ec_lcl.h revision 296465
1/* crypto/ec/ec_lcl.h */
2/*
3 * Originally written by Bodo Moeller for the OpenSSL project.
4 */
5/* ====================================================================
6 * Copyright (c) 1998-2003 The OpenSSL Project.  All rights reserved.
7 *
8 * Redistribution and use in source and binary forms, with or without
9 * modification, are permitted provided that the following conditions
10 * are met:
11 *
12 * 1. Redistributions of source code must retain the above copyright
13 *    notice, this list of conditions and the following disclaimer.
14 *
15 * 2. Redistributions in binary form must reproduce the above copyright
16 *    notice, this list of conditions and the following disclaimer in
17 *    the documentation and/or other materials provided with the
18 *    distribution.
19 *
20 * 3. All advertising materials mentioning features or use of this
21 *    software must display the following acknowledgment:
22 *    "This product includes software developed by the OpenSSL Project
23 *    for use in the OpenSSL Toolkit. (http://www.openssl.org/)"
24 *
25 * 4. The names "OpenSSL Toolkit" and "OpenSSL Project" must not be used to
26 *    endorse or promote products derived from this software without
27 *    prior written permission. For written permission, please contact
28 *    openssl-core@openssl.org.
29 *
30 * 5. Products derived from this software may not be called "OpenSSL"
31 *    nor may "OpenSSL" appear in their names without prior written
32 *    permission of the OpenSSL Project.
33 *
34 * 6. Redistributions of any form whatsoever must retain the following
35 *    acknowledgment:
36 *    "This product includes software developed by the OpenSSL Project
37 *    for use in the OpenSSL Toolkit (http://www.openssl.org/)"
38 *
39 * THIS SOFTWARE IS PROVIDED BY THE OpenSSL PROJECT ``AS IS'' AND ANY
40 * EXPRESSED OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
41 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
42 * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE OpenSSL PROJECT OR
43 * ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
44 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
45 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
46 * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
47 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
48 * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
49 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED
50 * OF THE POSSIBILITY OF SUCH DAMAGE.
51 * ====================================================================
52 *
53 * This product includes cryptographic software written by Eric Young
54 * (eay@cryptsoft.com).  This product includes software written by Tim
55 * Hudson (tjh@cryptsoft.com).
56 *
57 */
58/* ====================================================================
59 * Copyright 2002 Sun Microsystems, Inc. ALL RIGHTS RESERVED.
60 *
61 * Portions of the attached software ("Contribution") are developed by
62 * SUN MICROSYSTEMS, INC., and are contributed to the OpenSSL project.
63 *
64 * The Contribution is licensed pursuant to the OpenSSL open source
65 * license provided above.
66 *
67 * The elliptic curve binary polynomial software is originally written by
68 * Sheueling Chang Shantz and Douglas Stebila of Sun Microsystems Laboratories.
69 *
70 */
71
72#include <stdlib.h>
73
74#include <openssl/obj_mac.h>
75#include <openssl/ec.h>
76#include <openssl/bn.h>
77
78#if defined(__SUNPRO_C)
79# if __SUNPRO_C >= 0x520
80#  pragma error_messages (off,E_ARRAY_OF_INCOMPLETE_NONAME,E_ARRAY_OF_INCOMPLETE)
81# endif
82#endif
83
84/*
85 * Structure details are not part of the exported interface, so all this may
86 * change in future versions.
