Merge release-20210112.0-47-g7ff5ceaea (automated)

4 files changed, 29 insertions, 21 deletions

diff --git a/pkg/tcpip/stack/linkaddrcache.go b/pkg/tcpip/stack/linkaddrcache.go
index b600a1cab..3c4fa341e 100644
--- a/pkg/tcpip/stack/linkaddrcache.go
+++ b/pkg/tcpip/stack/linkaddrcache.go
@@ -24,6 +24,8 @@ import (
 
 const linkAddrCacheSize = 512 // max cache entries
 
+var _ LinkAddressCache = (*linkAddrCache)(nil)
+
 // linkAddrCache is a fixed-sized cache mapping IP addresses to link addresses.
 //
 // The entries are stored in a ring buffer, oldest entry replaced first.
@@ -43,7 +45,7 @@ type linkAddrCache struct {
 
 	cache struct {
 		sync.Mutex
-		table map[tcpip.FullAddress]*linkAddrEntry
+		table map[tcpip.Address]*linkAddrEntry
 		lru   linkAddrEntryList
 	}
 }
@@ -81,7 +83,7 @@ type linkAddrEntry struct {
 	// mu protects the fields below.
 	mu sync.RWMutex
 
-	addr       tcpip.FullAddress
+	addr       tcpip.Address
 	linkAddr   tcpip.LinkAddress
 	expiration time.Time
 	s          entryState
@@ -125,7 +127,7 @@ func (e *linkAddrEntry) changeStateLocked(ns entryState, expiration time.Time) {
 }
 
 // add adds a k -> v mapping to the cache.
-func (c *linkAddrCache) add(k tcpip.FullAddress, v tcpip.LinkAddress) {
+func (c *linkAddrCache) AddLinkAddress(k tcpip.Address, v tcpip.LinkAddress) {
 	// Calculate expiration time before acquiring the lock, since expiration is
 	// relative to the time when information was learned, rather than when it
 	// happened to be inserted into the cache.
@@ -150,7 +152,7 @@ func (c *linkAddrCache) add(k tcpip.FullAddress, v tcpip.LinkAddress) {
 // reset to state incomplete, and returned. If no matching entry exists and the
 // cache is not full, a new entry with state incomplete is allocated and
 // returned.
-func (c *linkAddrCache) getOrCreateEntryLocked(k tcpip.FullAddress) *linkAddrEntry {
+func (c *linkAddrCache) getOrCreateEntryLocked(k tcpip.Address) *linkAddrEntry {
 	if entry, ok := c.cache.table[k]; ok {
 		c.cache.lru.Remove(entry)
 		c.cache.lru.PushFront(entry)
@@ -181,7 +183,7 @@ func (c *linkAddrCache) getOrCreateEntryLocked(k tcpip.FullAddress) *linkAddrEnt
 }
 
 // get reports any known link address for k.
-func (c *linkAddrCache) get(k tcpip.FullAddress, linkRes LinkAddressResolver, localAddr tcpip.Address, nic NetworkInterface, onResolve func(tcpip.LinkAddress, bool)) (tcpip.LinkAddress, <-chan struct{}, *tcpip.Error) {
+func (c *linkAddrCache) get(k tcpip.Address, linkRes LinkAddressResolver, localAddr tcpip.Address, nic NetworkInterface, onResolve func(tcpip.LinkAddress, bool)) (tcpip.LinkAddress, <-chan struct{}, *tcpip.Error) {
 	c.cache.Lock()
 	defer c.cache.Unlock()
 	entry := c.getOrCreateEntryLocked(k)
@@ -214,11 +216,11 @@ func (c *linkAddrCache) get(k tcpip.FullAddress, linkRes LinkAddressResolver, lo
 	}
 }
 
-func (c *linkAddrCache) startAddressResolution(k tcpip.FullAddress, linkRes LinkAddressResolver, localAddr tcpip.Address, nic NetworkInterface, done <-chan struct{}) {
+func (c *linkAddrCache) startAddressResolution(k tcpip.Address, linkRes LinkAddressResolver, localAddr tcpip.Address, nic NetworkInterface, done <-chan struct{}) {
 	for i := 0; ; i++ {
 		// Send link request, then wait for the timeout limit and check
 		// whether the request succeeded.
-		linkRes.LinkAddressRequest(k.Addr, localAddr, "" /* linkAddr */, nic)
+		linkRes.LinkAddressRequest(k, localAddr, "" /* linkAddr */, nic)
 
 		select {
 		case now := <-time.After(c.resolutionTimeout):
@@ -234,7 +236,7 @@ func (c *linkAddrCache) startAddressResolution(k tcpip.FullAddress, linkRes Link
 // checkLinkRequest checks whether previous attempt to resolve address has
 // succeeded and mark the entry accordingly. Returns true if request can stop,
 // false if another request should be sent.
-func (c *linkAddrCache) checkLinkRequest(now time.Time, k tcpip.FullAddress, attempt int) bool {
+func (c *linkAddrCache) checkLinkRequest(now time.Time, k tcpip.Address, attempt int) bool {
 	c.cache.Lock()
 	defer c.cache.Unlock()
 	entry, ok := c.cache.table[k]
@@ -268,6 +270,6 @@ func newLinkAddrCache(ageLimit, resolutionTimeout time.Duration, resolutionAttem
 		resolutionTimeout:  resolutionTimeout,
 		resolutionAttempts: resolutionAttempts,
 	}
-	c.cache.table = make(map[tcpip.FullAddress]*linkAddrEntry, linkAddrCacheSize)
+	c.cache.table = make(map[tcpip.Address]*linkAddrEntry, linkAddrCacheSize)
 	return c
 }
diff --git a/pkg/tcpip/stack/nic.go b/pkg/tcpip/stack/nic.go
index 0f545f255..f2bca93d3 100644
--- a/pkg/tcpip/stack/nic.go
+++ b/pkg/tcpip/stack/nic.go
@@ -53,6 +53,8 @@ type NIC struct {
 	// complete.
 	linkResQueue packetsPendingLinkResolution
 
