typedef struct ec_pre_comp_st {
const EC_GROUP *group; /* Parent EC_GROUP object */
size_t w; /* Window size */
- /* Constant time access to the X and Y coordinates of the pre-computed,
+ /*
+ * Constant time access to the X and Y coordinates of the pre-computed,
* generator multiplies, in the Montgomery domain. Pre-calculated
- * multiplies are stored in affine form. */
+ * multiplies are stored in affine form.
+ */
PRECOMP256_ROW *precomp;
void *precomp_storage;
int references;
/* Modular mul by 3: res = 3*a mod P */
void ecp_nistz256_mul_by_3(BN_ULONG res[P256_LIMBS],
const BN_ULONG a[P256_LIMBS]);
-/* Modular add: res = a+b mod P */
+/* Modular add: res = a+b mod P */
void ecp_nistz256_add(BN_ULONG res[P256_LIMBS],
const BN_ULONG a[P256_LIMBS],
const BN_ULONG b[P256_LIMBS]);
-/* Modular sub: res = a-b mod P */
+/* Modular sub: res = a-b mod P */
void ecp_nistz256_sub(BN_ULONG res[P256_LIMBS],
const BN_ULONG a[P256_LIMBS],
const BN_ULONG b[P256_LIMBS]);
-/* Modular neg: res = -a mod P */
+/* Modular neg: res = -a mod P */
void ecp_nistz256_neg(BN_ULONG res[P256_LIMBS], const BN_ULONG a[P256_LIMBS]);
/* Montgomery mul: res = a*b*2^-256 mod P */
void ecp_nistz256_mul_mont(BN_ULONG res[P256_LIMBS],
const BN_ULONG in[P256_LIMBS]);
/* Functions that perform constant time access to the precomputed tables */
void ecp_nistz256_scatter_w5(P256_POINT *val,
- const P256_POINT *in_t, int index);
-void ecp_nistz256_gather_w5(P256_POINT * val,
+ const P256_POINT *in_t, int index);
+void ecp_nistz256_gather_w5(P256_POINT *val,
const P256_POINT *in_t, int index);
void ecp_nistz256_scatter_w7(P256_POINT_AFFINE *val,
- const P256_POINT_AFFINE *in_t, int index);
+ const P256_POINT_AFFINE *in_t, int index);
void ecp_nistz256_gather_w7(P256_POINT_AFFINE *val,
const P256_POINT_AFFINE *in_t, int index);
}
/* Point addition: r = a+b */
-static void ecp_nistz256_point_add(P256_POINT * r,
- const P256_POINT * a, const P256_POINT * b)
+static void ecp_nistz256_point_add(P256_POINT *r,
+ const P256_POINT *a, const P256_POINT *b)
{
BN_ULONG U2[P256_LIMBS], S2[P256_LIMBS];
BN_ULONG U1[P256_LIMBS], S1[P256_LIMBS];
ecp_nistz256_mul_mont(U2, in2_x, Z1sqr); /* U2 = X2*Z1^2 */
ecp_nistz256_sub(H, U2, U1); /* H = U2 - U1 */
- /* This should not happen during sign/ecdh,
- * so no constant time violation */
+ /*
+ * This should not happen during sign/ecdh, so no constant time violation
+ */
if (is_equal(U1, U2) && !in1infty && !in2infty) {
if (is_equal(S1, S2)) {
ecp_nistz256_point_double(r, a);
const BN_ULONG *in2_x = b->X;
const BN_ULONG *in2_y = b->Y;
- /* In affine representation we encode infty as (0,0),
- * which is not on the curve, so it is OK */
+ /*
+ * In affine representation we encode infty as (0,0), which is not on the
+ * curve, so it is OK
+ */
in1infty = (in1_x[0] | in1_x[1] | in1_x[2] | in1_x[3] |
in1_y[0] | in1_y[1] | in1_y[2] | in1_y[3]);
if (P256_LIMBS == 8)
static void ecp_nistz256_mod_inverse(BN_ULONG r[P256_LIMBS],
const BN_ULONG in[P256_LIMBS])
{
- /* The poly is ffffffff 00000001 00000000 00000000 00000000 ffffffff ffffffff ffffffff
- We use FLT and used poly-2 as exponent */
+ /*
+ * The poly is ffffffff 00000001 00000000 00000000 00000000 ffffffff
+ * ffffffff ffffffff We use FLT and used poly-2 as exponent
+ */
BN_ULONG p2[P256_LIMBS];
BN_ULONG p4[P256_LIMBS];
BN_ULONG p8[P256_LIMBS];
memcpy(r, res, sizeof(res));
}
-/* ecp_nistz256_bignum_to_field_elem copies the contents of |in| to |out| and
- * returns one if it fits. Otherwise it returns zero. */
+/*
+ * ecp_nistz256_bignum_to_field_elem copies the contents of |in| to |out| and
+ * returns one if it fits. Otherwise it returns zero.
