diff options
Diffstat (limited to 'pkg/tcpip/stack/ndp.go')
-rw-r--r-- | pkg/tcpip/stack/ndp.go | 280 |
1 files changed, 160 insertions, 120 deletions
diff --git a/pkg/tcpip/stack/ndp.go b/pkg/tcpip/stack/ndp.go index 526c7d6ff..93567806b 100644 --- a/pkg/tcpip/stack/ndp.go +++ b/pkg/tcpip/stack/ndp.go @@ -33,12 +33,6 @@ const ( // Default = 1 (from RFC 4862 section 5.1) defaultDupAddrDetectTransmits = 1 - // defaultRetransmitTimer is the default amount of time to wait between - // sending NDP Neighbor solicitation messages. - // - // Default = 1s (from RFC 4861 section 10). - defaultRetransmitTimer = time.Second - // defaultMaxRtrSolicitations is the default number of Router // Solicitation messages to send when a NIC becomes enabled. // @@ -79,16 +73,6 @@ const ( // Default = true. defaultAutoGenGlobalAddresses = true - // minimumRetransmitTimer is the minimum amount of time to wait between - // sending NDP Neighbor solicitation messages. Note, RFC 4861 does - // not impose a minimum Retransmit Timer, but we do here to make sure - // the messages are not sent all at once. We also come to this value - // because in the RetransmitTimer field of a Router Advertisement, a - // value of 0 means unspecified, so the smallest valid value is 1. - // Note, the unit of the RetransmitTimer field in the Router - // Advertisement is milliseconds. - minimumRetransmitTimer = time.Millisecond - // minimumRtrSolicitationInterval is the minimum amount of time to wait // between sending Router Solicitation messages. This limit is imposed // to make sure that Router Solicitation messages are not sent all at @@ -467,8 +451,17 @@ type ndpState struct { // The default routers discovered through Router Advertisements. defaultRouters map[tcpip.Address]defaultRouterState - // The timer used to send the next router solicitation message. - rtrSolicitTimer *time.Timer + rtrSolicit struct { + // The timer used to send the next router solicitation message. + timer tcpip.Timer + + // Used to let the Router Solicitation timer know that it has been stopped. + // + // Must only be read from or written to while protected by the lock of + // the NIC this ndpState is associated with. MUST be set when the timer is + // set. + done *bool + } // The on-link prefixes discovered through Router Advertisements' Prefix // Information option. @@ -494,7 +487,7 @@ type ndpState struct { // to the DAD goroutine that DAD should stop. type dadState struct { // The DAD timer to send the next NS message, or resolve the address. - timer *time.Timer + timer tcpip.Timer // Used to let the DAD timer know that it has been stopped. // @@ -506,38 +499,38 @@ type dadState struct { // defaultRouterState holds data associated with a default router discovered by // a Router Advertisement (RA). type defaultRouterState struct { - // Timer to invalidate the default router. + // Job to invalidate the default router. // // Must not be nil. - invalidationTimer *tcpip.CancellableTimer + invalidationJob *tcpip.Job } // onLinkPrefixState holds data associated with an on-link prefix discovered by // a Router Advertisement's Prefix Information option (PI) when the NDP // configurations was configured to do so. type onLinkPrefixState struct { - // Timer to invalidate the on-link prefix. + // Job to