[thirdparty/openssl.git] / crypto / ec / ec_mult.c

/*
 * Copyright 2001-2016 The OpenSSL Project Authors. All Rights Reserved.
 * Copyright (c) 2002, Oracle and/or its affiliates. All rights reserved
 *
 * Licensed under the OpenSSL license (the "License").  You may not use
 * this file except in compliance with the License.  You can obtain a copy
 * in the file LICENSE in the source distribution or at
 * https://www.openssl.org/source/license.html
 */

#include <string.h>
#include <openssl/err.h>

#include "internal/cryptlib.h"
#include "internal/bn_int.h"
#include "ec_lcl.h"

/*
 * This file implements the wNAF-based interleaving multi-exponentiation method
 * Formerly at:
 *   http://www.informatik.tu-darmstadt.de/TI/Mitarbeiter/moeller.html#multiexp
 * You might now find it here:
 *   http://link.springer.com/chapter/10.1007%2F3-540-45537-X_13
 *   http://www.bmoeller.de/pdf/TI-01-08.multiexp.pdf
 * For multiplication with precomputation, we use wNAF splitting, formerly at:
 *   http://www.informatik.tu-darmstadt.de/TI/Mitarbeiter/moeller.html#fastexp
 */

/* structure for precomputed multiples of the generator */
struct ec_pre_comp_st {
    const EC_GROUP *group;      /* parent EC_GROUP object */
    size_t blocksize;           /* block size for wNAF splitting */
    size_t numblocks;           /* max. number of blocks for which we have
                                 * precomputation */
    size_t w;                   /* window size */
    EC_POINT **points;          /* array with pre-calculated multiples of
                                 * generator: 'num' pointers to EC_POINT
                                 * objects followed by a NULL */
    size_t num;                 /* numblocks * 2^(w-1) */
    CRYPTO_REF_COUNT references;
    CRYPTO_RWLOCK *lock;
};

static EC_PRE_COMP *ec_pre_comp_new(const EC_GROUP *group)
{
    EC_PRE_COMP *ret = NULL;

    if (!group)
        return NULL;

    ret = OPENSSL_zalloc(sizeof(*ret));
    if (ret == NULL) {
        ECerr(EC_F_EC_PRE_COMP_NEW, ERR_R_MALLOC_FAILURE);
        return ret;
    }

    ret->group = group;
    ret->blocksize = 8;         /* default */
    ret->w = 4;                 /* default */
    ret->references = 1;

    ret->lock = CRYPTO_THREAD_lock_new();
    if (ret->lock == NULL) {
        ECerr(EC_F_EC_PRE_COMP_NEW, ERR_R_MALLOC_FAILURE);
        OPENSSL_free(ret);
        return NULL;
    }
    return ret;
}

EC_PRE_COMP *EC_ec_pre_comp_dup(EC_PRE_COMP *pre)
{
    int i;
    if (pre != NULL)
        CRYPTO_UP_REF(&pre->references, &i, pre->lock);
    return pre;
}

void EC_ec_pre_comp_free(EC_PRE_COMP *pre)
{
    int i;

    if (pre == NULL)
        return;

    CRYPTO_DOWN_REF(&pre->references, &i, pre->lock);
    REF_PRINT_COUNT("EC_ec", pre);
    if (i > 0)
        return;
    REF_ASSERT_ISNT(i < 0);

    if (pre->points != NULL) {
        EC_POINT **pts;

        for (pts = pre->points; *pts != NULL; pts++)
            EC_POINT_free(*pts);
        OPENSSL_free(pre->points);
    }
    CRYPTO_THREAD_lock_free(pre->lock);
    OPENSSL_free(pre);
}

/*
 * TODO: table should be optimised for the wNAF-based implementation,
 * sometimes smaller windows will give better performance (thus the
 * boundaries should be increased)
 */
#define EC_window_bits_for_scalar_size(b) \
                ((size_t) \
                 ((b) >= 2000 ? 6 : \
                  (b) >=  800 ? 5 : \
                  (b) >=  300 ? 4 : \
                  (b) >=   70 ? 3 : \
                  (b) >=   20 ? 2 : \
                  1))

/*-
 * Compute
 *      \sum scalars[i]*points[i],
 * also including
 *      scalar*generator
 * in the addition if scalar != NULL
 */
int ec_wNAF_mul(const EC_GROUP *group, EC_POINT *r, const BIGNUM *scalar,
                size_t num, const EC_POINT *points[], const BIGNUM *scalars[],
                BN_CTX *ctx)
{
    BN_CTX *new_ctx = NULL;
    const EC_POINT *generator = NULL;
    EC_POINT *tmp = NULL;
    size_t totalnum;
    size_t blocksize = 0, numblocks = 0; /* for wNAF splitting */
    size_t pre_points_per_block = 0;
    size_t i, j;
    int k;
    int r_is_inverted = 0;
    int r_is_at_infinity = 1;
    size_t *wsize = NULL;       /* individual window sizes */
    signed char **wNAF = NULL;  /* individual wNAFs */
    size_t *wNAF_len = NULL;
    size_t max_len = 0;
    size_t num_val;
    EC_POINT **val = NULL;      /* precomputation */
    EC_POINT **v;
    EC_POINT ***val_sub = NULL; /* pointers to sub-arrays of 'val' or
                                 * 'pre_comp->points' */
    const EC_PRE_COMP *pre_comp = NULL;
    int num_scalar = 0;         /* flag: will be set to 1 if 'scalar' must be
                                 * treated like other scalars, i.e.
                                 * precomputation is not available */
    int ret = 0;

    if (group->meth != r->meth) {
        ECerr(EC_F_EC_WNAF_MUL, EC_R_INCOMPATIBLE_OBJECTS);
        return 0;
    }

    if ((scalar == NULL) && (num == 0)) {
        return EC_POINT_set_to_infinity(group, r);
    }

    for (i = 0; i < num; i++) {
        if (group->meth != points[i]->meth) {
            ECerr(EC_F_EC_WNAF_MUL, EC_R_INCOMPATIBLE_OBJECTS);
            return 0;
        }
    }

    if (ctx == NULL) {
        ctx = new_ctx = BN_CTX_new();
        if (ctx == NULL)
            goto err;
    }

    if (scalar != NULL) {
        generator = EC_GROUP_get0_generator(group);
        if (generator == NULL) {
            ECerr(EC_F_EC_WNAF_MUL, EC_R_UNDEFINED_GENERATOR);
            goto err;
        }

