Android 使用 Https问题解决（SSLHandshakeException） _Exception

观书散遗帙，探古穷至妙。这篇文章主要讲述Android 使用 Https问题解决（SSLHandshakeException）相关的知识，希望能为你提供帮助。

title

date

tags

android 5.0以下TLS1.x SSLHandshakeException

2016-11-30 12:17:02 -0800

Android

TLSv1.x

最近把App的所有请求都换成Https,在测试的时候,部分手机发现请求失败,失败的异常信息如下:

javax.net.ssl.SSLHandshakeException: javax.net.ssl.SSLProtocolException: SSL handshake aborted: ssl=0x783e8e70: Failure in SSL library, usually a protocol error error:14077102:SSL routines:SSL23_GET_SERVER_HELLO:unsupported protocol (external/openssl/ssl/s23_clnt.c:714 0x71a20cf8:0x00000000)

该异常为握手失败,但是为什么有的手机可以成功有的手机又失败了呢,首先查看我们服务端接口TLS支持的版本为1.x,后来发现失败的手机都是5.x以下的版本,推测应该是和这个有关,然后查阅官方文档,SSLSocket中有提到TLS版本和Android SDK版本的对应表,如下:

Protocol	Supported (API Levels)	Enabled by default (API Levels)
SSLv3	1+	1+
TLSv1	1+	1+
TLSv1.1	16+	20+
TLSv1.2	16+	20+

【Android 使用 Https问题解决（SSLHandshakeException）】
通过这个表看到,TLSv1.x(1.1,1.2)Android默认从API16开始支持,而从API20开始默认可用,这就可以解释之前为什么5.x以下手机在进行请求时失败了。
知道问题的原因,我们就要解决,当然服务端可以支持TLSv1版本,这样我们就都可以请求成功,但是这并不是最好的解决方法,我们当然要让我们的App支持新的TLS协议才对。
通过官方文档发现Cipher suites有的也是API20+支持或者默认可用,所以我们如果想支持TLSv1.x版本,可能需要给低版本添加Cipher suites,所以我们需要自定义SSLSocketFactory,自定义的SSLSocketFactory如下:

