茂名阿里云代理商：android 获取证书指纹

要在Android上获取证书的指纹，您可以使用以下代码片段：

import java.security.MessageDigest;
import java.security.NoSuchAlgorithmException;

public class CertificateUtils {
    public static String getCertificateFingerprint(Context context, String packageName) {
        try {
            Signature[] signatures = context.getPackageManager().getPackageInfo(packageName, PackageManager.GET_SIGNATURES).signatures;
            if (signatures.length > 0) {
                Signature signature = signatures[0];
                byte[] certBytes = signature.toByteArray();

                MessageDigest messageDigest = MessageDigest.getInstance("SHA1");
                byte[] digest = messageDigest.digest(certBytes);

                StringBuilder builder = new StringBuilder();
                for (byte b : digest) {
                    builder.append(Integer.toHexString((b & 0xFF) | 0x100).substring(1, 3));
                    builder.append(":");
                }

                return builder.toString().toUpperCase();
            }
        } catch (PackageManager.NameNotFoundException | NoSuchAlgorithmException e) {
            e.printStackTrace();
        }
        return null;
    }
}

然后，您可以在您的Activity类中使用以下代码来获取证书指纹：

String packageName = getApplicationContext().getPackageName();
String fingerprint = CertificateUtils.getCertificateFingerprint(getApplicationContext(), packageName);
if (fingerprint != null) {
    Log.d("Fingerprint", fingerprint);
} else {
    Log.e("Fingerprint", "Failed to get certificate fingerprint");
}

在上述代码中，packageName 是您想要获取指纹的应用程序的包名。请确保在使用上述代码之前，您已经获取了适当的权限（例如，<uses-permission android:name="android.permission.GET_PACKAGE_SIZE" />）。

在Android中获取证书指纹，可以通过以下代码实现：

import java.security.MessageDigest;
import java.security.cert.CertificateException;
import java.security.cert.X509Certificate;
import javax.net.ssl.X509TrustManager;

public class MyTrustManager implements X509TrustManager {
    @Override
    public void checkClientTrusted(X509Certificate[] chain, String authType) throws CertificateException {
        // 不做任何操作，接受任意客户端证书
    }

    @Override
    public void checkServerTrusted(X509Certificate[] chain, String authType) {
        // 获取证书指纹
        for (X509Certificate cert : chain) {
            try {
                MessageDigest md = MessageDigest.getInstance("SHA-1");
                byte[] publicKey = md.digest(cert.getEncoded());
                // 将字节数组转换为十六进制字符串
                StringBuilder hexString = new StringBuilder();
                for (byte b : publicKey) {
                    String appendString = Integer.toHexString(0xFF & b).toUpperCase();
                    if (appendString.length() == 1)
                        hexString.append("0");
                    hexString.append(appendString);
                    hexString.append(":");
                }
                String fingerprint = hexString.toString().substring(0, hexString.length() - 1);
                System.out.println("证书指纹：" + fingerprint);
            } catch (Exception e) {
                e.printStackTrace();
            }
        }
    }

    @Override
    public X509Certificate[] getAcceptedIssuers() {
        return new X509Certificate[0];
    }
}

然后在你的网络请求方法中使用上述TrustManager，可以在HttpsURLConnection中设置如下：

URL url = new URL("https://example.com");
HttpsURLConnection connection = (HttpsURLConnection) url.openConnection();
connection.setSSLSocketFactory(getSSLSocketFactory());
connection.setHostnameVerifier(new HostnameVerifier() {
    @Override
    public boolean verify(String hostname, SSLSession session) {
        // 不进行主机名验证，接受任意域名主机
        return true;
    }
});
connection.connect();

其中，getSSLSocketFactory()方法用于获取自定义的SSLSocketFactory，代码如下：

import java.security.KeyStore;
import javax.net.ssl.SSLContext;
import javax.net.ssl.TrustManager;
import javax.net.ssl.TrustManagerFactory;
import javax.net.ssl.X509TrustManager;

public class SSLUtil {
    public static javax.net.ssl.SSLSocketFactory getSSLSocketFactory() {
        X509TrustManager trustManager = new MyTrustManager();
        TrustManager[] trustManagers = new TrustManager[] { trustManager };
        SSLContext sslContext;
        try {
            sslContext = SSLContext.getInstance("TLS");
            sslContext.init(null, trustManagers, null);
            return sslContext.getSocketFactory();
        } catch (Exception e) {
            e.printStackTrace();
        }
        return null;
    }
}

以上代码通过自定义的TrustManager，实现了获取服务器证书指纹的功能。