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/*
* mknewpc2.c
*
* Generate PC-2 tables for DES-150 library
*
* This Source Code Form is subject to the terms of the Mozilla Public
* License, v. 2.0. If a copy of the MPL was not distributed with this
typedef unsigned char BYTE;
typedef unsigned int HALF;
#define DES_ENCRYPT 0
#define DES_DECRYPT 1
/* two 28-bit registers defined in key schedule production process */
static HALF C0, D0;
static HALF L0, R0;
/* key schedule, 16 internal keys, each with 8 6-bit parts */
static BYTE KS[8][16];
/*
* This table takes the 56 bits in C0 and D0 and shows show they are
* permuted into the 8 6-bit parts of the key in the key schedule.
* The bits of C0 are numbered left to right, 1-28.
* The bits of D0 are numbered left to right, 29-56.
* Zeros in this table represent bits that are always zero.
* Note that all the bits in the first 4 rows come from C0,
* and all the bits in the second 4 rows come from D0.
*/
static const BYTE PC2[64] = {
14, 17, 11, 24, 1, 5, 0, 0, /* S1 */
3, 28, 15, 6, 21, 10, 0, 0, /* S2 */
23, 19, 12, 4, 26, 8, 0, 0, /* S3 */
16, 7, 27, 20, 13, 2, 0, 0, /* S4 */
41, 52, 31, 37, 47, 55, 0, 0, /* S5 */
30, 40, 51, 45, 33, 48, 0, 0, /* S6 */
44, 49, 39, 56, 34, 53, 0, 0, /* S7 */
46, 42, 50, 36, 29, 32, 0, 0 /* S8 */
};
/* This table represents the same info as PC2, except that
* The bits of C0 and D0 are each numbered right to left, 0-27.
* -1 values indicate bits that are always zero.
* As before all the bits in the first 4 rows come from C0,
* and all the bits in the second 4 rows come from D0.
*/
static signed char PC2a[64] = {
/* bits of C0 */
14, 11, 17, 4, 27, 23, -1, -1, /* S1 */
25, 0, 13, 22, 7, 18, -1, -1, /* S2 */
5, 9, 16, 24, 2, 20, -1, -1, /* S3 */
12, 21, 1, 8, 15, 26, -1, -1, /* S4 */
/* bits of D0 */
15, 4, 25, 19, 9, 1, -1, -1, /* S5 */
26, 16, 5, 11, 23, 8, -1, -1, /* S6 */
12, 7, 17, 0, 22, 3, -1, -1, /* S7 */
10, 14, 6, 20, 27, 24, -1, -1 /* S8 */
};
/* This table represents the same info as PC2a, except that
* The order of of the rows has been changed to increase the efficiency
* with which the key sechedule is created.
* Fewer shifts and ANDs are required to make the KS from these.
*/
static const signed char PC2b[64] = {
/* bits of C0 */
14, 11, 17, 4, 27, 23, -1, -1, /* S1 */
5, 9, 16, 24, 2, 20, -1, -1, /* S3 */
25, 0, 13, 22, 7, 18, -1, -1, /* S2 */
12, 21, 1, 8, 15, 26, -1, -1, /* S4 */
/* bits of D0 */
26, 16, 5, 11, 23, 8, -1, -1, /* S6 */
10, 14, 6, 20, 27, 24, -1, -1, /* S8 */
15, 4, 25, 19, 9, 1, -1, -1, /* S5 */
12, 7, 17, 0, 22, 3, -1, -1 /* S7 */
};
/* Only 24 of the 28 bits in C0 and D0 are used in PC2.
* The used bits of C0 and D0 are grouped into 4 groups of 6,
* so that the PC2 permutation can be accomplished with 4 lookups
* in tables of 64 entries.
* The following table shows how the bits of C0 and D0 are grouped
* into indexes for the respective table lookups.
* Bits are numbered right-to-left, 0-27, as in PC2b.
