如何在Apache HttpClient中使用SSL客户端证书？

我认为主要区别在于，在Java中，通常将密钥和证书放在密钥存储区中，然后从那里使用它。就像您提到的那样，人们经常希望为此使用单独的库，例如提到的httpcomponents客户端（就像您在python示例中使用请求库一样）。

这是一个使用前面提到的库使用密钥库中的客户机证书的示例：

import org.apache.http.HttpEntity;
import org.apache.http.HttpResponse;
import org.apache.http.client.HttpClient;
import org.apache.http.client.methods.HttpGet;
import org.apache.http.impl.client.HttpClients;
import org.apache.http.ssl.SSLContexts;
import org.apache.http.util.EntityUtils;
import org.junit.Test;

import javax.net.ssl.SSLContext;
import java.io.InputStream;
import java.security.KeyStore;

import static org.junit.Assert.assertEquals;
import static org.junit.Assert.assertNotNull;

public class MyClientCertTest {

    private static final String KEYSTOREPATH = "/clientkeystore.jks"; // or .p12
    private static final String KEYSTOREPASS = "keystorepass";
    private static final String KEYPASS = "keypass";

    KeyStore readStore() throws Exception {
        try (InputStream keyStoreStream = this.getClass().getResourceAsStream(KEYSTOREPATH)) {
            KeyStore keyStore = KeyStore.getInstance("JKS"); // or "PKCS12"
            keyStore.load(keyStoreStream, KEYSTOREPASS.toCharArray());
            return keyStore;
        }
    }
    @Test
    public void readKeyStore() throws Exception {
        assertNotNull(readStore());
    }
    @Test
    public void performClientRequest() throws Exception {
        SSLContext sslContext = SSLContexts.custom()
                .loadKeyMaterial(readStore(), KEYPASS.toCharArray()) // use null as second param if you don't have a separate key password
                .build();

        HttpClient httpClient = HttpClients.custom().setSSLContext(sslContext).build();
        HttpResponse response = httpClient.execute(new HttpGet("https://slsh.iki.fi/client-certificate/protected/"));
        assertEquals(200, response.getStatusLine().getStatusCode());
        HttpEntity entity = response.getEntity();

        System.out.println("----------------------------------------");
        System.out.println(response.getStatusLine());
        EntityUtils.consume(entity);
    }
}

Maven pom用于依赖版本：

<?xml version="1.0" encoding="UTF-8"?>
<project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
    xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
    <modelVersion>4.0.0</modelVersion>

    <groupId>com.acme</groupId>
    <artifactId>httptests</artifactId>
    <version>0.0.1-SNAPSHOT</version>
    <properties>
        <maven.compiler.source>1.8</maven.compiler.source>
        <maven.compiler.target>1.8</maven.compiler.target>
    </properties>
    <dependencies>
        <dependency>
            <groupId>org.apache.httpcomponents</groupId>
            <artifactId>httpclient</artifactId>
            <version>4.5.3</version>
        </dependency>
        <dependency>
            <groupId>junit</groupId>
            <artifactId>junit</artifactId>
            <version>4.12</version>
            <scope>test</scope>
        </dependency>
    </dependencies>
    <build>
        <plugins>
            <plugin>
                <groupId>org.apache.maven.plugins</groupId>
                <artifactId>maven-surefire-plugin</artifactId>
                <version>2.9</version>
                <!-- this is not needed, but useful if you want to debug what's going
                     on with your connection -->
                <configuration>
                    <argLine>-Djavax.net.debug=all</argLine>
                </configuration>
            </plugin>
        </plugins>
    </build>
</project>

