--- /dev/null Thu Jan 01 00:00:00 1970 +0000
+++ b/jdk/src/share/native/sun/security/ec/ec2_mont.c Tue Aug 11 16:52:26 2009 +0100
@@ -0,0 +1,296 @@
+/* *********************************************************************
+ *
+ * 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 for binary polynomial field curves.
+ *
+ * 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):
+ * Sheueling Chang-Shantz <sheueling.chang@sun.com>,
+ * Stephen Fung <fungstep@hotmail.com>, and
+ * 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 "ec2.h"
+#include "mplogic.h"
+#include "mp_gf2m.h"
+#ifndef _KERNEL
+#include <stdlib.h>
+#endif
+
+/* Compute the x-coordinate x/z for the point 2*(x/z) in Montgomery
+ * projective coordinates. Uses algorithm Mdouble in appendix of Lopez, J.
+ * and Dahab, R. "Fast multiplication on elliptic curves over GF(2^m)
+ * without precomputation". modified to not require precomputation of
+ * c=b^{2^{m-1}}. */
+static mp_err
+gf2m_Mdouble(mp_int *x, mp_int *z, const ECGroup *group, int kmflag)
+{
+ mp_err res = MP_OKAY;
+ mp_int t1;
+
+ MP_DIGITS(&t1) = 0;
+ MP_CHECKOK(mp_init(&t1, kmflag));
+
+ MP_CHECKOK(group->meth->field_sqr(x, x, group->meth));
+ MP_CHECKOK(group->meth->field_sqr(z, &t1, group->meth));
+ MP_CHECKOK(group->meth->field_mul(x, &t1, z, group->meth));
+ MP_CHECKOK(group->meth->field_sqr(x, x, group->meth));
+ MP_CHECKOK(group->meth->field_sqr(&t1, &t1, group->meth));
+ MP_CHECKOK(group->meth->
+ field_mul(&group->curveb, &t1, &t1, group->meth));
+ MP_CHECKOK(group->meth->field_add(x, &t1, x, group->meth));
+
+ CLEANUP:
+ mp_clear(&t1);
+ return res;
+}
+
+/* Compute the x-coordinate x1/z1 for the point (x1/z1)+(x2/x2) in
+ * Montgomery projective coordinates. Uses algorithm Madd in appendix of
+ * Lopex, J. and Dahab, R. "Fast multiplication on elliptic curves over
+ * GF(2^m) without precomputation". */
+static mp_err
+gf2m_Madd(const mp_int *x, mp_int *x1, mp_int *z1, mp_int *x2, mp_int *z2,
+ const ECGroup *group, int kmflag)
+{
+ mp_err res = MP_OKAY;
+ mp_int t1, t2;
+
+ MP_DIGITS(&t1) = 0;
+ MP_DIGITS(&t2) = 0;
+ MP_CHECKOK(mp_init(&t1, kmflag));
+ MP_CHECKOK(mp_init(&t2, kmflag));
+
+ MP_CHECKOK(mp_copy(x, &t1));
+ MP_CHECKOK(group->meth->field_mul(x1, z2, x1, group->meth));
+ MP_CHECKOK(group->meth->field_mul(z1, x2, z1, group->meth));
+ MP_CHECKOK(group->meth->field_mul(x1, z1, &t2, group->meth));
+ MP_CHECKOK(group->meth->field_add(z1, x1, z1, group->meth));
+ MP_CHECKOK(group->meth->field_sqr(z1, z1, group->meth));
