TUN-2714: New edge discovery. Connections try to reconnect to the same edge IP.

This commit is contained in:
Adam Chalmers 2020-02-05 18:55:26 -06:00
parent d6c2c4ee4a
commit a60c0273f5
18 changed files with 1221 additions and 801 deletions

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@ -14,7 +14,7 @@ import (
"github.com/cloudflare/cloudflared/cmd/cloudflared/buildinfo"
"github.com/cloudflare/cloudflared/cmd/cloudflared/config"
"github.com/cloudflare/cloudflared/connection"
"github.com/cloudflare/cloudflared/edgediscovery"
"github.com/cloudflare/cloudflared/origin"
"github.com/cloudflare/cloudflared/tlsconfig"
tunnelpogs "github.com/cloudflare/cloudflared/tunnelrpc/pogs"
@ -280,13 +280,13 @@ func prepareTunnelConfig(
}, nil
}
func serviceDiscoverer(c *cli.Context, logger *logrus.Logger) (connection.EdgeServiceDiscoverer, error) {
func serviceDiscoverer(c *cli.Context, logger *logrus.Logger) (*edgediscovery.Edge, error) {
// If --edge is specfied, resolve edge server addresses
if len(c.StringSlice("edge")) > 0 {
return connection.NewEdgeHostnameResolver(c.StringSlice("edge"))
return edgediscovery.StaticEdge(logger, c.StringSlice("edge"))
}
// Otherwise lookup edge server addresses through service discovery
return connection.NewEdgeAddrResolver(logger)
return edgediscovery.ResolveEdge(logger)
}
func isRunningFromTerminal() bool {

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@ -21,6 +21,8 @@ type Connection struct {
id uuid.UUID
muxer *h2mux.Muxer
addr *net.TCPAddr
isLongLived bool
longLivedID int
}
func newConnection(muxer *h2mux.Muxer, addr *net.TCPAddr) (*Connection, error) {

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@ -1,420 +0,0 @@
package connection
import (
"context"
"crypto/tls"
"fmt"
"math/rand"
"net"
"sync"
"time"
"github.com/pkg/errors"
"github.com/sirupsen/logrus"
)
const (
// Used to discover HA origintunneld servers
srvService = "origintunneld"
srvProto = "tcp"
srvName = "argotunnel.com"
// Used to fallback to DoT when we can't use the default resolver to
// discover HA origintunneld servers (GitHub issue #75).
dotServerName = "cloudflare-dns.com"
dotServerAddr = "1.1.1.1:853"
dotTimeout = time.Duration(15 * time.Second)
// SRV record resolution TTL
resolveEdgeAddrTTL = 1 * time.Hour
subsystemEdgeAddrResolver = "edgeAddrResolver"
)
// Redeclare network functions so they can be overridden in tests.
var (
netLookupSRV = net.LookupSRV
netLookupIP = net.LookupIP
)
// If the call to net.LookupSRV fails, try to fall back to DoT from Cloudflare directly.
//
// Note: Instead of DoT, we could also have used DoH. Either of these:
// - directly via the JSON API (https://1.1.1.1/dns-query?ct=application/dns-json&name=_origintunneld._tcp.argotunnel.com&type=srv)
// - indirectly via `tunneldns.NewUpstreamHTTPS()`
// But both of these cases miss out on a key feature from the stdlib:
// "The returned records are sorted by priority and randomized by weight within a priority."
// (https://golang.org/pkg/net/#Resolver.LookupSRV)
// Does this matter? I don't know. It may someday. Let's use DoT so we don't need to worry about it.
// See also: Go feature request for stdlib-supported DoH: https://github.com/golang/go/issues/27552
var fallbackLookupSRV = lookupSRVWithDOT
var friendlyDNSErrorLines = []string{
`Please try the following things to diagnose this issue:`,
` 1. ensure that argotunnel.com is returning "origintunneld" service records.`,
` Run your system's equivalent of: dig srv _origintunneld._tcp.argotunnel.com`,
` 2. ensure that your DNS resolver is not returning compressed SRV records.`,
` See GitHub issue https://github.com/golang/go/issues/27546`,
` For example, you could use Cloudflare's 1.1.1.1 as your resolver:`,
` https://developers.cloudflare.com/1.1.1.1/setting-up-1.1.1.1/`,
}
// EdgeServiceDiscoverer is an interface for looking up Cloudflare's edge network addresses
type EdgeServiceDiscoverer interface {
// Addr returns an unused address to connect to cloudflare's edge network.
// Before this method returns, the address will be removed from the pool of available addresses,
// so the caller can assume they have exclusive access to the address for tunneling purposes.
// The caller should remember to put it back via ReplaceAddr or MarkAddrBad.
Addr() (*net.TCPAddr, error)
// AnyAddr returns an address to connect to cloudflare's edge network.
// It may or may not be in active use for a tunnel.
// The caller should NOT return it via ReplaceAddr or MarkAddrBad!
AnyAddr() (*net.TCPAddr, error)
// ReplaceAddr is called when the address is no longer needed, e.g. due to a scaling-down of numHAConnections.
// It returns the address to the pool of available addresses.
ReplaceAddr(addr *net.TCPAddr)
// MarkAddrBad is called when there was a connectivity error for the address.
// It marks the address as unused but doesn't return it to the pool of available addresses.
MarkAddrBad(addr *net.TCPAddr)
// AvailableAddrs returns the number of addresses available for use
// (less those that have been marked bad).
AvailableAddrs() int
// Refresh rediscovers Cloudflare's edge network addresses.
// It resets the state of "bad" addresses but not those in active use.
Refresh() error
}
// EdgeAddrResolver discovers the addresses of Cloudflare's edge network through SRV record.
// It implements EdgeServiceDiscoverer interface
type EdgeAddrResolver struct {
sync.Mutex
// HA regions
regions []*region
// Logger for noteworthy events
logger *logrus.Entry
}
type region struct {
// Addresses that we expect will be in active use
addrs []*net.TCPAddr
// Addresses that are in active use.
// This is actually a set of net.TCPAddr's, but we can't make a map like
// map[net.TCPAddr]bool
// since net.TCPAddr contains a field of type net.IP and therefore it cannot be used as a map key.
// So instead we use map[string]*net.TCPAddr, where the keys are obtained by net.TCPAddr.String().
// (We keep the "raw" *net.TCPAddr values for the convenience of AnyAddr(). If that method didn't
// exist, we wouldn't strictly need the values, and this could be a map[string]bool.)
inUse map[string]*net.TCPAddr
// Addresses that were discarded due to a network error.
// Not sure what we'll do with these, but it feels good to keep them around for now.
bad []*net.TCPAddr
}
func NewEdgeAddrResolver(logger *logrus.Logger) (EdgeServiceDiscoverer, error) {
r := &EdgeAddrResolver{
logger: logger.WithField("subsystem", subsystemEdgeAddrResolver),
}
if err := r.Refresh(); err != nil {
return nil, err
}
return r, nil
}
func (r *EdgeAddrResolver) Addr() (*net.TCPAddr, error) {
r.Lock()
defer r.Unlock()
// compute the largest region based on len(addrs)
var largestRegion *region
{
if len(r.regions) == 0 {
return nil, errors.New("No HA regions")
}
largestRegion = r.regions[0]
for _, region := range r.regions[1:] {
if len(region.addrs) > len(largestRegion.addrs) {
largestRegion = region
}
}
if len(largestRegion.addrs) == 0 {
return nil, errors.New("No IP address to claim")
}
}
var addr *net.TCPAddr
addr, largestRegion.addrs = popAddr(largestRegion.addrs)
largestRegion.inUse[addr.String()] = addr
return addr, nil
}
