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Diffstat (limited to 'pkg/tcpip/stack/ndp.go')
-rw-r--r--pkg/tcpip/stack/ndp.go1084
1 files changed, 867 insertions, 217 deletions
diff --git a/pkg/tcpip/stack/ndp.go b/pkg/tcpip/stack/ndp.go
index 045409bda..ae7a8f740 100644
--- a/pkg/tcpip/stack/ndp.go
+++ b/pkg/tcpip/stack/ndp.go
@@ -15,6 +15,7 @@
package stack
import (
+ "fmt"
"log"
"math/rand"
"time"
@@ -118,6 +119,36 @@ 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)
+
+ // maxSLAACAddrLocalRegenAttempts is the maximum number of times to attempt
+ // SLAAC address regenerations in response to a NIC-local conflict.
+ maxSLAACAddrLocalRegenAttempts = 10
)
var (
@@ -130,6 +161,37 @@ 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
@@ -137,9 +199,11 @@ var (
type DHCPv6ConfigurationFromNDPRA int
const (
+ _ DHCPv6ConfigurationFromNDPRA = iota
+
// DHCPv6NoConfiguration indicates that no configurations are available via
// DHCPv6.
- DHCPv6NoConfiguration DHCPv6ConfigurationFromNDPRA = iota
+ DHCPv6NoConfiguration
// DHCPv6ManagedAddress indicates that addresses are available via DHCPv6.
//
@@ -240,12 +304,19 @@ type NDPDispatcher interface {
// call functions on the stack itself.
OnRecursiveDNSServerOption(nicID tcpip.NICID, addrs []tcpip.Address, lifetime time.Duration)
+ // OnDNSSearchListOption will be called when an NDP option with a DNS
+ // search list has been received.
+ //
+ // It is up to the caller to use the domain names in the search list
+ // for only their valid lifetime. OnDNSSearchListOption may be called
+ // with new or already known domain names. If called with known domain
+ // names, their valid lifetimes must be refreshed to lifetime (it may
+ // be increased, decreased or completely invalidated when lifetime = 0.
+ OnDNSSearchListOption(nicID tcpip.NICID, domainNames []string, lifetime time.Duration)
+
// OnDHCPv6Configuration will be called with an updated configuration that is
// available via DHCPv6 for a specified NIC.
//
- // NDPDispatcher assumes that the initial configuration available by DHCPv6 is
- // DHCPv6NoConfiguration.
- //
// This function is not permitted to block indefinitely. It must not
// call functions on the stack itself.
OnDHCPv6Configuration(tcpip.NICID, DHCPv6ConfigurationFromNDPRA)
@@ -304,35 +375,58 @@ type NDPConfigurations struct {
// lifetime(s) of the generated address changes; this option only
// affects the generation of new addresses as part of SLAAC.
AutoGenGlobalAddresses bool
+
+ // AutoGenAddressConflictRetries determines how many times to attempt to retry
+ // generation of a permanent auto-generated address in response to DAD
+ // conflicts.
+ //
+ // If the method used to generate the address does not support creating
+ // 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
@@ -345,6 +439,18 @@ 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.
@@ -361,19 +467,27 @@ 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
+
// The on-link prefixes discovered through Router Advertisements' Prefix
// Information option.
onLinkPrefixes map[tcpip.Subnet]onLinkPrefixState
- // The timer used to send the next router solicitation message.
- // If routers are being solicited, rtrSolicitTimer MUST NOT be nil.
- rtrSolicitTimer *time.Timer
-
- // The addresses generated by SLAAC.
- autoGenAddresses map[tcpip.Address]autoGenAddressState
+ // The SLAAC prefixes discovered through Router Advertisements' Prefix
+ // Information option.
+ slaacPrefixes map[tcpip.Subnet]slaacPrefixState
// 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
@@ -392,28 +506,97 @@ type dadState struct {
// defaultRouterState holds data associated with a default router discovered by
// a Router Advertisement (RA).
type defaultRouterState struct {
- invalidationTimer tcpip.CancellableTimer
+ // Timer to invalidate the default router.
+ //
+ // Must not be nil.
+ invalidationTimer *tcpip.CancellableTimer
}
// 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 {
- invalidationTimer tcpip.CancellableTimer
+ // Timer to invalidate the on-link prefix.
+ //
+ // Must not be nil.
+ invalidationTimer *tcpip.CancellableTimer
}
-// autoGenAddressState holds data associated with an address generated via
-// SLAAC.
-type autoGenAddressState struct {
- // A reference to the referencedNetworkEndpoint that this autoGenAddressState
- // is holding state for.
+// 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
- deprecationTimer tcpip.CancellableTimer
- invalidationTimer tcpip.CancellableTimer
+ // 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.
+ //
+ // Must not be nil.
+ deprecationTimer *tcpip.CancellableTimer
+
+ // Timer to invalidate the prefix.
+ //
+ // Must not be nil.
+ invalidationTimer *tcpip.CancellableTimer
// Nonzero only when the address is not valid forever.
validUntil time.Time
+
+ // Nonzero only when the address is not preferred forever.
