast address, if none @@ -451,13 +495,13 @@ func (n *NIC) joinGroup(protocol tcpip.NetworkProtocolNumber, addr tcpip.Address if !ok { return tcpip.ErrUnknownProtocol } - if _, err := n.addAddressLocked(tcpip.ProtocolAddress{ + if _, err := n.addPermanentAddressLocked(tcpip.ProtocolAddress{ Protocol: protocol, AddressWithPrefix: tcpip.AddressWithPrefix{ Address: addr, PrefixLen: netProto.DefaultPrefixLen(), }, - }, NeverPrimaryEndpoint, false); err != nil { + }, NeverPrimaryEndpoint); err != nil { return err } } @@ -479,7 +523,7 @@ func (n *NIC) leaveGroup(addr tcpip.Address) *tcpip.Error { return tcpip.ErrBadLocalAddress case 1: // This is the last one, clean up. - if err := n.removeAddressLocked(addr); err != nil { + if err := n.removePermanentAddressLocked(addr); err != nil { return err } } @@ -521,7 +565,7 @@ func (n *NIC) DeliverNetworkPacket(linkEP LinkEndpoint, remote, _ tcpip.LinkAddr // n.endpoints is mutex protected so acquire lock. n.mu.RLock() for _, ref := range n.endpoints { - if ref.protocol == header.IPv4ProtocolNumber && ref.tryIncRef() { + if ref.isValidForIncoming() && ref.protocol == header.IPv4ProtocolNumber && ref.tryIncRef() { r := makeRoute(protocol, dst, src, linkEP.LinkAddress(), ref, false /* handleLocal */, false /* multicastLoop */) r.RemoteLinkAddress = remote ref.ep.HandlePacket(&r, vv) @@ -559,8 +603,9 @@ func (n *NIC) DeliverNetworkPacket(linkEP LinkEndpoint, remote, _ tcpip.LinkAddr n := r.ref.nic n.mu.RLock() ref, ok := n.endpoints[NetworkEndpointID{dst}] + ok = ok && ref.isValidForOutgoing() && ref.tryIncRef() n.mu.RUnlock() - if ok && ref.tryIncRef() { + if ok { r.RemoteAddress = src // TODO(b/123449044): Update the source NIC as well. ref.ep.HandlePacket(&r, vv) @@ -672,9 +717,33 @@ func (n *NIC) ID() tcpip.NICID { return n.id } +type networkEndpointKind int + +const ( + // A permanent endpoint is created by adding a permanent address (vs. a + // temporary one) to the NIC. Its reference count is biased by 1 to avoid + // removal when no route holds a reference to it. It is removed by explicitly + // removing the permanent address from the NIC. + permanent networkEndpointKind = iota + + // An expired permanent endoint is a permanent endoint that had its address + // removed from the NIC, and it is waiting to be removed once no more routes + // hold a reference to it. This is achieved by decreasing its reference count + // by 1. If its address is re-added before the endpoint is removed, its type + // changes back to permanent and its reference count increases by 1 again. + permanentExpired + + // A temporary endpoint is created for spoofing outgoing packets, or when in + // promiscuous mode and accepting incoming packets that don't match any + // permanent endpoint. Its reference count is not biased by 1 and the + // endpoint is removed immediately when no more route holds a reference to + // it. A temporary endpoint can be promoted to permanent if its address + // is added permanently. + temporary +) + type referencedNetworkEndpoint struct { ilist.Entry - refs int32 ep NetworkEndpoint nic *NIC protocol tcpip.NetworkProtocolNumber @@ -683,11 +752,25 @@ type referencedNetworkEndpoint struct { // protocol. Set to nil otherwise. linkCache LinkAddressCache - // holdsInsertRef is protected by the NIC's mutex. It indicates whether - // the reference count is biased by 1 due to the insertion of the - // endpoint. It is reset to false when RemoveAddress is called on the - // NIC. - holdsInsertRef bool + // refs is counting references held for this endpoint. When refs hits zero it + // triggers the automatic removal of the endpoint from the NIC. + refs int32 + + kind networkEndpointKind +} + +// isValidForOutgoing returns true if the endpoint can be used to send out a +// packet. It requires the