invalidate the on-link prefix. // // Must not be nil. - invalidationTimer *tcpip.CancellableTimer + invalidationJob *tcpip.Job } // tempSLAACAddrState holds state associated with a temporary SLAAC address. type tempSLAACAddrState struct { - // Timer to deprecate the temporary SLAAC address. + // Job to deprecate the temporary SLAAC address. // // Must not be nil. - deprecationTimer *tcpip.CancellableTimer + deprecationJob *tcpip.Job - // Timer to invalidate the temporary SLAAC address. + // Job to invalidate the temporary SLAAC address. // // Must not be nil. - invalidationTimer *tcpip.CancellableTimer + invalidationJob *tcpip.Job - // Timer to regenerate the temporary SLAAC address. + // Job to regenerate the temporary SLAAC address. // // Must not be nil. - regenTimer *tcpip.CancellableTimer + regenJob *tcpip.Job createdAt time.Time @@ -552,15 +545,15 @@ type tempSLAACAddrState struct { // slaacPrefixState holds state associated with a SLAAC prefix. type slaacPrefixState struct { - // Timer to deprecate the prefix. + // Job to deprecate the prefix. // // Must not be nil. - deprecationTimer *tcpip.CancellableTimer + deprecationJob *tcpip.Job - // Timer to invalidate the prefix. + // Job to invalidate the prefix. // // Must not be nil. - invalidationTimer *tcpip.CancellableTimer + invalidationJob *tcpip.Job // Nonzero only when the address is not valid forever. validUntil time.Time @@ -642,19 +635,20 @@ func (ndp *ndpState) startDuplicateAddressDetection(addr tcpip.Address, ref *ref } var done bool - var timer *time.Timer + var timer tcpip.Timer // We initially start a timer to fire immediately because some of the DAD work // cannot be done while holding the NIC's lock. This is effectively the same // as starting a goroutine but we use a timer that fires immediately so we can // reset it for the next DAD iteration. - timer = time.AfterFunc(0, func() { - ndp.nic.mu.RLock() + timer = ndp.nic.stack.Clock().AfterFunc(0, func() { + ndp.nic.mu.Lock() + defer ndp.nic.mu.Unlock() + if done { // If we reach this point, it means that the DAD timer fired after // another goroutine already obtained the NIC lock and stopped DAD // before this function obtained the NIC lock. Simply return here and do // nothing further. - ndp.nic.mu.RUnlock() return } @@ -665,15 +659,23 @@ func (ndp *ndpState) startDuplicateAddressDetection(addr tcpip.Address, ref *ref } dadDone := remaining == 0 - ndp.nic.mu.RUnlock() var err *tcpip.Error if !dadDone { - err = ndp.sendDADPacket(addr) + // Use the unspecified address as the source address when performing DAD. + ref := ndp.nic.getRefOrCreateTempLocked(header.IPv6ProtocolNumber, header.IPv6Any, NeverPrimaryEndpoint) + + // Do not hold the lock when sending packets which may be a long running + // task or may block link address resolution. We know this is safe + // because immediately after obtaining the lock again, we check if DAD + // has been stopped before doing any work with the NIC. Note, DAD would be + // stopped if the NIC was disabled or removed, or if the address was + // removed. + ndp.nic.mu.Unlock() + err = ndp.sendDADPacket(addr, ref) + ndp.nic.mu.Lock() } - ndp.nic.mu.Lock() - defer ndp.nic.mu.Unlock() if done { // If we reach this point, it means that DAD was stopped after we released // the NIC's read