all: new p2p node representation (#17643)

Package p2p/enode provides a generalized representation of p2p nodes
which can contain arbitrary information in key/value pairs. It is also
the new home for the node database. The "v4" identity scheme is also
moved here from p2p/enr to remove the dependency on Ethereum crypto from
that package.

Record signature handling is changed significantly. The identity scheme
registry is removed and acceptable schemes must be passed to any method
that needs identity. This means records must now be validated explicitly
after decoding.

The enode API is designed to make signature handling easy and safe: most
APIs around the codebase work with enode.Node, which is a wrapper around
a valid record. Going from enr.Record to enode.Node requires a valid
signature.

* p2p/discover: port to p2p/enode

This ports the discovery code to the new node representation in
p2p/enode. The wire protocol is unchanged, this can be considered a
refactoring change. The Kademlia table can now deal with nodes using an
arbitrary identity scheme. This requires a few incompatible API changes:

  - Table.Lookup is not available anymore. It used to take a public key
    as argument because v4 protocol requires one. Its replacement is
    LookupRandom.
  - Table.Resolve takes *enode.Node instead of NodeID. This is also for
    v4 protocol compatibility because nodes cannot be looked up by ID
    alone.
  - Types Node and NodeID are gone. Further commits in the series will be
    fixes all over the the codebase to deal with those removals.

* p2p: port to p2p/enode and discovery changes

This adapts package p2p to the changes in p2p/discover. All uses of
discover.Node and discover.NodeID are replaced by their equivalents from
p2p/enode.

New API is added to retrieve the enode.Node instance of a peer. The
behavior of Server.Self with discovery disabled is improved. It now
tries much harder to report a working IP address, falling back to
127.0.0.1 if no suitable address can be determined through other means.
These changes were needed for tests of other packages later in the
series.

* p2p/simulations, p2p/testing: port to p2p/enode

No surprises here, mostly replacements of discover.Node, discover.NodeID
with their new equivalents. The 'interesting' API changes are:

 - testing.ProtocolSession tracks complete nodes, not just their IDs.
 - adapters.NodeConfig has a new method to create a complete node.

These changes were needed to make swarm tests work.

Note that the NodeID change makes the code incompatible with old
simulation snapshots.

* whisper/whisperv5, whisper/whisperv6: port to p2p/enode

This port was easy because whisper uses []byte for node IDs and
URL strings in the API.

* eth: port to p2p/enode

Again, easy to port because eth uses strings for node IDs and doesn't
care about node information in any way.

* les: port to p2p/enode

Apart from replacing discover.NodeID with enode.ID, most changes are in
the server pool code. It now deals with complete nodes instead
of (Pubkey, IP, Port) triples. The database format is unchanged for now,
but we should probably change it to use the node database later.

* node: port to p2p/enode

This change simply replaces discover.Node and discover.NodeID with their
new equivalents.

* swarm/network: port to p2p/enode

Swarm has its own node address representation, BzzAddr, containing both
an overlay address (the hash of a secp256k1 public key) and an underlay
address (enode:// URL).

There are no changes to the BzzAddr format in this commit, but certain
operations such as creating a BzzAddr from a node ID are now impossible
because node IDs aren't public keys anymore.

Most swarm-related changes in the series remove uses of
NewAddrFromNodeID, replacing it with NewAddr which takes a complete node
as argument. ToOverlayAddr is removed because we can just use the node
ID directly.

3 files changed, 29 insertions, 29 deletions

diff --git a/p2p/testing/peerpool.go b/p2p/testing/peerpool.go
index ed00396e2..01ccce67e 100644
--- a/p2p/testing/peerpool.go
+++ b/p2p/testing/peerpool.go
@@ -21,22 +21,22 @@ import (
 	"sync"
 
 	"github.com/ethereum/go-ethereum/log"
-	"github.com/ethereum/go-ethereum/p2p/discover"
+	"github.com/ethereum/go-ethereum/p2p/enode"
 )
 
 type TestPeer interface {
-	ID() discover.NodeID
+	ID() enode.ID
 	Drop(error)
 }
 
