J. Duke | 319a3b9 | 2007-12-01 00:00:00 +0000 | [diff] [blame^] | 1 | /* |
| 2 | * Copyright 2003-2007 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 com.sun.crypto.provider; |
| 27 | |
| 28 | import java.util.Locale; |
| 29 | |
| 30 | import java.security.*; |
| 31 | import java.security.interfaces.*; |
| 32 | import java.security.spec.AlgorithmParameterSpec; |
| 33 | import java.security.spec.InvalidParameterSpecException; |
| 34 | import java.security.spec.MGF1ParameterSpec; |
| 35 | |
| 36 | import javax.crypto.*; |
| 37 | import javax.crypto.spec.PSource; |
| 38 | import javax.crypto.spec.OAEPParameterSpec; |
| 39 | |
| 40 | import sun.security.rsa.*; |
| 41 | import sun.security.jca.Providers; |
| 42 | |
| 43 | /** |
| 44 | * RSA cipher implementation. Supports RSA en/decryption and signing/verifying |
| 45 | * using PKCS#1 v1.5 padding and without padding (raw RSA). Note that raw RSA |
| 46 | * is supported mostly for completeness and should only be used in rare cases. |
| 47 | * |
| 48 | * Objects should be instantiated by calling Cipher.getInstance() using the |
| 49 | * following algorithm names: |
| 50 | * . "RSA/ECB/PKCS1Padding" (or "RSA") for PKCS#1 padding. The mode (blocktype) |
| 51 | * is selected based on the en/decryption mode and public/private key used |
| 52 | * . "RSA/ECB/NoPadding" for rsa RSA. |
| 53 | * |
| 54 | * We only do one RSA operation per doFinal() call. If the application passes |
| 55 | * more data via calls to update() or doFinal(), we throw an |
| 56 | * IllegalBlockSizeException when doFinal() is called (see JCE API spec). |
| 57 | * Bulk encryption using RSA does not make sense and is not standardized. |
| 58 | * |
| 59 | * Note: RSA keys should be at least 512 bits long |
| 60 | * |
| 61 | * @since 1.5 |
| 62 | * @author Andreas Sterbenz |
| 63 | */ |
| 64 | public final class RSACipher extends CipherSpi { |
| 65 | |
| 66 | // constant for an empty byte array |
| 67 | private final static byte[] B0 = new byte[0]; |
| 68 | |
| 69 | // mode constant for public key encryption |
| 70 | private final static int MODE_ENCRYPT = 1; |
| 71 | // mode constant for private key decryption |
| 72 | private final static int MODE_DECRYPT = 2; |
| 73 | // mode constant for private key encryption (signing) |
| 74 | private final static int MODE_SIGN = 3; |
| 75 | // mode constant for public key decryption (verifying) |
| 76 | private final static int MODE_VERIFY = 4; |
| 77 | |
| 78 | // constant for raw RSA |
| 79 | private final static String PAD_NONE = "NoPadding"; |
| 80 | // constant for PKCS#1 v1.5 RSA |
| 81 | private final static String PAD_PKCS1 = "PKCS1Padding"; |
| 82 | // constant for PKCS#2 v2.0 OAEP with MGF1 |
| 83 | private final static String PAD_OAEP_MGF1 = "OAEP"; |
| 84 | |
| 85 | // current mode, one of MODE_* above. Set when init() is called |
| 86 | private int mode; |
| 87 | |
| 88 | // active padding type, one of PAD_* above. Set by setPadding() |
| 89 | private String paddingType; |
| 90 | |
| 91 | // padding object |
| 92 | private RSAPadding padding; |
| 93 | |
| 94 | // cipher parameter for OAEP padding |
| 95 | private OAEPParameterSpec spec = null; |
| 96 | |
| 97 | // buffer for the data |
| 98 | private byte[] buffer; |
