// ResolveUnspecifiedAddress expands an unspecified ip addresses (/ip4/0.0.0.0, /ip6/::) to
// use the known local interfaces. If ifaceAddr is nil, we request interface addresses
// from the network stack. (this is so you can provide a cached value if resolving many addrs)
func ResolveUnspecifiedAddress(resolve ma.Multiaddr, ifaceAddrs []ma.Multiaddr) ([]ma.Multiaddr, error) {
// split address into its components
split := ma.Split(resolve)
// if first component (ip) is not unspecified, use it as is.
if !manet.IsIPUnspecified(split[0]) {
return []ma.Multiaddr{resolve}, nil
}
out := make([]ma.Multiaddr, 0, len(ifaceAddrs))
for _, ia := range ifaceAddrs {
// must match the first protocol to be resolve.
if ia.Protocols()[0].Code != resolve.Protocols()[0].Code {
continue
}
split[0] = ia
joined := ma.Join(split...)
out = append(out, joined)
log.Debug("adding resolved addr:", resolve, joined, out)
}
if len(out) < 1 {
return nil, fmt.Errorf("failed to resolve: %s", resolve)
}
return out, nil
}
// AddrMatch returns the Multiaddrs that match the protocol stack on addr
func AddrMatch(match ma.Multiaddr, addrs []ma.Multiaddr) []ma.Multiaddr {
// we should match transports entirely.
p1s := match.Protocols()
out := make([]ma.Multiaddr, 0, len(addrs))
for _, a := range addrs {
p2s := a.Protocols()
if len(p1s) != len(p2s) {
continue
}
match := true
for i, p2 := range p2s {
if p1s[i].Code != p2.Code {
match = false
break
}
}
if match {
out = append(out, a)
}
}
return out
}
// DialArgs is a convenience function returning arguments for use in net.Dial
func DialArgs(m ma.Multiaddr) (string, string, error) {
if !IsThinWaist(m) {
return "", "", fmt.Errorf("%s is not a 'thin waist' address", m)
}
str := m.String()
parts := strings.Split(str, "/")[1:]
if len(parts) == 2 { // only IP
return parts[0], parts[1], nil
}
network := parts[2]
if parts[2] == "udp" && len(parts) > 4 && parts[4] == "utp" {
network = parts[4]
}
var host string
switch parts[0] {
case "ip4":
network = network + "4"
host = strings.Join([]string{parts[1], parts[3]}, ":")
case "ip6":
network = network + "6"
host = fmt.Sprintf("[%s]:%s", parts[1], parts[3])
}
return network, host, nil
}
func (oas *ObservedAddrSet) Add(addr ma.Multiaddr, observer ma.Multiaddr) {
oas.Lock()
defer oas.Unlock()
// for zero-value.
if oas.addrs == nil {
oas.addrs = make(map[string]*ObservedAddr)
oas.ttl = peer.OwnObservedAddrTTL
}
s := addr.String()
oa, found := oas.addrs[s]
// first time seeing address.
if !found {
oa = &ObservedAddr{
Addr: addr,
SeenBy: make(map[string]struct{}),
}
oas.addrs[s] = oa
}
// mark the observer
oa.SeenBy[observerGroup(observer)] = struct{}{}
oa.LastSeen = time.Now()
}
// 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
}
func addrInAddrs(a ma.Multiaddr, as []ma.Multiaddr) bool {
for _, b := range as {
if a.Equal(b) {
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(observed, expected ma.Multiaddr, listen []ma.Multiaddr) {
if observed.Equal(expected) {
return
}
if !AddrInList(observed, listen) { // probably a nat
log.Warningf(natWarning, observed, listen)
}
}
// rawConnDial dials the underlying net.Conn + manet.Conns
func (d *Dialer) rawConnDial(ctx context.Context, raddr ma.Multiaddr, remote peer.ID) (manet.Conn, error) {
// before doing anything, check we're going to be able to dial.
