/
natpmp.go
178 lines (144 loc) · 3.3 KB
/
natpmp.go
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package nat
import (
"net"
"time"
"github.com/jbenet/go-ipfs/Godeps/_workspace/src/github.com/jackpal/go-nat-pmp"
)
var (
_ NAT = (*natpmp_NAT)(nil)
)
func natpmp_PotentialGateways() ([]net.IP, error) {
_, ipNet_10, err := net.ParseCIDR("10.0.0.0/8")
if err != nil {
panic(err)
}
_, ipNet_172_16, err := net.ParseCIDR("172.16.0.0/12")
if err != nil {
panic(err)
}
_, ipNet_192_168, err := net.ParseCIDR("192.168.0.0/16")
if err != nil {
panic(err)
}
ifaces, err := net.Interfaces()
if err != nil {
return nil, err
}
var ips []net.IP
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:
var ipNet *net.IPNet
if ipNet_10.Contains(x.IP) {
ipNet = ipNet_10
} else if ipNet_172_16.Contains(x.IP) {
ipNet = ipNet_172_16
} else if ipNet_192_168.Contains(x.IP) {
ipNet = ipNet_192_168
}
if ipNet != nil {
ip := x.IP.Mask(x.Mask)
ip = ip.To4()
if ip != nil {
ip[3] = ip[3] | 0x01
ips = append(ips, ip)
}
}
}
}
}
if len(ips) == 0 {
return nil, ErrNoNATFound
}
return ips, nil
}
func discoverNATPMP() <-chan NAT {
ips, err := natpmp_PotentialGateways()
if err != nil {
return nil
}
res := make(chan NAT, len(ips))
for _, ip := range ips {
go discoverNATPMPWithAddr(res, ip)
}
return res
}
func discoverNATPMPWithAddr(c chan NAT, ip net.IP) {
client := natpmp.NewClient(ip)
_, err := client.GetExternalAddress()
if err != nil {
return
}
c <- &natpmp_NAT{client, ip, make(map[int]int)}
}
type natpmp_NAT struct {
c *natpmp.Client
gateway net.IP
ports map[int]int
}
func (n *natpmp_NAT) GetDeviceAddress() (addr net.IP, err error) {
return n.gateway, nil
}
func (n *natpmp_NAT) 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 *natpmp_NAT) 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 *natpmp_NAT) AddPortMapping(protocol string, internalPort int, description 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 *natpmp_NAT) DeletePortMapping(protocol string, internalPort int) (err error) {
delete(n.ports, internalPort)
return nil
}
func (n *natpmp_NAT) Type() string {
return "NAT-PMP"
}