Adam Langley | d9e397b | 2015-01-22 14:27:53 -0800 | [diff] [blame] | 1 | /* Originally written by Bodo Moeller for the OpenSSL project. |
| 2 | * ==================================================================== |
| 3 | * Copyright (c) 1998-2005 The OpenSSL Project. All rights reserved. |
| 4 | * |
| 5 | * Redistribution and use in source and binary forms, with or without |
| 6 | * modification, are permitted provided that the following conditions |
| 7 | * are met: |
| 8 | * |
| 9 | * 1. Redistributions of source code must retain the above copyright |
| 10 | * notice, this list of conditions and the following disclaimer. |
| 11 | * |
| 12 | * 2. Redistributions in binary form must reproduce the above copyright |
| 13 | * notice, this list of conditions and the following disclaimer in |
| 14 | * the documentation and/or other materials provided with the |
| 15 | * distribution. |
| 16 | * |
| 17 | * 3. All advertising materials mentioning features or use of this |
| 18 | * software must display the following acknowledgment: |
| 19 | * "This product includes software developed by the OpenSSL Project |
| 20 | * for use in the OpenSSL Toolkit. (http://www.openssl.org/)" |
| 21 | * |
| 22 | * 4. The names "OpenSSL Toolkit" and "OpenSSL Project" must not be used to |
| 23 | * endorse or promote products derived from this software without |
| 24 | * prior written permission. For written permission, please contact |
| 25 | * openssl-core@openssl.org. |
| 26 | * |
| 27 | * 5. Products derived from this software may not be called "OpenSSL" |
| 28 | * nor may "OpenSSL" appear in their names without prior written |
| 29 | * permission of the OpenSSL Project. |
| 30 | * |
| 31 | * 6. Redistributions of any form whatsoever must retain the following |
| 32 | * acknowledgment: |
| 33 | * "This product includes software developed by the OpenSSL Project |
| 34 | * for use in the OpenSSL Toolkit (http://www.openssl.org/)" |
| 35 | * |
| 36 | * THIS SOFTWARE IS PROVIDED BY THE OpenSSL PROJECT ``AS IS'' AND ANY |
| 37 | * EXPRESSED OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE |
| 38 | * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR |
| 39 | * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE OpenSSL PROJECT OR |
| 40 | * ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, |
| 41 | * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT |
| 42 | * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; |
| 43 | * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) |
| 44 | * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, |
| 45 | * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) |
| 46 | * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED |
| 47 | * OF THE POSSIBILITY OF SUCH DAMAGE. |
| 48 | * ==================================================================== |
| 49 | * |
| 50 | * This product includes cryptographic software written by Eric Young |
| 51 | * (eay@cryptsoft.com). This product includes software written by Tim |
| 52 | * Hudson (tjh@cryptsoft.com). |
| 53 | * |
| 54 | */ |
