Update to go 1.19

.github/workflows/ci.yaml

@@ -30,7 +30,7 @@ jobs:
     strategy:
       matrix:
         go_version:
-          - ^1.18
+          - ^1.19
     steps:
       - name: Checkout
         uses: actions/checkout@v2
@@ -70,7 +70,7 @@ jobs:
       - name: Run linter
         uses: golangci/golangci-lint-action@v2
         with:
-          version: v1.45.0
+          version: v1.48.0
 
   docker:
     name: Docker

.golangci.toml

@@ -9,4 +9,14 @@ format = "colored-line-number"
 
 [linters]
 enable-all = true
-disable = ["thelper", "ireturn", "varnamelen", "gochecknoglobals", "gas", "goerr113", "exhaustivestruct", "containedctx"]
+disable = [
+    "containedctx",
+    "exhaustivestruct",
+    "exhaustruct",
+    "gas",
+    "gochecknoglobals",
+    "goerr113",
+    "ireturn",
+    "thelper",
+    "varnamelen",
+]

Dockerfile

@@ -1,7 +1,7 @@
 ###############################################################################
 # BUILD STAGE
 
-FROM golang:1.18-alpine AS build
+FROM golang:1.19-alpine AS build
 
 RUN set -x \
   && apk --no-cache --update add \

Makefile

@@ -2,7 +2,7 @@ ROOT_DIR     := $(shell dirname $(realpath $(lastword $(MAKEFILE_LIST))))
 IMAGE_NAME   := mtg
 APP_NAME     := $(IMAGE_NAME)
 
-GOLANGCI_LINT_VERSION := v1.45.0
+GOLANGCI_LINT_VERSION := v1.48.0
 
 VERSION_GO         := $(shell go version)
 VERSION_DATE       := $(shell date -Ru)

config/global_ips.go

@@ -4,7 +4,6 @@ import (
 	"context"
 	"fmt"
 	"io"
-	"io/ioutil"
 	"net"
 	"net/http"
 	"strings"
@@ -46,7 +45,7 @@ func fetchIP(ctx context.Context, network string) (net.IP, error) {
 		},
 	}
 
-	req, err := http.NewRequest("GET", ifconfigAddress, nil)
+	req, err := http.NewRequest(http.MethodGet, ifconfigAddress, nil)
 	if err != nil {
 		return nil, fmt.Errorf("cannot create a request: %w", err)
 	}
@@ -54,7 +53,7 @@ func fetchIP(ctx context.Context, network string) (net.IP, error) {
 	resp, err := client.Do(req.WithContext(ctx))
 	if err != nil {
 		if resp != nil {
-			io.Copy(ioutil.Discard, resp.Body) // nolint: errcheck
+			io.Copy(io.Discard, resp.Body) //nolint: errcheck
 		}
 
 		return nil, fmt.Errorf("cannot perform a request: %w", err)
@@ -62,7 +61,7 @@ func fetchIP(ctx context.Context, network string) (net.IP, error) {
 
 	defer resp.Body.Close()
 
-	respDataBytes, err := ioutil.ReadAll(resp.Body)
+	respDataBytes, err := io.ReadAll(resp.Body)
 	if err != nil {
 		return nil, fmt.Errorf("cannot read response body: %w", err)
 	}

config/urls.go

@@ -20,8 +20,9 @@ type IPURLs struct {
 	BotSecret string `json:"secret_for_mtproxybot"` //nolint: tagliatelle
 }
 
-func GetURLs() (urls IPURLs) {
+func GetURLs() IPURLs {
 	secret := ""
+	urls := IPURLs{}
 
 	switch C.SecretMode {
 	case SecretModeSimple:

go.mod

@@ -14,8 +14,8 @@ require (
 	go.uber.org/multierr v1.8.0 // indirect
 	go.uber.org/zap v1.21.0
 	golang.org/x/crypto v0.0.0-20220315160706-3147a52a75dd
-	golang.org/x/net v0.0.0-20220225172249-27dd8689420f // indirect
+	golang.org/x/net v0.0.0-20220809012201-f428fae20770 // indirect
-	golang.org/x/sys v0.0.0-20220319134239-a9b59b0215f8
+	golang.org/x/sys v0.0.0-20220808155132-1c4a2a72c664
 	google.golang.org/protobuf v1.27.1 // indirect
 	gopkg.in/alecthomas/kingpin.v2 v2.2.6
 )
@@ -27,5 +27,8 @@ require (
 	github.com/golang/protobuf v1.5.2 // indirect
 	github.com/matttproud/golang_protobuf_extensions v1.0.1 // indirect
 	github.com/prometheus/client_model v0.2.0 // indirect
+	github.com/yuin/goldmark v1.4.13 // indirect
 	go.uber.org/atomic v1.9.0 // indirect
+	golang.org/x/mod v0.6.0-dev.0.20220419223038-86c51ed26bb4 // indirect
+	golang.org/x/tools v0.1.12 // indirect
 )