// we may not support the given address.
if _, _, err := manet.DialArgs(raddr); err != nil {
return nil, err
}
if strings.HasPrefix(raddr.String(), "/ip4/0.0.0.0") {
log.Event(ctx, "connDialZeroAddr", lgbl.Dial("conn", d.LocalPeer, remote, nil, raddr))
return nil, fmt.Errorf("Attempted to connect to zero address: %s", raddr)
}
// get local addr to use.
laddr := pickLocalAddr(d.LocalAddrs, raddr)
logdial := lgbl.Dial("conn", d.LocalPeer, remote, laddr, raddr)
defer log.EventBegin(ctx, "connDialRawConn", logdial).Done()
// make a copy of the manet.Dialer, we may need to change its timeout.
madialer := d.Dialer
if laddr != nil && reuseportIsAvailable() {
// we're perhaps going to dial twice. half the timeout, so we can afford to.
// otherwise our context would expire right after the first dial.
madialer.Dialer.Timeout = (madialer.Dialer.Timeout / 2)
// dial using reuseport.Dialer, because we're probably reusing addrs.
// this is optimistic, as the reuseDial may fail to bind the port.
rpev := log.EventBegin(ctx, "connDialReusePort", logdial)
if nconn, retry, reuseErr := reuseDial(madialer.Dialer, laddr, raddr); reuseErr == nil {
// if it worked, wrap the raw net.Conn with our manet.Conn
logdial["reuseport"] = "success"
rpev.Done()
return manet.WrapNetConn(nconn)
} else if !retry {
// reuseDial is sure this is a legitimate dial failure, not a reuseport failure.
logdial["reuseport"] = "failure"
logdial["error"] = reuseErr
rpev.Done()
return nil, reuseErr
} else {
// this is a failure to reuse port. log it.
logdial["reuseport"] = "retry"
logdial["error"] = reuseErr
rpev.Done()
}
}
defer log.EventBegin(ctx, "connDialManet", logdial).Done()
return madialer.Dial(raddr)
}
// IsIPLoopback returns whether a Multiaddr is a "Loopback" IP address
// This means either /ip4/127.0.0.1 or /ip6/::1
// TODO: differentiate IsIPLoopback and OverIPLoopback
func IsIPLoopback(m ma.Multiaddr) bool {
b := m.Bytes()
// /ip4/127 prefix (_entire_ /8 is loopback...)
if bytes.HasPrefix(b, []byte{ma.P_IP4, 127}) {
return true
}
// /ip6/::1
if IP6Loopback.Equal(m) || IP6LinkLocalLoopback.Equal(m) {
return true
}
return false
}
func addPortMapping(nmgr *natManager, intaddr ma.Multiaddr) {
nat := nmgr.NAT()
if nat == nil {
panic("natManager addPortMapping called without a nat.")
}
// first, check if the port mapping already exists.
for _, mapping := range nat.Mappings() {
if mapping.InternalAddr().Equal(intaddr) {
return // it exists! return.
}
}
ctx := context.TODO()
lm := make(lgbl.DeferredMap)
lm["internalAddr"] = func() interface{} { return intaddr.String() }
defer log.EventBegin(ctx, "natMgrAddPortMappingWait", lm).Done()
select {
case <-nmgr.proc.Closing():
lm["outcome"] = "cancelled"
return // no use.
case <-nmgr.ready: // wait until it's ready.
}
// actually start the port map (sub-event because waiting may take a while)
defer log.EventBegin(ctx, "natMgrAddPortMapping", lm).Done()
// get the nat
m, err := nat.NewMapping(intaddr)
if err != nil {
lm["outcome"] = "failure"
lm["error"] = err
return
}
extaddr, err := m.ExternalAddr()
if err != nil {
lm["outcome"] = "failure"
lm["error"] = err
return
}
lm["outcome"] = "success"
lm["externalAddr"] = func() interface{} { return extaddr.String() }
log.Infof("established nat port mapping: %s <--> %s", intaddr, extaddr)
}
// MultiaddrProtocolsMatch returns whether two multiaddrs match in protocol stacks.
func MultiaddrProtocolsMatch(a, b ma.Multiaddr) bool {
ap := a.Protocols()
bp := b.Protocols()
if len(ap) != len(bp) {
return false
}
for i, api := range ap {
if api.Code != bp[i].Code {
return false
}
}
return true
}
// Dial metadata is metadata for dial events
func Dial(sys string, lid, rid peer.ID, laddr, raddr ma.Multiaddr) DeferredMap {
m := DeferredMap{}
m["subsystem"] = sys
if lid != "" {
m["localPeer"] = func() interface{} { return lid.Pretty() }
}
if laddr != nil {
m["localAddr"] = func() interface{} { return laddr.String() }
}
if rid != "" {
m["remotePeer"] = func() interface{} { return rid.Pretty() }
}
if raddr != nil {
m["remoteAddr"] = func() interface{} { return raddr.String() }
}
return m
}
// NewMapping attemps to construct a mapping on protocol and internal port
// It will also periodically renew the mapping until the returned Mapping
// -- or its parent NAT -- is Closed.
