1/*
2 * Copyright 2001-2018 The OpenSSL Project Authors. All Rights Reserved.
3 * Copyright (c) 2002, Oracle and/or its affiliates. All rights reserved
4 *
5 * Licensed under the Apache License 2.0 (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
9 */
10
11#include <stdlib.h>
12
13#include <openssl/obj_mac.h>
14#include <openssl/ec.h>
15#include <openssl/bn.h>
16#include "internal/refcount.h"
17#include "crypto/ec.h"
18
19#if defined(__SUNPRO_C)
20# if __SUNPRO_C >= 0x520
21# pragma error_messages (off,E_ARRAY_OF_INCOMPLETE_NONAME,E_ARRAY_OF_INCOMPLETE)
22# endif
23#endif
24
25/* Use default functions for poin2oct, oct2point and compressed coordinates */
26#define EC_FLAGS_DEFAULT_OCT 0x1
27
28/* Use custom formats for EC_GROUP, EC_POINT and EC_KEY */
29#define EC_FLAGS_CUSTOM_CURVE 0x2
30
31/* Curve does not support signing operations */
32#define EC_FLAGS_NO_SIGN 0x4
33
34/*
35 * Structure details are not part of the exported interface, so all this may
36 * change in future versions.
37 */
38
39struct ec_method_st {
40 /* Various method flags */
41 int flags;
42 /* used by EC_METHOD_get_field_type: */
43 int field_type; /* a NID */
44 /*
45 * used by EC_GROUP_new, EC_GROUP_free, EC_GROUP_clear_free,
46 * EC_GROUP_copy:
47 */
48 int (*group_init) (EC_GROUP *);
49 void (*group_finish) (EC_GROUP *);
50 void (*group_clear_finish) (EC_GROUP *);
51 int (*group_copy) (EC_GROUP *, const EC_GROUP *);
52 /* used by EC_GROUP_set_curve, EC_GROUP_get_curve: */
53 int (*group_set_curve) (EC_GROUP *, const BIGNUM *p, const BIGNUM *a,
54 const BIGNUM *b, BN_CTX *);
55 int (*group_get_curve) (const EC_GROUP *, BIGNUM *p, BIGNUM *a, BIGNUM *b,
56 BN_CTX *);
57 /* used by EC_GROUP_get_degree: */
58 int (*group_get_degree) (const EC_GROUP *);
59 int (*group_order_bits) (const EC_GROUP *);
60 /* used by EC_GROUP_check: */
61 int (*group_check_discriminant) (const EC_GROUP *, BN_CTX *);
62 /*
63 * used by EC_POINT_new, EC_POINT_free, EC_POINT_clear_free,
64 * EC_POINT_copy:
65 */
66 int (*point_init) (EC_POINT *);
67 void (*point_finish) (EC_POINT *);
68 void (*point_clear_finish) (EC_POINT *);
69 int (*point_copy) (EC_POINT *, const EC_POINT *);
70 /*-
71 * used by EC_POINT_set_to_infinity,
72 * EC_POINT_set_Jprojective_coordinates_GFp,
73 * EC_POINT_get_Jprojective_coordinates_GFp,
74 * EC_POINT_set_affine_coordinates,
75 * EC_POINT_get_affine_coordinates,
76 * EC_POINT_set_compressed_coordinates:
77 */
78 int (*point_set_to_infinity) (const EC_GROUP *, EC_POINT *);
79 int (*point_set_Jprojective_coordinates_GFp) (const EC_GROUP *,
80 EC_POINT *, const BIGNUM *x,
81 const BIGNUM *y,
82 const BIGNUM *z, BN_CTX *);
83 int (*point_get_Jprojective_coordinates_GFp) (const EC_GROUP *,
84 const EC_POINT *, BIGNUM *x,
85 BIGNUM *y, BIGNUM *z,
86 BN_CTX *);
87 int (*point_set_affine_coordinates) (const EC_GROUP *, EC_POINT *,
88 const BIGNUM *x, const BIGNUM *y,
89 BN_CTX *);
90 int (*point_get_affine_coordinates) (const EC_GROUP *, const EC_POINT *,
91 BIGNUM *x, BIGNUM *y, BN_CTX *);
92 int (*point_set_compressed_coordinates) (const EC_GROUP *, EC_POINT *,
93 const BIGNUM *x, int y_bit,
94 BN_CTX *);
95 /* used by EC_POINT_point2oct, EC_POINT_oct2point: */
96 size_t (*point2oct) (const EC_GROUP *, const EC_POINT *,
97 point_conversion_form_t form, unsigned char *buf,
98 size_t len, BN_CTX *);
99 int (*oct2point) (const EC_GROUP *, EC_POINT *, const unsigned char *buf,
100 size_t len, BN_CTX *);
101 /* used by EC_POINT_add, EC_POINT_dbl, ECP_POINT_invert: */
102 int (*add) (const EC_GROUP *, EC_POINT *r, const EC_POINT *a,
103 const EC_POINT *b, BN_CTX *);
104 int (*dbl) (const EC_GROUP *, EC_POINT *r, const EC_POINT *a, BN_CTX *);
105 int (*invert) (const EC_GROUP *, EC_POINT *, BN_CTX *);
106 /*
107 * used by EC_POINT_is_at_infinity, EC_POINT_is_on_curve, EC_POINT_cmp:
108 */
109 int (*is_at_infinity) (const EC_GROUP *, const EC_POINT *);
110 int (*is_on_curve) (const EC_GROUP *, const EC_POINT *, BN_CTX *);
111 int (*point_cmp) (const EC_GROUP *, const EC_POINT *a, const EC_POINT *b,
112 BN_CTX *);
113 /* used by EC_POINT_make_affine, EC_POINTs_make_affine: */
114 int (*make_affine) (const EC_GROUP *, EC_POINT *, BN_CTX *);
115 int (*points_make_affine) (const EC_GROUP *, size_t num, EC_POINT *[],
116 BN_CTX *);
117 /*
118 * used by EC_POINTs_mul, EC_POINT_mul, EC_POINT_precompute_mult,
119 * EC_POINT_have_precompute_mult (default implementations are used if the
120 * 'mul' pointer is 0):
121 */
122 /*-
123 * mul() calculates the value
124 *
125 * r := generator * scalar
126 * + points[0] * scalars[0]
127 * + ...