lock and before we obtained the write lock. @@ -721,28 +723,39 @@ func (ndp *ndpState) startDuplicateAddressDetection(addr tcpip.Address, ref *ref // addr. // // addr must be a tentative IPv6 address on ndp's NIC. -func (ndp *ndpState) sendDADPacket(addr tcpip.Address) *tcpip.Error { +// +// The NIC ndp belongs to MUST NOT be locked. +func (ndp *ndpState) sendDADPacket(addr tcpip.Address, ref *referencedNetworkEndpoint) *tcpip.Error { snmc := header.SolicitedNodeAddr(addr) - // Use the unspecified address as the source address when performing DAD. - ref := ndp.nic.getRefOrCreateTemp(header.IPv6ProtocolNumber, header.IPv6Any, NeverPrimaryEndpoint, forceSpoofing) - r := makeRoute(header.IPv6ProtocolNumber, header.IPv6Any, snmc, ndp.nic.linkEP.LinkAddress(), ref, false, false) + r := makeRoute(header.IPv6ProtocolNumber, ref.ep.ID().LocalAddress, snmc, ndp.nic.linkEP.LinkAddress(), ref, false, false) defer r.Release() // Route should resolve immediately since snmc is a multicast address so a // remote link address can be calculated without a resolution process. if c, err := r.Resolve(nil); err != nil { + // Do not consider the NIC being unknown or disabled as a fatal error. + // Since this method is required to be called when the NIC is not locked, + // the NIC could have been disabled or removed by another goroutine. + if err == tcpip.ErrUnknownNICID || err != tcpip.ErrInvalidEndpointState { + return err + } + panic(fmt.Sprintf("ndp: error when resolving route to send NDP NS for DAD (%s -> %s on NIC(%d)): %s", header.IPv6Any, snmc, ndp.nic.ID(), err)) } else if c != nil { panic(fmt.Sprintf("ndp: route resolution not immediate for route to send NDP NS for DAD (%s -> %s on NIC(%d))", header.IPv6Any, snmc, ndp.nic.ID())) } - hdr := buffer.NewPrependable(int(r.MaxHeaderLength()) + header.ICMPv6NeighborSolicitMinimumSize) - pkt := header.ICMPv6(hdr.Prepend(header.ICMPv6NeighborSolicitMinimumSize)) - pkt.SetType(header.ICMPv6NeighborSolicit) - ns := header.NDPNeighborSolicit(pkt.NDPPayload()) + icmpData := header.ICMPv6(buffer.NewView(header.ICMPv6NeighborSolicitMinimumSize)) + icmpData.SetType(header.ICMPv6NeighborSolicit) + ns := header.NDPNeighborSolicit(icmpData.NDPPayload()) ns.SetTargetAddress(addr) - pkt.SetChecksum(header.ICMPv6Checksum(pkt, r.LocalAddress, r.RemoteAddress, buffer.VectorisedView{})) + icmpData.SetChecksum(header.ICMPv6Checksum(icmpData, r.LocalAddress, r.RemoteAddress, buffer.VectorisedView{})) + + pkt := NewPacketBuffer(PacketBufferOptions{ + ReserveHeaderBytes: int(r.MaxHeaderLength()), + Data: buffer.View(icmpData).ToVectorisedView(), + }) sent := r.Stats().ICMP.V6PacketsSent if err := r.WritePacket(nil, @@ -750,7 +763,7 @@ func (ndp *ndpState) sendDADPacket(addr tcpip.Address) *tcpip.Error { Protocol: header.ICMPv6ProtocolNumber, TTL: header.NDPHopLimit, TOS: DefaultTOS, - }, PacketBuffer{Header: hdr}, + }, pkt, ); err != nil { sent.Dropped.Increment() return err @@ -846,9 +859,9 @@ func (ndp *ndpState) handleRA(ip tcpip.Address, ra header.NDPRouterAdvert) { case ok && rl != 0: // This is an already discovered default router. Update - // the invalidation timer. - rtr.invalidationTimer.StopLocked() - rtr.invalidationTimer.Reset(rl) + // the invalidation job. + rtr.invalidationJob.Cancel() + rtr.invalidationJob.Schedule(rl) ndp.defaultRouters[ip] = rtr