From 67b615b86f2aa1d4ded3dcf2eb8aca4e7fec57a0 Mon Sep 17 00:00:00 2001 From: gVisor bot Date: Thu, 20 Feb 2020 14:31:39 -0800 Subject: Support disabling a NIC - Disabled NICs will have their associated NDP state cleared. - Disabled NICs will not accept incoming packets. - Writes through a Route with a disabled NIC will return an invalid endpoint state error. - stack.Stack.FindRoute will not return a route with a disabled NIC. - NIC's Running flag will report the NIC's enabled status. Tests: - stack_test.TestDisableUnknownNIC - stack_test.TestDisabledNICsNICInfoAndCheckNIC - stack_test.TestRoutesWithDisabledNIC - stack_test.TestRouteWritePacketWithDisabledNIC - stack_test.TestStopStartSolicitingRouters - stack_test.TestCleanupNDPState - stack_test.TestAddRemoveIPv4BroadcastAddressOnNICEnableDisable - stack_test.TestJoinLeaveAllNodesMulticastOnNICEnableDisable PiperOrigin-RevId: 296298588 --- pkg/tcpip/stack/ndp.go | 23 +- pkg/tcpip/stack/ndp_test.go | 822 ++++++++++++++++++++++++------------------ pkg/tcpip/stack/nic.go | 110 +++++- pkg/tcpip/stack/stack.go | 45 ++- pkg/tcpip/stack/stack_test.go | 377 ++++++++++++++++++- 5 files changed, 998 insertions(+), 379 deletions(-) (limited to 'pkg') diff --git a/pkg/tcpip/stack/ndp.go b/pkg/tcpip/stack/ndp.go index 045409bda..19bd05aa3 100644 --- a/pkg/tcpip/stack/ndp.go +++ b/pkg/tcpip/stack/ndp.go @@ -1148,22 +1148,27 @@ func (ndp *ndpState) cleanupAutoGenAddrResourcesAndNotify(addr tcpip.Address) bo return true } -// cleanupHostOnlyState cleans up any state that is only useful for hosts. +// cleanupState cleans up ndp's state. // -// cleanupHostOnlyState MUST be called when ndp's NIC is transitioning from a -// host to a router. This function will invalidate all discovered on-link -// prefixes, discovered routers, and auto-generated addresses as routers do not -// normally process Router Advertisements to discover default routers and -// on-link prefixes, and auto-generate addresses via SLAAC. +// If hostOnly is true, then only host-specific state will be cleaned up. +// +// cleanupState MUST be called with hostOnly set to true when ndp's NIC is +// transitioning from a host to a router. This function will invalidate all +// discovered on-link prefixes, discovered routers, and auto-generated +// addresses. +// +// If hostOnly is true, then the link-local auto-generated address will not be +// invalidated as routers are also expected to generate a link-local address. // // The NIC that ndp belongs to MUST be locked. -func (ndp *ndpState) cleanupHostOnlyState() { +func (ndp *ndpState) cleanupState(hostOnly bool) { linkLocalSubnet := header.IPv6LinkLocalPrefix.Subnet() linkLocalAddrs := 0 for addr := range ndp.autoGenAddresses { // RFC 4862 section 5 states that routers are also expected to generate a - // link-local address so we do not invalidate them. - if linkLocalSubnet.Contains(addr) { + // link-local address so we do not invalidate them if we are cleaning up + // host-only state. + if hostOnly && linkLocalSubnet.Contains(addr) { linkLocalAddrs++ continue } diff --git a/pkg/tcpip/stack/ndp_test.go b/pkg/tcpip/stack/ndp_test.go index 1f6f77439..f7b75b74e 100644 --- a/pkg/tcpip/stack/ndp_test.go +++ b/pkg/tcpip/stack/ndp_test.go @@ -592,70 +592,94 @@ func TestDADFail(t *testing.T) { } } -// TestDADStop tests to make sure that the DAD process stops when an address is -// removed. func TestDADStop(t *testing.T) { const nicID = 1 - ndpDisp := ndpDispatcher{ - dadC: make(chan ndpDADEvent, 1), - } - ndpConfigs := stack.NDPConfigurations{ - RetransmitTimer: time.Second, - DupAddrDetectTransmits: 2, - } - opts := stack.Options{ - NetworkProtocols: []stack.NetworkProtocol{ipv6.NewProtocol()}, - NDPDisp: &ndpDisp, - NDPConfigs: ndpConfigs, - } + tests := []struct { + name string + stopFn func(t *testing.T, s *stack.Stack) + }{ + // Tests to make sure that DAD stops when an address is removed. + { + name: "Remove address", + stopFn: func(t *testing.T, s *stack.Stack) { + if err := s.RemoveAddress(nicID, addr1); err != nil { + t.Fatalf("RemoveAddress(%d, %s): %s", nicID, addr1, err) + } + }, + }, - e := channel.New(0, 1280, linkAddr1) - s := stack.New(opts) - if err := s.CreateNIC(nicID, e); err != nil { - t.Fatalf("CreateNIC(%d, _) = %s", nicID, err) + // Tests to make sure that DAD stops when the NIC is disabled. + { + name: "Disable NIC", + stopFn: func(t *testing.T, s *stack.Stack) { + if err := s.DisableNIC(nicID); err != nil { + t.Fatalf("DisableNIC(%d): %s", nicID, err) + } + }, + }, } - if err := s.AddAddress(nicID, header.IPv6ProtocolNumber, addr1); err != nil { - t.Fatalf("AddAddress(%d, %d, %s) = %s", nicID, header.IPv6ProtocolNumber, addr1, err) - } + for _, test := range tests { + t.Run(test.name, func(t *testing.T) { + ndpDisp := ndpDispatcher{ + dadC: make(chan ndpDADEvent, 1), + } + ndpConfigs := stack.NDPConfigurations{ + RetransmitTimer: time.Second, + DupAddrDetectTransmits: 2, + } + opts := stack.Options{ + NetworkProtocols: []stack.NetworkProtocol{ipv6.NewProtocol()}, + NDPDisp: &ndpDisp, + NDPConfigs: ndpConfigs, + } - // Address should not be considered bound to the NIC yet (DAD ongoing). - addr, err := s.GetMainNICAddress(nicID, header.IPv6ProtocolNumber) - if err != nil { - t.Fatalf("got stack.GetMainNICAddress(%d, %d) = (_, %v), want = (_, nil)", nicID, header.IPv6ProtocolNumber, err) - } - if want := (tcpip.AddressWithPrefix{}); addr != want { - t.Fatalf("got stack.GetMainNICAddress(%d, %d) = (%s, nil), want = (%s, nil)", nicID, header.IPv6ProtocolNumber, addr, want) - } + e := channel.New(0, 1280, linkAddr1) + s := stack.New(opts) + if err := s.CreateNIC(nicID, e); err != nil { + t.Fatalf("CreateNIC(%d, _): %s", nicID, err) + } - // Remove the address. This should stop DAD. - if err := s.RemoveAddress(nicID, addr1); err != nil { - t.Fatalf("RemoveAddress(%d, %s) = %s", nicID, addr1, err) - } + if err := s.AddAddress(nicID, header.IPv6ProtocolNumber, addr1); err != nil { + t.Fatalf("AddAddress(%d, %d, %s): %s", nicID, header.IPv6ProtocolNumber, addr1, err) + } - // Wait for DAD to fail (since the address was removed during DAD). - select { - case <-time.After(time.Duration(ndpConfigs.DupAddrDetectTransmits)*ndpConfigs.RetransmitTimer + time.Second): - // If we don't get a failure event after the expected resolution - // time + extra 1s buffer, something is wrong. - t.Fatal("timed out waiting for DAD failure") - case e := <-ndpDisp.dadC: - if diff := checkDADEvent(e, nicID, addr1, false, nil); diff != "" { - t.Errorf("dad event mismatch (-want +got):\n%s", diff) - } - } - addr, err = s.GetMainNICAddress(nicID, header.IPv6ProtocolNumber) - if err != nil { - t.Fatalf("got stack.GetMainNICAddress(%d, %d) = (_, %v), want = (_, nil)", nicID, header.IPv6ProtocolNumber, err) - } - if want := (tcpip.AddressWithPrefix{}); addr != want { - t.Fatalf("got stack.GetMainNICAddress(%d, %d) = (%s, nil), want = (%s, nil)", nicID, header.IPv6ProtocolNumber, addr, want) - } + // Address should not be considered bound to the NIC yet (DAD ongoing). + addr, err := s.GetMainNICAddress(nicID, header.IPv6ProtocolNumber) + if err != nil { + t.Fatalf("got stack.GetMainNICAddress(%d, %d) = (_, %v), want = (_, nil)", nicID, header.IPv6ProtocolNumber, err) + } + if want := (tcpip.AddressWithPrefix{}); addr != want { + t.Fatalf("got stack.GetMainNICAddress(%d, %d) = (%s, nil), want = (%s, nil)", nicID, header.IPv6ProtocolNumber, addr, want) + } + + test.stopFn(t, s) + + // Wait for DAD to fail (since the address was removed during DAD). + select { + case <-time.After(time.Duration(ndpConfigs.DupAddrDetectTransmits)*ndpConfigs.RetransmitTimer + time.Second): + // If we don't get a failure event after the expected resolution + // time + extra 1s buffer, something is wrong. + t.Fatal("timed out waiting for DAD failure") + case e := <-ndpDisp.dadC: + if diff := checkDADEvent(e, nicID, addr1, false, nil); diff != "" { + t.Errorf("dad event mismatch (-want +got):\n%s", diff) + } + } + addr, err = s.GetMainNICAddress(nicID, header.IPv6ProtocolNumber) + if err != nil { + t.Fatalf("got stack.GetMainNICAddress(%d, %d) = (_, %v), want = (_, nil)", nicID, header.IPv6ProtocolNumber, err) + } + if want := (tcpip.AddressWithPrefix{}); addr != want { + t.Errorf("got stack.GetMainNICAddress(%d, %d) = (%s, nil), want = (%s, nil)", nicID, header.IPv6ProtocolNumber, addr, want) + } - // Should not have sent more than 1 NS message. - if got := s.Stats().ICMP.V6PacketsSent.NeighborSolicit.Value(); got > 1 { - t.Fatalf("got NeighborSolicit = %d, want <= 1", got) + // Should not have sent more than 1 NS message. + if got := s.Stats().ICMP.V6PacketsSent.NeighborSolicit.Value(); got > 1 { + t.Errorf("got NeighborSolicit = %d, want <= 1", got) + } + }) } } @@ -2886,17 +2910,16 @@ func TestNDPRecursiveDNSServerDispatch(t *testing.T) { } } -// TestCleanupHostOnlyStateOnBecomingRouter tests that all discovered routers -// and prefixes, and non-linklocal auto-generated addresses are invalidated when -// a NIC becomes a router. -func TestCleanupHostOnlyStateOnBecomingRouter(t *testing.T) { +// TestCleanupNDPState tests that all discovered routers and prefixes, and +// auto-generated addresses are invalidated when a NIC becomes a router. +func TestCleanupNDPState(t *testing.T) { t.Parallel() const ( - lifetimeSeconds = 5 - maxEvents = 4 - nicID1 = 1 - nicID2 = 2 + lifetimeSeconds = 5 + maxRouterAndPrefixEvents = 4 + nicID1 = 1 + nicID2 = 2 ) prefix1, subnet1, e1Addr1 := prefixSubnetAddr(0, linkAddr1) @@ -2912,254 +2935,308 @@ func TestCleanupHostOnlyStateOnBecomingRouter(t *testing.T) { PrefixLen: 64, } - ndpDisp := ndpDispatcher{ - routerC: make(chan ndpRouterEvent, maxEvents), - rememberRouter: true, - prefixC: make(chan ndpPrefixEvent, maxEvents), - rememberPrefix: true, - autoGenAddrC: make(chan ndpAutoGenAddrEvent, maxEvents), - } - s := stack.New(stack.Options{ - NetworkProtocols: []stack.NetworkProtocol{ipv6.NewProtocol()}, - AutoGenIPv6LinkLocal: true, - NDPConfigs: stack.NDPConfigurations{ - HandleRAs: true, - DiscoverDefaultRouters: true, - DiscoverOnLinkPrefixes: true, - AutoGenGlobalAddresses: true, + tests := []struct { + name string + cleanupFn func(t *testing.T, s *stack.Stack) + keepAutoGenLinkLocal bool + maxAutoGenAddrEvents int + }{ + // A NIC should still keep its auto-generated link-local address when + // becoming a router. + { + name: "Forwarding Enable", + cleanupFn: func(t *testing.T, s *stack.Stack) { + t.Helper() + s.SetForwarding(true) + }, + keepAutoGenLinkLocal: true, + maxAutoGenAddrEvents: 4, }, - NDPDisp: &ndpDisp, - }) - expectRouterEvent := func() (bool, ndpRouterEvent) { - select { - case e := <-ndpDisp.routerC: - return true, e - default: - } + // A NIC should cleanup all NDP state when it is disabled. + { + name: "NIC Disable", + cleanupFn: func(t *testing.T, s *stack.Stack) { + t.Helper() - return false, ndpRouterEvent{} + if err := s.DisableNIC(nicID1); err != nil { + t.Fatalf("s.DisableNIC(%d): %s", nicID1, err) + } + if err := s.DisableNIC(nicID2); err != nil { + t.Fatalf("s.DisableNIC(%d): %s", nicID2, err) + } + }, + keepAutoGenLinkLocal: false, + maxAutoGenAddrEvents: 6, + }, } - expectPrefixEvent := func() (bool, ndpPrefixEvent) { - select { - case e := <-ndpDisp.prefixC: - return true, e - default: - } + for _, test := range tests { + t.Run(test.name, func(t *testing.T) { + ndpDisp := ndpDispatcher{ + routerC: make(chan ndpRouterEvent, maxRouterAndPrefixEvents), + rememberRouter: true, + prefixC: make(chan ndpPrefixEvent, maxRouterAndPrefixEvents), + rememberPrefix: true, + autoGenAddrC: make(chan ndpAutoGenAddrEvent, test.maxAutoGenAddrEvents), + } + s := stack.New(stack.Options{ + NetworkProtocols: []stack.NetworkProtocol{ipv6.NewProtocol()}, + AutoGenIPv6LinkLocal: true, + NDPConfigs: stack.NDPConfigurations{ + HandleRAs: true, + DiscoverDefaultRouters: true, + DiscoverOnLinkPrefixes: true, + AutoGenGlobalAddresses: true, + }, + NDPDisp: &ndpDisp, + }) - return false, ndpPrefixEvent{} - } + expectRouterEvent := func() (bool, ndpRouterEvent) { + select { + case e := <-ndpDisp.routerC: + return true, e + default: + } - expectAutoGenAddrEvent := func() (bool, ndpAutoGenAddrEvent) { - select { - case e := <-ndpDisp.autoGenAddrC: - return true, e - default: - } + return false, ndpRouterEvent{} + } - return false, ndpAutoGenAddrEvent{} - } + expectPrefixEvent := func() (bool, ndpPrefixEvent) { + select { + case e := <-ndpDisp.prefixC: + return true, e + default: + } - e1 := channel.New(0, 1280, linkAddr1) - if err := s.CreateNIC(nicID1, e1); err != nil { - t.Fatalf("CreateNIC(%d, _) = %s", nicID1, err) - } - // We have other tests that make sure we receive the *correct* events - // on normal discovery of routers/prefixes, and auto-generated - // addresses. Here we just make sure we get an event and let other tests - // handle the correctness check. - expectAutoGenAddrEvent() + return false, ndpPrefixEvent{} + } - e2 := channel.New(0, 1280, linkAddr2) - if err := s.CreateNIC(nicID2, e2); err != nil { - t.Fatalf("CreateNIC(%d, _) = %s", nicID2, err) - } - expectAutoGenAddrEvent() + expectAutoGenAddrEvent := func() (bool, ndpAutoGenAddrEvent) { + select { + case e := <-ndpDisp.autoGenAddrC: + return true, e + default: + } - // Receive RAs on NIC(1) and NIC(2) from default routers (llAddr3 and - // llAddr4) w/ PI (for prefix1 in RA from llAddr3 and prefix2 in RA from - // llAddr4) to discover multiple routers and prefixes, and auto-gen - // multiple addresses. + return false, ndpAutoGenAddrEvent{} + } - e1.InjectInbound(header.IPv6ProtocolNumber, raBufWithPI(llAddr3, lifetimeSeconds, prefix1, true, true, lifetimeSeconds, lifetimeSeconds)) - if ok, _ := expectRouterEvent(); !ok { - t.Errorf("expected router event for %s on NIC(%d)", llAddr3, nicID1) - } - if ok, _ := expectPrefixEvent(); !ok { - t.Errorf("expected prefix event for %s on NIC(%d)", prefix1, nicID1) - } - if ok, _ := expectAutoGenAddrEvent(); !ok { - t.Errorf("expected auto-gen addr event for %s on NIC(%d)", e1Addr1, nicID1) - } + e1 := channel.New(0, 1280, linkAddr1) + if err := s.CreateNIC(nicID1, e1); err != nil { + t.Fatalf("CreateNIC(%d, _) = %s", nicID1, err) + } + // We have other tests that make sure we receive the *correct* events + // on normal discovery of routers/prefixes, and auto-generated + // addresses. Here we just make sure we get an event and let other tests + // handle the correctness check. + expectAutoGenAddrEvent() - e1.InjectInbound(header.IPv6ProtocolNumber, raBufWithPI(llAddr4, lifetimeSeconds, prefix2, true, true, lifetimeSeconds, lifetimeSeconds)) - if ok, _ := expectRouterEvent(); !ok { - t.Errorf("expected router event for %s on NIC(%d)", llAddr4, nicID1) - } - if ok, _ := expectPrefixEvent(); !ok { - t.Errorf("expected prefix