+ preferredUntil time.Time
+
+ // State associated with the stable address generated for the prefix.
+ stableAddr struct {
+ // The address's endpoint.
+ //
+ // May only be nil when the address is being (re-)generated. Otherwise,
+ // must not be nil as all SLAAC prefixes must have a stable address.
+ ref *referencedNetworkEndpoint
+
+ // The number of times an address has been generated locally where the NIC
+ // already had the generated address.
+ localGenerationFailures uint8
+ }
+
+ // The temporary (short-lived) addresses generated for the SLAAC prefix.
+ tempAddrs map[tcpip.Address]tempSLAACAddrState
+
+ // 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 and added to the NIC.
+ //
+ // Addresses may be regenerated in reseponse to a DAD conflicts.
+ generationAttempts uint8
+
+ // The maximum number of times to attempt regeneration of a SLAAC address
+ // in response to DAD conflicts.
+ maxGenerationAttempts uint8
}
// startDuplicateAddressDetection performs Duplicate Address Detection.
@@ -430,7 +613,7 @@ func (ndp *ndpState) startDuplicateAddressDetection(addr tcpip.Address, ref *ref
if ref.getKind() != permanentTentative {
// The endpoint should be marked as tentative since we are starting DAD.
- log.Fatalf("ndpdad: addr %s is not tentative on NIC(%d)", addr, ndp.nic.ID())
+ panic(fmt.Sprintf("ndpdad: addr %s is not tentative on NIC(%d)", addr, ndp.nic.ID()))
}
// Should not attempt to perform DAD on an address that is currently in the
@@ -442,7 +625,7 @@ func (ndp *ndpState) startDuplicateAddressDetection(addr tcpip.Address, ref *ref
// address, or its reference count would have been increased without doing
// the work that would have been done for an address that was brand new.
// See NIC.addAddressLocked.
- log.Fatalf("ndpdad: already performing DAD for addr %s on NIC(%d)", addr, ndp.nic.ID())
+ panic(fmt.Sprintf("ndpdad: already performing DAD for addr %s on NIC(%d)", addr, ndp.nic.ID()))
}
remaining := ndp.configs.DupAddrDetectTransmits
@@ -478,7 +661,7 @@ func (ndp *ndpState) startDuplicateAddressDetection(addr tcpip.Address, ref *ref
if ref.getKind() != permanentTentative {
// The endpoint should still be marked as tentative since we are still
// performing DAD on it.
- log.Fatalf("ndpdad: addr %s is no longer tentative on NIC(%d)", addr, ndp.nic.ID())
+ panic(fmt.Sprintf("ndpdad: addr %s is no longer tentative on NIC(%d)", addr, ndp.nic.ID()))
}
dadDone := remaining == 0
@@ -490,10 +673,10 @@ 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
}
@@ -505,8 +688,6 @@ 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
}
@@ -514,15 +695,18 @@ 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{
@@ -548,9 +732,9 @@ func (ndp *ndpState) sendDADPacket(addr tcpip.Address) *tcpip.Error {
// 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 {
- log.Fatalf("ndp: error when resolving route to send NDP NS for DAD (%s -> %s on NIC(%d)): %s", header.IPv6Any, snmc, ndp.nic.ID(), 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 {
- log.Fatalf("ndp: route resolution not immediate for route to send NDP NS for DAD (%s -> %s on NIC(%d))", header.IPv6Any, snmc, ndp.nic.ID())
+ 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)
@@ -566,7 +750,7 @@ func (ndp *ndpState) sendDADPacket(addr tcpip.Address) *tcpip.Error {
Protocol: header.ICMPv6ProtocolNumber,
TTL: header.NDPHopLimit,
TOS: DefaultTOS,
- }, tcpip.PacketBuffer{Header: hdr},
+ }, &PacketBuffer{Header: hdr},
); err != nil {
sent.Dropped.Increment()
return err
@@ -688,7 +872,16 @@ func (ndp *ndpState) handleRA(ip tcpip.Address, ra header.NDPRouterAdvert) {
continue
}
- ndp.nic.stack.ndpDisp.OnRecursiveDNSServerOption(ndp.nic.ID(), opt.Addresses(), opt.Lifetime())
+ addrs, _ := opt.Addresses()
+ ndp.nic.stack.ndpDisp.OnRecursiveDNSServerOption(ndp.nic.ID(), addrs, opt.Lifetime())
+
+ case header.NDPDNSSearchList:
+ if ndp.nic.stack.ndpDisp == nil {
+ continue
+ }
+
+ domainNames, _ := opt.DomainNames()
+ ndp.nic.stack.ndpDisp.OnDNSSearchListOption(ndp.nic.ID(), domainNames, opt.Lifetime())
case header.NDPPrefixInformation:
prefix := opt.Subnet()
@@ -733,7 +926,6 @@ func (ndp *ndpState) invalidateDefaultRouter(ip tcpip.Address) {
}
rtr.invalidationTimer.StopLocked()
-
delete(ndp.defaultRouters, ip)
// Let the integrator know a discovered default router is invalidated.