case ok && rl == 0: @@ -925,7 +938,7 @@ func (ndp *ndpState) invalidateDefaultRouter(ip tcpip.Address) { return } - rtr.invalidationTimer.StopLocked() + rtr.invalidationJob.Cancel() delete(ndp.defaultRouters, ip) // Let the integrator know a discovered default router is invalidated. @@ -954,12 +967,12 @@ func (ndp *ndpState) rememberDefaultRouter(ip tcpip.Address, rl time.Duration) { } state := defaultRouterState{ - invalidationTimer: tcpip.NewCancellableTimer(&ndp.nic.mu, func() { + invalidationJob: ndp.nic.stack.newJob(&ndp.nic.mu, func() { ndp.invalidateDefaultRouter(ip) }), } - state.invalidationTimer.Reset(rl) + state.invalidationJob.Schedule(rl) ndp.defaultRouters[ip] = state } @@ -984,13 +997,13 @@ func (ndp *ndpState) rememberOnLinkPrefix(prefix tcpip.Subnet, l time.Duration) } state := onLinkPrefixState{ - invalidationTimer: tcpip.NewCancellableTimer(&ndp.nic.mu, func() { + invalidationJob: ndp.nic.stack.newJob(&ndp.nic.mu, func() { ndp.invalidateOnLinkPrefix(prefix) }), } if l < header.NDPInfiniteLifetime { - state.invalidationTimer.Reset(l) + state.invalidationJob.Schedule(l) } ndp.onLinkPrefixes[prefix] = state @@ -1008,7 +1021,7 @@ func (ndp *ndpState) invalidateOnLinkPrefix(prefix tcpip.Subnet) { return } - s.invalidationTimer.StopLocked() + s.invalidationJob.Cancel() delete(ndp.onLinkPrefixes, prefix) // Let the integrator know a discovered on-link prefix is invalidated. @@ -1057,14 +1070,14 @@ func (ndp *ndpState) handleOnLinkPrefixInformation(pi header.NDPPrefixInformatio // This is an already discovered on-link prefix with a // new non-zero valid lifetime. // - // Update the invalidation timer. + // Update the invalidation job. - prefixState.invalidationTimer.StopLocked() + prefixState.invalidationJob.Cancel() if vl < header.NDPInfiniteLifetime { - // Prefix is valid for a finite lifetime, reset the timer to expire after + // Prefix is valid for a finite lifetime, schedule the job to execute after // the new valid lifetime. - prefixState.invalidationTimer.Reset(vl) + prefixState.invalidationJob.Schedule(vl) } ndp.onLinkPrefixes[prefix] = prefixState @@ -1129,7 +1142,7 @@ func (ndp *ndpState) doSLAAC(prefix tcpip.Subnet, pl, vl time.Duration) { } state := slaacPrefixState{ - deprecationTimer: tcpip.NewCancellableTimer(&ndp.nic.mu, func() { + deprecationJob: ndp.nic.stack.newJob(&ndp.nic.mu, func() { state, ok := ndp.slaacPrefixes[prefix] if !ok { panic(fmt.Sprintf("ndp: must have a slaacPrefixes entry for the deprecated SLAAC prefix %s", prefix)) @@ -1137,7 +1150,7 @@ func (ndp *ndpState) doSLAAC(prefix tcpip.Subnet, pl, vl time.Duration) { ndp.deprecateSLAACAddress(state.stableAddr.ref) }), - invalidationTimer: tcpip.NewCancellableTimer(&ndp.nic.mu, func() { + invalidationJob: ndp.nic.stack.newJob(&ndp.nic.mu, func() { state, ok := ndp.slaacPrefixes[prefix] if !ok { panic(fmt.Sprintf("ndp: must have a slaacPrefixes entry for the invalidated SLAAC prefix %s", prefix)) @@ -1159,19 +1172,19 @@ func (ndp *ndpState) doSLAAC(prefix tcpip.Subnet, pl, vl time.Duration) { if !ndp.generateSLAACAddr(prefix, &state) { // We were unable to generate an address for the prefix, we do not nothing - // further as there is no reason to maintain state or timers for a prefix we + // further