1 /*
2  * Copyright (c) 1997, 2013, Oracle and/or its affiliates. All rights reserved.
3  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
4  *
5  * This code is free software; you can redistribute it and/or modify it
6  * under the terms of the GNU General Public License version 2 only, as
7  * published by the Free Software Foundation.  Oracle designates this
8  * particular file as subject to the "Classpath" exception as provided
9  * by Oracle in the LICENSE file that accompanied this code.
10  *
11  * This code is distributed in the hope that it will be useful, but WITHOUT
12  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
13  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
14  * version 2 for more details (a copy is included in the LICENSE file that
15  * accompanied this code).
16  *
17  * You should have received a copy of the GNU General Public License version
18  * 2 along with this work; if not, write to the Free Software Foundation,
19  * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
20  *
21  * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
22  * or visit www.oracle.com if you need additional information or have any
23  * questions.
24  */
25 
26 package sun.security.util;
27 
28 import java.security.*;
29 import java.io.*;
30 import java.security.CodeSigner;
31 import java.util.*;
32 import java.util.jar.*;
33 
34 import java.util.Base64;
35 
36 import sun.security.jca.Providers;
37 
38 /**
39  * This class is used to verify each entry in a jar file with its
40  * manifest value.
41  */
42 
43 public class ManifestEntryVerifier {
44 
45     private static final Debug debug = Debug.getInstance("jar");
46 
47     /**
48      * Holder class to lazily load Sun provider. NOTE: if
49      * Providers.getSunProvider returned a cached provider, we could avoid the
50      * need for caching the provider with this holder class; we should try to
51      * revisit this in JDK 8.
52      */
53     private static class SunProviderHolder {
54         private static final Provider instance = Providers.getSunProvider();
55     }
56 
57     /** the created digest objects */
58     HashMap<String, MessageDigest> createdDigests;
59 
60     /** the digests in use for a given entry*/
61     ArrayList<MessageDigest> digests;
62 
63     /** the manifest hashes for the digests in use */
64     ArrayList<byte[]> manifestHashes;
65 
66     private String name = null;
67     private Manifest man;
68 
69     private boolean skip = true;
70 
71     private JarEntry entry;
72 
73     private CodeSigner[] signers = null;
74 
75     /**
76      * Create a new ManifestEntryVerifier object.
77      */
ManifestEntryVerifier(Manifest man)78     public ManifestEntryVerifier(Manifest man)
79     {
80         createdDigests = new HashMap<String, MessageDigest>(11);
81         digests = new ArrayList<MessageDigest>();
82         manifestHashes = new ArrayList<byte[]>();
83         this.man = man;
84     }
85 
86     /**
87      * Find the hashes in the
88      * manifest for this entry, save them, and set the MessageDigest
89      * objects to calculate the hashes on the fly. If name is
90      * null it signifies that update/verify should ignore this entry.
91      */
setEntry(String name, JarEntry entry)92     public void setEntry(String name, JarEntry entry)
93         throws IOException
94     {
95         digests.clear();
96         manifestHashes.clear();
97         this.name = name;
98         this.entry = entry;
99 
100         skip = true;
101         signers = null;
102 
103         if (man == null || name == null) {
104             return;
105         }
106 
107         /* get the headers from the manifest for this entry */
108         /* if there aren't any, we can't verify any digests for this entry */
109 
110         Attributes attr = man.getAttributes(name);
111         if (attr == null) {
112             // ugh. we should be able to remove this at some point.
113             // there are broken jars floating around with ./name and /name
114             // in the manifest, and "name" in the zip/jar file.