 // TestPeerPool is an example peerPool to demonstrate registration of peer connections
 type TestPeerPool struct {
 	lock  sync.Mutex
-	peers map[discover.NodeID]TestPeer
+	peers map[enode.ID]TestPeer
 }
 
 func NewTestPeerPool() *TestPeerPool {
-	return &TestPeerPool{peers: make(map[discover.NodeID]TestPeer)}
+	return &TestPeerPool{peers: make(map[enode.ID]TestPeer)}
 }
 
 func (p *TestPeerPool) Add(peer TestPeer) {
@@ -53,14 +53,14 @@ func (p *TestPeerPool) Remove(peer TestPeer) {
 	delete(p.peers, peer.ID())
 }
 
-func (p *TestPeerPool) Has(id discover.NodeID) bool {
+func (p *TestPeerPool) Has(id enode.ID) bool {
 	p.lock.Lock()
 	defer p.lock.Unlock()
 	_, ok := p.peers[id]
 	return ok
 }
 
-func (p *TestPeerPool) Get(id discover.NodeID) TestPeer {
+func (p *TestPeerPool) Get(id enode.ID) TestPeer {
 	p.lock.Lock()
 	defer p.lock.Unlock()
 	return p.peers[id]
diff --git a/p2p/testing/protocolsession.go b/p2p/testing/protocolsession.go
index e3ec41ad6..476c2a984 100644
--- a/p2p/testing/protocolsession.go
+++ b/p2p/testing/protocolsession.go
@@ -24,7 +24,7 @@ import (
 
 	"github.com/ethereum/go-ethereum/log"
 	"github.com/ethereum/go-ethereum/p2p"
-	"github.com/ethereum/go-ethereum/p2p/discover"
+	"github.com/ethereum/go-ethereum/p2p/enode"
 	"github.com/ethereum/go-ethereum/p2p/simulations/adapters"
 )
 
@@ -35,7 +35,7 @@ var errTimedOut = errors.New("timed out")
 // receive (expect) messages
 type ProtocolSession struct {
 	Server  *p2p.Server
-	IDs     []discover.NodeID
+	Nodes   []*enode.Node
 	adapter *adapters.SimAdapter
 	events  chan *p2p.PeerEvent
 }
@@ -56,32 +56,32 @@ type Exchange struct {
 // Trigger is part of the exchange, incoming message for the pivot node
 // sent by a peer
 type Trigger struct {
-	Msg     interface{}     // type of message to be sent
-	Code    uint64          // code of message is given
-	Peer    discover.NodeID // the peer to send the message to
-	Timeout time.Duration   // timeout duration for the sending
+	Msg     interface{}   // type of message to be sent
+	Code    uint64        // code of message is given
+	Peer    enode.ID      // the peer to send the message to
+	Timeout time.Duration // timeout duration for the sending
 }
 
 // Expect is part of an exchange, outgoing message from the pivot node
 // received by a peer
 type Expect struct {
-	Msg     interface{}     // type of message to expect
-	Code    uint64          // code of message is now given
-	Peer    discover.NodeID // the peer that expects the message
-	Timeout time.Duration   // timeout duration for receiving
+	Msg     interface{}   // type of message to expect
+	Code    uint64        // code of message is now given
+	Peer    enode.ID      // the peer that expects the message
+	Timeout time.Duration // timeout duration for receiving
 }
 
 // Disconnect represents a disconnect event, used and checked by TestDisconnected
 type Disconnect struct {
-	Peer  discover.NodeID // discconnected peer
-	Error error           // disconnect reason
+	Peer  enode.ID // discconnected peer
+	Error error    // disconnect reason
 }
 
 // trigger sends messages from peers
 func (s *ProtocolSession) trigger(trig Trigger) error {
 	simNode, ok := s.adapter.GetNode(trig.Peer)
 	if !ok {
-		return fmt.Errorf("trigger: peer %v does not exist (1- %v)", trig.Peer, len(s.IDs))
+		return fmt.Errorf("trigger: peer %v does not exist (1- %v)", trig.Peer, len(s.Nodes))
 	}
 	mockNode, ok := simNode.Services()[0].(*mockNode)
 	if !ok {
@@ -111,7 +111,7 @@ func (s *ProtocolSession) trigger(trig Trigger) error {
 // expect checks an expectation of a message sent out by the pivot node
 func (s *ProtocolSession) expect(exps []Expect) error {
 	// construct a map of expectations for each node
-	peerExpects := make(map[discover.NodeID][]Expect)
+	peerExpects := make(map[enode.ID][]Expect)
 	for _, exp := range exps {
 		if exp.Msg == nil {
 			return errors.New("no message to expect")
@@ -120,11 +120,11 @@ func (s *ProtocolSession) expect(exps []Expect) error {
 	}
 
