Move stack clock to options struct

PiperOrigin-RevId: 207039273
Change-Id: Ib8f55a6dc302052ab4a10ccd70b07f0d73b373df

3 files changed, 29 insertions, 16 deletions

diff --git a/pkg/tcpip/stack/stack.go b/pkg/tcpip/stack/stack.go
index b9d0a1762..9cdc7b6d8 100644
--- a/pkg/tcpip/stack/stack.go
+++ b/pkg/tcpip/stack/stack.go
@@ -285,6 +285,14 @@ type Stack struct {
 	clock tcpip.Clock
 }
 
+// Options contains optional Stack configuration.
+type Options struct {
+	// Clock is an optional clock source used for timestampping packets.
+	//
+	// If no Clock is specified, the clock source will be time.Now.
+	Clock tcpip.Clock
+}
+
 // New allocates a new networking stack with only the requested networking and
 // transport protocols configured with default options.
 //
@@ -292,7 +300,12 @@ type Stack struct {
 // SetNetworkProtocolOption/SetTransportProtocolOption methods provided by the
 // stack. Please refer to individual protocol implementations as to what options
 // are supported.
-func New(clock tcpip.Clock, network []string, transport []string) *Stack {
+func New(network []string, transport []string, opts Options) *Stack {
+	clock := opts.Clock
+	if clock == nil {
+		clock = &tcpip.StdClock{}
+	}
+
 	s := &Stack{
 		transportProtocols: make(map[tcpip.TransportProtocolNumber]*transportProtocolState),
 		networkProtocols:   make(map[tcpip.NetworkProtocolNumber]NetworkProtocol),
diff --git a/pkg/tcpip/stack/stack_test.go b/pkg/tcpip/stack/stack_test.go
index 04806865d..57de5b93a 100644
--- a/pkg/tcpip/stack/stack_test.go
+++ b/pkg/tcpip/stack/stack_test.go
@@ -186,7 +186,7 @@ func TestNetworkReceive(t *testing.T) {
 	// Create a stack with the fake network protocol, one nic, and two
 	// addresses attached to it: 1 & 2.
 	id, linkEP := channel.New(10, defaultMTU, "")
-	s := stack.New(&tcpip.StdClock{}, []string{"fakeNet"}, nil)
+	s := stack.New([]string{"fakeNet"}, nil, stack.Options{})
 	if err := s.CreateNIC(1, id); err != nil {
 		t.Fatalf("CreateNIC failed: %v", err)
 	}
@@ -280,7 +280,7 @@ func TestNetworkSend(t *testing.T) {
 	// address: 1. The route table sends all packets through the only
 	// existing nic.
 	id, linkEP := channel.New(10, defaultMTU, "")
-	s := stack.New(&tcpip.StdClock{}, []string{"fakeNet"}, nil)
+	s := stack.New([]string{"fakeNet"}, nil, stack.Options{})
 	if err := s.CreateNIC(1, id); err != nil {
 		t.Fatalf("NewNIC failed: %v", err)
 	}
@@ -302,7 +302,7 @@ func TestNetworkSendMultiRoute(t *testing.T) {
 	// Create a stack with the fake network protocol, two nics, and two
 	// addresses per nic, the first nic has odd address, the second one has
 	// even addresses.
-	s := stack.New(&tcpip.StdClock{}, []string{"fakeNet"}, nil)
+	s := stack.New([]string{"fakeNet"}, nil, stack.Options{})
 
 	id1, linkEP1 := channel.New(10, defaultMTU, "")
 	if err := s.CreateNIC(1, id1); err != nil {
@@ -381,7 +381,7 @@ func TestRoutes(t *testing.T) {
 	// Create a stack with the fake network protocol, two nics, and two
 	// addresses per nic, the first nic has odd address, the second one has
 	// even addresses.
-	s := stack.New(&tcpip.StdClock{}, []string{"fakeNet"}, nil)
+	s := stack.New([]string{"fakeNet"}, nil, stack.Options{})
 
 	id1, _ := channel.New(10, defaultMTU, "")
 	if err := s.CreateNIC(1, id1); err != nil {
@@ -445,7 +445,7 @@ func TestRoutes(t *testing.T) {
 }
 
 func TestAddressRemoval(t *testing.T) {
-	s := stack.New(&tcpip.StdClock{}, []string{"fakeNet"}, nil)
+	s := stack.New([]string{"fakeNet"}, nil, stack.Options{})
 
 	id, linkEP := channel.New(10, defaultMTU, "")
 	if err := s.CreateNIC(1, id); err != nil {
@@ -489,7 +489,7 @@ func TestAddressRemoval(t *testing.T) {
 }
 
 func TestDelayedRemovalDueToRoute(t *testing.T) {
-	s := stack.New(&tcpip.StdClock{}, []string{"fakeNet"}, nil)
+	s := stack.New([]string{"fakeNet"}, nil, stack.Options{})
 
 	id, linkEP := channel.New(10, defaultMTU, "")
 	if err := s.CreateNIC(1, id); err != nil {
@@ -557,7 +557,7 @@ func TestDelayedRemovalDueToRoute(t *testing.T) {
 }
 
 func TestPromiscuousMode(t *testing.T) {
-	s := stack.New(&tcpip.StdClock{}, []string{"fakeNet"}, nil)
+	s := stack.New([]string{"fakeNet"}, nil, stack.Options{})
 
 	id, linkEP := channel.New(10, defaultMTU, "")
 	if err := s.CreateNIC(1, id); err != nil {
@@ -617,7 +617,7 @@ func TestAddressSpoofing(t *testing.T) {
 	srcAddr := tcpip.Address("\x01")
 	dstAddr := tcpip.Address("\x02")
 
