Java客户端与C++服务端的SSL双向认证

需求：客户端是JavaWeb的应用程序，会接受页面参数组装成自定义的XML协议格式发送给后端服务程序。C++服务端解析XML并执行命令。传送XML过程中可能会包含一些隐私数据，需要用SSL加密。我负责Java客户端。

准备：
在网上找了若干资料，大多是Java服务器C++客户端的，无奈只有用英文搜索些国外站点的资料。
1.下载openssl，做测试（Linux版本的安装）。
安装openssl
下载：openssl-0.9.7m.tar.gz
解压：tar xzvf openssl-0.9.7m.tar.gz
cd openssl-0.9.7m/
默认配置：./config
重新建立依赖关系：make depend
测试：make test
安装：make install
安装完成后就可以用openssl自带的s_server和s_client做测试了，很方便。

2.下载bcprov-jdk15-143.jar，早知道有这个东西就省事了。（BouncyCastle.org出品的Java开源SSL工具包）

步骤：
一、跑通Java客户端与C++ openssl双向通讯。
1.建立证书(注：需要输入信息的时候需要与CA生成时统一,但不能完全一致,姓名可以不一)
新建目录:mkdir openssl_demo2
拷贝 openssl-0.9.7m/apps/ 下的CA.sh、openssl.cnf 到 openssl_demo2 下
cd openssl_demo2

2.新建CA公私钥
./CA.sh -newca

该命令的工作：
创建目录：demoCA/ 、 demoCA/private/ 、 demoCA/certs/ 、demoCA/private/ 、demoCA/newcerts/
文件：demoCA/serial(写入“01”) 、demoCA/index.txt
创建CA公私钥:demoCA/cacert.pem、demoCA/private/cakey.pem

3.新建服务器端私钥+公钥签名请求
openssl req -newkey rsa:1024 -out serverreq.pem -keyout sslserverkey.pem

4.用CA私钥为服务端请求签名生成服务端证书
openssl ca -in serverreq.pem -out sslservercert.pem -config ./openssl.cnf

下面的步骤注意版本,java版本过低可能keytool做证书有问题。
OpenSSL 0.9.6m 17 Mar 2004
java -version -- Java(TM) SE Runtime Environment (build 1.6.0_03-b05)

5.生成客户端私钥并存入sslclient.keystore
keytool -genkey -alias sslclient -validity 365 -keyalg RSA -keysize 1024 -keystore sslclient.keystore -keypass 123456 -storepass 123456

6.从sslclient.keystore中提取客户端签名请求
keytool -certreq -alias sslclient -sigalg SHA1withRSA -file sslclient.csr -keypass 123456 -storepass 123456 -keystore sslclient.keystore

7.用CA私钥为服务端请求签名生成客户端证书
openssl ca -in sslclient.csr -out sslclient.crt -cert demoCA/cacert.pem -keyfile demoCA/private/cakey.pem -notext -config openssl.cnf

8.转换客户端证书格式
openssl x509 -in sslclient.crt -out sslclient.der -outform DER

9.sslclient.keystore导入根证书
keytool -import -v -trustcacerts -alias ca_root -file demoCA/cacert.pem -storepass 123456 -keystore sslclient.keystore

10.sslclient.keystore导入客户端证书
keytool -import -v -alias sslclient -file sslclient.der -keypass 123456 -storepass 123456 -keystore sslclient.keystore

11.运行程序
运行openssl自带测试服务端：openssl s_server -cert sslservercert.pem -key sslserverkey.pem -CAfile demoCA/cacert.pem -state -Verify 1 -ssl3
运行Java客户端（略）。

（上面的步骤参考了这篇文章：http://www.blogjava.net/alwayscy/archive/2009/02/03/85161.html
由于下面的问题，不能完全采用上面的方案。）

二、问题：由于证书的生产和颁发是由另外一个VC程序统一管理的，所以不可能为了我的Java程序而做一个额外的功能。证书颁发程序是将CA根证书、客户端证书和客户端私钥下发到系统某个目录下然后我去取用的。麻烦在程序生成的证书都是PEM格式的，不能直接导入Java的JKS库，需要做个转换。
1.在网上的几篇文章分别搜到些 PEM证书+私钥合并为pkcs12格式密钥库、pkcs12格式密钥库导入JKS密钥库、CA证书导入JKS密钥库的文章，于是整理了一下做了个小例子。

package change_format;

import java.security.KeyStore;
import java.security.Key;
import java.security.cert.Certificate;
import java.security.cert.CertificateFactory;
import java.security.cert.X509Certificate;
import java.io.*;
import java.util.*;

public class ConvertPEMToJKS {
// certificate store format
public static final String PKCS12 = "PKCS12";

public static final String JKS = "JKS";

