diff --git a/ethereum.go b/ethereum.go index 97ea35d453..0f5bd11a20 100644 --- a/ethereum.go +++ b/ethereum.go @@ -2,6 +2,7 @@ package eth import ( "container/list" + "fmt" "github.com/ethereum/eth-go/ethchain" "github.com/ethereum/eth-go/ethdb" "github.com/ethereum/eth-go/ethrpc" @@ -9,9 +10,11 @@ import ( "github.com/ethereum/eth-go/ethwire" "io/ioutil" "log" + "math/rand" "net" "net/http" "strconv" + "strings" "sync" "sync/atomic" "time" @@ -146,15 +149,51 @@ func (s *Ethereum) ConnectToPeer(addr string) error { if s.peers.Len() < s.MaxPeers { var alreadyConnected bool + ahost, _, _ := net.SplitHostPort(addr) + var chost string + + ips, err := net.LookupIP(ahost) + + if err != nil { + return err + } else { + // If more then one ip is available try stripping away the ipv6 ones + if len(ips) > 1 { + var ipsv4 []net.IP + // For now remove the ipv6 addresses + for _, ip := range ips { + if strings.Contains(ip.String(), "::") { + continue + } else { + ipsv4 = append(ipsv4, ip) + } + } + if len(ipsv4) == 0 { + return fmt.Errorf("[SERV] No IPV4 addresses available for hostname") + } + + // Pick a random ipv4 address, simulating round-robin DNS. + rand.Seed(time.Now().UTC().UnixNano()) + i := rand.Intn(len(ipsv4)) + chost = ipsv4[i].String() + } else { + if len(ips) == 0 { + return fmt.Errorf("[SERV] No IPs resolved for the given hostname") + return nil + } + chost = ips[0].String() + } + } + eachPeer(s.peers, func(p *Peer, v *list.Element) { if p.conn == nil { return } phost, _, _ := net.SplitHostPort(p.conn.RemoteAddr().String()) - ahost, _, _ := net.SplitHostPort(addr) - if phost == ahost { + if phost == chost { alreadyConnected = true + ethutil.Config.Log.Debugf("[SERV] Peer %s already added.\n", chost) return } })