go.sum

@@ -208,6 +208,8 @@ github.com/yuin/goldmark v1.1.25/go.mod h1:3hX8gzYuyVAZsxl0MRgGTJEmQBFcNTphYh9de
 github.com/yuin/goldmark v1.1.27/go.mod h1:3hX8gzYuyVAZsxl0MRgGTJEmQBFcNTphYh9decYSb74=
 github.com/yuin/goldmark v1.1.32/go.mod h1:3hX8gzYuyVAZsxl0MRgGTJEmQBFcNTphYh9decYSb74=
 github.com/yuin/goldmark v1.3.5/go.mod h1:mwnBkeHKe2W/ZEtQ+71ViKU8L12m81fl3OWwC1Zlc8k=
+github.com/yuin/goldmark v1.4.13 h1:fVcFKWvrslecOb/tg+Cc05dkeYx540o0FuFt3nUVDoE=
+github.com/yuin/goldmark v1.4.13/go.mod h1:6yULJ656Px+3vBD8DxQVa3kxgyrAnzto9xy5taEt/CY=
 go.opencensus.io v0.21.0/go.mod h1:mSImk1erAIZhrmZN+AvHh14ztQfjbGwt4TtuofqLduU=
 go.opencensus.io v0.22.0/go.mod h1:+kGneAE2xo2IficOXnaByMWTGM9T73dGwxeWcUqIpI8=
 go.opencensus.io v0.22.2/go.mod h1:yxeiOL68Rb0Xd1ddK5vPZ/oVn4vY4Ynel7k9FzqtOIw=
@@ -262,6 +264,8 @@ golang.org/x/mod v0.1.1-0.20191107180719-034126e5016b/go.mod h1:QqPTAvyqsEbceGzB
 golang.org/x/mod v0.2.0/go.mod h1:s0Qsj1ACt9ePp/hMypM3fl4fZqREWJwdYDEqhRiZZUA=
 golang.org/x/mod v0.3.0/go.mod h1:s0Qsj1ACt9ePp/hMypM3fl4fZqREWJwdYDEqhRiZZUA=
 golang.org/x/mod v0.4.2/go.mod h1:s0Qsj1ACt9ePp/hMypM3fl4fZqREWJwdYDEqhRiZZUA=
+golang.org/x/mod v0.6.0-dev.0.20220419223038-86c51ed26bb4 h1:6zppjxzCulZykYSLyVDYbneBfbaBIQPYMevg0bEwv2s=
+golang.org/x/mod v0.6.0-dev.0.20220419223038-86c51ed26bb4/go.mod h1:jJ57K6gSWd91VN4djpZkiMVwK6gcyfeH4XE8wZrZaV4=
 golang.org/x/net v0.0.0-20180724234803-3673e40ba225/go.mod h1:mL1N/T3taQHkDXs73rZJwtUhF3w3ftmwwsq0BUmARs4=
 golang.org/x/net v0.0.0-20180826012351-8a410e7b638d/go.mod h1:mL1N/T3taQHkDXs73rZJwtUhF3w3ftmwwsq0BUmARs4=
 golang.org/x/net v0.0.0-20181114220301-adae6a3d119a/go.mod h1:mL1N/T3taQHkDXs73rZJwtUhF3w3ftmwwsq0BUmARs4=
@@ -294,6 +298,8 @@ golang.org/x/net v0.0.0-20210405180319-a5a99cb37ef4/go.mod h1:p54w0d4576C0XHj96b
 golang.org/x/net v0.0.0-20210525063256-abc453219eb5/go.mod h1:9nx3DQGgdP8bBQD5qxJ1jj9UTztislL4KSBs9R2vV5Y=
 golang.org/x/net v0.0.0-20220225172249-27dd8689420f h1:oA4XRj0qtSt8Yo1Zms0CUlsT3KG69V2UGQWPBxujDmc=
 golang.org/x/net v0.0.0-20220225172249-27dd8689420f/go.mod h1:CfG3xpIq0wQ8r1q4Su4UZFWDARRcnwPjda9FqA0JpMk=
+golang.org/x/net v0.0.0-20220809012201-f428fae20770 h1:dIi4qVdvjZEjiMDv7vhokAZNGnz3kepwuXqFKYDdDMs=
+golang.org/x/net v0.0.0-20220809012201-f428fae20770/go.mod h1:YDH+HFinaLZZlnHAfSS6ZXJJ9M9t4Dl22yv3iI2vPwk=
