src/mcrypt/tripledes.c

/* [<][>][^][v][top][bottom][index][help] */
This source file includes following definitions.
_mcrypt_desinit
_mcrypt_set_key
_mcrypt_encrypt
_mcrypt_decrypt
permute
f
perminit
spinit
gf_crypt_register_3des

/* 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
 * Modified modified such that will operate in EDE 3DES - 1999 Nikos Mavroyanopoulos
 *
 * Callers now allocate a key schedule as follows:
 *      kn = (char (*)[8])gf_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: tripledes.c,v 1.3 2010-02-23 16:24:20 jeanlf Exp $ */

#include <gpac/internal/crypt_dev.h>

#if !defined(GPAC_CRYPT_ISMA_ONLY) && !defined(GPAC_DISABLE_MCRYPT)

typedef struct triple_des_key {
        char kn[3][16][8];
        u32 sp[3][8][64];

        char iperm[16][16][8];
        char fperm[16][16][8];

} TRIPLEDES_KEY;


static void permute(), perminit(), spinit();
static u32 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(TRIPLEDES_KEY * key)
{

        spinit(key, 0);
        spinit(key, 1);
        spinit(key, 2);
        perminit(&key->iperm, ip);
        perminit(&key->fperm, fp);


        return 0;
}


/* Set key (initialize key schedule array) */
static GF_Err _mcrypt_set_key(TRIPLEDES_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;
        char *user_key1 = &user_key[0];
        char *user_key2 = &user_key[8];
        char *user_key3 = &user_key[16];

        _mcrypt_desinit(dkey);

        /* Clear key schedule */
        Bzero(dkey->kn[0], 16 * 8);
        Bzero(dkey->kn[1], 16 * 8);
        Bzero(dkey->kn[2], 16 * 8);

        /* DES 1 */
        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_key1[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[0][i][j / 6] |= bytebit[l] >> 2;
                        }
                }
        }
        /* DES 2 */
        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_key2[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[1][i][j / 6] |= bytebit[l] >> 2;
                        }
                }
        }
        /* DES 3 */
        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_key3[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[2][i][j / 6] |= bytebit[l] >> 2;
                        }
                }
        }
        return GF_OK;
}




/* In-place encryption of 64-bit block */

static void _mcrypt_encrypt(TRIPLEDES_KEY * key, char *block)
{
        register u32 left, right;
        register char *knp;
        u32 work[2];            /* Working data storage */

        /* DES 1 */
        permute(block, key->iperm, (char *) work);      /* Initial Permutation */
#ifndef WORDS_BIGENDIAN
        left = byteswap32(work[0]);
        right = byteswap32(work[1]);
#else
        left = work[0];
        right = work[1];
#endif

        /* 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][0];
        left ^= f(key, 0, right, knp);
        knp += 8;
        right ^= f(key, 0, left, knp);
        knp += 8;
        left ^= f(key, 0, right, knp);
        knp += 8;
        right ^= f(key, 0, left, knp);
        knp += 8;
        left ^= f(key, 0, right, knp);
        knp += 8;
        right ^= f(key, 0, left, knp);
        knp += 8;
        left ^= f(key, 0, right, knp);
        knp += 8;
        right ^= f(key, 0, left, knp);
        knp += 8;
        left ^= f(key, 0, right, knp);
        knp += 8;
        right ^= f(key, 0, left, knp);
        knp += 8;
        left ^= f(key, 0, right, knp);
        knp += 8;
        right ^= f(key, 0, left, knp);
        knp += 8;
        left ^= f(key, 0, right, knp);
        knp += 8;
        right ^= f(key, 0, left, knp);
        knp += 8;
        left ^= f(key, 0, right, knp);
        knp += 8;
        right ^= f(key, 0, left, knp);