        /* look if we can use precomputed multiples of generator */

        pre_comp = group->pre_comp.ec;
        if (pre_comp && pre_comp->numblocks
            && (EC_POINT_cmp(group, generator, pre_comp->points[0], ctx) ==
                0)) {
            blocksize = pre_comp->blocksize;

            /*
             * determine maximum number of blocks that wNAF splitting may
             * yield (NB: maximum wNAF length is bit length plus one)
             */
            numblocks = (BN_num_bits(scalar) / blocksize) + 1;

            /*
             * we cannot use more blocks than we have precomputation for
             */
            if (numblocks > pre_comp->numblocks)
                numblocks = pre_comp->numblocks;

            pre_points_per_block = (size_t)1 << (pre_comp->w - 1);

            /* check that pre_comp looks sane */
            if (pre_comp->num != (pre_comp->numblocks * pre_points_per_block)) {
                ECerr(EC_F_EC_WNAF_MUL, ERR_R_INTERNAL_ERROR);
                goto err;
            }
        } else {
            /* can't use precomputation */
            pre_comp = NULL;
            numblocks = 1;
            num_scalar = 1;     /* treat 'scalar' like 'num'-th element of
                                 * 'scalars' */
        }
    }

    totalnum = num + numblocks;

    wsize = OPENSSL_malloc(totalnum * sizeof wsize[0]);
    wNAF_len = OPENSSL_malloc(totalnum * sizeof wNAF_len[0]);
    wNAF = OPENSSL_malloc((totalnum + 1) * sizeof wNAF[0]); /* includes space
                                                             * for pivot */
    val_sub = OPENSSL_malloc(totalnum * sizeof val_sub[0]);

    /* Ensure wNAF is initialised in case we end up going to err */
    if (wNAF != NULL)
        wNAF[0] = NULL;         /* preliminary pivot */

    if (wsize == NULL || wNAF_len == NULL || wNAF == NULL || val_sub == NULL) {
        ECerr(EC_F_EC_WNAF_MUL, ERR_R_MALLOC_FAILURE);
        goto err;
    }

    /*
     * num_val will be the total number of temporarily precomputed points
     */
    num_val = 0;

    for (i = 0; i < num + num_scalar; i++) {
        size_t bits;

        bits = i < num ? BN_num_bits(scalars[i]) : BN_num_bits(scalar);
        wsize[i] = EC_window_bits_for_scalar_size(bits);
        num_val += (size_t)1 << (wsize[i] - 1);
        wNAF[i + 1] = NULL;     /* make sure we always have a pivot */
        wNAF[i] =
            bn_compute_wNAF((i < num ? scalars[i] : scalar), wsize[i],
                            &wNAF_len[i]);
        if (wNAF[i] == NULL)
            goto err;
        if (wNAF_len[i] > max_len)
            max_len = wNAF_len[i];
    }

    if (numblocks) {
        /* we go here iff scalar != NULL */

        if (pre_comp == NULL) {
            if (num_scalar != 1) {
                ECerr(EC_F_EC_WNAF_MUL, ERR_R_INTERNAL_ERROR);
                goto err;
            }
            /* we have already generated a wNAF for 'scalar' */
        } else {
            signed char *tmp_wNAF = NULL;
            size_t tmp_len = 0;

            if (num_scalar != 0) {
                ECerr(EC_F_EC_WNAF_MUL, ERR_R_INTERNAL_ERROR);
                goto err;
            }

            /*
             * use the window size for which we have precomputation
             */
            wsize[num] = pre_comp->w;
            tmp_wNAF = bn_compute_wNAF(scalar, wsize[num], &tmp_len);
            if (!tmp_wNAF)
                goto err;

            if (tmp_len <= max_len) {
                /*
                 * One of the other wNAFs is at least as long as the wNAF
                 * belonging to the generator, so wNAF splitting will not buy
                 * us anything.
                 */

                numblocks = 1;
                totalnum = num + 1; /* don't use wNAF splitting */
                wNAF[num] = tmp_wNAF;
                wNAF[num + 1] = NULL;
                wNAF_len[num] = tmp_len;
                /*
                 * pre_comp->points starts with the points that we need here:
                 */
                val_sub[num] = pre_comp->points;
            } else {
                /*
                 * don't include tmp_wNAF directly into wNAF array - use wNAF
                 * splitting and include the blocks
                 */

                signed char *pp;
                EC_POINT **tmp_points;

                if (tmp_len < numblocks * blocksize) {
                    /*
                     * possibly we can do with fewer blocks than estimated
                     */
                    numblocks = (tmp_len + blocksize - 1) / blocksize;
                    if (numblocks > pre_comp->numblocks) {
                        ECerr(EC_F_EC_WNAF_MUL, ERR_R_INTERNAL_ERROR);
                        OPENSSL_free(tmp_wNAF);
                        goto err;
                    }
                    totalnum = num + numblocks;
                }

                /* split wNAF in 'numblocks' parts */
                pp = tmp_wNAF;
                tmp_points = pre_comp->points;

                for (i = num; i < totalnum; i++) {
                    if (i < totalnum - 1) {
                        wNAF_len[i] = blocksize;
                        if (tmp_len < blocksize) {
                            ECerr(EC_F_EC_WNAF_MUL, ERR_R_INTERNAL_ERROR);
                            OPENSSL_free(tmp_wNAF);
                            goto err;
                        }
                        tmp_len -= blocksize;
                    } else
                        /*
                         * last block gets whatever is left (this could be
                         * more or less than 'blocksize'!)
                         */
                        wNAF_len[i] = tmp_len;

                    wNAF[i + 1] = NULL;
                    wNAF[i] = OPENSSL_malloc(wNAF_len[i]);
                    if (wNAF[i] == NULL) {
                        ECerr(EC_F_EC_WNAF_MUL, ERR_R_MALLOC_FAILURE);
                        OPENSSL_free(tmp_wNAF);
                        goto err;
                    }
                    memcpy(wNAF[i], pp, wNAF_len[i]);
                    if (wNAF_len[i] > max_len)
                        max_len = wNAF_len[i];

                    if (*tmp_points == NULL) {
                        ECerr(EC_F_EC_WNAF_MUL, ERR_R_INTERNAL_ERROR);
                        OPENSSL_free(tmp_wNAF);
                        goto err;
                    }
                    val_sub[i] = tmp_points;
                    tmp_points += pre_points_per_block;
                    pp += blocksize;
                }
                OPENSSL_free(tmp_wNAF);
            }
        }
    }

