hasufell/pqc
1
0
Fork 0
Code Issues Pull Requests Releases Wiki Activity

Merge branch 'poly'

Browse Source
This commit is contained in:
hasufell 2014-04-20 19:58:22 +02:00
commit ae01f6e3cf
No known key found for this signature in database
GPG Key ID: 220CD1C5BDEED020
5 changed files with 188 additions and 41 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

4
src/Makefile
View File

@ -37,8 +37,8 @@ endif
LIBS += -L.
# objects
PQC_OBJS = rand.o poly.o
PQC_HEADERS = err.h rand.h poly.h context.h
PQC_OBJS = rand.o poly.o keypair.o mem.o
PQC_HEADERS = err.h rand.h poly.h context.h keypair.h
# CUNIT_OBJS = cunit.o
# includes

48
src/mem.c Normal file
View File

@ -0,0 +1,48 @@
/*
* Copyright (C) 2014 FH Bielefeld
*
* This file is part of a FH Bielefeld project.
*
* This library is free software; you can redistribute it and/or
* modify it under the terms of the GNU Lesser General Public
* License as published by the Free Software Foundation; either
* version 2.1 of the License, or (at your option) any later version.
*
* This library is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public
* License along with this library; if not, write to the Free Software
* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston,
* MA 02110-1301 USA
*/
#include "mem.h"
#include <stdio.h>
#include <stdlib.h>
/**
* Allocate memory of size and return
* a void pointer.
*
* @param size of the memory to allocate in bytes
* @return void pointer to the beginning of the allocated memory block
*/
void *ntru_malloc(size_t size)
{
void *ptr;
ptr = malloc(size);
if (size)
if (!ptr) {
fprintf(stderr, "failed to allocate memory, aborting!");
abort();
}
return ptr;
}

29
src/mem.h Normal file
View File

@ -0,0 +1,29 @@
/*
* Copyright (C) 2014 FH Bielefeld
*
* This file is part of a FH Bielefeld project.
*
* This library is free software; you can redistribute it and/or
* modify it under the terms of the GNU Lesser General Public
* License as published by the Free Software Foundation; either
* version 2.1 of the License, or (at your option) any later version.
*
* This library is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public
* License along with this library; if not, write to the Free Software
* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston,
* MA 02110-1301 USA
*/
#ifndef NTRU_MEM_H
#define NTRU_MEM_H
#include <stdlib.h>
void *ntru_malloc(size_t size);
#endif /* NTRU_MEM_H */

