diff options
author | Andy Polyakov <appro@openssl.org> | 2015-01-21 17:28:45 +0100 |
---|---|---|
committer | Matt Caswell <matt@openssl.org> | 2015-01-22 09:28:26 +0000 |
commit | 319d5c7a586a5695589494e16cb3dd5f82d753ca (patch) | |
tree | 4f7495a0e7d8029d63083db12aee8f43432b7a75 /crypto/ec | |
parent | 3807db9d91d07fd11432325cdf3c51a0c901f0b6 (diff) |
ec/ecp_nistz256.c: further harmonization with latest rules.
Conflicts:
crypto/ec/ecp_nistz256.c
Reviewed-by: Tim Hudson <tjh@openssl.org>
Diffstat (limited to 'crypto/ec')
-rw-r--r-- | crypto/ec/ecp_nistz256.c | 100 |
1 files changed, 63 insertions, 37 deletions
diff --git a/crypto/ec/ecp_nistz256.c b/crypto/ec/ecp_nistz256.c index d8c0dae1ae..2cd6599d85 100644 --- a/crypto/ec/ecp_nistz256.c +++ b/crypto/ec/ecp_nistz256.c @@ -71,9 +71,11 @@ typedef P256_POINT_AFFINE PRECOMP256_ROW[64]; 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; @@ -89,15 +91,15 @@ void ecp_nistz256_div_by_2(BN_ULONG res[P256_LIMBS], /* 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], @@ -275,8 +277,8 @@ static void ecp_nistz256_point_double(P256_POINT *r, const P256_POINT *a) } /* 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]; @@ -332,8 +334,9 @@ static void ecp_nistz256_point_add(P256_POINT * r, 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); @@ -400,8 +403,10 @@ static void ecp_nistz256_point_add_affine(P256_POINT *r, 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) @@ -463,8 +468,10 @@ static void ecp_nistz256_point_add_affine(P256_POINT *r, 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]; @@ -534,10 +541,12 @@ static void ecp_nistz256_mod_inverse(BN_ULONG r[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) { if (in->top > P256_LIMBS) return 0; @@ -563,7 +572,7 @@ static void ecp_nistz256_windowed_mul(const EC_GROUP *group, BN_ULONG tmp[P256_LIMBS]; ALIGN32 P256_POINT h; const BIGNUM **scalars = NULL; - P256_POINT(*table)[16] = NULL; + P256_POINT (*table)[16] = NULL; void *table_storage = NULL; if ((table_storage = @@ -708,8 +717,10 @@ const static BN_ULONG def_yG[P256_LIMBS] = { 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 (generator->X.top == P256_LIMBS) && @@ -721,10 +732,12 @@ static int ecp_nistz256_is_affine_G(const EC_POINT *generator) 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; @@ -747,8 +760,10 @@ static int ecp_nistz256_mult_precompute(EC_GROUP *group, BN_CTX *ctx) } 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; } @@ -788,16 +803,20 @@ static int ecp_nistz256_mult_precompute(EC_GROUP *group, BN_CTX *ctx) 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++) { - /* It would be faster to use + /* + * It would be faster to use * ec_GFp_simple_points_make_affine and make multiple - * points affine at the same time. */ + * points affine at the same time. + */ ec_GFp_simple_make_affine(group, P, ctx); ecp_nistz256_bignum_to_field_elem(preComputedTable[j] [k].X, &P->X); @@ -886,9 +905,11 @@ static void booth_recode_w7(unsigned char *sign, *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]) @@ -1126,9 +1147,10 @@ static int ecp_nistz256_points_mul(const EC_GROUP *group, 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; @@ -1144,10 +1166,12 @@ static int ecp_nistz256_points_mul(const EC_GROUP *group, } if (preComputedTable == NULL && ecp_nistz256_is_affine_G(generator)) { - /* If there is no precomputed data, but the 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. */ + * Apache, do not use EC_KEY_precompute_mult. + */ preComputedTable = (const PRECOMP256_ROW *)ecp_nistz256_precomputed; } @@ -1227,8 +1251,10 @@ static int ecp_nistz256_points_mul(const EC_GROUP *group, 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; |