Merge pull request #1247 from davecgh/peer_minor_cleanup

peer: Minor function definition order cleanup.

peer/peer.go

@@ -1,4 +1,5 @@
-// Copyright (c) 2013-2016 The btcsuite developers
+// Copyright (c) 2013-2018 The btcsuite developers
+// Copyright (c) 2016-2018 The Decred developers
 // Use of this source code is governed by an ISC
 // license that can be found in the LICENSE file.
 
@@ -801,85 +802,6 @@ func (p *Peer) IsWitnessEnabled() bool {
 	return witnessEnabled
 }
 
-// localVersionMsg creates a version message that can be used to send to the
-// remote peer.
-func (p *Peer) localVersionMsg() (*wire.MsgVersion, error) {
-	var blockNum int32
-	if p.cfg.NewestBlock != nil {
-		var err error
-		_, blockNum, err = p.cfg.NewestBlock()
-		if err != nil {
-			return nil, err
-		}
-	}
-
-	theirNA := p.na
-
-	// If we are behind a proxy and the connection comes from the proxy then
-	// we return an unroutable address as their address. This is to prevent
-	// leaking the tor proxy address.
-	if p.cfg.Proxy != "" {
-		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.NewNetAddressIPPort(net.IP([]byte{0, 0, 0, 0}), 0, 0)
-		}
-	}
-
-	// Create a wire.NetAddress with only the services set to use as the
-	// "addrme" in the version message.
-	//
-	// Older nodes previously added the IP and port information to the
-	// address manager which proved to be unreliable as an inbound
-	// connection from a peer didn't necessarily mean the peer itself
-	// accepted inbound connections.
-	//
-	// Also, the timestamp is unused in the version message.
-	ourNA := &wire.NetAddress{
-		Services: p.cfg.Services,
-	}
-
-	// Generate a unique nonce for this peer so self connections can be
-	// detected.  This is accomplished by adding it to a size-limited map of
-	// recently seen nonces.
-	nonce := uint64(rand.Int63())
-	sentNonces.Add(nonce)
-
-	// Version message.
-	msg := wire.NewMsgVersion(ourNA, theirNA, nonce, blockNum)
-	msg.AddUserAgent(p.cfg.UserAgentName, p.cfg.UserAgentVersion,
-		p.cfg.UserAgentComments...)
-
-	// XXX: bitcoind appears to always enable the full node services flag
-	// of the remote peer netaddress field in the version message regardless
-	// of whether it knows it supports it or not.  Also, bitcoind sets
-	// the services field of the local peer to 0 regardless of support.
-	//
-	// Realistically, this should be set as follows:
-	// - For outgoing connections:
-	//    - Set the local netaddress services to what the local peer
-	//      actually supports
-	//    - Set the remote netaddress services to 0 to indicate no services
-	//      as they are still unknown
-	// - For incoming connections:
-	//    - Set the local netaddress services to what the local peer
-	//      actually supports
-	//    - Set the remote netaddress services to the what was advertised by
-	//      by the remote peer in its version message
-	msg.AddrYou.Services = wire.SFNodeNetwork
-
-	// Advertise the services flag
-	msg.Services = p.cfg.Services
-
-	// Advertise our max supported protocol version.
-	msg.ProtocolVersion = int32(p.cfg.ProtocolVersion)
-
-	// Advertise if inv messages for transactions are desired.
-	msg.DisableRelayTx = p.cfg.DisableRelayTx
-
-	return msg, nil
-}
-
 // PushAddrMsg sends an addr message to the connected peer using the provided
 // addresses.  This function is useful over manually sending the message via
 // QueueMessage since it automatically limits the addresses to the maximum
@@ -1041,72 +963,6 @@ func (p *Peer) PushRejectMsg(command string, code wire.RejectCode, reason string
 	<-doneChan
 }
 
