bump snap version

Tunnels exp backoff

.github/stale.yml

@@ -0,0 +1,17 @@
+# Number of days of inactivity before an issue becomes stale
+daysUntilStale: 60
+# Number of days of inactivity before a stale issue is closed
+daysUntilClose: 7
+# Issues with these labels will never be considered stale
+exemptLabels:
+  - pinned
+  - security
+# Label to use when marking an issue as stale
+staleLabel: wontfix
+# Comment to post when marking an issue as stale. Set to `false` to disable
+markComment: >
+  This issue has been automatically marked as stale because it has not had
+  recent activity. It will be closed if no further activity occurs. Thank you
+  for your contributions.
+# Comment to post when closing a stale issue. Set to `false` to disable
+closeComment: false

Dockerfile

@@ -1,4 +1,4 @@
-FROM golang AS build
+FROM golang:1.19 AS build
 
 ARG GIT_DESC=undefined
 

Makefile

@@ -10,7 +10,7 @@ NDK_CC_ARM64 = $(abspath ../../ndk-toolchain-arm64/bin/aarch64-linux-android21-c
 
 GO := go
 
-src = $(wildcard *.go)
+src = $(wildcard *.go */*.go */*/*.go) go.mod go.sum
 
 native: bin-native
 all: bin-linux-amd64 bin-linux-386 bin-linux-arm bin-linux-arm64 \

README.md

@@ -156,6 +156,8 @@ zagent248.hola.org,165.22.65.3,22222,22223,22224,22225,22226,digitalocean
 
 | Argument | Type | Description |
 | -------- | ---- | ----------- |
+| backoff-deadline | Duration | total duration of zgettunnels method attempts (default 5m0s) |
+| backoff-initial | Duration | initial average backoff delay for zgettunnels (randomized by +/-50%) (default 3s) |
 | bind-address | String | HTTP proxy address to listen to (default "127.0.0.1:8080") |
 | cafile | String | use custom CA certificate bundle file |
 | country | String | desired proxy location (default "us") |
@@ -168,7 +170,7 @@ zagent248.hola.org,165.22.65.3,22222,22223,22224,22225,22226,digitalocean
 | proxy-type | String | proxy type (Datacenter: direct) (Residential: lum) (default "direct") |
 | resolver | String | DNS/DoH/DoT resolver to workaround Hola blocked hosts. See https://github.com/ameshkov/dnslookup/ for upstream DNS URL format. (default "https://cloudflare-dns.com/dns-query") |
 | rotate | Duration | rotate user ID once per given period (default 1h0m0s) |
-| timeout | Duration | timeout for network operations (default 10s) |
+| timeout | Duration | timeout for network operations (default 35s) |
 | verbosity | Number | logging verbosity (10 - debug, 20 - info, 30 - warning, 40 - error, 50 - critical) (default 20) |
 
 ## See also

credservice.go

@@ -12,9 +12,10 @@ const DEFAULT_LIST_LIMIT = 3
 func CredService(interval, timeout time.Duration,
 	country string,
 	proxytype string,
-	logger *CondLogger) (auth AuthProvider,
-	tunnels *ZGetTunnelsResponse,
-	err error) {
+	logger *CondLogger,
+	backoffInitial time.Duration,
+	backoffDeadline time.Duration,
+) (auth AuthProvider, tunnels *ZGetTunnelsResponse, err error) {
 	var mux sync.Mutex
 	var auth_header, user_uuid string
 	auth = func() (res string) {
@@ -25,7 +26,8 @@ func CredService(interval, timeout time.Duration,
 	}
 