+	linkAddrCache *linkAddrCache
+
 	mu struct {
 		sync.RWMutex
 		spoofing    bool
@@ -137,6 +139,7 @@ func newNIC(stack *Stack, id tcpip.NICID, name string, ep LinkEndpoint, ctx NICC
 		context:          ctx,
 		stats:            makeNICStats(),
 		networkEndpoints: make(map[tcpip.NetworkProtocolNumber]NetworkEndpoint),
+		linkAddrCache:    newLinkAddrCache(ageLimit, resolutionTimeout, resolutionAttempts),
 	}
 	nic.linkResQueue.init()
 	nic.mu.packetEPs = make(map[tcpip.NetworkProtocolNumber]*packetEndpointList)
@@ -167,7 +170,7 @@ func newNIC(stack *Stack, id tcpip.NICID, name string, ep LinkEndpoint, ctx NICC
 	for _, netProto := range stack.networkProtocols {
 		netNum := netProto.Number()
 		nic.mu.packetEPs[netNum] = new(packetEndpointList)
-		nic.networkEndpoints[netNum] = netProto.NewEndpoint(nic, stack, nud, nic)
+		nic.networkEndpoints[netNum] = netProto.NewEndpoint(nic, nic.linkAddrCache, nud, nic)
 	}
 
 	nic.LinkEndpoint.Attach(nic)
@@ -558,7 +561,7 @@ func (n *NIC) getNeighborLinkAddress(addr, localAddr tcpip.Address, linkRes Link
 		return entry.LinkAddr, ch, err
 	}
 
-	return n.stack.linkAddrCache.get(tcpip.FullAddress{NIC: n.ID(), Addr: addr}, linkRes, localAddr, n, onResolve)
+	return n.linkAddrCache.get(addr, linkRes, localAddr, n, onResolve)
 }
 
 func (n *NIC) neighbors() ([]NeighborEntry, *tcpip.Error) {
diff --git a/pkg/tcpip/stack/registration.go b/pkg/tcpip/stack/registration.go
index 34c122728..33df192aa 100644
--- a/pkg/tcpip/stack/registration.go
+++ b/pkg/tcpip/stack/registration.go
@@ -850,7 +850,7 @@ type LinkAddressResolver interface {
 // A LinkAddressCache caches link addresses.
 type LinkAddressCache interface {
 	// AddLinkAddress adds a link address to the cache.
-	AddLinkAddress(nicID tcpip.NICID, addr tcpip.Address, linkAddr tcpip.LinkAddress)
+	AddLinkAddress(addr tcpip.Address, linkAddr tcpip.LinkAddress)
 }
 
 // RawFactory produces endpoints for writing various types of raw packets.
diff --git a/pkg/tcpip/stack/stack.go b/pkg/tcpip/stack/stack.go
index b4878669c..4685fa4cf 100644
--- a/pkg/tcpip/stack/stack.go
+++ b/pkg/tcpip/stack/stack.go
@@ -382,8 +382,6 @@ type Stack struct {
 
 	stats tcpip.Stats
 
-	linkAddrCache *linkAddrCache
-
 	mu   sync.RWMutex
 	nics map[tcpip.NICID]*NIC
 
@@ -636,7 +634,6 @@ func New(opts Options) *Stack {
 		linkAddrResolvers:  make(map[tcpip.NetworkProtocolNumber]LinkAddressResolver),
 		nics:               make(map[tcpip.NICID]*NIC),
 		cleanupEndpoints:   make(map[TransportEndpoint]struct{}),
-		linkAddrCache:      newLinkAddrCache(ageLimit, resolutionTimeout, resolutionAttempts),
 		PortManager:        ports.NewPortManager(),
 		clock:              clock,
 		stats:              opts.Stats.FillIn(),
@@ -1516,12 +1513,18 @@ func (s *Stack) SetSpoofing(nicID tcpip.NICID, enable bool) *tcpip.Error {
 	return nil
 }
 
-// AddLinkAddress adds a link address to the stack link cache.
-func (s *Stack) AddLinkAddress(nicID tcpip.NICID, addr tcpip.Address, linkAddr tcpip.LinkAddress) {
-	fullAddr := tcpip.FullAddress{NIC: nicID, Addr: addr}
-	s.linkAddrCache.add(fullAddr, linkAddr)
-	// TODO: provide a way for a transport endpoint to receive a signal
-	// that AddLinkAddress for a particular address has been called.
+// AddLinkAddress adds a link address for the neighbor on the specified NIC.
+func (s *Stack) AddLinkAddress(nicID tcpip.NICID, neighbor tcpip.Address, linkAddr tcpip.LinkAddress) *tcpip.Error {
+	s.mu.RLock()
+	defer s.mu.RUnlock()
+
+	nic, ok := s.nics[nicID]
+	if !ok {
+		return tcpip.ErrUnknownNICID
+	}
+
+	nic.linkAddrCache.AddLinkAddress(neighbor, linkAddr)
+	return nil
 }
 
 // GetLinkAddress finds the link address corresponding to a neighbor's address.