as there is no reason to maintain state or jobs for a prefix we // do not have an address for. return } - // Setup the initial timers to deprecate and invalidate prefix. + // Setup the initial jobs to deprecate and invalidate prefix. if pl < header.NDPInfiniteLifetime && pl != 0 { - state.deprecationTimer.Reset(pl) + state.deprecationJob.Schedule(pl) } if vl < header.NDPInfiniteLifetime { - state.invalidationTimer.Reset(vl) + state.invalidationJob.Schedule(vl) state.validUntil = now.Add(vl) } @@ -1403,7 +1416,7 @@ func (ndp *ndpState) generateTempSLAACAddr(prefix tcpip.Subnet, prefixState *sla } state := tempSLAACAddrState{ - deprecationTimer: tcpip.NewCancellableTimer(&ndp.nic.mu, func() { + deprecationJob: ndp.nic.stack.newJob(&ndp.nic.mu, func() { prefixState, ok := ndp.slaacPrefixes[prefix] if !ok { panic(fmt.Sprintf("ndp: must have a slaacPrefixes entry for %s to deprecate temporary address %s", prefix, generatedAddr)) @@ -1416,7 +1429,7 @@ func (ndp *ndpState) generateTempSLAACAddr(prefix tcpip.Subnet, prefixState *sla ndp.deprecateSLAACAddress(tempAddrState.ref) }), - invalidationTimer: tcpip.NewCancellableTimer(&ndp.nic.mu, func() { + invalidationJob: ndp.nic.stack.newJob(&ndp.nic.mu, func() { prefixState, ok := ndp.slaacPrefixes[prefix] if !ok { panic(fmt.Sprintf("ndp: must have a slaacPrefixes entry for %s to invalidate temporary address %s", prefix, generatedAddr)) @@ -1429,7 +1442,7 @@ func (ndp *ndpState) generateTempSLAACAddr(prefix tcpip.Subnet, prefixState *sla ndp.invalidateTempSLAACAddr(prefixState.tempAddrs, generatedAddr.Address, tempAddrState) }), - regenTimer: tcpip.NewCancellableTimer(&ndp.nic.mu, func() { + regenJob: ndp.nic.stack.newJob(&ndp.nic.mu, func() { prefixState, ok := ndp.slaacPrefixes[prefix] if !ok { panic(fmt.Sprintf("ndp: must have a slaacPrefixes entry for %s to regenerate temporary address after %s", prefix, generatedAddr)) @@ -1456,9 +1469,9 @@ func (ndp *ndpState) generateTempSLAACAddr(prefix tcpip.Subnet, prefixState *sla ref: ref, } - state.deprecationTimer.Reset(pl) - state.invalidationTimer.Reset(vl) - state.regenTimer.Reset(pl - ndp.configs.RegenAdvanceDuration) + state.deprecationJob.Schedule(pl) + state.invalidationJob.Schedule(vl) + state.regenJob.Schedule(pl - ndp.configs.RegenAdvanceDuration) prefixState.generationAttempts++ prefixState.tempAddrs[generatedAddr.Address] = state @@ -1493,16 +1506,16 @@ func (ndp *ndpState) refreshSLAACPrefixLifetimes(prefix tcpip.Subnet, prefixStat prefixState.stableAddr.ref.deprecated = false } - // If prefix was preferred for some finite lifetime before, stop the - // deprecation timer so it can be reset. - prefixState.deprecationTimer.StopLocked() + // If prefix was preferred for some finite lifetime before, cancel the + // deprecation job so it can be reset. + prefixState.deprecationJob.Cancel() now := time.Now() - // Reset the deprecation timer if prefix has a finite preferred lifetime. + // Schedule the deprecation job if prefix has a finite preferred lifetime. if pl < header.NDPInfiniteLifetime { if !deprecated { - prefixState.deprecationTimer.Reset(pl) + prefixState.deprecationJob.Schedule(pl) } prefixState.preferredUntil = now.Add(pl) } else { @@ -1521,9 +1534,9 @@ func (ndp *ndpState) refreshSLAACPrefixLifetimes(prefix tcpip.Subnet, prefixStat // 3) Otherwise, reset the valid lifetime of the prefix to 2 hours. if vl >= header.NDPInfiniteLifetime { - // Handle the infinite valid lifetime separately as we do not keep a timer - // in this case. - prefixState.invalidationTimer.StopLocked() + // Handle the infinite valid lifetime separately as we do not schedule a + // job in this case. + prefixState.invalidationJob.Cancel() prefixState.validUntil = time.Time{} } else { var effectiveVl time.Duration @@ -1544,8 +1557,8 @@ func (ndp *ndpState) refreshSLAACPrefixLifetimes(prefix tcpip.Subnet, prefixStat } if effectiveVl != 0 { - prefixState.invalidationTimer.StopLocked() - prefixState.invalidationTimer.Reset(effectiveVl) + prefixState.invalidationJob.Cancel() + prefixState.invalidationJob.Schedule(effectiveVl) prefixState.validUntil = now.Add(effectiveVl) } } @@ -1557,7 +1570,7 @@ func (ndp *ndpState) refreshSLAACPrefixLifetimes(prefix tcpip.Subnet, prefixStat } // Note, we do not need to update the entries in the temporary address map - // after updating the timers because the timers are held as pointers. + // after updating the jobs because the jobs are held as pointers. var regenForAddr tcpip.Address allAddressesRegenerated := true for tempAddr, tempAddrState := range prefixState.tempAddrs { @@ -1571,14 +1584,14 @@ func (ndp *ndpState) refreshSLAACPrefixLifetimes(prefix tcpip.Subnet, prefixStat } // If the address is no longer valid, invalidate it immediately. Otherwise, - // reset the invalidation timer. + // reset the invalidation job. newValidLifetime := validUntil.Sub(now) if newValidLifetime <= 0 { ndp.invalidateTempSLAACAddr(prefixState.tempAddrs, tempAddr, tempAddrState) continue } - tempAddrState.invalidationTimer.StopLocked() - tempAddrState.invalidationTimer.Reset(newValidLifetime) + tempAddrState.invalidationJob.Cancel() + tempAddrState.invalidationJob.Schedule(newValidLifetime) // As per RFC 4941 section 3.3 step 4, the preferred lifetime of a temporary // address is the lower of the preferred lifetime of the stable address or @@ -1591,17 +1604,17 @@ func (ndp *ndpState) refreshSLAACPrefixLifetimes(prefix tcpip.Subnet, prefixStat } // If the address is no longer preferred, deprecate it immediately. - // Otherwise, reset the deprecation timer. + // Otherwise, schedule the deprecation job again. newPreferredLifetime := preferredUntil.Sub(now) - tempAddrState.deprecationTimer.StopLocked() + tempAddrState.deprecationJob.Cancel() if newPreferredLifetime <= 0 { ndp.deprecateSLAACAddress(tempAddrState.ref) } else { tempAddrState.ref.deprecated = false - tempAddrState.deprecationTimer.Reset(newPreferredLifetime) + tempAddrState.deprecationJob.Schedule(newPreferredLifetime) } - tempAddrState.regenTimer.StopLocked() + tempAddrState.regenJob.Cancel() if tempAddrState.regenerated { } else { allAddressesRegenerated = false @@ -1612,7 +1625,7 @@ func (ndp *ndpState) refreshSLAACPrefixLifetimes(prefix tcpip.Subnet, prefixStat // immediately after we finish iterating over the temporary addresses. regenForAddr = tempAddr } else { - tempAddrState.regenTimer.Reset(newPreferredLifetime - ndp.configs.RegenAdvanceDuration) + tempAddrState.regenJob.Schedule(newPreferredLifetime - ndp.configs.RegenAdvanceDuration) } } } @@ -1692,7 +1705,7 @@ func (ndp *ndpState) cleanupSLAACAddrResourcesAndNotify(addr