-// handleRemoteVersionMsg is invoked when a version bitcoin message is received
-// from the remote peer.  It will return an error if the remote peer's version
-// is not compatible with ours.
-func (p *Peer) handleRemoteVersionMsg(msg *wire.MsgVersion) error {
-	// Detect self connections.
-	if !allowSelfConns && sentNonces.Exists(msg.Nonce) {
-		return errors.New("disconnecting peer connected to self")
-	}
-
-	// Notify and disconnect clients that have a protocol version that is
-	// too old.
-	//
-	// NOTE: If minAcceptableProtocolVersion is raised to be higher than
-	// wire.RejectVersion, this should send a reject packet before
-	// disconnecting.
-	if uint32(msg.ProtocolVersion) < minAcceptableProtocolVersion {
-		reason := fmt.Sprintf("protocol version must be %d or greater",
-			minAcceptableProtocolVersion)
-		return errors.New(reason)
-	}
-
-	// Updating a bunch of stats including block based stats, and the
-	// peer's time offset.
-	p.statsMtx.Lock()
-	p.lastBlock = msg.LastBlock
-	p.startingHeight = msg.LastBlock
-	p.timeOffset = msg.Timestamp.Unix() - time.Now().Unix()
-	p.statsMtx.Unlock()
-
-	// Negotiate the protocol version.
-	p.flagsMtx.Lock()
-	p.advertisedProtoVer = uint32(msg.ProtocolVersion)
-	p.protocolVersion = minUint32(p.protocolVersion, p.advertisedProtoVer)
-	p.versionKnown = true
-	log.Debugf("Negotiated protocol version %d for peer %s",
-		p.protocolVersion, p)
-
-	// Set the peer's ID.
-	p.id = atomic.AddInt32(&nodeCount, 1)
-
-	// Set the supported services for the peer to what the remote peer
-	// advertised.
-	p.services = msg.Services
-
-	// Set the remote peer's user agent.
-	p.userAgent = msg.UserAgent
-
-	// Determine if the peer would like to receive witness data with
-	// transactions, or not.
-	if p.services&wire.SFNodeWitness == wire.SFNodeWitness {
-		p.witnessEnabled = true
-	}
-	p.flagsMtx.Unlock()
-
-	// Once the version message has been exchanged, we're able to determine
-	// if this peer knows how to encode witness data over the wire
-	// protocol. If so, then we'll switch to a decoding mode which is
-	// prepared for the new transaction format introduced as part of
-	// BIP0144.
-	if p.services&wire.SFNodeWitness == wire.SFNodeWitness {
-		p.wireEncoding = wire.WitnessEncoding
-	}
-
-	return nil
-}
-
 // handlePingMsg is invoked when a peer receives a ping bitcoin message.  For
 // recent clients (protocol version > BIP0031Version), it replies with a pong
 // message.  For older clients, it does nothing and anything other than failure
@@ -1992,40 +1848,6 @@ func (p *Peer) QueueInventory(invVect *wire.InvVect) {
 	p.outputInvChan <- invVect
 }
 
-// AssociateConnection associates the given conn to the peer.   Calling this
-// function when the peer is already connected will have no effect.
-func (p *Peer) AssociateConnection(conn net.Conn) {
-	// Already connected?
-	if !atomic.CompareAndSwapInt32(&p.connected, 0, 1) {
-		return
-	}
-
-	p.conn = conn
-	p.timeConnected = time.Now()
-
-	if p.inbound {
-		p.addr = p.conn.RemoteAddr().String()
-
-		// Set up a NetAddress for the peer to be used with AddrManager.  We
-		// only do this inbound because outbound set this up at connection time
-		// and no point recomputing.
-		na, err := newNetAddress(p.conn.RemoteAddr(), p.services)
-		if err != nil {
-			log.Errorf("Cannot create remote net address: %v", err)
-			p.Disconnect()
-			return
-		}
-		p.na = na
-	}
-
-	go func() {
-		if err := p.start(); err != nil {
-			log.Debugf("Cannot start peer %v: %v", p, err)
-			p.Disconnect()
-		}
-	}()
-}
-
 // Connected returns whether or not the peer is currently connected.
 //
 // This function is safe for concurrent access.
@@ -2049,6 +1871,213 @@ func (p *Peer) Disconnect() {
 	close(p.quit)
 }
 
