1 /*
2 * Copyright 2001-2024 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 #ifdef OPENSSL_NO_DEPRECATED_3_0
35 typedef struct ec_method_st EC_METHOD;
36 #endif
37
38 /*
39 * Structure details are not part of the exported interface, so all this may
40 * change in future versions.
41 */
42
43 struct ec_method_st {
44 /* Various method flags */
45 int flags;
46 /* used by EC_METHOD_get_field_type: */
47 int field_type; /* a NID */
48 /*
49 * used by EC_GROUP_new, EC_GROUP_free, EC_GROUP_clear_free,
50 * EC_GROUP_copy:
51 */
52 int (*group_init) (EC_GROUP *);
53 void (*group_finish) (EC_GROUP *);
54 void (*group_clear_finish) (EC_GROUP *);
55 int (*group_copy) (EC_GROUP *, const EC_GROUP *);
56 /* used by EC_GROUP_set_curve, EC_GROUP_get_curve: */
57 int (*group_set_curve) (EC_GROUP *, const BIGNUM *p, const BIGNUM *a,
58 const BIGNUM *b, BN_CTX *);
59 int (*group_get_curve) (const EC_GROUP *, BIGNUM *p, BIGNUM *a, BIGNUM *b,
60 BN_CTX *);
61 /* used by EC_GROUP_get_degree: */
62 int (*group_get_degree) (const EC_GROUP *);
63 int (*group_order_bits) (const EC_GROUP *);
64 /* used by EC_GROUP_check: */
65 int (*group_check_discriminant) (const EC_GROUP *, BN_CTX *);
66 /*
67 * used by EC_POINT_new, EC_POINT_free, EC_POINT_clear_free,
68 * EC_POINT_copy:
69 */
70 int (*point_init) (EC_POINT *);
71 void (*point_finish) (EC_POINT *);
72 void (*point_clear_finish) (EC_POINT *);
73 int (*point_copy) (EC_POINT *, const EC_POINT *);
74 /*-
75 * used by EC_POINT_set_to_infinity,
76 * EC_POINT_set_Jprojective_coordinates_GFp,
77 * EC_POINT_get_Jprojective_coordinates_GFp,
78 * EC_POINT_set_affine_coordinates,
79 * EC_POINT_get_affine_coordinates,
80 * EC_POINT_set_compressed_coordinates:
81 */
82 int (*point_set_to_infinity) (const EC_GROUP *, EC_POINT *);
83 int (*point_set_affine_coordinates) (const EC_GROUP *, EC_POINT *,
84 const BIGNUM *x, const BIGNUM *y,
85 BN_CTX *);
86 int (*point_get_affine_coordinates) (const EC_GROUP *, const EC_POINT *,
87 BIGNUM *x, BIGNUM *y, BN_CTX *);
88 int (*point_set_compressed_coordinates) (const EC_GROUP *, EC_POINT *,
89 const BIGNUM *x, int y_bit,
90 BN_CTX *);
91 /* used by EC_POINT_point2oct, EC_POINT_oct2point: */
92 size_t (*point2oct) (const EC_GROUP *, const EC_POINT *,
93 point_conversion_form_t form, unsigned char *buf,
94 size_t len, BN_CTX *);
95 int (*oct2point) (const EC_GROUP *, EC_POINT *, const unsigned char *buf,
96 size_t len, BN_CTX *);
97 /* used by EC_POINT_add, EC_POINT_dbl, ECP_POINT_invert: */
98 int (*add) (const EC_GROUP *, EC_POINT *r, const EC_POINT *a,
99 const EC_POINT *b, BN_CTX *);
100 int (*dbl) (const EC_GROUP *, EC_POINT *r, const EC_POINT *a, BN_CTX *);
101 int (*invert) (const EC_GROUP *, EC_POINT *, BN_CTX *);
102 /*
103 * used by EC_POINT_is_at_infinity, EC_POINT_is_on_curve, EC_POINT_cmp:
104 */
105 int (*is_at_infinity) (const EC_GROUP *, const EC_POINT *);
106 int (*is_on_curve) (const EC_GROUP *, const EC_POINT *, BN_CTX *);
107 int (*point_cmp) (const EC_GROUP *, const EC_POINT *a, const EC_POINT *b,
108 BN_CTX *);
109 /* used by EC_POINT_make_affine, EC_POINTs_make_affine: */
110 int (*make_affine) (const EC_GROUP *, EC_POINT *, BN_CTX *);
111 int (*points_make_affine) (const EC_GROUP *, size_t num, EC_POINT *[],
112 BN_CTX *);
113 /*
114 * used by EC_POINTs_mul, EC_POINT_mul, EC_POINT_precompute_mult,
115 * EC_POINT_have_precompute_mult (default implementations are used if the
116 * 'mul' pointer is 0):
117 */
118 /*-
119 * mul() calculates the value
120 *
121 * r := generator * scalar
122 * + points[0] * scalars[0]
123 * + ...