endpoint to not be marked expired (i.e., its address +// has been removed), or the NIC to be in spoofing mode. +func (r *referencedNetworkEndpoint) isValidForOutgoing() bool { + return r.kind != permanentExpired || r.nic.spoofing +} + +// isValidForIncoming returns true if the endpoint can accept an incoming +// packet. It requires the endpoint to not be marked expired (i.e., its address +// has been removed), or the NIC to be in promiscuous mode. +func (r *referencedNetworkEndpoint) isValidForIncoming() bool { + return r.kind != permanentExpired || r.nic.promiscuous } // decRef decrements the ref count and cleans up the endpoint once it reaches diff --git a/pkg/tcpip/stack/route.go b/pkg/tcpip/stack/route.go index 391ab4344..e52cdd674 100644 --- a/pkg/tcpip/stack/route.go +++ b/pkg/tcpip/stack/route.go @@ -148,11 +148,15 @@ func (r *Route) RemoveWaker(waker *sleep.Waker) { // IsResolutionRequired returns true if Resolve() must be called to resolve // the link address before the this route can be written to. func (r *Route) IsResolutionRequired() bool { - return r.ref.linkCache != nil && r.RemoteLinkAddress == "" + return r.ref.isValidForOutgoing() && r.ref.linkCache != nil && r.RemoteLinkAddress == "" } // WritePacket writes the packet through the given route. func (r *Route) WritePacket(gso *GSO, hdr buffer.Prependable, payload buffer.VectorisedView, protocol tcpip.TransportProtocolNumber, ttl uint8) *tcpip.Error { + if !r.ref.isValidForOutgoing() { + return tcpip.ErrInvalidEndpointState + } + err := r.ref.ep.WritePacket(r, gso, hdr, payload, protocol, ttl, r.loop) if err != nil { r.Stats().IP.OutgoingPacketErrors.Increment() @@ -166,6 +170,10 @@ func (r *Route) WritePacket(gso *GSO, hdr buffer.Prependable, payload buffer.Vec // WriteHeaderIncludedPacket writes a packet already containing a network // header through the given route. func (r *Route) WriteHeaderIncludedPacket(payload buffer.VectorisedView) *tcpip.Error { + if !r.ref.isValidForOutgoing() { + return tcpip.ErrInvalidEndpointState + } + if err := r.ref.ep.WriteHeaderIncludedPacket(r, payload, r.loop); err != nil { r.Stats().IP.OutgoingPacketErrors.Increment() return err diff --git a/pkg/tcpip/stack/stack_test.go b/pkg/tcpip/stack/stack_test.go index 137c6183e..4debd1eec 100644 --- a/pkg/tcpip/stack/stack_test.go +++ b/pkg/tcpip/stack/stack_test.go @@ -181,6 +181,10 @@ func (f *fakeNetworkProtocol) DefaultPrefixLen() int { return fakeDefaultPrefixLen } +func (f *fakeNetworkProtocol) PacketCount(intfAddr byte) int { + return f.packetCount[int(intfAddr)%len(f.packetCount)] +} + func (*fakeNetworkProtocol) ParseAddresses(v buffer.View) (src, dst tcpip.Address) { return tcpip.Address(v[1:2]), tcpip.Address(v[0:1]) } @@ -289,16 +293,75 @@ func TestNetworkReceive(t *testing.T) { } } -func sendTo(t *testing.T, s *stack.Stack, addr tcpip.Address, payload buffer.View) { +func sendTo(s *stack.Stack, addr tcpip.Address, payload buffer.View) *tcpip.Error { r, err := s.FindRoute(0, "", addr, fakeNetNumber, false /* multicastLoop */) if err != nil { - t.Fatal("FindRoute failed:", err) + return err } defer r.Release() + return send(r, payload) +} +func send(r stack.Route, payload buffer.View) *tcpip.Error { hdr := buffer.NewPrependable(int(r.MaxHeaderLength())) - if err := r.WritePacket(nil /* gso */, hdr, payload.ToVectorisedView(), fakeTransNumber, 123); err != nil { - t.Error("WritePacket failed:", err) + return r.WritePacket(nil /* gso */, hdr, payload.ToVectorisedView(), fakeTransNumber, 123) +} + +func testSendTo(t *testing.T, s *stack.Stack, addr tcpip.Address, linkEP *channel.Endpoint, payload buffer.View) { + t.Helper() + linkEP.Drain() + if err := sendTo(s, addr, payload); err != nil { + t.Error("sendTo failed:", err) + } + if got, want := linkEP.Drain(), 1; got != want { + t.Errorf("sendTo packet count: got = %d, want %d", got, want) + } +} + +func testSend(t *testing.T, r stack.Route, linkEP *channel.Endpoint, payload buffer.View) { + t.Helper() + linkEP.Drain() + if err := send(r, payload); err != nil { + t.Error("send failed:", err) + } + if got, want := linkEP.Drain(), 1; got != want { + t.Errorf("send packet count: got = %d, want %d", got, want) + } +} + +func testFailingSend(t *testing.T, r stack.Route, linkEP *channel.Endpoint, payload buffer.View, wantErr *tcpip.Error) { + t.Helper() + if gotErr := send(r, payload); gotErr != wantErr { + t.Errorf("send failed: got = %s, want = %s ", gotErr, wantErr) + } +} + +func testFailingSendTo(t *testing.T, s *stack.Stack, addr tcpip.Address, linkEP *channel.Endpoint, payload buffer.View, wantErr *tcpip.Error) { + t.Helper() + if gotErr := sendTo(s, addr, payload); gotErr != wantErr { + t.Errorf("sendto failed: got = %s, want = %s ", gotErr, wantErr) + } +} + +func testRecv(t *testing.T, fakeNet *fakeNetworkProtocol, localAddrByte byte, linkEP *channel.Endpoint, buf buffer.View) { + t.Helper() + // testRecvInternal injects one packet, and we expect to receive it. + want := fakeNet.PacketCount(localAddrByte) + 1 + testRecvInternal(t, fakeNet, localAddrByte, linkEP, buf, want) +} + +func testFailingRecv(t *testing.T, fakeNet *fakeNetworkProtocol, localAddrByte byte, linkEP *channel.Endpoint, buf buffer.View) { + t.Helper() + // testRecvInternal injects one packet, and we do NOT expect to receive it. + want := fakeNet.PacketCount(localAddrByte) + testRecvInternal(t, fakeNet, localAddrByte, linkEP, buf, want) +} + +func testRecvInternal(t *testing.T, fakeNet *fakeNetworkProtocol, localAddrByte byte, linkEP *channel.Endpoint, buf buffer.View, want int) { + t.Helper() + linkEP.Inject(fakeNetNumber, buf.ToVectorisedView()) + if got := fakeNet.PacketCount(localAddrByte); got != want { + t.Errorf("receive packet count: got = %d, want %d", got, want) } } @@ -325,10 +388,7 @@ func TestNetworkSend(t *testing.T) { } // Make sure that the link-layer endpoint received the outbound packet. - sendTo(t, s, "\x03", nil) - if c := linkEP.Drain(); c != 1 { - t.Errorf("packetCount = %d, want %d", c, 1) - } + testSendTo(t, s, "\x03", linkEP, nil) } func TestNetworkSendMultiRoute(t *testing.T) { @@ -382,18 +442,10 @@ func TestNetworkSendMultiRoute(t *testing.T) { } // Send a packet to an odd destination. - sendTo(t, s, "\x05", nil) - - if c := linkEP1.Drain(); c != 1 { - t.Errorf("packetCount = %d, want %d", c, 1) - } + testSendTo(t, s, "\x05", linkEP1, nil) // Send a packet to an even destination. - sendTo(t, s, "\x06", nil) - - if c := linkEP2.Drain(); c != 1 { - t.Errorf("packetCount = %d, want %d", c, 1) - } + testSendTo(t, s, "\x06", linkEP2, nil) } func testRoute(t *testing.T, s *stack.Stack, nic tcpip.NICID, srcAddr, dstAddr, expectedSrcAddr tcpip.Address) { @@ -498,6 +550,10 @@ func TestRoutes(t *testing.T) { } func TestAddressRemoval(t *testing.T) { + const localAddrByte byte = 0x01 + localAddr := tcpip.Address([]byte{localAddrByte}) + remoteAddr := tcpip.Address("\x02") + s := stack.New([]string{"fakeNet"}, nil, stack.Options{}) id, linkEP := channel.New(10, defaultMTU, "") @@ -505,51 +561,56 @@ func TestAddressRemoval(t *testing.T) { t.Fatal("CreateNIC failed:", err) } - if err := s.AddAddress(1, fakeNetNumber, "\x01"); err != nil { + if err := s.AddAddress(1, fakeNetNumber, localAddr); err != nil { t.Fatal("AddAddress failed:", err) } + { + subnet, err := tcpip.NewSubnet("\x00", "\x00") + if err != nil { + t.Fatal(err) + } + s.SetRouteTable([]tcpip.Route{{Destination: subnet, Gateway: "\x00", NIC: 1}}) + } fakeNet := s.NetworkProtocolInstance(fakeNetNumber).