3770 lines
110 KiB
Go
3770 lines
110 KiB
Go
// Copyright (c) 2019 Tailscale Inc & AUTHORS All rights reserved.
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// Use of this source code is governed by a BSD-style
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// license that can be found in the LICENSE file.
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// Package magicsock implements a socket that can change its communication path while
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// in use, actively searching for the best way to communicate.
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package magicsock
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import (
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"bufio"
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"context"
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crand "crypto/rand"
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"encoding/binary"
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"errors"
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"expvar"
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"fmt"
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"hash/fnv"
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"math"
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"math/rand"
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"net"
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"os"
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"reflect"
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"sort"
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"strconv"
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"strings"
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"sync"
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"sync/atomic"
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"syscall"
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"time"
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"github.com/tailscale/wireguard-go/conn"
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"go4.org/mem"
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"golang.org/x/crypto/nacl/box"
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"golang.org/x/time/rate"
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"inet.af/netaddr"
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"tailscale.com/control/controlclient"
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"tailscale.com/derp"
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"tailscale.com/derp/derphttp"
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"tailscale.com/disco"
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"tailscale.com/ipn/ipnstate"
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"tailscale.com/logtail/backoff"
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"tailscale.com/net/dnscache"
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"tailscale.com/net/interfaces"
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"tailscale.com/net/netcheck"
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"tailscale.com/net/netns"
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"tailscale.com/net/portmapper"
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"tailscale.com/net/stun"
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"tailscale.com/syncs"
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"tailscale.com/tailcfg"
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"tailscale.com/tstime"
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"tailscale.com/types/key"
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"tailscale.com/types/logger"
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"tailscale.com/types/netmap"
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"tailscale.com/types/nettype"
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"tailscale.com/types/pad32"
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"tailscale.com/types/wgkey"
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"tailscale.com/version"
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"tailscale.com/wgengine/wgcfg"
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)
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// Various debugging and experimental tweakables, set by environment
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// variable.
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var (
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// logPacketDests prints the known addresses for a peer every time
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// they change, in the legacy (non-discovery) endpoint code only.
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logPacketDests, _ = strconv.ParseBool(os.Getenv("TS_DEBUG_LOG_PACKET_DESTS"))
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// debugDisco prints verbose logs of active discovery events as
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// they happen.
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debugDisco, _ = strconv.ParseBool(os.Getenv("TS_DEBUG_DISCO"))
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// debugOmitLocalAddresses removes all local interface addresses
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// from magicsock's discovered local endpoints. Used in some tests.
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debugOmitLocalAddresses, _ = strconv.ParseBool(os.Getenv("TS_DEBUG_OMIT_LOCAL_ADDRS"))
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// debugUseDerpRoute temporarily (2020-03-22) controls whether DERP
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// reverse routing is enabled (Issue 150). It will become always true
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// later.
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debugUseDerpRouteEnv = os.Getenv("TS_DEBUG_ENABLE_DERP_ROUTE")
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debugUseDerpRoute, _ = strconv.ParseBool(debugUseDerpRouteEnv)
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// logDerpVerbose logs all received DERP packets, including their
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// full payload.
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logDerpVerbose, _ = strconv.ParseBool(os.Getenv("TS_DEBUG_DERP"))
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// debugReSTUNStopOnIdle unconditionally enables the "shut down
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// STUN if magicsock is idle" behavior that normally only triggers
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// on mobile devices, lowers the shutdown interval, and logs more
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// verbosely about idle measurements.
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debugReSTUNStopOnIdle, _ = strconv.ParseBool(os.Getenv("TS_DEBUG_RESTUN_STOP_ON_IDLE"))
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)
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// useDerpRoute reports whether magicsock should enable the DERP
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// return path optimization (Issue 150).
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func useDerpRoute() bool {
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if debugUseDerpRouteEnv != "" {
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return debugUseDerpRoute
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}
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ob := controlclient.DERPRouteFlag()
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if v, ok := ob.Get(); ok {
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return v
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}
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return false
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}
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// inTest reports whether the running program is a test that set the
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// IN_TS_TEST environment variable.
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//
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// Unlike the other debug tweakables above, this one needs to be
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// checked every time at runtime, because tests set this after program
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// startup.
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func inTest() bool {
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inTest, _ := strconv.ParseBool(os.Getenv("IN_TS_TEST"))
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return inTest
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}
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// A Conn routes UDP packets and actively manages a list of its endpoints.
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// It implements wireguard/conn.Bind.
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type Conn struct {
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// This block mirrors the contents and field order of the Options
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// struct. Initialized once at construction, then constant.
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logf logger.Logf
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port uint16 // the preferred port from opts.Port; 0 means auto
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epFunc func(endpoints []string)
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derpActiveFunc func()
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idleFunc func() time.Duration // nil means unknown
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packetListener nettype.PacketListener
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noteRecvActivity func(tailcfg.DiscoKey) // or nil, see Options.NoteRecvActivity
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simulatedNetwork bool
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disableLegacy bool
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// ================================================================
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// No locking required to access these fields, either because
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// they're static after construction, or are wholly owned by a
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// single goroutine.
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connCtx context.Context // closed on Conn.Close
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connCtxCancel func() // closes connCtx
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donec <-chan struct{} // connCtx.Done()'s to avoid context.cancelCtx.Done()'s mutex per call
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// pconn4 and pconn6 are the underlying UDP sockets used to
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// send/receive packets for wireguard and other magicsock
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// protocols.
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pconn4 *RebindingUDPConn
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pconn6 *RebindingUDPConn
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// netChecker is the prober that discovers local network
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// conditions, including the closest DERP relay and NAT mappings.
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netChecker *netcheck.Client
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// portMapper is the NAT-PMP/PCP/UPnP prober/client, for requesting
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// port mappings from NAT devices.
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portMapper *portmapper.Client
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// sendLogLimit is a rate limiter for errors logged in the (hot)
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// packet sending codepath. It's so that, if magicsock gets into a
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// bad state, we don't spam one error per wireguard packet being
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// transmitted.
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// TODO(danderson): now that we have global rate-limiting, is this still useful?
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sendLogLimit *rate.Limiter
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// stunReceiveFunc holds the current STUN packet processing func.
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// Its Loaded value is always non-nil.
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stunReceiveFunc atomic.Value // of func(p []byte, fromAddr *net.UDPAddr)
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// derpRecvCh is used by ReceiveIPv4 to read DERP messages.
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derpRecvCh chan derpReadResult
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_ pad32.Four
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// derpRecvCountAtomic is how many derpRecvCh sends are pending.
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// It's incremented by runDerpReader whenever a DERP message
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// arrives and decremented when they're read.
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derpRecvCountAtomic int64
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// ippEndpoint4 and ippEndpoint6 are owned by ReceiveIPv4 and
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// ReceiveIPv6, respectively, to cache an IPPort->endpoint for
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// hot flows.
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ippEndpoint4, ippEndpoint6 ippEndpointCache
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// ============================================================
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mu sync.Mutex // guards all following fields; see userspaceEngine lock ordering rules
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muCond *sync.Cond
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started bool // Start was called
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closed bool // Close was called
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// derpCleanupTimer is the timer that fires to occasionally clean
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// up idle DERP connections. It's only used when there is a non-home
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// DERP connection in use.
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derpCleanupTimer *time.Timer
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// derpCleanupTimerArmed is whether derpCleanupTimer is
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// scheduled to fire within derpCleanStaleInterval.
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derpCleanupTimerArmed bool
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// periodicReSTUNTimer, when non-nil, is an AfterFunc timer
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// that will call Conn.doPeriodicSTUN.
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periodicReSTUNTimer *time.Timer
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// endpointsUpdateActive indicates that updateEndpoints is
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// currently running. It's used to deduplicate concurrent endpoint
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// update requests.
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endpointsUpdateActive bool
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// wantEndpointsUpdate, if non-empty, means that a new endpoints
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// update should begin immediately after the currently-running one
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// completes. It can only be non-empty if
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// endpointsUpdateActive==true.
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wantEndpointsUpdate string // true if non-empty; string is reason
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// lastEndpoints records the endpoints found during the previous
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// endpoint discovery. It's used to avoid duplicate endpoint
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// change notifications.
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lastEndpoints []string
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// lastEndpointsTime is the last time the endpoints were updated,
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// even if there was no change.
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lastEndpointsTime time.Time
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// onEndpointRefreshed are funcs to run (in their own goroutines)
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// when endpoints are refreshed.
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onEndpointRefreshed map[*discoEndpoint]func()
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// peerSet is the set of peers that are currently configured in
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// WireGuard. These are not used to filter inbound or outbound
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// traffic at all, but only to track what state can be cleaned up
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// in other maps below that are keyed by peer public key.
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peerSet map[key.Public]struct{}
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// discoPrivate is the private naclbox key used for active
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// discovery traffic. It's created once near (but not during)
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// construction.
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discoPrivate key.Private
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discoPublic tailcfg.DiscoKey // public of discoPrivate
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discoShort string // ShortString of discoPublic (to save logging work later)
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// nodeOfDisco tracks the networkmap Node entity for each peer
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// discovery key.
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//
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// TODO(danderson): the only thing we ever use from this is the
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// peer's WireGuard public key. This could be a map of DiscoKey to
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// NodeKey.
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nodeOfDisco map[tailcfg.DiscoKey]*tailcfg.Node
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discoOfNode map[tailcfg.NodeKey]tailcfg.DiscoKey
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discoOfAddr map[netaddr.IPPort]tailcfg.DiscoKey // validated non-DERP paths only
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// endpointsOfDisco tracks the wireguard-go endpoints for peers
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// with recent activity.
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endpointOfDisco map[tailcfg.DiscoKey]*discoEndpoint // those with activity only
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sharedDiscoKey map[tailcfg.DiscoKey]*[32]byte // nacl/box precomputed key
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// addrsByUDP is a map of every remote ip:port to a priority
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// list of endpoint addresses for a peer.
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// The priority list is provided by wgengine configuration.
