4007 lines
115 KiB
Go
4007 lines
115 KiB
Go
// Copyright (c) 2019 Tailscale Inc & AUTHORS All rights reserved.
|
|
// Use of this source code is governed by a BSD-style
|
|
// license that can be found in the LICENSE file.
|
|
|
|
// Package magicsock implements a socket that can change its communication path while
|
|
// in use, actively searching for the best way to communicate.
|
|
package magicsock
|
|
|
|
import (
|
|
"bufio"
|
|
"context"
|
|
crand "crypto/rand"
|
|
"encoding/binary"
|
|
"errors"
|
|
"fmt"
|
|
"hash/fnv"
|
|
"math"
|
|
"math/rand"
|
|
"net"
|
|
"os"
|
|
"reflect"
|
|
"runtime"
|
|
"sort"
|
|
"strconv"
|
|
"strings"
|
|
"sync"
|
|
"sync/atomic"
|
|
"time"
|
|
|
|
"go4.org/mem"
|
|
"golang.org/x/crypto/nacl/box"
|
|
"golang.zx2c4.com/wireguard/conn"
|
|
"inet.af/netaddr"
|
|
"tailscale.com/control/controlclient"
|
|
"tailscale.com/derp"
|
|
"tailscale.com/derp/derphttp"
|
|
"tailscale.com/disco"
|
|
"tailscale.com/health"
|
|
"tailscale.com/ipn/ipnstate"
|
|
"tailscale.com/logtail/backoff"
|
|
"tailscale.com/net/dnscache"
|
|
"tailscale.com/net/interfaces"
|
|
"tailscale.com/net/netcheck"
|
|
"tailscale.com/net/netns"
|
|
"tailscale.com/net/portmapper"
|
|
"tailscale.com/net/stun"
|
|
"tailscale.com/syncs"
|
|
"tailscale.com/tailcfg"
|
|
"tailscale.com/tstime"
|
|
"tailscale.com/tstime/mono"
|
|
"tailscale.com/types/key"
|
|
"tailscale.com/types/logger"
|
|
"tailscale.com/types/netmap"
|
|
"tailscale.com/types/nettype"
|
|
"tailscale.com/util/uniq"
|
|
"tailscale.com/version"
|
|
"tailscale.com/wgengine/monitor"
|
|
)
|
|
|
|
// useDerpRoute reports whether magicsock should enable the DERP
|
|
// return path optimization (Issue 150).
|
|
func useDerpRoute() bool {
|
|
if debugUseDerpRouteEnv != "" {
|
|
return debugUseDerpRoute
|
|
}
|
|
ob := controlclient.DERPRouteFlag()
|
|
if v, ok := ob.Get(); ok {
|
|
return v
|
|
}
|
|
return false
|
|
}
|
|
|
|
// peerInfo is all the information magicsock tracks about a particular
|
|
// peer.
|
|
type peerInfo struct {
|
|
ep *endpoint // always non-nil.
|
|
// ipPorts is an inverted version of peerMap.byIPPort (below), so
|
|
// that when we're deleting this node, we can rapidly find out the
|
|
// keys that need deleting from peerMap.byIPPort without having to
|
|
// iterate over every IPPort known for any peer.
|
|
ipPorts map[netaddr.IPPort]bool
|
|
}
|
|
|
|
func newPeerInfo(ep *endpoint) *peerInfo {
|
|
return &peerInfo{
|
|
ep: ep,
|
|
ipPorts: map[netaddr.IPPort]bool{},
|
|
}
|
|
}
|
|
|
|
// peerMap is an index of peerInfos by node (WireGuard) key, disco
|
|
// key, and discovered ip:port endpoints.
|
|
//
|
|
// Doesn't do any locking, all access must be done with Conn.mu held.
|
|
type peerMap struct {
|
|
byNodeKey map[tailcfg.NodeKey]*peerInfo
|
|
byIPPort map[netaddr.IPPort]*peerInfo
|
|
|
|
// nodesOfDisco are contains the set of nodes that are using a
|
|
// DiscoKey. Usually those sets will be just one node.
|
|
nodesOfDisco map[tailcfg.DiscoKey]map[tailcfg.NodeKey]bool
|
|
}
|
|
|
|
func newPeerMap() peerMap {
|
|
return peerMap{
|
|
byNodeKey: map[tailcfg.NodeKey]*peerInfo{},
|
|
byIPPort: map[netaddr.IPPort]*peerInfo{},
|
|
nodesOfDisco: map[tailcfg.DiscoKey]map[tailcfg.NodeKey]bool{},
|
|
}
|
|
}
|
|
|
|
// nodeCount returns the number of nodes currently in m.
|
|
func (m *peerMap) nodeCount() int {
|
|
return len(m.byNodeKey)
|
|
}
|
|
|
|
// anyEndpointForDiscoKey reports whether there exists any
|
|
// peers in the netmap with dk as their DiscoKey.
|
|
func (m *peerMap) anyEndpointForDiscoKey(dk tailcfg.DiscoKey) bool {
|
|
return len(m.nodesOfDisco[dk]) > 0
|
|
}
|
|
|
|
// endpointForNodeKey returns the endpoint for nk, or nil if
|
|
// nk is not known to us.
|
|
func (m *peerMap) endpointForNodeKey(nk tailcfg.NodeKey) (ep *endpoint, ok bool) {
|
|
if nk.IsZero() {
|
|
return nil, false
|
|
}
|
|
if info, ok := m.byNodeKey[nk]; ok {
|
|
return info.ep, true
|
|
}
|
|
return nil, false
|
|
}
|
|
|
|
// endpointForIPPort returns the endpoint for the peer we
|
|
// believe to be at ipp, or nil if we don't know of any such peer.
|
|
func (m *peerMap) endpointForIPPort(ipp netaddr.IPPort) (ep *endpoint, ok bool) {
|
|
if info, ok := m.byIPPort[ipp]; ok {
|
|
return info.ep, true
|
|
}
|
|
return nil, false
|
|
}
|
|
|
|
// forEachEndpoint invokes f on every endpoint in m.
|
|
func (m *peerMap) forEachEndpoint(f func(ep *endpoint)) {
|
|
for _, pi := range m.byNodeKey {
|
|
f(pi.ep)
|
|
}
|
|
}
|
|
|
|
// forEachEndpointWithDiscoKey invokes f on every endpoint in m
|
|
// that has the provided DiscoKey.
|
|
func (m *peerMap) forEachEndpointWithDiscoKey(dk tailcfg.DiscoKey, f func(ep *endpoint)) {
|
|
for nk := range m.nodesOfDisco[dk] {
|
|
pi, ok := m.byNodeKey[nk]
|
|
if !ok {
|
|
// Unexpected. Data structures would have to
|
|
// be out of sync. But we don't have a logger
|
|
// here to log [unexpected], so just skip.
|
|
// Maybe log later once peerMap is merged back
|
|
// into Conn.
|
|
continue
|
|
}
|
|
f(pi.ep)
|
|
}
|
|
}
|
|
|
|
// upsertEndpoint stores endpoint in the peerInfo for
|
|
// ep.publicKey, and updates indexes. m must already have a
|
|
// tailcfg.Node for ep.publicKey.
|
|
func (m *peerMap) upsertEndpoint(ep *endpoint) {
|
|
pi := m.byNodeKey[ep.publicKey]
|
|
if pi == nil {
|
|
pi = newPeerInfo(ep)
|
|
m.byNodeKey[ep.publicKey] = pi
|
|
} else {
|
|
old := pi.ep
|
|
pi.ep = ep
|
|
if old.discoKey != ep.discoKey {
|
|
delete(m.nodesOfDisco[old.discoKey], ep.publicKey)
|
|
}
|
|
}
|
|
if !ep.discoKey.IsZero() {
|
|
set := m.nodesOfDisco[ep.discoKey]
|
|
if set == nil {
|
|
set = map[tailcfg.NodeKey]bool{}
|
|
m.nodesOfDisco[ep.discoKey] = set
|
|
}
|
|
set[ep.publicKey] = true
|
|
}
|
|
}
|
|
|
|
// setNodeKeyForIPPort makes future peer lookups by ipp return the
|
|
// same endpoint as a lookup by nk.
|
|
//
|
|
// This should only be called with a fully verified mapping of ipp to
|
|
// nk, because calling this function defines the endpoint we hand to
|
|
// WireGuard for packets received from ipp.
|
|
func (m *peerMap) setNodeKeyForIPPort(ipp netaddr.IPPort, nk tailcfg.NodeKey) {
|
|
if pi := m.byIPPort[ipp]; pi != nil {
|
|
delete(pi.ipPorts, ipp)
|
|
delete(m.byIPPort, ipp)
|
|
}
|
|
if pi, ok := m.byNodeKey[nk]; ok {
|
|
pi.ipPorts[ipp] = true
|
|
m.byIPPort[ipp] = pi
|
|
}
|
|
}
|
|
|
|
// deleteEndpoint deletes the peerInfo associated with ep, and
|
|
// updates indexes.
|
|
func (m *peerMap) deleteEndpoint(ep *endpoint) {
|
|
if ep == nil {
|
|
return
|
|
}
|
|
ep.stopAndReset()
|
|
pi := m.byNodeKey[ep.publicKey]
|
|
delete(m.nodesOfDisco[ep.discoKey], ep.publicKey)
|
|
delete(m.byNodeKey, ep.publicKey)
|
|
if pi == nil {
|
|
// Kneejerk paranoia from earlier issue 2801.
|
|
// Unexpected. But no logger plumbed here to log so.
|
|
return
|
|
}
|
|
for ip := range pi.ipPorts {
|
|
delete(m.byIPPort, ip)
|
|
}
|
|
}
|
|
|
|
// A Conn routes UDP packets and actively manages a list of its endpoints.
|
|
// It implements wireguard/conn.Bind.
|
|
type Conn struct {
|
|
// This block mirrors the contents and field order of the Options
|
|
// struct. Initialized once at construction, then constant.
|
|
|
|
logf logger.Logf
|
|
epFunc func([]tailcfg.Endpoint)
|
|
derpActiveFunc func()
|
|
idleFunc func() time.Duration // nil means unknown
|
|
testOnlyPacketListener nettype.PacketListener
|
|
noteRecvActivity func(tailcfg.NodeKey) // or nil, see Options.NoteRecvActivity
|
|
|
|
// ================================================================
|
|
// No locking required to access these fields, either because
|
|
// they're static after construction, or are wholly owned by a
|
|
// single goroutine.
|
|
|
|
connCtx context.Context // closed on Conn.Close
|
|
connCtxCancel func() // closes connCtx
|
|
donec <-chan struct{} // connCtx.Done()'s to avoid context.cancelCtx.Done()'s mutex per call
|
|
|
|
// pconn4 and pconn6 are the underlying UDP sockets used to
|
|
// send/receive packets for wireguard and other magicsock
|
|
// protocols.
|
|
pconn4 *RebindingUDPConn
|
|
pconn6 *RebindingUDPConn
|
|
|
|
// netChecker is the prober that discovers local network
|
|
// conditions, including the closest DERP relay and NAT mappings.
|
|
netChecker *netcheck.Client
|
|
|
|
// portMapper is the NAT-PMP/PCP/UPnP prober/client, for requesting
|
|
// port mappings from NAT devices.
|
|
portMapper *portmapper.Client
|
|
|
|
// stunReceiveFunc holds the current STUN packet processing func.
|
|
// Its Loaded value is always non-nil.
|
|
stunReceiveFunc atomic.Value // of func(p []byte, fromAddr *net.UDPAddr)
|
|
|
|
// derpRecvCh is used by receiveDERP to read DERP messages.
|
|
derpRecvCh chan derpReadResult
|
|
|
|
// bind is the wireguard-go conn.Bind for Conn.
|
|
bind *connBind
|
|
|
|
// ippEndpoint4 and ippEndpoint6 are owned by receiveIPv4 and
|
|
// receiveIPv6, respectively, to cache an IPPort->endpoint for
|
|
// hot flows.
|
|
ippEndpoint4, ippEndpoint6 ippEndpointCache
|
|
|
|
// ============================================================
|
|
// Fields that must be accessed via atomic load/stores.
|
|
|
|
// noV4 and noV6 are whether IPv4 and IPv6 are known to be
|
|
// missing. They're only used to suppress log spam. The name
|
|
// is named negatively because in early start-up, we don't yet
|
|
// necessarily have a netcheck.Report and don't want to skip
|
|
// logging.
|
|
noV4, noV6 syncs.AtomicBool
|
|
|
|
// noV4Send is whether IPv4 UDP is known to be unable to transmit
|
|
// at all. This could happen if the socket is in an invalid state
|
|
// (as can happen on darwin after a network link status change).
|
|
noV4Send syncs.AtomicBool
|
|
|
|
// networkUp is whether the network is up (some interface is up
|
|
// with IPv4 or IPv6). It's used to suppress log spam and prevent
|
|
// new connection that'll fail.
|
|
networkUp syncs.AtomicBool
|
|
|
|
// havePrivateKey is whether privateKey is non-zero.
|
|
havePrivateKey syncs.AtomicBool
|
|
publicKeyAtomic atomic.Value // of tailcfg.NodeKey (or NodeKey zero value if !havePrivateKey)
|
|
|
|
// port is the preferred port from opts.Port; 0 means auto.
|
|
port syncs.AtomicUint32
|
|
|
|
// ============================================================
|
|
// mu guards all following fields; see userspaceEngine lock ordering rules
|
|
mu sync.Mutex
|
|
muCond *sync.Cond
|
|
|
|
closed bool // Close was called
|
|
|
|
// derpCleanupTimer is the timer that fires to occasionally clean
|
|
// up idle DERP connections. It's only used when there is a non-home
|
|
// DERP connection in use.
|
|
derpCleanupTimer *time.Timer
|
|
|
|
// derpCleanupTimerArmed is whether derpCleanupTimer is
|
|
// scheduled to fire within derpCleanStaleInterval.
|
|
derpCleanupTimerArmed bool
|
|
|
|
// periodicReSTUNTimer, when non-nil, is an AfterFunc timer
|
|
// that will call Conn.doPeriodicSTUN.
|
|
periodicReSTUNTimer *time.Timer
|
|
|
|
// endpointsUpdateActive indicates that updateEndpoints is
|
|
// currently running. It's used to deduplicate concurrent endpoint
|
|
// update requests.
|
|
endpointsUpdateActive bool
|
|
// wantEndpointsUpdate, if non-empty, means that a new endpoints
|
|
// update should begin immediately after the currently-running one
|
|
// completes. It can only be non-empty if
|
|
// endpointsUpdateActive==true.
|
|
wantEndpointsUpdate string // true if non-empty; string is reason
|
|
// lastEndpoints records the endpoints found during the previous
|
|
// endpoint discovery. It's used to avoid duplicate endpoint
|
|
// change notifications.
|
|
lastEndpoints []tailcfg.Endpoint
|
|
|
|
// lastEndpointsTime is the last time the endpoints were updated,
|
|
// even if there was no change.
|
|
lastEndpointsTime time.Time
|
|
|
|
// onEndpointRefreshed are funcs to run (in their own goroutines)
|
|
// when endpoints are refreshed.
|
|
onEndpointRefreshed map[*endpoint]func()
|
|
|
|
// peerSet is the set of peers that are currently configured in
|
|
// WireGuard. These are not used to filter inbound or outbound
|
|
// traffic at all, but only to track what state can be cleaned up
|
|
// in other maps below that are keyed by peer public key.
|
|
peerSet map[key.NodePublic]struct{}
|
|
|
|
// discoPrivate is the private naclbox key used for active
|
|
// discovery traffic. It's created once near (but not during)
|
|
// construction.
|
|
discoPrivate key.Private
|
|
discoPublic tailcfg.DiscoKey // public of discoPrivate
|
|
discoShort string // ShortString of discoPublic (to save logging work later)
|
|
// nodeOfDisco tracks the networkmap Node entity for each peer
|
|
// discovery key.
|
|
peerMap peerMap
|
|
|
|
// discoInfo is the state for an active DiscoKey.
|
|
discoInfo map[tailcfg.DiscoKey]*discoInfo
|
|
|
|
// netInfoFunc is a callback that provides a tailcfg.NetInfo when
|
|
// discovered network conditions change.
|
|
//
|
|
// TODO(danderson): why can't it be set at construction time?
|
|
// There seem to be a few natural places in ipn/local.go to
|
|
// swallow untimely invocations.
|
|
netInfoFunc func(*tailcfg.NetInfo) // nil until set
|
|
// netInfoLast is the NetInfo provided in the last call to
|
|
// netInfoFunc. It's used to deduplicate calls to netInfoFunc.
|
|
//
|
|
// TODO(danderson): should all the deduping happen in
|
|
// ipn/local.go? We seem to be doing dedupe at several layers, and
|
|
// magicsock could do with any complexity reduction it can get.
|
|
netInfoLast *tailcfg.NetInfo
|
|
|
|
derpMap *tailcfg.DERPMap // nil (or zero regions/nodes) means DERP is disabled
|
|
netMap *netmap.NetworkMap
|
|
privateKey key.NodePrivate // WireGuard private key for this node
|
|
everHadKey bool // whether we ever had a non-zero private key
|
|
myDerp int // nearest DERP region ID; 0 means none/unknown
|
|
derpStarted chan struct{} // closed on first connection to DERP; for tests & cleaner Close
|
|
activeDerp map[int]activeDerp // DERP regionID -> connection to a node in that region
|
|
prevDerp map[int]*syncs.WaitGroupChan
|
|
|
|
// derpRoute contains optional alternate routes to use as an
|
|
// optimization instead of contacting a peer via their home
|
|
// DERP connection. If they sent us a message on a different
|
|
// DERP connection (which should really only be on our DERP
|
|
// home connection, or what was once our home), then we
|
|
// remember that route here to optimistically use instead of
|
|
// creating a new DERP connection back to their home.
|
|
derpRoute map[key.NodePublic]derpRoute
|
|
|
|
// peerLastDerp tracks which DERP node we last used to speak with a
|
|
// peer. It's only used to quiet logging, so we only log on change.
|
|
peerLastDerp map[key.NodePublic]int
|
|
}
|
|
|
|
// derpRoute is a route entry for a public key, saying that a certain
|
|
// peer should be available at DERP node derpID, as long as the
|
|
// current connection for that derpID is dc. (but dc should not be
|
|
// used to write directly; it's owned by the read/write loops)
|
|
type derpRoute struct {
|
|
derpID int
|
|
dc *derphttp.Client // don't use directly; see comment above
|
|
}
|
|
|
|
// removeDerpPeerRoute removes a DERP route entry previously added by addDerpPeerRoute.
|
|
func (c *Conn) removeDerpPeerRoute(peer key.NodePublic, derpID int, dc *derphttp.Client) {
|
|
c.mu.Lock()
|
|
defer c.mu.Unlock()
|
|
r2 := derpRoute{derpID, dc}
|
|
if r, ok := c.derpRoute[peer]; ok && r == r2 {
|
|
delete(c.derpRoute, peer)
|
|
}
|
|
}
|
|
|
|
// addDerpPeerRoute adds a DERP route entry, noting that peer was seen
|
|
// on DERP node derpID, at least on the connection identified by dc.
|
|
// See issue 150 for details.
|
|
func (c *Conn) addDerpPeerRoute(peer key.NodePublic, derpID int, dc *derphttp.Client) {
|
|
c.mu.Lock()
|
|
defer c.mu.Unlock()
|
|
if c.derpRoute == nil {
|
|
c.derpRoute = make(map[key.NodePublic]derpRoute)
|
|
}
|
|
r := derpRoute{derpID, dc}
|
|
c.derpRoute[peer] = r
|
|
}
|
|
|
|
// DerpMagicIP is a fake WireGuard endpoint IP address that means
|
|
// to use DERP. When used, the port number of the WireGuard endpoint
|
|
// is the DERP server number to use.
|
|
//
|
|
// Mnemonic: 3.3.40 are numbers above the keys D, E, R, P.
|
|
const DerpMagicIP = "127.3.3.40"
|
|
|
|
var derpMagicIPAddr = netaddr.MustParseIP(DerpMagicIP)
|
|
|
|
// activeDerp contains fields for an active DERP connection.
|
|
type activeDerp struct {
|
|
c *derphttp.Client
|
|
cancel context.CancelFunc
|
|
writeCh chan<- derpWriteRequest
|
|
// lastWrite is the time of the last request for its write
|
|
// channel (currently even if there was no write).
|
|
// It is always non-nil and initialized to a non-zero Time.
|
|
lastWrite *time.Time
|
|
createTime time.Time
|
|
}
|
|
|
|
// Options contains options for Listen.
|
|
type Options struct {
|
|
// Logf optionally provides a log function to use.
|
|
// Must not be nil.
|
|
Logf logger.Logf
|
|
|
|
// Port is the port to listen on.
|
|
// Zero means to pick one automatically.
|
|
Port uint16
|
|
|
|
// EndpointsFunc optionally provides a func to be called when
|
|
// endpoints change. The called func does not own the slice.
|
|
EndpointsFunc func([]tailcfg.Endpoint)
|
|
|
|
// DERPActiveFunc optionally provides a func to be called when
|
|
// a connection is made to a DERP server.
|
|
DERPActiveFunc func()
|
|
|
|
// IdleFunc optionally provides a func to return how long
|
|
// it's been since a TUN packet was sent or received.