@@ -762,7 +954,7 @@ func (ndp *ndpState) rememberDefaultRouter(ip tcpip.Address, rl time.Duration) {
}
state := defaultRouterState{
- invalidationTimer: tcpip.MakeCancellableTimer(&ndp.nic.mu, func() {
+ invalidationTimer: tcpip.NewCancellableTimer(&ndp.nic.mu, func() {
ndp.invalidateDefaultRouter(ip)
}),
}
@@ -792,7 +984,7 @@ func (ndp *ndpState) rememberOnLinkPrefix(prefix tcpip.Subnet, l time.Duration)
}
state := onLinkPrefixState{
- invalidationTimer: tcpip.MakeCancellableTimer(&ndp.nic.mu, func() {
+ invalidationTimer: tcpip.NewCancellableTimer(&ndp.nic.mu, func() {
ndp.invalidateOnLinkPrefix(prefix)
}),
}
@@ -817,7 +1009,6 @@ func (ndp *ndpState) invalidateOnLinkPrefix(prefix tcpip.Subnet) {
}
s.invalidationTimer.StopLocked()
-
delete(ndp.onLinkPrefixes, prefix)
// Let the integrator know a discovered on-link prefix is invalidated.
@@ -899,23 +1090,16 @@ func (ndp *ndpState) handleAutonomousPrefixInformation(pi header.NDPPrefixInform
prefix := pi.Subnet()
- // Check if we already have an auto-generated address for prefix.
- for addr, addrState := range ndp.autoGenAddresses {
- refAddrWithPrefix := tcpip.AddressWithPrefix{Address: addr, PrefixLen: addrState.ref.ep.PrefixLen()}
- if refAddrWithPrefix.Subnet() != prefix {
- continue
- }
-
- // At this point, we know we are refreshing a SLAAC generated IPv6 address
- // with the prefix prefix. Do the work as outlined by RFC 4862 section
- // 5.5.3.e.
- ndp.refreshAutoGenAddressLifetimes(addr, pl, vl)
+ // Check if we already maintain SLAAC state for prefix.
+ if state, ok := ndp.slaacPrefixes[prefix]; ok {
+ // As per RFC 4862 section 5.5.3.e, refresh prefix's SLAAC lifetimes.
+ ndp.refreshSLAACPrefixLifetimes(prefix, &state, pl, vl)
+ ndp.slaacPrefixes[prefix] = state
return
}
- // We do not already have an address with the prefix prefix. Do the
- // work as outlined by RFC 4862 section 5.5.3.d if n is configured
- // to auto-generate global addresses by SLAAC.
+ // prefix is a new SLAAC prefix. Do the work as outlined by RFC 4862 section
+ // 5.5.3.d if ndp is configured to auto-generate new addresses via SLAAC.
if !ndp.configs.AutoGenGlobalAddresses {
return
}
@@ -927,6 +1111,8 @@ func (ndp *ndpState) handleAutonomousPrefixInformation(pi header.NDPPrefixInform
// for 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) doSLAAC(prefix tcpip.Subnet, pl, vl time.Duration) {
// If we do not already have an address for this prefix and the valid
// lifetime is 0, no need to do anything further, as per RFC 4862
@@ -942,237 +1128,668 @@ func (ndp *ndpState) doSLAAC(prefix tcpip.Subnet, pl, vl time.Duration) {
return
}
- addrBytes := []byte(prefix.ID())
- if oIID := ndp.nic.stack.opaqueIIDOpts; oIID.NICNameFromID != nil {
- addrBytes = header.AppendOpaqueInterfaceIdentifier(addrBytes[:header.IIDOffsetInIPv6Address], prefix, oIID.NICNameFromID(ndp.nic.ID(), ndp.nic.name), 0 /* dadCounter */, oIID.SecretKey)
- } else {
- // Only attempt to generate an interface-specific IID if we have a valid
- // link address.
- //
- // TODO(b/141011931): Validate a LinkEndpoint's link address (provided by
- // LinkEndpoint.LinkAddress) before reaching this point.
- linkAddr := ndp.nic.linkEP.LinkAddress()
- if !header.IsValidUnicastEthernetAddress(linkAddr) {
- return
- }
+ state := slaacPrefixState{
+ deprecationTimer: tcpip.NewCancellableTimer(&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))
+ }
+
+ ndp.deprecateSLAACAddress(state.stableAddr.ref)
+ }),
+ invalidationTimer: tcpip.NewCancellableTimer(&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))
+ }
- // Generate an address within prefix from the modified EUI-64 of ndp's NIC's
- // Ethernet MAC address.
- header.EthernetAdddressToModifiedEUI64IntoBuf(linkAddr, addrBytes[header.IIDOffsetInIPv6Address:])
+ ndp.invalidateSLAACPrefix(prefix, state)
+ }),
+ tempAddrs: make(map[tcpip.Address]tempSLAACAddrState),
+ maxGenerationAttempts: ndp.configs.AutoGenAddressConflictRetries + 1,
}
- addr := tcpip.Address(addrBytes)
- addrWithPrefix := tcpip.AddressWithPrefix{
- Address: addr,
- PrefixLen: validPrefixLenForAutoGen,
+
+ now := time.Now()
+
+ // The time an address is preferred until is needed to properly generate the
+ // address.