124 * + points[num-1] * scalars[num-1].
125 *
126 * For a fixed point multiplication (scalar != NULL, num == 0)
127 * or a variable point multiplication (scalar == NULL, num == 1),
128 * mul() must use a constant time algorithm: in both cases callers
129 * should provide an input scalar (either scalar or scalars[0])
130 * in the range [0, ec_group_order); for robustness, implementers
131 * should handle the case when the scalar has not been reduced, but
132 * may treat it as an unusual input, without any constant-timeness
133 * guarantee.
134 */
135 int (*mul) (const EC_GROUP *group, EC_POINT *r, const BIGNUM *scalar,
136 size_t num, const EC_POINT *points[], const BIGNUM *scalars[],
137 BN_CTX *);
138 int (*precompute_mult) (EC_GROUP *group, BN_CTX *);
139 int (*have_precompute_mult) (const EC_GROUP *group);
140 /* internal functions */
141 /*
142 * 'field_mul', 'field_sqr', and 'field_div' can be used by 'add' and
143 * 'dbl' so that the same implementations of point operations can be used
144 * with different optimized implementations of expensive field
145 * operations:
146 */
147 int (*field_mul) (const EC_GROUP *, BIGNUM *r, const BIGNUM *a,
148 const BIGNUM *b, BN_CTX *);
149 int (*field_sqr) (const EC_GROUP *, BIGNUM *r, const BIGNUM *a, BN_CTX *);
150 int (*field_div) (const EC_GROUP *, BIGNUM *r, const BIGNUM *a,
151 const BIGNUM *b, BN_CTX *);
152 /*-
153 * 'field_inv' computes the multiplicative inverse of a in the field,
154 * storing the result in r.
155 *
156 * If 'a' is zero (or equivalent), you'll get an EC_R_CANNOT_INVERT error.
157 */
158 int (*field_inv) (const EC_GROUP *, BIGNUM *r, const BIGNUM *a, BN_CTX *);
159 /* e.g. to Montgomery */
160 int (*field_encode) (const EC_GROUP *, BIGNUM *r, const BIGNUM *a,
161 BN_CTX *);
162 /* e.g. from Montgomery */
163 int (*field_decode) (const EC_GROUP *, BIGNUM *r, const BIGNUM *a,
164 BN_CTX *);
165 int (*field_set_to_one) (const EC_GROUP *, BIGNUM *r, BN_CTX *);
166 /* private key operations */
167 size_t (*priv2oct)(const EC_KEY *eckey, unsigned char *buf, size_t len);
168 int (*oct2priv)(EC_KEY *eckey, const unsigned char *buf, size_t len);
169 int (*set_private)(EC_KEY *eckey, const BIGNUM *priv_key);
170 int (*keygen)(EC_KEY *eckey);
171 int (*keycheck)(const EC_KEY *eckey);
172 int (*keygenpub)(EC_KEY *eckey);
173 int (*keycopy)(EC_KEY *dst, const EC_KEY *src);
174 void (*keyfinish)(EC_KEY *eckey);
175 /* custom ECDH operation */
176 int (*ecdh_compute_key)(unsigned char **pout, size_t *poutlen,
177 const EC_POINT *pub_key, const EC_KEY *ecdh);
178 /* custom ECDSA */
179 int (*ecdsa_sign_setup)(EC_KEY *eckey, BN_CTX *ctx, BIGNUM **kinvp,
180 BIGNUM **rp);
181 ECDSA_SIG *(*ecdsa_sign_sig)(const unsigned char *dgst, int dgstlen,
182 const BIGNUM *kinv, const BIGNUM *r,
183 EC_KEY *eckey);
184 int (*ecdsa_verify_sig)(const unsigned char *dgst, int dgstlen,
185 const ECDSA_SIG *sig, EC_KEY *eckey);
186 /* Inverse modulo order */
187 int (*field_inverse_mod_ord)(const EC_GROUP *, BIGNUM *r,
188 const BIGNUM *x, BN_CTX *);
189 int (*blind_coordinates)(const EC_GROUP *group, EC_POINT *p, BN_CTX *ctx);
190 int (*ladder_pre)(const EC_GROUP *group,
191 EC_POINT *r, EC_POINT *s,
192 EC_POINT *p, BN_CTX *ctx);
193 int (*ladder_step)(const EC_GROUP *group,
194 EC_POINT *r, EC_POINT *s,
195 EC_POINT *p, BN_CTX *ctx);
196 int (*ladder_post)(const EC_GROUP *group,
197 EC_POINT *r, EC_POINT *s,
198 EC_POINT *p, BN_CTX *ctx);
199 int (*group_full_init)(EC_GROUP *group, const unsigned char *data);
200 };
201
202 /*
203 * Types and functions to manipulate pre-computed values.