| 55 | /* ==================================================================== |
| 56 | * Copyright 2002 Sun Microsystems, Inc. ALL RIGHTS RESERVED. |
| 57 | * |
| 58 | * Portions of the attached software ("Contribution") are developed by |
| 59 | * SUN MICROSYSTEMS, INC., and are contributed to the OpenSSL project. |
| 60 | * |
| 61 | * The Contribution is licensed pursuant to the OpenSSL open source |
| 62 | * license provided above. |
| 63 | * |
| 64 | * The elliptic curve binary polynomial software is originally written by |
| 65 | * Sheueling Chang Shantz and Douglas Stebila of Sun Microsystems |
| 66 | * Laboratories. */ |
| 67 | |
| 68 | #include <openssl/ec.h> |
| 69 | |
| 70 | #include <string.h> |
| 71 | |
| 72 | #include <openssl/bn.h> |
| 73 | #include <openssl/err.h> |
| 74 | #include <openssl/mem.h> |
Adam Langley | e9ada86 | 2015-05-11 17:20:37 -0700 | [diff] [blame] | 75 | #include <openssl/thread.h> |
Adam Langley | d9e397b | 2015-01-22 14:27:53 -0800 | [diff] [blame] | 76 | |
| 77 | #include "internal.h" |
Adam Langley | f4e4272 | 2015-06-04 17:45:09 -0700 | [diff] [blame] | 78 | #include "../internal.h" |
Adam Langley | d9e397b | 2015-01-22 14:27:53 -0800 | [diff] [blame] | 79 | |
| 80 | |
| 81 | /* This file implements the wNAF-based interleaving multi-exponentation method |
| 82 | * (<URL:http://www.informatik.tu-darmstadt.de/TI/Mitarbeiter/moeller.html#multiexp>); |
Adam Langley | d9e397b | 2015-01-22 14:27:53 -0800 | [diff] [blame] | 83 | * */ |
| 84 | |
Adam Langley | d9e397b | 2015-01-22 14:27:53 -0800 | [diff] [blame] | 85 | /* Determine the modified width-(w+1) Non-Adjacent Form (wNAF) of 'scalar'. |
| 86 | * This is an array r[] of values that are either zero or odd with an |
| 87 | * absolute value less than 2^w satisfying |
| 88 | * scalar = \sum_j r[j]*2^j |
| 89 | * where at most one of any w+1 consecutive digits is non-zero |
| 90 | * with the exception that the most significant digit may be only |
| 91 | * w-1 zeros away from that next non-zero digit. |
| 92 | */ |
| 93 | static signed char *compute_wNAF(const BIGNUM *scalar, int w, size_t *ret_len) { |
| 94 | int window_val; |
| 95 | int ok = 0; |
| 96 | signed char *r = NULL; |
| 97 | int sign = 1; |
| 98 | int bit, next_bit, mask; |
| 99 | size_t len = 0, j; |
| 100 | |
| 101 | if (BN_is_zero(scalar)) { |
| 102 | r = OPENSSL_malloc(1); |
| 103 | if (!r) { |
Kenny Root | b849459 | 2015-09-25 02:29:14 +0000 | [diff] [blame] | 104 | OPENSSL_PUT_ERROR(EC, ERR_R_MALLOC_FAILURE); |
Adam Langley | d9e397b | 2015-01-22 14:27:53 -0800 | [diff] [blame] | 105 | goto err; |
| 106 | } |
| 107 | r[0] = 0; |
| 108 | *ret_len = 1; |
| 109 | return r; |
| 110 | } |
| 111 | |
| 112 | if (w <= 0 || w > 7) /* 'signed char' can represent integers with absolute |
| 113 | values less than 2^7 */ |
| 114 | { |
Kenny Root | b849459 | 2015-09-25 02:29:14 +0000 | [diff] [blame] | 115 | OPENSSL_PUT_ERROR(EC, ERR_R_INTERNAL_ERROR); |
Adam Langley | d9e397b | 2015-01-22 14:27:53 -0800 | [diff] [blame] | 116 | goto err; |
| 117 | } |
