Function deskey

extern/libtomcrypt/src/ciphers/des.c:1304–1351

static void _deskey(const unsigned char *key, short edf, ulong32 *keyout)
#else
static void deskey(const unsigned char *key, short edf, ulong32 *keyout)
#endif
{
    ulong32 i, j, l, m, n, kn[32];
    unsigned char pc1m[56], pcr[56];

    for (j=0; j < 56; j++) {
        l = (ulong32)pc1[j];
        m = l & 7;
        pc1m[j] = (unsigned char)((key[l >> 3U] & bytebit[m]) == bytebit[m] ? 1 : 0);
    }

    for (i=0; i < 16; i++) {
        if (edf == DE1) {
           m = (15 - i) << 1;
        } else {
           m = i << 1;
        }
        n = m + 1;
        kn[m] = kn[n] = 0L;
        for (j=0; j < 28; j++) {
            l = j + (ulong32)totrot[i];
            if (l < 28) {
               pcr[j] = pc1m[l];
            } else {
               pcr[j] = pc1m[l - 28];
            }
        }
        for (/*j = 28*/; j < 56; j++) {
            l = j + (ulong32)totrot[i];
            if (l < 56) {
               pcr[j] = pc1m[l];
            } else {
               pcr[j] = pc1m[l - 28];
            }
        }
        for (j=0; j < 24; j++)  {
            if ((int)pcr[(int)pc2[j]] != 0) {
               kn[m] |= bigbyte[j];
            }
            if ((int)pcr[(int)pc2[j+24]] != 0) {
               kn[n] |= bigbyte[j];
            }
        }
    }

    cookey(kn, keyout);
}

#ifdef LTC_CLEAN_STACK
static void deskey(const unsigned char *key, short edf, ulong32 *keyout)