119
src/poly.c
View File

@ -21,8 +21,10 @@
#include "context.h"
#include "err.h"
#include "mem.h"
#include "poly.h"
#include <stdarg.h>
#include <stdbool.h>
#include <stdio.h>
#include <tompoly.h>
@ -34,6 +36,9 @@
* static declarations
*/
static unsigned int get_degree(pb_poly const * const poly);
static void pb_mod2_to_modq(pb_poly * const a,
pb_poly *Fq,
ntru_context *ctx);
/**
@ -108,7 +113,7 @@ pb_poly *build_polynom(int const * const c,
pb_poly *new_poly;
mp_int chara;
new_poly = malloc(sizeof(*new_poly));
new_poly = ntru_malloc(sizeof(*new_poly));
init_integer(&chara);
init_polynom_size(new_poly, &chara, len);
mp_clear(&chara);
@ -126,14 +131,14 @@ pb_poly *build_polynom(int const * const c,
unsigned_c = c[i];
}
mp_set_int(&(new_poly->terms[i]), unsigned_c);
MP_SET_INT(&(new_poly->terms[i]), unsigned_c);
if (sign == true)
mp_neg(&(new_poly->terms[i]), &(new_poly->terms[i]));
}
} else { /* fill with zeros */
for (unsigned int i = 0; i < len; i++)
mp_set(&(new_poly->terms[i]), 0);
MP_SET(&(new_poly->terms[i]), 0);
}
new_poly->used = len;
@ -150,7 +155,7 @@ pb_poly *build_polynom(int const * const c,
void erase_polynom(pb_poly *poly, size_t len)
{
for (unsigned int i = 0; i < len ; i++) {
mp_set(&(poly->terms[i]), 0);
MP_SET(&(poly->terms[i]), 0);
mp_abs(&(poly->terms[i]), &(poly->terms[i]));
}
}
@ -169,6 +174,30 @@ void delete_polynom(pb_poly *poly)
free(poly);
}
/**
* This deletes the internal structure of all polynomials,
* and frees the pointers. Don't call this on stack variables,
* this is intended for use after ntru_ functions, that
* return a polynomial pointer.
* You must call this with NULL as last argument!
*
* @param poly the polynomial to delete
* @param ... follow up polynomials
*/
void delete_polynom_multi(pb_poly *poly, ...)
{
pb_poly *next_poly;
va_list args;
next_poly = poly;
va_start(args, poly);
while (next_poly != NULL) {
delete_polynom(next_poly);
next_poly = va_arg(args, pb_poly*);
}
va_end(args);
}
/**
* Starmultiplication, as follows:
* c = a * b mod (x^N − 1)
@ -189,7 +218,7 @@ void pb_starmultiply(pb_poly *a,
mp_int mp_modulus;
init_integer(&mp_modulus);
mp_set_int(&mp_modulus, (unsigned long)(modulus));
MP_SET_INT(&mp_modulus, (unsigned long)(modulus));
/* avoid side effects */
a_tmp = build_polynom(NULL, ctx->N, ctx);
@ -257,6 +286,43 @@ static unsigned int get_degree(pb_poly const * const poly)
return count;
}
/**
* Find the inverse polynomial modulo a power of 2,
* which is q.
*
* @param a polynomial to invert (is allowed to be the same as param Fq)
* @param Fq polynomial [out]
* @param ctx NTRU context
* @return true/false for success/failure
*/
static void pb_mod2_to_modq(pb_poly * const a,
pb_poly *Fq,
ntru_context *ctx)
{
int v = 2;
while (v < (int)(ctx->q)) {
pb_poly *pb_tmp,
*pb_tmp2;
mp_int tmp_v;
pb_tmp = build_polynom(NULL, ctx->N, ctx);
v = v * 2;
init_integer(&tmp_v);
MP_SET_INT(&tmp_v, v);
pb_tmp2 = build_polynom(NULL, ctx->N, ctx);
MP_SET_INT(&(pb_tmp2->terms[0]), 2);
/* mod after sub or before? */
pb_starmultiply(a, Fq, pb_tmp, ctx, v);
PB_SUB(pb_tmp2, pb_tmp, pb_tmp);
PB_MOD(pb_tmp, &tmp_v, pb_tmp, ctx->N);
pb_starmultiply(Fq, pb_tmp, Fq, ctx, v);
mp_clear(&tmp_v);
delete_polynom_multi(pb_tmp, pb_tmp2, NULL);
}
}
/**
* Invert the polynomial a modulo q.
*
@ -270,19 +336,18 @@ bool pb_inverse_poly_q(pb_poly * const a,
ntru_context *ctx)
{
int k = 0,
j = 0,
v = 2;
j = 0;
pb_poly *a_tmp, *b, *c, *f, *g;
b = build_polynom(NULL, ctx->N + 1, ctx);
mp_set(&(b->terms[0]), 1);
MP_SET(&(b->terms[0]), 1);
c = build_polynom(NULL, ctx->N + 1, ctx);
f = build_polynom(NULL, ctx->N + 1, ctx);
PB_COPY(a, f);
g = build_polynom(NULL, ctx->N + 1, ctx);
mp_set(&(g->terms[0]), 1);
MP_SET(&(g->terms[0]), 1);
mp_neg(&(g->terms[0]), &(g->terms[0]));
mp_set(&(g->terms[ctx->N]), 1);
MP_SET(&(g->terms[ctx->N]), 1);
/* avoid side effects */
a_tmp = build_polynom(NULL, ctx->N, ctx);
PB_COPY(a, a_tmp);
@ -294,8 +359,8 @@ bool pb_inverse_poly_q(pb_poly * const a,
MP_COPY(&(f->terms[i]), &(f->terms[i - 1]));
MP_COPY(&(c->terms[ctx->N - i]), &(c->terms[ctx->N + 1 - i]));
}
mp_set(&(f->terms[ctx->N]), 0);
mp_set(&(c->terms[0]), 0);
MP_SET(&(f->terms[ctx->N]), 0);
MP_SET(&(c->terms[0]), 0);
k++;
}
@ -321,42 +386,18 @@ OUT_OF_LOOP:
MP_COPY(&(b->terms[i]), &(Fq->terms[j]));
}
while (v < (int)(ctx->q)) {
pb_poly *pb_tmp,
*pb_tmp2;
mp_int tmp_v;
pb_tmp = build_polynom(NULL, ctx->N, ctx);
v = v * 2;
init_integer(&tmp_v);
mp_set_int(&tmp_v, v);
pb_tmp2 = build_polynom(NULL, ctx->N, ctx);
mp_set_int(&(pb_tmp2->terms[0]), 2);
/* hope this does not blow up in our face */
pb_starmultiply(a_tmp, Fq, pb_tmp, ctx, v);
PB_SUB(pb_tmp2, pb_tmp, pb_tmp);
PB_MOD(pb_tmp, &tmp_v, pb_tmp, ctx->N);
pb_starmultiply(Fq, pb_tmp, Fq, ctx, v);
mp_clear(&tmp_v);
delete_polynom(pb_tmp);
delete_polynom(pb_tmp2);
}
pb_mod2_to_modq(a_tmp, Fq, ctx);
for (int i = ctx->N - 1; i >= 0; i--)
if (mp_cmp_d(&(Fq->terms[i]), 0) == MP_LT) {
mp_int mp_tmp;
init_integer(&mp_tmp);
mp_set_int(&mp_tmp, ctx->q);
MP_SET_INT(&mp_tmp, ctx->q);
MP_ADD(&(Fq->terms[i]), &mp_tmp, &(Fq->terms[i]));
mp_clear(&mp_tmp);
}
delete_polynom(a_tmp);
delete_polynom(b);
delete_polynom(c);
delete_polynom(f);
delete_polynom(g);
delete_polynom_multi(a_tmp, b, c, f, g, NULL);
/* TODO: check if the f * Fq = 1 (mod p) condition holds true */