//
// May not succeed, and mappings may change over time;
// NAT devices may not respect our port requests, and even lie.
// Clients should not store the mapped results, but rather always
// poll our object for the latest mappings.
func (nat *NAT) NewMapping(maddr ma.Multiaddr) (Mapping, error) {
if nat == nil {
return nil, fmt.Errorf("no nat available")
}
network, addr, err := manet.DialArgs(maddr)
if err != nil {
return nil, fmt.Errorf("DialArgs failed on addr:", maddr.String())
}
switch network {
case "tcp", "tcp4", "tcp6":
network = "tcp"
case "udp", "udp4", "udp6":
network = "udp"
default:
return nil, fmt.Errorf("transport not supported by NAT: %s", network)
}
intports := strings.Split(addr, ":")[1]
intport, err := strconv.Atoi(intports)
if err != nil {
return nil, err
}
m := &mapping{
nat: nat,
proto: network,
intport: intport,
intaddr: maddr,
}
m.proc = goprocess.WithTeardown(func() error {
nat.rmMapping(m)
return nil
})
nat.addMapping(m)
m.proc.AddChild(periodic.Every(MappingDuration/3, func(worker goprocess.Process) {
nat.establishMapping(m)
}))
// do it once synchronously, so first mapping is done right away, and before exiting,
// allowing users -- in the optimistic case -- to use results right after.
nat.establishMapping(m)
return m, nil
}
func outfmt(m ma.Multiaddr) string {
switch format {
case "string":
return m.String()
case "slice":
return fmt.Sprintf("%v", m.Bytes())
case "bytes":
return string(m.Bytes())
case "hex":
return "0x" + hex.EncodeToString(m.Bytes())
}
die("error: invalid format", format)
return ""
}
// AddrUsable returns whether our network can use this addr.
// We only use the transports in SupportedTransportStrings,
// and we do not link local addresses. Loopback is ok
// as we need to be able to connect to multiple ipfs nodes
// in the same machine.
func AddrUsable(a ma.Multiaddr, partial bool) bool {
if a == nil {
return false
}
if !AddrOverNonLocalIP(a) {
return false
}
// test the address protocol list is in SupportedTransportProtocols
matches := func(supported, test []ma.Protocol) bool {
if len(test) > len(supported) {
return false
}
// when partial, it's ok if test < supported.
if !partial && len(supported) != len(test) {
return false
}
for i := range test {
if supported[i].Code != test[i].Code {
return false
}
}
return true
}
transport := a.Protocols()
for _, supported := range SupportedTransportProtocols {
if matches(supported, transport) {
return true
}
}
return false
}
// IsThinWaist returns whether a Multiaddr starts with "Thin Waist" Protocols.
// This means: /{IP4, IP6}[/{TCP, UDP}]
func IsThinWaist(m ma.Multiaddr) bool {
p := m.Protocols()
// nothing? not even a waist.
if len(p) == 0 {
return false
}
if p[0].Code != ma.P_IP4 && p[0].Code != ma.P_IP6 {
return false
}
// only IP? still counts.
if len(p) == 1 {
return true
}
switch p[1].Code {
case ma.P_TCP, ma.P_UDP, ma.P_IP4, ma.P_IP6:
return true
default:
return false
}
}
// IP6 Link Local addresses are non routable. The prefix is technically
// fe80::/10, but we test fe80::/16 for simplicity (no need to mask).
// So far, no hardware interfaces exist long enough to use those 2 bits.
// Send a PR if there is.
func IsIP6LinkLocal(m ma.Multiaddr) bool {
return bytes.HasPrefix(m.Bytes(), []byte{ma.P_IP6, 0xfe, 0x80})
}