jdk/src/share/native/sun/security/ec/ec2_aff.c
changeset 3492 e549cea58864
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/jdk/src/share/native/sun/security/ec/ec2_aff.c	Tue Aug 11 16:52:26 2009 +0100
@@ -0,0 +1,368 @@
+/* *********************************************************************
+ *
+ * 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):
+ *   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
+
+/* Checks if point P(px, py) is at infinity.  Uses affine coordinates. */
+mp_err
+ec_GF2m_pt_is_inf_aff(const mp_int *px, const mp_int *py)
+{
+
+        if ((mp_cmp_z(px) == 0) && (mp_cmp_z(py) == 0)) {
+                return MP_YES;
+        } else {
+                return MP_NO;
+        }
+
+}
+
+/* Sets P(px, py) to be the point at infinity.  Uses affine coordinates. */
+mp_err
+ec_GF2m_pt_set_inf_aff(mp_int *px, mp_int *py)
+{
+        mp_zero(px);
+        mp_zero(py);
+        return MP_OKAY;
+}
+
+/* Computes R = P + Q based on IEEE P1363 A.10.2. Elliptic curve points P,
+ * Q, and R can all be identical. Uses affine coordinates. */
+mp_err
+ec_GF2m_pt_add_aff(const mp_int *px, const mp_int *py, const mp_int *qx,
+                                   const mp_int *qy, mp_int *rx, mp_int *ry,
+                                   const ECGroup *group)
+{
+        mp_err res = MP_OKAY;
+        mp_int lambda, tempx, tempy;
+
+        MP_DIGITS(&lambda) = 0;
+        MP_DIGITS(&tempx) = 0;
+        MP_DIGITS(&tempy) = 0;
+        MP_CHECKOK(mp_init(&lambda, FLAG(px)));
+        MP_CHECKOK(mp_init(&tempx, FLAG(px)));
+        MP_CHECKOK(mp_init(&tempy, FLAG(px)));
+        /* if P = inf, then R = Q */
+        if (ec_GF2m_pt_is_inf_aff(px, py) == 0) {
+                MP_CHECKOK(mp_copy(qx, rx));
+                MP_CHECKOK(mp_copy(qy, ry));
+                res = MP_OKAY;
+                goto CLEANUP;
+        }
+        /* if Q = inf, then R = P */
+        if (ec_GF2m_pt_is_inf_aff(qx, qy) == 0) {
+                MP_CHECKOK(mp_copy(px, rx));
+                MP_CHECKOK(mp_copy(py, ry));
+                res = MP_OKAY;
+                goto CLEANUP;
+        }
+        /* if px != qx, then lambda = (py+qy) / (px+qx), tempx = a + lambda^2
+         * + lambda + px + qx */
+        if (mp_cmp(px, qx) != 0) {
+                MP_CHECKOK(group->meth->field_add(py, qy, &tempy, group->meth));
+                MP_CHECKOK(group->meth->field_add(px, qx, &tempx, group->meth));
+                MP_CHECKOK(group->meth->
+                                   field_div(&tempy, &tempx, &lambda, group->meth));
+                MP_CHECKOK(group->meth->field_sqr(&lambda, &tempx, group->meth));
+                MP_CHECKOK(group->meth->
+                                   field_add(&tempx, &lambda, &tempx, group->meth));
+                MP_CHECKOK(group->meth->
+                                   field_add(&tempx, &group->curvea, &tempx, group->meth));
+                MP_CHECKOK(group->meth->
+                                   field_add(&tempx, px, &tempx, group->meth));
+                MP_CHECKOK(group->meth->
+                                   field_add(&tempx, qx, &tempx, group->meth));
+        } else {
+                /* if py != qy or qx = 0, then R = inf */
+                if (((mp_cmp(py, qy) != 0)) || (mp_cmp_z(qx) == 0)) {
+                        mp_zero(rx);
+                        mp_zero(ry);
+                        res = MP_OKAY;
+                        goto CLEANUP;
+                }
+                /* lambda = qx + qy / qx */
+                MP_CHECKOK(group->meth->field_div(qy, qx, &lambda, group->meth));
+                MP_CHECKOK(group->meth->
+                                   field_add(&lambda, qx, &lambda, group->meth));
+                /* tempx = a + lambda^2 + lambda */
+                MP_CHECKOK(group->meth->field_sqr(&lambda, &tempx, group->meth));
+                MP_CHECKOK(group->meth->
+                                   field_add(&tempx, &lambda, &tempx, group->meth));
+                MP_CHECKOK(group->meth->
