背景

Android 4.4 及以下，使用 OkHttp 发送 Https 请求，报以下错误：

    javax.net.ssl.SSLHandshakeException: javax.net.ssl.SSLProtocolException: SSL handshake aborted: ssl=0x6b712c90: Failure in SSL library, usually a protocol errorerror:14077410:SSL routines:SSL23_GET_SERVER_HELLO:sslv3 alert handshake failure (external/openssl/ssl/s23_clnt.c:741 0x68111cd4:0x00000000)at com.android.org.conscrypt.OpenSSLSocketImpl.startHandshake(OpenSSLSocketImpl.java:448)at okhttp3.internal.connection.RealConnection.connectTls(RealConnection.java:302)at okhttp3.internal.connection.RealConnection.establishProtocol(RealConnection.java:270)at okhttp3.internal.connection.RealConnection.connect(RealConnection.java:162)at okhttp3.internal.connection.StreamAllocation.findConnection(StreamAllocation.java:257)at okhttp3.internal.connection.StreamAllocation.findHealthyConnection(StreamAllocation.java:135)at okhttp3.internal.connection.StreamAllocation.newStream(StreamAllocation.java:114)at okhttp3.internal.connection.ConnectInterceptor.intercept(ConnectInterceptor.java:42)at okhttp3.internal.http.RealInterceptorChain.proceed(RealInterceptorChain.java:147)at okhttp3.internal.http.RealInterceptorChain.proceed(RealInterceptorChain.java:121)at okhttp3.internal.cache.CacheInterceptor.intercept(CacheInterceptor.java:93)at okhttp3.internal.http.RealInterceptorChain.proceed(RealInterceptorChain.java:147)at okhttp3.internal.http.RealInterceptorChain.proceed(RealInterceptorChain.java:121)at okhttp3.internal.http.BridgeInterceptor.intercept(BridgeInterceptor.java:93)at okhttp3.internal.http.RealInterceptorChain.proceed(RealInterceptorChain.java:147)at okhttp3.internal.http.RetryAndFollowUpInterceptor.intercept(RetryAndFollowUpInterceptor.java:126)at okhttp3.internal.http.RealInterceptorChain.proceed(RealInterceptorChain.java:147)at okhttp3.internal.http.RealInterceptorChain.proceed(RealInterceptorChain.java:121)at okhttp3.RealCall.getResponseWithInterceptorChain(RealCall.java:200)at okhttp3.RealCall$AsyncCall.execute(RealCall.java:147)at okhttp3.internal.NamedRunnable.run(NamedRunnable.java:32)at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1112)at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:587)at java.lang.Thread.run(Thread.java:841)Caused by: javax.net.ssl.SSLProtocolException: SSL handshake aborted: ssl=0x6b712c90: Failure in SSL library, usually a protocol errorerror:14077410:SSL routines:SSL23_GET_SERVER_HELLO:sslv3 alert handshake failure (external/openssl/ssl/s23_clnt.c:741 0x68111cd4:0x00000000)at com.android.org.conscrypt.NativeCrypto.SSL_do_handshake(Native Method)at com.android.org.conscrypt.OpenSSLSocketImpl.startHandshake(OpenSSLSocketImpl.java:405)... 23 more