+ if pl < header.NDPInfiniteLifetime {
+ state.preferredUntil = now.Add(pl)
}
- // If the nic already has this address, do nothing further.
- if ndp.nic.hasPermanentAddrLocked(addr) {
+ 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
+ // do not have an address for.
return
}
+ // Setup the initial timers to deprecate and invalidate prefix.
+
+ if pl < header.NDPInfiniteLifetime && pl != 0 {
+ state.deprecationTimer.Reset(pl)
+ }
+
+ if vl < header.NDPInfiniteLifetime {
+ state.invalidationTimer.Reset(vl)
+ state.validUntil = now.Add(vl)
+ }
+
+ // If the address is assigned (DAD resolved), generate a temporary address.
+ if state.stableAddr.ref.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 {
// Inform the integrator that we have a new SLAAC address.
ndpDisp := ndp.nic.stack.ndpDisp
if ndpDisp == nil {
- return
+ return nil
}
- if !ndpDisp.OnAutoGenAddress(ndp.nic.ID(), addrWithPrefix) {
+
+ if !ndpDisp.OnAutoGenAddress(ndp.nic.ID(), addr) {
// Informed by the integrator not to add the address.
- return
+ return nil
}
protocolAddr := tcpip.ProtocolAddress{
Protocol: header.IPv6ProtocolNumber,
- AddressWithPrefix: addrWithPrefix,
+ AddressWithPrefix: addr,
}
- // If the preferred lifetime is zero, then the address should be considered
- // deprecated.
- deprecated := pl == 0
- ref, err := ndp.nic.addAddressLocked(protocolAddr, FirstPrimaryEndpoint, permanent, slaac, deprecated)
+
+ ref, err := ndp.nic.addAddressLocked(protocolAddr, FirstPrimaryEndpoint, permanent, configType, deprecated)
if err != nil {
- log.Fatalf("ndp: error when adding address %s: %s", protocolAddr, err)
+ 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.
+//
+// Panics if the prefix is not a SLAAC prefix or it already has an address.
+//
+// The NIC that ndp belongs to MUST be locked.
+func (ndp *ndpState) generateSLAACAddr(prefix tcpip.Subnet, state *slaacPrefixState) bool {
+ if r := state.stableAddr.ref; r != nil {
+ panic(fmt.Sprintf("ndp: SLAAC prefix %s already has a permenant address %s", prefix, r.addrWithPrefix()))
+ }
+
+ // If we have already reached the maximum address generation attempts for the
+ // prefix, do not generate another address.
+ if state.generationAttempts == state.maxGenerationAttempts {
+ return false
+ }
+
+ var generatedAddr tcpip.AddressWithPrefix
+ addrBytes := []byte(prefix.ID())
+
+ for i := 0; ; i++ {
+ // If we were unable to generate an address after the maximum SLAAC address
+ // local regeneration attempts, do nothing further.
+ if i == maxSLAACAddrLocalRegenAttempts {
+ return false
+ }
+
+ dadCounter := state.generationAttempts + state.stableAddr.localGenerationFailures
+ if oIID := ndp.nic.stack.opaqueIIDOpts; oIID.NICNameFromID != nil {
+ addrBytes = header.AppendOpaqueInterfaceIdentifier(
+ addrBytes[:header.IIDOffsetInIPv6Address],
+ prefix,
+ oIID.NICNameFromID(ndp.nic.ID(), ndp.nic.name),
+ dadCounter,
+ oIID.SecretKey,
+ )
+ } else if dadCounter == 0 {
+ // Modified-EUI64 based IIDs have no way to resolve DAD conflicts, so if
+ // the DAD counter is non-zero, we cannot use this method.
+ //
+ // Only attempt to generate an interface-specific IID if we have a valid
+ // link address.
+ //
+ // TODO(b/141011931): Validate a LinkEndpoint's link address (provided by
+ // LinkEndpoint.LinkAddress) before reaching this point.
+ linkAddr := ndp.nic.linkEP.LinkAddress()
+ if !header.IsValidUnicastEthernetAddress(linkAddr) {
+ return false
+ }
+
+ // Generate an address within prefix from the modified EUI-64 of ndp's
+ // NIC's Ethernet MAC address.
+ header.EthernetAdddressToModifiedEUI64IntoBuf(linkAddr, addrBytes[header.IIDOffsetInIPv6Address:])
+ } else {
+ // We have no way to regenerate an address in response to an address
+ // conflict when addresses are not generated with opaque IIDs.
