diff options
| -rw-r--r-- | pkg/tcpip/header/ipv6.go | 52 | ||||
| -rw-r--r-- | pkg/tcpip/stack/ndp.go | 645 | ||||
| -rw-r--r-- | pkg/tcpip/stack/ndp_test.go | 1089 | ||||
| -rw-r--r-- | pkg/tcpip/stack/nic.go | 34 | ||||
| -rw-r--r-- | pkg/tcpip/stack/stack.go | 20 |
5 files changed, 1571 insertions, 269 deletions
diff --git a/pkg/tcpip/header/ipv6.go b/pkg/tcpip/header/ipv6.go index ba80b64a8..4f367fe4c 100644 --- a/pkg/tcpip/header/ipv6.go +++ b/pkg/tcpip/header/ipv6.go @@ -17,6 +17,7 @@ package header import ( "crypto/sha256" "encoding/binary" + "fmt" "strings" "gvisor.dev/gvisor/pkg/tcpip" @@ -445,3 +446,54 @@ func ScopeForIPv6Address(addr tcpip.Address) (IPv6AddressScope, *tcpip.Error) { return GlobalScope, nil } } + +// InitialTempIID generates the initial temporary IID history value to generate +// temporary SLAAC addresses with. +// +// Panics if initialTempIIDHistory is not at least IIDSize bytes. +func InitialTempIID(initialTempIIDHistory []byte, seed []byte, nicID tcpip.NICID) { + h := sha256.New() + // h.Write never returns an error. + h.Write(seed) + var nicIDBuf [4]byte + binary.BigEndian.PutUint32(nicIDBuf[:], uint32(nicID)) + h.Write(nicIDBuf[:]) + + var sumBuf [sha256.Size]byte + sum := h.Sum(sumBuf[:0]) + + if n := copy(initialTempIIDHistory, sum[sha256.Size-IIDSize:]); n != IIDSize { + panic(fmt.Sprintf("copied %d bytes, expected %d bytes", n, IIDSize)) + } +} + +// GenerateTempIPv6SLAACAddr generates a temporary SLAAC IPv6 address for an +// associated stable/permanent SLAAC address. +// +// GenerateTempIPv6SLAACAddr will update the temporary IID history value to be +// used when generating a new temporary IID. +// +// Panics if tempIIDHistory is not at least IIDSize bytes. +func GenerateTempIPv6SLAACAddr(tempIIDHistory []byte, stableAddr tcpip.Address) tcpip.AddressWithPrefix { + addrBytes := []byte(stableAddr) + h := sha256.New() + h.Write(tempIIDHistory) + h.Write(addrBytes[IIDOffsetInIPv6Address:]) + var sumBuf [sha256.Size]byte + sum := h.Sum(sumBuf[:0]) + + // The rightmost 64 bits of sum are saved for the next iteration. + if n := copy(tempIIDHistory, sum[sha256.Size-IIDSize:]); n != IIDSize { + panic(fmt.Sprintf("copied %d bytes, expected %d bytes", n, IIDSize)) + } + + // The leftmost 64 bits of sum is used as the IID. + if n := copy(addrBytes[IIDOffsetInIPv6Address:], sum); n != IIDSize { + panic(fmt.Sprintf("copied %d IID bytes, expected %d bytes", n, IIDSize)) + } + + return tcpip.AddressWithPrefix{ + Address: tcpip.Address(addrBytes), + PrefixLen: IIDOffsetInIPv6Address * 8, + } +} diff --git a/pkg/tcpip/stack/ndp.go b/pkg/tcpip/stack/ndp.go index c11d62f97..fbc0e3f55 100644 --- a/pkg/tcpip/stack/ndp.go +++ b/pkg/tcpip/stack/ndp.go @@ -119,6 +119,32 @@ const ( // identifier (IID) is 64 bits and an IPv6 address is 128 bits, so // 128 - 64 = 64. validPrefixLenForAutoGen = 64 + + // defaultAutoGenTempGlobalAddresses is the default configuration for whether + // or not to generate temporary SLAAC addresses. + defaultAutoGenTempGlobalAddresses = true + + // defaultMaxTempAddrValidLifetime is the default maximum valid lifetime + // for temporary SLAAC addresses generated as part of RFC 4941. + // + // Default = 7 days (from RFC 4941 section 5). + defaultMaxTempAddrValidLifetime = 7 * 24 * time.Hour + + // defaultMaxTempAddrPreferredLifetime is the default preferred lifetime + // for temporary SLAAC addresses generated as part of RFC 4941. + // + // Default = 1 day (from RFC 4941 section 5). + defaultMaxTempAddrPreferredLifetime = 24 * time.Hour + + // defaultRegenAdvanceDuration is the default duration before the deprecation + // of a temporary address when a new address will be generated. + // + // Default = 5s (from RFC 4941 section 5). + defaultRegenAdvanceDuration = 5 * time.Second + + // minRegenAdvanceDuration is the minimum duration before the deprecation + // of a temporary address when a new address will be generated. + minRegenAdvanceDuration = time.Duration(0) ) var ( @@ -131,6 +157,37 @@ var ( // // Min = 2hrs. MinPrefixInformationValidLifetimeForUpdate = 2 * time.Hour + + // MaxDesyncFactor is the upper bound for the preferred lifetime's desync + // factor for temporary SLAAC addresses. + // + // This is exported as a variable (instead of a constant) so tests + // can update it to a smaller value. + // + // Must be greater than 0. + // + // Max = 10m (from RFC 4941 section 5). + MaxDesyncFactor = 10 * time.Minute + + // MinMaxTempAddrPreferredLifetime is the minimum value allowed for the + // maximum preferred lifetime for temporary SLAAC addresses. + // + // This is exported as a variable (instead of a constant) so tests + // can update it to a smaller value. + // + // This value guarantees that a temporary address will be preferred for at + // least 1hr if the SLAAC prefix is valid for at least that time. + MinMaxTempAddrPreferredLifetime = defaultRegenAdvanceDuration + MaxDesyncFactor + time.Hour + + // MinMaxTempAddrValidLifetime is the minimum value allowed for the + // maximum valid lifetime for temporary SLAAC addresses. + // + // This is exported as a variable (instead of a constant) so tests + // can update it to a smaller value. + // + // This value guarantees that a temporary address will be valid for at least + // 2hrs if the SLAAC prefix is valid for at least that time. + MinMaxTempAddrValidLifetime = 2 * time.Hour ) // DHCPv6ConfigurationFromNDPRA is a configuration available via DHCPv6 that an @@ -324,35 +381,49 @@ type NDPConfigurations struct { // alternative addresses (e.g. IIDs based on the modified EUI64 of a NIC's // MAC address), then no attempt will be made to resolve the conflict. AutoGenAddressConflictRetries uint8 + + // AutoGenTempGlobalAddresses determines whether or not temporary SLAAC + // addresses will be generated for a NIC as part of SLAAC privacy extensions, + // RFC 4941. + // + // Ignored if AutoGenGlobalAddresses is false. + AutoGenTempGlobalAddresses bool + + // MaxTempAddrValidLifetime is the maximum valid lifetime for temporary + // SLAAC addresses. + MaxTempAddrValidLifetime time.Duration + + // MaxTempAddrPreferredLifetime is the maximum preferred lifetime for + // temporary SLAAC addresses. + MaxTempAddrPreferredLifetime time.Duration + + // RegenAdvanceDuration is the duration before the deprecation of a temporary + // address when a new address will be generated. + RegenAdvanceDuration time.Duration } // DefaultNDPConfigurations returns an NDPConfigurations populated with // default values. func DefaultNDPConfigurations() NDPConfigurations { return NDPConfigurations{ - DupAddrDetectTransmits: defaultDupAddrDetectTransmits, - RetransmitTimer: defaultRetransmitTimer, - MaxRtrSolicitations: defaultMaxRtrSolicitations, - RtrSolicitationInterval: defaultRtrSolicitationInterval, - MaxRtrSolicitationDelay: defaultMaxRtrSolicitationDelay, - HandleRAs: defaultHandleRAs, - DiscoverDefaultRouters: defaultDiscoverDefaultRouters, - DiscoverOnLinkPrefixes: defaultDiscoverOnLinkPrefixes, - AutoGenGlobalAddresses: defaultAutoGenGlobalAddresses, + DupAddrDetectTransmits: defaultDupAddrDetectTransmits, + RetransmitTimer: defaultRetransmitTimer, + MaxRtrSolicitations: defaultMaxRtrSolicitations, + RtrSolicitationInterval: defaultRtrSolicitationInterval, + MaxRtrSolicitationDelay: defaultMaxRtrSolicitationDelay, + HandleRAs: defaultHandleRAs, + DiscoverDefaultRouters: defaultDiscoverDefaultRouters, + DiscoverOnLinkPrefixes: defaultDiscoverOnLinkPrefixes, + AutoGenGlobalAddresses: defaultAutoGenGlobalAddresses, + AutoGenTempGlobalAddresses: defaultAutoGenTempGlobalAddresses, + MaxTempAddrValidLifetime: defaultMaxTempAddrValidLifetime, + MaxTempAddrPreferredLifetime: defaultMaxTempAddrPreferredLifetime, + RegenAdvanceDuration: defaultRegenAdvanceDuration, } } // validate modifies an NDPConfigurations with valid values. If invalid values // are present in c, the corresponding default values will be used instead. -// -// If RetransmitTimer is less than minimumRetransmitTimer, then a value of -// defaultRetransmitTimer will be used. -// -// If RtrSolicitationInterval is less than minimumRtrSolicitationInterval, then -// a value of defaultRtrSolicitationInterval will be used. -// -// If MaxRtrSolicitationDelay is less than minimumMaxRtrSolicitationDelay, then -// a value of defaultMaxRtrSolicitationDelay will be used. func (c *NDPConfigurations) validate() { if c.RetransmitTimer < minimumRetransmitTimer { c.RetransmitTimer = defaultRetransmitTimer @@ -365,6 +436,18 @@ func (c *NDPConfigurations) validate() { if c.MaxRtrSolicitationDelay < minimumMaxRtrSolicitationDelay { c.MaxRtrSolicitationDelay = defaultMaxRtrSolicitationDelay } + + if c.MaxTempAddrValidLifetime < MinMaxTempAddrValidLifetime { + c.MaxTempAddrValidLifetime = MinMaxTempAddrValidLifetime + } + + if c.MaxTempAddrPreferredLifetime < MinMaxTempAddrPreferredLifetime || c.MaxTempAddrPreferredLifetime > c.MaxTempAddrValidLifetime { + c.MaxTempAddrPreferredLifetime = MinMaxTempAddrPreferredLifetime + } + + if c.RegenAdvanceDuration < minRegenAdvanceDuration { + c.RegenAdvanceDuration = minRegenAdvanceDuration + } } // ndpState is the per-interface NDP state. @@ -394,6 +477,14 @@ type ndpState struct { // The last learned DHCPv6 configuration from an NDP RA. dhcpv6Configuration DHCPv6ConfigurationFromNDPRA + + // temporaryIIDHistory is the history value used to generate a new temporary + // IID. + temporaryIIDHistory [header.IIDSize]byte + + // temporaryAddressDesyncFactor is the preferred lifetime's desync factor for + // temporary SLAAC addresses. + temporaryAddressDesyncFactor time.Duration } // dadState holds the Duplicate Address Detection timer and channel to signal @@ -414,7 +505,7 @@ type dadState struct { type defaultRouterState struct { // Timer to invalidate the default router. // - // May not be nil. + // Must not be nil. invalidationTimer *tcpip.CancellableTimer } @@ -424,20 +515,48 @@ type defaultRouterState struct { type onLinkPrefixState struct { // Timer to invalidate the on-link prefix. // - // May not be nil. + // Must not be nil. + invalidationTimer *tcpip.CancellableTimer +} + +// tempSLAACAddrState holds state associated with a temporary SLAAC address. +type tempSLAACAddrState struct { + // Timer to deprecate the