dex: remove DAO related code

2 files changed, 2 insertions, 62 deletions

diff --git a/dex/handler.go b/dex/handler.go
index 5348b06f2..67cbe8a63 100644
--- a/dex/handler.go
+++ b/dex/handler.go
@@ -28,7 +28,6 @@ import (
 
 	"github.com/dexon-foundation/dexon/common"
 	"github.com/dexon-foundation/dexon/consensus"
-	"github.com/dexon-foundation/dexon/consensus/misc"
 	"github.com/dexon-foundation/dexon/core"
 	"github.com/dexon-foundation/dexon/core/types"
 	"github.com/dexon-foundation/dexon/eth/downloader"
@@ -53,10 +52,6 @@ const (
 	metaChanSize = 10240
 )
 
-var (
-	daoChallengeTimeout = 15 * time.Second // Time allowance for a node to reply to the DAO handshake challenge
-)
-
 // errIncompatibleConfig is returned if the requested protocols and configs are
 // not compatible (low protocol version restrictions and high requirements).
 var errIncompatibleConfig = errors.New("incompatible configuration")
@@ -316,25 +311,6 @@ func (pm *ProtocolManager) handle(p *peer) error {
 	pm.syncTransactions(p)
 	pm.syncNodeMetas(p)
 
-	// If we're DAO hard-fork aware, validate any remote peer with regard to the hard-fork
-	if daoBlock := pm.chainconfig.DAOForkBlock; daoBlock != nil {
-		// Request the peer's DAO fork header for extra-data validation
-		if err := p.RequestHeadersByNumber(daoBlock.Uint64(), 1, 0, false); err != nil {
-			return err
-		}
-		// Start a timer to disconnect if the peer doesn't reply in time
-		p.forkDrop = time.AfterFunc(daoChallengeTimeout, func() {
-			p.Log().Debug("Timed out DAO fork-check, dropping")
-			pm.removePeer(p.id)
-		})
-		// Make sure it's cleaned up if the peer dies off
-		defer func() {
-			if p.forkDrop != nil {
-				p.forkDrop.Stop()
-				p.forkDrop = nil
-			}
-		}()
-	}
 	// main loop. handle incoming messages.
 	for {
 		if err := pm.handleMsg(p); err != nil {
@@ -457,44 +433,9 @@ func (pm *ProtocolManager) handleMsg(p *peer) error {
 		if err := msg.Decode(&headers); err != nil {
 			return errResp(ErrDecode, "msg %v: %v", msg, err)
 		}
-		// If no headers were received, but we're expending a DAO fork check, maybe it's that
-		if len(headers) == 0 && p.forkDrop != nil {
-			// Possibly an empty reply to the fork header checks, sanity check TDs
-			verifyDAO := true
-
-			// If we already have a DAO header, we can check the peer's TD against it. If
-			// the peer's ahead of this, it too must have a reply to the DAO check
-			if daoHeader := pm.blockchain.GetHeaderByNumber(pm.chainconfig.DAOForkBlock.Uint64()); daoHeader != nil {
-				if _, td := p.Head(); td.Cmp(pm.blockchain.GetTd(daoHeader.Hash(), daoHeader.Number.Uint64())) >= 0 {
-					verifyDAO = false
-				}
-			}
-			// If we're seemingly on the same chain, disable the drop timer
-			if verifyDAO {
-				p.Log().Debug("Seems to be on the same side of the DAO fork")
-				p.forkDrop.Stop()
-				p.forkDrop = nil
-				return nil
-			}
-		}
 		// Filter out any explicitly requested headers, deliver the rest to the downloader
 		filter := len(headers) == 1
 		if filter {
-			// If it's a potential DAO fork check, validate against the rules
-			if p.forkDrop != nil && pm.chainconfig.DAOForkBlock.Cmp(headers[0].Number) == 0 {
-				// Disable the fork drop timer
-				p.forkDrop.Stop()
-				p.forkDrop = nil
-
-				// Validate the header and either drop the peer or continue
-				if err := misc.VerifyDAOHeaderExtraData(pm.chainconfig, headers[0]); err != nil {
-					p.Log().Debug("Verified to be on the other side of the DAO fork, dropping")
-					return err
-				}
-				p.Log().Debug("Verified to be on the same side of the DAO fork")
-				return nil
-			}
-			// Irrelevant of the fork checks, send the header to the fetcher just in case
 			headers = pm.fetcher.FilterHeaders(p.id, headers, time.Now())
 		}
 		if len(headers) > 0 || !filter {
diff --git a/dex/peer.go b/dex/peer.go
index 8c218f1d9..05947b456 100644
--- a/dex/peer.go
+++ b/dex/peer.go
@@ -97,9 +97,8 @@ type peer struct {
 	*p2p.Peer
 	rw p2p.MsgReadWriter
 
-	version  int // Protocol version negotiated
-	labels   mapset.Set
-	forkDrop *time.Timer // Timed connection dropper if forks aren't validated in time
+	version int // Protocol version negotiated
+	labels  mapset.Set
 
 	head common.Hash
 	td   *big.Int