1 /*
2 * Copyright 1997-2006 Sun Microsystems, Inc. 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. Sun designates this
8 * particular file as subject to the "Classpath" exception as provided
9 * by Sun 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 Sun Microsystems, Inc., 4150 Network Circle, Santa Clara,
22 * CA 95054 USA or visit www.sun.com if you need additional information or
23 * have any questions.
24 */
25
26 package java.security.cert;
27
28 import java.util.Arrays;
29
30 import java.security.PublicKey;
31 import java.security.NoSuchAlgorithmException;
32 import java.security.NoSuchProviderException;
33 import java.security.InvalidKeyException;
34 import java.security.SignatureException;
35
36 import sun.security.x509.X509CertImpl;
37
38 /**
39 * <p>Abstract class for managing a variety of identity certificates.
40 * An identity certificate is a binding of a principal to a public key which
41 * is vouched for by another principal. (A principal represents
42 * an entity such as an individual user, a group, or a corporation.)
43 *<p>
44 * This class is an abstraction for certificates that have different
45 * formats but important common uses. For example, different types of
46 * certificates, such as X.509 and PGP, share general certificate
47 * functionality (like encoding and verifying) and
48 * some types of information (like a public key).
49 * <p>
50 * X.509, PGP, and SDSI certificates can all be implemented by
51 * subclassing the Certificate class, even though they contain different
52 * sets of information, and they store and retrieve the information in
53 * different ways.
54 *
55 * @see X509Certificate
56 * @see CertificateFactory
57 *
58 * @author Hemma Prafullchandra
59 */
60
61 public abstract class Certificate implements java.io.Serializable {
62
63 private static final long serialVersionUID = -3585440601605666277L;
64
65 // the certificate type
66 private final String type;
67
68 /**
69 * Creates a certificate of the specified type.
70 *
71 * @param type the standard name of the certificate type.
72 * See Appendix A in the <a href=
73 * "../../../../technotes/guides/security/crypto/CryptoSpec.html#AppA">
74 * Java Cryptography Architecture API Specification & Reference </a>
75 * for information about standard certificate types.
76 */
77 protected Certificate(String type) {
78 this.type = type;
79 }
80
81 /**
82 * Returns the type of this certificate.
83 *
84 * @return the type of this certificate.
85 */
86 public final String getType() {
87 return this.type;
88 }
89
90 /**
91 * Compares this certificate for equality with the specified
92 * object. If the <code>other</code> object is an
93 * <code>instanceof</code> <code>Certificate</code>, then
94 * its encoded form is retrieved and compared with the
95 * encoded form of this certificate.
96 *
97 * @param other the object to test for equality with this certificate.
98 * @return true iff the encoded forms of the two certificates
99 * match, false otherwise.
100 */
101 public boolean equals(Object other) {
102 if (this == other) {
103 return true;
104 }
105 if (!(other instanceof Certificate)) {
106 return false;
107 }
108 try {
109 byte[] thisCert = X509CertImpl.getEncodedInternal(this);
110 byte[] otherCert = X509CertImpl.getEncodedInternal((Certificate)other);
111
112 return Arrays.equals(thisCert, otherCert);
113 } catch (CertificateException e) {
114 return false;
115 }
116 }
117
118 /**
119 * Returns a hashcode value for this certificate from its
120 * encoded form.
121 *
122 * @return the hashcode value.
123 */
124 public int hashCode() {
125 int retval = 0;
126 try {
127 byte[] certData = X509CertImpl.getEncodedInternal(this);
128 for (int i = 1; i < certData.length; i++) {
129 retval += certData[i] * i;
130 }
131 return retval;
132 } catch (CertificateException e) {
133 return retval;
134 }
135 }
136
137 /**
138 * Returns the encoded form of this certificate. It is
139 * assumed that each certificate type would have only a single
140 * form of encoding; for example, X.509 certificates would
141 * be encoded as ASN.1 DER.