temporary SLAAC address. + // + // Must not be nil. + deprecationTimer *tcpip.CancellableTimer + + // Timer to invalidate the temporary SLAAC address. + // + // Must not be nil. invalidationTimer *tcpip.CancellableTimer + + // Timer to regenerate the temporary SLAAC address. + // + // Must not be nil. + regenTimer *tcpip.CancellableTimer + + createdAt time.Time + + // The address's endpoint. + // + // Must not be nil. + ref *referencedNetworkEndpoint + + // Has a new temporary SLAAC address already been regenerated? + regenerated bool } // slaacPrefixState holds state associated with a SLAAC prefix. type slaacPrefixState struct { // Timer to deprecate the prefix. // - // May not be nil. + // Must not be nil. deprecationTimer *tcpip.CancellableTimer // Timer to invalidate the prefix. // - // May not be nil. + // Must not be nil. invalidationTimer *tcpip.CancellableTimer // Nonzero only when the address is not valid forever. @@ -446,19 +565,27 @@ type slaacPrefixState struct { // Nonzero only when the address is not preferred forever. preferredUntil time.Time - // The prefix's permanent address endpoint. + // The endpoint for the stable address generated for a SLAAC prefix. // // May only be nil when a SLAAC address is being (re-)generated. Otherwise, - // must not be nil as all SLAAC prefixes must have a SLAAC address. - ref *referencedNetworkEndpoint + // must not be nil as all SLAAC prefixes must have a stable address. + stableAddrRef *referencedNetworkEndpoint + + // The temporary (short-lived) addresses generated for the SLAAC prefix. + tempAddrs map[tcpip.Address]tempSLAACAddrState - // The number of times a permanent address has been generated for the prefix. + // The next two fields are used by both stable and temporary addresses + // generated for a SLAAC prefix. This is safe as only 1 address will be + // in the generation and DAD process at any time. That is, no two addresses + // will be generated at the same time for a given SLAAC prefix. + + // The number of times an address has been generated. // // Addresses may be regenerated in reseponse to a DAD conflicts. generationAttempts uint8 - // The maximum number of times to attempt regeneration of a permanent SLAAC - // address in response to DAD conflicts. + // The maximum number of times to attempt regeneration of a SLAAC address + // in response to DAD conflicts. maxGenerationAttempts uint8 } @@ -536,10 +663,10 @@ func (ndp *ndpState) startDuplicateAddressDetection(addr tcpip.Address, ref *ref } 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. - ndp.nic.mu.Unlock() return } @@ -551,8 +678,6 @@ func (ndp *ndpState) startDuplicateAddressDetection(addr tcpip.Address, ref *ref // schedule the next DAD timer. remaining-- timer.Reset(ndp.nic.stack.ndpConfigs.RetransmitTimer) - - ndp.nic.mu.Unlock() return } @@ -560,15 +685,18 @@ func (ndp *ndpState) startDuplicateAddressDetection(addr tcpip.Address, ref *ref // the last NDP NS. Either way, clean up addr's DAD state and let the // integrator know DAD has completed. delete(ndp.dad, addr) - ndp.nic.mu.Unlock() - - if err != nil { - log.Printf("ndpdad: error occured during DAD iteration for addr (%s) on NIC(%d); err = %s", addr, ndp.nic.ID(), err) - } if ndpDisp := ndp.nic.stack.ndpDisp; ndpDisp != nil { ndpDisp.OnDuplicateAddressDetectionStatus(ndp.nic.ID(), addr, dadDone, err) } + + // If DAD resolved for a stable SLAAC address, attempt generation of a + // temporary SLAAC address. + if dadDone && ref.configType == slaac { + // Reset the generation attempts counter as we are starting the generation + // of a new address for the SLAAC prefix. + ndp.regenerateTempSLAACAddr(ref.addrWithPrefix().Subnet(), true /* resetGenAttempts */) + } }) ndp.dad[addr] = dadState{ @@ -953,9 +1081,10 @@ func (ndp *ndpState) handleAutonomousPrefixInformation(pi header.NDPPrefixInform prefix := pi.Subnet() // Check if we already maintain SLAAC state for prefix. - if _, ok := ndp.slaacPrefixes[prefix]; ok { + if state, ok := ndp.slaacPrefixes[prefix]; ok { // As per RFC 4862 section 5.5.3.e, refresh prefix's SLAAC lifetimes. - ndp.refreshSLAACPrefixLifetimes(prefix, pl, vl) + ndp.refreshSLAACPrefixLifetimes(prefix, &state, pl, vl) + ndp.slaacPrefixes[prefix] = state return } @@ -996,7 +1125,7 @@ func (ndp *ndpState) doSLAAC(prefix tcpip.Subnet, pl, vl time.Duration) { panic(fmt.Sprintf("ndp: must have a slaacPrefixes entry for the deprecated SLAAC prefix %s", prefix)) } - ndp.deprecateSLAACAddress(state.ref) + ndp.deprecateSLAACAddress(state.stableAddrRef) }), invalidationTimer: tcpip.NewCancellableTimer(&ndp.nic.mu, func() { state, ok := ndp.slaacPrefixes[prefix] @@ -1006,6 +1135,7 @@ func (ndp *ndpState) doSLAAC(prefix tcpip.Subnet, pl, vl time.Duration) { ndp.invalidateSLAACPrefix(prefix, state) }), + tempAddrs: make(map[tcpip.Address]tempSLAACAddrState), maxGenerationAttempts: ndp.configs.AutoGenAddressConflictRetries + 1, } @@ -1035,9 +1165,49 @@ func (ndp *ndpState) doSLAAC(prefix tcpip.Subnet, pl, vl time.Duration) { state.validUntil = now.Add(vl) } + // If the address is assigned (DAD resolved), generate a temporary address. + if state.stableAddrRef.getKind() == permanent { + // Reset the generation attempts counter as we are starting the generation + // of a new address for the SLAAC prefix. + ndp.generateTempSLAACAddr(prefix, &state, true /* resetGenAttempts */) + } + ndp.slaacPrefixes[prefix] = state } +// addSLAACAddr adds a SLAAC address to the NIC. +// +// The NIC that ndp belongs to MUST be locked. +func (ndp *ndpState) addSLAACAddr(addr tcpip.AddressWithPrefix, configType networkEndpointConfigType, deprecated bool) *referencedNetworkEndpoint { + // If the nic already has this address, do nothing further. + if ndp.nic.hasPermanentAddrLocked(addr.Address) { + return nil + } + + // Inform the integrator that we have a new SLAAC address. + ndpDisp := ndp.nic.stack.ndpDisp + if ndpDisp == nil { + return nil + } + + if !ndpDisp.OnAutoGenAddress(ndp.nic.ID(), addr) { + // Informed by the integrator not to add the address. + return nil + } + + protocolAddr := tcpip.ProtocolAddress{ + Protocol: header.IPv6ProtocolNumber, + AddressWithPrefix: addr, + } + + ref, err := ndp.nic.addAddressLocked(protocolAddr, FirstPrimaryEndpoint, permanent, configType, deprecated) + if err != nil { + panic(fmt.Sprintf("ndp: error when adding SLAAC address %+v: %s", protocolAddr, err)) + } + + return ref +} + // generateSLAACAddr generates a SLAAC address for prefix. // // Returns true if an address was successfully generated. @@ -1046,7 +1216,7 @@ func (ndp *ndpState) doSLAAC(prefix tcpip.Subnet, pl, vl time.Duration) { // // The NIC that ndp belongs to MUST be locked. func (ndp *ndpState) generateSLAACAddr(prefix tcpip.Subnet, state *slaacPrefixState) bool { - if r := state.ref; r != nil { + if r := state.stableAddrRef; r != nil { panic(fmt.Sprintf("ndp: SLAAC prefix %s already has a permenant address %s", prefix, r.addrWithPrefix())) } @@ -1085,39 +1255,18 @@ func (ndp *ndpState) generateSLAACAddr(prefix tcpip.Subnet, state *slaacPrefixSt return false } - generatedAddr := tcpip.ProtocolAddress{ - Protocol: header.IPv6ProtocolNumber, - AddressWithPrefix: tcpip.AddressWithPrefix{ - Address: tcpip.Address(addrBytes), - PrefixLen: validPrefixLenForAutoGen, - }, - } - - // If the nic already has this address, do nothing further. - if ndp.nic.hasPermanentAddrLocked(generatedAddr.AddressWithPrefix.Address) { - return false - } - - // Inform the integrator that we have a new SLAAC address. - ndpDisp := ndp.nic.stack.ndpDisp - if ndpDisp == nil { - return false + generatedAddr := tcpip.AddressWithPrefix{ + Address: tcpip.Address(addrBytes), + PrefixLen: validPrefixLenForAutoGen, } - if !ndpDisp.OnAutoGenAddress(ndp.nic.ID(), generatedAddr.AddressWithPrefix) { - // Informed by the integrator not to add the address. - return false + if ref := ndp.addSLAACAddr(generatedAddr, slaac, time.Since(state.preferredUntil) >= 0 /* deprecated */); ref != nil { + state.stableAddrRef = ref + state.generationAttempts++ + return true } - deprecated := time.Since(state.preferredUntil) >= 0 - ref, err := ndp.nic.addAddressLocked(generatedAddr, FirstPrimaryEndpoint, permanent, slaac, deprecated) - if err != nil { - panic(fmt.Sprintf("ndp: error when adding address %+v: %s", generatedAddr, err)) - } - - state.generationAttempts++ - state.ref = ref - return true + return false } // regenerateSLAACAddr regenerates an address for a SLAAC prefix. @@ -1143,24 +1292,167 @@ func (ndp *ndpState) regenerateSLAACAddr(prefix tcpip.Subnet) { ndp.invalidateSLAACPrefix(prefix, state) } -// refreshSLAACPrefixLifetimes refreshes the lifetimes of a SLAAC prefix. +// generateTempSLAACAddr generates a new temporary SLAAC address. // -// pl is the new preferred lifetime. vl is the new valid lifetime. +// If resetGenAttempts is true, the prefix's generation counter will be reset. +// +// Returns true if a new address was generated. +func (ndp *ndpState) generateTempSLAACAddr(prefix tcpip.Subnet, prefixState *slaacPrefixState, resetGenAttempts bool) bool { + // Are we configured to auto-generate new temporary global addresses for the + // prefix? + if !ndp.configs.AutoGenTempGlobalAddresses || prefix == header.IPv6LinkLocalPrefix.Subnet() { + return false + } + + if resetGenAttempts { + prefixState.generationAttempts = 0 + prefixState.maxGenerationAttempts = ndp.configs.AutoGenAddressConflictRetries + 1 + } + + // If we have already reached the maximum address generation attempts for the + // prefix, do not generate another address. + if prefixState.generationAttempts == prefixState.maxGenerationAttempts { + return false + } + + stableAddr := prefixState.stableAddrRef.ep.ID().LocalAddress + now := time.Now() + + // As per RFC 4941 section 3.3 step 4, the valid lifetime of a temporary + // address is the lower of the valid lifetime of the stable address or the + // maximum temporary address valid lifetime. + vl := ndp.configs.MaxTempAddrValidLifetime + if prefixState.validUntil != (time.Time{}) { + if prefixVL := prefixState.validUntil.Sub(now); vl > prefixVL { + vl = prefixVL + } + } + + if vl <= 0 { + // Cannot create an address without a valid lifetime. + return false + } + + // 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 