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//
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// Given a wgcfg describing:
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// machineA: 10.0.0.1:1, 10.0.0.2:2
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// machineB: 10.0.0.3:3
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// the addrsByUDP map contains:
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// 10.0.0.1:1 -> [10.0.0.1:1, 10.0.0.2:2]
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// 10.0.0.2:2 -> [10.0.0.1:1, 10.0.0.2:2]
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// 10.0.0.3:3 -> [10.0.0.3:3]
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//
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// Used only to communicate with legacy, pre-active-discovery
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// clients.
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addrsByUDP map[netaddr.IPPort]*addrSet
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// addrsByKey maps from public keys (as seen by incoming DERP
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// packets) to its addrSet (the same values as in addrsByUDP).
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//
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// Used only to communicate with legacy, pre-active-discovery
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// clients.
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addrsByKey map[key.Public]*addrSet
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// netInfoFunc is a callback that provides a tailcfg.NetInfo when
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// discovered network conditions change.
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//
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// TODO(danderson): why can't it be set at construction time?
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// There seem to be a few natural places in ipn/local.go to
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// swallow untimely invocations.
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netInfoFunc func(*tailcfg.NetInfo) // nil until set
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// netInfoLast is the NetInfo provided in the last call to
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// netInfoFunc. It's used to deduplicate calls to netInfoFunc.
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//
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// TODO(danderson): should all the deduping happen in
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// ipn/local.go? We seem to be doing dedupe at several layers, and
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// magicsock could do with any complexity reduction it can get.
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netInfoLast *tailcfg.NetInfo
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derpMap *tailcfg.DERPMap // nil (or zero regions/nodes) means DERP is disabled
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netMap *netmap.NetworkMap
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privateKey key.Private // WireGuard private key for this node
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everHadKey bool // whether we ever had a non-zero private key
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myDerp int // nearest DERP region ID; 0 means none/unknown
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derpStarted chan struct{} // closed on first connection to DERP; for tests & cleaner Close
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activeDerp map[int]activeDerp // DERP regionID -> connection to a node in that region
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prevDerp map[int]*syncs.WaitGroupChan
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// derpRoute contains optional alternate routes to use as an
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// optimization instead of contacting a peer via their home
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// DERP connection. If they sent us a message on a different
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// DERP connection (which should really only be on our DERP
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// home connection, or what was once our home), then we
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// remember that route here to optimistically use instead of
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// creating a new DERP connection back to their home.
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derpRoute map[key.Public]derpRoute
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// peerLastDerp tracks which DERP node we last used to speak with a
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// peer. It's only used to quiet logging, so we only log on change.
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peerLastDerp map[key.Public]int
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// noV4 and noV6 are whether IPv4 and IPv6 are known to be
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// missing. They're only used to suppress log spam. The name
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// is named negatively because in early start-up, we don't yet
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// necessarily have a netcheck.Report and don't want to skip
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// logging.
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noV4, noV6 syncs.AtomicBool
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// networkUp is whether the network is up (some interface is up
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// with IPv4 or IPv6). It's used to suppress log spam and prevent
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// new connection that'll fail.
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networkUp syncs.AtomicBool
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// havePrivateKey is whether privateKey is non-zero.
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havePrivateKey syncs.AtomicBool
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}
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// derpRoute is a route entry for a public key, saying that a certain
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// peer should be available at DERP node derpID, as long as the
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// current connection for that derpID is dc. (but dc should not be
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// used to write directly; it's owned by the read/write loops)
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type derpRoute struct {
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derpID int
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dc *derphttp.Client // don't use directly; see comment above
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}
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// removeDerpPeerRoute removes a DERP route entry previously added by addDerpPeerRoute.
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func (c *Conn) removeDerpPeerRoute(peer key.Public, derpID int, dc *derphttp.Client) {
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c.mu.Lock()
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defer c.mu.Unlock()
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r2 := derpRoute{derpID, dc}
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if r, ok := c.derpRoute[peer]; ok && r == r2 {
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delete(c.derpRoute, peer)
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}
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}
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// addDerpPeerRoute adds a DERP route entry, noting that peer was seen
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// on DERP node derpID, at least on the connection identified by dc.
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// See issue 150 for details.
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func (c *Conn) addDerpPeerRoute(peer key.Public, derpID int, dc *derphttp.Client) {
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c.mu.Lock()
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defer c.mu.Unlock()
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if c.derpRoute == nil {
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c.derpRoute = make(map[key.Public]derpRoute)
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}
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r := derpRoute{derpID, dc}
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c.derpRoute[peer] = r
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}
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// DerpMagicIP is a fake WireGuard endpoint IP address that means
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// to use DERP. When used, the port number of the WireGuard endpoint
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// is the DERP server number to use.
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//
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// Mnemonic: 3.3.40 are numbers above the keys D, E, R, P.
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const DerpMagicIP = "127.3.3.40"
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var derpMagicIPAddr = netaddr.MustParseIP(DerpMagicIP)
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// activeDerp contains fields for an active DERP connection.
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type activeDerp struct {
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c *derphttp.Client
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cancel context.CancelFunc
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writeCh chan<- derpWriteRequest
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// lastWrite is the time of the last request for its write
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// channel (currently even if there was no write).
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// It is always non-nil and initialized to a non-zero Time.
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lastWrite *time.Time
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createTime time.Time
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}
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// DefaultPort is the default port to listen on.
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// The current default (zero) means to auto-select a random free port.
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const DefaultPort = 0
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// Options contains options for Listen.
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type Options struct {
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// Logf optionally provides a log function to use.
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// Must not be nil.
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Logf logger.Logf
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// Port is the port to listen on.
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// Zero means to pick one automatically.
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Port uint16
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// EndpointsFunc optionally provides a func to be called when
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// endpoints change. The called func does not own the slice.
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EndpointsFunc func(endpoint []string)
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// DERPActiveFunc optionally provides a func to be called when
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// a connection is made to a DERP server.
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DERPActiveFunc func()
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// IdleFunc optionally provides a func to return how long
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// it's been since a TUN packet was sent or received.
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IdleFunc func() time.Duration
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// PacketListener optionally specifies how to create PacketConns.
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// It's meant for testing.
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PacketListener nettype.PacketListener
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// NoteRecvActivity, if provided, is a func for magicsock to
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// call whenever it receives a packet from a a
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// discovery-capable peer if it's been more than ~10 seconds
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// since the last one. (10 seconds is somewhat arbitrary; the
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// sole user just doesn't need or want it called on every
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// packet, just every minute or two for Wireguard timeouts,
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// and 10 seconds seems like a good trade-off between often
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// enough and not too often.) The provided func is called
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// while holding userspaceEngine.wgLock and likely calls
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// Conn.CreateEndpoint, which acquires Conn.mu. As such, you
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// should not hold Conn.mu while calling it.
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NoteRecvActivity func(tailcfg.DiscoKey)
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// SimulatedNetwork can be set true in tests to signal that
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// the network is simulated and thus it's okay to bind on the
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// unspecified address (which we'd normally avoid to avoid
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// triggering macOS and Windows firwall dialog boxes during
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// "go test").
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SimulatedNetwork bool
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// DisableLegacyNetworking disables legacy peer handling. When
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// enabled, only active discovery-aware nodes will be able to
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// communicate with Conn.
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DisableLegacyNetworking bool
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}
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func (o *Options) logf() logger.Logf {
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if o.Logf == nil {
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panic("must provide magicsock.Options.logf")
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}
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return o.Logf
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}
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func (o *Options) endpointsFunc() func([]string) {
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if o == nil || o.EndpointsFunc == nil {
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return func([]string) {}
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}
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return o.EndpointsFunc
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}
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func (o *Options) derpActiveFunc() func() {
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if o == nil || o.DERPActiveFunc == nil {
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return func() {}
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}
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return o.DERPActiveFunc
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}
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// newConn is the error-free, network-listening-side-effect-free based
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// of NewConn. Mostly for tests.
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func newConn() *Conn {
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c := &Conn{
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disableLegacy: true,
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sendLogLimit: rate.NewLimiter(rate.Every(1*time.Minute), 1),
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addrsByUDP: make(map[netaddr.IPPort]*addrSet),
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addrsByKey: make(map[key.Public]*addrSet),
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derpRecvCh: make(chan derpReadResult),
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derpStarted: make(chan struct{}),
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peerLastDerp: make(map[key.Public]int),
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endpointOfDisco: make(map[tailcfg.DiscoKey]*discoEndpoint),
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sharedDiscoKey: make(map[tailcfg.DiscoKey]*[32]byte),
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discoOfAddr: make(map[netaddr.IPPort]tailcfg.DiscoKey),
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}
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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 = opts.Port
|
|
c.logf = opts.logf()
|
|
c.epFunc = opts.endpointsFunc()
|
|
c.derpActiveFunc = opts.derpActiveFunc()
|
|
c.idleFunc = opts.IdleFunc
|
|
c.packetListener = opts.PacketListener
|
|
c.noteRecvActivity = opts.NoteRecvActivity
|
|
c.simulatedNetwork = opts.SimulatedNetwork
|
|
c.disableLegacy = opts.DisableLegacyNetworking
|
|
c.portMapper = portmapper.NewClient(logger.WithPrefix(c.logf, "portmapper: "))
|
|
|
|
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
|
|
}
|
|
|
|
func (c *Conn) Start() {
|
|
c.mu.Lock()
|
|
if c.started {
|
|
panic("duplicate Start call")
|
|
}
|
|
c.started = true
|
|
c.mu.Unlock()
|
|
|
|
c.ReSTUN("initial")
|
|
}
|
|
|
|
// 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)
|
|
|
|
endpoints, reasons, 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, reasons) {
|
|
c.logEndpointChange(endpoints, reasons)
|
|
c.epFunc(endpoints)
|
|
}
|
|
}
|
|
|
|
// setEndpoints records the new endpoints, reporting whether they're changed.
|
|
// It takes ownership of the slice.