tcpip.AddressWithPr ndp.cleanupSLAACPrefixResources(prefix, state) } -// cleanupSLAACPrefixResources cleansup a SLAAC prefix's timers and entry. +// cleanupSLAACPrefixResources cleans up a SLAAC prefix's jobs and entry. // // Panics if the SLAAC prefix is not known. // @@ -1704,8 +1717,8 @@ func (ndp *ndpState) cleanupSLAACPrefixResources(prefix tcpip.Subnet, state slaa } state.stableAddr.ref = nil - state.deprecationTimer.StopLocked() - state.invalidationTimer.StopLocked() + state.deprecationJob.Cancel() + state.invalidationJob.Cancel() delete(ndp.slaacPrefixes, prefix) } @@ -1750,13 +1763,13 @@ func (ndp *ndpState) cleanupTempSLAACAddrResourcesAndNotify(addr tcpip.AddressWi } // cleanupTempSLAACAddrResourcesAndNotify cleans up a temporary SLAAC address's -// timers and entry. +// jobs and entry. // // The NIC that ndp belongs to MUST be locked. func (ndp *ndpState) cleanupTempSLAACAddrResources(tempAddrs map[tcpip.Address]tempSLAACAddrState, tempAddr tcpip.Address, tempAddrState tempSLAACAddrState) { - tempAddrState.deprecationTimer.StopLocked() - tempAddrState.invalidationTimer.StopLocked() - tempAddrState.regenTimer.StopLocked() + tempAddrState.deprecationJob.Cancel() + tempAddrState.invalidationJob.Cancel() + tempAddrState.regenJob.Cancel() delete(tempAddrs, tempAddr) } @@ -1816,7 +1829,7 @@ func (ndp *ndpState) cleanupState(hostOnly bool) { // // The NIC ndp belongs to MUST be locked. func (ndp *ndpState) startSolicitingRouters() { - if ndp.rtrSolicitTimer != nil { + if ndp.rtrSolicit.timer != nil { // We are already soliciting routers. return } @@ -1833,14 +1846,27 @@ func (ndp *ndpState) startSolicitingRouters() { delay = time.Duration(rand.Int63n(int64(ndp.configs.MaxRtrSolicitationDelay))) } - ndp.rtrSolicitTimer = time.AfterFunc(delay, func() { + var done bool + ndp.rtrSolicit.done = &done + ndp.rtrSolicit.timer = ndp.nic.stack.Clock().AfterFunc(delay, func() { + ndp.nic.mu.Lock() + if done { + // If we reach this point, it means that the RS timer fired after another + // goroutine already obtained the NIC lock and stopped solicitations. + // Simply return here and do nothing further. + ndp.nic.mu.Unlock() + return + } + // As per RFC 4861 section 4.1, the source of the RS is an address assigned // to the sending interface, or the unspecified address if no address is // assigned to the sending interface. - ref := ndp.nic.primaryIPv6Endpoint(header.IPv6AllRoutersMulticastAddress) + ref := ndp.nic.primaryIPv6EndpointRLocked(header.IPv6AllRoutersMulticastAddress) if ref == nil { - ref = ndp.nic.getRefOrCreateTemp(header.IPv6ProtocolNumber, header.IPv6Any, NeverPrimaryEndpoint, forceSpoofing) + ref = ndp.nic.getRefOrCreateTempLocked(header.IPv6ProtocolNumber, header.IPv6Any, NeverPrimaryEndpoint) } + ndp.nic.mu.Unlock() + localAddr := ref.ep.ID().LocalAddress r := makeRoute(header.IPv6ProtocolNumber, localAddr, header.IPv6AllRoutersMulticastAddress, ndp.nic.linkEP.LinkAddress(), ref, false, false) defer r.Release() @@ -1849,6 +1875,13 @@ func (ndp *ndpState) startSolicitingRouters() { // header.IPv6AllRoutersMulticastAddress is a multicast address so a // remote link address can be calculated without a resolution process. if c, err := r.Resolve(nil); err != nil { + // Do not consider the NIC being