diff options
Diffstat (limited to 'pkg/tcpip')
-rw-r--r-- | pkg/tcpip/stack/neighbor_cache.go | 10 | ||||
-rw-r--r-- | pkg/tcpip/stack/neighbor_cache_test.go | 3 | ||||
-rw-r--r-- | pkg/tcpip/stack/neighbor_entry.go | 57 | ||||
-rw-r--r-- | pkg/tcpip/stack/neighbor_entry_test.go | 192 | ||||
-rw-r--r-- | pkg/tcpip/stack/neighborstate_string.go | 7 |
5 files changed, 195 insertions, 74 deletions
diff --git a/pkg/tcpip/stack/neighbor_cache.go b/pkg/tcpip/stack/neighbor_cache.go index a77fe575a..533287c4c 100644 --- a/pkg/tcpip/stack/neighbor_cache.go +++ b/pkg/tcpip/stack/neighbor_cache.go @@ -25,9 +25,13 @@ const neighborCacheSize = 512 // max entries per interface // NeighborStats holds metrics for the neighbor table. type NeighborStats struct { - // FailedEntryLookups counts the number of lookups performed on an entry in - // Failed state. + // FailedEntryLookups is deprecated; UnreachableEntryLookups should be used + // instead. FailedEntryLookups *tcpip.StatCounter + + // UnreachableEntryLookups counts the number of lookups performed on an + // entry in Unreachable state. + UnreachableEntryLookups *tcpip.StatCounter } // neighborCache maps IP addresses to link addresses. It uses the Least @@ -143,7 +147,7 @@ func (n *neighborCache) entry(remoteAddr, localAddr tcpip.Address, onResolve fun onResolve(LinkResolutionResult{LinkAddress: entry.mu.neigh.LinkAddr, Success: true}) } return entry.mu.neigh, nil, nil - case Unknown, Incomplete, Failed: + case Unknown, Incomplete, Unreachable: if onResolve != nil { entry.mu.onResolve = append(entry.mu.onResolve, onResolve) } diff --git a/pkg/tcpip/stack/neighbor_cache_test.go b/pkg/tcpip/stack/neighbor_cache_test.go index d60a49fe8..909912662 100644 --- a/pkg/tcpip/stack/neighbor_cache_test.go +++ b/pkg/tcpip/stack/neighbor_cache_test.go @@ -1610,12 +1610,11 @@ func TestNeighborCacheRetryResolution(t *testing.T) { } } - // Verify the entry is in Failed state. wantEntries := []NeighborEntry{ { Addr: entry.Addr, LinkAddr: "", - State: Failed, + State: Unreachable, }, } if diff := cmp.Diff(linkRes.neigh.entries(), wantEntries, entryDiffOptsWithSort()...); diff != "" { diff --git a/pkg/tcpip/stack/neighbor_entry.go b/pkg/tcpip/stack/neighbor_entry.go index 4ed149ee8..03fef52ee 100644 --- a/pkg/tcpip/stack/neighbor_entry.go +++ b/pkg/tcpip/stack/neighbor_entry.go @@ -38,7 +38,8 @@ type NeighborEntry struct { } // NeighborState defines the state of a NeighborEntry within the Neighbor -// Unreachability Detection state machine, as per RFC 4861 section 7.3.2. +// Unreachability Detection state machine, as per RFC 4861 section 7.3.2 and +// RFC 7048. type NeighborState uint8 const ( @@ -61,13 +62,24 @@ const ( Delay // Probe means a reachability confirmation is actively being sought by // periodically retransmitting reachability probes until a reachability - // confirmation is received, or until the max amount of probes has been sent. + // confirmation is received, or until the maximum number of probes has been + // sent. Probe // Static describes entries that have been explicitly added by the user. They // do not expire and are not deleted until explicitly removed. Static - // Failed means recent attempts of reachability have returned inconclusive. + // Failed is deprecated and should no longer be used. + // + // TODO(gvisor.dev/issue/4667): Remove this once all references to Failed + // are removed from Fuchsia. Failed + // Unreachable means reachability confirmation failed; the maximum number of + // reachability probes has been sent and no replies have been received. + // + // TODO(gvisor.dev/issue/5472): Add the following sentence when we implement + // RFC 7048: "Packets continue to be sent to the neighbor while + // re-attempting to resolve the address." + Unreachable ) type timer struct { @@ -310,8 +322,8 @@ func (e *neighborEntry) setStateLocked(next NeighborState) { } if timedoutResolution || err != nil { - e.dispatchRemoveEventLocked() - e.setStateLocked(Failed) + e.setStateLocked(Unreachable) + e.dispatchChangeEventLocked() return } @@ -320,7 +332,7 @@ func (e *neighborEntry) setStateLocked(next NeighborState) { }), } - case Failed: + case Unreachable: e.notifyCompletionLocked(false /* succeeded */) case Unknown, Stale, Static: @@ -339,15 +351,19 @@ func (e *neighborEntry) setStateLocked(next NeighborState) { // Precondition: e.mu MUST be locked. func (e *neighborEntry) handlePacketQueuedLocked(localAddr tcpip.Address) { switch e.mu.neigh.State { - case Failed: - e.cache.nic.stats.Neighbor.FailedEntryLookups.Increment() - - fallthrough - case Unknown: + case Unknown, Unreachable: + prev := e.mu.neigh.State e.mu.neigh.State = Incomplete e.mu.neigh.UpdatedAtNanos = e.cache.nic.stack.clock.NowNanoseconds() - e.dispatchAddEventLocked() + switch prev { + case Unknown: + e.dispatchAddEventLocked() + case Unreachable: + e.dispatchChangeEventLocked() + e.cache.nic.stats.Neighbor.UnreachableEntryLookups.Increment() + } + config := e.nudState.Config() // Protected by e.mu. @@ -385,8 +401,8 @@ func (e *neighborEntry) handlePacketQueuedLocked(localAddr tcpip.Address) { } if timedoutResolution || err != nil { - e.dispatchRemoveEventLocked() - e.setStateLocked(Failed) + e.setStateLocked(Unreachable) + e.dispatchChangeEventLocked() return } @@ -418,7 +434,7 @@ func (e *neighborEntry) handleProbeLocked(remoteLinkAddr tcpip.LinkAddress) { // checks MUST be done by the NetworkEndpoint. switch e.mu.neigh.State { - case Unknown, Failed: + case Unknown: e.mu.neigh.LinkAddr = remoteLinkAddr e.setStateLocked(Stale) e.dispatchAddEventLocked() @@ -447,6 +463,13 @@ func (e *neighborEntry) handleProbeLocked(remoteLinkAddr tcpip.LinkAddress) { e.dispatchChangeEventLocked() } + case Unreachable: + // TODO(gvisor.dev/issue/5472): Do not change the entry if the link + // address is the same, as per RFC 7048. + e.mu.neigh.LinkAddr = remoteLinkAddr + e.setStateLocked(Stale) + e.dispatchChangeEventLocked() + case Static: // Do nothing @@ -549,7 +572,7 @@ func (e *neighborEntry) handleConfirmationLocked(linkAddr tcpip.LinkAddress, fla } e.mu.isRouter = flags.IsRouter - case Unknown, Failed, Static: + case Unknown, Unreachable, Static: // Do nothing default: @@ -571,7 +594,7 @@ func (e *neighborEntry) handleUpperLevelConfirmationLocked() { e.dispatchChangeEventLocked() } - case Unknown, Incomplete, Failed, Static: + case Unknown, Incomplete, Unreachable, Static: // Do nothing default: diff --git a/pkg/tcpip/stack/neighbor_entry_test.go b/pkg/tcpip/stack/neighbor_entry_test.go index f80d4ef8a..47a9e2448 100644 --- a/pkg/tcpip/stack/neighbor_entry_test.go +++ b/pkg/tcpip/stack/neighbor_entry_test.go @@ -70,38 +70,39 @@ func eventDiffOptsWithSort() []cmp.Option { } // The following unit tests exercise every state transition and verify its -// behavior with RFC 4681. +// behavior with RFC 4681 and RFC 7048. // -// | From | To | Cause | Update | Action | Event | -// | ========== | ========== | ========================================== | ======== | ===========| ======= | -// | Unknown | Unknown | Confirmation w/ unknown address | | | Added | -// | Unknown | Incomplete | Packet queued to unknown address | | Send probe | Added | -// | Unknown | Stale | Probe | | | Added | -// | Incomplete | Incomplete | Retransmit timer expired | | Send probe | Changed | -// | Incomplete | Reachable | Solicited confirmation | LinkAddr | Notify | Changed | -// | Incomplete | Stale | Unsolicited confirmation | LinkAddr | Notify | Changed | -// | Incomplete | Stale | Probe | LinkAddr | Notify | Changed | -// | Incomplete | Failed | Max probes sent without reply | | Notify | Removed | -// | Reachable | Reachable | Confirmation w/ different isRouter flag | IsRouter | | | -// | Reachable | Stale | Reachable timer expired | | | Changed | -// | Reachable | Stale | Probe or confirmation w/ different address | | | Changed | -// | Stale | Reachable | Solicited override confirmation | LinkAddr | | Changed | -// | Stale | Reachable | Solicited confirmation w/o address | | Notify | Changed | -// | Stale | Stale | Override confirmation | LinkAddr | | Changed | -// | Stale | Stale | Probe w/ different address | LinkAddr | | Changed | -// | Stale | Delay | Packet sent | | | Changed | -// | Delay | Reachable | Upper-layer confirmation | | | Changed | -// | Delay | Reachable | Solicited override confirmation | LinkAddr | | Changed | -// | Delay | Reachable | Solicited confirmation w/o address | | Notify | Changed | -// | Delay | Stale | Probe or confirmation w/ different address | | | Changed | -// | Delay | Probe | Delay timer expired | | Send probe | Changed | -// | Probe | Reachable | Solicited override confirmation | LinkAddr | | Changed | -// | Probe | Reachable | Solicited confirmation w/ same address | | Notify | Changed | -// | Probe | Reachable | Solicited confirmation w/o address | | Notify | Changed | -// | Probe | Stale | Probe or confirmation w/ different address | | | Changed | -// | Probe | Probe | Retransmit timer expired | | | Changed | -// | Probe | Failed | Max probes sent without reply | | Notify | Removed | -// | Failed | Incomplete | Packet queued | | Send probe | Added | +// | From | To | Cause | Update | Action | Event | +// | =========== | =========== | ========================================== | ======== | ===========| ======= | +// | Unknown | Unknown | Confirmation w/ unknown address | | | Added | +// | Unknown | Incomplete | Packet queued to unknown address | | Send probe | Added | +// | Unknown | Stale | Probe | | | Added | +// | Incomplete | Incomplete | Retransmit timer expired | | Send probe | Changed | +// | Incomplete | Reachable | Solicited confirmation | LinkAddr | Notify | Changed | +// | Incomplete | Stale | Unsolicited confirmation | LinkAddr | Notify | Changed | +// | Incomplete | Stale | Probe | LinkAddr | Notify | Changed | +// | Incomplete | Unreachable | Max probes sent without reply | | Notify | Changed | +// | Reachable | Reachable | Confirmation w/ different isRouter flag | IsRouter | | | +// | Reachable | Stale | Reachable timer expired | | | Changed | +// | Reachable | Stale | Probe or confirmation w/ different address | | | Changed | +// | Stale | Reachable | Solicited override confirmation | LinkAddr | | Changed | +// | Stale | Reachable | Solicited confirmation w/o address | | Notify | Changed | +// | Stale | Stale | Override confirmation | LinkAddr | | Changed | +// | Stale | Stale | Probe w/ different address | LinkAddr | | Changed | +// | Stale | Delay | Packet sent | | | Changed | +// | Delay | Reachable | Upper-layer confirmation | | | Changed | +// | Delay | Reachable | Solicited override confirmation | LinkAddr | | Changed | +// | Delay | Reachable | Solicited confirmation w/o address | | Notify | Changed | +// | Delay | Stale | Probe or confirmation w/ different address | | | Changed | +// | Delay | Probe | Delay timer expired | | Send probe | Changed | +// | Probe | Reachable | Solicited override confirmation | LinkAddr | | Changed | +// | Probe | Reachable | Solicited confirmation w/ same address | | Notify | Changed | +// | Probe | Reachable | Solicited confirmation w/o address | | Notify | Changed | +// | Probe | Stale | Probe or confirmation w/ different address | | | Changed | +// | Probe | Probe | Retransmit timer expired | | | Changed | +// | Probe | Unreachable | Max probes