 	tx_res, tx_err := EnsureTransaction(context.Background(), timeout, func(ctx context.Context, client *http.Client) bool {
-		tunnels, user_uuid, err = Tunnels(ctx, client, country, proxytype, DEFAULT_LIST_LIMIT)
+		tunnels, user_uuid, err = Tunnels(ctx, logger, client, country, proxytype,
+			DEFAULT_LIST_LIMIT, timeout, backoffInitial, backoffDeadline)
 		if err != nil {
 			logger.Error("Configuration bootstrap error: %v. Retrying with the fallback mechanism...", err)
 			return false
@@ -55,7 +57,8 @@ func CredService(interval, timeout time.Duration,
 			<-ticker.C
 			logger.Info("Rotating credentials...")
 			tx_res, tx_err := EnsureTransaction(context.Background(), timeout, func(ctx context.Context, client *http.Client) bool {
-				tuns, user_uuid, err = Tunnels(ctx, client, country, proxytype, DEFAULT_LIST_LIMIT)
+				tuns, user_uuid, err = Tunnels(ctx, logger, client, country, proxytype,
+					DEFAULT_LIST_LIMIT, timeout, backoffInitial, backoffDeadline)
 				if err != nil {
 					logger.Error("Credential rotation error: %v. Retrying with the fallback mechanism...", err)
 					return false

csrand.go

@@ -10,6 +10,7 @@ type secureRandomSource struct{}
 var RandomSource secureRandomSource
 
 var int63Limit = big.NewInt(0).Lsh(big.NewInt(1), 63)
+var int64Limit = big.NewInt(0).Lsh(big.NewInt(1), 64)
 
 func (_ secureRandomSource) Seed(_ int64) {
 }
@@ -21,3 +22,11 @@ func (_ secureRandomSource) Int63() int64 {
 	}
 	return randNum.Int64()
 }
+
+func (_ secureRandomSource) Uint64() uint64 {
+	randNum, err := crand.Int(crand.Reader, int64Limit)
+	if err != nil {
+		panic(err)
+	}
+	return randNum.Uint64()
+}

go.mod

@@ -1,11 +1,39 @@
 module github.com/Snawoot/hola-proxy
 
-go 1.13
+go 1.19
 
 require (
-	github.com/AdguardTeam/dnsproxy v0.25.0
+	github.com/AdguardTeam/dnsproxy v0.46.6
 	github.com/campoy/unique v0.0.0-20180121183637-88950e537e7e
-	github.com/google/uuid v1.1.1
-	github.com/miekg/dns v1.1.29
-	golang.org/x/net v0.0.0-20200324143707-d3edc9973b7e
+	github.com/google/uuid v1.3.0
+	github.com/miekg/dns v1.1.50
+	golang.org/x/net v0.5.0
+)
+
+require (
+	github.com/AdguardTeam/golibs v0.11.4 // indirect
+	github.com/aead/chacha20 v0.0.0-20180709150244-8b13a72661da // indirect
+	github.com/aead/poly1305 v0.0.0-20180717145839-3fee0db0b635 // indirect
+	github.com/ameshkov/dnscrypt/v2 v2.2.5 // indirect
+	github.com/ameshkov/dnsstamps v1.0.3 // indirect
+	github.com/beefsack/go-rate v0.0.0-20220214233405-116f4ca011a0 // indirect
+	github.com/bluele/gcache v0.0.2 // indirect
+	github.com/cenkalti/backoff/v4 v4.2.0 // indirect
+	github.com/go-task/slim-sprig v0.0.0-20210107165309-348f09dbbbc0 // indirect
+	github.com/golang/mock v1.6.0 // indirect
+	github.com/google/pprof v0.0.0-20230131232505-5a9e8f65f08f // indirect
+	github.com/jessevdk/go-flags v1.5.0 // indirect
+	github.com/lucas-clemente/quic-go v0.31.1 // indirect
+	github.com/marten-seemann/qpack v0.3.0 // indirect
+	github.com/marten-seemann/qtls-go1-18 v0.1.4 // indirect
+	github.com/marten-seemann/qtls-go1-19 v0.1.2 // indirect
+	github.com/onsi/ginkgo/v2 v2.8.0 // indirect
+	github.com/patrickmn/go-cache v2.1.0+incompatible // indirect
+	golang.org/x/crypto v0.5.0 // indirect
+	golang.org/x/exp v0.0.0-20230203172020-98cc5a0785f9 // indirect
+	golang.org/x/mod v0.7.0 // indirect
+	golang.org/x/sys v0.4.0 // indirect
+	golang.org/x/text v0.6.0 // indirect
+	golang.org/x/tools v0.5.0 // indirect
+	gopkg.in/yaml.v3 v3.0.1 // indirect
 )

go.sum

@@ -1,72 +1,134 @@
-github.com/AdguardTeam/dnsproxy v0.25.0 h1:BTUPrrwB01GeQW5d2Xx4pH5HOFXcZxN1MTeNXXuy6vQ=
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+github.com/AdguardTeam/dnsproxy v0.46.5 h1:TiJZhwaIDDaKkqEfJ9AD9aroFjcHN8oEbKB8WfTjSIs=
+github.com/AdguardTeam/dnsproxy v0.46.5/go.mod h1:yKBVgFlE6CqTQtye++3e7SATaMPc4Ixij+KkHsM6HhM=
+github.com/AdguardTeam/dnsproxy v0.46.6 h1:a6Ex1ZIytHelbEyHJRGEKWNaJgY3OtArYkjoGLwErlI=
+github.com/AdguardTeam/dnsproxy v0.46.6/go.mod h1:ZEkTmTJ2XInT3aVy0mHtEnSWSclpHHj/9hfNXDuAk5k=
+github.com/AdguardTeam/golibs v0.11.2 h1:JbQB1Dg2JWStXgHh1QqBbOLWnP4t9oDjppoBH6TVXSE=
+github.com/AdguardTeam/golibs v0.11.2/go.mod h1:87bN2x4VsTritptE3XZg9l8T6gznWsIxHBcQ1DeRIXA=
+github.com/AdguardTeam/golibs v0.11.4 h1:IltyvxwCTN+xxJF5sh6VadF8Zfbf8elgCm9dgijSVzM=
+github.com/AdguardTeam/golibs v0.11.4/go.mod h1:87bN2x4VsTritptE3XZg9l8T6gznWsIxHBcQ1DeRIXA=
 github.com/aead/chacha20 v0.0.0-20180709150244-8b13a72661da h1:KjTM2ks9d14ZYCvmHS9iAKVt9AyzRSqNU1qabPih5BY=
 github.com/aead/chacha20 v0.0.0-20180709150244-8b13a72661da/go.mod h1:eHEWzANqSiWQsof+nXEI9bUVUyV6F53Fp89EuCh2EAA=
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 github.com/aead/poly1305 v0.0.0-20180717145839-3fee0db0b635/go.mod h1:lmLxL+FV291OopO93Bwf9fQLQeLyt33VJRUg5VJ30us=
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 github.com/patrickmn/go-cache v2.1.0+incompatible/go.mod h1:3Qf8kWWT7OJRJbdiICTKqZju1ZixQ/KpMGzzAfe6+WQ=
 github.com/pmezard/go-difflib v1.0.0 h1:4DBwDE0NGyQoBHbLQYPwSUPoCMWR5BEzIk/f1lZbAQM=
 github.com/pmezard/go-difflib v1.0.0/go.mod h1:iKH77koFhYxTK1pcRnkKkqfTogsbg7gZNVY4sRDYZ/4=
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 github.com/stretchr/objx v0.1.0/go.mod h1:HFkY916IF+rwdDfMAkV7OtwuqBVzrE8GR6GFx+wExME=
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 golang.org/x/crypto v0.0.0-20190308221718-c2843e01d9a2/go.mod h1:djNgcEr1/C05ACkg1iLfiJU5Ep61QUkGW8qpdssI0+w=
 golang.org/x/crypto v0.0.0-20191011191535-87dc89f01550/go.mod h1:yigFU9vqHzYiE8UmvKecakEJjdnWj3jj499lnFckfCI=
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 golang.org/x/net v0.0.0-20190404232315-eb5bcb51f2a3/go.mod h1:t9HGtf8HONx5eT2rtn7q6eTqICYqUVnKs3thJo3Qplg=
 golang.org/x/net v0.0.0-20190620200207-3b0461eec859/go.mod h1:z5CRVTTTmAJ677TzLLGU+0bjPO0LkuOLi4/5GtJWs/s=
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 golang.org/x/xerrors v0.0.0-20191011141410-1b5146add898/go.mod h1:I/5z698sn9Ka8TeJc9MKroUUfqBBauWjQqLJ2OPfmY0=
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+google.golang.org/protobuf v1.28.0 h1:w43yiav+6bVFTBQFZX0r7ipe9JQ1QsbMgHwbBziscLw=
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-gopkg.in/yaml.v2 v2.2.8 h1:obN1ZagJSUGI0Ek/LBmuj4SNLPfIny3KsKFopxRdj10=
-gopkg.in/yaml.v2 v2.2.8/go.mod h1:hI93XBmqTisBFMUTm0b8Fm+jr3Dg1NNxqwp+5A1VGuI=
+gopkg.in/yaml.v3 v3.0.1 h1:fxVm/GzAzEWqLHuvctI91KS9hhNmmWOoWu0XTYJS7CA=
+gopkg.in/yaml.v3 v3.0.1/go.mod h1:K4uyk7z7BCEPqu6E+C64Yfv1cQ7kz7rIZviUmN+EgEM=

holaapi.go

@@ -20,6 +20,7 @@ import (
 	"time"
 
 	"github.com/campoy/unique"
+	"github.com/cenkalti/backoff/v4"
 	"github.com/google/uuid"
 )
 
@@ -37,6 +38,7 @@ const AGENT_SUFFIX = ".hola.org"
 
 var TemporaryBanError = errors.New("temporary ban detected")
 var PermanentBanError = errors.New("permanent ban detected")
+var EmptyResponseError = errors.New("empty response")
 
 type CountryList []string
 
@@ -248,7 +250,13 @@ func zgettunnels(ctx context.Context,
 		reterr = err
 		return
 	}
-	reterr = json.Unmarshal(data, &tunnels)
+	err = json.Unmarshal(data, &tunnels)
+	if err != nil {
+		return nil, fmt.Errorf("unable to unmashal zgettunnels response: %w", err)
+	}
+	if len(tunnels.IPList) == 0 {
+		return nil, EmptyResponseError
+	}
 	res = &tunnels
 	return
 }
@@ -315,18 +323,46 @@ func GetFallbackProxies(ctx context.Context) (*FallbackConfig, error) {
 }
 
 func Tunnels(ctx context.Context,
+	logger *CondLogger,
 	client *http.Client,
 	country string,
 	proxy_type string,
-	limit uint) (res *ZGetTunnelsResponse, user_uuid string, reterr error) {
+	limit uint,
+	timeout time.Duration,
+	backoffInitial time.Duration,
+	backoffDeadline time.Duration,
+) (res *ZGetTunnelsResponse, user_uuid string, reterr error) {
 	u := uuid.New()
 	user_uuid = hex.EncodeToString(u[:])
-	initres, err := background_init(ctx, client, user_uuid)
+	ctx1, cancel := context.WithTimeout(ctx, timeout)
+	defer cancel()
+	initres, err := background_init(ctx1, client, user_uuid)
 	if err != nil {
 		reterr = err
 		return
 	}
-	res, reterr = zgettunnels(ctx, client, user_uuid, initres.Key, country, proxy_type, limit)
+	var bo backoff.BackOff = &backoff.ExponentialBackOff{
+		InitialInterval:     backoffInitial,
+		RandomizationFactor: 0.5,
+		Multiplier:          1.5,
+		MaxInterval:         10 * time.Minute,
+		MaxElapsedTime:      backoffDeadline,
+		Stop:                backoff.Stop,
+		Clock:               backoff.SystemClock,
+	}
+	bo = backoff.WithContext(bo, ctx)
+	err = backoff.RetryNotify(func() error {
+		ctx1, cancel := context.WithTimeout(ctx, timeout)
+		defer cancel()
+		res, reterr = zgettunnels(ctx1, client, user_uuid, initres.Key, country, proxy_type, limit)
+		return reterr
+	}, bo, func(err error, dur time.Duration) {
+		logger.Info("zgettunnels error: %v; will retry after %v", err, dur.Truncate(time.Millisecond))
+	})
+	if err != nil {
+		logger.Error("All attempts failed: %v", err)
+		return nil, "", err
+	}
 	return
 }
 
@@ -369,19 +405,18 @@ func httpClientWithProxy(agent *FallbackAgent) *http.Client {
 	}
 }
 
-func EnsureTransaction(baseCtx context.Context, txnTimeout time.Duration, txn func(context.Context, *http.Client) bool) (bool, error) {
+func EnsureTransaction(ctx context.Context, getFBTimeout time.Duration, txn func(context.Context, *http.Client) bool) (bool, error) {
 	client := httpClientWithProxy(nil)
 	defer client.CloseIdleConnections()
 
-	ctx, cancel := context.WithTimeout(baseCtx, txnTimeout)
-	defer cancel()
-
 	if txn(ctx, client) {
 		return true, nil
 	}
 
 	// Fallback needed
-	fbc, err := GetFallbackProxies(baseCtx)
+	getFBCtx, cancel := context.WithTimeout(ctx, getFBTimeout)
+	defer cancel()
+	fbc, err := GetFallbackProxies(getFBCtx)
 	if err != nil {
 		return false, err
 	}
@@ -389,10 +424,6 @@ func EnsureTransaction(baseCtx context.Context, txnTimeout time.Duration, txn fu
 	for _, agent := range fbc.Agents {
 		client = httpClientWithProxy(&agent)
 		defer client.CloseIdleConnections()
-
-		ctx, cancel = context.WithTimeout(baseCtx, txnTimeout)
-		defer cancel()
-
 		if txn(ctx, client) {
 			return true, nil
 		}

main.go

@@ -54,6 +54,10 @@ type CLIArgs struct {
 	showVersion                             bool
 	proxy                                   string
 	caFile                                  string
+	minPause                                time.Duration
+	maxPause                                time.Duration
+	backoffInitial                          time.Duration
+	backoffDeadline                         time.Duration
 }
 
 func parse_args() CLIArgs {
@@ -68,6 +72,8 @@ func parse_args() CLIArgs {
 		"(10 - debug, 20 - info, 30 - warning, 40 - error, 50 - critical)")
 	flag.DurationVar(&args.timeout, "timeout", 10*time.Second, "timeout for network operations")
 	flag.DurationVar(&args.rotate, "rotate", 1*time.Hour, "rotate user ID once per given period")
+	flag.DurationVar(&args.backoffInitial, "backoff-initial", 3*time.Second, "initial average backoff delay for zgettunnels (randomized by +/-50%)")
+	flag.DurationVar(&args.backoffDeadline, "backoff-deadline", 5*time.Minute, "total duration of zgettunnels method attempts")
 	flag.StringVar(&args.proxy_type, "proxy-type", "direct", "proxy type: direct or lum") // or skip but not mentioned
 	// skip would be used something like this: `./bin/hola-proxy -proxy-type skip -force-port-field 24232 -country ua.peer` for debugging
 	flag.StringVar(&args.resolver, "resolver", "https://cloudflare-dns.com/dns-query",
@@ -163,8 +169,10 @@ func run() int {
 	if args.list_countries {
 		return print_countries(args.timeout)
 	}
+
 	if args.list_proxies {
-		return print_proxies(args.country, args.proxy_type, args.limit, args.timeout)
+		return print_proxies(mainLogger, args.country, args.proxy_type, args.limit, args.timeout,
+			args.backoffInitial, args.backoffDeadline)
 	}
 
