694 lines
20 KiB
C
Vendored
694 lines
20 KiB
C
Vendored
/*
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* Copyright 2023-2026 The OpenSSL Project Authors. All Rights Reserved.
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*
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* Licensed under the Apache License 2.0 (the "License"). You may not use
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* this file except in compliance with the License. You can obtain a copy
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* in the file LICENSE in the source distribution or at
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* https://www.openssl.org/source/license.html
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*
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*/
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/*
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* SM2 low level APIs are deprecated for public use, but still ok for
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* internal use.
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*/
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#include "internal/deprecated.h"
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#include <string.h>
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#include <openssl/err.h>
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#include "crypto/bn.h"
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#include "ec_local.h"
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#include "internal/common.h"
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#include "internal/constant_time.h"
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#define P256_LIMBS (256 / BN_BITS2)
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#if !defined(OPENSSL_NO_SM2_PRECOMP)
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extern const BN_ULONG ecp_sm2p256_precomputed[8 * 32 * 256];
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#endif
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typedef struct {
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BN_ULONG X[P256_LIMBS];
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BN_ULONG Y[P256_LIMBS];
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BN_ULONG Z[P256_LIMBS];
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} P256_POINT;
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typedef struct {
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BN_ULONG X[P256_LIMBS];
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BN_ULONG Y[P256_LIMBS];
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} P256_POINT_AFFINE;
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#if !defined(OPENSSL_NO_SM2_PRECOMP)
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/* Coordinates of G, for which we have precomputed tables */
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ALIGN32 static const BN_ULONG def_xG[P256_LIMBS] = {
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0x715a4589334c74c7, 0x8fe30bbff2660be1,
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0x5f9904466a39c994, 0x32c4ae2c1f198119
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};
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ALIGN32 static const BN_ULONG def_yG[P256_LIMBS] = {
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0x02df32e52139f0a0, 0xd0a9877cc62a4740, 0x59bdcee36b692153, 0xbc3736a2f4f6779c
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};
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#endif
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/* p and order for SM2 according to GB/T 32918.5-2017 */
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ALIGN32 static const BN_ULONG def_p[P256_LIMBS] = {
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0xffffffffffffffff, 0xffffffff00000000,
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0xffffffffffffffff, 0xfffffffeffffffff
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};
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ALIGN32 static const BN_ULONG ONE[P256_LIMBS] = { 1, 0, 0, 0 };
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/* Functions implemented in assembly */
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/*
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* Most of below mentioned functions *preserve* the property of inputs
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* being fully reduced, i.e. being in [0, modulus) range. Simply put if
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* inputs are fully reduced, then output is too.
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*/
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/* Right shift: a >> 1 */
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void bn_rshift1(BN_ULONG *a);
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/* Sub: r = a - b */
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void bn_sub(BN_ULONG *r, const BN_ULONG *a, const BN_ULONG *b);
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/* Modular div by 2: r = a / 2 mod p */
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void ecp_sm2p256_div_by_2(BN_ULONG *r, const BN_ULONG *a);
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/* Modular div by 2: r = a / 2 mod n, where n = ord(p) */