|
|
func (c *Conn) setEndpoints(endpoints []string, reasons map[string]string) (changed bool) {
|
|
anySTUN := false
|
|
for _, reason := range reasons {
|
|
if reason == "stun" {
|
|
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 stringsEqual(endpoints, c.lastEndpoints) {
|
|
return false
|
|
}
|
|
c.lastEndpoints = endpoints
|
|
return true
|
|
}
|
|
|
|
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)
|
|
|
|
ni := &tailcfg.NetInfo{
|
|
DERPLatency: map[string]float64{},
|
|
MappingVariesByDestIP: report.MappingVariesByDestIP,
|
|
HairPinning: report.HairPinning,
|
|
UPnP: report.UPnP,
|
|
PMP: report.PMP,
|
|
PCP: report.PCP,
|
|
}
|
|
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
|
|
}
|
|
|
|
// See where our peers are.
|
|
var (
|
|
peersOnDerp = map[int]int{}
|
|
best int
|
|
bestCount int
|
|
)
|
|
for _, as := range c.addrsByKey {
|
|
if id := as.derpID(); id != 0 {
|
|
peersOnDerp[id]++
|
|
if v := peersOnDerp[id]; v > bestCount {
|
|
bestCount = v
|
|
best = id
|
|
}
|
|
}
|
|
}
|
|
|
|
// If we already had selected something in the past and it has
|
|
// any peers, stay on it. If there are no peers, though, also
|
|
// stay where we are.
|
|
if c.myDerp != 0 && (best == 0 || peersOnDerp[c.myDerp] != 0) {
|
|
return c.myDerp
|
|
}
|
|
|
|
// Otherwise pick wherever the most peers are.
|
|
if best != 0 {
|
|
return best
|
|
}
|
|
|
|
// Otherwise just pick something randomly.
|
|
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.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(discoKey tailcfg.DiscoKey, addr netaddr.IPPort) {
|
|
c.mu.Lock()
|
|
defer c.mu.Unlock()
|
|
c.discoOfAddr[addr] = discoKey
|
|
}
|
|
|
|
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)
|
|
}
|
|
}
|
|
|
|
// peerForIP returns the Node in nm that's responsible for
|
|
// handling the given IP address.
|
|
func peerForIP(nm *netmap.NetworkMap, ip netaddr.IP) (n *tailcfg.Node, ok bool) {
|
|
if nm == nil {
|
|
return nil, false
|
|
}
|
|
// Check for exact matches before looking for subnet matches.
|
|
for _, p := range nm.Peers {
|
|
for _, a := range p.Addresses {
|
|
if a.IP == ip {
|
|
return p, true
|
|
}
|
|
}
|
|
}
|
|
|
|
// TODO(bradfitz): this is O(n peers). Add ART to netaddr?
|
|
var best netaddr.IPPrefix
|
|
for _, p := range nm.Peers {
|
|
for _, cidr := range p.AllowedIPs {
|
|
if cidr.Contains(ip) {
|
|
if best.IsZero() || cidr.Bits > best.Bits {
|
|
n = p
|
|
best = cidr
|
|
}
|
|
}
|
|
}
|
|
}
|
|
return n, n != nil
|
|
}
|
|
|
|
// PeerForIP returns the node that ip should route to.
|
|
func (c *Conn) PeerForIP(ip netaddr.IP) (n *tailcfg.Node, ok bool) {
|
|
c.mu.Lock()
|
|
defer c.mu.Unlock()
|
|
if c.netMap == nil {
|
|
return
|
|
}
|
|
return peerForIP(c.netMap, ip)
|
|
}
|
|
|
|
// LastRecvActivityOfDisco returns the time we last got traffic from
|
|
// this endpoint (updated every ~10 seconds).
|
|
func (c *Conn) LastRecvActivityOfDisco(dk tailcfg.DiscoKey) time.Time {
|
|
c.mu.Lock()
|
|
defer c.mu.Unlock()
|
|
de, ok := c.endpointOfDisco[dk]
|
|
if !ok {
|
|
return time.Time{}
|
|
}
|
|
unix := atomic.LoadInt64(&de.lastRecvUnixAtomic)
|
|
if unix == 0 {
|
|
return time.Time{}
|
|
}
|
|
return time.Unix(unix, 0)
|
|
}
|
|
|
|
// Ping handles a "tailscale ping" CLI query.
|
|
func (c *Conn) Ping(ip netaddr.IP, cb func(*ipnstate.PingResult)) {
|
|
c.mu.Lock()
|
|
defer c.mu.Unlock()
|
|
res := &ipnstate.PingResult{IP: ip.String()}
|
|
if c.privateKey.IsZero() {
|
|
res.Err = "local tailscaled stopped"
|
|
cb(res)
|
|
return
|
|
}
|
|
peer, ok := peerForIP(c.netMap, ip)
|
|
if !ok {
|
|
res.Err = "no matching peer"
|
|
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]
|
|
}
|
|
}
|
|
|
|
dk, ok := c.discoOfNode[peer.Key]
|
|
if !ok { // peer is using outdated Tailscale version (pre-0.100)
|
|
res.Err = "no discovery key for peer (pre Tailscale 0.100 version?). Try: ping 100.x.y.z"
|
|
cb(res)
|
|
return
|
|
}
|
|
de, ok := c.endpointOfDisco[dk]
|
|
if !ok {
|
|
c.mu.Unlock() // temporarily release
|
|
if c.noteRecvActivity != nil {
|
|
c.noteRecvActivity(dk)
|
|
}
|
|
c.mu.Lock() // re-acquire
|
|
|
|
// re-check at least basic invariant:
|
|
if c.privateKey.IsZero() {
|
|
res.Err = "local tailscaled stopped"
|
|
cb(res)
|
|
return
|
|
}
|
|
|
|
de, ok = c.endpointOfDisco[dk]
|
|
if !ok {
|
|
res.Err = "internal error: failed to create endpoint for discokey"
|
|
cb(res)
|
|
return
|
|
}
|
|
c.logf("[v1] magicsock: started peer %v for ping to %v", dk.ShortString(), peer.Key.ShortString())
|
|
}
|
|
de.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
|
|
if c.derpMap != nil {
|
|
if dr, ok := c.derpMap.Regions[regionID]; ok {
|
|
res.DERPRegionCode = dr.RegionCode
|
|
}
|
|
}
|
|
}
|
|
|
|
// 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()
|
|
_, ok := c.discoOfNode[k]
|
|
return ok
|
|
}
|
|
|
|
// 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
|
|
return false
|
|
}
|
|
if derpNum == c.myDerp {
|
|
// No change.
|
|
return true
|
|
}
|
|
c.myDerp = 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.IPPort{IP: derpMagicIPAddr, Port: uint16(node)}, key.Public{})
|
|
}
|
|
|
|
// 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) (ipPorts []string, reasons map[string]string, err error) {
|
|
nr, err := c.updateNetInfo(ctx)
|
|
if err != nil {
|
|
c.logf("magicsock.Conn.determineEndpoints: updateNetInfo: %v", err)
|
|
return nil, nil, err
|
|
}
|
|
|
|
already := make(map[string]string) // endpoint -> how it was found
|
|
var eps []string // unique endpoints
|
|
|
|
addAddr := func(s, reason string) {
|
|
if debugOmitLocalAddresses && (reason == "localAddresses" || reason == "socket") {
|
|
return
|
|
}
|
|
if _, ok := already[s]; !ok {
|
|
already[s] = reason
|
|
eps = append(eps, s)
|
|
}
|
|
}
|
|
|
|
if ext, err := c.portMapper.CreateOrGetMapping(ctx); err == nil {
|
|
c.logf("portmapper: using %v", ext)
|
|
addAddr(ext.String(), "portmap")
|
|
} else if !portmapper.IsNoMappingError(err) {
|
|
c.logf("portmapper: %v", err)
|
|
}
|
|
|
|
if nr.GlobalV4 != "" {
|
|
addAddr(nr.GlobalV4, "stun")
|
|
|
|
// 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 nr.MappingVariesByDestIP.EqualBool(true) && c.port != 0 {
|
|
if ip, _, err := net.SplitHostPort(nr.GlobalV4); err == nil {
|
|
addAddr(net.JoinHostPort(ip, strconv.Itoa(int(c.port))), "port_in")
|
|
}
|
|
}
|
|
}
|
|
if nr.GlobalV6 != "" {
|
|
addAddr(nr.GlobalV6, "stun")
|
|
}
|
|
|
|
c.ignoreSTUNPackets()
|
|
|
|
if localAddr := c.pconn4.LocalAddr(); localAddr.IP.IsUnspecified() {
|
|
ips, loopback, err := interfaces.LocalAddresses()
|
|
if err != nil {
|
|
return nil, nil, err
|
|
}
|
|
reason := "localAddresses"
|
|
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
|
|
reason = "loopback"
|
|
}
|
|
for _, ipStr := range ips {
|
|
addAddr(net.JoinHostPort(ipStr, fmt.Sprint(localAddr.Port)), reason)
|
|
}
|
|
} else {
|
|
// Our local endpoint is bound to a particular address.
|
|
// Do not offer addresses on other local interfaces.
|
|
addAddr(localAddr.String(), "socket")
|
|
}
|
|
|
|
// 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).
|
|
return eps, already, nil
|
|
}
|
|
|
|
func stringsEqual(x, y []string) bool {
|
|
if len(x) != len(y) {
|
|
return false
|
|
}
|
|
for i := range x {
|
|
if x[i] != y[i] {
|
|
return false
|
|
}
|
|
}
|
|
return true
|
|
}
|
|
|
|
// LocalPort returns the current IPv4 listener's port number.