87 */
88
89struct ec_method_st {
90    /* used by EC_METHOD_get_field_type: */
91    int field_type;             /* a NID */
92    /*
93     * used by EC_GROUP_new, EC_GROUP_free, EC_GROUP_clear_free,
94     * EC_GROUP_copy:
95     */
96    int (*group_init) (EC_GROUP *);
97    void (*group_finish) (EC_GROUP *);
98    void (*group_clear_finish) (EC_GROUP *);
99    int (*group_copy) (EC_GROUP *, const EC_GROUP *);
100    /* used by EC_GROUP_set_curve_GFp, EC_GROUP_get_curve_GFp, */
101    /* EC_GROUP_set_curve_GF2m, and EC_GROUP_get_curve_GF2m: */
102    int (*group_set_curve) (EC_GROUP *, const BIGNUM *p, const BIGNUM *a,
103                            const BIGNUM *b, BN_CTX *);
104    int (*group_get_curve) (const EC_GROUP *, BIGNUM *p, BIGNUM *a, BIGNUM *b,
105                            BN_CTX *);
106    /* used by EC_GROUP_get_degree: */
107    int (*group_get_degree) (const EC_GROUP *);
108    /* used by EC_GROUP_check: */
109    int (*group_check_discriminant) (const EC_GROUP *, BN_CTX *);
110    /*
111     * used by EC_POINT_new, EC_POINT_free, EC_POINT_clear_free,
112     * EC_POINT_copy:
113     */
114    int (*point_init) (EC_POINT *);
115    void (*point_finish) (EC_POINT *);
116    void (*point_clear_finish) (EC_POINT *);
117    int (*point_copy) (EC_POINT *, const EC_POINT *);
118    /*-
119     * used by EC_POINT_set_to_infinity,
120     * EC_POINT_set_Jprojective_coordinates_GFp,
121     * EC_POINT_get_Jprojective_coordinates_GFp,
122     * EC_POINT_set_affine_coordinates_GFp,     ..._GF2m,
123     * EC_POINT_get_affine_coordinates_GFp,     ..._GF2m,
124     * EC_POINT_set_compressed_coordinates_GFp, ..._GF2m:
125     */
126    int (*point_set_to_infinity) (const EC_GROUP *, EC_POINT *);
127    int (*point_set_Jprojective_coordinates_GFp) (const EC_GROUP *,
128                                                  EC_POINT *, const BIGNUM *x,
129                                                  const BIGNUM *y,
130                                                  const BIGNUM *z, BN_CTX *);
131    int (*point_get_Jprojective_coordinates_GFp) (const EC_GROUP *,
132                                                  const EC_POINT *, BIGNUM *x,
133                                                  BIGNUM *y, BIGNUM *z,
134                                                  BN_CTX *);
135    int (*point_set_affine_coordinates) (const EC_GROUP *, EC_POINT *,
136                                         const BIGNUM *x, const BIGNUM *y,
137                                         BN_CTX *);
138    int (*point_get_affine_coordinates) (const EC_GROUP *, const EC_POINT *,
139                                         BIGNUM *x, BIGNUM *y, BN_CTX *);
140    int (*point_set_compressed_coordinates) (const EC_GROUP *, EC_POINT *,
141                                             const BIGNUM *x, int y_bit,
142                                             BN_CTX *);
143    /* used by EC_POINT_point2oct, EC_POINT_oct2point: */
144    size_t (*point2oct) (const EC_GROUP *, const EC_POINT *,
145                         point_conversion_form_t form, unsigned char *buf,
146                         size_t len, BN_CTX *);
147    int (*oct2point) (const EC_GROUP *, EC_POINT *, const unsigned char *buf,
148                      size_t len, BN_CTX *);
149    /* used by EC_POINT_add, EC_POINT_dbl, ECP_POINT_invert: */
150    int (*add) (const EC_GROUP *, EC_POINT *r, const EC_POINT *a,
151                const EC_POINT *b, BN_CTX *);
152    int (*dbl) (const EC_GROUP *, EC_POINT *r, const EC_POINT *a, BN_CTX *);
153    int (*invert) (const EC_GROUP *, EC_POINT *, BN_CTX *);
154    /*
155     * used by EC_POINT_is_at_infinity, EC_POINT_is_on_curve, EC_POINT_cmp:
156     */
157    int (*is_at_infinity) (const EC_GROUP *, const EC_POINT *);
158    int (*is_on_curve) (const EC_GROUP *, const EC_POINT *, BN_CTX *);
159    int (*point_cmp) (const EC_GROUP *, const EC_POINT *a, const EC_POINT *b,
160                      BN_CTX *);
161    /* used by EC_POINT_make_affine, EC_POINTs_make_affine: */
162    int (*make_affine) (const EC_GROUP *, EC_POINT *, BN_CTX *);
163    int (*points_make_affine) (const EC_GROUP *, size_t num, EC_POINT *[],
164                               BN_CTX *);
165    /*