115             attr = man.getAttributes("./"+name);
116             if (attr == null) {
117                 attr = man.getAttributes("/"+name);
118                 if (attr == null)
119                     return;
120             }
121         }
122 
123         for (Map.Entry<Object,Object> se : attr.entrySet()) {
124             String key = se.getKey().toString();
125 
126             if (key.toUpperCase(Locale.ENGLISH).endsWith("-DIGEST")) {
127                 // 7 is length of "-Digest"
128                 String algorithm = key.substring(0, key.length()-7);
129 
130                 MessageDigest digest = createdDigests.get(algorithm);
131 
132                 if (digest == null) {
133                     try {
134 
135                         digest = MessageDigest.getInstance
136                                         (algorithm, SunProviderHolder.instance);
137                         createdDigests.put(algorithm, digest);
138                     } catch (NoSuchAlgorithmException nsae) {
139                         // ignore
140                     }
141                 }
142 
143                 if (digest != null) {
144                     skip = false;
145                     digest.reset();
146                     digests.add(digest);
147                     manifestHashes.add(
148                                 Base64.getMimeDecoder().decode((String)se.getValue()));
149                 }
150             }
151         }
152     }
153 
154     /**
155      * update the digests for the digests we are interested in
156      */
update(byte buffer)157     public void update(byte buffer) {
158         if (skip) return;
159 
160         for (int i=0; i < digests.size(); i++) {
161             digests.get(i).update(buffer);
162         }
163     }
164 
165     /**
166      * update the digests for the digests we are interested in
167      */
update(byte buffer[], int off, int len)168     public void update(byte buffer[], int off, int len) {
169         if (skip) return;
170 
171         for (int i=0; i < digests.size(); i++) {
172             digests.get(i).update(buffer, off, len);
173         }
174     }
175 
176     /**
177      * get the JarEntry for this object
178      */
getEntry()179     public JarEntry getEntry()
180     {
181         return entry;
182     }
183 
184     /**
185      * go through all the digests, calculating the final digest
186      * and comparing it to the one in the manifest. If this is
187      * the first time we have verified this object, remove its
188      * code signers from sigFileSigners and place in verifiedSigners.
189      *
190      *
191      */
verify(Hashtable<String, CodeSigner[]> verifiedSigners, Hashtable<String, CodeSigner[]> sigFileSigners)192     public CodeSigner[] verify(Hashtable<String, CodeSigner[]> verifiedSigners,
193                 Hashtable<String, CodeSigner[]> sigFileSigners)
194         throws JarException
195     {
196         if (skip) {
197             return null;
198         }
199 
200         if (signers != null)
201             return signers;
202 
203         for (int i=0; i < digests.size(); i++) {
204 
205             MessageDigest digest  = digests.get(i);
206             byte [] manHash = manifestHashes.get(i);
207             byte [] theHash = digest.digest();
208 
209             if (debug != null) {
210                 debug.println("Manifest Entry: " +
211                                    name + " digest=" + digest.getAlgorithm());
212                 debug.println("  manifest " + toHex(manHash));
213                 debug.println("  computed " + toHex(theHash));
214                 debug.println();
215             }
216 
217             if (!MessageDigest.isEqual(theHash, manHash))
218                 throw new SecurityException(digest.getAlgorithm()+
219                                             " digest error for "+name);
220         }
221 
222         // take it out of sigFileSigners and put it in verifiedSigners...
223         signers = sigFileSigners.remove(name);
224         if (signers != null) {
225             verifiedSigners.put(name, signers);
226         }
227         return signers;
228     }
229 
230     // for the toHex function
231     private static final char[] hexc =
232             {'0','1','2','3','4','5','6','7','8','9','a','b','c','d','e','f'};
233     /**
234      * convert a byte array to a hex string for debugging purposes
235      * @param data the binary data to be converted to a hex string
236      * @return an ASCII hex string
237      */
238 
toHex(byte[] data)239     static String toHex(byte[] data) {
240 
241         StringBuffer sb = new StringBuffer(data.length*2);
242 
243         for (int i=0; i<data.length; i++) {
244             sb.append(hexc[(data[i] >>4) & 0x0f]);
245             sb.append(hexc[data[i] & 0x0f]);
246         }
247         return sb.toString();
248     }
249 
250 }
251