// PKCS12 keystore properties
public static final String INPUT_KEYSTORE_FILE = "src/change_format/keystore.pkcs12";

public static final String KEYSTORE_PASSWORD = "123456";

// JKS output file
public static final String OUTPUT_KEYSTORE_FILE = "src/change_format/keystore.jks";

public static final String CACERT_FILE = "src/change_format/ca2.crt";

public static final String PEMPRIKEY_FILE = "src/change_format/clientssl.pri";

public static final String PEMPUBKEY_FILE = "src/change_format/clientssl.crt";

public static void pktojks() {
try {
KeyStore inputKeyStore = KeyStore.getInstance("PKCS12");
FileInputStream fis = new FileInputStream(INPUT_KEYSTORE_FILE);

// If the keystore password is empty(""), then we have to set
// to null, otherwise it won't work!!!
char[] nPassword = null;
if ((KEYSTORE_PASSWORD == null)
|| KEYSTORE_PASSWORD.trim().equals("")) {
nPassword = null;
} else {
nPassword = KEYSTORE_PASSWORD.toCharArray();
}
inputKeyStore.load(fis, nPassword);
fis.close();

// System.out.println("keystore type=" + inputKeyStore.getType());

// ----------------------------------------------------------------------
// get a JKS keystore and initialize it.
KeyStore outputKeyStore = KeyStore.getInstance("JKS");
outputKeyStore.load(null, "123456".toCharArray());
// Now we loop all the aliases, we need the alias to get keys.
// It seems that this value is the "Friendly name" field in the
// detals tab <-- Certificate window <-- view <-- Certificate
// Button <-- Content tab <-- Internet Options <-- Tools menu
// In MS IE 6.

Enumeration enume = inputKeyStore.aliases();
while (enume.hasMoreElements()) // we are readin just one
// certificate.
{
String keyAlias = (String) enume.nextElement();
// System.out.println("alias=[" + keyAlias + "]");
if (inputKeyStore.isKeyEntry(keyAlias)) {
Key key = inputKeyStore.getKey(keyAlias, nPassword);
Certificate[] certChain = inputKeyStore
.getCertificateChain(keyAlias);
outputKeyStore.setKeyEntry(keyAlias, key, "123456"
.toCharArray(), certChain);
}
}
FileOutputStream out = new FileOutputStream(OUTPUT_KEYSTORE_FILE);
outputKeyStore.store(out, nPassword);
out.close();
} catch (Exception e) {
e.printStackTrace();
}
}

public static void jksaddcacert() {
try {
FileInputStream cacertfile = new FileInputStream(CACERT_FILE);
FileInputStream oldjks = new FileInputStream(OUTPUT_KEYSTORE_FILE);

CertificateFactory cf = CertificateFactory.getInstance("X.509");
X509Certificate cert = (X509Certificate) cf
.generateCertificate(cacertfile);
cacertfile.close();

KeyStore.TrustedCertificateEntry trustedEntry = new KeyStore.TrustedCertificateEntry(
cert);

KeyStore outputKeyStore = KeyStore.getInstance("JKS");
outputKeyStore.load(oldjks, "123456".toCharArray());
oldjks.close();

outputKeyStore.setEntry("ca_root", trustedEntry, null);
FileOutputStream out = new FileOutputStream(OUTPUT_KEYSTORE_FILE);
outputKeyStore.store(out, KEYSTORE_PASSWORD.toCharArray());
out.close();
} catch (Exception e) {
e.printStackTrace();
}
}

private static final String localDir = "src\\change_format\\";

public static void pemaddpk() {
try {
Runtime rt = Runtime.getRuntime();
Process ps = null;
String exeStr = "openssl pkcs12 -export -in " + localDir
+ "clientssl.crt -inkey " + localDir
+ "clientssl.pri -out " + localDir
+ "keystore.pkcs12 -passout pass:123456";
System.out.println(exeStr);

ps = rt.exec(exeStr);
ps.waitFor();

int i = ps.exitValue();
if (i == 0) {
System.out.println("Convert PKCS12 Sucess!");
} else {
System.out.println("Convert PKCS12 Error!");
}
} catch (InterruptedException e) {
e.printStackTrace();
} catch (IOException e) {
e.printStackTrace();
}
}

public static void main(String[] args) {
ConvertPEMToJKS.pemaddpk();
ConvertPEMToJKS.pktojks();
ConvertPEMToJKS.jksaddcacert();
}
}

