net.freeutils.util.DES Maven / Gradle / Ivy
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/*
* Copyright © 2003-2024 Amichai Rothman
*
* This file is part of JElementary - the Java Elementary Utilities package.
*
* JElementary is free software: you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation, either version 2 of the License, or
* (at your option) any later version.
*
* JElementary 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 for more details.
*
* You should have received a copy of the GNU General Public License
* along with JElementary. If not, see
* This implementation is almost exactly that from "Applied Cryptography" by
* Bruce Schneier, with little adaptations to Java and local refactoring.
*/
public class DES {
private static final short[] bytebit = {
0200, 0100, 040, 020, 010, 04, 02, 01 // yes, it's octal
};
private static final int[] bigbyte = {
0x800000, 0x400000, 0x200000, 0x100000,
0x80000, 0x40000, 0x20000, 0x10000,
0x8000, 0x4000, 0x2000, 0x1000,
0x800, 0x400, 0x200, 0x100,
0x80, 0x40, 0x20, 0x10,
0x8, 0x4, 0x2, 0x1,
};
private static final byte[] pc1 = {
56, 48, 40, 32, 24, 16, 8, 0, 57, 49, 41, 33, 25, 17,
9, 1, 58, 50, 42, 34, 26, 18, 10, 2, 59, 51, 43, 35,
62, 54, 46, 38, 30, 22, 14, 6, 61, 53, 45, 37, 29, 21,
13, 5, 60, 52, 44, 36, 28, 20, 12, 4, 27, 19, 11, 3,
};
private static final byte[] totrot = {
1, 2, 4, 6, 8, 10, 12, 14, 15, 17, 19, 21, 23, 25, 27, 28
};
private static final byte[] pc2 = {
13, 16, 10, 23, 0, 4, 2, 27, 14, 5, 20, 9,
22, 18, 11, 3, 25, 7, 15, 6, 26, 19, 12, 1,
40, 51, 30, 36, 46, 54, 29, 39, 50, 44, 32, 47,
43, 48, 38, 55, 33, 52, 45, 41, 49, 35, 28, 31,
};
private static final int[] SP1 = {
0x01010400, 0x00000000, 0x00010000, 0x01010404,
0x01010004, 0x00010404, 0x00000004, 0x00010000,
0x00000400, 0x01010400, 0x01010404, 0x00000400,
0x01000404, 0x01010004, 0x01000000, 0x00000004,
0x00000404, 0x01000400, 0x01000400, 0x00010400,
0x00010400, 0x01010000, 0x01010000, 0x01000404,
0x00010004, 0x01000004, 0x01000004, 0x00010004,
0x00000000, 0x00000404, 0x00010404, 0x01000000,
0x00010000, 0x01010404, 0x00000004, 0x01010000,
0x01010400, 0x01000000, 0x01000000, 0x00000400,
0x01010004, 0x00010000, 0x00010400, 0x01000004,
0x00000400, 0x00000004, 0x01000404, 0x00010404,
0x01010404, 0x00010004, 0x01010000, 0x01000404,
0x01000004, 0x00000404, 0x00010404, 0x01010400,
0x00000404, 0x01000400, 0x01000400, 0x00000000,
0x00010004, 0x00010400, 0x00000000, 0x01010004,
};
private static final int[] SP2 = {
0x80108020, 0x80008000, 0x00008000, 0x00108020,
0x00100000, 0x00000020, 0x80100020, 0x80008020,
0x80000020, 0x80108020, 0x80108000, 0x80000000,
0x80008000, 0x00100000, 0x00000020, 0x80100020,
0x00108000, 0x00100020, 0x80008020, 0x00000000,
0x80000000, 0x00008000, 0x00108020, 0x80100000,
0x00100020, 0x80000020, 0x00000000, 0x00108000,
0x00008020, 0x80108000, 0x80100000, 0x00008020,
0x00000000, 0x00108020, 0x80100020, 0x00100000,
0x80008020, 0x80100000, 0x80108000, 0x00008000,
0x80100000, 0x80008000, 0x00000020, 0x80108020,
0x00108020, 0x00000020, 0x00008000, 0x80000000,
0x00008020, 0x80108000, 0x00100000, 0x80000020,
0x00100020, 0x80008020, 0x80000020, 0x00100020,
0x00108000, 0x00000000, 0x80008000, 0x00008020,
0x80000000, 0x80100020, 0x80108020, 0x00108000,
};
private static final int[] SP3 = {
0x00000208, 0x08020200, 0x00000000, 0x08020008,
0x08000200, 0x00000000, 0x00020208, 0x08000200,