166     * used by EC_POINTs_mul, EC_POINT_mul, EC_POINT_precompute_mult,
167     * EC_POINT_have_precompute_mult (default implementations are used if the
168     * 'mul' pointer is 0):
169     */
170    int (*mul) (const EC_GROUP *group, EC_POINT *r, const BIGNUM *scalar,
171                size_t num, const EC_POINT *points[], const BIGNUM *scalars[],
172                BN_CTX *);
173    int (*precompute_mult) (EC_GROUP *group, BN_CTX *);
174    int (*have_precompute_mult) (const EC_GROUP *group);
175    /* internal functions */
176    /*
177     * 'field_mul', 'field_sqr', and 'field_div' can be used by 'add' and
178     * 'dbl' so that the same implementations of point operations can be used
179     * with different optimized implementations of expensive field
180     * operations:
181     */
182    int (*field_mul) (const EC_GROUP *, BIGNUM *r, const BIGNUM *a,
183                      const BIGNUM *b, BN_CTX *);
184    int (*field_sqr) (const EC_GROUP *, BIGNUM *r, const BIGNUM *a, BN_CTX *);
185    int (*field_div) (const EC_GROUP *, BIGNUM *r, const BIGNUM *a,
186                      const BIGNUM *b, BN_CTX *);
187    /* e.g. to Montgomery */
188    int (*field_encode) (const EC_GROUP *, BIGNUM *r, const BIGNUM *a,
189                         BN_CTX *);
190    /* e.g. from Montgomery */
191    int (*field_decode) (const EC_GROUP *, BIGNUM *r, const BIGNUM *a,
192                         BN_CTX *);
193    int (*field_set_to_one) (const EC_GROUP *, BIGNUM *r, BN_CTX *);
194} /* EC_METHOD */ ;
195
196typedef struct ec_extra_data_st {
197    struct ec_extra_data_st *next;
198    void *data;
199    void *(*dup_func) (void *);
200    void (*free_func) (void *);
201    void (*clear_free_func) (void *);
202} EC_EXTRA_DATA;                /* used in EC_GROUP */
203
204struct ec_group_st {
205    const EC_METHOD *meth;
206    EC_POINT *generator;        /* optional */
207    BIGNUM order, cofactor;
208    int curve_name;             /* optional NID for named curve */
209    int asn1_flag;              /* flag to control the asn1 encoding */
210    point_conversion_form_t asn1_form;
211    unsigned char *seed;        /* optional seed for parameters (appears in
212                                 * ASN1) */
213    size_t seed_len;
214    EC_EXTRA_DATA *extra_data;  /* linked list */
215    /*
216     * The following members are handled by the method functions, even if
217     * they appear generic
218     */
219    /*
220     * Field specification. For curves over GF(p), this is the modulus; for
221     * curves over GF(2^m), this is the irreducible polynomial defining the
222     * field.
223     */
224    BIGNUM field;
225    /*
226     * Field specification for curves over GF(2^m). The irreducible f(t) is
227     * then of the form: t^poly[0] + t^poly[1] + ... + t^poly[k] where m =
228     * poly[0] > poly[1] > ... > poly[k] = 0.
229     */
230    unsigned int poly[5];
231    /*
232     * Curve coefficients. (Here the assumption is that BIGNUMs can be used
233     * or abused for all kinds of fields, not just GF(p).) For characteristic
234     * > 3, the curve is defined by a Weierstrass equation of the form y^2 =
235     * x^3 + a*x + b. For characteristic 2, the curve is defined by an
236     * equation of the form y^2 + x*y = x^3 + a*x^2 + b.
237     */
238    BIGNUM a, b;
239    /* enable optimized point arithmetics for special case */
240    int a_is_minus3;
241    /* method-specific (e.g., Montgomery structure) */
242    void *field_data1;
243    /* method-specific */
244    void *field_data2;
245    /* method-specific */
246    int (*field_mod_func) (BIGNUM *, const BIGNUM *, const BIGNUM *,
247                           BN_CTX *);
248} /* EC_GROUP */ ;
249
250struct ec_key_st {
251    int version;
252    EC_GROUP *group;
253    EC_POINT *pub_key;
254    BIGNUM *priv_key;
255    unsigned int enc_flag;
256    point_conversion_form_t conv_form;
257    int references;
258    EC_EXTRA_DATA *method_data;
259} /* EC_KEY */ ;
260
261/*
262 * Basically a 'mixin' for extra data, but available for EC_GROUPs/EC_KEYs
263 * only (with visibility limited to 'package' level for now). We use the
264 * function pointers as index for retrieval; this obviates global
265 * ex_data-style index tables.
