Question

我需要使用java以PEM格式生成RSA和DSA密钥对（公钥和私钥）。我希望以这种格式打开公钥和私钥文件：

-----开始公共关键----- MIIBIjANBgkqhkiG9w0BAQEFAAOCAQ8AMIIBCgKCAQEAryQICCl6NZ5gDKrnSztO 3Hy8PEUcuyvg / IKC + VcIo2SFFSf18a3IMYldIugqqqZCs4 / 4uVW3sbdLs / 6PfgdX 7O9D22ZiFWHPYA2k2N744MNiCD1UE + tJyllUhSblK48bn + v1oZHCM0nYQ2NqUkvS J + hwUU3RiWl7x3D2s9wSdNt7XUtW05a / FXehsPSiJfKvHJJnGOX0BgTvkLnkAOTd OrUZ / wK69Dzu4IvrN4vs9Nes8vbwPa / ddZEzGR0cQMt0JBkhk9kU / qwqUseP1QRJ 5I1jR4g8aYPL / ke9K35PxZWuDp3U0UPAZ3PjFAh + 5T + fc7gzCs9dPzSHloruU + GL FQIDAQAB ----- END PUBLIC KEY -----

我的公钥之前已经生成了我不想要的格式：

0Ÿ0*†H†÷0Ÿ0*†H†÷

好的，这是我的密钥生成代码：

private static void createKey()
        throws Exception {

            Security.addProvider(new org.bouncycastle.jce.provider.BouncyCastleProvider());

            BufferedReader in = new BufferedReader(new InputStreamReader(System.in));
            System.out.print("Password to encrypt the private key: ");
            String password = in.readLine();
            System.out.println("Generating an RSA keypair...");

            // Create an RSA key
            KeyPairGenerator keyPairGenerator = KeyPairGenerator.getInstance("RSA");
            keyPairGenerator.initialize(1024);
            KeyPair keyPair = keyPairGenerator.genKeyPair();

            System.out.println("Done generating the keypair.\n");

            // Now we need to write the public key out to a file
            System.out.print("Public key filename: ");
            String publicKeyFilename = "C:/Users/Joe/Desktop/" + in.readLine();

            // Get the encoded form of the public key so we can
            // use it again in the future. This is X.509 by default.
            byte[] publicKeyBytes = keyPair.getPublic().getEncoded();

            // Write the encoded public key out to the filesystem
            FileOutputStream fos = new FileOutputStream(publicKeyFilename);
            fos.write(publicKeyBytes);
            fos.close();

            // Now we need to do the same thing with the private key,
            // but we need to password encrypt it as well.
            System.out.print("Private key filename: ");
            String privateKeyFilename = "C:/Users/Joe/Desktop/" + in.readLine();

            // Get the encoded form. This is PKCS#8 by default.
            byte[] privateKeyBytes = keyPair.getPrivate().getEncoded();

            // Here we actually encrypt the private key
            byte[] encryptedPrivateKeyBytes =
            passwordEncrypt(password.toCharArray(),privateKeyBytes);

            fos = new FileOutputStream(privateKeyFilename);
            fos.write(encryptedPrivateKeyBytes);
            fos.close();
        }

谢谢你的帮助..

Answer 1

也许有点迟，但有我的解决方案。希望它能帮助别人。

byte[] publicKeyBytes = keyPair.getPublic().getEncoded();

这里你需要占用密钥字节并直接写入文件。所以你得到了合适的结果 - DER编码的文件。但是，PEM是Base64编码格式，每个符号和页眉/页脚都有换行符。

有实现此逻辑的代码：

String publicKeyContent = Base64.encode(publicKeyBytes);
String publicKeyFormatted = "-----BEGIN PUBLIC KEY-----" + System.lineSeparator();
for (final String row: 
        Splitter
            .fixedLength(64)
            .split(publicKeyContent)
    ) 
{
    publicKeyFormatted += row + System.lineSeparator();
}
publicKeyFormatted += "-----END PUBLIC KEY-----";

因此publicKeyFormatted将包含PEM编码的公钥字符串。

P.S。 Splitter是Guava lib中提供的类，但您可以通过简单的循环或以某种方式拆分字符串。

如何以PEM格式生成公钥和私钥

1 个答案: