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1 files changed, 305 insertions, 0 deletions
diff --git a/security/nss/lib/freebl/ecl/ecl_mult.c b/security/nss/lib/freebl/ecl/ecl_mult.c
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+++ b/security/nss/lib/freebl/ecl/ecl_mult.c
@@ -0,0 +1,305 @@
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+#include "mpi.h"
+#include "mplogic.h"
+#include "ecl.h"
+#include "ecl-priv.h"
+#include <stdlib.h>
+
+/* Elliptic curve scalar-point multiplication. Computes R(x, y) = k * P(x,
+ * y). If x, y = NULL, then P is assumed to be the generator (base point)
+ * of the group of points on the elliptic curve. Input and output values
+ * are assumed to be NOT field-encoded. */
+mp_err
+ECPoint_mul(const ECGroup *group, const mp_int *k, const mp_int *px,
+ const mp_int *py, mp_int *rx, mp_int *ry)
+{
+ mp_err res = MP_OKAY;
+ mp_int kt;
+
+ ARGCHK((k != NULL) && (group != NULL), MP_BADARG);
+ MP_DIGITS(&kt) = 0;
+
+ /* want scalar to be less than or equal to group order */
+ if (mp_cmp(k, &group->order) > 0) {
+ MP_CHECKOK(mp_init(&kt));
+ MP_CHECKOK(mp_mod(k, &group->order, &kt));
+ } else {
+ MP_SIGN(&kt) = MP_ZPOS;
+ MP_USED(&kt) = MP_USED(k);
+ MP_ALLOC(&kt) = MP_ALLOC(k);
+ MP_DIGITS(&kt) = MP_DIGITS(k);
+ }
+
+ if ((px == NULL) || (py == NULL)) {
+ if (group->base_point_mul) {
+ MP_CHECKOK(group->base_point_mul(&kt, rx, ry, group));
+ } else {
+ MP_CHECKOK(group->point_mul(&kt, &group->genx, &group->geny, rx, ry,
+ group));
+ }
+ } else {
+ if (group->meth->field_enc) {
+ MP_CHECKOK(group->meth->field_enc(px, rx, group->meth));
+ MP_CHECKOK(group->meth->field_enc(py, ry, group->meth));
+ MP_CHECKOK(group->point_mul(&kt, rx, ry, rx, ry, group));
+ } else {
+ MP_CHECKOK(group->point_mul(&kt, px, py, rx, ry, group));
+ }
+ }
+ if (group->meth->field_dec) {
+ MP_CHECKOK(group->meth->field_dec(rx, rx, group->meth));
+ MP_CHECKOK(group->meth->field_dec(ry, ry, group->meth));
+ }
+
+CLEANUP:
+ if (MP_DIGITS(&kt) != MP_DIGITS(k)) {
+ mp_clear(&kt);
+ }
+ return res;
+}
+
+/* Elliptic curve scalar-point multiplication. Computes R(x, y) = k1 * G +
+ * k2 * P(x, y), where G is the generator (base point) of the group of
+ * points on the elliptic curve. Allows k1 = NULL or { k2, P } = NULL.
+ * Input and output values are assumed to be NOT field-encoded. */
+mp_err
+ec_pts_mul_basic(const mp_int *k1, const mp_int *k2, const mp_int *px,
+ const mp_int *py, mp_int *rx, mp_int *ry,
+ const ECGroup *group)
+{
+ mp_err res = MP_OKAY;
+ mp_int sx, sy;
+
+ ARGCHK(group != NULL, MP_BADARG);
+ ARGCHK(!((k1 == NULL) && ((k2 == NULL) || (px == NULL) || (py == NULL))), MP_BADARG);
+
+ /* if some arguments are not defined used ECPoint_mul */
+ if (k1 == NULL) {
+ return ECPoint_mul(group, k2, px, py, rx, ry);
+ } else if ((k2 == NULL) || (px == NULL) || (py == NULL)) {
+ return ECPoint_mul(group, k1, NULL, NULL, rx, ry);
+ }
+
+ MP_DIGITS(&sx) = 0;
+ MP_DIGITS(&sy) = 0;
+ MP_CHECKOK(mp_init(&sx));
+ MP_CHECKOK(mp_init(&sy));
+
+ MP_CHECKOK(ECPoint_mul(group, k1, NULL, NULL, &sx, &sy));
+ MP_CHECKOK(ECPoint_mul(group, k2, px, py, rx, ry));
+
+ if (group->meth->field_enc) {
+ MP_CHECKOK(group->meth->field_enc(&sx, &sx, group->meth));
+ MP_CHECKOK(group->meth->field_enc(&sy, &sy, group->meth));
+ MP_CHECKOK(group->meth->field_enc(rx, rx, group->meth));
+ MP_CHECKOK(group->meth->field_enc(ry, ry, group->meth));
+ }
+
+ MP_CHECKOK(group->point_add(&sx, &sy, rx, ry, rx, ry, group));
+
+ if (group->meth->field_dec) {
+ MP_CHECKOK(group->meth->field_dec(rx, rx, group->meth));
+ MP_CHECKOK(group->meth->field_dec(ry, ry, group->meth));
+ }
+
+CLEANUP:
+ mp_clear(&sx);
+ mp_clear(&sy);
+ return res;
+}
+
+/* Elliptic curve scalar-point multiplication. Computes R(x, y) = k1 * G +
+ * k2 * P(x, y), where G is the generator (base point) of the group of
+ * points on the elliptic curve. Allows k1 = NULL or { k2, P } = NULL.