func (r *EdgeAddrResolver) AnyAddr() (*net.TCPAddr, error) {
r.Lock()
defer r.Unlock()
for _, region := range r.regions {
// return an unused addr
if len(region.addrs) > 0 {
return region.addrs[rand.Intn(len(region.addrs))], nil
}
// return an addr that's in use
for _, addr := range region.inUse {
return addr, nil
}
}
return nil, fmt.Errorf("No IP addresses")
}
func (r *EdgeAddrResolver) ReplaceAddr(addr *net.TCPAddr) {
r.Lock()
defer r.Unlock()
addrString := addr.String()
for _, region := range r.regions {
if _, ok := region.inUse[addrString]; ok {
delete(region.inUse, addrString)
region.addrs = append(region.addrs, addr)
break
}
}
}
func (r *EdgeAddrResolver) MarkAddrBad(addr *net.TCPAddr) {
r.Lock()
defer r.Unlock()
addrString := addr.String()
for _, region := range r.regions {
if _, ok := region.inUse[addrString]; ok {
delete(region.inUse, addrString)
region.bad = append(region.bad, addr)
break
}
}
}
func (r *EdgeAddrResolver) AvailableAddrs() int {
r.Lock()
defer r.Unlock()
result := 0
for _, region := range r.regions {
result += len(region.addrs)
}
return result
}
func (r *EdgeAddrResolver) Refresh() error {
addrLists, err := EdgeDiscovery(r.logger)
if err != nil {
return err
}
r.Lock()
defer r.Unlock()
inUse := allInUse(r.regions)
r.regions = makeHARegions(addrLists, inUse)
return nil
}
// EdgeDiscovery implements HA service discovery lookup.
func EdgeDiscovery(logger *logrus.Entry) ([][]*net.TCPAddr, error) {
_, addrs, err := netLookupSRV(srvService, srvProto, srvName)
if err != nil {
_, fallbackAddrs, fallbackErr := fallbackLookupSRV(srvService, srvProto, srvName)
if fallbackErr != nil || len(fallbackAddrs) == 0 {
// use the original DNS error `err` in messages, not `fallbackErr`
logger.Errorln("Error looking up Cloudflare edge IPs: the DNS query failed:", err)
for _, s := range friendlyDNSErrorLines {
logger.Errorln(s)
}
return nil, errors.Wrapf(err, "Could not lookup srv records on _%v._%v.%v", srvService, srvProto, srvName)
}
// Accept the fallback results and keep going
addrs = fallbackAddrs
}
var resolvedIPsPerCNAME [][]*net.TCPAddr
for _, addr := range addrs {
ips, err := resolveSRVToTCP(addr)
if err != nil {
return nil, err
}
resolvedIPsPerCNAME = append(resolvedIPsPerCNAME, ips)
}
return resolvedIPsPerCNAME, nil
}
func lookupSRVWithDOT(service, proto, name string) (cname string, addrs []*net.SRV, err error) {
// Inspiration: https://github.com/artyom/dot/blob/master/dot.go
r := &net.Resolver{
PreferGo: true,
Dial: func(ctx context.Context, _ string, _ string) (net.Conn, error) {
var dialer net.Dialer
conn, err := dialer.DialContext(ctx, "tcp", dotServerAddr)
if err != nil {
return nil, err
}
tlsConfig := &tls.Config{ServerName: dotServerName}
return tls.Client(conn, tlsConfig), nil
},
}
ctx, cancel := context.WithTimeout(context.Background(), dotTimeout)
defer cancel()
return r.LookupSRV(ctx, srvService, srvProto, srvName)
}
func resolveSRVToTCP(srv *net.SRV) ([]*net.TCPAddr, error) {
ips, err := netLookupIP(srv.Target)
if err != nil {
return nil, errors.Wrapf(err, "Couldn't resolve SRV record %v", srv)
}
if len(ips) == 0 {
return nil, fmt.Errorf("SRV record %v had no IPs", srv)
}
addrs := make([]*net.TCPAddr, len(ips))
for i, ip := range ips {
addrs[i] = &net.TCPAddr{IP: ip, Port: int(srv.Port)}
}
return addrs, nil
}
// EdgeHostnameResolver discovers the addresses of Cloudflare's edge network via a list of server hostnames.
// It implements EdgeServiceDiscoverer interface, and is used mainly for testing connectivity.
type EdgeHostnameResolver struct {
sync.Mutex
// hostnames of edge servers
hostnames []string
// Addrs to connect to cloudflare's edge network
addrs []*net.TCPAddr
// Addresses that are in active use.
// This is actually a set of net.TCPAddr's. We have to encode the keys
// with .String(), since net.TCPAddr contains a field of type net.IP and
// therefore it cannot be used as a map key
inUse map[string]*net.TCPAddr
// Addresses that were discarded due to a network error.
// Not sure what we'll do with these, but it feels good to keep them around for now.
bad []*net.TCPAddr
}
func NewEdgeHostnameResolver(edgeHostnames []string) (EdgeServiceDiscoverer, error) {
r := &EdgeHostnameResolver{
hostnames: edgeHostnames,
inUse: map[string]*net.TCPAddr{},
}
if err := r.Refresh(); err != nil {
return nil, err
}
return r, nil
}
func (r *EdgeHostnameResolver) Addr() (*net.TCPAddr, error) {
r.Lock()
defer r.Unlock()
if len(r.addrs) == 0 {
return nil, errors.New("No IP address to claim")
}
var addr *net.TCPAddr
addr, r.addrs = popAddr(r.addrs)
r.inUse[addr.String()] = addr
return addr, nil
}
func (r *EdgeHostnameResolver) AnyAddr() (*net.TCPAddr, error) {
r.Lock()
defer r.Unlock()
// return an unused addr
if len(r.addrs) > 0 {
return r.addrs[rand.Intn(len(r.addrs))], nil
}
// return an addr that's in use
for _, addr := range r.inUse {
return addr, nil
}
return nil, errors.New("No IP addresses")
}
func (r *EdgeHostnameResolver) ReplaceAddr(addr *net.TCPAddr) {
r.Lock()
defer r.Unlock()
delete(r.inUse, addr.String())
r.addrs = append(r.addrs, addr)
}
func (r *EdgeHostnameResolver) MarkAddrBad(addr *net.TCPAddr) {
r.Lock()
defer r.Unlock()
delete(r.inUse, addr.String())
r.bad = append(r.bad, addr)
}
func (r *EdgeHostnameResolver) AvailableAddrs() int {
r.Lock()
defer r.Unlock()
return len(r.addrs)
}
func (r *EdgeHostnameResolver) Refresh() error {
newAddrs, err := ResolveAddrs(r.hostnames)
if err != nil {
return err
}
r.Lock()
defer r.Unlock()
var notInUse []*net.TCPAddr
for _, newAddr := range newAddrs {
if _, ok := r.inUse[newAddr.String()]; !ok {
notInUse = append(notInUse, newAddr)
}
}
r.addrs = notInUse
r.bad = nil
return nil
}
// Resolve TCP address given a list of addresses. Address can be a hostname, however, it will return at most one
// of the hostname's IP addresses
func ResolveAddrs(addrs []string) ([]*net.TCPAddr, error) {
var tcpAddrs []*net.TCPAddr
for _, addr := range addrs {
tcpAddr, err := net.ResolveTCPAddr("tcp", addr)
if err != nil {
return nil, err
}
tcpAddrs = append(tcpAddrs, tcpAddr)
}
return tcpAddrs, nil
}
// Compute total set of IP addresses in use. This is useful if the regions
// are returned in a different order, or if an IP address is assigned to
// a different region for some reasion.
func allInUse(regions []*region) map[string]*net.TCPAddr {
result := make(map[string]*net.TCPAddr)
for _, region := range regions {
for k, v := range region.inUse {
result[k] = v
}
}
return result
}
func makeHARegions(addrLists [][]*net.TCPAddr, inUse map[string]*net.TCPAddr) (regions []*region) {
for _, addrList := range addrLists {
region := &region{inUse: map[string]*net.TCPAddr{}}
for _, addr := range addrList {
addrString := addr.String()
// No matter what region `addr` used to belong to, it's now a part
// of this region, so add it to this region's `inUse` map.
if _, ok := inUse[addrString]; ok {
region.inUse[addrString] = addr
} else {
region.addrs = append(region.addrs, addr)
}
}
regions = append(regions, region)
}
return
}
func popAddr(addrs []*net.TCPAddr) (*net.TCPAddr, []*net.TCPAddr) {
first := addrs[0]
addrs[0] = nil // prevent memory leak
addrs = addrs[1:]
return first, addrs
}

