1 /* 2 * Copyright (c) 2003, 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.rsa; 27 28 import java.io.IOException; 29 import java.math.BigInteger; 30 31 import java.security.*; 32 import java.security.interfaces.*; 33 34 import sun.security.util.*; 35 import sun.security.x509.X509Key; 36 37 /** 38 * Key implementation for RSA public keys. 39 * 40 * Note: RSA keys must be at least 512 bits long 41 * 42 * @see RSAPrivateCrtKeyImpl 43 * @see RSAKeyFactory 44 * 45 * @since 1.5 46 * @author Andreas Sterbenz 47 */ 48 public final class RSAPublicKeyImpl extends X509Key implements RSAPublicKey { 49 50 private static final long serialVersionUID = 2644735423591199609L; 51 52 private BigInteger n; // modulus 53 private BigInteger e; // public exponent 54 55 /** 56 * Construct a key from its components. Used by the 57 * RSAKeyFactory and the RSAKeyPairGenerator. 58 */ 59 public RSAPublicKeyImpl(BigInteger n, BigInteger e) 60 throws InvalidKeyException { 61 this.n = n; 62 this.e = e; 63 RSAKeyFactory.checkRSAProviderKeyLengths(n.bitLength(), e); 64 // generate the encoding 65 algid = RSAPrivateCrtKeyImpl.rsaId; 66 try { 67 DerOutputStream out = new DerOutputStream(); 68 out.putInteger(n); 69 out.putInteger(e); 70 byte[] keyArray = 71 new DerValue(DerValue.tag_Sequence, 72 out.toByteArray()).toByteArray(); 73 setKey(new BitArray(keyArray.length*8, keyArray)); 74 } catch (IOException exc) { 75 // should never occur 76 throw new InvalidKeyException(exc); 77 } 78 } 79 80 /** 81 * Construct a key from its encoding. Used by RSAKeyFactory. 82 */ 83 public RSAPublicKeyImpl(byte[] encoded) throws InvalidKeyException { 84 decode(encoded); 85 RSAKeyFactory.checkRSAProviderKeyLengths(n.bitLength(), e); 86 } 87 88 // see JCA doc 89 public String getAlgorithm() { 90 return "RSA"; 91 } 92 93 // see JCA doc 94 public BigInteger getModulus() { 95 return n; 96 } 97 98 // see JCA doc 99 public BigInteger getPublicExponent() { 100 return e; 101 } 102 103 /** 104 * Parse the key. Called by X509Key. 105 */ 106 protected void parseKeyBits() throws InvalidKeyException { 107 try { 108 DerInputStream in = new DerInputStream(getKey().toByteArray()); 109 DerValue derValue = in.getDerValue(); 110 if (derValue.tag != DerValue.tag_Sequence) { 111 throw new IOException("Not a SEQUENCE"); 112 } 113 DerInputStream data = derValue.data; 114 n = RSAPrivateCrtKeyImpl.getBigInteger(data); 115 e = RSAPrivateCrtKeyImpl.getBigInteger(data); 116 if (derValue.data.available() != 0) { 117 throw new IOException("Extra data available"); 118 } 119 } catch (IOException e) { 120 throw new InvalidKeyException("Invalid RSA public key", e); 121 } 122 } 123 124 // return a string representation of this key for debugging 125 public String toString() { 126 return "Sun RSA public key, " + n.bitLength() + " bits\n modulus: " 127 + n + "\n public exponent: " + e; 128 } 129 130 protected Object writeReplace() throws java.io.ObjectStreamException { 131 return new KeyRep(KeyRep.Type.PUBLIC, 132 getAlgorithm(), 133 getFormat(), 134 getEncoded()); 135 } 136 }