0x00020008, 0x08000008, 0x08000008, 0x00020000,
0x08020208, 0x00020008, 0x08020000, 0x00000208,
0x08000000, 0x00000008, 0x08020200, 0x00000200,
0x00020200, 0x08020000, 0x08020008, 0x00020208,
0x08000208, 0x00020200, 0x00020000, 0x08000208,
0x00000008, 0x08020208, 0x00000200, 0x08000000,
0x08020200, 0x08000000, 0x00020008, 0x00000208,
0x00020000, 0x08020200, 0x08000200, 0x00000000,
0x00000200, 0x00020008, 0x08020208, 0x08000200,
0x08000008, 0x00000200, 0x00000000, 0x08020008,
0x08000208, 0x00020000, 0x08000000, 0x08020208,
0x00000008, 0x00020208, 0x00020200, 0x08000008,
0x08020000, 0x08000208, 0x00000208, 0x08020000,
0x00020208, 0x00000008, 0x08020008, 0x00020200,
};
private static final int[] SP4 = {
0x00802001, 0x00002081, 0x00002081, 0x00000080,
0x00802080, 0x00800081, 0x00800001, 0x00002001,
0x00000000, 0x00802000, 0x00802000, 0x00802081,
0x00000081, 0x00000000, 0x00800080, 0x00800001,
0x00000001, 0x00002000, 0x00800000, 0x00802001,
0x00000080, 0x00800000, 0x00002001, 0x00002080,
0x00800081, 0x00000001, 0x00002080, 0x00800080,
0x00002000, 0x00802080, 0x00802081, 0x00000081,
0x00800080, 0x00800001, 0x00802000, 0x00802081,
0x00000081, 0x00000000, 0x00000000, 0x00802000,
0x00002080, 0x00800080, 0x00800081, 0x00000001,
0x00802001, 0x00002081, 0x00002081, 0x00000080,
0x00802081, 0x00000081, 0x00000001, 0x00002000,
0x00800001, 0x00002001, 0x00802080, 0x00800081,
0x00002001, 0x00002080, 0x00800000, 0x00802001,
0x00000080, 0x00800000, 0x00002000, 0x00802080,
};
private static final int[] SP5 = {
0x00000100, 0x02080100, 0x02080000, 0x42000100,
0x00080000, 0x00000100, 0x40000000, 0x02080000,
0x40080100, 0x00080000, 0x02000100, 0x40080100,
0x42000100, 0x42080000, 0x00080100, 0x40000000,
0x02000000, 0x40080000, 0x40080000, 0x00000000,
0x40000100, 0x42080100, 0x42080100, 0x02000100,
0x42080000, 0x40000100, 0x00000000, 0x42000000,
0x02080100, 0x02000000, 0x42000000, 0x00080100,
0x00080000, 0x42000100, 0x00000100, 0x02000000,
0x40000000, 0x02080000, 0x42000100, 0x40080100,
0x02000100, 0x40000000, 0x42080000, 0x02080100,
0x40080100, 0x00000100, 0x02000000, 0x42080000,
0x42080100, 0x00080100, 0x42000000, 0x42080100,
0x02080000, 0x00000000, 0x40080000, 0x42000000,
0x00080100, 0x02000100, 0x40000100, 0x00080000,
0x00000000, 0x40080000, 0x02080100, 0x40000100,
};
private static final int[] SP6 = {
0x20000010, 0x20400000, 0x00004000, 0x20404010,
0x20400000, 0x00000010, 0x20404010, 0x00400000,
0x20004000, 0x00404010, 0x00400000, 0x20000010,
0x00400010, 0x20004000, 0x20000000, 0x00004010,
0x00000000, 0x00400010, 0x20004010, 0x00004000,
0x00404000, 0x20004010, 0x00000010, 0x20400010,
0x20400010, 0x00000000, 0x00404010, 0x20404000,
0x00004010, 0x00404000, 0x20404000, 0x20000000,
0x20004000, 0x00000010, 0x20400010, 0x00404000,
0x20404010, 0x00400000, 0x00004010, 0x20000010,
0x00400000, 0x20004000, 0x20000000, 0x00004010,
0x20000010, 0x20404010, 0x00404000, 0x20400000,
0x00404010, 0x20404000, 0x00000000, 0x20400010,
0x00000010, 0x00004000, 0x20400000, 0x00404010,
0x00004000, 0x00400010, 0x20004010, 0x00000000,
0x20404000, 0x20000000, 0x00400010, 0x20004010,
};
private static final int[] SP7 = {
0x00200000, 0x04200002, 0x04000802, 0x00000000,
0x00000800, 0x04000802, 0x00200802, 0x04200800,
0x04200802, 0x00200000, 0x00000000, 0x04000002,
0x00000002, 0x04000000, 0x04200002, 0x00000802,
0x04000800, 0x00200802, 0x00200002, 0x04000800,
0x04000002, 0x04200000, 0x04200800, 0x00200002,
0x04200000, 0x00000800, 0x00000802, 0x04200802,
