status-go/vendor/github.com/huin/goupnp/network.go

76 lines
1.8 KiB
Go

package goupnp
import (
"io"
"net"
"github.com/huin/goupnp/httpu"
)
// httpuClient creates a HTTPU client that multiplexes to all multicast-capable
// IPv4 addresses on the host. Returns a function to clean up once the client is
// no longer required.
func httpuClient() (httpu.ClientInterface, func(), error) {
addrs, err := localIPv4MCastAddrs()
if err != nil {
return nil, nil, ctxError(err, "requesting host IPv4 addresses")
}
closers := make([]io.Closer, 0, len(addrs))
delegates := make([]httpu.ClientInterface, 0, len(addrs))
for _, addr := range addrs {
c, err := httpu.NewHTTPUClientAddr(addr)
if err != nil {
return nil, nil, ctxErrorf(err,
"creating HTTPU client for address %s", addr)
}
closers = append(closers, c)
delegates = append(delegates, c)
}
closer := func() {
for _, c := range closers {
c.Close()
}
}
return httpu.NewMultiClient(delegates), closer, nil
}
// localIPv2MCastAddrs returns the set of IPv4 addresses on multicast-able
// network interfaces.
func localIPv4MCastAddrs() ([]string, error) {
ifaces, err := net.Interfaces()
if err != nil {
return nil, ctxError(err, "requesting host interfaces")
}
// Find the set of addresses to listen on.
var addrs []string
for _, iface := range ifaces {
if iface.Flags&net.FlagMulticast == 0 || iface.Flags&net.FlagLoopback != 0 || iface.Flags&net.FlagUp == 0 {
// Does not support multicast or is a loopback address.
continue
}
ifaceAddrs, err := iface.Addrs()
if err != nil {
return nil, ctxErrorf(err,
"finding addresses on interface %s", iface.Name)
}
for _, netAddr := range ifaceAddrs {
addr, ok := netAddr.(*net.IPNet)
if !ok {
// Not an IPNet address.
continue
}
if addr.IP.To4() == nil {
// Not IPv4.
continue
}
addrs = append(addrs, addr.IP.String())
}
}
return addrs, nil
}