+// handleRemoteVersionMsg is invoked when a version bitcoin message is received
+// from the remote peer.  It will return an error if the remote peer's version
+// is not compatible with ours.
+func (p *Peer) handleRemoteVersionMsg(msg *wire.MsgVersion) error {
+	// Detect self connections.
+	if !allowSelfConns && sentNonces.Exists(msg.Nonce) {
+		return errors.New("disconnecting peer connected to self")
+	}
+
+	// Notify and disconnect clients that have a protocol version that is
+	// too old.
+	//
+	// NOTE: If minAcceptableProtocolVersion is raised to be higher than
+	// wire.RejectVersion, this should send a reject packet before
+	// disconnecting.
+	if uint32(msg.ProtocolVersion) < minAcceptableProtocolVersion {
+		reason := fmt.Sprintf("protocol version must be %d or greater",
+			minAcceptableProtocolVersion)
+		return errors.New(reason)
+	}
+
+	// Updating a bunch of stats including block based stats, and the
+	// peer's time offset.
+	p.statsMtx.Lock()
+	p.lastBlock = msg.LastBlock
+	p.startingHeight = msg.LastBlock
+	p.timeOffset = msg.Timestamp.Unix() - time.Now().Unix()
+	p.statsMtx.Unlock()
+
+	// Negotiate the protocol version.
+	p.flagsMtx.Lock()
+	p.advertisedProtoVer = uint32(msg.ProtocolVersion)
+	p.protocolVersion = minUint32(p.protocolVersion, p.advertisedProtoVer)
+	p.versionKnown = true
+	log.Debugf("Negotiated protocol version %d for peer %s",
+		p.protocolVersion, p)
+
+	// Set the peer's ID.
+	p.id = atomic.AddInt32(&nodeCount, 1)
+
+	// Set the supported services for the peer to what the remote peer
+	// advertised.
+	p.services = msg.Services
+
+	// Set the remote peer's user agent.
+	p.userAgent = msg.UserAgent
+
+	// Determine if the peer would like to receive witness data with
+	// transactions, or not.
+	if p.services&wire.SFNodeWitness == wire.SFNodeWitness {
+		p.witnessEnabled = true
+	}
+	p.flagsMtx.Unlock()
+
+	// Once the version message has been exchanged, we're able to determine
+	// if this peer knows how to encode witness data over the wire
+	// protocol. If so, then we'll switch to a decoding mode which is
+	// prepared for the new transaction format introduced as part of
+	// BIP0144.
+	if p.services&wire.SFNodeWitness == wire.SFNodeWitness {
+		p.wireEncoding = wire.WitnessEncoding
+	}
+
+	return nil
+}
+
+// readRemoteVersionMsg waits for the next message to arrive from the remote
+// peer.  If the next message is not a version message or the version is not
+// acceptable then return an error.
+func (p *Peer) readRemoteVersionMsg() error {
+	// Read their version message.
+	msg, _, err := p.readMessage(wire.LatestEncoding)
+	if err != nil {
+		return err
+	}
+
+	remoteVerMsg, ok := msg.(*wire.MsgVersion)
+	if !ok {
+		errStr := "A version message must precede all others"
+		log.Errorf(errStr)
+
+		rejectMsg := wire.NewMsgReject(msg.Command(), wire.RejectMalformed,
+			errStr)
+		return p.writeMessage(rejectMsg, wire.LatestEncoding)
+	}
+
+	if err := p.handleRemoteVersionMsg(remoteVerMsg); err != nil {
+		return err
+	}
+
+	if p.cfg.Listeners.OnVersion != nil {
+		p.cfg.Listeners.OnVersion(p, remoteVerMsg)
+	}
+	return nil
+}
+
+// localVersionMsg creates a version message that can be used to send to the
+// remote peer.
+func (p *Peer) localVersionMsg() (*wire.MsgVersion, error) {
+	var blockNum int32
+	if p.cfg.NewestBlock != nil {
+		var err error
+		_, blockNum, err = p.cfg.NewestBlock()
+		if err != nil {
+			return nil, err
+		}
+	}
+
+	theirNA := p.na
+
+	// If we are behind a proxy and the connection comes from the proxy then
+	// we return an unroutable address as their address. This is to prevent
+	// leaking the tor proxy address.
+	if p.cfg.Proxy != "" {
+		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.NewNetAddressIPPort(net.IP([]byte{0, 0, 0, 0}), 0, 0)
+		}
+	}
+
+	// Create a wire.NetAddress with only the services set to use as the
+	// "addrme" in the version message.
+	//
+	// Older nodes previously added the IP and port information to the
+	// address manager which proved to be unreliable as an inbound
+	// connection from a peer didn't necessarily mean the peer itself
+	// accepted inbound connections.
+	//
+	// Also, the timestamp is unused in the version message.
+	ourNA := &wire.NetAddress{
+		Services: p.cfg.Services,
+	}
+
+	// Generate a unique nonce for this peer so self connections can be
+	// detected.  This is accomplished by adding it to a size-limited map of
+	// recently seen nonces.
+	nonce := uint64(rand.Int63())
+	sentNonces.Add(nonce)
+
+	// Version message.
+	msg := wire.NewMsgVersion(ourNA, theirNA, nonce, blockNum)
+	msg.AddUserAgent(p.cfg.UserAgentName, p.cfg.UserAgentVersion,
+		p.cfg.UserAgentComments...)
+
+	// XXX: bitcoind appears to always enable the full node services flag
+	// of the remote peer netaddress field in the version message regardless
+	// of whether it knows it supports it or not.  Also, bitcoind sets
+	// the services field of the local peer to 0 regardless of support.
+	//
+	// Realistically, this should be set as follows:
+	// - For outgoing connections:
+	//    - Set the local netaddress services to what the local peer
+	//      actually supports
+	//    - Set the remote netaddress services to 0 to indicate no services
+	//      as they are still unknown
+	// - For incoming connections:
+	//    - Set the local netaddress services to what the local peer
+	//      actually supports
+	//    - Set the remote netaddress services to the what was advertised by
+	//      by the remote peer in its version message
+	msg.AddrYou.Services = wire.SFNodeNetwork
+
+	// Advertise the services flag
+	msg.Services = p.cfg.Services
+
+	// Advertise our max supported protocol version.
+	msg.ProtocolVersion = int32(p.cfg.ProtocolVersion)
+
+	// Advertise if inv messages for transactions are desired.
+	msg.DisableRelayTx = p.cfg.DisableRelayTx
+
+	return msg, nil
+}
+
+// writeLocalVersionMsg writes our version message to the remote peer.
+func (p *Peer) writeLocalVersionMsg() error {
+	localVerMsg, err := p.localVersionMsg()
+	if err != nil {
+		return err
+	}
+
+	return p.writeMessage(localVerMsg, wire.LatestEncoding)
+}
+
+// negotiateInboundProtocol waits to receive a version message from the peer
+// then sends our version message. If the events do not occur in that order then
+// it returns an error.
+func (p *Peer) negotiateInboundProtocol() error {
+	if err := p.readRemoteVersionMsg(); err != nil {
+		return err
+	}
+
+	return p.writeLocalVersionMsg()
+}
+
+// negotiateOutboundProtocol sends our version message then waits to receive a
+// version message from the peer.  If the events do not occur in that order then
+// it returns an error.
+func (p *Peer) negotiateOutboundProtocol() error {
+	if err := p.writeLocalVersionMsg(); err != nil {
+		return err
+	}
+
+	return p.readRemoteVersionMsg()
+}
+
 // start begins processing input and output messages.
 func (p *Peer) start() error {
 	log.Tracef("Starting peer %s", p)
@@ -2086,6 +2115,40 @@ func (p *Peer) start() error {
 	return nil
 }
 