+ * Input and output values are assumed to be NOT field-encoded. Uses
+ * algorithm 15 (simultaneous multiple point multiplication) from Brown,
+ * Hankerson, Lopez, Menezes. Software Implementation of the NIST
+ * Elliptic Curves over Prime Fields. */
+mp_err
+ec_pts_mul_simul_w2(const mp_int *k1, const mp_int *k2, const mp_int *px,
+ const mp_int *py, mp_int *rx, mp_int *ry,
+ const ECGroup *group)
+{
+ mp_err res = MP_OKAY;
+ mp_int precomp[4][4][2];
+ const mp_int *a, *b;
+ unsigned int i, j;
+ int ai, bi, d;
+
+ ARGCHK(group != NULL, MP_BADARG);
+ ARGCHK(!((k1 == NULL) && ((k2 == NULL) || (px == NULL) || (py == NULL))), MP_BADARG);
+
+ /* if some arguments are not defined used ECPoint_mul */
+ if (k1 == NULL) {
+ return ECPoint_mul(group, k2, px, py, rx, ry);
+ } else if ((k2 == NULL) || (px == NULL) || (py == NULL)) {
+ return ECPoint_mul(group, k1, NULL, NULL, rx, ry);
+ }
+
+ /* initialize precomputation table */
+ for (i = 0; i < 4; i++) {
+ for (j = 0; j < 4; j++) {
+ MP_DIGITS(&precomp[i][j][0]) = 0;
+ MP_DIGITS(&precomp[i][j][1]) = 0;
+ }
+ }
+ for (i = 0; i < 4; i++) {
+ for (j = 0; j < 4; j++) {
+ MP_CHECKOK(mp_init_size(&precomp[i][j][0],
+ ECL_MAX_FIELD_SIZE_DIGITS));
+ MP_CHECKOK(mp_init_size(&precomp[i][j][1],
+ ECL_MAX_FIELD_SIZE_DIGITS));
+ }
+ }
+
+ /* fill precomputation table */
+ /* assign {k1, k2} = {a, b} such that len(a) >= len(b) */
+ if (mpl_significant_bits(k1) < mpl_significant_bits(k2)) {
+ a = k2;
+ b = k1;
+ if (group->meth->field_enc) {
+ MP_CHECKOK(group->meth->field_enc(px, &precomp[1][0][0], group->meth));
+ MP_CHECKOK(group->meth->field_enc(py, &precomp[1][0][1], group->meth));
+ } else {
+ MP_CHECKOK(mp_copy(px, &precomp[1][0][0]));
+ MP_CHECKOK(mp_copy(py, &precomp[1][0][1]));
+ }
+ MP_CHECKOK(mp_copy(&group->genx, &precomp[0][1][0]));
+ MP_CHECKOK(mp_copy(&group->geny, &precomp[0][1][1]));
+ } else {
+ a = k1;
+ b = k2;
+ MP_CHECKOK(mp_copy(&group->genx, &precomp[1][0][0]));
+ MP_CHECKOK(mp_copy(&group->geny, &precomp[1][0][1]));
+ if (group->meth->field_enc) {
+ MP_CHECKOK(group->meth->field_enc(px, &precomp[0][1][0], group->meth));
+ MP_CHECKOK(group->meth->field_enc(py, &precomp[0][1][1], group->meth));
+ } else {
+ MP_CHECKOK(mp_copy(px, &precomp[0][1][0]));
+ MP_CHECKOK(mp_copy(py, &precomp[0][1][1]));
+ }
+ }
+ /* precompute [*][0][*] */
+ mp_zero(&precomp[0][0][0]);
+ mp_zero(&precomp[0][0][1]);
+ MP_CHECKOK(group->point_dbl(&precomp[1][0][0], &precomp[1][0][1],
+ &precomp[2][0][0], &precomp[2][0][1], group));
+ MP_CHECKOK(group->point_add(&precomp[1][0][0], &precomp[1][0][1],
+ &precomp[2][0][0], &precomp[2][0][1],
+ &precomp[3][0][0], &precomp[3][0][1], group));
+ /* precompute [*][1][*] */
+ for (i = 1; i < 4; i++) {
+ MP_CHECKOK(group->point_add(&precomp[0][1][0], &precomp[0][1][1],
+ &precomp[i][0][0], &precomp[i][0][1],
+ &precomp[i][1][0], &precomp[i][1][1], group));
+ }
+ /* precompute [*][2][*] */