+ return false
+ }
+
+ generatedAddr = tcpip.AddressWithPrefix{
+ Address: tcpip.Address(addrBytes),
+ PrefixLen: validPrefixLenForAutoGen,
+ }
+
+ if !ndp.nic.hasPermanentAddrLocked(generatedAddr.Address) {
+ break
+ }
+
+ state.stableAddr.localGenerationFailures++
+ }
+
+ if ref := ndp.addSLAACAddr(generatedAddr, slaac, time.Since(state.preferredUntil) >= 0 /* deprecated */); ref != nil {
+ state.stableAddr.ref = ref
+ state.generationAttempts++
+ return true
+ }
+
+ return false
+}
+
+// regenerateSLAACAddr regenerates an address for a SLAAC prefix.
+//
+// If generating a new address for the prefix fails, the prefix will be
+// invalidated.
+//
+// The NIC that ndp belongs to MUST be locked.
+func (ndp *ndpState) regenerateSLAACAddr(prefix tcpip.Subnet) {
+ state, ok := ndp.slaacPrefixes[prefix]
+ if !ok {
+ panic(fmt.Sprintf("ndp: SLAAC prefix state not found to regenerate address for %s", prefix))
+ }
+
+ if ndp.generateSLAACAddr(prefix, &state) {
+ ndp.slaacPrefixes[prefix] = state
+ return
+ }
+
+ // We were unable to generate a permanent address for the SLAAC prefix so
+ // invalidate the prefix as there is no reason to maintain state for a
+ // SLAAC prefix we do not have an address for.
+ ndp.invalidateSLAACPrefix(prefix, state)
+}
+
+// generateTempSLAACAddr generates a new temporary SLAAC address.
+//
+// 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.stableAddr.ref.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
+ }
}
- state := autoGenAddressState{
- ref: ref,
- deprecationTimer: tcpip.MakeCancellableTimer(&ndp.nic.mu, func() {
- addrState, ok := ndp.autoGenAddresses[addr]
+ // 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
+ }
+
+ // Attempt to generate a new address that is not already assigned to the NIC.
+ var generatedAddr tcpip.AddressWithPrefix
+ for i := 0; ; i++ {
+ // If we were unable to generate an address after the maximum SLAAC address
+ // local regeneration attempts, do nothing further.
+ if i == maxSLAACAddrLocalRegenAttempts {
+ return false
+ }
+
+ generatedAddr = header.GenerateTempIPv6SLAACAddr(ndp.temporaryIIDHistory[:], stableAddr)
+ if !ndp.nic.hasPermanentAddrLocked(generatedAddr.Address) {
+ break
+ }
+ }
+
+ // 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 {
- log.Fatalf("ndp: must have an autoGenAddressess entry for the SLAAC generated IPv6 address %s", addr)
+ panic(fmt.Sprintf("ndp: must have a tempAddr entry to deprecate temporary address %s", generatedAddr))
}
- addrState.ref.deprecated = true
- ndp.notifyAutoGenAddressDeprecated(addr)
+
+ ndp.deprecateSLAACAddress(tempAddrState.ref)
}),
- invalidationTimer: tcpip.MakeCancellableTimer(&ndp.nic.mu, func() {
- ndp.invalidateAutoGenAddress(addr)
+ 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))
+ }
- // Setup the initial timers to deprecate and invalidate this newly generated
- // address.
+ 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 !deprecated && pl < header.NDPInfiniteLifetime {
- state.deprecationTimer.Reset(pl)
- }
+ // If an address has already been regenerated for this address, don't
+ // regenerate another address.
+ if tempAddrState.regenerated {
+ return
+ }
- if vl < header.NDPInfiniteLifetime {
- state.invalidationTimer.Reset(vl)
- state.validUntil = time.Now().Add(vl)
+ // 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,
}
- ndp.autoGenAddresses[addr] = state
+ state.deprecationTimer.Reset(pl)
+ state.invalidationTimer.Reset(vl)
+ state.regenTimer.Reset(pl - ndp.configs.RegenAdvanceDuration)
+
+ prefixState.generationAttempts++
+ prefixState.tempAddrs[generatedAddr.Address] = state
+
+ return true
}
-// refreshAutoGenAddressLifetimes refreshes the lifetime of a SLAAC generated
-// address addr.
+// regenerateTempSLAACAddr regenerates a temporary address for a SLAAC prefix.
//
-// pl is the new preferred lifetime. vl is the new valid lifetime.
-func (ndp *ndpState) refreshAutoGenAddressLifetimes(addr tcpip.Address, pl, vl time.Duration) {
- addrState, ok := ndp.autoGenAddresses[addr]
+// The NIC that ndp belongs to MUST be locked.
+func (ndp *ndpState) regenerateTempSLAACAddr(prefix tcpip.Subnet, resetGenAttempts bool) {
+ state, ok := ndp.slaacPrefixes[prefix]
if !ok {
- log.Fatalf("ndp: SLAAC state not found to refresh lifetimes for %s", addr)
+ panic(fmt.Sprintf("ndp: SLAAC prefix state not found to regenerate temporary address for %s", prefix))
}
- defer func() { ndp.autoGenAddresses[addr] = addrState }()
- // If the preferred lifetime is zero, then the address should be considered
- // deprecated.
