项目中要用到安全证书，生成CSR测试。

不多说，直接上干货。

1、什么是数字证书，这篇文章讲的不错，通俗易懂，简单明了。

http://www.ruanyifeng.com/blog/2011/08/what_is_a_digital_signature.html

2、使用keytool自带命令生成相关证书。

http://www.cnblogs.com/SirSmith/p/4996392.html

这些是网上的一些例子，使用后，自己可以跟着做一遍。

3、用java来生成csr数据，格式如下

-----BEGIN NEW CERTIFICATE REQUEST-----

MIICzDCCAbQCAQAwVzEOMAwGA1UEBhMFY2hpYW4xCzAJBgNVBAgTAmZ6MQswCQYDVQQHEwJmejEN

MAsGA1UEChMEeHlzajENMAsGA1UECxMEeHlzajENMAsGA1UEAxMEY2hlbjCCASIwDQYJKoZIhvcN

AQEBBQADggEPADCCAQoCggEBAIxCstBDP+snnSRNK9lRKippsvii4wD/d/MZnx2oj0xG+9wIkQ+f

4lHJ8WsmtvoYGTgQSWXX/eEOusDzBN7ZcQpPqXDBEYwcIxaM1Mz6gm5JnpnrGKWKXSSbP9M2Uh/I

J6zjAJT0eyhL5kJg2rP/wxbUBqDTqwgU8W6bwGmDQg6jaJQU9YY7jyLv1dMH1QKx07RnfQtbzgca

yVPjrvPAY0kdppF5cqYnS0jNptbK6SI1iaaELVZRYbnn/eXtUbLntUP5iyRsjyCBYjdTvEBgOg11

uK/B39q0on1LSOAnO1tSZC8ZOOhaxiwxqfPDpYb/wugPAB/vp6S7SFWa5DZWPusCAwEAAaAwMC4G

CSqGSIb3DQEJDjEhMB8wHQYDVR0OBBYEFAt7FLUGJBiuehAF3LiACcoHztzHMA0GCSqGSIb3DQEB

CwUAA4IBAQB4sp8UyWfAv1cdWYY4JqcPOAGqb3IapM8GTTMr6pROXsf3mRMSNhCHoBC0ykPfa5mL

PXlUR2m5zYcXuTBR0CoMR/wtUIsjikzbNThfnKX1DwtvrjxZmq9uaewEfDrez7MizteOMnIHcRFd

E/s4GxSNtjTgf5hRuxN08LG40m7QMr2Mqhl6yCWw4Q9fm+qrKASX9AyMe+r49zarOqMVOpATx0Tq

UCbl+wTekjny6c+N9GgbQlrtvlU0/QxypBkowosdKeuWFvS01wB8SbdOZorOvns3RBO9cRJc3Z8m

vrX/GC9wcrrCM/7MewpDJOzEcq1ycGLobU7I60BLF3jAH00R

-----END NEW CERTIFICATE REQUEST-----

相关代码

import java.io.ByteArrayOutputStream;

import java.io.IOException;

import java.io.PrintStream;

import java.security.InvalidKeyException;

import java.security.KeyPair;

import java.security.KeyPairGenerator;

import java.security.NoSuchAlgorithmException;

import java.security.PrivateKey;

import java.security.PublicKey;

import java.security.SecureRandom;

import java.security.Security;

import java.security.Signature;

import java.security.SignatureException;

import java.security.cert.CertificateException;

import org.bouncycastle.asn1.x500.X500Name;

import org.bouncycastle.jcajce.provider.keystore.PKCS12;

import org.bouncycastle.jce.provider.BouncyCastleProvider;

public class StoreUtils {

public KeyPair kp = null;

public String password = "";

public  String generateCSR(String alg,int size,String cn) throws NoSuchAlgorithmException, InvalidKeyException, IOException, CertificateException, SignatureException{

Security.addProvider(new BouncyCastleProvider());

String strCSR = "";

String sigAlg = "SHA1WithRSA";

try {

if (alg == null || alg.length() <= 0) {

sigAlg = "SHA1WithRSA";

} else {

sigAlg = alg;

int algSize = 2048;

if (size != 0) {

algSize = size;

}

KeyPairGenerator kpg = KeyPairGenerator.getInstance("RSA");

kpg.initialize(algSize, new SecureRandom());

this.kp = kpg.generateKeyPair();

PublicKey publicKey = this.kp.getPublic();

PrivateKey privateKey = this.kp.getPrivate();

sun.security.pkcs.PKCS10 pkcs10 = new sun.security.pkcs.PKCS10(

publicKey);

//PKCS10 pkcs10 = new PKCS10(publicKey);

Signature signature = Signature.getInstance(sigAlg);

signature.initSign(privateKey);

String CN = "defaultUserName";

if (cn != null && cn.length() > 0) {

CN = cn;

}

String DN = "CN=" + CN + ",C= CN";

@SuppressWarnings("restriction")

sun.security.x509.X500Name x500Name = new sun.security.x509.X500Name(

DN);

pkcs10.encodeAndSign(x500Name, signature);

ByteArrayOutputStream baos = new ByteArrayOutputStream();

PrintStream ps = new PrintStream(baos);

pkcs10.print(ps);

String strPEMCSR = baos.toString();

strCSR = strPEMCSR.replaceAll("\r|\n", "");

strCSR = strCSR.replaceAll(

"-----BEGIN NEW CERTIFICATE REQUEST-----", "");

strCSR = strCSR.replaceAll(

"-----END NEW CERTIFICATE REQUEST-----", "");

return strCSR;

}

} catch (Exception e) {

System.out.println(e.getMessage());

// TODO: handle exception

}

return strCSR;

}

public static void main(String[] args) throws InvalidKeyException, NoSuchAlgorithmException, CertificateException, SignatureException, IOException {

StoreUtils StoreUtils = new StoreUtils();

System.out.println(StoreUtils.generateCSR("SHA1WithRSA",0,""));

}

}

用到的包 bcprov-ext-jdk15on-1.49.jar