 	mainLogger.Info("hola-proxy client version %s is starting...", version)
@@ -176,7 +184,8 @@ func run() int {
 	}
 
 	mainLogger.Info("Initializing configuration provider...")
-	auth, tunnels, err := CredService(args.rotate, args.timeout, args.country, args.proxy_type, credLogger)
+	auth, tunnels, err := CredService(args.rotate, args.timeout, args.country, args.proxy_type, credLogger,
+		args.backoffInitial, args.backoffDeadline)
 	if err != nil {
 		mainLogger.Critical("Unable to instantiate credential service: %v", err)
 		return 4

resolver.go

@@ -1,9 +1,10 @@
 package main
 
 import (
+	"time"
+
 	"github.com/AdguardTeam/dnsproxy/upstream"
 	"github.com/miekg/dns"
-	"time"
 )
 
 type Resolver struct {
@@ -13,7 +14,7 @@ type Resolver struct {
 const DOT = 0x2e
 
 func NewResolver(address string, timeout time.Duration) (*Resolver, error) {
-	opts := upstream.Options{Timeout: timeout}
+	opts := &upstream.Options{Timeout: timeout}
 	u, err := upstream.AddressToUpstream(address, opts)
 	if err != nil {
 		return nil, err

snapcraft.yaml

@@ -1,5 +1,5 @@
 name: hola-proxy
-version: '1.5.4'
+version: '1.7.0'
 summary: Standalone Hola proxy client.
 description: |
   Standalone Hola proxy client. Just run it and it'll start plain HTTP proxy server forwarding traffic via Hola proxies of your choice.

utils.go

@@ -8,6 +8,7 @@ import (
 	"errors"
 	"fmt"
 	"io"
+	"math/rand"
 	"net"
 	"net/http"
 	"net/url"
@@ -111,7 +112,9 @@ func print_countries(timeout time.Duration) int {
 		err       error
 	)
 	tx_res, tx_err := EnsureTransaction(context.Background(), timeout, func(ctx context.Context, client *http.Client) bool {
-		countries, err = VPNCountries(ctx, client)
+		ctx1, cancel := context.WithTimeout(ctx, timeout)
+		defer cancel()
+		countries, err = VPNCountries(ctx1, client)
 		if err != nil {
 			fmt.Fprintf(os.Stderr, "Transaction error: %v. Retrying with the fallback mechanism...\n", err)
 			return false
@@ -132,14 +135,16 @@ func print_countries(timeout time.Duration) int {
 	return 0
 }
 
-func print_proxies(country string, proxy_type string, limit uint, timeout time.Duration) int {
+func print_proxies(logger *CondLogger, country string, proxy_type string,
+	limit uint, timeout time.Duration, backoffInitial time.Duration, backoffDeadline time.Duration,
+) int {
 	var (
 		tunnels   *ZGetTunnelsResponse
 		user_uuid string
 		err       error
 	)
 	tx_res, tx_err := EnsureTransaction(context.Background(), timeout, func(ctx context.Context, client *http.Client) bool {
-		tunnels, user_uuid, err = Tunnels(ctx, client, country, proxy_type, limit)
+		tunnels, user_uuid, err = Tunnels(ctx, logger, client, country, proxy_type, limit, timeout, backoffInitial, backoffDeadline)
 		if err != nil {
 			fmt.Fprintf(os.Stderr, "Transaction error: %v. Retrying with the fallback mechanism...\n", err)
 			return false
@@ -292,3 +297,11 @@ func copyBody(wr io.Writer, body io.Reader) {
 		}
 	}
 }
+
+func RandRange(low, hi int64) int64 {
+	if low >= hi {
+		panic("RandRange: low boundary is greater or equal to high boundary")
+	}
+	delta := hi - low
+	return low + rand.New(RandomSource).Int63n(delta+1)
+}