1 /* 2 * Licensed to the Apache Software Foundation (ASF) under one or more 3 * contributor license agreements. See the NOTICE file distributed with 4 * this work for additional information regarding copyright ownership. 5 * The ASF licenses this file to You under the Apache License, Version 2.0 6 * (the "License"); you may not use this file except in compliance with 7 * the License. You may obtain a copy of the License at 8 * 9 * http://www.apache.org/licenses/LICENSE-2.0 10 * 11 * Unless required by applicable law or agreed to in writing, software 12 * distributed under the License is distributed on an "AS IS" BASIS, 13 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 14 * See the License for the specific language governing permissions and 15 * limitations under the License. 16 */ 17 18 package javax.crypto.spec; 19 20 import java.security.spec.AlgorithmParameterSpec; 21 import java.util.Arrays; 22 23 /** 24 * The algorithm parameter specification for the <a 25 * href="http://www.ietf.org/rfc/rfc2040.txt">RC5</a> algorithm. 26 */ 27 public class RC5ParameterSpec implements AlgorithmParameterSpec { 28 29 private final int version; 30 private final int rounds; 31 private final int wordSize; 32 private final byte[] iv; 33 34 /** 35 * Creates a new <code>RC5ParameterSpec</code> instance with the specified 36 * version, round count an word size (in bits). 37 * 38 * @param version 39 * the version. 40 * @param rounds 41 * the round count. 42 * @param wordSize 43 * the word size (in bits). 44 */ 45 public RC5ParameterSpec(int version, int rounds, int wordSize) { 46 this.version = version; 47 this.rounds = rounds; 48 this.wordSize = wordSize; 49 this.iv = null; 50 } 51 52 /** 53 * Creates a new <code>RC5ParameterSpec</code> instance with the specified 54 * version, round count, word size (in bits) and an <i>initialization 55 * vector</i>. 56 * <p> 57 * The size of the <i>initialization vector</i> must be at least 58 * <code>2 * (wordSize / 8)</code> bytes which are copied to protect them 59 * against modification. 60 * 61 * @param version 62 * the version. 63 * @param rounds 64 * the round count. 65 * @param wordSize 66 * the word size (in bits). 67 * @param iv 68 * the initialization vector. 69 * @throws IllegalArgumentException 70 * if the initialization vector is null or shorter than <code>2 71 * * (wordSize / 8)</code>. 72 */ 73 public RC5ParameterSpec(int version, int rounds, int wordSize, byte[] iv) { 74 if (iv == null) { 75 throw new IllegalArgumentException("iv == null"); 76 } 77 if (iv.length < 2 * (wordSize / 8)) { 78 throw new IllegalArgumentException("iv.length < 2 * (wordSize / 8)"); 79 } 80 this.version = version; 81 this.rounds = rounds; 82 this.wordSize = wordSize; 83 this.iv = new byte[2*(wordSize/8)]; 84 System.arraycopy(iv, 0, this.iv, 0, 2*(wordSize/8)); 85 } 86 87 /** 88 * Creates a new <code>RC5ParameterSpec</code> instance with the specified 89 * version, round count, wordSize (in bits), an <i>initialization vector</i> 90 * and an offset. 91 * <p> 92 * The size of the <i>initialization vector</i> must be at least 93 * <code>offset + (2 * (wordSize / 8))</code> bytes. The bytes starting at 94 * <code>offset</code> are copied to protect them against modification. 95 * 96 * @param version 97 * the version. 98 * @param rounds 99 * the round count. 100 * @param wordSize 101 * the word size (in bits). 102 * @param iv 103 * the initialization vector. 104 * @param offset 105 * the offset in the initialization vector. 106 * @throws IllegalArgumentException 107 * if the initialization vector is null of shorter than 108 * <code>offset + (2 * (wordSize / 8))</code>. 109 * @throws ArrayIndexOutOfBoundsException 110 * if <code>offset</code> is negative. 111 */ 112 public RC5ParameterSpec(int version, int rounds, int wordSize, byte[] iv, int offset) { 113 if (iv == null) { 114 throw new IllegalArgumentException("iv == null"); 115 } 116 if (offset < 0) { 117 throw new ArrayIndexOutOfBoundsException("offset < 0: " + offset); 118 } 119 if (iv.length - offset < 2 * (wordSize / 8)) { 120 throw new IllegalArgumentException("iv.length - offset < 2 * (wordSize / 8)"); 121 } 122 this.version = version; 123 this.rounds = rounds; 124 this.wordSize = wordSize; 125 this.iv = new byte[offset+2*(wordSize/8)]; 126 System.arraycopy(iv, offset, this.iv, 0, 2*(wordSize/8)); 127 } 128 129 /** 130 * Returns the version. 131 * 132 * @return the version. 133 */ 134 public int getVersion() { 135 return version; 136 } 137 138 /** 139 * Returns the round count. 140 * 141 * @return the round count. 142 */ 143 public int getRounds() { 144 return rounds; 145 } 146 147 /** 148 * Returns the word size (in bits). 149 * 150 * @return the word size (in bits). 151 */ 152 public int getWordSize() { 153 return wordSize; 154 } 155 156 /** 157 * Returns a copy of the initialization vector. 158 * 159 * @return a copy of the initialization vector, or null if none specified. 160 */ 161 public byte[] getIV() { 162 if (iv == null) { 163 return null; 164 } 165 byte[] result = new byte[iv.length]; 166 System.arraycopy(iv, 0, result, 0, iv.length); 167 return result; 168 } 169 170 /** 171 * Compares the specified object with this <code>RC5ParameterSpec</code> 172 * instance. 173 * 174 * @param obj 175 * the object to compare. 176 * @return true if version, round count, word size and initializaion vector 177 * of both objects are equal, otherwise false. 178 */ 179 @Override 180 public boolean equals(Object obj) { 181 if (obj == this) { 182 return true; 183 } 184 if (!(obj instanceof RC5ParameterSpec)) { 185 return false; 186 } 187 RC5ParameterSpec ps = (RC5ParameterSpec) obj; 188 return (version == ps.version) 189 && (rounds == ps.rounds) 190 && (wordSize == ps.wordSize) 191 && (Arrays.equals(iv, ps.iv)); 192 } 193 194 /** 195 * Returns the hash code of this <code>RC5ParameterSpec</code> instance. 196 * 197 * @return the hash code. 198 */ 199 @Override 200 public int hashCode() { 201 int result = version + rounds + wordSize; 202 if (iv == null) { 203 return result; 204 } 205 for (byte element : iv) { 206 result += element & 0xFF; 207 } 208 return result; 209 } 210 } 211