266 */
267int EC_EX_DATA_set_data(EC_EXTRA_DATA **, void *data,
268                        void *(*dup_func) (void *),
269                        void (*free_func) (void *),
270                        void (*clear_free_func) (void *));
271void *EC_EX_DATA_get_data(const EC_EXTRA_DATA *, void *(*dup_func) (void *),
272                          void (*free_func) (void *),
273                          void (*clear_free_func) (void *));
274void EC_EX_DATA_free_data(EC_EXTRA_DATA **, void *(*dup_func) (void *),
275                          void (*free_func) (void *),
276                          void (*clear_free_func) (void *));
277void EC_EX_DATA_clear_free_data(EC_EXTRA_DATA **, void *(*dup_func) (void *),
278                                void (*free_func) (void *),
279                                void (*clear_free_func) (void *));
280void EC_EX_DATA_free_all_data(EC_EXTRA_DATA **);
281void EC_EX_DATA_clear_free_all_data(EC_EXTRA_DATA **);
282
283struct ec_point_st {
284    const EC_METHOD *meth;
285    /*
286     * All members except 'meth' are handled by the method functions, even if
287     * they appear generic
288     */
289    BIGNUM X;
290    BIGNUM Y;
291    BIGNUM Z;                   /* Jacobian projective coordinates: (X, Y, Z)
292                                 * represents (X/Z^2, Y/Z^3) if Z != 0 */
293    int Z_is_one;               /* enable optimized point arithmetics for
294                                 * special case */
295} /* EC_POINT */ ;
296
297/*
298 * method functions in ec_mult.c (ec_lib.c uses these as defaults if
299 * group->method->mul is 0)
300 */
301int ec_wNAF_mul(const EC_GROUP *group, EC_POINT *r, const BIGNUM *scalar,
302                size_t num, const EC_POINT *points[], const BIGNUM *scalars[],
303                BN_CTX *);
304int ec_wNAF_precompute_mult(EC_GROUP *group, BN_CTX *);
305int ec_wNAF_have_precompute_mult(const EC_GROUP *group);
306
307/* method functions in ecp_smpl.c */
308int ec_GFp_simple_group_init(EC_GROUP *);
309void ec_GFp_simple_group_finish(EC_GROUP *);
310void ec_GFp_simple_group_clear_finish(EC_GROUP *);
311int ec_GFp_simple_group_copy(EC_GROUP *, const EC_GROUP *);
312int ec_GFp_simple_group_set_curve(EC_GROUP *, const BIGNUM *p,
313                                  const BIGNUM *a, const BIGNUM *b, BN_CTX *);
314int ec_GFp_simple_group_get_curve(const EC_GROUP *, BIGNUM *p, BIGNUM *a,
315                                  BIGNUM *b, BN_CTX *);
316int ec_GFp_simple_group_get_degree(const EC_GROUP *);
317int ec_GFp_simple_group_check_discriminant(const EC_GROUP *, BN_CTX *);
318int ec_GFp_simple_point_init(EC_POINT *);
319void ec_GFp_simple_point_finish(EC_POINT *);
320void ec_GFp_simple_point_clear_finish(EC_POINT *);
321int ec_GFp_simple_point_copy(EC_POINT *, const EC_POINT *);
322int ec_GFp_simple_point_set_to_infinity(const EC_GROUP *, EC_POINT *);
323int ec_GFp_simple_set_Jprojective_coordinates_GFp(const EC_GROUP *,
324                                                  EC_POINT *, const BIGNUM *x,
325                                                  const BIGNUM *y,
326                                                  const BIGNUM *z, BN_CTX *);
327int ec_GFp_simple_get_Jprojective_coordinates_GFp(const EC_GROUP *,
328                                                  const EC_POINT *, BIGNUM *x,
329                                                  BIGNUM *y, BIGNUM *z,
330                                                  BN_CTX *);
331int ec_GFp_simple_point_set_affine_coordinates(const EC_GROUP *, EC_POINT *,
