scan: replace uses of deprecated io/ioutil

Signed-off-by: Sebastiaan van Stijn <github@gone.nl>

Author: thaJeztah

scan/crypto/md5/gen.go

@@ -2,6 +2,7 @@
 // Use of this source code is governed by a BSD-style
 // license that can be found in the LICENSE file.
 
+//go:build ignore
 // +build ignore
 
 // This program generates md5block.go
@@ -18,7 +19,6 @@ import (
 	"bytes"
 	"flag"
 	"go/format"
-	"io/ioutil"
 	"log"
 	"strings"
 	"text/template"
@@ -40,7 +40,7 @@ func main() {
 	if err != nil {
 		log.Fatal(err)
 	}
-	err = ioutil.WriteFile(*filename, data, 0644)
+	err = os.WriteFile(*filename, data, 0644)
 	if err != nil {
 		log.Fatal(err)
 	}

scan/crypto/tls/handshake_test.go

@@ -11,8 +11,8 @@ import (
 	"flag"
 	"fmt"
 	"io"
-	"io/ioutil"
 	"net"
+	"os"
 	"strconv"
 	"strings"
 	"sync"
@@ -156,7 +156,7 @@ func parseTestData(r io.Reader) (flows [][]byte, err error) {
 
 // tempFile creates a temp file containing contents and returns its path.
 func tempFile(contents string) string {
-	file, err := ioutil.TempFile("", "go-tls-test")
+	file, err := os.CreateTemp("", "go-tls-test")
 	if err != nil {
 		panic("failed to create temp file: " + err.Error())
 	}

scan/crypto/tls/tls.go

@@ -18,8 +18,8 @@ import (
 	"encoding/pem"
 	"errors"
 	"fmt"
-	"io/ioutil"
 	"net"
+	"os"
 	"strings"
 	"time"
 )
@@ -176,11 +176,11 @@ func Dial(network, addr string, config *Config) (*Conn, error) {
 // Certificate.Leaf will be nil because the parsed form of the certificate is
 // not retained.
 func LoadX509KeyPair(certFile, keyFile string) (Certificate, error) {
-	certPEMBlock, err := ioutil.ReadFile(certFile)
+	certPEMBlock, err := os.ReadFile(certFile)
 	if err != nil {
 		return Certificate{}, err
 	}
-	keyPEMBlock, err := ioutil.ReadFile(keyFile)
+	keyPEMBlock, err := os.ReadFile(keyFile)
 	if err != nil {
 		return Certificate{}, err
 	}