0x00200800, 0x00000002, 0x04000000, 0x00200800,
0x04000000, 0x00200800, 0x00200000, 0x04000802,
0x04000802, 0x04200002, 0x04200002, 0x00000002,
0x00200002, 0x04000000, 0x04000800, 0x00200000,
0x04200800, 0x00000802, 0x00200802, 0x04200800,
0x00000802, 0x04000002, 0x04200802, 0x04200000,
0x00200800, 0x00000000, 0x00000002, 0x04200802,
0x00000000, 0x00200802, 0x04200000, 0x00000800,
0x04000002, 0x04000800, 0x00000800, 0x00200002,
};
private static final int[] SP8 = {
0x10001040, 0x00001000, 0x00040000, 0x10041040,
0x10000000, 0x10001040, 0x00000040, 0x10000000,
0x00040040, 0x10040000, 0x10041040, 0x00041000,
0x10041000, 0x00041040, 0x00001000, 0x00000040,
0x10040000, 0x10000040, 0x10001000, 0x00001040,
0x00041000, 0x00040040, 0x10040040, 0x10041000,
0x00001040, 0x00000000, 0x00000000, 0x10040040,
0x10000040, 0x10001000, 0x00041040, 0x00040000,
0x00041040, 0x00040000, 0x10041000, 0x00001000,
0x00000040, 0x10040040, 0x00001000, 0x00041040,
0x10001000, 0x00000040, 0x10000040, 0x10040000,
0x10040040, 0x10000000, 0x00040000, 0x10001040,
0x00000000, 0x10041040, 0x00040040, 0x10000040,
0x10040000, 0x10001000, 0x10001040, 0x00000000,
0x10041040, 0x00041000, 0x00041000, 0x00001040,
0x00001040, 0x00040040, 0x10000000, 0x10041000,
};
private int[] keys;
/**
* Constructs a DES engine.
*
* @param encryption true to perform encryption,
* or false to perform decryption
* @param key the encryption key
*/
public DES(boolean encryption, byte[] key) {
if (key.length != 8)
throw new IllegalArgumentException("key must be exactly 8 bytes long");
this.keys = deskey(encryption, key);
}
/**
* Perform the DES function on a single data block (8 bytes).
*
* @param src an array containing the source data
* @param srcPos the start position of the source data within the array
* @param dest an array which is the destination for processed data
* @param destPos the start position of the destination data within the array
*/
public void process(byte[] src, int srcPos, byte[] dest, int destPos) {
desfunc(keys, src, srcPos, dest, destPos);
}
/**
* Generates the key schedule for encryption/decryption (they are the same
* keys but in reverse order).
*
* Schneier's attribution: Thanks to James Gillogly & Phil Karn!
*
* @param encryption true for encryption, false for decryption
* @param key the encryption key
* @return the key schedule
*/
private int[] deskey(boolean encryption, byte[] key) {
boolean[] pc1m = new boolean[56];
boolean[] pcr = new boolean[56];
int[] kn = new int[32];
for (int j = 0; j < 56; j++) {
int l = pc1[j];
pc1m[j] = ((key[l >>> 3] & bytebit[l & 7]) != 0);
}
for (int i = 0; i < 16; i++) {
int m = (encryption ? i : 15 - i) << 1;
int n = m + 1;
byte t = totrot[i];
for (int j = 0; j < 28; j++) {
int l = j + t;
pcr[j] = pc1m[l < 28 ? l : l - 28];
}
for (int j = 28; j < 56; j++) {
int l = j + t;
pcr[j] = pc1m[l < 56 ? l : l - 28];
}
for (int j = 0; j < 24; j++) {
if (pcr[pc2[j]])
kn[m] |= bigbyte[j];
if (pcr[pc2[j + 24]])
kn[n] |= bigbyte[j];
}
}
// cookey inlined
for (int i = 0; i < 32; i += 2) {
int raw0 = kn[i];
int raw1 = kn[i + 1];
kn[i] = ((raw0 & 0x00fc0000) << 6) | ((raw0 & 0x00000fc0) << 10)
| ((raw1 & 0x00fc0000) >>> 10) | ((raw1 & 0x00000fc0) >>> 6);
kn[i + 1] = ((raw0 & 0x0003f000) << 12) | ((raw0 & 0x0000003f) << 16)
| ((raw1 & 0x0003f000) >>> 4) | (raw1 & 0x0000003f);
}
return kn;
}
/**
* Perform the DES function on a single data block (8 bytes).
