Add stun server for ip discovery and flag stun

cmd/shisui/main.go

@@ -13,6 +13,7 @@ import (
 	"slices"
 	"strings"
 	"syscall"
+	"time"
 
 	"os"
 
@@ -249,8 +250,13 @@ func initDiscV5(config Config, conn discover.UDPConn) (*discover.UDPv5, *enode.L
 	}
 
 	localNode := enode.NewLocalNode(nodeDB, config.PrivateKey)
-	localNode.SetFallbackIP(net.IP{127, 0, 0, 1})
+
 	localNode.Set(discover.Tag)
+	listenerAddr := conn.LocalAddr().(*net.UDPAddr)
+	nat := config.Protocol.NAT
+	if nat != nil && !listenerAddr.IP.IsLoopback() {
+		doPortMapping(nat, localNode, listenerAddr)
+	}
 
 	discV5, err := discover.ListenV5(conn, localNode, discCfg)
 	if err != nil {
@@ -259,6 +265,57 @@ func initDiscV5(config Config, conn discover.UDPConn) (*discover.UDPv5, *enode.L
 	return discV5, localNode, nil
 }
 
+func doPortMapping(natm nat.Interface, ln *enode.LocalNode, addr *net.UDPAddr) {
+	const (
+		protocol = "udp"
+		name     = "ethereum discovery"
+	)
+
+	var (
+		intport    = addr.Port
+		extaddr    = &net.UDPAddr{IP: addr.IP, Port: addr.Port}
+		mapTimeout = nat.DefaultMapTimeout
+	)
+	addMapping := func() {
+		// Get the external address.
+		var err error
+		extaddr.IP, err = natm.ExternalIP()
+		if err != nil {
+			log.Debug("Couldn't get external IP", "err", err)
+			return
+		}
+		// Create the mapping.
+		p, err := natm.AddMapping(protocol, extaddr.Port, intport, name, mapTimeout)
+		if err != nil {
+			log.Debug("Couldn't add port mapping", "err", err)
+			return
+		}
+		if p != uint16(extaddr.Port) {
+			extaddr.Port = int(p)
+			log.Info("NAT mapped alternative port")
+		} else {
+			log.Info("NAT mapped port")
+		}
+		// Update IP/port information of the local node.
+		ln.SetStaticIP(extaddr.IP)
+		ln.SetFallbackUDP(extaddr.Port)
+	}
+
+	// Perform mapping once, synchronously.
+	log.Info("Attempting port mapping")
+	addMapping()
+
+	// Refresh the mapping periodically.
+	go func() {
+		refresh := time.NewTimer(mapTimeout)
+		defer refresh.Stop()
+		for range refresh.C {
+			addMapping()
+			refresh.Reset(mapTimeout)
+		}
+	}()
+}
+
 func initHistory(config Config, server *rpc.Server, conn discover.UDPConn, localNode *enode.LocalNode, discV5 *discover.UDPv5) (*history.HistoryNetwork, error) {
 	networkName := portalwire.History.Name()
 	db, err := history.NewDB(config.DataDir, networkName)

cmd/shisui/main_test.go

@@ -0,0 +1,33 @@
+package main
+
+import (
+	"net"
+	"testing"
+
+	"github.com/ethereum/go-ethereum/crypto"
+	"github.com/ethereum/go-ethereum/p2p/enode"
+	"github.com/ethereum/go-ethereum/p2p/nat"
+	"github.com/stretchr/testify/assert"
+)
+
+func newLocalNodeForTesting() (*enode.LocalNode, *enode.DB) {
+	db, _ := enode.OpenDB("")
+	key, _ := crypto.GenerateKey()
+	return enode.NewLocalNode(db, key), db
+}
+
+func TestDoPortMapping(t *testing.T) {
+	nat := nat.ExtIP{33, 44, 55, 66}
+	localNode, _ := newLocalNodeForTesting()
+	listenerAddr := &net.UDPAddr{IP: net.IP{127, 0, 0, 1}, Port: 1234}
+
+	doPortMapping(nat, localNode, listenerAddr)
+
+	assert.Equal(t, localNode.Seq(), uint64(1))
+	assert.Equal(t, localNode.Node().IP(), net.IP{33, 44, 55, 66})
+	assert.Equal(t, localNode.Node().UDP(), 1234)
+	assert.Equal(t, localNode.Node().TCP(), 0)
+
+	_ = localNode.Node().UDP()
+	assert.Equal(t, localNode.Seq(), uint64(2))
+}