|
|
IdleFunc func() time.Duration
|
|
|
|
// TestOnlyPacketListener optionally specifies how to create PacketConns.
|
|
// Only used by tests.
|
|
TestOnlyPacketListener nettype.PacketListener
|
|
|
|
// NoteRecvActivity, if provided, is a func for magicsock to call
|
|
// whenever it receives a packet from a a peer if it's been more
|
|
// than ~10 seconds since the last one. (10 seconds is somewhat
|
|
// arbitrary; the sole user just doesn't need or want it called on
|
|
// every packet, just every minute or two for Wireguard timeouts,
|
|
// and 10 seconds seems like a good trade-off between often enough
|
|
// and not too often.)
|
|
// The provided func is likely to call back into
|
|
// Conn.ParseEndpoint, which acquires Conn.mu. As such, you should
|
|
// not hold Conn.mu while calling it.
|
|
NoteRecvActivity func(tailcfg.NodeKey)
|
|
|
|
// LinkMonitor is the link monitor to use.
|
|
// With one, the portmapper won't be used.
|
|
LinkMonitor *monitor.Mon
|
|
}
|
|
|
|
func (o *Options) logf() logger.Logf {
|
|
if o.Logf == nil {
|
|
panic("must provide magicsock.Options.logf")
|
|
}
|
|
return o.Logf
|
|
}
|
|
|
|
func (o *Options) endpointsFunc() func([]tailcfg.Endpoint) {
|
|
if o == nil || o.EndpointsFunc == nil {
|
|
return func([]tailcfg.Endpoint) {}
|
|
}
|
|
return o.EndpointsFunc
|
|
}
|
|
|
|
func (o *Options) derpActiveFunc() func() {
|
|
if o == nil || o.DERPActiveFunc == nil {
|
|
return func() {}
|
|
}
|
|
return o.DERPActiveFunc
|
|
}
|
|
|
|
// newConn is the error-free, network-listening-side-effect-free based
|
|
// of NewConn. Mostly for tests.
|
|
func newConn() *Conn {
|
|
c := &Conn{
|
|
derpRecvCh: make(chan derpReadResult),
|
|
derpStarted: make(chan struct{}),
|
|
peerLastDerp: make(map[key.NodePublic]int),
|
|
peerMap: newPeerMap(),
|
|
discoInfo: make(map[tailcfg.DiscoKey]*discoInfo),
|
|
}
|
|
c.bind = &connBind{Conn: c, closed: true}
|
|
c.muCond = sync.NewCond(&c.mu)
|
|
c.networkUp.Set(true) // assume up until told otherwise
|
|
return c
|
|
}
|
|
|
|
// NewConn creates a magic Conn listening on opts.Port.
|
|
// As the set of possible endpoints for a Conn changes, the
|
|
// callback opts.EndpointsFunc is called.
|
|
//
|
|
// It doesn't start doing anything until Start is called.
|
|
func NewConn(opts Options) (*Conn, error) {
|
|
c := newConn()
|
|
c.port.Set(uint32(opts.Port))
|
|
c.logf = opts.logf()
|
|
c.epFunc = opts.endpointsFunc()
|
|
c.derpActiveFunc = opts.derpActiveFunc()
|
|
c.idleFunc = opts.IdleFunc
|
|
c.testOnlyPacketListener = opts.TestOnlyPacketListener
|
|
c.noteRecvActivity = opts.NoteRecvActivity
|
|
c.portMapper = portmapper.NewClient(logger.WithPrefix(c.logf, "portmapper: "), c.onPortMapChanged)
|
|
if opts.LinkMonitor != nil {
|
|
c.portMapper.SetGatewayLookupFunc(opts.LinkMonitor.GatewayAndSelfIP)
|
|
}
|
|
|
|
if err := c.initialBind(); err != nil {
|
|
return nil, err
|
|
}
|
|
|
|
c.connCtx, c.connCtxCancel = context.WithCancel(context.Background())
|
|
c.donec = c.connCtx.Done()
|
|
c.netChecker = &netcheck.Client{
|
|
Logf: logger.WithPrefix(c.logf, "netcheck: "),
|
|
GetSTUNConn4: func() netcheck.STUNConn { return c.pconn4 },
|
|
SkipExternalNetwork: inTest(),
|
|
PortMapper: c.portMapper,
|
|
}
|
|
|
|
if c.pconn6 != nil {
|
|
c.netChecker.GetSTUNConn6 = func() netcheck.STUNConn { return c.pconn6 }
|
|
}
|
|
|
|
c.ignoreSTUNPackets()
|
|
|
|
return c, nil
|
|
}
|
|
|
|
// ignoreSTUNPackets sets a STUN packet processing func that does nothing.
|
|
func (c *Conn) ignoreSTUNPackets() {
|
|
c.stunReceiveFunc.Store(func([]byte, netaddr.IPPort) {})
|
|
}
|
|
|
|
// doPeriodicSTUN is called (in a new goroutine) by
|
|
// periodicReSTUNTimer when periodic STUNs are active.
|
|
func (c *Conn) doPeriodicSTUN() { c.ReSTUN("periodic") }
|
|
|
|
func (c *Conn) stopPeriodicReSTUNTimerLocked() {
|
|
if t := c.periodicReSTUNTimer; t != nil {
|
|
t.Stop()
|
|
c.periodicReSTUNTimer = nil
|
|
}
|
|
}
|
|
|
|
// c.mu must NOT be held.
|
|
func (c *Conn) updateEndpoints(why string) {
|
|
defer func() {
|
|
c.mu.Lock()
|
|
defer c.mu.Unlock()
|
|
why := c.wantEndpointsUpdate
|
|
c.wantEndpointsUpdate = ""
|
|
if !c.closed {
|
|
if why != "" {
|
|
go c.updateEndpoints(why)
|
|
return
|
|
}
|
|
if c.shouldDoPeriodicReSTUNLocked() {
|
|
// Pick a random duration between 20
|
|
// and 26 seconds (just under 30s, a
|
|
// common UDP NAT timeout on Linux,
|
|
// etc)
|
|
d := tstime.RandomDurationBetween(20*time.Second, 26*time.Second)
|
|
if t := c.periodicReSTUNTimer; t != nil {
|
|
if debugReSTUNStopOnIdle {
|
|
c.logf("resetting existing periodicSTUN to run in %v", d)
|
|
}
|
|
t.Reset(d)
|
|
} else {
|
|
if debugReSTUNStopOnIdle {
|
|
c.logf("scheduling periodicSTUN to run in %v", d)
|
|
}
|
|
c.periodicReSTUNTimer = time.AfterFunc(d, c.doPeriodicSTUN)
|
|
}
|
|
} else {
|
|
if debugReSTUNStopOnIdle {
|
|
c.logf("periodic STUN idle")
|
|
}
|
|
c.stopPeriodicReSTUNTimerLocked()
|
|
}
|
|
}
|
|
c.endpointsUpdateActive = false
|
|
c.muCond.Broadcast()
|
|
}()
|
|
c.logf("[v1] magicsock: starting endpoint update (%s)", why)
|
|
if c.noV4Send.Get() && runtime.GOOS != "js" {
|
|
c.mu.Lock()
|
|
closed := c.closed
|
|
c.mu.Unlock()
|
|
if !closed {
|
|
c.logf("magicsock: last netcheck reported send error. Rebinding.")
|
|
c.Rebind()
|
|
}
|
|
}
|
|
|
|
endpoints, err := c.determineEndpoints(c.connCtx)
|
|
if err != nil {
|
|
c.logf("magicsock: endpoint update (%s) failed: %v", why, err)
|
|
// TODO(crawshaw): are there any conditions under which
|
|
// we should trigger a retry based on the error here?
|
|
return
|
|
}
|
|
|
|
if c.setEndpoints(endpoints) {
|
|
c.logEndpointChange(endpoints)
|
|
c.epFunc(endpoints)
|
|
}
|
|
}
|
|
|
|
// setEndpoints records the new endpoints, reporting whether they're changed.
|
|
// It takes ownership of the slice.
|
|
func (c *Conn) setEndpoints(endpoints []tailcfg.Endpoint) (changed bool) {
|
|
anySTUN := false
|
|
for _, ep := range endpoints {
|
|
if ep.Type == tailcfg.EndpointSTUN {
|
|
anySTUN = true
|
|
}
|
|
}
|
|
|
|
c.mu.Lock()
|
|
defer c.mu.Unlock()
|
|
|
|
if !anySTUN && c.derpMap == nil && !inTest() {
|
|
// Don't bother storing or reporting this yet. We
|
|
// don't have a DERP map or any STUN entries, so we're
|
|
// just starting up. A DERP map should arrive shortly
|
|
// and then we'll have more interesting endpoints to
|
|
// report. This saves a map update.
|
|
// TODO(bradfitz): this optimization is currently
|
|
// skipped during the e2e tests because they depend
|
|
// too much on the exact sequence of updates. Fix the
|
|
// tests. But a protocol rewrite might happen first.
|
|
c.logf("[v1] magicsock: ignoring pre-DERP map, STUN-less endpoint update: %v", endpoints)
|
|
return false
|
|
}
|
|
|
|
c.lastEndpointsTime = time.Now()
|
|
for de, fn := range c.onEndpointRefreshed {
|
|
go fn()
|
|
delete(c.onEndpointRefreshed, de)
|
|
}
|
|
|
|
if endpointSetsEqual(endpoints, c.lastEndpoints) {
|
|
return false
|
|
}
|
|
c.lastEndpoints = endpoints
|
|
return true
|
|
}
|
|
|
|
// setNetInfoHavePortMap updates NetInfo.HavePortMap to true.
|
|
func (c *Conn) setNetInfoHavePortMap() {
|
|
c.mu.Lock()
|
|
defer c.mu.Unlock()
|
|
if c.netInfoLast == nil {
|
|
// No NetInfo yet. Nothing to update.
|
|
return
|
|
}
|
|
if c.netInfoLast.HavePortMap {
|
|
// No change.
|
|
return
|
|
}
|
|
ni := c.netInfoLast.Clone()
|
|
ni.HavePortMap = true
|
|
c.callNetInfoCallbackLocked(ni)
|
|
}
|
|
|
|
func (c *Conn) updateNetInfo(ctx context.Context) (*netcheck.Report, error) {
|
|
c.mu.Lock()
|
|
dm := c.derpMap
|
|
c.mu.Unlock()
|
|
|
|
if dm == nil || c.networkDown() {
|
|
return new(netcheck.Report), nil
|
|
}
|
|
|
|
ctx, cancel := context.WithTimeout(ctx, 2*time.Second)
|
|
defer cancel()
|
|
|
|
c.stunReceiveFunc.Store(c.netChecker.ReceiveSTUNPacket)
|
|
defer c.ignoreSTUNPackets()
|
|
|
|
report, err := c.netChecker.GetReport(ctx, dm)
|
|
if err != nil {
|
|
return nil, err
|
|
}
|
|
|
|
c.noV4.Set(!report.IPv4)
|
|
c.noV6.Set(!report.IPv6)
|
|
c.noV4Send.Set(!report.IPv4CanSend)
|
|
|
|
ni := &tailcfg.NetInfo{
|
|
DERPLatency: map[string]float64{},
|
|
MappingVariesByDestIP: report.MappingVariesByDestIP,
|
|
HairPinning: report.HairPinning,
|
|
UPnP: report.UPnP,
|
|
PMP: report.PMP,
|
|
PCP: report.PCP,
|
|
HavePortMap: c.portMapper.HaveMapping(),
|
|
}
|
|
for rid, d := range report.RegionV4Latency {
|
|
ni.DERPLatency[fmt.Sprintf("%d-v4", rid)] = d.Seconds()
|
|
}
|
|
for rid, d := range report.RegionV6Latency {
|
|
ni.DERPLatency[fmt.Sprintf("%d-v6", rid)] = d.Seconds()
|
|
}
|
|
ni.WorkingIPv6.Set(report.IPv6)
|
|
ni.WorkingUDP.Set(report.UDP)
|
|
ni.PreferredDERP = report.PreferredDERP
|
|
|
|
if ni.PreferredDERP == 0 {
|
|
// Perhaps UDP is blocked. Pick a deterministic but arbitrary
|
|
// one.
|
|
ni.PreferredDERP = c.pickDERPFallback()
|
|
}
|
|
if !c.setNearestDERP(ni.PreferredDERP) {
|
|
ni.PreferredDERP = 0
|
|
}
|
|
|
|
// TODO: set link type
|
|
|
|
c.callNetInfoCallback(ni)
|
|
return report, nil
|
|
}
|
|
|
|
var processStartUnixNano = time.Now().UnixNano()
|
|
|
|
// pickDERPFallback returns a non-zero but deterministic DERP node to
|
|
// connect to. This is only used if netcheck couldn't find the
|
|
// nearest one (for instance, if UDP is blocked and thus STUN latency
|
|
// checks aren't working).
|
|
//
|
|
// c.mu must NOT be held.
|
|
func (c *Conn) pickDERPFallback() int {
|
|
c.mu.Lock()
|
|
defer c.mu.Unlock()
|
|
|
|
if !c.wantDerpLocked() {
|
|
return 0
|
|
}
|
|
ids := c.derpMap.RegionIDs()
|
|
if len(ids) == 0 {
|
|
// No DERP regions in non-nil map.
|
|
return 0
|
|
}
|
|
|
|
// TODO: figure out which DERP region most of our peers are using,
|
|
// and use that region as our fallback.
|
|
//
|
|
// If we already had selected something in the past and it has any
|
|
// peers, we want to stay on it. If there are no peers at all,
|
|
// stay on whatever DERP we previously picked. If we need to pick
|
|
// one and have no peer info, pick a region randomly.
|
|
//
|
|
// We used to do the above for legacy clients, but never updated
|
|
// it for disco.
|
|
|
|
if c.myDerp != 0 {
|
|
return c.myDerp
|
|
}
|
|
|
|
h := fnv.New64()
|
|
h.Write([]byte(fmt.Sprintf("%p/%d", c, processStartUnixNano))) // arbitrary
|
|
return ids[rand.New(rand.NewSource(int64(h.Sum64()))).Intn(len(ids))]
|
|
}
|
|
|
|
// callNetInfoCallback calls the NetInfo callback (if previously
|
|
// registered with SetNetInfoCallback) if ni has substantially changed
|
|
// since the last state.
|
|
//
|
|
// callNetInfoCallback takes ownership of ni.
|
|
//
|
|
// c.mu must NOT be held.
|
|
func (c *Conn) callNetInfoCallback(ni *tailcfg.NetInfo) {
|
|
c.mu.Lock()
|
|
defer c.mu.Unlock()
|
|
if ni.BasicallyEqual(c.netInfoLast) {
|
|
return
|
|
}
|
|
c.callNetInfoCallbackLocked(ni)
|
|
}
|
|
|
|
func (c *Conn) callNetInfoCallbackLocked(ni *tailcfg.NetInfo) {
|
|
c.netInfoLast = ni
|
|
if c.netInfoFunc != nil {
|
|
c.logf("[v1] magicsock: netInfo update: %+v", ni)
|
|
go c.netInfoFunc(ni)
|
|
}
|
|
}
|
|
|
|
// addValidDiscoPathForTest makes addr a validated disco address for
|
|
// discoKey. It's used in tests to enable receiving of packets from
|
|
// addr without having to spin up the entire active discovery
|
|
// machinery.
|
|
func (c *Conn) addValidDiscoPathForTest(nodeKey tailcfg.NodeKey, addr netaddr.IPPort) {
|
|
c.mu.Lock()
|
|
defer c.mu.Unlock()
|
|
c.peerMap.setNodeKeyForIPPort(addr, nodeKey)
|
|
}
|
|
|
|
func (c *Conn) SetNetInfoCallback(fn func(*tailcfg.NetInfo)) {
|
|
if fn == nil {
|
|
panic("nil NetInfoCallback")
|
|
}
|
|
c.mu.Lock()
|
|
last := c.netInfoLast
|
|
c.netInfoFunc = fn
|
|
c.mu.Unlock()
|
|
|
|
if last != nil {
|
|
fn(last)
|
|
}
|
|
}
|
|
|
|
// LastRecvActivityOfNodeKey describes the time we last got traffic from
|
|
// this endpoint (updated every ~10 seconds).
|
|
func (c *Conn) LastRecvActivityOfNodeKey(nk tailcfg.NodeKey) string {
|
|
c.mu.Lock()
|
|
defer c.mu.Unlock()
|
|
de, ok := c.peerMap.endpointForNodeKey(nk)
|
|
if !ok {
|
|
return "never"
|
|
}
|
|
saw := de.lastRecv.LoadAtomic()
|
|
if saw == 0 {
|
|
return "never"
|
|
}
|
|
return mono.Since(saw).Round(time.Second).String()
|
|
}
|
|
|
|
// Ping handles a "tailscale ping" CLI query.
|
|
func (c *Conn) Ping(peer *tailcfg.Node, res *ipnstate.PingResult, cb func(*ipnstate.PingResult)) {
|
|
c.mu.Lock()
|
|
defer c.mu.Unlock()
|
|
if c.privateKey.IsZero() {
|
|
res.Err = "local tailscaled stopped"
|
|
cb(res)
|
|
return
|
|
}
|
|
if len(peer.Addresses) > 0 {
|
|
res.NodeIP = peer.Addresses[0].IP().String()
|
|
}
|
|
res.NodeName = peer.Name // prefer DNS name
|
|
if res.NodeName == "" {
|
|
res.NodeName = peer.Hostinfo.Hostname // else hostname
|
|
} else {
|
|
if i := strings.Index(res.NodeName, "."); i != -1 {
|
|
res.NodeName = res.NodeName[:i]
|
|
}
|
|
}
|
|
|
|
ep, ok := c.peerMap.endpointForNodeKey(peer.Key)
|
|
if !ok {
|
|
res.Err = "unknown peer"
|
|
cb(res)
|
|
return
|
|
}
|
|
ep.cliPing(res, cb)
|
|
}
|
|
|
|
// c.mu must be held
|
|
func (c *Conn) populateCLIPingResponseLocked(res *ipnstate.PingResult, latency time.Duration, ep netaddr.IPPort) {
|
|
res.LatencySeconds = latency.Seconds()
|
|
if ep.IP() != derpMagicIPAddr {
|
|
res.Endpoint = ep.String()
|
|
return
|
|
}
|
|
regionID := int(ep.Port())
|
|
res.DERPRegionID = regionID
|
|
res.DERPRegionCode = c.derpRegionCodeLocked(regionID)
|
|
}
|
|
|
|
func (c *Conn) derpRegionCodeLocked(regionID int) string {
|
|
if c.derpMap == nil {
|
|
return ""
|
|
}
|
|
if dr, ok := c.derpMap.Regions[regionID]; ok {
|
|
return dr.RegionCode
|
|
}
|
|
return ""
|
|
}
|
|
|
|
// DiscoPublicKey returns the discovery public key.
|
|
func (c *Conn) DiscoPublicKey() tailcfg.DiscoKey {
|
|
c.mu.Lock()
|
|
defer c.mu.Unlock()
|
|
if c.discoPrivate.IsZero() {
|
|
priv := key.NewPrivate()
|
|
c.discoPrivate = priv
|
|
c.discoPublic = tailcfg.DiscoKey(priv.Public())
|
|
c.discoShort = c.discoPublic.ShortString()
|
|
c.logf("magicsock: disco key = %v", c.discoShort)
|
|
}
|
|
return c.discoPublic
|
|
}
|
|
|
|
// PeerHasDiscoKey reports whether peer k supports discovery keys (client version 0.100.0+).
|
|
func (c *Conn) PeerHasDiscoKey(k tailcfg.NodeKey) bool {
|
|
c.mu.Lock()
|
|
defer c.mu.Unlock()
|
|
if ep, ok := c.peerMap.endpointForNodeKey(k); ok {
|
|
return ep.discoKey.IsZero()
|
|
}
|
|
return false
|
|
}
|
|
|
|
// c.mu must NOT be held.
|
|
func (c *Conn) setNearestDERP(derpNum int) (wantDERP bool) {
|
|
c.mu.Lock()
|
|
defer c.mu.Unlock()
|
|
if !c.wantDerpLocked() {
|
|
c.myDerp = 0
|
|
health.SetMagicSockDERPHome(0)
|
|
return false
|
|
}
|
|
if derpNum == c.myDerp {
|
|
// No change.
|
|
return true
|
|
}
|
|
c.myDerp = derpNum
|
|
health.SetMagicSockDERPHome(derpNum)
|
|
|
|
if c.privateKey.IsZero() {
|
|
// No private key yet, so DERP connections won't come up anyway.
|
|
// Return early rather than ultimately log a couple lines of noise.
|
|
return true
|
|
}
|
|
|
|
// On change, notify all currently connected DERP servers and
|
|
// start connecting to our home DERP if we are not already.
|
|
dr := c.derpMap.Regions[derpNum]
|
|
if dr == nil {
|
|
c.logf("[unexpected] magicsock: derpMap.Regions[%v] is nil", derpNum)
|
|
} else {
|
|
c.logf("magicsock: home is now derp-%v (%v)", derpNum, c.derpMap.Regions[derpNum].RegionCode)
|
|
}
|
|
for i, ad := range c.activeDerp {
|
|
go ad.c.NotePreferred(i == c.myDerp)
|
|
}
|
|
c.goDerpConnect(derpNum)
|
|
return true
|
|
}
|
|
|
|
// startDerpHomeConnectLocked starts connecting to our DERP home, if any.
