1 /*
2  * Copyright (C) 2012 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 org.bouncycastle.crypto.digests;
18 
19 import org.bouncycastle.crypto.Digest;
20 
21 /**
22  * Level of indirection to let us select OpenSSLDigest implementations
23  * for libcore but fallback to BouncyCastle ones on the RI.
24  */
25 public final class AndroidDigestFactory {
26     private static final String OpenSSLFactoryClassName
27             = AndroidDigestFactory.class.getName() + "OpenSSL";
28     private static final String BouncyCastleFactoryClassName
29             = AndroidDigestFactory.class.getName() + "BouncyCastle";
30 
31     private static final AndroidDigestFactoryInterface FACTORY;
32     static {
33         Class factoryImplementationClass;
34         try {
35             factoryImplementationClass = Class.forName(OpenSSLFactoryClassName);
36             // Double check for NativeCrypto in case we are running on RI for testing
37             Class.forName("com.android.org.conscrypt.NativeCrypto");
38         } catch (ClassNotFoundException e1) {
39             try {
40                 factoryImplementationClass = Class.forName(BouncyCastleFactoryClassName);
41             } catch (ClassNotFoundException e2) {
42                 AssertionError e = new AssertionError("Failed to load "
43                                          + "AndroidDigestFactoryInterface "
44                                          + "implementation. Looked for "
45                                          + OpenSSLFactoryClassName + " and "
46                                          + BouncyCastleFactoryClassName);
47                 e.initCause(e1);
48                 throw e;
49             }
50         }
51         if (!AndroidDigestFactoryInterface.class.isAssignableFrom(factoryImplementationClass)) {
52             throw new AssertionError(factoryImplementationClass
53                                      + "does not implement AndroidDigestFactoryInterface");
54         }
55         try {
56             FACTORY = (AndroidDigestFactoryInterface) factoryImplementationClass.newInstance();
57         } catch (InstantiationException e) {
58             throw new AssertionError(e);
59         } catch (IllegalAccessException e) {
60             throw new AssertionError(e);
61         }
62     }
63 
getMD5()64     public static Digest getMD5() {
65         return FACTORY.getMD5();
66     }
67 
getSHA1()68     public static Digest getSHA1() {
69         return FACTORY.getSHA1();
70     }
71 
getSHA224()72     public static Digest getSHA224() {
73         return FACTORY.getSHA224();
74     }
75 
getSHA256()76     public static Digest getSHA256() {
77         return FACTORY.getSHA256();
78     }
79 
getSHA384()80     public static Digest getSHA384() {
81         return FACTORY.getSHA384();
82     }
83 
getSHA512()84     public static Digest getSHA512() {
85         return FACTORY.getSHA512();
86     }
87 }
88