在Android开发中，有时候我们需要为我们的应用程序添加自定义的SSL证书。SSL证书用于加密应用程序和服务器之间的通信，以确保数据的安全性。在某些情况下，比如应用程序需要访问自己搭建的服务器或者访问某些特殊的HTTPS网站时，我们可能需要添加自定义的SSL证书。
要在Android应用程序中动态添加多个SSL证书，可以按照以下步骤进行：
步骤1：将SSL证书文件保存在res/raw文件夹中
将你想要添加的SSL证书文件以.crt或者.pem的格式保存在res/raw文件夹中，可以使用任何文本编辑器创建或导出SSL证书。
步骤2：创建自定义的TrustManager
创建一个自定义的TrustManager类，该类将会被用于验证SSL证书的合法性。
```java
import java.io.InputStream;
import java.security.KeyStore;
import java.security.cert.Certificate;
import java.security.cert.CertificateFactory;
import java.security.cert.X509Certificate;
import javax.net.ssl.X509TrustManager;
public class CustomTrustManager implements X509TrustManager {
private final X509TrustManager defaultTrustManager;
private final X509Certificate[] customCertificates;
public CustomTrustManager(InputStream... certificates) throws Exception {
// 加载默认的TrustManager
KeyStore keyStore = KeyStore.getInstance(KeyStore.getDefaultType());
keyStore.load(null, null);
defaultTrustManager = TrustManagerFactory.getInstance(TrustManagerFactory.getDefaultAlgorithm()).getTrustManagers()[0];
// 加载自定义的证书
CertificateFactory certFactory = CertificateFactory.getInstance("X.509");
int i = 0;
customCertificates = new X509Certificate[certificates.length];
for (InputStream certificate : certificates) {
customCertificates[i] = (X509Certificate) certFactory.generateCertificate(certificate);
i++;
}
}
@Override
public void checkClientTrusted(X509Certificate[] chain, String authType) {
try {
defaultTrustManager.checkClientTrusted(chain, authType);
} catch (Exception e) {
throw new RuntimeException(e);
}
}
@Override
public void checkServerTrusted(X509Certificate[] chain, String authType) {
try {
defaultTrustManager.checkServerTrusted(chain, authType);
} catch (Exception e) {
for (X509Certificate certificate : chain) {
for (X509Certificate customCertificate : customCertificates) {
try {
certificate.verify(customCertificate.getPublicKey());
return;
} catch (Exception ignored) {}
}
}
throw new RuntimeException("Server certificate is not trusted.");
}
}
@Override
public X509Certificate[] getAcceptedIssuers() {
try {
return defaultTrustManager.getAcceptedIssuers();
} catch (Exception e) {
return new X509Certificate[0];
}
}
}
```
步骤3：为HttpClient添加自定义的SSL证书
使用HttpClient发送HTTP请求时，可以为HttpClient添加自定义的SSL证书。
```java
try {
// 加载自定义的SSL证书
InputStream certificate1 = context.getResources().openRawResource(R.raw.certificate1);
InputStream certificate2 = context.getResources().openRawResource(R.raw.certificate2);
CustomTrustManager customTrustManager = new CustomTrustManager(certificate1, certificate2);
SSLContext sslContext = SSLContext.getInstance("TLS");
sslContext.init(null, new TrustManager[]{customTrustManager}, null);
// 创建HttpClient，并设置自定义的SSL证书
HttpClient httpClient = AndroidHttpClient.newInstance("CustomHttpClient");
((AbstractHttpClient) httpClient).setSSLSocketFactory(sslContext.getSocketFactory());
// 发送HTTP请求
HttpResponse response = httpClient.execute(new HttpGet(url));
// 处理响应
// ...
} catch (Exception e) {
e.printStackTrace();
} finally {
// 关闭HttpClient
httpClient.close();
}
```
通过上述步骤，你就可以在Android应用程序中动态添加多个SSL证书了。在发送HTTP请求时，会使用自定义的TrustManager进行证书验证。
需要注意的是，动态添加SSL证书存在着一定的安全风险，因为你没有办法保证加载的证书是可信任的。所以在使用自定义的SSL证书时，请务必小心并确保证书的合法性。
