swarm: Added lightnode flag (#17291)

* swarm: Added lightnode flag

Added --lightnode command line parameter
Added LightNode to Handshake message

* swarm/config: Fixed variable naming

* cmd/swarm: Changed BoolTFlag to BoolFlag for SwarmLightNodeEnabled

* swarm/network: Changed logging

* swarm/network: Changed protocol version testing

* swarm/network: Renamed DefaultNetworkID variable to TestProtocolNetworkID

* swarm/network: Bumped protocol version

* swarm/network: Changed LightNode handhsake test to table driven

* swarm/network: Changed back TestProtocolVersion to 5 for now

* swarm/network: Moved the test configuration inside the test function scope

6 files changed, 95 insertions, 17 deletions

diff --git a/cmd/swarm/config.go b/cmd/swarm/config.go
index ce2acdcc9..ff085fd94 100644
--- a/cmd/swarm/config.go
+++ b/cmd/swarm/config.go
@@ -68,6 +68,7 @@ const (
 	SWARM_ENV_SWAP_API             = "SWARM_SWAP_API"
 	SWARM_ENV_SYNC_DISABLE         = "SWARM_SYNC_DISABLE"
 	SWARM_ENV_SYNC_UPDATE_DELAY    = "SWARM_ENV_SYNC_UPDATE_DELAY"
+	SWARM_ENV_LIGHT_NODE_ENABLE    = "SWARM_LIGHT_NODE_ENABLE"
 	SWARM_ENV_DELIVERY_SKIP_CHECK  = "SWARM_DELIVERY_SKIP_CHECK"
 	SWARM_ENV_ENS_API              = "SWARM_ENS_API"
 	SWARM_ENV_ENS_ADDR             = "SWARM_ENS_ADDR"
@@ -204,6 +205,10 @@ func cmdLineOverride(currentConfig *bzzapi.Config, ctx *cli.Context) *bzzapi.Con
 		currentConfig.SyncUpdateDelay = d
 	}
 
+	if ctx.GlobalIsSet(SwarmLightNodeEnabled.Name) {
+		currentConfig.LightNodeEnabled = true
+	}
+
 	if ctx.GlobalIsSet(SwarmDeliverySkipCheckFlag.Name) {
 		currentConfig.DeliverySkipCheck = true
 	}
@@ -301,6 +306,12 @@ func envVarsOverride(currentConfig *bzzapi.Config) (config *bzzapi.Config) {
 		}
 	}
 
+	if lne := os.Getenv(SWARM_ENV_LIGHT_NODE_ENABLE); lne != "" {
+		if lightnode, err := strconv.ParseBool(lne); err != nil {
+			currentConfig.LightNodeEnabled = lightnode
+		}
+	}
+
 	if swapapi := os.Getenv(SWARM_ENV_SWAP_API); swapapi != "" {
 		currentConfig.SwapAPI = swapapi
 	}
diff --git a/cmd/swarm/main.go b/cmd/swarm/main.go
index 9185af980..258f24d32 100644
--- a/cmd/swarm/main.go
+++ b/cmd/swarm/main.go
@@ -123,6 +123,11 @@ var (
 		Usage:  "Duration for sync subscriptions update after no new peers are added (default 15s)",
 		EnvVar: SWARM_ENV_SYNC_UPDATE_DELAY,
 	}
+	SwarmLightNodeEnabled = cli.BoolFlag{
+		Name:   "lightnode",
+		Usage:  "Enable Swarm LightNode (default false)",
+		EnvVar: SWARM_ENV_LIGHT_NODE_ENABLE,
+	}
 	SwarmDeliverySkipCheckFlag = cli.BoolFlag{
 		Name:   "delivery-skip-check",
 		Usage:  "Skip chunk delivery check (default false)",
@@ -464,6 +469,7 @@ pv(1) tool to get a progress bar:
 		SwarmSwapAPIFlag,
 		SwarmSyncDisabledFlag,
 		SwarmSyncUpdateDelay,
+		SwarmLightNodeEnabled,
 		SwarmDeliverySkipCheckFlag,
 		SwarmListenAddrFlag,
 		SwarmPortFlag,
diff --git a/swarm/api/config.go b/swarm/api/config.go
index 939285e09..bdfffdd05 100644
--- a/swarm/api/config.go
+++ b/swarm/api/config.go
@@ -63,6 +63,7 @@ type Config struct {
 	SwapEnabled       bool
 	SyncEnabled       bool
 	DeliverySkipCheck bool
+	LightNodeEnabled  bool
 	SyncUpdateDelay   time.Duration
 	SwapAPI           string
 	Cors              string
diff --git a/swarm/network/protocol.go b/swarm/network/protocol.go
index 49ae5a15b..7e7fee8ef 100644
--- a/swarm/network/protocol.go
+++ b/swarm/network/protocol.go
@@ -94,12 +94,14 @@ type BzzConfig struct {
 	UnderlayAddr []byte // node's underlay address
 	HiveParams   *HiveParams
 	NetworkID    uint64
+	LightNode    bool
 }
 