(*fakeNetworkProtocol) buf := buffer.NewView(30) - // Write a packet, and check that it gets delivered. - fakeNet.packetCount[1] = 0 - buf[0] = 1 - linkEP.Inject(fakeNetNumber, buf.ToVectorisedView()) - if fakeNet.packetCount[1] != 1 { - t.Errorf("packetCount[1] = %d, want %d", fakeNet.packetCount[1], 1) - } + // Send and receive packets, and verify they are received. + buf[0] = localAddrByte + testRecv(t, fakeNet, localAddrByte, linkEP, buf) + testSendTo(t, s, remoteAddr, linkEP, nil) - // Remove the address, then check that packet doesn't get delivered - // anymore. - if err := s.RemoveAddress(1, "\x01"); err != nil { + // Remove the address, then check that send/receive doesn't work anymore. + if err := s.RemoveAddress(1, localAddr); err != nil { t.Fatal("RemoveAddress failed:", err) } - - linkEP.Inject(fakeNetNumber, buf.ToVectorisedView()) - if fakeNet.packetCount[1] != 1 { - t.Errorf("packetCount[1] = %d, want %d", fakeNet.packetCount[1], 1) - } + testFailingRecv(t, fakeNet, localAddrByte, linkEP, buf) + testFailingSendTo(t, s, remoteAddr, linkEP, nil, tcpip.ErrNoRoute) // Check that removing the same address fails. - if err := s.RemoveAddress(1, "\x01"); err != tcpip.ErrBadLocalAddress { + if err := s.RemoveAddress(1, localAddr); err != tcpip.ErrBadLocalAddress { t.Fatalf("RemoveAddress returned unexpected error, got = %v, want = %s", err, tcpip.ErrBadLocalAddress) } } -func TestDelayedRemovalDueToRoute(t *testing.T) { +func TestAddressRemovalWithRouteHeld(t *testing.T) { + const localAddrByte byte = 0x01 + localAddr := tcpip.Address([]byte{localAddrByte}) + remoteAddr := tcpip.Address("\x02") + s := stack.New([]string{"fakeNet"}, nil, stack.Options{}) id, linkEP := channel.New(10, defaultMTU, "") if err := s.CreateNIC(1, id); err != nil { t.Fatal("CreateNIC failed:", err) } + fakeNet := s.NetworkProtocolInstance(fakeNetNumber).(*fakeNetworkProtocol) + buf := buffer.NewView(30) - if err := s.AddAddress(1, fakeNetNumber, "\x01"); err != nil { + if err := s.AddAddress(1, fakeNetNumber, localAddr); err != nil { t.Fatal("AddAddress failed:", err) } - { subnet, err := tcpip.NewSubnet("\x00", "\x00") if err != nil { @@ -558,50 +619,227 @@ func TestDelayedRemovalDueToRoute(t *testing.T) { s.SetRouteTable([]tcpip.Route{{Destination: subnet, Gateway: "\x00", NIC: 1}}) } - fakeNet := s.NetworkProtocolInstance(fakeNetNumber).(*fakeNetworkProtocol) - - buf := buffer.NewView(30) - - // Write a packet, and check that it gets delivered. - fakeNet.packetCount[1] = 0 - buf[0] = 1 - linkEP.Inject(fakeNetNumber, buf.ToVectorisedView()) - if fakeNet.packetCount[1] != 1 { - t.Errorf("packetCount[1] = %d, want %d", fakeNet.packetCount[1], 1) - } - - // Get a route, check that packet is still deliverable. - r, err := s.FindRoute(0, "", "\x02", fakeNetNumber, false /* multicastLoop */) + r, err := s.FindRoute(0, "", remoteAddr, fakeNetNumber, false /* multicastLoop */) if err != nil { t.Fatal("FindRoute failed:", err) } - linkEP.Inject(fakeNetNumber, buf.ToVectorisedView()) - if fakeNet.packetCount[1] != 2 { - t.Errorf("packetCount[1] = %d, want %d", fakeNet.packetCount[1], 2) - } + // Send and receive packets, and verify they are received. + buf[0] = localAddrByte + testRecv(t, fakeNet, localAddrByte, linkEP, buf) + testSend(t, r, linkEP, nil) + testSendTo(t, s, remoteAddr, linkEP, nil) - // Remove the address, then check that packet is still deliverable - // because the route is keeping the address alive. - if err := s.RemoveAddress(1, "\x01"); err != nil { + // Remove the address, then check that send/receive doesn't work anymore. + if err := s.RemoveAddress(1, localAddr); err != nil { t.Fatal("RemoveAddress failed:", err) } - - linkEP.Inject(fakeNetNumber, buf.ToVectorisedView()) - if fakeNet.packetCount[1] != 3 { - t.Errorf("packetCount[1] = %d, want %d", fakeNet.packetCount[1], 