128 * + points[num-1] * scalars[num-1].
129 *
130 * For a fixed point multiplication (scalar != NULL, num == 0)
131 * or a variable point multiplication (scalar == NULL, num == 1),
132 * mul() must use a constant time algorithm: in both cases callers
133 * should provide an input scalar (either scalar or scalars[0])
134 * in the range [0, ec_group_order); for robustness, implementers
135 * should handle the case when the scalar has not been reduced, but
136 * may treat it as an unusual input, without any constant-timeness
137 * guarantee.
138 */
139 int (*mul) (const EC_GROUP *group, EC_POINT *r, const BIGNUM *scalar,
140 size_t num, const EC_POINT *points[], const BIGNUM *scalars[],
141 BN_CTX *);
142 int (*precompute_mult) (EC_GROUP *group, BN_CTX *);
143 int (*have_precompute_mult) (const EC_GROUP *group);
144 /* internal functions */
145 /*
146 * 'field_mul', 'field_sqr', and 'field_div' can be used by 'add' and
147 * 'dbl' so that the same implementations of point operations can be used
148 * with different optimized implementations of expensive field
149 * operations:
150 */
151 int (*field_mul) (const EC_GROUP *, BIGNUM *r, const BIGNUM *a,
152 const BIGNUM *b, BN_CTX *);
153 int (*field_sqr) (const EC_GROUP *, BIGNUM *r, const BIGNUM *a, BN_CTX *);
154 int (*field_div) (const EC_GROUP *, BIGNUM *r, const BIGNUM *a,
155 const BIGNUM *b, BN_CTX *);
156 /*-
157 * 'field_inv' computes the multiplicative inverse of a in the field,
158 * storing the result in r.
159 *
160 * If 'a' is zero (or equivalent), you'll get an EC_R_CANNOT_INVERT error.
161 */
162 int (*field_inv) (const EC_GROUP *, BIGNUM *r, const BIGNUM *a, BN_CTX *);
163 /* e.g. to Montgomery */
164 int (*field_encode) (const EC_GROUP *, BIGNUM *r, const BIGNUM *a,
165 BN_CTX *);
166 /* e.g. from Montgomery */
167 int (*field_decode) (const EC_GROUP *, BIGNUM *r, const BIGNUM *a,
168 BN_CTX *);
169 int (*field_set_to_one) (const EC_GROUP *, BIGNUM *r, BN_CTX *);
170 /* private key operations */
171 size_t (*priv2oct)(const EC_KEY *eckey, unsigned char *buf, size_t len);
172 int (*oct2priv)(EC_KEY *eckey, const unsigned char *buf, size_t len);
173 int (*set_private)(EC_KEY *eckey, const BIGNUM *priv_key);
174 int (*keygen)(EC_KEY *eckey);
175 int (*keycheck)(const EC_KEY *eckey);
176 int (*keygenpub)(EC_KEY *eckey);
177 int (*keycopy)(EC_KEY *dst, const EC_KEY *src);
178 void (*keyfinish)(EC_KEY *eckey);
179 /* custom ECDH operation */
180 int (*ecdh_compute_key)(unsigned char **pout, size_t *poutlen,
181 const EC_POINT *pub_key, const EC_KEY *ecdh);
182 /* custom ECDSA */
183 int (*ecdsa_sign_setup)(EC_KEY *eckey, BN_CTX *ctx, BIGNUM **kinvp,
184 BIGNUM **rp);
185 ECDSA_SIG *(*ecdsa_sign_sig)(const unsigned char *dgst, int dgstlen,
186 const BIGNUM *kinv, const BIGNUM *r,
187 EC_KEY *eckey);
188 int (*ecdsa_verify_sig)(const unsigned char *dgst, int dgstlen,
189 const ECDSA_SIG *sig, EC_KEY *eckey);
190 /* Inverse modulo order */
191 int (*field_inverse_mod_ord)(const EC_GROUP *, BIGNUM *r,
192 const BIGNUM *x, BN_CTX *);
193 int (*blind_coordinates)(const EC_GROUP *group, EC_POINT *p, BN_CTX *ctx);
194 int (*ladder_pre)(const EC_GROUP *group,
195 EC_POINT *r, EC_POINT *s,
196 EC_POINT *p, BN_CTX *ctx);
197 int (*ladder_step)(const EC_GROUP *group,
198 EC_POINT *r, EC_POINT *s,
199 EC_POINT *p, BN_CTX *ctx);
200 int (*ladder_post)(const EC_GROUP *group,
201 EC_POINT *r, EC_POINT *s,
202 EC_POINT *p, BN_CTX *ctx);
203};
204
205/*
206 * Types and functions to manipulate pre-computed values.