- deprecated := pl == 0
- wasDeprecated := addrState.ref.deprecated
- addrState.ref.deprecated = deprecated
+ ndp.generateTempSLAACAddr(prefix, &state, resetGenAttempts)
+ ndp.slaacPrefixes[prefix] = state
+}
- // Only send the deprecation event if the deprecated status for addr just
- // changed from non-deprecated to deprecated.
- if !wasDeprecated && deprecated {
- ndp.notifyAutoGenAddressDeprecated(addr)
+// 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.stableAddr.ref)
+ } else {
+ prefixState.stableAddr.ref.deprecated = false
}
- // If addr was preferred for some finite lifetime before, stop the deprecation
- // timer so it can be reset.
- addrState.deprecationTimer.StopLocked()
+ // If prefix was preferred for some finite lifetime before, stop the
+ // deprecation timer so it can be reset.
+ prefixState.deprecationTimer.StopLocked()
- // Reset the deprecation timer if addr has a finite preferred lifetime.
- if !deprecated && pl < header.NDPInfiniteLifetime {
- addrState.deprecationTimer.Reset(pl)
+ now := time.Now()
+
+ // Reset the deprecation timer if prefix has a finite preferred lifetime.
+ if pl < header.NDPInfiniteLifetime {
+ if !deprecated {
+ prefixState.deprecationTimer.Reset(pl)
+ }
+ prefixState.preferredUntil = now.Add(pl)
+ } else {
+ prefixState.preferredUntil = time.Time{}
}
- // As per RFC 4862 section 5.5.3.e, the valid lifetime of the address
- //
+ // As per RFC 4862 section 5.5.3.e, update the valid lifetime for prefix:
//
// 1) If the received Valid Lifetime is greater than 2 hours or greater than
- // RemainingLifetime, set the valid lifetime of the address to the
+ // RemainingLifetime, set the valid lifetime of the prefix to the
// advertised Valid Lifetime.
//
// 2) If RemainingLifetime is less than or equal to 2 hours, ignore the
// advertised Valid Lifetime.
//
- // 3) Otherwise, reset the valid lifetime of the address to 2 hours.
+ // 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 {
- addrState.invalidationTimer.StopLocked()
- addrState.validUntil = time.Time{}
+ // Handle the infinite valid lifetime separately as we do not keep a timer
+ // in this case.
+ prefixState.invalidationTimer.StopLocked()
+ prefixState.validUntil = time.Time{}
+ } 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)
+ }
+
+ if vl > MinPrefixInformationValidLifetimeForUpdate || vl > rl {
+ effectiveVl = vl
+ } else if rl > MinPrefixInformationValidLifetimeForUpdate {
+ effectiveVl = MinPrefixInformationValidLifetimeForUpdate
+ }
+
+ if effectiveVl != 0 {
+ prefixState.invalidationTimer.StopLocked()
+ prefixState.invalidationTimer.Reset(effectiveVl)
+ prefixState.validUntil = now.Add(effectiveVl)
+ }
+ }
+
+ // If DAD is not yet complete on the stable address, there is no need to do
+ // work with temporary addresses.
+ if prefixState.stableAddr.ref.getKind() != permanent {
return
}
- var effectiveVl time.Duration
- var rl time.Duration
+ // 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 was originally set to be valid forever, assume the remaining
- // time to be the maximum possible value.
- if addrState.validUntil == (time.Time{}) {
- rl = header.NDPInfiniteLifetime
- } else {
- rl = time.Until(addrState.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)
+ }
+ }
}
- if vl > MinPrefixInformationValidLifetimeForUpdate || vl > rl {
- effectiveVl = vl
- } else if rl <= MinPrefixInformationValidLifetimeForUpdate {
+ // 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
+// dispatcher that ref has been deprecated.
+//
+// deprecateSLAACAddress does nothing if ref is already deprecated.
+//
+// The NIC that ndp belongs to MUST be locked.
+func (ndp *ndpState) deprecateSLAACAddress(ref *referencedNetworkEndpoint) {
+ if ref.deprecated {
return
- } else {
- effectiveVl = MinPrefixInformationValidLifetimeForUpdate
}
- addrState.invalidationTimer.StopLocked()
- addrState.invalidationTimer.Reset(effectiveVl)
- addrState.validUntil = time.Now().Add(effectiveVl)
+ ref.deprecated = true
+ if ndpDisp := ndp.nic.stack.ndpDisp; ndpDisp != nil {
+ ndpDisp.OnAutoGenAddressDeprecated(ndp.nic.ID(), ref.addrWithPrefix())
+ }
}
-// notifyAutoGenAddressDeprecated notifies the stack's NDP dispatcher that addr
-// has been deprecated.
-func (ndp *ndpState) notifyAutoGenAddressDeprecated(addr tcpip.Address) {
- if ndpDisp := ndp.nic.stack.ndpDisp; ndpDisp != nil {
- ndpDisp.OnAutoGenAddressDeprecated(ndp.nic.ID(), tcpip.AddressWithPrefix{
- Address: addr,
- PrefixLen: validPrefixLenForAutoGen,
- })
+// invalidateSLAACPrefix invalidates a SLAAC prefix.