332                                               const BIGNUM *x,
333                                               const BIGNUM *y, BN_CTX *);
334int ec_GFp_simple_point_get_affine_coordinates(const EC_GROUP *,
335                                               const EC_POINT *, BIGNUM *x,
336                                               BIGNUM *y, BN_CTX *);
337int ec_GFp_simple_set_compressed_coordinates(const EC_GROUP *, EC_POINT *,
338                                             const BIGNUM *x, int y_bit,
339                                             BN_CTX *);
340size_t ec_GFp_simple_point2oct(const EC_GROUP *, const EC_POINT *,
341                               point_conversion_form_t form,
342                               unsigned char *buf, size_t len, BN_CTX *);
343int ec_GFp_simple_oct2point(const EC_GROUP *, EC_POINT *,
344                            const unsigned char *buf, size_t len, BN_CTX *);
345int ec_GFp_simple_add(const EC_GROUP *, EC_POINT *r, const EC_POINT *a,
346                      const EC_POINT *b, BN_CTX *);
347int ec_GFp_simple_dbl(const EC_GROUP *, EC_POINT *r, const EC_POINT *a,
348                      BN_CTX *);
349int ec_GFp_simple_invert(const EC_GROUP *, EC_POINT *, BN_CTX *);
350int ec_GFp_simple_is_at_infinity(const EC_GROUP *, const EC_POINT *);
351int ec_GFp_simple_is_on_curve(const EC_GROUP *, const EC_POINT *, BN_CTX *);
352int ec_GFp_simple_cmp(const EC_GROUP *, const EC_POINT *a, const EC_POINT *b,
353                      BN_CTX *);
354int ec_GFp_simple_make_affine(const EC_GROUP *, EC_POINT *, BN_CTX *);
355int ec_GFp_simple_points_make_affine(const EC_GROUP *, size_t num,
356                                     EC_POINT *[], BN_CTX *);
357int ec_GFp_simple_field_mul(const EC_GROUP *, BIGNUM *r, const BIGNUM *a,
358                            const BIGNUM *b, BN_CTX *);
359int ec_GFp_simple_field_sqr(const EC_GROUP *, BIGNUM *r, const BIGNUM *a,
360                            BN_CTX *);
361
362/* method functions in ecp_mont.c */
363int ec_GFp_mont_group_init(EC_GROUP *);
364int ec_GFp_mont_group_set_curve(EC_GROUP *, const BIGNUM *p, const BIGNUM *a,
365                                const BIGNUM *b, BN_CTX *);
366void ec_GFp_mont_group_finish(EC_GROUP *);
367void ec_GFp_mont_group_clear_finish(EC_GROUP *);
368int ec_GFp_mont_group_copy(EC_GROUP *, const EC_GROUP *);
369int ec_GFp_mont_field_mul(const EC_GROUP *, BIGNUM *r, const BIGNUM *a,
370                          const BIGNUM *b, BN_CTX *);
371int ec_GFp_mont_field_sqr(const EC_GROUP *, BIGNUM *r, const BIGNUM *a,
372                          BN_CTX *);
373int ec_GFp_mont_field_encode(const EC_GROUP *, BIGNUM *r, const BIGNUM *a,
374                             BN_CTX *);
375int ec_GFp_mont_field_decode(const EC_GROUP *, BIGNUM *r, const BIGNUM *a,
376                             BN_CTX *);
377int ec_GFp_mont_field_set_to_one(const EC_GROUP *, BIGNUM *r, BN_CTX *);
378
379/* method functions in ecp_nist.c */
380int ec_GFp_nist_group_copy(EC_GROUP *dest, const EC_GROUP *src);
381int ec_GFp_nist_group_set_curve(EC_GROUP *, const BIGNUM *p, const BIGNUM *a,
382                                const BIGNUM *b, BN_CTX *);
383int ec_GFp_nist_field_mul(const EC_GROUP *, BIGNUM *r, const BIGNUM *a,
384                          const BIGNUM *b, BN_CTX *);
385int ec_GFp_nist_field_sqr(const EC_GROUP *, BIGNUM *r, const BIGNUM *a,
386                          BN_CTX *);
387
388/* method functions in ec2_smpl.c */
389int ec_GF2m_simple_group_init(EC_GROUP *);