unknown or disabled as a fatal error. + // Since this method is required to be called when the NIC is not locked, + // the NIC could have been disabled or removed by another goroutine. + if err == tcpip.ErrUnknownNICID || err == tcpip.ErrInvalidEndpointState { + return + } + panic(fmt.Sprintf("ndp: error when resolving route to send NDP RS (%s -> %s on NIC(%d)): %s", header.IPv6Any, header.IPv6AllRoutersMulticastAddress, ndp.nic.ID(), err)) } else if c != nil { panic(fmt.Sprintf("ndp: route resolution not immediate for route to send NDP RS (%s -> %s on NIC(%d))", header.IPv6Any, header.IPv6AllRoutersMulticastAddress, ndp.nic.ID())) @@ -1868,12 +1901,16 @@ func (ndp *ndpState) startSolicitingRouters() { } } payloadSize := header.ICMPv6HeaderSize + header.NDPRSMinimumSize + int(optsSerializer.Length()) - hdr := buffer.NewPrependable(int(r.MaxHeaderLength()) + payloadSize) - pkt := header.ICMPv6(hdr.Prepend(payloadSize)) - pkt.SetType(header.ICMPv6RouterSolicit) - rs := header.NDPRouterSolicit(pkt.NDPPayload()) + icmpData := header.ICMPv6(buffer.NewView(payloadSize)) + icmpData.SetType(header.ICMPv6RouterSolicit) + rs := header.NDPRouterSolicit(icmpData.NDPPayload()) rs.Options().Serialize(optsSerializer) - pkt.SetChecksum(header.ICMPv6Checksum(pkt, r.LocalAddress, r.RemoteAddress, buffer.VectorisedView{})) + icmpData.SetChecksum(header.ICMPv6Checksum(icmpData, r.LocalAddress, r.RemoteAddress, buffer.VectorisedView{})) + + pkt := NewPacketBuffer(PacketBufferOptions{ + ReserveHeaderBytes: int(r.MaxHeaderLength()), + Data: buffer.View(icmpData).ToVectorisedView(), + }) sent := r.Stats().ICMP.V6PacketsSent if err := r.WritePacket(nil, @@ -1881,7 +1918,7 @@ func (ndp *ndpState) startSolicitingRouters() { Protocol: header.ICMPv6ProtocolNumber, TTL: header.NDPHopLimit, TOS: DefaultTOS, - }, PacketBuffer{Header: hdr}, + }, pkt, ); err != nil { sent.Dropped.Increment() log.Printf("startSolicitingRouters: error writing NDP router solicit message on NIC(%d); err = %s", ndp.nic.ID(), err) @@ -1893,17 +1930,18 @@ func (ndp *ndpState) startSolicitingRouters() { } ndp.nic.mu.Lock() - defer ndp.nic.mu.Unlock() - if remaining == 0 { - ndp.rtrSolicitTimer = nil - } else if ndp.rtrSolicitTimer != nil { + if done || remaining == 0 { + ndp.rtrSolicit.timer = nil + ndp.rtrSolicit.done = nil + } else if ndp.rtrSolicit.timer != nil { // Note, we need to explicitly check to make sure that // the timer field is not nil because if it was nil but // we still reached this point, then we know the NIC // was requested to stop soliciting routers so we don't // need to send the next Router Solicitation message. - ndp.rtrSolicitTimer.Reset(ndp.configs.RtrSolicitationInterval) + ndp.rtrSolicit.timer.Reset(ndp.configs.RtrSolicitationInterval) } + ndp.nic.mu.Unlock() }) } @@ -1913,13 +1951,15 @@ func (ndp *ndpState) startSolicitingRouters() { // // The NIC ndp belongs to MUST be locked. func (ndp *ndpState) stopSolicitingRouters() { - if ndp.rtrSolicitTimer == nil { + if ndp.rtrSolicit.timer == nil { // Nothing to do. return } - ndp.rtrSolicitTimer.Stop() - ndp.rtrSolicitTimer = nil + *ndp.rtrSolicit.done = true + ndp.rtrSolicit.timer.Stop() + ndp.rtrSolicit.timer = nil + ndp.rtrSolicit.done = nil } // initializeTempAddrState initializes state related to temporary SLAAC |