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@ -1,317 +0,0 @@
package connection
import (
"net"
"sync"
"testing"
"testing/quick"
"time"
"github.com/sirupsen/logrus"
"github.com/stretchr/testify/assert"
)
func TestEdgeDiscovery(t *testing.T) {
mockAddrs := newMockAddrs(19, 2, 5)
netLookupSRV = mockNetLookupSRV(mockAddrs)
netLookupIP = mockNetLookupIP(mockAddrs)
expectedAddrSet := map[string]bool{}
for _, addrs := range mockAddrs.addrMap {
for _, addr := range addrs {
expectedAddrSet[addr.String()] = true
}
}
addrLists, err := EdgeDiscovery(logrus.New().WithFields(logrus.Fields{}))
assert.NoError(t, err)
actualAddrSet := map[string]bool{}
for _, addrs := range addrLists {
for _, addr := range addrs {
actualAddrSet[addr.String()] = true
}
}
assert.Equal(t, expectedAddrSet, actualAddrSet)
}
func TestAllInUse(t *testing.T) {
for _, testCase := range []struct {
regions []*region
expected map[string]*net.TCPAddr
}{
{
regions: nil,
expected: map[string]*net.TCPAddr{},
},
{
regions: []*region{
&region{inUse: map[string]*net.TCPAddr{}},
&region{inUse: map[string]*net.TCPAddr{}},
},
expected: map[string]*net.TCPAddr{},
},
{
regions: []*region{
&region{inUse: map[string]*net.TCPAddr{":1": &net.TCPAddr{Port: 1}}},
&region{inUse: map[string]*net.TCPAddr{":4": &net.TCPAddr{Port: 4}}},
},
expected: map[string]*net.TCPAddr{":1": &net.TCPAddr{Port: 1}, ":4": &net.TCPAddr{Port: 4}},
},
} {
actual := allInUse(testCase.regions)
assert.Equal(t, testCase.expected, actual)
}
}
func TestMakeRegions(t *testing.T) {
for _, testCase := range []struct {
addrList [][]*net.TCPAddr
inUse map[string]*net.TCPAddr
expected []*region
}{
{
addrList: [][]*net.TCPAddr{},
expected: nil,
},
{
addrList: [][]*net.TCPAddr{
[]*net.TCPAddr{&net.TCPAddr{Port: 1}, &net.TCPAddr{Port: 2}},
},
expected: []*region{
&region{addrs: []*net.TCPAddr{&net.TCPAddr{Port: 1}, &net.TCPAddr{Port: 2}}, inUse: map[string]*net.TCPAddr{}},
},
},
{
addrList: [][]*net.TCPAddr{
[]*net.TCPAddr{&net.TCPAddr{Port: 1}, &net.TCPAddr{Port: 2}},
[]*net.TCPAddr{&net.TCPAddr{Port: 3}, &net.TCPAddr{Port: 4}},
},
expected: []*region{
&region{addrs: []*net.TCPAddr{&net.TCPAddr{Port: 1}, &net.TCPAddr{Port: 2}}, inUse: map[string]*net.TCPAddr{}},
&region{addrs: []*net.TCPAddr{&net.TCPAddr{Port: 3}, &net.TCPAddr{Port: 4}}, inUse: map[string]*net.TCPAddr{}},
},
},
{
addrList: [][]*net.TCPAddr{
[]*net.TCPAddr{&net.TCPAddr{Port: 1}, &net.TCPAddr{Port: 2}},
[]*net.TCPAddr{&net.TCPAddr{Port: 3}, &net.TCPAddr{Port: 4}},
},
inUse: map[string]*net.TCPAddr{
":1": &net.TCPAddr{Port: 1},
":4": &net.TCPAddr{Port: 4},
},
expected: []*region{
&region{addrs: []*net.TCPAddr{&net.TCPAddr{Port: 2}}, inUse: map[string]*net.TCPAddr{":1": &net.TCPAddr{Port: 1}}},
&region{addrs: []*net.TCPAddr{&net.TCPAddr{Port: 3}}, inUse: map[string]*net.TCPAddr{":4": &net.TCPAddr{Port: 4}}},
},
},
} {
actual := makeHARegions(testCase.addrList, testCase.inUse)
assert.Equal(t, testCase.expected, actual)
}
}
func assertIsBalanced(t *testing.T, regions []*region) bool {
// Compute max(len(region.addrs) for region in regions)
// No region should have significantly fewer addresses than this
var longestAddrs int
{
longestAddrs = 0
for _, region := range regions {
if l := len(region.addrs); l > longestAddrs {
longestAddrs = l
}
}
}
for _, region := range regions {
if len(region.addrs) == longestAddrs || len(region.addrs) == longestAddrs-1 {
continue
}
return assert.Fail(t,
"found a region with %v free addrs, while the longest addrs list is %v",
len(region.addrs), longestAddrs)
}
return true
}
// Various end-to-end tests, run with quickcheck (i.e. the testing/quick package)
func TestEdgeAddrResolver(t *testing.T) {
concurrentReplacement := func(mockAddrs mockAddrs) bool {
netLookupSRV = mockNetLookupSRV(mockAddrs)
netLookupIP = mockNetLookupIP(mockAddrs)
resolver, err := NewEdgeAddrResolver(logrus.New())
if !assert.NoError(t, err) {
return false
}
assert.Equal(t, mockAddrs.numAddrs, resolver.AvailableAddrs(),
"every address should be initially available")
// Create several goroutines to simulate HA connections that acquire
// and replace IP addresses.
var wg sync.WaitGroup
wg.Add(mockAddrs.numAddrs)
for i := 0; i < mockAddrs.numAddrs; i++ {
go func() {
defer wg.Done()
const reconnectionCount = 50
for i := 0; i < reconnectionCount; i++ {
if resolver.AvailableAddrs() == 0 {
err = resolver.Refresh()
assert.NoError(t, err)
}
addr, err := resolver.Addr()
if !assert.NoError(t, err) {
return
}
time.Sleep(0) // allow some other goroutine to run
resolver.ReplaceAddr(addr)
time.Sleep(0) // allow some other goroutine to run
}
}()
}
wg.Wait()
assert.Equal(t, mockAddrs.numAddrs, resolver.AvailableAddrs(),
"every address should be available after replacement")
return !t.Failed()
}
badAddrWithRefresh := func(mockAddrs mockAddrs) bool {
netLookupSRV = mockNetLookupSRV(mockAddrs)
netLookupIP = mockNetLookupIP(mockAddrs)
resolver, err := NewEdgeAddrResolver(logrus.New())
if !assert.NoError(t, err) {
return false
}
assert.Equal(t, mockAddrs.numAddrs, resolver.AvailableAddrs(),
"every address should be initially available")
var addrs []*net.TCPAddr
for i := 0; i < mockAddrs.numAddrs; i++ {
assert.Equal(t, mockAddrs.numAddrs-i, resolver.AvailableAddrs())
addr, err := resolver.Addr()
assert.NoError(t, err)
addrs = append(addrs, addr)
}
assert.Equal(t, 0, resolver.AvailableAddrs(), "all addresses should have been taken")
_, err = resolver.Addr()
assert.Error(t, err)
anyAddr, err := resolver.AnyAddr()
assert.NoError(t, err, "should still be okay to call AnyAddr")
resolver.MarkAddrBad(anyAddr)
assert.Equal(t, 0, resolver.AvailableAddrs(), "all addresses should still be used")
_, err = resolver.Addr()
assert.Error(t, err, "all addresses should still be used")
err = resolver.Refresh()
assert.NoError(t, err, "Refresh() should have worked")
assert.Equal(t, 1, resolver.AvailableAddrs(),
"Refresh() should have reset the state of the 'bad' address")
addr, err := resolver.Addr()
assert.NoError(t, err)
assert.Equal(t, anyAddr, addr)
_, err = resolver.Addr()
assert.Error(t, err, "all addresses should be used again")
return !t.Failed()
}
assert.NoError(t, quick.Check(concurrentReplacement, nil))
assert.NoError(t, quick.Check(badAddrWithRefresh, nil))
}
// "White-box" test: runs Addr() and checks internal state
func TestEdgeAddrResolver_Addr(t *testing.T) {
e := &EdgeAddrResolver{regions: nil}
addr, err := e.Addr()
assert.Error(t, err)
testRegions := func() []*region {
return []*region{
&region{addrs: []*net.TCPAddr{&net.TCPAddr{Port: 1}}, inUse: map[string]*net.TCPAddr{":2": &net.TCPAddr{Port: 2}, ":3": &net.TCPAddr{Port: 3}}},
&region{addrs: []*net.TCPAddr{&net.TCPAddr{Port: 4}, &net.TCPAddr{Port: 5}}, inUse: map[string]*net.TCPAddr{":6": &net.TCPAddr{Port: 6}}},
&region{addrs: []*net.TCPAddr{&net.TCPAddr{Port: 7}, &net.TCPAddr{Port: 8}}, inUse: map[string]*net.TCPAddr{":9": &net.TCPAddr{Port: 9}}},
}
}
e = &EdgeAddrResolver{regions: testRegions()}
addr, err = e.Addr()
assert.NoError(t, err)
assert.Equal(t, &net.TCPAddr{Port: 4}, addr)
var expected []*region
{
expected = testRegions()
expected[1].addrs = expected[1].addrs[1:]
expected[1].inUse[":4"] = &net.TCPAddr{Port: 4}
}
assert.Equal(t, expected, e.regions)
}
// "White-box" test: runs AnyAddr() and checks internal state
func TestEdgeAddrResolver_AnyAddr(t *testing.T) {
e := &EdgeAddrResolver{regions: nil}
addr, err := e.AnyAddr()
assert.Error(t, err)
e = &EdgeAddrResolver{regions: []*region{&region{addrs: []*net.TCPAddr{&net.TCPAddr{Port: 1}}, inUse: map[string]*net.TCPAddr{":2": &net.TCPAddr{Port: 2}}}}}
addr, err = e.AnyAddr()
assert.NoError(t, err)
assert.Equal(t, &net.TCPAddr{Port: 1}, addr, "should have chosen the inactive address")
e = &EdgeAddrResolver{regions: []*region{&region{inUse: map[string]*net.TCPAddr{":1": &net.TCPAddr{Port: 1}}}}}
addr, err = e.AnyAddr()
assert.NoError(t, err)
assert.Equal(t, &net.TCPAddr{Port: 1}, addr, "should have chosen an active address rather than nothing")
}
// "White-box" test: runs ReplaceAddr() and checks internal state
func TestEdgeAddrResolver_ReplaceAddr(t *testing.T) {
e := &EdgeAddrResolver{regions: nil}
e.ReplaceAddr(&net.TCPAddr{Port: 1}) // this shouldn't panic, I guess
testRegions := func() []*region {
return []*region{
&region{addrs: []*net.TCPAddr{&net.TCPAddr{Port: 1}}, inUse: map[string]*net.TCPAddr{":2": &net.TCPAddr{Port: 2}, ":3": &net.TCPAddr{Port: 3}}},
&region{addrs: []*net.TCPAddr{&net.TCPAddr{Port: 4}, &net.TCPAddr{Port: 5}}, inUse: map[string]*net.TCPAddr{":6": &net.TCPAddr{Port: 6}}},
&region{addrs: []*net.TCPAddr{&net.TCPAddr{Port: 7}, &net.TCPAddr{Port: 8}}, inUse: map[string]*net.TCPAddr{":9": &net.TCPAddr{Port: 9}}},
}
}
e = &EdgeAddrResolver{regions: testRegions()}
e.ReplaceAddr(&net.TCPAddr{Port: 6})
var expected []*region
{
expected = testRegions()
delete(expected[1].inUse, ":6")
expected[1].addrs = append(expected[1].addrs, &net.TCPAddr{Port: 6})
}
assert.Equal(t, expected, e.regions)
}
// "White-box" test: runs MarkAddrBad() and checks internal state
func TestEdgeAddrResolver_MarkAddrBad(t *testing.T) {
e := &EdgeAddrResolver{regions: nil}
e.ReplaceAddr(&net.TCPAddr{Port: 1}) // this shouldn't panic, I guess
testRegions := func() []*region {
return []*region{
&region{addrs: []*net.TCPAddr{&net.TCPAddr{Port: 1}}, inUse: map[string]*net.TCPAddr{":2": &net.TCPAddr{Port: 2}, ":3": &net.TCPAddr{Port: 3}}},
&region{addrs: []*net.TCPAddr{&net.TCPAddr{Port: 4}, &net.TCPAddr{Port: 5}}, inUse: map[string]*net.TCPAddr{":6": &net.TCPAddr{Port: 6}}},
&region{addrs: []*net.TCPAddr{&net.TCPAddr{Port: 7}, &net.TCPAddr{Port: 8}}, inUse: map[string]*net.TCPAddr{":9": &net.TCPAddr{Port: 9}}},
}
}
e = &EdgeAddrResolver{regions: testRegions()}
e.MarkAddrBad(&net.TCPAddr{Port: 6})
var expected []*region
{
expected = testRegions()
delete(expected[1].inUse, ":6")
expected[1].bad = append(expected[1].bad, &net.TCPAddr{Port: 6})
}
assert.Equal(t, expected, e.regions)
}