207 */
208typedef struct nistp224_pre_comp_st NISTP224_PRE_COMP;
209typedef struct nistp256_pre_comp_st NISTP256_PRE_COMP;
210typedef struct nistp521_pre_comp_st NISTP521_PRE_COMP;
211typedef struct nistz256_pre_comp_st NISTZ256_PRE_COMP;
212typedef struct ec_pre_comp_st EC_PRE_COMP;
213
214struct ec_group_st {
215 const EC_METHOD *meth;
216 EC_POINT *generator; /* optional */
217 BIGNUM *order, *cofactor;
218 int curve_name; /* optional NID for named curve */
219 int asn1_flag; /* flag to control the asn1 encoding */
220 point_conversion_form_t asn1_form;
221 unsigned char *seed; /* optional seed for parameters (appears in
222 * ASN1) */
223 size_t seed_len;
224 /*
225 * The following members are handled by the method functions, even if
226 * they appear generic
227 */
228 /*
229 * Field specification. For curves over GF(p), this is the modulus; for
230 * curves over GF(2^m), this is the irreducible polynomial defining the
231 * field.
232 */
233 BIGNUM *field;
234 /*
235 * Field specification for curves over GF(2^m). The irreducible f(t) is
236 * then of the form: t^poly[0] + t^poly[1] + ... + t^poly[k] where m =
237 * poly[0] > poly[1] > ... > poly[k] = 0. The array is terminated with
238 * poly[k+1]=-1. All elliptic curve irreducibles have at most 5 non-zero
239 * terms.
240 */
241 int poly[6];
242 /*
243 * Curve coefficients. (Here the assumption is that BIGNUMs can be used
244 * or abused for all kinds of fields, not just GF(p).) For characteristic
245 * > 3, the curve is defined by a Weierstrass equation of the form y^2 =
246 * x^3 + a*x + b. For characteristic 2, the curve is defined by an
247 * equation of the form y^2 + x*y = x^3 + a*x^2 + b.
248 */
249 BIGNUM *a, *b;
250 /* enable optimized point arithmetics for special case */
251 int a_is_minus3;
252 /* method-specific (e.g., Montgomery structure) */
253 void *field_data1;
254 /* method-specific */
255 void *field_data2;
256 /* method-specific */
257 int (*field_mod_func) (BIGNUM *, const BIGNUM *, const BIGNUM *,
258 BN_CTX *);
259 /* data for ECDSA inverse */
260 BN_MONT_CTX *mont_data;
261
262 /*
263 * Precomputed values for speed. The PCT_xxx names match the
264 * pre_comp.xxx union names; see the SETPRECOMP and HAVEPRECOMP
265 * macros, below.
266 */
267 enum {
268 PCT_none,
269 PCT_nistp224, PCT_nistp256, PCT_nistp521, PCT_nistz256,
270 PCT_ec
271 } pre_comp_type;
272 union {
273 NISTP224_PRE_COMP *nistp224;
274 NISTP256_PRE_COMP *nistp256;
275 NISTP521_PRE_COMP *nistp521;
276 NISTZ256_PRE_COMP *nistz256;
277 EC_PRE_COMP *ec;
278 } pre_comp;
279
280 OPENSSL_CTX *libctx;
281};
282
283#define SETPRECOMP(g, type, pre) \
284 g->pre_comp_type = PCT_##type, g->pre_comp.type = pre
285#define HAVEPRECOMP(g, type) \
286 g->pre_comp_type == PCT_##type && g->pre_comp.type != NULL
287
288struct ec_key_st {
289 const EC_KEY_METHOD *meth;
290 ENGINE *engine;
291 int version;
292 EC_GROUP *group;
293 EC_POINT *pub_key;
294 BIGNUM *priv_key;
295 unsigned int enc_flag;
296 point_conversion_form_t conv_form;
297 CRYPTO_REF_COUNT references;
298 int flags;
299#ifndef FIPS_MODE
300 CRYPTO_EX_DATA ex_data;
301#endif
302 CRYPTO_RWLOCK *lock;
303 OPENSSL_CTX *libctx;
304};
305
306struct ec_point_st {
307 const EC_METHOD *meth;
308 /* NID for the curve if known */
309 int curve_name;
310 /*
311 * All members except 'meth' are handled by the method functions, even if
312 * they appear generic
313 */
314 BIGNUM *X;
315 BIGNUM *Y;
316 BIGNUM *Z; /* Jacobian projective coordinates: * (X, Y,
317 * Z) represents (X/Z^2, Y/Z^3) if Z != 0 */
318 int Z_is_one; /* enable optimized point arithmetics for
319 * special case */
320};
321
322static ossl_inline int ec_point_is_compat(const EC_POINT *point,
