Java tutorial
/* * @(#)UnixCrypt.java 0.9 96/11/25 * * Copyright (c) 1996 Aki Yoshida. All rights reserved. * * Permission to use, copy, modify and distribute this software * for non-commercial or commercial purposes and without fee is * hereby granted provided that this copyright notice appears in * all copies. */ /** * Unix crypt(3C) utility * * @version 0.9, 11/25/96 * @author Aki Yoshida */ /** * modified April 2001 * by Iris Van den Broeke, Daniel Deville */ /* ------------------------------------------------------------ */ /** Unix Crypt. * Implements the one way cryptography used by Unix systems for * simple password protection. * @version $Id: UnixCrypt.java,v 1.5 2004/10/11 00:28:41 gregwilkins Exp $ * @author Greg Wilkins (gregw) */ public class UnixCrypt extends Object { /* (mostly) Standard DES Tables from Tom Truscott */ private static final byte[] IP = { /* initial permutation */ 58, 50, 42, 34, 26, 18, 10, 2, 60, 52, 44, 36, 28, 20, 12, 4, 62, 54, 46, 38, 30, 22, 14, 6, 64, 56, 48, 40, 32, 24, 16, 8, 57, 49, 41, 33, 25, 17, 9, 1, 59, 51, 43, 35, 27, 19, 11, 3, 61, 53, 45, 37, 29, 21, 13, 5, 63, 55, 47, 39, 31, 23, 15, 7 }; /* The final permutation is the inverse of IP - no table is necessary */ private static final byte[] ExpandTr = { /* expansion operation */ 32, 1, 2, 3, 4, 5, 4, 5, 6, 7, 8, 9, 8, 9, 10, 11, 12, 13, 12, 13, 14, 15, 16, 17, 16, 17, 18, 19, 20, 21, 20, 21, 22, 23, 24, 25, 24, 25, 26, 27, 28, 29, 28, 29, 30, 31, 32, 1 }; private static final byte[] PC1 = { /* permuted choice table 1 */ 57, 49, 41, 33, 25, 17, 9, 1, 58, 50, 42, 34, 26, 18, 10, 2, 59, 51, 43, 35, 27, 19, 11, 3, 60, 52, 44, 36, 63, 55, 47, 39, 31, 23, 15, 7, 62, 54, 46, 38, 30, 22, 14, 6, 61, 53, 45, 37, 29, 21, 13, 5, 28, 20, 12, 4 }; private static final byte[] Rotates = { /* PC1 rotation schedule */ 1, 1, 2, 2, 2, 2, 2, 2, 1, 2, 2, 2, 2, 2, 2, 1 }; private static final byte[] PC2 = { /* permuted choice table 2 */ 9, 18, 14, 17, 11, 24, 1, 5, 22, 25, 3, 28, 15, 6, 21, 10, 35, 38, 23, 19, 12, 4, 26, 8, 43, 54, 16, 7, 27, 20, 13, 2, 0, 0, 41, 52, 31, 37, 47, 55, 0, 0, 30, 40, 51, 45, 33, 48, 0, 0, 44, 49, 39, 56, 34, 53, 0, 0, 46, 42, 50, 36, 29, 32 }; private static final byte[][] S = { /* 48->32 bit substitution tables */ /* S[1] */ { 14, 4, 13, 1, 2, 15, 11, 8, 3, 10, 6, 12, 5, 9, 0, 7, 0, 15, 7, 4, 14, 2, 13, 1, 10, 6, 12, 11, 9, 5, 3, 8, 4, 1, 14, 8, 13, 6, 2, 11, 15, 12, 9, 7, 3, 10, 5, 0, 15, 12, 8, 2, 4, 9, 1, 7, 5, 11, 3, 14, 10, 0, 6, 13 }, /* S[2] */ { 15, 1, 8, 14, 6, 11, 3, 4, 9, 7, 2, 13, 12, 0, 5, 10, 3, 13, 4, 7, 15, 2, 8, 14, 12, 0, 1, 10, 6, 9, 11, 5, 0, 14, 7, 11, 10, 