golang openssl example

openssl_conn.go

// NewOpenSSLTransport returns a TCP connection establish with OpenSSL.
func NewOpenSSLTransport(trustPath, certPath, keyPath, host, port string, dialOpts *OpenSSLDialOptions) (*openssl.Conn, error) {

	// Default to flag 0
	if dialOpts == nil {
		dialOpts = &OpenSSLDialOptions{}
	}

	ctx, err := openssl.NewCtx()
	if err != nil {
		return nil, err
	}
	ctx.SetOptions(openssl.CipherServerPreference)
	ctx.SetOptions(openssl.NoSSLv3)

	err = ctx.LoadVerifyLocations(trustPath, "")
	if err != nil {
		return nil, err
	}

	certBytes, err := ioutil.ReadFile(certPath)
	if err != nil {
		return nil, err
	}

	cert, err := openssl.LoadCertificateFromPEM(certBytes)
	if err != nil {
		return nil, err
	}
	ctx.UseCertificate(cert)

	keyBytes, err := ioutil.ReadFile(keyPath)
	if err != nil {
		return nil, err
	}
	privKey, err := openssl.LoadPrivateKeyFromPEM(keyBytes)
	if err != nil {
		return nil, err
	}
	ctx.UsePrivateKey(privKey)

	addr := host + ":" + port

	// New context from files?
	context, err := openssl.NewCtxFromFiles(certPath, keyPath)
	if err != nil {
		return nil, err
	}

	_ = context.LoadVerifyLocations(trustPath, "")

	ctx = context

	conn, err := openssl.Dial("tcp", addr, ctx, dialOpts.Flags)
	if err != nil {
		log.Println("Error making openssl conn!")
		return nil, err
	}
	return conn, nil
}

see https://github.com/spacemonkeygo/openssl/blob/master/ctx.go