cmd/utils/flags.go

@@ -982,7 +982,7 @@ Please note that --` + MetricsHTTPFlag.Name + ` must be set to start the server.
 
 	PortalNATFlag = &cli.StringFlag{
 		Name:     "nat",
-		Usage:    "NAT port mapping mechanism (any|none|upnp|pmp|pmp:<IP>|extip:<IP>)",
+		Usage:    "NAT port mapping mechanism (any|none|upnp|pmp|stun|pmp:<IP>|extip:<IP>|stun:<IP>)",
 		Value:    "any",
 		Category: flags.PortalNetworkCategory,
 	}

go.mod

@@ -56,6 +56,7 @@ require (
 	github.com/olekukonko/tablewriter v0.0.5
 	github.com/optimism-java/utp-go v0.0.0-20240716050942-7583a3d702fd
 	github.com/peterh/liner v1.1.1-0.20190123174540-a2c9a5303de7
+	github.com/pion/stun v0.6.1
 	github.com/protolambda/bls12-381-util v0.1.0
 	github.com/protolambda/zrnt v0.32.2
 	github.com/protolambda/ztyp v0.2.2
@@ -136,6 +137,9 @@ require (
 	github.com/mmcloughlin/addchain v0.4.0 // indirect
 	github.com/naoina/go-stringutil v0.1.0 // indirect
 	github.com/opentracing/opentracing-go v1.1.0 // indirect
+	github.com/pion/dtls/v2 v2.2.7 // indirect
+	github.com/pion/logging v0.2.2 // indirect
+	github.com/pion/transport/v2 v2.2.1 // indirect
 	github.com/pkg/errors v0.9.1 // indirect
 	github.com/pmezard/go-difflib v1.0.0 // indirect
 	github.com/prometheus/client_golang v1.12.0 // indirect