| 99 | // offset into the buffer (number of bytes buffered) |
| 100 | private int bufOfs; |
| 101 | |
| 102 | // size of the output |
| 103 | private int outputSize; |
| 104 | |
| 105 | // the public key, if we were initialized using a public key |
| 106 | private RSAPublicKey publicKey; |
| 107 | // the private key, if we were initialized using a private key |
| 108 | private RSAPrivateKey privateKey; |
| 109 | |
| 110 | // hash algorithm for OAEP |
| 111 | private String oaepHashAlgorithm = "SHA-1"; |
| 112 | |
| 113 | public RSACipher() { |
| 114 | SunJCE.ensureIntegrity(getClass()); |
| 115 | paddingType = PAD_PKCS1; |
| 116 | } |
| 117 | |
| 118 | // modes do not make sense for RSA, but allow ECB |
| 119 | // see JCE spec |
| 120 | protected void engineSetMode(String mode) throws NoSuchAlgorithmException { |
| 121 | if (mode.equalsIgnoreCase("ECB") == false) { |
| 122 | throw new NoSuchAlgorithmException("Unsupported mode " + mode); |
| 123 | } |
| 124 | } |
| 125 | |
| 126 | // set the padding type |
| 127 | // see JCE spec |
| 128 | protected void engineSetPadding(String paddingName) |
| 129 | throws NoSuchPaddingException { |
| 130 | if (paddingName.equalsIgnoreCase(PAD_NONE)) { |
| 131 | paddingType = PAD_NONE; |
| 132 | } else if (paddingName.equalsIgnoreCase(PAD_PKCS1)) { |
| 133 | paddingType = PAD_PKCS1; |
| 134 | } else { |
| 135 | String lowerPadding = paddingName.toLowerCase(Locale.ENGLISH); |
| 136 | if (lowerPadding.equals("oaeppadding")) { |
| 137 | paddingType = PAD_OAEP_MGF1; |
| 138 | } else if (lowerPadding.startsWith("oaepwith") && |
| 139 | lowerPadding.endsWith("andmgf1padding")) { |
| 140 | paddingType = PAD_OAEP_MGF1; |
| 141 | // "oaepwith".length() == 8 |
| 142 | // "andmgf1padding".length() == 14 |
| 143 | oaepHashAlgorithm = |
| 144 | paddingName.substring(8, paddingName.length() - 14); |
| 145 | // check if MessageDigest appears to be available |
| 146 | // avoid getInstance() call here |
| 147 | if (Providers.getProviderList().getService |
| 148 | ("MessageDigest", oaepHashAlgorithm) == null) { |
| 149 | throw new NoSuchPaddingException |
| 150 | ("MessageDigest not available for " + paddingName); |
| 151 | } |
| 152 | } else { |
| 153 | throw new NoSuchPaddingException |
| 154 | ("Padding " + paddingName + " not supported"); |
| 155 | } |
| 156 | } |
| 157 | } |
| 158 | |
| 159 | // return 0 as block size, we are not a block cipher |
| 160 | // see JCE spec |
| 161 | protected int engineGetBlockSize() { |
| 162 | return 0; |
| 163 | } |
| 164 | |
| 165 | // return the output size |
| 166 | // see JCE spec |
| 167 | protected int engineGetOutputSize(int inputLen) { |
| 168 | return outputSize; |
| 169 | } |
| 170 | |
| 171 | // no iv, return null |
| 172 | // see JCE spec |
| 173 | protected byte[] engineGetIV() { |
| 174 | return null; |
| 175 | } |
| 176 | |
| 177 | // see JCE spec |
| 178 | protected AlgorithmParameters engineGetParameters() { |
| 179 | if (spec != null) { |
| 180 | try { |
| 181 | AlgorithmParameters params = |
| 182 | AlgorithmParameters.getInstance("OAEP", "SunJCE"); |
| 183 | params.init(spec); |
| 184 | return params; |
| 185 | } catch (NoSuchAlgorithmException nsae) { |
| 186 | // should never happen |