+ MP_CHECKOK(group->meth->field_mul(z1, &t1, x1, group->meth));
+ MP_CHECKOK(group->meth->field_add(x1, &t2, x1, group->meth));
+
+ CLEANUP:
+ mp_clear(&t1);
+ mp_clear(&t2);
+ return res;
+}
+
+/* Compute the x, y affine coordinates from the point (x1, z1) (x2, z2)
+ * using Montgomery point multiplication algorithm Mxy() in appendix of
+ * Lopex, J. and Dahab, R. "Fast multiplication on elliptic curves over
+ * GF(2^m) without precomputation". Returns: 0 on error 1 if return value
+ * should be the point at infinity 2 otherwise */
+static int
+gf2m_Mxy(const mp_int *x, const mp_int *y, mp_int *x1, mp_int *z1,
+ mp_int *x2, mp_int *z2, const ECGroup *group)
+{
+ mp_err res = MP_OKAY;
+ int ret = 0;
+ mp_int t3, t4, t5;
+
+ MP_DIGITS(&t3) = 0;
+ MP_DIGITS(&t4) = 0;
+ MP_DIGITS(&t5) = 0;
+ MP_CHECKOK(mp_init(&t3, FLAG(x2)));
+ MP_CHECKOK(mp_init(&t4, FLAG(x2)));
+ MP_CHECKOK(mp_init(&t5, FLAG(x2)));
+
+ if (mp_cmp_z(z1) == 0) {
+ mp_zero(x2);
+ mp_zero(z2);
+ ret = 1;
+ goto CLEANUP;
+ }
+
+ if (mp_cmp_z(z2) == 0) {
+ MP_CHECKOK(mp_copy(x, x2));
+ MP_CHECKOK(group->meth->field_add(x, y, z2, group->meth));
+ ret = 2;
+ goto CLEANUP;
+ }
+
+ MP_CHECKOK(mp_set_int(&t5, 1));
+ if (group->meth->field_enc) {
+ MP_CHECKOK(group->meth->field_enc(&t5, &t5, group->meth));
+ }
+
+ MP_CHECKOK(group->meth->field_mul(z1, z2, &t3, group->meth));
+
+ MP_CHECKOK(group->meth->field_mul(z1, x, z1, group->meth));
+ MP_CHECKOK(group->meth->field_add(z1, x1, z1, group->meth));
+ MP_CHECKOK(group->meth->field_mul(z2, x, z2, group->meth));
+ MP_CHECKOK(group->meth->field_mul(z2, x1, x1, group->meth));
+ MP_CHECKOK(group->meth->field_add(z2, x2, z2, group->meth));
+
+ MP_CHECKOK(group->meth->field_mul(z2, z1, z2, group->meth));
+ MP_CHECKOK(group->meth->field_sqr(x, &t4, group->meth));
+ MP_CHECKOK(group->meth->field_add(&t4, y, &t4, group->meth));
+ MP_CHECKOK(group->meth->field_mul(&t4, &t3, &t4, group->meth));
+ MP_CHECKOK(group->meth->field_add(&t4, z2, &t4, group->meth));
+
+ MP_CHECKOK(group->meth->field_mul(&t3, x, &t3, group->meth));
+ MP_CHECKOK(group->meth->field_div(&t5, &t3, &t3, group->meth));
+ MP_CHECKOK(group->meth->field_mul(&t3, &t4, &t4, group->meth));
+ MP_CHECKOK(group->meth->field_mul(x1, &t3, x2, group->meth));
+ MP_CHECKOK(group->meth->field_add(x2, x, z2, group->meth));
+
+ MP_CHECKOK(group->meth->field_mul(z2, &t4, z2, group->meth));
+ MP_CHECKOK(group->meth->field_add(z2, y, z2, group->meth));
+
+ ret = 2;
+
+ CLEANUP:
+ mp_clear(&t3);
+ mp_clear(&t4);