323 const EC_GROUP *group)
324{
325 return group->meth == point->meth
326 && (group->curve_name == 0
327 || point->curve_name == 0
328 || group->curve_name == point->curve_name);
329}
330
331NISTP224_PRE_COMP *EC_nistp224_pre_comp_dup(NISTP224_PRE_COMP *);
332NISTP256_PRE_COMP *EC_nistp256_pre_comp_dup(NISTP256_PRE_COMP *);
333NISTP521_PRE_COMP *EC_nistp521_pre_comp_dup(NISTP521_PRE_COMP *);
334NISTZ256_PRE_COMP *EC_nistz256_pre_comp_dup(NISTZ256_PRE_COMP *);
335NISTP256_PRE_COMP *EC_nistp256_pre_comp_dup(NISTP256_PRE_COMP *);
336EC_PRE_COMP *EC_ec_pre_comp_dup(EC_PRE_COMP *);
337
338void EC_pre_comp_free(EC_GROUP *group);
339void EC_nistp224_pre_comp_free(NISTP224_PRE_COMP *);
340void EC_nistp256_pre_comp_free(NISTP256_PRE_COMP *);
341void EC_nistp521_pre_comp_free(NISTP521_PRE_COMP *);
342void EC_nistz256_pre_comp_free(NISTZ256_PRE_COMP *);
343void EC_ec_pre_comp_free(EC_PRE_COMP *);
344
345/*
346 * method functions in ec_mult.c (ec_lib.c uses these as defaults if
347 * group->method->mul is 0)
348 */
349int ec_wNAF_mul(const EC_GROUP *group, EC_POINT *r, const BIGNUM *scalar,
350 size_t num, const EC_POINT *points[], const BIGNUM *scalars[],
351 BN_CTX *);
352int ec_wNAF_precompute_mult(EC_GROUP *group, BN_CTX *);
353int ec_wNAF_have_precompute_mult(const EC_GROUP *group);
354
355/* method functions in ecp_smpl.c */
356int ec_GFp_simple_group_init(EC_GROUP *);
357void ec_GFp_simple_group_finish(EC_GROUP *);
358void ec_GFp_simple_group_clear_finish(EC_GROUP *);
359int ec_GFp_simple_group_copy(EC_GROUP *, const EC_GROUP *);
360int ec_GFp_simple_group_set_curve(EC_GROUP *, const BIGNUM *p,
361 const BIGNUM *a, const BIGNUM *b, BN_CTX *);
362int ec_GFp_simple_group_get_curve(const EC_GROUP *, BIGNUM *p, BIGNUM *a,
363 BIGNUM *b, BN_CTX *);
364int ec_GFp_simple_group_get_degree(const EC_GROUP *);
365int ec_GFp_simple_group_check_discriminant(const EC_GROUP *, BN_CTX *);
366int ec_GFp_simple_point_init(EC_POINT *);
367void ec_GFp_simple_point_finish(EC_POINT *);
368void ec_GFp_simple_point_clear_finish(EC_POINT *);
369int ec_GFp_simple_point_copy(EC_POINT *, const EC_POINT *);
370int ec_GFp_simple_point_set_to_infinity(const EC_GROUP *, EC_POINT *);
371int ec_GFp_simple_set_Jprojective_coordinates_GFp(const EC_GROUP *,
372 EC_POINT *, const BIGNUM *x,
373 const BIGNUM *y,
374 const BIGNUM *z, BN_CTX *);
375int ec_GFp_simple_get_Jprojective_coordinates_GFp(const EC_GROUP *,
376 const EC_POINT *, BIGNUM *x,
377 BIGNUM *y, BIGNUM *z,
378 BN_CTX *);
379int ec_GFp_simple_point_set_affine_coordinates(const EC_GROUP *, EC_POINT *,
380 const BIGNUM *x,
381 const BIGNUM *y, BN_CTX *);
382int ec_GFp_simple_point_get_affine_coordinates(const EC_GROUP *,
383 const EC_POINT *, BIGNUM *x,
384 BIGNUM *y, BN_CTX *);
385int ec_GFp_simple_set_compressed_coordinates(const EC_GROUP *, EC_POINT *,
386 const BIGNUM *x, int y_bit,
387 BN_CTX *);
388size_t ec_GFp_simple_point2oct(const EC_GROUP *, const EC_POINT *,
389 point_conversion_form_t form,
390 unsigned char *buf, size_t len, BN_CTX *);
391int ec_GFp_simple_oct2point(const EC_GROUP *, EC_POINT *,
392 const unsigned char *buf, size_t len, BN_CTX *);
393int ec_GFp_simple_add(const EC_GROUP *, EC_POINT *r, const EC_POINT *a,
394 const EC_POINT *b, BN_CTX *);
395int ec_GFp_simple_dbl(const EC_GROUP *, EC_POINT *r, const EC_POINT *a,
396 BN_CTX *);
397int ec_GFp_simple_invert(const EC_GROUP *, EC_POINT *, BN_CTX *);
398int ec_GFp_simple_is_at_infinity(const EC_GROUP *, const EC_POINT *);
399int ec_GFp_simple_is_on_curve(const EC_GROUP *, const EC_POINT *, BN_CTX *);
400int ec_GFp_simple_cmp(const EC_GROUP *, const EC_POINT *a, const EC_POINT *b,
401 BN_CTX *);