| 187 | throw new RuntimeException("Cannot find OAEP " + |
| 188 | " AlgorithmParameters implementation in SunJCE provider"); |
| 189 | } catch (NoSuchProviderException nspe) { |
| 190 | // should never happen |
| 191 | throw new RuntimeException("Cannot find SunJCE provider"); |
| 192 | } catch (InvalidParameterSpecException ipse) { |
| 193 | // should never happen |
| 194 | throw new RuntimeException("OAEPParameterSpec not supported"); |
| 195 | } |
| 196 | } else { |
| 197 | return null; |
| 198 | } |
| 199 | } |
| 200 | |
| 201 | // see JCE spec |
| 202 | protected void engineInit(int opmode, Key key, SecureRandom random) |
| 203 | throws InvalidKeyException { |
| 204 | try { |
| 205 | init(opmode, key, random, null); |
| 206 | } catch (InvalidAlgorithmParameterException iape) { |
| 207 | // never thrown when null parameters are used; |
| 208 | // but re-throw it just in case |
| 209 | InvalidKeyException ike = |
| 210 | new InvalidKeyException("Wrong parameters"); |
| 211 | ike.initCause(iape); |
| 212 | throw ike; |
| 213 | } |
| 214 | } |
| 215 | |
| 216 | // see JCE spec |
| 217 | protected void engineInit(int opmode, Key key, |
| 218 | AlgorithmParameterSpec params, SecureRandom random) |
| 219 | throws InvalidKeyException, InvalidAlgorithmParameterException { |
| 220 | init(opmode, key, random, params); |
| 221 | } |
| 222 | |
| 223 | // see JCE spec |
| 224 | protected void engineInit(int opmode, Key key, |
| 225 | AlgorithmParameters params, SecureRandom random) |
| 226 | throws InvalidKeyException, InvalidAlgorithmParameterException { |
| 227 | if (params == null) { |
| 228 | init(opmode, key, random, null); |
| 229 | } else { |
| 230 | try { |
| 231 | OAEPParameterSpec spec = (OAEPParameterSpec) |
| 232 | params.getParameterSpec(OAEPParameterSpec.class); |
| 233 | init(opmode, key, random, spec); |
| 234 | } catch (InvalidParameterSpecException ipse) { |
| 235 | InvalidAlgorithmParameterException iape = |
| 236 | new InvalidAlgorithmParameterException("Wrong parameter"); |
| 237 | iape.initCause(ipse); |
| 238 | throw iape; |
| 239 | } |
| 240 | } |
| 241 | } |
| 242 | |
| 243 | // initialize this cipher |
| 244 | private void init(int opmode, Key key, SecureRandom random, |
| 245 | AlgorithmParameterSpec params) |
| 246 | throws InvalidKeyException, InvalidAlgorithmParameterException { |
| 247 | boolean encrypt; |
| 248 | switch (opmode) { |
| 249 | case Cipher.ENCRYPT_MODE: |
| 250 | case Cipher.WRAP_MODE: |
| 251 | encrypt = true; |
| 252 | break; |
| 253 | case Cipher.DECRYPT_MODE: |
| 254 | case Cipher.UNWRAP_MODE: |
| 255 | encrypt = false; |
| 256 | break; |
| 257 | default: |
| 258 | throw new InvalidKeyException("Unknown mode: " + opmode); |
| 259 | } |
| 260 | RSAKey rsaKey = RSAKeyFactory.toRSAKey(key); |
| 261 | if (key instanceof RSAPublicKey) { |
| 262 | mode = encrypt ? MODE_ENCRYPT : MODE_VERIFY; |
| 263 | publicKey = (RSAPublicKey)key; |
| 264 | privateKey = null; |
| 265 | } else { // must be RSAPrivateKey per check in toRSAKey |
| 266 | mode = encrypt ? MODE_SIGN : MODE_DECRYPT; |
| 267 | privateKey = (RSAPrivateKey)key; |
| 268 | publicKey = null; |
| 269 | } |
| 270 | int n = RSACore.getByteLength(rsaKey.getModulus()); |
| 271 | outputSize = n; |