go.sum

@@ -433,6 +433,14 @@ github.com/peterh/liner v1.1.1-0.20190123174540-a2c9a5303de7 h1:oYW+YCJ1pachXTQm
 github.com/peterh/liner v1.1.1-0.20190123174540-a2c9a5303de7/go.mod h1:CRroGNssyjTd/qIG2FyxByd2S8JEAZXBl4qUrZf8GS0=
 github.com/pingcap/errors v0.11.4 h1:lFuQV/oaUMGcD2tqt+01ROSmJs75VG1ToEOkZIZ4nE4=
 github.com/pingcap/errors v0.11.4/go.mod h1:Oi8TUi2kEtXXLMJk9l1cGmz20kV3TaQ0usTwv5KuLY8=
+github.com/pion/dtls/v2 v2.2.7 h1:cSUBsETxepsCSFSxC3mc/aDo14qQLMSL+O6IjG28yV8=
+github.com/pion/dtls/v2 v2.2.7/go.mod h1:8WiMkebSHFD0T+dIU+UeBaoV7kDhOW5oDCzZ7WZ/F9s=
+github.com/pion/logging v0.2.2 h1:M9+AIj/+pxNsDfAT64+MAVgJO0rsyLnoJKCqf//DoeY=
+github.com/pion/logging v0.2.2/go.mod h1:k0/tDVsRCX2Mb2ZEmTqNa7CWsQPc+YYCB7Q+5pahoms=
+github.com/pion/stun v0.6.1 h1:8lp6YejULeHBF8NmV8e2787BogQhduZugh5PdhDyyN4=
+github.com/pion/stun v0.6.1/go.mod h1:/hO7APkX4hZKu/D0f2lHzNyvdkTGtIy3NDmLR7kSz/8=
+github.com/pion/transport/v2 v2.2.1 h1:7qYnCBlpgSJNYMbLCKuSY9KbQdBFoETvPNETv0y4N7c=
+github.com/pion/transport/v2 v2.2.1/go.mod h1:cXXWavvCnFF6McHTft3DWS9iic2Mftcz1Aq29pGcU5g=
 github.com/pkg/browser v0.0.0-20210911075715-681adbf594b8 h1:KoWmjvw+nsYOo29YJK9vDA65RGE3NrOnUtO7a+RF9HU=
 github.com/pkg/browser v0.0.0-20210911075715-681adbf594b8/go.mod h1:HKlIX3XHQyzLZPlr7++PzdhaXEj94dEiJgZDTsxEqUI=
 github.com/pkg/diff v0.0.0-20210226163009-20ebb0f2a09e/go.mod h1:pJLUxLENpZxwdsKMEsNbx1VGcRFpLqf3715MtcvvzbA=
@@ -494,11 +502,17 @@ github.com/status-im/keycard-go v0.2.0 h1:QDLFswOQu1r5jsycloeQh3bVU8n/NatHHaZobt
 github.com/status-im/keycard-go v0.2.0/go.mod h1:wlp8ZLbsmrF6g6WjugPAx+IzoLrkdf9+mHxBEeo3Hbg=
 github.com/stretchr/objx v0.1.0/go.mod h1:HFkY916IF+rwdDfMAkV7OtwuqBVzrE8GR6GFx+wExME=
 github.com/stretchr/objx v0.1.1/go.mod h1:HFkY916IF+rwdDfMAkV7OtwuqBVzrE8GR6GFx+wExME=
+github.com/stretchr/objx v0.4.0/go.mod h1:YvHI0jy2hoMjB+UWwv71VJQ9isScKT/TqJzVSSt89Yw=
+github.com/stretchr/objx v0.5.0/go.mod h1:Yh+to48EsGEfYuaHDzXPcE3xhTkx73EhmCGUpEOglKo=
 github.com/stretchr/testify v1.2.2/go.mod h1:a8OnRcib4nhh0OaRAV+Yts87kKdq0PP7pXfy6kDkUVs=
 github.com/stretchr/testify v1.3.0/go.mod h1:M5WIy9Dh21IEIfnGCwXGc5bZfKNJtfHm1UVUgZn+9EI=
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 github.com/stretchr/testify v1.7.0/go.mod h1:6Fq8oRcR53rry900zMqJjRRixrwX3KX962/h/Wwjteg=
+github.com/stretchr/testify v1.7.1/go.mod h1:6Fq8oRcR53rry900zMqJjRRixrwX3KX962/h/Wwjteg=
+github.com/stretchr/testify v1.8.0/go.mod h1:yNjHg4UonilssWZ8iaSj1OCr/vHnekPRkoO+kdMU+MU=
+github.com/stretchr/testify v1.8.3/go.mod h1:sz/lmYIOXD/1dqDmKjjqLyZ2RngseejIcXlSw2iwfAo=
