feat: add tests

internal/cert/client_cert.go

@@ -0,0 +1,75 @@
+package cert
+
+import (
+	"bytes"
+	"crypto/rand"
+	"crypto/x509"
+	"crypto/x509/pkix"
+	"encoding/pem"
+	"fmt"
+	"time"
+
+	"gitlab.com/urkob/go-cert-gen/pkg/client"
+)
+
+type clientCert struct {
+	certPEM []byte
+	keyPEM  []byte
+}
+
+func (c *clientCert) Key() []byte {
+	return c.keyPEM
+}
+
+func (c *clientCert) PEM() []byte {
+	return c.certPEM
+}
+
+func newClientCert(config *client.ClientCertConfig, rootCA *x509.Certificate, rootKeyPEM []byte) ([]byte, []byte, error) {
+	template := &x509.Certificate{
+		SerialNumber: config.Serial,
+		Subject: pkix.Name{
+			Organization:  []string{config.Subject.Organization},
+			Country:       []string{config.Subject.Country},
+			Province:      []string{config.Subject.Province},
+			Locality:      []string{config.Subject.Locality},
+			StreetAddress: []string{config.Subject.StreetAddress},
+			PostalCode:    []string{config.Subject.PostalCode},
+		},
+		NotBefore:    time.Now(),
+		NotAfter:     time.Now().Add(config.Duration),
+		SubjectKeyId: config.SubjectKeyId,
+		ExtKeyUsage:  config.ExtKeyUsage,
+		KeyUsage:     config.KeyUsage,
+	}
+
+	block, _ := pem.Decode(rootKeyPEM)
+	caPrivKey, err := x509.ParsePKCS8PrivateKey(block.Bytes)
+	if err != nil {
+		return nil, nil, fmt.Errorf("x509.ParsePKCS8PrivateKey: %s", err)
+	}
+
+	priv, err := newPrivateKey()
+	if err != nil {
+		return nil, nil, fmt.Errorf("newPrivateKey: %s", err)
+	}
+
+	der, err := x509.CreateCertificate(rand.Reader, template, rootCA, &priv.PublicKey, caPrivKey)
+	if err != nil {
+		return nil, nil, fmt.Errorf("x509.CreateCertificate: %s", err)
+	}
+
+	out := &bytes.Buffer{}
+	err = pem.Encode(out, &pem.Block{Type: CERTIFICATE, Bytes: der})
+	if err != nil {
+		return nil, nil, fmt.Errorf("pem.Encode: %s", err)
+	}
+
+	certPEM := out.Bytes()
+	keyPEM, err := encodePrivateKey(priv)
+	if err != nil {
+		return nil, nil, fmt.Errorf("encodePrivateKey: %s", err)
+	}
+
+	return certPEM, keyPEM, nil
+}