| 118 | bit = 1 << w; /* at most 128 */ |
| 119 | next_bit = bit << 1; /* at most 256 */ |
| 120 | mask = next_bit - 1; /* at most 255 */ |
| 121 | |
| 122 | if (BN_is_negative(scalar)) { |
| 123 | sign = -1; |
| 124 | } |
| 125 | |
| 126 | if (scalar->d == NULL || scalar->top == 0) { |
Kenny Root | b849459 | 2015-09-25 02:29:14 +0000 | [diff] [blame] | 127 | OPENSSL_PUT_ERROR(EC, ERR_R_INTERNAL_ERROR); |
Adam Langley | d9e397b | 2015-01-22 14:27:53 -0800 | [diff] [blame] | 128 | goto err; |
| 129 | } |
| 130 | |
| 131 | len = BN_num_bits(scalar); |
| 132 | r = OPENSSL_malloc( |
| 133 | len + |
| 134 | 1); /* modified wNAF may be one digit longer than binary representation |
| 135 | * (*ret_len will be set to the actual length, i.e. at most |
| 136 | * BN_num_bits(scalar) + 1) */ |
| 137 | if (r == NULL) { |
Kenny Root | b849459 | 2015-09-25 02:29:14 +0000 | [diff] [blame] | 138 | OPENSSL_PUT_ERROR(EC, ERR_R_MALLOC_FAILURE); |
Adam Langley | d9e397b | 2015-01-22 14:27:53 -0800 | [diff] [blame] | 139 | goto err; |
| 140 | } |
| 141 | window_val = scalar->d[0] & mask; |
| 142 | j = 0; |
| 143 | while ((window_val != 0) || |
| 144 | (j + w + 1 < len)) /* if j+w+1 >= len, window_val will not increase */ |
| 145 | { |
| 146 | int digit = 0; |
| 147 | |
| 148 | /* 0 <= window_val <= 2^(w+1) */ |
| 149 | |
| 150 | if (window_val & 1) { |
| 151 | /* 0 < window_val < 2^(w+1) */ |
| 152 | |
| 153 | if (window_val & bit) { |
| 154 | digit = window_val - next_bit; /* -2^w < digit < 0 */ |
| 155 | |
| 156 | #if 1 /* modified wNAF */ |
| 157 | if (j + w + 1 >= len) { |
| 158 | /* special case for generating modified wNAFs: |
| 159 | * no new bits will be added into window_val, |
| 160 | * so using a positive digit here will decrease |
| 161 | * the total length of the representation */ |
| 162 | |
| 163 | digit = window_val & (mask >> 1); /* 0 < digit < 2^w */ |
| 164 | } |
| 165 | #endif |
| 166 | } else { |
| 167 | digit = window_val; /* 0 < digit < 2^w */ |
| 168 | } |
| 169 | |
| 170 | if (digit <= -bit || digit >= bit || !(digit & 1)) { |
Kenny Root | b849459 | 2015-09-25 02:29:14 +0000 | [diff] [blame] | 171 | OPENSSL_PUT_ERROR(EC, ERR_R_INTERNAL_ERROR); |
Adam Langley | d9e397b | 2015-01-22 14:27:53 -0800 | [diff] [blame] | 172 | goto err; |
| 173 | } |
| 174 | |
| 175 | window_val -= digit; |
| 176 | |
| 177 | /* now window_val is 0 or 2^(w+1) in standard wNAF generation; |
| 178 | * for modified window NAFs, it may also be 2^w |
| 179 | */ |
| 180 | if (window_val != 0 && window_val != next_bit && window_val != bit) { |
Kenny Root | b849459 | 2015-09-25 02:29:14 +0000 | [diff] [blame] | 181 | OPENSSL_PUT_ERROR(EC, ERR_R_INTERNAL_ERROR); |
Adam Langley | d9e397b | 2015-01-22 14:27:53 -0800 | [diff] [blame] | 182 | goto err; |
| 183 | } |
| 184 | } |
| 185 | |
| 186 | r[j++] = sign * digit; |
| 187 | |
| 188 | window_val >>= 1; |
| 189 | window_val += bit * BN_is_bit_set(scalar, j + w); |
| 190 | |
| 191 | if (window_val > next_bit) { |
Kenny Root | b849459 | 2015-09-25 02:29:14 +0000 | [diff] [blame] | 192 | OPENSSL_PUT_ERROR(EC, ERR_R_INTERNAL_ERROR); |