+github.com/stretchr/testify v1.8.4/go.mod h1:sz/lmYIOXD/1dqDmKjjqLyZ2RngseejIcXlSw2iwfAo=
 github.com/stretchr/testify v1.9.0 h1:HtqpIVDClZ4nwg75+f6Lvsy/wHu+3BoSGCbBAcpTsTg=
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 github.com/supranational/blst v0.3.13 h1:AYeSxdOMacwu7FBmpfloBz5pbFXDmJL33RuwnKtmTjk=
@@ -547,6 +561,7 @@ golang.org/x/crypto v0.0.0-20200622213623-75b288015ac9/go.mod h1:LzIPMQfyMNhhGPh
 golang.org/x/crypto v0.0.0-20200820211705-5c72a883971a/go.mod h1:LzIPMQfyMNhhGPhUkYOs5KpL4U8rLKemX1yGLhDgUto=
 golang.org/x/crypto v0.0.0-20201221181555-eec23a3978ad/go.mod h1:jdWPYTVW3xRLrWPugEBEK3UY2ZEsg3UU495nc5E+M+I=
 golang.org/x/crypto v0.0.0-20210921155107-089bfa567519/go.mod h1:GvvjBRRGRdwPK5ydBHafDWAxML/pGHZbMvKqRZ5+Abc=
+golang.org/x/crypto v0.8.0/go.mod h1:mRqEX+O9/h5TFCrQhkgjo2yKi0yYA+9ecGkdQoHrywE=
 golang.org/x/crypto v0.22.0 h1:g1v0xeRhjcugydODzvb3mEM9SQ0HGp9s/nh3COQ/C30=
 golang.org/x/crypto v0.22.0/go.mod h1:vr6Su+7cTlO45qkww3VDJlzDn0ctJvRgYbC2NvXHt+M=
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@@ -582,6 +597,7 @@ golang.org/x/mod v0.1.1-0.20191107180719-034126e5016b/go.mod h1:QqPTAvyqsEbceGzB
 golang.org/x/mod v0.2.0/go.mod h1:s0Qsj1ACt9ePp/hMypM3fl4fZqREWJwdYDEqhRiZZUA=
 golang.org/x/mod v0.3.0/go.mod h1:s0Qsj1ACt9ePp/hMypM3fl4fZqREWJwdYDEqhRiZZUA=
 golang.org/x/mod v0.6.0-dev.0.20220419223038-86c51ed26bb4/go.mod h1:jJ57K6gSWd91VN4djpZkiMVwK6gcyfeH4XE8wZrZaV4=
+golang.org/x/mod v0.8.0/go.mod h1:iBbtSCu2XBx23ZKBPSOrRkjjQPZFPuis4dIYUhu/chs=
 golang.org/x/mod v0.17.0 h1:zY54UmvipHiNd+pm+m0x9KhZ9hl1/7QNMyxXbc6ICqA=
 golang.org/x/mod v0.17.0/go.mod h1:hTbmBsO62+eylJbnUtE2MGJUyE7QWk4xUqPFrRgJ+7c=
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@@ -620,6 +636,8 @@ golang.org/x/net v0.0.0-20210119194325-5f4716e94777/go.mod h1:m0MpNAwzfU5UDzcl9v
 golang.org/x/net v0.0.0-20210226172049-e18ecbb05110/go.mod h1:m0MpNAwzfU5UDzcl9v0D8zg8gWTRqZa9RBIspLL5mdg=
 golang.org/x/net v0.0.0-20210525063256-abc453219eb5/go.mod h1:9nx3DQGgdP8bBQD5qxJ1jj9UTztislL4KSBs9R2vV5Y=
 golang.org/x/net v0.0.0-20220722155237-a158d28d115b/go.mod h1:XRhObCWvk6IyKnWLug+ECip1KBveYUHfp+8e9klMJ9c=
+golang.org/x/net v0.6.0/go.mod h1:2Tu9+aMcznHK/AK1HMvgo6xiTLG5rD5rZLDS+rp2Bjs=
+golang.org/x/net v0.9.0/go.mod h1:d48xBJpPfHeWQsugry2m+kC02ZBRGRgulfHnEXEuWns=
 golang.org/x/net v0.24.0 h1:1PcaxkF854Fu3+lvBIx5SYn9wRlBzzcnHZSiaFFAb0w=
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 golang.org/x/oauth2 v0.0.0-20180821212333-d2e6202438be/go.mod h1:N/0e6XlmueqKjAGxoOufVs8QHGRruUQn6yWY3a++T0U=
@@ -640,6 +658,7 @@ golang.org/x/sync v0.0.0-20201020160332-67f06af15bc9/go.mod h1:RxMgew5VJxzue5/jJ