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void ecp_sm2p256_div_by_2_mod_ord(BN_ULONG *r, const BN_ULONG *a);
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/* Modular add: r = a + b mod p */
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void ecp_sm2p256_add(BN_ULONG *r, const BN_ULONG *a, const BN_ULONG *b);
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/* Modular sub: r = a - b mod p */
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void ecp_sm2p256_sub(BN_ULONG *r, const BN_ULONG *a, const BN_ULONG *b);
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/* Modular sub: r = a - b mod n, where n = ord(p) */
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void ecp_sm2p256_sub_mod_ord(BN_ULONG *r, const BN_ULONG *a, const BN_ULONG *b);
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/* Modular mul by 3: out = 3 * a mod p */
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void ecp_sm2p256_mul_by_3(BN_ULONG *r, const BN_ULONG *a);
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/* Modular mul: r = a * b mod p */
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void ecp_sm2p256_mul(BN_ULONG *r, const BN_ULONG *a, const BN_ULONG *b);
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/* Modular sqr: r = a ^ 2 mod p */
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void ecp_sm2p256_sqr(BN_ULONG *r, const BN_ULONG *a);
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static ossl_inline BN_ULONG is_zeros(const BN_ULONG *a)
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{
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BN_ULONG res;
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res = a[0] | a[1] | a[2] | a[3];
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return constant_time_is_zero_64(res);
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}
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static ossl_inline int is_equal(const BN_ULONG *a, const BN_ULONG *b)
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{
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BN_ULONG res;
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res = a[0] ^ b[0];
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res |= a[1] ^ b[1];
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res |= a[2] ^ b[2];
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res |= a[3] ^ b[3];
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return constant_time_is_zero_64(res);
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}
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static ossl_inline int is_greater(const BN_ULONG *a, const BN_ULONG *b)
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{
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int i;
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for (i = P256_LIMBS - 1; i >= 0; --i) {
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if (a[i] > b[i])
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return 1;
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if (a[i] < b[i])
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return -1;
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}
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return 0;
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}
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#define is_one(a) is_equal(a, ONE)
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#define is_even(a) !(a[0] & 1)
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#define is_point_equal(a, b) \
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is_equal(a->X, b->X) && is_equal(a->Y, b->Y) && is_equal(a->Z, b->Z)
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/* Bignum and field elements conversion */
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#define ecp_sm2p256_bignum_field_elem(out, in) \
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bn_copy_words(out, in, P256_LIMBS)
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/* Binary algorithm for inversion in Fp */
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#define BN_MOD_INV(out, in, mod_div, mod_sub, mod) \
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do { \
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ALIGN32 BN_ULONG u[4]; \
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ALIGN32 BN_ULONG v[4]; \
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ALIGN32 BN_ULONG x1[4] = { 1, 0, 0, 0 }; \
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ALIGN32 BN_ULONG x2[4] = { 0 }; \
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\
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if (is_zeros(in)) \
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return; \
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memcpy(u, in, 32); \
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memcpy(v, mod, 32); \
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while (!is_one(u) && !is_one(v)) { \
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while (is_even(u)) { \
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bn_rshift1(u); \
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mod_div(x1, x1); \
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} \
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while (is_even(v)) { \
