wire: Treat NetAddress more like immutable

Replace assignments to individual fields of wire.NetAddress with
creating the entire object at once, as one would do if the type was
immutable.

In some places this replaces the creation of a NetAddress with a
high-precision timestamp with a call to a 'constructor' that converts
the timestamp to single second precision. For consistency, the tests
have also been changed to use single-precision timestamps.

Lastly, the number of allocations in readNetAddress have been reduced by
reading the services directly into the NetAddress instead of first into
a temporary variable.

addrmgr/addrmanager.go

@@ -601,18 +601,16 @@ func (a *AddrManager) AddAddressByIP(addrIP string) error {
 		return err
 	}
 	// Put it in wire.Netaddress
-	var na wire.NetAddress
-	na.Timestamp = time.Now()
-	na.IP = net.ParseIP(addr)
-	if na.IP == nil {
+	ip := net.ParseIP(addr)
+	if ip == nil {
 		return fmt.Errorf("invalid ip address %s", addr)
 	}
 	port, err := strconv.ParseUint(portStr, 10, 0)
 	if err != nil {
 		return fmt.Errorf("invalid port %s: %v", portStr, err)
 	}
-	na.Port = uint16(port)
-	a.AddAddress(&na, &na) // XXX use correct src address
+	na := wire.NewNetAddressIPPort(ip, uint16(port), 0)
+	a.AddAddress(na, na) // XXX use correct src address
 	return nil
 }
 
@@ -1074,16 +1072,13 @@ func (a *AddrManager) GetBestLocalAddress(remoteAddr *wire.NetAddress) *wire.Net
 			remoteAddr.Port)
 
 		// Send something unroutable if nothing suitable.
-		bestAddress = &wire.NetAddress{
-			Timestamp: time.Now(),
-			Services:  wire.SFNodeNetwork,
-			Port:      0,
-		}
+		var ip net.IP
 		if !IsIPv4(remoteAddr) && !IsOnionCatTor(remoteAddr) {
-			bestAddress.IP = net.IPv6zero
+			ip = net.IPv6zero
 		} else {
-			bestAddress.IP = net.IPv4zero
+			ip = net.IPv4zero
 		}
+		bestAddress = wire.NewNetAddressIPPort(ip, 0, wire.SFNodeNetwork)
 	}
 
 	return bestAddress

addrmgr/addrmanager_test.go

@@ -94,12 +94,7 @@ func addNaTests() {
 
 func addNaTest(ip string, port uint16, want string) {
 	nip := net.ParseIP(ip)
-	na := wire.NetAddress{
-		Timestamp: time.Now(),
-		Services:  wire.SFNodeNetwork,
-		IP:        nip,
-		Port:      port,
-	}
+	na := *wire.NewNetAddressIPPort(nip, port, wire.SFNodeNetwork)
 	test := naTest{na, want}
 	naTests = append(naTests, test)
 }
@@ -246,7 +241,8 @@ func TestConnected(t *testing.T) {
 	}
 	ka := n.GetAddress()
 	na := ka.NetAddress()
-	na.Timestamp = time.Now().Add(time.Hour * -1) // make it an hour ago
+	// make it an hour ago
+	na.Timestamp = time.Unix(time.Now().Add(time.Hour*-1).Unix(), 0)
 
 	n.Connected(na)
 
@@ -263,7 +259,6 @@ func TestNeedMoreAddresses(t *testing.T) {
 		t.Errorf("Expected that we need more addresses")
 	}
 	addrs := make([]*wire.NetAddress, addrsToAdd)
-	now := time.Now()
 
 	var err error
 	for i := 0; i < addrsToAdd; i++ {
@@ -274,12 +269,7 @@ func TestNeedMoreAddresses(t *testing.T) {
 		}
 	}
 
-	srcAddr := &wire.NetAddress{
-		Timestamp: now,
-		Services:  0,
-		IP:        net.IPv4(173, 144, 173, 111),
-		Port:      8333,
-	}
+	srcAddr := wire.NewNetAddressIPPort(net.IPv4(173, 144, 173, 111), 8333, 0)
 
 	n.AddAddresses(addrs, srcAddr)
 	numAddrs := n.NumAddresses()
@@ -297,7 +287,6 @@ func TestGood(t *testing.T) {
 	n := addrmgr.New("testgood", lookupFunc)
 	addrsToAdd := 64 * 64
 	addrs := make([]*wire.NetAddress, addrsToAdd)
-	now := time.Now()
 
 	var err error
 	for i := 0; i < addrsToAdd; i++ {
@@ -308,12 +297,7 @@ func TestGood(t *testing.T) {
 		}
 	}
 
