ack/lang/cem/libcc/gen/crypt.c
1987-01-27 15:57:55 +00:00

295 lines
6.5 KiB
C

/* From Andy Tanenbaum's book "Computer Networks",
rewritten in C
*/
struct block {
unsigned char b_data[64];
};
struct ordering {
unsigned char o_data[64];
};
static struct block key;
static struct ordering InitialTr = {
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,
};
static struct ordering FinalTr = {
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,
};
static struct ordering swap = {
33,34,35,36,37,38,39,40,41,42,43,44,45,46,47,48,
49,50,51,52,53,54,55,56,57,58,59,60,61,62,63,64,
1, 2, 3, 4, 5, 6, 7, 8, 9,10,11,12,13,14,15,16,
17,18,19,20,21,22,23,24,25,26,27,28,29,30,31,32,
};
static struct ordering KeyTr1 = {
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,
};
static struct ordering KeyTr2 = {
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,
};
static struct ordering etr = {
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,
};
static struct ordering ptr = {
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,
};
static unsigned char s_boxes[8][64] = {
{ 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,
},
{ 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,
},
{ 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,
},
{ 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,
},
{ 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,
},
{ 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,
},
{ 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,
},
{ 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,
},
};
static int rots[] = {
1,1,2,2,2,2,2,2,1,2,2,2,2,2,2,1,
};
static
transpose(data, t, n)
register struct block *data;
register struct ordering *t;
register int n;
{
struct block x;
x = *data;
while (n-- > 0) {
data->b_data[n] = x.b_data[t->o_data[n] - 1];
}
}
static
rotate(key)
register struct block *key;
{
register unsigned char *p = key->b_data;
register unsigned char *ep = &(key->b_data[55]);
int data0 = key->b_data[0], data28 = key->b_data[28];
while (p++ < ep) *(p-1) = *p;
key->b_data[27] = data0;
key->b_data[55] = data28;
}
static struct ordering *EP = &etr;
static
f(i, key, a, x)
struct block *key, *a;
register struct block *x;
{
struct block e, ikey, y;
int k;
register unsigned char *p, *q, *r;
e = *a;
transpose(&e, EP, 48);
for (k = rots[i]; k; k--) rotate(key);
ikey = *key;
transpose(&ikey, &KeyTr2, 48);
p = &(y.b_data[48]);
q = &(e.b_data[48]);
r = &(ikey.b_data[48]);
while (p > y.b_data) {
*--p = *--q ^ *--r;
}
q = x->b_data;
for (k = 0; k < 8; k++) {
register int xb, r;
r = *p++ << 5;
r += *p++ << 3;
r += *p++ << 2;
r += *p++ << 1;
r += *p++;
r += *p++ << 4;
xb = s_boxes[k][r];
*q++ = (xb >> 3) & 1;
*q++ = (xb>>2) & 1;
*q++ = (xb>>1) & 1;
*q++ = (xb & 1);
}
transpose(x, &ptr, 32);
}
setkey(k)
register char *k;
{
key = *((struct block *) k);
transpose(&key, &KeyTr1, 56);
}
encrypt(blck, edflag)
char *blck;
{
register struct block *p = (struct block *) blck;
register int i;
transpose(p, &InitialTr, 64);
for (i = 15; i>= 0; i--) {
int j = edflag ? i : 15 - i;
register int k;
struct block b, x;
b = *p;
for (k = 31; k >= 0; k--) {
p->b_data[k] = b.b_data[k + 32];
}
f(j, &key, p, &x);
for (k = 31; k >= 0; k--) {
p->b_data[k+32] = b.b_data[k] ^ x.b_data[k];
}
}
transpose(p, &swap, 64);
transpose(p, &FinalTr, 64);
}
char *
crypt(pw,salt)
register char *pw;
char *salt;
{
/* Unfortunately, I had to look at the sources of V7 crypt.
There was no other way to find out what this routine
actually does.
*/
char pwb[66];
static char result[16];
register char *p = pwb;
struct ordering new_etr;
register int i;
while (*pw && p < &pwb[64]) {
register int j = 7;
while (j--) {
*p++ = (*pw >> j) & 01;
}
pw++;
*p++ = 0;
}
while (p < &pwb[64]) *p++ = 0;
setkey(p = pwb);
while (p < &pwb[66]) *p++ = 0;
new_etr = etr;
EP = &new_etr;
for (i = 0; i < 2; i++) {
register char c = *salt++;
register int j;
result[i] = c;
if ( c > 'Z') c -= 6 + 7 + '.'; /* c was a lower case letter */
else if ( c > '9') c -= 7 + '.';/* c was upper case letter */
else c -= '.'; /* c was digit, '.' or '/'. */
/* now, 0 <= c <= 63 */
for (j = 0; j < 6; j++) {
if ((c >> j) & 01) {
int t = 6*i + j;
int temp = new_etr.o_data[t];
new_etr.o_data[t] = new_etr.o_data[t+24];
new_etr.o_data[t+24] = temp;
}
}
}
if (result[1] == 0) result[1] = result[0];
for (i = 0; i < 25; i++) encrypt(pwb,0);
EP = &etr;
p = pwb;
pw = result+2;
while (p < &pwb[66]) {
register int c = 0;
register int j = 6;
while (j--) {
c <<= 1;
c |= *p++;
}
c += '.'; /* becomes >= '.' */
if (c > '9') c += 7; /* not in [./0-9], becomes upper */
if (c > 'Z') c += 6; /* not in [A-Z], becomes lower */
*pw++ = c;
}
*pw = 0;
return result;
}