|
|
//
|
|
// c.mu must be held.
|
|
func (c *Conn) startDerpHomeConnectLocked() {
|
|
c.goDerpConnect(c.myDerp)
|
|
}
|
|
|
|
// goDerpConnect starts a goroutine to start connecting to the given
|
|
// DERP node.
|
|
//
|
|
// c.mu may be held, but does not need to be.
|
|
func (c *Conn) goDerpConnect(node int) {
|
|
if node == 0 {
|
|
return
|
|
}
|
|
go c.derpWriteChanOfAddr(netaddr.IPPortFrom(derpMagicIPAddr, uint16(node)), key.NodePublic{})
|
|
}
|
|
|
|
// determineEndpoints returns the machine's endpoint addresses. It
|
|
// does a STUN lookup (via netcheck) to determine its public address.
|
|
//
|
|
// c.mu must NOT be held.
|
|
func (c *Conn) determineEndpoints(ctx context.Context) ([]tailcfg.Endpoint, error) {
|
|
var havePortmap bool
|
|
var portmapExt netaddr.IPPort
|
|
if runtime.GOOS != "js" {
|
|
portmapExt, havePortmap = c.portMapper.GetCachedMappingOrStartCreatingOne()
|
|
}
|
|
|
|
nr, err := c.updateNetInfo(ctx)
|
|
if err != nil {
|
|
c.logf("magicsock.Conn.determineEndpoints: updateNetInfo: %v", err)
|
|
return nil, err
|
|
}
|
|
|
|
if runtime.GOOS == "js" {
|
|
// TODO(bradfitz): why does control require an
|
|
// endpoint? Otherwise it doesn't stream map responses
|
|
// back.
|
|
return []tailcfg.Endpoint{
|
|
{
|
|
Addr: netaddr.MustParseIPPort("[fe80:123:456:789::1]:12345"),
|
|
Type: tailcfg.EndpointLocal,
|
|
},
|
|
}, nil
|
|
}
|
|
|
|
already := make(map[netaddr.IPPort]tailcfg.EndpointType) // endpoint -> how it was found
|
|
var eps []tailcfg.Endpoint // unique endpoints
|
|
|
|
ipp := func(s string) (ipp netaddr.IPPort) {
|
|
ipp, _ = netaddr.ParseIPPort(s)
|
|
return
|
|
}
|
|
addAddr := func(ipp netaddr.IPPort, et tailcfg.EndpointType) {
|
|
if ipp.IsZero() || (debugOmitLocalAddresses && et == tailcfg.EndpointLocal) {
|
|
return
|
|
}
|
|
if _, ok := already[ipp]; !ok {
|
|
already[ipp] = et
|
|
eps = append(eps, tailcfg.Endpoint{Addr: ipp, Type: et})
|
|
}
|
|
}
|
|
|
|
// If we didn't have a portmap earlier, maybe it's done by now.
|
|
if !havePortmap {
|
|
portmapExt, havePortmap = c.portMapper.GetCachedMappingOrStartCreatingOne()
|
|
}
|
|
if havePortmap {
|
|
addAddr(portmapExt, tailcfg.EndpointPortmapped)
|
|
c.setNetInfoHavePortMap()
|
|
}
|
|
|
|
if nr.GlobalV4 != "" {
|
|
addAddr(ipp(nr.GlobalV4), tailcfg.EndpointSTUN)
|
|
|
|
// If they're behind a hard NAT and are using a fixed
|
|
// port locally, assume they might've added a static
|
|
// port mapping on their router to the same explicit
|
|
// port that tailscaled is running with. Worst case
|
|
// it's an invalid candidate mapping.
|
|
if port := c.port.Get(); nr.MappingVariesByDestIP.EqualBool(true) && port != 0 {
|
|
if ip, _, err := net.SplitHostPort(nr.GlobalV4); err == nil {
|
|
addAddr(ipp(net.JoinHostPort(ip, strconv.Itoa(int(port)))), tailcfg.EndpointSTUN4LocalPort)
|
|
}
|
|
}
|
|
}
|
|
if nr.GlobalV6 != "" {
|
|
addAddr(ipp(nr.GlobalV6), tailcfg.EndpointSTUN)
|
|
}
|
|
|
|
c.ignoreSTUNPackets()
|
|
|
|
if localAddr := c.pconn4.LocalAddr(); localAddr.IP.IsUnspecified() {
|
|
ips, loopback, err := interfaces.LocalAddresses()
|
|
if err != nil {
|
|
return nil, err
|
|
}
|
|
if len(ips) == 0 && len(eps) == 0 {
|
|
// Only include loopback addresses if we have no
|
|
// interfaces at all to use as endpoints and don't
|
|
// have a public IPv4 or IPv6 address. This allows
|
|
// for localhost testing when you're on a plane and
|
|
// offline, for example.
|
|
ips = loopback
|
|
}
|
|
for _, ip := range ips {
|
|
addAddr(netaddr.IPPortFrom(ip, uint16(localAddr.Port)), tailcfg.EndpointLocal)
|
|
}
|
|
} else {
|
|
// Our local endpoint is bound to a particular address.
|
|
// Do not offer addresses on other local interfaces.
|
|
addAddr(ipp(localAddr.String()), tailcfg.EndpointLocal)
|
|
}
|
|
|
|
// Note: the endpoints are intentionally returned in priority order,
|
|
// from "farthest but most reliable" to "closest but least
|
|
// reliable." Addresses returned from STUN should be globally
|
|
// addressable, but might go farther on the network than necessary.
|
|
// Local interface addresses might have lower latency, but not be
|
|
// globally addressable.
|
|
//
|
|
// The STUN address(es) are always first so that legacy wireguard
|
|
// can use eps[0] as its only known endpoint address (although that's
|
|
// obviously non-ideal).
|
|
//
|
|
// Despite this sorting, though, clients since 0.100 haven't relied
|
|
// on the sorting order for any decisions.
|
|
return eps, nil
|
|
}
|
|
|
|
// endpointSetsEqual reports whether x and y represent the same set of
|
|
// endpoints. The order doesn't matter.
|
|
//
|
|
// It does not mutate the slices.
|
|
func endpointSetsEqual(x, y []tailcfg.Endpoint) bool {
|
|
if len(x) == len(y) {
|
|
orderMatches := true
|
|
for i := range x {
|
|
if x[i] != y[i] {
|
|
orderMatches = false
|
|
break
|
|
}
|
|
}
|
|
if orderMatches {
|
|
return true
|
|
}
|
|
}
|
|
m := map[tailcfg.Endpoint]int{}
|
|
for _, v := range x {
|
|
m[v] |= 1
|
|
}
|
|
for _, v := range y {
|
|
m[v] |= 2
|
|
}
|
|
for _, n := range m {
|
|
if n != 3 {
|
|
return false
|
|
}
|
|
}
|
|
return true
|
|
}
|
|
|
|
// LocalPort returns the current IPv4 listener's port number.
|
|
func (c *Conn) LocalPort() uint16 {
|
|
if runtime.GOOS == "js" {
|
|
return 12345
|
|
}
|
|
laddr := c.pconn4.LocalAddr()
|
|
return uint16(laddr.Port)
|
|
}
|
|
|
|
var errNetworkDown = errors.New("magicsock: network down")
|
|
|
|
func (c *Conn) networkDown() bool { return !c.networkUp.Get() }
|
|
|
|
func (c *Conn) Send(b []byte, ep conn.Endpoint) error {
|
|
if c.networkDown() {
|
|
return errNetworkDown
|
|
}
|
|
return ep.(*endpoint).send(b)
|
|
}
|
|
|
|
var errConnClosed = errors.New("Conn closed")
|
|
|
|
var errDropDerpPacket = errors.New("too many DERP packets queued; dropping")
|
|
|
|
var errNoUDP = errors.New("no UDP available on platform")
|
|
|
|
var udpAddrPool = &sync.Pool{
|
|
New: func() interface{} { return new(net.UDPAddr) },
|
|
}
|
|
|
|
// sendUDP sends UDP packet b to ipp.
|
|
// See sendAddr's docs on the return value meanings.
|
|
func (c *Conn) sendUDP(ipp netaddr.IPPort, b []byte) (sent bool, err error) {
|
|
if runtime.GOOS == "js" {
|
|
return false, errNoUDP
|
|
}
|
|
ua := udpAddrPool.Get().(*net.UDPAddr)
|
|
sent, err = c.sendUDPStd(ipp.UDPAddrAt(ua), b)
|
|
if err == nil {
|
|
// Only return it to the pool on success; Issue 3122.
|
|
udpAddrPool.Put(ua)
|
|
}
|
|
return
|
|
}
|
|
|
|
// sendUDP sends UDP packet b to addr.
|
|
// See sendAddr's docs on the return value meanings.
|
|
func (c *Conn) sendUDPStd(addr *net.UDPAddr, b []byte) (sent bool, err error) {
|
|
switch {
|
|
case addr.IP.To4() != nil:
|
|
_, err = c.pconn4.WriteTo(b, addr)
|
|
if err != nil && c.noV4.Get() {
|
|
return false, nil
|
|
}
|
|
case len(addr.IP) == net.IPv6len:
|
|
if c.pconn6 == nil {
|
|
// ignore IPv6 dest if we don't have an IPv6 address.
|
|
return false, nil
|
|
}
|
|
_, err = c.pconn6.WriteTo(b, addr)
|
|
if err != nil && c.noV6.Get() {
|
|
return false, nil
|
|
}
|
|
default:
|
|
panic("bogus sendUDPStd addr type")
|
|
}
|
|
return err == nil, err
|
|
}
|
|
|
|
// sendAddr sends packet b to addr, which is either a real UDP address
|
|
// or a fake UDP address representing a DERP server (see derpmap.go).
|
|
// The provided public key identifies the recipient.
|
|
//
|
|
// The returned err is whether there was an error writing when it
|
|
// should've worked.
|
|
// The returned sent is whether a packet went out at all.
|
|
// An example of when they might be different: sending to an
|
|
// IPv6 address when the local machine doesn't have IPv6 support
|
|
// returns (false, nil); it's not an error, but nothing was sent.
|
|
func (c *Conn) sendAddr(addr netaddr.IPPort, pubKey key.NodePublic, b []byte) (sent bool, err error) {
|
|
if addr.IP() != derpMagicIPAddr {
|
|
return c.sendUDP(addr, b)
|
|
}
|
|
|
|
ch := c.derpWriteChanOfAddr(addr, pubKey)
|
|
if ch == nil {
|
|
return false, nil
|
|
}
|
|
|
|
// TODO(bradfitz): this makes garbage for now; we could use a
|
|
// buffer pool later. Previously we passed ownership of this
|
|
// to derpWriteRequest and waited for derphttp.Client.Send to
|
|
// complete, but that's too slow while holding wireguard-go
|
|
// internal locks.
|
|
pkt := make([]byte, len(b))
|
|
copy(pkt, b)
|
|
|
|
select {
|
|
case <-c.donec:
|
|
return false, errConnClosed
|
|
case ch <- derpWriteRequest{addr, pubKey, pkt}:
|
|
return true, nil
|
|
default:
|
|
// Too many writes queued. Drop packet.
|
|
return false, errDropDerpPacket
|
|
}
|
|
}
|
|
|
|
// bufferedDerpWritesBeforeDrop is how many packets writes can be
|
|
// queued up the DERP client to write on the wire before we start
|
|
// dropping.
|
|
//
|
|
// TODO: this is currently arbitrary. Figure out something better?
|
|
const bufferedDerpWritesBeforeDrop = 32
|
|
|
|
// derpWriteChanOfAddr returns a DERP client for fake UDP addresses that
|
|
// represent DERP servers, creating them as necessary. For real UDP
|
|
// addresses, it returns nil.
|
|
//
|
|
// If peer is non-zero, it can be used to find an active reverse
|
|
// path, without using addr.
|
|
func (c *Conn) derpWriteChanOfAddr(addr netaddr.IPPort, peer key.NodePublic) chan<- derpWriteRequest {
|
|
if addr.IP() != derpMagicIPAddr {
|
|
return nil
|
|
}
|
|
regionID := int(addr.Port())
|
|
|
|
if c.networkDown() {
|
|
return nil
|
|
}
|
|
|
|
c.mu.Lock()
|
|
defer c.mu.Unlock()
|
|
if !c.wantDerpLocked() || c.closed {
|
|
return nil
|
|
}
|
|
if c.privateKey.IsZero() {
|
|
c.logf("magicsock: DERP lookup of %v with no private key; ignoring", addr)
|
|
return nil
|
|
}
|
|
|
|
// See if we have a connection open to that DERP node ID
|
|
// first. If so, might as well use it. (It's a little
|
|
// arbitrary whether we use this one vs. the reverse route
|
|
// below when we have both.)
|
|
ad, ok := c.activeDerp[regionID]
|
|
if ok {
|
|
*ad.lastWrite = time.Now()
|
|
c.setPeerLastDerpLocked(peer, regionID, regionID)
|
|
return ad.writeCh
|
|
}
|
|
|
|
// If we don't have an open connection to the peer's home DERP
|
|
// node, see if we have an open connection to a DERP node
|
|
// where we'd heard from that peer already. For instance,
|
|
// perhaps peer's home is Frankfurt, but they dialed our home DERP
|
|
// node in SF to reach us, so we can reply to them using our
|
|
// SF connection rather than dialing Frankfurt. (Issue 150)
|
|
if !peer.IsZero() && useDerpRoute() {
|
|
if r, ok := c.derpRoute[peer]; ok {
|
|
if ad, ok := c.activeDerp[r.derpID]; ok && ad.c == r.dc {
|
|
c.setPeerLastDerpLocked(peer, r.derpID, regionID)
|
|
*ad.lastWrite = time.Now()
|
|
return ad.writeCh
|
|
}
|
|
}
|
|
}
|
|
|
|
why := "home-keep-alive"
|
|
if !peer.IsZero() {
|
|
why = peer.ShortString()
|
|
}
|
|
c.logf("magicsock: adding connection to derp-%v for %v", regionID, why)
|
|
|
|
firstDerp := false
|
|
if c.activeDerp == nil {
|
|
firstDerp = true
|
|
c.activeDerp = make(map[int]activeDerp)
|
|
c.prevDerp = make(map[int]*syncs.WaitGroupChan)
|
|
}
|
|
if c.derpMap == nil || c.derpMap.Regions[regionID] == nil {
|
|
return nil
|
|
}
|
|
|
|
// Note that derphttp.NewRegionClient does not dial the server
|
|
// so it is safe to do under the mu lock.
|
|
dc := derphttp.NewRegionClient(c.privateKey, c.logf, func() *tailcfg.DERPRegion {
|
|
if c.connCtx.Err() != nil {
|
|
// If we're closing, don't try to acquire the lock.
|
|
// We might already be in Conn.Close and the Lock would deadlock.
|
|
return nil
|
|
}
|
|
c.mu.Lock()
|
|
defer c.mu.Unlock()
|
|
if c.derpMap == nil {
|
|
return nil
|
|
}
|
|
return c.derpMap.Regions[regionID]
|
|
})
|
|
|
|
dc.SetCanAckPings(true)
|
|
dc.NotePreferred(c.myDerp == regionID)
|
|
dc.DNSCache = dnscache.Get()
|
|
|
|
ctx, cancel := context.WithCancel(c.connCtx)
|
|
ch := make(chan derpWriteRequest, bufferedDerpWritesBeforeDrop)
|
|
|
|
ad.c = dc
|
|
ad.writeCh = ch
|
|
ad.cancel = cancel
|
|
ad.lastWrite = new(time.Time)
|
|
*ad.lastWrite = time.Now()
|
|
ad.createTime = time.Now()
|
|
c.activeDerp[regionID] = ad
|
|
c.logActiveDerpLocked()
|
|
c.setPeerLastDerpLocked(peer, regionID, regionID)
|
|
c.scheduleCleanStaleDerpLocked()
|
|
|
|
// Build a startGate for the derp reader+writer
|
|
// goroutines, so they don't start running until any
|
|
// previous generation is closed.
|
|
startGate := syncs.ClosedChan()
|
|
if prev := c.prevDerp[regionID]; prev != nil {
|
|
startGate = prev.DoneChan()
|
|
}
|
|
// And register a WaitGroup(Chan) for this generation.
|
|
wg := syncs.NewWaitGroupChan()
|
|
wg.Add(2)
|
|
c.prevDerp[regionID] = wg
|
|
|
|
if firstDerp {
|
|
startGate = c.derpStarted
|
|
go func() {
|
|
dc.Connect(ctx)
|
|
close(c.derpStarted)
|
|
c.muCond.Broadcast()
|
|
}()
|
|
}
|
|
|
|
go c.runDerpReader(ctx, addr, dc, wg, startGate)
|
|
go c.runDerpWriter(ctx, dc, ch, wg, startGate)
|
|
go c.derpActiveFunc()
|
|
|
|
return ad.writeCh
|
|
}
|
|
|
|
// setPeerLastDerpLocked notes that peer is now being written to via
|
|
// the provided DERP regionID, and that the peer advertises a DERP
|
|
// home region ID of homeID.
|
|
//
|
|
// If there's any change, it logs.
|
|
//
|
|
// c.mu must be held.
|
|
func (c *Conn) setPeerLastDerpLocked(peer key.NodePublic, regionID, homeID int) {
|
|
if peer.IsZero() {
|
|
return
|
|
}
|
|
old := c.peerLastDerp[peer]
|
|
if old == regionID {
|
|
return
|
|
}
|
|
c.peerLastDerp[peer] = regionID
|
|
|
|
var newDesc string
|
|
switch {
|
|
case regionID == homeID && regionID == c.myDerp:
|
|
newDesc = "shared home"
|
|
case regionID == homeID:
|
|
newDesc = "their home"
|
|
case regionID == c.myDerp:
|
|
newDesc = "our home"
|
|
case regionID != homeID:
|
|
newDesc = "alt"
|
|
}
|
|
if old == 0 {
|
|
c.logf("[v1] magicsock: derp route for %s set to derp-%d (%s)", peer.ShortString(), regionID, newDesc)
|
|
} else {
|
|
c.logf("[v1] magicsock: derp route for %s changed from derp-%d => derp-%d (%s)", peer.ShortString(), old, regionID, newDesc)
|
|
}
|
|
}
|
|
|
|
// derpReadResult is the type sent by runDerpClient to ReceiveIPv4
|
|
// when a DERP packet is available.
|
|
//
|
|
// Notably, it doesn't include the derp.ReceivedPacket because we
|
|
// don't want to give the receiver access to the aliased []byte. To
|
|
// get at the packet contents they need to call copyBuf to copy it
|
|
// out, which also releases the buffer.
|
|
type derpReadResult struct {
|
|
regionID int
|
|
n int // length of data received
|
|
src key.NodePublic
|
|
// copyBuf is called to copy the data to dst. It returns how
|
|
// much data was copied, which will be n if dst is large
|
|
// enough. copyBuf can only be called once.
|
|
// If copyBuf is nil, that's a signal from the sender to ignore
|
|
// this message.
|
|
copyBuf func(dst []byte) int
|
|
}
|
|
|
|
// runDerpReader runs in a goroutine for the life of a DERP
|
|
// connection, handling received packets.
|
|
func (c *Conn) runDerpReader(ctx context.Context, derpFakeAddr netaddr.IPPort, dc *derphttp.Client, wg *syncs.WaitGroupChan, startGate <-chan struct{}) {
|
|
defer wg.Decr()
|
|
defer dc.Close()
|
|
|
|
select {
|
|
case <-startGate:
|
|
case <-ctx.Done():
|
|
return
|
|
}
|
|
|
|
didCopy := make(chan struct{}, 1)
|
|
regionID := int(derpFakeAddr.Port())
|
|
res := derpReadResult{regionID: regionID}
|
|
var pkt derp.ReceivedPacket
|
|
res.copyBuf = func(dst []byte) int {
|
|
n := copy(dst, pkt.Data)
|
|
didCopy <- struct{}{}
|
|
return n
|
|
}
|
|
|
|
defer health.SetDERPRegionConnectedState(regionID, false)
|
|
defer health.SetDERPRegionHealth(regionID, "")
|
|
|
|
// peerPresent is the set of senders we know are present on this
|
|
// connection, based on messages we've received from the server.
|
|
peerPresent := map[key.NodePublic]bool{}
|
|
bo := backoff.NewBackoff(fmt.Sprintf("derp-%d", regionID), c.logf, 5*time.Second)
|
|
var lastPacketTime time.Time
|
|
|
|
for {
|
|
msg, connGen, err := dc.RecvDetail()
|
|
if err != nil {
|
|
health.SetDERPRegionConnectedState(regionID, false)
|
|
// Forget that all these peers have routes.
|
|
for peer := range peerPresent {
|
|
delete(peerPresent, peer)
|
|
c.removeDerpPeerRoute(peer, regionID, dc)
|
|
}
|
|
if err == derphttp.ErrClientClosed {
|
|
return
|
|
}
|
|
if c.networkDown() {
|
|
c.logf("[v1] magicsock: derp.Recv(derp-%d): network down, closing", regionID)
|
|
return
|
|
}
|
|
select {
|
|
case <-ctx.Done():
|
|
return
|
|
default:
|
|
}
|
|
|
|
c.logf("magicsock: [%p] derp.Recv(derp-%d): %v", dc, regionID, err)
|
|
|
|
// If our DERP connection broke, it might be because our network
|
|
// conditions changed. Start that check.