View File

@ -13,6 +13,7 @@ import (
"github.com/sirupsen/logrus"
"github.com/cloudflare/cloudflared/cmd/cloudflared/buildinfo"
"github.com/cloudflare/cloudflared/edgediscovery"
"github.com/cloudflare/cloudflared/h2mux"
"github.com/cloudflare/cloudflared/streamhandler"
tunnelpogs "github.com/cloudflare/cloudflared/tunnelrpc/pogs"
@ -35,7 +36,7 @@ type EdgeManager struct {
// cloudflaredConfig is the cloudflared configuration that is determined when the process first starts
cloudflaredConfig *CloudflaredConfig
// serviceDiscoverer returns the next edge addr to connect to
serviceDiscoverer EdgeServiceDiscoverer
serviceDiscoverer *edgediscovery.Edge
// state is attributes of ConnectionManager that can change during runtime.
state *edgeManagerState
@ -73,7 +74,7 @@ func NewEdgeManager(
edgeConnMgrConfigurable *EdgeManagerConfigurable,
userCredential []byte,
tlsConfig *tls.Config,
serviceDiscoverer EdgeServiceDiscoverer,
serviceDiscoverer *edgediscovery.Edge,
cloudflaredConfig *CloudflaredConfig,
logger *logrus.Logger,
) *EdgeManager {
@ -91,27 +92,29 @@ func NewEdgeManager(
func (em *EdgeManager) Run(ctx context.Context) error {
defer em.shutdown()
resolveEdgeIPTicker := time.Tick(resolveEdgeAddrTTL)
// Currently, declarative tunnels don't have any concept of a stable connection
// Each edge connection is transient and when it dies, it is replaced by a different one,
// not restarted.
// So in the future we should really change this so that n connections are stored individually
connIndex := 0
for {
select {
case <-ctx.Done():
return errors.Wrap(ctx.Err(), "EdgeConnectionManager terminated")
case <-resolveEdgeIPTicker:
if err := em.serviceDiscoverer.Refresh(); err != nil {
em.logger.WithError(err).Warn("Cannot refresh Cloudflare edge addresses")
}
default:
time.Sleep(1 * time.Second)
}
// Create/delete connection one at a time, so we don't need to adjust for connections that are being created/deleted
// in shouldCreateConnection or shouldReduceConnection calculation
if em.state.shouldCreateConnection(em.serviceDiscoverer.AvailableAddrs()) {
if connErr := em.newConnection(ctx); connErr != nil {
if connErr := em.newConnection(ctx, connIndex); connErr != nil {
if !connErr.ShouldRetry {
em.logger.WithError(connErr).Error(em.noRetryMessage())
return connErr
}
em.logger.WithError(connErr).Error("cannot create new connection")
} else {
connIndex++
}
} else if em.state.shouldReduceConnection() {
if err := em.closeConnection(ctx); err != nil {
@ -126,8 +129,8 @@ func (em *EdgeManager) UpdateConfigurable(newConfigurable *EdgeManagerConfigurab
em.state.updateConfigurable(newConfigurable)
}
func (em *EdgeManager) newConnection(ctx context.Context) *tunnelpogs.ConnectError {
edgeTCPAddr, err := em.serviceDiscoverer.Addr()
func (em *EdgeManager) newConnection(ctx context.Context, index int) *tunnelpogs.ConnectError {
edgeTCPAddr, err := em.serviceDiscoverer.GetAddr(index)
if err != nil {
return retryConnection(fmt.Sprintf("edge address discovery error: %v", err))
}
@ -197,7 +200,7 @@ func (em *EdgeManager) serveConn(ctx context.Context, conn *Connection) {
err := conn.Serve(ctx)
em.logger.WithError(err).Warn("Connection closed")
em.state.closeConnection(conn)
em.serviceDiscoverer.ReplaceAddr(conn.addr)
em.serviceDiscoverer.GiveBack(conn.addr)
}
func (em *EdgeManager) noRetryMessage() string {

View File

@ -1,6 +1,7 @@
package connection
import (
"net"
"testing"
"time"
@ -8,8 +9,8 @@ import (
"github.com/sirupsen/logrus"
"github.com/stretchr/testify/assert"
"github.com/cloudflare/cloudflared/cmd/cloudflared/buildinfo"
"github.com/cloudflare/cloudflared/edgediscovery"
"github.com/cloudflare/cloudflared/h2mux"
"github.com/cloudflare/cloudflared/streamhandler"
"github.com/cloudflare/cloudflared/tunnelrpc/pogs"
@ -48,14 +49,15 @@ func mockEdgeManager() *EdgeManager {
newConfigChan := make(chan<- *pogs.ClientConfig)
useConfigResultChan := make(<-chan *pogs.UseConfigurationResult)
logger := logrus.New()
edge := edgediscovery.MockEdge(logger, []*net.TCPAddr{})
return NewEdgeManager(
streamhandler.NewStreamHandler(newConfigChan, useConfigResultChan, logger),
configurable,
[]byte{},
nil,
&mockEdgeServiceDiscoverer{},
edge,
cloudflaredConfig,
logrus.New(),
logger,
)
}

View File

@ -0,0 +1,135 @@
package allregions
import (
"context"
"crypto/tls"
"fmt"
"net"
"time"
"github.com/pkg/errors"
"github.com/sirupsen/logrus"
)
const (
// Used to discover HA origintunneld servers
srvService = "origintunneld"
srvProto = "tcp"
srvName = "argotunnel.com"
// Used to fallback to DoT when we can't use the default resolver to
// discover HA origintunneld servers (GitHub issue #75).
dotServerName = "cloudflare-dns.com"
dotServerAddr = "1.1.1.1:853"
dotTimeout = time.Duration(15 * time.Second)
// SRV record resolution TTL
resolveEdgeAddrTTL = 1 * time.Hour
subsystemEdgeAddrResolver = "edgeAddrResolver"
)
// Redeclare network functions so they can be overridden in tests.
var (
netLookupSRV = net.LookupSRV
netLookupIP = net.LookupIP
)
// If the call to net.LookupSRV fails, try to fall back to DoT from Cloudflare directly.
//
// Note: Instead of DoT, we could also have used DoH. Either of these:
// - directly via the JSON API (https://1.1.1.1/dns-query?ct=application/dns-json&name=_origintunneld._tcp.argotunnel.com&type=srv)
// - indirectly via `tunneldns.NewUpstreamHTTPS()`
// But both of these cases miss out on a key feature from the stdlib:
// "The returned records are sorted by priority and randomized by weight within a priority."
// (https://golang.org/pkg/net/#Resolver.LookupSRV)
// Does this matter? I don't know. It may someday. Let's use DoT so we don't need to worry about it.
// See also: Go feature request for stdlib-supported DoH: https://github.com/golang/go/issues/27552
var fallbackLookupSRV = lookupSRVWithDOT
var friendlyDNSErrorLines = []string{
`Please try the following things to diagnose this issue:`,
` 1. ensure that argotunnel.com is returning "origintunneld" service records.`,
` Run your system's equivalent of: dig srv _origintunneld._tcp.argotunnel.com`,
` 2. ensure that your DNS resolver is not returning compressed SRV records.`,
` See GitHub issue https://github.com/golang/go/issues/27546`,
` For example, you could use Cloudflare's 1.1.1.1 as your resolver:`,
` https://developers.cloudflare.com/1.1.1.1/setting-up-1.1.1.1/`,
}
// EdgeDiscovery implements HA service discovery lookup.
func edgeDiscovery(logger *logrus.Entry) ([][]*net.TCPAddr, error) {
_, addrs, err := netLookupSRV(srvService, srvProto, srvName)
if err != nil {
_, fallbackAddrs, fallbackErr := fallbackLookupSRV(srvService, srvProto, srvName)
if fallbackErr != nil || len(fallbackAddrs) == 0 {
// use the original DNS error `err` in messages, not `fallbackErr`
logger.Errorln("Error looking up Cloudflare edge IPs: the DNS query failed:", err)
for _, s := range friendlyDNSErrorLines {
logger.Errorln(s)
}
return nil, errors.Wrapf(err, "Could not lookup srv records on _%v._%v.%v", srvService, srvProto, srvName)
}
// Accept the fallback results and keep going
addrs = fallbackAddrs
}
var resolvedIPsPerCNAME [][]*net.TCPAddr
for _, addr := range addrs {
ips, err := resolveSRVToTCP(addr)
if err != nil {
return nil, err
}
resolvedIPsPerCNAME = append(resolvedIPsPerCNAME, ips)
}
return resolvedIPsPerCNAME, nil
}
func lookupSRVWithDOT(service, proto, name string) (cname string, addrs []*net.SRV, err error) {
// Inspiration: https://github.com/artyom/dot/blob/master/dot.go
r := &net.Resolver{
PreferGo: true,
Dial: func(ctx context.Context, _ string, _ string) (net.Conn, error) {
var dialer net.Dialer
conn, err := dialer.DialContext(ctx, "tcp", dotServerAddr)
if err != nil {
return nil, err
}
tlsConfig := &tls.Config{ServerName: dotServerName}
return tls.Client(conn, tlsConfig), nil
},
}
ctx, cancel := context.WithTimeout(context.Background(), dotTimeout)
defer cancel()
return r.LookupSRV(ctx, srvService, srvProto, srvName)
}
func resolveSRVToTCP(srv *net.SRV) ([]*net.TCPAddr, error) {
ips, err := netLookupIP(srv.Target)
if err != nil {
return nil, errors.Wrapf(err, "Couldn't resolve SRV record %v", srv)
}
if len(ips) == 0 {
return nil, fmt.Errorf("SRV record %v had no IPs", srv)
}
addrs := make([]*net.TCPAddr, len(ips))
for i, ip := range ips {
addrs[i] = &net.TCPAddr{IP: ip, Port: int(srv.Port)}
}
return addrs, nil
}
// ResolveAddrs resolves TCP address given a list of addresses. Address can be a hostname, however, it will return at most one
// of the hostname's IP addresses
func ResolveAddrs(addrs []string) ([]*net.TCPAddr, error) {
var tcpAddrs []*net.TCPAddr
for _, addr := range addrs {
tcpAddr, err := net.ResolveTCPAddr("tcp", addr)
if err != nil {
return nil, err
}
tcpAddrs = append(tcpAddrs, tcpAddr)
}
return tcpAddrs, nil
}

