Maint: internal/openvpn/parse package

- Parse PEM key data for Cyberghost and VPNUnlimited
- Add more unit tests

internal/configuration/keys.go

@@ -1,11 +1,15 @@
 package configuration
 
 import (
-	"encoding/pem"
 	"errors"
-	"strings"
 
 	"github.com/qdm12/gluetun/internal/constants"
+	"github.com/qdm12/gluetun/internal/openvpn/parse"
+)
+
+var (
+	errClientCert = errors.New("cannot read client certificate")
+	errClientKey  = errors.New("cannot read client key")
 )
 
 func readClientKey(r reader) (clientKey string, err error) {
@@ -13,22 +17,7 @@ func readClientKey(r reader) (clientKey string, err error) {
 	if err != nil {
 		return "", err
 	}
-	return extractClientKey(b)
-}
-
-var errDecodePEMBlockClientKey = errors.New("cannot decode PEM block from client key")
-
-func extractClientKey(b []byte) (key string, err error) {
-	pemBlock, _ := pem.Decode(b)
-	if pemBlock == nil {
-		return "", errDecodePEMBlockClientKey
-	}
-	parsedBytes := pem.EncodeToMemory(pemBlock)
-	s := string(parsedBytes)
-	s = strings.ReplaceAll(s, "\n", "")
-	s = strings.TrimPrefix(s, "-----BEGIN PRIVATE KEY-----")
-	s = strings.TrimSuffix(s, "-----END PRIVATE KEY-----")
-	return s, nil
+	return parse.ExtractPrivateKey(b)
 }
 
 func readClientCertificate(r reader) (clientCertificate string, err error) {
@@ -36,20 +25,5 @@ func readClientCertificate(r reader) (clientCertificate string, err error) {
 	if err != nil {
 		return "", err
 	}
-	return extractClientCertificate(b)
-}
-
-var errDecodePEMBlockClientCert = errors.New("cannot decode PEM block from client certificate")
-
-func extractClientCertificate(b []byte) (certificate string, err error) {
-	pemBlock, _ := pem.Decode(b)
-	if pemBlock == nil {
-		return "", errDecodePEMBlockClientCert
-	}
-	parsedBytes := pem.EncodeToMemory(pemBlock)
-	s := string(parsedBytes)
-	s = strings.ReplaceAll(s, "\n", "")
-	s = strings.TrimPrefix(s, "-----BEGIN CERTIFICATE-----")
-	s = strings.TrimSuffix(s, "-----END CERTIFICATE-----")
-	return s, nil
+	return parse.ExtractCert(b)
 }