beda11a079
The X25519 implementation comes from libsodium. Explicit copyright notices have been added to each file as well as some portability changes (e.g. align.h).
175 lines
4.5 KiB
C
175 lines
4.5 KiB
C
/*
|
|
* ISC License
|
|
*
|
|
* Copyright (c) 2013-2019
|
|
* Frank Denis <j at pureftpd dot org>
|
|
*
|
|
* Permission to use, copy, modify, and/or distribute this software for any
|
|
* purpose with or without fee is hereby granted, provided that the above
|
|
* copyright notice and this permission notice appear in all copies.
|
|
*
|
|
* THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
|
|
* WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
|
|
* MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
|
|
* ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
|
|
* WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
|
|
* ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
|
|
* OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
|
|
*/
|
|
|
|
#ifndef ed25519_ref10_H
|
|
#define ed25519_ref10_H
|
|
|
|
#include <roken.h>
|
|
#include <stddef.h>
|
|
#include <stdint.h>
|
|
|
|
/*
|
|
fe means field element.
|
|
Here the field is \Z/(2^255-19).
|
|
*/
|
|
|
|
#ifdef HAVE_TI_MODE
|
|
typedef uint64_t fe25519[5];
|
|
#else
|
|
typedef int32_t fe25519[10];
|
|
#endif
|
|
|
|
void fe25519_invert(fe25519 out, const fe25519 z);
|
|
void fe25519_frombytes(fe25519 h, const unsigned char *s);
|
|
void fe25519_tobytes(unsigned char *s, const fe25519 h);
|
|
|
|
static inline int
|
|
sodium_is_zero(const unsigned char *n, const size_t nlen)
|
|
{
|
|
size_t i;
|
|
volatile unsigned char d = 0U;
|
|
|
|
for (i = 0U; i < nlen; i++) {
|
|
d |= n[i];
|
|
}
|
|
return 1 & ((d - 1) >> 8);
|
|
}
|
|
|
|
#ifdef HAVE_TI_MODE
|
|
# include "ed25519_ref10_fe_51.h"
|
|
#else
|
|
# include "ed25519_ref10_fe_25_5.h"
|
|
#endif
|
|
|
|
|
|
/*
|
|
ge means group element.
|
|
|
|
Here the group is the set of pairs (x,y) of field elements
|
|
satisfying -x^2 + y^2 = 1 + d x^2y^2
|
|
where d = -121665/121666.
|
|
|
|
Representations:
|
|
ge25519_p2 (projective): (X:Y:Z) satisfying x=X/Z, y=Y/Z
|
|
ge25519_p3 (extended): (X:Y:Z:T) satisfying x=X/Z, y=Y/Z, XY=ZT
|
|
ge25519_p1p1 (completed): ((X:Z),(Y:T)) satisfying x=X/Z, y=Y/T
|
|
ge25519_precomp (Duif): (y+x,y-x,2dxy)
|
|
*/
|
|
|
|
typedef struct {
|
|
fe25519 X;
|
|
fe25519 Y;
|
|
fe25519 Z;
|
|
} ge25519_p2;
|
|
|
|
typedef struct {
|
|
fe25519 X;
|
|
fe25519 Y;
|
|
fe25519 Z;
|
|
fe25519 T;
|
|
} ge25519_p3;
|
|
|
|
typedef struct {
|
|
fe25519 X;
|
|
fe25519 Y;
|
|
fe25519 Z;
|
|
fe25519 T;
|
|
} ge25519_p1p1;
|
|
|
|
typedef struct {
|
|
fe25519 yplusx;
|
|
fe25519 yminusx;
|
|
fe25519 xy2d;
|
|
} ge25519_precomp;
|
|
|
|
typedef struct {
|
|
fe25519 YplusX;
|
|
fe25519 YminusX;
|
|
fe25519 Z;
|
|
fe25519 T2d;
|
|
} ge25519_cached;
|
|
|
|
void ge25519_tobytes(unsigned char *s, const ge25519_p2 *h);
|
|
|
|
void ge25519_p3_tobytes(unsigned char *s, const ge25519_p3 *h);
|
|
|
|
int ge25519_frombytes(ge25519_p3 *h, const unsigned char *s);
|
|
|
|
int ge25519_frombytes_negate_vartime(ge25519_p3 *h, const unsigned char *s);
|
|
|
|
void ge25519_p3_to_cached(ge25519_cached *r, const ge25519_p3 *p);
|
|
|
|
void ge25519_p1p1_to_p2(ge25519_p2 *r, const ge25519_p1p1 *p);
|
|
|
|
void ge25519_p1p1_to_p3(ge25519_p3 *r, const ge25519_p1p1 *p);
|
|
|
|
void ge25519_add(ge25519_p1p1 *r, const ge25519_p3 *p, const ge25519_cached *q);
|
|
|
|
void ge25519_sub(ge25519_p1p1 *r, const ge25519_p3 *p, const ge25519_cached *q);
|
|
|
|
void ge25519_scalarmult_base(ge25519_p3 *h, const unsigned char *a);
|
|
|
|
void ge25519_double_scalarmult_vartime(ge25519_p2 *r, const unsigned char *a,
|
|
const ge25519_p3 *A,
|
|
const unsigned char *b);
|
|
|
|
void ge25519_scalarmult(ge25519_p3 *h, const unsigned char *a,
|
|
const ge25519_p3 *p);
|
|
|
|
int ge25519_is_canonical(const unsigned char *s);
|
|
|
|
int ge25519_is_on_curve(const ge25519_p3 *p);
|
|
|
|
int ge25519_is_on_main_subgroup(const ge25519_p3 *p);
|
|
|
|
int ge25519_has_small_order(const unsigned char s[32]);
|
|
|
|
void ge25519_from_uniform(unsigned char s[32], const unsigned char r[32]);
|
|
|
|
void ge25519_from_hash(unsigned char s[32], const unsigned char h[64]);
|
|
|
|
/*
|
|
Ristretto group
|
|
*/
|
|
|
|
int ristretto255_frombytes(ge25519_p3 *h, const unsigned char *s);
|
|
|
|
void ristretto255_p3_tobytes(unsigned char *s, const ge25519_p3 *h);
|
|
|
|
void ristretto255_from_hash(unsigned char s[32], const unsigned char h[64]);
|
|
|
|
/*
|
|
The set of scalars is \Z/l
|
|
where l = 2^252 + 27742317777372353535851937790883648493.
|
|
*/
|
|
|
|
void sc25519_invert(unsigned char recip[32], const unsigned char s[32]);
|
|
|
|
void sc25519_reduce(unsigned char s[64]);
|
|
|
|
void sc25519_mul(unsigned char s[32], const unsigned char a[32],
|
|
const unsigned char b[32]);
|
|
|
|
void sc25519_muladd(unsigned char s[32], const unsigned char a[32],
|
|
const unsigned char b[32], const unsigned char c[32]);
|
|
|
|
int sc25519_is_canonical(const unsigned char s[32]);
|
|
|
|
#endif
|