View File

@ -0,0 +1,32 @@
package allregions
import (
"testing"
"github.com/sirupsen/logrus"
"github.com/stretchr/testify/assert"
)
func TestEdgeDiscovery(t *testing.T) {
mockAddrs := newMockAddrs(19, 2, 5)
netLookupSRV = mockNetLookupSRV(mockAddrs)
netLookupIP = mockNetLookupIP(mockAddrs)
expectedAddrSet := map[string]bool{}
for _, addrs := range mockAddrs.addrMap {
for _, addr := range addrs {
expectedAddrSet[addr.String()] = true
}
}
addrLists, err := edgeDiscovery(logrus.New().WithFields(logrus.Fields{}))
assert.NoError(t, err)
actualAddrSet := map[string]bool{}
for _, addrs := range addrLists {
for _, addr := range addrs {
actualAddrSet[addr.String()] = true
}
}
assert.Equal(t, expectedAddrSet, actualAddrSet)
}

View File

@ -0,0 +1,89 @@
package allregions
import (
"fmt"
"math"
"math/rand"
"net"
"reflect"
"testing/quick"
)
type mockAddrs struct {
// a set of synthetic SRV records
addrMap map[net.SRV][]*net.TCPAddr
// the total number of addresses, aggregated across addrMap.
// For the convenience of test code that would otherwise have to compute
// this by hand every time.
numAddrs int
}
func newMockAddrs(port uint16, numRegions uint8, numAddrsPerRegion uint8) mockAddrs {
addrMap := make(map[net.SRV][]*net.TCPAddr)
numAddrs := 0
for r := uint8(0); r < numRegions; r++ {
var (
srv = net.SRV{Target: fmt.Sprintf("test-region-%v.example.com", r), Port: port}
addrs []*net.TCPAddr
)
for a := uint8(0); a < numAddrsPerRegion; a++ {
addrs = append(addrs, &net.TCPAddr{
IP: net.ParseIP(fmt.Sprintf("10.0.%v.%v", r, a)),
Port: int(port),
})
}
addrMap[srv] = addrs
numAddrs += len(addrs)
}
return mockAddrs{addrMap: addrMap, numAddrs: numAddrs}
}
var _ quick.Generator = mockAddrs{}
func (mockAddrs) Generate(rand *rand.Rand, size int) reflect.Value {
port := uint16(rand.Intn(math.MaxUint16))
numRegions := uint8(1 + rand.Intn(10))
numAddrsPerRegion := uint8(1 + rand.Intn(32))
result := newMockAddrs(port, numRegions, numAddrsPerRegion)
return reflect.ValueOf(result)
}
// Returns a function compatible with net.LookupSRV that will return the SRV
// records from mockAddrs.
func mockNetLookupSRV(
m mockAddrs,
) func(service, proto, name string) (cname string, addrs []*net.SRV, err error) {
var addrs []*net.SRV
for k := range m.addrMap {
addr := k
addrs = append(addrs, &addr)
// We can't just do
// addrs = append(addrs, &k)
// `k` will be reused by subsequent loop iterations,
// so all the copies of `&k` would point to the same location.
}
return func(_, _, _ string) (string, []*net.SRV, error) {
return "", addrs, nil
}
}
// Returns a function compatible with net.LookupIP that translates the SRV records
// from mockAddrs into IP addresses, based on the TCP addresses in mockAddrs.
func mockNetLookupIP(
m mockAddrs,
) func(host string) ([]net.IP, error) {
return func(host string) ([]net.IP, error) {
for srv, tcpAddrs := range m.addrMap {
if srv.Target != host {
continue
}
result := make([]net.IP, len(tcpAddrs))
for i, tcpAddr := range tcpAddrs {
result[i] = tcpAddr.IP
}
return result, nil
}
return nil, fmt.Errorf("No IPs for %v", host)
}
}

View File

@ -0,0 +1,78 @@
package allregions
import (
"net"
)
// Region contains cloudflared edge addresses. The edge is partitioned into several regions for
// redundancy purposes.
type Region struct {
connFor map[*net.TCPAddr]UsedBy
}
// NewRegion creates a region with the given addresses, which are all unused.
func NewRegion(addrs []*net.TCPAddr) Region {
// The zero value of UsedBy is Unused(), so we can just initialize the map's values with their
// zero values.
m := make(map[*net.TCPAddr]UsedBy)
for _, addr := range addrs {
m[addr] = Unused()
}
return Region{connFor: m}
}
// AddrUsedBy finds the address used by the given connection in this region.
// Returns nil if the connection isn't using any IP.
func (r *Region) AddrUsedBy(connID int) *net.TCPAddr {
for addr, used := range r.connFor {
if used.Used && used.ConnID == connID {
return addr
}
}
return nil
}
// AvailableAddrs counts how many unused addresses this region contains.
func (r Region) AvailableAddrs() int {
n := 0
for _, usedby := range r.connFor {
if !usedby.Used {
n++
}
}
return n
}
// GetUnusedIP returns a random unused address in this region.
// Returns nil if all addresses are in use.
func (r Region) GetUnusedIP(excluding *net.TCPAddr) *net.TCPAddr {
for addr, usedby := range r.connFor {
if !usedby.Used && addr != excluding {
return addr
}
}
return nil
}
// Use the address, assigning it to a proxy connection.
func (r Region) Use(addr *net.TCPAddr, connID int) {
r.connFor[addr] = InUse(connID)
}
// GetAnyAddress returns an arbitrary address from the region.
func (r Region) GetAnyAddress() *net.TCPAddr {
for addr := range r.connFor {
return addr
}
return nil
}
// GiveBack the address, ensuring it is no longer assigned to an IP.
// Returns true if the address is in this region.
func (r Region) GiveBack(addr *net.TCPAddr) (ok bool) {
if _, ok := r.connFor[addr]; !ok {
return false
}
r.connFor[addr] = Unused()
return true
}