event for %s on NIC(%d)", prefix2, nicID1) - } - if ok, _ := expectAutoGenAddrEvent(); !ok { - t.Errorf("expected auto-gen addr event for %s on NIC(%d)", e1Addr2, nicID1) - } + e2 := channel.New(0, 1280, linkAddr2) + if err := s.CreateNIC(nicID2, e2); err != nil { + t.Fatalf("CreateNIC(%d, _) = %s", nicID2, err) + } + expectAutoGenAddrEvent() - e2.InjectInbound(header.IPv6ProtocolNumber, raBufWithPI(llAddr3, lifetimeSeconds, prefix1, true, true, lifetimeSeconds, lifetimeSeconds)) - if ok, _ := expectRouterEvent(); !ok { - t.Errorf("expected router event for %s on NIC(%d)", llAddr3, nicID2) - } - if ok, _ := expectPrefixEvent(); !ok { - t.Errorf("expected prefix event for %s on NIC(%d)", prefix1, nicID2) - } - if ok, _ := expectAutoGenAddrEvent(); !ok { - t.Errorf("expected auto-gen addr event for %s on NIC(%d)", e1Addr2, nicID2) - } + // Receive RAs on NIC(1) and NIC(2) from default routers (llAddr3 and + // llAddr4) w/ PI (for prefix1 in RA from llAddr3 and prefix2 in RA from + // llAddr4) to discover multiple routers and prefixes, and auto-gen + // multiple addresses. - e2.InjectInbound(header.IPv6ProtocolNumber, raBufWithPI(llAddr4, lifetimeSeconds, prefix2, true, true, lifetimeSeconds, lifetimeSeconds)) - if ok, _ := expectRouterEvent(); !ok { - t.Errorf("expected router event for %s on NIC(%d)", llAddr4, nicID2) - } - if ok, _ := expectPrefixEvent(); !ok { - t.Errorf("expected prefix event for %s on NIC(%d)", prefix2, nicID2) - } - if ok, _ := expectAutoGenAddrEvent(); !ok { - t.Errorf("expected auto-gen addr event for %s on NIC(%d)", e2Addr2, nicID2) - } + e1.InjectInbound(header.IPv6ProtocolNumber, raBufWithPI(llAddr3, lifetimeSeconds, prefix1, true, true, lifetimeSeconds, lifetimeSeconds)) + if ok, _ := expectRouterEvent(); !ok { + t.Errorf("expected router event for %s on NIC(%d)", llAddr3, nicID1) + } + if ok, _ := expectPrefixEvent(); !ok { + t.Errorf("expected prefix event for %s on NIC(%d)", prefix1, nicID1) + } + if ok, _ := expectAutoGenAddrEvent(); !ok { + t.Errorf("expected auto-gen addr event for %s on NIC(%d)", e1Addr1, nicID1) + } - // We should have the auto-generated addresses added. - nicinfo := s.NICInfo() - nic1Addrs := nicinfo[nicID1].ProtocolAddresses - nic2Addrs := nicinfo[nicID2].ProtocolAddresses - if !containsV6Addr(nic1Addrs, llAddrWithPrefix1) { - t.Errorf("missing %s from the list of addresses for NIC(%d): %+v", llAddrWithPrefix1, nicID1, nic1Addrs) - } - if !containsV6Addr(nic1Addrs, e1Addr1) { - t.Errorf("missing %s from the list of addresses for NIC(%d): %+v", e1Addr1, nicID1, nic1Addrs) - } - if !containsV6Addr(nic1Addrs, e1Addr2) { - t.Errorf("missing %s from the list of addresses for NIC(%d): %+v", e1Addr2, nicID1, nic1Addrs) - } - if !containsV6Addr(nic2Addrs, llAddrWithPrefix2) { - t.Errorf("missing %s from the list of addresses for NIC(%d): %+v", llAddrWithPrefix2, nicID2, nic2Addrs) - } - if !containsV6Addr(nic2Addrs, e2Addr1) { - t.Errorf("missing %s from the list of addresses for NIC(%d): %+v", e2Addr1, nicID2, nic2Addrs) - } - if !containsV6Addr(nic2Addrs, e2Addr2) { - t.Errorf("missing %s from the list of addresses for NIC(%d): %+v", e2Addr2, nicID2, nic2Addrs) - } + e1.InjectInbound(header.IPv6ProtocolNumber, raBufWithPI(llAddr4, lifetimeSeconds, prefix2, true, true, lifetimeSeconds, lifetimeSeconds)) + if ok, _ := expectRouterEvent(); !ok { + t.Errorf("expected router event for %s on NIC(%d)", llAddr4, nicID1) + } + if ok, _ := expectPrefixEvent(); !ok { + t.Errorf("expected prefix event for %s on NIC(%d)", prefix2, nicID1) + } + if ok, _ := expectAutoGenAddrEvent(); !ok { + t.Errorf("expected auto-gen addr event for %s on NIC(%d)", e1Addr2, nicID1) + } - // We can't proceed any further if we already failed the test (missing - // some discovery/auto-generated address events or addresses). - if t.Failed() { - t.FailNow() - } + e2.InjectInbound(header.IPv6ProtocolNumber, raBufWithPI(llAddr3, lifetimeSeconds, prefix1, true, true, lifetimeSeconds, lifetimeSeconds)) + if ok, _ := expectRouterEvent(); !ok { + t.Errorf("expected router event for %s on NIC(%d)", llAddr3, nicID2) + } + if ok, _ := expectPrefixEvent(); !ok { + t.Errorf("expected prefix event for %s on NIC(%d)", prefix1, nicID2) + } + if ok, _ := expectAutoGenAddrEvent(); !ok { + t.Errorf("expected auto-gen addr event for %s on NIC(%d)", e1Addr2, nicID2) + } - s.SetForwarding(true) + e2.InjectInbound(header.IPv6ProtocolNumber, raBufWithPI(llAddr4, lifetimeSeconds, prefix2, true, true, lifetimeSeconds, lifetimeSeconds)) + if ok, _ := expectRouterEvent(); !ok { + t.Errorf("expected router event for %s on NIC(%d)", llAddr4, nicID2) + } + if ok, _ := expectPrefixEvent(); !ok { + t.Errorf("expected prefix event for %s on NIC(%d)", prefix2, nicID2) + } + if ok, _ := expectAutoGenAddrEvent(); !ok { + t.Errorf("expected auto-gen addr event for %s on NIC(%d)", e2Addr2, nicID2) + } - // Collect invalidation events after becoming a router - gotRouterEvents := make(map[ndpRouterEvent]int) - for i := 0; i < maxEvents; i++ { - ok, e := expectRouterEvent() - if !ok { - t.Errorf("expected %d router events after becoming a router; got = %d", maxEvents, i) - break - } - gotRouterEvents[e]++ - } - gotPrefixEvents := make(map[ndpPrefixEvent]int) - for i := 0; i < maxEvents; i++ { - ok, e := expectPrefixEvent() - if !ok { - t.Errorf("expected %d prefix events after becoming a router; got = %d", maxEvents, i) - break - } - gotPrefixEvents[e]++ - } - gotAutoGenAddrEvents := make(map[ndpAutoGenAddrEvent]int) - for i := 0; i < maxEvents; i++ { - ok, e := expectAutoGenAddrEvent() - if !ok { - t.Errorf("expected %d auto-generated address events after becoming a router; got = %d", maxEvents, i) - break - } - gotAutoGenAddrEvents[e]++ - } + // We should have the auto-generated addresses added. + nicinfo := s.NICInfo() + nic1Addrs := nicinfo[nicID1].ProtocolAddresses + nic2Addrs := nicinfo[nicID2].ProtocolAddresses + if !containsV6Addr(nic1Addrs, llAddrWithPrefix1) { + t.Errorf("missing %s from the list of addresses for NIC(%d): %+v", llAddrWithPrefix1, nicID1, nic1Addrs) + } + if !containsV6Addr(nic1Addrs, e1Addr1) { + t.Errorf("missing %s from the list of addresses for NIC(%d): %+v", e1Addr1, nicID1, nic1Addrs) + } + if !containsV6Addr(nic1Addrs, e1Addr2) { + t.Errorf("missing %s from the list of addresses for NIC(%d): %+v", e1Addr2, nicID1, nic1Addrs) + } + if !containsV6Addr(nic2Addrs, llAddrWithPrefix2) { + t.Errorf("missing %s from the list of addresses for NIC(%d): %+v", llAddrWithPrefix2, nicID2, nic2Addrs) + } + if !containsV6Addr(nic2Addrs, e2Addr1) { + t.Errorf("missing %s from the list of addresses for NIC(%d): %+v", e2Addr1, nicID2, nic2Addrs) + } + if !containsV6Addr(nic2Addrs, e2Addr2) { + t.Errorf("missing %s from the list of addresses for NIC(%d): %+v", e2Addr2, nicID2, nic2Addrs) + } - // No need to proceed any further if we already failed the test (missing - // some invalidation events). - if t.Failed() { - t.FailNow() - } + // We can't proceed any further if we already failed the test (missing + // some discovery/auto-generated address events or addresses). + if t.Failed() { + t.FailNow() + } - expectedRouterEvents := map[ndpRouterEvent]int{ - {nicID: nicID1, addr: llAddr3, discovered: false}: 1, - {nicID: nicID1, addr: llAddr4, discovered: false}: 1, - {nicID: nicID2, addr: llAddr3, discovered: false}: 1, - {nicID: nicID2, addr: llAddr4, discovered: false}: 1, - } - if diff := cmp.Diff(expectedRouterEvents, gotRouterEvents); diff != "" { - t.Errorf("router events mismatch (-want +got):\n%s", diff) - } - expectedPrefixEvents := map[ndpPrefixEvent]int{ - {nicID: nicID1, prefix: subnet1, discovered: false}: 1, - {nicID: nicID1, prefix: subnet2, discovered: false}: 1, - {nicID: nicID2, prefix: subnet1, discovered: false}: 1, - {nicID: nicID2, prefix: subnet2, discovered: false}: 1, - } - if diff := cmp.Diff(expectedPrefixEvents, gotPrefixEvents); diff != "" { - t.Errorf("prefix events mismatch (-want +got):\n%s", diff) - } - expectedAutoGenAddrEvents := map[ndpAutoGenAddrEvent]int{ - {nicID: nicID1, addr: e1Addr1, eventType: invalidatedAddr}: 1, - {nicID: nicID1, addr: e1Addr2, eventType: invalidatedAddr}: 1, - {nicID: nicID2, addr: e2Addr1, eventType: invalidatedAddr}: 1, - {nicID: nicID2, addr: e2Addr2, eventType: invalidatedAddr}: 1, - } - if diff := cmp.Diff(expectedAutoGenAddrEvents, gotAutoGenAddrEvents); diff != "" { - t.Errorf("auto-generated address events mismatch (-want +got):\n%s", diff) - } + test.cleanupFn(t, s) - // Make sure the auto-generated addresses got removed. - nicinfo = s.NICInfo() - nic1Addrs = nicinfo[nicID1].ProtocolAddresses - nic2Addrs = nicinfo[nicID2].ProtocolAddresses - if !containsV6Addr(nic1Addrs, llAddrWithPrefix1) { - t.Errorf("missing %s from the list of addresses for NIC(%d): %+v", llAddrWithPrefix1, nicID1, nic1Addrs) - } - if containsV6Addr(nic1Addrs, e1Addr1) { - t.Errorf("still have %s in the list of addresses for NIC(%d): %+v", e1Addr1, nicID1, nic1Addrs) - } - if containsV6Addr(nic1Addrs, e1Addr2) { - t.Errorf("still have %s in the list of addresses for NIC(%d): %+v", e1Addr2, nicID1, nic1Addrs) - } - if !containsV6Addr(nic2Addrs, llAddrWithPrefix2) { - t.Errorf("missing %s from the list of addresses for NIC(%d): %+v", llAddrWithPrefix2, nicID2, nic2Addrs) - } - if containsV6Addr(nic2Addrs, e2Addr1) { - t.Errorf("still have %s in the list of addresses for NIC(%d): %+v", e2Addr1, nicID2, nic2Addrs) - } - if containsV6Addr(nic2Addrs, e2Addr2) { - t.Errorf("still have %s in the list of addresses for NIC(%d): %+v", e2Addr2, nicID2, nic2Addrs) - } + // Collect invalidation events after having NDP state cleaned up. + gotRouterEvents := make(map[ndpRouterEvent]int) + for i := 0; i < maxRouterAndPrefixEvents; i++ { + ok, e := expectRouterEvent() + if !ok { + t.Errorf("expected %d router events after becoming a router; got = %d", maxRouterAndPrefixEvents, i) + break + } + gotRouterEvents[e]++ + } + gotPrefixEvents := make(map[ndpPrefixEvent]int) + for i := 0; i < maxRouterAndPrefixEvents; i++ { + ok, e := expectPrefixEvent() + if !ok { + t.Errorf("expected %d prefix events after becoming a router; got = %d", maxRouterAndPrefixEvents, i) + break + } + gotPrefixEvents[e]++ + } + gotAutoGenAddrEvents := make(map[ndpAutoGenAddrEvent]int) + for i := 0; i < test.maxAutoGenAddrEvents; i++ { + ok, e := expectAutoGenAddrEvent() + if !ok { + t.Errorf("expected %d auto-generated address events after becoming a router; got = %d", test.maxAutoGenAddrEvents, i) + break + } + gotAutoGenAddrEvents[e]++ + } - // Should not get any more events (invalidation timers should have been - // cancelled when we transitioned into a router). - time.Sleep(lifetimeSeconds*time.Second + defaultTimeout) - select { - case <-ndpDisp.routerC: - t.Error("unexpected router event") - default: - } - select { - case <-ndpDisp.prefixC: - t.Error("unexpected prefix event") - default: - } - select { - case <-ndpDisp.autoGenAddrC: - t.Error("unexpected auto-generated address event") - default: + // No need to proceed any further if we already failed the test (missing + // some invalidation events). + if t.Failed() { + t.FailNow() + } + + expectedRouterEvents := map[ndpRouterEvent]int{ + {nicID: nicID1, addr: llAddr3, discovered: false}: 1, + {nicID: nicID1, addr: llAddr4, discovered: false}: 1, + {nicID: nicID2, addr: llAddr3, discovered: false}: 1, + {nicID: nicID2, addr: llAddr4, discovered: false}: 1, + } + if diff := cmp.Diff(expectedRouterEvents, gotRouterEvents); diff != "" { + t.Errorf("router events mismatch (-want +got):\n%s", diff) + } + expectedPrefixEvents := map[ndpPrefixEvent]int{ + {nicID: nicID1, prefix: subnet1, discovered: false}: 1, + {nicID: nicID1, prefix: subnet2, discovered: false}: 1, + {nicID: nicID2, prefix: subnet1, discovered: false}: 1, + {nicID: nicID2, prefix: subnet2, discovered: false}: 1, + } + if diff := cmp.Diff(expectedPrefixEvents, gotPrefixEvents); diff != "" { + t.Errorf("prefix events mismatch (-want +got):\n%s", diff) + } + expectedAutoGenAddrEvents := map[ndpAutoGenAddrEvent]int{ + {nicID: nicID1, addr: e1Addr1, eventType: invalidatedAddr}: 1, + {nicID: nicID1, addr: e1Addr2, eventType: invalidatedAddr}: 1, + {nicID: nicID2, addr: e2Addr1, eventType: invalidatedAddr}: 1, + {nicID: nicID2, addr: e2Addr2, eventType: invalidatedAddr}: 1, + } + + if !test.keepAutoGenLinkLocal { + expectedAutoGenAddrEvents[ndpAutoGenAddrEvent{nicID: nicID1, addr: llAddrWithPrefix1, eventType: invalidatedAddr}] = 1 + expectedAutoGenAddrEvents[ndpAutoGenAddrEvent{nicID: nicID2, addr: llAddrWithPrefix2, eventType: invalidatedAddr}] = 1 + } + + if diff := cmp.Diff(expectedAutoGenAddrEvents, gotAutoGenAddrEvents); diff != "" { + t.Errorf("auto-generated address events mismatch (-want +got):\n%s", diff) + } + + // Make sure the auto-generated addresses got removed. + nicinfo = s.NICInfo() + nic1Addrs = nicinfo[nicID1].ProtocolAddresses + nic2Addrs = nicinfo[nicID2].ProtocolAddresses + if containsV6Addr(nic1Addrs, llAddrWithPrefix1) != test.keepAutoGenLinkLocal { + if test.keepAutoGenLinkLocal { + t.Errorf("missing %s from the list of addresses for NIC(%d): %+v", llAddrWithPrefix1, nicID1, nic1Addrs) + } else { + t.Errorf("still have %s in the list of addresses for NIC(%d): %+v", llAddrWithPrefix1, nicID1, nic1Addrs) + } + } + if containsV6Addr(nic1Addrs, e1Addr1) { + t.Errorf("still have %s in the list of addresses for NIC(%d): %+v", e1Addr1, nicID1, nic1Addrs) + } + if containsV6Addr(nic1Addrs, e1Addr2) { + t.Errorf("still have %s in the list of addresses for NIC(%d): %+v", e1Addr2, nicID1, nic1Addrs) + } + if containsV6Addr(nic2Addrs, llAddrWithPrefix2) != test.keepAutoGenLinkLocal { + if test.keepAutoGenLinkLocal { + t.Errorf("missing %s from the list of addresses for NIC(%d): %+v", llAddrWithPrefix2, nicID2, nic2Addrs) + } else { + t.Errorf("still have %s in the list of addresses for NIC(%d): %+v", llAddrWithPrefix2, nicID2, nic2Addrs) + } + } + if containsV6Addr(nic2Addrs, e2Addr1) { + t.Errorf("still have %s in the list of addresses for NIC(%d): %+v", e2Addr1, nicID2, nic2Addrs) + } + if containsV6Addr(nic2Addrs, e2Addr2) { + t.Errorf("still have %s in the list of addresses for NIC(%d): %+v", e2Addr2, nicID2, nic2Addrs) + } + + // Should not get any more events (invalidation timers should have been + // cancelled when the NDP state was cleaned up). + time.Sleep(lifetimeSeconds*time.Second + defaultTimeout) + select { + case <-ndpDisp.routerC: + t.Error("unexpected router event") + default: + } + select { + case <-ndpDisp.prefixC: + t.Error("unexpected prefix event") + default: + } + select { + case <-ndpDisp.autoGenAddrC: + t.Error("unexpected auto-generated address event") + default: + } + }) } } @@ -3406,77 +3483,130 @@ func TestRouterSolicitation(t *testing.T) { }) } -// TestStopStartSolicitingRouters tests that when forwarding is enabled or -// disabled, router solicitations are stopped or started, respecitively. func TestStopStartSolicitingRouters(t *testing.T) { t.Parallel() + const nicID = 1 const interval = 500 * time.Millisecond const delay = time.Second const maxRtrSolicitations = 3 - e := channel.New(maxRtrSolicitations, 1280, linkAddr1) - waitForPkt := func(timeout time.Duration) { - t.Helper() - ctx, _ := context.WithTimeout(context.Background(), timeout) - p, ok := e.ReadContext(ctx) - if !ok { - t.Fatal("timed out waiting for packet") - return - } - if p.Proto != header.IPv6ProtocolNumber { - t.Fatalf("got Proto = %d, want = %d", p.Proto, header.IPv6ProtocolNumber) - } - checker.IPv6(t, p.Pkt.Header.View(), - checker.SrcAddr(header.IPv6Any), - checker.DstAddr(header.IPv6AllRoutersMulticastAddress), - checker.TTL(header.NDPHopLimit), - checker.NDPRS()) - } - s := stack.New(stack.Options{ - NetworkProtocols: []stack.NetworkProtocol{ipv6.NewProtocol()}, - NDPConfigs: stack.NDPConfigurations{ - MaxRtrSolicitations: maxRtrSolicitations, - RtrSolicitationInterval: interval, - MaxRtrSolicitationDelay: delay, + tests := []struct { + name string + startFn func(t *testing.T, s *stack.Stack) + stopFn func(t *testing.T, s *stack.Stack) + }{ + // Tests that when forwarding is enabled or disabled, router solicitations + // are stopped or started, respectively. + { + name: "Forwarding enabled and disabled", + startFn: func(t *testing.T, s *stack.Stack) { + t.Helper() + s.SetForwarding(false) + }, + stopFn: func(t *testing.T, s *stack.Stack) { + t.Helper() + s.SetForwarding(true) + }, }, - }) - if err := s.CreateNIC(1, e); err != nil { - t.Fatalf("CreateNIC(1) = %s", err) - } - // Enable forwarding which should stop router solicitations. - s.SetForwarding(true) - ctx, _ := context.WithTimeout(context.Background(), delay+defaultTimeout) - if _, ok := e.ReadContext(ctx); ok { - // A single RS may have been sent before forwarding was enabled. - ctx, _ = context.WithTimeout(context.Background(), interval+defaultTimeout) - if _, ok = e.ReadContext(ctx); ok { - t.Fatal("Should not have sent more than one RS message") - } - } + // Tests that when a NIC is enabled or disabled, router solicitations + // are started or stopped, respectively. + { + name: "NIC disabled and enabled", + startFn: func(t *testing.T, s *stack.Stack) { + t.Helper() - // Enabling forwarding again should do nothing. - s.SetForwarding(true) - ctx, _ = context.WithTimeout(context.Background(), delay+defaultTimeout) - if _, ok := e.ReadContext(ctx); ok { - t.Fatal("unexpectedly got a packet after becoming a router") - } + if err := s.EnableNIC(nicID); err != nil { + t.Fatalf("s.EnableNIC(%d): %s", nicID, err) + } + }, + stopFn: func(t *testing.T, s *stack.Stack) { + t.Helper() - // Disable forwarding which should start router solicitations. - s.SetForwarding(false) - waitForPkt(delay + defaultAsyncEventTimeout) - waitForPkt(interval + defaultAsyncEventTimeout) - waitForPkt(interval + defaultAsyncEventTimeout) - ctx, _ = context.WithTimeout(context.Background(), interval+defaultTimeout) - if _, ok := e.ReadContext(ctx); ok { - t.Fatal("unexpectedly got an extra packet after sending out the expected RSs") + if err := s.DisableNIC(nicID); err != nil { + t.Fatalf("s.DisableNIC(%d): %s", nicID, err) + } + }, + }, } - // Disabling forwarding again should do nothing. - s.SetForwarding(false) - ctx, _ = context.WithTimeout(context.Background(), delay+defaultTimeout) - if _, ok := e.ReadContext(ctx); ok { - t.Fatal("unexpectedly got a packet after becoming a router") + for _, test := range tests { + t.Run(test.name, func(t *testing.T) { + e := channel.New(maxRtrSolicitations, 1280, linkAddr1) + waitForPkt := func(timeout time.Duration) { + t.Helper() + + ctx, cancel := context.WithTimeout(context.Background(), timeout) + defer cancel() + p, ok := e.ReadContext(ctx) + if !ok { + t.Fatal("timed out waiting for packet") + return + } + + if p.Proto != header.IPv6ProtocolNumber { + t.Fatalf("got Proto = %d, want = %d", p.Proto, header.IPv6ProtocolNumber) + } + checker.IPv6(t, p.Pkt.Header.View(), + checker.SrcAddr(header.IPv6Any), + checker.DstAddr(header.IPv6AllRoutersMulticastAddress), + checker.TTL(header.NDPHopLimit), + checker.NDPRS()) + } + s := stack.New(stack.Options{ + NetworkProtocols: []stack.NetworkProtocol{ipv6.NewProtocol()}, + NDPConfigs: stack.NDPConfigurations{ + MaxRtrSolicitations: maxRtrSolicitations, + RtrSolicitationInterval: interval, + MaxRtrSolicitationDelay: delay, + }, + }) + if err := s.CreateNIC(nicID, e); err != nil { + t.Fatalf("CreateNIC(%d, _) = %s", nicID, err) + } + + // Stop soliciting routers. + test.stopFn(t, s) + ctx, cancel := context.WithTimeout(context.Background(), delay+defaultTimeout) + defer cancel() + if _, ok := e.ReadContext(ctx); ok { + // A single RS may have been sent before forwarding was enabled. + ctx, cancel := context.WithTimeout(context.Background(), interval+defaultTimeout) + defer cancel() + if _, ok = e.ReadContext(ctx); ok { + t.Fatal("should not have sent more than one RS message") + } + } + + // Stopping router solicitations after it has already been stopped should + // do nothing. + test.stopFn(t, s) + ctx, cancel = context.WithTimeout(context.Background(), delay+defaultTimeout) + defer cancel() + if _, ok := e.ReadContext(ctx); ok { + t.Fatal("unexpectedly got a packet after router solicitation has been stopepd") + } + + // Start soliciting routers. + test.startFn(t, s) + waitForPkt(delay + defaultAsyncEventTimeout) + waitForPkt(interval + defaultAsyncEventTimeout) + waitForPkt(interval + defaultAsyncEventTimeout) + ctx, cancel = context.WithTimeout(context.Background(), interval+defaultTimeout) + defer cancel() + if _, ok := e.ReadContext(ctx); ok { + t.Fatal("unexpectedly got an extra packet after sending out the expected RSs") + } + + // Starting router solicitations after it has already completed should do + // nothing. + test.startFn(t, s) + ctx, cancel = context.WithTimeout(context.Background(), delay+defaultTimeout) + defer cancel() + if _, ok := e.ReadContext(ctx); ok { + t.Fatal("unexpectedly got a packet after finishing router solicitations") + } + }) } } diff --git a/pkg/tcpip/stack/nic.go b/pkg/tcpip/stack/nic.go index ca3a7a07e..b2be18e47 100644 --- a/pkg/tcpip/stack/nic.go +++ b/pkg/tcpip/stack/nic.go @@ -27,6 +27,14 @@ import ( "gvisor.dev/gvisor/pkg/tcpip/header" ) +var ipv4BroadcastAddr = tcpip.ProtocolAddress{ + Protocol: header.IPv4ProtocolNumber, + AddressWithPrefix: tcpip.AddressWithPrefix{ + Address: header.IPv4Broadcast, + PrefixLen: 8 * header.IPv4AddressSize, + }, +} + // NIC represents a "network interface card" to which the networking stack is // attached. type NIC struct { @@ -36,7 +44,8 @@ type NIC struct { linkEP LinkEndpoint context NICContext - stats NICStats + stats NICStats + attach sync.Once mu struct { sync.RWMutex @@ -135,7 +144,69 @@ func newNIC(stack *Stack, id tcpip.NICID, name string, ep LinkEndpoint, ctx NICC return nic } -// enable enables the NIC. enable will attach the link to its LinkEndpoint and +// enabled returns true if n is enabled. +func (n *NIC) enabled() bool { + n.mu.RLock() + enabled := n.mu.enabled + n.mu.RUnlock() + return enabled +} + +// disable disables n. +// +// It undoes the work done by enable. +func (n *NIC) disable() *tcpip.Error { + n.mu.RLock() + enabled := n.mu.enabled + n.mu.RUnlock() + if !enabled { + return nil + } + + n.mu.Lock() + defer n.mu.Unlock() + + if !n.mu.enabled { + return nil + } + + // TODO(b/147015577): Should Routes that are currently bound to n be + // invalidated? Currently, Routes will continue to work when a NIC is enabled + // again, and applications may not know that the underlying NIC was ever + // disabled. + + if _, ok := n.stack.networkProtocols[header.IPv6ProtocolNumber]; ok { + n.mu.ndp.stopSolicitingRouters() + n.mu.ndp.cleanupState(false /* hostOnly */) + + // Stop DAD for all the unicast IPv6 endpoints that are in the + // permanentTentative state. + for _, r := range n.mu.endpoints { + if addr := r.ep.ID().LocalAddress; r.getKind() == permanentTentative && header.IsV6UnicastAddress(addr) { + n.mu.ndp.stopDuplicateAddressDetection(addr) + } + } + + // The NIC may have already left the multicast group. + if err := n.leaveGroupLocked(header.IPv6AllNodesMulticastAddress); err != nil && err != tcpip.ErrBadLocalAddress { + return err + } + } + + if _, ok := n.stack.networkProtocols[header.IPv4ProtocolNumber]; ok { + // The address may have already been removed. + if err := n.removePermanentAddressLocked(ipv4BroadcastAddr.AddressWithPrefix.Address); err != nil && err != tcpip.ErrBadLocalAddress { + return err + } + } + + // TODO(b/147015577): Should n detach from its LinkEndpoint? + + n.mu.enabled = false + return nil +} + +// enable enables n. enable will attach the nic to its LinkEndpoint and // join the IPv6 All-Nodes Multicast address (ff02::1). func (n *NIC) enable() *tcpip.Error { n.mu.RLock() @@ -158,10 +229,7 @@ func (n *NIC) enable() *tcpip.Error { // Create an endpoint to receive broadcast packets on this interface. if _, ok := n.stack.networkProtocols[header.IPv4ProtocolNumber]; ok { - if _, err := n.addAddressLocked(tcpip.ProtocolAddress{ - Protocol: header.IPv4ProtocolNumber, - AddressWithPrefix: tcpip.AddressWithPrefix{header.IPv4Broadcast, 8 * header.IPv4AddressSize}, - }, NeverPrimaryEndpoint, permanent, static, false /* deprecated */); err != nil { + if _, err := n.addAddressLocked(ipv4BroadcastAddr, NeverPrimaryEndpoint, permanent, static, false /* deprecated */); err != nil { return err } } @@ -183,6 +251,14 @@ func (n *NIC) enable() *tcpip.Error { return nil } + // Join the All-Nodes multicast group before starting DAD as responses to DAD + // (NDP NS) messages may be sent to the All-Nodes multicast group if the + // source address of the NDP NS is the unspecified address, as per RFC 4861 + // section 7.2.4. + if err := n.joinGroupLocked(header.IPv6ProtocolNumber, header.IPv6AllNodesMulticastAddress); err != nil { + return err + } + // Perform DAD on the all the unicast IPv6 endpoints that are in the permanent // state. // @@ -200,10 +276,6 @@ func (n *NIC) enable() *tcpip.Error { } } - if err := n.joinGroupLocked(header.IPv6ProtocolNumber, header.IPv6AllNodesMulticastAddress); err != nil { - return err - } - // Do not auto-generate an IPv6 link-local address for loopback devices. if n.stack.autoGenIPv6LinkLocal && !n.isLoopback() { // The valid and preferred lifetime is infinite for the auto-generated @@ -234,7 +306,7 @@ func (n *NIC) becomeIPv6Router() { n.mu.Lock() defer n.mu.Unlock() - n.mu.ndp.cleanupHostOnlyState() + n.mu.ndp.cleanupState(true /* hostOnly */) n.mu.ndp.stopSolicitingRouters() } @@ -252,7 +324,9 @@ func (n *NIC) becomeIPv6Host() { // attachLinkEndpoint attaches the NIC to the endpoint, which will enable it // to start delivering packets. func (n *NIC) attachLinkEndpoint() { - n.linkEP.Attach(n) + n.attach.Do(func() { + n.linkEP.Attach(n) + }) } // setPromiscuousMode enables or disables promiscuous mode. @@ -712,6 +786,7 @@ func (n *NIC) AllAddresses() []tcpip.ProtocolAddress { case permanentExpired, temporary: continue } + addrs = append(addrs, tcpip.ProtocolAddress{ Protocol: ref.protocol, AddressWithPrefix: tcpip.AddressWithPrefix{ @@ -1009,6 +1084,15 @@ func (n *NIC) leaveGroupLocked(addr tcpip.Address) *tcpip.Error { return nil } +// isInGroup returns true if n has joined the multicast group addr. +func (n *NIC) isInGroup(addr tcpip.Address) bool { + n.mu.RLock() + joins := n.mu.mcastJoins[NetworkEndpointID{addr}] + n.mu.RUnlock() + + return joins != 0 +} + func handlePacket(protocol tcpip.NetworkProtocolNumber, dst, src tcpip.Address, localLinkAddr, remotelinkAddr tcpip.LinkAddress, ref *referencedNetworkEndpoint, pkt tcpip.PacketBuffer) { r := makeRoute(protocol, dst, src, localLinkAddr, ref, false /* handleLocal */, false /* multicastLoop */) r.RemoteLinkAddress = remotelinkAddr @@ -1411,7 +1495,7 @@ func (r *referencedNetworkEndpoint) isValidForOutgoing() bool { // // r's NIC must be read locked. func (r *referencedNetworkEndpoint) isValidForOutgoingRLocked() bool { - return r.getKind() != permanentExpired || r.nic.mu.spoofing + return r.nic.mu.enabled && (r.getKind() != permanentExpired || r.nic.mu.spoofing) } // decRef decrements the ref count and cleans up the endpoint once it reaches diff --git a/pkg/tcpip/stack/stack.go b/pkg/tcpip/stack/stack.go index 6eac16e16..fabc976a7 100644 --- a/pkg/tcpip/stack/stack.go +++ b/pkg/tcpip/stack/stack.go @@ -921,23 +921,38 @@ func (s *Stack) EnableNIC(id tcpip.NICID) *tcpip.Error { s.mu.RLock() defer s.mu.RUnlock() - nic := s.nics[id] - if nic == nil { + nic, ok := s.nics[id] + if !ok { return tcpip.ErrUnknownNICID } return nic.enable() } +// DisableNIC disables the given NIC. +func (s *Stack) DisableNIC(id tcpip.NICID) *tcpip.Error { + s.mu.RLock() + defer s.mu.RUnlock() + + nic, ok := s.nics[id] + if !ok { + return tcpip.ErrUnknownNICID + } + + return nic.disable() +} + // CheckNIC checks if a NIC is usable. func (s *Stack) CheckNIC(id tcpip.NICID) bool { s.mu.RLock() + defer s.mu.RUnlock() + nic, ok := s.nics[id] - s.mu.RUnlock() - if ok { - return nic.linkEP.IsAttached() + if !ok { + return false } - return false + + return nic.enabled() } // NICAddressRanges returns a map of NICIDs to their associated subnets. @@ -989,7 +1004,7 @@ func (s *Stack) NICInfo() map[tcpip.NICID]NICInfo { for id, nic := range s.nics { flags := NICStateFlags{ Up: true, // Netstack interfaces are always up. - Running: nic.linkEP.IsAttached(), + Running: nic.enabled(), Promiscuous: nic.isPromiscuousMode(), Loopback: nic.isLoopback(), } @@ -1151,7 +1166,7 @@ func (s *Stack) FindRoute(id tcpip.NICID, localAddr, remoteAddr tcpip.Address, n isMulticast := header.IsV4MulticastAddress(remoteAddr) || header.IsV6MulticastAddress(remoteAddr) needRoute := !