status-go/vendor/github.com/libp2p/go-nat/natpmp.go

133 lines
2.6 KiB
Go

package nat
import (
"context"
"net"
"time"
natpmp "github.com/jackpal/go-nat-pmp"
)
var (
_ NAT = (*natpmpNAT)(nil)
)
func discoverNATPMP(ctx context.Context) <-chan NAT {
res := make(chan NAT, 1)
ip, err := getDefaultGateway()
if err != nil {
return nil
}
go func() {
defer close(res)
// Unfortunately, we can't actually _stop_ the natpmp
// library. However, we can at least close _our_ channel
// and walk away.
select {
case client, ok := <-discoverNATPMPWithAddr(ip):
if ok {
res <- &natpmpNAT{client, ip, make(map[int]int)}
}
case <-ctx.Done():
}
}()
return res
}
func discoverNATPMPWithAddr(ip net.IP) <-chan *natpmp.Client {
res := make(chan *natpmp.Client, 1)
go func() {
defer close(res)
client := natpmp.NewClient(ip)
_, err := client.GetExternalAddress()
if err != nil {
return
}
res <- client
}()
return res
}
type natpmpNAT struct {
c *natpmp.Client
gateway net.IP
ports map[int]int
}
func (n *natpmpNAT) GetDeviceAddress() (addr net.IP, err error) {
return n.gateway, nil
}
func (n *natpmpNAT) GetInternalAddress() (addr net.IP, err error) {
ifaces, err := net.Interfaces()
if err != nil {
return nil, err
}
for _, iface := range ifaces {
addrs, err := iface.Addrs()
if err != nil {
return nil, err
}
for _, addr := range addrs {
switch x := addr.(type) {
case *net.IPNet:
if x.Contains(n.gateway) {
return x.IP, nil
}
}
}
}
return nil, ErrNoInternalAddress
}
func (n *natpmpNAT) GetExternalAddress() (addr net.IP, err error) {
res, err := n.c.GetExternalAddress()
if err != nil {
return nil, err
}
d := res.ExternalIPAddress
return net.IPv4(d[0], d[1], d[2], d[3]), nil
}
func (n *natpmpNAT) AddPortMapping(_ context.Context, protocol string, internalPort int, _ string, timeout time.Duration) (int, error) {
var (
err error
)
timeoutInSeconds := int(timeout / time.Second)
if externalPort := n.ports[internalPort]; externalPort > 0 {
_, err = n.c.AddPortMapping(protocol, internalPort, externalPort, timeoutInSeconds)
if err == nil {
n.ports[internalPort] = externalPort
return externalPort, nil
}
}
for i := 0; i < 3; i++ {
externalPort := randomPort()
_, err = n.c.AddPortMapping(protocol, internalPort, externalPort, timeoutInSeconds)
if err == nil {
n.ports[internalPort] = externalPort
return externalPort, nil
}
}
return 0, err
}
func (n *natpmpNAT) DeletePortMapping(_ context.Context, _ string, internalPort int) (err error) {
delete(n.ports, internalPort)
return nil
}
func (n *natpmpNAT) Type() string {
return "NAT-PMP"
}