| /* |
| * Copyright (c) 2003, 2007, Oracle and/or its affiliates. All rights reserved. |
| * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. |
| * |
| * This code is free software; you can redistribute it and/or modify it |
| * under the terms of the GNU General Public License version 2 only, as |
| * published by the Free Software Foundation. Oracle designates this |
| * particular file as subject to the "Classpath" exception as provided |
| * by Oracle in the LICENSE file that accompanied this code. |
| * |
| * This code is distributed in the hope that it will be useful, but WITHOUT |
| * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or |
| * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License |
| * version 2 for more details (a copy is included in the LICENSE file that |
| * accompanied this code). |
| * |
| * You should have received a copy of the GNU General Public License version |
| * 2 along with this work; if not, write to the Free Software Foundation, |
| * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. |
| * |
| * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA |
| * or visit www.oracle.com if you need additional information or have any |
| * questions. |
| */ |
| |
| package com.sun.crypto.provider; |
| |
| import java.security.InvalidKeyException; |
| |
| /** |
| * Implementation of the RC2(tm) algorithm as described in RFC 2268. |
| * |
| * RC2 is a 16-bit based algorithm and not particularly fast on 32/64 bit |
| * architectures. Also, note that although the JVM has a 16-bit integer |
| * type (short), all expressions are evaluated either in 32 or 64 bit |
| * (int or long). Expression such as "s1 = s2 + s3" are implemented by |
| * first promoting s2 and s3 to int, performing an int addition, and |
| * then demoting the result back to short to store in s1. To avoid this |
| * fairly slow process, we use the int type throughout and manually insert |
| * "& 0xffff" where necessary. |
| * |
| * @since 1.5 |
| * @author Andreas Sterbenz |
| */ |
| final class RC2Crypt extends SymmetricCipher { |
| |
| // PITABLE from the RFC, used in key setup |
| private final static int[] PI_TABLE = new int[] { |
| 0xd9, 0x78, 0xf9, 0xc4, 0x19, 0xdd, 0xb5, 0xed, |
| 0x28, 0xe9, 0xfd, 0x79, 0x4a, 0xa0, 0xd8, 0x9d, |
| 0xc6, 0x7e, 0x37, 0x83, 0x2b, 0x76, 0x53, 0x8e, |
| 0x62, 0x4c, 0x64, 0x88, 0x44, 0x8b, 0xfb, 0xa2, |
| 0x17, 0x9a, 0x59, 0xf5, 0x87, 0xb3, 0x4f, 0x13, |
| 0x61, 0x45, 0x6d, 0x8d, 0x09, 0x81, 0x7d, 0x32, |
| 0xbd, 0x8f, 0x40, 0xeb, 0x86, 0xb7, 0x7b, 0x0b, |
| 0xf0, 0x95, 0x21, 0x22, 0x5c, 0x6b, 0x4e, 0x82, |
| 0x54, 0xd6, 0x65, 0x93, 0xce, 0x60, 0xb2, 0x1c, |
| 0x73, 0x56, 0xc0, 0x14, 0xa7, 0x8c, 0xf1, 0xdc, |
| 0x12, 0x75, 0xca, 0x1f, 0x3b, 0xbe, 0xe4, 0xd1, |
| 0x42, 0x3d, 0xd4, 0x30, 0xa3, 0x3c, 0xb6, 0x26, |
| 0x6f, 0xbf, 0x0e, 0xda, 0x46, 0x69, 0x07, 0x57, |