| 272 | bufOfs = 0; |
| 273 | if (paddingType == PAD_NONE) { |
| 274 | if (params != null) { |
| 275 | throw new InvalidAlgorithmParameterException |
| 276 | ("Parameters not supported"); |
| 277 | } |
| 278 | padding = RSAPadding.getInstance(RSAPadding.PAD_NONE, n, random); |
| 279 | buffer = new byte[n]; |
| 280 | } else if (paddingType == PAD_PKCS1) { |
| 281 | if (params != null) { |
| 282 | throw new InvalidAlgorithmParameterException |
| 283 | ("Parameters not supported"); |
| 284 | } |
| 285 | int blockType = (mode <= MODE_DECRYPT) ? RSAPadding.PAD_BLOCKTYPE_2 |
| 286 | : RSAPadding.PAD_BLOCKTYPE_1; |
| 287 | padding = RSAPadding.getInstance(blockType, n, random); |
| 288 | if (encrypt) { |
| 289 | int k = padding.getMaxDataSize(); |
| 290 | buffer = new byte[k]; |
| 291 | } else { |
| 292 | buffer = new byte[n]; |
| 293 | } |
| 294 | } else { // PAD_OAEP_MGF1 |
| 295 | if ((mode == MODE_SIGN) || (mode == MODE_VERIFY)) { |
| 296 | throw new InvalidKeyException |
| 297 | ("OAEP cannot be used to sign or verify signatures"); |
| 298 | } |
| 299 | OAEPParameterSpec myParams; |
| 300 | if (params != null) { |
| 301 | if (!(params instanceof OAEPParameterSpec)) { |
| 302 | throw new InvalidAlgorithmParameterException |
| 303 | ("Wrong Parameters for OAEP Padding"); |
| 304 | } |
| 305 | myParams = (OAEPParameterSpec) params; |
| 306 | } else { |
| 307 | myParams = new OAEPParameterSpec(oaepHashAlgorithm, "MGF1", |
| 308 | MGF1ParameterSpec.SHA1, PSource.PSpecified.DEFAULT); |
| 309 | } |
| 310 | padding = RSAPadding.getInstance(RSAPadding.PAD_OAEP_MGF1, n, |
| 311 | random, myParams); |
| 312 | if (encrypt) { |
| 313 | int k = padding.getMaxDataSize(); |
| 314 | buffer = new byte[k]; |
| 315 | } else { |
| 316 | buffer = new byte[n]; |
| 317 | } |
| 318 | } |
| 319 | } |
| 320 | |
| 321 | // internal update method |
| 322 | private void update(byte[] in, int inOfs, int inLen) { |
| 323 | if ((inLen == 0) || (in == null)) { |
| 324 | return; |
| 325 | } |
| 326 | if (bufOfs + inLen > buffer.length) { |
| 327 | bufOfs = buffer.length + 1; |
| 328 | return; |
| 329 | } |
| 330 | System.arraycopy(in, inOfs, buffer, bufOfs, inLen); |
| 331 | bufOfs += inLen; |
| 332 | } |
| 333 | |
| 334 | // internal doFinal() method. Here we perform the actual RSA operation |
| 335 | private byte[] doFinal() throws BadPaddingException, |
| 336 | IllegalBlockSizeException { |
| 337 | if (bufOfs > buffer.length) { |
| 338 | throw new IllegalBlockSizeException("Data must not be longer " |
| 339 | + "than " + buffer.length + " bytes"); |
| 340 | } |
| 341 | try { |
| 342 | byte[] data; |
| 343 | switch (mode) { |
| 344 | case MODE_SIGN: |
| 345 | data = padding.pad(buffer, 0, bufOfs); |
| 346 | return RSACore.rsa(data, privateKey); |
| 347 | case MODE_VERIFY: |
| 348 | byte[] verifyBuffer = RSACore.convert(buffer, 0, bufOfs); |
| 349 | data = RSACore.rsa(verifyBuffer, publicKey); |
| 350 | return padding.unpad(data); |
| 351 | case MODE_ENCRYPT: |
| 352 | data = padding.pad(buffer, 0, bufOfs); |
| 353 | return RSACore.rsa(data, publicKey); |
| 354 | case MODE_DECRYPT: |
| 355 | byte[] decryptBuffer = RSACore.convert(buffer, 0, bufOfs); |
| 356 | data = RSACore.rsa(decryptBuffer, privateKey); |