|
|
c.ReSTUN("derp-recv-error")
|
|
|
|
// Back off a bit before reconnecting.
|
|
bo.BackOff(ctx, err)
|
|
select {
|
|
case <-ctx.Done():
|
|
return
|
|
default:
|
|
}
|
|
continue
|
|
}
|
|
bo.BackOff(ctx, nil) // reset
|
|
|
|
now := time.Now()
|
|
if lastPacketTime.IsZero() || now.Sub(lastPacketTime) > 5*time.Second {
|
|
health.NoteDERPRegionReceivedFrame(regionID)
|
|
lastPacketTime = now
|
|
}
|
|
|
|
switch m := msg.(type) {
|
|
case derp.ServerInfoMessage:
|
|
health.SetDERPRegionConnectedState(regionID, true)
|
|
health.SetDERPRegionHealth(regionID, "") // until declared otherwise
|
|
c.logf("magicsock: derp-%d connected; connGen=%v", regionID, connGen)
|
|
continue
|
|
case derp.ReceivedPacket:
|
|
pkt = m
|
|
res.n = len(m.Data)
|
|
res.src = m.Source
|
|
if logDerpVerbose {
|
|
c.logf("magicsock: got derp-%v packet: %q", regionID, m.Data)
|
|
}
|
|
// If this is a new sender we hadn't seen before, remember it and
|
|
// register a route for this peer.
|
|
if _, ok := peerPresent[res.src]; !ok {
|
|
peerPresent[res.src] = true
|
|
c.addDerpPeerRoute(res.src, regionID, dc)
|
|
}
|
|
case derp.PingMessage:
|
|
// Best effort reply to the ping.
|
|
pingData := [8]byte(m)
|
|
go func() {
|
|
if err := dc.SendPong(pingData); err != nil {
|
|
c.logf("magicsock: derp-%d SendPong error: %v", regionID, err)
|
|
}
|
|
}()
|
|
continue
|
|
case derp.HealthMessage:
|
|
health.SetDERPRegionHealth(regionID, m.Problem)
|
|
default:
|
|
// Ignore.
|
|
continue
|
|
}
|
|
|
|
select {
|
|
case <-ctx.Done():
|
|
return
|
|
case c.derpRecvCh <- res:
|
|
}
|
|
|
|
select {
|
|
case <-ctx.Done():
|
|
return
|
|
case <-didCopy:
|
|
continue
|
|
}
|
|
}
|
|
}
|
|
|
|
type derpWriteRequest struct {
|
|
addr netaddr.IPPort
|
|
pubKey key.NodePublic
|
|
b []byte // copied; ownership passed to receiver
|
|
}
|
|
|
|
// runDerpWriter runs in a goroutine for the life of a DERP
|
|
// connection, handling received packets.
|
|
func (c *Conn) runDerpWriter(ctx context.Context, dc *derphttp.Client, ch <-chan derpWriteRequest, wg *syncs.WaitGroupChan, startGate <-chan struct{}) {
|
|
defer wg.Decr()
|
|
select {
|
|
case <-startGate:
|
|
case <-ctx.Done():
|
|
return
|
|
}
|
|
|
|
for {
|
|
select {
|
|
case <-ctx.Done():
|
|
return
|
|
case wr := <-ch:
|
|
err := dc.Send(wr.pubKey, wr.b)
|
|
if err != nil {
|
|
c.logf("magicsock: derp.Send(%v): %v", wr.addr, err)
|
|
}
|
|
}
|
|
}
|
|
}
|
|
|
|
// receiveIPv6 receives a UDP IPv6 packet. It is called by wireguard-go.
|
|
func (c *Conn) receiveIPv6(b []byte) (int, conn.Endpoint, error) {
|
|
health.ReceiveIPv6.Enter()
|
|
defer health.ReceiveIPv6.Exit()
|
|
for {
|
|
n, ipp, err := c.pconn6.ReadFromNetaddr(b)
|
|
if err != nil {
|
|
return 0, nil, err
|
|
}
|
|
if ep, ok := c.receiveIP(b[:n], ipp, &c.ippEndpoint6); ok {
|
|
return n, ep, nil
|
|
}
|
|
}
|
|
}
|
|
|
|
// receiveIPv4 receives a UDP IPv4 packet. It is called by wireguard-go.
|
|
func (c *Conn) receiveIPv4(b []byte) (n int, ep conn.Endpoint, err error) {
|
|
health.ReceiveIPv4.Enter()
|
|
defer health.ReceiveIPv4.Exit()
|
|
for {
|
|
n, ipp, err := c.pconn4.ReadFromNetaddr(b)
|
|
if err != nil {
|
|
return 0, nil, err
|
|
}
|
|
if ep, ok := c.receiveIP(b[:n], ipp, &c.ippEndpoint4); ok {
|
|
return n, ep, nil
|
|
}
|
|
}
|
|
}
|
|
|
|
// receiveIP is the shared bits of ReceiveIPv4 and ReceiveIPv6.
|
|
//
|
|
// ok is whether this read should be reported up to wireguard-go (our
|
|
// caller).
|
|
func (c *Conn) receiveIP(b []byte, ipp netaddr.IPPort, cache *ippEndpointCache) (ep *endpoint, ok bool) {
|
|
if stun.Is(b) {
|
|
c.stunReceiveFunc.Load().(func([]byte, netaddr.IPPort))(b, ipp)
|
|
return nil, false
|
|
}
|
|
if c.handleDiscoMessage(b, ipp, tailcfg.NodeKey{}) {
|
|
return nil, false
|
|
}
|
|
if !c.havePrivateKey.Get() {
|
|
// If we have no private key, we're logged out or
|
|
// stopped. Don't try to pass these wireguard packets
|
|
// up to wireguard-go; it'll just complain (issue 1167).
|
|
return nil, false
|
|
}
|
|
if cache.ipp == ipp && cache.de != nil && cache.gen == cache.de.numStopAndReset() {
|
|
ep = cache.de
|
|
} else {
|
|
c.mu.Lock()
|
|
de, ok := c.peerMap.endpointForIPPort(ipp)
|
|
c.mu.Unlock()
|
|
if !ok {
|
|
return nil, false
|
|
}
|
|
cache.ipp = ipp
|
|
cache.de = de
|
|
cache.gen = de.numStopAndReset()
|
|
ep = de
|
|
}
|
|
ep.noteRecvActivity()
|
|
return ep, true
|
|
}
|
|
|
|
// receiveDERP reads a packet from c.derpRecvCh into b and returns the associated endpoint.
|
|
// It is called by wireguard-go.
|
|
//
|
|
// If the packet was a disco message or the peer endpoint wasn't
|
|
// found, the returned error is errLoopAgain.
|
|
func (c *connBind) receiveDERP(b []byte) (n int, ep conn.Endpoint, err error) {
|
|
health.ReceiveDERP.Enter()
|
|
defer health.ReceiveDERP.Exit()
|
|
for dm := range c.derpRecvCh {
|
|
if c.Closed() {
|
|
break
|
|
}
|
|
n, ep := c.processDERPReadResult(dm, b)
|
|
if n == 0 {
|
|
// No data read occurred. Wait for another packet.
|
|
continue
|
|
}
|
|
return n, ep, nil
|
|
}
|
|
return 0, nil, net.ErrClosed
|
|
}
|
|
|
|
func (c *Conn) processDERPReadResult(dm derpReadResult, b []byte) (n int, ep *endpoint) {
|
|
if dm.copyBuf == nil {
|
|
return 0, nil
|
|
}
|
|
var regionID int
|
|
n, regionID = dm.n, dm.regionID
|
|
ncopy := dm.copyBuf(b)
|
|
if ncopy != n {
|
|
err := fmt.Errorf("received DERP packet of length %d that's too big for WireGuard buf size %d", n, ncopy)
|
|
c.logf("magicsock: %v", err)
|
|
return 0, nil
|
|
}
|
|
|
|
ipp := netaddr.IPPortFrom(derpMagicIPAddr, uint16(regionID))
|
|
if c.handleDiscoMessage(b[:n], ipp, tailcfg.NodeKeyFromNodePublic(dm.src)) {
|
|
return 0, nil
|
|
}
|
|
|
|
var ok bool
|
|
c.mu.Lock()
|
|
ep, ok = c.peerMap.endpointForNodeKey(tailcfg.NodeKeyFromNodePublic(dm.src))
|
|
c.mu.Unlock()
|
|
if !ok {
|
|
// We don't know anything about this node key, nothing to
|
|
// record or process.
|
|
return 0, nil
|
|
}
|
|
|
|
ep.noteRecvActivity()
|
|
return n, ep
|
|
}
|
|
|
|
// discoLogLevel controls the verbosity of discovery log messages.
|
|
type discoLogLevel int
|
|
|
|
const (
|
|
// discoLog means that a message should be logged.
|
|
discoLog discoLogLevel = iota
|
|
|
|
// discoVerboseLog means that a message should only be logged
|
|
// in TS_DEBUG_DISCO mode.
|
|
discoVerboseLog
|
|
)
|
|
|
|
// sendDiscoMessage sends discovery message m to dstDisco at dst.
|
|
//
|
|
// If dst is a DERP IP:port, then dstKey must be non-zero.
|
|
//
|
|
// The dstKey should only be non-zero if the dstDisco key
|
|
// unambiguously maps to exactly one peer.
|
|
func (c *Conn) sendDiscoMessage(dst netaddr.IPPort, dstKey tailcfg.NodeKey, dstDisco tailcfg.DiscoKey, m disco.Message, logLevel discoLogLevel) (sent bool, err error) {
|
|
c.mu.Lock()
|
|
if c.closed {
|
|
c.mu.Unlock()
|
|
return false, errConnClosed
|
|
}
|
|
var nonce [disco.NonceLen]byte
|
|
if _, err := crand.Read(nonce[:]); err != nil {
|
|
panic(err) // worth dying for
|
|
}
|
|
pkt := make([]byte, 0, 512) // TODO: size it correctly? pool? if it matters.
|
|
pkt = append(pkt, disco.Magic...)
|
|
pkt = append(pkt, c.discoPublic[:]...)
|
|
pkt = append(pkt, nonce[:]...)
|
|
di := c.discoInfoLocked(dstDisco)
|
|
c.mu.Unlock()
|
|
|
|
pkt = box.SealAfterPrecomputation(pkt, m.AppendMarshal(nil), &nonce, di.sharedKey)
|
|
sent, err = c.sendAddr(dst, key.NodePublicFromRaw32(mem.B(dstKey[:])), pkt)
|
|
if sent {
|
|
if logLevel == discoLog || (logLevel == discoVerboseLog && debugDisco) {
|
|
node := "?"
|
|
if !dstKey.IsZero() {
|
|
node = dstKey.ShortString()
|
|
}
|
|
c.logf("[v1] magicsock: disco: %v->%v (%v, %v) sent %v", c.discoShort, dstDisco.ShortString(), node, derpStr(dst.String()), disco.MessageSummary(m))
|
|
}
|
|
} else if err == nil {
|
|
// Can't send. (e.g. no IPv6 locally)
|
|
} else {
|
|
if !c.networkDown() {
|
|
c.logf("magicsock: disco: failed to send %T to %v: %v", m, dst, err)
|
|
}
|
|
}
|
|
return sent, err
|
|
}
|
|
|
|
// handleDiscoMessage handles a discovery message and reports whether
|
|
// msg was a Tailscale inter-node discovery message.
|
|
//
|
|
// A discovery message has the form:
|
|
//
|
|
// * magic [6]byte
|
|
// * senderDiscoPubKey [32]byte
|
|
// * nonce [24]byte
|
|
// * naclbox of payload (see tailscale.com/disco package for inner payload format)
|
|
//
|
|
// For messages received over DERP, the src.IP() will be derpMagicIP (with
|
|
// src.Port() being the region ID) and the derpNodeSrc will be the node key
|
|
// it was received from at the DERP layer. derpNodeSrc is zero when received
|
|
// over UDP.
|
|
func (c *Conn) handleDiscoMessage(msg []byte, src netaddr.IPPort, derpNodeSrc tailcfg.NodeKey) (isDiscoMsg bool) {
|
|
const headerLen = len(disco.Magic) + len(tailcfg.DiscoKey{}) + disco.NonceLen
|
|
if len(msg) < headerLen || string(msg[:len(disco.Magic)]) != disco.Magic {
|
|
return false
|
|
}
|
|
|
|
// If the first four parts are the prefix of disco.Magic
|
|
// (0x5453f09f) then it's definitely not a valid Wireguard
|
|
// packet (which starts with little-endian uint32 1, 2, 3, 4).
|
|
// Use naked returns for all following paths.
|
|
isDiscoMsg = true
|
|
|
|
var sender tailcfg.DiscoKey
|
|
copy(sender[:], msg[len(disco.Magic):])
|
|
|
|
c.mu.Lock()
|
|
defer c.mu.Unlock()
|
|
|
|
if c.closed {
|
|
return
|
|
}
|
|
if debugDisco {
|
|
c.logf("magicsock: disco: got disco-looking frame from %v", sender.ShortString())
|
|
}
|
|
if c.privateKey.IsZero() {
|
|
// Ignore disco messages when we're stopped.
|
|
// Still return true, to not pass it down to wireguard.
|
|
return
|
|
}
|
|
if c.discoPrivate.IsZero() {
|
|
if debugDisco {
|
|
c.logf("magicsock: disco: ignoring disco-looking frame, no local key")
|
|
}
|
|
return
|
|
}
|
|
|
|
if !c.peerMap.anyEndpointForDiscoKey(sender) {
|
|
if debugDisco {
|
|
c.logf("magicsock: disco: ignoring disco-looking frame, don't know endpoint for %v", sender.ShortString())
|
|
}
|
|
return
|
|
}
|
|
|
|
// We're now reasonably sure we're expecting communication from
|
|
// this peer, do the heavy crypto lifting to see what they want.
|
|
//
|
|
// From here on, peerNode and de are non-nil.
|
|
|
|
di := c.discoInfoLocked(sender)
|
|
|
|
var nonce [disco.NonceLen]byte
|
|
copy(nonce[:], msg[len(disco.Magic)+key.NodePublic{}.RawLen():])
|
|
sealedBox := msg[headerLen:]
|
|
payload, ok := box.OpenAfterPrecomputation(nil, sealedBox, &nonce, di.sharedKey)
|
|
if !ok {
|
|
// This might be have been intended for a previous
|
|
// disco key. When we restart we get a new disco key
|
|
// and old packets might've still been in flight (or
|
|
// scheduled). This is particularly the case for LANs
|
|
// or non-NATed endpoints.
|
|
// Don't log in normal case. Pass on to wireguard, in case
|
|
// it's actually a wireguard packet (super unlikely,
|
|
// but).
|
|
if debugDisco {
|
|
c.logf("magicsock: disco: failed to open naclbox from %v (wrong rcpt?)", sender)
|
|
}
|
|
// TODO(bradfitz): add some counter for this that logs rarely
|
|
return
|
|
}
|
|
|
|
dm, err := disco.Parse(payload)
|
|
if debugDisco {
|
|
c.logf("magicsock: disco: disco.Parse = %T, %v", dm, err)
|
|
}
|
|
if err != nil {
|
|
// Couldn't parse it, but it was inside a correctly
|
|
// signed box, so just ignore it, assuming it's from a
|
|
// newer version of Tailscale that we don't
|
|
// understand. Not even worth logging about, lest it
|
|
// be too spammy for old clients.
|
|
// TODO(bradfitz): add some counter for this that logs rarely
|
|
return
|
|
}
|
|
|
|
switch dm := dm.(type) {
|
|
case *disco.Ping:
|
|
c.handlePingLocked(dm, src, di, derpNodeSrc)
|
|
case *disco.Pong:
|
|
// There might be multiple nodes for the sender's DiscoKey.
|
|
// Ask each to handle it, stopping once one reports that
|
|
// the Pong's TxID was theirs.
|
|
handled := false
|
|
c.peerMap.forEachEndpointWithDiscoKey(sender, func(ep *endpoint) {
|
|
if !handled && ep.handlePongConnLocked(dm, di, src) {
|
|
handled = true
|
|
}
|
|
})
|
|
case *disco.CallMeMaybe:
|
|
if src.IP() != derpMagicIPAddr || derpNodeSrc.IsZero() {
|
|
// CallMeMaybe messages should only come via DERP.
|
|
c.logf("[unexpected] CallMeMaybe packets should only come via DERP")
|
|
return
|
|
}
|
|
nodeKey := tailcfg.NodeKey(derpNodeSrc)
|
|
ep, ok := c.peerMap.endpointForNodeKey(nodeKey)
|
|
if !ok {
|
|
c.logf("magicsock: disco: ignoring CallMeMaybe from %v; %v is unknown", sender.ShortString(), derpNodeSrc.ShortString())
|
|
return
|
|
}
|
|
if !ep.canP2P() {
|
|
return
|
|
}
|
|
if ep.discoKey != di.discoKey {
|
|
c.logf("[unexpected] CallMeMaybe from peer via DERP whose netmap discokey != disco source")
|
|
return
|
|
}
|
|
di.setNodeKey(nodeKey)
|
|
c.logf("[v1] magicsock: disco: %v<-%v (%v, %v) got call-me-maybe, %d endpoints",
|
|
c.discoShort, ep.discoShort,
|
|
ep.publicKey.ShortString(), derpStr(src.String()),
|
|
len(dm.MyNumber))
|
|
go ep.handleCallMeMaybe(dm)
|
|
}
|
|
return
|
|
}
|
|
|
|
// unambiguousNodeKeyOfPingLocked attempts to look up an unambiguous mapping
|
|
// from a DiscoKey dk (which sent ping dm) to a NodeKey. ok is true
|
|
// if there's the NodeKey is known unambiguously.
|
|
//
|
|
// derpNodeSrc is non-zero if the disco ping arrived via DERP.
|
|
//
|
|
// c.mu must be held.
|
|
func (c *Conn) unambiguousNodeKeyOfPingLocked(dm *disco.Ping, dk tailcfg.DiscoKey, derpNodeSrc tailcfg.NodeKey) (nk tailcfg.NodeKey, ok bool) {
|
|
if !derpNodeSrc.IsZero() {
|
|
if ep, ok := c.peerMap.endpointForNodeKey(derpNodeSrc); ok && ep.discoKey == dk {
|
|
return derpNodeSrc, true
|
|
}
|
|
}
|
|
|
|
// Pings after 1.16.0 contains its node source. See if it maps back.
|
|
if !dm.NodeKey.IsZero() {
|
|
if ep, ok := c.peerMap.endpointForNodeKey(dm.NodeKey); ok && ep.discoKey == dk {
|
|
return dm.NodeKey, true
|
|
}
|
|
}
|
|
|
|
// If there's exactly 1 node in our netmap with DiscoKey dk,
|
|
// then it's not ambiguous which node key dm was from.
|
|
if set := c.peerMap.nodesOfDisco[dk]; len(set) == 1 {
|
|
for nk = range set {
|
|
return nk, true
|
|
}
|
|
}
|
|
|
|
return nk, false
|
|
}
|
|
|
|
// di is the discoInfo of the source of the ping.
|
|
// derpNodeSrc is non-zero if the ping arrived via DERP.
|
|
func (c *Conn) handlePingLocked(dm *disco.Ping, src netaddr.IPPort, di *discoInfo, derpNodeSrc tailcfg.NodeKey) {
|
|
likelyHeartBeat := src == di.lastPingFrom && time.Since(di.lastPingTime) < 5*time.Second
|
|
di.lastPingFrom = src
|
|
di.lastPingTime = time.Now()
|
|
isDerp := src.IP() == derpMagicIPAddr
|
|
|
|
// If we can figure out with certainty which node key this disco
|
|
// message is for, eagerly update our IP<>node and disco<>node
|
|
// mappings to make p2p path discovery faster in simple
|
|
// cases. Without this, disco would still work, but would be
|
|
// reliant on DERP call-me-maybe to establish the disco<>node
|
|
// mapping, and on subsequent disco handlePongLocked to establish
|
|
// the IP<>disco mapping.
|
|
if nk, ok := c.unambiguousNodeKeyOfPingLocked(dm, di.discoKey, derpNodeSrc); ok {
|
|
di.setNodeKey(nk)
|
|
if !isDerp {
|
|
c.peerMap.setNodeKeyForIPPort(src, nk)
|
|
}
|
|
}
|
|
|
|
// If we got a ping over DERP, then derpNodeSrc is non-zero and we reply
|
|
// over DERP (in which case ipDst is also a DERP address).
|
|
// But if the ping was over UDP (ipDst is not a DERP address), then dstKey
|
|
// will be zero here, but that's fine: sendDiscoMessage only requires
|
|
// a dstKey if the dst ip:port is DERP.
|
|
dstKey := derpNodeSrc
|
|
|
|
// Remember this route if not present.
