数字证书转换

keystore证书转换

算法 JDK Windows SUN 

常用的证书库：
JKS和JCEKS是Java密钥库(KeyStore)的两种比较常见类型，JKS的Provider是SUN，在每个版本的JDK中都有，JCEKS的Provider是SUNJCE，1.4后我们都能够直接使用它。
JCEKS在安全级别上要比JKS强，使用的Provider是JCEKS(推荐)，尤其在保护KeyStore中的私钥上（使用TripleDES）
PKCS#12（PFX）是公钥加密标准，它规定了可包含所有私钥、公钥和证书。其以二进制格式存储，在windows中可以直接导入到密钥区，注意，PKCS#12的密钥库保护密码同时也用于保护Key。
BKS来自BouncyCastleProvider，它使用的也是TripleDES来保护密钥库中的Key，它能够防止证书库被不小心修改（Keystore的keyentry改掉1个bit都会产生错误），BKS能够跟JKS互操作。
UBER比较特别，当密码是通过命令行提供的时候，它只能跟keytool交互。整个keystore是通过PBE/SHA1/Twofish加密，因此keystore能够防止被误改、察看以及校验。SunJDK允许你在不提供密码的情况下直接加载一个Keystore，类似cacerts，UBER不允许这种情况。

PFX转成JKS

Java代码   

    public static final String PKCS12 = "PKCS12";
    public static final String JKS = "JKS";
/**
     * PFX证书转换为JKS(Java Key Store)
     * 
     * @param pfxPassword
     *            PFX证书密码
     * @param pfxFilePath
     *            PFX证书路径
     * @param jksPassword
     *            JKS证书密码
     * @param jksFilePath
     *            JKS证书路径
     */
    public static void covertPFXtoJKS(String pfxPassword, String pfxFilePath, String jksPassword, String jksFilePath)
    {
        FileInputStream fis = null;
        FileOutputStream out = null;
        try
        {
            // 加载PFX证书
            KeyStore inputKeyStore = KeyStore.getInstance(PKCS12);
            fis = new FileInputStream(pfxFilePath);
            char[] inPassword = pfxPassword == null ? null : pfxPassword.toCharArray();
            char[] outPassword = jksPassword == null ? null : jksPassword.toCharArray();
            inputKeyStore.load(fis, inPassword);

            KeyStore outputKeyStore = KeyStore.getInstance(JKS);
            outputKeyStore.load(null, outPassword);
            Enumeration<String> enums = inputKeyStore.aliases();
            while (enums.hasMoreElements())
            {
                String keyAlias = enums.nextElement();
                if (inputKeyStore.isKeyEntry(keyAlias))
                {
                    Key key = inputKeyStore.getKey(keyAlias, inPassword);
                    Certificate[] certChain = inputKeyStore.getCertificateChain(keyAlias);
                    outputKeyStore.setKeyEntry(keyAlias, key, pfxPassword.toCharArray(), certChain);
                }
            }
            out = new FileOutputStream(jksFilePath);
            outputKeyStore.store(out, outPassword);
        } catch (Exception e)
        {
            e.printStackTrace();
        } finally
        {
            try
            {
                if (fis != null)
                {
                    fis.close();
                }
                if (out != null)
                {
                    out.close();
                }
            } catch (Exception e)
            {
                e.printStackTrace();
            }
        }
    }

从JKS格式转换为PKCS12格式

Java代码   

/**
     * 从JKS格式转换为PKCS12格式
     * 
     * @param jksFilePath
     *            String JKS格式证书库路径
     * @param jksPasswd
     *            String JKS格式证书库密码
     * @param pfxFilePath
     *            String PKCS12格式证书库保存文件夹
     * @param pfxPasswd
     *            String PKCS12格式证书库密码
     */
    public void covertJSKToPFX(String jksFilePath, String jksPasswd, String pfxFolderPath, String pfxPasswd) throws Throwable
    {
        FileInputStream fis = null;
        try
        {
            KeyStore inputKeyStore = KeyStore.getInstance(JKS);
            fis = new FileInputStream(jksFilePath);
            char[] srcPwd = jksPasswd == null ? null : jksPasswd.toCharArray();
            char[] destPwd = pfxPasswd == null ? null : pfxPasswd.toCharArray();
            inputKeyStore.load(fis, srcPwd);

            KeyStore outputKeyStore = KeyStore.getInstance(PKCS12);
            Enumeration<String> enums = inputKeyStore.aliases();
            while (enums.hasMoreElements())
            {
                String keyAlias = (String) enums.nextElement();
                System.out.println("alias=[" + keyAlias + "]");
                outputKeyStore.load(null, destPwd);
                if (inputKeyStore.isKeyEntry(keyAlias))
                {
                    Key key = inputKeyStore.getKey(keyAlias, srcPwd);
                    Certificate[] certChain = inputKeyStore.getCertificateChain(keyAlias);
                    outputKeyStore.setKeyEntry(keyAlias, key, destPwd, certChain);
                }
                String fName = pfxFolderPath + "_" + keyAlias + ".pfx";
                FileOutputStream out = new FileOutputStream(fName);
                outputKeyStore.store(out, destPwd);
                out.close();
                outputKeyStore.deleteEntry(keyAlias);
            }
        } finally
        {
            try
            {
                if (fis != null)
                {
                    fis.close();
                }
            } catch (Exception e)
            {
                e.printStackTrace();
            }
        }
    }

列出所有X509证书的属性，功能类似于keytool -list

Java代码

/**
     * 列出JKS库内所有X509证书的属性
     *
     * @param jksFilePath
     *            证书库路径
     * @param jksPasswd
     *            证书库密码
     * @param algName
     *            库类型
     */
    public static void listAllCerts(String jksFilePath, String jksPasswd, String algName)
    {
        try
        {
            char[] srcPwd = jksPasswd == null ? null : jksPasswd.toCharArray();
            FileInputStream in = new FileInputStream(jksFilePath);
            KeyStore ks = KeyStore.getInstance(algName);
            ks.load(in, srcPwd);
            Enumeration<String> e = ks.aliases();
            while (e.hasMoreElements())
            {
                String alias = e.nextElement();
                Certificate cert = ks.getCertificate(alias);
                if (cert instanceof X509Certificate)
                {
                    X509Certificate X509Cert = (X509Certificate) cert;
                    System.out.println("**************************************");
                    System.out.println("版本号:" + X509Cert.getVersion());
                    System.out.println("序列号:" + X509Cert.getSerialNumber().toString(16));
                    System.out.println("主体名：" + X509Cert.getSubjectDN());
                    System.out.println("签发者：" + X509Cert.getIssuerDN());
                    System.out.println("有效期：" + X509Cert.getNotBefore());
                    System.out.println("签名算法：" + X509Cert.getSigAlgName());
                    System.out.println("输出证书信息:\n" + X509Cert.toString());
                    System.out.println("**************************************");
                }
            }
        } catch (Exception e)
        {
            e.printStackTrace();
        }
    }