390void ec_GF2m_simple_group_finish(EC_GROUP *);
391void ec_GF2m_simple_group_clear_finish(EC_GROUP *);
392int ec_GF2m_simple_group_copy(EC_GROUP *, const EC_GROUP *);
393int ec_GF2m_simple_group_set_curve(EC_GROUP *, const BIGNUM *p,
394                                   const BIGNUM *a, const BIGNUM *b,
395                                   BN_CTX *);
396int ec_GF2m_simple_group_get_curve(const EC_GROUP *, BIGNUM *p, BIGNUM *a,
397                                   BIGNUM *b, BN_CTX *);
398int ec_GF2m_simple_group_get_degree(const EC_GROUP *);
399int ec_GF2m_simple_group_check_discriminant(const EC_GROUP *, BN_CTX *);
400int ec_GF2m_simple_point_init(EC_POINT *);
401void ec_GF2m_simple_point_finish(EC_POINT *);
402void ec_GF2m_simple_point_clear_finish(EC_POINT *);
403int ec_GF2m_simple_point_copy(EC_POINT *, const EC_POINT *);
404int ec_GF2m_simple_point_set_to_infinity(const EC_GROUP *, EC_POINT *);
405int ec_GF2m_simple_point_set_affine_coordinates(const EC_GROUP *, EC_POINT *,
406                                                const BIGNUM *x,
407                                                const BIGNUM *y, BN_CTX *);
408int ec_GF2m_simple_point_get_affine_coordinates(const EC_GROUP *,
409                                                const EC_POINT *, BIGNUM *x,
410                                                BIGNUM *y, BN_CTX *);
411int ec_GF2m_simple_set_compressed_coordinates(const EC_GROUP *, EC_POINT *,
412                                              const BIGNUM *x, int y_bit,
413                                              BN_CTX *);
414size_t ec_GF2m_simple_point2oct(const EC_GROUP *, const EC_POINT *,
415                                point_conversion_form_t form,
416                                unsigned char *buf, size_t len, BN_CTX *);
417int ec_GF2m_simple_oct2point(const EC_GROUP *, EC_POINT *,
418                             const unsigned char *buf, size_t len, BN_CTX *);
419int ec_GF2m_simple_add(const EC_GROUP *, EC_POINT *r, const EC_POINT *a,
420                       const EC_POINT *b, BN_CTX *);
421int ec_GF2m_simple_dbl(const EC_GROUP *, EC_POINT *r, const EC_POINT *a,
422                       BN_CTX *);
423int ec_GF2m_simple_invert(const EC_GROUP *, EC_POINT *, BN_CTX *);
424int ec_GF2m_simple_is_at_infinity(const EC_GROUP *, const EC_POINT *);
425int ec_GF2m_simple_is_on_curve(const EC_GROUP *, const EC_POINT *, BN_CTX *);
426int ec_GF2m_simple_cmp(const EC_GROUP *, const EC_POINT *a, const EC_POINT *b,
427                       BN_CTX *);
428int ec_GF2m_simple_make_affine(const EC_GROUP *, EC_POINT *, BN_CTX *);
429int ec_GF2m_simple_points_make_affine(const EC_GROUP *, size_t num,
430                                      EC_POINT *[], BN_CTX *);
431int ec_GF2m_simple_field_mul(const EC_GROUP *, BIGNUM *r, const BIGNUM *a,
432                             const BIGNUM *b, BN_CTX *);
433int ec_GF2m_simple_field_sqr(const EC_GROUP *, BIGNUM *r, const BIGNUM *a,
434                             BN_CTX *);
435int ec_GF2m_simple_field_div(const EC_GROUP *, BIGNUM *r, const BIGNUM *a,
436                             const BIGNUM *b, BN_CTX *);
437
438/* method functions in ec2_mult.c */
439int ec_GF2m_simple_mul(const EC_GROUP *group, EC_POINT *r,
440                       const BIGNUM *scalar, size_t num,
441                       const EC_POINT *points[], const BIGNUM *scalars[],
442                       BN_CTX *);
443int ec_GF2m_precompute_mult(EC_GROUP *group, BN_CTX *ctx);
444int ec_GF2m_have_precompute_mult(const EC_GROUP *group);
445