jdk/src/share/native/sun/security/ec/ecl_mult.c
changeset 3492 e549cea58864
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/jdk/src/share/native/sun/security/ec/ecl_mult.c	Tue Aug 11 16:52:26 2009 +0100
@@ -0,0 +1,378 @@
+/* *********************************************************************
+ *
+ * Sun elects to have this file available under and governed by the
+ * Mozilla Public License Version 1.1 ("MPL") (see
+ * http://www.mozilla.org/MPL/ for full license text). For the avoidance
+ * of doubt and subject to the following, Sun also elects to allow
+ * licensees to use this file under the MPL, the GNU General Public
+ * License version 2 only or the Lesser General Public License version
+ * 2.1 only. Any references to the "GNU General Public License version 2
+ * or later" or "GPL" in the following shall be construed to mean the
+ * GNU General Public License version 2 only. Any references to the "GNU
+ * Lesser General Public License version 2.1 or later" or "LGPL" in the
+ * following shall be construed to mean the GNU Lesser General Public
+ * License version 2.1 only. However, the following notice accompanied
+ * the original version of this file:
+ *
+ * Version: MPL 1.1/GPL 2.0/LGPL 2.1
+ *
+ * The contents of this file are subject to the Mozilla Public License Version
+ * 1.1 (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.mozilla.org/MPL/
+ *
+ * Software distributed under the License is distributed on an "AS IS" basis,
+ * WITHOUT WARRANTY OF ANY KIND, either express or implied. See the License
+ * for the specific language governing rights and limitations under the
+ * License.
+ *
+ * The Original Code is the elliptic curve math library.
+ *
+ * The Initial Developer of the Original Code is
+ * Sun Microsystems, Inc.
+ * Portions created by the Initial Developer are Copyright (C) 2003
+ * the Initial Developer. All Rights Reserved.
+ *
+ * Contributor(s):
+ *   Douglas Stebila <douglas@stebila.ca>, Sun Microsystems Laboratories
+ *
+ * Alternatively, the contents of this file may be used under the terms of
+ * either the GNU General Public License Version 2 or later (the "GPL"), or
+ * the GNU Lesser General Public License Version 2.1 or later (the "LGPL"),
+ * in which case the provisions of the GPL or the LGPL are applicable instead
+ * of those above. If you wish to allow use of your version of this file only
+ * under the terms of either the GPL or the LGPL, and not to allow others to
+ * use your version of this file under the terms of the MPL, indicate your
+ * decision by deleting the provisions above and replace them with the notice
+ * and other provisions required by the GPL or the LGPL. If you do not delete
+ * the provisions above, a recipient may use your version of this file under
+ * the terms of any one of the MPL, the GPL or the LGPL.
+ *
+ *********************************************************************** */
+/*
+ * Copyright 2007 Sun Microsystems, Inc.  All rights reserved.
+ * Use is subject to license terms.
+ */
+
+#pragma ident   "%Z%%M% %I%     %E% SMI"
+
+#include "mpi.h"
+#include "mplogic.h"
+#include "ecl.h"
+#include "ecl-priv.h"
+#ifndef _KERNEL
+#include <stdlib.h>
+#endif
+
+/* 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, FLAG(k)));
+                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, FLAG(k1)));
+        MP_CHECKOK(mp_init(&sy, FLAG(k1)));
+
+        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;
+        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, FLAG(k1)) );
+                         MP_CHECKOK( mp_init_size(&precomp[i][j][1],
+                                         ECL_MAX_FIELD_SIZE_DIGITS, FLAG(k1)) );
+                }
+        }
+
+        /* 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 - 1; i >= 0; i--) {
+                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, FLAG(k1)));
+                        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, FLAG(k2)));
+                        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;
+}