    /*
     * All points we precompute now go into a single array 'val'.
     * 'val_sub[i]' is a pointer to the subarray for the i-th point, or to a
     * subarray of 'pre_comp->points' if we already have precomputation.
     */
    val = OPENSSL_malloc((num_val + 1) * sizeof val[0]);
    if (val == NULL) {
        ECerr(EC_F_EC_WNAF_MUL, ERR_R_MALLOC_FAILURE);
        goto err;
    }
    val[num_val] = NULL;        /* pivot element */

    /* allocate points for precomputation */
    v = val;
    for (i = 0; i < num + num_scalar; i++) {
        val_sub[i] = v;
        for (j = 0; j < ((size_t)1 << (wsize[i] - 1)); j++) {
            *v = EC_POINT_new(group);
            if (*v == NULL)
                goto err;
            v++;
        }
    }
    if (!(v == val + num_val)) {
        ECerr(EC_F_EC_WNAF_MUL, ERR_R_INTERNAL_ERROR);
        goto err;
    }

    if ((tmp = EC_POINT_new(group)) == NULL)
        goto err;

    /*-
     * prepare precomputed values:
     *    val_sub[i][0] :=     points[i]
     *    val_sub[i][1] := 3 * points[i]
     *    val_sub[i][2] := 5 * points[i]
     *    ...
     */
    for (i = 0; i < num + num_scalar; i++) {
        if (i < num) {
            if (!EC_POINT_copy(val_sub[i][0], points[i]))
                goto err;
        } else {
            if (!EC_POINT_copy(val_sub[i][0], generator))
                goto err;
        }

        if (wsize[i] > 1) {
            if (!EC_POINT_dbl(group, tmp, val_sub[i][0], ctx))
                goto err;
            for (j = 1; j < ((size_t)1 << (wsize[i] - 1)); j++) {
                if (!EC_POINT_add
                    (group, val_sub[i][j], val_sub[i][j - 1], tmp, ctx))
                    goto err;
            }
        }
    }

    if (!EC_POINTs_make_affine(group, num_val, val, ctx))
        goto err;

    r_is_at_infinity = 1;

    for (k = max_len - 1; k >= 0; k--) {
        if (!r_is_at_infinity) {
            if (!EC_POINT_dbl(group, r, r, ctx))
                goto err;
        }

        for (i = 0; i < totalnum; i++) {
            if (wNAF_len[i] > (size_t)k) {
                int digit = wNAF[i][k];
                int is_neg;

                if (digit) {
                    is_neg = digit < 0;

                    if (is_neg)
                        digit = -digit;

                    if (is_neg != r_is_inverted) {
                        if (!r_is_at_infinity) {
                            if (!EC_POINT_invert(group, r, ctx))
                                goto err;
                        }
                        r_is_inverted = !r_is_inverted;
                    }

                    /* digit > 0 */

                    if (r_is_at_infinity) {
                        if (!EC_POINT_copy(r, val_sub[i][digit >> 1]))
                            goto err;
                        r_is_at_infinity = 0;
                    } else {
                        if (!EC_POINT_add
                            (group, r, r, val_sub[i][digit >> 1], ctx))
                            goto err;
                    }
                }
            }
        }
    }

    if (r_is_at_infinity) {
        if (!EC_POINT_set_to_infinity(group, r))
            goto err;
    } else {
        if (r_is_inverted)
            if (!EC_POINT_invert(group, r, ctx))
                goto err;
    }

    ret = 1;

 err:
    BN_CTX_free(new_ctx);
    EC_POINT_free(tmp);
    OPENSSL_free(wsize);
    OPENSSL_free(wNAF_len);
    if (wNAF != NULL) {
        signed char **w;

        for (w = wNAF; *w != NULL; w++)
            OPENSSL_free(*w);

        OPENSSL_free(wNAF);
    }
    if (val != NULL) {
        for (v = val; *v != NULL; v++)
            EC_POINT_clear_free(*v);

        OPENSSL_free(val);
    }
    OPENSSL_free(val_sub);
    return ret;
}

/*-
 * ec_wNAF_precompute_mult()
 * creates an EC_PRE_COMP object with preprecomputed multiples of the generator
 * for use with wNAF splitting as implemented in ec_wNAF_mul().
 *
 * 'pre_comp->points' is an array of multiples of the generator
 * of the following form:
 * points[0] =     generator;
 * points[1] = 3 * generator;
 * ...
 * points[2^(w-1)-1] =     (2^(w-1)-1) * generator;
 * points[2^(w-1)]   =     2^blocksize * generator;
 * points[2^(w-1)+1] = 3 * 2^blocksize * generator;
 * ...
 * points[2^(w-1)*(numblocks-1)-1] = (2^(w-1)) *  2^(blocksize*(numblocks-2)) * generator
 * points[2^(w-1)*(numblocks-1)]   =              2^(blocksize*(numblocks-1)) * generator
 * ...
 * points[2^(w-1)*numblocks-1]     = (2^(w-1)) *  2^(blocksize*(numblocks-1)) * generator
 * points[2^(w-1)*numblocks]       = NULL
 */
int ec_wNAF_precompute_mult(EC_GROUP *group, BN_CTX *ctx)
{
    const EC_POINT *generator;
    EC_POINT *tmp_point = NULL, *base = NULL, **var;
    BN_CTX *new_ctx = NULL;
    const BIGNUM *order;
    size_t i, bits, w, pre_points_per_block, blocksize, numblocks, num;
    EC_POINT **points = NULL;
    EC_PRE_COMP *pre_comp;
    int ret = 0;

    /* if there is an old EC_PRE_COMP object, throw it away */
    EC_pre_comp_free(group);
    if ((pre_comp = ec_pre_comp_new(group)) == NULL)
        return 0;

    generator = EC_GROUP_get0_generator(group);
    if (generator == NULL) {
        ECerr(EC_F_EC_WNAF_PRECOMPUTE_MULT, EC_R_UNDEFINED_GENERATOR);
        goto err;
    }

    if (ctx == NULL) {
        ctx = new_ctx = BN_CTX_new();
        if (ctx == NULL)
            goto err;
    }