| 0x27, 0xf2, 0x1d, 0x9b, 0xbc, 0x94, 0x43, 0x03, |
| 0xf8, 0x11, 0xc7, 0xf6, 0x90, 0xef, 0x3e, 0xe7, |
| 0x06, 0xc3, 0xd5, 0x2f, 0xc8, 0x66, 0x1e, 0xd7, |
| 0x08, 0xe8, 0xea, 0xde, 0x80, 0x52, 0xee, 0xf7, |
| 0x84, 0xaa, 0x72, 0xac, 0x35, 0x4d, 0x6a, 0x2a, |
| 0x96, 0x1a, 0xd2, 0x71, 0x5a, 0x15, 0x49, 0x74, |
| 0x4b, 0x9f, 0xd0, 0x5e, 0x04, 0x18, 0xa4, 0xec, |
| 0xc2, 0xe0, 0x41, 0x6e, 0x0f, 0x51, 0xcb, 0xcc, |
| 0x24, 0x91, 0xaf, 0x50, 0xa1, 0xf4, 0x70, 0x39, |
| 0x99, 0x7c, 0x3a, 0x85, 0x23, 0xb8, 0xb4, 0x7a, |
| 0xfc, 0x02, 0x36, 0x5b, 0x25, 0x55, 0x97, 0x31, |
| 0x2d, 0x5d, 0xfa, 0x98, 0xe3, 0x8a, 0x92, 0xae, |
| 0x05, 0xdf, 0x29, 0x10, 0x67, 0x6c, 0xba, 0xc9, |
| 0xd3, 0x00, 0xe6, 0xcf, 0xe1, 0x9e, 0xa8, 0x2c, |
| 0x63, 0x16, 0x01, 0x3f, 0x58, 0xe2, 0x89, 0xa9, |
| 0x0d, 0x38, 0x34, 0x1b, 0xab, 0x33, 0xff, 0xb0, |
| 0xbb, 0x48, 0x0c, 0x5f, 0xb9, 0xb1, 0xcd, 0x2e, |
| 0xc5, 0xf3, 0xdb, 0x47, 0xe5, 0xa5, 0x9c, 0x77, |
| 0x0a, 0xa6, 0x20, 0x68, 0xfe, 0x7f, 0xc1, 0xad, |
| }; |
| |
| // expanded key, 64 times 16-bit words |
| private final int[] expandedKey; |
| |
| // effective key bits |
| private int effectiveKeyBits; |
| |
| RC2Crypt() { |
| expandedKey = new int[64]; |
| } |
| |
| int getBlockSize() { |
| return 8; |
| } |
| |
| int getEffectiveKeyBits() { |
| return effectiveKeyBits; |
| } |
| |
| /** |
| * Initializes the effective key bit size. This method is a hook to |
| * allow RC2Cipher to initialize the effective key size. |
| */ |
| void initEffectiveKeyBits(int effectiveKeyBits) { |
| this.effectiveKeyBits = effectiveKeyBits; |
| } |
| |
| static void checkKey(String algorithm, int keyLength) |
| throws InvalidKeyException { |
| if (algorithm.equals("RC2") == false) { |
| throw new InvalidKeyException("Key algorithm must be RC2"); |
| } |
| if ((keyLength < 5) || (keyLength > 128)) { |
| throw new InvalidKeyException |
| ("RC2 key length must be between 40 and 1024 bit"); |
| } |
| } |
| |
| void init(boolean decrypting, String algorithm, byte[] key) |
| throws InvalidKeyException { |
| int keyLength = key.length; |
| if (effectiveKeyBits == 0) { |
| effectiveKeyBits = keyLength << 3; |
| } |
| |
| checkKey(algorithm, keyLength); |
| |
| // key buffer, the L[] byte array from the spec |
| byte[] expandedKeyBytes = new byte[128]; |
| |
| // place key into key buffer |
| System.arraycopy(key, 0, expandedKeyBytes, 0, keyLength); |
| |
| // first loop |
| int t = expandedKeyBytes[keyLength - 1]; |
| for (int i = keyLength; i < 128; i++) { |
| t = PI_TABLE[(t + expandedKeyBytes[i - keyLength]) & 0xff]; |
| expandedKeyBytes[i] = (byte)t; |
| } |
| |
| int t8 = (effectiveKeyBits + 7) >> 3; |
| int tm = 0xff >> (-effectiveKeyBits & 7); |
| |
| // second loop, reduce search space to effective key bits |
| t = PI_TABLE[expandedKeyBytes[128 - t8] & tm]; |
| expandedKeyBytes[128 - t8] = (byte)t; |
| for (int i = 127 - t8; i >= 0; i--) { |