the + // maximum temporary address preferred lifetime - the temporary address desync + // factor. + pl := ndp.configs.MaxTempAddrPreferredLifetime - ndp.temporaryAddressDesyncFactor + if prefixState.preferredUntil != (time.Time{}) { + if prefixPL := prefixState.preferredUntil.Sub(now); pl > prefixPL { + // Respect the preferred lifetime of the prefix, as per RFC 4941 section + // 3.3 step 4. + pl = prefixPL + } + } + + // As per RFC 4941 section 3.3 step 5, a temporary address is created only if + // the calculated preferred lifetime is greater than the advance regeneration + // duration. In particular, we MUST NOT create a temporary address with a zero + // Preferred Lifetime. + if pl <= ndp.configs.RegenAdvanceDuration { + return false + } + + generatedAddr := header.GenerateTempIPv6SLAACAddr(ndp.temporaryIIDHistory[:], stableAddr) + + // As per RFC RFC 4941 section 3.3 step 5, we MUST NOT create a temporary + // address with a zero preferred lifetime. The checks above ensure this + // so we know the address is not deprecated. + ref := ndp.addSLAACAddr(generatedAddr, slaacTemp, false /* deprecated */) + if ref == nil { + return false + } + + state := tempSLAACAddrState{ + deprecationTimer: tcpip.NewCancellableTimer(&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)) + } + + tempAddrState, ok := prefixState.tempAddrs[generatedAddr.Address] + if !ok { + panic(fmt.Sprintf("ndp: must have a tempAddr entry to deprecate temporary address %s", generatedAddr)) + } + + ndp.deprecateSLAACAddress(tempAddrState.ref) + }), + invalidationTimer: tcpip.NewCancellableTimer(&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)) + } + + tempAddrState, ok := prefixState.tempAddrs[generatedAddr.Address] + if !ok { + panic(fmt.Sprintf("ndp: must have a tempAddr entry to invalidate temporary address %s", generatedAddr)) + } + + ndp.invalidateTempSLAACAddr(prefixState.tempAddrs, generatedAddr.Address, tempAddrState) + }), + regenTimer: tcpip.NewCancellableTimer(&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)) + } + + tempAddrState, ok := prefixState.tempAddrs[generatedAddr.Address] + if !ok { + panic(fmt.Sprintf("ndp: must have a tempAddr entry to regenerate temporary address after %s", generatedAddr)) + } + + // If an address has already been regenerated for this address, don't + // regenerate another address. + if tempAddrState.regenerated { + return + } + + // Reset the generation attempts counter as we are starting the generation + // of a new address for the SLAAC prefix. + tempAddrState.regenerated = ndp.generateTempSLAACAddr(prefix, &prefixState, true /* resetGenAttempts */) + prefixState.tempAddrs[generatedAddr.Address] = tempAddrState + ndp.slaacPrefixes[prefix] = prefixState + }), + createdAt: now, + ref: ref, + } + + state.deprecationTimer.Reset(pl) + state.invalidationTimer.Reset(vl) + state.regenTimer.Reset(pl - ndp.configs.RegenAdvanceDuration) + + prefixState.generationAttempts++ + prefixState.tempAddrs[generatedAddr.Address] = state + + return true +} + +// regenerateTempSLAACAddr regenerates a temporary address for a SLAAC prefix. // // The NIC that ndp belongs to MUST be locked. -func (ndp *ndpState) refreshSLAACPrefixLifetimes(prefix tcpip.Subnet, pl, vl time.Duration) { - prefixState, ok := ndp.slaacPrefixes[prefix] +func (ndp *ndpState) regenerateTempSLAACAddr(prefix tcpip.Subnet, resetGenAttempts bool) { + state, ok := ndp.slaacPrefixes[prefix] if !ok { - panic(fmt.Sprintf("ndp: SLAAC prefix state not found to refresh lifetimes for %s", prefix)) + panic(fmt.Sprintf("ndp: SLAAC prefix state not found to regenerate temporary address for %s", prefix)) } - defer func() { ndp.slaacPrefixes[prefix] = prefixState }() + ndp.generateTempSLAACAddr(prefix, &state, resetGenAttempts) + ndp.slaacPrefixes[prefix] = state +} + +// refreshSLAACPrefixLifetimes refreshes the lifetimes of a SLAAC prefix. +// +// pl is the new preferred lifetime. vl is the new valid lifetime. +// +// The NIC that ndp belongs to MUST be locked. +func (ndp *ndpState) refreshSLAACPrefixLifetimes(prefix tcpip.Subnet, prefixState *slaacPrefixState, pl, vl time.Duration) { // If the preferred lifetime is zero, then the prefix should be deprecated. deprecated := pl == 0 if deprecated { - ndp.deprecateSLAACAddress(prefixState.ref) + ndp.deprecateSLAACAddress(prefixState.stableAddrRef) } else { - prefixState.ref.deprecated = false + prefixState.stableAddrRef.deprecated = false } // If prefix was preferred for some finite lifetime before, stop the @@ -1190,36 +1482,118 @@ func (ndp *ndpState) refreshSLAACPrefixLifetimes(prefix tcpip.Subnet, pl, vl tim // // 3) Otherwise, reset the valid lifetime of the prefix to 2 hours. - // Handle the infinite valid lifetime separately as we do not keep a timer in - // this case. if vl >= header.NDPInfiniteLifetime { + // Handle the infinite valid lifetime separately as we do not keep a timer + // in this case. prefixState.invalidationTimer.StopLocked() prefixState.validUntil = time.Time{} - return - } + } else { + var effectiveVl time.Duration + var rl time.Duration + + // If the prefix was originally set to be valid forever, assume the + // remaining time to be the maximum possible value. + if prefixState.validUntil == (time.Time{}) { + rl = header.NDPInfiniteLifetime + } else { + rl = time.Until(prefixState.validUntil) + } - var effectiveVl time.Duration - var rl time.Duration + if vl > MinPrefixInformationValidLifetimeForUpdate || vl > rl { + effectiveVl = vl + } else if rl > MinPrefixInformationValidLifetimeForUpdate { + effectiveVl = MinPrefixInformationValidLifetimeForUpdate + } - // If the prefix was originally set to be valid forever, assume the remaining - // time to be the maximum possible value. - if prefixState.validUntil == (time.Time{}) { - rl = header.NDPInfiniteLifetime - } else { - rl = time.Until(prefixState.validUntil) + if effectiveVl != 0 { + prefixState.invalidationTimer.StopLocked() + prefixState.invalidationTimer.Reset(effectiveVl) + prefixState.validUntil = now.Add(effectiveVl) + } } - if vl > MinPrefixInformationValidLifetimeForUpdate || vl > rl { - effectiveVl = vl - } else if rl <= MinPrefixInformationValidLifetimeForUpdate { + // If DAD is not yet complete on the stable address, there is no need to do + // work with temporary addresses. + if prefixState.stableAddrRef.getKind() != permanent { return - } else { - effectiveVl = MinPrefixInformationValidLifetimeForUpdate } - prefixState.invalidationTimer.StopLocked() - prefixState.invalidationTimer.Reset(effectiveVl) - prefixState.validUntil = now.Add(effectiveVl) + // 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. + var regenForAddr tcpip.Address + allAddressesRegenerated := true + for tempAddr, tempAddrState := range prefixState.tempAddrs { + // As per RFC 4941 section 3.3 step 4, the valid lifetime of a temporary + // address is the lower of the valid lifetime of the stable address or the + // maximum temporary address valid lifetime. Note, the valid lifetime of a + // temporary address is relative to the address's creation time. + validUntil := tempAddrState.createdAt.Add(ndp.configs.MaxTempAddrValidLifetime) + if prefixState.validUntil != (time.Time{}) && validUntil.Sub(prefixState.validUntil) > 0 { + validUntil = prefixState.validUntil + } + + // If the address is no longer valid, invalidate it immediately. Otherwise, + // reset the invalidation timer. + newValidLifetime := validUntil.Sub(now) + if newValidLifetime <= 0 { + ndp.invalidateTempSLAACAddr(prefixState.tempAddrs, tempAddr, tempAddrState) + continue + } + tempAddrState.invalidationTimer.StopLocked() + tempAddrState.invalidationTimer.Reset(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 + // the maximum temporary address preferred lifetime - the temporary address + // desync factor. Note, the preferred lifetime of a temporary address is + // relative to the address's creation time. + preferredUntil := tempAddrState.createdAt.Add(ndp.configs.MaxTempAddrPreferredLifetime - ndp.temporaryAddressDesyncFactor) + if prefixState.preferredUntil != (time.Time{}) && preferredUntil.Sub(prefixState.preferredUntil) > 0 { + preferredUntil = prefixState.preferredUntil + } + + // If the address is no longer preferred, deprecate it immediately. + // Otherwise, reset the deprecation timer. + newPreferredLifetime := preferredUntil.Sub(now) + tempAddrState.deprecationTimer.StopLocked() + if newPreferredLifetime <= 0 { + ndp.deprecateSLAACAddress(tempAddrState.ref) + } else { + tempAddrState.ref.deprecated = false + tempAddrState.deprecationTimer.Reset(newPreferredLifetime) + } + + tempAddrState.regenTimer.StopLocked() + if tempAddrState.regenerated { + } else { + allAddressesRegenerated = false + + if newPreferredLifetime <= ndp.configs.RegenAdvanceDuration { + // The new preferred lifetime is less than the advance regeneration + // duration so regenerate an address for this temporary address + // immediately after we finish iterating over the temporary addresses. + regenForAddr = tempAddr + } else { + tempAddrState.regenTimer.Reset(newPreferredLifetime - ndp.configs.RegenAdvanceDuration) + } + } + } + + // Generate a new temporary address if all of the existing temporary addresses + // have been regenerated, or we need to immediately regenerate an address + // due to an update in preferred lifetime. + // + // If each temporay address has already been regenerated, no new temporary + // address will be generated. To ensure continuation of temporary SLAAC + // addresses, we manually try to regenerate an address here. + if len(regenForAddr) != 0 || allAddressesRegenerated { + // Reset the generation attempts counter as we are starting the generation + // of a new address for the SLAAC prefix. + if state, ok := prefixState.tempAddrs[regenForAddr]; ndp.generateTempSLAACAddr(prefix, prefixState, true /* resetGenAttempts */) && ok { + state.regenerated = true + prefixState.tempAddrs[regenForAddr] = state + } + } } // deprecateSLAACAddress marks ref as deprecated and notifies the stack's NDP @@ -1243,11 +1617,11 @@ func (ndp *ndpState) deprecateSLAACAddress(ref *referencedNetworkEndpoint) { // // The NIC that ndp belongs to MUST be locked. func (ndp *ndpState) invalidateSLAACPrefix(prefix tcpip.Subnet, state slaacPrefixState) { - if