3) - } + testFailingRecv(t, fakeNet, localAddrByte, linkEP, buf) + testFailingSend(t, r, linkEP, nil, tcpip.ErrInvalidEndpointState) + testFailingSendTo(t, s, remoteAddr, linkEP, nil, tcpip.ErrNoRoute) // Check that removing the same address fails. - if err := s.RemoveAddress(1, "\x01"); err != tcpip.ErrBadLocalAddress { + if err := s.RemoveAddress(1, localAddr); err != tcpip.ErrBadLocalAddress { t.Fatalf("RemoveAddress returned unexpected error, got = %v, want = %s", err, tcpip.ErrBadLocalAddress) } +} - // Release the route, then check that packet is not deliverable anymore. - r.Release() - linkEP.Inject(fakeNetNumber, buf.ToVectorisedView()) - if fakeNet.packetCount[1] != 3 { - t.Errorf("packetCount[1] = %d, want %d", fakeNet.packetCount[1], 3) +func verifyAddress(t *testing.T, s *stack.Stack, nicid tcpip.NICID, addr tcpip.Address) { + t.Helper() + info, ok := s.NICInfo()[nicid] + if !ok { + t.Fatalf("NICInfo() failed to find nicid=%d", nicid) + } + if len(addr) == 0 { + // No address given, verify that there is no address assigned to the NIC. + for _, a := range info.ProtocolAddresses { + if a.Protocol == fakeNetNumber && a.AddressWithPrefix != (tcpip.AddressWithPrefix{}) { + t.Errorf("verify no-address: got = %s, want = %s", a.AddressWithPrefix, (tcpip.AddressWithPrefix{})) + } + } + return + } + // Address given, verify the address is assigned to the NIC and no other + // address is. + found := false + for _, a := range info.ProtocolAddresses { + if a.Protocol == fakeNetNumber { + if a.AddressWithPrefix.Address == addr { + found = true + } else { + t.Errorf("verify address: got = %s, want = %s", a.AddressWithPrefix.Address, addr) + } + } + } + if !found { + t.Errorf("verify address: couldn't find %s on the NIC", addr) + } +} + +func TestEndpointExpiration(t *testing.T) { + const ( + localAddrByte byte = 0x01 + remoteAddr tcpip.Address = "\x03" + noAddr tcpip.Address = "" + nicid tcpip.NICID = 1 + ) + localAddr := tcpip.Address([]byte{localAddrByte}) + + for _, promiscuous := range []bool{true, false} { + for _, spoofing := range []bool{true, false} { + t.Run(fmt.Sprintf("promiscuous=%t spoofing=%t", promiscuous, spoofing), func(t *testing.T) { + s := stack.New([]string{"fakeNet"}, nil, stack.Options{}) + + id, linkEP := channel.New(10, defaultMTU, "") + if err := s.CreateNIC(nicid, id); err != nil { + t.Fatal("CreateNIC failed:", err) + } + + { + subnet, err := tcpip.NewSubnet("\x00", "\x00") + if err != nil { + t.Fatal(err) + } + s.SetRouteTable([]tcpip.Route{{Destination: subnet, Gateway: "\x00", NIC: 1}}) + } + + fakeNet := s.NetworkProtocolInstance(fakeNetNumber).(*fakeNetworkProtocol) + buf := buffer.NewView(30) + buf[0] = localAddrByte + + if promiscuous { + if err := s.SetPromiscuousMode(nicid, true); err != nil { + t.Fatal("SetPromiscuousMode failed:", err) + } + } + + if spoofing { + if err := s.SetSpoofing(nicid, true); err != nil { + t.Fatal("SetSpoofing failed:", err) + } + } + + // 1. No Address yet, send should only work for spoofing, receive for + // promiscuous mode. + //----------------------- + verifyAddress(t, s, nicid, noAddr) + if promiscuous { + testRecv(t, fakeNet, localAddrByte, linkEP, buf) + } else { + testFailingRecv(t, fakeNet, localAddrByte, linkEP, buf) + } + if spoofing { + // FIXME(b/139841518):Spoofing doesn't work if there is no primary address. + // testSendTo(t, s, remoteAddr, linkEP, nil) + } else { + testFailingSendTo(t, s, remoteAddr, linkEP, nil, tcpip.ErrNoRoute) + } + + // 2. Add Address, everything should work. + //----------------------- + if err := s.AddAddress(nicid, fakeNetNumber, localAddr); err != nil { + t.Fatal("AddAddress failed:", err) + } + verifyAddress(t, s, nicid, localAddr) + testRecv(t, fakeNet, localAddrByte, linkEP, buf) + testSendTo(t, s, remoteAddr, linkEP, nil) + + // 3. Remove the address, send