sent without reply | | Notify | Changed | +// | Unreachable | Incomplete | Packet queued | | Send probe | Changed | +// | Unreachable | Stale | Probe w/ different address | LinkAddr | | Changed | type testEntryEventType uint8 @@ -448,7 +449,7 @@ func TestEntryIncompleteToIncompleteDoesNotChangeUpdatedAt(t *testing.T) { clock.Advance(c.RetransmitTimer) // UpdatedAt should change after failing address resolution. Timing out after - // sending the last probe transitions the entry to Failed. + // sending the last probe transitions the entry to Unreachable. { wantProbes := []entryTestProbeInfo{ { @@ -478,12 +479,12 @@ func TestEntryIncompleteToIncompleteDoesNotChangeUpdatedAt(t *testing.T) { }, }, { - EventType: entryTestRemoved, + EventType: entryTestChanged, NICID: entryTestNICID, Entry: NeighborEntry{ Addr: entryTestAddr1, LinkAddr: tcpip.LinkAddress(""), - State: Incomplete, + State: Unreachable, }, }, } @@ -755,7 +756,7 @@ func TestEntryIncompleteToStaleWhenProbe(t *testing.T) { nudDisp.mu.Unlock() } -func TestEntryIncompleteToFailed(t *testing.T) { +func TestEntryIncompleteToUnreachable(t *testing.T) { c := DefaultNUDConfigurations() c.MaxMulticastProbes = 3 e, nudDisp, linkRes, clock := entryTestSetup(c) @@ -807,12 +808,12 @@ func TestEntryIncompleteToFailed(t *testing.T) { }, }, { - EventType: entryTestRemoved, + EventType: entryTestChanged, NICID: entryTestNICID, Entry: NeighborEntry{ Addr: entryTestAddr1, LinkAddr: tcpip.LinkAddress(""), - State: Incomplete, + State: Unreachable, }, }, } @@ -823,8 +824,8 @@ func TestEntryIncompleteToFailed(t *testing.T) { nudDisp.mu.Unlock() e.mu.Lock() - if e.mu.neigh.State != Failed { - t.Errorf("got e.mu.neigh.State = %q, want = %q", e.mu.neigh.State, Failed) + if e.mu.neigh.State != Unreachable { + t.Errorf("got e.mu.neigh.State = %q, want = %q", e.mu.neigh.State, Unreachable) } e.mu.Unlock() } @@ -3294,7 +3295,7 @@ func TestEntryProbeToReachableWhenSolicitedConfirmationWithoutAddress(t *testing nudDisp.mu.Unlock() } -func TestEntryProbeToFailed(t *testing.T) { +func TestEntryProbeToUnreachable(t *testing.T) { c := DefaultNUDConfigurations() c.MaxMulticastProbes = 3 c.MaxUnicastProbes = 3 @@ -3355,11 +3356,11 @@ func TestEntryProbeToFailed(t *testing.T) { e.mu.Unlock() } - // Wait for the last probe to expire, causing a transition to Failed. + // Wait for the last probe to expire, causing a transition to Unreachable. clock.Advance(c.RetransmitTimer) e.mu.Lock() - if e.mu.neigh.State != Failed { - t.Errorf("got e.mu.neigh.State = %q, want = %q", e.mu.neigh.State, Failed) + if e.mu.neigh.State != Unreachable { + t.Errorf("got e.mu.neigh.State = %q, want = %q", e.mu.neigh.State, Unreachable) } e.mu.Unlock() @@ -3401,12 +3402,12 @@ func TestEntryProbeToFailed(t *testing.T) { }, }, { - EventType: entryTestRemoved, + EventType: entryTestChanged, NICID: entryTestNICID, Entry: NeighborEntry{ Addr: entryTestAddr1, LinkAddr: entryTestLinkAddr1, - State: Probe, + State: Unreachable, }, }, } @@ -3417,7 +3418,7 @@ func TestEntryProbeToFailed(t *testing.T) { nudDisp.mu.Unlock() } -func TestEntryFailedToIncomplete(t *testing.T) { +func TestEntryUnreachableToIncomplete(t *testing.T) { c := DefaultNUDConfigurations() c.MaxMulticastProbes = 3 e, nudDisp, linkRes, clock := entryTestSetup(c) @@ -3461,8 +3462,8 @@ func TestEntryFailedToIncomplete(t *testing.T) { } e.mu.Lock() - if e.mu.neigh.State != Failed { - t.Errorf("got e.mu.neigh.State = %q, want = %q", e.mu.neigh.State, Failed) + if e.mu.neigh.State != Unreachable { + t.Errorf("got e.mu.neigh.State = %q, want = %q", e.mu.neigh.State, Unreachable) } e.mu.Unlock() @@ -3484,7 +3485,16 @@ func TestEntryFailedToIncomplete(t *testing.T) { }, }, { - EventType: entryTestRemoved, + EventType: entryTestChanged, + NICID: entryTestNICID, + Entry: NeighborEntry{ + Addr: entryTestAddr1, + LinkAddr: tcpip.LinkAddress(""), + State: Unreachable, + }, + }, + { + EventType: entryTestChanged, NICID: entryTestNICID, Entry: NeighborEntry{ Addr: entryTestAddr1, @@ -3492,6 +3502,72 @@ func TestEntryFailedToIncomplete(t *testing.T) { State: Incomplete, }, }, + } + nudDisp.mu.Lock() + if diff := cmp.Diff(wantEvents, nudDisp.events, eventDiffOpts()...); diff != "" { + t.Errorf("nud dispatcher events mismatch (-want, +got):\n%s", diff) + } + nudDisp.mu.Unlock() +} + +func TestEntryUnreachableToStale(t *testing.T) { + wantProbes := []entryTestProbeInfo{ + // The Incomplete-to-Incomplete state transition is tested here by + // verifying that 3 reachability probes were sent. + { + RemoteAddress: entryTestAddr1, + RemoteLinkAddress: tcpip.LinkAddress(""), + LocalAddress: entryTestAddr2, + }, + { + RemoteAddress: entryTestAddr1, + RemoteLinkAddress: tcpip.LinkAddress(""), + LocalAddress: entryTestAddr2, + }, + { + RemoteAddress: entryTestAddr1, + RemoteLinkAddress: tcpip.LinkAddress(""), + LocalAddress: entryTestAddr2, + }, + } + + c := DefaultNUDConfigurations() + c.MaxMulticastProbes = uint32(len(wantProbes)) + e, nudDisp, linkRes, clock := entryTestSetup(c) + + // TODO(gvisor.dev/issue/4872): Use helper functions to start entry tests in + // their expected state. + e.mu.Lock() + e.handlePacketQueuedLocked(entryTestAddr2) + if e.mu.neigh.State != Incomplete { + t.Errorf("got e.mu.neigh.State = %q, want = %q", e.mu.neigh.State, Incomplete) + } + e.mu.Unlock() + + waitFor := c.RetransmitTimer * time.Duration(c.MaxMulticastProbes) + clock.Advance(waitFor) + + linkRes.mu.Lock() + diff := cmp.Diff(wantProbes, linkRes.probes) + linkRes.mu.Unlock() + if diff != "" { + t.Fatalf("link address resolver probes mismatch (-want, +got):\n%s", diff) + } + + e.mu.Lock() + if e.mu.neigh.State != Unreachable { + t.Errorf("got e.mu.neigh.State = %q, want = %q", e.mu.neigh.State, Unreachable) + } + e.mu.Unlock() + + e.mu.Lock() + e.handleProbeLocked(entryTestLinkAddr2) + if e.mu.neigh.State != Stale { + t.Errorf("got e.mu.neigh.State = %q, want = %q", e.mu.neigh.State, Stale) + } + e.mu.Unlock() + + wantEvents := []testEntryEventInfo{ { EventType: entryTestAdded, NICID: entryTestNICID, @@ -3501,6 +3577,24 @@ func TestEntryFailedToIncomplete(t *testing.T) { State: Incomplete, }, }, + { + EventType: entryTestChanged, + NICID: entryTestNICID, + Entry: NeighborEntry{ + Addr: entryTestAddr1, + LinkAddr: tcpip.LinkAddress(""), + State: Unreachable, + }, + }, + { + EventType: entryTestChanged, + NICID: entryTestNICID, + Entry: NeighborEntry{ + Addr: entryTestAddr1, + LinkAddr: entryTestLinkAddr2, + State: Stale, + }, + }, } nudDisp.mu.Lock() if diff := cmp.Diff(wantEvents, nudDisp.events, eventDiffOpts()...); diff != "" { diff --git a/pkg/tcpip/stack/neighborstate_string.go b/pkg/tcpip/stack/neighborstate_string.go index aa7311ec6..765df4d7a 100644 --- a/pkg/tcpip/stack/neighborstate_string.go +++ b/pkg/tcpip/stack/neighborstate_string.go @@ -1,4 +1,4 @@ -// Copyright 2020 The gVisor Authors. +// Copyright 2021 The gVisor Authors. // // Licensed under the Apache License, Version 2.0 (the "License"); // you may not use this file except in compliance with the License. @@ -30,11 +30,12 @@ func _() { _ = x[Probe-5] _ = x[Static-6] _ = x[Failed-7] + _ = x[Unreachable-8] } -const _NeighborState_name = "UnknownIncompleteReachableStaleDelayProbeStaticFailed" +const _NeighborState_name = "UnknownIncompleteReachableStaleDelayProbeStaticFailedUnreachable" -var _NeighborState_index = [...]uint8{0, 7, 17, 26, 31, 36, 41, 47, 53} +var _NeighborState_index = [...]uint8{0, 7, 17, 26, 31, 36, 41, 47, 53, 64} func (i NeighborState) String() string { if i >= NeighborState(len(_NeighborState_index)-1) { |