J. Duke | 319a3b9 | 2007-12-01 00:00:00 +0000 | [diff] [blame^] | 1 | /* |
| 2 | * Copyright 2003-2006 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 sun.security.rsa; |
| 27 | |
| 28 | import java.io.IOException; |
| 29 | import java.nio.ByteBuffer; |
| 30 | import java.math.BigInteger; |
| 31 | import java.util.Arrays; |
| 32 | |
| 33 | import java.security.*; |
| 34 | import java.security.interfaces.*; |
| 35 | |
| 36 | import sun.security.util.*; |
| 37 | import sun.security.x509.AlgorithmId; |
| 38 | |
| 39 | /** |
| 40 | * PKCS#1 RSA signatures with the various message digest algorithms. |
| 41 | * This file contains an abstract base class with all the logic plus |
| 42 | * a nested static class for each of the message digest algorithms |
| 43 | * (see end of the file). We support MD2, MD5, SHA-1, SHA-256, SHA-384, |
| 44 | * and SHA-512. |
| 45 | * |
| 46 | * @since 1.5 |
| 47 | * @author Andreas Sterbenz |
| 48 | */ |
| 49 | public abstract class RSASignature extends SignatureSpi { |
| 50 | |
| 51 | // we sign an ASN.1 SEQUENCE of AlgorithmId and digest |
| 52 | // it has the form 30:xx:30:0c:[digestOID]:05:00:04:xx:[digest] |
| 53 | // this means the encoded length is (8 + digestOID.length + digest.length) |
| 54 | private static final int baseLength = 8; |
| 55 | |
| 56 | // object identifier for the message digest algorithm used |
| 57 | private final ObjectIdentifier digestOID; |
| 58 | |
| 59 | // length of the encoded signature blob |
| 60 | private final int encodedLength; |
| 61 | |
| 62 | // message digest implementation we use |
| 63 | private final MessageDigest md; |
| 64 | // flag indicating whether the digest is reset |
| 65 | private boolean digestReset; |
| 66 | |
| 67 | // private key, if initialized for signing |
| 68 | private RSAPrivateKey privateKey; |
| 69 | // public key, if initialized for verifying |
| 70 | private RSAPublicKey publicKey; |
| 71 | |
| 72 | // padding to use, set when the initSign/initVerify is called |
| 73 | private RSAPadding padding; |
| 74 | |
| 75 | /** |
| 76 | * Construct a new RSASignature. Used by subclasses. |
| 77 | */ |
| 78 | RSASignature(String algorithm, ObjectIdentifier digestOID, int oidLength) { |
| 79 | this.digestOID = digestOID; |
| 80 | try { |
| 81 | md = MessageDigest.getInstance(algorithm); |
| 82 | } catch (NoSuchAlgorithmException e) { |
| 83 | throw new ProviderException(e); |
| 84 | } |
| 85 | digestReset = true; |
| 86 | encodedLength = baseLength + oidLength + md.getDigestLength(); |
| 87 | } |
| 88 | |
| 89 | // initialize for verification. See JCA doc |
| 90 | protected void engineInitVerify(PublicKey publicKey) |
| 91 | throws InvalidKeyException { |
| 92 | RSAPublicKey rsaKey = (RSAPublicKey)RSAKeyFactory.toRSAKey(publicKey); |
| 93 | this.privateKey = null; |
| 94 | this.publicKey = rsaKey; |
| 95 | initCommon(rsaKey, null); |
| 96 | } |
| 97 | |
| 98 | // initialize for signing. See JCA doc |
| 99 | protected void engineInitSign(PrivateKey privateKey) |
| 100 | throws InvalidKeyException { |
| 101 | engineInitSign(privateKey, null); |
| 102 | } |
| 103 | |
| 104 | // initialize for signing. See JCA doc |
| 105 | protected void engineInitSign(PrivateKey privateKey, SecureRandom random) |
| 106 | throws InvalidKeyException { |
| 107 | RSAPrivateKey rsaKey = (RSAPrivateKey)RSAKeyFactory.toRSAKey(privateKey); |
| 108 | this.privateKey = rsaKey; |
| 109 | this.publicKey = null; |
| 110 | initCommon(rsaKey, random); |
| 111 | } |
| 112 | |
| 113 | /** |