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bn_rshift1(v); \
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mod_div(x2, x2); \
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} \
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if (is_greater(u, v) == 1) { \
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bn_sub(u, u, v); \
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mod_sub(x1, x1, x2); \
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} else { \
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bn_sub(v, v, u); \
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mod_sub(x2, x2, x1); \
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} \
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} \
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if (is_one(u)) \
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memcpy(out, x1, 32); \
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else \
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memcpy(out, x2, 32); \
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} while (0)
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/* Modular inverse |out| = |in|^(-1) mod |p|. */
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static ossl_inline void ecp_sm2p256_mod_inverse(BN_ULONG *out,
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const BN_ULONG *in)
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{
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BN_MOD_INV(out, in, ecp_sm2p256_div_by_2, ecp_sm2p256_sub, def_p);
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}
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/* Point double: R <- P + P */
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static void ecp_sm2p256_point_double(P256_POINT *R, const P256_POINT *P)
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{
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unsigned int i;
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ALIGN32 BN_ULONG tmp0[P256_LIMBS];
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ALIGN32 BN_ULONG tmp1[P256_LIMBS];
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ALIGN32 BN_ULONG tmp2[P256_LIMBS];
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/* zero-check P->Z */
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if (is_zeros(P->Z)) {
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for (i = 0; i < P256_LIMBS; ++i)
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R->Z[i] = 0;
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return;
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}
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ecp_sm2p256_sqr(tmp0, P->Z);
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ecp_sm2p256_sub(tmp1, P->X, tmp0);
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ecp_sm2p256_add(tmp0, P->X, tmp0);
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ecp_sm2p256_mul(tmp1, tmp1, tmp0);
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ecp_sm2p256_mul_by_3(tmp1, tmp1);
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ecp_sm2p256_add(R->Y, P->Y, P->Y);
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ecp_sm2p256_mul(R->Z, R->Y, P->Z);
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ecp_sm2p256_sqr(R->Y, R->Y);
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ecp_sm2p256_mul(tmp2, R->Y, P->X);
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ecp_sm2p256_sqr(R->Y, R->Y);
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ecp_sm2p256_div_by_2(R->Y, R->Y);
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ecp_sm2p256_sqr(R->X, tmp1);
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ecp_sm2p256_add(tmp0, tmp2, tmp2);
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ecp_sm2p256_sub(R->X, R->X, tmp0);
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ecp_sm2p256_sub(tmp0, tmp2, R->X);
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ecp_sm2p256_mul(tmp0, tmp0, tmp1);
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ecp_sm2p256_sub(tmp1, tmp0, R->Y);
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memcpy(R->Y, tmp1, 32);
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}
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/* Point add affine: R <- P + Q */
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static void ecp_sm2p256_point_add_affine(P256_POINT *R, const P256_POINT *P,
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const P256_POINT_AFFINE *Q)
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{
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unsigned int i;
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ALIGN32 BN_ULONG tmp0[P256_LIMBS] = { 0 };
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ALIGN32 BN_ULONG tmp1[P256_LIMBS] = { 0 };
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ALIGN32 BN_ULONG tmp2[P256_LIMBS] = { 0 };
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ALIGN32 BN_ULONG tmp3[P256_LIMBS] = { 0 };
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/* zero-check P->Z */
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if (is_zeros(P->Z)) {
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for (i = 0; i < P256_LIMBS; ++i) {
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R->X[i] = Q->X[i];
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R->Y[i] = Q->Y[i];
