diff options
author | wukong <rebirthmonkey@gmail.com> | 2015-11-23 17:48:48 +0100 |
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committer | wukong <rebirthmonkey@gmail.com> | 2015-11-23 17:48:48 +0100 |
commit | fca74d4bc3569506a6659880a89aa009dc11f552 (patch) | |
tree | 4cefd06af989608ea8ebd3bc6306889e2a1ad175 /moon-abe/pbc-0.5.14/arith/fieldquadratic.c | |
parent | 840ac3ebca7af381132bf7e93c1e4c0430d6b16a (diff) |
moon-abe cleanup
Change-Id: Ie1259856db03f0b9e80de3e967ec6bd1f03191b3
Diffstat (limited to 'moon-abe/pbc-0.5.14/arith/fieldquadratic.c')
-rw-r--r-- | moon-abe/pbc-0.5.14/arith/fieldquadratic.c | 692 |
1 files changed, 0 insertions, 692 deletions
diff --git a/moon-abe/pbc-0.5.14/arith/fieldquadratic.c b/moon-abe/pbc-0.5.14/arith/fieldquadratic.c deleted file mode 100644 index bfb46027..00000000 --- a/moon-abe/pbc-0.5.14/arith/fieldquadratic.c +++ /dev/null @@ -1,692 +0,0 @@ -// Quadratic extension fields. -// -// The fq_ functions are for general quadratic extensions. -// The fi_ functions are faster versions of some of these functions specialized -// for fields extended by sqrt(-1). -// TODO: Instead of lazily generating a quadratic nonresidue, in this case -// we can use sqrt(base field nqr) as the nqr of the extension. - -#include <ctype.h> -#include <stdarg.h> -#include <stdio.h> -#include <stdint.h> // for intptr_t -#include <stdlib.h> -#include <gmp.h> -#include "pbc_utils.h" -#include "pbc_field.h" -#include "pbc_multiz.h" -#include "pbc_fieldquadratic.h" -#include "pbc_memory.h" - -// Per-element data. -typedef struct { - // Elements have the form x + ya, where a is the square root of a quadratic - // nonresidue in the base field. - element_t x; - element_t y; -} *eptr; - -// Per-field data: we use ''data'' as a field_ptr to the base field. - -// Return the quadratic nonresidue used to build this field. -// Should only be called from routines used exclusively by the generic quadratic -// extension code. -static inline element_ptr fq_nqr(field_ptr f) { - return field_get_nqr((field_ptr) f->data); -} - -static void fq_init(element_ptr e) { - eptr p = e->data = pbc_malloc(sizeof(*p)); - field_ptr f = e->field->data; - element_init(p->x, f); - element_init(p->y, f); -} - -static void fq_clear(element_ptr e) { - eptr p = e->data; - element_clear(p->x); - element_clear(p->y); - pbc_free(e->data); -} - -static void fq_set_si(element_ptr e, signed long int i) { - eptr p = e->data; - element_set_si(p->x, i); - element_set0(p->y); -} - -static void fq_set_mpz(element_ptr e, mpz_t z) { - eptr p = e->data; - element_set_mpz(p->x, z); - element_set0(p->y); -} - -// Projection: attempts to convert Re(e) to mpz. -static void fq_to_mpz(mpz_t z, element_ptr e) { - eptr p = e->data; - element_to_mpz(z, p->x); -} - -static void fq_set0(element_ptr e) { - eptr p = e->data; - element_set0(p->x); - element_set0(p->y); -} - -static void fq_set1(element_ptr e) { - eptr p = e->data; - element_set1(p->x); - element_set0(p->y); -} - -static int fq_is0(element_ptr e) { - eptr p = e->data; - return element_is0(p->x) && element_is0(p->y); -} - -static int fq_is1(element_ptr e) { - eptr p = e->data; - return element_is1(p->x) && element_is0(p->y); -} - -static size_t fq_out_str(FILE *stream, int base, element_ptr e) { - size_t result = 4, status; - eptr p = e->data; - if (EOF == fputc('[', stream)) return 0; - result = element_out_str(stream, base, p->x); - if (!result) return 0; - if (EOF == fputs(", ", stream)) return 0; - status = element_out_str(stream, base, p->y); - if (!status) return 0; - if (EOF == fputc(']', stream)) return 0; - return result + status; -} - -static int fq_snprint(char *s, size_t n, element_ptr e) { - eptr p = e->data; - size_t result = 0, left; - int status; - - #define clip_sub() { \ - result += status; \ - left = result >= n ? 