+// AssociateConnection associates the given conn to the peer.   Calling this
+// function when the peer is already connected will have no effect.
+func (p *Peer) AssociateConnection(conn net.Conn) {
+	// Already connected?
+	if !atomic.CompareAndSwapInt32(&p.connected, 0, 1) {
+		return
+	}
+
+	p.conn = conn
+	p.timeConnected = time.Now()
+
+	if p.inbound {
+		p.addr = p.conn.RemoteAddr().String()
+
+		// Set up a NetAddress for the peer to be used with AddrManager.  We
+		// only do this inbound because outbound set this up at connection time
+		// and no point recomputing.
+		na, err := newNetAddress(p.conn.RemoteAddr(), p.services)
+		if err != nil {
+			log.Errorf("Cannot create remote net address: %v", err)
+			p.Disconnect()
+			return
+		}
+		p.na = na
+	}
+
+	go func() {
+		if err := p.start(); err != nil {
+			log.Debugf("Cannot start peer %v: %v", p, err)
+			p.Disconnect()
+		}
+	}()
+}
+
 // WaitForDisconnect waits until the peer has completely disconnected and all
 // resources are cleaned up.  This will happen if either the local or remote
 // side has been disconnected or the peer is forcibly disconnected via
@@ -2094,68 +2157,6 @@ func (p *Peer) WaitForDisconnect() {
 	<-p.quit
 }
 