View File

@ -0,0 +1,287 @@
package allregions
import (
"fmt"
"net"
"reflect"
"testing"
)
func TestRegion_New(t *testing.T) {
r := NewRegion([]*net.TCPAddr{&addr0, &addr1, &addr2})
fmt.Println(r.connFor)
if r.AvailableAddrs() != 3 {
t.Errorf("r.AvailableAddrs() == %v but want 3", r.AvailableAddrs())
}
}
func TestRegion_AddrUsedBy(t *testing.T) {
type fields struct {
connFor map[*net.TCPAddr]UsedBy
}
type args struct {
connID int
}
tests := []struct {
name string
fields fields
args args
want *net.TCPAddr
}{
{
name: "happy trivial test",
fields: fields{connFor: map[*net.TCPAddr]UsedBy{
&addr0: InUse(0),
}},
args: args{connID: 0},
want: &addr0,
},
{
name: "sad trivial test",
fields: fields{connFor: map[*net.TCPAddr]UsedBy{
&addr0: InUse(0),
}},
args: args{connID: 1},
want: nil,
},
{
name: "sad test",
fields: fields{connFor: map[*net.TCPAddr]UsedBy{
&addr0: InUse(0),
&addr1: InUse(1),
&addr2: InUse(2),
}},
args: args{connID: 3},
want: nil,
},
{
name: "happy test",
fields: fields{connFor: map[*net.TCPAddr]UsedBy{
&addr0: InUse(0),
&addr1: InUse(1),
&addr2: InUse(2),
}},
args: args{connID: 1},
want: &addr1,
},
}
for _, tt := range tests {
t.Run(tt.name, func(t *testing.T) {
r := &Region{
connFor: tt.fields.connFor,
}
if got := r.AddrUsedBy(tt.args.connID); !reflect.DeepEqual(got, tt.want) {
t.Errorf("Region.AddrUsedBy() = %v, want %v", got, tt.want)
}
})
}
}
func TestRegion_AvailableAddrs(t *testing.T) {
type fields struct {
connFor map[*net.TCPAddr]UsedBy
}
tests := []struct {
name string
fields fields
want int
}{
{
name: "contains addresses",
fields: fields{connFor: map[*net.TCPAddr]UsedBy{
&addr0: InUse(0),
&addr1: Unused(),
&addr2: InUse(2),
}},
want: 1,
},
{
name: "all free",
fields: fields{connFor: map[*net.TCPAddr]UsedBy{
&addr0: Unused(),
&addr1: Unused(),
&addr2: Unused(),
}},
want: 3,
},
{
name: "all used",
fields: fields{connFor: map[*net.TCPAddr]UsedBy{
&addr0: InUse(0),
&addr1: InUse(1),
&addr2: InUse(2),
}},
want: 0,
},
{
name: "empty",
fields: fields{connFor: map[*net.TCPAddr]UsedBy{}},
want: 0,
},
}
for _, tt := range tests {
t.Run(tt.name, func(t *testing.T) {
r := Region{
connFor: tt.fields.connFor,
}
if got := r.AvailableAddrs(); got != tt.want {
t.Errorf("Region.AvailableAddrs() = %v, want %v", got, tt.want)
}
})
}
}
func TestRegion_GetUnusedIP(t *testing.T) {
type fields struct {
connFor map[*net.TCPAddr]UsedBy
}
type args struct {
excluding *net.TCPAddr
}
tests := []struct {
name string
fields fields
args args
want *net.TCPAddr
}{
{
name: "happy test with excluding set",
fields: fields{connFor: map[*net.TCPAddr]UsedBy{
&addr0: Unused(),
&addr1: Unused(),
&addr2: InUse(2),
}},
args: args{excluding: &addr0},
want: &addr1,
},
{
name: "happy test with no excluding",
fields: fields{connFor: map[*net.TCPAddr]UsedBy{
&addr0: InUse(0),
&addr1: Unused(),
&addr2: InUse(2),
}},
args: args{excluding: nil},
want: &addr1,
},
{
name: "sad test with no excluding",
fields: fields{connFor: map[*net.TCPAddr]UsedBy{
&addr0: InUse(0),
&addr1: InUse(1),
&addr2: InUse(2),
}},
args: args{excluding: nil},
want: nil,
},
{
name: "sad test with excluding",
fields: fields{connFor: map[*net.TCPAddr]UsedBy{
&addr0: Unused(),
&addr1: InUse(1),
&addr2: InUse(2),
}},
args: args{excluding: &addr0},
want: nil,
},
}
for _, tt := range tests {
t.Run(tt.name, func(t *testing.T) {
r := Region{
connFor: tt.fields.connFor,
}
if got := r.GetUnusedIP(tt.args.excluding); !reflect.DeepEqual(got, tt.want) {
t.Errorf("Region.GetUnusedIP() = %v, want %v", got, tt.want)
}
})
}
}
func TestRegion_GiveBack(t *testing.T) {
type fields struct {
connFor map[*net.TCPAddr]UsedBy
}
type args struct {
addr *net.TCPAddr
}
tests := []struct {
name string
fields fields
args args
wantOk bool
availableAfter int
}{
{
name: "sad test with excluding",
fields: fields{connFor: map[*net.TCPAddr]UsedBy{
&addr1: InUse(1),
}},
args: args{addr: &addr1},
wantOk: true,
availableAfter: 1,
},
{
name: "sad test with excluding",
fields: fields{connFor: map[*net.TCPAddr]UsedBy{
&addr1: InUse(1),
}},
args: args{addr: &addr2},
wantOk: false,
availableAfter: 0,
},
}
for _, tt := range tests {
t.Run(tt.name, func(t *testing.T) {
r := Region{
connFor: tt.fields.connFor,
}
if gotOk := r.GiveBack(tt.args.addr); gotOk != tt.wantOk {
t.Errorf("Region.GiveBack() = %v, want %v", gotOk, tt.wantOk)
}
if tt.availableAfter != r.AvailableAddrs() {
t.Errorf("Region.AvailableAddrs() = %v, want %v", r.AvailableAddrs(), tt.availableAfter)
}
})
}
}
func TestRegion_GetAnyAddress(t *testing.T) {
type fields struct {
connFor map[*net.TCPAddr]UsedBy
}
tests := []struct {
name string
fields fields
wantNil bool
}{
{
name: "Sad test -- GetAnyAddress should only fail if the region is empty",
fields: fields{connFor: map[*net.TCPAddr]UsedBy{}},
wantNil: true,
},
{
name: "Happy test (all addresses unused)",
fields: fields{connFor: map[*net.TCPAddr]UsedBy{
&addr0: Unused(),
}},
wantNil: false,
},
{
name: "Happy test (GetAnyAddress can still return addresses used by proxy conns)",
fields: fields{connFor: map[*net.TCPAddr]UsedBy{
&addr0: InUse(2),
}},
wantNil: false,
},
}
for _, tt := range tests {
t.Run(tt.name, func(t *testing.T) {
r := Region{
connFor: tt.fields.connFor,
}
if got := r.GetAnyAddress(); tt.wantNil != (got == nil) {
t.Errorf("Region.GetAnyAddress() = %v, but should it return nil? %v", got, tt.wantNil)
}
})
}
}

View File

@ -0,0 +1,118 @@
package allregions
import (
"fmt"
"net"
"github.com/sirupsen/logrus"
)
// Regions stores Cloudflare edge network IPs, partitioned into two regions.
// This is NOT thread-safe. Users of this package should use it with a lock.
type Regions struct {
region1 Region
region2 Region
}
// ------------------------------------
// Constructors
// ------------------------------------
// ResolveEdge resolves the Cloudflare edge, returning all regions discovered.
func ResolveEdge(logger *logrus.Entry) (*Regions, error) {
addrLists, err := edgeDiscovery(logger)
if err != nil {
return nil, err
}
if len(addrLists) < 2 {
return nil, fmt.Errorf("expected at least 2 Cloudflare Regions regions, but SRV only returned %v", len(addrLists))
}
return &Regions{
region1: NewRegion(addrLists[0]),
region2: NewRegion(addrLists[1]),
}, nil
}
// StaticEdge creates a list of edge addresses from the list of hostnames.
// Mainly used for testing connectivity.
func StaticEdge(hostnames []string) (*Regions, error) {
addrs, err := ResolveAddrs(hostnames)
if err != nil {
return nil, err
}
return NewNoResolve(addrs), nil
}
// NewNoResolve doesn't resolve the edge. Instead it just uses the given addresses.
// You probably only need this for testing.
func NewNoResolve(addrs []*net.TCPAddr) *Regions {
region1 := make([]*net.TCPAddr, 0)
region2 := make([]*net.TCPAddr, 0)
for i, v := range addrs {
if i%2 == 0 {
region1 = append(region1, v)
} else {
region2 = append(region2, v)
}
}
return &Regions{
region1: NewRegion(region1),
region2: NewRegion(region2),
}
}
// ------------------------------------
// Methods
// ------------------------------------
// GetAnyAddress returns an arbitrary address from the larger region.
func (rs *Regions) GetAnyAddress() *net.TCPAddr {
if rs.region1.AvailableAddrs() > rs.region2.AvailableAddrs() {
return rs.region1.GetAnyAddress()
}
return rs.region2.GetAnyAddress()
}
// AddrUsedBy finds the address used by the given connection.
// Returns nil if the connection isn't using an address.
func (rs *Regions) AddrUsedBy(connID int) *net.TCPAddr {
if addr := rs.region1.AddrUsedBy(connID); addr != nil {
return addr
}
return rs.region2.AddrUsedBy(connID)
}
// GetUnusedAddr gets an unused addr from the edge, excluding the given addr. Prefer to use addresses
// evenly across both regions.
func (rs *Regions) GetUnusedAddr(excluding *net.TCPAddr, connID int) *net.TCPAddr {
var addr *net.TCPAddr
if rs.region1.AvailableAddrs() > rs.region2.AvailableAddrs() {
addr = rs.region1.GetUnusedIP(excluding)
rs.region1.Use(addr, connID)
} else {
addr = rs.region2.GetUnusedIP(excluding)
rs.region2.Use(addr, connID)
}
if addr == nil {
return nil
}
// Mark the address as used and return it
return addr
}
// AvailableAddrs returns how many edge addresses aren't used.
func (rs *Regions) AvailableAddrs() int {
return rs.region1.AvailableAddrs() + rs.region2.AvailableAddrs()
}
// GiveBack the address so that other connections can use it.
// Returns true if the address is in this edge.
func (rs *Regions) GiveBack(addr *net.TCPAddr) bool {
if found := rs.region1.GiveBack(addr); found {
return found
}
return rs.region2.GiveBack(addr)
}