0 : n - result; \ - } - - status = snprintf(s, n, "["); - if (status < 0) return status; - clip_sub(); - status = element_snprint(s + result, left, p->x); - if (status < 0) return status; - clip_sub(); - status = snprintf(s + result, left, ", "); - if (status < 0) return status; - clip_sub(); - status = element_snprint(s + result, left, p->y); - if (status < 0) return status; - clip_sub(); - status = snprintf(s + result, left, "]"); - if (status < 0) return status; - return result + status; - #undef clip_sub -} - -static void fq_set_multiz(element_ptr e, multiz m) { - eptr p = e->data; - if (multiz_is_z(m)) { - element_set_multiz(p->x, m); - element_set0(p->y); - return; - } - element_set_multiz(p->x, multiz_at(m, 0)); - if (2 > multiz_count(m)) element_set0(p->y); - else element_set_multiz(p->y, multiz_at(m, 1)); -} - -static int fq_set_str(element_ptr e, const char *s, int base) { - const char *cp = s; - element_set0(e); - while (*cp && isspace(*cp)) cp++; - if (*cp++ != '[') return 0; - eptr p = e->data; - cp += element_set_str(p->x, cp, base); - while (*cp && isspace(*cp)) cp++; - if (*cp++ != ',') return 0; - cp += element_set_str(p->y, cp, base); - if (*cp++ != ']') return 0; - return cp - s; -} - -static int fq_sign(element_ptr n) { - int res; - eptr r = n->data; - res = element_sign(r->x); - if (!res) return element_sign(r->y); - return res; -} - -static void fq_add(element_ptr n, element_ptr a, element_ptr b) { - eptr p = a->data; - eptr q = b->data; - eptr r = n->data; - element_add(r->x, p->x, q->x); - element_add(r->y, p->y, q->y); -} - -static void fq_double(element_ptr n, element_ptr a) { - eptr p = a->data; - eptr r = n->data; - element_double(r->x, p->x); - element_double(r->y, p->y); -} - -static void fq_sub(element_ptr n, element_ptr a, element_ptr b) { - eptr p = a->data; - eptr q = b->data; - eptr r = n->data; - element_sub(r->x, p->x, q->x); - element_sub(r->y, p->y, q->y); -} - -static void fq_set(element_ptr n, element_ptr a) { - eptr p = a->data; - eptr r = n->data; - element_set(r->x, p->x); - element_set(r->y, p->y); -} - -static void fq_mul(element_ptr n, element_ptr a, element_ptr b) { - eptr p = a->data; - eptr q = b->data; - eptr r = n->data; - - element_ptr nqr = fq_nqr(n->field); - element_t e0, e1, e2; - - element_init(e0, p->x->field); - element_init(e1, e0->field); - element_init(e2, e0->field); - /* naive: - element_mul(e0, p->x, q->x); - element_mul(e1, p->y, q->y); - element_mul(e1, e1, nqr); - element_add(e0, e0, e1); - element_mul(e1, p->x, q->y); - element_mul(e2, p->y, q->x); - element_add(e1, e1, e2); - element_set(r->x, e0); - element_set(r->y, e1); - */ - // Karatsuba: - element_add(e0, p->x, p->y); - element_add(e1, q->x, q->y); - element_mul(e2, e0, e1); - element_mul(e0, p->x, q->x); - element_mul(e1, p->y, q->y); - element_mul(r->x, e1, nqr); - element_add(r->x, r->x, e0); - element_sub(e2, e2, e0); - element_sub(r->y, e2, e1); - - element_clear(e0); - element_clear(e1); - element_clear(e2); -} - -static void fq_mul_mpz(element_ptr n, element_ptr a, mpz_ptr z) { - eptr p = a->data; - eptr r = n->data; - element_mul_mpz(r->x, p->x, z); - element_mul_mpz(r->y, p->y, z); -} - -static void fq_mul_si(element_ptr n, element_ptr a, signed long int z) { - eptr p = a->data; - eptr r = n->data; - element_mul_si(r->x, p->x, z); - element_mul_si(r->y, p->y, z); -} - -static void fq_square(element_ptr n, element_ptr a) { - eptr p = a->data; - eptr r = n->data; - element_ptr nqr = fq_nqr(n->field); - element_t e0, e1; - - element_init(e0, p->x->field); - element_init(e1, e0->field); - element_square(e0, p->x); - element_square(e1, p->y); - element_mul(e1, e1, nqr); - element_add(e0, e0, e1); - element_mul(e1, p->x, p->y); - //TODO: which is faster? - //element_add(e1, e1, e1); - element_double(e1, e1); - element_set(r->x, e0); - element_set(r->y, e1); - element_clear(e0); - element_clear(e1); -} - -static void fq_neg(element_ptr n, element_ptr a) { - eptr p = a->data; - eptr r = n->data; - element_neg(r->x, p->x); - element_neg(r->y, p->y); -} - -static void fq_random(element_ptr e) { - eptr p = e->data; - element_random(p->x); - element_random(p->y); -} - -static int fq_cmp(element_ptr a, element_ptr b) { - eptr p = a->data; - eptr q = b->data; - return element_cmp(p->x, q->x) || element_cmp(p->y, q->y); -} - -static void fq_invert(element_ptr n, element_ptr a) { - eptr p = a->data; - eptr r = n->data; - element_ptr nqr = fq_nqr(n->field); - element_t e0, e1; - - element_init(e0, p->x->field); - element_init(e1, e0->field); - element_square(e0, p->x); - element_square(e1, p->y); - element_mul(e1, e1, nqr); - element_sub(e0, e0, e1); - element_invert(e0, e0); - element_mul(r->x, p->x, e0); - element_neg(e0, e0); - element_mul(r->y, p->y, e0); - - element_clear(e0); - element_clear(e1); -} - -static void fq_from_hash(element_ptr n, void *data, int len) { - eptr r = n->data; - int k = len / 2; - element_from_hash(r->x, data, k); - element_from_hash(r->y, (char *)data + k, len - k); -} - -static int fq_length_in_bytes(element_ptr e) { - eptr p = e->data; - return element_length_in_bytes(p->x) + element_length_in_bytes(p->y); -} - -static int fq_to_bytes(unsigned char *data, element_t e) { - eptr p = e->data; - int len; - len = element_to_bytes(data, p->x); - len += element_to_bytes(data + len, p->y); - return len; -} - -static int fq_from_bytes(element_t e, unsigned char *data) { - eptr p = e->data; - int len; - len = element_from_bytes(p->x, data); - len += element_from_bytes(p->y, data + len); - return len; -} - -static int fq_is_sqr(element_ptr e) { - //x + y sqrt(nqr) is a square iff x^2 - nqr y^2 is (in the base field) - eptr p = e->data; - element_t e0, e1; - element_ptr nqr = fq_nqr(e->field); - int result; - element_init(e0, p->x->field); - element_init(e1, e0->field); - element_square(e0, p->x); - element_square(e1, p->y); - element_mul(e1, e1, nqr); - element_sub(e0, e0, e1); - result = element_is_sqr(e0); - element_clear(e0); - element_clear(e1); - return result; -} - -static void fq_sqrt(element_ptr n, element_ptr e) { - eptr p = e->data; - eptr r = n->data; - element_ptr nqr = fq_nqr(n->field); - element_t e0, e1, e2; - - //if (a+b sqrt(nqr))^2 = x+y sqrt(nqr) then - //2a^2 = x +- sqrt(x^2 - nqr y^2) - //(take the sign which allows a to exist) - //and 2ab = y - element_init(e0, p->x->field); - element_init(e1, e0->field); - element_init(e2, e0->field); - element_square(e0, p->x); - element_square(e1, p->y); - element_mul(e1, e1, nqr); - element_sub(e0, e0, e1); - element_sqrt(e0, e0); - //e0 = sqrt(x^2 - nqr y^2) - element_add(e1, p->x, e0); - element_set_si(e2, 2); - element_invert(e2, e2); - element_mul(e1, e1, e2); - //e1 = (x + sqrt(x^2 - nqr y^2))/2 - if (!element_is_sqr(e1)) { - element_sub(e1, e1, e0); - //e1 should be a square - } - element_sqrt(e0, e1); - element_add(e1, e0, e0); - element_invert(e1, e1); - element_mul(r->y, p->y, e1); - element_set(r->x, e0); - element_clear(e0); - element_clear(e1); - element_clear(e2); -} - -static int fq_item_count(element_ptr e) { - UNUSED_VAR(e); - return 2; -} - -static element_ptr fq_item(element_ptr e, int i) { - eptr