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R->Z[i] = 0;
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}
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R->Z[0] = 1;
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return;
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}
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ecp_sm2p256_sqr(tmp0, P->Z);
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ecp_sm2p256_mul(tmp1, tmp0, P->Z);
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ecp_sm2p256_mul(tmp0, tmp0, Q->X);
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ecp_sm2p256_mul(tmp1, tmp1, Q->Y);
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ecp_sm2p256_sub(tmp0, tmp0, P->X);
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ecp_sm2p256_sub(tmp1, tmp1, P->Y);
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/* zero-check tmp0, tmp1 */
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if (is_zeros(tmp0)) {
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if (is_zeros(tmp1)) {
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P256_POINT K;
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for (i = 0; i < P256_LIMBS; ++i) {
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K.X[i] = Q->X[i];
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K.Y[i] = Q->Y[i];
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K.Z[i] = 0;
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}
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K.Z[0] = 1;
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ecp_sm2p256_point_double(R, &K);
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} else {
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for (i = 0; i < P256_LIMBS; ++i)
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R->Z[i] = 0;
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}
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return;
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}
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ecp_sm2p256_mul(R->Z, P->Z, tmp0);
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ecp_sm2p256_sqr(tmp2, tmp0);
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ecp_sm2p256_mul(tmp3, tmp2, tmp0);
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ecp_sm2p256_mul(tmp2, tmp2, P->X);
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ecp_sm2p256_add(tmp0, tmp2, tmp2);
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ecp_sm2p256_sqr(R->X, tmp1);
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ecp_sm2p256_sub(R->X, R->X, tmp0);
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ecp_sm2p256_sub(R->X, R->X, tmp3);
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ecp_sm2p256_sub(tmp2, tmp2, R->X);
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ecp_sm2p256_mul(tmp2, tmp2, tmp1);
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ecp_sm2p256_mul(tmp3, tmp3, P->Y);
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ecp_sm2p256_sub(R->Y, tmp2, tmp3);
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}
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/* Point add: R <- P + Q */
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static void ecp_sm2p256_point_add(P256_POINT *R, const P256_POINT *P,
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const P256_POINT *Q)
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{
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unsigned int i;
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ALIGN32 BN_ULONG tmp0[P256_LIMBS] = { 0 };
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ALIGN32 BN_ULONG tmp1[P256_LIMBS] = { 0 };
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ALIGN32 BN_ULONG tmp2[P256_LIMBS] = { 0 };
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/* zero-check P | Q ->Z */
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if (is_zeros(P->Z)) {
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for (i = 0; i < P256_LIMBS; ++i) {
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R->X[i] = Q->X[i];
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R->Y[i] = Q->Y[i];
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R->Z[i] = Q->Z[i];
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}
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return;
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} else if (is_zeros(Q->Z)) {
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for (i = 0; i < P256_LIMBS; ++i) {
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R->X[i] = P->X[i];
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R->Y[i] = P->Y[i];
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R->Z[i] = P->Z[i];
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}
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return;
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} else if (is_point_equal(P, Q)) {
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ecp_sm2p256_point_double(R, Q);
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return;
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}
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ecp_sm2p256_sqr(tmp0, P->Z);
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ecp_sm2p256_mul(tmp1, tmp0, P->Z);
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ecp_sm2p256_mul(tmp0, tmp0, Q->X);