Adam Langley | d9e397b | 2015-01-22 14:27:53 -0800 | [diff] [blame] | 193 | goto err; |
| 194 | } |
| 195 | } |
| 196 | |
| 197 | if (j > len + 1) { |
Kenny Root | b849459 | 2015-09-25 02:29:14 +0000 | [diff] [blame] | 198 | OPENSSL_PUT_ERROR(EC, ERR_R_INTERNAL_ERROR); |
Adam Langley | d9e397b | 2015-01-22 14:27:53 -0800 | [diff] [blame] | 199 | goto err; |
| 200 | } |
| 201 | len = j; |
| 202 | ok = 1; |
| 203 | |
| 204 | err: |
| 205 | if (!ok) { |
| 206 | OPENSSL_free(r); |
| 207 | r = NULL; |
| 208 | } |
Adam Langley | e9ada86 | 2015-05-11 17:20:37 -0700 | [diff] [blame] | 209 | if (ok) { |
Adam Langley | d9e397b | 2015-01-22 14:27:53 -0800 | [diff] [blame] | 210 | *ret_len = len; |
Adam Langley | e9ada86 | 2015-05-11 17:20:37 -0700 | [diff] [blame] | 211 | } |
Adam Langley | d9e397b | 2015-01-22 14:27:53 -0800 | [diff] [blame] | 212 | return r; |
| 213 | } |
| 214 | |
| 215 | |
| 216 | /* TODO: table should be optimised for the wNAF-based implementation, |
| 217 | * sometimes smaller windows will give better performance |
| 218 | * (thus the boundaries should be increased) |
| 219 | */ |
| 220 | #define EC_window_bits_for_scalar_size(b) \ |
| 221 | ((size_t)((b) >= 2000 ? 6 : (b) >= 800 ? 5 : (b) >= 300 \ |
| 222 | ? 4 \ |
| 223 | : (b) >= 70 ? 3 : (b) >= 20 \ |
| 224 | ? 2 \ |
| 225 | : 1)) |
| 226 | |
Adam Langley | 4139edb | 2016-01-13 15:00:54 -0800 | [diff] [blame^] | 227 | int ec_wNAF_mul(const EC_GROUP *group, EC_POINT *r, const BIGNUM *g_scalar, |
| 228 | const EC_POINT *p, const BIGNUM *p_scalar, BN_CTX *ctx) { |
Adam Langley | d9e397b | 2015-01-22 14:27:53 -0800 | [diff] [blame] | 229 | BN_CTX *new_ctx = NULL; |
| 230 | const EC_POINT *generator = NULL; |
| 231 | EC_POINT *tmp = NULL; |
Adam Langley | 4139edb | 2016-01-13 15:00:54 -0800 | [diff] [blame^] | 232 | size_t total_num; |
Adam Langley | d9e397b | 2015-01-22 14:27:53 -0800 | [diff] [blame] | 233 | size_t i, j; |
| 234 | int k; |
| 235 | int r_is_inverted = 0; |
| 236 | int r_is_at_infinity = 1; |
| 237 | size_t *wsize = NULL; /* individual window sizes */ |
| 238 | signed char **wNAF = NULL; /* individual wNAFs */ |
| 239 | size_t *wNAF_len = NULL; |
| 240 | size_t max_len = 0; |
| 241 | size_t num_val; |
| 242 | EC_POINT **val = NULL; /* precomputation */ |
| 243 | EC_POINT **v; |
Adam Langley | 4139edb | 2016-01-13 15:00:54 -0800 | [diff] [blame^] | 244 | EC_POINT ***val_sub = NULL; /* pointers to sub-arrays of 'val' */ |
Adam Langley | d9e397b | 2015-01-22 14:27:53 -0800 | [diff] [blame] | 245 | int ret = 0; |
| 246 | |
Adam Langley | d9e397b | 2015-01-22 14:27:53 -0800 | [diff] [blame] | 247 | if (ctx == NULL) { |
| 248 | ctx = new_ctx = BN_CTX_new(); |
Adam Langley | e9ada86 | 2015-05-11 17:20:37 -0700 | [diff] [blame] | 249 | if (ctx == NULL) { |
Adam Langley | d9e397b | 2015-01-22 14:27:53 -0800 | [diff] [blame] | 250 | goto err; |
Adam Langley | e9ada86 | 2015-05-11 17:20:37 -0700 | [diff] [blame] | 251 | } |
Adam Langley | d9e397b | 2015-01-22 14:27:53 -0800 | [diff] [blame] | 252 | } |
| 253 | |