|
|
func (c *Conn) LocalPort() uint16 {
|
|
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
|
|
}
|
|
|
|
switch v := ep.(type) {
|
|
default:
|
|
panic(fmt.Sprintf("[unexpected] Endpoint type %T", v))
|
|
case *discoEndpoint:
|
|
return v.send(b)
|
|
case *addrSet:
|
|
return c.sendAddrSet(b, v)
|
|
}
|
|
}
|
|
|
|
var errConnClosed = errors.New("Conn closed")
|
|
|
|
var errDropDerpPacket = errors.New("too many DERP packets queued; dropping")
|
|
|
|
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) {
|
|
ua := udpAddrPool.Get().(*net.UDPAddr)
|
|
defer udpAddrPool.Put(ua)
|
|
return c.sendUDPStd(ipp.UDPAddrAt(ua), b)
|
|
}
|
|
|
|
// 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.Public, 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.Public) 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 = peerShort(peer)
|
|
}
|
|
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.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.Public, 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)", peerShort(peer), regionID, newDesc)
|
|
} else {
|
|
c.logf("[v1] magicsock: derp route for %s changed from derp-%d => derp-%d (%s)", peerShort(peer), 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.Public // may be zero until server deployment if v2+
|
|
// 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
|
|
}
|
|
|
|
// 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.Public]bool{}
|
|
bo := backoff.NewBackoff(fmt.Sprintf("derp-%d", regionID), c.logf, 5*time.Second)
|
|
for {
|
|
msg, err := dc.Recv()
|
|
if err != nil {
|
|
// 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
|
|
|
|
switch m := msg.(type) {
|
|
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[m.Source]; !ok {
|
|
peerPresent[m.Source] = true
|
|
c.addDerpPeerRoute(m.Source, regionID, dc)
|
|
}
|
|
default:
|
|
// Ignore.
|
|
continue
|
|
}
|
|
|
|
if !c.sendDerpReadResult(ctx, res) {
|
|
return
|
|
}
|
|
select {
|
|
case <-ctx.Done():
|
|
return
|
|
case <-didCopy:
|
|
continue
|
|
}
|
|
}
|
|
}
|
|
|
|
var (
|
|
testCounterZeroDerpReadResultSend expvar.Int
|
|
testCounterZeroDerpReadResultRecv expvar.Int
|
|
)
|
|
|
|
// sendDerpReadResult sends res to c.derpRecvCh and reports whether it
|
|
// was sent. (It reports false if ctx was done first.)
|
|
//
|
|
// This includes doing the whole wake-up dance to interrupt
|
|
// ReceiveIPv4's blocking UDP read.
|
|
func (c *Conn) sendDerpReadResult(ctx context.Context, res derpReadResult) (sent bool) {
|
|
// Before we wake up ReceiveIPv4 with SetReadDeadline,
|
|
// note that a DERP packet has arrived. ReceiveIPv4
|
|
// will read this field to note that its UDP read
|
|
// error is due to us.
|
|
atomic.AddInt64(&c.derpRecvCountAtomic, 1)
|
|
// Cancel the pconn read goroutine.
|
|
c.pconn4.SetReadDeadline(aLongTimeAgo)
|
|
select {
|
|
case <-ctx.Done():
|
|
select {
|
|
case <-c.donec:
|
|
// The whole Conn shut down. The reader of
|
|
// c.derpRecvCh also selects on c.donec, so it's
|
|
// safe to abort now.
|
|
case c.derpRecvCh <- (derpReadResult{}):
|
|
// Just this DERP reader is closing (perhaps
|
|
// the user is logging out, or the DERP
|
|
// connection is too idle for sends). Since we
|
|
// already incremented c.derpRecvCountAtomic,
|
|
// we need to send on the channel (unless the
|
|
// conn is going down).
|
|
// The receiver treats a derpReadResult zero value
|
|
// message as a skip.
|
|
testCounterZeroDerpReadResultSend.Add(1)
|
|
|
|
}
|
|
return false
|
|
case c.derpRecvCh <- res:
|
|
return true
|
|
}
|
|
}
|
|
|
|
type derpWriteRequest struct {
|
|
addr netaddr.IPPort
|
|
pubKey key.Public
|
|
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)
|
|
}
|
|
}
|
|
}
|
|
}
|
|
|
|
// findEndpoint maps from a UDP address to a WireGuard endpoint, for
|
|
// ReceiveIPv4/ReceiveIPv6.
|
|
//
|
|
// TODO(bradfitz): add a fast path that returns nil here for normal
|
|
// wireguard-go transport packets; wireguard-go only uses this
|
|
// Endpoint for the relatively rare non-data packets; but we need the
|
|
// Endpoint to find the UDPAddr to return to wireguard anyway, so no
|
|
// benefit unless we can, say, always return the same fake UDPAddr for
|
|
// all packets.
|
|
func (c *Conn) findEndpoint(ipp netaddr.IPPort, packet []byte) conn.Endpoint {
|
|
c.mu.Lock()
|
|
defer c.mu.Unlock()
|
|
|
|
// See if they have a discoEndpoint, for a set of peers
|
|
// both supporting active discovery.
|
|
if dk, ok := c.discoOfAddr[ipp]; ok {
|
|
if ep, ok := c.endpointOfDisco[dk]; ok {
|
|
return ep
|
|
}
|
|
}
|
|
|
|
return c.findLegacyEndpointLocked(ipp, packet)
|
|
}
|
|
|
|
// aLongTimeAgo is a non-zero time, far in the past, used for
|
|
// immediate cancellation of network operations.
|
|
var aLongTimeAgo = time.Unix(233431200, 0)
|
|
|
|
// noteRecvActivityFromEndpoint calls the c.noteRecvActivity hook if
|
|
// e is a discovery-capable peer and this is the first receive activity
|
|
// it's got in awhile (in last 10 seconds).
|
|
//
|
|
// This should be called whenever a packet arrives from e.
|
|
func (c *Conn) noteRecvActivityFromEndpoint(e conn.Endpoint) {
|
|
de, ok := e.(*discoEndpoint)
|
|
if ok && c.noteRecvActivity != nil && de.isFirstRecvActivityInAwhile() {
|
|
c.noteRecvActivity(de.discoKey)
|
|
}
|
|
}
|
|
|
|
func (c *Conn) ReceiveIPv6(b []byte) (int, conn.Endpoint, error) {
|
|
if c.pconn6 == nil {
|
|
return 0, nil, syscall.EAFNOSUPPORT
|
|
}
|
|
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
|
|
}
|
|
}
|
|
}
|
|
|
|
func (c *Conn) derpPacketArrived() bool {
|
|
return atomic.LoadInt64(&c.derpRecvCountAtomic) > 0
|
|
}
|
|
|
|
// ReceiveIPv4 is called by wireguard-go to receive an IPv4 packet.
|
|
// In Tailscale's case, that packet might also arrive via DERP. A DERP packet arrival
|
|
// aborts the pconn4 read deadline to make it fail.
|
|
func (c *Conn) ReceiveIPv4(b []byte) (n int, ep conn.Endpoint, err error) {
|
|
var ipp netaddr.IPPort
|
|
for {
|
|
// Drain DERP queues before reading new UDP packets.
|
|
if c.derpPacketArrived() {
|
|
goto ReadDERP
|
|
}
|
|
n, ipp, err = c.pconn4.ReadFromNetaddr(b)
|
|
if err != nil {
|
|
// If the pconn4 read failed, the likely reason is a DERP reader received
|
|
// a packet and interrupted us.
|
|
// It's possible for ReadFrom to return a non deadline exceeded error
|
|
// and for there to have also had a DERP packet arrive, but that's fine:
|
|
// we'll get the same error from ReadFrom later.
|
|
if c.derpPacketArrived() {
|
|
goto ReadDERP
|
|
}
|
|
return 0, nil, err
|
|
}
|
|
if ep, ok := c.receiveIP(b[:n], ipp, &c.ippEndpoint4); ok {
|
|
return n, ep, nil
|
|
} else {
|
|
continue
|
|
}
|
|
ReadDERP:
|
|
n, ep, err = c.receiveIPv4DERP(b)
|
|
if err == errLoopAgain {
|
|
continue
|
|
}
|
|
return n, ep, err
|
|
}
|
|
}
|
|
|
|
// 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 conn.Endpoint, ok bool) {
|
|
if stun.Is(b) {
|
|
c.stunReceiveFunc.Load().(func([]byte, netaddr.IPPort))(b, ipp)
|
|
return nil, false
|
|
}
|
|
if c.handleDiscoMessage(b, ipp) {
|
|
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 {
|
|
ep = c.findEndpoint(ipp, b)
|
|
if ep == nil {
|
|
return nil, false
|
|
}
|
|
if de, ok := ep.(*discoEndpoint); ok {
|
|
cache.ipp = ipp
|
|
cache.de = de
|
|
cache.gen = de.numStopAndReset()
|
|
}
|
|
}
|
|
c.noteRecvActivityFromEndpoint(ep)
|
|
return ep, true
|
|
}
|
|
|
|
var errLoopAgain = errors.New("received packet was not a wireguard-go packet or no endpoint found")
|
|
|
|
// receiveIPv4DERP reads a packet from c.derpRecvCh into b and returns the associated endpoint.
|
|
//
|
|
// If the packet was a disco message or the peer endpoint wasn't
|
|
// found, the returned error is errLoopAgain.
|
|
func (c *Conn) receiveIPv4DERP(b []byte) (n int, ep conn.Endpoint, err error) {
|
|
var dm derpReadResult
|
|
select {
|
|
case <-c.donec:
|
|
// Socket has been shut down. All the producers of packets
|
|
// respond to the context cancellation and go away, so we have
|
|
// to also unblock and return an error, to inform wireguard-go
|
|
// that this socket has gone away.
|
|
//
|
|
// Specifically, wireguard-go depends on its bind.Conn having
|
|
// the standard socket behavior, which is that a Close()
|
|
// unblocks any concurrent Read()s. wireguard-go itself calls
|
|
// Clos() on magicsock, and expects ReceiveIPv4 to unblock
|
|
// with an error so it can clean up.
|
|
return 0, nil, errors.New("socket closed")
|
|
case dm = <-c.derpRecvCh:
|
|
// Below.