| t = PI_TABLE[t ^ (expandedKeyBytes[i + t8] & 0xff)]; |
| expandedKeyBytes[i] = (byte)t; |
| } |
| |
| // byte to short conversion, little endian (copy into K[]) |
| for (int i = 0, j = 0; i < 64; i++, j += 2) { |
| t = (expandedKeyBytes[j ] & 0xff) |
| + ((expandedKeyBytes[j + 1] & 0xff) << 8); |
| expandedKey[i] = t; |
| } |
| } |
| |
| /** |
| * Encrypt a single block. Note that in a few places we omit a "& 0xffff" |
| * and allow variables to become larger than 16 bit. This still works |
| * because there is never a 32 bit overflow. |
| */ |
| void encryptBlock(byte[] in, int inOfs, byte[] out, int outOfs) { |
| int R0 = (in[inOfs ] & 0xff) |
| + ((in[inOfs + 1] & 0xff) << 8); |
| int R1 = (in[inOfs + 2] & 0xff) |
| + ((in[inOfs + 3] & 0xff) << 8); |
| int R2 = (in[inOfs + 4] & 0xff) |
| + ((in[inOfs + 5] & 0xff) << 8); |
| int R3 = (in[inOfs + 6] & 0xff) |
| + ((in[inOfs + 7] & 0xff) << 8); |
| |
| // 5 mixing rounds |
| for (int i = 0; i < 20; i += 4) { |
| R0 = (R0 + expandedKey[i ] + (R3 & R2) + (~R3 & R1)) & 0xffff; |
| R0 = (R0 << 1) | (R0 >>> 15); |
| |
| R1 = (R1 + expandedKey[i + 1] + (R0 & R3) + (~R0 & R2)) & 0xffff; |
| R1 = (R1 << 2) | (R1 >>> 14); |
| |
| R2 = (R2 + expandedKey[i + 2] + (R1 & R0) + (~R1 & R3)) & 0xffff; |
| R2 = (R2 << 3) | (R2 >>> 13); |
| |
| R3 = (R3 + expandedKey[i + 3] + (R2 & R1) + (~R2 & R0)) & 0xffff; |
| R3 = (R3 << 5) | (R3 >>> 11); |
| } |
| |
| // 1 mashing round |
| R0 += expandedKey[R3 & 0x3f]; |
| R1 += expandedKey[R0 & 0x3f]; |
| R2 += expandedKey[R1 & 0x3f]; |
| R3 += expandedKey[R2 & 0x3f]; |
| |
| // 6 mixing rounds |
| for (int i = 20; i < 44; i += 4) { |
| R0 = (R0 + expandedKey[i ] + (R3 & R2) + (~R3 & R1)) & 0xffff; |
| R0 = (R0 << 1) | (R0 >>> 15); |
| |
| R1 = (R1 + expandedKey[i + 1] + (R0 & R3) + (~R0 & R2)) & 0xffff; |
| R1 = (R1 << 2) | (R1 >>> 14); |
| |
| R2 = (R2 + expandedKey[i + 2] + (R1 & R0) + (~R1 & R3)) & 0xffff; |
| R2 = (R2 << 3) | (R2 >>> 13); |
| |
| R3 = (R3 + expandedKey[i + 3] + (R2 & R1) + (~R2 & R0)) & 0xffff; |
| R3 = (R3 << 5) | (R3 >>> 11); |
| } |
| |
| // 1 mashing round |
| R0 += expandedKey[R3 & 0x3f]; |
| R1 += expandedKey[R0 & 0x3f]; |
| R2 += expandedKey[R1 & 0x3f]; |
| R3 += expandedKey[R2 & 0x3f]; |
| |
| // 5 mixing rounds |
| for (int i = 44; i < 64; i += 4) { |
| R0 = (R0 + expandedKey[i ] + (R3 & R2) + (~R3 & R1)) & 0xffff; |
| R0 = (R0 << 1) | (R0 >>> 15); |
| |
| R1 = (R1 + expandedKey[i + 1] + (R0 & R3) + (~R0 & R2)) & 0xffff; |
| R1 = (R1 << 2) | (R1 >>> 14); |
| |
| R2 = (R2 + expandedKey[i + 2] + (R1 & R0) + (~R1 & R3)) & 0xffff; |
| R2 = (R2 << 3) | (R2 >>> 13); |
| |
| R3 = (R3 + expandedKey[i + 3] + (R2 & R1) + (~R2 & R0)) & 0xffff; |
| R3 = (R3 << 5) | (R3 >>> 11); |
| } |
| |
| out[outOfs ] = (byte)R0; |
| out[outOfs + 1] = (byte)(R0 >> 8); |
| out[outOfs + 2] = (byte)R1; |
| out[outOfs + 3] = (byte)(R1 >> 8); |