should only work for spoofing, receive + // for promiscuous mode. + //----------------------- + if err := s.RemoveAddress(nicid, localAddr); err != nil { + t.Fatal("RemoveAddress failed:", err) + } + verifyAddress(t, s, nicid, noAddr) + if promiscuous { + testRecv(t, fakeNet, localAddrByte, linkEP, buf) + } else { + testFailingRecv(t, fakeNet, localAddrByte, linkEP, buf) + } + if spoofing { + // FIXME(b/139841518):Spoofing doesn't work if there is no primary address. + // testSendTo(t, s, remoteAddr, linkEP, nil) + } else { + testFailingSendTo(t, s, remoteAddr, linkEP, nil, tcpip.ErrNoRoute) + } + + // 4. Add Address back, everything should work again. + //----------------------- + if err := s.AddAddress(nicid, fakeNetNumber, localAddr); err != nil { + t.Fatal("AddAddress failed:", err) + } + verifyAddress(t, s, nicid, localAddr) + testRecv(t, fakeNet, localAddrByte, linkEP, buf) + testSendTo(t, s, remoteAddr, linkEP, nil) + + // 5. Take a reference to the endpoint by getting a route. Verify that + // we can still send/receive, including sending using the route. + //----------------------- + r, err := s.FindRoute(0, "", remoteAddr, fakeNetNumber, false /* multicastLoop */) + if err != nil { + t.Fatal("FindRoute failed:", err) + } + testRecv(t, fakeNet, localAddrByte, linkEP, buf) + testSendTo(t, s, remoteAddr, linkEP, nil) + testSend(t, r, linkEP, nil) + + // 6. Remove the address. Send should only work for spoofing, receive + // for promiscuous mode. + //----------------------- + if err := s.RemoveAddress(nicid, localAddr); err != nil { + t.Fatal("RemoveAddress failed:", err) + } + verifyAddress(t, s, nicid, noAddr) + if promiscuous { + testRecv(t, fakeNet, localAddrByte, linkEP, buf) + } else { + testFailingRecv(t, fakeNet, localAddrByte, linkEP, buf) + } + if spoofing { + testSend(t, r, linkEP, nil) + testSendTo(t, s, remoteAddr, linkEP, nil) + } else { + testFailingSend(t, r, linkEP, nil, tcpip.ErrInvalidEndpointState) + testFailingSendTo(t, s, remoteAddr, linkEP, nil, tcpip.ErrNoRoute) + } + + // 7. Add Address back, everything should work again. + //----------------------- + if err := s.AddAddress(nicid, fakeNetNumber, localAddr); err != nil { + t.Fatal("AddAddress failed:", err) + } + verifyAddress(t, s, nicid, localAddr) + testRecv(t, fakeNet, localAddrByte, linkEP, buf) + testSendTo(t, s, remoteAddr, linkEP, nil) + testSend(t, r, linkEP, nil) + + // 8. Remove the route, sendTo/recv should still work. + //----------------------- + r.Release() + verifyAddress(t, s, nicid, localAddr) + testRecv(t, fakeNet, localAddrByte, linkEP, buf) + testSendTo(t, s, remoteAddr, linkEP, nil) + + // 9. Remove the address. Send should only work for spoofing, receive + // for promiscuous mode. + //----------------------- + if err := s.RemoveAddress(nicid, localAddr); err != nil { + t.Fatal("RemoveAddress failed:", err) + } + verifyAddress(t, s, nicid, noAddr) + if promiscuous { + testRecv(t, fakeNet, localAddrByte, linkEP, buf) + } else { + testFailingRecv(t, fakeNet, localAddrByte, linkEP, buf) + } + if spoofing { + // FIXME(b/139841518):Spoofing doesn't work if there is no primary address. + // testSendTo(t, s, remoteAddr, linkEP, nil) + } else { + testFailingSendTo(t, s, remoteAddr, linkEP, nil, tcpip.ErrNoRoute) + } + }) + } } } @@ -627,22 +865,15 @@ func TestPromiscuousMode(t *testing.T) { // Write a packet, and check that it doesn't get delivered as we don't // have a matching endpoint. - fakeNet.packetCount[1] = 0 - buf[0] = 1 - linkEP.Inject(fakeNetNumber, buf.ToVectorisedView()) - if fakeNet.packetCount[1] != 0 { - t.Errorf("packetCount[1] = %d, want %d", fakeNet.packetCount[1], 0) - } + const localAddrByte byte = 0x01 + buf[0] = localAddrByte + testFailingRecv(t, fakeNet, localAddrByte, linkEP, buf) // Set promiscuous