|
|
var numNodes int
|
|
if isDerp {
|
|
if ep, ok := c.peerMap.endpointForNodeKey(derpNodeSrc); ok {
|
|
ep.addCandidateEndpoint(src)
|
|
numNodes = 1
|
|
}
|
|
} else {
|
|
c.peerMap.forEachEndpointWithDiscoKey(di.discoKey, func(ep *endpoint) {
|
|
ep.addCandidateEndpoint(src)
|
|
numNodes++
|
|
if numNodes == 1 && dstKey.IsZero() {
|
|
dstKey = ep.publicKey
|
|
}
|
|
})
|
|
if numNodes > 1 {
|
|
// Zero it out if it's ambiguous, so sendDiscoMessage logging
|
|
// isn't confusing.
|
|
dstKey = tailcfg.NodeKey{}
|
|
}
|
|
}
|
|
|
|
if numNodes == 0 {
|
|
c.logf("[unexpected] got disco ping from %v/%v for node not in peers", src, derpNodeSrc)
|
|
return
|
|
}
|
|
|
|
if !likelyHeartBeat || debugDisco {
|
|
pingNodeSrcStr := dstKey.ShortString()
|
|
if numNodes > 1 {
|
|
pingNodeSrcStr = "[one-of-multi]"
|
|
}
|
|
c.logf("[v1] magicsock: disco: %v<-%v (%v, %v) got ping tx=%x", c.discoShort, di.discoShort, pingNodeSrcStr, src, dm.TxID[:6])
|
|
}
|
|
|
|
ipDst := src
|
|
discoDest := di.discoKey
|
|
go c.sendDiscoMessage(ipDst, dstKey, discoDest, &disco.Pong{
|
|
TxID: dm.TxID,
|
|
Src: src,
|
|
}, discoVerboseLog)
|
|
}
|
|
|
|
// enqueueCallMeMaybe schedules a send of disco.CallMeMaybe to de via derpAddr
|
|
// once we know that our STUN endpoint is fresh.
|
|
//
|
|
// derpAddr is de.derpAddr at the time of send. It's assumed the peer won't be
|
|
// flipping primary DERPs in the 0-30ms it takes to confirm our STUN endpoint.
|
|
// If they do, traffic will just go over DERP for a bit longer until the next
|
|
// discovery round.
|
|
func (c *Conn) enqueueCallMeMaybe(derpAddr netaddr.IPPort, de *endpoint) {
|
|
c.mu.Lock()
|
|
defer c.mu.Unlock()
|
|
|
|
if !c.lastEndpointsTime.After(time.Now().Add(-endpointsFreshEnoughDuration)) {
|
|
c.logf("magicsock: want call-me-maybe but endpoints stale; restunning")
|
|
if c.onEndpointRefreshed == nil {
|
|
c.onEndpointRefreshed = map[*endpoint]func(){}
|
|
}
|
|
c.onEndpointRefreshed[de] = func() {
|
|
c.logf("magicsock: STUN done; sending call-me-maybe to %v %v", de.discoShort, de.publicKey.ShortString())
|
|
c.enqueueCallMeMaybe(derpAddr, de)
|
|
}
|
|
// TODO(bradfitz): make a new 'reSTUNQuickly' method
|
|
// that passes down a do-a-lite-netcheck flag down to
|
|
// netcheck that does 1 (or 2 max) STUN queries
|
|
// (UDP-only, not HTTPs) to find our port mapping to
|
|
// our home DERP and maybe one other. For now we do a
|
|
// "full" ReSTUN which may or may not be a full one
|
|
// (depending on age) and may do HTTPS timing queries
|
|
// (if UDP is blocked). Good enough for now.
|
|
go c.ReSTUN("refresh-for-peering")
|
|
return
|
|
}
|
|
|
|
eps := make([]netaddr.IPPort, 0, len(c.lastEndpoints))
|
|
for _, ep := range c.lastEndpoints {
|
|
eps = append(eps, ep.Addr)
|
|
}
|
|
go de.sendDiscoMessage(derpAddr, &disco.CallMeMaybe{MyNumber: eps}, discoLog)
|
|
}
|
|
|
|
// discoInfoLocked returns the previous or new discoInfo for k.
|
|
//
|
|
// c.mu must be held.
|
|
func (c *Conn) discoInfoLocked(k tailcfg.DiscoKey) *discoInfo {
|
|
di, ok := c.discoInfo[k]
|
|
if !ok {
|
|
di = &discoInfo{
|
|
discoKey: k,
|
|
discoShort: k.ShortString(),
|
|
sharedKey: new([32]byte),
|
|
}
|
|
box.Precompute(di.sharedKey, key.Public(k).B32(), c.discoPrivate.B32())
|
|
c.discoInfo[k] = di
|
|
}
|
|
return di
|
|
}
|
|
|
|
func (c *Conn) SetNetworkUp(up bool) {
|
|
c.mu.Lock()
|
|
defer c.mu.Unlock()
|
|
if c.networkUp.Get() == up {
|
|
return
|
|
}
|
|
|
|
c.logf("magicsock: SetNetworkUp(%v)", up)
|
|
c.networkUp.Set(up)
|
|
|
|
if up {
|
|
c.startDerpHomeConnectLocked()
|
|
} else {
|
|
c.portMapper.NoteNetworkDown()
|
|
c.closeAllDerpLocked("network-down")
|
|
}
|
|
}
|
|
|
|
// SetPreferredPort sets the connection's preferred local port.
|
|
func (c *Conn) SetPreferredPort(port uint16) {
|
|
if uint16(c.port.Get()) == port {
|
|
return
|
|
}
|
|
c.port.Set(uint32(port))
|
|
|
|
if err := c.rebind(dropCurrentPort); err != nil {
|
|
c.logf("%w", err)
|
|
return
|
|
}
|
|
c.resetEndpointStates()
|
|
}
|
|
|
|
// SetPrivateKey sets the connection's private key.
|
|
//
|
|
// This is only used to be able prove our identity when connecting to
|
|
// DERP servers.
|
|
//
|
|
// If the private key changes, any DERP connections are torn down &
|
|
// recreated when needed.
|
|
func (c *Conn) SetPrivateKey(privateKey key.NodePrivate) error {
|
|
c.mu.Lock()
|
|
defer c.mu.Unlock()
|
|
|
|
oldKey, newKey := c.privateKey, privateKey
|
|
if newKey.Equal(oldKey) {
|
|
return nil
|
|
}
|
|
c.privateKey = newKey
|
|
c.havePrivateKey.Set(!newKey.IsZero())
|
|
|
|
if newKey.IsZero() {
|
|
c.publicKeyAtomic.Store(tailcfg.NodeKey{})
|
|
} else {
|
|
c.publicKeyAtomic.Store(tailcfg.NodeKeyFromNodePublic(newKey.Public()))
|
|
}
|
|
|
|
if oldKey.IsZero() {
|
|
c.everHadKey = true
|
|
c.logf("magicsock: SetPrivateKey called (init)")
|
|
go c.ReSTUN("set-private-key")
|
|
} else if newKey.IsZero() {
|
|
c.logf("magicsock: SetPrivateKey called (zeroed)")
|
|
c.closeAllDerpLocked("zero-private-key")
|
|
c.stopPeriodicReSTUNTimerLocked()
|
|
c.onEndpointRefreshed = nil
|
|
} else {
|
|
c.logf("magicsock: SetPrivateKey called (changed)")
|
|
c.closeAllDerpLocked("new-private-key")
|
|
}
|
|
|
|
// Key changed. Close existing DERP connections and reconnect to home.
|
|
if c.myDerp != 0 && !newKey.IsZero() {
|
|
c.logf("magicsock: private key changed, reconnecting to home derp-%d", c.myDerp)
|
|
c.startDerpHomeConnectLocked()
|
|
}
|
|
|
|
if newKey.IsZero() {
|
|
c.peerMap.forEachEndpoint(func(ep *endpoint) {
|
|
ep.stopAndReset()
|
|
})
|
|
}
|
|
|
|
return nil
|
|
}
|
|
|
|
// UpdatePeers is called when the set of WireGuard peers changes. It
|
|
// then removes any state for old peers.
|
|
//
|
|
// The caller passes ownership of newPeers map to UpdatePeers.
|
|
func (c *Conn) UpdatePeers(newPeers map[key.NodePublic]struct{}) {
|
|
c.mu.Lock()
|
|
defer c.mu.Unlock()
|
|
|
|
oldPeers := c.peerSet
|
|
c.peerSet = newPeers
|
|
|
|
// Clean up any key.NodePublic-keyed maps for peers that no longer
|
|
// exist.
|
|
for peer := range oldPeers {
|
|
if _, ok := newPeers[peer]; !ok {
|
|
delete(c.derpRoute, peer)
|
|
delete(c.peerLastDerp, peer)
|
|
}
|
|
}
|
|
|
|
if len(oldPeers) == 0 && len(newPeers) > 0 {
|
|
go c.ReSTUN("non-zero-peers")
|
|
}
|
|
}
|
|
|
|
// SetDERPMap controls which (if any) DERP servers are used.
|
|
// A nil value means to disable DERP; it's disabled by default.
|
|
func (c *Conn) SetDERPMap(dm *tailcfg.DERPMap) {
|
|
c.mu.Lock()
|
|
defer c.mu.Unlock()
|
|
|
|
if reflect.DeepEqual(dm, c.derpMap) {
|
|
return
|
|
}
|
|
|
|
c.derpMap = dm
|
|
if dm == nil {
|
|
c.closeAllDerpLocked("derp-disabled")
|
|
return
|
|
}
|
|
|
|
go c.ReSTUN("derp-map-update")
|
|
}
|
|
|
|
func nodesEqual(x, y []*tailcfg.Node) bool {
|
|
if len(x) != len(y) {
|
|
return false
|
|
}
|
|
for i := range x {
|
|
if !x[i].Equal(y[i]) {
|
|
return false
|
|
}
|
|
}
|
|
return true
|
|
}
|
|
|
|
// SetNetworkMap is called when the control client gets a new network
|
|
// map from the control server. It must always be non-nil.
|
|
//
|
|
// It should not use the DERPMap field of NetworkMap; that's
|
|
// conditionally sent to SetDERPMap instead.
|
|
func (c *Conn) SetNetworkMap(nm *netmap.NetworkMap) {
|
|
c.mu.Lock()
|
|
defer c.mu.Unlock()
|
|
|
|
if c.closed {
|
|
return
|
|
}
|
|
|
|
if c.netMap != nil && nodesEqual(c.netMap.Peers, nm.Peers) {
|
|
return
|
|
}
|
|
|
|
numNoDisco := 0
|
|
for _, n := range nm.Peers {
|
|
if n.DiscoKey.IsZero() {
|
|
numNoDisco++
|
|
}
|
|
}
|
|
|
|
c.logf("[v1] magicsock: got updated network map; %d peers", len(nm.Peers))
|
|
if numNoDisco != 0 {
|
|
c.logf("[v1] magicsock: %d DERP-only peers (no discokey)", numNoDisco)
|
|
}
|
|
c.netMap = nm
|
|
|
|
// Try a pass of just upserting nodes and creating missing
|
|
// endpoints. If the set of nodes is the same, this is an
|
|
// efficient alloc-free update. If the set of nodes is different,
|
|
// we'll fall through to the next pass, which allocates but can
|
|
// handle full set updates.
|
|
for _, n := range nm.Peers {
|
|
if ep, ok := c.peerMap.endpointForNodeKey(n.Key); ok {
|
|
ep.updateFromNode(n)
|
|
c.peerMap.upsertEndpoint(ep) // maybe update discokey mappings in peerMap
|
|
continue
|
|
}
|
|
|
|
ep := &endpoint{
|
|
c: c,
|
|
publicKey: n.Key,
|
|
sentPing: map[stun.TxID]sentPing{},
|
|
endpointState: map[netaddr.IPPort]*endpointState{},
|
|
}
|
|
if !n.DiscoKey.IsZero() {
|
|
ep.discoKey = n.DiscoKey
|
|
ep.discoShort = n.DiscoKey.ShortString()
|
|
}
|
|
ep.wgEndpoint = key.NodePublicFromRaw32(mem.B(n.Key[:])).UntypedHexString()
|
|
ep.initFakeUDPAddr()
|
|
c.logf("magicsock: created endpoint key=%s: disco=%s; %v", n.Key.ShortString(), n.DiscoKey.ShortString(), logger.ArgWriter(func(w *bufio.Writer) {
|
|
const derpPrefix = "127.3.3.40:"
|
|
if strings.HasPrefix(n.DERP, derpPrefix) {
|
|
ipp, _ := netaddr.ParseIPPort(n.DERP)
|
|
regionID := int(ipp.Port())
|
|
code := c.derpRegionCodeLocked(regionID)
|
|
if code != "" {
|
|
code = "(" + code + ")"
|
|
}
|
|
fmt.Fprintf(w, "derp=%v%s ", regionID, code)
|
|
}
|
|
|
|
for _, a := range n.AllowedIPs {
|
|
if a.IsSingleIP() {
|
|
fmt.Fprintf(w, "aip=%v ", a.IP())
|
|
} else {
|
|
fmt.Fprintf(w, "aip=%v ", a)
|
|
}
|
|
}
|
|
for _, ep := range n.Endpoints {
|
|
fmt.Fprintf(w, "ep=%v ", ep)
|
|
}
|
|
}))
|
|
ep.updateFromNode(n)
|
|
c.peerMap.upsertEndpoint(ep)
|
|
}
|
|
|
|
// If the set of nodes changed since the last SetNetworkMap, the
|
|
// upsert loop just above made c.peerMap contain the union of the
|
|
// old and new peers - which will be larger than the set from the
|
|
// current netmap. If that happens, go through the allocful
|
|
// deletion path to clean up moribund nodes.
|
|
if c.peerMap.nodeCount() != len(nm.Peers) {
|
|
keep := make(map[tailcfg.NodeKey]bool, len(nm.Peers))
|
|
for _, n := range nm.Peers {
|
|
keep[n.Key] = true
|
|
}
|
|
c.peerMap.forEachEndpoint(func(ep *endpoint) {
|
|
if !keep[ep.publicKey] {
|
|
c.peerMap.deleteEndpoint(ep)
|
|
}
|
|
})
|
|
}
|
|
|
|
// discokeys might have changed in the above. Discard unused info.
|
|
for dk := range c.discoInfo {
|
|
if !c.peerMap.anyEndpointForDiscoKey(dk) {
|
|
delete(c.discoInfo, dk)
|
|
}
|
|
}
|
|
}
|
|
|
|
func (c *Conn) wantDerpLocked() bool { return c.derpMap != nil }
|
|
|
|
// c.mu must be held.
|
|
func (c *Conn) closeAllDerpLocked(why string) {
|
|
if len(c.activeDerp) == 0 {
|
|
return // without the useless log statement
|
|
}
|
|
for i := range c.activeDerp {
|
|
c.closeDerpLocked(i, why)
|
|
}
|
|
c.logActiveDerpLocked()
|
|
}
|
|
|
|
// c.mu must be held.
|
|
// It is the responsibility of the caller to call logActiveDerpLocked after any set of closes.
|
|
func (c *Conn) closeDerpLocked(node int, why string) {
|
|
if ad, ok := c.activeDerp[node]; ok {
|
|
c.logf("magicsock: closing connection to derp-%v (%v), age %v", node, why, time.Since(ad.createTime).Round(time.Second))
|
|
go ad.c.Close()
|
|
ad.cancel()
|
|
delete(c.activeDerp, node)
|
|
}
|
|
}
|
|
|
|
// c.mu must be held.
|
|
func (c *Conn) logActiveDerpLocked() {
|
|
now := time.Now()
|
|
c.logf("magicsock: %v active derp conns%s", len(c.activeDerp), logger.ArgWriter(func(buf *bufio.Writer) {
|
|
if len(c.activeDerp) == 0 {
|
|
return
|
|
}
|
|
buf.WriteString(":")
|
|
c.foreachActiveDerpSortedLocked(func(node int, ad activeDerp) {
|
|
fmt.Fprintf(buf, " derp-%d=cr%v,wr%v", node, simpleDur(now.Sub(ad.createTime)), simpleDur(now.Sub(*ad.lastWrite)))
|
|
})
|
|
}))
|
|
}
|
|
|
|
func (c *Conn) logEndpointChange(endpoints []tailcfg.Endpoint) {
|
|
c.logf("magicsock: endpoints changed: %s", logger.ArgWriter(func(buf *bufio.Writer) {
|
|
for i, ep := range endpoints {
|
|
if i > 0 {
|
|
buf.WriteString(", ")
|
|
}
|
|
fmt.Fprintf(buf, "%s (%s)", ep.Addr, ep.Type)
|
|
}
|
|
}))
|
|
}
|
|
|
|
// c.mu must be held.
|
|
func (c *Conn) foreachActiveDerpSortedLocked(fn func(regionID int, ad activeDerp)) {
|
|
if len(c.activeDerp) < 2 {
|
|
for id, ad := range c.activeDerp {
|
|
fn(id, ad)
|
|
}
|
|
return
|
|
}
|
|
ids := make([]int, 0, len(c.activeDerp))
|
|
for id := range c.activeDerp {
|
|
ids = append(ids, id)
|
|
}
|
|
sort.Ints(ids)
|
|
for _, id := range ids {
|
|
fn(id, c.activeDerp[id])
|
|
}
|
|
}
|
|
|
|
func (c *Conn) cleanStaleDerp() {
|
|
c.mu.Lock()
|
|
defer c.mu.Unlock()
|
|
if c.closed {
|
|
return
|
|
}
|
|
c.derpCleanupTimerArmed = false
|
|
|
|
tooOld := time.Now().Add(-derpInactiveCleanupTime)
|
|
dirty := false
|
|
someNonHomeOpen := false
|
|
for i, ad := range c.activeDerp {
|
|
if i == c.myDerp {
|
|
continue
|
|
}
|
|
if ad.lastWrite.Before(tooOld) {
|
|
c.closeDerpLocked(i, "idle")
|
|
dirty = true
|
|
} else {
|
|
someNonHomeOpen = true
|
|
}
|
|
}
|
|
if dirty {
|
|
c.logActiveDerpLocked()
|
|
}
|
|
if someNonHomeOpen {
|
|
c.scheduleCleanStaleDerpLocked()
|
|
}
|
|
}
|
|
|
|
func (c *Conn) scheduleCleanStaleDerpLocked() {
|
|
if c.derpCleanupTimerArmed {
|
|
// Already going to fire soon. Let the existing one
|
|
// fire lest it get infinitely delayed by repeated
|
|
// calls to scheduleCleanStaleDerpLocked.
|
|
return
|
|
}
|
|
c.derpCleanupTimerArmed = true
|
|
if c.derpCleanupTimer != nil {
|
|
c.derpCleanupTimer.Reset(derpCleanStaleInterval)
|
|
} else {
|
|
c.derpCleanupTimer = time.AfterFunc(derpCleanStaleInterval, c.cleanStaleDerp)
|
|
}
|
|
}
|
|
|
|
// DERPs reports the number of active DERP connections.
|
|
func (c *Conn) DERPs() int {
|
|
c.mu.Lock()
|
|
defer c.mu.Unlock()
|
|
|
|
return len(c.activeDerp)
|
|
}
|
|
|
|
// Bind returns the wireguard-go conn.Bind for c.
|
|
func (c *Conn) Bind() conn.Bind {
|
|
return c.bind
|
|
}
|
|
|
|
// connBind is a wireguard-go conn.Bind for a Conn.
|
|
// It bridges the behavior of wireguard-go and a Conn.
|
|
// wireguard-go calls Close then Open on device.Up.
|
|
// That won't work well for a Conn, which is only closed on shutdown.
|
|
// The subsequent Close is a real close.
|
|
type connBind struct {
|
|
*Conn
|
|
mu sync.Mutex
|
|
closed bool
|
|
}
|
|
|
|
// Open is called by WireGuard to create a UDP binding.
|
|
// The ignoredPort comes from wireguard-go, via the wgcfg config.
|
|
// We ignore that port value here, since we have the local port available easily.
|
|
func (c *connBind) Open(ignoredPort uint16) ([]conn.ReceiveFunc, uint16, error) {
|
|
c.mu.Lock()
|
|
defer c.mu.Unlock()
|
|
if !c.closed {
|
|
return nil, 0, errors.New("magicsock: connBind already open")
|
|
}
|
|
c.closed = false
|
|
fns := []conn.ReceiveFunc{c.receiveIPv4, c.receiveIPv6, c.receiveDERP}
|
|
if runtime.GOOS == "js" {
|
|
fns = []conn.ReceiveFunc{c.receiveDERP}
|
|
}
|
|
// TODO: Combine receiveIPv4 and receiveIPv6 and receiveIP into a single
|
|
// closure that closes over a *RebindingUDPConn?
|
|
return fns, c.LocalPort(), nil
|
|
}
|
|
|
|
// SetMark is used by wireguard-go to set a mark bit for packets to avoid routing loops.
|
|
// We handle that ourselves elsewhere.
|
|
func (c *connBind) SetMark(value uint32) error {
|
|
return nil
|
|
}
|
|
|
|
// Close closes the connBind, unless it is already closed.
|
|
func (c *connBind) Close() error {
|
|
c.mu.Lock()
|
|
defer c.mu.Unlock()
|
|
if c.closed {
|
|
return nil
|
|
}
|
|
c.closed = true
|
|
// Unblock all outstanding receives.