|
|
}
|
|
if atomic.AddInt64(&c.derpRecvCountAtomic, -1) == 0 {
|
|
c.pconn4.SetReadDeadline(time.Time{})
|
|
}
|
|
if dm.copyBuf == nil {
|
|
testCounterZeroDerpReadResultRecv.Add(1)
|
|
return 0, nil, errLoopAgain
|
|
}
|
|
|
|
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 ReceiveIPv4 buf size %d", n, ncopy)
|
|
c.logf("magicsock: %v", err)
|
|
return 0, nil, err
|
|
}
|
|
|
|
ipp := netaddr.IPPort{IP: derpMagicIPAddr, Port: uint16(regionID)}
|
|
if c.handleDiscoMessage(b[:n], ipp) {
|
|
return 0, nil, errLoopAgain
|
|
}
|
|
|
|
var (
|
|
didNoteRecvActivity bool
|
|
discoEp *discoEndpoint
|
|
asEp *addrSet
|
|
)
|
|
c.mu.Lock()
|
|
if dk, ok := c.discoOfNode[tailcfg.NodeKey(dm.src)]; ok {
|
|
discoEp = c.endpointOfDisco[dk]
|
|
// If we know about the node (it's in discoOfNode) but don't know about the
|
|
// endpoint, that's because it's an idle peer that doesn't yet exist in the
|
|
// wireguard config. So run the receive hook, if defined, which should
|
|
// create the wireguard peer.
|
|
if discoEp == nil && c.noteRecvActivity != nil {
|
|
didNoteRecvActivity = true
|
|
c.mu.Unlock() // release lock before calling noteRecvActivity
|
|
c.noteRecvActivity(dk) // (calls back into CreateEndpoint)
|
|
// Now require the lock. No invariants need to be rechecked; just
|
|
// 1-2 map lookups follow that are harmless if, say, the peer has
|
|
// been deleted during this time.
|
|
c.mu.Lock()
|
|
|
|
discoEp = c.endpointOfDisco[dk]
|
|
c.logf("magicsock: DERP packet received from idle peer %v; created=%v", dm.src.ShortString(), discoEp != nil)
|
|
}
|
|
}
|
|
if !c.disableLegacy {
|
|
asEp = c.addrsByKey[dm.src]
|
|
}
|
|
c.mu.Unlock()
|
|
|
|
if discoEp != nil {
|
|
ep = discoEp
|
|
} else if asEp != nil {
|
|
ep = asEp
|
|
} else {
|
|
key := wgkey.Key(dm.src)
|
|
c.logf("magicsock: DERP packet from unknown key: %s", key.ShortString())
|
|
ep = c.findEndpoint(ipp, b[:n])
|
|
if ep == nil {
|
|
return 0, nil, errLoopAgain
|
|
}
|
|
}
|
|
|
|
if !didNoteRecvActivity {
|
|
c.noteRecvActivityFromEndpoint(ep)
|
|
}
|
|
return n, ep, nil
|
|
}
|
|
|
|
// 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
|
|
)
|
|
|
|
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[:]...)
|
|
sharedKey := c.sharedDiscoKeyLocked(dstDisco)
|
|
c.mu.Unlock()
|
|
|
|
pkt = box.SealAfterPrecomputation(pkt, m.AppendMarshal(nil), &nonce, sharedKey)
|
|
sent, err = c.sendAddr(dst, key.Public(dstKey), pkt)
|
|
if sent {
|
|
if logLevel == discoLog || (logLevel == discoVerboseLog && debugDisco) {
|
|
c.logf("[v1] magicsock: disco: %v->%v (%v, %v) sent %v", c.discoShort, dstDisco.ShortString(), dstKey.ShortString(), 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 addr will be derpMagicIP (with
|
|
// port being the region)
|
|
func (c *Conn) handleDiscoMessage(msg []byte, src netaddr.IPPort) (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
|
|
}
|
|
|
|
peerNode, ok := c.nodeOfDisco[sender]
|
|
if !ok {
|
|
if debugDisco {
|
|
c.logf("magicsock: disco: ignoring disco-looking frame, don't know node for %v", sender.ShortString())
|
|
}
|
|
return
|
|
}
|
|
|
|
needsRecvActivityCall := false
|
|
de, endpointFound0 := c.endpointOfDisco[sender]
|
|
if !endpointFound0 {
|
|
// We don't have an active endpoint for this sender but we knew about the node, so
|
|
// it's an idle endpoint that doesn't yet exist in the wireguard config. We now have
|
|
// to notify the userspace engine (via noteRecvActivity) so wireguard-go can create
|
|
// an Endpoint (ultimately calling our CreateEndpoint).
|
|
c.logf("magicsock: got disco message from idle peer, starting lazy conf for %v, %v", peerNode.Key.ShortString(), sender.ShortString())
|
|
if c.noteRecvActivity == nil {
|
|
c.logf("magicsock: [unexpected] have node without endpoint, without c.noteRecvActivity hook")
|
|
return
|
|
}
|
|
needsRecvActivityCall = true
|
|
} else {
|
|
needsRecvActivityCall = de.isFirstRecvActivityInAwhile()
|
|
}
|
|
if needsRecvActivityCall && c.noteRecvActivity != nil {
|
|
// We can't hold Conn.mu while calling noteRecvActivity.
|
|
// noteRecvActivity acquires userspaceEngine.wgLock (and per our
|
|
// lock ordering rules: wgLock must come first), and also calls
|
|
// back into our Conn.CreateEndpoint, which would double-acquire
|
|
// Conn.mu.
|
|
c.mu.Unlock()
|
|
c.noteRecvActivity(sender)
|
|
c.mu.Lock() // re-acquire
|
|
|
|
// Now, recheck invariants that might've changed while we'd
|
|
// released the lock, which isn't much:
|
|
if c.closed || c.privateKey.IsZero() {
|
|
return
|
|
}
|
|
de, ok = c.endpointOfDisco[sender]
|
|
if !ok {
|
|
if _, ok := c.nodeOfDisco[sender]; !ok {
|
|
// They just disappeared while we'd released the lock.
|
|
return false
|
|
}
|
|
c.logf("magicsock: [unexpected] lazy endpoint not created for %v, %v", peerNode.Key.ShortString(), sender.ShortString())
|
|
return
|
|
}
|
|
if !endpointFound0 {
|
|
c.logf("magicsock: lazy endpoint created via disco message for %v, %v", peerNode.Key.ShortString(), sender.ShortString())
|
|
}
|
|
}
|
|
|
|
// First, do we even know (and thus care) about this sender? If not,
|
|
// don't bother decrypting it.
|
|
|
|
var nonce [disco.NonceLen]byte
|
|
copy(nonce[:], msg[len(disco.Magic)+len(key.Public{}):])
|
|
sealedBox := msg[headerLen:]
|
|
payload, ok := box.OpenAfterPrecomputation(nil, sealedBox, &nonce, c.sharedDiscoKeyLocked(sender))
|
|
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 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, de, src, sender, peerNode)
|
|
case *disco.Pong:
|
|
if de == nil {
|
|
return
|
|
}
|
|
de.handlePongConnLocked(dm, src)
|
|
case *disco.CallMeMaybe:
|
|
if src.IP != derpMagicIPAddr {
|
|
// CallMeMaybe messages should only come via DERP.
|
|
c.logf("[unexpected] CallMeMaybe packets should only come via DERP")
|
|
return
|
|
}
|
|
if de != nil {
|
|
c.logf("magicsock: disco: %v<-%v (%v, %v) got call-me-maybe, %d endpoints",
|
|
c.discoShort, de.discoShort,
|
|
de.publicKey.ShortString(), derpStr(src.String()),
|
|
len(dm.MyNumber))
|
|
go de.handleCallMeMaybe(dm)
|
|
}
|
|
}
|
|
return
|
|
}
|
|
|
|
func (c *Conn) handlePingLocked(dm *disco.Ping, de *discoEndpoint, src netaddr.IPPort, sender tailcfg.DiscoKey, peerNode *tailcfg.Node) {
|
|
if peerNode == nil {
|
|
c.logf("magicsock: disco: [unexpected] ignoring ping from unknown peer Node")
|
|
return
|
|
}
|
|
likelyHeartBeat := src == de.lastPingFrom && time.Since(de.lastPingTime) < 5*time.Second
|
|
de.lastPingFrom = src
|
|
de.lastPingTime = time.Now()
|
|
if !likelyHeartBeat || debugDisco {
|
|
c.logf("[v1] magicsock: disco: %v<-%v (%v, %v) got ping tx=%x", c.discoShort, de.discoShort, peerNode.Key.ShortString(), src, dm.TxID[:6])
|
|
}
|
|
|
|
// Remember this route if not present.
|
|
c.setAddrToDiscoLocked(src, sender, nil)
|
|
de.addCandidateEndpoint(src)
|
|
|
|
ipDst := src
|
|
discoDest := sender
|
|
go c.sendDiscoMessage(ipDst, peerNode.Key, 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 *discoEndpoint) {
|
|
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[*discoEndpoint]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 {
|
|
if ipp, err := netaddr.ParseIPPort(ep); err == nil {
|
|
eps = append(eps, ipp)
|
|
}
|
|
}
|
|
go de.sendDiscoMessage(derpAddr, &disco.CallMeMaybe{MyNumber: eps}, discoLog)
|
|
}
|
|
|
|
// setAddrToDiscoLocked records that newk is at src.
|
|
//
|
|
// c.mu must be held.
|
|
//
|
|
// If the caller already has a discoEndpoint mutex held as well, it
|
|
// can be passed in as alreadyLocked so it won't be re-acquired during
|
|
// any lazy cleanup of the mapping.
|
|
func (c *Conn) setAddrToDiscoLocked(src netaddr.IPPort, newk tailcfg.DiscoKey, alreadyLocked *discoEndpoint) {
|
|
oldk, ok := c.discoOfAddr[src]
|
|
if ok && oldk == newk {
|
|
return
|
|
}
|
|
if ok {
|
|
c.logf("[v1] magicsock: disco: changing mapping of %v from %x=>%x", src, oldk.ShortString(), newk.ShortString())
|
|
} else {
|
|
c.logf("[v1] magicsock: disco: adding mapping of %v to %v", src, newk.ShortString())
|
|
}
|
|
c.discoOfAddr[src] = newk
|
|
if !ok {
|
|
c.cleanDiscoOfAddrLocked(alreadyLocked)
|
|
}
|
|
}
|
|
|
|
// cleanDiscoOfAddrLocked lazily checks a few entries in c.discoOfAddr
|
|
// and deletes them if they're stale. It has no pointers in it so we
|
|
// don't go through the effort of keeping it aggressively
|
|
// pruned. Instead, we lazily clean it whenever it grows.