一、确保OkHttp的Https配置正确

首先配制好 sslSocketFactory 和 hostnameVerifier：

import android.annotation.SuppressLint
import java.net.InetAddress
import java.net.Socket
import java.security.cert.CertificateException
import java.security.cert.X509Certificate
import javax.net.ssl.SSLContext
import javax.net.ssl.SSLSocket
import javax.net.ssl.SSLSocketFactory
import javax.net.ssl.TrustManager
import javax.net.ssl.X509TrustManagerclass MySSLSocketFactory(tm: TrustManager = TrustAllTrustManager()) : SSLSocketFactory() {var internalSSLSocketFactory: SSLSocketFactoryvar context: SSLContext = SSLContext.getInstance("TLSv1.1")init {context.init(null, arrayOf(tm), null)internalSSLSocketFactory = context.socketFactory}override fun getDefaultCipherSuites(): Array<String> {return internalSSLSocketFactory.defaultCipherSuites}override fun createSocket(s: Socket?, host: String?, port: Int, autoClose: Boolean): Socket {val sslSocket = context.socketFactory?.createSocket(s, host, port, autoClose) as SSLSocketsslSocket.enabledProtocols = arrayOf("TLSv1.2", "TLSv1.1")return sslSocket}override fun getSupportedCipherSuites(): Array<String> {return internalSSLSocketFactory.supportedCipherSuites}override fun createSocket(host: String?, port: Int): Socket {val sslSocket = context.socketFactory?.createSocket(host, port) as SSLSocketsslSocket.enabledProtocols = arrayOf("TLSv1.2", "TLSv1.1")return sslSocket}override fun createSocket(host: String?, port: Int, localHost: InetAddress?, localPort: Int): Socket {val sslSocket = context.socketFactory?.createSocket(host, port, localHost, localPort) as SSLSocketsslSocket.enabledProtocols = arrayOf("TLSv1.2", "TLSv1.1")return sslSocket}override fun createSocket(host: InetAddress?, port: Int): Socket {val sslSocket = context.socketFactory?.createSocket(host, port) as SSLSocketsslSocket.enabledProtocols = arrayOf("TLSv1.2", "TLSv1.1")return sslSocket}override fun createSocket(address: InetAddress?, port: Int, localAddress: InetAddress?, localPort: Int): Socket {val sslSocket = context.socketFactory?.createSocket(address, port, localAddress, localPort) as SSLSocketsslSocket.enabledProtocols = arrayOf("TLSv1.2", "TLSv1.1")return sslSocket}@SuppressLint("CustomX509TrustManager", "TrustAllX509TrustManager")class TrustAllTrustManager : X509TrustManager {@Throws(CertificateException::class)override fun checkClientTrusted(chain: Array<X509Certificate>, authType: String) {}@Throws(CertificateException::class)override fun checkServerTrusted(chain: Array<X509Certificate>, authType: String) {}override fun getAcceptedIssuers(): Array<X509Certificate> {return arrayOf()}}
}public class SSLSocketClient {//获取这个SSLSocketFactorypublic static SSLSocketFactory getSSLSocketFactory() {try {SSLContext sslContext = SSLContext.getInstance("SSL");sslContext.init(null, getTrustManager(), new SecureRandom());return sslContext.getSocketFactory();} catch (Exception e) {throw new RuntimeException(e);}}//获取TrustManagerprivate static TrustManager[] getTrustManager() {return new TrustManager[]{new X509TrustManager() {@Overridepublic void checkClientTrusted(X509Certificate[] chain, String authType) {}@Overridepublic void checkServerTrusted(X509Certificate[] chain, String authType) {}@Overridepublic X509Certificate[] getAcceptedIssuers() {return new X509Certificate[0];}}};}//获取HostnameVerifierpublic static HostnameVerifier getHostnameVerifier() {HostnameVerifier hostnameVerifier = new HostnameVerifier() {@Overridepublic boolean verify(String s, SSLSession sslSession) {return true;}};return hostnameVerifier;}
}

在OkHttp中使用：

    val tm = TrustAllTrustManager()val client = OkHttpClient.Builder().sslSocketFactory(MySSLSocketFactory(tm), tm).hostnameVerifier(SSLSocketClient.getHostnameVerifier()).build()val request = Request.Builder().url(url).build()client.newCall(request).enqueue(object : Callback {override fun onFailure(call: Call, e: IOException) {Log.w(TAG, "onFailure: ", e)onResult(Log.getStackTraceString(e))}override fun onResponse(call: Call, response: Response) {val result = response.body()?.string()onResult(result)}})

二、仍然报错的解决方案

如果通过以上的配置，仍然报 Failure in SSL library, usually a protocol error 的错，则有以下两种解决方案：

1. 降级OkHttp

将 OkHttp 降级到 3.9.0，即可正常请求。

2. 配置ConnectionSpec

在 OkHttpClient 创建的过程中，添加 ConnectionSpec 的配置，如下：

    // ConnectionSpec的配置val spec = ConnectionSpec.Builder(ConnectionSpec.COMPATIBLE_TLS).tlsVersions(TlsVersion.TLS_1_2, TlsVersion.TLS_1_1, TlsVersion.TLS_1_0).cipherSuites(CipherSuite.TLS_ECDHE_ECDSA_WITH_AES_128_GCM_SHA256,CipherSuite.TLS_ECDHE_ECDSA_WITH_CHACHA20_POLY1305_SHA256,CipherSuite.TLS_ECDHE_ECDSA_WITH_AES_128_CBC_SHA,CipherSuite.TLS_ECDHE_ECDSA_WITH_AES_256_CBC_SHA).build()val tm = TrustAllTrustManager()val client = OkHttpClient.Builder().connectionSpecs(Collections.singletonList(spec)).sslSocketFactory(MySSLSocketFactory(tm), tm).hostnameVerifier(SSLSocketClient.getHostnameVerifier()).build()val request = Request.Builder().url(url).build()client.newCall(request).enqueue(object : Callback {override fun onFailure(call: Call, e: IOException) {Log.w(TAG, "onFailure: ", e)onResult(Log.getStackTraceString(e))}override fun onResponse(call: Call, response: Response) {val result = response.body()?.string()onResult(result)}})