| out[outOfs + 4] = (byte)R2; |
| out[outOfs + 5] = (byte)(R2 >> 8); |
| out[outOfs + 6] = (byte)R3; |
| out[outOfs + 7] = (byte)(R3 >> 8); |
| } |
| |
| void decryptBlock(byte[] in, int inOfs, byte[] out, int outOfs) { |
| int R0 = (in[inOfs ] & 0xff) |
| + ((in[inOfs + 1] & 0xff) << 8); |
| int R1 = (in[inOfs + 2] & 0xff) |
| + ((in[inOfs + 3] & 0xff) << 8); |
| int R2 = (in[inOfs + 4] & 0xff) |
| + ((in[inOfs + 5] & 0xff) << 8); |
| int R3 = (in[inOfs + 6] & 0xff) |
| + ((in[inOfs + 7] & 0xff) << 8); |
| |
| // 5 r-mixing rounds |
| for(int i = 64; i > 44; i -= 4) { |
| R3 = ((R3 << 11) | (R3 >>> 5)) & 0xffff; |
| R3 = (R3 - expandedKey[i - 1] - (R2 & R1) - (~R2 & R0)) & 0xffff; |
| |
| R2 = ((R2 << 13) | (R2 >>> 3)) & 0xffff; |
| R2 = (R2 - expandedKey[i - 2] - (R1 & R0) - (~R1 & R3)) & 0xffff; |
| |
| R1 = ((R1 << 14) | (R1 >>> 2)) & 0xffff; |
| R1 = (R1 - expandedKey[i - 3] - (R0 & R3) - (~R0 & R2)) & 0xffff; |
| |
| R0 = ((R0 << 15) | (R0 >>> 1)) & 0xffff; |
| R0 = (R0 - expandedKey[i - 4] - (R3 & R2) - (~R3 & R1)) & 0xffff; |
| } |
| |
| // 1 r-mashing round |
| R3 = (R3 - expandedKey[R2 & 0x3f]) & 0xffff; |
| R2 = (R2 - expandedKey[R1 & 0x3f]) & 0xffff; |
| R1 = (R1 - expandedKey[R0 & 0x3f]) & 0xffff; |
| R0 = (R0 - expandedKey[R3 & 0x3f]) & 0xffff; |
| |
| // 6 r-mixing rounds |
| for(int i = 44; i > 20; i -= 4) { |
| R3 = ((R3 << 11) | (R3 >>> 5)) & 0xffff; |
| R3 = (R3 - expandedKey[i - 1] - (R2 & R1) - (~R2 & R0)) & 0xffff; |
| |
| R2 = ((R2 << 13) | (R2 >>> 3)) & 0xffff; |
| R2 = (R2 - expandedKey[i - 2] - (R1 & R0) - (~R1 & R3)) & 0xffff; |
| |
| R1 = ((R1 << 14) | (R1 >>> 2)) & 0xffff; |
| R1 = (R1 - expandedKey[i - 3] - (R0 & R3) - (~R0 & R2)) & 0xffff; |
| |
| R0 = ((R0 << 15) | (R0 >>> 1)) & 0xffff; |
| R0 = (R0 - expandedKey[i - 4] - (R3 & R2) - (~R3 & R1)) & 0xffff; |
| } |
| |
| // 1 r-mashing round |
| R3 = (R3 - expandedKey[R2 & 0x3f]) & 0xffff; |
| R2 = (R2 - expandedKey[R1 & 0x3f]) & 0xffff; |
| R1 = (R1 - expandedKey[R0 & 0x3f]) & 0xffff; |
| R0 = (R0 - expandedKey[R3 & 0x3f]) & 0xffff; |
| |
| // 5 r-mixing rounds |
| for(int i = 20; i > 0; i -= 4) { |
| R3 = ((R3 << 11) | (R3 >>> 5)) & 0xffff; |
| R3 = (R3 - expandedKey[i - 1] - (R2 & R1) - (~R2 & R0)) & 0xffff; |
| |
| R2 = ((R2 << 13) | (R2 >>> 3)) & 0xffff; |
| R2 = (R2 - expandedKey[i - 2] - (R1 & R0) - (~R1 & R3)) & 0xffff; |
| |
| R1 = ((R1 << 14) | (R1 >>> 2)) & 0xffff; |
| R1 = (R1 - expandedKey[i - 3] - (R0 & R3) - (~R0 & R2)) & 0xffff; |
| |
| R0 = ((R0 << 15) | (R0 >>> 1)) & 0xffff; |
| R0 = (R0 - expandedKey[i - 4] - (R3 & R2) - (~R3 & R1)) & 0xffff; |
| } |
| |
| out[outOfs ] = (byte)R0; |
| out[outOfs + 1] = (byte)(R0 >> 8); |
| out[outOfs + 2] = (byte)R1; |
| out[outOfs + 3] = (byte)(R1 >> 8); |
| out[outOfs + 4] = (byte)R2; |
| out[outOfs + 5] = (byte)(R2 >> 8); |
| out[outOfs + 6] = (byte)R3; |
| out[outOfs + 7] = (byte)(R3 >> 8); |
| } |
| |
| } |