 // Bzz is the swarm protocol bundle
 type Bzz struct {
 	*Hive
 	NetworkID    uint64
+	LightNode    bool
 	localAddr    *BzzAddr
 	mtx          sync.Mutex
 	handshakes   map[discover.NodeID]*HandshakeMsg
@@ -116,6 +118,7 @@ func NewBzz(config *BzzConfig, kad Overlay, store state.Store, streamerSpec *pro
 	return &Bzz{
 		Hive:         NewHive(config.HiveParams, kad, store),
 		NetworkID:    config.NetworkID,
+		LightNode:    config.LightNode,
 		localAddr:    &BzzAddr{config.OverlayAddr, config.UnderlayAddr},
 		handshakes:   make(map[discover.NodeID]*HandshakeMsg),
 		streamerRun:  streamerRun,
@@ -209,7 +212,11 @@ func (b *Bzz) RunProtocol(spec *protocols.Spec, run func(*BzzPeer) error) func(*
 			localAddr:  b.localAddr,
 			BzzAddr:    handshake.peerAddr,
 			lastActive: time.Now(),
+			LightNode:  handshake.LightNode,
 		}
+
+		log.Debug("peer created", "addr", handshake.peerAddr.String())
+
 		return run(peer)
 	}
 }
@@ -228,6 +235,7 @@ func (b *Bzz) performHandshake(p *protocols.Peer, handshake *HandshakeMsg) error
 		return err
 	}
 	handshake.peerAddr = rsh.(*HandshakeMsg).Addr
+	handshake.LightNode = rsh.(*HandshakeMsg).LightNode
 	return nil
 }
 
@@ -263,6 +271,7 @@ type BzzPeer struct {
 	localAddr       *BzzAddr  // local Peers address
 	*BzzAddr                  // remote address -> implements Addr interface = protocols.Peer
 	lastActive      time.Time // time is updated whenever mutexes are releasing
+	LightNode       bool
 }
 
 func NewBzzTestPeer(p *protocols.Peer, addr *BzzAddr) *BzzPeer {
@@ -294,6 +303,7 @@ type HandshakeMsg struct {
 	Version   uint64
 	NetworkID uint64
 	Addr      *BzzAddr
+	LightNode bool
 
 	// peerAddr is the address received in the peer handshake
 	peerAddr *BzzAddr
@@ -305,7 +315,7 @@ type HandshakeMsg struct {
 
 // String pretty prints the handshake
 func (bh *HandshakeMsg) String() string {
-	return fmt.Sprintf("Handshake: Version: %v, NetworkID: %v, Addr: %v", bh.Version, bh.NetworkID, bh.Addr)
+	return fmt.Sprintf("Handshake: Version: %v, NetworkID: %v, Addr: %v, LightNode: %v, peerAddr: %v", bh.Version, bh.NetworkID, bh.Addr, bh.LightNode, bh.peerAddr)
 }
 