| 114 | * Init code common to sign and verify. |
| 115 | */ |
| 116 | private void initCommon(RSAKey rsaKey, SecureRandom random) |
| 117 | throws InvalidKeyException { |
| 118 | resetDigest(); |
| 119 | int keySize = RSACore.getByteLength(rsaKey); |
| 120 | try { |
| 121 | padding = RSAPadding.getInstance |
| 122 | (RSAPadding.PAD_BLOCKTYPE_1, keySize, random); |
| 123 | } catch (InvalidAlgorithmParameterException iape) { |
| 124 | throw new InvalidKeyException(iape.getMessage()); |
| 125 | } |
| 126 | int maxDataSize = padding.getMaxDataSize(); |
| 127 | if (encodedLength > maxDataSize) { |
| 128 | throw new InvalidKeyException |
| 129 | ("Key is too short for this signature algorithm"); |
| 130 | } |
| 131 | } |
| 132 | |
| 133 | /** |
| 134 | * Reset the message digest if it is not already reset. |
| 135 | */ |
| 136 | private void resetDigest() { |
| 137 | if (digestReset == false) { |
| 138 | md.reset(); |
| 139 | digestReset = true; |
| 140 | } |
| 141 | } |
| 142 | |
| 143 | /** |
| 144 | * Return the message digest value. |
| 145 | */ |
| 146 | private byte[] getDigestValue() { |
| 147 | digestReset = true; |
| 148 | return md.digest(); |
| 149 | } |
| 150 | |
| 151 | // update the signature with the plaintext data. See JCA doc |
| 152 | protected void engineUpdate(byte b) throws SignatureException { |
| 153 | md.update(b); |
| 154 | digestReset = false; |
| 155 | } |
| 156 | |
| 157 | // update the signature with the plaintext data. See JCA doc |
| 158 | protected void engineUpdate(byte[] b, int off, int len) |
| 159 | throws SignatureException { |
| 160 | md.update(b, off, len); |
| 161 | digestReset = false; |
| 162 | } |
| 163 | |
| 164 | // update the signature with the plaintext data. See JCA doc |
| 165 | protected void engineUpdate(ByteBuffer b) { |
| 166 | md.update(b); |
| 167 | digestReset = false; |
| 168 | } |
| 169 | |
| 170 | // sign the data and return the signature. See JCA doc |
| 171 | protected byte[] engineSign() throws SignatureException { |
| 172 | byte[] digest = getDigestValue(); |
| 173 | try { |
| 174 | byte[] encoded = encodeSignature(digestOID, digest); |
| 175 | byte[] padded = padding.pad(encoded); |
| 176 | byte[] encrypted = RSACore.rsa(padded, privateKey); |
| 177 | return encrypted; |
| 178 | } catch (GeneralSecurityException e) { |
| 179 | throw new SignatureException("Could not sign data", e); |
| 180 | } catch (IOException e) { |
| 181 | throw new SignatureException("Could not encode data", e); |
| 182 | } |
| 183 | } |
| 184 | |
| 185 | // verify the data and return the result. See JCA doc |
| 186 | protected boolean engineVerify(byte[] sigBytes) throws SignatureException { |
| 187 | byte[] digest = getDigestValue(); |
| 188 | try { |
| 189 | byte[] decrypted = RSACore.rsa(sigBytes, publicKey); |
| 190 | byte[] unpadded = padding.unpad(decrypted); |
| 191 | byte[] decodedDigest = decodeSignature(digestOID, unpadded); |
| 192 | return Arrays.equals(digest, decodedDigest); |
| 193 | } catch (javax.crypto.BadPaddingException e) { |
| 194 | // occurs if the app has used the wrong RSA public key |
| 195 | // or if sigBytes is invalid |
| 196 | // return false rather than propagating the exception for |
| 197 | // compatibility/ease of use |
| 198 | return false; |
| 199 | } catch (GeneralSecurityException e) { |
| 200 | throw new SignatureException("Signature verification failed", e); |
| 201 | } catch (IOException e) { |
| 202 | throw new SignatureException("Signature encoding error", e); |
| 203 | } |
| 204 | } |
