coelner/gnuk
1
0
Fork 0
mirror of https://salsa.debian.org/gnuk-team/gnuk/gnuk.git synced 2024-09-21 03:10:08 +00:00
Code Issues Packages Projects Releases Wiki Activity

ecdsa

Browse Source
This commit is contained in:
NIIBE Yutaka 2011-10-12 18:07:52 +09:00
parent d6dc964536
commit fb97562fdc
3 changed files with 61 additions and 0 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

1
src/bn.h
View File

@ -16,3 +16,4 @@ uint32_t bn256_shift (bn256 *X, const bn256 *A, int shift);
int bn256_is_zero (const bn256 *X);
int bn256_is_even (const bn256 *X);
int bn256_is_ge (const bn256 *A, const bn256 *B);
void bn256_random (bn256 *X);

57
src/ec_p256.c
View File

@ -7,6 +7,7 @@
#include "bn.h"
#include "modp256.h"
#include "jpc-ac.h"
#include "mod.h"
#if 0
/*
@ -245,3 +246,59 @@ calculate_kG (ac *X, const bn256 *K)
jpc_to_ac (X, Q);
}
/*
* N: order of G
*/
static const bn256 N[1] = {
{{ 0xfc632551, 0xf3b9cac2, 0xa7179e84, 0xbce6faad,
0xffffffff, 0xffffffff, 0x00000000, 0xffffffff }}
};
/*
* MU = 2^512 / N
* MU = ( (1 << 256) | MU_lower )
*/
static const bn256 MU_lower[1] = {
{{ 0xeedf9bfe, 0x012ffd85, 0xdf1a6c21, 0x43190552,
0xffffffff, 0xfffffffe, 0xffffffff, 0x00000000 }}
};
/**
* @brief Compute signature (r,s) of hash string z with secret key dA
*/
void
ecdsa (bn256 *r, bn256 *s, const bn256 *z, const bn256 *d)
{
bn256 k[1];
ac KG[1];
bn512 tmp[1];
bn256 k_inv[1];
uint32_t carry;
do
{
do
{
bn256_random (k);
calculate_kG (KG, k);
if (bn256_is_ge (KG->x, N))
bn256_sub (r, KG->x, N);
else
memcpy (r, KG->x, sizeof (bn256));
}
while (bn256_is_zero (r));
mod_inv (k_inv, k, N);
bn256_mul (tmp, r, d);
mod_reduce (s, tmp, N, MU_lower);
carry = bn256_add (s, s, z);
if (carry)
bn256_sub (s, s, N);
bn256_mul (tmp, s, k_inv);
mod_reduce (s, tmp, N, MU_lower);
}
while (bn256_is_zero (s));
}

3
src/ec_p256.h Normal file
View File

@ -0,0 +1,3 @@
void calculate_kG (ac *X, const bn256 *K);
void ecdsa (bn256 *r, bn256 *s, const bn256 *z, const bn256 *d);