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diff --git a/src/desCalculator/des.c b/src/desCalculator/des.c
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+
+/* Sofware DES functions
+ * written 12 Dec 1986 by Phil Karn, KA9Q; large sections adapted from
+ * the 1977 public-domain program by Jim Gillogly
+ * Modified for additional speed - 6 December 1988 Phil Karn
+ * Modified for parameterized key schedules - Jan 1991 Phil Karn
+ * Callers now allocate a key schedule as follows:
+ * kn = (char (*)[8])malloc(sizeof(char) * 8 * 16);
+ * or
+ * char kn[16][8];
+ */
+
+/* modified in order to use the libmcrypt API by Nikos Mavroyanopoulos
+ * All modifications are placed under the license of libmcrypt.
+ */
+
+/* $Id: des.c,v 1.13 2003/01/19 17:48:27 nmav Exp $ */
+
+#include "des.h"
+
+/* #define NULL 0 */
+
+static void permute_ip(), permute_fp(), perminit_ip(), spinit(),
+perminit_fp();
+static uint32_t f();
+
+
+/* Tables defined in the Data Encryption Standard documents */
+
+/* initial permutation IP */
+static char ip[] = {
+ 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
+};
+
+/* final permutation IP^-1 */
+static char fp[] = {
+ 40, 8, 48, 16, 56, 24, 64, 32,
+ 39, 7, 47, 15, 55, 23, 63, 31,
+ 38, 6, 46, 14, 54, 22, 62, 30,
+ 37, 5, 45, 13, 53, 21, 61, 29,
+ 36, 4, 44, 12, 52, 20, 60, 28,
+ 35, 3, 43, 11, 51, 19, 59, 27,
+ 34, 2, 42, 10, 50, 18, 58, 26,
+ 33, 1, 41, 9, 49, 17, 57, 25
+};
+
+/* expansion operation matrix
+ * This is for reference only; it is unused in the code
+ * as the f() function performs it implicitly for speed
+ */
+#ifdef notdef
+static char ei[] = {
+ 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
+};
+#endif
+
+/* permuted choice table (key) */
+static char pc1[] = {
+ 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
+};
+
+/* number left rotations of pc1 */
+static char totrot[] = {
+ 1, 2, 4, 6, 8, 10, 12, 14, 15, 17, 19, 21, 23, 25, 27, 28
+};
+
+/* permuted choice key (table) */
+static char pc2[] = {
+ 14, 17, 11, 24, 1, 5,
+ 3, 28, 15, 6, 21, 10,
+ 23, 19, 12, 4, 26, 8,
+ 16, 7, 27, 20, 13, 2,
+ 41, 52, 31, 37, 47, 55,
+ 30, 40, 51, 45, 33, 48,
+ 44, 49, 39, 56, 34, 53,
+ 46, 42, 50, 36, 29, 32
+};
+
+/* The (in)famous S-boxes */
+static char si[8][64] = {
+ /* S1 */
+ {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},
+
+ /* S2 */
+ {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},
+
+ /* S3 */
+ {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},
+
+ /* S4 */
+ {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},
+
+ /* S5 */
+ {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},
+
+ /* S6 */
+ {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},
+
+ /* S7 */
+ {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},
+
+ /* S8 */
+ {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},
+
+};
+
+/* 32-bit permutation function P used on the output of the S-boxes */
+static char p32i[] = {
+ 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
+};
+
+/* End of DES-defined tables */
+
+/* Lookup tables initialized once only at startup by desinit() */
+
+/* bit 0 is left-most in byte */
+static int bytebit[] = {
+ 0200, 0100, 040, 020, 010, 04, 02, 01
+};
+
+static int nibblebit[] = {
+ 010, 04, 02, 01
+};
+
+/* Allocate space and initialize DES lookup arrays
+ * mode == 0: standard Data Encryption Algorithm
+ */
+static int _mcrypt_desinit(DES_KEY * key)
+{
+
+ spinit(key);
+ perminit_ip(key);
+ perminit_fp(key);
+
+ return 0;
+}
+
+
+/* Set key (initialize key schedule array) */
+int _mcrypt_set_key(DES_KEY * dkey, char *user_key, int len)
+{
+ char pc1m[56]; /* place to modify pc1 into */
+ char pcr[56]; /* place to rotate pc1 into */
+ register int i, j, l;
+ int m;
+
+ Bzero(dkey, sizeof(DES_KEY));
+ _mcrypt_desinit(dkey);
+
+ /* Clear key schedule */
+
+
+ for (j = 0; j < 56; j++) { /* convert pc1 to bits of key */
+ l = pc1[j] - 1; /* integer bit location */
+ m = l & 07; /* find bit */
+ pc1m[j] = (user_key[l >> 3] & /* find which key byte l is in */
+ bytebit[m]) /* and which bit of that byte */
+ ? 1 : 0; /* and store 1-bit result */
+
+ }
+ for (i = 0; i < 16; i++) { /* key chunk for each iteration */
+ for (j = 0; j < 56; j++) /* rotate pc1 the right amount */
+ pcr[j] =
+ pc1m[(l = j + totrot[i]) <
+ (j < 28 ? 28 : 56) ? l : l - 28];
+ /* rotate left and right halves independently */
+ for (j = 0; j < 48; j++) { /* select bits individually */
+ /* check bit that goes to kn[j] */
+ if (pcr[pc2[j] - 1]) {
+ /* mask it in if it's there */
+ l = j % 6;
+ dkey->kn[i][j / 6] |= bytebit[l] >> 2;
+ }
+ }
+ }
+ return 0;
+}
+
+/* In-place encryption of 64-bit block */
+void _mcrypt_encrypt(DES_KEY * key, char *block)
+{
+ uint32_t strings[20];
+
+ register uint32_t left, right;
+ register char *knp;
+ uint32_t work[2]; /* Working data storage */
+
+ strings[0] = 0x8080CAA3;
+ permute_ip(block, key, (char *) work); /* Initial Permutation */
+#ifndef WORDS_BIGENDIAN
+ left = byteswap32(work[0]);
+ right = byteswap32(work[1]);
+#else
+ left = work[0];
+ right = work[1];
+#endif
+
+ strings[1] = 0x83F5EF93;
+ /* Do the 16 rounds.