    BN_CTX_start(ctx);

    order = EC_GROUP_get0_order(group);
    if (order == NULL)
        goto err;
    if (BN_is_zero(order)) {
        ECerr(EC_F_EC_WNAF_PRECOMPUTE_MULT, EC_R_UNKNOWN_ORDER);
        goto err;
    }

    bits = BN_num_bits(order);
    /*
     * The following parameters mean we precompute (approximately) one point
     * per bit. TBD: The combination 8, 4 is perfect for 160 bits; for other
     * bit lengths, other parameter combinations might provide better
     * efficiency.
     */
    blocksize = 8;
    w = 4;
    if (EC_window_bits_for_scalar_size(bits) > w) {
        /* let's not make the window too small ... */
        w = EC_window_bits_for_scalar_size(bits);
    }

    numblocks = (bits + blocksize - 1) / blocksize; /* max. number of blocks
                                                     * to use for wNAF
                                                     * splitting */

    pre_points_per_block = (size_t)1 << (w - 1);
    num = pre_points_per_block * numblocks; /* number of points to compute
                                             * and store */

    points = OPENSSL_malloc(sizeof(*points) * (num + 1));
    if (points == NULL) {
        ECerr(EC_F_EC_WNAF_PRECOMPUTE_MULT, ERR_R_MALLOC_FAILURE);
        goto err;
    }

    var = points;
    var[num] = NULL;            /* pivot */
    for (i = 0; i < num; i++) {
        if ((var[i] = EC_POINT_new(group)) == NULL) {
            ECerr(EC_F_EC_WNAF_PRECOMPUTE_MULT, ERR_R_MALLOC_FAILURE);
            goto err;
        }
    }

    if ((tmp_point = EC_POINT_new(group)) == NULL
        || (base = EC_POINT_new(group)) == NULL) {
        ECerr(EC_F_EC_WNAF_PRECOMPUTE_MULT, ERR_R_MALLOC_FAILURE);
        goto err;
    }

    if (!EC_POINT_copy(base, generator))
        goto err;

    /* do the precomputation */
    for (i = 0; i < numblocks; i++) {
        size_t j;

        if (!EC_POINT_dbl(group, tmp_point, base, ctx))
            goto err;

        if (!EC_POINT_copy(*var++, base))
            goto err;

        for (j = 1; j < pre_points_per_block; j++, var++) {
            /*
             * calculate odd multiples of the current base point
             */
            if (!EC_POINT_add(group, *var, tmp_point, *(var - 1), ctx))
                goto err;
        }

        if (i < numblocks - 1) {
            /*
             * get the next base (multiply current one by 2^blocksize)
             */
            size_t k;

            if (blocksize <= 2) {
                ECerr(EC_F_EC_WNAF_PRECOMPUTE_MULT, ERR_R_INTERNAL_ERROR);
                goto err;
            }

            if (!EC_POINT_dbl(group, base, tmp_point, ctx))
                goto err;
            for (k = 2; k < blocksize; k++) {
                if (!EC_POINT_dbl(group, base, base, ctx))
                    goto err;
            }
        }
    }

    if (!EC_POINTs_make_affine(group, num, points, ctx))
        goto err;

    pre_comp->group = group;
    pre_comp->blocksize = blocksize;
    pre_comp->numblocks = numblocks;
    pre_comp->w = w;
    pre_comp->points = points;
    points = NULL;
    pre_comp->num = num;
    SETPRECOMP(group, ec, pre_comp);
    pre_comp = NULL;
    ret = 1;

 err:
    if (ctx != NULL)
        BN_CTX_end(ctx);
    BN_CTX_free(new_ctx);
    EC_ec_pre_comp_free(pre_comp);
    if (points) {
        EC_POINT **p;

        for (p = points; *p != NULL; p++)
            EC_POINT_free(*p);
        OPENSSL_free(points);
    }
    EC_POINT_free(tmp_point);
    EC_POINT_free(base);
    return ret;
}

