diff --git a/crypto/ec/wnaf.c b/crypto/ec/wnaf.c
new file mode 100644
index 0000000..b86107d
--- /dev/null
+++ b/crypto/ec/wnaf.c
@@ -0,0 +1,841 @@
+/* Originally written by Bodo Moeller for the OpenSSL project.
+ * ====================================================================
+ * Copyright (c) 1998-2005 The OpenSSL Project.  All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ *
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in
+ *    the documentation and/or other materials provided with the
+ *    distribution.
+ *
+ * 3. All advertising materials mentioning features or use of this
+ *    software must display the following acknowledgment:
+ *    "This product includes software developed by the OpenSSL Project
+ *    for use in the OpenSSL Toolkit. (http://www.openssl.org/)"
+ *
+ * 4. The names "OpenSSL Toolkit" and "OpenSSL Project" must not be used to
+ *    endorse or promote products derived from this software without
+ *    prior written permission. For written permission, please contact
+ *    openssl-core@openssl.org.
+ *
+ * 5. Products derived from this software may not be called "OpenSSL"
+ *    nor may "OpenSSL" appear in their names without prior written
+ *    permission of the OpenSSL Project.
+ *
+ * 6. Redistributions of any form whatsoever must retain the following
+ *    acknowledgment:
+ *    "This product includes software developed by the OpenSSL Project
+ *    for use in the OpenSSL Toolkit (http://www.openssl.org/)"
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE OpenSSL PROJECT ``AS IS'' AND ANY
+ * EXPRESSED OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
+ * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE OpenSSL PROJECT OR
+ * ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+ * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
+ * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
+ * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+ * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
+ * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
+ * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED
+ * OF THE POSSIBILITY OF SUCH DAMAGE.
+ * ====================================================================
+ *
+ * This product includes cryptographic software written by Eric Young
+ * (eay@cryptsoft.com).  This product includes software written by Tim
+ * Hudson (tjh@cryptsoft.com).
+ *
+ */
+/* ====================================================================
+ * Copyright 2002 Sun Microsystems, Inc. ALL RIGHTS RESERVED.
+ *
+ * Portions of the attached software ("Contribution") are developed by
+ * SUN MICROSYSTEMS, INC., and are contributed to the OpenSSL project.
+ *
+ * The Contribution is licensed pursuant to the OpenSSL open source
+ * license provided above.
+ *
+ * The elliptic curve binary polynomial software is originally written by
+ * Sheueling Chang Shantz and Douglas Stebila of Sun Microsystems
+ * Laboratories. */
+
+#include <openssl/ec.h>
+
+#include <openssl/bn.h>
+#include <openssl/err.h>
+#include <openssl/mem.h>
+
+#include "internal.h"
+
+
+/* This file implements the wNAF-based interleaving multi-exponentation method
+ * (<URL:http://www.informatik.tu-darmstadt.de/TI/Mitarbeiter/moeller.html#multiexp>);
+ * for multiplication with precomputation, we use wNAF splitting
+ * (<URL:http://www.informatik.tu-darmstadt.de/TI/Mitarbeiter/moeller.html#fastexp>).
+ * */
+
+/* structure for precomputed multiples of the generator */
+typedef 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) */
+  int references;
+} EC_PRE_COMP;
+
+static EC_PRE_COMP *ec_pre_comp_new(const EC_GROUP *group) {
+  EC_PRE_COMP *ret = NULL;
+
+  if (!group)
+    return NULL;
+
+  ret = (EC_PRE_COMP *)OPENSSL_malloc(sizeof(EC_PRE_COMP));
+  if (!ret) {
+    OPENSSL_PUT_ERROR(EC, ec_pre_comp_new, ERR_R_MALLOC_FAILURE);
+    return ret;
+  }
+  ret->group = group;
+  ret->blocksize = 8; /* default */
+  ret->numblocks = 0;
+  ret->w = 4; /* default */
+  ret->points = NULL;
+  ret->num = 0;
+  ret->references = 1;
+  return ret;
+}
+
+void *ec_pre_comp_dup(EC_PRE_COMP *pre_comp) {
+  if (pre_comp == NULL) {
+    return NULL;
+  }
+
+  CRYPTO_add(&pre_comp->references, 1, CRYPTO_LOCK_EC_PRE_COMP);
+  return pre_comp;
+}
+
+void ec_pre_comp_free(EC_PRE_COMP *pre_comp) {
+  int i;
+
+  if (!pre_comp) {
+    return;
+  }
+
+  i = CRYPTO_add(&pre_comp->references, -1, CRYPTO_LOCK_EC_PRE_COMP);
+  if (i > 0) {
+    return;
+  }
+
+  if (pre_comp->points) {
+    EC_POINT **p;
+
+    for (p = pre_comp->points; *p != NULL; p++) {
+      EC_POINT_free(*p);
+    }
+    OPENSSL_free(pre_comp->points);
+  }
+  OPENSSL_free(pre_comp);
+}
+
+
+/* Determine the modified width-(w+1) Non-Adjacent Form (wNAF) of 'scalar'.
