1 /*
2  * Copyright (C) 2010 The Android Open Source Project
3  *
4  * Licensed under the Apache License, Version 2.0 (the "License");
5  * you may not use this file except in compliance with the License.
6  * You may obtain a copy of the License at
7  *
8  *      http://www.apache.org/licenses/LICENSE-2.0
9  *
10  * Unless required by applicable law or agreed to in writing, software
11  * distributed under the License is distributed on an "AS IS" BASIS,
12  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13  * See the License for the specific language governing permissions and
14  * limitations under the License.
15  */
16 
17 package android.net;
18 
19 import android.content.Context;
20 import android.util.Log;
21 
22 import com.android.org.conscrypt.ClientSessionContext;
23 import com.android.org.conscrypt.FileClientSessionCache;
24 import com.android.org.conscrypt.SSLClientSessionCache;
25 
26 import java.io.File;
27 import java.io.IOException;
28 
29 import javax.net.ssl.SSLContext;
30 import javax.net.ssl.SSLSessionContext;
31 
32 /**
33  * File-based cache of established SSL sessions.  When re-establishing a
34  * connection to the same server, using an SSL session cache can save some time,
35  * power, and bandwidth by skipping directly to an encrypted stream.
36  * This is a persistent cache which can span executions of the application.
37  *
38  * @see SSLCertificateSocketFactory
39  */
40 public final class SSLSessionCache {
41     private static final String TAG = "SSLSessionCache";
42     /* package */ final SSLClientSessionCache mSessionCache;
43 
44     /**
45      * Installs a {@link SSLSessionCache} on a {@link SSLContext}. The cache will
46      * be used on all socket factories created by this context (including factories
47      * created before this call).
48      *
49      * @param cache the cache instance to install, or {@code null} to uninstall any
50      *         existing cache.
51      * @param context the context to install it on.
52      * @throws IllegalArgumentException if the context does not support a session
53      *         cache.
54      *
55      * @hide candidate for public API
56      */
install(SSLSessionCache cache, SSLContext context)57     public static void install(SSLSessionCache cache, SSLContext context) {
58         SSLSessionContext clientContext = context.getClientSessionContext();
59         if (clientContext instanceof ClientSessionContext) {
60             ((ClientSessionContext) clientContext).setPersistentCache(
61                     cache == null ? null : cache.mSessionCache);
62         } else {
63             throw new IllegalArgumentException("Incompatible SSLContext: " + context);
64         }
65     }
66 
67     /**
68      * NOTE: This needs to be Object (and not SSLClientSessionCache) because apps
69      * that build directly against the framework (and not the SDK) might not declare
70      * a dependency on conscrypt. Javac will then has fail while resolving constructors.
71      *
72      * @hide For unit test use only
73      */
SSLSessionCache(Object cache)74     public SSLSessionCache(Object cache) {
75         mSessionCache = (SSLClientSessionCache) cache;
76     }
77 
78     /**
79      * Create a session cache using the specified directory.
80      * Individual session entries will be files within the directory.
81      * Multiple instances for the same directory share data internally.
82      *
83      * @param dir to store session files in (created if necessary)
84      * @throws IOException if the cache can't be opened
85      */
SSLSessionCache(File dir)86     public SSLSessionCache(File dir) throws IOException {
87         mSessionCache = FileClientSessionCache.usingDirectory(dir);
88     }
89 
90     /**
91      * Create a session cache at the default location for this app.
92      * Multiple instances share data internally.
93      *
94      * @param context for the application
95      */
SSLSessionCache(Context context)96     public SSLSessionCache(Context context) {
97         File dir = context.getDir("sslcache", Context.MODE_PRIVATE);
98         SSLClientSessionCache cache = null;
99         try {
100             cache = FileClientSessionCache.usingDirectory(dir);
101         } catch (IOException e) {
102             Log.w(TAG, "Unable to create SSL session cache in " + dir, e);
103         }
104         mSessionCache = cache;
105     }
106 }
107