Adam Langley | 4139edb | 2016-01-13 15:00:54 -0800 | [diff] [blame^] | 254 | /* TODO: This function used to take |points| and |scalars| as arrays of |
| 255 | * |num| elements. The code below should be simplified to work in terms of |p| |
| 256 | * and |p_scalar|. */ |
| 257 | size_t num = p != NULL ? 1 : 0; |
| 258 | const EC_POINT **points = p != NULL ? &p : NULL; |
| 259 | const BIGNUM **scalars = p != NULL ? &p_scalar : NULL; |
| 260 | |
| 261 | total_num = num; |
| 262 | |
| 263 | if (g_scalar != NULL) { |
Adam Langley | d9e397b | 2015-01-22 14:27:53 -0800 | [diff] [blame] | 264 | generator = EC_GROUP_get0_generator(group); |
| 265 | if (generator == NULL) { |
Kenny Root | b849459 | 2015-09-25 02:29:14 +0000 | [diff] [blame] | 266 | OPENSSL_PUT_ERROR(EC, EC_R_UNDEFINED_GENERATOR); |
Adam Langley | d9e397b | 2015-01-22 14:27:53 -0800 | [diff] [blame] | 267 | goto err; |
| 268 | } |
| 269 | |
Adam Langley | 4139edb | 2016-01-13 15:00:54 -0800 | [diff] [blame^] | 270 | ++total_num; /* treat 'g_scalar' like 'num'-th element of 'scalars' */ |
Adam Langley | d9e397b | 2015-01-22 14:27:53 -0800 | [diff] [blame] | 271 | } |
| 272 | |
Adam Langley | d9e397b | 2015-01-22 14:27:53 -0800 | [diff] [blame] | 273 | |
Adam Langley | 4139edb | 2016-01-13 15:00:54 -0800 | [diff] [blame^] | 274 | wsize = OPENSSL_malloc(total_num * sizeof wsize[0]); |
| 275 | wNAF_len = OPENSSL_malloc(total_num * sizeof wNAF_len[0]); |
| 276 | wNAF = OPENSSL_malloc((total_num + 1) * |
Adam Langley | d9e397b | 2015-01-22 14:27:53 -0800 | [diff] [blame] | 277 | sizeof wNAF[0]); /* includes space for pivot */ |
Adam Langley | 4139edb | 2016-01-13 15:00:54 -0800 | [diff] [blame^] | 278 | val_sub = OPENSSL_malloc(total_num * sizeof val_sub[0]); |
Adam Langley | d9e397b | 2015-01-22 14:27:53 -0800 | [diff] [blame] | 279 | |
| 280 | /* Ensure wNAF is initialised in case we end up going to err. */ |
| 281 | if (wNAF) { |
| 282 | wNAF[0] = NULL; /* preliminary pivot */ |
| 283 | } |
| 284 | |
| 285 | if (!wsize || !wNAF_len || !wNAF || !val_sub) { |
Kenny Root | b849459 | 2015-09-25 02:29:14 +0000 | [diff] [blame] | 286 | OPENSSL_PUT_ERROR(EC, ERR_R_MALLOC_FAILURE); |
Adam Langley | d9e397b | 2015-01-22 14:27:53 -0800 | [diff] [blame] | 287 | goto err; |
| 288 | } |
| 289 | |
| 290 | /* num_val will be the total number of temporarily precomputed points */ |
| 291 | num_val = 0; |
| 292 | |
Adam Langley | 4139edb | 2016-01-13 15:00:54 -0800 | [diff] [blame^] | 293 | for (i = 0; i < total_num; i++) { |
Adam Langley | d9e397b | 2015-01-22 14:27:53 -0800 | [diff] [blame] | 294 | size_t bits; |
| 295 | |
Adam Langley | 4139edb | 2016-01-13 15:00:54 -0800 | [diff] [blame^] | 296 | bits = i < num ? BN_num_bits(scalars[i]) : BN_num_bits(g_scalar); |
Adam Langley | d9e397b | 2015-01-22 14:27:53 -0800 | [diff] [blame] | 297 | wsize[i] = EC_window_bits_for_scalar_size(bits); |
| 298 | num_val += (size_t)1 << (wsize[i] - 1); |
| 299 | wNAF[i + 1] = NULL; /* make sure we always have a pivot */ |
| 300 | wNAF[i] = |