4, 13, 1, 5, 8, 12, 6, 9, 3, 2, 15, 13, 8, 10, 1, 3, 15, 4, 2, 11, 6, 7, 12, 0, 5, 14, 9 }, /* S[3] */ { 10, 0, 9, 14, 6, 3, 15, 5, 1, 13, 12, 7, 11, 4, 2, 8, 13, 7, 0, 9, 3, 4, 6, 10, 2, 8, 5, 14, 12, 11, 15, 1, 13, 6, 4, 9, 8, 15, 3, 0, 11, 1, 2, 12, 5, 10, 14, 7, 1, 10, 13, 0, 6, 9, 8, 7, 4, 15, 14, 3, 11, 5, 2, 12 }, /* S[4] */ { 7, 13, 14, 3, 0, 6, 9, 10, 1, 2, 8, 5, 11, 12, 4, 15, 13, 8, 11, 5, 6, 15, 0, 3, 4, 7, 2, 12, 1, 10, 14, 9, 10, 6, 9, 0, 12, 11, 7, 13, 15, 1, 3, 14, 5, 2, 8, 4, 3, 15, 0, 6, 10, 1, 13, 8, 9, 4, 5, 11, 12, 7, 2, 14 }, /* S[5] */ { 2, 12, 4, 1, 7, 10, 11, 6, 8, 5, 3, 15, 13, 0, 14, 9, 14, 11, 2, 12, 4, 7, 13, 1, 5, 0, 15, 10, 3, 9, 8, 6, 4, 2, 1, 11, 10, 13, 7, 8, 15, 9, 12, 5, 6, 3, 0, 14, 11, 8, 12, 7, 1, 14, 2, 13, 6, 15, 0, 9, 10, 4, 5, 3 }, /* S[6] */ { 12, 1, 10, 15, 9, 2, 6, 8, 0, 13, 3, 4, 14, 7, 5, 11, 10, 15, 4, 2, 7, 12, 9, 5, 6, 1, 13, 14, 0, 11, 3, 8, 9, 14, 15, 5, 2, 8, 12, 3, 7, 0, 4, 10, 1, 13, 11, 6, 4, 3, 2, 12, 9, 5, 15, 10, 11, 14, 1, 7, 6, 0, 8, 13 }, /* S[7] */ { 4, 11, 2, 14, 15, 0, 8, 13, 3, 12, 9, 7, 5, 10, 6, 1, 13, 0, 11, 7, 4, 9, 1, 10, 14, 3, 5, 12, 2, 15, 8, 6, 1, 4, 11, 13, 12, 3, 7, 14, 10, 15, 6, 8, 0, 5, 9, 2, 6, 11, 13, 8, 1, 4, 10, 7, 9, 5, 0, 15, 14, 2, 3, 12 }, /* S[8] */ { 13, 2, 8, 4, 6, 15, 11, 1, 10, 9, 3, 14, 5, 0, 12, 7, 1, 15, 13, 8, 10, 3, 7, 4, 12, 5, 6, 11, 0, 14, 9, 2, 7, 11, 4, 1, 9, 12, 14, 2, 0, 6, 10, 13, 15, 3, 5, 8, 2, 1, 14, 7, 4, 10, 8, 13, 15, 12, 9, 0, 3, 5, 6, 11 } }; private static final byte[] P32Tr = { /* 32-bit permutation function */ 16, 7, 20, 21, 29, 12, 28, 17, 1, 15, 23, 26, 5, 18, 31, 10, 2, 8, 24, 14, 32, 27, 3, 9, 19, 13, 30, 6, 22, 11, 4, 25 }; private static final byte[] CIFP = { /* compressed/interleaved permutation */ 1, 2, 3, 4, 17, 18, 19, 20, 5, 6, 7, 8, 21, 22, 23, 24, 9, 10, 11, 12, 25, 26, 27, 28, 13, 14, 15, 16, 29, 30, 31, 32, 33, 34, 35, 36, 49, 50, 51, 52, 37, 38, 39, 40, 53, 54, 55, 56, 41, 42, 43, 44, 57, 58, 59, 60, 45, 46, 47, 48, 61, 62, 63, 64 }; private static final byte[] ITOA64 = { /* 0..63 => ascii-64 */ (byte) '.', (byte) '/', (byte) '0', (byte) '1', (byte) '2', (byte) '3', (byte) '4', (byte) '5', (byte) '6', (byte) '7', (byte) '8', (byte) '9', (byte) 'A', (byte) 'B', (byte) 'C', (byte) 'D', (byte) 'E', (byte) 'F', (byte) 'G', (byte) 'H', (byte) 'I', (byte) 'J', (byte) 'K', (byte) 'L', (byte) 'M', (byte) 'N', (byte) 'O', (byte) 'P', (byte) 'Q', (byte) 'R', (byte) 'S', (byte) 'T', (byte) 'U', (byte) 'V', (byte) 'W', (byte) 'X', (byte) 'Y', (byte) 'Z', (byte) 'a', (byte) 'b', (byte) 'c', (byte) 'd', (byte) 'e', (byte) 'f', (byte) 'g', (byte) 'h', (byte) 