29
src/poly.h
View File

@ -28,8 +28,19 @@
#include <tompoly.h>
#include <tommath.h>
#include <stdarg.h>
#include <stdbool.h>
#define MP_SET(...) mp_set(__VA_ARGS__)
#define MP_SET_INT(...) \
{ \
int result; \
if ((result = mp_set_int(__VA_ARGS__)) != MP_OKAY) \
NTRU_ABORT("Error setting long constant. %s", \
mp_error_to_string(result)); \
}
#define MP_MUL(...) \
{ \
int result; \
@ -86,6 +97,22 @@
mp_error_to_string(result)); \
}
#define MP_EXPTMOD(...) \
{ \
int result; \
if ((result = mp_exptmod(__VA_ARGS__)) != MP_OKAY) \
NTRU_ABORT("Error computing modular exponentiation. %s", \
mp_error_to_string(result)); \
}
#define MP_EXPT_D(...) \
{ \
int result; \
if ((result = mp_expt_d(__VA_ARGS__)) != MP_OKAY) \
NTRU_ABORT("Error computing modular exponentiation. %s", \
mp_error_to_string(result)); \
}
#define PB_MUL(...) \
{ \
int result; \
@ -138,6 +165,8 @@ void erase_polynom(pb_poly *poly, size_t len);
void delete_polynom(pb_poly *new_poly);
void delete_polynom_multi(pb_poly *poly, ...);
void pb_starmultiply(pb_poly *a,
pb_poly *b,
pb_poly *c,