*/
static BYTE NDX[48] = {
/* Bits of C0 */
27, 26, 25, 24, 23, 22, /* C0 table 0 */
18, 17, 16, 15, 14, 13, /* C0 table 1 */
9, 8, 7, 2, 1, 0, /* C0 table 2 */
5, 4, 21, 20, 12, 11, /* C0 table 3 */
/* bits of D0 */
27, 26, 25, 24, 23, 22, /* D0 table 0 */
20, 19, 17, 16, 15, 14, /* D0 table 1 */
12, 11, 10, 9, 8, 7, /* D0 table 2 */
6, 5, 4, 3, 1, 0 /* D0 table 3 */
};
/* Here's the code that does that grouping.
left = PC2LOOKUP(0, 0, ((c0 >> 22) & 0x3F) );
left |= PC2LOOKUP(0, 1, ((c0 >> 13) & 0x3F) );
left |= PC2LOOKUP(0, 2, ((c0 >> 4) & 0x38) | (c0 & 0x7) );
left |= PC2LOOKUP(0, 3, ((c0>>18)&0xC) | ((c0>>11)&0x3) | (c0&0x30));
right = PC2LOOKUP(1, 0, ((d0 >> 22) & 0x3F) );
right |= PC2LOOKUP(1, 1, ((d0 >> 15) & 0x30) | ((d0 >> 14) & 0xf) );
right |= PC2LOOKUP(1, 2, ((d0 >> 7) & 0x3F) );
right |= PC2LOOKUP(1, 3, ((d0 >> 1) & 0x3C) | (d0 & 0x3));
*/
void
make_pc2a(void)
{
int i, j;
for (i = 0; i < 64; ++i) {
j = PC2[i];
if (j == 0)
j = -1;
else if (j < 29)
j = 28 - j;
else
j = 56 - j;
PC2a[i] = j;
}
for (i = 0; i < 64; i += 8) {
printf("%3d,%3d,%3d,%3d,%3d,%3d,%3d,%3d,\n",
PC2a[i + 0], PC2a[i + 1], PC2a[i + 2], PC2a[i + 3],
PC2a[i + 4], PC2a[i + 5], PC2a[i + 6], PC2a[i + 7]);
}
}
HALF PC2cd0[64];
HALF PC_2H[8][64];
void
mktable()
{
int i;
int table;
const BYTE* ndx = NDX;
HALF mask;
mask = 0x80000000;
for (i = 0; i < 32; ++i, mask >>= 1) {
int bit = PC2b[i];
if (bit < 0)
continue;
PC2cd0[bit + 32] = mask;
}
mask = 0x80000000;
for (i = 32; i < 64; ++i, mask >>= 1) {
int bit = PC2b[i];
if (bit < 0)
continue;
PC2cd0[bit] = mask;
}
#if DEBUG
for (i = 0; i < 64; ++i) {
printf("0x%08x,\n", PC2cd0[i]);
}
#endif
for (i = 0; i < 24; ++i) {
NDX[i] += 32; /* because c0 is the upper half */
}
for (table = 0; table < 8; ++table) {
HALF bitvals[6];
for (i = 0; i < 6; ++i) {
bitvals[5 - i] = PC2cd0[*ndx++];
}
for (i = 0; i < 64; ++i) {
int j;
int k = 0;
HALF value = 0;
for (j = i; j; j >>= 1, ++k) {
if (j & 1) {
value |= bitvals[k];
}
}
PC_2H[table][i] = value;
}
printf("/* table %d */ {\n", table);
for (i = 0; i < 64; i += 4) {
printf(" 0x%08x, 0x%08x, 0x%08x, 0x%08x, \n",
PC_2H[table][i], PC_2H[table][i + 1],
PC_2H[table][i + 2], PC_2H[table][i + 3]);
}
printf(" },\n");
}
}
int
main(void)
{
/* make_pc2a(); */
mktable();
return 0;
}