|
|
if c.pconn4 != nil {
|
|
c.pconn4.Close()
|
|
}
|
|
if c.pconn6 != nil {
|
|
c.pconn6.Close()
|
|
}
|
|
// Send an empty read result to unblock receiveDERP,
|
|
// which will then check connBind.Closed.
|
|
c.derpRecvCh <- derpReadResult{}
|
|
return nil
|
|
}
|
|
|
|
// Closed reports whether c is closed.
|
|
func (c *connBind) Closed() bool {
|
|
c.mu.Lock()
|
|
defer c.mu.Unlock()
|
|
return c.closed
|
|
}
|
|
|
|
// Close closes the connection.
|
|
//
|
|
// Only the first close does anything. Any later closes return nil.
|
|
func (c *Conn) Close() error {
|
|
c.mu.Lock()
|
|
defer c.mu.Unlock()
|
|
if c.closed {
|
|
return nil
|
|
}
|
|
if c.derpCleanupTimerArmed {
|
|
c.derpCleanupTimer.Stop()
|
|
}
|
|
c.stopPeriodicReSTUNTimerLocked()
|
|
c.portMapper.Close()
|
|
|
|
c.peerMap.forEachEndpoint(func(ep *endpoint) {
|
|
ep.stopAndReset()
|
|
})
|
|
|
|
c.closed = true
|
|
c.connCtxCancel()
|
|
c.closeAllDerpLocked("conn-close")
|
|
// Ignore errors from c.pconnN.Close.
|
|
// They will frequently have been closed already by a call to connBind.Close.
|
|
if c.pconn6 != nil {
|
|
c.pconn6.Close()
|
|
}
|
|
if c.pconn4 != nil {
|
|
c.pconn4.Close()
|
|
}
|
|
|
|
// Wait on goroutines updating right at the end, once everything is
|
|
// already closed. We want everything else in the Conn to be
|
|
// consistently in the closed state before we release mu to wait
|
|
// on the endpoint updater & derphttp.Connect.
|
|
for c.goroutinesRunningLocked() {
|
|
c.muCond.Wait()
|
|
}
|
|
return nil
|
|
}
|
|
|
|
func (c *Conn) goroutinesRunningLocked() bool {
|
|
if c.endpointsUpdateActive {
|
|
return true
|
|
}
|
|
// The goroutine running dc.Connect in derpWriteChanOfAddr may linger
|
|
// and appear to leak, as observed in https://github.com/tailscale/tailscale/issues/554.
|
|
// This is despite the underlying context being cancelled by connCtxCancel above.
|
|
// To avoid this condition, we must wait on derpStarted here
|
|
// to ensure that this goroutine has exited by the time Close returns.
|
|
// We only do this if derpWriteChanOfAddr has executed at least once:
|
|
// on the first run, it sets firstDerp := true and spawns the aforementioned goroutine.
|
|
// To detect this, we check activeDerp, which is initialized to non-nil on the first run.
|
|
if c.activeDerp != nil {
|
|
select {
|
|
case <-c.derpStarted:
|
|
break
|
|
default:
|
|
return true
|
|
}
|
|
}
|
|
return false
|
|
}
|
|
|
|
func maxIdleBeforeSTUNShutdown() time.Duration {
|
|
if debugReSTUNStopOnIdle {
|
|
return 45 * time.Second
|
|
}
|
|
return sessionActiveTimeout
|
|
}
|
|
|
|
func (c *Conn) shouldDoPeriodicReSTUNLocked() bool {
|
|
if c.networkDown() {
|
|
return false
|
|
}
|
|
if len(c.peerSet) == 0 || c.privateKey.IsZero() {
|
|
// If no peers, not worth doing.
|
|
// Also don't if there's no key (not running).
|
|
return false
|
|
}
|
|
if f := c.idleFunc; f != nil {
|
|
idleFor := f()
|
|
if debugReSTUNStopOnIdle {
|
|
c.logf("magicsock: periodicReSTUN: idle for %v", idleFor.Round(time.Second))
|
|
}
|
|
if idleFor > maxIdleBeforeSTUNShutdown() {
|
|
if c.netMap != nil && c.netMap.Debug != nil && c.netMap.Debug.ForceBackgroundSTUN {
|
|
// Overridden by control.
|
|
return true
|
|
}
|
|
return false
|
|
}
|
|
}
|
|
return true
|
|
}
|
|
|
|
func (c *Conn) onPortMapChanged() { c.ReSTUN("portmap-changed") }
|
|
|
|
// ReSTUN triggers an address discovery.
|
|
// The provided why string is for debug logging only.
|
|
func (c *Conn) ReSTUN(why string) {
|
|
c.mu.Lock()
|
|
defer c.mu.Unlock()
|
|
if c.closed {
|
|
// raced with a shutdown.
|
|
return
|
|
}
|
|
|
|
// If the user stopped the app, stop doing work. (When the
|
|
// user stops Tailscale via the GUI apps, ipn/local.go
|
|
// reconfigures the engine with a zero private key.)
|
|
//
|
|
// This used to just check c.privateKey.IsZero, but that broke
|
|
// some end-to-end tests tests that didn't ever set a private
|
|
// key somehow. So for now, only stop doing work if we ever
|
|
// had a key, which helps real users, but appeases tests for
|
|
// now. TODO: rewrite those tests to be less brittle or more
|
|
// realistic.
|
|
if c.privateKey.IsZero() && c.everHadKey {
|
|
c.logf("magicsock: ReSTUN(%q) ignored; stopped, no private key", why)
|
|
return
|
|
}
|
|
|
|
if c.endpointsUpdateActive {
|
|
if c.wantEndpointsUpdate != why {
|
|
c.logf("[v1] magicsock: ReSTUN: endpoint update active, need another later (%q)", why)
|
|
c.wantEndpointsUpdate = why
|
|
}
|
|
} else {
|
|
c.endpointsUpdateActive = true
|
|
go c.updateEndpoints(why)
|
|
}
|
|
}
|
|
|
|
func (c *Conn) initialBind() error {
|
|
if runtime.GOOS == "js" {
|
|
return nil
|
|
}
|
|
if err := c.bindSocket(&c.pconn4, "udp4", keepCurrentPort); err != nil {
|
|
return fmt.Errorf("magicsock: initialBind IPv4 failed: %w", err)
|
|
}
|
|
c.portMapper.SetLocalPort(c.LocalPort())
|
|
if err := c.bindSocket(&c.pconn6, "udp6", keepCurrentPort); err != nil {
|
|
c.logf("magicsock: ignoring IPv6 bind failure: %v", err)
|
|
}
|
|
return nil
|
|
}
|
|
|
|
// listenPacket opens a packet listener.
|
|
// The network must be "udp4" or "udp6".
|
|
func (c *Conn) listenPacket(network string, port uint16) (net.PacketConn, error) {
|
|
ctx := context.Background() // unused without DNS name to resolve
|
|
addr := net.JoinHostPort("", fmt.Sprint(port))
|
|
if c.testOnlyPacketListener != nil {
|
|
return c.testOnlyPacketListener.ListenPacket(ctx, network, addr)
|
|
}
|
|
return netns.Listener().ListenPacket(ctx, network, addr)
|
|
}
|
|
|
|
// bindSocket initializes rucPtr if necessary and binds a UDP socket to it.
|
|
// Network indicates the UDP socket type; it must be "udp4" or "udp6".
|
|
// If rucPtr had an existing UDP socket bound, it closes that socket.
|
|
// The caller is responsible for informing the portMapper of any changes.
|
|
// If curPortFate is set to dropCurrentPort, no attempt is made to reuse
|
|
// the current port.
|
|
func (c *Conn) bindSocket(rucPtr **RebindingUDPConn, network string, curPortFate currentPortFate) error {
|
|
if *rucPtr == nil {
|
|
*rucPtr = new(RebindingUDPConn)
|
|
}
|
|
ruc := *rucPtr
|
|
|
|
// Hold the ruc lock the entire time, so that the close+bind is atomic
|
|
// from the perspective of ruc receive functions.
|
|
ruc.mu.Lock()
|
|
defer ruc.mu.Unlock()
|
|
|
|
if debugAlwaysDERP {
|
|
c.logf("disabled %v per TS_DEBUG_ALWAYS_USE_DERP", network)
|
|
ruc.pconn = newBlockForeverConn()
|
|
return nil
|
|
}
|
|
|
|
// Build a list of preferred ports.
|
|
// Best is the port that the user requested.
|
|
// Second best is the port that is currently in use.
|
|
// If those fail, fall back to 0.
|
|
var ports []uint16
|
|
if port := uint16(c.port.Get()); port != 0 {
|
|
ports = append(ports, port)
|
|
}
|
|
if ruc.pconn != nil && curPortFate == keepCurrentPort {
|
|
curPort := uint16(ruc.localAddrLocked().Port)
|
|
ports = append(ports, curPort)
|
|
}
|
|
ports = append(ports, 0)
|
|
// Remove duplicates. (All duplicates are consecutive.)
|
|
uniq.ModifySlice(&ports, func(i, j int) bool { return ports[i] == ports[j] })
|
|
|
|
var pconn net.PacketConn
|
|
for _, port := range ports {
|
|
// Close the existing conn, in case it is sitting on the port we want.
|
|
err := ruc.closeLocked()
|
|
if err != nil && !errors.Is(err, net.ErrClosed) && !errors.Is(err, errNilPConn) {
|
|
c.logf("magicsock: bindSocket %v close failed: %v", network, err)
|
|
}
|
|
// Open a new one with the desired port.
|
|
pconn, err = c.listenPacket(network, port)
|
|
if err != nil {
|
|
c.logf("magicsock: unable to bind %v port %d: %v", network, port, err)
|
|
continue
|
|
}
|
|
// Success.
|
|
ruc.pconn = pconn
|
|
if network == "udp4" {
|
|
health.SetUDP4Unbound(false)
|
|
}
|
|
return nil
|
|
}
|
|
|
|
// Failed to bind, including on port 0 (!).
|
|
// Set pconn to a dummy conn whose reads block until closed.
|
|
// This keeps the receive funcs alive for a future in which
|
|
// we get a link change and we can try binding again.
|
|
ruc.pconn = newBlockForeverConn()
|
|
if network == "udp4" {
|
|
health.SetUDP4Unbound(true)
|
|
}
|
|
return fmt.Errorf("failed to bind any ports (tried %v)", ports)
|
|
}
|
|
|
|
type currentPortFate uint8
|
|
|
|
const (
|
|
keepCurrentPort = currentPortFate(0)
|
|
dropCurrentPort = currentPortFate(1)
|
|
)
|
|
|
|
// rebind closes and re-binds the UDP sockets.
|
|
// We consider it successful if we manage to bind the IPv4 socket.
|
|
func (c *Conn) rebind(curPortFate currentPortFate) error {
|
|
if runtime.GOOS == "js" {
|
|
return nil
|
|
}
|
|
if err := c.bindSocket(&c.pconn4, "udp4", curPortFate); err != nil {
|
|
return fmt.Errorf("magicsock: Rebind IPv4 failed: %w", err)
|
|
}
|
|
c.portMapper.SetLocalPort(c.LocalPort())
|
|
if err := c.bindSocket(&c.pconn6, "udp6", curPortFate); err != nil {
|
|
c.logf("magicsock: Rebind ignoring IPv6 bind failure: %v", err)
|
|
}
|
|
return nil
|
|
}
|
|
|
|
// Rebind closes and re-binds the UDP sockets and resets the DERP connection.
|
|
// It should be followed by a call to ReSTUN.
|
|
func (c *Conn) Rebind() {
|
|
if err := c.rebind(keepCurrentPort); err != nil {
|
|
c.logf("%w", err)
|
|
return
|
|
}
|
|
|
|
c.mu.Lock()
|
|
c.closeAllDerpLocked("rebind")
|
|
if !c.privateKey.IsZero() {
|
|
c.startDerpHomeConnectLocked()
|
|
}
|
|
c.mu.Unlock()
|
|
|
|
c.resetEndpointStates()
|
|
}
|
|
|
|
// resetEndpointStates resets the preferred address for all peers.
|
|
// This is called when connectivity changes enough that we no longer
|
|
// trust the old routes.
|
|
func (c *Conn) resetEndpointStates() {
|
|
c.mu.Lock()
|
|
defer c.mu.Unlock()
|
|
c.peerMap.forEachEndpoint(func(ep *endpoint) {
|
|
ep.noteConnectivityChange()
|
|
})
|
|
}
|
|
|
|
// packIPPort packs an IPPort into the form wanted by WireGuard.
|
|
func packIPPort(ua netaddr.IPPort) []byte {
|
|
ip := ua.IP().Unmap()
|
|
a := ip.As16()
|
|
ipb := a[:]
|
|
if ip.Is4() {
|
|
ipb = ipb[12:]
|
|
}
|
|
b := make([]byte, 0, len(ipb)+2)
|
|
b = append(b, ipb...)
|
|
b = append(b, byte(ua.Port()))
|
|
b = append(b, byte(ua.Port()>>8))
|
|
return b
|
|
}
|
|
|
|
// ParseEndpoint is called by WireGuard to connect to an endpoint.
|
|
func (c *Conn) ParseEndpoint(nodeKeyStr string) (conn.Endpoint, error) {
|
|
k, err := key.ParseNodePublicUntyped(mem.S(nodeKeyStr))
|
|
if err != nil {
|
|
return nil, fmt.Errorf("magicsock: ParseEndpoint: parse failed on %q: %w", nodeKeyStr, err)
|
|
}
|
|
pk := tailcfg.NodeKeyFromNodePublic(k)
|
|
|
|
c.mu.Lock()
|
|
defer c.mu.Unlock()
|
|
if c.closed {
|
|
return nil, errConnClosed
|
|
}
|
|
ep, ok := c.peerMap.endpointForNodeKey(pk)
|
|
if !ok {
|
|
// We should never be telling WireGuard about a new peer
|
|
// before magicsock knows about it.
|
|
c.logf("[unexpected] magicsock: ParseEndpoint: unknown node key=%s", pk.ShortString())
|
|
return nil, fmt.Errorf("magicsock: ParseEndpoint: unknown peer %q", pk.ShortString())
|
|
}
|
|
|
|
return ep, nil
|
|
}
|
|
|
|
// RebindingUDPConn is a UDP socket that can be re-bound.
|
|
// Unix has no notion of re-binding a socket, so we swap it out for a new one.
|
|
type RebindingUDPConn struct {
|
|
mu sync.Mutex
|
|
pconn net.PacketConn
|
|
}
|
|
|
|
// currentConn returns c's current pconn.
|
|
func (c *RebindingUDPConn) currentConn() net.PacketConn {
|
|
c.mu.Lock()
|
|
defer c.mu.Unlock()
|
|
return c.pconn
|
|
}
|
|
|
|
// ReadFrom reads a packet from c into b.
|
|
// It returns the number of bytes copied and the source address.
|
|
func (c *RebindingUDPConn) ReadFrom(b []byte) (int, net.Addr, error) {
|
|
for {
|
|
pconn := c.currentConn()
|
|
n, addr, err := pconn.ReadFrom(b)
|
|
if err != nil && pconn != c.currentConn() {
|
|
continue
|
|
}
|
|
return n, addr, err
|
|
}
|
|
}
|
|
|
|
// ReadFromNetaddr reads a packet from c into b.
|
|
// It returns the number of bytes copied and the return address.
|
|
// It is identical to c.ReadFrom, except that it returns a netaddr.IPPort instead of a net.Addr.
|
|
// ReadFromNetaddr is designed to work with specific underlying connection types.
|
|
// If c's underlying connection returns a non-*net.UPDAddr return address, ReadFromNetaddr will return an error.
|
|
// ReadFromNetaddr exists because it removes an allocation per read,
|
|
// when c's underlying connection is a net.UDPConn.
|
|
func (c *RebindingUDPConn) ReadFromNetaddr(b []byte) (n int, ipp netaddr.IPPort, err error) {
|
|
for {
|
|
pconn := c.currentConn()
|
|
|
|
// Optimization: Treat *net.UDPConn specially.
|
|
// ReadFromUDP gets partially inlined, avoiding allocating a *net.UDPAddr,
|
|
// as long as pAddr itself doesn't escape.
|
|
// The non-*net.UDPConn case works, but it allocates.
|
|
var pAddr *net.UDPAddr
|
|
if udpConn, ok := pconn.(*net.UDPConn); ok {
|
|
n, pAddr, err = udpConn.ReadFromUDP(b)
|
|
} else {
|
|
var addr net.Addr
|
|
n, addr, err = pconn.ReadFrom(b)
|
|
if addr != nil {
|
|
pAddr, ok = addr.(*net.UDPAddr)
|
|
if !ok {
|
|
return 0, netaddr.IPPort{}, fmt.Errorf("RebindingUDPConn.ReadFromNetaddr: underlying connection returned address of type %T, want *netaddr.UDPAddr", addr)
|
|
}
|
|
}
|
|
}
|
|
|
|
if err != nil {
|
|
if pconn != c.currentConn() {
|
|
continue
|
|
}
|
|
} else {
|
|
// Convert pAddr to a netaddr.IPPort.
|
|
// This prevents pAddr from escaping.
|
|
var ok bool
|
|
ipp, ok = netaddr.FromStdAddr(pAddr.IP, pAddr.Port, pAddr.Zone)
|
|
if !ok {
|
|
return 0, netaddr.IPPort{}, errors.New("netaddr.FromStdAddr failed")
|
|
}
|
|
}
|
|
return n, ipp, err
|
|
}
|
|
}
|
|
|
|
func (c *RebindingUDPConn) LocalAddr() *net.UDPAddr {
|
|
c.mu.Lock()
|
|
defer c.mu.Unlock()
|
|
return c.localAddrLocked()
|
|
}
|
|
|
|
func (c *RebindingUDPConn) localAddrLocked() *net.UDPAddr {
|
|
return c.pconn.LocalAddr().(*net.UDPAddr)
|
|
}
|
|
|
|
// errNilPConn is returned by RebindingUDPConn.Close when there is no current pconn.
|
|
// It is for internal use only and should not be returned to users.
|
|
var errNilPConn = errors.New("nil pconn")
|
|
|
|
func (c *RebindingUDPConn) Close() error {
|
|
c.mu.Lock()
|
|
defer c.mu.Unlock()
|
|
return c.closeLocked()
|
|
}
|
|
|
|
func (c *RebindingUDPConn) closeLocked() error {
|
|
if c.pconn == nil {
|
|
return errNilPConn
|
|
}
|
|
return c.pconn.Close()
|
|
}
|
|
|
|
func (c *RebindingUDPConn) WriteTo(b []byte, addr net.Addr) (int, error) {
|
|
for {
|
|
c.mu.Lock()
|
|
pconn := c.pconn
|
|
c.mu.Unlock()
|
|
|
|
n, err := pconn.WriteTo(b, addr)
|
|
if err != nil {
|
|
c.mu.Lock()
|
|
pconn2 := c.pconn
|
|
c.mu.Unlock()
|
|
|
|
if pconn != pconn2 {
|
|
continue
|
|
}
|
|
}
|
|
return n, err
|
|
}
|
|
}
|
|
|
|
func newBlockForeverConn() *blockForeverConn {
|
|
c := new(blockForeverConn)
|
|
c.cond = sync.NewCond(&c.mu)
|
|
return c
|
|
}
|
|
|
|
// blockForeverConn is a net.PacketConn whose reads block until it is closed.
|
|
type blockForeverConn struct {
|
|
mu sync.Mutex
|
|
cond *sync.Cond
|
|
closed bool
|
|
}
|
|
|
|
func (c *blockForeverConn) ReadFrom(p []byte) (n int, addr net.Addr, err error) {
|
|
c.mu.Lock()
|
|
for !c.closed {
|
|
c.cond.Wait()
|
|
}
|
|
c.mu.Unlock()
|
|
return 0, nil, net.ErrClosed
|
|
}
|
|
|
|
func (c *blockForeverConn) WriteTo(p []byte, addr net.Addr) (n int, err error) {
|
|
// Silently drop writes.
|
|
return len(p), nil
|
|
}
|
|
|
|
func (c *blockForeverConn) LocalAddr() net.Addr {
|
|
// Return a *net.UDPAddr because lots of code assumes that it will.
|
|
return new(net.UDPAddr)
|
|
}
|
|
|
|
func (c *blockForeverConn) Close() error {
|
|
c.mu.Lock()
|
|
defer c.mu.Unlock()
|
|
if c.closed {
|
|
return net.ErrClosed
|
|
}
|
|
c.closed = true
|
|
return nil
|
|
}
|
|
|
|
func (c *blockForeverConn) SetDeadline(t time.Time) error { return errors.New("unimplemented") }
|
|
func (c *blockForeverConn) SetReadDeadline(t time.Time) error { return errors.New("unimplemented") }
|
|
func (c *blockForeverConn) SetWriteDeadline(t time.Time) error { return errors.New("unimplemented") }
|
|
|
|
// simpleDur rounds d such that it stringifies to something short.
