init import

pkg/auxx509/x509cert.go

@@ -0,0 +1,66 @@
+/*
+ * Copyright 2026 Oleg Borodin <onborodin@gmail.com>
+ */
+package auxx509
+
+import (
+	"crypto/rand"
+	"crypto/rsa"
+	"crypto/x509"
+	"crypto/x509/pkix"
+	"encoding/pem"
+	"fmt"
+	"math/big"
+	"time"
+)
+
+func CreateSelfSignedCert(subject string, dnsNames ...string) ([]byte, []byte, error) {
+	var err error
+	certPem := make([]byte, 0)
+	keyPem := make([]byte, 0)
+
+	now := time.Now()
+
+	const yearsAfter int = 10
+	const keySize int = 2048
+
+	key, err := rsa.GenerateKey(rand.Reader, keySize)
+	if err != nil {
+		err := fmt.Errorf("Can't create a private key: %v", err)
+		return certPem, keyPem, err
+
+	}
+	keyPemBlock := pem.Block{
+		Type:  "RSA PRIVATE KEY",
+		Bytes: x509.MarshalPKCS1PrivateKey(key),
+	}
+	keyPem = pem.EncodeToMemory(&keyPemBlock)
+
+	names := make([]string, 0)
+	names = append(names, subject)
+	names = append(names, dnsNames...)
+	tml := x509.Certificate{
+		SerialNumber: big.NewInt(now.Unix()),
+		NotBefore:    now,
+		NotAfter:     now.AddDate(yearsAfter, 0, 0),
+		Subject: pkix.Name{
+			CommonName: subject,
+		},
+		DNSNames:              names,
+		BasicConstraintsValid: true,
+	}
+	certBytes, err := x509.CreateCertificate(rand.Reader, &tml, &tml, &key.PublicKey, key)
+	if err != nil {
+		return certPem, keyPem, fmt.Errorf("Can't create a certificate: %v", err)
+
+	}
+	certPemBlock := pem.Block{
+		Type:  "CERTIFICATE",
+		Bytes: certBytes,
+	}
+	certPem = pem.EncodeToMemory(&certPemBlock)
+	if err != nil {
+		return certPem, keyPem, err
+	}
+	return certPem, keyPem, err
+}

pkg/auxx509/x509cert_test.go

@@ -0,0 +1,18 @@
+/*
+ * Copyright 2026 Oleg Borodin <onborodin@gmail.com>
+ */
+package auxx509
+
+import (
+	"fmt"
+	"testing"
+
+	"github.com/stretchr/testify/require"
+)
+
+func TestCert(t *testing.T) {
+	caCert, caKey, err := CreateSelfSignedCert("test1")
+	require.NoError(t, err)
+	fmt.Println(string(caCert))
+	fmt.Println(string(caKey))
+}