int ec_wNAF_have_precompute_mult(const EC_GROUP *group)
{
    return HAVEPRECOMP(group, ec);
}
Commit	Line	Data
35b73a1f	1	/*
4f22f405	2	* Copyright 2001-2016 The OpenSSL Project Authors. All Rights Reserved.
aa8f3d76	3	* Copyright (c) 2002, Oracle and/or its affiliates. All rights reserved
65e81670	4	*
4f22f405 RS	5	* Licensed under the OpenSSL license (the "License"). You may not use
	6	* this file except in compliance with the License. You can obtain a copy
	7	* in the file LICENSE in the source distribution or at
	8	* https://www.openssl.org/source/license.html
65e81670	9	*/
4f22f405	10
28f573a2	11	#include <string.h>
48fe4d62 BM	12	#include <openssl/err.h>
48fe4d62 BM	13
9b398ef2	14	#include "internal/cryptlib.h"
5784a521	15	#include "internal/bn_int.h"
65e81670	16	#include "ec_lcl.h"
48fe4d62	17
37c660ff	18	/*
0d4fb843	19	* This file implements the wNAF-based interleaving multi-exponentiation method
dea0eb2c RS	20	* Formerly at:
	21	* http://www.informatik.tu-darmstadt.de/TI/Mitarbeiter/moeller.html#multiexp
	22	* You might now find it here:
	23	* http://link.springer.com/chapter/10.1007%2F3-540-45537-X_13
	24	* http://www.bmoeller.de/pdf/TI-01-08.multiexp.pdf
	25	* For multiplication with precomputation, we use wNAF splitting, formerly at:
	26	* http://www.informatik.tu-darmstadt.de/TI/Mitarbeiter/moeller.html#fastexp
37c660ff	27	*/
48fe4d62	28
37c660ff	29	/* structure for precomputed multiples of the generator */
3aef36ff	30	struct ec_pre_comp_st {
0f113f3e MC	31	const EC_GROUP group; / parent EC_GROUP object */
	32	size_t blocksize; /* block size for wNAF splitting */
	33	size_t numblocks; /* max. number of blocks for which we have
	34	* precomputation */
	35	size_t w; /* window size */
	36	EC_POINT *points; / array with pre-calculated multiples of
	37	* generator: 'num' pointers to EC_POINT
	38	* objects followed by a NULL */
	39	size_t num; /* numblocks * 2^(w-1) */
2f545ae4	40	CRYPTO_REF_COUNT references;
9b398ef2	41	CRYPTO_RWLOCK *lock;
3aef36ff	42	};
37c660ff BM	43
37c660ff BM	44	static EC_PRE_COMP ec_pre_comp_new(const EC_GROUP group)
0f113f3e MC	45	{
	46	EC_PRE_COMP *ret = NULL;
	47
	48	if (!group)
	49	return NULL;
	50
64b25758	51	ret = OPENSSL_zalloc(sizeof(*ret));
90945fa3	52	if (ret == NULL) {
0f113f3e MC	53	ECerr(EC_F_EC_PRE_COMP_NEW, ERR_R_MALLOC_FAILURE);
	54	return ret;
	55	}
9b398ef2	56
0f113f3e MC	57	ret->group = group;
0f113f3e MC	58	ret->blocksize = 8; /* default */
0f113f3e	59	ret->w = 4; /* default */
0f113f3e	60	ret->references = 1;
9b398ef2 AG	61
	62	ret->lock = CRYPTO_THREAD_lock_new();
	63	if (ret->lock == NULL) {
	64	ECerr(EC_F_EC_PRE_COMP_NEW, ERR_R_MALLOC_FAILURE);
	65	OPENSSL_free(ret);
	66	return NULL;
	67	}
0f113f3e MC	68	return ret;
0f113f3e MC	69	}
37c660ff	70
3aef36ff	71	EC_PRE_COMP EC_ec_pre_comp_dup(EC_PRE_COMP pre)
0f113f3e	72	{
9b398ef2	73	int i;
3aef36ff	74	if (pre != NULL)
2f545ae4	75	CRYPTO_UP_REF(&pre->references, &i, pre->lock);
3aef36ff	76	return pre;
0f113f3e	77	}
37c660ff	78
3aef36ff	79	void EC_ec_pre_comp_free(EC_PRE_COMP *pre)
0f113f3e	80	{
9b398ef2 AG	81	int i;
	82
	83	if (pre == NULL)
	84	return;
	85
2f545ae4	86	CRYPTO_DOWN_REF(&pre->references, &i, pre->lock);
9b398ef2 AG	87	REF_PRINT_COUNT("EC_ec", pre);
9b398ef2 AG	88	if (i > 0)
0f113f3e	89	return;
9b398ef2	90	REF_ASSERT_ISNT(i < 0);
ba729265	91
3aef36ff RS	92	if (pre->points != NULL) {
3aef36ff RS	93	EC_POINT **pts;
37c660ff	94
3aef36ff RS	95	for (pts = pre->points; *pts != NULL; pts++)
3aef36ff RS	96	EC_POINT_free(*pts);
0f113f3e MC	97	OPENSSL_free(pre->points);
0f113f3e MC	98	}
9b398ef2	99	CRYPTO_THREAD_lock_free(pre->lock);
0f113f3e MC	100	OPENSSL_free(pre);
0f113f3e MC	101	}
37c660ff	102
0f113f3e MC	103	/*
	104	* TODO: table should be optimised for the wNAF-based implementation,
	105	* sometimes smaller windows will give better performance (thus the
	106	* boundaries should be increased)
c05940ed	107	*/
3ba1f111	108	#define EC_window_bits_for_scalar_size(b) \
0f113f3e MC	109	((size_t) \
	110	((b) >= 2000 ? 6 : \
	111	(b) >= 800 ? 5 : \
	112	(b) >= 300 ? 4 : \
	113	(b) >= 70 ? 3 : \
	114	(b) >= 20 ? 2 : \
	115	1))
3ba1f111	116
c80fd6b2 MC	117	/*-
c80fd6b2 MC	118	* Compute
3ba1f111 BM	119	* \sum scalars[i]*points[i],
	120	* also including
	121	* scalar*generator
	122	* in the addition if scalar != NULL
	123	*/
7793f30e	124	int ec_wNAF_mul(const EC_GROUP group, EC_POINT r, const BIGNUM *scalar,
0f113f3e MC	125	size_t num, const EC_POINT points[], const BIGNUM scalars[],
	126	BN_CTX *ctx)
	127	{
	128	BN_CTX *new_ctx = NULL;
	129	const EC_POINT *generator = NULL;
	130	EC_POINT *tmp = NULL;
	131	size_t totalnum;
	132	size_t blocksize = 0, numblocks = 0; /* for wNAF splitting */
	133	size_t pre_points_per_block = 0;
	134	size_t i, j;
	135	int k;
	136	int r_is_inverted = 0;
	137	int r_is_at_infinity = 1;
	138	size_t wsize = NULL; / individual window sizes */
	139	signed char *wNAF = NULL; / individual wNAFs */
	140	size_t *wNAF_len = NULL;
	141	size_t max_len = 0;
	142	size_t num_val;
	143	EC_POINT *val = NULL; / precomputation */