 golang.org/x/oauth2 v0.0.0-20180821212333-d2e6202438be/go.mod h1:N/0e6XlmueqKjAGxoOufVs8QHGRruUQn6yWY3a++T0U=
 golang.org/x/oauth2 v0.0.0-20190226205417-e64efc72b421/go.mod h1:gOpvHmFTYa4IltrdGE7lF6nIHvwfUNPOp7c8zoXwtLw=
 golang.org/x/oauth2 v0.0.0-20190604053449-0f29369cfe45/go.mod h1:gOpvHmFTYa4IltrdGE7lF6nIHvwfUNPOp7c8zoXwtLw=
@@ -351,6 +357,8 @@ golang.org/x/sys v0.0.0-20220114195835-da31bd327af9/go.mod h1:oPkhp1MJrh7nUepCBc
 golang.org/x/sys v0.0.0-20220204135822-1c1b9b1eba6a/go.mod h1:oPkhp1MJrh7nUepCBck5+mAzfO9JrbApNNgaTdGDITg=
 golang.org/x/sys v0.0.0-20220319134239-a9b59b0215f8 h1:OH54vjqzRWmbJ62fjuhxy7AxFFgoHN0/DPc/UrL8cAs=
 golang.org/x/sys v0.0.0-20220319134239-a9b59b0215f8/go.mod h1:oPkhp1MJrh7nUepCBck5+mAzfO9JrbApNNgaTdGDITg=
+golang.org/x/sys v0.0.0-20220808155132-1c4a2a72c664 h1:v1W7bwXHsnLLloWYTVEdvGvA7BHMeBYsPcF0GLDxIRs=
+golang.org/x/sys v0.0.0-20220808155132-1c4a2a72c664/go.mod h1:oPkhp1MJrh7nUepCBck5+mAzfO9JrbApNNgaTdGDITg=
 golang.org/x/term v0.0.0-20201126162022-7de9c90e9dd1/go.mod h1:bj7SfCRtBDWHUb9snDiAeCFNEtKQo2Wmx5Cou7ajbmo=
 golang.org/x/text v0.0.0-20170915032832-14c0d48ead0c/go.mod h1:NqM8EUOU14njkJ3fqMW+pc6Ldnwhi/IjpwHt7yyuwOQ=
 golang.org/x/text v0.3.0/go.mod h1:NqM8EUOU14njkJ3fqMW+pc6Ldnwhi/IjpwHt7yyuwOQ=
@@ -402,6 +410,8 @@ golang.org/x/tools v0.0.0-20200729194436-6467de6f59a7/go.mod h1:njjCfa9FT2d7l9Bc
 golang.org/x/tools v0.0.0-20200804011535-6c149bb5ef0d/go.mod h1:njjCfa9FT2d7l9Bc6FUM5FLjQPp3cFF28FI3qnDFljA=
 golang.org/x/tools v0.0.0-20200825202427-b303f430e36d/go.mod h1:njjCfa9FT2d7l9Bc6FUM5FLjQPp3cFF28FI3qnDFljA=
 golang.org/x/tools v0.1.5/go.mod h1:o0xws9oXOQQZyjljx8fwUC0k7L1pTE6eaCbjGeHmOkk=
+golang.org/x/tools v0.1.12 h1:VveCTK38A2rkS8ZqFY25HIDFscX5X9OoEhJd3quQmXU=
+golang.org/x/tools v0.1.12/go.mod h1:hNGJHUnrk76NpqgfD5Aqm5Crs+Hm0VOH/i9J2+nxYbc=
 golang.org/x/xerrors v0.0.0-20190717185122-a985d3407aa7/go.mod h1:I/5z698sn9Ka8TeJc9MKroUUfqBBauWjQqLJ2OPfmY0=
 golang.org/x/xerrors v0.0.0-20191011141410-1b5146add898/go.mod h1:I/5z698sn9Ka8TeJc9MKroUUfqBBauWjQqLJ2OPfmY0=
 golang.org/x/xerrors v0.0.0-20191204190536-9bdfabe68543/go.mod h1:I/5z698sn9Ka8TeJc9MKroUUfqBBauWjQqLJ2OPfmY0=

main.go

@@ -9,7 +9,6 @@ import (
 
 	"github.com/9seconds/mtg/cli"
 	"github.com/9seconds/mtg/config"
-	"github.com/9seconds/mtg/utils"
 	kingpin "gopkg.in/alecthomas/kingpin.v2"
 )
 