| 205 | |
| 206 | /** |
| 207 | * Encode the digest, return the to-be-signed data. |
| 208 | * Also used by the PKCS#11 provider. |
| 209 | */ |
| 210 | public static byte[] encodeSignature(ObjectIdentifier oid, byte[] digest) |
| 211 | throws IOException { |
| 212 | DerOutputStream out = new DerOutputStream(); |
| 213 | new AlgorithmId(oid).encode(out); |
| 214 | out.putOctetString(digest); |
| 215 | DerValue result = new DerValue(DerValue.tag_Sequence, out.toByteArray()); |
| 216 | return result.toByteArray(); |
| 217 | } |
| 218 | |
| 219 | /** |
| 220 | * Decode the signature data. Verify that the object identifier matches |
| 221 | * and return the message digest. |
| 222 | */ |
| 223 | public static byte[] decodeSignature(ObjectIdentifier oid, byte[] signature) |
| 224 | throws IOException { |
| 225 | DerInputStream in = new DerInputStream(signature); |
| 226 | DerValue[] values = in.getSequence(2); |
| 227 | if ((values.length != 2) || (in.available() != 0)) { |
| 228 | throw new IOException("SEQUENCE length error"); |
| 229 | } |
| 230 | AlgorithmId algId = AlgorithmId.parse(values[0]); |
| 231 | if (algId.getOID().equals(oid) == false) { |
| 232 | throw new IOException("ObjectIdentifier mismatch: " + algId.getOID()); |
| 233 | } |
| 234 | if (algId.getEncodedParams() != null) { |
| 235 | throw new IOException("Unexpected AlgorithmId parameters"); |
| 236 | } |
| 237 | byte[] digest = values[1].getOctetString(); |
| 238 | return digest; |
| 239 | } |
| 240 | |
| 241 | // set parameter, not supported. See JCA doc |
| 242 | protected void engineSetParameter(String param, Object value) |
| 243 | throws InvalidParameterException { |
| 244 | throw new UnsupportedOperationException("setParameter() not supported"); |
| 245 | } |
| 246 | |
| 247 | // get parameter, not supported. See JCA doc |
| 248 | protected Object engineGetParameter(String param) |
| 249 | throws InvalidParameterException { |
| 250 | throw new UnsupportedOperationException("getParameter() not supported"); |
| 251 | } |
| 252 | |
| 253 | // Nested class for MD2withRSA signatures |
| 254 | public static final class MD2withRSA extends RSASignature { |
| 255 | public MD2withRSA() { |
| 256 | super("MD2", AlgorithmId.MD2_oid, 10); |
| 257 | } |
| 258 | } |
| 259 | |
| 260 | // Nested class for MD5withRSA signatures |
| 261 | public static final class MD5withRSA extends RSASignature { |
| 262 | public MD5withRSA() { |
| 263 | super("MD5", AlgorithmId.MD5_oid, 10); |
| 264 | } |
| 265 | } |
| 266 | |
| 267 | // Nested class for SHA1withRSA signatures |
| 268 | public static final class SHA1withRSA extends RSASignature { |
| 269 | public SHA1withRSA() { |
| 270 | super("SHA-1", AlgorithmId.SHA_oid, 7); |
| 271 | } |
| 272 | } |
| 273 | |
| 274 | // Nested class for SHA256withRSA signatures |
| 275 | public static final class SHA256withRSA extends RSASignature { |
| 276 | public SHA256withRSA() { |
| 277 | super("SHA-256", AlgorithmId.SHA256_oid, 11); |
| 278 | } |
| 279 | } |
| 280 | |
| 281 | // Nested class for SHA384withRSA signatures |
| 282 | public static final class SHA384withRSA extends RSASignature { |
| 283 | public SHA384withRSA() { |
| 284 | super("SHA-384", AlgorithmId.SHA384_oid, 11); |
| 285 | } |
| 286 | } |
| 287 | |
| 288 | // Nested class for SHA512withRSA signatures |
| 289 | public static final class SHA512withRSA extends RSASignature { |
| 290 | public SHA512withRSA() { |
| 291 | super("SHA-512", AlgorithmId.SHA512_oid, 11); |
| 292 | } |
| 293 | } |
| 294 | |
| 295 | } |