+ MP_CHECKOK(group->point_dbl(&precomp[0][1][0], &precomp[0][1][1],
+ &precomp[0][2][0], &precomp[0][2][1], group));
+ for (i = 1; i < 4; i++) {
+ MP_CHECKOK(group->point_add(&precomp[0][2][0], &precomp[0][2][1],
+ &precomp[i][0][0], &precomp[i][0][1],
+ &precomp[i][2][0], &precomp[i][2][1], group));
+ }
+ /* precompute [*][3][*] */
+ MP_CHECKOK(group->point_add(&precomp[0][1][0], &precomp[0][1][1],
+ &precomp[0][2][0], &precomp[0][2][1],
+ &precomp[0][3][0], &precomp[0][3][1], group));
+ for (i = 1; i < 4; i++) {
+ MP_CHECKOK(group->point_add(&precomp[0][3][0], &precomp[0][3][1],
+ &precomp[i][0][0], &precomp[i][0][1],
+ &precomp[i][3][0], &precomp[i][3][1], group));
+ }
+
+ d = (mpl_significant_bits(a) + 1) / 2;
+
+ /* R = inf */
+ mp_zero(rx);
+ mp_zero(ry);
+
+ for (i = d; i-- > 0;) {
+ ai = MP_GET_BIT(a, 2 * i + 1);
+ ai <<= 1;
+ ai |= MP_GET_BIT(a, 2 * i);
+ bi = MP_GET_BIT(b, 2 * i + 1);
+ bi <<= 1;
+ bi |= MP_GET_BIT(b, 2 * i);
+ /* R = 2^2 * R */
+ MP_CHECKOK(group->point_dbl(rx, ry, rx, ry, group));
+ MP_CHECKOK(group->point_dbl(rx, ry, rx, ry, group));
+ /* R = R + (ai * A + bi * B) */
+ MP_CHECKOK(group->point_add(rx, ry, &precomp[ai][bi][0],
+ &precomp[ai][bi][1], rx, ry, group));
+ }
+
+ if (group->meth->field_dec) {
+ MP_CHECKOK(group->meth->field_dec(rx, rx, group->meth));
+ MP_CHECKOK(group->meth->field_dec(ry, ry, group->meth));
+ }
+
+CLEANUP:
+ for (i = 0; i < 4; i++) {
+ for (j = 0; j < 4; j++) {
+ mp_clear(&precomp[i][j][0]);
+ mp_clear(&precomp[i][j][1]);
+ }
+ }
+ return res;
+}
+
+/* Elliptic curve scalar-point multiplication. Computes R(x, y) = k1 * G +
+ * k2 * P(x, y), where G is the generator (base point) of the group of
+ * points on the elliptic curve. Allows k1 = NULL or { k2, P } = NULL.
+ * Input and output values are assumed to be NOT field-encoded. */
+mp_err
+ECPoints_mul(const ECGroup *group, const mp_int *k1, const mp_int *k2,
+ const mp_int *px, const mp_int *py, mp_int *rx, mp_int *ry)
+{
+ mp_err res = MP_OKAY;
+ mp_int k1t, k2t;
+ const mp_int *k1p, *k2p;
+
+ MP_DIGITS(&k1t) = 0;
+ MP_DIGITS(&k2t) = 0;
+
+ ARGCHK(group != NULL, MP_BADARG);
+
+ /* want scalar to be less than or equal to group order */
+ if (k1 != NULL) {
+ if (mp_cmp(k1, &group->order) >= 0) {
+ MP_CHECKOK(mp_init(&k1t));
+ MP_CHECKOK(mp_mod(k1, &group->order, &k1t));
+ k1p = &k1t;
+ } else {
+ k1p = k1;
+ }
+ } else {
+ k1p = k1;
+ }
+ if (k2 != NULL) {
+ if (mp_cmp(k2, &group->order) >= 0) {
+ MP_CHECKOK(mp_init(&k2t));
+ MP_CHECKOK(mp_mod(k2, &group->order, &k2t));
+ k2p = &k2t;
+ } else {
+ k2p = k2;
+ }
+ } else {
+ k2p = k2;
+ }
+
+ /* if points_mul is defined, then use it */
+ if (group->points_mul) {
+ res = group->points_mul(k1p, k2p, px, py, rx, ry, group);
+ } else {
+ res = ec_pts_mul_simul_w2(k1p, k2p, px, py, rx, ry, group);
+ }
+
+CLEANUP:
+ mp_clear(&k1t);
+ mp_clear(&k2t);
+ return res;
+}
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