1/*
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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
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19 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
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21 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
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24 */
25
26package sun.security.validator;
27
28import java.util.*;
29
30import java.security.AlgorithmConstraints;
31import java.security.KeyStore;
32import java.security.cert.*;
33
34/**
35 * Validator abstract base class. Concrete classes are instantiated by calling
36 * one of the getInstance() methods. All methods defined in this class
37 * must be safe for concurrent use by multiple threads.<p>
38 *
39 * The model is that a Validator instance is created specifying validation
40 * settings, such as trust anchors or PKIX parameters. Then one or more
41 * paths are validated using those parameters. In some cases, additional
42 * information can be provided per path validation. This is independent of
43 * the validation parameters and currently only used for TLS server validation.
44 * <p>
45 * Path validation is performed by calling one of the validate() methods. It
46 * specifies a suggested path to be used for validation if available, or only
47 * the end entity certificate otherwise. Optionally additional certificates can
48 * be specified that the caller believes could be helpful. Implementations are
49 * free to make use of this information or validate the path using other means.
50 * validate() also checks that the end entity certificate is suitable for the
51 * intended purpose as described below.
52 *
53 * <p>There are two orthogonal parameters to select the Validator
54 * implementation: type and variant. Type selects the validation algorithm.
55 * Currently supported are TYPE_SIMPLE and TYPE_PKIX. See SimpleValidator and
56 * PKIXValidator for details.
57 * <p>
58 * Variant controls additional extension checks. Currently supported are
59 * five variants:
60 * <ul>
61 * <li>VAR_GENERIC (no additional checks),
62 * <li>VAR_TLS_CLIENT (TLS client specific checks)
63 * <li>VAR_TLS_SERVER (TLS server specific checks), and
64 * <li>VAR_CODE_SIGNING (code signing specific checks).
65 * <li>VAR_JCE_SIGNING (JCE code signing specific checks).
66 * <li>VAR_TSA_SERVER (TSA server specific checks).
67 * <li>VAR_PLUGIN_CODE_SIGNING (Plugin/WebStart code signing specific checks).
68 * </ul>
69 * See EndEntityChecker for more information.
70 * <p>
71 * Examples:
72 * <pre>
73 *   // instantiate validator specifying type, variant, and trust anchors
74 *   Validator validator = Validator.getInstance(Validator.TYPE_PKIX,
75 *                                               Validator.VAR_TLS_CLIENT,
76 *                                               trustedCerts);
77 *   // validate one or more chains using the validator
78 *   validator.validate(chain); // throws CertificateException if failed
79 * </pre>
80 *
81 * @see SimpleValidator
82 * @see PKIXValidator
83 * @see EndEntityChecker
84 *
85 * @author Andreas Sterbenz
86 */
87public abstract class Validator {
88
89    final static X509Certificate[] CHAIN0 = {};
90
91    /**
92     * Constant for a validator of type Simple.
93     * @see #getInstance
94     */
95    public final static String TYPE_SIMPLE = "Simple";
96
97    /**
98     * Constant for a validator of type PKIX.
99     * @see #getInstance
100     */
101    public final static String TYPE_PKIX = "PKIX";
102
103    /**
104     * Constant for a Generic variant of a validator.
105     * @see #getInstance
106     */
107    public final static String VAR_GENERIC = "generic";
108
109    /**
110     * Constant for a Code Signing variant of a validator.
111     * @see #getInstance
112     */
113    public final static String VAR_CODE_SIGNING = "code signing";
114
115    /**
116     * Constant for a JCE Code Signing variant of a validator.
117     * @see #getInstance
118     */
119    public final static String VAR_JCE_SIGNING = "jce signing";
120
121    /**
122     * Constant for a TLS Client variant of a validator.
123     * @see #getInstance
124     */
125    public final static String VAR_TLS_CLIENT = "tls client";
126
127    /**
128     * Constant for a TLS Server variant of a validator.
129     * @see #getInstance
130     */
131    public final static String VAR_TLS_SERVER = "tls server";
132
133    /**
134     * Constant for a TSA Server variant of a validator.
135     * @see #getInstance
136     */
137    public final static String VAR_TSA_SERVER = "tsa server";
138
139    /**
140     * Constant for a Code Signing variant of a validator for use by
141     * the J2SE Plugin/WebStart code.
142     * @see #getInstance
143     */
144    public final static String VAR_PLUGIN_CODE_SIGNING = "plugin code signing";
145
146    final EndEntityChecker endEntityChecker;
147    final String variant;
148
149    /**
150     * @deprecated
151     * @see #setValidationDate
152     */
153    @Deprecated
154    volatile Date validationDate;
155
156    Validator(String type, String variant) {
157        this.variant = variant;
158        endEntityChecker = EndEntityChecker.getInstance(type, variant);
159    }
160
161    /**
162     * Get a new Validator instance using the trusted certificates from the
163     * specified KeyStore as trust anchors.