 // Perform initiates the handshake and validates the remote handshake message
@@ -338,6 +348,7 @@ func (b *Bzz) GetHandshake(peerID discover.NodeID) (*HandshakeMsg, bool) {
 			Version:   uint64(BzzSpec.Version),
 			NetworkID: b.NetworkID,
 			Addr:      b.localAddr,
+			LightNode: b.LightNode,
 			init:      make(chan bool, 1),
 			done:      make(chan struct{}),
 		}
diff --git a/swarm/network/protocol_test.go b/swarm/network/protocol_test.go
index 63faf3108..b74b72c68 100644
--- a/swarm/network/protocol_test.go
+++ b/swarm/network/protocol_test.go
@@ -30,6 +30,11 @@ import (
 	p2ptest "github.com/ethereum/go-ethereum/p2p/testing"
 )
 
+const (
+	TestProtocolVersion   = 5
+	TestProtocolNetworkID = 3
+)
+
 var (
 	loglevel = flag.Int("loglevel", 2, "verbosity of logs")
 )
@@ -127,23 +132,30 @@ type bzzTester struct {
 	*p2ptest.ProtocolTester
 	addr *BzzAddr
 	cs   map[string]chan bool
+	bzz  *Bzz
 }
 
-func newBzzHandshakeTester(t *testing.T, n int, addr *BzzAddr) *bzzTester {
+func newBzz(addr *BzzAddr, lightNode bool) *Bzz {
 	config := &BzzConfig{
 		OverlayAddr:  addr.Over(),
 		UnderlayAddr: addr.Under(),
 		HiveParams:   NewHiveParams(),
 		NetworkID:    DefaultNetworkID,
+		LightNode:    lightNode,
 	}
 	kad := NewKademlia(addr.OAddr, NewKadParams())
 	bzz := NewBzz(config, kad, nil, nil, nil)
+	return bzz
+}
 
-	s := p2ptest.NewProtocolTester(t, NewNodeIDFromAddr(addr), 1, bzz.runBzz)
+func newBzzHandshakeTester(t *testing.T, n int, addr *BzzAddr, lightNode bool) *bzzTester {
+	bzz := newBzz(addr, lightNode)
+	pt := p2ptest.NewProtocolTester(t, NewNodeIDFromAddr(addr), n, bzz.runBzz)
 
 	return &bzzTester{
 		addr:           addr,
-		ProtocolTester: s,
+		ProtocolTester: pt,
+		bzz:            bzz,
 	}
 }
 
@@ -184,22 +196,24 @@ func (s *bzzTester) testHandshake(lhs, rhs *HandshakeMsg, disconnects ...*p2ptes
 	return nil
 }
 
-func correctBzzHandshake(addr *BzzAddr) *HandshakeMsg {
+func correctBzzHandshake(addr *BzzAddr, lightNode bool) *HandshakeMsg {
 	return &HandshakeMsg{
-		Version:   5,
-		NetworkID: DefaultNetworkID,
+		Version:   TestProtocolVersion,
+		NetworkID: TestProtocolNetworkID,
 		Addr:      addr,
+		LightNode: lightNode,
 	}
 }
 
 func TestBzzHandshakeNetworkIDMismatch(t *testing.T) {
+	lightNode := false
 	addr := RandomAddr()
-	s := newBzzHandshakeTester(t, 1, addr)
+	s := newBzzHandshakeTester(t, 1, addr, lightNode)
 	id := s.IDs[0]
 
 	err := s.testHandshake(
-		correctBzzHandshake(addr),
-		&HandshakeMsg{Version: 5, NetworkID: 321, Addr: NewAddrFromNodeID(id)},
+		correctBzzHandshake(addr, lightNode),
+		&HandshakeMsg{Version: TestProtocolVersion, NetworkID: 321, Addr: NewAddrFromNodeID(id)},
 		&p2ptest.Disconnect{Peer: id, Error: fmt.Errorf("Handshake error: Message handler error: (msg code 0): network id mismatch 321 (!= 3)")},
 	)
 