	144	EC_POINT **v;
	145	EC_POINT **val_sub = NULL; / pointers to sub-arrays of 'val' or
	146	* 'pre_comp->points' */
	147	const EC_PRE_COMP *pre_comp = NULL;
	148	int num_scalar = 0; /* flag: will be set to 1 if 'scalar' must be
	149	* treated like other scalars, i.e.
	150	* precomputation is not available */
	151	int ret = 0;
	152
	153	if (group->meth != r->meth) {
	154	ECerr(EC_F_EC_WNAF_MUL, EC_R_INCOMPATIBLE_OBJECTS);
	155	return 0;
	156	}
	157
	158	if ((scalar == NULL) && (num == 0)) {
	159	return EC_POINT_set_to_infinity(group, r);
	160	}
	161
	162	for (i = 0; i < num; i++) {
	163	if (group->meth != points[i]->meth) {
	164	ECerr(EC_F_EC_WNAF_MUL, EC_R_INCOMPATIBLE_OBJECTS);
	165	return 0;
	166	}
	167	}
	168
	169	if (ctx == NULL) {
	170	ctx = new_ctx = BN_CTX_new();
	171	if (ctx == NULL)
	172	goto err;
	173	}
	174
	175	if (scalar != NULL) {
	176	generator = EC_GROUP_get0_generator(group);
	177	if (generator == NULL) {
	178	ECerr(EC_F_EC_WNAF_MUL, EC_R_UNDEFINED_GENERATOR);
	179	goto err;
	180	}
	181
	182	/* look if we can use precomputed multiples of generator */
	183
3aef36ff	184	pre_comp = group->pre_comp.ec;
0f113f3e MC	185	if (pre_comp && pre_comp->numblocks
	186	&& (EC_POINT_cmp(group, generator, pre_comp->points[0], ctx) ==
	187	0)) {
	188	blocksize = pre_comp->blocksize;
	189
	190	/*
	191	* determine maximum number of blocks that wNAF splitting may
	192	* yield (NB: maximum wNAF length is bit length plus one)
	193	*/
	194	numblocks = (BN_num_bits(scalar) / blocksize) + 1;
	195
	196	/*
	197	* we cannot use more blocks than we have precomputation for
	198	*/
	199	if (numblocks > pre_comp->numblocks)
	200	numblocks = pre_comp->numblocks;
	201
	202	pre_points_per_block = (size_t)1 << (pre_comp->w - 1);
	203
	204	/* check that pre_comp looks sane */
	205	if (pre_comp->num != (pre_comp->numblocks * pre_points_per_block)) {
	206	ECerr(EC_F_EC_WNAF_MUL, ERR_R_INTERNAL_ERROR);
	207	goto err;
	208	}
	209	} else {
	210	/* can't use precomputation */
	211	pre_comp = NULL;
	212	numblocks = 1;
	213	num_scalar = 1; /* treat 'scalar' like 'num'-th element of
	214	* 'scalars' */
	215	}
	216	}
	217
	218	totalnum = num + numblocks;
	219
	220	wsize = OPENSSL_malloc(totalnum * sizeof wsize[0]);
	221	wNAF_len = OPENSSL_malloc(totalnum * sizeof wNAF_len[0]);
	222	wNAF = OPENSSL_malloc((totalnum + 1) * sizeof wNAF[0]); /* includes space
	223	* for pivot */
	224	val_sub = OPENSSL_malloc(totalnum * sizeof val_sub[0]);
	225
	226	/* Ensure wNAF is initialised in case we end up going to err */
90945fa3	227	if (wNAF != NULL)
0f113f3e MC	228	wNAF[0] = NULL; /* preliminary pivot */
0f113f3e MC	229
90945fa3	230	if (wsize == NULL \|\| wNAF_len == NULL \|\| wNAF == NULL \|\| val_sub == NULL) {
0f113f3e MC	231	ECerr(EC_F_EC_WNAF_MUL, ERR_R_MALLOC_FAILURE);
	232	goto err;
	233	}
	234
	235	/*
	236	* num_val will be the total number of temporarily precomputed points
	237	*/
	238	num_val = 0;
	239
	240	for (i = 0; i < num + num_scalar; i++) {
	241	size_t bits;
	242
	243	bits = i < num ? BN_num_bits(scalars[i]) : BN_num_bits(scalar);
	244	wsize[i] = EC_window_bits_for_scalar_size(bits);
	245	num_val += (size_t)1 << (wsize[i] - 1);
	246	wNAF[i + 1] = NULL; /* make sure we always have a pivot */
	247	wNAF[i] =
	248	bn_compute_wNAF((i < num ? scalars[i] : scalar), wsize[i],
	249	&wNAF_len[i]);
	250	if (wNAF[i] == NULL)
	251	goto err;
	252	if (wNAF_len[i] > max_len)
	253	max_len = wNAF_len[i];
	254	}
	255
	256	if (numblocks) {
	257	/* we go here iff scalar != NULL */
	258
	259	if (pre_comp == NULL) {
	260	if (num_scalar != 1) {
	261	ECerr(EC_F_EC_WNAF_MUL, ERR_R_INTERNAL_ERROR);
	262	goto err;
	263	}
	264	/* we have already generated a wNAF for 'scalar' */
	265	} else {
	266	signed char *tmp_wNAF = NULL;
	267	size_t tmp_len = 0;
	268
	269	if (num_scalar != 0) {
	270	ECerr(EC_F_EC_WNAF_MUL, ERR_R_INTERNAL_ERROR);
	271	goto err;
	272	}
	273
	274	/*
	275	* use the window size for which we have precomputation
	276	*/
	277	wsize[num] = pre_comp->w;
	278	tmp_wNAF = bn_compute_wNAF(scalar, wsize[num], &tmp_len);
	279	if (!tmp_wNAF)
	280	goto err;
	281
	282	if (tmp_len <= max_len) {
	283	/*
	284	* One of the other wNAFs is at least as long as the wNAF
	285	* belonging to the generator, so wNAF splitting will not buy
	286	* us anything.
	287	*/
	288
	289	numblocks = 1;
	290	totalnum = num + 1; /* don't use wNAF splitting */
	291	wNAF[num] = tmp_wNAF;
	292	wNAF[num + 1] = NULL;
	293	wNAF_len[num] = tmp_len;
0f113f3e MC	294	/*
	295	* pre_comp->points starts with the points that we need here:
	296	*/
	297	val_sub[num] = pre_comp->points;
	298	} else {
	299	/*
	300	* don't include tmp_wNAF directly into wNAF array - use wNAF
	301	* splitting and include the blocks
	302	*/
	303
	304	signed char *pp;
	305	EC_POINT **tmp_points;
	306
	307	if (tmp_len < numblocks * blocksize) {
	308	/*
	309	* possibly we can do with fewer blocks than estimated
	310	*/
	311	numblocks = (tmp_len + blocksize - 1) / blocksize;
	312	if (numblocks > pre_comp->numblocks) {
	313	ECerr(EC_F_EC_WNAF_MUL, ERR_R_INTERNAL_ERROR);