+ * This is an array  r[]  of values that are either zero or odd with an
+ * absolute value less than  2^w  satisfying
+ *     scalar = \sum_j r[j]*2^j
+ * where at most one of any  w+1  consecutive digits is non-zero
+ * with the exception that the most significant digit may be only
+ * w-1 zeros away from that next non-zero digit.
+ */
+static signed char *compute_wNAF(const BIGNUM *scalar, int w, size_t *ret_len) {
+  int window_val;
+  int ok = 0;
+  signed char *r = NULL;
+  int sign = 1;
+  int bit, next_bit, mask;
+  size_t len = 0, j;
+
+  if (BN_is_zero(scalar)) {
+    r = OPENSSL_malloc(1);
+    if (!r) {
+      OPENSSL_PUT_ERROR(EC, compute_wNAF, ERR_R_MALLOC_FAILURE);
+      goto err;
+    }
+    r[0] = 0;
+    *ret_len = 1;
+    return r;
+  }
+
+  if (w <= 0 || w > 7) /* 'signed char' can represent integers with absolute
+                          values less than 2^7 */
+  {
+    OPENSSL_PUT_ERROR(EC, compute_wNAF, ERR_R_INTERNAL_ERROR);
+    goto err;
+  }
+  bit = 1 << w;        /* at most 128 */
+  next_bit = bit << 1; /* at most 256 */
+  mask = next_bit - 1; /* at most 255 */
+
+  if (BN_is_negative(scalar)) {
+    sign = -1;
+  }
+
+  if (scalar->d == NULL || scalar->top == 0) {
+    OPENSSL_PUT_ERROR(EC, compute_wNAF, ERR_R_INTERNAL_ERROR);
+    goto err;
+  }
+
+  len = BN_num_bits(scalar);
+  r = OPENSSL_malloc(
+      len +
+      1); /* modified wNAF may be one digit longer than binary representation
+           * (*ret_len will be set to the actual length, i.e. at most
+           * BN_num_bits(scalar) + 1) */
+  if (r == NULL) {
+    OPENSSL_PUT_ERROR(EC, compute_wNAF, ERR_R_MALLOC_FAILURE);
+    goto err;
+  }
+  window_val = scalar->d[0] & mask;
+  j = 0;
+  while ((window_val != 0) ||
+         (j + w + 1 < len)) /* if j+w+1 >= len, window_val will not increase */
+  {
+    int digit = 0;
+
+    /* 0 <= window_val <= 2^(w+1) */
+
+    if (window_val & 1) {
+      /* 0 < window_val < 2^(w+1) */
+
+      if (window_val & bit) {
+        digit = window_val - next_bit; /* -2^w < digit < 0 */
+
+#if 1 /* modified wNAF */
+        if (j + w + 1 >= len) {
+          /* special case for generating modified wNAFs:
+           * no new bits will be added into window_val,
+           * so using a positive digit here will decrease
+           * the total length of the representation */
+
+          digit = window_val & (mask >> 1); /* 0 < digit < 2^w */
+        }
+#endif
+      } else {
+        digit = window_val; /* 0 < digit < 2^w */
+      }
+
+      if (digit <= -bit || digit >= bit || !(digit & 1)) {
+        OPENSSL_PUT_ERROR(EC, compute_wNAF, ERR_R_INTERNAL_ERROR);
+        goto err;
+      }
+
+      window_val -= digit;
+
+      /* now window_val is 0 or 2^(w+1) in standard wNAF generation;
+       * for modified window NAFs, it may also be 2^w
+       */
+      if (window_val != 0 && window_val != next_bit && window_val != bit) {
+        OPENSSL_PUT_ERROR(EC, compute_wNAF, ERR_R_INTERNAL_ERROR);
+        goto err;
+      }
+    }
+
+    r[j++] = sign * digit;
+
+    window_val >>= 1;
+    window_val += bit * BN_is_bit_set(scalar, j + w);
+
+    if (window_val > next_bit) {
+      OPENSSL_PUT_ERROR(EC, compute_wNAF, ERR_R_INTERNAL_ERROR);
+      goto err;
+    }
+  }
+
+  if (j > len + 1) {
+    OPENSSL_PUT_ERROR(EC, compute_wNAF, ERR_R_INTERNAL_ERROR);
+    goto err;
+  }
+  len = j;
+  ok = 1;
+
+err:
+  if (!ok) {
+    OPENSSL_free(r);
+    r = NULL;
+  }
+  if (ok)
+    *ret_len = len;
+  return r;
+}
+
+
+/* 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) {
+    OPENSSL_PUT_ERROR(EC, 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) {
+      OPENSSL_PUT_ERROR(EC, 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) {
+      OPENSSL_PUT_ERROR(EC, ec_wNAF_mul, EC_R_UNDEFINED_GENERATOR);
+      goto err;
+    }
+