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@ -0,0 +1,140 @@
package allregions
import (
"net"
"testing"
"github.com/stretchr/testify/assert"
)
var (
addr0 = net.TCPAddr{
IP: net.ParseIP("123.4.5.0"),
Port: 8000,
Zone: "",
}
addr1 = net.TCPAddr{
IP: net.ParseIP("123.4.5.1"),
Port: 8000,
Zone: "",
}
addr2 = net.TCPAddr{
IP: net.ParseIP("123.4.5.2"),
Port: 8000,
Zone: "",
}
addr3 = net.TCPAddr{
IP: net.ParseIP("123.4.5.3"),
Port: 8000,
Zone: "",
}
)
func makeRegions() Regions {
r1 := NewRegion([]*net.TCPAddr{&addr0, &addr1})
r2 := NewRegion([]*net.TCPAddr{&addr2, &addr3})
return Regions{region1: r1, region2: r2}
}
func TestRegions_AddrUsedBy(t *testing.T) {
rs := makeRegions()
addr1 := rs.GetUnusedAddr(nil, 1)
assert.Equal(t, addr1, rs.AddrUsedBy(1))
addr2 := rs.GetUnusedAddr(nil, 2)
assert.Equal(t, addr2, rs.AddrUsedBy(2))
addr3 := rs.GetUnusedAddr(nil, 3)
assert.Equal(t, addr3, rs.AddrUsedBy(3))
}
func TestRegions_Giveback_Region1(t *testing.T) {
rs := makeRegions()
rs.region1.Use(&addr0, 0)
rs.region1.Use(&addr1, 1)
rs.region2.Use(&addr2, 2)
rs.region2.Use(&addr3, 3)
assert.Equal(t, 0, rs.AvailableAddrs())
rs.GiveBack(&addr0)
assert.Equal(t, &addr0, rs.GetUnusedAddr(nil, 3))
}
func TestRegions_Giveback_Region2(t *testing.T) {
rs := makeRegions()
rs.region1.Use(&addr0, 0)
rs.region1.Use(&addr1, 1)
rs.region2.Use(&addr2, 2)
rs.region2.Use(&addr3, 3)
assert.Equal(t, 0, rs.AvailableAddrs())
rs.GiveBack(&addr2)
assert.Equal(t, &addr2, rs.GetUnusedAddr(nil, 2))
}
func TestRegions_GetUnusedAddr_OneAddrLeft(t *testing.T) {
rs := makeRegions()
rs.region1.Use(&addr0, 0)
rs.region1.Use(&addr1, 1)
rs.region2.Use(&addr2, 2)
assert.Equal(t, 1, rs.AvailableAddrs())
assert.Equal(t, &addr3, rs.GetUnusedAddr(nil, 3))
}
func TestRegions_GetUnusedAddr_Excluding_Region1(t *testing.T) {
rs := makeRegions()
rs.region1.Use(&addr0, 0)
rs.region1.Use(&addr1, 1)
assert.Equal(t, 2, rs.AvailableAddrs())
assert.Equal(t, &addr3, rs.GetUnusedAddr(&addr2, 3))
}
func TestRegions_GetUnusedAddr_Excluding_Region2(t *testing.T) {
rs := makeRegions()
rs.region2.Use(&addr2, 0)
rs.region2.Use(&addr3, 1)
assert.Equal(t, 2, rs.AvailableAddrs())
assert.Equal(t, &addr1, rs.GetUnusedAddr(&addr0, 1))
}
func TestNewNoResolveBalancesRegions(t *testing.T) {
type args struct {
addrs []*net.TCPAddr
}
tests := []struct {
name string
args args
}{
{
name: "one address",
args: args{addrs: []*net.TCPAddr{&addr0}},
},
{
name: "two addresses",
args: args{addrs: []*net.TCPAddr{&addr0, &addr1}},
},
}
for _, tt := range tests {
t.Run(tt.name, func(t *testing.T) {
regions := NewNoResolve(tt.args.addrs)
RegionsIsBalanced(t, regions)
})
}
}
func RegionsIsBalanced(t *testing.T, rs *Regions) {
delta := rs.region1.AvailableAddrs() - rs.region2.AvailableAddrs()
assert.True(t, abs(delta) <= 1)
}
func abs(x int) int {
if x >= 0 {
return x
}
return -x
}

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@ -0,0 +1,14 @@
package allregions
type UsedBy struct {
ConnID int
Used bool
}
func InUse(connID int) UsedBy {
return UsedBy{ConnID: connID, Used: true}
}
func Unused() UsedBy {
return UsedBy{}
}

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@ -0,0 +1,143 @@
package edgediscovery
import (
"fmt"
"net"
"sync"
"github.com/cloudflare/cloudflared/edgediscovery/allregions"
"github.com/sirupsen/logrus"
)
const (
subsystem = "edgediscovery"
)
var errNoAddressesLeft = fmt.Errorf("There are no free edge addresses left")
// Edge finds addresses on the Cloudflare edge and hands them out to connections.
type Edge struct {
regions *allregions.Regions
sync.Mutex
logger *logrus.Entry
}
// ------------------------------------
// Constructors
// ------------------------------------
// ResolveEdge runs the initial discovery of the Cloudflare edge, finding Addrs that can be allocated
// to connections.
func ResolveEdge(l *logrus.Logger) (*Edge, error) {
logger := l.WithField("subsystem", subsystem)
regions, err := allregions.ResolveEdge(logger)
if err != nil {
return new(Edge), err
}
return &Edge{
logger: logger,
regions: regions,
}, nil
}
// StaticEdge creates a list of edge addresses from the list of hostnames. Mainly used for testing connectivity.
func StaticEdge(l *logrus.Logger, hostnames []string) (*Edge, error) {
logger := l.WithField("subsystem", subsystem)
regions, err := allregions.StaticEdge(hostnames)
if err != nil {
return new(Edge), err
}
return &Edge{
logger: logger,
regions: regions,
}, nil
}
// MockEdge creates a Cloudflare Edge from arbitrary TCP addresses. Used for testing.
func MockEdge(l *logrus.Logger, addrs []*net.TCPAddr) *Edge {
logger := l.WithField("subsystem", subsystem)
regions := allregions.NewNoResolve(addrs)
return &Edge{
logger: logger,
regions: regions,
}
}
// ------------------------------------
// Methods
// ------------------------------------
// GetAddrForRPC gives this connection an edge Addr.
func (ed *Edge) GetAddrForRPC() (*net.TCPAddr, error) {
ed.Lock()
defer ed.Unlock()
addr := ed.regions.GetAnyAddress()
if addr == nil {
return nil, errNoAddressesLeft
}
return addr, nil
}
// GetAddr gives this proxy connection an edge Addr. Prefer Addrs this connection has already used.
func (ed *Edge) GetAddr(connID int) (*net.TCPAddr, error) {
ed.Lock()
defer ed.Unlock()
logger := ed.logger.WithFields(logrus.Fields{
"connID": connID,
"function": "GetAddr",
})
// If this connection has already used an edge addr, return it.
if addr := ed.regions.AddrUsedBy(connID); addr != nil {
logger.Debug("Returning same address back to proxy connection")
return addr, nil
}
// Otherwise, give it an unused one
addr := ed.regions.GetUnusedAddr(nil, connID)
if addr == nil {
logger.Debug("No addresses left to give proxy connection")
return nil, errNoAddressesLeft
}
logger.Debug("Giving connection its new address")
return addr, nil
}
// GetDifferentAddr gives back the proxy connection's edge Addr and uses a new one.
func (ed *Edge) GetDifferentAddr(connID int) (*net.TCPAddr, error) {
ed.Lock()
defer ed.Unlock()
logger := ed.logger.WithFields(logrus.Fields{
"connID": connID,
"function": "GetDifferentAddr",
})
oldAddr := ed.regions.AddrUsedBy(connID)
if oldAddr != nil {
ed.regions.GiveBack(oldAddr)
}
addr := ed.regions.GetUnusedAddr(oldAddr, connID)
if addr == nil {
logger.Debug("No addresses left to give proxy connection")
return nil, errNoAddressesLeft
}
logger.Debug("Giving connection its new address")
return addr, nil
}
// AvailableAddrs returns how many unused addresses there are left.
func (ed *Edge) AvailableAddrs() int {
ed.Lock()
defer ed.Unlock()
return ed.regions.AvailableAddrs()
}
// GiveBack the address so that other connections can use it.
// Returns true if the address is in this edge.
func (ed *Edge) GiveBack(addr *net.TCPAddr) bool {
ed.Lock()
defer ed.Unlock()
ed.logger.WithField("function", "GiveBack").Debug("Address now unused")
return ed.regions.GiveBack(addr)
}