402int ec_GFp_simple_make_affine(const EC_GROUP *, EC_POINT *, BN_CTX *);
403int ec_GFp_simple_points_make_affine(const EC_GROUP *, size_t num,
404 EC_POINT *[], BN_CTX *);
405int ec_GFp_simple_field_mul(const EC_GROUP *, BIGNUM *r, const BIGNUM *a,
406 const BIGNUM *b, BN_CTX *);
407int ec_GFp_simple_field_sqr(const EC_GROUP *, BIGNUM *r, const BIGNUM *a,
408 BN_CTX *);
409int ec_GFp_simple_field_inv(const EC_GROUP *, BIGNUM *r, const BIGNUM *a,
410 BN_CTX *);
411int ec_GFp_simple_blind_coordinates(const EC_GROUP *group, EC_POINT *p,
412 BN_CTX *ctx);
413int ec_GFp_simple_ladder_pre(const EC_GROUP *group,
414 EC_POINT *r, EC_POINT *s,
415 EC_POINT *p, BN_CTX *ctx);
416int ec_GFp_simple_ladder_step(const EC_GROUP *group,
417 EC_POINT *r, EC_POINT *s,
418 EC_POINT *p, BN_CTX *ctx);
419int ec_GFp_simple_ladder_post(const EC_GROUP *group,
420 EC_POINT *r, EC_POINT *s,
421 EC_POINT *p, BN_CTX *ctx);
422
423/* method functions in ecp_mont.c */
424int ec_GFp_mont_group_init(EC_GROUP *);
425int ec_GFp_mont_group_set_curve(EC_GROUP *, const BIGNUM *p, const BIGNUM *a,
426 const BIGNUM *b, BN_CTX *);
427void ec_GFp_mont_group_finish(EC_GROUP *);
428void ec_GFp_mont_group_clear_finish(EC_GROUP *);
429int ec_GFp_mont_group_copy(EC_GROUP *, const EC_GROUP *);
430int ec_GFp_mont_field_mul(const EC_GROUP *, BIGNUM *r, const BIGNUM *a,
431 const BIGNUM *b, BN_CTX *);
432int ec_GFp_mont_field_sqr(const EC_GROUP *, BIGNUM *r, const BIGNUM *a,
433 BN_CTX *);
434int ec_GFp_mont_field_inv(const EC_GROUP *, BIGNUM *r, const BIGNUM *a,
435 BN_CTX *);
436int ec_GFp_mont_field_encode(const EC_GROUP *, BIGNUM *r, const BIGNUM *a,
437 BN_CTX *);
438int ec_GFp_mont_field_decode(const EC_GROUP *, BIGNUM *r, const BIGNUM *a,
439 BN_CTX *);
440int ec_GFp_mont_field_set_to_one(const EC_GROUP *, BIGNUM *r, BN_CTX *);
441
442/* method functions in ecp_nist.c */
443int ec_GFp_nist_group_copy(EC_GROUP *dest, const EC_GROUP *src);
444int ec_GFp_nist_group_set_curve(EC_GROUP *, const BIGNUM *p, const BIGNUM *a,
445 const BIGNUM *b, BN_CTX *);
446int ec_GFp_nist_field_mul(const EC_GROUP *, BIGNUM *r, const BIGNUM *a,
447 const BIGNUM *b, BN_CTX *);
448int ec_GFp_nist_field_sqr(const EC_GROUP *, BIGNUM *r, const BIGNUM *a,
449 BN_CTX *);
450
451/* method functions in ec2_smpl.c */
452int ec_GF2m_simple_group_init(EC_GROUP *);
453void ec_GF2m_simple_group_finish(EC_GROUP *);
454void ec_GF2m_simple_group_clear_finish(EC_GROUP *);
455int ec_GF2m_simple_group_copy(EC_GROUP *, const EC_GROUP *);
456int ec_GF2m_simple_group_set_curve(EC_GROUP *, const BIGNUM *p,
457 const BIGNUM *a, const BIGNUM *b,
458 BN_CTX *);
459int ec_GF2m_simple_group_get_curve(const EC_GROUP *, BIGNUM *p, BIGNUM *a,
460 BIGNUM *b, BN_CTX *);
461int ec_GF2m_simple_group_get_degree(const EC_GROUP *);
462int ec_GF2m_simple_group_check_discriminant(const EC_GROUP *, BN_CTX *);
463int ec_GF2m_simple_point_init(EC_POINT *);
464void ec_GF2m_simple_point_finish(EC_POINT *);
465void ec_GF2m_simple_point_clear_finish(EC_POINT *);
466int ec_GF2m_simple_point_copy(EC_POINT *, const EC_POINT *);
467int ec_GF2m_simple_point_set_to_infinity(const EC_GROUP *, EC_POINT *);
468int ec_GF2m_simple_point_set_affine_coordinates(const EC_GROUP *, EC_POINT *,
469 const BIGNUM *x,
470 const BIGNUM *y, BN_CTX *);
471int ec_GF2m_simple_point_get_affine_coordinates(const EC_GROUP *,
472 const EC_POINT *, BIGNUM *x,
473 BIGNUM *y, BN_CTX *);
474int ec_GF2m_simple_set_compressed_coordinates(const EC_GROUP *, EC_POINT *,
475 const BIGNUM *x, int y_bit,
476 BN_CTX *);
477size_t ec_GF2m_simple_point2oct(const EC_GROUP *, const EC_POINT *,
478 point_conversion_form_t form,
479 unsigned char *buf, size_t len, BN_CTX *);
480int ec_GF2m_simple_oct2point(const EC_GROUP *, EC_POINT *,