r := state.ref; r != nil { + if r := state.stableAddrRef; r != nil { // Since we are already invalidating the prefix, do not invalidate the // prefix when removing the address. - if err := ndp.nic.removePermanentIPv6EndpointLocked(r, false /* allowSLAACPrefixInvalidation */); err != nil { - panic(fmt.Sprintf("ndp: removePermanentIPv6EndpointLocked(%s, false): %s", r.addrWithPrefix(), err)) + if err := ndp.nic.removePermanentIPv6EndpointLocked(r, false /* allowSLAACInvalidation */); err != nil { + panic(fmt.Sprintf("ndp: error removing stable SLAAC address %s: %s", r.addrWithPrefix(), err)) } } @@ -1265,14 +1639,14 @@ func (ndp *ndpState) cleanupSLAACAddrResourcesAndNotify(addr tcpip.AddressWithPr prefix := addr.Subnet() state, ok := ndp.slaacPrefixes[prefix] - if !ok || state.ref == nil || addr.Address != state.ref.ep.ID().LocalAddress { + if !ok || state.stableAddrRef == nil || addr.Address != state.stableAddrRef.ep.ID().LocalAddress { return } if !invalidatePrefix { // If the prefix is not being invalidated, disassociate the address from the // prefix and do nothing further. - state.ref = nil + state.stableAddrRef = nil ndp.slaacPrefixes[prefix] = state return } @@ -1286,11 +1660,68 @@ func (ndp *ndpState) cleanupSLAACAddrResourcesAndNotify(addr tcpip.AddressWithPr // // The NIC that ndp belongs to MUST be locked. func (ndp *ndpState) cleanupSLAACPrefixResources(prefix tcpip.Subnet, state slaacPrefixState) { + // Invalidate all temporary addresses. + for tempAddr, tempAddrState := range state.tempAddrs { + ndp.invalidateTempSLAACAddr(state.tempAddrs, tempAddr, tempAddrState) + } + + state.stableAddrRef = nil state.deprecationTimer.StopLocked() state.invalidationTimer.StopLocked() delete(ndp.slaacPrefixes, prefix) } +// invalidateTempSLAACAddr invalidates a temporary SLAAC address. +// +// The NIC that ndp belongs to MUST be locked. +func (ndp *ndpState) invalidateTempSLAACAddr(tempAddrs map[tcpip.Address]tempSLAACAddrState, tempAddr tcpip.Address, tempAddrState tempSLAACAddrState) { + // Since we are already invalidating the address, do not invalidate the + // address when removing the address. + if err := ndp.nic.removePermanentIPv6EndpointLocked(tempAddrState.ref, false /* allowSLAACInvalidation */); err != nil { + panic(fmt.Sprintf("error removing temporary SLAAC address %s: %s", tempAddrState.ref.addrWithPrefix(), err)) + } + + ndp.cleanupTempSLAACAddrResources(tempAddrs, tempAddr, tempAddrState) +} + +// cleanupTempSLAACAddrResourcesAndNotify cleans up an invalidated temporary +// SLAAC address's resources from ndp. +// +// The NIC that ndp belongs to MUST be locked. +func (ndp *ndpState) cleanupTempSLAACAddrResourcesAndNotify(addr tcpip.AddressWithPrefix, invalidateAddr bool) { + if ndpDisp := ndp.nic.stack.ndpDisp; ndpDisp != nil { + ndpDisp.OnAutoGenAddressInvalidated(ndp.nic.ID(), addr) + } + + if !invalidateAddr { + return + } + + prefix := addr.Subnet() + state, ok := ndp.slaacPrefixes[prefix] + if !ok { + panic(fmt.Sprintf("ndp: must have a slaacPrefixes entry to clean up temp addr %s resources", addr)) + } + + tempAddrState, ok := state.tempAddrs[addr.Address] + if !ok { + panic(fmt.Sprintf("ndp: must have a tempAddr entry to clean up temp addr %s resources", addr)) + } + + ndp.cleanupTempSLAACAddrResources(state.tempAddrs, addr.Address, tempAddrState) +} + +// cleanupTempSLAACAddrResourcesAndNotify cleans up a temporary SLAAC address's +// timers 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() + delete(tempAddrs, tempAddr) +} + // cleanupState cleans up ndp's state. // // If hostOnly is true, then only host-specific state will be cleaned up. @@ -1450,3 +1881,13 @@ func (ndp *ndpState) stopSolicitingRouters() { ndp.rtrSolicitTimer.Stop() ndp.rtrSolicitTimer = nil } + +// initializeTempAddrState initializes state related to temporary SLAAC +// addresses. +func (ndp *ndpState) initializeTempAddrState() { + header.InitialTempIID(ndp.temporaryIIDHistory[:], ndp.nic.stack.tempIIDSeed, ndp.nic.ID()) + + if MaxDesyncFactor != 0 { + ndp.temporaryAddressDesyncFactor = time.Duration(rand.Int63n(int64(MaxDesyncFactor))) + } +} diff --git a/pkg/tcpip/stack/ndp_test.go b/pkg/tcpip/stack/ndp_test.go index 6dd460984..421df674f 100644 --- a/pkg/tcpip/stack/ndp_test.go +++ b/pkg/tcpip/stack/ndp_test.go @@ -1801,6 +1801,726 @@ func TestAutoGenAddr(t *testing.T) { } } +func addressCheck(addrs []tcpip.ProtocolAddress, containList, notContainList []tcpip.AddressWithPrefix) string { + ret := "" + for _, c := range containList { + if !containsV6Addr(addrs, c) { + ret += fmt.Sprintf("should have %s in the list of addresses\n", c) + } + } + for _, c := range notContainList { + if containsV6Addr(addrs, c) { + ret += fmt.Sprintf("should not have %s in the list of addresses\n", c) + } + } + return ret +} + +// TestAutoGenTempAddr tests that temporary SLAAC addresses are generated when +// configured to do so as part of IPv6 Privacy Extensions. +func TestAutoGenTempAddr(t *testing.T) { + const ( + nicID = 1 + newMinVL = 5 + newMinVLDuration = newMinVL * time.Second + ) + + savedMinPrefixInformationValidLifetimeForUpdate := stack.MinPrefixInformationValidLifetimeForUpdate + savedMaxDesync := stack.MaxDesyncFactor + defer func() { + stack.MinPrefixInformationValidLifetimeForUpdate = savedMinPrefixInformationValidLifetimeForUpdate + stack.MaxDesyncFactor = savedMaxDesync + }() + stack.MinPrefixInformationValidLifetimeForUpdate = newMinVLDuration + stack.MaxDesyncFactor = time.Nanosecond + + prefix1, _, addr1 := prefixSubnetAddr(0, linkAddr1) + prefix2, _, addr2 := prefixSubnetAddr(1, linkAddr1) + + tests := []struct { + name string + dupAddrTransmits uint8 + retransmitTimer time.Duration + }{ + { + name: "DAD disabled", + }, + { + name: "DAD enabled", + dupAddrTransmits: 1, + retransmitTimer: time.Second, + }, + } + + // This Run will not return until the parallel tests finish. + // + // We need this because we need to do some teardown work after the + // parallel tests complete. + // + // See https://godoc.org/testing#hdr-Subtests_and_Sub_benchmarks for + // more details. + t.Run("group", func(t *testing.T) { + for i, test := range tests { + i := i + test := test + + t.Run(test.name, func(t *testing.T) { + t.Parallel() + + seed := []byte{uint8(i)} + var tempIIDHistory [header.IIDSize]byte + header.InitialTempIID(tempIIDHistory[:], seed, nicID) + newTempAddr := func(stableAddr tcpip.Address) tcpip.AddressWithPrefix { + return header.GenerateTempIPv6SLAACAddr(tempIIDHistory[:], stableAddr) + } + + ndpDisp := ndpDispatcher{ + dadC: make(chan ndpDADEvent, 2), + autoGenAddrC: make(chan ndpAutoGenAddrEvent, 2), + } + e := channel.New(0, 1280, linkAddr1) + s := stack.New(stack.Options{ + NetworkProtocols: []stack.NetworkProtocol{ipv6.NewProtocol()}, + NDPConfigs: stack.NDPConfigurations{ + DupAddrDetectTransmits: test.dupAddrTransmits, + RetransmitTimer: test.retransmitTimer, + HandleRAs: true, + AutoGenGlobalAddresses: true, + AutoGenTempGlobalAddresses: true, + }, + NDPDisp: &ndpDisp, + TempIIDSeed: seed, + }) + + if err := s.CreateNIC(nicID, e); err != nil { + t.Fatalf("CreateNIC(%d, _) = %s", nicID, err) + } + + expectAutoGenAddrEvent := func(addr tcpip.AddressWithPrefix, eventType ndpAutoGenAddrEventType) { + t.Helper() + + select { + case e := <-ndpDisp.autoGenAddrC: + if diff := checkAutoGenAddrEvent(e, addr, eventType); diff != "" { + t.Errorf("auto-gen addr event mismatch (-want +got):\n%s", diff) + } + default: + t.Fatal("expected addr auto gen event") + } + } + + expectAutoGenAddrEventAsync := func(addr tcpip.AddressWithPrefix, eventType ndpAutoGenAddrEventType) { + t.Helper() + + select { + case e := <-ndpDisp.autoGenAddrC: + if diff := checkAutoGenAddrEvent(e, addr, eventType); diff != "" { + t.Errorf("auto-gen addr event mismatch (-want +got):\n%s", diff) + } + case <-time.After(defaultAsyncEventTimeout): + t.Fatal("timed out waiting for addr auto gen event") + } + } + + expectDADEventAsync := func(addr tcpip.Address) { + t.Helper() + + select { + case e := <-ndpDisp.dadC: + if diff := checkDADEvent(e, nicID, addr, true, nil); diff != "" { + t.Errorf("dad event mismatch (-want +got):\n%s", diff) + } + case <-time.After(time.Duration(test.dupAddrTransmits)*test.retransmitTimer + defaultAsyncEventTimeout): + t.Fatal("timed out waiting for DAD event") + } + } + + // Receive an RA with prefix1 in an NDP Prefix Information option (PI) + // with zero valid lifetime. + e.InjectInbound(header.IPv6ProtocolNumber, raBufWithPI(llAddr2, 0, prefix1, true, true, 0, 0)) + select { + case e := <-ndpDisp.autoGenAddrC: + t.Fatalf("unexpectedly auto-generated an address with 0 lifetime; event = %+v", e) + default: + } + + // Receive an RA with prefix1 in an NDP Prefix Information option (PI) + // with non-zero valid lifetime. + e.InjectInbound(header.IPv6ProtocolNumber, raBufWithPI(llAddr2, 0, prefix1, true, true, 100, 0)) + expectAutoGenAddrEvent(addr1, newAddr) + expectDADEventAsync(addr1.Address) + select { + case e := <-ndpDisp.autoGenAddrC: + t.Fatalf("unexpectedly got an auto gen addr event = %+v", e) + default: + } + if mismatch := addressCheck(s.NICInfo()[nicID].ProtocolAddresses, []tcpip.AddressWithPrefix{addr1}, nil); mismatch != "" { + t.Fatal(mismatch) + } + + // Receive an RA with prefix1 in an NDP Prefix Information option (PI) + // with non-zero valid & preferred lifetimes. + tempAddr1 := newTempAddr(addr1.Address) + e.InjectInbound(header.IPv6ProtocolNumber, raBufWithPI(llAddr2, 0, prefix1, true, true, 100, 100)) + expectAutoGenAddrEvent(tempAddr1, newAddr) + expectDADEventAsync(tempAddr1.Address) + if mismatch := addressCheck(s.NICInfo()[1].ProtocolAddresses, []tcpip.AddressWithPrefix{addr1, tempAddr1}, nil); mismatch != "" { + t.Fatal(mismatch) + } + + // Receive an RA with prefix2 in an NDP Prefix Information option (PI) + // with preferred lifetime > valid lifetime + e.InjectInbound(header.IPv6ProtocolNumber, raBufWithPI(llAddr2, 0, prefix1, true, true, 5, 6)) + select { + case e := <-ndpDisp.autoGenAddrC: + t.Fatalf("unexpectedly auto-generated an address with preferred lifetime > valid lifetime; event = %+v", e) + default: + } + if mismatch := addressCheck(s.NICInfo()[nicID].ProtocolAddresses, []tcpip.AddressWithPrefix{addr1, tempAddr1}, nil); mismatch != "" { + t.Fatal(mismatch) + } + + // Receive an RA with prefix2 in a PI w/ non-zero valid and preferred + // lifetimes. + tempAddr2 := newTempAddr(addr2.Address) + e.InjectInbound(header.IPv6ProtocolNumber, raBufWithPI(llAddr2, 0, prefix2, true, true, 100, 100)) + expectAutoGenAddrEvent(addr2, newAddr) + expectDADEventAsync(addr2.Address) + expectAutoGenAddrEventAsync(tempAddr2, newAddr) + expectDADEventAsync(tempAddr2.Address) + if mismatch := addressCheck(s.NICInfo()[nicID].ProtocolAddresses, []tcpip.AddressWithPrefix{addr1, tempAddr1, addr2, tempAddr2}, nil); mismatch != "" { + t.Fatal(mismatch) + } + + // Deprecate prefix1. + e.InjectInbound(header.IPv6ProtocolNumber, raBufWithPI(llAddr2, 0, prefix1, true, true, 100, 0)) + expectAutoGenAddrEvent(addr1, deprecatedAddr) + expectAutoGenAddrEvent(tempAddr1, deprecatedAddr) + if mismatch := addressCheck(s.NICInfo()[nicID].ProtocolAddresses, []tcpip.AddressWithPrefix{addr1, tempAddr1, addr2, tempAddr2}, nil); mismatch != "" { + t.Fatal(mismatch) + } + + // Refresh lifetimes for prefix1. + e.InjectInbound(header.IPv6ProtocolNumber, raBufWithPI(llAddr2, 0, prefix1, true, true, 100, 100)) + if mismatch := addressCheck(s.NICInfo()[nicID].ProtocolAddresses, []tcpip.AddressWithPrefix{addr1, tempAddr1, addr2, tempAddr2}, nil); mismatch != "" { + t.Fatal(mismatch) + } + + // Reduce valid lifetime and deprecate addresses of prefix1. + e.InjectInbound(header.IPv6ProtocolNumber, raBufWithPI(llAddr2, 0, prefix1, true, true, newMinVL, 0)) + expectAutoGenAddrEvent(addr1, deprecatedAddr) + expectAutoGenAddrEvent(tempAddr1, deprecatedAddr) + if mismatch := addressCheck(s.NICInfo()[nicID].ProtocolAddresses, []tcpip.AddressWithPrefix{addr1, tempAddr1, addr2, tempAddr2}, nil); mismatch != "" { + t.Fatal(mismatch) + } + + // Wait for addrs of prefix1 to be invalidated. They should be + // invalidated at the same time. + select { + case e := <-ndpDisp.autoGenAddrC: + var nextAddr tcpip.AddressWithPrefix + if e.addr == addr1 { + if diff := checkAutoGenAddrEvent(e, addr1, invalidatedAddr); diff != "" { + t.Errorf("auto-gen addr event mismatch (-want +got):\n%s", diff) + } + nextAddr = tempAddr1 + } else { + if diff := checkAutoGenAddrEvent(e, tempAddr1, invalidatedAddr); diff != "" { + t.Errorf("auto-gen addr event mismatch (-want +got):\n%s", diff) + } + nextAddr = addr1 + } + + select { + case e := <-ndpDisp.autoGenAddrC: + if diff := checkAutoGenAddrEvent(e, nextAddr, invalidatedAddr); diff != "" { + t.Errorf("auto-gen addr event mismatch (-want +got):\n%s", diff) + } + case <-time.After(defaultTimeout): + t.Fatal("timed out waiting for addr auto gen event") + } + case <-time.After(newMinVLDuration + defaultTimeout): + t.Fatal("timed out waiting for addr auto gen event") + } + if mismatch := addressCheck(s.NICInfo()[nicID].ProtocolAddresses, []tcpip.AddressWithPrefix{addr2, tempAddr2}, []tcpip.AddressWithPrefix{addr1, tempAddr1}); mismatch != "" { + t.Fatal(mismatch) + } + + // Receive an RA with prefix2 in a PI w/ 0 lifetimes. + e.InjectInbound(header.IPv6ProtocolNumber, raBufWithPI(llAddr2, 0, prefix2, true, true, 0, 0)) + expectAutoGenAddrEvent(addr2, deprecatedAddr) + expectAutoGenAddrEvent(tempAddr2, deprecatedAddr) + select { + case e := <-ndpDisp.autoGenAddrC: + t.Errorf("got unexpected auto gen addr event = %+v", e) + default: + } + if mismatch := addressCheck(s.NICInfo()[nicID].ProtocolAddresses, []tcpip.AddressWithPrefix{addr2, tempAddr2}, []tcpip.AddressWithPrefix{addr1, tempAddr1}); mismatch != "" { + t.Fatal(mismatch) + } + }) + } + }) +} + +// TestNoAutoGenTempAddrForLinkLocal test that temporary SLAAC addresses are not +// generated for auto generated link-local addresses. +func TestNoAutoGenTempAddrForLinkLocal(t *testing.T) { + const nicID = 1 + + savedMaxDesyncFactor := stack.MaxDesyncFactor + defer func() { + stack.MaxDesyncFactor = savedMaxDesyncFactor + }() + stack.MaxDesyncFactor = time.Nanosecond + + tests := []struct { + name string + dupAddrTransmits uint8 + retransmitTimer time.Duration + }{ + { + name: "DAD disabled", + }, + { + name: "DAD enabled", + dupAddrTransmits: 1, + retransmitTimer: time.Second, + }, + } + + // This Run will not return until the parallel tests finish. + // + // We need this because we need to do some teardown work after the + // parallel tests complete. + // + // See https://godoc.org/testing#hdr-Subtests_and_Sub_benchmarks for + // more details. + t.Run("group", func(t *testing.T) { + for _, test := range tests { + test := test + + t.Run(test.name, func(t *testing.T) { + t.Parallel() + + ndpDisp := ndpDispatcher{ + dadC: make(chan ndpDADEvent, 1), + autoGenAddrC: make(chan ndpAutoGenAddrEvent, 1), + } + e := channel.New(0, 1280, linkAddr1) + s := stack.New(stack.Options{ + NetworkProtocols: []stack.NetworkProtocol{ipv6.NewProtocol()}, + NDPConfigs: stack.NDPConfigurations{ + AutoGenTempGlobalAddresses: true, + }, + NDPDisp: &ndpDisp, + AutoGenIPv6LinkLocal: true, + }) + + if err := s.CreateNIC(nicID, e); err != nil { + t.Fatalf("CreateNIC(%d, _) = %s", nicID, err) + } + + // The stable link-local address should auto-generate and resolve DAD. + select { + case e := <-ndpDisp.autoGenAddrC: + if diff := checkAutoGenAddrEvent(e, tcpip.AddressWithPrefix{Address: llAddr1, PrefixLen: header.IIDOffsetInIPv6Address * 8}, newAddr); diff != "" { + t.Errorf("auto-gen addr event mismatch (-want +got):\n%s", diff) + } + default: + t.Fatal("expected addr auto gen event") + } + select { + case e := <-ndpDisp.dadC: + if diff := checkDADEvent(e, nicID, llAddr1, true, nil); diff != "" { + t.Errorf("dad event mismatch (-want +got):\n%s", diff) + } + case <-time.After(time.Duration(test.dupAddrTransmits)*test.retransmitTimer + defaultAsyncEventTimeout): + t.Fatal("timed out waiting for DAD event") + } + + // No new addresses should be generated. + select { + case e := <-ndpDisp.autoGenAddrC: + t.Errorf("got unxpected auto gen addr event = %+v", e) + case <-time.After(defaultAsyncEventTimeout): + } + }) + } + }) +} + +// TestNoAutoGenTempAddrWithoutStableAddr tests that a temporary SLAAC address +// will not be generated until after DAD completes, even if a new Router +// Advertisement is received to refresh lifetimes. +func TestNoAutoGenTempAddrWithoutStableAddr(t *testing.T) { + const ( + nicID = 1 + dadTransmits = 1 + retransmitTimer = 2 * time.Second + ) + + savedMaxDesyncFactor := stack.MaxDesyncFactor + defer func() { + stack.MaxDesyncFactor = savedMaxDesyncFactor + }() + stack.MaxDesyncFactor = 0 + + prefix, _, addr := prefixSubnetAddr(0, linkAddr1) + var tempIIDHistory [header.IIDSize]byte + header.InitialTempIID(tempIIDHistory[:], nil, nicID) + tempAddr := header.GenerateTempIPv6SLAACAddr(tempIIDHistory[:], addr.Address) + + ndpDisp := ndpDispatcher{ + dadC: make(chan ndpDADEvent, 1), + autoGenAddrC: make(chan ndpAutoGenAddrEvent, 1), + } + e := channel.New(0, 1280, linkAddr1) + s := stack.New(stack.Options{ + NetworkProtocols: []stack.NetworkProtocol{ipv6.NewProtocol()}, + NDPConfigs: stack.NDPConfigurations{ + DupAddrDetectTransmits: dadTransmits, + RetransmitTimer: retransmitTimer, + HandleRAs: true, + AutoGenGlobalAddresses: true, + AutoGenTempGlobalAddresses: true, + }, + NDPDisp: &ndpDisp, + }) + + if err := s.CreateNIC(nicID, e); err != nil { + t.Fatalf("CreateNIC(%d, _) = %s", nicID, err) + } + + // Receive an RA to trigger SLAAC for prefix. + e.InjectInbound(header.IPv6ProtocolNumber, raBufWithPI(llAddr2, 0, prefix, true, true, 100, 100)) + select { + case e := <-ndpDisp.autoGenAddrC: + if diff := checkAutoGenAddrEvent(e, addr, newAddr); diff != "" { + t.Errorf("auto-gen addr event mismatch (-want +got):\n%s", diff) + } + default: + t.Fatal("expected addr auto gen event") + } + + // DAD on the stable address for prefix has not yet completed. Receiving a new + // RA that would refresh lifetimes should not generate a temporary SLAAC + // address for the prefix. + e.InjectInbound(header.IPv6ProtocolNumber, raBufWithPI(llAddr2, 0, prefix, true, true, 100, 100)) + select { + case e := <-ndpDisp.autoGenAddrC: + t.Fatalf("unexpected auto gen addr event = %+v", e) + default: + } + + // Wait for DAD to complete for the stable address then expect the temporary + // address to be generated. + select { + case e := <-ndpDisp.dadC: + if diff := checkDADEvent(e, nicID, addr.Address, true, nil); diff != "" { + t.Errorf("dad event mismatch (-want +got):\n%s", diff) + } + case <-time.After(dadTransmits*retransmitTimer + defaultAsyncEventTimeout): + t.Fatal("timed out waiting for DAD event") + } + select { + case e := <-ndpDisp.autoGenAddrC: + if diff := checkAutoGenAddrEvent(e, tempAddr, newAddr); diff != "" { + t.Errorf("auto-gen addr event mismatch (-want +got):\n%s", diff) + } + case <-time.After(defaultAsyncEventTimeout): + t.Fatal("timed out waiting for addr auto gen event") + } +} + +// TestAutoGenTempAddrRegen tests that temporary SLAAC addresses are +// regenerated. +func TestAutoGenTempAddrRegen(t *testing.T) { + const ( + nicID = 1 + regenAfter = 2 * time.Second + newMinVL = 10 + newMinVLDuration = newMinVL * time.Second + ) + + savedMaxDesyncFactor := stack.MaxDesyncFactor + savedMinMaxTempAddrPreferredLifetime := stack.MinMaxTempAddrPreferredLifetime + savedMinMaxTempAddrValidLifetime := stack.MinMaxTempAddrValidLifetime + defer func() { + stack.MaxDesyncFactor = savedMaxDesyncFactor + stack.MinMaxTempAddrPreferredLifetime = savedMinMaxTempAddrPreferredLifetime + stack.MinMaxTempAddrValidLifetime = savedMinMaxTempAddrValidLifetime + }() + stack.MaxDesyncFactor = 0 + stack.MinMaxTempAddrPreferredLifetime = newMinVLDuration + stack.MinMaxTempAddrValidLifetime = newMinVLDuration + + prefix, _, addr := prefixSubnetAddr(0, linkAddr1) + var tempIIDHistory [header.IIDSize]byte + header.InitialTempIID(tempIIDHistory[:], nil, nicID) + tempAddr1 := header.GenerateTempIPv6SLAACAddr(tempIIDHistory[:], addr.Address) + tempAddr2 := header.GenerateTempIPv6SLAACAddr(tempIIDHistory[:], addr.Address) + tempAddr3 := header.GenerateTempIPv6SLAACAddr(tempIIDHistory[:], addr.Address) + + ndpDisp := ndpDispatcher{ + autoGenAddrC: make(chan ndpAutoGenAddrEvent, 2), + } + e := channel.New(0, 1280, linkAddr1) + ndpConfigs := stack.NDPConfigurations{ + HandleRAs: true, + AutoGenGlobalAddresses: true, + AutoGenTempGlobalAddresses: true, + RegenAdvanceDuration: newMinVLDuration - regenAfter, + } + s := stack.New(stack.Options{ + NetworkProtocols: []stack.NetworkProtocol{ipv6.NewProtocol()}, + NDPConfigs: ndpConfigs, + NDPDisp: &ndpDisp, + }) + + if err := s.CreateNIC(nicID, e); err != nil { + t.Fatalf("CreateNIC(%d, _) = %s", nicID, err) + } + + expectAutoGenAddrEvent := func(addr tcpip.AddressWithPrefix, eventType ndpAutoGenAddrEventType) { + t.Helper() + + select { + case e := <-ndpDisp.autoGenAddrC: + if diff := checkAutoGenAddrEvent(e, addr, eventType); diff != "" { + t.Errorf("auto-gen addr event mismatch (-want +got):\n%s", diff) + } + default: + t.Fatal("expected addr auto gen event") + } + } + + expectAutoGenAddrEventAsync := func(addr tcpip.AddressWithPrefix, eventType ndpAutoGenAddrEventType, timeout time.Duration) { + t.Helper() + + select { + case e := <-ndpDisp.autoGenAddrC: + if diff := checkAutoGenAddrEvent(e, addr, eventType); diff != "" { + t.Errorf("auto-gen addr event mismatch (-want +got):\n%s", diff) + } + case <-time.After(timeout): + t.Fatal("timed out waiting for addr auto gen event") + } + } + + // Receive an RA with prefix1 in an NDP Prefix Information option (PI) + // with non-zero valid & preferred lifetimes. + e.InjectInbound(header.IPv6ProtocolNumber, raBufWithPI(llAddr2, 0, prefix, true, true, 100, 100)) + expectAutoGenAddrEvent(addr, newAddr) + expectAutoGenAddrEvent(tempAddr1, newAddr) + if mismatch := addressCheck(s.NICInfo()[nicID].ProtocolAddresses, []tcpip.AddressWithPrefix{addr, tempAddr1}, nil); mismatch != "" { + t.Fatal(mismatch) + } + + // Wait for regeneration + expectAutoGenAddrEventAsync(tempAddr2, newAddr, regenAfter+defaultAsyncEventTimeout) + if mismatch := addressCheck(s.NICInfo()[nicID].ProtocolAddresses, []tcpip.AddressWithPrefix{addr, tempAddr1, tempAddr2}, nil); mismatch != "" { + t.Fatal(mismatch) + } + + // Wait for regeneration + expectAutoGenAddrEventAsync(tempAddr3, newAddr, regenAfter+defaultAsyncEventTimeout) + if mismatch := addressCheck(s.NICInfo()[nicID].ProtocolAddresses, []tcpip.AddressWithPrefix{addr, tempAddr1, tempAddr2, tempAddr3}, nil); mismatch != "" { + t.Fatal(mismatch) + } + + // Stop generating temporary addresses + ndpConfigs.AutoGenTempGlobalAddresses = false + if err := s.SetNDPConfigurations(nicID, ndpConfigs); err != nil { + t.Fatalf("s.SetNDPConfigurations(%d, _): %s", nicID, err) + } + + // Wait for all the temporary addresses to get invalidated. + tempAddrs := []tcpip.AddressWithPrefix{tempAddr1, tempAddr2, tempAddr3} + invalidateAfter := newMinVLDuration - 2*regenAfter + for _, addr := range tempAddrs { + // Wait for a deprecation then invalidation event, or just an invalidation + // event. We need to cover both cases but cannot deterministically hit both + // cases because the deprecation and invalidation timers could fire in any + // order. + select { + case e := <-ndpDisp.autoGenAddrC: + if diff := checkAutoGenAddrEvent(e, addr, deprecatedAddr); diff == "" { + // If we get a deprecation event first, we should get an invalidation + // event almost immediately after. + select { + case e := <-ndpDisp.autoGenAddrC: + if diff := checkAutoGenAddrEvent(e, addr, invalidatedAddr); diff != "" { + t.Errorf("auto-gen addr event mismatch (-want +got):\n%s", diff) + } + case <-time.After(defaultAsyncEventTimeout): + t.Fatal("timed out waiting for addr auto gen event") + } + } else if diff := checkAutoGenAddrEvent(e, addr, invalidatedAddr); diff == "" { + // If we get an invalidation event first, we shouldn't get a deprecation + // event after. + select { + case e := <-ndpDisp.autoGenAddrC: + t.Fatalf("unexpectedly got an auto-generated event = %+v", e) + case <-time.After(defaultTimeout): + } + } else { + t.Fatalf("got unexpected auto-generated event = %+v", e) + } + case <-time.After(invalidateAfter + defaultAsyncEventTimeout): + t.Fatal("timed out waiting for addr auto gen event") + } + + invalidateAfter = regenAfter + } + if mismatch := addressCheck(s.NICInfo()[1].ProtocolAddresses, []tcpip.AddressWithPrefix{addr}, tempAddrs); mismatch != "" { + t.Fatal(mismatch) + } +} + +// TestAutoGenTempAddrRegenTimerUpdates tests that a temporary address's +// regeneration timer gets updated when refreshing the address's lifetimes. +func TestAutoGenTempAddrRegenTimerUpdates(t *testing.T) { + const ( + nicID = 1 + regenAfter = 2 * time.Second + newMinVL = 10 + newMinVLDuration = newMinVL * time.Second + ) + + savedMaxDesyncFactor := stack.MaxDesyncFactor + savedMinMaxTempAddrPreferredLifetime := stack.MinMaxTempAddrPreferredLifetime + savedMinMaxTempAddrValidLifetime := stack.MinMaxTempAddrValidLifetime + defer func() { + stack.MaxDesyncFactor = savedMaxDesyncFactor + stack.MinMaxTempAddrPreferredLifetime = savedMinMaxTempAddrPreferredLifetime + stack.MinMaxTempAddrValidLifetime = savedMinMaxTempAddrValidLifetime + }() + stack.MaxDesyncFactor = 0 + stack.MinMaxTempAddrPreferredLifetime = newMinVLDuration + stack.MinMaxTempAddrValidLifetime = newMinVLDuration + + prefix, _, addr := prefixSubnetAddr(0, linkAddr1) + var tempIIDHistory [header.IIDSize]byte + header.InitialTempIID(tempIIDHistory[:], nil, nicID) + tempAddr1 := header.GenerateTempIPv6SLAACAddr(tempIIDHistory[:], addr.Address) + tempAddr2 := header.GenerateTempIPv6SLAACAddr(tempIIDHistory[:], addr.Address) + tempAddr3 := header.GenerateTempIPv6SLAACAddr(tempIIDHistory[:], addr.Address) + + ndpDisp := ndpDispatcher{ + autoGenAddrC: make(chan ndpAutoGenAddrEvent, 2), + } + e := channel.New(0, 1280, linkAddr1) + ndpConfigs := stack.NDPConfigurations{ + HandleRAs: true, + AutoGenGlobalAddresses: true, + AutoGenTempGlobalAddresses: true, + RegenAdvanceDuration: newMinVLDuration - regenAfter, + } + s := stack.New(stack.Options{ + NetworkProtocols: []stack.NetworkProtocol{ipv6.NewProtocol()}, + NDPConfigs: ndpConfigs, + NDPDisp: &ndpDisp, + }) + + if err := s.CreateNIC(nicID, e); err != nil { + t.Fatalf("CreateNIC(%d, _) = %s", nicID, err) + } + + expectAutoGenAddrEvent := func(addr tcpip.AddressWithPrefix, eventType ndpAutoGenAddrEventType) { + t.Helper() + + select { + case e := <-ndpDisp.autoGenAddrC: + if diff := checkAutoGenAddrEvent(e, addr, eventType); diff != "" { + t.Errorf("auto-gen addr event mismatch (-want +got):\n%s", diff) + } + default: + t.Fatal("expected addr auto gen event") + } + } + + expectAutoGenAddrEventAsync := func(addr tcpip.AddressWithPrefix, eventType ndpAutoGenAddrEventType, timeout time.Duration) { + t.Helper() + + select { + case e := <-ndpDisp.autoGenAddrC: + if diff := checkAutoGenAddrEvent(e, addr, eventType); diff != "" { + t.Errorf("auto-gen addr event mismatch (-want +got):\n%s", diff) + } + case <-time.After(timeout): + t.Fatal("timed out waiting for addr auto gen event") + } + } + + // Receive an RA with prefix1 in an NDP Prefix Information option (PI) + // with non-zero valid & preferred lifetimes. + e.InjectInbound(header.IPv6ProtocolNumber, raBufWithPI(llAddr2, 0, prefix, true, true, 100, 100)) + expectAutoGenAddrEvent(addr, newAddr) + expectAutoGenAddrEvent(tempAddr1, newAddr) + if mismatch := addressCheck(s.NICInfo()[nicID].ProtocolAddresses, []tcpip.AddressWithPrefix{addr, tempAddr1}, nil); mismatch != "" { + t.Fatal(mismatch) + } + + // Deprecate the prefix. + // + // A new temporary address should be generated after the regeneration + // time has passed since the prefix is deprecated. + e.InjectInbound(header.IPv6ProtocolNumber, raBufWithPI(llAddr2, 0, prefix, true, true, 100, 0)) + expectAutoGenAddrEvent(addr, deprecatedAddr) + expectAutoGenAddrEvent(tempAddr1, deprecatedAddr) + select { + case e := <-ndpDisp.autoGenAddrC: + t.Fatalf("unexpected auto gen addr event = %+v", e) + case <-time.After(regenAfter + defaultAsyncEventTimeout): + } + + // Prefer the prefix again. + // + // A new temporary address should immediately be generated since the + // regeneration time has already passed since the last address was generated + // - this regeneration does not depend on a timer. + e.InjectInbound(header.IPv6ProtocolNumber, raBufWithPI(llAddr2, 0, prefix, true, true, 100, 100)) + expectAutoGenAddrEvent(tempAddr2, newAddr) + + // Increase the maximum lifetimes for temporary addresses to large values + // then refresh the lifetimes of the prefix. + // + // A new address should not be generated after the regeneration time that was + // expected for the previous check. This is because the preferred lifetime for + // the temporary addresses has increased, so it will take more time to + // regenerate a new temporary address. Note, new addresses are only + // regenerated after the preferred lifetime - the regenerate advance duration + // as paased. + ndpConfigs.MaxTempAddrValidLifetime = 100 * time.Second + ndpConfigs.MaxTempAddrPreferredLifetime = 100 * time.Second + if err := s.SetNDPConfigurations(nicID, ndpConfigs); err != nil { + t.Fatalf("s.SetNDPConfigurations(%d, _): %s", nicID, err) + } + e.InjectInbound(header.IPv6ProtocolNumber, raBufWithPI(llAddr2, 0, prefix, true, true, 100, 100)) + select { + case e := <-ndpDisp.autoGenAddrC: + t.Fatalf("unexpected auto gen addr event = %+v", e) + case <-time.After(regenAfter + defaultAsyncEventTimeout): + } + + // Set the maximum lifetimes for temporary addresses such that on the next + // RA, the regeneration timer gets reset. + // + // The maximum lifetime is the sum of the minimum lifetimes for temporary + // addresses + the time that has already passed since the last address was + // generated so that the regeneration timer is needed to generate the next + // address. + newLifetimes := newMinVLDuration + regenAfter + defaultAsyncEventTimeout + ndpConfigs.MaxTempAddrValidLifetime = newLifetimes + ndpConfigs.MaxTempAddrPreferredLifetime = newLifetimes + if err := s.SetNDPConfigurations(nicID, ndpConfigs); err != nil { + t.Fatalf("s.SetNDPConfigurations(%d, _): %s", nicID, err) + } + e.InjectInbound(header.IPv6ProtocolNumber, raBufWithPI(llAddr2, 0, prefix, true, true, 100, 100)) + expectAutoGenAddrEventAsync(tempAddr3, newAddr, regenAfter+defaultAsyncEventTimeout) +} + // stackAndNdpDispatcherWithDefaultRoute returns an ndpDispatcher, // channel.Endpoint and stack.Stack. // @@ -2196,7 +2916,6 @@ func TestAutoGenAddrTimerDeprecation(t *testing.T) { } else { t.Fatalf("got unexpected auto-generated event") } - case <-time.After(newMinVLDuration + defaultAsyncEventTimeout): t.Fatal("timed out waiting for addr auto gen event") } @@ -2808,9 +3527,7 @@ func TestAutoGenAddrWithOpaqueIID(t *testing.T) { } } -// TestAutoGenAddrWithOpaqueIIDDADRetries tests the regeneration of an -// auto-generated IPv6 address in response to a DAD conflict. -func TestAutoGenAddrWithOpaqueIIDDADRetries(t *testing.T) { +func TestAutoGenAddrInResponseToDADConflicts(t *testing.T) { const nicID = 1 const nicName = "nic" const dadTransmits = 1 @@ -2818,6 +3535,13 @@ func TestAutoGenAddrWithOpaqueIIDDADRetries(t *testing.T) { const maxMaxRetries = 3 const lifetimeSeconds = 10 + // Needed for the temporary address sub test. + savedMaxDesync := stack.MaxDesyncFactor + defer func() { + stack.MaxDesyncFactor = savedMaxDesync + }() + stack.MaxDesyncFactor = time.Nanosecond + var secretKeyBuf [header.OpaqueIIDSecretKeyMinBytes]byte secretKey := secretKeyBuf[:] n, err := rand.Read(secretKey) @@ -2830,185 +3554,234 @@ func TestAutoGenAddrWithOpaqueIIDDADRetries(t *testing.T) { prefix, subnet, _ := prefixSubnetAddr(0, linkAddr1) - for maxRetries := uint8(0); maxRetries <= maxMaxRetries; maxRetries++ { - for numFailures := uint8(0); numFailures <= maxRetries+1; numFailures++ { - addrTypes := []struct { - name string - ndpConfigs stack.NDPConfigurations - autoGenLinkLocal bool - subnet tcpip.Subnet - triggerSLAACFn func(e *channel.Endpoint) - }{ - { - name: "Global address", - ndpConfigs: stack.NDPConfigurations{ - DupAddrDetectTransmits: dadTransmits, - RetransmitTimer: retransmitTimer, - HandleRAs: true, - AutoGenGlobalAddresses: true, - AutoGenAddressConflictRetries: maxRetries, - }, - subnet: subnet, - triggerSLAACFn: func(e *channel.Endpoint) { - // Receive an RA with prefix1 in a PI. - e.InjectInbound(header.IPv6ProtocolNumber, raBufWithPI(llAddr2, 0, prefix, true, true, lifetimeSeconds, lifetimeSeconds)) + addrForSubnet := func(subnet tcpip.Subnet, dadCounter uint8) tcpip.AddressWithPrefix { + addrBytes := []byte(subnet.ID()) + return tcpip.AddressWithPrefix{ + Address: tcpip.Address(header.AppendOpaqueInterfaceIdentifier(addrBytes[:header.IIDOffsetInIPv6Address], subnet, nicName, dadCounter, secretKey)), + PrefixLen: 64, + } + } - }, - }, - { - name: "LinkLocal address", - ndpConfigs: stack.NDPConfigurations{ - DupAddrDetectTransmits: dadTransmits, - RetransmitTimer: retransmitTimer, - AutoGenAddressConflictRetries: maxRetries, - }, - autoGenLinkLocal: true, - subnet: header.IPv6LinkLocalPrefix.Subnet(), - triggerSLAACFn: func(e *channel.Endpoint) {}, - }, + expectAutoGenAddrEvent := func(t *testing.T, ndpDisp *ndpDispatcher, addr tcpip.AddressWithPrefix, eventType ndpAutoGenAddrEventType) { + t.Helper() + + select { + case e := <-ndpDisp.autoGenAddrC: + if diff := checkAutoGenAddrEvent(e, addr, eventType); diff != "" { + t.Errorf("auto-gen addr event mismatch (-want +got):\n%s", diff) } + default: + t.Fatal("expected addr auto gen event") + } + } - for _, addrType := range addrTypes { - maxRetries := maxRetries - numFailures := numFailures - addrType := addrType + expectAutoGenAddrEventAsync := func(t *testing.T, ndpDisp *ndpDispatcher, addr tcpip.AddressWithPrefix, eventType ndpAutoGenAddrEventType) { + t.Helper() - t.Run(fmt.Sprintf("%s with %d max retries and %d failures", addrType.name, maxRetries, numFailures), func(t *testing.T) { - t.Parallel() + select { + case e := <-ndpDisp.autoGenAddrC: + if diff := checkAutoGenAddrEvent(e, addr, eventType); diff != "" { + t.Errorf("auto-gen addr event mismatch (-want +got):\n%s", diff) + } + case <-time.After(defaultAsyncEventTimeout): + t.Fatal("timed out waiting for addr auto gen event") + } + } - ndpDisp := ndpDispatcher{ - dadC: make(chan ndpDADEvent, 1), - autoGenAddrC: make(chan ndpAutoGenAddrEvent, 2), - } - e := channel.New(0, 1280, linkAddr1) - s := stack.New(stack.Options{ - NetworkProtocols: []stack.NetworkProtocol{ipv6.NewProtocol()}, - AutoGenIPv6LinkLocal: addrType.autoGenLinkLocal, - NDPConfigs: addrType.ndpConfigs, - NDPDisp: &ndpDisp, - OpaqueIIDOpts: stack.OpaqueInterfaceIdentifierOptions{ - NICNameFromID: func(_ tcpip.NICID, nicName string) string { - return nicName - }, - SecretKey: secretKey, - }, - }) - opts := stack.NICOptions{Name: nicName} - if err := s.CreateNICWithOptions(nicID, e, opts); err != nil { - t.Fatalf("CreateNICWithOptions(%d, _, %+v) = %s", nicID, opts, err) - } + expectDADEvent := func(t *testing.T, ndpDisp *ndpDispatcher, addr tcpip.Address, resolved bool) { + t.Helper() - expectAutoGenAddrEvent := func(addr tcpip.AddressWithPrefix, eventType ndpAutoGenAddrEventType) { - t.Helper() + select { + case e := <-ndpDisp.dadC: + if diff := checkDADEvent(e, nicID, addr, resolved, nil); diff != "" { + t.Errorf("dad event mismatch (-want +got):\n%s", diff) + } + default: + t.Fatal("expected DAD event") + } + } - select { - case e := <-ndpDisp.autoGenAddrC: - if diff := checkAutoGenAddrEvent(e, addr, eventType); diff != "" { - t.Errorf("auto-gen addr event mismatch (-want +got):\n%s", diff) - } - default: - t.Fatal("expected addr auto gen event") - } - } + expectDADEventAsync := func(t *testing.T, ndpDisp *ndpDispatcher, addr tcpip.Address, resolved bool) { + t.Helper() - addrType.triggerSLAACFn(e) + select { + case e := <-ndpDisp.dadC: + if diff := checkDADEvent(e, nicID, addr, resolved, nil); diff != "" { + t.Errorf("dad event mismatch (-want +got):\n%s", diff) + } + case <-time.After(dadTransmits*retransmitTimer + defaultAsyncEventTimeout): + t.Fatal("timed out waiting for DAD event") + } + } - // Simulate DAD conflicts so the address is regenerated. - for i := uint8(0); i < numFailures; i++ { - addrBytes := []byte(addrType.subnet.ID()) - addr := tcpip.AddressWithPrefix{ - Address: tcpip.Address(header.AppendOpaqueInterfaceIdentifier(addrBytes[:header.IIDOffsetInIPv6Address], addrType.subnet, nicName, i, secretKey)), - PrefixLen: 64, - } - expectAutoGenAddrEvent(addr, newAddr) + stableAddrForTempAddrTest := addrForSubnet(subnet, 0) - // Should not have any addresses assigned to the NIC. - mainAddr, err := s.GetMainNICAddress(nicID, header.IPv6ProtocolNumber) - if err != nil { - t.Fatalf("stack.GetMainNICAddress(%d, _) err = %s", nicID, err) + addrTypes := []struct { + name string + ndpConfigs stack.NDPConfigurations + autoGenLinkLocal bool + prepareFn func(t *testing.T, ndpDisp *ndpDispatcher, e *channel.Endpoint, tempIIDHistory []byte) []tcpip.AddressWithPrefix + addrGenFn func(dadCounter uint8, tempIIDHistory []byte) tcpip.AddressWithPrefix + }{ + { + name: "Global address", + ndpConfigs: stack.NDPConfigurations{ + DupAddrDetectTransmits: dadTransmits, + RetransmitTimer: retransmitTimer, + HandleRAs: true, + AutoGenGlobalAddresses: true, + }, + prepareFn: func(_ *testing.T, _ *ndpDispatcher, e *channel.Endpoint, _ []byte) []tcpip.AddressWithPrefix { + // Receive an RA with prefix1 in a PI. + e.InjectInbound(header.IPv6ProtocolNumber, raBufWithPI(llAddr2, 0, prefix, true, true, lifetimeSeconds, lifetimeSeconds)) + return nil + + }, + addrGenFn: func(dadCounter uint8, _ []byte) tcpip.AddressWithPrefix { + return addrForSubnet(subnet, dadCounter) + }, + }, + { + name: "LinkLocal address", + ndpConfigs: stack.NDPConfigurations{ + DupAddrDetectTransmits: dadTransmits, + RetransmitTimer: retransmitTimer, + }, + autoGenLinkLocal: true, + prepareFn: func(*testing.T, *ndpDispatcher, *channel.Endpoint, []byte) []tcpip.AddressWithPrefix { + return nil + }, + addrGenFn: func(dadCounter uint8, _ []byte) tcpip.AddressWithPrefix { + return addrForSubnet(header.IPv6LinkLocalPrefix.Subnet(), dadCounter) + }, + }, + { + name: "Temporary address", + ndpConfigs: stack.NDPConfigurations{ + DupAddrDetectTransmits: dadTransmits, + RetransmitTimer: retransmitTimer, + HandleRAs: true, + AutoGenGlobalAddresses: true, + AutoGenTempGlobalAddresses: true, + }, + prepareFn: func(t *testing.T, ndpDisp *ndpDispatcher, e *channel.Endpoint, tempIIDHistory []byte) []tcpip.AddressWithPrefix { + header.InitialTempIID(tempIIDHistory, nil, nicID) + + // Generate a stable SLAAC address so temporary addresses will be + // generated. + e.InjectInbound(header.IPv6ProtocolNumber, raBufWithPI(llAddr2, 0, prefix, true, true, 100, 100)) + expectAutoGenAddrEvent(t, ndpDisp, stableAddrForTempAddrTest, newAddr) + expectDADEventAsync(t, ndpDisp, stableAddrForTempAddrTest.Address, true) + + // The stable address will be assigned throughout the test. + return []tcpip.AddressWithPrefix{stableAddrForTempAddrTest} + }, + addrGenFn: func(_ uint8, tempIIDHistory []byte) tcpip.AddressWithPrefix { + return header.GenerateTempIPv6SLAACAddr(tempIIDHistory, stableAddrForTempAddrTest.Address) + }, + }, + } + + for _, addrType := range addrTypes { + // This Run will not return until the parallel tests finish. + // + // We need this because we need to do some teardown work after the parallel + // tests complete and limit the number of parallel tests running at the same + // time to reduce flakes. + // + // See https://godoc.org/testing#hdr-Subtests_and_Sub_benchmarks for + // more details. + t.Run(addrType.name, func(t *testing.T) { + for maxRetries := uint8(0); maxRetries <= maxMaxRetries; maxRetries++ { + for numFailures := uint8(0); numFailures <= maxRetries+1; numFailures++ { + maxRetries := maxRetries + numFailures := numFailures + addrType := addrType + + t.Run(fmt.Sprintf("%d max retries and %d failures", maxRetries, numFailures), func(t *testing.T) { + t.Parallel() + + ndpDisp := ndpDispatcher{ + dadC: make(chan ndpDADEvent, 1), + autoGenAddrC: make(chan ndpAutoGenAddrEvent, 2), } - if want := (tcpip.AddressWithPrefix{}); mainAddr != want { - t.Fatalf("got stack.GetMainNICAddress(_, _) = (%s, nil), want = (%s, nil)", mainAddr, want) + e := channel.New(0, 1280, linkAddr1) + ndpConfigs := addrType.ndpConfigs + ndpConfigs.AutoGenAddressConflictRetries = maxRetries + s := stack.New(stack.Options{ + NetworkProtocols: []stack.NetworkProtocol{ipv6.NewProtocol()}, + AutoGenIPv6LinkLocal: addrType.autoGenLinkLocal, + NDPConfigs: ndpConfigs, + NDPDisp: &ndpDisp, + OpaqueIIDOpts: stack.OpaqueInterfaceIdentifierOptions{ + NICNameFromID: func(_ tcpip.NICID, nicName string) string { + return nicName + }, + SecretKey: secretKey, + }, + }) + opts := stack.NICOptions{Name: nicName} + if err := s.CreateNICWithOptions(nicID, e, opts); err != nil { + t.Fatalf("CreateNICWithOptions(%d, _, %+v) = %s", nicID, opts, err) } - // Simulate a DAD conflict. - if err := s.DupTentativeAddrDetected(nicID, addr.Address); err != nil { - t.Fatalf("s.DupTentativeAddrDetected(%d, %s): %s", nicID, addr.Address, err) - } - expectAutoGenAddrEvent(addr, invalidatedAddr) - select { - case e := <-ndpDisp.dadC: - if diff := checkDADEvent(e, nicID, addr.Address, false, nil); diff != "" { - t.Errorf("dad event mismatch (-want +got):\n%s", diff) + var tempIIDHistory [header.IIDSize]byte + stableAddrs := addrType.prepareFn(t, &ndpDisp, e, tempIIDHistory[:]) + + // Simulate DAD conflicts so the address is regenerated. + for i := uint8(0); i < numFailures; i++ { + addr := addrType.addrGenFn(i, tempIIDHistory[:]) + expectAutoGenAddrEventAsync(t, &ndpDisp, addr, newAddr) + + // Should not have any new addresses assigned to the NIC. + if mismatch := addressCheck(s.NICInfo()[nicID].ProtocolAddresses, stableAddrs, nil); mismatch != "" { + t.Fatal(mismatch) } - default: - t.Fatal("expected DAD event") - } - // Attempting to add the address manually should not fail if the - // address's state was cleaned up when DAD failed. - if err := s.AddAddress(nicID, header.IPv6ProtocolNumber, addr.Address); err != nil { - t.Fatalf("AddAddress(%d, %d, %s) = %s", nicID, header.IPv6ProtocolNumber, addr.Address, err) - } - if err := s.RemoveAddress(nicID, addr.Address); err != nil { - t.Fatalf("RemoveAddress(%d, %s) = %s", nicID, addr.Address, err) - } - select { - case e := <-ndpDisp.dadC: - if diff := checkDADEvent(e, nicID, addr.Address, false, nil); diff != "" { - t.Errorf("dad event mismatch (-want +got):\n%s", diff) + // Simulate a DAD conflict. + if err := s.DupTentativeAddrDetected(nicID, addr.Address); err != nil { + t.Fatalf("s.DupTentativeAddrDetected(%d, %s): %s", nicID, addr.Address, err) } - default: - t.Fatal("expected DAD event") - } - } + expectAutoGenAddrEvent(t, &ndpDisp, addr, invalidatedAddr) + expectDADEvent(t, &ndpDisp, addr.Address, false) - // Should not have any addresses assigned to the NIC. - mainAddr, err := s.GetMainNICAddress(nicID, header.IPv6ProtocolNumber) - if err != nil { - t.Fatalf("stack.GetMainNICAddress(%d, _) err = %s", nicID, err) - } - if want := (tcpip.AddressWithPrefix{}); mainAddr != want { - t.Fatalf("got stack.GetMainNICAddress(_, _) = (%s, nil), want = (%s, nil)", mainAddr, want) - } + // Attempting to add the address manually should not fail if the + // address's state was cleaned up when DAD failed. + if err := s.AddAddress(nicID, header.IPv6ProtocolNumber, addr.Address); err != nil { + t.Fatalf("AddAddress(%d, %d, %s) = %s", nicID, header.IPv6ProtocolNumber, addr.Address, err) + } + if err := s.RemoveAddress(nicID, addr.Address); err != nil { + t.Fatalf("RemoveAddress(%d, %s) = %s", nicID, addr.Address, err) + } + expectDADEvent(t, &ndpDisp, addr.Address, false) + } - // If we had less failures than generation attempts, we should have an - // address after DAD resolves. - if maxRetries+1 > numFailures { - addrBytes := []byte(addrType.subnet.ID()) - addr := tcpip.AddressWithPrefix{ - Address: tcpip.Address(header.AppendOpaqueInterfaceIdentifier(addrBytes[:header.IIDOffsetInIPv6Address], addrType.subnet, nicName, numFailures, secretKey)), - PrefixLen: 64, + // Should not have any new addresses assigned to the NIC. + if mismatch := addressCheck(s.NICInfo()[nicID].ProtocolAddresses, stableAddrs, nil); mismatch != "" { + t.Fatal(mismatch) } - expectAutoGenAddrEvent(addr, newAddr) - select { - case e := <-ndpDisp.dadC: - if diff := checkDADEvent(e, nicID, addr.Address, true, nil); diff != "" { - t.Errorf("dad event mismatch (-want +got):\n%s", diff) + // If we had less failures than generation attempts, we should have + // an address after DAD resolves. + if maxRetries+1 > numFailures { + addr := addrType.addrGenFn(numFailures, tempIIDHistory[:]) + expectAutoGenAddrEventAsync(t, &ndpDisp, addr, newAddr) + expectDADEventAsync(t, &ndpDisp, addr.Address, true) + if mismatch := addressCheck(s.NICInfo()[nicID].ProtocolAddresses, append(stableAddrs, addr), nil); mismatch != "" { + t.Fatal(mismatch) } - case <-time.After(dadTransmits*retransmitTimer + defaultAsyncEventTimeout): - t.Fatal("timed out waiting for DAD event") } - mainAddr, err := s.GetMainNICAddress(nicID, header.IPv6ProtocolNumber) - if err != nil { - t.Fatalf("stack.GetMainNICAddress(%d, _) err = %s", nicID, err) - } - if mainAddr != addr { - t.Fatalf("got stack.GetMainNICAddress(_, _) = (%s, nil), want = (%s, nil)", mainAddr, addr) + // Should not attempt address generation again. + select { + case e := <-ndpDisp.autoGenAddrC: + t.Fatalf("unexpectedly got an auto-generated address event = %+v", e) + case <-time.After(defaultAsyncEventTimeout): } - } - - // Should not attempt address regeneration again. - select { - case e := <-ndpDisp.autoGenAddrC: - t.Fatalf("unexpectedly got an auto-generated address event = %+v", e) - case <-time.After(defaultAsyncEventTimeout): - } - }) + }) + } } - } + }) } } diff --git a/pkg/tcpip/stack/nic.go b/pkg/tcpip/stack/nic.go index 016dbe15e..25188b4fb 100644 --- a/pkg/tcpip/stack/nic.go +++ b/pkg/tcpip/stack/nic.go @@ -131,6 +131,7 @@ func newNIC(stack *Stack, id tcpip.NICID, name string, ep LinkEndpoint, ctx NICC onLinkPrefixes: make(map[tcpip.Subnet]onLinkPrefixState), slaacPrefixes: make(map[tcpip.Subnet]slaacPrefixState), } + nic.mu.ndp.initializeTempAddrState() // Register supported packet endpoint protocols. for _, netProto := range header.Ethertypes { @@ -1014,14 +1015,14 @@ func (n *NIC) removePermanentAddressLocked(addr tcpip.Address) *tcpip.Error { switch r.protocol { case header.IPv6ProtocolNumber: - return n.removePermanentIPv6EndpointLocked(r, true /* allowSLAAPrefixInvalidation */) + return n.removePermanentIPv6EndpointLocked(r, true /* allowSLAACInvalidation */) default: r.expireLocked() return nil } } -func (n *NIC) removePermanentIPv6EndpointLocked(r *referencedNetworkEndpoint, allowSLAACPrefixInvalidation bool) *tcpip.Error { +func (n *NIC) removePermanentIPv6EndpointLocked(r *referencedNetworkEndpoint, allowSLAACInvalidation bool) *tcpip.Error { addr := r.addrWithPrefix() isIPv6Unicast := header.IsV6UnicastAddress(addr.Address) @@ -1031,8 +1032,11 @@ func (n *NIC) removePermanentIPv6EndpointLocked(r *referencedNetworkEndpoint, al // If we are removing an address generated via SLAAC, cleanup // its SLAAC resources and notify the integrator. - if r.configType == slaac { - n.mu.ndp.cleanupSLAACAddrResourcesAndNotify(addr, allowSLAACPrefixInvalidation) + switch r.configType { + case slaac: + n.mu.ndp.cleanupSLAACAddrResourcesAndNotify(addr, allowSLAACInvalidation) + case slaacTemp: + n.mu.ndp.cleanupTempSLAACAddrResourcesAndNotify(addr, allowSLAACInvalidation) } } @@ -1448,12 +1452,19 @@ func (n *NIC) dupTentativeAddrDetected(addr tcpip.Address) *tcpip.Error { // If the address is a SLAAC address, do not invalidate its SLAAC prefix as a // new address will be generated for it. - if err := n.removePermanentIPv6EndpointLocked(ref, false /* allowSLAACPrefixInvalidation */); err != nil { + if err := n.removePermanentIPv6EndpointLocked(ref, false /* allowSLAACInvalidation */); err != nil { return err } - if ref.configType == slaac { - n.mu.ndp.regenerateSLAACAddr(ref.addrWithPrefix().Subnet()) + prefix := ref.addrWithPrefix().Subnet() + + switch ref.configType { + case slaac: + n.mu.ndp.regenerateSLAACAddr(prefix) + case slaacTemp: + // Do not reset the generation attempts counter for the prefix as the + // temporary address is being regenerated in response to a DAD conflict. + n.mu.ndp.regenerateTempSLAACAddr(prefix, false /* resetGenAttempts */) } return nil @@ -1552,9 +1563,14 @@ const ( // multicast group). static networkEndpointConfigType = iota - // A slaac configured endpoint is an IPv6 endpoint that was - // added by SLAAC as per RFC 4862 section 5.5.3. + // A SLAAC configured endpoint is an IPv6 endpoint that was added by + // SLAAC as per RFC 4862 section 5.5.3. slaac + + // A temporary SLAAC configured endpoint is an IPv6 endpoint that was added by + // SLAAC as per RFC 4941. Temporary SLAAC addresses are short-lived and are + // not expected to be valid (or preferred) forever; hence the term temporary. + slaacTemp ) type referencedNetworkEndpoint struct { diff --git a/pkg/tcpip/stack/stack.go b/pkg/tcpip/stack/stack.go index 41398a1b6..4a2dc3dc6 100644 --- a/pkg/tcpip/stack/stack.go +++ b/pkg/tcpip/stack/stack.go @@ -464,6 +464,10 @@ type Stack struct { // (IIDs) as outlined by RFC 7217. opaqueIIDOpts OpaqueInterfaceIdentifierOptions + // tempIIDSeed is used to seed the initial temporary interface identifier + // history value used to generate IIDs for temporary SLAAC addresses. + tempIIDSeed []byte + // forwarder holds the packets that wait for their link-address resolutions // to complete, and forwards them when each resolution is done. forwarder *forwardQueue @@ -541,6 +545,21 @@ type Options struct { // // RandSource must be thread-safe. RandSource mathrand.Source + + // TempIIDSeed is used to seed the initial temporary interface identifier + // history value used to generate IIDs for temporary SLAAC addresses. + // + // Temporary SLAAC adresses are short-lived addresses which are unpredictable + // and random from the perspective of other nodes on the network. It is + // recommended that the seed be a random byte buffer of at least + // header.IIDSize bytes to make sure that temporary SLAAC addresses are + // sufficiently random. It should follow minimum randomness requirements for + // security as outlined by RFC 4086. + // + // Note: using a nil value, the same seed across netstack program runs, or a + // seed that is too small would reduce randomness and increase predictability, + // defeating the purpose of temporary SLAAC addresses. + TempIIDSeed []byte } // TransportEndpointInfo holds useful information about a transport endpoint @@ -664,6 +683,7 @@ func New(opts Options) *Stack { uniqueIDGenerator: opts.UniqueID, ndpDisp: opts.NDPDisp, opaqueIIDOpts: opts.OpaqueIIDOpts, + tempIIDSeed: opts.TempIIDSeed, forwarder: newForwardQueue(), randomGenerator: mathrand.New(randSrc), } |