-// readRemoteVersionMsg waits for the next message to arrive from the remote
-// peer.  If the next message is not a version message or the version is not
-// acceptable then return an error.
-func (p *Peer) readRemoteVersionMsg() error {
-	// Read their version message.
-	msg, _, err := p.readMessage(wire.LatestEncoding)
-	if err != nil {
-		return err
-	}
-
-	remoteVerMsg, ok := msg.(*wire.MsgVersion)
-	if !ok {
-		errStr := "A version message must precede all others"
-		log.Errorf(errStr)
-
-		rejectMsg := wire.NewMsgReject(msg.Command(), wire.RejectMalformed,
-			errStr)
-		return p.writeMessage(rejectMsg, wire.LatestEncoding)
-	}
-
-	if err := p.handleRemoteVersionMsg(remoteVerMsg); err != nil {
-		return err
-	}
-
-	if p.cfg.Listeners.OnVersion != nil {
-		p.cfg.Listeners.OnVersion(p, remoteVerMsg)
-	}
-	return nil
-}
-
-// writeLocalVersionMsg writes our version message to the remote peer.
-func (p *Peer) writeLocalVersionMsg() error {
-	localVerMsg, err := p.localVersionMsg()
-	if err != nil {
-		return err
-	}
-
-	return p.writeMessage(localVerMsg, wire.LatestEncoding)
-}
-
-// negotiateInboundProtocol waits to receive a version message from the peer
-// then sends our version message. If the events do not occur in that order then
-// it returns an error.
-func (p *Peer) negotiateInboundProtocol() error {
-	if err := p.readRemoteVersionMsg(); err != nil {
-		return err
-	}
-
-	return p.writeLocalVersionMsg()
-}
-
-// negotiateOutboundProtocol sends our version message then waits to receive a
-// version message from the peer.  If the events do not occur in that order then
-// it returns an error.
-func (p *Peer) negotiateOutboundProtocol() error {
-	if err := p.writeLocalVersionMsg(); err != nil {
-		return err
-	}
-
-	return p.readRemoteVersionMsg()
-}
-
 // newPeerBase returns a new base bitcoin peer based on the inbound flag.  This
 // is used by the NewInboundPeer and NewOutboundPeer functions to perform base
 // setup needed by both types of peers.