481 const unsigned char *buf, size_t len, BN_CTX *);
482int ec_GF2m_simple_add(const EC_GROUP *, EC_POINT *r, const EC_POINT *a,
483 const EC_POINT *b, BN_CTX *);
484int ec_GF2m_simple_dbl(const EC_GROUP *, EC_POINT *r, const EC_POINT *a,
485 BN_CTX *);
486int ec_GF2m_simple_invert(const EC_GROUP *, EC_POINT *, BN_CTX *);
487int ec_GF2m_simple_is_at_infinity(const EC_GROUP *, const EC_POINT *);
488int ec_GF2m_simple_is_on_curve(const EC_GROUP *, const EC_POINT *, BN_CTX *);
489int ec_GF2m_simple_cmp(const EC_GROUP *, const EC_POINT *a, const EC_POINT *b,
490 BN_CTX *);
491int ec_GF2m_simple_make_affine(const EC_GROUP *, EC_POINT *, BN_CTX *);
492int ec_GF2m_simple_points_make_affine(const EC_GROUP *, size_t num,
493 EC_POINT *[], BN_CTX *);
494int ec_GF2m_simple_field_mul(const EC_GROUP *, BIGNUM *r, const BIGNUM *a,
495 const BIGNUM *b, BN_CTX *);
496int ec_GF2m_simple_field_sqr(const EC_GROUP *, BIGNUM *r, const BIGNUM *a,
497 BN_CTX *);
498int ec_GF2m_simple_field_div(const EC_GROUP *, BIGNUM *r, const BIGNUM *a,
499 const BIGNUM *b, BN_CTX *);
500
501#ifndef OPENSSL_NO_EC_NISTP_64_GCC_128
502/* method functions in ecp_nistp224.c */
503int ec_GFp_nistp224_group_init(EC_GROUP *group);
504int ec_GFp_nistp224_group_set_curve(EC_GROUP *group, const BIGNUM *p,
505 const BIGNUM *a, const BIGNUM *n,
506 BN_CTX *);
507int ec_GFp_nistp224_point_get_affine_coordinates(const EC_GROUP *group,
508 const EC_POINT *point,
509 BIGNUM *x, BIGNUM *y,
510 BN_CTX *ctx);
511int ec_GFp_nistp224_mul(const EC_GROUP *group, EC_POINT *r,
512 const BIGNUM *scalar, size_t num,
513 const EC_POINT *points[], const BIGNUM *scalars[],
514 BN_CTX *);
515int ec_GFp_nistp224_points_mul(const EC_GROUP *group, EC_POINT *r,
516 const BIGNUM *scalar, size_t num,
517 const EC_POINT *points[],
518 const BIGNUM *scalars[], BN_CTX *ctx);
519int ec_GFp_nistp224_precompute_mult(EC_GROUP *group, BN_CTX *ctx);
520int ec_GFp_nistp224_have_precompute_mult(const EC_GROUP *group);
521
522/* method functions in ecp_nistp256.c */
523int ec_GFp_nistp256_group_init(EC_GROUP *group);
524int ec_GFp_nistp256_group_set_curve(EC_GROUP *group, const BIGNUM *p,
525 const BIGNUM *a, const BIGNUM *n,
526 BN_CTX *);
527int ec_GFp_nistp256_point_get_affine_coordinates(const EC_GROUP *group,
528 const EC_POINT *point,
529 BIGNUM *x, BIGNUM *y,
530 BN_CTX *ctx);
531int ec_GFp_nistp256_mul(const EC_GROUP *group, EC_POINT *r,
532 const BIGNUM *scalar, size_t num,
533 const EC_POINT *points[], const BIGNUM *scalars[],
534 BN_CTX *);
535int ec_GFp_nistp256_points_mul(const EC_GROUP *group, EC_POINT *r,
536 const BIGNUM *scalar, size_t num,
537 const EC_POINT *points[],
538 const BIGNUM *scalars[], BN_CTX *ctx);
539int ec_GFp_nistp256_precompute_mult(EC_GROUP *group, BN_CTX *ctx);
540int ec_GFp_nistp256_have_precompute_mult(const EC_GROUP *group);
541
542/* method functions in ecp_nistp521.c */
543int ec_GFp_nistp521_group_init(EC_GROUP *group);
544int ec_GFp_nistp521_group_set_curve(EC_GROUP *group, const BIGNUM *p,
545 const BIGNUM *a, const BIGNUM *n,
546 BN_CTX *);
547int ec_GFp_nistp521_point_get_affine_coordinates(const EC_GROUP *group,
548 const EC_POINT *point,
549 BIGNUM *x, BIGNUM *y,
550 BN_CTX *ctx);
551int ec_GFp_nistp521_mul(const EC_GROUP *group, EC_POINT *r,
552 const BIGNUM *scalar, size_t num,
553 const EC_POINT *points[], const BIGNUM *scalars[],
554 BN_CTX *);
555int ec_GFp_nistp521_points_mul(const EC_GROUP *group, EC_POINT *r,
556 const BIGNUM *scalar, size_t num,
557 const EC_POINT *points[],
558 const BIGNUM *scalars[], BN_CTX *ctx);
559int ec_GFp_nistp521_precompute_mult(EC_GROUP *group, BN_CTX *ctx);
560int ec_GFp_nistp521_have_precompute_mult(const EC_GROUP *group);