 golang.org/x/sync v0.0.0-20201207232520-09787c993a3a/go.mod h1:RxMgew5VJxzue5/jJTE5uejpjVlOe/izrB70Jof72aM=
 golang.org/x/sync v0.0.0-20210220032951-036812b2e83c/go.mod h1:RxMgew5VJxzue5/jJTE5uejpjVlOe/izrB70Jof72aM=
 golang.org/x/sync v0.0.0-20220722155255-886fb9371eb4/go.mod h1:RxMgew5VJxzue5/jJTE5uejpjVlOe/izrB70Jof72aM=
+golang.org/x/sync v0.1.0/go.mod h1:RxMgew5VJxzue5/jJTE5uejpjVlOe/izrB70Jof72aM=
 golang.org/x/sync v0.7.0 h1:YsImfSBoP9QPYL0xyKJPq0gcaJdG3rInoqxTWbfQu9M=
 golang.org/x/sync v0.7.0/go.mod h1:Czt+wKu1gCyEFDUtn0jG5QVvpJ6rzVqr5aXyt9drQfk=
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@@ -699,7 +718,9 @@ golang.org/x/sys v0.0.0-20220722155257-8c9f86f7a55f/go.mod h1:oPkhp1MJrh7nUepCBc
 golang.org/x/sys v0.0.0-20220811171246-fbc7d0a398ab/go.mod h1:oPkhp1MJrh7nUepCBck5+mAzfO9JrbApNNgaTdGDITg=
 golang.org/x/sys v0.0.0-20220908164124-27713097b956/go.mod h1:oPkhp1MJrh7nUepCBck5+mAzfO9JrbApNNgaTdGDITg=
 golang.org/x/sys v0.1.0/go.mod h1:oPkhp1MJrh7nUepCBck5+mAzfO9JrbApNNgaTdGDITg=
+golang.org/x/sys v0.5.0/go.mod h1:oPkhp1MJrh7nUepCBck5+mAzfO9JrbApNNgaTdGDITg=
 golang.org/x/sys v0.6.0/go.mod h1:oPkhp1MJrh7nUepCBck5+mAzfO9JrbApNNgaTdGDITg=
+golang.org/x/sys v0.7.0/go.mod h1:oPkhp1MJrh7nUepCBck5+mAzfO9JrbApNNgaTdGDITg=
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@@ -708,6 +729,8 @@ golang.org/x/sys v0.22.0/go.mod h1:/VUhepiaJMQUp4+oa/7Zr1D23ma6VTLIYjOOTFZPUcA=
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+golang.org/x/term v0.5.0/go.mod h1:jMB1sMXY+tzblOD4FWmEbocvup2/aLOaQEp7JmGp78k=
+golang.org/x/term v0.7.0/go.mod h1:P32HKFT3hSsZrRxla30E9HqToFYAQPCMs/zFMBUFqPY=
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@@ -717,6 +740,8 @@ golang.org/x/text v0.3.5/go.mod h1:5Zoc/QRtKVWzQhOtBMvqHzDpF6irO9z98xDceosuGiQ=
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+golang.org/x/text v0.7.0/go.mod h1:mrYo+phRRbMaCq/xk9113O4dZlRixOauAjOtrjsXDZ8=
+golang.org/x/text v0.9.0/go.mod h1:e1OnstbJyHTd6l/uOt8jFFHp6TRDWZR/bV3emEE/zU8=
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@@ -769,6 +794,7 @@ golang.org/x/tools v0.0.0-20200804011535-6c149bb5ef0d/go.mod h1:njjCfa9FT2d7l9Bc
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+golang.org/x/tools v0.6.0/go.mod h1:Xwgl3UAJ/d3gWutnCtw505GrjyAbvKui8lOU390QaIU=
 golang.org/x/tools v0.20.0 h1:hz/CVckiOxybQvFw6h7b/q80NTr9IUQb4s1IIzW7KNY=
 golang.org/x/tools v0.20.0/go.mod h1:WvitBU7JJf6A4jOdg4S1tviW9bhUxkgeCui/0JHctQg=
 golang.org/x/xerrors v0.0.0-20190717185122-a985d3407aa7/go.mod h1:I/5z698sn9Ka8TeJc9MKroUUfqBBauWjQqLJ2OPfmY0=