164     */
165    public static Validator getInstance(String type, String variant,
166            KeyStore ks) {
167        return getInstance(type, variant, KeyStores.getTrustedCerts(ks));
168    }
169
170    /**
171     * Get a new Validator instance using the Set of X509Certificates as trust
172     * anchors.
173     */
174    public static Validator getInstance(String type, String variant,
175            Collection<X509Certificate> trustedCerts) {
176        if (type.equals(TYPE_SIMPLE)) {
177            return new SimpleValidator(variant, trustedCerts);
178        } else if (type.equals(TYPE_PKIX)) {
179            return new PKIXValidator(variant, trustedCerts);
180        } else {
181            throw new IllegalArgumentException
182                ("Unknown validator type: " + type);
183        }
184    }
185
186    /**
187     * Get a new Validator instance using the provided PKIXBuilderParameters.
188     * This method can only be used with the PKIX validator.
189     */
190    public static Validator getInstance(String type, String variant,
191            PKIXBuilderParameters params) {
192        if (type.equals(TYPE_PKIX) == false) {
193            throw new IllegalArgumentException
194                ("getInstance(PKIXBuilderParameters) can only be used "
195                + "with PKIX validator");
196        }
197        return new PKIXValidator(variant, params);
198    }
199
200    /**
201     * Validate the given certificate chain.
202     */
203    public final X509Certificate[] validate(X509Certificate[] chain)
204            throws CertificateException {
205        return validate(chain, null, null);
206    }
207
208    /**
209     * Validate the given certificate chain. If otherCerts is non-null, it is
210     * a Collection of additional X509Certificates that could be helpful for
211     * path building.
212     */
213    public final X509Certificate[] validate(X509Certificate[] chain,
214        Collection<X509Certificate> otherCerts) throws CertificateException {
215        return validate(chain, otherCerts, null);
216    }
217
218    /**
219     * Validate the given certificate chain. If otherCerts is non-null, it is
220     * a Collection of additional X509Certificates that could be helpful for
221     * path building.
222     * <p>
223     * Parameter is an additional parameter with variant specific meaning.
224     * Currently, it is only defined for TLS_SERVER variant validators, where
225     * it must be non null and the name of the TLS key exchange algorithm being
226     * used (see JSSE X509TrustManager specification). In the future, it
227     * could be used to pass in a PKCS#7 object for code signing to check time
228     * stamps.
229     * <p>
230     * @return a non-empty chain that was used to validate the path. The
231     * end entity cert is at index 0, the trust anchor at index n-1.
232     */
233    public final X509Certificate[] validate(X509Certificate[] chain,
234            Collection<X509Certificate> otherCerts, Object parameter)
235            throws CertificateException {
236        return validate(chain, otherCerts, null, parameter);
237    }
238
239    /**
240     * Validate the given certificate chain.
241     *
242     * @param chain the target certificate chain
243     * @param otherCerts a Collection of additional X509Certificates that
244     *        could be helpful for path building (or null)
245     * @param constraints algorithm constraints for certification path
246     *        processing
247     * @param parameter an additional parameter with variant specific meaning.
248     *        Currently, it is only defined for TLS_SERVER variant validators,
249     *        where it must be non null and the name of the TLS key exchange
250     *        algorithm being used (see JSSE X509TrustManager specification).
251     *        In the future, it could be used to pass in a PKCS#7 object for
252     *        code signing to check time stamps.
253     * @return a non-empty chain that was used to validate the path. The
254     *        end entity cert is at index 0, the trust anchor at index n-1.
255     */
256    public final X509Certificate[] validate(X509Certificate[] chain,
257                Collection<X509Certificate> otherCerts,
258                AlgorithmConstraints constraints,
259                Object parameter) throws CertificateException {
260        chain = engineValidate(chain, otherCerts, constraints, parameter);
261
262        // omit EE extension check if EE cert is also trust anchor
263        if (chain.length > 1) {
264            endEntityChecker.check(chain[0], parameter);
265        }
266
267        return chain;
268    }
269
270    abstract X509Certificate[] engineValidate(X509Certificate[] chain,
271                Collection<X509Certificate> otherCerts,
272                AlgorithmConstraints constraints,
273                Object parameter) throws CertificateException;
274
275    /**
276     * Returns an immutable Collection of the X509Certificates this instance
277     * uses as trust anchors.
278     */
279    public abstract Collection<X509Certificate> getTrustedCertificates();
280
281    /**
282     * Set the date to be used for subsequent validations. NOTE that
283     * this is not a supported API, it is provided to simplify
284     * writing tests only.
285     *
286     * @deprecated
287     */
288    @Deprecated
289    public void setValidationDate(Date validationDate) {
290        this.validationDate = validationDate;
291    }
292
293}
294