|
|
func simpleDur(d time.Duration) time.Duration {
|
|
if d < time.Second {
|
|
return d.Round(time.Millisecond)
|
|
}
|
|
if d < time.Minute {
|
|
return d.Round(time.Second)
|
|
}
|
|
return d.Round(time.Minute)
|
|
}
|
|
|
|
func sbPrintAddr(sb *strings.Builder, a netaddr.IPPort) {
|
|
is6 := a.IP().Is6()
|
|
if is6 {
|
|
sb.WriteByte('[')
|
|
}
|
|
fmt.Fprintf(sb, "%s", a.IP())
|
|
if is6 {
|
|
sb.WriteByte(']')
|
|
}
|
|
fmt.Fprintf(sb, ":%d", a.Port())
|
|
}
|
|
|
|
func (c *Conn) derpRegionCodeOfAddrLocked(ipPort string) string {
|
|
_, portStr, err := net.SplitHostPort(ipPort)
|
|
if err != nil {
|
|
return ""
|
|
}
|
|
regionID, err := strconv.Atoi(portStr)
|
|
if err != nil {
|
|
return ""
|
|
}
|
|
return c.derpRegionCodeOfIDLocked(regionID)
|
|
}
|
|
|
|
func (c *Conn) derpRegionCodeOfIDLocked(regionID int) string {
|
|
if c.derpMap == nil {
|
|
return ""
|
|
}
|
|
if r, ok := c.derpMap.Regions[regionID]; ok {
|
|
return r.RegionCode
|
|
}
|
|
return ""
|
|
}
|
|
|
|
func (c *Conn) UpdateStatus(sb *ipnstate.StatusBuilder) {
|
|
c.mu.Lock()
|
|
defer c.mu.Unlock()
|
|
|
|
var tailAddr4 string
|
|
var tailscaleIPs []netaddr.IP
|
|
if c.netMap != nil {
|
|
tailscaleIPs = make([]netaddr.IP, 0, len(c.netMap.Addresses))
|
|
for _, addr := range c.netMap.Addresses {
|
|
if !addr.IsSingleIP() {
|
|
continue
|
|
}
|
|
sb.AddTailscaleIP(addr.IP())
|
|
// TailAddr previously only allowed for a
|
|
// single Tailscale IP. For compatibility for
|
|
// a couple releases starting with 1.8, keep
|
|
// that field pulled out separately.
|
|
if addr.IP().Is4() {
|
|
tailAddr4 = addr.IP().String()
|
|
}
|
|
tailscaleIPs = append(tailscaleIPs, addr.IP())
|
|
}
|
|
}
|
|
|
|
sb.MutateSelfStatus(func(ss *ipnstate.PeerStatus) {
|
|
if !c.privateKey.IsZero() {
|
|
ss.PublicKey = c.privateKey.Public()
|
|
} else {
|
|
ss.PublicKey = key.NodePublic{}
|
|
}
|
|
ss.Addrs = make([]string, 0, len(c.lastEndpoints))
|
|
for _, ep := range c.lastEndpoints {
|
|
ss.Addrs = append(ss.Addrs, ep.Addr.String())
|
|
}
|
|
ss.OS = version.OS()
|
|
if c.netMap != nil {
|
|
ss.HostName = c.netMap.Hostinfo.Hostname
|
|
ss.DNSName = c.netMap.Name
|
|
ss.UserID = c.netMap.User
|
|
if c.netMap.SelfNode != nil {
|
|
if c := c.netMap.SelfNode.Capabilities; len(c) > 0 {
|
|
ss.Capabilities = append([]string(nil), c...)
|
|
}
|
|
}
|
|
} else {
|
|
ss.HostName, _ = os.Hostname()
|
|
}
|
|
if c.derpMap != nil {
|
|
derpRegion, ok := c.derpMap.Regions[c.myDerp]
|
|
if ok {
|
|
ss.Relay = derpRegion.RegionCode
|
|
}
|
|
}
|
|
ss.TailscaleIPs = tailscaleIPs
|
|
ss.TailAddrDeprecated = tailAddr4
|
|
})
|
|
|
|
c.peerMap.forEachEndpoint(func(ep *endpoint) {
|
|
ps := &ipnstate.PeerStatus{InMagicSock: true}
|
|
//ps.Addrs = append(ps.Addrs, n.Endpoints...)
|
|
ep.populatePeerStatus(ps)
|
|
sb.AddPeer(key.NodePublicFromRaw32(mem.B(ep.publicKey[:])), ps)
|
|
})
|
|
|
|
c.foreachActiveDerpSortedLocked(func(node int, ad activeDerp) {
|
|
// TODO(bradfitz): add to ipnstate.StatusBuilder
|
|
//f("<li><b>derp-%v</b>: cr%v,wr%v</li>", node, simpleDur(now.Sub(ad.createTime)), simpleDur(now.Sub(*ad.lastWrite)))
|
|
})
|
|
}
|
|
|
|
func ippDebugString(ua netaddr.IPPort) string {
|
|
if ua.IP() == derpMagicIPAddr {
|
|
return fmt.Sprintf("derp-%d", ua.Port())
|
|
}
|
|
return ua.String()
|
|
}
|
|
|
|
// discoEndpoint is a wireguard/conn.Endpoint that picks the best
|
|
// available path to communicate with a peer, based on network
|
|
// conditions and what the peer supports.
|
|
type endpoint struct {
|
|
// atomically accessed; declared first for alignment reasons
|
|
lastRecv mono.Time
|
|
numStopAndResetAtomic int64
|
|
|
|
// These fields are initialized once and never modified.
|
|
c *Conn
|
|
publicKey tailcfg.NodeKey // peer public key (for WireGuard + DERP)
|
|
fakeWGAddr netaddr.IPPort // the UDP address we tell wireguard-go we're using
|
|
wgEndpoint string // string from ParseEndpoint, holds a JSON-serialized wgcfg.Endpoints
|
|
|
|
// mu protects all following fields.
|
|
mu sync.Mutex // Lock ordering: Conn.mu, then endpoint.mu
|
|
|
|
discoKey tailcfg.DiscoKey // for discovery messages. IsZero() if peer can't disco.
|
|
discoShort string // ShortString of discoKey. Empty if peer can't disco.
|
|
|
|
heartBeatTimer *time.Timer // nil when idle
|
|
lastSend mono.Time // last time there was outgoing packets sent to this peer (from wireguard-go)
|
|
lastFullPing mono.Time // last time we pinged all endpoints
|
|
derpAddr netaddr.IPPort // fallback/bootstrap path, if non-zero (non-zero for well-behaved clients)
|
|
|
|
bestAddr addrLatency // best non-DERP path; zero if none
|
|
bestAddrAt mono.Time // time best address re-confirmed
|
|
trustBestAddrUntil mono.Time // time when bestAddr expires
|
|
sentPing map[stun.TxID]sentPing
|
|
endpointState map[netaddr.IPPort]*endpointState
|
|
isCallMeMaybeEP map[netaddr.IPPort]bool
|
|
|
|
pendingCLIPings []pendingCLIPing // any outstanding "tailscale ping" commands running
|
|
}
|
|
|
|
type pendingCLIPing struct {
|
|
res *ipnstate.PingResult
|
|
cb func(*ipnstate.PingResult)
|
|
}
|
|
|
|
const (
|
|
// sessionActiveTimeout is how long since the last activity we
|
|
// try to keep an established endpoint peering alive.
|
|
// It's also the idle time at which we stop doing STUN queries to
|
|
// keep NAT mappings alive.
|
|
sessionActiveTimeout = 2 * time.Minute
|
|
|
|
// upgradeInterval is how often we try to upgrade to a better path
|
|
// even if we have some non-DERP route that works.
|
|
upgradeInterval = 1 * time.Minute
|
|
|
|
// heartbeatInterval is how often pings to the best UDP address
|
|
// are sent.
|
|
heartbeatInterval = 2 * time.Second
|
|
|
|
// trustUDPAddrDuration is how long we trust a UDP address as the exclusive
|
|
// path (without using DERP) without having heard a Pong reply.
|
|
trustUDPAddrDuration = 5 * time.Second
|
|
|
|
// goodEnoughLatency is the latency at or under which we don't
|
|
// try to upgrade to a better path.
|
|
goodEnoughLatency = 5 * time.Millisecond
|
|
|
|
// derpInactiveCleanupTime is how long a non-home DERP connection
|
|
// needs to be idle (last written to) before we close it.
|
|
derpInactiveCleanupTime = 60 * time.Second
|
|
|
|
// derpCleanStaleInterval is how often cleanStaleDerp runs when there
|
|
// are potentially-stale DERP connections to close.
|
|
derpCleanStaleInterval = 15 * time.Second
|
|
|
|
// endpointsFreshEnoughDuration is how long we consider a
|
|
// STUN-derived endpoint valid for. UDP NAT mappings typically
|
|
// expire at 30 seconds, so this is a few seconds shy of that.
|
|
endpointsFreshEnoughDuration = 27 * time.Second
|
|
)
|
|
|
|
// Constants that are variable for testing.
|
|
var (
|
|
// pingTimeoutDuration is how long we wait for a pong reply before
|
|
// assuming it's never coming.
|
|
pingTimeoutDuration = 5 * time.Second
|
|
|
|
// discoPingInterval is the minimum time between pings
|
|
// to an endpoint. (Except in the case of CallMeMaybe frames
|
|
// resetting the counter, as the first pings likely didn't through
|
|
// the firewall)
|
|
discoPingInterval = 5 * time.Second
|
|
)
|
|
|
|
// endpointState is some state and history for a specific endpoint of
|
|
// a endpoint. (The subject is the endpoint.endpointState
|
|
// map key)
|
|
type endpointState struct {
|
|
// all fields guarded by endpoint.mu
|
|
|
|
// lastPing is the last (outgoing) ping time.
|
|
lastPing mono.Time
|
|
|
|
// lastGotPing, if non-zero, means that this was an endpoint
|
|
// that we learned about at runtime (from an incoming ping)
|
|
// and that is not in the network map. If so, we keep the time
|
|
// updated and use it to discard old candidates.
|
|
lastGotPing time.Time
|
|
|
|
// callMeMaybeTime, if non-zero, is the time this endpoint
|
|
// was advertised last via a call-me-maybe disco message.
|
|
callMeMaybeTime time.Time
|
|
|
|
recentPongs []pongReply // ring buffer up to pongHistoryCount entries
|
|
recentPong uint16 // index into recentPongs of most recent; older before, wrapped
|
|
|
|
index int16 // index in nodecfg.Node.Endpoints; meaningless if lastGotPing non-zero
|
|
}
|
|
|
|
// indexSentinelDeleted is the temporary value that endpointState.index takes while
|
|
// a endpoint's endpoints are being updated from a new network map.
|
|
const indexSentinelDeleted = -1
|
|
|
|
// shouldDeleteLocked reports whether we should delete this endpoint.
|
|
func (st *endpointState) shouldDeleteLocked() bool {
|
|
switch {
|
|
case !st.callMeMaybeTime.IsZero():
|
|
return false
|
|
case st.lastGotPing.IsZero():
|
|
// This was an endpoint from the network map. Is it still in the network map?
|
|
return st.index == indexSentinelDeleted
|
|
default:
|
|
// This was an endpoint discovered at runtime.
|
|
return time.Since(st.lastGotPing) > sessionActiveTimeout
|
|
}
|
|
}
|
|
|
|
func (de *endpoint) deleteEndpointLocked(ep netaddr.IPPort) {
|
|
delete(de.endpointState, ep)
|
|
if de.bestAddr.IPPort == ep {
|
|
de.bestAddr = addrLatency{}
|
|
}
|
|
}
|
|
|
|
// pongHistoryCount is how many pongReply values we keep per endpointState
|
|
const pongHistoryCount = 64
|
|
|
|
type pongReply struct {
|
|
latency time.Duration
|
|
pongAt mono.Time // when we received the pong
|
|
from netaddr.IPPort // the pong's src (usually same as endpoint map key)
|
|
pongSrc netaddr.IPPort // what they reported they heard
|
|
}
|
|
|
|
type sentPing struct {
|
|
to netaddr.IPPort
|
|
at mono.Time
|
|
timer *time.Timer // timeout timer
|
|
purpose discoPingPurpose
|
|
}
|
|
|
|
// initFakeUDPAddr populates fakeWGAddr with a globally unique fake UDPAddr.
|
|
// The current implementation just uses the pointer value of de jammed into an IPv6
|
|
// address, but it could also be, say, a counter.
|
|
func (de *endpoint) initFakeUDPAddr() {
|
|
var addr [16]byte
|
|
addr[0] = 0xfd
|
|
addr[1] = 0x00
|
|
binary.BigEndian.PutUint64(addr[2:], uint64(reflect.ValueOf(de).Pointer()))
|
|
de.fakeWGAddr = netaddr.IPPortFrom(netaddr.IPFrom16(addr), 12345)
|
|
}
|
|
|
|
// noteRecvActivity records receive activity on de, and invokes
|
|
// Conn.noteRecvActivity no more than once every 10s.
|
|
func (de *endpoint) noteRecvActivity() {
|
|
if de.c.noteRecvActivity == nil {
|
|
return
|
|
}
|
|
now := mono.Now()
|
|
elapsed := now.Sub(de.lastRecv.LoadAtomic())
|
|
if elapsed > 10*time.Second {
|
|
de.lastRecv.StoreAtomic(now)
|
|
de.c.noteRecvActivity(de.publicKey)
|
|
}
|
|
}
|
|
|
|
// String exists purely so wireguard-go internals can log.Printf("%v")
|
|
// its internal conn.Endpoints and we don't end up with data races
|
|
// from fmt (via log) reading mutex fields and such.
|
|
func (de *endpoint) String() string {
|
|
return fmt.Sprintf("magicsock.endpoint{%v, %v}", de.publicKey.ShortString(), de.discoShort)
|
|
}
|
|
|
|
func (de *endpoint) ClearSrc() {}
|
|
func (de *endpoint) SrcToString() string { panic("unused") } // unused by wireguard-go
|
|
func (de *endpoint) SrcIP() net.IP { panic("unused") } // unused by wireguard-go
|
|
func (de *endpoint) DstToString() string { return de.wgEndpoint }
|
|
func (de *endpoint) DstIP() net.IP { panic("unused") }
|
|
func (de *endpoint) DstToBytes() []byte { return packIPPort(de.fakeWGAddr) }
|
|
|
|
// canP2P reports whether this endpoint understands the disco protocol
|
|
// and is expected to speak it.
|
|
//
|
|
// As of 2021-08-25, only a few hundred pre-0.100 clients understand
|
|
// DERP but not disco, so this returns false very rarely.
|
|
func (de *endpoint) canP2P() bool {
|
|
return !de.discoKey.IsZero()
|
|
}
|
|
|
|
// addrForSendLocked returns the address(es) that should be used for
|
|
// sending the next packet. Zero, one, or both of UDP address and DERP
|
|
// addr may be non-zero.
|
|
//
|
|
// de.mu must be held.
|
|
func (de *endpoint) addrForSendLocked(now mono.Time) (udpAddr, derpAddr netaddr.IPPort) {
|
|
udpAddr = de.bestAddr.IPPort
|
|
if udpAddr.IsZero() || now.After(de.trustBestAddrUntil) {
|
|
// We had a bestAddr but it expired so send both to it
|
|
// and DERP.
|
|
derpAddr = de.derpAddr
|
|
}
|
|
return
|
|
}
|
|
|
|
// heartbeat is called every heartbeatInterval to keep the best UDP path alive,
|
|
// or kick off discovery of other paths.
|
|
func (de *endpoint) heartbeat() {
|
|
de.mu.Lock()
|
|
defer de.mu.Unlock()
|
|
|
|
de.heartBeatTimer = nil
|
|
|
|
if !de.canP2P() {
|
|
// Cannot form p2p connections, no heartbeating necessary.
|
|
return
|
|
}
|
|
|
|
if de.lastSend.IsZero() {
|
|
// Shouldn't happen.
|
|
return
|
|
}
|
|
|
|
if mono.Since(de.lastSend) > sessionActiveTimeout {
|
|
// Session's idle. Stop heartbeating.
|
|
de.c.logf("[v1] magicsock: disco: ending heartbeats for idle session to %v (%v)", de.publicKey.ShortString(), de.discoShort)
|
|
return
|
|
}
|
|
|
|
now := mono.Now()
|
|
udpAddr, _ := de.addrForSendLocked(now)
|
|
if !udpAddr.IsZero() {
|
|
// We have a preferred path. Ping that every 2 seconds.
|
|
de.startPingLocked(udpAddr, now, pingHeartbeat)
|
|
}
|
|
|
|
if de.wantFullPingLocked(now) {
|
|
de.sendPingsLocked(now, true)
|
|
}
|
|
|
|
de.heartBeatTimer = time.AfterFunc(heartbeatInterval, de.heartbeat)
|
|
}
|
|
|
|
// wantFullPingLocked reports whether we should ping to all our peers looking for
|
|
// a better path.
|
|
//
|
|
// de.mu must be held.
|
|
func (de *endpoint) wantFullPingLocked(now mono.Time) bool {
|
|
if runtime.GOOS == "js" {
|
|
return false
|
|
}
|
|
if !de.canP2P() {
|
|
return false
|
|
}
|
|
if de.bestAddr.IsZero() || de.lastFullPing.IsZero() {
|
|
return true
|
|
}
|
|
if now.After(de.trustBestAddrUntil) {
|
|
return true
|
|
}
|
|
if de.bestAddr.latency <= goodEnoughLatency {
|
|
return false
|
|
}
|
|
if now.Sub(de.lastFullPing) >= upgradeInterval {
|
|
return true
|
|
}
|
|
return false
|
|
}
|
|
|
|
func (de *endpoint) noteActiveLocked() {
|
|
de.lastSend = mono.Now()
|
|
if de.heartBeatTimer == nil && de.canP2P() {
|
|
de.heartBeatTimer = time.AfterFunc(heartbeatInterval, de.heartbeat)
|
|
}
|
|
}
|
|
|
|
// cliPing starts a ping for the "tailscale ping" command. res is value to call cb with,
|
|
// already partially filled.
|
|
func (de *endpoint) cliPing(res *ipnstate.PingResult, cb func(*ipnstate.PingResult)) {
|
|
de.mu.Lock()
|
|
defer de.mu.Unlock()
|
|
|
|
de.pendingCLIPings = append(de.pendingCLIPings, pendingCLIPing{res, cb})
|
|
|
|
now := mono.Now()
|
|
udpAddr, derpAddr := de.addrForSendLocked(now)
|
|
if !derpAddr.IsZero() {
|
|
de.startPingLocked(derpAddr, now, pingCLI)
|
|
}
|
|
if !udpAddr.IsZero() && now.Before(de.trustBestAddrUntil) {
|
|
// Already have an active session, so just ping the address we're using.
|
|
// Otherwise "tailscale ping" results to a node on the local network
|
|
// can look like they're bouncing between, say 10.0.0.0/9 and the peer's
|
|
// IPv6 address, both 1ms away, and it's random who replies first.
|
|
de.startPingLocked(udpAddr, now, pingCLI)
|
|
} else if de.canP2P() {
|
|
for ep := range de.endpointState {
|
|
de.startPingLocked(ep, now, pingCLI)
|
|
}
|
|
}
|
|
de.noteActiveLocked()
|
|
}
|
|
|
|
func (de *endpoint) send(b []byte) error {
|
|
now := mono.Now()
|
|
|
|
de.mu.Lock()
|
|
udpAddr, derpAddr := de.addrForSendLocked(now)
|
|
if de.canP2P() && (udpAddr.IsZero() || now.After(de.trustBestAddrUntil)) {
|
|
de.sendPingsLocked(now, true)
|
|
}
|
|
de.noteActiveLocked()
|
|
de.mu.Unlock()
|
|
|
|
if udpAddr.IsZero() && derpAddr.IsZero() {
|
|
return errors.New("no UDP or DERP addr")
|
|
}
|
|
var err error
|
|
if !udpAddr.IsZero() {
|
|
_, err = de.c.sendAddr(udpAddr, key.NodePublicFromRaw32(mem.B(de.publicKey[:])), b)
|
|
}
|
|
if !derpAddr.IsZero() {
|
|
if ok, _ := de.c.sendAddr(derpAddr, key.NodePublicFromRaw32(mem.B(de.publicKey[:])), b); ok && err != nil {
|
|
// UDP failed but DERP worked, so good enough:
|
|
return nil
|
|
}
|
|
}
|
|
return err
|
|
}
|
|
|
|
func (de *endpoint) pingTimeout(txid stun.TxID) {
|
|
de.mu.Lock()
|
|
defer de.mu.Unlock()
|
|
sp, ok := de.sentPing[txid]
|
|
if !ok {
|
|
return
|
|
}
|
|
if debugDisco || de.bestAddr.IsZero() || mono.Now().After(de.trustBestAddrUntil) {
|
|
de.c.logf("[v1] magicsock: disco: timeout waiting for pong %x from %v (%v, %v)", txid[:6], sp.to, de.publicKey.ShortString(), de.discoShort)
|
|
}
|
|
de.removeSentPingLocked(txid, sp)
|
|
}
|
|
|
|
// forgetPing is called by a timer when a ping either fails to send or
|
|
// has taken too long to get a pong reply.
|
|
func (de *endpoint) forgetPing(txid stun.TxID) {
|
|
de.mu.Lock()
|
|
defer de.mu.Unlock()
|
|
if sp, ok := de.sentPing[txid]; ok {
|
|
de.removeSentPingLocked(txid, sp)
|
|
}
|
|
}
|
|
|
|
func (de *endpoint) removeSentPingLocked(txid stun.TxID, sp sentPing) {
|
|
// Stop the timer for the case where sendPing failed to write to UDP.