p = e->data; - switch(i) { - case 0: - return p->x; - case 1: - return p->y; - default: - return NULL; - } -} - -static void field_clear_fq(field_ptr f) { - UNUSED_VAR(f); - //f->order gets cleared automatically -} - -static void fq_out_info(FILE *out, field_ptr f) { - field_ptr fbase = f->data; - element_fprintf(out, "extension x^2 + %B, base field: ", fq_nqr(f)); - field_out_info(out, fbase); -} - -// Specialized versions of some of the above for the case K[i]. - -static void fi_mul(element_ptr n, element_ptr a, element_ptr b) { - eptr p = a->data; - eptr q = b->data; - eptr r = n->data; - element_t e0, e1, e2; - - element_init(e0, p->x->field); - element_init(e1, e0->field); - element_init(e2, e0->field); - /* Naive method: - element_mul(e0, p->x, q->x); - element_mul(e1, p->y, q->y); - element_sub(e0, e0, e1); - element_mul(e1, p->x, q->y); - element_mul(e2, p->y, q->x); - element_add(e1, e1, e2); - element_set(r->x, e0); - element_set(r->y, e1); - */ - // Karatsuba multiplicaiton: - element_add(e0, p->x, p->y); - element_add(e1, q->x, q->y); - element_mul(e2, e0, e1); - element_mul(e0, p->x, q->x); - element_sub(e2, e2, e0); - element_mul(e1, p->y, q->y); - element_sub(r->x, e0, e1); - element_sub(r->y, e2, e1); - - element_clear(e0); - element_clear(e1); - element_clear(e2); -} - -static void fi_square(element_ptr n, element_ptr a) { - eptr p = a->data; - eptr r = n->data; - element_t e0, e1; - - element_init(e0, p->x->field); - element_init(e1, e0->field); - // Re(n) = x^2 - y^2 = (x+y)(x-y) - element_add(e0, p->x, p->y); - element_sub(e1, p->x, p->y); - element_mul(e0, e0, e1); - // Im(n) = 2xy - element_mul(e1, p->x, p->y); - element_add(e1, e1, e1); - element_set(r->x, e0); - element_set(r->y, e1); - element_clear(e0); - element_clear(e1); -} - -static void fi_invert(element_ptr n, element_ptr a) { - eptr p = a->data; - eptr r = n->data; - element_t e0, e1; - - element_init(e0, p->x->field); - element_init(e1, e0->field); - element_square(e0, p->x); - element_square(e1, p->y); - element_add(e0, e0, e1); - element_invert(e0, e0); - element_mul(r->x, p->x, e0); - element_neg(e0, e0); - element_mul(r->y, p->y, e0); - - element_clear(e0); - element_clear(e1); -} - -static int fi_is_sqr(element_ptr e) { - // x + yi is a square <=> x^2 + y^2 is (in the base field). - - // Proof: (=>) if x+yi = (a+bi)^2, then a^2 - b^2 = x, 2ab = y, - // thus (a^2 + b^2)^2 = (a^2 - b^2)^2 + (2ab)^2 = x^2 + y^2 - - // (<=) Suppose A^2 = x^2 + y^2. If there exist a, b satisfying: - // a^2 = (+-A + x)/2, b^2 = (+-A - x)/2 - // then (a + bi)^2 = x + yi. - // - // We show that exactly one of (A + x)/2, (-A + x)/2 is a quadratic residue - // (thus a, b do exist). Suppose not. Then the product (x^2 - A^2) / 4 is - // some quadratic residue, a contradiction since this would imply x^2 - A^2 = - // -y^2 is also a quadratic residue, but we know -1 is not a quadratic - // residue. QED. - eptr p = e->data; - element_t e0, e1; - int result; - element_init(e0, p->x->field); - element_init(e1, e0->field); - element_square(e0, p->x); - element_square(e1, p->y); - element_add(e0, e0, e1); - result = element_is_sqr(e0); - element_clear(e0); - element_clear(e1); - return result; -} - -static void fi_sqrt(element_ptr n, element_ptr e) { - eptr p = e->data; - eptr r = n->data; - element_t e0, e1, e2; - - // If (a+bi)^2 = x+yi then 2a^2 = x +- sqrt(x^2 + y^2) - // where we choose the sign so that a exists, and 2ab = y. - // Thus 2b^2 = - (x -+ sqrt(x^2 + y^2)). - element_init(e0, p->x->field); - element_init(e1, e0->field); - element_init(e2, e0->field); - element_square(e0, p->x); - element_square(e1, p->y); - element_add(e0, e0, e1); - element_sqrt(e0, e0); - // e0 = sqrt(x^2 + y^2) - element_add(e1, p->x, e0); - element_set_si(e2, 2); - element_invert(e2, e2); - element_mul(e1, e1, e2); - // e1 = (x + sqrt(x^2 + y^2))/2 - if (!element_is_sqr(e1)) { - element_sub(e1, e1, e0); - // e1 should be a square. - } - element_sqrt(e0, e1); - element_add(e1, e0, e0); - element_invert(e1, e1); - element_mul(r->y, p->y, e1); - element_set(r->x, e0); - element_clear(e0); - element_clear(e1); - element_clear(e2); -} - -static void fi_out_info(FILE *out, field_ptr f) { - field_ptr fbase = f->data; - fprintf(out, "extension x^2 + 1, base field: "); - field_out_info(out, fbase); -} - -static void field_clear_fi(field_ptr f) { - UNUSED_VAR(f); -} - -// All the above should be static. - -void element_field_to_quadratic(element_ptr r, element_ptr a) { - eptr p = r->data; - element_set(p->x, a); - element_set0(p->y); -} - -void element_field_to_fi(element_ptr a, element_ptr b) { - element_field_to_quadratic(a, b); -} - -static element_ptr fq_get_x(element_ptr a) { - return ((eptr) a->data)->x; -} - -static element_ptr fq_get_y(element_ptr a) { - return ((eptr) a->data)->y; -} - -void field_init_quadratic(field_ptr f, field_ptr fbase) { - field_init(f); - - f->field_clear = field_clear_fq; - f->data = fbase; - - f->init = fq_init; - f->clear = fq_clear; - f->set_si = fq_set_si; - f->set_mpz = fq_set_mpz; - f->to_mpz = fq_to_mpz; - f->out_str = fq_out_str; - f->snprint = fq_snprint; - f->set_multiz = fq_set_multiz; - f->set_str = fq_set_str; - f->sign = fq_sign; - f->add = fq_add; - f->sub = fq_sub; - f->set = fq_set; - f->mul = fq_mul; - f->mul_mpz = fq_mul_mpz; - f->mul_si = fq_mul_si; - f->square = fq_square; - f->doub = fq_double; - f->neg = fq_neg; - f->cmp = fq_cmp; - f->invert = fq_invert; - f->random = fq_random; - f->from_hash = fq_from_hash; - f->is1 = fq_is1; - f->is0 = fq_is0; - f->set0 = fq_set0; - f->set1 = fq_set1; - f->is_sqr = fq_is_sqr; - f->sqrt = fq_sqrt; - f->to_bytes = fq_to_bytes; - f->from_bytes = fq_from_bytes; - f->out_info = fq_out_info; - f->item_count = fq_item_count; - f->item = fq_item; - f->get_x = fq_get_x; - f->get_y = fq_get_y; - - mpz_mul(f->order, fbase->order, fbase->order); - if (fbase->fixed_length_in_bytes < 0) { - f->length_in_bytes = fq_length_in_bytes; - f->fixed_length_in_bytes = -1; - } else { - f->fixed_length_in_bytes = 2 * fbase->fixed_length_in_bytes; - } -} - -void field_init_fi(field_ptr f, field_ptr fbase) { - field_init(f); - f->field_clear = field_clear_fi; - f->data = fbase; - f->init = fq_init; - f->clear = fq_clear; - f->set_si = fq_set_si; - f->set_mpz = fq_set_mpz; - f->to_mpz = fq_to_mpz; - f->out_str = fq_out_str; - f->snprint = fq_snprint; - f->set_multiz = fq_set_multiz; - f->set_str = fq_set_str; - f->sign = fq_sign; - f->add = fq_add; - f->sub = fq_sub; - f->set = fq_set; - f->mul = fi_mul; - f->mul_mpz = fq_mul_mpz; - f->mul_si = fq_mul_si; - f->square = fi_square; - f->doub = fq_double; - f->neg = fq_neg; - f->cmp = fq_cmp; - f->invert = fi_invert; - f->random = fq_random; - f->from_hash = fq_from_hash; - f->is1 = fq_is1; - f->is0 = fq_is0; - f->set0 = fq_set0; - f->set1 = fq_set1; - f->is_sqr = fi_is_sqr; - f->sqrt = fi_sqrt; - f->to_bytes = fq_to_bytes; - f->from_bytes = fq_from_bytes; - f->out_info = fi_out_info; - f->item_count = fq_item_count; - f->item = fq_item; - f->get_x = fq_get_x; - f->get_y = fq_get_y; - - mpz_mul(f->order, fbase->order, fbase->order); - if (fbase->fixed_length_in_bytes < 0) { - f->length_in_bytes = fq_length_in_bytes; - f->fixed_length_in_bytes = -1; - } else { - f->fixed_length_in_bytes = 2 * fbase->fixed_length_in_bytes; - } -} |