@@ -209,14 +223,15 @@ func TestBzzHandshakeNetworkIDMismatch(t *testing.T) {
 }
 
 func TestBzzHandshakeVersionMismatch(t *testing.T) {
+	lightNode := false
 	addr := RandomAddr()
-	s := newBzzHandshakeTester(t, 1, addr)
+	s := newBzzHandshakeTester(t, 1, addr, lightNode)
 	id := s.IDs[0]
 
 	err := s.testHandshake(
-		correctBzzHandshake(addr),
-		&HandshakeMsg{Version: 0, NetworkID: 3, Addr: NewAddrFromNodeID(id)},
-		&p2ptest.Disconnect{Peer: id, Error: fmt.Errorf("Handshake error: Message handler error: (msg code 0): version mismatch 0 (!= 5)")},
+		correctBzzHandshake(addr, lightNode),
+		&HandshakeMsg{Version: 0, NetworkID: TestProtocolNetworkID, Addr: NewAddrFromNodeID(id)},
+		&p2ptest.Disconnect{Peer: id, Error: fmt.Errorf("Handshake error: Message handler error: (msg code 0): version mismatch 0 (!= %d)", TestProtocolVersion)},
 	)
 
 	if err != nil {
@@ -225,16 +240,49 @@ func TestBzzHandshakeVersionMismatch(t *testing.T) {
 }
 
 func TestBzzHandshakeSuccess(t *testing.T) {
+	lightNode := false
 	addr := RandomAddr()
-	s := newBzzHandshakeTester(t, 1, addr)
+	s := newBzzHandshakeTester(t, 1, addr, lightNode)
 	id := s.IDs[0]
 
 	err := s.testHandshake(
-		correctBzzHandshake(addr),
-		&HandshakeMsg{Version: 5, NetworkID: 3, Addr: NewAddrFromNodeID(id)},
+		correctBzzHandshake(addr, lightNode),
+		&HandshakeMsg{Version: TestProtocolVersion, NetworkID: TestProtocolNetworkID, Addr: NewAddrFromNodeID(id)},
 	)
 
 	if err != nil {
 		t.Fatal(err)
 	}
 }
+
+func TestBzzHandshakeLightNode(t *testing.T) {
+	var lightNodeTests = []struct {
+		name      string
+		lightNode bool
+	}{
+		{"on", true},
+		{"off", false},
+	}
+
+	for _, test := range lightNodeTests {
+		t.Run(test.name, func(t *testing.T) {
+			randomAddr := RandomAddr()
+			pt := newBzzHandshakeTester(t, 1, randomAddr, false)
+			id := pt.IDs[0]
+			addr := NewAddrFromNodeID(id)
+
+			err := pt.testHandshake(
+				correctBzzHandshake(randomAddr, false),
+				&HandshakeMsg{Version: TestProtocolVersion, NetworkID: TestProtocolNetworkID, Addr: addr, LightNode: test.lightNode},
+			)
+
+			if err != nil {
+				t.Fatal(err)
+			}
+
+			if pt.bzz.handshakes[id].LightNode != test.lightNode {
+				t.Fatalf("peer LightNode flag is %v, should be %v", pt.bzz.handshakes[id].LightNode, test.lightNode)
+			}
+		})
+	}
+}
diff --git a/swarm/swarm.go b/swarm/swarm.go
index db7d2dfed..c380a376f 100644
--- a/swarm/swarm.go
+++ b/swarm/swarm.go
@@ -143,6 +143,7 @@ func NewSwarm(config *api.Config, mockStore *mock.NodeStore) (self *Swarm, err e
 		OverlayAddr:  addr.OAddr,
 		UnderlayAddr: addr.UAddr,
 		HiveParams:   config.HiveParams,
+		LightNode:    config.LightNodeEnabled,
 	}
 
 	stateStore, err := state.NewDBStore(filepath.Join(config.Path, "state-store.db"))