转换 PEM 格式的私钥

2022-01-25 00:00:00 ssl openssl ssl-certificate x509certificate java

我用 Java 代码创建了一个自签名证书并添加到 KeyStore.现在我想将创建的私钥和证书导出到 PEM 格式的文件中.是否有可能在没有任何第三方库的情况下实现这一目标?以下是我用于创建自签名证书的代码.

I have created a self-signed certificate with Java code and added into KeyStore. Now I want to export Private key and Certificate created, into a file in PEM format. Is it possible to achieve this without any third party library ? Below is the code I use for creating self-singed certificate.

  public void createSelfSignedSSLCertificate() {
    try {            
        final CertAndKeyGen keypair = new CertAndKeyGen("RSA", "SHA1WithRSA", null);
        final X500Name x500Name =
            new X500Name(commonName, organizationalUnit, organization, city, state, country);
        keypair.generate(keysize);
        final PrivateKey privKey = keypair.getPrivateKey();
        final X509Certificate[] chain = new X509Certificate[1];
        chain[0] = keypair.getSelfCertificate(x500Name, new Date(), validity * 24 * 60 * 60);
        final String alias = JettySSLConfiguration.SSL_CERTIFICATE_ALIAS;
        keyStore.setKeyEntry(alias, privKey, keyStorePassword.toCharArray(), chain);
    } catch (final Exception e) {
       // Handle Exception
    }       
}

任何关于如何将密钥和证书导出为 PEM 格式文件的建议都会非常有帮助.

Any suggestion of how to export the key and certificate into file with PEM format will be really helpful.

推荐答案

你使用Certificate.getEncoded() 和 Key.getEncoded() 获取 DER 并手动执行 base 64 编码和页眉/页脚，例如使用 DatatypeConverter.printBase64Binary() 或其他方式.比如:

You use Certificate.getEncoded() and Key.getEncoded() to get DER and do the base 64 encoding and header/footer manually, e.g. using DatatypeConverter.printBase64Binary() or some other way. Something like:

certpem = "-----BEGIN CERTIFICATE-----
" +
          DatatypeConverter.printBase64Binary(chain[0].getEncoded())) +
          "
-----END CERTIFICATE-----
";
keypem  = "-----BEGIN RSA PRIVATE KEY-----
" +
          DatatypeConverter.printBase64Binary(privKey.getEncoded())) +
          "
-----END RSA PRIVATE KEY-----
";

相关文章