J. Duke | 319a3b9 | 2007-12-01 00:00:00 +0000 | [diff] [blame^] | 1 | /* |
| 2 | * Copyright 2000-2003 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.security.KeyStore; |
| 29 | import java.security.KeyStoreException; |
| 30 | import java.security.InvalidAlgorithmParameterException; |
| 31 | import java.security.InvalidParameterException; |
| 32 | import java.util.Set; |
| 33 | |
| 34 | /** |
| 35 | * Parameters used as input for the PKIX <code>CertPathBuilder</code> |
| 36 | * algorithm. |
| 37 | * <p> |
| 38 | * A PKIX <code>CertPathBuilder</code> uses these parameters to {@link |
| 39 | * CertPathBuilder#build build} a <code>CertPath</code> which has been |
| 40 | * validated according to the PKIX certification path validation algorithm. |
| 41 | * |
| 42 | * <p>To instantiate a <code>PKIXBuilderParameters</code> object, an |
| 43 | * application must specify one or more <i>most-trusted CAs</i> as defined by |
| 44 | * the PKIX certification path validation algorithm. The most-trusted CA |
| 45 | * can be specified using one of two constructors. An application |
| 46 | * can call {@link #PKIXBuilderParameters(Set, CertSelector) |
| 47 | * PKIXBuilderParameters(Set, CertSelector)}, specifying a |
| 48 | * <code>Set</code> of <code>TrustAnchor</code> objects, each of which |
| 49 | * identifies a most-trusted CA. Alternatively, an application can call |
| 50 | * {@link #PKIXBuilderParameters(KeyStore, CertSelector) |
| 51 | * PKIXBuilderParameters(KeyStore, CertSelector)}, specifying a |
| 52 | * <code>KeyStore</code> instance containing trusted certificate entries, each |
| 53 | * of which will be considered as a most-trusted CA. |
| 54 | * |
| 55 | * <p>In addition, an application must specify constraints on the target |
| 56 | * certificate that the <code>CertPathBuilder</code> will attempt |
| 57 | * to build a path to. The constraints are specified as a |
| 58 | * <code>CertSelector</code> object. These constraints should provide the |
| 59 | * <code>CertPathBuilder</code> with enough search criteria to find the target |
| 60 | * certificate. Minimal criteria for an <code>X509Certificate</code> usually |
| 61 | * include the subject name and/or one or more subject alternative names. |
| 62 | * If enough criteria is not specified, the <code>CertPathBuilder</code> |
| 63 | * may throw a <code>CertPathBuilderException</code>. |
| 64 | * <p> |
| 65 | * <b>Concurrent Access</b> |
| 66 | * <p> |
| 67 | * Unless otherwise specified, the methods defined in this class are not |
| 68 | * thread-safe. Multiple threads that need to access a single |
| 69 | * object concurrently should synchronize amongst themselves and |
| 70 | * provide the necessary locking. Multiple threads each manipulating |
| 71 | * separate objects need not synchronize. |
| 72 | * |
| 73 | * @see CertPathBuilder |
| 74 | * |
| 75 | * @since 1.4 |
| 76 | * @author Sean Mullan |
| 77 | */ |
| 78 | public class PKIXBuilderParameters extends PKIXParameters { |
| 79 | |
| 80 | private int maxPathLength = 5; |
| 81 | |
| 82 | /** |
| 83 | * Creates an instance of <code>PKIXBuilderParameters</code> with |
| 84 | * the specified <code>Set</code> of most-trusted CAs. |
| 85 | * Each element of the set is a {@link TrustAnchor TrustAnchor}. |
| 86 | * |
| 87 | * <p>Note that the <code>Set</code> is copied to protect against |
| 88 | * subsequent modifications. |
| 89 | * |
| 90 | * @param trustAnchors a <code>Set</code> of <code>TrustAnchor</code>s |
| 91 | * @param targetConstraints a <code>CertSelector</code> specifying the |
| 92 | * constraints on the target certificate |
| 93 | * @throws InvalidAlgorithmParameterException if <code>trustAnchors</code> |
| 94 | * is empty <code>(trustAnchors.isEmpty() == true)</code> |
| 95 | * @throws NullPointerException if <code>trustAnchors</code> is |
| 96 | * <code>null</code> |
| 97 | * @throws ClassCastException if any of the elements of |
| 98 | * <code>trustAnchors</code> are not of type |
| 99 | * <code>java.security.cert.TrustAnchor</code> |
| 100 | */ |
| 101 | public PKIXBuilderParameters(Set<TrustAnchor> trustAnchors, CertSelector |
| 102 | targetConstraints) throws InvalidAlgorithmParameterException |
| 103 | { |
| 104 | super(trustAnchors); |
| 105 | setTargetCertConstraints(targetConstraints); |
| 106 | } |
| 107 | |
| 108 | /** |