        /* DES 2 */

        /* Do the 16 rounds in reverse order.
         * The rounds are numbered from 15 to 0. 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[1][15][0];
        right ^= f(key, 1, left, knp);
        knp -= 8;
        left ^= f(key, 1, right, knp);
        knp -= 8;
        right ^= f(key, 1, left, knp);
        knp -= 8;
        left ^= f(key, 1, right, knp);
        knp -= 8;
        right ^= f(key, 1, left, knp);
        knp -= 8;
        left ^= f(key, 1, right, knp);
        knp -= 8;
        right ^= f(key, 1, left, knp);
        knp -= 8;
        left ^= f(key, 1, right, knp);
        knp -= 8;
        right ^= f(key, 1, left, knp);
        knp -= 8;
        left ^= f(key, 1, right, knp);
        knp -= 8;
        right ^= f(key, 1, left, knp);
        knp -= 8;
        left ^= f(key, 1, right, knp);
        knp -= 8;
        right ^= f(key, 1, left, knp);
        knp -= 8;
        left ^= f(key, 1, right, knp);
        knp -= 8;
        right ^= f(key, 1, left, knp);
        knp -= 8;
        left ^= f(key, 1, right, knp);

        /* 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[2][0][0];
        left ^= f(key, 2, right, knp);
        knp += 8;
        right ^= f(key, 2, left, knp);
        knp += 8;
        left ^= f(key, 2, right, knp);
        knp += 8;
        right ^= f(key, 2, left, knp);
        knp += 8;
        left ^= f(key, 2, right, knp);
        knp += 8;
        right ^= f(key, 2, left, knp);
        knp += 8;
        left ^= f(key, 2, right, knp);
        knp += 8;
        right ^= f(key, 2, left, knp);
        knp += 8;
        left ^= f(key, 2, right, knp);
        knp += 8;
        right ^= f(key, 2, left, knp);
        knp += 8;
        left ^= f(key, 2, right, knp);
        knp += 8;
        right ^= f(key, 2, left, knp);
        knp += 8;
        left ^= f(key, 2, right, knp);
        knp += 8;
        right ^= f(key, 2, left, knp);
        knp += 8;
        left ^= f(key, 2, right, knp);
        knp += 8;
        right ^= f(key, 2, 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((char *) work, key->fperm, block);      /* Inverse initial permutation */

}

/* In-place decryption of 64-bit block. This function is the mirror
 * image of encryption; exactly the same steps are taken, but in
 * reverse order
 */
static void _mcrypt_decrypt(TRIPLEDES_KEY * key, char *block)
{
        register u32 left, right;
        register char *knp;
        u32 work[2];            /* Working data storage */

        permute(block, key->iperm, (char *) work);      /* Initial permutation */

        /* Left/right half swap, plus byte swap if little-endian */
#ifndef WORDS_BIGENDIAN
        right = byteswap32(work[0]);
        left = byteswap32(work[1]);
#else
        right = work[0];
        left = work[1];
#endif

        /* DES 3 */

        /* Do the 16 rounds in reverse order.
         * The rounds are numbered from 15 to 0. 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[2][15][0];
        right ^= f(key, 2, left, knp);
        knp -= 8;
        left ^= f(key, 2, right, knp);
        knp -= 8;
        right ^= f(key, 2, left, knp);
        knp -= 8;
        left ^= f(key, 2, right, knp);
        knp -= 8;
        right ^= f(key, 2, left, knp);
        knp -= 8;
        left ^= f(key, 2, right, knp);
        knp -= 8;
        right ^= f(key, 2, left, knp);
        knp -= 8;
        left ^= f(key, 2, right, knp);
        knp -= 8;
        right ^= f(key, 2, left, knp);
        knp -= 8;
        left ^= f(key, 2, right, knp);
        knp -= 8;
        right ^= f(key, 2, left, knp);
        knp -= 8;
        left ^= f(key, 2, right, knp);
        knp -= 8;
        right ^= f(key, 2, left, knp);
        knp -= 8;
        left ^= f(key, 2, right, knp);
        knp -= 8;
        right ^= f(key, 2, left, knp);
        knp -= 8;
        left ^= f(key, 2, right, knp);


        /* DES 2*/
        /* 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[1][0][0];
        left ^= f(key, 1, right, knp);
        knp += 8;
        right ^= f(key, 1, left, knp);
        knp += 8;
        left ^= f(key, 1, right, knp);
        knp += 8;
        right ^= f(key, 1, left, knp);
        knp += 8;
        left ^= f(key, 1, right, knp);
        knp += 8;
        right ^= f(key, 1, left, knp);
        knp += 8;
        left ^= f(key, 1, right, knp);
        knp += 8;
        right ^= f(key, 1, left, knp);
        knp += 8;
        left ^= f(key, 1, right, knp);
        knp += 8;
        right ^= f(key, 1, left, knp);
        knp += 8;
        left ^= f(key, 1, right, knp);
        knp += 8;
        right ^= f(key, 1, left, knp);
        knp += 8;
        left ^= f(key, 1, right, knp);
        knp += 8;
        right ^= f(key, 1, left, knp);
        knp += 8;
        left ^= f(key, 1, right, knp);
        knp += 8;
        right ^= f(key, 1, left, knp);