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@ -0,0 +1,130 @@
package edgediscovery
import (
"net"
"testing"
"github.com/sirupsen/logrus"
"github.com/stretchr/testify/assert"
)
var (
addr0 = net.TCPAddr{
IP: net.ParseIP("123.0.0.0"),
Port: 8000,
Zone: "",
}
addr1 = net.TCPAddr{
IP: net.ParseIP("123.0.0.1"),
Port: 8000,
Zone: "",
}
addr2 = net.TCPAddr{
IP: net.ParseIP("123.0.0.2"),
Port: 8000,
Zone: "",
}
addr3 = net.TCPAddr{
IP: net.ParseIP("123.0.0.3"),
Port: 8000,
Zone: "",
}
)
func TestGiveBack(t *testing.T) {
l := logrus.New()
edge := MockEdge(l, []*net.TCPAddr{&addr0, &addr1, &addr2, &addr3})
// Give this connection an address
assert.Equal(t, 4, edge.AvailableAddrs())
const connID = 0
addr, err := edge.GetAddr(connID)
assert.NoError(t, err)
assert.NotNil(t, addr)
assert.Equal(t, 3, edge.AvailableAddrs())
// Get it back
edge.GiveBack(addr)
assert.Equal(t, 4, edge.AvailableAddrs())
}
func TestGetAddrForRPC(t *testing.T) {
l := logrus.New()
edge := MockEdge(l, []*net.TCPAddr{&addr0, &addr1, &addr2, &addr3})
// Get a connection
assert.Equal(t, 4, edge.AvailableAddrs())
addr, err := edge.GetAddrForRPC()
assert.NoError(t, err)
assert.NotNil(t, addr)
// Using an address for RPC shouldn't consume it
assert.Equal(t, 4, edge.AvailableAddrs())
// Get it back
edge.GiveBack(addr)
assert.Equal(t, 4, edge.AvailableAddrs())
}
func TestOnlyOneAddrLeft(t *testing.T) {
l := logrus.New()
// Make an edge with only one address
edge := MockEdge(l, []*net.TCPAddr{&addr0})
// Use the only address
const connID = 0
addr, err := edge.GetAddr(connID)
assert.NoError(t, err)
assert.NotNil(t, addr)
// If that edge address is "bad", there's no alternative address.
_, err = edge.GetDifferentAddr(connID)
assert.Error(t, err)
}
func TestNoAddrsLeft(t *testing.T) {
l := logrus.New()
// Make an edge with no addresses
edge := MockEdge(l, []*net.TCPAddr{})
_, err := edge.GetAddr(2)
assert.Error(t, err)
_, err = edge.GetAddrForRPC()
assert.Error(t, err)
}
func TestGetAddr(t *testing.T) {
l := logrus.New()
edge := MockEdge(l, []*net.TCPAddr{&addr0, &addr1, &addr2, &addr3})
// Give this connection an address
const connID = 0
addr, err := edge.GetAddr(connID)
assert.NoError(t, err)
assert.NotNil(t, addr)
// If the same connection requests another address, it should get the same one.
addr2, err := edge.GetAddr(connID)
assert.NoError(t, err)
assert.Equal(t, addr, addr2)
}
func TestGetDifferentAddr(t *testing.T) {
l := logrus.New()
edge := MockEdge(l, []*net.TCPAddr{&addr0, &addr1, &addr2, &addr3})
// Give this connection an address
assert.Equal(t, 4, edge.AvailableAddrs())
const connID = 0
addr, err := edge.GetAddr(connID)
assert.NoError(t, err)
assert.NotNil(t, addr)
assert.Equal(t, 3, edge.AvailableAddrs())
// If the same connection requests another address, it should get the same one.
addr2, err := edge.GetDifferentAddr(connID)
assert.NoError(t, err)
assert.NotEqual(t, addr, addr2)
assert.Equal(t, 3, edge.AvailableAddrs())
}

View File

@ -12,6 +12,7 @@ import (
"github.com/sirupsen/logrus"
"github.com/cloudflare/cloudflared/connection"
"github.com/cloudflare/cloudflared/edgediscovery"
"github.com/cloudflare/cloudflared/h2mux"
"github.com/cloudflare/cloudflared/signal"
tunnelpogs "github.com/cloudflare/cloudflared/tunnelrpc/pogs"
@ -39,10 +40,12 @@ var (
errEventDigestUnset = errors.New("event digest unset")
)
// Supervisor manages non-declarative tunnels. Establishes TCP connections with the edge, and
// reconnects them if they disconnect.
type Supervisor struct {
cloudflaredUUID uuid.UUID
config *TunnelConfig
edgeIPs connection.EdgeServiceDiscoverer
edgeIPs *edgediscovery.Edge
lastResolve time.Time
resolverC chan resolveResult
tunnelErrors chan tunnelError
@ -73,13 +76,13 @@ type tunnelError struct {
func NewSupervisor(config *TunnelConfig, u uuid.UUID) (*Supervisor, error) {
var (
edgeIPs connection.EdgeServiceDiscoverer
edgeIPs *edgediscovery.Edge
err error
)
if len(config.EdgeAddrs) > 0 {
edgeIPs, err = connection.NewEdgeHostnameResolver(config.EdgeAddrs)
edgeIPs, err = edgediscovery.StaticEdge(config.Logger, config.EdgeAddrs)
} else {
edgeIPs, err = connection.NewEdgeAddrResolver(config.Logger)
edgeIPs, err = edgediscovery.ResolveEdge(config.Logger)
}
if err != nil {
return nil, err
@ -141,14 +144,8 @@ func (s *Supervisor) Run(ctx context.Context, connectedSignal *signal.Signal) er
backoffTimer = backoff.BackoffTimer()
}
// If the error is a dial error, the problem is likely to be network related
// try another addr before refreshing since we are likely to get back the
// same IPs in the same order. Same problem with duplicate connection error.
if s.unusedIPs() && tunnelError.addr != nil {
s.edgeIPs.MarkAddrBad(tunnelError.addr)
} else {
s.refreshEdgeIPs()
}
// Previously we'd mark the edge address as bad here, but now we'll just silently use
// another.
}
// Backoff was set and its timer expired
case <-backoffTimer:
@ -191,11 +188,6 @@ func (s *Supervisor) Run(ctx context.Context, connectedSignal *signal.Signal) er
func (s *Supervisor) initialize(ctx context.Context, connectedSignal *signal.Signal) error {
logger := s.logger
err := s.edgeIPs.Refresh()
if err != nil {
logger.Infof("ResolveEdgeIPs err")
return err
}
s.lastResolve = time.Now()
availableAddrs := int(s.edgeIPs.AvailableAddrs())
if s.config.HAConnections > availableAddrs {
@ -228,17 +220,19 @@ func (s *Supervisor) startFirstTunnel(ctx context.Context, connectedSignal *sign
addr *net.TCPAddr
err error
)
const thisConnID = 0
defer func() {
s.tunnelErrors <- tunnelError{index: 0, addr: addr, err: err}
s.tunnelErrors <- tunnelError{index: thisConnID, addr: addr, err: err}
}()
addr, err = s.edgeIPs.Addr()
addr, err = s.edgeIPs.GetAddr(thisConnID)
if err != nil {
return
}
err = ServeTunnelLoop(ctx, s, s.config, addr, 0, connectedSignal, s.cloudflaredUUID)
err = ServeTunnelLoop(ctx, s, s.config, addr, thisConnID, connectedSignal, s.cloudflaredUUID)
// If the first tunnel disconnects, keep restarting it.
edgeErrors := 0
for s.unusedIPs() {
if ctx.Err() != nil {
return
@ -249,15 +243,17 @@ func (s *Supervisor) startFirstTunnel(ctx context.Context, connectedSignal *sign
// try the next address if it was a dialError(network problem) or
// dupConnRegisterTunnelError
case connection.DialError, dupConnRegisterTunnelError:
s.edgeIPs.MarkAddrBad(addr)
edgeErrors++
default:
return
}
addr, err = s.edgeIPs.Addr()
if edgeErrors >= 2 {
addr, err = s.edgeIPs.GetDifferentAddr(thisConnID)
if err != nil {
return
}
err = ServeTunnelLoop(ctx, s, s.config, addr, 0, connectedSignal, s.cloudflaredUUID)
}
err = ServeTunnelLoop(ctx, s, s.config, addr, thisConnID, connectedSignal, s.cloudflaredUUID)
}
}
@ -272,7 +268,7 @@ func (s *Supervisor) startTunnel(ctx context.Context, index int, connectedSignal
s.tunnelErrors <- tunnelError{index: index, addr: addr, err: err}
}()
addr, err = s.edgeIPs.Addr()
addr, err = s.edgeIPs.GetAddr(index)
if err != nil {
return
}
@ -302,20 +298,6 @@ func (s *Supervisor) unusedIPs() bool {
return s.edgeIPs.AvailableAddrs() > s.config.HAConnections
}
func (s *Supervisor) refreshEdgeIPs() {
if s.resolverC != nil {
return
}
if time.Since(s.lastResolve) < resolveTTL {
return
}
s.resolverC = make(chan resolveResult)
go func() {
err := s.edgeIPs.Refresh()
s.resolverC <- resolveResult{err: err}
}()
}
func (s *Supervisor) ReconnectToken() ([]byte, error) {
s.jwtLock.RLock()
defer s.jwtLock.RUnlock()
@ -385,7 +367,7 @@ func (s *Supervisor) refreshAuth(
}
func (s *Supervisor) authenticate(ctx context.Context, numPreviousAttempts int) (tunnelpogs.AuthOutcome, error) {
arbitraryEdgeIP, err := s.edgeIPs.AnyAddr()
arbitraryEdgeIP, err := s.edgeIPs.GetAddrForRPC()
if err != nil {
return nil, err
}

View File

@ -1,3 +1,4 @@
// Package supervisor is used by declarative tunnels to get/apply new config from the edge.
package supervisor
import (
@ -13,6 +14,7 @@ import (
"github.com/cloudflare/cloudflared/cmd/cloudflared/updater"
"github.com/cloudflare/cloudflared/connection"
"github.com/cloudflare/cloudflared/edgediscovery"
"github.com/cloudflare/cloudflared/h2mux"
"github.com/cloudflare/cloudflared/streamhandler"
"github.com/cloudflare/cloudflared/tunnelrpc/pogs"
@ -56,7 +58,7 @@ func NewSupervisor(
defaultClientConfig *pogs.ClientConfig,
userCredential []byte,
tlsConfig *tls.Config,
serviceDiscoverer connection.EdgeServiceDiscoverer,
serviceDiscoverer *edgediscovery.Edge,
cloudflaredConfig *connection.CloudflaredConfig,
autoupdater *updater.AutoUpdater,
supportAutoupdate bool,