+                                   field_add(&tempx, &group->curvea, &tempx, group->meth));
+        }
+        /* ry = (qx + tempx) * lambda + tempx + qy */
+        MP_CHECKOK(group->meth->field_add(qx, &tempx, &tempy, group->meth));
+        MP_CHECKOK(group->meth->
+                           field_mul(&tempy, &lambda, &tempy, group->meth));
+        MP_CHECKOK(group->meth->
+                           field_add(&tempy, &tempx, &tempy, group->meth));
+        MP_CHECKOK(group->meth->field_add(&tempy, qy, ry, group->meth));
+        /* rx = tempx */
+        MP_CHECKOK(mp_copy(&tempx, rx));
+
+  CLEANUP:
+        mp_clear(&lambda);
+        mp_clear(&tempx);
+        mp_clear(&tempy);
+        return res;
+}
+
+/* Computes R = P - Q. Elliptic curve points P, Q, and R can all be
+ * identical. Uses affine coordinates. */
+mp_err
+ec_GF2m_pt_sub_aff(const mp_int *px, const mp_int *py, const mp_int *qx,
+                                   const mp_int *qy, mp_int *rx, mp_int *ry,
+                                   const ECGroup *group)
+{
+        mp_err res = MP_OKAY;
+        mp_int nqy;
+
+        MP_DIGITS(&nqy) = 0;
+        MP_CHECKOK(mp_init(&nqy, FLAG(px)));
+        /* nqy = qx+qy */
+        MP_CHECKOK(group->meth->field_add(qx, qy, &nqy, group->meth));
+        MP_CHECKOK(group->point_add(px, py, qx, &nqy, rx, ry, group));
+  CLEANUP:
+        mp_clear(&nqy);
+        return res;
+}
+
+/* Computes R = 2P. Elliptic curve points P and R can be identical. Uses
+ * affine coordinates. */
+mp_err
+ec_GF2m_pt_dbl_aff(const mp_int *px, const mp_int *py, mp_int *rx,
+                                   mp_int *ry, const ECGroup *group)
+{
+        return group->point_add(px, py, px, py, rx, ry, group);
+}
+
+/* by default, this routine is unused and thus doesn't need to be compiled */
+#ifdef ECL_ENABLE_GF2M_PT_MUL_AFF
+/* Computes R = nP based on IEEE P1363 A.10.3. Elliptic curve points P and
+ * R can be identical. Uses affine coordinates. */
+mp_err
+ec_GF2m_pt_mul_aff(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 k, k3, qx, qy, sx, sy;
+        int b1, b3, i, l;
+
+        MP_DIGITS(&k) = 0;
+        MP_DIGITS(&k3) = 0;
+        MP_DIGITS(&qx) = 0;
+        MP_DIGITS(&qy) = 0;
+        MP_DIGITS(&sx) = 0;
+        MP_DIGITS(&sy) = 0;
+        MP_CHECKOK(mp_init(&k));
+        MP_CHECKOK(mp_init(&k3));
+        MP_CHECKOK(mp_init(&qx));
+        MP_CHECKOK(mp_init(&qy));
+        MP_CHECKOK(mp_init(&sx));
+        MP_CHECKOK(mp_init(&sy));
+
+        /* if n = 0 then r = inf */
+        if (mp_cmp_z(n) == 0) {
+                mp_zero(rx);
+                mp_zero(ry);
+                res = MP_OKAY;
+                goto CLEANUP;
+        }
+        /* Q = P, k = n */
+        MP_CHECKOK(mp_copy(px, &qx));
+        MP_CHECKOK(mp_copy(py, &qy));
+        MP_CHECKOK(mp_copy(n, &k));
+        /* if n < 0 then Q = -Q, k = -k */
+        if (mp_cmp_z(n) < 0) {
+                MP_CHECKOK(group->meth->field_add(&qx, &qy, &qy, group->meth));
+                MP_CHECKOK(mp_neg(&k, &k));
+        }
+#ifdef ECL_DEBUG                                /* basic double and add method */
+        l = mpl_significant_bits(&k) - 1;
+        MP_CHECKOK(mp_copy(&qx, &sx));
+        MP_CHECKOK(mp_copy(&qy, &sy));
+        for (i = l - 1; i >= 0; i--) {
+                /* S = 2S */
+                MP_CHECKOK(group->point_dbl(&sx, &sy, &sx, &sy, group));
+                /* if k_i = 1, then S = S + Q */
+                if (mpl_get_bit(&k, i) != 0) {
+                        MP_CHECKOK(group->
+                                           point_add(&sx, &sy, &qx, &qy, &sx, &sy, group));
+                }
+        }
+#else                                                   /* double and add/subtract method from
+                                                                 * standard */
+        /* k3 = 3 * k */
+        MP_CHECKOK(mp_set_int(&k3, 3));
+        MP_CHECKOK(mp_mul(&k, &k3, &k3));
+        /* S = Q */
+        MP_CHECKOK(mp_copy(&qx, &sx));
+        MP_CHECKOK(mp_copy(&qy, &sy));
+        /* l = index of high order bit in binary representation of 3*k */