+ mp_clear(&t5);
+ if (res == MP_OKAY) {
+ return ret;
+ } else {
+ return 0;
+ }
+}
+
+/* Computes R = nP based on algorithm 2P of Lopex, J. and Dahab, R. "Fast
+ * multiplication on elliptic curves over GF(2^m) without
+ * precomputation". Elliptic curve points P and R can be identical. Uses
+ * Montgomery projective coordinates. */
+mp_err
+ec_GF2m_pt_mul_mont(const mp_int *n, const mp_int *px, const mp_int *py,
+ mp_int *rx, mp_int *ry, const ECGroup *group)
+{
+ mp_err res = MP_OKAY;
+ mp_int x1, x2, z1, z2;
+ int i, j;
+ mp_digit top_bit, mask;
+
+ MP_DIGITS(&x1) = 0;
+ MP_DIGITS(&x2) = 0;
+ MP_DIGITS(&z1) = 0;
+ MP_DIGITS(&z2) = 0;
+ MP_CHECKOK(mp_init(&x1, FLAG(n)));
+ MP_CHECKOK(mp_init(&x2, FLAG(n)));
+ MP_CHECKOK(mp_init(&z1, FLAG(n)));
+ MP_CHECKOK(mp_init(&z2, FLAG(n)));
+
+ /* if result should be point at infinity */
+ if ((mp_cmp_z(n) == 0) || (ec_GF2m_pt_is_inf_aff(px, py) == MP_YES)) {
+ MP_CHECKOK(ec_GF2m_pt_set_inf_aff(rx, ry));
+ goto CLEANUP;
+ }
+
+ MP_CHECKOK(mp_copy(px, &x1)); /* x1 = px */
+ MP_CHECKOK(mp_set_int(&z1, 1)); /* z1 = 1 */
+ MP_CHECKOK(group->meth->field_sqr(&x1, &z2, group->meth)); /* z2 =
+ * x1^2 =
+ * px^2 */
+ MP_CHECKOK(group->meth->field_sqr(&z2, &x2, group->meth));
+ MP_CHECKOK(group->meth->field_add(&x2, &group->curveb, &x2, group->meth)); /* x2
+ * =
+ * px^4
+ * +
+ * b
+ */
+
+ /* find top-most bit and go one past it */
+ i = MP_USED(n) - 1;
+ j = MP_DIGIT_BIT - 1;
+ top_bit = 1;
+ top_bit <<= MP_DIGIT_BIT - 1;
+ mask = top_bit;
+ while (!(MP_DIGITS(n)[i] & mask)) {
+ mask >>= 1;
+ j--;
+ }
+ mask >>= 1;
+ j--;
+
+ /* if top most bit was at word break, go to next word */
+ if (!mask) {
+ i--;
+ j = MP_DIGIT_BIT - 1;
+ mask = top_bit;
+ }
+
+ for (; i >= 0; i--) {
+ for (; j >= 0; j--) {
+ if (MP_DIGITS(n)[i] & mask) {
+ MP_CHECKOK(gf2m_Madd(px, &x1, &z1, &x2, &z2, group, FLAG(n)));
+ MP_CHECKOK(gf2m_Mdouble(&x2, &z2, group, FLAG(n)));
+ } else {
+ MP_CHECKOK(gf2m_Madd(px, &x2, &z2, &x1, &z1, group, FLAG(n)));
+ MP_CHECKOK(gf2m_Mdouble(&x1, &z1, group, FLAG(n)));
+ }
+ mask >>= 1;
+ }
+ j = MP_DIGIT_BIT - 1;
+ mask = top_bit;
+ }
+
+ /* convert out of "projective" coordinates */
+ i = gf2m_Mxy(px, py, &x1, &z1, &x2, &z2, group);
+ if (i == 0) {
+ res = MP_BADARG;
+ goto CLEANUP;
+ } else if (i == 1) {
+ MP_CHECKOK(ec_GF2m_pt_set_inf_aff(rx, ry));
+ } else {
+ MP_CHECKOK(mp_copy(&x2, rx));
+ MP_CHECKOK(mp_copy(&z2, ry));
+ }
+
+ CLEANUP:
+ mp_clear(&x1);
+ mp_clear(&x2);
+ mp_clear(&z1);
+ mp_clear(&z2);
+ return res;
+}