(isBroadcast || isMulticast || header.IsV6LinkLocalAddress(remoteAddr)) if id != 0 && !needRoute { - if nic, ok := s.nics[id]; ok { + if nic, ok := s.nics[id]; ok && nic.enabled() { if ref := s.getRefEP(nic, localAddr, remoteAddr, netProto); ref != nil { return makeRoute(netProto, ref.ep.ID().LocalAddress, remoteAddr, nic.linkEP.LinkAddress(), ref, s.handleLocal && !nic.isLoopback(), multicastLoop && !nic.isLoopback()), nil } @@ -1161,7 +1176,7 @@ func (s *Stack) FindRoute(id tcpip.NICID, localAddr, remoteAddr tcpip.Address, n if (id != 0 && id != route.NIC) || (len(remoteAddr) != 0 && !route.Destination.Contains(remoteAddr)) { continue } - if nic, ok := s.nics[route.NIC]; ok { + if nic, ok := s.nics[route.NIC]; ok && nic.enabled() { if ref := s.getRefEP(nic, localAddr, remoteAddr, netProto); ref != nil { if len(remoteAddr) == 0 { // If no remote address was provided, then the route @@ -1614,6 +1629,18 @@ func (s *Stack) LeaveGroup(protocol tcpip.NetworkProtocolNumber, nicID tcpip.NIC return tcpip.ErrUnknownNICID } +// IsInGroup returns true if the NIC with ID nicID has joined the multicast +// group multicastAddr. +func (s *Stack) IsInGroup(nicID tcpip.NICID, multicastAddr tcpip.Address) (bool, *tcpip.Error) { + s.mu.RLock() + defer s.mu.RUnlock() + + if nic, ok := s.nics[nicID]; ok { + return nic.isInGroup(multicastAddr), nil + } + return false, tcpip.ErrUnknownNICID +} + // IPTables returns the stack's iptables. func (s *Stack) IPTables() iptables.IPTables { s.tablesMu.RLock() diff --git a/pkg/tcpip/stack/stack_test.go b/pkg/tcpip/stack/stack_test.go index 7ba604442..eb6f7d1fc 100644 --- a/pkg/tcpip/stack/stack_test.go +++ b/pkg/tcpip/stack/stack_test.go @@ -33,6 +33,7 @@ import ( "gvisor.dev/gvisor/pkg/tcpip/header" "gvisor.dev/gvisor/pkg/tcpip/link/channel" "gvisor.dev/gvisor/pkg/tcpip/link/loopback" + "gvisor.dev/gvisor/pkg/tcpip/network/ipv4" "gvisor.dev/gvisor/pkg/tcpip/network/ipv6" "gvisor.dev/gvisor/pkg/tcpip/stack" "gvisor.dev/gvisor/pkg/tcpip/transport/udp" @@ -509,6 +510,257 @@ func testNoRoute(t *testing.T, s *stack.Stack, nic tcpip.NICID, srcAddr, dstAddr } } +func TestDisableUnknownNIC(t *testing.T) { + s := stack.New(stack.Options{ + NetworkProtocols: []stack.NetworkProtocol{fakeNetFactory()}, + }) + + if err := s.DisableNIC(1); err != tcpip.ErrUnknownNICID { + t.Fatalf("got s.DisableNIC(1) = %v, want = %s", err, tcpip.ErrUnknownNICID) + } +} + +func TestDisabledNICsNICInfoAndCheckNIC(t *testing.T) { + const nicID = 1 + + s := stack.New(stack.Options{ + NetworkProtocols: []stack.NetworkProtocol{fakeNetFactory()}, + }) + + e := loopback.New() + nicOpts := stack.NICOptions{Disabled: true} + if err := s.CreateNICWithOptions(nicID, e, nicOpts); err != nil { + t.Fatalf("CreateNICWithOptions(%d, _, %+v) = %s", nicID, nicOpts, err) + } + + checkNIC := func(enabled bool) { + t.Helper() + + allNICInfo := s.NICInfo() + nicInfo, ok := allNICInfo[nicID] + if !ok { + t.Errorf("entry for %d missing from allNICInfo = %+v", nicID, allNICInfo) + } else if nicInfo.Flags.Running != enabled { + t.Errorf("got nicInfo.Flags.Running = %t, want = %t", nicInfo.Flags.Running, enabled) + } + + if got := s.CheckNIC(nicID); got != enabled { + t.Errorf("got s.CheckNIC(%d) = %t, want = %t", nicID, got, enabled) + } + } + + // NIC should initially report itself as disabled. + checkNIC(false) + + if err := s.EnableNIC(nicID); err != nil { + t.Fatalf("s.EnableNIC(%d): %s", nicID, err) + } + checkNIC(true) + + // If the NIC is not reporting a correct enabled status, we cannot trust the + // next check so end the test here. + if t.Failed() { + t.FailNow() + } + + if err := s.DisableNIC(nicID); err != nil { + t.Fatalf("s.DisableNIC(%d): %s", nicID, err) + } + checkNIC(false) +} + +func TestRoutesWithDisabledNIC(t *testing.T) { + const unspecifiedNIC = 0 + const nicID1 = 1 + const nicID2 = 2 + + s := stack.New(stack.Options{ + NetworkProtocols: []stack.NetworkProtocol{fakeNetFactory()}, + }) + + ep1 := channel.New(0, defaultMTU, "") + if err := s.CreateNIC(nicID1, ep1); err != nil { + t.Fatalf("CreateNIC(%d, _): %s", nicID1, err) + } + + addr1 := tcpip.Address("\x01") + if err := s.AddAddress(nicID1, fakeNetNumber, addr1); err != nil { + t.Fatalf("AddAddress(%d, %d, %s): %s", nicID1, fakeNetNumber, addr1, err) + } + + ep2 := channel.New(0, defaultMTU, "") + if err := s.CreateNIC(nicID2, ep2); err != nil { + t.Fatalf("CreateNIC(%d, _): %s", nicID2, err) + } + + addr2 := tcpip.Address("\x02") + if err := s.AddAddress(nicID2, fakeNetNumber, addr2); err != nil { + t.Fatalf("AddAddress(%d, %d, %s): %s", nicID2, fakeNetNumber, addr2, err) + } + + // Set a route table that sends all packets with odd destination + // addresses through the first NIC, and all even destination address + // through the second one. + { + subnet0, err := tcpip.NewSubnet("\x00", "\x01") + if err != nil { + t.Fatal(err) + } + subnet1, err := tcpip.NewSubnet("\x01", "\x01") + if err != nil { + t.Fatal(err) + } + s.SetRouteTable([]tcpip.Route{ + {Destination: subnet1, Gateway: "\x00", NIC: nicID1}, + {Destination: subnet0, Gateway: "\x00", NIC: nicID2}, + }) + } + + // Test routes to odd address. + testRoute(t, s, unspecifiedNIC, "", "\x05", addr1) + testRoute(t, s, unspecifiedNIC, addr1, "\x05", addr1) + testRoute(t, s, nicID1, addr1, "\x05", addr1) + + // Test routes to even address. + testRoute(t, s, unspecifiedNIC, "", "\x06", addr2) + testRoute(t, s, unspecifiedNIC, addr2, "\x06", addr2) + testRoute(t, s, nicID2, addr2, "\x06", addr2) + + // Disabling NIC1 should result in no routes to odd addresses. Routes to even + // addresses should continue to be available as NIC2 is still enabled. + if err := s.DisableNIC(nicID1); err != nil { + t.Fatalf("s.DisableNIC(%d): %s", nicID1, err) + } + nic1Dst := tcpip.Address("\x05") + testNoRoute(t, s, unspecifiedNIC, "", nic1Dst) + testNoRoute(t, s, unspecifiedNIC, addr1, nic1Dst) + testNoRoute(t, s, nicID1, addr1, nic1Dst) + nic2Dst := tcpip.Address("\x06") + testRoute(t, s, unspecifiedNIC, "", nic2Dst, addr2) + testRoute(t, s, unspecifiedNIC, addr2, nic2Dst, addr2) + testRoute(t, s, nicID2, addr2, nic2Dst, addr2) + + // Disabling NIC2 should result in no routes to even addresses. No route + // should be available to any address as routes to odd addresses were made + // unavailable by disabling NIC1 above. + if err := s.DisableNIC(nicID2); err != nil { + t.Fatalf("s.DisableNIC(%d): %s", nicID2, err) + } + testNoRoute(t, s, unspecifiedNIC, "", nic1Dst) + testNoRoute(t, s, unspecifiedNIC, addr1, nic1Dst) + testNoRoute(t, s, nicID1, addr1, nic1Dst) + testNoRoute(t, s, unspecifiedNIC, "", nic2Dst) + testNoRoute(t, s, unspecifiedNIC, addr2, nic2Dst) + testNoRoute(t, s, nicID2, addr2, nic2Dst) + + // Enabling NIC1 should make routes to odd addresses available again. Routes + // to even addresses should continue to be unavailable as NIC2 is still + // disabled. + if err := s.EnableNIC(nicID1); err != nil { + t.Fatalf("s.EnableNIC(%d): %s", nicID1, err) + } + testRoute(t, s, unspecifiedNIC, "", nic1Dst, addr1) + testRoute(t, s, unspecifiedNIC, addr1, nic1Dst, addr1) + testRoute(t, s, nicID1, addr1, nic1Dst, addr1) + testNoRoute(t, s, unspecifiedNIC, "", nic2Dst) + testNoRoute(t, s, unspecifiedNIC, addr2, nic2Dst) + testNoRoute(t, s, nicID2, addr2, nic2Dst) +} + +func TestRouteWritePacketWithDisabledNIC(t *testing.T) { + const unspecifiedNIC = 0 + const nicID1 = 1 + const nicID2 = 2 + + s := stack.New(stack.Options{ + NetworkProtocols: []stack.NetworkProtocol{fakeNetFactory()}, + }) + + ep1 := channel.New(1, defaultMTU, "") + if err := s.CreateNIC(nicID1, ep1); err != nil { + t.Fatalf("CreateNIC(%d, _): %s", nicID1, err) + } + + addr1 := tcpip.Address("\x01") + if err := s.AddAddress(nicID1, fakeNetNumber, addr1); err != nil { + t.Fatalf("AddAddress(%d, %d, %s): %s", nicID1, fakeNetNumber, addr1, err) + } + + ep2 := channel.New(1, defaultMTU, "") + if err := s.CreateNIC(nicID2, ep2); err != nil { + t.Fatalf("CreateNIC(%d, _): %s", nicID2, err) + } + + addr2 := tcpip.Address("\x02") + if err := s.AddAddress(nicID2, fakeNetNumber, addr2); err != nil { + t.Fatalf("AddAddress(%d, %d, %s): %s", nicID2, fakeNetNumber, addr2, err) + } + + // Set