+        l = mpl_significant_bits(&k3) - 1;
+        /* for i = l-1 downto 1 */
+        for (i = l - 1; i >= 1; i--) {
+                /* S = 2S */
+                MP_CHECKOK(group->point_dbl(&sx, &sy, &sx, &sy, group));
+                b3 = MP_GET_BIT(&k3, i);
+                b1 = MP_GET_BIT(&k, i);
+                /* if k3_i = 1 and k_i = 0, then S = S + Q */
+                if ((b3 == 1) && (b1 == 0)) {
+                        MP_CHECKOK(group->
+                                           point_add(&sx, &sy, &qx, &qy, &sx, &sy, group));
+                        /* if k3_i = 0 and k_i = 1, then S = S - Q */
+                } else if ((b3 == 0) && (b1 == 1)) {
+                        MP_CHECKOK(group->
+                                           point_sub(&sx, &sy, &qx, &qy, &sx, &sy, group));
+                }
+        }
+#endif
+        /* output S */
+        MP_CHECKOK(mp_copy(&sx, rx));
+        MP_CHECKOK(mp_copy(&sy, ry));
+
+  CLEANUP:
+        mp_clear(&k);
+        mp_clear(&k3);
+        mp_clear(&qx);
+        mp_clear(&qy);
+        mp_clear(&sx);
+        mp_clear(&sy);
+        return res;
+}
+#endif
+
+/* Validates a point on a GF2m curve. */
+mp_err
+ec_GF2m_validate_point(const mp_int *px, const mp_int *py, const ECGroup *group)
+{
+        mp_err res = MP_NO;
+        mp_int accl, accr, tmp, pxt, pyt;
+
+        MP_DIGITS(&accl) = 0;
+        MP_DIGITS(&accr) = 0;
+        MP_DIGITS(&tmp) = 0;
+        MP_DIGITS(&pxt) = 0;
+        MP_DIGITS(&pyt) = 0;
+        MP_CHECKOK(mp_init(&accl, FLAG(px)));
+        MP_CHECKOK(mp_init(&accr, FLAG(px)));
+        MP_CHECKOK(mp_init(&tmp, FLAG(px)));
+        MP_CHECKOK(mp_init(&pxt, FLAG(px)));
+        MP_CHECKOK(mp_init(&pyt, FLAG(px)));
+
+    /* 1: Verify that publicValue is not the point at infinity */
+        if (ec_GF2m_pt_is_inf_aff(px, py) == MP_YES) {
+                res = MP_NO;
+                goto CLEANUP;
+        }
+    /* 2: Verify that the coordinates of publicValue are elements
+     *    of the field.
+     */
+        if ((MP_SIGN(px) == MP_NEG) || (mp_cmp(px, &group->meth->irr) >= 0) ||
+                (MP_SIGN(py) == MP_NEG) || (mp_cmp(py, &group->meth->irr) >= 0)) {
+                res = MP_NO;
+                goto CLEANUP;
+        }
+    /* 3: Verify that publicValue is on the curve. */
+        if (group->meth->field_enc) {
+                group->meth->field_enc(px, &pxt, group->meth);
+                group->meth->field_enc(py, &pyt, group->meth);
+        } else {
+                mp_copy(px, &pxt);
+                mp_copy(py, &pyt);
+        }
+        /* left-hand side: y^2 + x*y  */
+        MP_CHECKOK( group->meth->field_sqr(&pyt, &accl, group->meth) );
+        MP_CHECKOK( group->meth->field_mul(&pxt, &pyt, &tmp, group->meth) );
+        MP_CHECKOK( group->meth->field_add(&accl, &tmp, &accl, group->meth) );
+        /* right-hand side: x^3 + a*x^2 + b */
+        MP_CHECKOK( group->meth->field_sqr(&pxt, &tmp, group->meth) );
+        MP_CHECKOK( group->meth->field_mul(&pxt, &tmp, &accr, group->meth) );
+        MP_CHECKOK( group->meth->field_mul(&group->curvea, &tmp, &tmp, group->meth) );
+        MP_CHECKOK( group->meth->field_add(&tmp, &accr, &accr, group->meth) );
+        MP_CHECKOK( group->meth->field_add(&accr, &group->curveb, &accr, group->meth) );
+        /* check LHS - RHS == 0 */
+        MP_CHECKOK( group->meth->field_add(&accl, &accr, &accr, group->meth) );
+        if (mp_cmp_z(&accr) != 0) {
+                res = MP_NO;
+                goto CLEANUP;
+        }
+    /* 4: Verify that the order of the curve times the publicValue
+     *    is the point at infinity.
+     */
+        MP_CHECKOK( ECPoint_mul(group, &group->order, px, py, &pxt, &pyt) );
+        if (ec_GF2m_pt_is_inf_aff(&pxt, &pyt) != MP_YES) {
+                res = MP_NO;
+                goto CLEANUP;
+        }
+
+        res = MP_YES;
+
+CLEANUP:
+        mp_clear(&accl);
+        mp_clear(&accr);
+        mp_clear(&tmp);
+        mp_clear(&pxt);
+        mp_clear(&pyt);
+        return res;
+}