+ * The rounds are numbered from 0 to 15. On even rounds
+ * the right half is fed to f() and the result exclusive-ORs
+ * the left half; on odd rounds the reverse is done.
+ */
+ knp = &key->kn[0][0];
+ strings[3] = 0xF5C58BFF;
+ left ^= f(key, right, knp);
+ knp += 8;
+ strings[2] = 0xE5EF9A9C;
+ right ^= f(key, left, knp);
+ printf("des_intermediate_value = [0x%X, 0x%X]\n", left, right);
+ knp += 8;
+ left ^= f(key, right, knp);
+ knp += 8;
+ right ^= f(key, left, knp);
+ knp += 8;
+ left ^= f(key, right, knp);
+ knp += 8;
+ right ^= f(key, left, knp);
+ knp += 8;
+ left ^= f(key, right, knp);
+ knp += 8;
+ right ^= f(key, left, knp);
+ knp += 8;
+ left ^= f(key, right, knp);
+ knp += 8;
+ right ^= f(key, left, knp);
+ knp += 8;
+ left ^= f(key, right, knp);
+ knp += 8;
+ right ^= f(key, left, knp);
+ knp += 8;
+ left ^= f(key, right, knp);
+ knp += 8;
+ right ^= f(key, left, knp);
+ knp += 8;
+ left ^= f(key, right, knp);
+ knp += 8;
+ right ^= f(key, left, knp);
+
+ /* Left/right half swap, plus byte swap if little-endian */
+#ifndef WORDS_BIGENDIAN
+ work[1] = byteswap32(left);
+ work[0] = byteswap32(right);
+#else
+ work[0] = right;
+ work[1] = left;
+#endif
+ permute_fp((char *) work, key, block); /* Inverse initial permutation */
+}
+
+/* Permute inblock with perm */
+static void permute_ip(char *inblock, DES_KEY * key, char *outblock)
+{
+ register char *ib, *ob; /* ptr to input or output block */
+ register char *p, *q;
+ register int j;
+
+ /* Clear output block */
+ Bzero(outblock, 8);
+
+ ib = inblock;
+ for (j = 0; j < 16; j += 2, ib++) { /* for each input nibble */
+ ob = outblock;
+ p = key->iperm[j][(*ib >> 4) & 0xf];
+ q = key->iperm[j + 1][*ib & 0xf];
+ /* and each output byte, OR the masks together */
+ *ob++ |= *p++ | *q++;
+ *ob++ |= *p++ | *q++;
+ *ob++ |= *p++ | *q++;
+ *ob++ |= *p++ | *q++;
+ *ob++ |= *p++ | *q++;
+ *ob++ |= *p++ | *q++;
+ *ob++ |= *p++ | *q++;
+ *ob++ |= *p++ | *q++;
+ }
+}
+
+/* Permute inblock with perm */
+static void permute_fp(char *inblock, DES_KEY * key, char *outblock)
+{
+ register char *ib, *ob; /* ptr to input or output block */
+ register char *p, *q;
+ register int j;
+
+ /* Clear output block */
+ Bzero(outblock, 8);
+
+ ib = inblock;
+ for (j = 0; j < 16; j += 2, ib++) { /* for each input nibble */
+ ob = outblock;
+ p = key->fperm[j][(*ib >> 4) & 0xf];
+ q = key->fperm[j + 1][*ib & 0xf];
+ /* and each output byte, OR the masks together */
+ *ob++ |= *p++ | *q++;
+ *ob++ |= *p++ | *q++;
+ *ob++ |= *p++ | *q++;
+ *ob++ |= *p++ | *q++;
+ *ob++ |= *p++ | *q++;
+ *ob++ |= *p++ | *q++;
+ *ob++ |= *p++ | *q++;
+ *ob++ |= *p++ | *q++;
+ }
+}
+
+/* The nonlinear function f(r,k), the heart of DES */
+static uint32_t f(DES_KEY * key, register uint32_t r, register char *subkey)
+{
+ register uint32_t *spp;
+ register uint32_t rval, rt;
+ register int er;
+
+#ifdef TRACE
+ printf("f(%08lx, %02x %02x %02x %02x %02x %02x %02x %02x) = ",
+ r,
+ subkey[0], subkey[1], subkey[2],
+ subkey[3], subkey[4], subkey[5], subkey[6], subkey[7]);
+#endif
+ /* Run E(R) ^ K through the combined S & P boxes.