142 *
143 * @return the encoded form of this certificate
144 *
145 * @exception CertificateEncodingException if an encoding error occurs.
146 */
147 public abstract byte[] getEncoded()
148 throws CertificateEncodingException;
149
150 /**
151 * Verifies that this certificate was signed using the
152 * private key that corresponds to the specified public key.
153 *
154 * @param key the PublicKey used to carry out the verification.
155 *
156 * @exception NoSuchAlgorithmException on unsupported signature
157 * algorithms.
158 * @exception InvalidKeyException on incorrect key.
159 * @exception NoSuchProviderException if there's no default provider.
160 * @exception SignatureException on signature errors.
161 * @exception CertificateException on encoding errors.
162 */
163 public abstract void verify(PublicKey key)
164 throws CertificateException, NoSuchAlgorithmException,
165 InvalidKeyException, NoSuchProviderException,
166 SignatureException;
167
168 /**
169 * Verifies that this certificate was signed using the
170 * private key that corresponds to the specified public key.
171 * This method uses the signature verification engine
172 * supplied by the specified provider.
173 *
174 * @param key the PublicKey used to carry out the verification.
175 * @param sigProvider the name of the signature provider.
176 *
177 * @exception NoSuchAlgorithmException on unsupported signature
178 * algorithms.
179 * @exception InvalidKeyException on incorrect key.
180 * @exception NoSuchProviderException on incorrect provider.
181 * @exception SignatureException on signature errors.
182 * @exception CertificateException on encoding errors.
183 */
184 public abstract void verify(PublicKey key, String sigProvider)
185 throws CertificateException, NoSuchAlgorithmException,
186 InvalidKeyException, NoSuchProviderException,
187 SignatureException;
188
189 /**
190 * Returns a string representation of this certificate.
191 *
192 * @return a string representation of this certificate.
193 */
194 public abstract String toString();
195
196 /**
197 * Gets the public key from this certificate.
198 *
199 * @return the public key.
200 */
201 public abstract PublicKey getPublicKey();
202
203 /**
204 * Alternate Certificate class for serialization.
205 * @since 1.3
206 */
207 protected static class CertificateRep implements java.io.Serializable {
208
209 private static final long serialVersionUID = -8563758940495660020L;
210
211 private String type;
212 private byte[] data;
213
214 /**
215 * Construct the alternate Certificate class with the Certificate
216 * type and Certificate encoding bytes.
217 *
218 * <p>
219 *
220 * @param type the standard name of the Certificate type. <p>
221 *
222 * @param data the Certificate data.
223 */
224 protected CertificateRep(String type, byte[] data) {
225 this.type = type;
226 this.data = data;
227 }
228
229 /**
230 * Resolve the Certificate Object.
231 *
232 * <p>
233 *
234 * @return the resolved Certificate Object
235 *
236 * @throws java.io.ObjectStreamException if the Certificate
237 * could not be resolved
238 */
239 protected Object readResolve() throws java.io.ObjectStreamException {
240 try {
241 CertificateFactory cf = CertificateFactory.getInstance(type);
242 return cf.generateCertificate
243 (new java.io.ByteArrayInputStream(data));
244 } catch (CertificateException e) {
245 throw new java.io.NotSerializableException
246 ("java.security.cert.Certificate: " +
247 type +
248 ": " +
249 e.getMessage());
250 }
251 }
252 }
253
254 /**
255 * Replace the Certificate to be serialized.
256 *
257 * @return the alternate Certificate object to be serialized
258 *
259 * @throws java.io.ObjectStreamException if a new object representing
260 * this Certificate could not be created
261 * @since 1.3
262 */
263 protected Object writeReplace() throws java.io.ObjectStreamException {
264 try {
265 return new CertificateRep(type, getEncoded());
266 } catch (CertificateException e) {
267 throw new java.io.NotSerializableException
268 ("java.security.cert.Certificate: " +
269 type +
270 ": " +
271 e.getMessage());
272 }
273 }
274 }
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