基于 bouncycastle构建证书

导入依赖

<dependency>
    <groupId>org.bouncycastle</groupId>
    <artifactId>bcpkix-jdk18on</artifactId>
    <version>1.78.1</version>
</dependency>

代码

::: detail 示例代码

@Slf4j
@SuppressWarnings("unused")
public class CertificateGenerator {

    static {
        Security.addProvider(new BouncyCastleProvider());
    }

    @SneakyThrows
    public static String getCertContent(X509Certificate certificate){
        return   "-----BEGIN CERTIFICATE-----\n" +
                Base64.encode(certificate.getEncoded()) + "\n" +
                "-----BEGIN CERTIFICATE-----\n";
    }

    /**
     * 得到Cert内容
     * @param certFile 证书文件
     * @return Cert 字符
     */
    public static String getCertContent(File certFile){
        return FileUtil.readString(certFile, StandardCharsets.UTF_8);
    }

    /**
     * 加载证书
     * @param file  file
     * @return  X509Certificate X509Certificate
     */
    public static X509Certificate loadCertificate(File file) throws Exception{
        try (FileInputStream fileInputStream = new FileInputStream(file)) {
            return  loadCertificate(fileInputStream);
        }
    }

    /**
     * 加载证书
     * @param in  文件输入流
     * @return  X509Certificate X509Certificate
     */
    public static X509Certificate loadCertificate(InputStream in) throws Exception{
        Security.addProvider(new BouncyCastleProvider());
        CertificateFactory certFactory = CertificateFactory.getInstance("X.509","BC");
        return  (X509Certificate)certFactory.generateCertificate(in);
    }

    /**
     * 加载证书
     * @param text  证书字符
     * @return  X509Certificate X509Certificate
     */
    public static X509Certificate loadCertificate(String text) throws Exception {
        return  loadCertificate(text,true);
    }

    /**
     *  得到证书公钥
     * @param certFile  证书文件
     * @return  X509Certificate X509Certificate
     */
    public static PublicKey getCertificate(File certFile) throws Exception{
        X509Certificate x509Certificate = loadCertificate(certFile);
        return x509Certificate.getPublicKey();
    }

    /**
     *  得到证书公钥
     * @param cert 证书字符
     * @return  X509Certificate X509Certificate
     */
    public static PublicKey getCertificate(String cert) throws Exception {
        X509Certificate x509Certificate = loadCertificate(cert);
        return x509Certificate.getPublicKey();
    }

    /**
     * 加载证书
     * @param text  证书字符
     * @param includeHead  是否包括头
     * @return  X509Certificate X509Certificate
     */
    public static X509Certificate loadCertificate(String text, boolean includeHead) throws Exception {
        ByteArrayOutputStream bos = new ByteArrayOutputStream();
        if (includeHead){
            bos.write(text.getBytes());
        }else {
            bos.write(Base64.decode(text));
        }
        InputStream myInputStream = new ByteArrayInputStream(bos.toByteArray());
        return loadCertificate(myInputStream);
    }



    /**
     * 得到Csr内容
     * @param keyPair 密钥对
     * @param subject X500Name 示例
     * @return Csr 字符
     */
    @SneakyThrows
    public static  String getCsrContent(KeyPair keyPair , X500Name subject){
        // 将 CSR 导出为 PEM 格式
        try (ByteArrayOutputStream csr = getCsr(keyPair, subject)) {
            byte[] byteArray = csr.toByteArray();
            return new String(byteArray, StandardCharsets.UTF_8);
        }
    }

    /**
     * 写入到文件
     * @param path 写入文件路径
     * @param keyPair 密钥对
     * @param subject X500Name 实例
     */
    @SneakyThrows
    public static  void writeToFile(String path,KeyPair keyPair ,X500Name subject){
        // 将 CSR 导出为 PEM 格式
        try (ByteArrayOutputStream csr = getCsr(keyPair, subject);
             FileOutputStream fileOutputStream = new FileOutputStream(path)
        ) {
            fileOutputStream.write(csr.toByteArray());
            log.info("文件保存成功{} ", path);
        }
    }
    /**
     *  得到Csr
     * @param subject 使用人
     */
    @SneakyThrows
    private static  ByteArrayOutputStream getCsr(KeyPair keyPair ,X500Name subject){
        PKCS10CertificationRequest csr = getPkcs10CertificationRequest(keyPair, subject, keyPair.getPublic());
        ByteArrayOutputStream stream = new ByteArrayOutputStream();
        try (
                OutputStreamWriter outputStreamWriter = new OutputStreamWriter(stream);
                PemWriter pemWriter = new PemWriter(outputStreamWriter);
        ) {
            pemWriter.writeObject(new PemObject("CERTIFICATE REQUEST", csr.getEncoded()));
        }
        return stream;
    }


    /**
     * 获取PKCS 10认证请求
     * @param keyPair 密钥对
     * @param subject  X500Name
     * @param publicKey 公钥
     * @return PKCS10CertificationRequest
     * @throws OperatorCreationException 创建异常
     */
    private static PKCS10CertificationRequest getPkcs10CertificationRequest(KeyPair keyPair, X500Name subject, PublicKey publicKey) throws OperatorCreationException {
        //构建CSR
        JcaPKCS10CertificationRequestBuilder csrBuilder = new JcaPKCS10CertificationRequestBuilder(subject, publicKey);
        //签名 CSR
        ContentSigner contentSigner = new JcaContentSignerBuilder("SM3withSM2")
                .setProvider("BC").build(keyPair.getPrivate());
        return csrBuilder.build(contentSigner);
    }

    /**
     *  得到一组密钥对
     * @return SM2 密钥对
     */
    @SneakyThrows
    public static KeyPair getKeyPair()  {
        // 生成SM2密钥对
        // 获取一个椭圆曲线类型的密钥对生成器
        KeyPairGenerator keyPairGenerator = KeyPairGenerator.getInstance("EC", "BC");
        // 使用SM2参数初始化生成器
        keyPairGenerator.initialize(ECNamedCurveTable.getParameterSpec("sm2p256v1"), new SecureRandom());
        //得到秘钥对
        return keyPairGenerator.generateKeyPair();
    }



    /**
     * 获取私钥（16进制字符串，头部不带00长度共64）
     * @param privateKey 私钥
     * @return 私钥内容
     */
    public static String getPriKeyHexString(PrivateKey privateKey){
        //只获取私钥里的d，32字节
        BCECPrivateKey s=(BCECPrivateKey)privateKey;
        String priKeyHexString = Hex.toHexString(s.getD().toByteArray());
//        if(priKeyHexString.length() == 66 && "00".equals(priKeyHexString.substring(0, 2))){
//            return priKeyHexString.substring(2);
//        }
        return priKeyHexString;
    }


    /**
     * 获取公钥（16进制字符串，头部带04长度共130）
     * @param publicKey 公钥
     * @return 公钥内容
     */
    public static String getPubKeyHexString(PublicKey publicKey){
        BCECPublicKey p=(BCECPublicKey)publicKey;
        String pubKeyHexString = Hex.toHexString(p.getQ().getEncoded(false));
        if(pubKeyHexString.length() == 130 && pubKeyHexString.startsWith("04")){
            return pubKeyHexString.substring(2);
        }
        return pubKeyHexString;
    }


}