Added constants where necessary.

pkg/router/route_manager.go

@@ -35,7 +35,9 @@ func (rm *routeManager) GetRule(routeID routing.RouteID) (routing.Rule, error) {
 		return nil, errors.New("unknown RouteID")
 	}
 
-	if len(rule) < 13 {
+	// TODO(evanlinjin): This is a workaround for ensuring the read-in rule is of the correct size.
+	// Sometimes it is not, causing a segfault later down the line.
+	if len(rule) < routing.RuleHeaderSize {
 		return nil, errors.New("corrupted rule")
 	}
 

pkg/routing/packet.go

@@ -5,6 +5,11 @@ import (
 	"math"
 )
 
+// PacketHeaderSize represents the base size of a packet.
+// All rules should have at-least this size.
+// TODO(evanlinjin): Document the format of packets in comments.
+const PacketHeaderSize = 6
+
 // RouteID represents ID of a Route in a Packet.
 type RouteID uint32
 
@@ -18,7 +23,7 @@ func MakePacket(id RouteID, payload []byte) Packet {
 		panic("packet size exceeded")
 	}
 
-	packet := make([]byte, 6)
+	packet := make([]byte, PacketHeaderSize)
 	binary.BigEndian.PutUint16(packet, uint16(len(payload)))
 	binary.BigEndian.PutUint32(packet[2:], uint32(id))
 	return Packet(append(packet, payload...))
@@ -36,5 +41,5 @@ func (p Packet) RouteID() RouteID {
 
 // Payload returns payload from a Packet.
 func (p Packet) Payload() []byte {
-	return p[6:]
+	return p[PacketHeaderSize:]
 }

pkg/routing/rule.go

@@ -10,6 +10,11 @@ import (
 	"github.com/skycoin/dmsg/cipher"
 )
 
+// RuleHeaderSize represents the base size of a rule.
+// All rules should be at-least this size.
+// TODO(evanlinjin): Document the format of rules in comments.
+const RuleHeaderSize = 13
+
 // RuleType defines type of a routing rule
 type RuleType byte
 
@@ -164,7 +169,7 @@ func (r Rule) Summary() *RuleSummary {
 
 // AppRule constructs a new consume RoutingRule.
 func AppRule(expireAt time.Time, respRoute RouteID, remotePK cipher.PubKey, remotePort, localPort Port) Rule {
-	rule := make([]byte, 13)
+	rule := make([]byte, RuleHeaderSize)
 	if expireAt.Unix() <= time.Now().Unix() {
 		binary.BigEndian.PutUint64(rule[0:], 0)
 	} else {
@@ -182,7 +187,7 @@ func AppRule(expireAt time.Time, respRoute RouteID, remotePK cipher.PubKey, remo
 
 // ForwardRule constructs a new forward RoutingRule.
 func ForwardRule(expireAt time.Time, nextRoute RouteID, nextTrID uuid.UUID) Rule {
-	rule := make([]byte, 13)
+	rule := make([]byte, RuleHeaderSize)
 	if expireAt.Unix() <= time.Now().Unix() {
 		binary.BigEndian.PutUint64(rule[0:], 0)
 	} else {

pkg/setup/config.go

@@ -1,9 +1,17 @@
 package setup
 
 import (
+	"time"
+
 	"github.com/skycoin/dmsg/cipher"
 )
 
+// Various timeouts for setup node.
+const (
+	ServeTransportTimeout = time.Second * 30
+	ReadTimeout           = time.Second * 10
+)
+
 // Config defines configuration parameters for setup Node.
 type Config struct {
 	PubKey cipher.PubKey `json:"public_key"`

pkg/setup/node.go

@@ -75,7 +75,7 @@ func (sn *Node) Serve(ctx context.Context) error {
 }
 
 func (sn *Node) serveTransport(ctx context.Context, tr transport.Transport) error {
-	ctx, cancel := context.WithTimeout(ctx, time.Second*30)
+	ctx, cancel := context.WithTimeout(ctx, ServeTransportTimeout)
 	defer cancel()
 
 	proto := NewSetupProtocol(tr)

pkg/setup/protocol.go

@@ -8,7 +8,6 @@ import (
 	"errors"
 	"fmt"
 	"io"
-	"time"
 
 	"github.com/skycoin/skywire/pkg/routing"
 )
@@ -164,7 +163,7 @@ func LoopClosed(ctx context.Context, p *Protocol, ld routing.LoopData) error {
 }
 
 func readAndDecodePacketWithTimeout(ctx context.Context, p *Protocol, v interface{}) error {
-	ctx, cancel := context.WithTimeout(ctx, time.Second*10)
+	ctx, cancel := context.WithTimeout(ctx, ReadTimeout)
 	defer cancel()
 
 	done := make(chan struct{})

pkg/transport/managed_transport.go

@@ -296,8 +296,8 @@ func (mt *ManagedTransport) WritePacket(ctx context.Context, rtID routing.RouteI
 		mt.clearConn(ctx)
 		return err
 	}
-	if n > 6 {
-		mt.logSent(uint64(n - 6))
+	if n > routing.PacketHeaderSize {
+		mt.logSent(uint64(n - routing.PacketHeaderSize))
 	}
 	return nil
 }
@@ -316,7 +316,7 @@ func (mt *ManagedTransport) readPacket() (packet routing.Packet, err error) {
 		}
 	}
 
-	h := make(routing.Packet, 6)
+	h := make(routing.Packet, routing.PacketHeaderSize)
 	if _, err = io.ReadFull(conn, h); err != nil {
 		return nil, err
 	}
@@ -325,8 +325,8 @@ func (mt *ManagedTransport) readPacket() (packet routing.Packet, err error) {
 		return nil, err
 	}
 	packet = append(h, p...)
-	if n := len(packet); n > 6 {
-		mt.logRecv(uint64(n - 6))
+	if n := len(packet); n > routing.PacketHeaderSize {
+		mt.logRecv(uint64(n - routing.PacketHeaderSize))
 	}
 	mt.log.Infof("recv packet: rtID(%d) size(%d)", packet.RouteID(), packet.Size())
 	return packet, nil