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ecp_sm2p256_mul(tmp1, tmp1, Q->Y);
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ecp_sm2p256_mul(R->Y, P->Y, Q->Z);
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ecp_sm2p256_mul(R->Z, Q->Z, P->Z);
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ecp_sm2p256_sqr(tmp2, Q->Z);
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ecp_sm2p256_mul(R->Y, tmp2, R->Y);
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ecp_sm2p256_mul(R->X, tmp2, P->X);
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ecp_sm2p256_sub(tmp0, tmp0, R->X);
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ecp_sm2p256_mul(R->Z, tmp0, R->Z);
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ecp_sm2p256_sub(tmp1, tmp1, R->Y);
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ecp_sm2p256_sqr(tmp2, tmp0);
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ecp_sm2p256_mul(tmp0, tmp0, tmp2);
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ecp_sm2p256_mul(tmp2, tmp2, R->X);
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ecp_sm2p256_sqr(R->X, tmp1);
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ecp_sm2p256_sub(R->X, R->X, tmp2);
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ecp_sm2p256_sub(R->X, R->X, tmp2);
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ecp_sm2p256_sub(R->X, R->X, tmp0);
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ecp_sm2p256_sub(tmp2, tmp2, R->X);
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ecp_sm2p256_mul(tmp2, tmp1, tmp2);
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ecp_sm2p256_mul(tmp0, tmp0, R->Y);
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ecp_sm2p256_sub(R->Y, tmp2, tmp0);
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}
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#if !defined(OPENSSL_NO_SM2_PRECOMP)
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/* Base point mul by scalar: k - scalar, G - base point */
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static void ecp_sm2p256_point_G_mul_by_scalar(P256_POINT *R, const BN_ULONG *k)
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{
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unsigned int i, index, mask = 0xff;
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P256_POINT_AFFINE Q;
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memset(R, 0, sizeof(P256_POINT));
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if (is_zeros(k))
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return;
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index = k[0] & mask;
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if (index) {
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index = index * 8;
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memcpy(R->X, ecp_sm2p256_precomputed + index, 32);
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memcpy(R->Y, ecp_sm2p256_precomputed + index + P256_LIMBS, 32);
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R->Z[0] = 1;
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}
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for (i = 1; i < 32; ++i) {
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index = (k[i / 8] >> (8 * (i % 8))) & mask;
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if (index) {
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index = index + i * 256;
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index = index * 8;
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memcpy(Q.X, ecp_sm2p256_precomputed + index, 32);
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memcpy(Q.Y, ecp_sm2p256_precomputed + index + P256_LIMBS, 32);
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ecp_sm2p256_point_add_affine(R, R, &Q);
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}
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}
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}
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#endif
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/*
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* Affine point mul by scalar: k - scalar, P - affine point
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*/
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static void ecp_sm2p256_point_P_mul_by_scalar(P256_POINT *R, const BN_ULONG *k,
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P256_POINT_AFFINE P)
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{
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int i, init = 0;
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unsigned int index, mask = 0x0f;
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ALIGN64 P256_POINT precomputed[16];
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memset(R, 0, sizeof(P256_POINT));
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if (is_zeros(k))
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return;
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/* The first value of the precomputed table is P. */
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memcpy(precomputed[1].X, P.X, 32);
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memcpy(precomputed[1].Y, P.Y, 32);
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precomputed[1].Z[0] = 1;