0e9eb1a5	314	OPENSSL_free(tmp_wNAF);
0f113f3e MC	315	goto err;
	316	}
	317	totalnum = num + numblocks;
	318	}
	319
	320	/* split wNAF in 'numblocks' parts */
	321	pp = tmp_wNAF;
	322	tmp_points = pre_comp->points;
	323
	324	for (i = num; i < totalnum; i++) {
	325	if (i < totalnum - 1) {
	326	wNAF_len[i] = blocksize;
	327	if (tmp_len < blocksize) {
	328	ECerr(EC_F_EC_WNAF_MUL, ERR_R_INTERNAL_ERROR);
0e9eb1a5	329	OPENSSL_free(tmp_wNAF);
0f113f3e MC	330	goto err;
	331	}
	332	tmp_len -= blocksize;
	333	} else
	334	/*
	335	* last block gets whatever is left (this could be
	336	* more or less than 'blocksize'!)
	337	*/
	338	wNAF_len[i] = tmp_len;
	339
	340	wNAF[i + 1] = NULL;
	341	wNAF[i] = OPENSSL_malloc(wNAF_len[i]);
	342	if (wNAF[i] == NULL) {
	343	ECerr(EC_F_EC_WNAF_MUL, ERR_R_MALLOC_FAILURE);
	344	OPENSSL_free(tmp_wNAF);
	345	goto err;
	346	}
	347	memcpy(wNAF[i], pp, wNAF_len[i]);
	348	if (wNAF_len[i] > max_len)
	349	max_len = wNAF_len[i];
	350
	351	if (*tmp_points == NULL) {
	352	ECerr(EC_F_EC_WNAF_MUL, ERR_R_INTERNAL_ERROR);
	353	OPENSSL_free(tmp_wNAF);
	354	goto err;
	355	}
	356	val_sub[i] = tmp_points;
	357	tmp_points += pre_points_per_block;
	358	pp += blocksize;
	359	}
	360	OPENSSL_free(tmp_wNAF);
	361	}
	362	}
	363	}
	364
	365	/*
	366	* All points we precompute now go into a single array 'val'.
	367	* 'val_sub[i]' is a pointer to the subarray for the i-th point, or to a
	368	* subarray of 'pre_comp->points' if we already have precomputation.
	369	*/
	370	val = OPENSSL_malloc((num_val + 1) * sizeof val[0]);
	371	if (val == NULL) {
	372	ECerr(EC_F_EC_WNAF_MUL, ERR_R_MALLOC_FAILURE);
	373	goto err;
	374	}
	375	val[num_val] = NULL; /* pivot element */
	376
	377	/* allocate points for precomputation */
	378	v = val;
	379	for (i = 0; i < num + num_scalar; i++) {
	380	val_sub[i] = v;
	381	for (j = 0; j < ((size_t)1 << (wsize[i] - 1)); j++) {
	382	*v = EC_POINT_new(group);
	383	if (*v == NULL)
	384	goto err;
	385	v++;
	386	}
	387	}
	388	if (!(v == val + num_val)) {
	389	ECerr(EC_F_EC_WNAF_MUL, ERR_R_INTERNAL_ERROR);
	390	goto err;
	391	}
	392
75ebbd9a	393	if ((tmp = EC_POINT_new(group)) == NULL)
0f113f3e MC	394	goto err;
0f113f3e MC	395
50e735f9 MC	396	/*-
	397	* prepare precomputed values:
	398	* val_sub[i][0] := points[i]
	399	* val_sub[i][1] := 3 * points[i]
	400	* val_sub[i][2] := 5 * points[i]
	401	* ...
	402	*/
0f113f3e MC	403	for (i = 0; i < num + num_scalar; i++) {
	404	if (i < num) {
	405	if (!EC_POINT_copy(val_sub[i][0], points[i]))
	406	goto err;
	407	} else {
	408	if (!EC_POINT_copy(val_sub[i][0], generator))
	409	goto err;
	410	}
	411
	412	if (wsize[i] > 1) {
	413	if (!EC_POINT_dbl(group, tmp, val_sub[i][0], ctx))
	414	goto err;
	415	for (j = 1; j < ((size_t)1 << (wsize[i] - 1)); j++) {
	416	if (!EC_POINT_add
	417	(group, val_sub[i][j], val_sub[i][j - 1], tmp, ctx))
	418	goto err;
	419	}
	420	}
	421	}
	422
0f113f3e MC	423	if (!EC_POINTs_make_affine(group, num_val, val, ctx))
0f113f3e MC	424	goto err;
3ba1f111	425
0f113f3e MC	426	r_is_at_infinity = 1;
	427
	428	for (k = max_len - 1; k >= 0; k--) {
	429	if (!r_is_at_infinity) {
	430	if (!EC_POINT_dbl(group, r, r, ctx))
	431	goto err;
	432	}
	433
	434	for (i = 0; i < totalnum; i++) {
	435	if (wNAF_len[i] > (size_t)k) {
	436	int digit = wNAF[i][k];
	437	int is_neg;
	438
	439	if (digit) {
	440	is_neg = digit < 0;
	441
	442	if (is_neg)
	443	digit = -digit;
	444
	445	if (is_neg != r_is_inverted) {
	446	if (!r_is_at_infinity) {
	447	if (!EC_POINT_invert(group, r, ctx))
	448	goto err;
	449	}
	450	r_is_inverted = !r_is_inverted;
	451	}
	452
	453	/* digit > 0 */
	454
	455	if (r_is_at_infinity) {
	456	if (!EC_POINT_copy(r, val_sub[i][digit >> 1]))
	457	goto err;
	458	r_is_at_infinity = 0;
	459	} else {
	460	if (!EC_POINT_add
	461	(group, r, r, val_sub[i][digit >> 1], ctx))
	462	goto err;
	463	}
	464	}
	465	}
	466	}
	467	}
	468
	469	if (r_is_at_infinity) {
	470	if (!EC_POINT_set_to_infinity(group, r))
	471	goto err;
	472	} else {
	473	if (r_is_inverted)
	474	if (!EC_POINT_invert(group, r, ctx))
	475	goto err;
	476	}
	477
	478	ret = 1;
3ba1f111 BM	479
3ba1f111 BM	480	err:
23a1d5e9	481	BN_CTX_free(new_ctx);
8fdc3734	482	EC_POINT_free(tmp);
b548a1f1 RS	483	OPENSSL_free(wsize);
b548a1f1 RS	484	OPENSSL_free(wNAF_len);
0f113f3e MC	485	if (wNAF != NULL) {
	486	signed char **w;
	487
	488	for (w = wNAF; *w != NULL; w++)
	489	OPENSSL_free(*w);
	490
	491	OPENSSL_free(wNAF);
	492	}
	493	if (val != NULL) {
	494	for (v = val; *v != NULL; v++)
	495	EC_POINT_clear_free(*v);
	496
	497	OPENSSL_free(val);
	498	}
b548a1f1	499	OPENSSL_free(val_sub);
0f113f3e MC	500	return ret;
0f113f3e MC	501	}
38374911	502
1d97c843 TH	503	/*-
1d97c843 TH	504	* ec_wNAF_precompute_mult()
37c660ff BM	505	* creates an EC_PRE_COMP object with preprecomputed multiples of the generator
37c660ff BM	506	* for use with wNAF splitting as implemented in ec_wNAF_mul().
0f113f3e	507	*
37c660ff BM	508	* 'pre_comp->points' is an array of multiples of the generator
	509	* of the following form:
	510	* points[0] = generator;