+    /* look if we can use precomputed multiples of generator */
+
+    pre_comp = group->pre_comp;
+
+    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)) {
+        OPENSSL_PUT_ERROR(EC, 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]);
+
+  if (!wsize || !wNAF_len || !wNAF || !val_sub) {
+    OPENSSL_PUT_ERROR(EC, ec_wNAF_mul, ERR_R_MALLOC_FAILURE);
+    goto err;
+  }
+
+  wNAF[0] = NULL; /* preliminary pivot */
+
+  /* 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] =
+        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) {
+        OPENSSL_PUT_ERROR(EC, 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) {
+        OPENSSL_PUT_ERROR(EC, 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 = 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;
+        if (tmp_len > max_len)
+          max_len = 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) {
+            OPENSSL_PUT_ERROR(EC, ec_wNAF_mul, ERR_R_INTERNAL_ERROR);
+            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) {
+              OPENSSL_PUT_ERROR(EC, ec_wNAF_mul, ERR_R_INTERNAL_ERROR);
+              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) {
+            OPENSSL_PUT_ERROR(EC, 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) {
+            OPENSSL_PUT_ERROR(EC, 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) {
+    OPENSSL_PUT_ERROR(EC, 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)) {
+    OPENSSL_PUT_ERROR(EC, ec_wNAF_mul, ERR_R_INTERNAL_ERROR);
+    goto err;
+  }
+
+  if (!(tmp = EC_POINT_new(group)))
+    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 1 /* optional; EC_window_bits_for_scalar_size assumes we do this step */
+  if (!EC_POINTs_make_affine(group, num_val, val, ctx))
+    goto err;
+#endif
+
+  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:
+  if (new_ctx != NULL)
+    BN_CTX_free(new_ctx);
+  if (tmp != NULL)
+    EC_POINT_free(tmp);
+  if (wsize != NULL)
+    OPENSSL_free(wsize);
+  if (wNAF_len != NULL)
+    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);
+  }
+  if (val_sub != NULL) {
+    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;
+  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 */
+  if (group->pre_comp) {
+    ec_pre_comp_free(group->pre_comp);
+    group->pre_comp = NULL;
+  }
+
+  if ((pre_comp = ec_pre_comp_new(group)) == NULL)
+    return 0;
+
+  generator = EC_GROUP_get0_generator(group);
+  if (generator == NULL) {
+    OPENSSL_PUT_ERROR(EC, 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 = BN_CTX_get(ctx);
+  if (order == NULL)
+    goto err;
+
+  if (!EC_GROUP_get_order(group, order, ctx))
+    goto err;
+  if (BN_is_zero(order)) {
+    OPENSSL_PUT_ERROR(EC, 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(EC_POINT *) * (num + 1));
+  if (!points) {
+    OPENSSL_PUT_ERROR(EC, 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) {
+      OPENSSL_PUT_ERROR(EC, ec_wNAF_precompute_mult, ERR_R_MALLOC_FAILURE);
+      goto err;
+    }
+  }
+
+  if (!(tmp_point = EC_POINT_new(group)) || !(base = EC_POINT_new(group))) {
+    OPENSSL_PUT_ERROR(EC, 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) {
+        OPENSSL_PUT_ERROR(EC, 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;
+
+  group->pre_comp = pre_comp;
+  pre_comp = NULL;
+
+  ret = 1;
+
+err:
+  if (ctx != NULL)
+    BN_CTX_end(ctx);
+  if (new_ctx != NULL)
+    BN_CTX_free(new_ctx);
+  if (pre_comp)
+    ec_pre_comp_free(pre_comp);
+  if (points) {
+    EC_POINT **p;
+
+    for (p = points; *p != NULL; p++)
+      EC_POINT_free(*p);
+    OPENSSL_free(points);
+  }
+  if (tmp_point)
+    EC_POINT_free(tmp_point);
+  if (base)
+    EC_POINT_free(base);
+  return ret;
+}
+
+
+int ec_wNAF_have_precompute_mult(const EC_GROUP *group) {
+  return group->pre_comp != NULL;
+}