-	srcAddr := &wire.NetAddress{
-		Timestamp: now,
-		Services:  0,
-		IP:        net.IPv4(173, 144, 173, 111),
-		Port:      8333,
-	}
+	srcAddr := wire.NewNetAddressIPPort(net.IPv4(173, 144, 173, 111), 8333, 0)
 
 	n.AddAddresses(addrs, srcAddr)
 	for _, addr := range addrs {

addrmgr/knownaddress_test.go

@@ -15,33 +15,34 @@ import (
 )
 
 func TestChance(t *testing.T) {
+	now := time.Unix(time.Now().Unix(), 0)
 	var tests = []struct {
 		addr     *addrmgr.KnownAddress
 		expected float64
 	}{
 		{
 			//Test normal case
-			addrmgr.TstNewKnownAddress(&wire.NetAddress{Timestamp: time.Now().Add(-35 * time.Second)},
+			addrmgr.TstNewKnownAddress(&wire.NetAddress{Timestamp: now.Add(-35 * time.Second)},
 				0, time.Now().Add(-30*time.Minute), time.Now(), false, 0),
 			1.0,
 		}, {
 			//Test case in which lastseen < 0
-			addrmgr.TstNewKnownAddress(&wire.NetAddress{Timestamp: time.Now().Add(20 * time.Second)},
+			addrmgr.TstNewKnownAddress(&wire.NetAddress{Timestamp: now.Add(20 * time.Second)},
 				0, time.Now().Add(-30*time.Minute), time.Now(), false, 0),
 			1.0,
 		}, {
 			//Test case in which lastattempt < 0
-			addrmgr.TstNewKnownAddress(&wire.NetAddress{Timestamp: time.Now().Add(-35 * time.Second)},
+			addrmgr.TstNewKnownAddress(&wire.NetAddress{Timestamp: now.Add(-35 * time.Second)},
 				0, time.Now().Add(30*time.Minute), time.Now(), false, 0),
 			1.0 * .01,
 		}, {
 			//Test case in which lastattempt < ten minutes
-			addrmgr.TstNewKnownAddress(&wire.NetAddress{Timestamp: time.Now().Add(-35 * time.Second)},
+			addrmgr.TstNewKnownAddress(&wire.NetAddress{Timestamp: now.Add(-35 * time.Second)},
 				0, time.Now().Add(-5*time.Minute), time.Now(), false, 0),
 			1.0 * .01,
 		}, {
 			//Test case with several failed attempts.
-			addrmgr.TstNewKnownAddress(&wire.NetAddress{Timestamp: time.Now().Add(-35 * time.Second)},
+			addrmgr.TstNewKnownAddress(&wire.NetAddress{Timestamp: now.Add(-35 * time.Second)},
 				2, time.Now().Add(-30*time.Minute), time.Now(), false, 0),
 			1 / 1.5 / 1.5,
 		},
@@ -57,12 +58,13 @@ func TestChance(t *testing.T) {
 }
 
 func TestIsBad(t *testing.T) {
-	future := time.Now().Add(35 * time.Minute)
-	monthOld := time.Now().Add(-43 * time.Hour * 24)
-	secondsOld := time.Now().Add(-2 * time.Second)
-	minutesOld := time.Now().Add(-27 * time.Minute)
-	hoursOld := time.Now().Add(-5 * time.Hour)
-	zeroTime, _ := time.Parse("Jan 1, 1970 at 0:00am (GMT)", "Jan 1, 1970 at 0:00am (GMT)")
+	now := time.Unix(time.Now().Unix(), 0)
+	future := now.Add(35 * time.Minute)
+	monthOld := now.Add(-43 * time.Hour * 24)
+	secondsOld := now.Add(-2 * time.Second)
+	minutesOld := now.Add(-27 * time.Minute)
+	hoursOld := now.Add(-5 * time.Hour)
+	zeroTime := time.Time{}
 
 	futureNa := &wire.NetAddress{Timestamp: future}
 	minutesOldNa := &wire.NetAddress{Timestamp: minutesOld}

addrmgr/network_test.go

@@ -8,7 +8,6 @@ package addrmgr_test
 import (
 	"net"
 	"testing"
-	"time"
 
 	"github.com/decred/dcrd/addrmgr"
 	"github.com/decred/dcrd/wire"
@@ -41,12 +40,7 @@ func TestIPTypes(t *testing.T) {
 		rfc4193, rfc4380, rfc4843, rfc4862, rfc5737, rfc6052, rfc6145, rfc6598,
 		local, valid, routable bool) ipTest {
 		nip := net.ParseIP(ip)
-		na := wire.NetAddress{
-			Timestamp: time.Now(),
-			Services:  wire.SFNodeNetwork,
-			IP:        nip,
-			Port:      8333,
-		}
+		na := *wire.NewNetAddressIPPort(nip, 8333, wire.SFNodeNetwork)
 		test := ipTest{na, rfc1918, rfc2544, rfc3849, rfc3927, rfc3964, rfc4193, rfc4380,
 			rfc4843, rfc4862, rfc5737, rfc6052, rfc6145, rfc6598, local, valid, routable}
 		return test
@@ -199,12 +193,7 @@ func TestGroupKey(t *testing.T) {
 