public class SSL extends SSLSocketFactory { private SSLSocketFactory defaultFactory; // Android 5.0+ (API level21) provides reasonable default settings // but it still allows SSLv3 // https://developer.android.com/about/versions/android-5.0-changes.html#ssl static String protocols[] = null, cipherSuites[] = null; static { try { SSLSocket socket = (SSLSocket) SSLSocketFactory.getDefault().createSocket(); if (socket != null) { /* set reasonable protocol versions */ // - enable all supported protocols (enables TLSv1.1 and TLSv1.2 on Android < 5.0) // - remove all SSL versions (especially SSLv3) because they‘re insecure now List< String> protocols = new LinkedList< > (); for (String protocol : socket.getSupportedProtocols()) if (!protocol.toUpperCase().contains("SSL")) protocols.add(protocol); SSL.protocols = protocols.toArray(new String[protocols.size()]); /* set up reasonable cipher suites */ if (Build.VERSION.SDK_INT < Build.VERSION_CODES.LOLLIPOP) { // choose known secure cipher suites List< String> allowedCiphers = Arrays.asList( // TLS 1.2 "TLS_RSA_WITH_AES_256_GCM_SHA384", "TLS_RSA_WITH_AES_128_GCM_SHA256", "TLS_ECDHE_ECDSA_WITH_AES_128_CBC_SHA256", "TLS_ECDHE_ECDSA_WITH_AES_128_GCM_SHA256", "TLS_ECDHE_ECDSA_WITH_AES_256_GCM_SHA384", "TLS_ECDHE_RSA_WITH_AES_128_CBC_SHA256", "TLS_ECHDE_RSA_WITH_AES_128_GCM_SHA256", // maximum interoperability "TLS_RSA_WITH_3DES_EDE_CBC_SHA", "TLS_RSA_WITH_AES_128_CBC_SHA", // additionally "TLS_RSA_WITH_AES_256_CBC_SHA", "TLS_ECDHE_ECDSA_WITH_3DES_EDE_CBC_SHA", "TLS_ECDHE_ECDSA_WITH_AES_128_CBC_SHA", "TLS_ECDHE_RSA_WITH_3DES_EDE_CBC_SHA", "TLS_ECDHE_RSA_WITH_AES_128_CBC_SHA"); List< String> availableCiphers = Arrays.asList(socket.getSupportedCipherSuites()); // take all allowed ciphers that are available and put them into preferredCiphers HashSet< String> preferredCiphers = new HashSet< > (allowedCiphers); preferredCiphers.retainAll(availableCiphers); /* For maximum security, preferredCiphers should *replace* enabled ciphers (thus disabling * ciphers which are enabled by default, but have become unsecure), but I guess for * the security level of DAVdroid and maximum compatibility, disabling of insecure * ciphers should be a server-side task */ // add preferred ciphers to enabled ciphers HashSet< String> enabledCiphers = preferredCiphers; enabledCiphers.addAll(new HashSet< > (Arrays.asList(socket.getEnabledCipherSuites()))); SSL.cipherSuites = enabledCiphers.toArray(new String[enabledCiphers.size()]); } } } catch (IOException e) { throw new RuntimeException(e); } }public SSL(X509TrustManager tm) { try { SSLContext sslContext = SSLContext.getInstance("TLS"); sslContext.init(null, (tm != null) ? new X509TrustManager[]{tm} : null, null); defaultFactory = sslContext.getSocketFactory(); } catch (GeneralSecurityException e) { throw new AssertionError(); // The system has no TLS. Just give up. } }private void upgradeTLS(SSLSocket ssl) { // Android 5.0+ (API level21) provides reasonable default settings // but it still allows SSLv3 // https://developer.android.com/about/versions/android-5.0-changes.html#ssl if (protocols != null) { ssl.setEnabledProtocols(protocols); } if (Build.VERSION.SDK_INT < Build.VERSION_CODES.LOLLIPOP & & cipherSuites != null) { ssl.setEnabledCipherSuites(cipherSuites); } }@Override public String[] getDefaultCipherSuites() { return cipherSuites; }@Override public String[] getSupportedCipherSuites() { return cipherSuites; }@Override public Socket createSocket(Socket s, String host, int port, boolean autoClose) throws IOException { Socket ssl = defaultFactory.createSocket(s, host, port, autoClose); if (ssl instanceof SSLSocket) upgradeTLS((SSLSocket) ssl); return ssl; }@Override public Socket createSocket(String host, int port) throws IOException, UnknownHostException { Socket ssl = defaultFactory.createSocket(host, port); if (ssl instanceof SSLSocket) upgradeTLS((SSLSocket) ssl); return ssl; }@Override public Socket createSocket(String host, int port, InetAddress localHost, int localPort) throws IOException, UnknownHostException { Socket ssl = defaultFactory.createSocket(host, port, localHost, localPort); if (ssl instanceof SSLSocket) upgradeTLS((SSLSocket) ssl); return ssl; }@Override public Socket createSocket(InetAddress host, int port) throws IOException { Socket ssl = defaultFactory.createSocket(host, port); if (ssl instanceof SSLSocket) upgradeTLS((SSLSocket) ssl); return ssl; }@Override public Socket createSocket(InetAddress address, int port, InetAddress localAddress, int localPort) throws IOException { Socket ssl = defaultFactory.createSocket(address, port, localAddress, localPort); if (ssl instanceof SSLSocket) upgradeTLS((SSLSocket) ssl); return ssl; } }

然后我们只需要给我们的请求设置这个SSLSocketFactory就可以了,我们以okhttp为例,如下:

//定义一个信任所有证书的TrustManager final X509TrustManager trustAllCert = new X509TrustManager() { @Override public void checkClientTrusted(java.security.cert.X509Certificate[] chain, String authType) throws CertificateException { }@Override public void checkServerTrusted(java.security.cert.X509Certificate[] chain, String authType) throws CertificateException { }@Override public java.security.cert.X509Certificate[] getAcceptedIssuers() { return new java.security.cert.X509Certificate[]{}; } }; //设置OkHttpClient OkHttpClient client = new OkHttpClient.Builder().sslSocketFactory(new SSL(trustAllCert), trustAllCert).build();

设置之后,用低版本手机测试Https,现在可以测试成功了。