|
|
//
|
|
// c.mu must be held.
|
|
//
|
|
// If the caller already has a discoEndpoint mutex held as well, it
|
|
// can be passed in as alreadyLocked so it won't be re-acquired.
|
|
func (c *Conn) cleanDiscoOfAddrLocked(alreadyLocked *discoEndpoint) {
|
|
// If it's small enough, don't worry about it.
|
|
if len(c.discoOfAddr) < 16 {
|
|
return
|
|
}
|
|
|
|
const checkEntries = 5 // per one unit of growth
|
|
|
|
// Take advantage of Go's random map iteration to check & clean
|
|
// a few entries.
|
|
n := 0
|
|
for ipp, dk := range c.discoOfAddr {
|
|
n++
|
|
if n > checkEntries {
|
|
return
|
|
}
|
|
de, ok := c.endpointOfDisco[dk]
|
|
if !ok {
|
|
// This discokey isn't even known anymore. Clean.
|
|
delete(c.discoOfAddr, ipp)
|
|
continue
|
|
}
|
|
if de != alreadyLocked {
|
|
de.mu.Lock()
|
|
}
|
|
if _, ok := de.endpointState[ipp]; !ok {
|
|
// The discoEndpoint no longer knows about that endpoint.
|
|
// It must've changed. Clean.
|
|
delete(c.discoOfAddr, ipp)
|
|
}
|
|
if de != alreadyLocked {
|
|
de.mu.Unlock()
|
|
}
|
|
}
|
|
}
|
|
|
|
func (c *Conn) sharedDiscoKeyLocked(k tailcfg.DiscoKey) *[32]byte {
|
|
if v, ok := c.sharedDiscoKey[k]; ok {
|
|
return v
|
|
}
|
|
shared := new([32]byte)
|
|
box.Precompute(shared, key.Public(k).B32(), c.discoPrivate.B32())
|
|
c.sharedDiscoKey[k] = shared
|
|
return shared
|
|
}
|
|
|
|
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")
|
|
}
|
|
}
|
|
|
|
// 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 wgkey.Private) error {
|
|
c.mu.Lock()
|
|
defer c.mu.Unlock()
|
|
|
|
oldKey, newKey := c.privateKey, key.Private(privateKey)
|
|
if newKey == oldKey {
|
|
return nil
|
|
}
|
|
c.privateKey = newKey
|
|
c.havePrivateKey.Set(!newKey.IsZero())
|
|
|
|
if oldKey.IsZero() {
|
|
c.everHadKey = true
|
|
c.logf("magicsock: SetPrivateKey called (init)")
|
|
if c.started {
|
|
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() {
|
|
for _, de := range c.endpointOfDisco {
|
|
de.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.Public]struct{}) {
|
|
c.mu.Lock()
|
|
defer c.mu.Unlock()
|
|
|
|
oldPeers := c.peerSet
|
|
c.peerSet = newPeers
|
|
|
|
// Clean up any key.Public-keyed maps for peers that no longer
|
|
// exist.
|
|
for peer := range oldPeers {
|
|
if _, ok := newPeers[peer]; !ok {
|
|
delete(c.addrsByKey, peer)
|
|
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
|
|
}
|
|
|
|
if c.started {
|
|
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.netMap != nil && nodesEqual(c.netMap.Peers, nm.Peers) {
|
|
return
|
|
}
|
|
|
|
numDisco := 0
|
|
for _, n := range nm.Peers {
|
|
if n.DiscoKey.IsZero() {
|
|
continue
|
|
}
|
|
numDisco++
|
|
if ep, ok := c.endpointOfDisco[n.DiscoKey]; ok && ep.publicKey == n.Key {
|
|
ep.updateFromNode(n)
|
|
} else if ok {
|
|
c.logf("magicsock: disco key %v changed from node key %v to %v", n.DiscoKey, ep.publicKey.ShortString(), n.Key.ShortString())
|
|
ep.stopAndReset()
|
|
delete(c.endpointOfDisco, n.DiscoKey)
|
|
}
|
|
}
|
|
|
|
c.logf("[v1] magicsock: got updated network map; %d peers (%d with discokey)", len(nm.Peers), numDisco)
|
|
c.netMap = nm
|
|
|
|
// Build and/or update node<->disco maps, only reallocating if
|
|
// the set of discokeys changed.
|
|
for pass := 1; pass <= 2; pass++ {
|
|
if c.nodeOfDisco == nil || pass == 2 {
|
|
c.nodeOfDisco = map[tailcfg.DiscoKey]*tailcfg.Node{}
|
|
c.discoOfNode = map[tailcfg.NodeKey]tailcfg.DiscoKey{}
|
|
}
|
|
for _, n := range nm.Peers {
|
|
if !n.DiscoKey.IsZero() {
|
|
c.nodeOfDisco[n.DiscoKey] = n
|
|
if old, ok := c.discoOfNode[n.Key]; ok && old != n.DiscoKey {
|
|
c.logf("magicsock: node %s changed discovery key from %x to %x", n.Key.ShortString(), old[:8], n.DiscoKey[:8])
|
|
}
|
|
c.discoOfNode[n.Key] = n.DiscoKey
|
|
}
|
|
}
|
|
if len(c.nodeOfDisco) == numDisco && len(c.discoOfNode) == numDisco {
|
|
break
|
|
}
|
|
}
|
|
|
|
// Clean c.endpointOfDisco for discovery keys that are no longer present.
|
|
for dk, de := range c.endpointOfDisco {
|
|
if _, ok := c.nodeOfDisco[dk]; !ok {
|
|
de.stopAndReset()
|
|
delete(c.endpointOfDisco, dk)
|
|
delete(c.sharedDiscoKey, 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 []string, reasons map[string]string) {
|
|
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, reasons[ep])
|
|
}
|
|
}))
|
|
}
|
|
|
|
// 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)
|
|
}
|
|
|
|
func (c *Conn) SetMark(value uint32) error { return nil }
|
|
func (c *Conn) LastMark() uint32 { return 0 }
|
|
|
|
// 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()
|
|
|
|
for _, ep := range c.endpointOfDisco {
|
|
ep.stopAndReset()
|
|
}
|
|
|
|
c.closed = true
|
|
c.connCtxCancel()
|
|
c.closeAllDerpLocked("conn-close")
|
|
if c.pconn6 != nil {
|
|
c.pconn6.Close()
|
|
}
|
|
err := 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 err
|
|
}
|
|
|
|
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
|
|
}
|
|
|
|
// 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.started {
|
|
panic("call to ReSTUN before Start")
|
|
}
|
|
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 err := c.bind1(&c.pconn4, "udp4"); err != nil {
|
|
return err
|
|
}
|
|
c.portMapper.SetLocalPort(c.LocalPort())
|
|
if err := c.bind1(&c.pconn6, "udp6"); err != nil {
|
|
c.logf("magicsock: ignoring IPv6 bind failure: %v", err)
|
|
}
|
|
return nil
|
|
}
|
|
|
|
func (c *Conn) listenPacket(ctx context.Context, network, addr string) (net.PacketConn, error) {
|
|
if c.packetListener != nil {
|
|
return c.packetListener.ListenPacket(ctx, network, addr)
|
|
}
|
|
return netns.Listener().ListenPacket(ctx, network, addr)
|
|
}
|
|
|
|
func (c *Conn) bind1(ruc **RebindingUDPConn, which string) error {
|
|
host := ""
|
|
if inTest() && !c.simulatedNetwork {
|
|
host = "127.0.0.1"
|
|
if which == "udp6" {
|
|
host = "::1"
|
|
}
|
|
}
|
|
var pc net.PacketConn
|
|
var err error
|
|
listenCtx := context.Background() // unused without DNS name to resolve
|
|
if c.port == 0 && DefaultPort != 0 {
|
|
pc, err = c.listenPacket(listenCtx, which, net.JoinHostPort(host, fmt.Sprint(DefaultPort)))
|
|
if err != nil {
|
|
c.logf("magicsock: bind: default port %s/%v unavailable; picking random", which, DefaultPort)
|
|
}
|
|
}
|
|
if pc == nil {
|
|
pc, err = c.listenPacket(listenCtx, which, net.JoinHostPort(host, fmt.Sprint(c.port)))
|
|
}
|
|
if err != nil {
|
|
c.logf("magicsock: bind(%s/%v): %v", which, c.port, err)
|
|
return fmt.Errorf("magicsock: bind: %s/%d: %v", which, c.port, err)
|
|
}
|
|
if *ruc == nil {
|
|
*ruc = new(RebindingUDPConn)
|
|
}
|
|
(*ruc).Reset(pc)
|
|
return nil
|
|
}
|
|
|
|
// Rebind closes and re-binds the UDP sockets.
|
|
// It should be followed by a call to ReSTUN.
|
|
func (c *Conn) Rebind() {
|
|
host := ""
|
|
if inTest() && !c.simulatedNetwork {
|
|
host = "127.0.0.1"
|
|
}
|
|
listenCtx := context.Background() // unused without DNS name to resolve
|
|
if c.port != 0 {
|
|
c.pconn4.mu.Lock()
|
|
if err := c.pconn4.pconn.Close(); err != nil {
|
|
c.logf("magicsock: link change close failed: %v", err)
|
|
}
|
|
packetConn, err := c.listenPacket(listenCtx, "udp4", fmt.Sprintf("%s:%d", host, c.port))
|
|
if err == nil {
|
|
c.logf("magicsock: link change rebound port: %d", c.port)
|
|
c.pconn4.pconn = packetConn.(*net.UDPConn)
|
|
c.pconn4.mu.Unlock()
|
|
return
|
|
}
|
|
c.logf("magicsock: link change unable to bind fixed port %d: %v, falling back to random port", c.port, err)
|
|
c.pconn4.mu.Unlock()
|
|
}
|
|
c.logf("magicsock: link change, binding new port")
|
|
packetConn, err := c.listenPacket(listenCtx, "udp4", host+":0")
|
|
if err != nil {
|
|
c.logf("magicsock: link change failed to bind new port: %v", err)
|
|
return
|
|
}
|
|
c.pconn4.Reset(packetConn.(*net.UDPConn))
|
|
c.portMapper.SetLocalPort(c.LocalPort())
|
|
|
|
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 and
|
|
// re-enables spraying.