*
* @param key the key schedule
* @param src an array containing the source data
* @param srcPos the start position of the source data within the array
* @param dest an array which is the destination for processed data
* @param destPos the start position of the destination data within the array
*/
private void desfunc(int[] key, byte[] src, int srcPos, byte[] dest, int destPos) {
int work, right, left;
left = (src[srcPos] & 0xff) << 24;
left |= (src[srcPos + 1] & 0xff) << 16;
left |= (src[srcPos + 2] & 0xff) << 8;
left |= (src[srcPos + 3] & 0xff);
right = (src[srcPos + 4] & 0xff) << 24;
right |= (src[srcPos + 5] & 0xff) << 16;
right |= (src[srcPos + 6] & 0xff) << 8;
right |= (src[srcPos + 7] & 0xff);
work = ((left >>> 4) ^ right) & 0x0f0f0f0f;
right ^= work;
left ^= (work << 4);
work = ((left >>> 16) ^ right) & 0x0000ffff;
right ^= work;
left ^= (work << 16);
work = ((right >>> 2) ^ left) & 0x33333333;
left ^= work;
right ^= (work << 2);
work = ((right >>> 8) ^ left) & 0x00ff00ff;
left ^= work;
right ^= (work << 8);
right = right << 1 | right >>> 31 & 1;
work = (left ^ right) & 0xaaaaaaaa;
left ^= work;
right ^= work;
left = left << 1 | left >>> 31 & 1;
for (int round = 0; round < 32; round += 4) {
int fval;
work = (right << 28) | (right >>> 4);
work ^= key[round];
fval = SP7[ work & 0x3f]
| SP5[(work >>> 8) & 0x3f]
| SP3[(work >>> 16) & 0x3f]
| SP1[(work >>> 24) & 0x3f];
work = right ^ key[round + 1];
fval |= SP8[ work & 0x3f]
| SP6[(work >>> 8) & 0x3f]
| SP4[(work >>> 16) & 0x3f]
| SP2[(work >>> 24) & 0x3f];
left ^= fval;
work = (left << 28) | (left >>> 4);
work ^= key[round + 2];
fval = SP7[ work & 0x3f]
| SP5[(work >>> 8) & 0x3f]
| SP3[(work >>> 16) & 0x3f]
| SP1[(work >>> 24) & 0x3f];
work = left ^ key[round + 3];
fval |= SP8[ work & 0x3f]
| SP6[(work >>> 8) & 0x3f]
| SP4[(work >>> 16) & 0x3f]
| SP2[(work >>> 24) & 0x3f];
right ^= fval;
}
right = (right << 31) | (right >>> 1);
work = (left ^ right) & 0xaaaaaaaa;
left ^= work;
right ^= work;
left = (left << 31) | (left >>> 1);
work = ((left >>> 8) ^ right) & 0x00ff00ff;
right ^= work;
left ^= (work << 8);
work = ((left >>> 2) ^ right) & 0x33333333;
right ^= work;
left ^= (work << 2);
work = ((right >>> 16) ^ left) & 0x0000ffff;
left ^= work;
right ^= (work << 16);
work = ((right >>> 4) ^ left) & 0x0f0f0f0f;
left ^= work;
right ^= (work << 4);
dest[destPos] = (byte)((right >> 24) & 0xff);
dest[destPos + 1] = (byte)((right >> 16) & 0xff);
dest[destPos + 2] = (byte)((right >> 8) & 0xff);
dest[destPos + 3] = (byte)(right & 0xff);
dest[destPos + 4] = (byte)((left >> 24) & 0xff);
dest[destPos + 5] = (byte)((left >> 16) & 0xff);
dest[destPos + 6] = (byte)((left >> 8) & 0xff);
dest[destPos + 7] = (byte)(left & 0xff);
}
}