2. 如上例子中遇到一个问题，就是我程序所在的部署机将来需要安装openssl才能执行pemaddpk()方法中的openssl脚本；或者需要部署人员额外对证书颁发程序颁发的证书做个转化。这两种方法都是比较繁琐的，终于找到BouncyCastle的开源SSL工具包可以直接读入PEM格式并导入JKS，真是Java做OpenSSL的福音啊。

将bcprov-jdk15-143.jar导入工作路径，我抽出了一小段代码，以后要用到SSL的话可以方便的调用。

SSLContextBuild.java :
import java.io.FileInputStream;
import java.io.FileReader;
import java.io.IOException;
import java.security.KeyPair;
import java.security.KeyStore;
import java.security.Security;
import java.security.cert.Certificate;
import java.security.cert.CertificateFactory;
import java.security.cert.X509Certificate;
import java.util.Properties;
import javax.net.ssl.KeyManagerFactory;
import javax.net.ssl.SSLContext;
import javax.net.ssl.TrustManagerFactory;
import org.bouncycastle.openssl.PEMReader;
import org.bouncycastle.openssl.PasswordFinder;

public class SSLContextBuild {
public static SSLContext getSSLContext() {
// 获取证书路径
Properties prop = new Properties();
try {
//这里的路径是放在javaweb应用程序的web-inf/class下的
prop.load(SSLContextBuild.class.getClassLoader()
.getResourceAsStream("SSLCertPath.properties"));
} catch (IOException e) {
e.printStackTrace();
}

SSLContext sslContext = null;
try {
// 设定Security的Provider提供程序
Security
.addProvider(new org.bouncycastle.jce.provider.BouncyCastleProvider());

// 读入客户端证书
PEMReader pr = new PEMReader(new FileReader(prop.get("client_cert")
.toString()));
X509Certificate cert = (X509Certificate) pr.readObject();
pr.close();

// 读入客户端私钥
PEMReader kr = new PEMReader(new FileReader(prop.get(
"client_privatekey").toString()), new PasswordFinder() {
public char[] getPassword() {
return "".toCharArray();
}
});
KeyPair key = (KeyPair) kr.readObject();
kr.close();

// 建立空JKS
KeyStore ksKeys = KeyStore.getInstance("JKS");
ksKeys.load(null, "123456".toCharArray());

// 导入客户端私钥和证书
ksKeys.setKeyEntry("clientkey", key.getPrivate(), "123456"
.toCharArray(), new Certificate[] { cert });
ksKeys.setCertificateEntry("clientcert", cert);

// 导入根证书作为trustedEntry,待改进代码,此处没用bouncycastle的API,用了应该能简化点
FileInputStream cacertfile = new FileInputStream(prop.get("cacert")
.toString());

CertificateFactory cf = CertificateFactory.getInstance("X.509");
X509Certificate cacert = (X509Certificate) cf
.generateCertificate(cacertfile);
cacertfile.close();

KeyStore.TrustedCertificateEntry trustedEntry = new KeyStore.TrustedCertificateEntry(
cacert);
ksKeys.setEntry("ca_root", trustedEntry, null);

// 构建KeyManager、TrustManager
KeyManagerFactory kmf = KeyManagerFactory
.getInstance(KeyManagerFactory.getDefaultAlgorithm());
kmf.init(ksKeys, "123456".toCharArray());
TrustManagerFactory tmf = TrustManagerFactory
.getInstance(TrustManagerFactory.getDefaultAlgorithm());
tmf.init(ksKeys);

// 构建SSLContext
sslContext = SSLContext.getInstance("SSL");
sslContext.init(kmf.getKeyManagers(), tmf.getTrustManagers(), null);

} catch (Exception e) {
e.printStackTrace();
}

return sslContext;
}
}

SSLCertPath.properties :
cacert=E:\\Ben\\ca2.crt
client_cert=E:\\Ben\\clientcert.crt
client_privatekey=E:\\Ben\\clientkey.pri

调用的时候：
try {
sslSocket = (SSLSocket) SSLContextBuild.getSSLContext()
.getSocketFactory()
.createSocket(HOST, PORT); //HOST like "192.168.1.X";PORT like 8888

sslSocket.setEnabledProtocols(new String[] { "SSLv3" }); //注意此处要与你服务器端的程序设定一致。现在比较常用的协议是SSLv3/TLSv1。
} catch (Exception e) {
e.printStackTrace();
}

整了一个多星期，从完全没有SSL的概念，到将其融入代码，真是要感谢网络啊，哈哈。很有感觉哦！