OVMS3-idf/components/bt/bluedroid/stack/smp/p_256_ecc_pp.c
yulong 72eaaff9fe component/bt: Fixed the vulnerability released by Bluetooth org when using public key not check in the process of ECDH encryption.
1. Add the 100 times test when the private key is generated by the random number;
2. Add the bt components to the unit-test-app/config directory.
3. Added the bt unit test case to CI.
2018-08-13 14:08:11 +08:00

280 lines
9.3 KiB
C

/******************************************************************************
*
* Copyright (C) 2006-2015 Broadcom Corporation
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at:
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*
******************************************************************************/
/******************************************************************************
*
* This file contains simple pairing algorithms using Elliptic Curve Cryptography for private public key
*
******************************************************************************/
//#include <stdio.h>
//#include <stdlib.h>
#include <string.h>
#include "p_256_ecc_pp.h"
#include "p_256_multprecision.h"
elliptic_curve_t curve;
elliptic_curve_t curve_p256;
static void p_256_init_point(Point *q)
{
memset(q, 0, sizeof(Point));
}
static void p_256_copy_point(Point *q, Point *p)
{
memcpy(q, p, sizeof(Point));
}
// q=2q
static void ECC_Double(Point *q, Point *p, uint32_t keyLength)
{
DWORD t1[KEY_LENGTH_DWORDS_P256];
DWORD t2[KEY_LENGTH_DWORDS_P256];
DWORD t3[KEY_LENGTH_DWORDS_P256];
DWORD *x1;
DWORD *x3;
DWORD *y1;
DWORD *y3;
DWORD *z1;
DWORD *z3;
if (multiprecision_iszero(p->z, keyLength)) {
multiprecision_init(q->z, keyLength);
return; // return infinity
}
x1 = p->x; y1 = p->y; z1 = p->z;
x3 = q->x; y3 = q->y; z3 = q->z;
multiprecision_mersenns_squa_mod(t1, z1, keyLength); // t1=z1^2
multiprecision_sub_mod(t2, x1, t1, keyLength); // t2=x1-t1
multiprecision_add_mod(t1, x1, t1, keyLength); // t1=x1+t1
multiprecision_mersenns_mult_mod(t2, t1, t2, keyLength); // t2=t2*t1
multiprecision_lshift_mod(t3, t2, keyLength);
multiprecision_add_mod(t2, t3, t2, keyLength); // t2=3t2
multiprecision_mersenns_mult_mod(z3, y1, z1, keyLength); // z3=y1*z1
multiprecision_lshift_mod(z3, z3, keyLength);
multiprecision_mersenns_squa_mod(y3, y1, keyLength); // y3=y1^2
multiprecision_lshift_mod(y3, y3, keyLength);
multiprecision_mersenns_mult_mod(t3, y3, x1, keyLength); // t3=y3*x1=x1*y1^2
multiprecision_lshift_mod(t3, t3, keyLength);
multiprecision_mersenns_squa_mod(y3, y3, keyLength); // y3=y3^2=y1^4
multiprecision_lshift_mod(y3, y3, keyLength);
multiprecision_mersenns_squa_mod(x3, t2, keyLength); // x3=t2^2
multiprecision_lshift_mod(t1, t3, keyLength); // t1=2t3
multiprecision_sub_mod(x3, x3, t1, keyLength); // x3=x3-t1
multiprecision_sub_mod(t1, t3, x3, keyLength); // t1=t3-x3
multiprecision_mersenns_mult_mod(t1, t1, t2, keyLength); // t1=t1*t2
multiprecision_sub_mod(y3, t1, y3, keyLength); // y3=t1-y3
}
// q=q+p, zp must be 1
static void ECC_Add(Point *r, Point *p, Point *q, uint32_t keyLength)
{
DWORD t1[KEY_LENGTH_DWORDS_P256];
DWORD t2[KEY_LENGTH_DWORDS_P256];
DWORD *x1;
DWORD *x2;
DWORD *x3;
DWORD *y1;
DWORD *y2;
DWORD *y3;
DWORD *z1;
DWORD *z2;
DWORD *z3;
x1 = p->x; y1 = p->y; z1 = p->z;
x2 = q->x; y2 = q->y; z2 = q->z;
x3 = r->x; y3 = r->y; z3 = r->z;
// if Q=infinity, return p
if (multiprecision_iszero(z2, keyLength)) {
p_256_copy_point(r, p);
return;
}
// if P=infinity, return q
if (multiprecision_iszero(z1, keyLength)) {
p_256_copy_point(r, q);
return;
}
multiprecision_mersenns_squa_mod(t1, z1, keyLength); // t1=z1^2
multiprecision_mersenns_mult_mod(t2, z1, t1, keyLength); // t2=t1*z1
multiprecision_mersenns_mult_mod(t1, x2, t1, keyLength); // t1=t1*x2
multiprecision_mersenns_mult_mod(t2, y2, t2, keyLength); // t2=t2*y2
multiprecision_sub_mod(t1, t1, x1, keyLength); // t1=t1-x1
multiprecision_sub_mod(t2, t2, y1, keyLength); // t2=t2-y1
if (multiprecision_iszero(t1, keyLength)) {
if (multiprecision_iszero(t2, keyLength)) {
ECC_Double(r, q, keyLength) ;
return;
} else {