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precomputed[1].Z[1] = 0;
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precomputed[1].Z[2] = 0;
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precomputed[1].Z[3] = 0;
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/* The second value of the precomputed table is 2P. */
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ecp_sm2p256_point_double(&precomputed[2], &precomputed[1]);
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/* The subsequent elements are 3P, 4P, and so on. */
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for (i = 3; i < 16; ++i)
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ecp_sm2p256_point_add_affine(&precomputed[i], &precomputed[i - 1], &P);
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for (i = 64 - 1; i >= 0; --i) {
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index = (k[i / 16] >> (4 * (i % 16))) & mask;
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if (init == 0) {
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if (index) {
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memcpy(R, &precomputed[index], sizeof(P256_POINT));
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init = 1;
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}
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} else {
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ecp_sm2p256_point_double(R, R);
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ecp_sm2p256_point_double(R, R);
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ecp_sm2p256_point_double(R, R);
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ecp_sm2p256_point_double(R, R);
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if (index)
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ecp_sm2p256_point_add(R, R, &precomputed[index]);
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}
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}
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}
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/* Get affine point */
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static void ecp_sm2p256_point_get_affine(P256_POINT_AFFINE *R,
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const P256_POINT *P)
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{
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ALIGN32 BN_ULONG z_inv3[P256_LIMBS] = { 0 };
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ALIGN32 BN_ULONG z_inv2[P256_LIMBS] = { 0 };
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if (is_one(P->Z)) {
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memcpy(R->X, P->X, 32);
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memcpy(R->Y, P->Y, 32);
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return;
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}
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ecp_sm2p256_mod_inverse(z_inv3, P->Z);
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ecp_sm2p256_sqr(z_inv2, z_inv3);
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ecp_sm2p256_mul(R->X, P->X, z_inv2);
|
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ecp_sm2p256_mul(z_inv3, z_inv3, z_inv2);
|
||
ecp_sm2p256_mul(R->Y, P->Y, z_inv3);
|
||
}
|
||
|
||
#if !defined(OPENSSL_NO_SM2_PRECOMP)
|
||
static int ecp_sm2p256_is_affine_G(const EC_POINT *generator)
|
||
{
|
||
return (bn_get_top(generator->X) == P256_LIMBS)
|
||
&& (bn_get_top(generator->Y) == P256_LIMBS)
|
||
&& is_equal(bn_get_words(generator->X), def_xG)
|
||
&& is_equal(bn_get_words(generator->Y), def_yG)
|
||
&& (generator->Z_is_one == 1);
|
||
}
|
||
#endif
|
||
|
||
/* r = sum(scalar[i]*point[i]) */
|
||
static int ecp_sm2p256_windowed_mul(const EC_GROUP *group,
|
||
P256_POINT *r,
|
||
const BIGNUM **scalar,
|
||
const EC_POINT **point,
|
||
size_t num, BN_CTX *ctx)
|
||
{
|
||
unsigned int i;
|
||
int ret = 0;
|
||
const BIGNUM **scalars = NULL;
|
||
ALIGN32 BN_ULONG k[P256_LIMBS] = { 0 };
|
||
P256_POINT kP;
|
||
ALIGN32 union {
|
||
P256_POINT p;
|
||
P256_POINT_AFFINE a;
|
||
} t, p;
|
||
|
||
if (num > OPENSSL_MALLOC_MAX_NELEMS(P256_POINT)
|
||
|| (scalars = OPENSSL_malloc(num * sizeof(BIGNUM *))) == NULL) {
|
||
ECerr(ERR_LIB_EC, ERR_R_MALLOC_FAILURE);
|
||
goto err;
|
||
}
|
||
|
||
memset(r, 0, sizeof(P256_POINT));
|
||
|
||
for (i = 0; i < num; i++) {
|
||
if (EC_POINT_is_at_infinity(group, point[i]))
|
||
continue;
|
||
|
||
if ((BN_num_bits(scalar[i]) > 256) || BN_is_negative(scalar[i])) {
|
||
BIGNUM *tmp;
|
||
|
||
if ((tmp = BN_CTX_get(ctx)) == NULL)
|
||
goto err;
|
||
if (!BN_nnmod(tmp, scalar[i], group->order, ctx)) {
|
||
ECerr(ERR_LIB_EC, ERR_R_BN_LIB);
|
||
goto err;
|
||
}
|
||
scalars[i] = tmp;
|
||
} else {
|
||
scalars[i] = scalar[i];
|
||
}
|
||
|
||
if (ecp_sm2p256_bignum_field_elem(k, scalars[i]) <= 0
|
||
|| ecp_sm2p256_bignum_field_elem(p.p.X, point[i]->X) <= 0
|
||
|| ecp_sm2p256_bignum_field_elem(p.p.Y, point[i]->Y) <= 0
|
||
|| ecp_sm2p256_bignum_field_elem(p.p.Z, point[i]->Z) <= 0) {
|
||
ECerr(ERR_LIB_EC, EC_R_COORDINATES_OUT_OF_RANGE);
|
||
goto err;
|
||
}
|
||
|
||
ecp_sm2p256_point_get_affine(&t.a, &p.p);
|
||
ecp_sm2p256_point_P_mul_by_scalar(&kP, k, t.a);
|
||
ecp_sm2p256_point_add(r, r, &kP);
|
||
}
|
||
|
||
ret = 1;
|
||
err:
|
||
OPENSSL_free(scalars);
|
||
return ret;