p2p/discover/nat.go

@@ -47,6 +47,12 @@ func (p *PortalProtocol) setupPortMapping() {
 		p.localNode.SetStaticIP(ip)
 		go p.consumePortMappingRequests()
 
+	case nat.STUN:
+		// STUN doesn't block, set the IP right away.
+		ip, _ := p.NAT.ExternalIP()
+		p.localNode.SetStaticIP(ip)
+		go p.consumePortMappingRequests()
+
 	default:
 		go p.portMappingLoop()
 	}

p2p/nat/nat.go

@@ -58,7 +58,9 @@ type Interface interface {
 //	"any"                uses the first auto-detected mechanism
 //	"upnp"               uses the Universal Plug and Play protocol
 //	"pmp"                uses NAT-PMP with an auto-detected gateway address
+//	"stun"               uses stun protocol with default stun server address
 //	"pmp:192.168.0.1"    uses NAT-PMP with the given gateway address
+//	"stun:192.168.0.1"   uses stun protocol with stun server address 192.168.0.1
 func Parse(spec string) (Interface, error) {
 	var (
 		before, after, found = strings.Cut(spec, ":")
@@ -85,6 +87,12 @@ func Parse(spec string) (Interface, error) {
 		return UPnP(), nil
 	case "pmp", "natpmp", "nat-pmp":
 		return PMP(ip), nil
+	case "stun":
+		var addr string
+		if len(after) > 1 {
+			addr = after
+		}
+		return NewSTUN(addr), nil
 	default:
 		return nil, fmt.Errorf("unknown mechanism %q", before)
 	}

p2p/nat/nat_stun.go

@@ -0,0 +1,67 @@
+package nat
+
+import (
+	"fmt"
+	"net"
+	"time"
+
+	"github.com/pion/stun"
+)
+
+const STUNDefaultServerAddr = "159.223.0.83:3478"
+
+type STUN struct {
+	serverAddr string
+}
+
+func NewSTUN(serverAddr string) STUN {
+	if serverAddr == "" {
+		serverAddr = STUNDefaultServerAddr
+	}
+	return STUN{serverAddr: serverAddr}
+}
+
+func (s STUN) String() string {
+	return fmt.Sprintf("STUN(%s)", s.serverAddr)
+}
+
+func (STUN) SupportsMapping() bool {
+	return false
+}
+
+func (STUN) AddMapping(protocol string, extport, intport int, name string, lifetime time.Duration) (uint16, error) {
+	return uint16(extport), nil
+}
+
+func (STUN) DeleteMapping(string, int, int) error {
+	return nil
+}
+
+func (s STUN) ExternalIP() (net.IP, error) {
+	conn, err := stun.Dial("udp4", s.serverAddr)
+	if err != nil {
+		return nil, err
+	}
+	defer func() {
+		_ = conn.Close()
+	}()
+
+	message := stun.MustBuild(stun.TransactionID, stun.BindingRequest)
+	var response *stun.Event
+	err = conn.Do(message, func(event stun.Event) {
+		response = &event
+	})
+	if err != nil {
+		return nil, err
+	}
+	if response.Error != nil {
+		return nil, response.Error
+	}
+
+	var mappedAddr stun.XORMappedAddress
+	if err := mappedAddr.GetFrom(response.Message); err != nil {
+		return nil, err
+	}
+
+	return mappedAddr.IP, nil
+}