561
562/* utility functions in ecp_nistputil.c */
563void ec_GFp_nistp_points_make_affine_internal(size_t num, void *point_array,
564 size_t felem_size,
565 void *tmp_felems,
566 void (*felem_one) (void *out),
567 int (*felem_is_zero) (const void
568 *in),
569 void (*felem_assign) (void *out,
570 const void
571 *in),
572 void (*felem_square) (void *out,
573 const void
574 *in),
575 void (*felem_mul) (void *out,
576 const void
577 *in1,
578 const void
579 *in2),
580 void (*felem_inv) (void *out,
581 const void
582 *in),
583 void (*felem_contract) (void
584 *out,
585 const
586 void
587 *in));
588void ec_GFp_nistp_recode_scalar_bits(unsigned char *sign,
589 unsigned char *digit, unsigned char in);
590#endif
591int ec_group_simple_order_bits(const EC_GROUP *group);
592
593#ifdef ECP_NISTZ256_ASM
594/** Returns GFp methods using montgomery multiplication, with x86-64 optimized
595 * P256. See http://eprint.iacr.org/2013/816.
596 * \return EC_METHOD object
597 */
598const EC_METHOD *EC_GFp_nistz256_method(void);
599#endif
600#ifdef S390X_EC_ASM
601const EC_METHOD *EC_GFp_s390x_nistp256_method(void);
602const EC_METHOD *EC_GFp_s390x_nistp384_method(void);
603const EC_METHOD *EC_GFp_s390x_nistp521_method(void);
604#endif
605
606size_t ec_key_simple_priv2oct(const EC_KEY *eckey,
607 unsigned char *buf, size_t len);
608int ec_key_simple_oct2priv(EC_KEY *eckey, const unsigned char *buf, size_t len);
609int ec_key_simple_generate_key(EC_KEY *eckey);
610int ec_key_simple_generate_public_key(EC_KEY *eckey);
611int ec_key_simple_check_key(const EC_KEY *eckey);
612
613int ec_curve_nid_from_params(const EC_GROUP *group, BN_CTX *ctx);
614
615/* EC_METHOD definitions */
616
617struct ec_key_method_st {
618 const char *name;
619 int32_t flags;
620 int (*init)(EC_KEY *key);
621 void (*finish)(EC_KEY *key);
622 int (*copy)(EC_KEY *dest, const EC_KEY *src);
623 int (*set_group)(EC_KEY *key, const EC_GROUP *grp);
624 int (*set_private)(EC_KEY *key, const BIGNUM *priv_key);
625 int (*set_public)(EC_KEY *key, const EC_POINT *pub_key);
626 int (*keygen)(EC_KEY *key);
627 int (*compute_key)(unsigned char **pout, size_t *poutlen,
628 const EC_POINT *pub_key, const EC_KEY *ecdh);
629 int (*sign)(int type, const unsigned char *dgst, int dlen, unsigned char
630 *sig, unsigned int *siglen, const BIGNUM *kinv,
631 const BIGNUM *r, EC_KEY *eckey);
632 int (*sign_setup)(EC_KEY *eckey, BN_CTX *ctx_in, BIGNUM **kinvp,
633 BIGNUM **rp);
634 ECDSA_SIG *(*sign_sig)(const unsigned char *dgst, int dgst_len,
635 const BIGNUM *in_kinv, const BIGNUM *in_r,
636 EC_KEY *eckey);
637
638 int (*verify)(int type, const unsigned char *dgst, int dgst_len,
639 const unsigned char *sigbuf, int sig_len, EC_KEY *eckey);
640 int (*verify_sig)(const unsigned char *dgst, int dgst_len,
641 const ECDSA_SIG *sig, EC_KEY *eckey);
642};
643
644#define EC_KEY_METHOD_DYNAMIC 1
645
646EC_KEY *ec_key_new_method_int(OPENSSL_CTX *libctx, ENGINE *engine);
647
648int ossl_ec_key_gen(EC_KEY *eckey);
649int ossl_ecdh_compute_key(unsigned char **pout, size_t *poutlen,
650 const EC_POINT *pub_key, const EC_KEY *ecdh);
651int ecdh_simple_compute_key(unsigned char **pout, size_t *poutlen,
652 const EC_POINT *pub_key, const EC_KEY *ecdh);
653
654struct ECDSA_SIG_st {
655 BIGNUM *r;
656 BIGNUM *s;
657};
658
659int ossl_ecdsa_sign_setup(EC_KEY *eckey, BN_CTX *ctx_in, BIGNUM **kinvp,
660 BIGNUM **rp);
661int ossl_ecdsa_sign(int type, const unsigned char *dgst, int dlen,
662 unsigned char *sig, unsigned int *siglen,
663 const BIGNUM *kinv, const BIGNUM *r, EC_KEY *eckey);
664ECDSA_SIG *ossl_ecdsa_sign_sig(const unsigned char *dgst, int dgst_len,
665 const BIGNUM *in_kinv, const BIGNUM *in_r,