Adam Langley | 4139edb | 2016-01-13 15:00:54 -0800 | [diff] [blame^] | 301 | compute_wNAF((i < num ? scalars[i] : g_scalar), wsize[i], &wNAF_len[i]); |
Adam Langley | e9ada86 | 2015-05-11 17:20:37 -0700 | [diff] [blame] | 302 | if (wNAF[i] == NULL) { |
Adam Langley | d9e397b | 2015-01-22 14:27:53 -0800 | [diff] [blame] | 303 | goto err; |
Adam Langley | e9ada86 | 2015-05-11 17:20:37 -0700 | [diff] [blame] | 304 | } |
| 305 | if (wNAF_len[i] > max_len) { |
Adam Langley | d9e397b | 2015-01-22 14:27:53 -0800 | [diff] [blame] | 306 | max_len = wNAF_len[i]; |
Adam Langley | e9ada86 | 2015-05-11 17:20:37 -0700 | [diff] [blame] | 307 | } |
Adam Langley | d9e397b | 2015-01-22 14:27:53 -0800 | [diff] [blame] | 308 | } |
| 309 | |
Adam Langley | 4139edb | 2016-01-13 15:00:54 -0800 | [diff] [blame^] | 310 | /* All points we precompute now go into a single array 'val'. 'val_sub[i]' is |
| 311 | * a pointer to the subarray for the i-th point. */ |
Adam Langley | d9e397b | 2015-01-22 14:27:53 -0800 | [diff] [blame] | 312 | val = OPENSSL_malloc((num_val + 1) * sizeof val[0]); |
| 313 | if (val == NULL) { |
Kenny Root | b849459 | 2015-09-25 02:29:14 +0000 | [diff] [blame] | 314 | OPENSSL_PUT_ERROR(EC, ERR_R_MALLOC_FAILURE); |
Adam Langley | d9e397b | 2015-01-22 14:27:53 -0800 | [diff] [blame] | 315 | goto err; |
| 316 | } |
| 317 | val[num_val] = NULL; /* pivot element */ |
| 318 | |
| 319 | /* allocate points for precomputation */ |
| 320 | v = val; |
Adam Langley | 4139edb | 2016-01-13 15:00:54 -0800 | [diff] [blame^] | 321 | for (i = 0; i < total_num; i++) { |
Adam Langley | d9e397b | 2015-01-22 14:27:53 -0800 | [diff] [blame] | 322 | val_sub[i] = v; |
| 323 | for (j = 0; j < ((size_t)1 << (wsize[i] - 1)); j++) { |
| 324 | *v = EC_POINT_new(group); |
Adam Langley | e9ada86 | 2015-05-11 17:20:37 -0700 | [diff] [blame] | 325 | if (*v == NULL) { |
Adam Langley | d9e397b | 2015-01-22 14:27:53 -0800 | [diff] [blame] | 326 | goto err; |
Adam Langley | e9ada86 | 2015-05-11 17:20:37 -0700 | [diff] [blame] | 327 | } |
Adam Langley | d9e397b | 2015-01-22 14:27:53 -0800 | [diff] [blame] | 328 | v++; |
| 329 | } |
| 330 | } |
| 331 | if (!(v == val + num_val)) { |
Kenny Root | b849459 | 2015-09-25 02:29:14 +0000 | [diff] [blame] | 332 | OPENSSL_PUT_ERROR(EC, ERR_R_INTERNAL_ERROR); |
Adam Langley | d9e397b | 2015-01-22 14:27:53 -0800 | [diff] [blame] | 333 | goto err; |
| 334 | } |
| 335 | |
Adam Langley | e9ada86 | 2015-05-11 17:20:37 -0700 | [diff] [blame] | 336 | if (!(tmp = EC_POINT_new(group))) { |
Adam Langley | d9e397b | 2015-01-22 14:27:53 -0800 | [diff] [blame] | 337 | goto err; |
Adam Langley | e9ada86 | 2015-05-11 17:20:37 -0700 | [diff] [blame] | 338 | } |
Adam Langley | d9e397b | 2015-01-22 14:27:53 -0800 | [diff] [blame] | 339 | |
| 340 | /* prepare precomputed values: |
| 341 | * val_sub[i][0] := points[i] |
| 342 | * val_sub[i][1] := 3 * points[i] |
| 343 | * val_sub[i][2] := 5 * points[i] |
| 344 | * ... |
| 345 | */ |
Adam Langley | 4139edb | 2016-01-13 15:00:54 -0800 | [diff] [blame^] | 346 | for (i = 0; i < total_num; i++) { |