'i', (byte) 'j', (byte) 'k', (byte) 'l', (byte) 'm', (byte) 'n', (byte) 'o', (byte) 'p', (byte) 'q', (byte) 'r', (byte) 's', (byte) 't', (byte) 'u', (byte) 'v', (byte) 'w', (byte) 'x', (byte) 'y', (byte) 'z' }; /* Tables that are initialized at run time */ private static byte[] A64TOI = new byte[128]; /* ascii-64 => 0..63 */ /* Initial key schedule permutation */ private static long[][] PC1ROT = new long[16][16]; /* Subsequent key schedule rotation permutations */ private static long[][][] PC2ROT = new long[2][16][16]; /* Initial permutation/expansion table */ private static long[][] IE3264 = new long[8][16]; /* Table that combines the S, P, and E operations. */ private static long[][] SPE = new long[8][64]; /* compressed/interleaved => final permutation table */ private static long[][] CF6464 = new long[16][16]; /* */ static { byte[] perm = new byte[64]; byte[] temp = new byte[64]; // inverse table. for (int i = 0; i < 64; i++) A64TOI[ITOA64[i]] = (byte) i; // PC1ROT - bit reverse, then PC1, then Rotate, then PC2 for (int i = 0; i < 64; i++) perm[i] = (byte) 0; ; for (int i = 0; i < 64; i++) { int k; if ((k = (int) PC2[i]) == 0) continue; k += Rotates[0] - 1; if ((k % 28) < Rotates[0]) k -= 28; k = (int) PC1[k]; if (k > 0) { k--; k = (k | 0x07) - (k & 0x07); k++; } perm[i] = (byte) k; } init_perm(PC1ROT, perm, 8); // PC2ROT - PC2 inverse, then Rotate, then PC2 for (int j = 0; j < 2; j++) { int k; for (int i = 0; i < 64; i++) perm[i] = temp[i] = 0; for (int i = 0; i < 64; i++) { if ((k = (int) PC2[i]) == 0) continue; temp[k - 1] = (byte) (i + 1); } for (int i = 0; i < 64; i++) { if ((k = (int) PC2[i]) == 0) continue; k += j; if ((k % 28) <= j) k -= 28; perm[i] = temp[k]; } init_perm(PC2ROT[j], perm, 8); } // Bit reverse, intial permupation, expantion for (int i = 0; i < 8; i++) { for (int j = 0; j < 8; j++) { int k = (j < 2) ? 0 : IP[ExpandTr[i * 6 + j - 2] - 1]; if (k > 32) k -= 32; else if (k > 0) k--; if (k > 0) { k--; k = (k | 0x07) - (k & 0x07); k++; } perm[i * 8 + j] = (byte) k; } } init_perm(IE3264, perm, 8); // Compression, final permutation, bit reverse for (int i = 0; i < 64; i++) { int k = IP[CIFP[i] - 1]; if (k > 0) { k--; k = (k | 0x07) - (k & 0x07); k++; } perm[k - 1] = (byte) (i + 1); } init_perm(CF6464, perm, 8); // SPE table for (int i = 0; i < 48; i++) perm[i] = P32Tr[ExpandTr[i] - 1]; for (int t = 0; t < 8; t++) { for (int j = 0; j < 64; j++) { int k = (((j >> 0) & 0x01) << 5) | (((j >> 1) & 0x01) << 3) | (((j >> 2) & 0x01) << 2) | (((j >> 3) & 0x01) << 1) | (((j >> 4) & 0x01) << 0) | (((j >> 5) & 0x01) << 4); k = S[t][k]; k = (((k >> 3) & 0x01) << 0) | (((k >> 