 	// construct a map of mockNodes for each node
-	mockNodes := make(map[discover.NodeID]*mockNode)
+	mockNodes := make(map[enode.ID]*mockNode)
 	for nodeID := range peerExpects {
 		simNode, ok := s.adapter.GetNode(nodeID)
 		if !ok {
-			return fmt.Errorf("trigger: peer %v does not exist (1- %v)", nodeID, len(s.IDs))
+			return fmt.Errorf("trigger: peer %v does not exist (1- %v)", nodeID, len(s.Nodes))
 		}
 		mockNode, ok := simNode.Services()[0].(*mockNode)
 		if !ok {
@@ -253,7 +253,7 @@ func (s *ProtocolSession) testExchange(e Exchange) error {
 // TestDisconnected tests the disconnections given as arguments
 // the disconnect structs describe what disconnect error is expected on which peer
 func (s *ProtocolSession) TestDisconnected(disconnects ...*Disconnect) error {
-	expects := make(map[discover.NodeID]error)
+	expects := make(map[enode.ID]error)
 	for _, disconnect := range disconnects {
 		expects[disconnect.Peer] = disconnect.Error
 	}
diff --git a/p2p/testing/protocoltester.go b/p2p/testing/protocoltester.go
index c99578fe0..afc03b009 100644
--- a/p2p/testing/protocoltester.go
+++ b/p2p/testing/protocoltester.go
@@ -35,7 +35,7 @@ import (
 	"github.com/ethereum/go-ethereum/log"
 	"github.com/ethereum/go-ethereum/node"
 	"github.com/ethereum/go-ethereum/p2p"
-	"github.com/ethereum/go-ethereum/p2p/discover"
+	"github.com/ethereum/go-ethereum/p2p/enode"
 	"github.com/ethereum/go-ethereum/p2p/simulations"
 	"github.com/ethereum/go-ethereum/p2p/simulations/adapters"
 	"github.com/ethereum/go-ethereum/rlp"
@@ -52,7 +52,7 @@ type ProtocolTester struct {
 // NewProtocolTester constructs a new ProtocolTester
 // it takes as argument the pivot node id, the number of dummy peers and the
 // protocol run function called on a peer connection by the p2p server
-func NewProtocolTester(t *testing.T, id discover.NodeID, n int, run func(*p2p.Peer, p2p.MsgReadWriter) error) *ProtocolTester {
+func NewProtocolTester(t *testing.T, id enode.ID, n int, run func(*p2p.Peer, p2p.MsgReadWriter) error) *ProtocolTester {
 	services := adapters.Services{
 		"test": func(ctx *adapters.ServiceContext) (node.Service, error) {
 			return &testNode{run}, nil
@@ -76,17 +76,17 @@ func NewProtocolTester(t *testing.T, id discover.NodeID, n int, run func(*p2p.Pe
 
 	node := net.GetNode(id).Node.(*adapters.SimNode)
 	peers := make([]*adapters.NodeConfig, n)
-	peerIDs := make([]discover.NodeID, n)
+	nodes := make([]*enode.Node, n)
 	for i := 0; i < n; i++ {
 		peers[i] = adapters.RandomNodeConfig()
 		peers[i].Services = []string{"mock"}
-		peerIDs[i] = peers[i].ID
+		nodes[i] = peers[i].Node()
 	}
 	events := make(chan *p2p.PeerEvent, 1000)
 	node.SubscribeEvents(events)
 	ps := &ProtocolSession{
 		Server:  node.Server(),
-		IDs:     peerIDs,
+		Nodes:   nodes,
 		adapter: adapter,
 		events:  events,
 	}
@@ -108,7 +108,7 @@ func (t *ProtocolTester) Stop() error {
 
 // Connect brings up the remote peer node and connects it using the
 // p2p/simulations network connection with the in memory network adapter
-func (t *ProtocolTester) Connect(selfID discover.NodeID, peers ...*adapters.NodeConfig) {
+func (t *ProtocolTester) Connect(selfID enode.ID, peers ...*adapters.NodeConfig) {
 	for _, peer := range peers {
 		log.Trace(fmt.Sprintf("start node %v", peer.ID))
 		if _, err := t.network.NewNodeWithConfig(peer); err != nil {