|
|
// 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()
|
|
for _, de := range c.endpointOfDisco {
|
|
de.noteConnectivityChange()
|
|
}
|
|
c.resetAddrSetStatesLocked()
|
|
}
|
|
|
|
// 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
|
|
}
|
|
|
|
// CreateBind is called by WireGuard to create a UDP binding.
|
|
func (c *Conn) CreateBind(uint16) (conn.Bind, uint16, error) {
|
|
return c, c.LocalPort(), nil
|
|
}
|
|
|
|
// CreateEndpoint is called by WireGuard to connect to an endpoint.
|
|
//
|
|
// The key is the public key of the peer and addrs is either:
|
|
//
|
|
// 1) a comma-separated list of UDP ip:ports (the peer doesn't have a discovery key)
|
|
// 2) "<hex-discovery-key>.disco.tailscale:12345", a magic value that means the peer
|
|
// is running code that supports active discovery, so CreateEndpoint returns
|
|
// a discoEndpoint.
|
|
//
|
|
|
|
func (c *Conn) CreateEndpoint(pubKey [32]byte, addrs string) (conn.Endpoint, error) {
|
|
c.mu.Lock()
|
|
defer c.mu.Unlock()
|
|
|
|
pk := key.Public(pubKey)
|
|
c.logf("magicsock: CreateEndpoint: key=%s: %s", pk.ShortString(), derpStr(addrs))
|
|
|
|
if !strings.HasSuffix(addrs, wgcfg.EndpointDiscoSuffix) {
|
|
return c.createLegacyEndpointLocked(pk, addrs)
|
|
}
|
|
|
|
discoHex := strings.TrimSuffix(addrs, wgcfg.EndpointDiscoSuffix)
|
|
discoKey, err := key.NewPublicFromHexMem(mem.S(discoHex))
|
|
if err != nil {
|
|
return nil, fmt.Errorf("magicsock: invalid discokey endpoint %q for %v: %w", addrs, pk.ShortString(), err)
|
|
}
|
|
de := &discoEndpoint{
|
|
c: c,
|
|
publicKey: tailcfg.NodeKey(pk), // peer public key (for WireGuard + DERP)
|
|
discoKey: tailcfg.DiscoKey(discoKey), // for discovery mesages
|
|
discoShort: tailcfg.DiscoKey(discoKey).ShortString(),
|
|
wgEndpointHostPort: addrs,
|
|
sentPing: map[stun.TxID]sentPing{},
|
|
endpointState: map[netaddr.IPPort]*endpointState{},
|
|
}
|
|
de.initFakeUDPAddr()
|
|
de.updateFromNode(c.nodeOfDisco[de.discoKey])
|
|
c.endpointOfDisco[de.discoKey] = de
|
|
return de, 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
|
|
}
|
|
|
|
func (c *RebindingUDPConn) Reset(pconn net.PacketConn) {
|
|
c.mu.Lock()
|
|
old := c.pconn
|
|
c.pconn = pconn
|
|
c.mu.Unlock()
|
|
|
|
if old != nil {
|
|
old.Close()
|
|
}
|
|
}
|
|
|
|
// ReadFromNetaddr 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 {
|
|
c.mu.Lock()
|
|
pconn := c.pconn
|
|
c.mu.Unlock()
|
|
|
|
n, addr, err := pconn.ReadFrom(b)
|
|
if err != nil {
|
|
c.mu.Lock()
|
|
pconn2 := c.pconn
|
|
c.mu.Unlock()
|
|
|
|
if pconn != pconn2 {
|
|
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 {
|
|
c.mu.Lock()
|
|
pconn := c.pconn
|
|
c.mu.Unlock()
|
|
|
|
// 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 {
|
|
c.mu.Lock()
|
|
pconn2 := c.pconn
|
|
c.mu.Unlock()
|
|
|
|
if pconn != pconn2 {
|
|
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.pconn.LocalAddr().(*net.UDPAddr)
|
|
}
|
|
|
|
func (c *RebindingUDPConn) Close() error {
|
|
c.mu.Lock()
|
|
defer c.mu.Unlock()
|
|
return c.pconn.Close()
|
|
}
|
|
|
|
func (c *RebindingUDPConn) SetReadDeadline(t time.Time) {
|
|
c.mu.Lock()
|
|
defer c.mu.Unlock()
|
|
c.pconn.SetReadDeadline(t)
|
|
}
|
|
|
|
func (c *RebindingUDPConn) WriteToUDP(b []byte, addr *net.UDPAddr) (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 (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
|
|
}
|
|
}
|
|
|
|
// 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 peerShort(k key.Public) string {
|
|
k2 := wgkey.Key(k)
|
|
return k2.ShortString()
|
|
}
|
|
|
|
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()
|
|
|
|
ss := &ipnstate.PeerStatus{
|
|
PublicKey: c.privateKey.Public(),
|
|
Addrs: c.lastEndpoints,
|
|
OS: version.OS(),
|
|
}
|
|
if c.netMap != nil {
|
|
ss.HostName = c.netMap.Hostinfo.Hostname
|
|
ss.DNSName = c.netMap.Name
|
|
ss.UserID = c.netMap.User
|
|
} else {
|
|
ss.HostName, _ = os.Hostname()
|
|
}
|
|
if c.derpMap != nil {
|
|
derpRegion, ok := c.derpMap.Regions[c.myDerp]
|
|
if ok {
|
|
ss.Relay = derpRegion.RegionCode
|
|
}
|
|
}
|
|
|
|
if c.netMap != nil {
|
|
for _, addr := range c.netMap.Addresses {
|
|
if !addr.IsSingleIP() {
|
|
continue
|
|
}
|
|
sb.AddTailscaleIP(addr.IP)
|
|
// TailAddr only allows for a single Tailscale IP. For
|
|
// readability of `tailscale status`, make it the IPv4
|
|
// address.
|
|
if addr.IP.Is4() {
|
|
ss.TailAddr = addr.IP.String()
|
|
}
|
|
}
|
|
}
|
|
sb.SetSelfStatus(ss)
|
|
|
|
for dk, n := range c.nodeOfDisco {
|
|
ps := &ipnstate.PeerStatus{InMagicSock: true}
|
|
ps.Addrs = append(ps.Addrs, n.Endpoints...)
|
|
ps.Relay = c.derpRegionCodeOfAddrLocked(n.DERP)
|
|
if de, ok := c.endpointOfDisco[dk]; ok {
|
|
de.populatePeerStatus(ps)
|
|
}
|
|
sb.AddPeer(key.Public(n.Key), ps)
|
|
}
|
|
// Old-style (pre-disco) peers:
|
|
for k, as := range c.addrsByKey {
|
|
ps := &ipnstate.PeerStatus{
|
|
InMagicSock: true,
|
|
Relay: c.derpRegionCodeOfIDLocked(as.derpID()),
|
|
}
|
|
as.populatePeerStatus(ps)
|
|
sb.AddPeer(k, 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 for new-style peers that
|
|
// advertise a DiscoKey and participate in active discovery.
|
|
type discoEndpoint struct {
|
|
// atomically accessed; declared first for alignment reasons
|
|
lastRecvUnixAtomic int64
|
|
numStopAndResetAtomic int64
|
|
|
|
// These fields are initialized once and never modified.
|
|
c *Conn
|
|
publicKey tailcfg.NodeKey // peer public key (for WireGuard + DERP)
|
|
discoKey tailcfg.DiscoKey // for discovery mesages
|
|
discoShort string // ShortString of discoKey
|
|
fakeWGAddr netaddr.IPPort // the UDP address we tell wireguard-go we're using
|
|
wgEndpointHostPort string // string from CreateEndpoint: "<hex-discovery-key>.disco.tailscale:12345"
|
|
|
|
// Owned by Conn.mu:
|
|
lastPingFrom netaddr.IPPort
|
|
lastPingTime time.Time
|
|
|
|
// mu protects all following fields.
|
|
mu sync.Mutex // Lock ordering: Conn.mu, then discoEndpoint.mu
|
|
|
|
heartBeatTimer *time.Timer // nil when idle
|
|
lastSend time.Time // last time there was outgoing packets sent to this peer (from wireguard-go)
|
|
lastFullPing time.Time // last time we pinged all endpoints
|
|
derpAddr netaddr.IPPort // fallback/bootstrap path, if non-zero (non-zero for well-behaved clients)
|
|
|
|
bestAddr netaddr.IPPort // best non-DERP path; zero if none
|
|
bestAddrLatency time.Duration
|
|
bestAddrAt time.Time // time best address re-confirmed
|
|
trustBestAddrUntil time.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 discoEndpoint 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
|
|
|
|
// 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
|
|
|
|
// pingTimeoutDuration is how long we wait for a pong reply before
|
|
// assuming it's never coming.
|
|
pingTimeoutDuration = 5 * 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
|
|
)
|
|
|
|
// endpointState is some state and history for a specific endpoint of
|
|
// a discoEndpoint. (The subject is the discoEndpoint.endpointState
|
|
// map key)
|
|
type endpointState struct {
|
|
// all fields guarded by discoEndpoint.mu
|
|
|
|
// lastPing is the last (outgoing) ping time.
|
|
lastPing time.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 discoEndpoint'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 *discoEndpoint) deleteEndpointLocked(ep netaddr.IPPort) {
|
|
delete(de.endpointState, ep)
|
|
if de.bestAddr == ep {
|
|
de.bestAddr = netaddr.IPPort{}
|
|
}
|
|
}
|
|
|
|
// pongHistoryCount is how many pongReply values we keep per endpointState
|
|
const pongHistoryCount = 64
|
|
|
|
type pongReply struct {
|
|
latency time.Duration
|
|
pongAt time.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 time.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 *discoEndpoint) initFakeUDPAddr() {
|
|
var addr [16]byte
|
|
addr[0] = 0xfd
|
|
addr[1] = 0x00
|
|
binary.BigEndian.PutUint64(addr[2:], uint64(reflect.ValueOf(de).Pointer()))
|
|
de.fakeWGAddr = netaddr.IPPort{
|
|
IP: netaddr.IPFrom16(addr),
|
|
Port: 12345,
|
|
}
|
|
}
|
|
|
|
// isFirstRecvActivityInAwhile notes that receive activity has occured for this
|
|
// endpoint and reports whether it's been at least 10 seconds since the last
|
|
// receive activity (including having never received from this peer before).