 	for i, test := range tests {
 		nip := net.ParseIP(test.ip)
-		na := wire.NetAddress{
-			Timestamp: time.Now(),
-			Services:  wire.SFNodeNetwork,
-			IP:        nip,
-			Port:      8333,
-		}
+		na := *wire.NewNetAddressIPPort(nip, 8333, wire.SFNodeNetwork)
 		if key := addrmgr.GroupKey(&na); key != test.expected {
 			t.Errorf("TestGroupKey #%d (%s): unexpected group key "+
 				"- got '%s', want '%s'", i, test.name,

connmgr/seed.go

@@ -50,14 +50,13 @@ func SeedFromDNS(chainParams *chaincfg.Params, lookupFn LookupFunc, seedFn OnSee
 			// if this errors then we have *real* problems
 			intPort, _ := strconv.Atoi(chainParams.DefaultPort)
 			for i, peer := range seedpeers {
-				addresses[i] = new(wire.NetAddress)
-				addresses[i].SetAddress(peer, uint16(intPort))
-				// bitcoind seeds with addresses from
-				// a time randomly selected between 3
-				// and 7 days ago.
-				addresses[i].Timestamp = time.Now().Add(-1 *
-					time.Second * time.Duration(secondsIn3Days+
-					randSource.Int31n(secondsIn4Days)))
+				addresses[i] = wire.NewNetAddressTimestamp(
+					// bitcoind seeds with addresses from
+					// a time randomly selected between 3
+					// and 7 days ago.
+					time.Now().Add(-1*time.Second*time.Duration(secondsIn3Days+
+						randSource.Int31n(secondsIn4Days))),
+					0, peer, uint16(intPort))
 			}
 
 			seedFn(addresses)

peer/peer.go

@@ -761,10 +761,7 @@ func (p *Peer) localVersionMsg() (*wire.MsgVersion, error) {
 		proxyaddress, _, err := net.SplitHostPort(p.cfg.Proxy)
 		// invalid proxy means poorly configured, be on the safe side.
 		if err != nil || p.na.IP.String() == proxyaddress {
-			theirNA = &wire.NetAddress{
-				Timestamp: time.Now(),
-				IP:        net.IP([]byte{0, 0, 0, 0}),
-			}
+			theirNA = wire.NewNetAddressIPPort(net.IP([]byte{0, 0, 0, 0}), 0, 0)
 		}
 	}
 

wire/netaddress.go

@@ -60,20 +60,21 @@ func (na *NetAddress) AddService(service ServiceFlag) {
 	na.Services |= service
 }
 
-// SetAddress is a convenience function to set the IP address and port in one
-// call.
-func (na *NetAddress) SetAddress(ip net.IP, port uint16) {
-	na.IP = ip
-	na.Port = port
-}
-
 // NewNetAddressIPPort returns a new NetAddress using the provided IP, port, and
 // supported services with defaults for the remaining fields.
 func NewNetAddressIPPort(ip net.IP, port uint16, services ServiceFlag) *NetAddress {
+	return NewNetAddressTimestamp(time.Now(), services, ip, port)
+}
+
+// NewNetAddressTimestamp returns a new NetAddress using the provided
+// timestamp, IP, port, and supported services. The timestamp is rounded to
+// single second precision.
+func NewNetAddressTimestamp(
+	timestamp time.Time, services ServiceFlag, ip net.IP, port uint16) *NetAddress {
 	// Limit the timestamp to one second precision since the protocol
 	// doesn't support better.
 	na := NetAddress{
-		Timestamp: time.Unix(time.Now().Unix(), 0),
+		Timestamp: time.Unix(timestamp.Unix(), 0),
 		Services:  services,
 		IP:        ip,
 		Port:      port,
@@ -100,7 +101,6 @@ func NewNetAddress(addr net.Addr, services ServiceFlag) (*NetAddress, error) {
 // version and whether or not the timestamp is included per ts.  Some messages
 // like version do not include the timestamp.
 func readNetAddress(r io.Reader, pver uint32, na *NetAddress, ts bool) error {
-	var services ServiceFlag
 	var ip [16]byte
 
 	// NOTE: The decred protocol uses a uint32 for the timestamp so it will
@@ -113,7 +113,7 @@ func readNetAddress(r io.Reader, pver uint32, na *NetAddress, ts bool) error {
 		}
 	}
 
-	err := readElements(r, &services, &ip)
+	err := readElements(r, &na.Services, &ip)
 	if err != nil {
 		return err
 	}
@@ -123,8 +123,12 @@ func readNetAddress(r io.Reader, pver uint32, na *NetAddress, ts bool) error {
 		return err
 	}
 
-	na.Services = services
-	na.SetAddress(net.IP(ip[:]), port)
+	*na = NetAddress{
+		Timestamp: na.Timestamp,
+		Services:  na.Services,
+		IP:        net.IP(ip[:]),
+		Port:      port,
+	}
 	return nil
 }