-	s := stack.New(&tcpip.StdClock{}, []string{"fakeNet"}, nil)
+	s := stack.New([]string{"fakeNet"}, nil, stack.Options{})
 
 	id, _ := channel.New(10, defaultMTU, "")
 	if err := s.CreateNIC(1, id); err != nil {
@@ -658,7 +658,7 @@ func TestAddressSpoofing(t *testing.T) {
 
 // Set the subnet, then check that packet is delivered.
 func TestSubnetAcceptsMatchingPacket(t *testing.T) {
-	s := stack.New(&tcpip.StdClock{}, []string{"fakeNet"}, nil)
+	s := stack.New([]string{"fakeNet"}, nil, stack.Options{})
 
 	id, linkEP := channel.New(10, defaultMTU, "")
 	if err := s.CreateNIC(1, id); err != nil {
@@ -692,7 +692,7 @@ func TestSubnetAcceptsMatchingPacket(t *testing.T) {
 
 // Set destination outside the subnet, then check it doesn't get delivered.
 func TestSubnetRejectsNonmatchingPacket(t *testing.T) {
-	s := stack.New(&tcpip.StdClock{}, []string{"fakeNet"}, nil)
+	s := stack.New([]string{"fakeNet"}, nil, stack.Options{})
 
 	id, linkEP := channel.New(10, defaultMTU, "")
 	if err := s.CreateNIC(1, id); err != nil {
@@ -724,7 +724,7 @@ func TestSubnetRejectsNonmatchingPacket(t *testing.T) {
 }
 
 func TestNetworkOptions(t *testing.T) {
-	s := stack.New(&tcpip.StdClock{}, []string{"fakeNet"}, []string{})
+	s := stack.New([]string{"fakeNet"}, []string{}, stack.Options{})
 
 	// Try an unsupported network protocol.
 	if err := s.SetNetworkProtocolOption(tcpip.NetworkProtocolNumber(99999), fakeNetGoodOption(false)); err != tcpip.ErrUnknownProtocol {
diff --git a/pkg/tcpip/stack/transport_test.go b/pkg/tcpip/stack/transport_test.go
index bd0802ccb..98d2f9d99 100644
--- a/pkg/tcpip/stack/transport_test.go
+++ b/pkg/tcpip/stack/transport_test.go
@@ -220,7 +220,7 @@ func (f *fakeTransportProtocol) Option(option interface{}) *tcpip.Error {
 
 func TestTransportReceive(t *testing.T) {
 	id, linkEP := channel.New(10, defaultMTU, "")
-	s := stack.New(&tcpip.StdClock{}, []string{"fakeNet"}, []string{"fakeTrans"})
+	s := stack.New([]string{"fakeNet"}, []string{"fakeTrans"}, stack.Options{})
 	if err := s.CreateNIC(1, id); err != nil {
 		t.Fatalf("CreateNIC failed: %v", err)
 	}
@@ -280,7 +280,7 @@ func TestTransportReceive(t *testing.T) {
 
 func TestTransportControlReceive(t *testing.T) {
 	id, linkEP := channel.New(10, defaultMTU, "")
-	s := stack.New(&tcpip.StdClock{}, []string{"fakeNet"}, []string{"fakeTrans"})
+	s := stack.New([]string{"fakeNet"}, []string{"fakeTrans"}, stack.Options{})
 	if err := s.CreateNIC(1, id); err != nil {
 		t.Fatalf("CreateNIC failed: %v", err)
 	}
@@ -346,7 +346,7 @@ func TestTransportControlReceive(t *testing.T) {
 
 func TestTransportSend(t *testing.T) {
 	id, _ := channel.New(10, defaultMTU, "")
-	s := stack.New(&tcpip.StdClock{}, []string{"fakeNet"}, []string{"fakeTrans"})
+	s := stack.New([]string{"fakeNet"}, []string{"fakeTrans"}, stack.Options{})
 	if err := s.CreateNIC(1, id); err != nil {
 		t.Fatalf("CreateNIC failed: %v", err)
 	}
@@ -383,7 +383,7 @@ func TestTransportSend(t *testing.T) {
 }
 
 func TestTransportOptions(t *testing.T) {
-	s := stack.New(&tcpip.StdClock{}, []string{"fakeNet"}, []string{"fakeTrans"})
+	s := stack.New([]string{"fakeNet"}, []string{"fakeTrans"}, stack.Options{})
 
 	// Try an unsupported transport protocol.
 	if err := s.SetTransportProtocolOption(tcpip.TransportProtocolNumber(99999), fakeTransportGoodOption(false)); err != tcpip.ErrUnknownProtocol {