kubo/net/swarm/addr.go
2014-12-17 23:25:40 -08:00

125 lines
3.6 KiB
Go

package swarm
import (
conn "github.com/jbenet/go-ipfs/net/conn"
eventlog "github.com/jbenet/go-ipfs/util/eventlog"
context "github.com/jbenet/go-ipfs/Godeps/_workspace/src/code.google.com/p/go.net/context"
ma "github.com/jbenet/go-ipfs/Godeps/_workspace/src/github.com/jbenet/go-multiaddr"
manet "github.com/jbenet/go-ipfs/Godeps/_workspace/src/github.com/jbenet/go-multiaddr-net"
)
// ListenAddresses returns a list of addresses at which this swarm listens.
func (s *Swarm) ListenAddresses() []ma.Multiaddr {
listeners := s.swarm.Listeners()
addrs := make([]ma.Multiaddr, 0, len(listeners))
for _, l := range listeners {
if l2, ok := l.NetListener().(conn.Listener); ok {
addrs = append(addrs, l2.Multiaddr())
}
}
return addrs
}
// InterfaceListenAddresses returns a list of addresses at which this swarm
// listens. It expands "any interface" addresses (/ip4/0.0.0.0, /ip6/::) to
// use the known local interfaces.
func InterfaceListenAddresses(s *Swarm) ([]ma.Multiaddr, error) {
return resolveUnspecifiedAddresses(s.ListenAddresses())
}
// resolveUnspecifiedAddresses expands unspecified ip addresses (/ip4/0.0.0.0, /ip6/::) to
// use the known local interfaces.
func resolveUnspecifiedAddresses(unspecifiedAddrs []ma.Multiaddr) ([]ma.Multiaddr, error) {
var outputAddrs []ma.Multiaddr
// todo optimize: only fetch these if we have a "any" addr.
ifaceAddrs, err := interfaceAddresses()
if err != nil {
return nil, err
}
for _, a := range unspecifiedAddrs {
// split address into its components
split := ma.Split(a)
// if first component (ip) is not unspecified, use it as is.
if !manet.IsIPUnspecified(split[0]) {
outputAddrs = append(outputAddrs, a)
continue
}
// unspecified? add one address per interface.
for _, ia := range ifaceAddrs {
split[0] = ia
joined := ma.Join(split...)
outputAddrs = append(outputAddrs, joined)
}
}
log.Event(context.TODO(), "interfaceListenAddresses", func() eventlog.Loggable {
var addrs []string
for _, addr := range outputAddrs {
addrs = append(addrs, addr.String())
}
return eventlog.Metadata{"addresses": addrs}
}())
log.Debug("InterfaceListenAddresses:", outputAddrs)
return outputAddrs, nil
}
// interfaceAddresses returns a list of addresses associated with local machine
func interfaceAddresses() ([]ma.Multiaddr, error) {
maddrs, err := manet.InterfaceMultiaddrs()
if err != nil {
return nil, err
}
var nonLoopback []ma.Multiaddr
for _, a := range maddrs {
if !manet.IsIPLoopback(a) {
nonLoopback = append(nonLoopback, a)
}
}
return nonLoopback, nil
}
// addrInList returns whether or not an address is part of a list.
// this is useful to check if NAT is happening (or other bugs?)
func addrInList(addr ma.Multiaddr, list []ma.Multiaddr) bool {
for _, addr2 := range list {
if addr.Equal(addr2) {
return true
}
}
return false
}
// checkNATWarning checks if our observed addresses differ. if so,
// informs the user that certain things might not work yet
func checkNATWarning(s *Swarm, observed ma.Multiaddr, expected ma.Multiaddr) {
if observed.Equal(expected) {
return
}
listen, err := InterfaceListenAddresses(s)
if err != nil {
log.Errorf("Error retrieving swarm.InterfaceListenAddresses: %s", err)
return
}
if !addrInList(observed, listen) { // probably a nat
log.Warningf(natWarning, observed, listen)
}
}
const natWarning = `Remote peer observed our address to be: %s
The local addresses are: %s
Thus, connection is going through NAT, and other connections may fail.
IPFS NAT traversal is still under development. Please bug us on github or irc to fix this.
Baby steps: http://jbenet.static.s3.amazonaws.com/271dfcf/baby-steps.gif
`