@@ -128,10 +127,6 @@ func main() {
 	app.Version(getVersion())
 	app.HelpFlag.Short('h')
 
-	if err := utils.SetLimits(); err != nil {
-		cli.Fatal(err)
-	}
-
 	switch kingpin.MustParse(app.Parse(os.Args[1:])) {
 	case generateSecretCommand.FullCommand():
 		cli.Generate(*generateSecretType, *generateCloakHost)

obfuscated2/client_protocol.go

@@ -93,12 +93,14 @@ func (c *ClientProtocol) Handshake(socket conntypes.StreamReadWriteCloser) (conn
 	return stream.NewObfuscated2(socket, encryptor, decryptor), nil
 }
 
-func (c *ClientProtocol) ReadFrame(socket conntypes.StreamReader) (fm Frame, err error) {
+func (c *ClientProtocol) ReadFrame(socket conntypes.StreamReader) (Frame, error) {
-	if _, err = io.ReadFull(handshakeReader{socket}, fm.Bytes()); err != nil {
+	fm := Frame{}
-		err = fmt.Errorf("cannot extract obfuscated2 frame: %w", err)
+
+	if _, err := io.ReadFull(handshakeReader{socket}, fm.Bytes()); err != nil {
+		return fm, fmt.Errorf("cannot extract obfuscated2 frame: %w", err)
 	}
 
-	return
+	return fm, nil
 }
 
 type handshakeReader struct {

obfuscated2/frame.go

@@ -44,11 +44,11 @@ func (f *Frame) Unique() []byte {
 	return f.data[frameOffsetFirst:frameOffsetDC]
 }
 
-func (f *Frame) Invert() (nf Frame) {
+func (f *Frame) Invert() Frame {
-	nf = *f
+	nf := *f
 	for i := 0; i < frameLenKey+frameLenIV; i++ {
 		nf.data[frameOffsetFirst+i] = f.data[frameOffsetIV-1-i]
 	}
 
-	return
+	return nf
 }

obfuscated2/telegram_protocol.go

@@ -39,7 +39,8 @@ func TelegramProtocol(req *protocol.TelegramRequest) (conntypes.StreamReadWriteC
 	return stream.NewObfuscated2(conn, encryptor, decryptor), nil
 }
 
-func generateFrame(cp protocol.ClientProtocol) (fm Frame) {
+func generateFrame(cp protocol.ClientProtocol) Frame {
+	fm := Frame{}
 	data := fm.Bytes()
 
 	for {
@@ -63,6 +64,6 @@ func generateFrame(cp protocol.ClientProtocol) (fm Frame) {
 
 		copy(fm.Magic(), cp.ConnectionType().Tag())
 
-		return
+		return fm
 	}
 }

stats/stats.go

@@ -32,7 +32,7 @@ func Init(ctx context.Context) error {
 
 	go func() {
 		<-ctx.Done()
-		srv.Shutdown(context.Background()) // nolint: errcheck, contextcheck
+		srv.Shutdown(context.Background()) //nolint: errcheck
 	}()
 
 	Stats = multiStats(stats)

telegram/api/api.go

@@ -4,7 +4,6 @@ import (
 	"context"
 	"fmt"
 	"io"
-	"io/ioutil"
 	"net/http"
 	"time"
 )
@@ -22,7 +21,7 @@ func request(url string) (io.ReadCloser, error) {
 	ctx, cancel := context.WithTimeout(context.Background(), apiHTTPTimeout)
 	defer cancel()
 