|
|
func (de *discoEndpoint) isFirstRecvActivityInAwhile() bool {
|
|
now := time.Now().Unix()
|
|
old := atomic.LoadInt64(&de.lastRecvUnixAtomic)
|
|
if old <= now-10 {
|
|
atomic.StoreInt64(&de.lastRecvUnixAtomic, now)
|
|
return true
|
|
}
|
|
return false
|
|
}
|
|
|
|
// 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 *discoEndpoint) String() string {
|
|
return fmt.Sprintf("magicsock.discoEndpoint{%v, %v}", de.publicKey.ShortString(), de.discoShort)
|
|
}
|
|
|
|
func (de *discoEndpoint) ClearSrc() {}
|
|
func (de *discoEndpoint) SrcToString() string { panic("unused") } // unused by wireguard-go
|
|
func (de *discoEndpoint) SrcIP() net.IP { panic("unused") } // unused by wireguard-go
|
|
func (de *discoEndpoint) DstToString() string { return de.wgEndpointHostPort }
|
|
func (de *discoEndpoint) DstIP() net.IP { panic("unused") }
|
|
func (de *discoEndpoint) DstToBytes() []byte { return packIPPort(de.fakeWGAddr) }
|
|
|
|
// 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 *discoEndpoint) addrForSendLocked(now time.Time) (udpAddr, derpAddr netaddr.IPPort) {
|
|
udpAddr = de.bestAddr
|
|
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 *discoEndpoint) heartbeat() {
|
|
de.mu.Lock()
|
|
defer de.mu.Unlock()
|
|
|
|
de.heartBeatTimer = nil
|
|
|
|
if de.lastSend.IsZero() {
|
|
// Shouldn't happen.
|
|
return
|
|
}
|
|
|
|
if time.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 := time.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 *discoEndpoint) wantFullPingLocked(now time.Time) bool {
|
|
if de.bestAddr.IsZero() || de.lastFullPing.IsZero() {
|
|
return true
|
|
}
|
|
if now.After(de.trustBestAddrUntil) {
|
|
return true
|
|
}
|
|
if de.bestAddrLatency <= goodEnoughLatency {
|
|
return false
|
|
}
|
|
if now.Sub(de.lastFullPing) >= upgradeInterval {
|
|
return true
|
|
}
|
|
return false
|
|
}
|
|
|
|
func (de *discoEndpoint) noteActiveLocked() {
|
|
de.lastSend = time.Now()
|
|
if de.heartBeatTimer == nil {
|
|
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 *discoEndpoint) cliPing(res *ipnstate.PingResult, cb func(*ipnstate.PingResult)) {
|
|
de.mu.Lock()
|
|
defer de.mu.Unlock()
|
|
|
|
de.pendingCLIPings = append(de.pendingCLIPings, pendingCLIPing{res, cb})
|
|
|
|
now := time.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 {
|
|
for ep := range de.endpointState {
|
|
de.startPingLocked(ep, now, pingCLI)
|
|
}
|
|
}
|
|
de.noteActiveLocked()
|
|
}
|
|
|
|
func (de *discoEndpoint) send(b []byte) error {
|
|
now := time.Now()
|
|
|
|
de.mu.Lock()
|
|
udpAddr, derpAddr := de.addrForSendLocked(now)
|
|
if 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.Public(de.publicKey), b)
|
|
}
|
|
if !derpAddr.IsZero() {
|
|
if ok, _ := de.c.sendAddr(derpAddr, key.Public(de.publicKey), b); ok && err != nil {
|
|
// UDP failed but DERP worked, so good enough:
|
|
return nil
|
|
}
|
|
}
|
|
return err
|
|
}
|
|
|
|
func (de *discoEndpoint) pingTimeout(txid stun.TxID) {
|
|
de.mu.Lock()
|
|
defer de.mu.Unlock()
|
|
sp, ok := de.sentPing[txid]
|
|
if !ok {
|
|
return
|
|
}
|
|
if debugDisco || de.bestAddr.IsZero() || time.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 *discoEndpoint) forgetPing(txid stun.TxID) {
|
|
de.mu.Lock()
|
|
defer de.mu.Unlock()
|
|
if sp, ok := de.sentPing[txid]; ok {
|
|
de.removeSentPingLocked(txid, sp)
|
|
}
|
|
}
|
|
|
|
func (de *discoEndpoint) 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 *discoEndpoint) sendDiscoPing(ep netaddr.IPPort, txid stun.TxID, logLevel discoLogLevel) {
|
|
sent, _ := de.sendDiscoMessage(ep, &disco.Ping{TxID: [12]byte(txid)}, logLevel)
|
|
if !sent {
|
|
de.forgetPing(txid)
|
|
}
|
|
}
|
|
|
|
// discoPingPurpose is the reason why a discovery ping message was sent.
|
|
type discoPingPurpose int
|
|
|
|
//go:generate 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 *discoEndpoint) startPingLocked(ep netaddr.IPPort, now time.Time, purpose discoPingPurpose) {
|
|
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 *discoEndpoint) sendPingsLocked(now time.Time, sendCallMeMaybe bool) {
|
|
de.lastFullPing = now
|
|
var sentAny bool
|
|
for ep, st := range de.endpointState {
|
|
if st.shouldDeleteLocked() {
|
|
de.deleteEndpointLocked(ep)
|
|
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 *discoEndpoint) 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 *discoEndpoint) updateFromNode(n *tailcfg.Node) {
|
|
if n == nil {
|
|
// TODO: log, error, count? if this even happens.
|
|
return
|
|
}
|
|
de.mu.Lock()
|
|
defer de.mu.Unlock()
|
|
|
|
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 *discoEndpoint) 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("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("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 *discoEndpoint) noteConnectivityChange() {
|
|
de.mu.Lock()
|
|
defer de.mu.Unlock()
|
|
|
|
de.trustBestAddrUntil = time.Time{}
|
|
}
|
|
|
|
// handlePongConnLocked handles a Pong message (a reply to an earlier ping).
|
|
// It should be called with the Conn.mu held.
|
|
func (de *discoEndpoint) handlePongConnLocked(m *disco.Pong, src netaddr.IPPort) {
|
|
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. Ignore.
|
|
return
|
|
}
|
|
de.removeSentPingLocked(m.TxID, sp)
|
|
|
|
now := time.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.setAddrToDiscoLocked(src, de.discoKey, de)
|
|
|
|
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 {
|
|
if de.bestAddr.IsZero() || latency < de.bestAddrLatency {
|
|
if de.bestAddr != sp.to {
|
|
de.c.logf("magicsock: disco: node %v %v now using %v", de.publicKey.ShortString(), de.discoShort, sp.to)
|
|
de.bestAddr = sp.to
|
|
}
|
|
}
|
|
if de.bestAddr == sp.to {
|
|
de.bestAddrLatency = latency
|
|
de.bestAddrAt = now
|
|
de.trustBestAddrUntil = now.Add(trustUDPAddrDuration)
|
|
}
|
|
}
|
|
}
|
|
|
|
// discoEndpoint.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 *discoEndpoint) handleCallMeMaybe(m *disco.CallMeMaybe) {
|
|
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("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 = time.Time{}
|
|
}
|
|
de.sendPingsLocked(time.Now(), false)
|
|
}
|
|
|
|
func (de *discoEndpoint) populatePeerStatus(ps *ipnstate.PeerStatus) {
|
|
de.mu.Lock()
|
|
defer de.mu.Unlock()
|
|
|
|
if de.lastSend.IsZero() {
|
|
return
|
|
}
|
|
|
|
ps.LastWrite = de.lastSend
|
|
|
|
now := time.Now()
|
|
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 transition from running to stopped state (via SetPrivateKey(zero))
|
|
func (de *discoEndpoint) 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[:])
|
|
|
|
// Zero these fields so if the user re-starts the network, the discovery
|
|
// state isn't a mix of before & after two sessions.
|
|
de.lastSend = time.Time{}
|
|
de.lastFullPing = time.Time{}
|
|
de.bestAddr = netaddr.IPPort{}
|
|
de.bestAddrLatency = 0
|
|
de.bestAddrAt = time.Time{}
|
|
de.trustBestAddrUntil = time.Time{}
|
|
for _, es := range de.endpointState {
|
|
es.lastPing = time.Time{}
|
|
}
|
|
|
|
for txid, sp := range de.sentPing {
|
|
de.removeSentPingLocked(txid, sp)
|
|
}
|
|
if de.heartBeatTimer != nil {
|
|
de.heartBeatTimer.Stop()
|
|
de.heartBeatTimer = nil
|
|
}
|
|
de.pendingCLIPings = nil
|
|
}
|
|
|
|
func (de *discoEndpoint) 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-") }
|
|
|
|
// WhoIs reports the node and user who owns the node with the given IP.
|
|
// If ok == true, n and u are valid.
|
|
func (c *Conn) WhoIs(ip netaddr.IP) (n *tailcfg.Node, u tailcfg.UserProfile, ok bool) {
|
|
c.mu.Lock()
|
|
defer c.mu.Unlock()
|
|
if c.netMap == nil {
|
|
return n, u, false
|
|
}
|
|
for _, p := range c.netMap.Peers {
|
|
for _, ipp := range p.Addresses {
|
|
if ipp.IsSingleIP() && ipp.IP == ip {
|
|
u, ok := c.netMap.UserProfiles[p.User]
|
|
return p, u, ok
|
|
}
|
|
}
|
|
}
|
|
return nil, u, false
|
|
}
|
|
|
|
// 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 *discoEndpoint
|
|
}
|