        /* DES 1 */
        /* Do the 16 rounds in reverse order.
         * The rounds are numbered from 15 to 0. 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][15][0];
        right ^= f(key, 0, left, knp);
        knp -= 8;
        left ^= f(key, 0, right, knp);
        knp -= 8;
        right ^= f(key, 0, left, knp);
        knp -= 8;
        left ^= f(key, 0, right, knp);
        knp -= 8;
        right ^= f(key, 0, left, knp);
        knp -= 8;
        left ^= f(key, 0, right, knp);
        knp -= 8;
        right ^= f(key, 0, left, knp);
        knp -= 8;
        left ^= f(key, 0, right, knp);
        knp -= 8;
        right ^= f(key, 0, left, knp);
        knp -= 8;
        left ^= f(key, 0, right, knp);
        knp -= 8;
        right ^= f(key, 0, left, knp);
        knp -= 8;
        left ^= f(key, 0, right, knp);
        knp -= 8;
        right ^= f(key, 0, left, knp);
        knp -= 8;
        left ^= f(key, 0, right, knp);
        knp -= 8;
        right ^= f(key, 0, left, knp);
        knp -= 8;
        left ^= f(key, 0, right, knp);


#ifndef WORDS_BIGENDIAN
        work[0] = byteswap32(left);
        work[1] = byteswap32(right);
#else
        work[0] = left;
        work[1] = right;
#endif
        permute((char *) work, key->fperm, block);      /* Inverse initial permutation */
}

/* Permute inblock with perm */
static void permute(char *inblock, char perm[16][16][8], char *outblock)
{
        register char *ib, *ob; /* ptr to input or output block */
        register char *p, *q;
        register int j;

        if (perm == NULL) {
                /* No permutation, just copy */
                memmove(outblock, inblock, 8);
                return;
        }
        /* Clear output block */
        Bzero(outblock, 8);

        ib = inblock;
        for (j = 0; j < 16; j += 2, ib++) {     /* for each input nibble */
                ob = outblock;
                p = perm[j][(*ib >> 4) & 0xf];
                q = perm[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 u32 f(TRIPLEDES_KEY * key, int pos, register u32 r,
             register char *subkey)
{
        register u32 *spp;
        register u32 rval, rt;
        register int er;

#ifdef  TRACE
        fprintf(stderr, "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[pos][7][0];
        rval = spp[(er ^ *subkey--) & 0x3f];
        spp -= 64;
        rt = (u32) 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
        fprintf(stderr, " %08lx\n", rval);
#endif
        return rval;
}

/* initialize a perm array */
static void perminit(char perm[16][16][8], char p[64])
{
        register int l, j, k;
        int i, m;

        /* Clear the permutation array */
        Bzero((char *) perm, 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 = p[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 */
                                perm[i][j][k >> 3] |= bytebit[m];
                        }
}

/* Initialize the lookup table for the combined S and P boxes */
static void spinit(TRIPLEDES_KEY * key, int pos)
{
        char pbox[32];
        int p, i, s, j, rowcol;
        u32 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[pos][s][i] = val;
                }
        }
}

void gf_crypt_register_3des(GF_Crypt *td)
{
        td->a_encrypt = _mcrypt_encrypt;
        td->a_decrypt = _mcrypt_decrypt;
        td->a_set_key = _mcrypt_set_key;
        td->algo_name = "3DES";
        td->algo_version = 19991129;
        td->num_key_sizes = 1;
        td->key_sizes[0] = 24;
        td->key_size = 24;
        td->is_block_algo = 1;
        td->algo_block_size = 8;
        td->algo_size = sizeof(TRIPLEDES_KEY);
}

#endif /* !defined(GPAC_CRYPT_ISMA_ONLY) && !defined(GPAC_DISABLE_MCRYPT)*/
/* [<][>][^][v][top][bottom][index][help] */
root/src/mcrypt/tripledes.c

DEFINITIONS