666 EC_KEY *eckey);
667int ossl_ecdsa_verify(int type, const unsigned char *dgst, int dgst_len,
668 const unsigned char *sigbuf, int sig_len, EC_KEY *eckey);
669int ossl_ecdsa_verify_sig(const unsigned char *dgst, int dgst_len,
670 const ECDSA_SIG *sig, EC_KEY *eckey);
671int ecdsa_simple_sign_setup(EC_KEY *eckey, BN_CTX *ctx_in, BIGNUM **kinvp,
672 BIGNUM **rp);
673ECDSA_SIG *ecdsa_simple_sign_sig(const unsigned char *dgst, int dgst_len,
674 const BIGNUM *in_kinv, const BIGNUM *in_r,
675 EC_KEY *eckey);
676int ecdsa_simple_verify_sig(const unsigned char *dgst, int dgst_len,
677 const ECDSA_SIG *sig, EC_KEY *eckey);
678
679int ED25519_sign(uint8_t *out_sig, const uint8_t *message, size_t message_len,
680 const uint8_t public_key[32], const uint8_t private_key[32]);
681int ED25519_verify(const uint8_t *message, size_t message_len,
682 const uint8_t signature[64], const uint8_t public_key[32]);
683void ED25519_public_from_private(uint8_t out_public_key[32],
684 const uint8_t private_key[32]);
685
686int X25519(uint8_t out_shared_key[32], const uint8_t private_key[32],
687 const uint8_t peer_public_value[32]);
688void X25519_public_from_private(uint8_t out_public_value[32],
689 const uint8_t private_key[32]);
690
691/*-
692 * This functions computes a single point multiplication over the EC group,
693 * using, at a high level, a Montgomery ladder with conditional swaps, with
694 * various timing attack defenses.
695 *
696 * It performs either a fixed point multiplication
697 * (scalar * generator)
698 * when point is NULL, or a variable point multiplication
699 * (scalar * point)
700 * when point is not NULL.
701 *
702 * `scalar` cannot be NULL and should be in the range [0,n) otherwise all
703 * constant time bets are off (where n is the cardinality of the EC group).
704 *
705 * This function expects `group->order` and `group->cardinality` to be well
706 * defined and non-zero: it fails with an error code otherwise.
707 *
708 * NB: This says nothing about the constant-timeness of the ladder step
709 * implementation (i.e., the default implementation is based on EC_POINT_add and
710 * EC_POINT_dbl, which of course are not constant time themselves) or the
711 * underlying multiprecision arithmetic.
712 *
713 * The product is stored in `r`.
714 *
715 * This is an internal function: callers are in charge of ensuring that the
716 * input parameters `group`, `r`, `scalar` and `ctx` are not NULL.
717 *
718 * Returns 1 on success, 0 otherwise.
719 */
720int ec_scalar_mul_ladder(const EC_GROUP *group, EC_POINT *r,
721 const BIGNUM *scalar, const EC_POINT *point,
722 BN_CTX *ctx);
723
724int ec_point_blind_coordinates(const EC_GROUP *group, EC_POINT *p, BN_CTX *ctx);
725
726static ossl_inline int ec_point_ladder_pre(const EC_GROUP *group,
727 EC_POINT *r, EC_POINT *s,
728 EC_POINT *p, BN_CTX *ctx)
729{
730 if (group->meth->ladder_pre != NULL)
731 return group->meth->ladder_pre(group, r, s, p, ctx);
732
733 if (!EC_POINT_copy(s, p)
734 || !EC_POINT_dbl(group, r, s, ctx))
735 return 0;
736
737 return 1;
738}
739
740static ossl_inline int ec_point_ladder_step(const EC_GROUP *group,
741 EC_POINT *r, EC_POINT *s,
742 EC_POINT *p, BN_CTX *ctx)
743{
744 if (group->meth->ladder_step != NULL)
745 return group->meth->ladder_step(group, r, s, p, ctx);
746
747 if (!EC_POINT_add(group, s, r, s, ctx)
748 || !EC_POINT_dbl(group, r, r, ctx))
749 return 0;
750
751 return 1;
752
753}
754
755static ossl_inline int ec_point_ladder_post(const EC_GROUP *group,
756 EC_POINT *r, EC_POINT *s,
757 EC_POINT *p, BN_CTX *ctx)
758{
759 if (group->meth->ladder_post != NULL)
760 return group->meth->ladder_post(group, r, s, p, ctx);
761
762 return 1;
763}
764