a route table that sends all packets with odd destination + // addresses through the first NIC, and all even destination address + // through the second one. + { + subnet0, err := tcpip.NewSubnet("\x00", "\x01") + if err != nil { + t.Fatal(err) + } + subnet1, err := tcpip.NewSubnet("\x01", "\x01") + if err != nil { + t.Fatal(err) + } + s.SetRouteTable([]tcpip.Route{ + {Destination: subnet1, Gateway: "\x00", NIC: nicID1}, + {Destination: subnet0, Gateway: "\x00", NIC: nicID2}, + }) + } + + nic1Dst := tcpip.Address("\x05") + r1, err := s.FindRoute(nicID1, addr1, nic1Dst, fakeNetNumber, false /* multicastLoop */) + if err != nil { + t.Errorf("FindRoute(%d, %s, %s, %d, false): %s", nicID1, addr1, nic1Dst, fakeNetNumber, err) + } + defer r1.Release() + + nic2Dst := tcpip.Address("\x06") + r2, err := s.FindRoute(nicID2, addr2, nic2Dst, fakeNetNumber, false /* multicastLoop */) + if err != nil { + t.Errorf("FindRoute(%d, %s, %s, %d, false): %s", nicID2, addr2, nic2Dst, fakeNetNumber, err) + } + defer r2.Release() + + // If we failed to get routes r1 or r2, we cannot proceed with the test. + if t.Failed() { + t.FailNow() + } + + buf := buffer.View([]byte{1}) + testSend(t, r1, ep1, buf) + testSend(t, r2, ep2, buf) + + // Writes with Routes that use the disabled NIC1 should fail. + if err := s.DisableNIC(nicID1); err != nil { + t.Fatalf("s.DisableNIC(%d): %s", nicID1, err) + } + testFailingSend(t, r1, ep1, buf, tcpip.ErrInvalidEndpointState) + testSend(t, r2, ep2, buf) + + // Writes with Routes that use the disabled NIC2 should fail. + if err := s.DisableNIC(nicID2); err != nil { + t.Fatalf("s.DisableNIC(%d): %s", nicID2, err) + } + testFailingSend(t, r1, ep1, buf, tcpip.ErrInvalidEndpointState) + testFailingSend(t, r2, ep2, buf, tcpip.ErrInvalidEndpointState) + + // Writes with Routes that use the re-enabled NIC1 should succeed. + // TODO(b/147015577): Should we instead completely invalidate all Routes that + // were bound to a disabled NIC at some point? + if err := s.EnableNIC(nicID1); err != nil { + t.Fatalf("s.EnableNIC(%d): %s", nicID1, err) + } + testSend(t, r1, ep1, buf) + testFailingSend(t, r2, ep2, buf, tcpip.ErrInvalidEndpointState) +} + func TestRoutes(t *testing.T) { // Create a stack with the fake network protocol, two nics, and two // addresses per nic, the first nic has odd address, the second one has @@ -2173,13 +2425,29 @@ func TestNICAutoGenLinkLocalAddr(t *testing.T) { e := channel.New(0, 1280, test.linkAddr) s := stack.New(opts) - nicOpts := stack.NICOptions{Name: test.nicName} + nicOpts := stack.NICOptions{Name: test.nicName, Disabled: true} if err := s.CreateNICWithOptions(nicID, e, nicOpts); err != nil { t.Fatalf("CreateNICWithOptions(%d, _, %+v) = %s", nicID, opts, err) } - var expectedMainAddr tcpip.AddressWithPrefix + // A new disabled NIC should not have any address, even if auto generation + // was enabled. + allStackAddrs := s.AllAddresses() + allNICAddrs, ok := allStackAddrs[nicID] + if !ok { + t.Fatalf("entry for %d missing from allStackAddrs = %+v", nicID, allStackAddrs) + } + if l := len(allNICAddrs); l != 0 { + t.Fatalf("got len(allNICAddrs) = %d, want = 0", l) + } + // Enabling the NIC should attempt auto-generation of a link-local + // address. + if err := s.EnableNIC(nicID); err != nil { + t.Fatalf("s.EnableNIC(%d): %s", nicID, err) + } + + var expectedMainAddr tcpip.AddressWithPrefix if test.shouldGen { expectedMainAddr = tcpip.AddressWithPrefix{ Address: test.expectedAddr, @@ -2609,6 +2877,111 @@ func TestIPv6SourceAddressSelectionScopeAndSameAddress(t *testing.T) { } } +func TestAddRemoveIPv4BroadcastAddressOnNICEnableDisable(t *testing.T) { + const nicID = 1 + + e := loopback.New() + s := stack.New(stack.Options{ + NetworkProtocols: []stack.NetworkProtocol{ipv4.NewProtocol()}, + }) + nicOpts := stack.NICOptions{Disabled: true} + if err := s.CreateNICWithOptions(nicID, e, nicOpts); err != nil { + t.Fatalf("CreateNIC(%d, _, %+v) = %s", nicID, nicOpts, err) + } + + allStackAddrs := s.AllAddresses() + allNICAddrs, ok := allStackAddrs[nicID] + if !ok { + t.Fatalf("entry for %d missing from allStackAddrs = %+v", nicID, allStackAddrs) + } + if l := len(allNICAddrs); l != 0 { + t.Fatalf("got len(allNICAddrs) = %d, want = 0", l) + } + + // Enabling the NIC should add the IPv4 broadcast address. + if err := s.EnableNIC(nicID); err != nil { + t.Fatalf("s.EnableNIC(%d): %s", nicID, err) + } + allStackAddrs = s.AllAddresses() + allNICAddrs, ok = allStackAddrs[nicID] + if !ok { + t.Fatalf("entry for %d missing from allStackAddrs = %+v", nicID, allStackAddrs) + } + if l := len(allNICAddrs); l != 1 { + t.Fatalf("got len(allNICAddrs) = %d, want = 1", l) + } + want := tcpip.ProtocolAddress{ + Protocol: header.IPv4ProtocolNumber, + AddressWithPrefix: tcpip.AddressWithPrefix{ + Address: header.IPv4Broadcast, + PrefixLen: 32, + }, + } + if allNICAddrs[0] != want { + t.Fatalf("got allNICAddrs[0] = %+v, want = %+v", allNICAddrs[0], want) + } + + // Disabling the NIC should remove the IPv4 broadcast address. + if err := s.DisableNIC(nicID); err != nil { + t.Fatalf("s.DisableNIC(%d): %s", nicID, err) + } + allStackAddrs = s.AllAddresses() + allNICAddrs, ok = allStackAddrs[nicID] + if !ok { + t.Fatalf("entry for %d missing from allStackAddrs = %+v", nicID, allStackAddrs) + } + if l := len(allNICAddrs); l != 0 { + t.Fatalf("got len(allNICAddrs) = %d, want = 0", l) + } +} + +func TestJoinLeaveAllNodesMulticastOnNICEnableDisable(t *testing.T) { + const nicID = 1 + + e := loopback.New() + s := stack.New(stack.Options{ + NetworkProtocols: []stack.NetworkProtocol{ipv6.NewProtocol()}, + }) + nicOpts := stack.NICOptions{Disabled: true} + if err := s.CreateNICWithOptions(nicID, e, nicOpts); err != nil { + t.Fatalf("CreateNIC(%d, _, %+v) = %s", nicID, nicOpts, err) + } + + // Should not be in the IPv6 all-nodes multicast group yet because the NIC has + // not been enabled yet. + isInGroup, err := s.IsInGroup(nicID, header.IPv6AllNodesMulticastAddress) + if err != nil { + t.Fatalf("IsInGroup(%d, %s): %s", nicID, header.IPv6AllNodesMulticastAddress, err) + } + if isInGroup { + t.Fatalf("got IsInGroup(%d, %s) = true, want = false", nicID, header.IPv6AllNodesMulticastAddress) + } + + // The all-nodes multicast group should be joined when the NIC is enabled. + if err := s.EnableNIC(nicID); err != nil { + t.Fatalf("s.EnableNIC(%d): %s", nicID, err) + } + isInGroup, err = s.IsInGroup(nicID, header.IPv6AllNodesMulticastAddress) + if err != nil { + t.Fatalf("IsInGroup(%d, %s): %s", nicID, header.IPv6AllNodesMulticastAddress, err) + } + if !isInGroup { + t.Fatalf("got IsInGroup(%d, %s) = false, want = true", nicID, header.IPv6AllNodesMulticastAddress) + } + + // The all-nodes multicast group should be left when the NIC is disabled. + if err := s.DisableNIC(nicID); err != nil { + t.Fatalf("s.DisableNIC(%d): %s", nicID, err) + } + isInGroup, err = s.IsInGroup(nicID, header.IPv6AllNodesMulticastAddress) + if err != nil { + t.Fatalf("IsInGroup(%d, %s): %s", nicID, header.IPv6AllNodesMulticastAddress, err) + } + if isInGroup { + t.Fatalf("got IsInGroup(%d, %s) = true, want = false", nicID, header.IPv6AllNodesMulticastAddress) + } +} + // TestDoDADWhenNICEnabled tests that IPv6 endpoints that were added while a NIC // was disabled have DAD performed on them when the NIC is enabled. func TestDoDADWhenNICEnabled(t *testing.T) { -- cgit v1.2.3