+//
+// The NIC that ndp belongs to MUST be locked.
+func (ndp *ndpState) invalidateSLAACPrefix(prefix tcpip.Subnet, state slaacPrefixState) {
+ if r := state.stableAddr.ref; 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 /* allowSLAACInvalidation */); err != nil {
+ panic(fmt.Sprintf("ndp: error removing stable SLAAC address %s: %s", r.addrWithPrefix(), err))
+ }
}
+
+ ndp.cleanupSLAACPrefixResources(prefix, state)
}
-// invalidateAutoGenAddress invalidates an auto-generated address.
+// cleanupSLAACAddrResourcesAndNotify cleans up an invalidated SLAAC address's
+// resources.
//
// The NIC that ndp belongs to MUST be locked.
-func (ndp *ndpState) invalidateAutoGenAddress(addr tcpip.Address) {
- if !ndp.cleanupAutoGenAddrResourcesAndNotify(addr) {
+func (ndp *ndpState) cleanupSLAACAddrResourcesAndNotify(addr tcpip.AddressWithPrefix, invalidatePrefix bool) {
+ if ndpDisp := ndp.nic.stack.ndpDisp; ndpDisp != nil {
+ ndpDisp.OnAutoGenAddressInvalidated(ndp.nic.ID(), addr)
+ }
+
+ prefix := addr.Subnet()
+ state, ok := ndp.slaacPrefixes[prefix]
+ if !ok || state.stableAddr.ref == nil || addr.Address != state.stableAddr.ref.ep.ID().LocalAddress {
return
}
- ndp.nic.removePermanentAddressLocked(addr)
+ if !invalidatePrefix {
+ // If the prefix is not being invalidated, disassociate the address from the
+ // prefix and do nothing further.
+ state.stableAddr.ref = nil
+ ndp.slaacPrefixes[prefix] = state
+ return
+ }
+
+ ndp.cleanupSLAACPrefixResources(prefix, state)
}
-// cleanupAutoGenAddrResourcesAndNotify cleans up an invalidated auto-generated
-// address's resources from ndp. If the stack has an NDP dispatcher, it will
-// be notified that addr has been invalidated.
+// cleanupSLAACPrefixResources cleansup a SLAAC prefix's timers and entry.
//
-// Returns true if ndp had resources for addr to cleanup.
+// Panics if the SLAAC prefix is not known.
//
// The NIC that ndp belongs to MUST be locked.
-func (ndp *ndpState) cleanupAutoGenAddrResourcesAndNotify(addr tcpip.Address) bool {
- state, ok := ndp.autoGenAddresses[addr]
- if !ok {
- return false
+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.stableAddr.ref = nil
state.deprecationTimer.StopLocked()
state.invalidationTimer.StopLocked()
- delete(ndp.autoGenAddresses, addr)
+ 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(), tcpip.AddressWithPrefix{
- Address: addr,
- PrefixLen: validPrefixLenForAutoGen,
- })
+ ndpDisp.OnAutoGenAddressInvalidated(ndp.nic.ID(), addr)
}
- return true
+ 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)
}
-// cleanupHostOnlyState cleans up any state that is only useful for hosts.
+// cleanupState cleans up ndp's state.
+//
+// If hostOnly is true, then only host-specific state will be cleaned up.
//
-// cleanupHostOnlyState MUST be called when ndp's NIC is transitioning from a
-// host to a router. This function will invalidate all discovered on-link
-// prefixes, discovered routers, and auto-generated addresses as routers do not
-// normally process Router Advertisements to discover default routers and
-// on-link prefixes, and auto-generate addresses via SLAAC.
+// cleanupState MUST be called with hostOnly set to true when ndp's NIC is
+// transitioning from a host to a router. This function will invalidate all
+// discovered on-link prefixes, discovered routers, and auto-generated
+// addresses.
+//
+// If hostOnly is true, then the link-local auto-generated address will not be
+// invalidated as routers are also expected to generate a link-local address.
//
// The NIC that ndp belongs to MUST be locked.
-func (ndp *ndpState) cleanupHostOnlyState() {
+func (ndp *ndpState) cleanupState(hostOnly bool) {
linkLocalSubnet := header.IPv6LinkLocalPrefix.Subnet()
- linkLocalAddrs := 0
- for addr := range ndp.autoGenAddresses {
+ linkLocalPrefixes := 0
+ for prefix, state := range ndp.slaacPrefixes {
// RFC 4862 section 5 states that routers are also expected to generate a
- // link-local address so we do not invalidate them.
- if linkLocalSubnet.Contains(addr) {
- linkLocalAddrs++
+ // link-local address so we do not invalidate them if we are cleaning up
+ // host-only state.