2) & 0x01) << 1) | (((k >> 1) & 0x01) << 2) | (((k >> 0) & 0x01) << 3); for (int i = 0; i < 32; i++) temp[i] = 0; for (int i = 0; i < 4; i++) temp[4 * t + i] = (byte) ((k >> i) & 0x01); long kk = 0; for (int i = 24; --i >= 0;) kk = ((kk << 1) | ((long) temp[perm[i] - 1]) << 32 | ((long) temp[perm[i + 24] - 1])); SPE[t][j] = to_six_bit(kk); } } } /** * You can't call the constructer. */ private UnixCrypt() { } /** * Returns the transposed and split code of a 24-bit code * into a 4-byte code, each having 6 bits. */ private static int to_six_bit(int num) { return (((num << 26) & 0xfc000000) | ((num << 12) & 0xfc0000) | ((num >> 2) & 0xfc00) | ((num >> 16) & 0xfc)); } /** * Returns the transposed and split code of two 24-bit code * into two 4-byte code, each having 6 bits. */ private static long to_six_bit(long num) { return (((num << 26) & 0xfc000000fc000000L) | ((num << 12) & 0xfc000000fc0000L) | ((num >> 2) & 0xfc000000fc00L) | ((num >> 16) & 0xfc000000fcL)); } /** * Returns the permutation of the given 64-bit code with * the specified permutataion table. */ private static long perm6464(long c, long[][] p) { long out = 0L; for (int i = 8; --i >= 0;) { int t = (int) (0x00ff & c); c >>= 8; long tp = p[i << 1][t & 0x0f]; out |= tp; tp = p[(i << 1) + 1][t >> 4]; out |= tp; } return out; } /** * Returns the permutation of the given 32-bit code with * the specified permutataion table. */ private static long perm3264(int c, long[][] p) { long out = 0L; for (int i = 4; --i >= 0;) { int t = (0x00ff & c); c >>= 8; long tp = p[i << 1][t & 0x0f]; out |= tp; tp = p[(i << 1) + 1][t >> 4]; out |= tp; } return out; } /** * Returns the key schedule for the given key. */ private static long[] des_setkey(long keyword) { long K = perm6464(keyword, PC1ROT); long[] KS = new long[16]; KS[0] = K & ~0x0303030300000000L; for (int i = 1; i < 16; i++) { KS[i] = K; K = perm6464(K, PC2ROT[Rotates[i] - 1]); KS[i] = K & ~0x0303030300000000L; } return KS; } /** * Returns the DES encrypted code of the given word with the specified * environment. */ private static long des_cipher(long in, int salt, int num_iter, long[] KS) { salt = to_six_bit(salt); long L = in; long R = L; L &= 0x5555555555555555L; R = (R & 0xaaaaaaaa00000000L) | ((R >> 1) & 0x0000000055555555L); L = ((((L << 1) | (L << 32)) & 0xffffffff00000000L) | ((R | (R >> 32)) & 0x00000000ffffffffL)); L = perm3264((int) (L >> 32), IE3264); R = perm3264((int) (L & 0xffffffff), IE3264); while (--num_iter >= 0) { for (int loop_count = 0; loop_count < 8; loop_count++) { long kp; long B; long k; kp = KS[(loop_count << 1)]; k = ((R >> 32) ^ R) & salt & 0xffffffffL; k |= (k << 32); B = (k ^ R ^ kp); L ^= (SPE[0][(int) ((B >> 58) & 0x3f)] ^ SPE[1][(int) ((B >> 50) & 0x3f)] ^ SPE[2][(int) ((B >> 42) & 0x3f)] ^ SPE[3][(int) ((B >> 34) & 0x3f)] ^ SPE[4][(int) ((B >> 26) & 0x3f)] ^ SPE[5][(int) ((B >> 18) & 0x3f)] ^ SPE[6][(int) ((B >> 10) & 0x3f)] ^ SPE[7][(int) ((B >> 2) & 0x3f)]); kp = KS[(loop_count << 1) + 1]; k = ((L >> 32) ^ L) & salt & 0xffffffffL; k |= (k << 32); B = (k ^ L ^ kp); R ^= (SPE[0][(int) ((B >> 58) & 0x3f)] ^ SPE[1][(int) ((B >> 50) & 0x3f)] ^ SPE[2][(int) ((B >> 42) & 0x3f)] ^ SPE[3][(int) ((B >> 34) & 0x3f)] ^ SPE[4][(int) ((B >> 26) & 0x3f)] ^ SPE[5][(int) ((B >> 18) & 0x3f)] ^ SPE[6][(int) ((B >> 10) & 0x3f)] ^ SPE[7][(int) ((B >> 2) & 0x3f)]); } // swap L and R L ^= R; R ^= L; L ^= R; } L = ((((L >> 35) & 0x0f0f0f0fL) | (((L & 0xffffffff) << 1) & 0xf0f0f0f0L)) << 32 | (((R >> 35) & 0x0f0f0f0fL) | (((R & 0xffffffff) << 1) & 0xf0f0f0f0L))); L = perm6464(L, CF6464); return L; } /** * Initializes the given permutation table with the mapping table. */ private static void init_perm(long[][] perm, byte[] p, int chars_out) { for (int k = 0; k < chars_out * 8; k++) { int l = p[k] - 1; if (l < 0) continue; int i = l >> 2; l = 1 << (l & 0x03); for (int j = 0; j < 16; j++) { int s = ((k & 0x07) + ((7 - (k >> 3)) << 3)); if ((j & l) != 0x00) perm[i][j] |= (1L << s); } } } /** * Encrypts String into crypt (Unix) code. * @param key the key to be encrypted * @param setting the salt to be used * @return the encrypted String */ public static String crypt(String key, String setting) { long constdatablock = 0L; /* encryption constant */ byte[] cryptresult = new byte[13]; /* encrypted result */ long keyword = 0L; /* invalid parameters! */ if (key == null || setting == null) return "*"; // will NOT match under ANY circumstances! int keylen = key.length(); for (int i = 0; i < 8; i++) { keyword = (keyword << 8) | ((i < keylen) ? 2 * key.charAt(i) : 0); } long[] KS = des_setkey(keyword); int salt = 0; for (int i = 2; --i >= 0;) { char c = (i < setting.length()) ? setting.charAt(i) : '.'; cryptresult[i] = (byte) c; salt = (salt << 6) | (0x00ff & A64TOI[c]); } long rsltblock = des_cipher(constdatablock, salt, 25, KS); cryptresult[12] = ITOA64[(((int) rsltblock) << 2) & 0x3f]; rsltblock >>= 4; for (int i = 12; --i >= 2;) { cryptresult[i] = ITOA64[((int) rsltblock) & 0x3f]; rsltblock >>= 6; } return new String(cryptresult, 0x00, 0, 13); } public static void main(String[] arg) { if (arg.length != 2) { System.err.println("Usage - java org.mortbay.util.UnixCrypt <key> <salt>"); System.exit(1); } System.err.println("Crypt=" + crypt(arg[0], arg[1])); } }