+ * This code takes advantage of a convenient regularity in
+ * E, namely that each group of 6 bits in E(R) feeding
+ * a single S-box is a contiguous segment of R.
+ */
+ subkey += 7;
+
+ /* Compute E(R) for each block of 6 bits, and run thru boxes */
+ er = ((int) r << 1) | ((r & 0x80000000) ? 1 : 0);
+ spp = &key->sp[7][0];
+ rval = spp[(er ^ *subkey--) & 0x3f];
+ spp -= 64;
+ rt = (uint32_t) r >> 3;
+ rval |= spp[((int) rt ^ *subkey--) & 0x3f];
+ spp -= 64;
+ rt >>= 4;
+ rval |= spp[((int) rt ^ *subkey--) & 0x3f];
+ spp -= 64;
+ rt >>= 4;
+ rval |= spp[((int) rt ^ *subkey--) & 0x3f];
+ spp -= 64;
+ rt >>= 4;
+ rval |= spp[((int) rt ^ *subkey--) & 0x3f];
+ spp -= 64;
+ rt >>= 4;
+ rval |= spp[((int) rt ^ *subkey--) & 0x3f];
+ spp -= 64;
+ rt >>= 4;
+ rval |= spp[((int) rt ^ *subkey--) & 0x3f];
+ spp -= 64;
+ rt >>= 4;
+ rt |= (r & 1) << 5;
+ rval |= spp[((int) rt ^ *subkey) & 0x3f];
+#ifdef TRACE
+ printf(" %08lx\n", rval);
+#endif
+ return rval;
+}
+
+/* initialize a perm array */
+static void perminit_ip(DES_KEY * key)
+{
+ register int l, j, k;
+ int i, m;
+
+ /* Clear the permutation array */
+ Bzero(key->iperm, 16 * 16 * 8);
+
+ for (i = 0; i < 16; i++) /* each input nibble position */
+ for (j = 0; j < 16; j++) /* each possible input nibble */
+ for (k = 0; k < 64; k++) { /* each output bit position */
+ l = ip[k] - 1; /* where does this bit come from */
+ if ((l >> 2) != i) /* does it come from input posn? */
+ continue; /* if not, bit k is 0 */
+ if (!(j & nibblebit[l & 3]))
+ continue; /* any such bit in input? */
+ m = k & 07; /* which bit is this in the byte */
+ key->iperm[i][j][k >> 3] |= bytebit[m];
+ }
+}
+
+static void perminit_fp(DES_KEY * key)
+{
+ register int l, j, k;
+ int i, m;
+
+ /* Clear the permutation array */
+ Bzero(key->fperm, 16 * 16 * 8);
+
+ for (i = 0; i < 16; i++) /* each input nibble position */
+ for (j = 0; j < 16; j++) /* each possible input nibble */
+ for (k = 0; k < 64; k++) { /* each output bit position */
+ l = fp[k] - 1; /* where does this bit come from */
+ if ((l >> 2) != i) /* does it come from input posn? */
+ continue; /* if not, bit k is 0 */
+ if (!(j & nibblebit[l & 3]))
+ continue; /* any such bit in input? */
+ m = k & 07; /* which bit is this in the byte */
+ key->fperm[i][j][k >> 3] |= bytebit[m];
+ }
+}
+
+/* Initialize the lookup table for the combined S and P boxes */
+static void spinit(DES_KEY * key)
+{
+ char pbox[32];
+ int p, i, s, j, rowcol;
+ uint32_t val;
+
+ /* Compute pbox, the inverse of p32i.
+ * This is easier to work with
+ */
+ for (p = 0; p < 32; p++) {
+ for (i = 0; i < 32; i++) {
+ if (p32i[i] - 1 == p) {
+ pbox[p] = i;
+ break;
+ }
+ }
+ }
+ for (s = 0; s < 8; s++) { /* For each S-box */
+ for (i = 0; i < 64; i++) { /* For each possible input */
+ val = 0;
+ /* The row number is formed from the first and last
+ * bits; the column number is from the middle 4
+ */
+ rowcol =
+ (i & 32) | ((i & 1) ? 16 : 0) | ((i >> 1) &
+ 0xf);
+ for (j = 0; j < 4; j++) { /* For each output bit */
+ if (si[s][rowcol] & (8 >> j)) {
+ val |=
+ 1L << (31 - pbox[4 * s + j]);
+ }
+ }
+ key->sp[s][i] = val;
+
+#ifdef DEBUG
+ printf("sp[%d][%2d] = %08lx\n", s, i,
+ key->sp[s][i]);
+#endif
+ }
+ }
+}
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