我还发布了一个简单的测试页，用于测试客户端证书。

只是为了证明它是可以做到的，下面是一个示例，该示例仅使用标准Java API来使用客户端证书，而没有额外的库。

import org.junit.Test;

import javax.net.ssl.HttpsURLConnection;
import javax.net.ssl.KeyManager;
import javax.net.ssl.KeyManagerFactory;
import javax.net.ssl.SSLContext;
import java.io.BufferedReader;
import java.io.InputStream;
import java.io.InputStreamReader;
import java.net.URL;
import java.security.KeyStore;

public class PlainJavaHTTPS2Test {

    @Test
    public void testJKSKeyStore() throws Exception {
        final String KEYSTOREPATH = "clientkeystore.jks";
        final char[] KEYSTOREPASS = "keystorepass".toCharArray();
        final char[] KEYPASS = "keypass".toCharArray();

        try (InputStream storeStream = this.getClass().getResourceAsStream(KEYSTOREPATH)) {
            setSSLFactories(storeStream, "JKS", KEYSTOREPASS, KEYPASS);
        }
        testPlainJavaHTTPS();
    }
    @Test
    public void testP12KeyStore() throws Exception {
        final String KEYSTOREPATH = "clientkeystore.p12";
        final char[] KEYSTOREPASS = "keystorepass".toCharArray();
        final char[] KEYPASS = "keypass".toCharArray();

        try (InputStream storeStream = this.getClass().getResourceAsStream(KEYSTOREPATH)) {
            setSSLFactories(storeStream, "PKCS12", KEYSTOREPASS, KEYPASS);
        }
        testPlainJavaHTTPS();
    }
    private static void setSSLFactories(InputStream keyStream, String keystoreType, char[] keyStorePassword, char[] keyPassword) throws Exception
    {
        KeyStore keyStore = KeyStore.getInstance(keystoreType);

        keyStore.load(keyStream, keyStorePassword);

        KeyManagerFactory keyFactory =
                KeyManagerFactory.getInstance(KeyManagerFactory.getDefaultAlgorithm());

        keyFactory.init(keyStore, keyPassword);

        KeyManager[] keyManagers = keyFactory.getKeyManagers();

        SSLContext sslContext = SSLContext.getInstance("SSL");
        sslContext.init(keyManagers, null, null);
        SSLContext.setDefault(sslContext);
    }

    public void testPlainJavaHTTPS() throws Exception {
        String httpsURL = "https://slsh.iki.fi/client-certificate/protected/";
        URL myUrl = new URL(httpsURL);
        HttpsURLConnection conn = (HttpsURLConnection)myUrl.openConnection();
        try (InputStream is = conn.getInputStream()) {
            InputStreamReader isr = new InputStreamReader(is);
            BufferedReader br = new BufferedReader(isr);

            String inputLine;

            while ((inputLine = br.readLine()) != null) {
                System.out.println(inputLine);
            }
        }
    }
}

这是代码最少的第三个版本，但是它依赖于以下事实：a）密钥库是磁盘上的文件，而不是jar中的文件，并且b）密钥密码必须与密钥库密码相同。

import org.junit.BeforeClass;
import org.junit.Test;

import java.net.URL;
import java.io.*;
import javax.net.ssl.HttpsURLConnection;

public class PlainJavaHTTPSTest {

    @BeforeClass
    public static void setUp() {
        System.setProperty("javax.net.ssl.keyStore", "/full/path/to/clientkeystore-samepassword.jks");
        System.setProperty("javax.net.ssl.keyStorePassword", "keystorepass");
    }

    @Test
    public void testPlainJavaHTTPS() throws Exception {
        String httpsURL = "https://slsh.iki.fi/client-certificate/protected/";
        URL myUrl = new URL(httpsURL);
        HttpsURLConnection conn = (HttpsURLConnection)myUrl.openConnection();
        try (InputStream is = conn.getInputStream()) {
            InputStreamReader isr = new InputStreamReader(is);
            BufferedReader br = new BufferedReader(isr);

            String inputLine;

            while ((inputLine = br.readLine()) != null) {
                System.out.println(inputLine);
            }
        }
    }
}

当然，也可以将上面在代码中设置的属性指定为启动参数-Djavax.net.ssl.keyStore=/full/path/to/clientkeystore-samepassword.jks和-Djavax.net.ssl.keyStorePassword=keystorepass。