mirror of
https://github.com/oxen-io/lokinet.git
synced 2024-11-19 09:25:28 +00:00
115 lines
2.5 KiB
C
115 lines
2.5 KiB
C
/*
|
|
This file is adapted from ref10/scalarmult.c:
|
|
The code for Mongomery ladder is replace by the ladder assembly function;
|
|
Inversion is done in the same way as amd64-51/.
|
|
(fe is first converted into fe51 after Mongomery ladder)
|
|
*/
|
|
|
|
#include <stddef.h>
|
|
|
|
#ifdef HAVE_AVX_ASM
|
|
|
|
#include "utils.h"
|
|
#include "curve25519_sandy2x.h"
|
|
#include "../scalarmult_curve25519.h"
|
|
#include "fe.h"
|
|
#include "fe51.h"
|
|
#include "ladder.h"
|
|
#include "ladder_base.h"
|
|
|
|
#define x1 var[0]
|
|
#define x2 var[1]
|
|
#define z2 var[2]
|
|
|
|
static int
|
|
crypto_scalarmult_curve25519_sandy2x(unsigned char *q, const unsigned char *n,
|
|
const unsigned char *p)
|
|
{
|
|
unsigned char *t = q;
|
|
fe var[3];
|
|
fe51 x_51;
|
|
fe51 z_51;
|
|
unsigned int i;
|
|
|
|
for (i = 0; i < 32; i++) {
|
|
t[i] = n[i];
|
|
}
|
|
t[0] &= 248;
|
|
t[31] &= 127;
|
|
t[31] |= 64;
|
|
|
|
fe_frombytes(x1, p);
|
|
|
|
ladder(var, t);
|
|
|
|
z_51.v[0] = (z2[1] << 26) + z2[0];
|
|
z_51.v[1] = (z2[3] << 26) + z2[2];
|
|
z_51.v[2] = (z2[5] << 26) + z2[4];
|
|
z_51.v[3] = (z2[7] << 26) + z2[6];
|
|
z_51.v[4] = (z2[9] << 26) + z2[8];
|
|
|
|
x_51.v[0] = (x2[1] << 26) + x2[0];
|
|
x_51.v[1] = (x2[3] << 26) + x2[2];
|
|
x_51.v[2] = (x2[5] << 26) + x2[4];
|
|
x_51.v[3] = (x2[7] << 26) + x2[6];
|
|
x_51.v[4] = (x2[9] << 26) + x2[8];
|
|
|
|
fe51_invert(&z_51, &z_51);
|
|
fe51_mul(&x_51, &x_51, &z_51);
|
|
fe51_pack(q, &x_51);
|
|
|
|
return 0;
|
|
}
|
|
|
|
#undef x2
|
|
#undef z2
|
|
|
|
#define x2 var[0]
|
|
#define z2 var[1]
|
|
|
|
static int
|
|
crypto_scalarmult_curve25519_sandy2x_base(unsigned char *q,
|
|
const unsigned char *n)
|
|
{
|
|
unsigned char *t = q;
|
|
fe var[3];
|
|
fe51 x_51;
|
|
fe51 z_51;
|
|
unsigned int i;
|
|
|
|
for (i = 0;i < 32; i++) {
|
|
t[i] = n[i];
|
|
}
|
|
t[0] &= 248;
|
|
t[31] &= 127;
|
|
t[31] |= 64;
|
|
|
|
ladder_base(var, t);
|
|
|
|
z_51.v[0] = (z2[1] << 26) + z2[0];
|
|
z_51.v[1] = (z2[3] << 26) + z2[2];
|
|
z_51.v[2] = (z2[5] << 26) + z2[4];
|
|
z_51.v[3] = (z2[7] << 26) + z2[6];
|
|
z_51.v[4] = (z2[9] << 26) + z2[8];
|
|
|
|
x_51.v[0] = (x2[1] << 26) + x2[0];
|
|
x_51.v[1] = (x2[3] << 26) + x2[2];
|
|
x_51.v[2] = (x2[5] << 26) + x2[4];
|
|
x_51.v[3] = (x2[7] << 26) + x2[6];
|
|
x_51.v[4] = (x2[9] << 26) + x2[8];
|
|
|
|
fe51_invert(&z_51, &z_51);
|
|
fe51_mul(&x_51, &x_51, &z_51);
|
|
fe51_pack(q, &x_51);
|
|
|
|
return 0;
|
|
}
|
|
|
|
struct crypto_scalarmult_curve25519_implementation
|
|
crypto_scalarmult_curve25519_sandy2x_implementation = {
|
|
SODIUM_C99(.mult = ) crypto_scalarmult_curve25519_sandy2x,
|
|
SODIUM_C99(.mult_base = ) crypto_scalarmult_curve25519_sandy2x_base
|
|
};
|
|
|
|
#endif
|