| 357 | return padding.unpad(data); |
| 358 | default: |
| 359 | throw new AssertionError("Internal error"); |
| 360 | } |
| 361 | } finally { |
| 362 | bufOfs = 0; |
| 363 | } |
| 364 | } |
| 365 | |
| 366 | // see JCE spec |
| 367 | protected byte[] engineUpdate(byte[] in, int inOfs, int inLen) { |
| 368 | update(in, inOfs, inLen); |
| 369 | return B0; |
| 370 | } |
| 371 | |
| 372 | // see JCE spec |
| 373 | protected int engineUpdate(byte[] in, int inOfs, int inLen, byte[] out, |
| 374 | int outOfs) { |
| 375 | update(in, inOfs, inLen); |
| 376 | return 0; |
| 377 | } |
| 378 | |
| 379 | // see JCE spec |
| 380 | protected byte[] engineDoFinal(byte[] in, int inOfs, int inLen) |
| 381 | throws BadPaddingException, IllegalBlockSizeException { |
| 382 | update(in, inOfs, inLen); |
| 383 | return doFinal(); |
| 384 | } |
| 385 | |
| 386 | // see JCE spec |
| 387 | protected int engineDoFinal(byte[] in, int inOfs, int inLen, byte[] out, |
| 388 | int outOfs) throws ShortBufferException, BadPaddingException, |
| 389 | IllegalBlockSizeException { |
| 390 | if (outputSize > out.length - outOfs) { |
| 391 | throw new ShortBufferException |
| 392 | ("Need " + outputSize + " bytes for output"); |
| 393 | } |
| 394 | update(in, inOfs, inLen); |
| 395 | byte[] result = doFinal(); |
| 396 | int n = result.length; |
| 397 | System.arraycopy(result, 0, out, outOfs, n); |
| 398 | return n; |
| 399 | } |
| 400 | |
| 401 | // see JCE spec |
| 402 | protected byte[] engineWrap(Key key) throws InvalidKeyException, |
| 403 | IllegalBlockSizeException { |
| 404 | byte[] encoded = key.getEncoded(); |
| 405 | if ((encoded == null) || (encoded.length == 0)) { |
| 406 | throw new InvalidKeyException("Could not obtain encoded key"); |
| 407 | } |
| 408 | if (encoded.length > buffer.length) { |
| 409 | throw new InvalidKeyException("Key is too long for wrapping"); |
| 410 | } |
| 411 | update(encoded, 0, encoded.length); |
| 412 | try { |
| 413 | return doFinal(); |
| 414 | } catch (BadPaddingException e) { |
| 415 | // should not occur |
| 416 | throw new InvalidKeyException("Wrapping failed", e); |
| 417 | } |
| 418 | } |
| 419 | |
| 420 | // see JCE spec |
| 421 | protected Key engineUnwrap(byte[] wrappedKey, String algorithm, |
| 422 | int type) throws InvalidKeyException, NoSuchAlgorithmException { |
| 423 | if (wrappedKey.length > buffer.length) { |
| 424 | throw new InvalidKeyException("Key is too long for unwrapping"); |
| 425 | } |
| 426 | update(wrappedKey, 0, wrappedKey.length); |
| 427 | try { |
| 428 | byte[] encoded = doFinal(); |
| 429 | return ConstructKeys.constructKey(encoded, algorithm, type); |
| 430 | } catch (BadPaddingException e) { |
| 431 | // should not occur |
| 432 | throw new InvalidKeyException("Unwrapping failed", e); |
| 433 | } catch (IllegalBlockSizeException e) { |
| 434 | // should not occur, handled with length check above |
| 435 | throw new InvalidKeyException("Unwrapping failed", e); |
| 436 | } |
| 437 | } |
| 438 | |
| 439 | // see JCE spec |
| 440 | protected int engineGetKeySize(Key key) throws InvalidKeyException { |
| 441 | RSAKey rsaKey = RSAKeyFactory.toRSAKey(key); |
| 442 | return rsaKey.getModulus().bitLength(); |
| 443 | } |
| 444 | |
| 445 | } |