+ if hostOnly && prefix == linkLocalSubnet {
+ linkLocalPrefixes++
continue
}
- ndp.invalidateAutoGenAddress(addr)
+ ndp.invalidateSLAACPrefix(prefix, state)
}
- if got := len(ndp.autoGenAddresses); got != linkLocalAddrs {
- log.Fatalf("ndp: still have non-linklocal auto-generated addresses after cleaning up; found = %d prefixes, of which %d are link-local", got, linkLocalAddrs)
+ if got := len(ndp.slaacPrefixes); got != linkLocalPrefixes {
+ panic(fmt.Sprintf("ndp: still have non-linklocal SLAAC prefixes after cleaning up; found = %d prefixes, of which %d are link-local", got, linkLocalPrefixes))
}
for prefix := range ndp.onLinkPrefixes {
@@ -1180,7 +1797,7 @@ func (ndp *ndpState) cleanupHostOnlyState() {
}
if got := len(ndp.onLinkPrefixes); got != 0 {
- log.Fatalf("ndp: still have discovered on-link prefixes after cleaning up; found = %d", got)
+ panic(fmt.Sprintf("ndp: still have discovered on-link prefixes after cleaning up; found = %d", got))
}
for router := range ndp.defaultRouters {
@@ -1188,8 +1805,10 @@ func (ndp *ndpState) cleanupHostOnlyState() {
}
if got := len(ndp.defaultRouters); got != 0 {
- log.Fatalf("ndp: still have discovered default routers after cleaning up; found = %d", got)
+ panic(fmt.Sprintf("ndp: still have discovered default routers after cleaning up; found = %d", got))
}
+
+ ndp.dhcpv6Configuration = 0
}
// startSolicitingRouters starts soliciting routers, as per RFC 4861 section
@@ -1215,24 +1834,45 @@ func (ndp *ndpState) startSolicitingRouters() {
}
ndp.rtrSolicitTimer = time.AfterFunc(delay, func() {
- // Send an RS message with the unspecified source address.
- ref := ndp.nic.getRefOrCreateTemp(header.IPv6ProtocolNumber, header.IPv6Any, NeverPrimaryEndpoint, forceSpoofing)
- r := makeRoute(header.IPv6ProtocolNumber, header.IPv6Any, header.IPv6AllRoutersMulticastAddress, ndp.nic.linkEP.LinkAddress(), ref, false, false)
+ // 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)
+ if ref == nil {
+ ref = ndp.nic.getRefOrCreateTemp(header.IPv6ProtocolNumber, header.IPv6Any, NeverPrimaryEndpoint, forceSpoofing)
+ }
+ localAddr := ref.ep.ID().LocalAddress
+ r := makeRoute(header.IPv6ProtocolNumber, localAddr, header.IPv6AllRoutersMulticastAddress, ndp.nic.linkEP.LinkAddress(), ref, false, false)
defer r.Release()
// Route should resolve immediately since
// 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 {
- log.Fatalf("ndp: error when resolving route to send NDP RS (%s -> %s on NIC(%d)): %s", header.IPv6Any, header.IPv6AllRoutersMulticastAddress, ndp.nic.ID(), err)
+ 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 {
- log.Fatalf("ndp: route resolution not immediate for route to send NDP RS (%s -> %s on NIC(%d))", header.IPv6Any, header.IPv6AllRoutersMulticastAddress, ndp.nic.ID())
+ 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()))
}
- payloadSize := header.ICMPv6HeaderSize + header.NDPRSMinimumSize
- hdr := buffer.NewPrependable(header.IPv6MinimumSize + payloadSize)
+ // As per RFC 4861 section 4.1, an NDP RS SHOULD include the source
+ // link-layer address option if the source address of the NDP RS is
+ // specified. This option MUST NOT be included if the source address is
+ // unspecified.
+ //
+ // TODO(b/141011931): Validate a LinkEndpoint's link address (provided by
+ // LinkEndpoint.LinkAddress) before reaching this point.
+ var optsSerializer header.NDPOptionsSerializer
+ if localAddr != header.IPv6Any && header.IsValidUnicastEthernetAddress(r.LocalLinkAddress) {
+ optsSerializer = header.NDPOptionsSerializer{
+ header.NDPSourceLinkLayerAddressOption(r.LocalLinkAddress),
+ }
+ }
+ 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())
+ rs.Options().Serialize(optsSerializer)
pkt.SetChecksum(header.ICMPv6Checksum(pkt, r.LocalAddress, r.RemoteAddress, buffer.VectorisedView{}))
sent := r.Stats().ICMP.V6PacketsSent
@@ -1241,7 +1881,7 @@ func (ndp *ndpState) startSolicitingRouters() {
Protocol: header.ICMPv6ProtocolNumber,
TTL: header.NDPHopLimit,
TOS: DefaultTOS,
- }, tcpip.PacketBuffer{Header: hdr},
+ }, &PacketBuffer{Header: hdr},
); err != nil {
sent.Dropped.Increment()
log.Printf("startSolicitingRouters: error writing NDP router solicit message on NIC(%d); err = %s", ndp.nic.ID(), err)
@@ -1281,3 +1921,13 @@ 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)))
+ }
+}