multiprecision_init(z3, keyLength);
return; // return infinity
}
}
multiprecision_mersenns_mult_mod(z3, z1, t1, keyLength); // z3=z1*t1
multiprecision_mersenns_squa_mod(y3, t1, keyLength); // t3=t1^2
multiprecision_mersenns_mult_mod(z1, y3, t1, keyLength); // t4=t3*t1
multiprecision_mersenns_mult_mod(y3, y3, x1, keyLength); // t3=t3*x1
multiprecision_lshift_mod(t1, y3, keyLength); // t1=2*t3
multiprecision_mersenns_squa_mod(x3, t2, keyLength); // x3=t2^2
multiprecision_sub_mod(x3, x3, t1, keyLength); // x3=x3-t1
multiprecision_sub_mod(x3, x3, z1, keyLength); // x3=x3-t4
multiprecision_sub_mod(y3, y3, x3, keyLength); // t3=t3-x3
multiprecision_mersenns_mult_mod(y3, y3, t2, keyLength); // t3=t3*t2
multiprecision_mersenns_mult_mod(z1, z1, y1, keyLength); // t4=t4*t1
multiprecision_sub_mod(y3, y3, z1, keyLength);
}
// Computing the Non-Adjacent Form of a positive integer
static void ECC_NAF(uint8_t *naf, uint32_t *NumNAF, DWORD *k, uint32_t keyLength)
{
uint32_t sign;
int i = 0;
int j;
uint32_t var;
while ((var = multiprecision_most_signbits(k, keyLength)) >= 1) {
if (k[0] & 0x01) { // k is odd
sign = (k[0] & 0x03); // 1 or 3
// k = k-naf[i]
if (sign == 1) {
k[0] = k[0] & 0xFFFFFFFE;
} else {
k[0] = k[0] + 1;
if (k[0] == 0) { //overflow
j = 1;
do {
k[j]++;
} while (k[j++] == 0); //overflow
}
}
} else {
sign = 0;
}
multiprecision_rshift(k, k, keyLength);
naf[i / 4] |= (sign) << ((i % 4) * 2);
i++;
}
*NumNAF = i;
}
// Binary Non-Adjacent Form for point multiplication
void ECC_PointMult_Bin_NAF(Point *q, Point *p, DWORD *n, uint32_t keyLength)
{
uint32_t sign;
UINT8 naf[256 / 4 + 1];
uint32_t NumNaf;
Point minus_p;
Point r;
DWORD *modp;
if (keyLength == KEY_LENGTH_DWORDS_P256) {
modp = curve_p256.p;
} else {
modp = curve.p;
}
p_256_init_point(&r);
multiprecision_init(p->z, keyLength);
p->z[0] = 1;
// initialization
p_256_init_point(q);
// -p
multiprecision_copy(minus_p.x, p->x, keyLength);
multiprecision_sub(minus_p.y, modp, p->y, keyLength);
multiprecision_init(minus_p.z, keyLength);
minus_p.z[0] = 1;
// NAF
memset(naf, 0, sizeof(naf));
ECC_NAF(naf, &NumNaf, n, keyLength);
for (int i = NumNaf - 1; i >= 0; i--) {
p_256_copy_point(&r, q);
ECC_Double(q, &r, keyLength);
sign = (naf[i / 4] >> ((i % 4) * 2)) & 0x03;
if (sign == 1) {
p_256_copy_point(&r, q);
ECC_Add(q, &r, p, keyLength);
} else if (sign == 3) {
p_256_copy_point(&r, q);
ECC_Add(q, &r, &minus_p, keyLength);
}
}
multiprecision_inv_mod(minus_p.x, q->z, keyLength);
multiprecision_mersenns_squa_mod(q->z, minus_p.x, keyLength);
multiprecision_mersenns_mult_mod(q->x, q->x, q->z, keyLength);
multiprecision_mersenns_mult_mod(q->z, q->z, minus_p.x, keyLength);
multiprecision_mersenns_mult_mod(q->y, q->y, q->z, keyLength);
}
bool ECC_CheckPointIsInElliCur_P256(Point *p)
{
/* y^2 % q */
DWORD y_y_q[KEY_LENGTH_DWORDS_P256] = {0x0};
/* x^2 % q */
DWORD x_x_q[KEY_LENGTH_DWORDS_P256] = {0x0};
/* x % q */
DWORD x_q[KEY_LENGTH_DWORDS_P256] = {0x0};
/* x^2, To prevent overflow, the length of the x square here needs to
be expanded to two times the original one. */
DWORD x_x[2*KEY_LENGTH_DWORDS_P256] = {0x0};
/* y_y_q =(p->y)^2(mod q) */
multiprecision_mersenns_squa_mod(y_y_q, p->y, KEY_LENGTH_DWORDS_P256);
/* Calculate the value of p->x square, x_x = (p->x)^2 */
multiprecision_mult(x_x, p->x, p->x, KEY_LENGTH_DWORDS_P256);
/* The function of the elliptic curve is y^2 = x^3 - 3x + b (mod q) ==>
y^2 = (x^2 - 3)*x + b (mod q),
so we calculate the x^2 - 3 value here */
x_x[0] -= 3;
/* Using math relations. (a*b) % q = ((a%q)*(b%q)) % q ==>
(x^2 - 3)*x = (((x^2 - 3) % q) * x % q) % q */
multiprecision_fast_mod_P256(x_x_q, x_x);
/* x_x = x_x_q * x_q */
multiprecision_mult(x_x, x_x_q, p->x, KEY_LENGTH_DWORDS_P256);
/* x_q = x_x % q */
multiprecision_fast_mod_P256(x_q, x_x);
/* Save the result in x_x_q */
multiprecision_add_mod(x_x_q, x_q, curve_p256.b, KEY_LENGTH_DWORDS_P256);
/* compare the y_y_q and x_x_q, see if they are on a given elliptic curve. */
if (multiprecision_compare(y_y_q, x_x_q, KEY_LENGTH_DWORDS_P256)) {
return false;
} else {
return true;
}
}