Adam Langley | d9e397b | 2015-01-22 14:27:53 -0800 | [diff] [blame] | 347 | if (i < num) { |
Adam Langley | e9ada86 | 2015-05-11 17:20:37 -0700 | [diff] [blame] | 348 | if (!EC_POINT_copy(val_sub[i][0], points[i])) { |
Adam Langley | d9e397b | 2015-01-22 14:27:53 -0800 | [diff] [blame] | 349 | goto err; |
Adam Langley | e9ada86 | 2015-05-11 17:20:37 -0700 | [diff] [blame] | 350 | } |
| 351 | } else if (!EC_POINT_copy(val_sub[i][0], generator)) { |
| 352 | goto err; |
Adam Langley | d9e397b | 2015-01-22 14:27:53 -0800 | [diff] [blame] | 353 | } |
| 354 | |
| 355 | if (wsize[i] > 1) { |
Adam Langley | e9ada86 | 2015-05-11 17:20:37 -0700 | [diff] [blame] | 356 | if (!EC_POINT_dbl(group, tmp, val_sub[i][0], ctx)) { |
Adam Langley | d9e397b | 2015-01-22 14:27:53 -0800 | [diff] [blame] | 357 | goto err; |
Adam Langley | e9ada86 | 2015-05-11 17:20:37 -0700 | [diff] [blame] | 358 | } |
Adam Langley | d9e397b | 2015-01-22 14:27:53 -0800 | [diff] [blame] | 359 | for (j = 1; j < ((size_t)1 << (wsize[i] - 1)); j++) { |
Adam Langley | e9ada86 | 2015-05-11 17:20:37 -0700 | [diff] [blame] | 360 | if (!EC_POINT_add(group, val_sub[i][j], val_sub[i][j - 1], tmp, ctx)) { |
Adam Langley | d9e397b | 2015-01-22 14:27:53 -0800 | [diff] [blame] | 361 | goto err; |
Adam Langley | e9ada86 | 2015-05-11 17:20:37 -0700 | [diff] [blame] | 362 | } |
Adam Langley | d9e397b | 2015-01-22 14:27:53 -0800 | [diff] [blame] | 363 | } |
| 364 | } |
| 365 | } |
| 366 | |
| 367 | #if 1 /* optional; EC_window_bits_for_scalar_size assumes we do this step */ |
Adam Langley | e9ada86 | 2015-05-11 17:20:37 -0700 | [diff] [blame] | 368 | if (!EC_POINTs_make_affine(group, num_val, val, ctx)) { |
Adam Langley | d9e397b | 2015-01-22 14:27:53 -0800 | [diff] [blame] | 369 | goto err; |
Adam Langley | e9ada86 | 2015-05-11 17:20:37 -0700 | [diff] [blame] | 370 | } |
Adam Langley | d9e397b | 2015-01-22 14:27:53 -0800 | [diff] [blame] | 371 | #endif |
| 372 | |
| 373 | r_is_at_infinity = 1; |
| 374 | |
| 375 | for (k = max_len - 1; k >= 0; k--) { |
Adam Langley | e9ada86 | 2015-05-11 17:20:37 -0700 | [diff] [blame] | 376 | if (!r_is_at_infinity && !EC_POINT_dbl(group, r, r, ctx)) { |
| 377 | goto err; |
Adam Langley | d9e397b | 2015-01-22 14:27:53 -0800 | [diff] [blame] | 378 | } |
| 379 | |
Adam Langley | 4139edb | 2016-01-13 15:00:54 -0800 | [diff] [blame^] | 380 | for (i = 0; i < total_num; i++) { |
Adam Langley | d9e397b | 2015-01-22 14:27:53 -0800 | [diff] [blame] | 381 | if (wNAF_len[i] > (size_t)k) { |
| 382 | int digit = wNAF[i][k]; |
| 383 | int is_neg; |
| 384 | |
| 385 | if (digit) { |
| 386 | is_neg = digit < 0; |
| 387 | |
Adam Langley | e9ada86 | 2015-05-11 17:20:37 -0700 | [diff] [blame] | 388 | if (is_neg) { |
Adam Langley | d9e397b | 2015-01-22 14:27:53 -0800 | [diff] [blame] | 389 | digit = -digit; |
Adam Langley | e9ada86 | 2015-05-11 17:20:37 -0700 | [diff] [blame] | 390 | } |
Adam Langley | d9e397b | 2015-01-22 14:27:53 -0800 | [diff] [blame] | 391 | |
| 392 | if (is_neg != r_is_inverted) { |
Adam Langley | e9ada86 | 2015-05-11 17:20:37 -0700 | [diff] [blame] | 393 | if (!r_is_at_infinity && !EC_POINT_invert(group, r, ctx)) { |