-	req, err := http.NewRequestWithContext(ctx, "GET", url, nil)
+	req, err := http.NewRequestWithContext(ctx, http.MethodGet, url, nil)
 	if err != nil {
 		panic(err)
 	}
@@ -33,7 +32,7 @@ func request(url string) (io.ReadCloser, error) {
 	resp, err := httpClient.Do(req)
 	if err != nil {
 		if resp != nil {
-			io.Copy(ioutil.Discard, resp.Body) // nolint: errcheck
+			io.Copy(io.Discard, resp.Body) //nolint: errcheck
 			resp.Body.Close()
 		}
 

telegram/api/secret.go

@@ -2,7 +2,7 @@ package api
 
 import (
 	"fmt"
-	"io/ioutil"
+	"io"
 )
 
 const secretURL = "https://core.telegram.org/getProxySecret" //nolint: gas
@@ -15,7 +15,7 @@ func Secret() ([]byte, error) {
 
 	defer resp.Close()
 
-	secret, err := ioutil.ReadAll(resp)
+	secret, err := io.ReadAll(resp)
 	if err != nil {
 		return nil, fmt.Errorf("cannot read response: %w", err)
 	}

tlstypes/consts.go

@@ -20,22 +20,22 @@ const (
 type CipherSuiteType uint8
 
 const (
-	CipherSuiteType_TLS_AES_128_GCM_SHA256       CipherSuiteType = iota // nolint: stylecheck,golint,revive
+	CipherSuiteType_TLS_AES_128_GCM_SHA256       CipherSuiteType = iota //nolint: stylecheck,golint,revive,nosnakecase
-	CipherSuiteType_TLS_AES_256_GCM_SHA384                              // nolint: stylecheck,golint,revive
+	CipherSuiteType_TLS_AES_256_GCM_SHA384                              //nolint: stylecheck,golint,revive,nosnakecase
-	CipherSuiteType_TLS_CHACHA20_POLY1305_SHA256                        // nolint: stylecheck,golint,revive
+	CipherSuiteType_TLS_CHACHA20_POLY1305_SHA256                        //nolint: stylecheck,golint,revive,nosnakecase
 )
 
 func (c CipherSuiteType) Bytes() []byte {
 	switch c {
-	case CipherSuiteType_TLS_AES_128_GCM_SHA256:
+	case CipherSuiteType_TLS_AES_128_GCM_SHA256: //nolint: nosnakecase
-		return CipherSuiteType_TLS_AES_128_GCM_SHA256_Bytes
+		return CipherSuiteType_TLS_AES_128_GCM_SHA256_Bytes //nolint: nosnakecase
-	case CipherSuiteType_TLS_AES_256_GCM_SHA384:
+	case CipherSuiteType_TLS_AES_256_GCM_SHA384: //nolint: nosnakecase
-		return CipherSuiteType_TLS_AES_256_GCM_SHA384_Bytes
+		return CipherSuiteType_TLS_AES_256_GCM_SHA384_Bytes //nolint: nosnakecase
-	case CipherSuiteType_TLS_CHACHA20_POLY1305_SHA256:
+	case CipherSuiteType_TLS_CHACHA20_POLY1305_SHA256: //nolint: nosnakecase
-		return CipherSuiteType_TLS_CHACHA20_POLY1305_SHA256_Bytes
+		return CipherSuiteType_TLS_CHACHA20_POLY1305_SHA256_Bytes //nolint: nosnakecase
 	}
 
-	return CipherSuiteType_TLS_CHACHA20_POLY1305_SHA256_Bytes
+	return CipherSuiteType_TLS_CHACHA20_POLY1305_SHA256_Bytes //nolint: nosnakecase
 }
 
 type Version uint8
@@ -69,9 +69,9 @@ var (
 	Version12Bytes = []byte{0x03, 0x03}
 	Version13Bytes = []byte{0x03, 0x04}
 
-	CipherSuiteType_TLS_AES_128_GCM_SHA256_Bytes       = []byte{0x13, 0x01} // nolint: stylecheck,golint,revive
+	CipherSuiteType_TLS_AES_128_GCM_SHA256_Bytes       = []byte{0x13, 0x01} //nolint: stylecheck,golint,revive,nosnakecase
-	CipherSuiteType_TLS_AES_256_GCM_SHA384_Bytes       = []byte{0x13, 0x02} // nolint: stylecheck,golint,revive
+	CipherSuiteType_TLS_AES_256_GCM_SHA384_Bytes       = []byte{0x13, 0x02} //nolint: stylecheck,golint,revive,nosnakecase
-	CipherSuiteType_TLS_CHACHA20_POLY1305_SHA256_Bytes = []byte{0x13, 0x03} // nolint: stylecheck,golint,revive
+	CipherSuiteType_TLS_CHACHA20_POLY1305_SHA256_Bytes = []byte{0x13, 0x03} //nolint: stylecheck,golint,revive,nosnakecase
 )
 
 type Byter interface {

tlstypes/record.go

@@ -65,7 +65,9 @@ func ReadRecord(reader io.Reader) (Record, error) {
 	return rec, nil
 }
 