mode, then check that packet is delivered. if err := s.SetPromiscuousMode(1, true); err != nil { t.Fatal("SetPromiscuousMode failed:", err) } - - linkEP.Inject(fakeNetNumber, buf.ToVectorisedView()) - if fakeNet.packetCount[1] != 1 { - t.Errorf("packetCount[1] = %d, want %d", fakeNet.packetCount[1], 1) - } + testRecv(t, fakeNet, localAddrByte, linkEP, buf) // Check that we can't get a route as there is no local address. _, err := s.FindRoute(0, "", "\x02", fakeNetNumber, false /* multicastLoop */) @@ -655,25 +886,22 @@ func TestPromiscuousMode(t *testing.T) { if err := s.SetPromiscuousMode(1, false); err != nil { t.Fatal("SetPromiscuousMode failed:", err) } - - linkEP.Inject(fakeNetNumber, buf.ToVectorisedView()) - if fakeNet.packetCount[1] != 1 { - t.Errorf("packetCount[1] = %d, want %d", fakeNet.packetCount[1], 1) - } + testFailingRecv(t, fakeNet, localAddrByte, linkEP, buf) } -func TestAddressSpoofing(t *testing.T) { - srcAddr := tcpip.Address("\x01") - dstAddr := tcpip.Address("\x02") +func TestSpoofingWithAddress(t *testing.T) { + localAddr := tcpip.Address("\x01") + nonExistentLocalAddr := tcpip.Address("\x02") + dstAddr := tcpip.Address("\x03") s := stack.New([]string{"fakeNet"}, nil, stack.Options{}) - id, _ := channel.New(10, defaultMTU, "") + id, linkEP := channel.New(10, defaultMTU, "") if err := s.CreateNIC(1, id); err != nil { t.Fatal("CreateNIC failed:", err) } - if err := s.AddAddress(1, fakeNetNumber, dstAddr); err != nil { + if err := s.AddAddress(1, fakeNetNumber, localAddr); err != nil { t.Fatal("AddAddress failed:", err) } @@ -687,7 +915,7 @@ func TestAddressSpoofing(t *testing.T) { // With address spoofing disabled, FindRoute does not permit an address // that was not added to the NIC to be used as the source. - r, err := s.FindRoute(0, srcAddr, dstAddr, fakeNetNumber, false /* multicastLoop */) + r, err := s.FindRoute(0, nonExistentLocalAddr, dstAddr, fakeNetNumber, false /* multicastLoop */) if err == nil { t.Errorf("FindRoute succeeded with route %+v when it should have failed", r) } @@ -697,16 +925,81 @@ func TestAddressSpoofing(t *testing.T) { if err := s.SetSpoofing(1, true); err != nil { t.Fatal("SetSpoofing failed:", err) } - r, err = s.FindRoute(0, srcAddr, dstAddr, fakeNetNumber, false /* multicastLoop */) + r, err = s.FindRoute(0, nonExistentLocalAddr, dstAddr, fakeNetNumber, false /* multicastLoop */) + if err != nil { + t.Fatal("FindRoute failed:", err) + } + if r.LocalAddress != nonExistentLocalAddr { + t.Errorf("Route has wrong local address: got %v, wanted %v", r.LocalAddress, nonExistentLocalAddr) + } + if r.RemoteAddress != dstAddr { + t.Errorf("Route has wrong remote address: got %v, wanted %v", r.RemoteAddress, dstAddr) + } + // Sending a packet works. + testSendTo(t, s, dstAddr, linkEP, nil) + testSend(t, r, linkEP, nil) + + // FindRoute should also work with a local address that exists on the NIC. + r, err = s.FindRoute(0, localAddr, dstAddr, fakeNetNumber, false /* multicastLoop */) if err != nil { t.Fatal("FindRoute failed:", err) } - if r.LocalAddress != srcAddr { - t.Errorf("Route has wrong local address: got %v, wanted %v", r.LocalAddress, srcAddr) + if r.LocalAddress != localAddr { + t.Errorf("Route has wrong local address: got %v, wanted %v", r.LocalAddress, nonExistentLocalAddr) } if r.RemoteAddress != dstAddr { t.Errorf("Route has wrong remote address: got %v, wanted %v", r.RemoteAddress, dstAddr) } + // Sending a packet using the route works. + testSend(t, r, linkEP, nil) +} + +func TestSpoofingNoAddress(t *testing.T) { + nonExistentLocalAddr := tcpip.Address("\x01") + dstAddr := tcpip.Address("\x02") + + s := stack.New([]string{"fakeNet"}, nil, stack.Options{}) + + id, linkEP := channel.New(10, defaultMTU, "") + if err := s.CreateNIC(1, id); err != nil { + t.Fatal("CreateNIC failed:", err) + } + + { + subnet, err := tcpip.NewSubnet("\x00", "\x00") + if err != nil { + t.Fatal(err) + } + s.SetRouteTable([]tcpip.Route{{Destination: subnet, Gateway: "\x00", NIC: 1}}) + } + + // With address spoofing disabled, FindRoute does not permit an address + // that was not added to the NIC to be used as the source. + r, err := s.FindRoute(0, nonExistentLocalAddr, dstAddr, fakeNetNumber, false /* multicastLoop */) + if err == nil { + t.Errorf("FindRoute succeeded with route %+v when it should have failed", r) + } + // Sending a packet fails. + testFailingSendTo(t, s, dstAddr, linkEP, nil, tcpip.ErrNoRoute) + + // With address spoofing enabled, FindRoute permits any address to be used + // as the source. + if err := s.SetSpoofing(1, true); err != nil { + t.Fatal("SetSpoofing failed:", err) + } + r, err = s.FindRoute(0, nonExistentLocalAddr, dstAddr, fakeNetNumber, false /* multicastLoop */) + if err != nil { + t.Fatal("FindRoute failed:", err) + } + if r.LocalAddress != nonExistentLocalAddr { + t.Errorf("Route has wrong local address: got %v, wanted %v", r.LocalAddress, nonExistentLocalAddr) + } + if r.RemoteAddress != dstAddr { + t.Errorf("Route has wrong remote address: got %v, wanted %v", r.RemoteAddress, dstAddr) + } + // Sending a packet works. + // FIXME(b/139841518):Spoofing doesn't work if there is no primary address. + // testSendTo(t, s, remoteAddr, linkEP, nil) } func TestBroadcastNeedsNoRoute(t *testing.T) { @@ -856,8 +1149,8 @@ func TestSubnetAcceptsMatchingPacket(t *testing.T) { buf := buffer.NewView(30) - buf[0] = 1 - fakeNet.packetCount[1] = 0 + const localAddrByte byte = 0x01 + buf[0] = localAddrByte subnet, err := tcpip.NewSubnet(tcpip.Address("\x00"), tcpip.AddressMask("\xF0")) if err != nil { t.Fatal("NewSubnet failed:", err) @@ -866,10 +1159,7 @@ func TestSubnetAcceptsMatchingPacket(t *testing.T) { t.Fatal("AddSubnet failed:", err) } - linkEP.Inject(fakeNetNumber, buf.ToVectorisedView()) - if fakeNet.packetCount[1] != 1 { - t.Errorf("packetCount[1] = %d, want %d", fakeNet.packetCount[1], 1) - } + testRecv(t, fakeNet, localAddrByte, linkEP, buf) } // Set the subnet, then check that CheckLocalAddress returns the correct NIC. @@ -939,8 +1229,8 @@ func TestSubnetRejectsNonmatchingPacket(t *testing.T) { buf := buffer.NewView(30) - buf[0] = 1 - fakeNet.packetCount[1] = 0 + const localAddrByte byte = 0x01 + buf[0] = localAddrByte subnet, err := tcpip.NewSubnet(tcpip.Address("\x10"), tcpip.AddressMask("\xF0")) if err != nil { t.Fatal("NewSubnet failed:", err) @@ -948,10 +1238,7 @@ func TestSubnetRejectsNonmatchingPacket(t *testing.T) { if err := s.AddSubnet(1, fakeNetNumber, subnet); err != nil { t.Fatal("AddSubnet failed:", err) } - linkEP.Inject(fakeNetNumber, buf.ToVectorisedView()) - if fakeNet.packetCount[1] != 0 { - t.Errorf("packetCount[1] = %d, want %d", fakeNet.packetCount[1], 0) - } + testFailingRecv(t, fakeNet, localAddrByte, linkEP, buf) } func TestNetworkOptions(t *testing.T) { @@ -1305,7 +1592,7 @@ func TestNICStats(t *testing.T) { s := stack.New([]string{"fakeNet"}, nil, stack.Options{}) id1, linkEP1 := channel.New(10, defaultMTU, "") if err := s.CreateNIC(1, id1); err != nil { - t.Fatal("CreateNIC failed:", err) + t.Fatal("CreateNIC failed: ", err) } if err := s.AddAddress(1, fakeNetNumber, "\x01"); err != nil { t.Fatal("AddAddress failed:", err) @@ -1332,7 +1619,9 @@ func TestNICStats(t *testing.T) { payload := buffer.NewView(10) // Write a packet out via the address for NIC 1 - sendTo(t, s, "\x01", payload) + if err := sendTo(s, "\x01", payload); err != nil { + t.Fatal("sendTo failed: ", err) + } want := uint64(linkEP1.Drain()) if got := s.NICInfo()[1].Stats.Tx.Packets.Value(); got != want { t.Errorf("got Tx.Packets.Value() = %d, linkEP1.Drain() = %d", got, want) |