}

	pemBytes, err := os.ReadFile(certFile)
	if err != nil {
		return nil, err
	}

	certpool := x509.NewCertPool()
	if !certpool.AppendCertsFromPEM(pemBytes) {
		return nil, fmt.Errorf("no certificates found in %s", certFile)
	}
	client.Transport.(*http.Transport).TLSClientConfig = &tls.Config{
		RootCAs: certpool,
	}

	return client, nil

func newCitadelClient(endpoint string, rootCert []byte) (pb.IstioCertificateServiceClient, error) {
	certPool := x509.NewCertPool()
	ok := certPool.AppendCertsFromPEM(rootCert)
	if !ok {
		return nil, fmt.Errorf("failed to append certificates")
	}
	config := tls.Config{
		RootCAs:            certPool,
		InsecureSkipVerify: true, // nolint: gosec // test only code
	}
	transportCreds := credentials.NewTLS(&config)

var certFiles = []string{
	"/sys/lib/tls/ca.pem",
}

func (c *Certificate) systemVerify(opts *VerifyOptions) (chains [][]*Certificate, err error) {
	return nil, nil
}

func loadSystemRoots() (*CertPool, error) {
	roots := NewCertPool()
	var bestErr error
	for _, file := range certFiles {
		data, err := os.ReadFile(file)
		if err == nil {
			roots.AppendCertsFromPEM(data)
			return roots, nil
		}

	data, err := macOS.SecCertificateCopyData(cert)
	if err != nil {
		return nil, err
	}
	return ParseCertificate(data)
}

func loadSystemRoots() (*CertPool, error) {
	return &CertPool{systemPool: true}, nil

# (Optional) Server IP address
ip_address = "127.0.0.1"

# Whether this certificate will be used for a TLS server
tls_www_server
```

Run `certtool.exe` and specify the configuration file to generate a certificate:

```
certtool.exe --generate-self-signed --load-privkey private.key --template cert.cnf --outfile public.crt
```

## 4. Install Certificates from Third-party CAs

	"errors"
	"strings"
	"syscall"
	"unsafe"
)

func loadSystemRoots() (*CertPool, error) {
	return &CertPool{systemPool: true}, nil
}

// Creates a new *syscall.CertContext representing the leaf certificate in an in-memory
// certificate store containing itself and all of the intermediate certificates specified
// in the opts.Intermediates CertPool.
//

	var address string
	if cc.URL != nil {
		address = *cc.URL
	}
	var certPool *x509.CertPool
	if len(cc.CABundle) > 0 {
		certPool = x509.NewCertPool()
		certPool.AppendCertsFromPEM(cc.CABundle)
	} else {
		var err error
		certPool, err = x509.SystemCertPool()
		if err != nil {
			return nil, err
		}
	}
	tlsClientConfig := &tls.Config{RootCAs: certPool, MinVersion: tls.VersionTLS12}
	client := http.Client{

	if err != nil {
		return nil, fmt.Errorf("failed to read key pair %s & %s, got %v", clientCert, clientKey, err)
	}
	certPool := x509.NewCertPool()
	if caCert != "" {
		certBytes, err := os.ReadFile(caCert)
		if err != nil {
			return nil, fmt.Errorf("failed to read cert file %s, got %v", caCert, err)
		}
		ok := certPool.AppendCertsFromPEM(certBytes)
		if !ok {
			return nil, fmt.Errorf("failed to append CA cert to the cert pool")
		}

	endpointUpdateChan chan struct{}
	remoteCaCertPool   *x509.CertPool
	meshConfig         mesh.Watcher
}

var (
	trustBundleLog = log.RegisterScope("trustBundle", "Workload mTLS trust bundle logs")
	remoteTimeout  = 10 * time.Second
)

// NewTrustBundle returns a new trustbundle
func NewTrustBundle(remoteCaCertPool *x509.CertPool, meshConfig mesh.Watcher) *TrustBundle {
	var err error
	tb := &TrustBundle{

	systemRootsPool()
	if systemRoots != nil {
		originalSystemRoots := *systemRoots
		defer func() { systemRoots = &originalSystemRoots }()
	}

	tests := []struct {
		name            string
		systemRoots     *CertPool
		systemPool      bool
		poolContent     []*Certificate
		forceFallback   bool
		returnsFallback bool
	}{
		{
			name:            "nil systemRoots",
			returnsFallback: true,
		},
		{