diff options
author | WuKong <rebirthmonkey@gmail.com> | 2015-09-04 09:25:34 +0200 |
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committer | WuKong <rebirthmonkey@gmail.com> | 2015-09-04 09:25:34 +0200 |
commit | 3baeb11a8fbcfcdbc31976d421f17b85503b3ecd (patch) | |
tree | 04891d88c1127148f1b390b5a24414e85b270aee /moon-abe/pbc-0.5.14/arith/fasterfp.c | |
parent | 67c5b73910f5fc437429c356978081b252a59480 (diff) |
init attribute-based encryption
Change-Id: Iba1a3d722110abf747a0fba366f3ebc911d25b25
Diffstat (limited to 'moon-abe/pbc-0.5.14/arith/fasterfp.c')
-rw-r--r-- | moon-abe/pbc-0.5.14/arith/fasterfp.c | 546 |
1 files changed, 546 insertions, 0 deletions
diff --git a/moon-abe/pbc-0.5.14/arith/fasterfp.c b/moon-abe/pbc-0.5.14/arith/fasterfp.c new file mode 100644 index 00000000..5ce8243a --- /dev/null +++ b/moon-abe/pbc-0.5.14/arith/fasterfp.c @@ -0,0 +1,546 @@ +// Naive implementation of F_p. +// It uses lowlevel GMP routines (mpn_* functions) like fastfp.c, but also +// has a flag for the value 0, avoiding many memsets. +// +// I'm thinking of using the flag to also represent 1, -1, +// but that complicates the logic even more, and I believe I need more +// control than GMP is willing to give in order to avoid expensive +// checks for 1, -1 everywhere. +// +// NOTE: does not work for moduli of the form: +// 2^(something * 8 * sizeof(mp_limb_t)) +// See comments in add, double code. +// (This kind of integer mod ring deserves its own implementation anyway.) + +#include <stdarg.h> +#include <stdio.h> +#include <stdint.h> // for intptr_t +#include <stdlib.h> +#include <string.h> +#include <gmp.h> +#include "pbc_utils.h" +#include "pbc_field.h" +#include "pbc_random.h" +#include "pbc_fp.h" +#include "pbc_memory.h" + +struct fp_field_data_s { + size_t limbs; + size_t bytes; + mp_limb_t *primelimbs; +}; +typedef struct fp_field_data_s fp_field_data_t[1]; +typedef struct fp_field_data_s *fp_field_data_ptr; + +struct data_s { + int flag; + mp_limb_t *d; +}; +typedef struct data_s *dataptr; + +static void fp_init(element_ptr e) { + fp_field_data_ptr p = e->field->data; + dataptr dp = e->data = pbc_malloc(sizeof(struct data_s)); + dp->flag = 0; + dp->d = pbc_malloc(p->bytes); +} + +static void fp_clear(element_ptr e) { + dataptr dp = e->data; + pbc_free(dp->d); + pbc_free(e->data); +} + +//assumes z is nonzero +static inline void from_mpz(element_ptr e, mpz_ptr z) { + fp_field_data_ptr p = e->field->data; + size_t count; + dataptr dp = e->data; + mpz_export(dp->d, &count, -1, sizeof(mp_limb_t), 0, 0, z); + memset((void *) (((unsigned char *) dp->d) + count * sizeof(mp_limb_t)), + 0, (p->limbs - count) * sizeof(mp_limb_t)); +} + +static void fp_set_mpz(element_ptr e, mpz_ptr z) { + dataptr dp = e->data; + if (!mpz_sgn(z)) { + dp->flag = 0; + } else { + mpz_t tmp; + mpz_init(tmp); + mpz_mod(tmp, z, e->field->order); + from_mpz(e, tmp); + mpz_clear(tmp); + dp->flag = 2; + } +} + +static void fp_set_si(element_ptr e, signed long int op) { + dataptr dp = e->data; + if (!op) { + dp->flag = 0; + } else { + const fp_field_data_ptr p = e->field->data; + const size_t t = p->limbs; + if (op < 0) { + mpn_sub_1(dp->d, p->primelimbs, t, -op); + } else { + dp->d[0] = op; + memset(&dp->d[1], 0, sizeof(mp_limb_t) * (t - 1)); + } + dp->flag = 2; + } +} + +static void fp_to_mpz(mpz_ptr z, element_ptr e) { + dataptr dp = e->data; + if (!dp->flag) { + mpz_set_ui(z, 0); + } else { + fp_field_data_ptr p = e->field->data; + mpz_import(z, p->limbs, -1, sizeof(mp_limb_t), 0, 0, dp->d); + } +} + +static void fp_set0(element_ptr e) { + dataptr dp = e->data; + dp->flag = 0; +} + +static void fp_set1(element_ptr e) { + fp_field_data_ptr p = e->field->data; + dataptr dp = e->data; + dp->flag = 2; + memset(&dp->d[1], 0, p->bytes - sizeof(mp_limb_t)); + dp->d[0] = 1; +} + +static int fp_is1(element_ptr e) { + dataptr dp = e->data; + if (!dp->flag) return 0; + else { + fp_field_data_ptr p = e->field->data; + size_t i, t = p->limbs; + if (dp->d[0] != 1) return 0; + for (i = 1; i < t; i++) if (dp->d[i]) return 0; + return 1; + } +} + +static int fp_is0(element_ptr e) { + dataptr dp = e->data; + return !dp->flag; +} + +static size_t fp_out_str(FILE * stream, int base, element_ptr e) { + size_t result; + mpz_t z; + mpz_init(z); + fp_to_mpz(z, e); + result = mpz_out_str(stream, base, z); + mpz_clear(z); + return result; +} + +static void fp_set(element_ptr c, element_ptr a) { + dataptr ad = a->data; + dataptr cd = c->data; + if (a == c) return; + if (!ad->flag) { + cd->flag = 0; + } else { + fp_field_data_ptr p = a->field->data; + + //Assembly is faster here, but I don't want to stoop to that level. + //Instead of calling slower memcpy, wrap stuff so that GMP assembly + //gets called. + /* + memcpy(cd->d, ad->d, p->bytes); + */ + mpz_t z1, z2; + z1->_mp_d = cd->d; + z2->_mp_d = ad->d; + z1->_mp_size = z1->_mp_alloc = z2->_mp_size = z2->_mp_alloc = p->limbs; + mpz_set(z1, z2); + + cd->flag = 2; + } +} + +static void fp_add(element_ptr c, element_ptr a, element_ptr b) { + dataptr ad = a->data, bd = b->data; + + if (!ad->flag) { + fp_set(c, b); + } else if (!bd->flag) { + fp_set(c, a); + } else { + dataptr cd = c->data; + fp_field_data_ptr p = a->field->data; + const size_t t = p->limbs; + mp_limb_t carry; + carry = mpn_add_n(cd->d, ad->d, bd->d, t); + + if (carry) { + //assumes result of following sub is not zero, + //i.e. modulus cannot be 2^(n * bits_per_limb) + mpn_sub_n(cd->d, cd->d, p->primelimbs, t); + cd->flag = 2; + } else { + int i = mpn_cmp(cd->d, p->primelimbs, t); + if (!i) { + cd->flag = 0; + } else { + cd->flag = 2; + if (i > 0) { + mpn_sub_n(cd->d, cd->d, p->primelimbs, t); + } + } + } + } +} + +static void fp_double(element_ptr c, element_ptr a) { + dataptr ad = a->data, cd = c->data; + if (!ad->flag) { + cd->flag = 0; + } else { + fp_field_data_ptr p = c->field->data; + const size_t t = p->limbs; + if (mpn_lshift(cd->d, ad->d, t, 1)) { + cd->flag = 2; + //again, assumes result is not zero: + mpn_sub_n(cd->d, cd->d, p->primelimbs, t); + } else { + int i = mpn_cmp(cd->d, p->primelimbs, t); + if (!i) { + cd->flag = 0; + } else { + cd->flag = 2; + if (i > 0) { + mpn_sub_n(cd->d, cd->d, p->primelimbs, t); + } + } + } + } +} + +static void fp_halve(element_ptr c, element_ptr a) { + dataptr ad = a->data, cd = c->data; + if (!ad->flag) { + cd->flag = 0; + } else { + fp_field_data_ptr p = c->field->data; + const size_t t = p->limbs; + int carry = 0; + mp_limb_t *alimb = ad->d; + mp_limb_t *climb = cd->d; + if (alimb[0] & 1) { + carry = mpn_add_n(climb, alimb, p->primelimbs, t); + } else fp_set(c, a); + + mpn_rshift(climb, climb, t, 1); + if (carry) climb[t - 1] |= ((mp_limb_t) 1) << (sizeof(mp_limb_t) * 8 - 1); + } +} + +static void fp_neg(element_ptr c, element_ptr a) { + dataptr ad = a->data, cd = c->data; + if (!ad->flag) cd->flag = 0; + else { + fp_field_data_ptr p = a->field->data; + mpn_sub_n(cd->d, p->primelimbs, ad->d, p->limbs); + cd->flag = 2; + } +} + +static void fp_sub(element_ptr c, element_ptr a, element_ptr b) { + dataptr ad = a->data, bd = b->data; + + if (!ad->flag) { + fp_neg(c, b); + } else if (!bd->flag) { + fp_set(c, a); + } else { + fp_field_data_ptr p = c->field->data; + size_t t = p->limbs; + dataptr cd = c->data; + int i = mpn_cmp(ad->d, bd->d, t); + + if (i == 0) { + cd->flag = 0; + } else { + cd->flag = 2; + mpn_sub_n(cd->d, ad->d, bd->d, t); + if (i < 0) { + mpn_add_n(cd->d, cd->d, p->primelimbs, t); + } + } + } +} + +static void fp_mul(element_ptr c, element_ptr a, element_ptr b) { + dataptr ad = a->data, bd = b->data; + dataptr cd = c->data; + + if (!ad->flag || !bd->flag) { + cd->flag = 0; + } else { + fp_field_data_ptr p = c->field->data; + size_t t = p->limbs; + //mp_limb_t tmp[3 * t + 1]; + //mp_limb_t *qp = &tmp[2 * t]; + mp_limb_t tmp[2 * t]; + mp_limb_t qp[t + 1]; + //static mp_limb_t tmp[2 * 100]; + //static mp_limb_t qp[100 + 1]; + + mpn_mul_n(tmp, ad->d, bd->d, t); + + mpn_tdiv_qr(qp, cd->d, 0, tmp, 2 * t, p->primelimbs, t); + cd->flag = 2; + } +} + +static void fp_square(element_ptr c, element_ptr a) { + const fp_field_data_ptr p = c->field->data; + mpz_t z1, z2; + size_t diff; + dataptr ad = a->data; + dataptr cd = c->data; + + if (!ad->flag) { + cd->flag = 0; + } else { + cd->flag = 2; + z1->_mp_d = cd->d; + z1->_mp_size = z1->_mp_alloc = p->limbs; + if (c == a) { + mpz_powm_ui(z1, z1, 2, c->field->order); + } else { + z2->_mp_d = ad->d; + z2->_mp_size = z2->_mp_alloc = p->limbs; + mpz_powm_ui(z1, z2, 2, c->field->order); + } + + diff = p->limbs - z1->_mp_size; + if (diff) memset(&z1->_mp_d[z1->_mp_size], 0, diff * sizeof(mp_limb_t)); + + //mpn_sqr_n() might make the code below faster than the code above + //but GMP doesn't expose this function + /* + const fp_field_data_ptr p = c->field->data; + const size_t t = p->limbs; + mp_limb_t tmp[2 * t]; + mp_limb_t qp[t + 1]; + + mpn_mul_n(tmp, ad->d, ad->d, t); + + mpn_tdiv_qr(qp, cd->d, 0, tmp, 2 * t, p->primelimbs, t); + */ + } +} + +static void fp_mul_si(element_ptr c, element_ptr a, signed long int op) { + dataptr ad = a->data; + dataptr cd = c->data; + + if (!ad->flag || !op) { + cd->flag = 0; + } else { + cd->flag = 2; + fp_field_data_ptr p = a->field->data; + size_t t = p->limbs; + mp_limb_t tmp[t + 1]; + mp_limb_t qp[2]; + + tmp[t] = mpn_mul_1(tmp, ad->d, t, labs(op)); + mpn_tdiv_qr(qp, cd->d, 0, tmp, t + 1, p->primelimbs, t); + if (op < 0) { //TODO: don't need to check c != 0 this time + fp_neg(c, c); + } + } +} + +static void fp_pow_mpz(element_ptr c, element_ptr a, mpz_ptr op) { + dataptr ad = a->data; + dataptr cd = c->data; + if (!ad->flag) cd->flag = 0; + else { + mpz_t z; + mpz_init(z); + fp_to_mpz(z, a); + mpz_powm(z, z, op, a->field->order); + from_mpz(c, z); + mpz_clear(z); + cd->flag = 2; + } +} + +static void fp_invert(element_ptr c, element_ptr a) { + //assumes a is invertible + dataptr cd = c->data; + mpz_t z; + mpz_init(z); + fp_to_mpz(z, a); + mpz_invert(z, z, a->field->order); + from_mpz(c, z); + mpz_clear(z); + cd->flag = 2; +} + +static void fp_random(element_ptr a) { + dataptr ad = a->data; + mpz_t z; + mpz_init(z); + pbc_mpz_random(z, a->field->order); + if (mpz_sgn(z)) { + from_mpz(a, z); + ad->flag = 2; + } else { + ad->flag = 0; + } + mpz_clear(z); +} + +static void fp_from_hash(element_ptr a, void *data, int len) { + mpz_t z; + + mpz_init(z); + pbc_mpz_from_hash(z, a->field->order, data, len); + fp_set_mpz(a, z); + mpz_clear(z); +} + +static int fp_cmp(element_ptr a, element_ptr b) { + dataptr ad = a->data, bd = b->data; + if (!ad->flag) { + return bd->flag; + } else { + fp_field_data_ptr p = a->field->data; + return mpn_cmp(ad->d, bd->d, p->limbs); + //return memcmp(ad->d, bd->d, p->limbs); + } +} + +static int fp_sgn_odd(element_ptr a) { + dataptr ad = a->data; + if (!ad->flag) return 0; + return ad->d[0] & 1 ? 1 : -1; +} + +static int fp_sgn_even(element_ptr a) { + fp_field_data_ptr p = a->field->data; + dataptr ad = a->data; + if (!ad->flag) return 0; + mp_limb_t sum[p->limbs]; + + int carry = mpn_add_n(sum, ad->d, ad->d, p->limbs); + if (carry) return 1; + return mpn_cmp(sum, p->primelimbs, p->limbs); +} + + +static int fp_is_sqr(element_ptr a) { + dataptr ad = a->data; + int res; + mpz_t z; + mpz_init(z); + //0 is a square + if (!ad->flag) return 1; + fp_to_mpz(z, a); + res = mpz_legendre(z, a->field->order) == 1; + mpz_clear(z); + return res; +} + +static int fp_to_bytes(unsigned char *data, element_t a) { + dataptr ad = a->data; + int n = a->field->fixed_length_in_bytes; + if (!ad->flag) { + memset(data, 0, n); + } else { + mpz_t z; + + mpz_init(z); + fp_to_mpz(z, a); + pbc_mpz_out_raw_n(data, n, z); + mpz_clear(z); + } + return n; +} + +static int fp_from_bytes(element_t a, unsigned char *data) { + dataptr ad = a->data; + int n; + mpz_t z; + + mpz_init(z); + + n = a->field->fixed_length_in_bytes; + mpz_import(z, n, 1, 1, 1, 0, data); + if (!mpz_sgn(z)) ad->flag = 0; + else { + ad->flag = 2; + from_mpz(a, z); + } + mpz_clear(z); + return n; +} + +static void fp_out_info(FILE* str, field_ptr f) { + element_fprintf(str, "GF(%Zd): zero flag + mpn", f->order); +} + +static void fp_field_clear(field_t f) { + fp_field_data_ptr p = f->data; + pbc_free(p->primelimbs); + pbc_free(p); +} + +void field_init_faster_fp(field_ptr f, mpz_t prime) { + PBC_ASSERT(!mpz_fits_ulong_p(prime), "modulus too small"); + fp_field_data_ptr p; + field_init(f); + f->init = fp_init; + f->clear = fp_clear; + f->set_si = fp_set_si; + f->set_mpz = fp_set_mpz; + f->out_str = fp_out_str; + f->add = fp_add; + f->sub = fp_sub; + f->set = fp_set; + f->mul = fp_mul; + f->mul_si = fp_mul_si; + f->square = fp_square; + f->doub = fp_double; + f->halve = fp_halve; + f->pow_mpz = fp_pow_mpz; + f->neg = fp_neg; + f->cmp = fp_cmp; + f->sign = mpz_odd_p(prime) ? fp_sgn_odd : fp_sgn_even; + f->invert = fp_invert; + f->random = fp_random; + f->from_hash = fp_from_hash; + f->is1 = fp_is1; + f->is0 = fp_is0; + f->set0 = fp_set0; + f->set1 = fp_set1; + f->is_sqr = fp_is_sqr; + f->sqrt = element_tonelli; + f->field_clear = fp_field_clear; + f->to_bytes = fp_to_bytes; + f->from_bytes = fp_from_bytes; + f->to_mpz = fp_to_mpz; + + f->out_info = fp_out_info; + + p = f->data = pbc_malloc(sizeof(fp_field_data_t)); + p->limbs = mpz_size(prime); + p->bytes = p->limbs * sizeof(mp_limb_t); + p->primelimbs = pbc_malloc(p->bytes); + mpz_export(p->primelimbs, &p->limbs, -1, sizeof(mp_limb_t), 0, 0, prime); + + mpz_set(f->order, prime); + f->fixed_length_in_bytes = (mpz_sizeinbase(prime, 2) + 7) / 8; +} |