	511	* points[1] = 3 * generator;
	512	* ...
	513	* points[2^(w-1)-1] = (2^(w-1)-1) * generator;
	514	* points[2^(w-1)] = 2^blocksize * generator;
	515	* points[2^(w-1)+1] = 3 * 2^blocksize * generator;
	516	* ...
	517	* points[2^(w-1)(numblocks-1)-1] = (2^(w-1)) 2^(blocksize(numblocks-2)) generator
	518	* points[2^(w-1)(numblocks-1)] = 2^(blocksize(numblocks-1)) * generator
	519	* ...
	520	* points[2^(w-1)numblocks-1] = (2^(w-1)) 2^(blocksize(numblocks-1)) generator
	521	* points[2^(w-1)*numblocks] = NULL
7793f30e	522	*/
7793f30e	523	int ec_wNAF_precompute_mult(EC_GROUP group, BN_CTX ctx)
0f113f3e MC	524	{
	525	const EC_POINT *generator;
	526	EC_POINT tmp_point = NULL, base = NULL, **var;
	527	BN_CTX *new_ctx = NULL;
be2e334f	528	const BIGNUM *order;
0f113f3e MC	529	size_t i, bits, w, pre_points_per_block, blocksize, numblocks, num;
	530	EC_POINT **points = NULL;
	531	EC_PRE_COMP *pre_comp;
	532	int ret = 0;
	533
	534	/* if there is an old EC_PRE_COMP object, throw it away */
2c52ac9b	535	EC_pre_comp_free(group);
0f113f3e MC	536	if ((pre_comp = ec_pre_comp_new(group)) == NULL)
	537	return 0;
	538
	539	generator = EC_GROUP_get0_generator(group);
	540	if (generator == NULL) {
	541	ECerr(EC_F_EC_WNAF_PRECOMPUTE_MULT, EC_R_UNDEFINED_GENERATOR);
	542	goto err;
	543	}
	544
	545	if (ctx == NULL) {
	546	ctx = new_ctx = BN_CTX_new();
	547	if (ctx == NULL)
	548	goto err;
	549	}
	550
	551	BN_CTX_start(ctx);
0f113f3e	552
be2e334f DSH	553	order = EC_GROUP_get0_order(group);
be2e334f DSH	554	if (order == NULL)
0f113f3e MC	555	goto err;
	556	if (BN_is_zero(order)) {
	557	ECerr(EC_F_EC_WNAF_PRECOMPUTE_MULT, EC_R_UNKNOWN_ORDER);
	558	goto err;
	559	}
	560
	561	bits = BN_num_bits(order);
	562	/*
	563	* The following parameters mean we precompute (approximately) one point
	564	* per bit. TBD: The combination 8, 4 is perfect for 160 bits; for other
	565	* bit lengths, other parameter combinations might provide better
	566	* efficiency.
	567	*/
	568	blocksize = 8;
	569	w = 4;
	570	if (EC_window_bits_for_scalar_size(bits) > w) {
	571	/* let's not make the window too small ... */
	572	w = EC_window_bits_for_scalar_size(bits);
	573	}
	574
	575	numblocks = (bits + blocksize - 1) / blocksize; /* max. number of blocks
	576	* to use for wNAF
	577	* splitting */
	578
	579	pre_points_per_block = (size_t)1 << (w - 1);
	580	num = pre_points_per_block * numblocks; /* number of points to compute
	581	* and store */
	582
b4faea50	583	points = OPENSSL_malloc(sizeof(points) (num + 1));
90945fa3	584	if (points == NULL) {
0f113f3e MC	585	ECerr(EC_F_EC_WNAF_PRECOMPUTE_MULT, ERR_R_MALLOC_FAILURE);
	586	goto err;
	587	}
	588
	589	var = points;
	590	var[num] = NULL; /* pivot */
	591	for (i = 0; i < num; i++) {
	592	if ((var[i] = EC_POINT_new(group)) == NULL) {
	593	ECerr(EC_F_EC_WNAF_PRECOMPUTE_MULT, ERR_R_MALLOC_FAILURE);
	594	goto err;
	595	}
	596	}
	597
75ebbd9a RS	598	if ((tmp_point = EC_POINT_new(group)) == NULL
75ebbd9a RS	599	\|\| (base = EC_POINT_new(group)) == NULL) {
0f113f3e MC	600	ECerr(EC_F_EC_WNAF_PRECOMPUTE_MULT, ERR_R_MALLOC_FAILURE);
	601	goto err;
	602	}
	603
	604	if (!EC_POINT_copy(base, generator))
	605	goto err;
	606
	607	/* do the precomputation */
	608	for (i = 0; i < numblocks; i++) {
	609	size_t j;
	610
	611	if (!EC_POINT_dbl(group, tmp_point, base, ctx))
	612	goto err;
	613
	614	if (!EC_POINT_copy(*var++, base))
	615	goto err;
	616
	617	for (j = 1; j < pre_points_per_block; j++, var++) {
	618	/*
	619	* calculate odd multiples of the current base point
	620	*/
	621	if (!EC_POINT_add(group, var, tmp_point, (var - 1), ctx))
	622	goto err;
	623	}
	624
	625	if (i < numblocks - 1) {
	626	/*
	627	* get the next base (multiply current one by 2^blocksize)
	628	*/
	629	size_t k;
	630
	631	if (blocksize <= 2) {
	632	ECerr(EC_F_EC_WNAF_PRECOMPUTE_MULT, ERR_R_INTERNAL_ERROR);
	633	goto err;
	634	}
	635
	636	if (!EC_POINT_dbl(group, base, tmp_point, ctx))
	637	goto err;
	638	for (k = 2; k < blocksize; k++) {
	639	if (!EC_POINT_dbl(group, base, base, ctx))
	640	goto err;
	641	}
	642	}
	643	}
	644
	645	if (!EC_POINTs_make_affine(group, num, points, ctx))
	646	goto err;
	647
	648	pre_comp->group = group;
	649	pre_comp->blocksize = blocksize;
	650	pre_comp->numblocks = numblocks;
	651	pre_comp->w = w;
	652	pre_comp->points = points;
	653	points = NULL;
	654	pre_comp->num = num;
3aef36ff	655	SETPRECOMP(group, ec, pre_comp);
0f113f3e	656	pre_comp = NULL;
0f113f3e	657	ret = 1;
3aef36ff	658
38374911	659	err:
0f113f3e MC	660	if (ctx != NULL)
0f113f3e MC	661	BN_CTX_end(ctx);
23a1d5e9	662	BN_CTX_free(new_ctx);
3aef36ff	663	EC_ec_pre_comp_free(pre_comp);
0f113f3e MC	664	if (points) {
	665	EC_POINT **p;
	666
	667	for (p = points; *p != NULL; p++)
	668	EC_POINT_free(*p);
	669	OPENSSL_free(points);
	670	}
8fdc3734 RS	671	EC_POINT_free(tmp_point);
8fdc3734 RS	672	EC_POINT_free(base);
0f113f3e MC	673	return ret;
0f113f3e MC	674	}
7793f30e	675
37c660ff	676	int ec_wNAF_have_precompute_mult(const EC_GROUP *group)
0f113f3e	677	{
3aef36ff	678	return HAVEPRECOMP(group, ec);
0f113f3e	679	}