|
||
}
|
||
|
||
/* r = scalar*G + sum(scalars[i]*points[i]) */
|
||
static int ecp_sm2p256_points_mul(const EC_GROUP *group,
|
||
EC_POINT *r,
|
||
const BIGNUM *scalar,
|
||
size_t num,
|
||
const EC_POINT *points[],
|
||
const BIGNUM *scalars[], BN_CTX *ctx)
|
||
{
|
||
int ret = 0, p_is_infinity = 0;
|
||
const EC_POINT *generator = NULL;
|
||
ALIGN32 BN_ULONG k[P256_LIMBS] = { 0 };
|
||
ALIGN32 union {
|
||
P256_POINT p;
|
||
P256_POINT_AFFINE a;
|
||
} t, p;
|
||
|
||
if ((num + 1) == 0 || (num + 1) > OPENSSL_MALLOC_MAX_NELEMS(void *)) {
|
||
ECerr(ERR_LIB_EC, ERR_R_MALLOC_FAILURE);
|
||
goto err;
|
||
}
|
||
|
||
BN_CTX_start(ctx);
|
||
|
||
if (scalar) {
|
||
generator = EC_GROUP_get0_generator(group);
|
||
if (generator == NULL) {
|
||
ECerr(ERR_LIB_EC, EC_R_UNDEFINED_GENERATOR);
|
||
goto err;
|
||
}
|
||
|
||
if (!ecp_sm2p256_bignum_field_elem(k, scalar)) {
|
||
ECerr(ERR_LIB_EC, EC_R_COORDINATES_OUT_OF_RANGE);
|
||
goto err;
|
||
}
|
||
#if !defined(OPENSSL_NO_SM2_PRECOMP)
|
||
if (ecp_sm2p256_is_affine_G(generator)) {
|
||
ecp_sm2p256_point_G_mul_by_scalar(&p.p, k);
|
||
} else
|
||
#endif
|
||
{
|
||
/* if no precomputed table */
|
||
const EC_POINT *new_generator[1];
|
||
const BIGNUM *g_scalars[1];
|
||
|
||
new_generator[0] = generator;
|
||
g_scalars[0] = scalar;
|
||
|
||
if (!ecp_sm2p256_windowed_mul(group, &p.p, g_scalars, new_generator,
|
||
(new_generator[0] != NULL
|
||
&& g_scalars[0] != NULL),
|
||
ctx))
|
||
goto err;
|
||
}
|
||
} else {
|
||
p_is_infinity = 1;
|
||
}
|
||
if (num) {
|
||
P256_POINT *out = &t.p;
|
||
|
||
if (p_is_infinity)
|
||
out = &p.p;
|
||
|
||
if (!ecp_sm2p256_windowed_mul(group, out, scalars, points, num, ctx))
|
||
goto err;
|
||
|
||
if (!p_is_infinity)
|
||
ecp_sm2p256_point_add(&p.p, &p.p, out);
|
||
}
|
||
|
||
/* Not constant-time, but we're only operating on the public output. */
|
||
if (!bn_set_words(r->X, p.p.X, P256_LIMBS)
|
||
|| !bn_set_words(r->Y, p.p.Y, P256_LIMBS)
|
||
|| !bn_set_words(r->Z, p.p.Z, P256_LIMBS))
|
||
goto err;
|
||
r->Z_is_one = is_equal(bn_get_words(r->Z), ONE) & 1;
|
||
|
||
ret = 1;
|
||
err:
|
||
BN_CTX_end(ctx);
|
||
return ret;
|
||
}
|
||
|
||
static int ecp_sm2p256_field_mul(const EC_GROUP *group, BIGNUM *r,
|
||
const BIGNUM *a, const BIGNUM *b, BN_CTX *ctx)
|
||
{
|
||
ALIGN32 BN_ULONG a_fe[P256_LIMBS] = { 0 };
|
||
ALIGN32 BN_ULONG b_fe[P256_LIMBS] = { 0 };
|
||
ALIGN32 BN_ULONG r_fe[P256_LIMBS] = { 0 };
|
||
|
||
if (a == NULL || b == NULL || r == NULL)
|
||
return 0;
|
||
|
||
if (!ecp_sm2p256_bignum_field_elem(a_fe, a)
|
||
|| !ecp_sm2p256_bignum_field_elem(b_fe, b)) {
|
||
ECerr(ERR_LIB_EC, EC_R_COORDINATES_OUT_OF_RANGE);
|
||
return 0;
|
||
}
|
||
|
||
ecp_sm2p256_mul(r_fe, a_fe, b_fe);
|
||
|
||
if (!bn_set_words(r, r_fe, P256_LIMBS))
|
||
return 0;
|
||
|
||
return 1;
|
||
}
|
||
|
||
static int ecp_sm2p256_field_sqr(const EC_GROUP *group, BIGNUM *r,
|
||
const BIGNUM *a, BN_CTX *ctx)
|
||
{
|
||
ALIGN32 BN_ULONG a_fe[P256_LIMBS] = { 0 };
|
||
ALIGN32 BN_ULONG r_fe[P256_LIMBS] = { 0 };
|
||
|
||
if (a == NULL || r == NULL)
|
||
return 0;
|
||
|
||
if (!ecp_sm2p256_bignum_field_elem(a_fe, a)) {
|
||
ECerr(ERR_LIB_EC, EC_R_COORDINATES_OUT_OF_RANGE);
|
||
return 0;
|
||
}
|
||
|
||
ecp_sm2p256_sqr(r_fe, a_fe);
|
||
|
||
if (!bn_set_words(r, r_fe, P256_LIMBS))
|
||
return 0;
|
||
|
||
return 1;
|
||
}
|
||
|
||
const EC_METHOD *EC_GFp_sm2p256_method(void)
|
||
{
|
||
static const EC_METHOD ret = {
|
||
EC_FLAGS_DEFAULT_OCT,
|
||
NID_X9_62_prime_field,
|
||
ossl_ec_GFp_simple_group_init,
|
||
ossl_ec_GFp_simple_group_finish,
|
||
ossl_ec_GFp_simple_group_clear_finish,
|
||
ossl_ec_GFp_simple_group_copy,
|
||
ossl_ec_GFp_simple_group_set_curve,
|
||
ossl_ec_GFp_simple_group_get_curve,
|
||
ossl_ec_GFp_simple_group_get_degree,
|
||
ossl_ec_group_simple_order_bits,
|
||
ossl_ec_GFp_simple_group_check_discriminant,
|
||
ossl_ec_GFp_simple_point_init,
|
||
ossl_ec_GFp_simple_point_finish,
|
||
ossl_ec_GFp_simple_point_clear_finish,
|
||
ossl_ec_GFp_simple_point_copy,
|
||
ossl_ec_GFp_simple_point_set_to_infinity,
|
||
ossl_ec_GFp_simple_point_set_affine_coordinates,
|
||
ossl_ec_GFp_simple_point_get_affine_coordinates,
|
||
0, 0, 0,
|
||
ossl_ec_GFp_simple_add,
|
||
ossl_ec_GFp_simple_dbl,
|
||
ossl_ec_GFp_simple_invert,
|
||
ossl_ec_GFp_simple_is_at_infinity,
|
||
ossl_ec_GFp_simple_is_on_curve,
|
||
ossl_ec_GFp_simple_cmp,
|
||
ossl_ec_GFp_simple_make_affine,
|
||
ossl_ec_GFp_simple_points_make_affine,
|
||
ecp_sm2p256_points_mul, /* mul */
|
||
0 /* precompute_mult */,
|
||
0 /* have_precompute_mult */,
|
||
ecp_sm2p256_field_mul,
|
||
ecp_sm2p256_field_sqr,
|
||
0 /* field_div */,
|
||
ossl_ec_GFp_simple_field_inv,
|
||
0 /* field_encode */,
|
||
0 /* field_decode */,
|
||
0 /* field_set_to_one */,
|
||
ossl_ec_key_simple_priv2oct,
|
||
ossl_ec_key_simple_oct2priv,
|
||
0, /* set private */
|
||
ossl_ec_key_simple_generate_key,
|
||
ossl_ec_key_simple_check_key,
|
||
ossl_ec_key_simple_generate_public_key,
|
||
0, /* keycopy */
|
||
0, /* keyfinish */
|
||
ossl_ecdh_simple_compute_key,
|
||
ossl_ecdsa_simple_sign_setup,
|
||
ossl_ecdsa_simple_sign_sig,
|
||
ossl_ecdsa_simple_verify_sig,
|
||
0, /* use constant‑time fallback for inverse mod order */
|
||
0, /* blind_coordinates */
|
||
0, /* ladder_pre */
|
||
0, /* ladder_step */
|
||
0 /* ladder_post */
|
||
};
|
||
|
||
return &ret;
|
||
}
|