chore: get rid of deprecated ioutil package

Fixes #3

buildcert.go

@@ -4,7 +4,6 @@ import (
 	"context"
 	"encoding/pem"
 	"fmt"
-	"io/ioutil"
 	"os"
 	"os/exec"
 	"os/user"
@@ -128,7 +127,7 @@ func (b *tCertificateBuilder) MustWrite(force bool) bool {
 	if force || sys_stat.Size != int64(len(b.text)) {
 		return true
 	}
-	existing, err := ioutil.ReadFile(b.Config.Path)
+	existing, err := os.ReadFile(b.Config.Path)
 	if err != nil {
 		return true
 	}
@@ -143,7 +142,7 @@ func (b *tCertificateBuilder) MustWrite(force bool) bool {
 // Write the file's data
 func (b *tCertificateBuilder) WriteFile() error {
 	log.WithField("file", b.Config.Path).Info("Writing certificate data to file")
-	err := ioutil.WriteFile(b.Config.Path, b.text, b.Config.FileMode())
+	err := os.WriteFile(b.Config.Path, b.text, b.Config.FileMode())
 	if err == nil {
 		b.changed = true
 	}
@@ -262,7 +261,7 @@ func (b *tCertificateBuilder) appendPemFiles(files []string) error {
 
 // Append a PEM file to the current list of data chunks
 func (b *tCertificateBuilder) appendPem(input string) error {
-	data, err := ioutil.ReadFile(input)
+	data, err := os.ReadFile(input)
 	if err != nil {
 		return fmt.Errorf("Could not load '%s': %w", input, err)
 	}

config.go

@@ -3,7 +3,6 @@ package main
 import (
 	"crypto/x509"
 	"fmt"
-	"io/ioutil"
 	"os"
 	"os/user"
 	"strconv"
@@ -153,7 +152,7 @@ func (c *tLdapConnectionConfig) Validate() error {
 		return fmt.Errorf("Invalid TLS mode '%s' (valid values are 'yes', 'starttls' and 'no'", c.TLS)
 	}
 	if c.CaChain != "" {
-		data, err := ioutil.ReadFile(c.CaChain)
+		data, err := os.ReadFile(c.CaChain)
 		if err != nil {
 			return fmt.Errorf("Unable to read CA chain from '%s': %w", c.CaChain, err)
 		}
@@ -351,7 +350,7 @@ func defaultConfiguration() tConfiguration {
 // Load and check the configuration file
 func LoadConfiguration(file string) (tConfiguration, error) {
 	cfg := defaultConfiguration()
-	cfgData, err := ioutil.ReadFile(file)
+	cfgData, err := os.ReadFile(file)
 	if err != nil {
 		return cfg, fmt.Errorf("Could not load configuration: %w", err)
 	}

ldap.go

@@ -5,7 +5,7 @@ import (
 	"crypto/x509"
 	"encoding/pem"
 	"fmt"
-	"io/ioutil"
+	"os"
 
 	ldap "github.com/go-ldap/ldap/v3"
 	"github.com/sirupsen/logrus"
@@ -68,7 +68,7 @@ func getLdapServerConnection(cfg tLdapConfig, server int) *tLdapConn {
 	}
 	if scfg.TLS != "no" && scfg.CaChain != "" {
 		log := log.WithField("cachain", scfg.CaChain)
-		data, err := ioutil.ReadFile(scfg.CaChain)
+		data, err := os.ReadFile(scfg.CaChain)
 		if err != nil {
 			log.WithField("error", err).Error("Failed to read CA certificate chain")
 			return nil

logging.go

@@ -1,7 +1,7 @@
 package main
 
 import (
-	"io/ioutil"
+	"io"
 	"log/syslog"
 	"os"
 
@@ -67,7 +67,7 @@ func configureLogging(flags tCliFlags) error {
 		log.Logger.AddHook(hook)
 	}
 	if flags.quiet {
-		log.Logger.SetOutput(ioutil.Discard)
+		log.Logger.SetOutput(io.Discard)
 	}
 	return nil
 }