|
|
// In the case of a timer already having fired, this is a no-op:
|
|
sp.timer.Stop()
|
|
delete(de.sentPing, txid)
|
|
}
|
|
|
|
// sendDiscoPing sends a ping with the provided txid to ep.
|
|
//
|
|
// The caller (startPingLocked) should've already been recorded the ping in
|
|
// sentPing and set up the timer.
|
|
func (de *endpoint) sendDiscoPing(ep netaddr.IPPort, txid stun.TxID, logLevel discoLogLevel) {
|
|
selfPubKey, _ := de.c.publicKeyAtomic.Load().(tailcfg.NodeKey)
|
|
sent, _ := de.sendDiscoMessage(ep, &disco.Ping{
|
|
TxID: [12]byte(txid),
|
|
NodeKey: selfPubKey,
|
|
}, logLevel)
|
|
if !sent {
|
|
de.forgetPing(txid)
|
|
}
|
|
}
|
|
|
|
// discoPingPurpose is the reason why a discovery ping message was sent.
|
|
type discoPingPurpose int
|
|
|
|
//go:generate go run tailscale.com/cmd/addlicense -year 2020 -file discopingpurpose_string.go go run golang.org/x/tools/cmd/stringer -type=discoPingPurpose -trimprefix=ping
|
|
const (
|
|
// pingDiscovery means that purpose of a ping was to see if a
|
|
// path was valid.
|
|
pingDiscovery discoPingPurpose = iota
|
|
|
|
// pingHeartbeat means that purpose of a ping was whether a
|
|
// peer was still there.
|
|
pingHeartbeat
|
|
|
|
// pingCLI means that the user is running "tailscale ping"
|
|
// from the CLI. These types of pings can go over DERP.
|
|
pingCLI
|
|
)
|
|
|
|
func (de *endpoint) startPingLocked(ep netaddr.IPPort, now mono.Time, purpose discoPingPurpose) {
|
|
if !de.canP2P() {
|
|
panic("tried to disco ping a peer that can't disco")
|
|
}
|
|
if runtime.GOOS == "js" {
|
|
return
|
|
}
|
|
if purpose != pingCLI {
|
|
st, ok := de.endpointState[ep]
|
|
if !ok {
|
|
// Shouldn't happen. But don't ping an endpoint that's
|
|
// not active for us.
|
|
de.c.logf("magicsock: disco: [unexpected] attempt to ping no longer live endpoint %v", ep)
|
|
return
|
|
}
|
|
st.lastPing = now
|
|
}
|
|
|
|
txid := stun.NewTxID()
|
|
de.sentPing[txid] = sentPing{
|
|
to: ep,
|
|
at: now,
|
|
timer: time.AfterFunc(pingTimeoutDuration, func() { de.pingTimeout(txid) }),
|
|
purpose: purpose,
|
|
}
|
|
logLevel := discoLog
|
|
if purpose == pingHeartbeat {
|
|
logLevel = discoVerboseLog
|
|
}
|
|
go de.sendDiscoPing(ep, txid, logLevel)
|
|
}
|
|
|
|
func (de *endpoint) sendPingsLocked(now mono.Time, sendCallMeMaybe bool) {
|
|
de.lastFullPing = now
|
|
var sentAny bool
|
|
for ep, st := range de.endpointState {
|
|
if st.shouldDeleteLocked() {
|
|
de.deleteEndpointLocked(ep)
|
|
continue
|
|
}
|
|
if runtime.GOOS == "js" {
|
|
continue
|
|
}
|
|
if !st.lastPing.IsZero() && now.Sub(st.lastPing) < discoPingInterval {
|
|
continue
|
|
}
|
|
|
|
firstPing := !sentAny
|
|
sentAny = true
|
|
|
|
if firstPing && sendCallMeMaybe {
|
|
de.c.logf("[v1] magicsock: disco: send, starting discovery for %v (%v)", de.publicKey.ShortString(), de.discoShort)
|
|
}
|
|
|
|
de.startPingLocked(ep, now, pingDiscovery)
|
|
}
|
|
derpAddr := de.derpAddr
|
|
if sentAny && sendCallMeMaybe && !derpAddr.IsZero() {
|
|
// Have our magicsock.Conn figure out its STUN endpoint (if
|
|
// it doesn't know already) and then send a CallMeMaybe
|
|
// message to our peer via DERP informing them that we've
|
|
// sent so our firewall ports are probably open and now
|
|
// would be a good time for them to connect.
|
|
go de.c.enqueueCallMeMaybe(derpAddr, de)
|
|
}
|
|
}
|
|
|
|
func (de *endpoint) sendDiscoMessage(dst netaddr.IPPort, dm disco.Message, logLevel discoLogLevel) (sent bool, err error) {
|
|
return de.c.sendDiscoMessage(dst, de.publicKey, de.discoKey, dm, logLevel)
|
|
}
|
|
|
|
func (de *endpoint) updateFromNode(n *tailcfg.Node) {
|
|
if n == nil {
|
|
panic("nil node when updating disco ep")
|
|
}
|
|
de.mu.Lock()
|
|
defer de.mu.Unlock()
|
|
|
|
if de.discoKey != n.DiscoKey {
|
|
de.c.logf("[v1] magicsock: disco: node %s changed from discokey %s to %s", de.publicKey.ShortString(), de.discoKey, n.DiscoKey)
|
|
de.discoKey = n.DiscoKey
|
|
de.discoShort = de.discoKey.ShortString()
|
|
de.resetLocked()
|
|
}
|
|
if n.DERP == "" {
|
|
de.derpAddr = netaddr.IPPort{}
|
|
} else {
|
|
de.derpAddr, _ = netaddr.ParseIPPort(n.DERP)
|
|
}
|
|
|
|
for _, st := range de.endpointState {
|
|
st.index = indexSentinelDeleted // assume deleted until updated in next loop
|
|
}
|
|
for i, epStr := range n.Endpoints {
|
|
if i > math.MaxInt16 {
|
|
// Seems unlikely.
|
|
continue
|
|
}
|
|
ipp, err := netaddr.ParseIPPort(epStr)
|
|
if err != nil {
|
|
de.c.logf("magicsock: bogus netmap endpoint %q", epStr)
|
|
continue
|
|
}
|
|
if st, ok := de.endpointState[ipp]; ok {
|
|
st.index = int16(i)
|
|
} else {
|
|
de.endpointState[ipp] = &endpointState{index: int16(i)}
|
|
}
|
|
}
|
|
|
|
// Now delete anything unless it's still in the network map or
|
|
// was a recently discovered endpoint.
|
|
for ep, st := range de.endpointState {
|
|
if st.shouldDeleteLocked() {
|
|
de.deleteEndpointLocked(ep)
|
|
}
|
|
}
|
|
}
|
|
|
|
// addCandidateEndpoint adds ep as an endpoint to which we should send
|
|
// future pings.
|
|
//
|
|
// This is called once we've already verified that we got a valid
|
|
// discovery message from de via ep.
|
|
func (de *endpoint) addCandidateEndpoint(ep netaddr.IPPort) {
|
|
de.mu.Lock()
|
|
defer de.mu.Unlock()
|
|
|
|
if st, ok := de.endpointState[ep]; ok {
|
|
if st.lastGotPing.IsZero() {
|
|
// Already-known endpoint from the network map.
|
|
return
|
|
}
|
|
st.lastGotPing = time.Now()
|
|
return
|
|
}
|
|
|
|
// Newly discovered endpoint. Exciting!
|
|
de.c.logf("[v1] magicsock: disco: adding %v as candidate endpoint for %v (%s)", ep, de.discoShort, de.publicKey.ShortString())
|
|
de.endpointState[ep] = &endpointState{
|
|
lastGotPing: time.Now(),
|
|
}
|
|
|
|
// If for some reason this gets very large, do some cleanup.
|
|
if size := len(de.endpointState); size > 100 {
|
|
for ep, st := range de.endpointState {
|
|
if st.shouldDeleteLocked() {
|
|
de.deleteEndpointLocked(ep)
|
|
}
|
|
}
|
|
size2 := len(de.endpointState)
|
|
de.c.logf("[v1] magicsock: disco: addCandidateEndpoint pruned %v candidate set from %v to %v entries", size, size2)
|
|
}
|
|
}
|
|
|
|
// noteConnectivityChange is called when connectivity changes enough
|
|
// that we should question our earlier assumptions about which paths
|
|
// work.
|
|
func (de *endpoint) noteConnectivityChange() {
|
|
de.mu.Lock()
|
|
defer de.mu.Unlock()
|
|
|
|
de.trustBestAddrUntil = 0
|
|
}
|
|
|
|
// handlePongConnLocked handles a Pong message (a reply to an earlier ping).
|
|
// It should be called with the Conn.mu held.
|
|
//
|
|
// It reports whether m.TxID corresponds to a ping that this endpoint sent.
|
|
func (de *endpoint) handlePongConnLocked(m *disco.Pong, di *discoInfo, src netaddr.IPPort) (knownTxID bool) {
|
|
de.mu.Lock()
|
|
defer de.mu.Unlock()
|
|
|
|
isDerp := src.IP() == derpMagicIPAddr
|
|
|
|
sp, ok := de.sentPing[m.TxID]
|
|
if !ok {
|
|
// This is not a pong for a ping we sent.
|
|
return false
|
|
}
|
|
knownTxID = true // for naked returns below
|
|
de.removeSentPingLocked(m.TxID, sp)
|
|
di.setNodeKey(de.publicKey)
|
|
|
|
now := mono.Now()
|
|
latency := now.Sub(sp.at)
|
|
|
|
if !isDerp {
|
|
st, ok := de.endpointState[sp.to]
|
|
if !ok {
|
|
// This is no longer an endpoint we care about.
|
|
return
|
|
}
|
|
|
|
de.c.peerMap.setNodeKeyForIPPort(src, de.publicKey)
|
|
|
|
st.addPongReplyLocked(pongReply{
|
|
latency: latency,
|
|
pongAt: now,
|
|
from: src,
|
|
pongSrc: m.Src,
|
|
})
|
|
}
|
|
|
|
if sp.purpose != pingHeartbeat {
|
|
de.c.logf("[v1] magicsock: disco: %v<-%v (%v, %v) got pong tx=%x latency=%v pong.src=%v%v", de.c.discoShort, de.discoShort, de.publicKey.ShortString(), src, m.TxID[:6], latency.Round(time.Millisecond), m.Src, logger.ArgWriter(func(bw *bufio.Writer) {
|
|
if sp.to != src {
|
|
fmt.Fprintf(bw, " ping.to=%v", sp.to)
|
|
}
|
|
}))
|
|
}
|
|
|
|
for _, pp := range de.pendingCLIPings {
|
|
de.c.populateCLIPingResponseLocked(pp.res, latency, sp.to)
|
|
go pp.cb(pp.res)
|
|
}
|
|
de.pendingCLIPings = nil
|
|
|
|
// Promote this pong response to our current best address if it's lower latency.
|
|
// TODO(bradfitz): decide how latency vs. preference order affects decision
|
|
if !isDerp {
|
|
thisPong := addrLatency{sp.to, latency}
|
|
if betterAddr(thisPong, de.bestAddr) {
|
|
de.c.logf("magicsock: disco: node %v %v now using %v", de.publicKey.ShortString(), de.discoShort, sp.to)
|
|
de.bestAddr = thisPong
|
|
}
|
|
if de.bestAddr.IPPort == thisPong.IPPort {
|
|
de.bestAddr.latency = latency
|
|
de.bestAddrAt = now
|
|
de.trustBestAddrUntil = now.Add(trustUDPAddrDuration)
|
|
}
|
|
}
|
|
return
|
|
}
|
|
|
|
// addrLatency is an IPPort with an associated latency.
|
|
type addrLatency struct {
|
|
netaddr.IPPort
|
|
latency time.Duration
|
|
}
|
|
|
|
// betterAddr reports whether a is a better addr to use than b.
|
|
func betterAddr(a, b addrLatency) bool {
|
|
if a.IPPort == b.IPPort {
|
|
return false
|
|
}
|
|
if b.IsZero() {
|
|
return true
|
|
}
|
|
if a.IsZero() {
|
|
return false
|
|
}
|
|
if a.IP().Is6() && b.IP().Is4() {
|
|
// Prefer IPv6 for being a bit more robust, as long as
|
|
// the latencies are roughly equivalent.
|
|
if a.latency/10*9 < b.latency {
|
|
return true
|
|
}
|
|
} else if a.IP().Is4() && b.IP().Is6() {
|
|
if betterAddr(b, a) {
|
|
return false
|
|
}
|
|
}
|
|
return a.latency < b.latency
|
|
}
|
|
|
|
// endpoint.mu must be held.
|
|
func (st *endpointState) addPongReplyLocked(r pongReply) {
|
|
if n := len(st.recentPongs); n < pongHistoryCount {
|
|
st.recentPong = uint16(n)
|
|
st.recentPongs = append(st.recentPongs, r)
|
|
return
|
|
}
|
|
i := st.recentPong + 1
|
|
if i == pongHistoryCount {
|
|
i = 0
|
|
}
|
|
st.recentPongs[i] = r
|
|
st.recentPong = i
|
|
}
|
|
|
|
// handleCallMeMaybe handles a CallMeMaybe discovery message via
|
|
// DERP. The contract for use of this message is that the peer has
|
|
// already sent to us via UDP, so their stateful firewall should be
|
|
// open. Now we can Ping back and make it through.
|
|
func (de *endpoint) handleCallMeMaybe(m *disco.CallMeMaybe) {
|
|
if !de.canP2P() {
|
|
// How did we receive a disco message from a peer that can't disco?
|
|
panic("got call-me-maybe from peer with no discokey")
|
|
}
|
|
if runtime.GOOS == "js" {
|
|
// Nothing to do on js/wasm if we can't send UDP packets anyway.
|
|
return
|
|
}
|
|
de.mu.Lock()
|
|
defer de.mu.Unlock()
|
|
|
|
now := time.Now()
|
|
for ep := range de.isCallMeMaybeEP {
|
|
de.isCallMeMaybeEP[ep] = false // mark for deletion
|
|
}
|
|
if de.isCallMeMaybeEP == nil {
|
|
de.isCallMeMaybeEP = map[netaddr.IPPort]bool{}
|
|
}
|
|
var newEPs []netaddr.IPPort
|
|
for _, ep := range m.MyNumber {
|
|
if ep.IP().Is6() && ep.IP().IsLinkLocalUnicast() {
|
|
// We send these out, but ignore them for now.
|
|
// TODO: teach the ping code to ping on all interfaces
|
|
// for these.
|
|
continue
|
|
}
|
|
de.isCallMeMaybeEP[ep] = true
|
|
if es, ok := de.endpointState[ep]; ok {
|
|
es.callMeMaybeTime = now
|
|
} else {
|
|
de.endpointState[ep] = &endpointState{callMeMaybeTime: now}
|
|
newEPs = append(newEPs, ep)
|
|
}
|
|
}
|
|
if len(newEPs) > 0 {
|
|
de.c.logf("[v1] magicsock: disco: call-me-maybe from %v %v added new endpoints: %v",
|
|
de.publicKey.ShortString(), de.discoShort,
|
|
logger.ArgWriter(func(w *bufio.Writer) {
|
|
for i, ep := range newEPs {
|
|
if i > 0 {
|
|
w.WriteString(", ")
|
|
}
|
|
w.WriteString(ep.String())
|
|
}
|
|
}))
|
|
}
|
|
|
|
// Delete any prior CalllMeMaybe endpoints that weren't included
|
|
// in this message.
|
|
for ep, want := range de.isCallMeMaybeEP {
|
|
if !want {
|
|
delete(de.isCallMeMaybeEP, ep)
|
|
de.deleteEndpointLocked(ep)
|
|
}
|
|
}
|
|
|
|
// Zero out all the lastPing times to force sendPingsLocked to send new ones,
|
|
// even if it's been less than 5 seconds ago.
|
|
for _, st := range de.endpointState {
|
|
st.lastPing = 0
|
|
}
|
|
de.sendPingsLocked(mono.Now(), false)
|
|
}
|
|
|
|
func (de *endpoint) populatePeerStatus(ps *ipnstate.PeerStatus) {
|
|
de.mu.Lock()
|
|
defer de.mu.Unlock()
|
|
|
|
ps.Relay = de.c.derpRegionCodeOfIDLocked(int(de.derpAddr.Port()))
|
|
|
|
if de.lastSend.IsZero() {
|
|
return
|
|
}
|
|
|
|
now := mono.Now()
|
|
ps.LastWrite = de.lastSend.WallTime()
|
|
ps.Active = now.Sub(de.lastSend) < sessionActiveTimeout
|
|
|
|
if udpAddr, derpAddr := de.addrForSendLocked(now); !udpAddr.IsZero() && derpAddr.IsZero() {
|
|
ps.CurAddr = udpAddr.String()
|
|
}
|
|
}
|
|
|
|
// stopAndReset stops timers associated with de and resets its state back to zero.
|
|
// It's called when a discovery endpoint is no longer present in the
|
|
// NetworkMap, or when magicsock is transitioning from running to
|
|
// stopped state (via SetPrivateKey(zero))
|
|
func (de *endpoint) stopAndReset() {
|
|
atomic.AddInt64(&de.numStopAndResetAtomic, 1)
|
|
de.mu.Lock()
|
|
defer de.mu.Unlock()
|
|
|
|
de.c.logf("[v1] magicsock: doing cleanup for discovery key %x", de.discoKey[:])
|
|
|
|
de.resetLocked()
|
|
if de.heartBeatTimer != nil {
|
|
de.heartBeatTimer.Stop()
|
|
de.heartBeatTimer = nil
|
|
}
|
|
de.pendingCLIPings = nil
|
|
}
|
|
|
|
// resetLocked clears all the endpoint's p2p state, reverting it to a
|
|
// DERP-only endpoint. It does not stop the endpoint's heartbeat
|
|
// timer, if one is running.
|
|
func (de *endpoint) resetLocked() {
|
|
de.lastSend = 0
|
|
de.lastFullPing = 0
|
|
de.bestAddr = addrLatency{}
|
|
de.bestAddrAt = 0
|
|
de.trustBestAddrUntil = 0
|
|
for _, es := range de.endpointState {
|
|
es.lastPing = 0
|
|
}
|
|
for txid, sp := range de.sentPing {
|
|
de.removeSentPingLocked(txid, sp)
|
|
}
|
|
}
|
|
|
|
func (de *endpoint) numStopAndReset() int64 {
|
|
return atomic.LoadInt64(&de.numStopAndResetAtomic)
|
|
}
|
|
|
|
// derpStr replaces DERP IPs in s with "derp-".
|
|
func derpStr(s string) string { return strings.ReplaceAll(s, "127.3.3.40:", "derp-") }
|
|
|
|
// ippEndpointCache is a mutex-free single-element cache, mapping from
|
|
// a single netaddr.IPPort to a single endpoint.
|
|
type ippEndpointCache struct {
|
|
ipp netaddr.IPPort
|
|
gen int64
|
|
de *endpoint
|
|
}
|
|
|
|
// discoInfo is the info and state for the DiscoKey
|
|
// in the Conn.discoInfo map key.
|
|
//
|
|
// Note that a DiscoKey does not necessarily map to exactly one
|
|
// node. In the case of shared nodes and users switching accounts, two
|
|
// nodes in the NetMap may legitimately have the same DiscoKey. As
|
|
// such, no fields in here should be considered node-specific.
|
|
type discoInfo struct {
|
|
// discoKey is the same as the Conn.discoInfo map key,
|
|
// just so you can pass around a *discoInfo alone.
|
|
// Not modifed once initiazed.
|
|
discoKey tailcfg.DiscoKey
|
|
|
|
// discoShort is discoKey.ShortString().
|
|
// Not modifed once initiazed;
|
|
discoShort string
|
|
|
|
// sharedKey is the precomputed nacl/box key for
|
|
// communication with the peer that has the DiscoKey
|
|
// used to look up this *discoInfo in Conn.discoInfo.
|
|
// Not modifed once initialized.
|
|
sharedKey *[32]byte
|
|
|
|
// Mutable fields follow, owned by Conn.mu:
|
|
|
|
// lastPingFrom is the src of a ping for discoKey.
|
|
lastPingFrom netaddr.IPPort
|
|
|
|
// lastPingTime is the last time of a ping for discoKey.
|
|
lastPingTime time.Time
|
|
|
|
// lastNodeKey is the last NodeKey seen using discoKey.
|
|
// It's only updated if the NodeKey is unambiguous.
|
|
lastNodeKey tailcfg.NodeKey
|
|
|
|
// lastNodeKeyTime is the time a NodeKey was last seen using
|
|
// this discoKey. It's only updated if the NodeKey is
|
|
// unambiguous.
|
|
lastNodeKeyTime time.Time
|
|
}
|
|
|
|
// setNodeKey sets the most recent mapping from di.discoKey to the
|
|
// NodeKey nk.
|
|
func (di *discoInfo) setNodeKey(nk tailcfg.NodeKey) {
|
|
di.lastNodeKey = nk
|
|
di.lastNodeKeyTime = time.Now()
|
|
}
|