+ */
static int ecp_nistz256_bignum_to_field_elem(BN_ULONG out[P256_LIMBS],
- const BIGNUM * in)
+ const BIGNUM *in)
{
return bn_copy_words(out, in, P256_LIMBS);
}
const unsigned int window_size = 5;
const unsigned int mask = (1 << (window_size + 1)) - 1;
unsigned int wvalue;
- P256_POINT *temp; /* place for 5 temporary points */
+ P256_POINT *temp; /* place for 5 temporary points */
const BIGNUM **scalars = NULL;
- P256_POINT(*table)[16] = NULL;
+ P256_POINT (*table)[16] = NULL;
void *table_storage = NULL;
if ((table_storage =
}
table = (void *)ALIGNPTR(table_storage, 64);
- temp = (P256_POINT *)(table + num);
+ temp = (P256_POINT *)(table + num);
for (i = 0; i < num; i++) {
P256_POINT *row = table[i];
goto err;
}
- /* row[0] is implicitly (0,0,0) (the point at infinity),
- * therefore it is not stored. All other values are actually
- * stored with an offset of -1 in table.
+ /*
+ * row[0] is implicitly (0,0,0) (the point at infinity), therefore it
+ * is not stored. All other values are actually stored with an offset
+ * of -1 in table.
*/
ecp_nistz256_scatter_w5 (row, &temp[0], 1);
TOBN(0xd2e88688, 0xdd21f325), TOBN(0x8571ff18, 0x25885d85)
};
-/* ecp_nistz256_is_affine_G returns one if |generator| is the standard,
- * P-256 generator. */
+/*
+ * ecp_nistz256_is_affine_G returns one if |generator| is the standard, P-256
+ * generator.
+ */
static int ecp_nistz256_is_affine_G(const EC_POINT *generator)
{
return (bn_get_top(generator->X) == P256_LIMBS) &&
static int ecp_nistz256_mult_precompute(EC_GROUP *group, BN_CTX *ctx)
{
- /* We precompute a table for a Booth encoded exponent (wNAF) based
+ /*
+ * We precompute a table for a Booth encoded exponent (wNAF) based
* computation. Each table holds 64 values for safe access, with an
- * implicit value of infinity at index zero. We use window of size 7,
- * and therefore require ceil(256/7) = 37 tables. */
+ * implicit value of infinity at index zero. We use window of size 7, and
+ * therefore require ceil(256/7) = 37 tables.
+ */
BIGNUM *order;
EC_POINT *P = NULL, *T = NULL;
const EC_POINT *generator;
}
if (ecp_nistz256_is_affine_G(generator)) {
- /* No need to calculate tables for the standard generator
- * because we have them statically. */
+ /*
+ * No need to calculate tables for the standard generator because we
+ * have them statically.
+ */
return 1;
}
P = EC_POINT_new(group);
T = EC_POINT_new(group);
- /* The zero entry is implicitly infinity, and we skip it,
- * storing other values with -1 offset. */
+ /*
+ * The zero entry is implicitly infinity, and we skip it, storing other
+ * values with -1 offset.
+ */
EC_POINT_copy(T, generator);
for (k = 0; k < 64; k++) {
EC_POINT_copy(P, T);
for (j = 0; j < 37; j++) {
P256_POINT_AFFINE temp;
- /* It would be faster to use
- * ec_GFp_simple_points_make_affine and make multiple
- * points affine at the same time. */
+ /*
+ * It would be faster to use ec_GFp_simple_points_make_affine and
+ * make multiple points affine at the same time.
+ */
ec_GFp_simple_make_affine(group, P, ctx);
ecp_nistz256_bignum_to_field_elem(temp.X, P->X);
ecp_nistz256_bignum_to_field_elem(temp.Y, P->Y);
*digit = d;
}
-/* ecp_nistz256_avx2_mul_g performs multiplication by G, using only the
+/*
+ * ecp_nistz256_avx2_mul_g performs multiplication by G, using only the
* precomputed table. It does 4 affine point additions in parallel,
- * significantly speeding up point multiplication for a fixed value. */
+ * significantly speeding up point multiplication for a fixed value.
+ */
static void ecp_nistz256_avx2_mul_g(P256_POINT *r,
unsigned char p_str[33],
const P256_POINT_AFFINE(*preComputedTable)[64])
ecp_nistz256_pre_comp_clear_free);
if (pre_comp) {
- /* If there is a precomputed table for the generator,
- * check that it was generated with the same
- * generator. */
+ /*
+ * If there is a precomputed table for the generator, check that
+ * it was generated with the same generator.
+ */
EC_POINT *pre_comp_generator = EC_POINT_new(group);
if (pre_comp_generator == NULL)
goto err;
}
if (preComputedTable == NULL && ecp_nistz256_is_affine_G(generator)) {
- /* If there is no precomputed data, but the generator
- * is the default, a hardcoded table of precomputed
- * data is used. This is because applications, such as
- * Apache, do not use EC_KEY_precompute_mult. */
+ /*
+ * If there is no precomputed data, but the generator is the
+ * default, a hardcoded table of precomputed data is used. This
+ * is because applications, such as Apache, do not use
+ * EC_KEY_precompute_mult.
+ */
preComputedTable = ecp_nistz256_precomputed;
}
p_is_infinity = 1;
if (no_precomp_for_generator) {
- /* Without a precomputed table for the generator, it has to be
- * handled like a normal point. */
+ /*
+ * Without a precomputed table for the generator, it has to be
+ * handled like a normal point.
+ */
const BIGNUM **new_scalars;
const EC_POINT **new_points;