| 394 | goto err; |
Adam Langley | d9e397b | 2015-01-22 14:27:53 -0800 | [diff] [blame] | 395 | } |
| 396 | r_is_inverted = !r_is_inverted; |
| 397 | } |
| 398 | |
| 399 | /* digit > 0 */ |
| 400 | |
| 401 | if (r_is_at_infinity) { |
Adam Langley | e9ada86 | 2015-05-11 17:20:37 -0700 | [diff] [blame] | 402 | if (!EC_POINT_copy(r, val_sub[i][digit >> 1])) { |
Adam Langley | d9e397b | 2015-01-22 14:27:53 -0800 | [diff] [blame] | 403 | goto err; |
Adam Langley | e9ada86 | 2015-05-11 17:20:37 -0700 | [diff] [blame] | 404 | } |
Adam Langley | d9e397b | 2015-01-22 14:27:53 -0800 | [diff] [blame] | 405 | r_is_at_infinity = 0; |
| 406 | } else { |
Adam Langley | e9ada86 | 2015-05-11 17:20:37 -0700 | [diff] [blame] | 407 | if (!EC_POINT_add(group, r, r, val_sub[i][digit >> 1], ctx)) { |
Adam Langley | d9e397b | 2015-01-22 14:27:53 -0800 | [diff] [blame] | 408 | goto err; |
Adam Langley | e9ada86 | 2015-05-11 17:20:37 -0700 | [diff] [blame] | 409 | } |
Adam Langley | d9e397b | 2015-01-22 14:27:53 -0800 | [diff] [blame] | 410 | } |
| 411 | } |
| 412 | } |
| 413 | } |
| 414 | } |
| 415 | |
| 416 | if (r_is_at_infinity) { |
Adam Langley | e9ada86 | 2015-05-11 17:20:37 -0700 | [diff] [blame] | 417 | if (!EC_POINT_set_to_infinity(group, r)) { |
Adam Langley | d9e397b | 2015-01-22 14:27:53 -0800 | [diff] [blame] | 418 | goto err; |
Adam Langley | e9ada86 | 2015-05-11 17:20:37 -0700 | [diff] [blame] | 419 | } |
| 420 | } else if (r_is_inverted && !EC_POINT_invert(group, r, ctx)) { |
| 421 | goto err; |
Adam Langley | d9e397b | 2015-01-22 14:27:53 -0800 | [diff] [blame] | 422 | } |
| 423 | |
| 424 | ret = 1; |
| 425 | |
| 426 | err: |
Adam Langley | e9ada86 | 2015-05-11 17:20:37 -0700 | [diff] [blame] | 427 | BN_CTX_free(new_ctx); |
| 428 | EC_POINT_free(tmp); |
| 429 | OPENSSL_free(wsize); |
| 430 | OPENSSL_free(wNAF_len); |
Adam Langley | d9e397b | 2015-01-22 14:27:53 -0800 | [diff] [blame] | 431 | if (wNAF != NULL) { |
| 432 | signed char **w; |
| 433 | |
Adam Langley | e9ada86 | 2015-05-11 17:20:37 -0700 | [diff] [blame] | 434 | for (w = wNAF; *w != NULL; w++) { |
Adam Langley | d9e397b | 2015-01-22 14:27:53 -0800 | [diff] [blame] | 435 | OPENSSL_free(*w); |
Adam Langley | e9ada86 | 2015-05-11 17:20:37 -0700 | [diff] [blame] | 436 | } |
Adam Langley | d9e397b | 2015-01-22 14:27:53 -0800 | [diff] [blame] | 437 | |
| 438 | OPENSSL_free(wNAF); |
| 439 | } |
| 440 | if (val != NULL) { |
Adam Langley | e9ada86 | 2015-05-11 17:20:37 -0700 | [diff] [blame] | 441 | for (v = val; *v != NULL; v++) { |
Adam Langley | d9e397b | 2015-01-22 14:27:53 -0800 | [diff] [blame] | 442 | EC_POINT_clear_free(*v); |
Adam Langley | e9ada86 | 2015-05-11 17:20:37 -0700 | [diff] [blame] | 443 | } |
Adam Langley | d9e397b | 2015-01-22 14:27:53 -0800 | [diff] [blame] | 444 | |
| 445 | OPENSSL_free(val); |
| 446 | } |
Adam Langley | e9ada86 | 2015-05-11 17:20:37 -0700 | [diff] [blame] | 447 | OPENSSL_free(val_sub); |
Adam Langley | d9e397b | 2015-01-22 14:27:53 -0800 | [diff] [blame] | 448 | return ret; |
| 449 | } |