-func MakeRecords(raw []byte) (arr []Record) {
+func MakeRecords(raw []byte) []Record {
+	var arr []Record
+
 	for len(raw) > 0 {
 		chunkSize := recordMaxChunkSize
 		if chunkSize > len(raw) {
@@ -80,5 +82,5 @@ func MakeRecords(raw []byte) (arr []Record) {
 		raw = raw[chunkSize:]
 	}
 
-	return
+	return arr
 }

tlstypes/server_hello.go

@@ -66,7 +66,7 @@ func NewServerHello(clientHello *ClientHello) *ServerHello {
 	rv.SessionID = make([]byte, len(clientHello.SessionID))
 	copy(rv.SessionID, clientHello.SessionID)
 
-	tail := bytes.NewBuffer(CipherSuiteType_TLS_AES_128_GCM_SHA256_Bytes)
+	tail := bytes.NewBuffer(CipherSuiteType_TLS_AES_128_GCM_SHA256_Bytes) //nolint: nosnakecase
 	tail.WriteByte(0x00)                                                  //nolint: gomnd // no compression
 	makeTLSExtensions(tail)
 	rv.Tail = RawBytes(tail.Bytes())

utils/read_full.go

@@ -4,12 +4,13 @@ import "io"
 
 const readFullBufferSize = 1024 + 1 // +1 because telegram opreates with blocks mod 4
 
-func ReadFull(src io.Reader) (rv []byte, err error) {
+func ReadFull(src io.Reader) ([]byte, error) {
 	buf := make([]byte, readFullBufferSize)
 	n := readFullBufferSize
+	rv := []byte{}
 
 	for n == len(buf) {
-		n, err = src.Read(buf)
+		n, err := src.Read(buf)
 		if err != nil {
 			return nil, err //nolint: wrapcheck
 		}

utils/rlimit.go

@@ -1,25 +0,0 @@
-//go:build !windows
-// +build !windows
-
-package utils
-
-import (
-	"fmt"
-
-	"golang.org/x/sys/unix"
-)
-
-func SetLimits() error {
-	rLimit := unix.Rlimit{}
-	if err := unix.Getrlimit(unix.RLIMIT_NOFILE, &rLimit); err != nil {
-		return fmt.Errorf("cannot get rlimit: %w", err)
-	}
-
-	rLimit.Cur = rLimit.Max
-
-	if err := unix.Setrlimit(unix.RLIMIT_NOFILE, &rLimit); err != nil {
-		return fmt.Errorf("cannot set rlimit: %w", err)
-	}
-
-	return nil
-}

wrappers/packet/mtproto_frame.go

@@ -7,7 +7,6 @@ import (
 	"fmt"
 	"hash/crc32"
 	"io"
-	"io/ioutil"
 	"net"
 
 	"github.com/9seconds/mtg/conntypes"
@@ -28,10 +27,13 @@ var mtprotoFramePadding = []byte{0x04, 0x00, 0x00, 0x00}
 //
 // MSGLEN is the length of the message + len of seqno and msglen.
 // SEQNO is the number of frame in the receive/send sequence. If client
+//
 //	sends a message with SeqNo 18, it has to receive message with SeqNo 18.
+//
 // MSG is the data which has to be written
 // CRC32 is the CRC32 checksum of MSGLEN + SEQNO + MSG
 // PADDING is custom padding schema to complete frame length to such that
+//
 //	len(frame) % 16 == 0
 type wrapperMtprotoFrame struct {
 	parent     conntypes.StreamReadWriteCloser
@@ -84,7 +86,7 @@ func (w *wrapperMtprotoFrame) Read() (conntypes.Packet, error) { // nolint: funl
 		return nil, fmt.Errorf("unexpected sequence number %d (wait for %d)", seqNo, w.readSeqNo)
 	}
 
-	data, _ := ioutil.ReadAll(buf)
+	data, _ := io.ReadAll(buf)
 	buf.Reset()
 	// write to buf, not to writer. This is because we are going to fetch
 	// crc32 checksum.