void
zmodpowu(z_t a, z_t b, unsigned long long int c, z_t d)
{
if (unlikely(!c)) {
if (check(zzero(b)))
libzahl_failure(-ZERROR_0_POW_0);
else if (check(zzero(d)))
libzahl_failure(-ZERROR_DIV_0);
else
zsetu(a, 1);
return;
} else if (check(zzero(d))) {
libzahl_failure(-ZERROR_DIV_0);
} else if (unlikely(zzero(b))) {
SET_SIGNUM(a, 0);
return;
}
zmod(tb, b, d);
zset(td, d);
if (c & 1)
zset(a, tb);
else
zsetu(a, 1);
while (c >>= 1) {
zmodsqr(tb, tb, td);
if (c & 1)
zmodmul(a, a, tb, td);
}
}
int PollardRho(verylong zalpha, verylong zbeta,
verylong zn, verylong zp, verylong *zx)
{
long i = 2, j;
static verylong za0 = 0, za1 = 0, za2 = 0, za3 = 0;
static verylong zb0 = 0, zb1 = 0, zb2 = 0, zb3 = 0;
static verylong zx0 = 0, zx1 = 0, zx2 = 0, zx3 = 0;
static verylong zr = 0, zri = 0;
zone(&zx0);
zzero(&za0);
zzero(&zb0);
zfi(zalpha, zbeta, zp, zx0, &zx1);
zai(za0, zn, zx0, &za1);
zbi(zb0, zn, zx0, &zb1);
zfi(zalpha, zbeta, zp, zx1, &zx2);
zai(za1, zn, zx1, &za2);
zbi(zb1, zn, zx1, &zb2);
zcopy(za1, &za0);
zcopy(zb1, &zb0);
zcopy(zx1, &zx0);
for (;;) {
zfi(zalpha, zbeta, zp, zx0, &zx1);
zai(za0, zn, zx0, &za1);
zbi(zb0, zn, zx0, &zb1);
zcopy(za1, &za2);
zcopy(zb1, &zb2);
zcopy(zx1, &zx2);
i++;
for (j = 0; j < i; j++) {
zfi(zalpha, zbeta, zp, zx2, &zx3);
zai(za2, zn, zx2, &za3);
zbi(zb2, zn, zx2, &zb3);
zcopy(za3, &za2);
zcopy(zb3, &zb2);
zcopy(zx3, &zx2);
}
if (zcompare(zx1, zx3) == 0) {
zsubmod(zb1, zb3, zn, &zr);
if (zscompare(zr, 0) == 0) return 0;
zinvmod(zr, zn, &zri);
zsub(za3, za1, &za0);
zmulmod(za0, zri, zn, zx);
return 1;
}
zcopy(za1, &za0);
zcopy(zb1, &zb0);
zcopy(zx1, &zx0);
}
}
void scalar(long n, verylong *za, verylong *zb,
verylong *zs)
{
/* *s = inner_product(a, b) */
long i;
verylong zt = 0, zu = 0;
zzero(zs);
for (i = 1; i <= n; i++) {
zmul(za[i], zb[i], &zt);
zadd(zt, *zs, &zu);
zcopy(zu, zs);
}
zfree(&zt);
zfree(&zu);
}
void Montgomery_multiplication(long b, long n,
verylong zm, verylong zx,
verylong zy, verylong *zA)
{
long i, n1 = n + 1, u, mp, *a, *m, *x, *y;
verylong za = 0, zb = 0, zc = 0, zd = 0, zs = 0;
a = calloc(n1, sizeof(long));
m = calloc(n1, sizeof(long));
x = calloc(n1, sizeof(long));
y = calloc(n1, sizeof(long));
if (a == 0 || m == 0 || x == 0 || y == 0) {
printf("*error*\ncan't get memory from Montgomery");
printf(" multiplication");
exit(1);
}
zintoz(b, &zb);
zinvmod(zm, zb, &za);
znegate(&za);
mp = zsmod(za, b);
radix_representation(b, n1, m, zm);
radix_representation(b, n1, x, zx);
radix_representation(b, n1, y, zy);
zzero(zA);
for (i = 0; i < n; i++) {
radix_representation(b, n1, a, *zA);
u = ((a[0] + x[i] * y[0]) * mp) % b;
zsmul(zy, x[i], &za);
zsmul(zm, u, &zc);
zadd(*zA, za, &zs);
zadd(zs, zc, &zd);
zsdiv(zd, b, zA);
}
if (zcompare(*zA, zm) >= 0) {
zsub(*zA, zm, &za);
zcopy(za, zA);
}
free(a);
free(m);
free(x);
free(y);
zfree(&za);
zfree(&zb);
zfree(&zc);
zfree(&zd);
zfree(&zs);
}
void zbinary_ext_gcd(verylong zx, verylong zy,
verylong *za, verylong *zb,
verylong *zv)
/* returns a * x + b * y = v, v = gcd(x, y) */
{
verylong zA = 0, zB = 0, zC = 0, zD = 0;
verylong zX = 0, zY = 0, zc = 0, zg = 0;