| 109 | * Creates an instance of <code>PKIXBuilderParameters</code> that |
| 110 | * populates the set of most-trusted CAs from the trusted |
| 111 | * certificate entries contained in the specified <code>KeyStore</code>. |
| 112 | * Only keystore entries that contain trusted <code>X509Certificate</code>s |
| 113 | * are considered; all other certificate types are ignored. |
| 114 | * |
| 115 | * @param keystore a <code>KeyStore</code> from which the set of |
| 116 | * most-trusted CAs will be populated |
| 117 | * @param targetConstraints a <code>CertSelector</code> specifying the |
| 118 | * constraints on the target certificate |
| 119 | * @throws KeyStoreException if <code>keystore</code> has not been |
| 120 | * initialized |
| 121 | * @throws InvalidAlgorithmParameterException if <code>keystore</code> does |
| 122 | * not contain at least one trusted certificate entry |
| 123 | * @throws NullPointerException if <code>keystore</code> is |
| 124 | * <code>null</code> |
| 125 | */ |
| 126 | public PKIXBuilderParameters(KeyStore keystore, |
| 127 | CertSelector targetConstraints) |
| 128 | throws KeyStoreException, InvalidAlgorithmParameterException |
| 129 | { |
| 130 | super(keystore); |
| 131 | setTargetCertConstraints(targetConstraints); |
| 132 | } |
| 133 | |
| 134 | /** |
| 135 | * Sets the value of the maximum number of non-self-issued intermediate |
| 136 | * certificates that may exist in a certification path. A certificate |
| 137 | * is self-issued if the DNs that appear in the subject and issuer |
| 138 | * fields are identical and are not empty. Note that the last certificate |
| 139 | * in a certification path is not an intermediate certificate, and is not |
| 140 | * included in this limit. Usually the last certificate is an end entity |
| 141 | * certificate, but it can be a CA certificate. A PKIX |
| 142 | * <code>CertPathBuilder</code> instance must not build |
| 143 | * paths longer than the length specified. |
| 144 | * |
| 145 | * <p> A value of 0 implies that the path can only contain |
| 146 | * a single certificate. A value of -1 implies that the |
| 147 | * path length is unconstrained (i.e. there is no maximum). |
| 148 | * The default maximum path length, if not specified, is 5. |
| 149 | * Setting a value less than -1 will cause an exception to be thrown. |
| 150 | * |
| 151 | * <p> If any of the CA certificates contain the |
| 152 | * <code>BasicConstraintsExtension</code>, the value of the |
| 153 | * <code>pathLenConstraint</code> field of the extension overrides |
| 154 | * the maximum path length parameter whenever the result is a |
| 155 | * certification path of smaller length. |
| 156 | * |
| 157 | * @param maxPathLength the maximum number of non-self-issued intermediate |
| 158 | * certificates that may exist in a certification path |
| 159 | * @throws InvalidParameterException if <code>maxPathLength</code> is set |
| 160 | * to a value less than -1 |
| 161 | * |
| 162 | * @see #getMaxPathLength |
| 163 | */ |
| 164 | public void setMaxPathLength(int maxPathLength) { |
| 165 | if (maxPathLength < -1) { |
| 166 | throw new InvalidParameterException("the maximum path " |
| 167 | + "length parameter can not be less than -1"); |
| 168 | } |
| 169 | this.maxPathLength = maxPathLength; |
| 170 | } |
| 171 | |
| 172 | /** |
| 173 | * Returns the value of the maximum number of intermediate non-self-issued |
| 174 | * certificates that may exist in a certification path. See |
| 175 | * the {@link #setMaxPathLength} method for more details. |
| 176 | * |
| 177 | * @return the maximum number of non-self-issued intermediate certificates |
| 178 | * that may exist in a certification path, or -1 if there is no limit |
| 179 | * |
| 180 | * @see #setMaxPathLength |
| 181 | */ |
| 182 | public int getMaxPathLength() { |
| 183 | return maxPathLength; |
| 184 | } |
| 185 | |
| 186 | /** |
| 187 | * Returns a formatted string describing the parameters. |
| 188 | * |
| 189 | * @return a formatted string describing the parameters |
| 190 | */ |
| 191 | public String toString() { |
| 192 | StringBuffer sb = new StringBuffer(); |
| 193 | sb.append("[\n"); |
| 194 | sb.append(super.toString()); |
| 195 | sb.append(" Maximum Path Length: " + maxPathLength + "\n"); |
| 196 | sb.append("]\n"); |
| 197 | return sb.toString(); |
| 198 | } |
| 199 | } |