verylong zu = 0;
zone(&zg);
zcopy(zx, &zX);
zcopy(zy, &zY);
while (!zodd(zX) && !zodd(zY)) {
zrshift(zX, 1l, &zc);
zcopy(zc, &zX);
zrshift(zY, 1l, &zc);
zcopy(zc, &zY);
zlshift(zg, 1l, &zc);
zcopy(zc, &zg);
}
zcopy(zX, &zu);
zcopy(zY, zv);
zone(&zA);
zzero(&zB);
zzero(&zC);
zone(&zD);
do {
while (!zodd(zu)) {
zrshift(zu, 1l, &zc);
zcopy(zc, &zu);
if (!zodd(zA) && !zodd(zB)) {
zrshift(zA, 1l, &zc);
zcopy(zc, &zA);
zrshift(zB, 1l, &zc);
zcopy(zc, &zB);
}
else {
zadd(zA, zY, &zc);
zrshift(zc, 1l, &zA);
zsub(zB, zX, &zc);
zrshift(zc, 1l, &zB);
}
}
while (!zodd(*zv)) {
zrshift(*zv, 1l, &zc);
zcopy(zc, zv);
if (!zodd(zC) && !zodd(zD)) {
zrshift(zC, 1l, &zc);
zcopy(zc, &zC);
zrshift(zD, 1l, &zc);
zcopy(zc, &zD);
}
else {
zadd(zC, zY, &zc);
zrshift(zc, 1l, &zC);
zsub(zD, zX, &zc);
zrshift(zc, 1l, &zD);
}
}
if (zcompare(zu, *zv) >= 0) {
zsub(zu, *zv, &zc);
zcopy(zc, &zu);
zsub(zA, zC, &zc);
zcopy(zc, &zA);
zsub(zB, zD, &zc);
zcopy(zc, &zB);
}
else {
zsub(*zv, zu, &zc);
zcopy(zc, zv);
zsub(zC, zA, &zc);
zcopy(zc, &zC);
zsub(zD, zB, &zc);
zcopy(zc, &zD);
}
#ifdef DEBUG
zwrite(zu); printf(" ");
zwrite(*zv); printf(" ");
zwrite(zA); printf(" ");
zwrite(zB); printf(" ");
zwrite(zC); printf(" ");
zwriteln(zD);
#endif
} while (zscompare(zu, 0l) != 0);
zcopy(zC, za);
zcopy(zD, zb);
zmul(zg, *zv, &zc);
zcopy(zc, zv);
zfree(&zA);
zfree(&zB);
zfree(&zC);
zfree(&zD);
zfree(&zX);
zfree(&zY);
zfree(&zc);
zfree(&zg);
zfree(&zu);
}
void int_LLL(long n, verylong **zb, verylong **zh)
{
double x, y;
long i, j, k = 2, k1, kmax = 1, l;
verylong zr = 0, zs = 0, zt = 0, zu = 0;
verylong *zB = allocate_very_vector(1, n);
verylong *zd = allocate_very_vector(0, n);
verylong **zl = allocate_very_matrix(1, n, 1, n);
zone(&zd[0]);
scalar(n, zb[1], zb[1], &zd[1]);
for (i = 1; i <= n; i++) {
for (j = 1; j <= n; j++)
zzero(&zh[i][j]);
zone(&zh[i][i]);
}
#ifdef DEBUG
if (n <= 17) {
printf("the basis to be reduced is:\n");
for (i = 1; i <= n; i++) {
for (j = 1; j <= n; j++) {
zwrite(zb[i][j]);
printf(" ");
}
printf("\n");
}
}
#endif
L2:
if (k <= kmax) goto L3;
kmax = k;
for (j = 1; j <= k; j++) {
scalar(n, zb[k], zb[j], &zu);
for (i = 1; i <= j - 1; i++) {
zmul(zd[i], zu, &zr);
zmul(zl[k][i], zl[j][i], &zs);
zsub(zr, zs, &zt);
zdiv(zt, zd[i - 1], &zu, &zr);
}
if (j < k) zcopy(zu, &zl[k][j]);
else if (j == k) {
zcopy(zu, &zd[k]);
if (zscompare(zd[k], 0l) == 0)
system_error("Failure in int_LLL.");
}
}
L3:
k1 = k - 1;
RED(k, k1, n, zd, zb, zh, zl);
zmul(zd[k], zd[k - 2], &zr);
zsq(zd[k1], &zs);
zsq(zl[k][k1], &zt);
x = zdoub(zr);
y = 3.0 * zdoub(zs) / 4.0 - zdoub(zt);
if (x < y) {
SWAP(k, k1, kmax, n, zd, zb, zh, zl);
k = max(2, k1);
goto L3;
}
for (l = k - 2; l >= 1; l--)
RED(k, l, n, zd, zb, zh, zl);
if (++k <= n) goto L2;
#ifdef DEBUG
if (n <= 17) {
printf("the LLL-reduced basis is:\n");
for (i = 1; i <= n; i++) {
for (j = 1; j <= n; j++) {
zwrite(zb[i][j]);
printf(" ");
}
printf("\n");
}
}
#endif
free_very_matrix(zl, 1, n, 1, n);
free_very_vector(zB, 1, n);
free_very_vector(zd, 0, n);
zfree(&zr);
zfree(&zs);
zfree(&zt);
zfree(&zu);
}