204 */
205 typedef struct nistp224_pre_comp_st NISTP224_PRE_COMP;
206 typedef struct nistp256_pre_comp_st NISTP256_PRE_COMP;
207 typedef struct nistp384_pre_comp_st NISTP384_PRE_COMP;
208 typedef struct nistp521_pre_comp_st NISTP521_PRE_COMP;
209 typedef struct nistz256_pre_comp_st NISTZ256_PRE_COMP;
210 typedef struct ec_pre_comp_st EC_PRE_COMP;
211
212 struct ec_group_st {
213 const EC_METHOD *meth;
214 EC_POINT *generator; /* optional */
215 BIGNUM *order, *cofactor;
216 int curve_name; /* optional NID for named curve */
217 int asn1_flag; /* flag to control the asn1 encoding */
218 int decoded_from_explicit_params; /* set if decoded from explicit
219 * curve parameters 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 arithmetic 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_nistp384, PCT_nistp521, PCT_nistz256,
270 PCT_ec
271 } pre_comp_type;
272 union {
273 NISTP224_PRE_COMP *nistp224;
274 NISTP256_PRE_COMP *nistp256;
275 NISTP384_PRE_COMP *nistp384;
276 NISTP521_PRE_COMP *nistp521;
277 NISTZ256_PRE_COMP *nistz256;
278 EC_PRE_COMP *ec;
279 } pre_comp;
280
281 OSSL_LIB_CTX *libctx;
282 char *propq;
283 };
284
285 #define SETPRECOMP(g, type, pre) \
286 g->pre_comp_type = PCT_##type, g->pre_comp.type = pre
287 #define HAVEPRECOMP(g, type) \
288 g->pre_comp_type == PCT_##type && g->pre_comp.type != NULL
289
290 struct ec_key_st {
291 const EC_KEY_METHOD *meth;
292 ENGINE *engine;
293 int version;
294 EC_GROUP *group;
295 EC_POINT *pub_key;
296 BIGNUM *priv_key;
297 unsigned int enc_flag;
298 point_conversion_form_t conv_form;
299 CRYPTO_REF_COUNT references;
300 int flags;
301 #ifndef FIPS_MODULE
302 CRYPTO_EX_DATA ex_data;
303 #endif
304 OSSL_LIB_CTX *libctx;
305 char *propq;
306
307 /* Provider data */
308 size_t dirty_cnt; /* If any key material changes, increment this */
309 };
310
311 struct ec_point_st {
312 const EC_METHOD *meth;
313 /* NID for the curve if known */
314 int curve_name;
315 /*
316 * All members except 'meth' are handled by the method functions, even if
317 * they appear generic
318 */
319 BIGNUM *X;
320 BIGNUM *Y;
321 BIGNUM *Z; /* Jacobian projective coordinates: * (X, Y,
322 * Z) represents (X/Z^2, Y/Z^3) if Z != 0 */
323 int Z_is_one; /* enable optimized point arithmetic for
324 * special case */
325 };
326
ec_point_is_compat(const EC_POINT * point,const EC_GROUP * group)327 static ossl_inline int ec_point_is_compat(const EC_POINT *point,
328 const EC_GROUP *group)
329 {
330 return group->meth == point->meth
331 && (group->curve_name == 0
332 || point->curve_name == 0
333 || group->curve_name == point->curve_name);
334 }
335
336 NISTP224_PRE_COMP *EC_nistp224_pre_comp_dup(NISTP224_PRE_COMP *);
337 NISTP256_PRE_COMP *EC_nistp256_pre_comp_dup(NISTP256_PRE_COMP *);
338 NISTP384_PRE_COMP *ossl_ec_nistp384_pre_comp_dup(NISTP384_PRE_COMP *);
339 NISTP521_PRE_COMP *EC_nistp521_pre_comp_dup(NISTP521_PRE_COMP *);
340 NISTZ256_PRE_COMP *EC_nistz256_pre_comp_dup(NISTZ256_PRE_COMP *);
341 NISTP256_PRE_COMP *EC_nistp256_pre_comp_dup(NISTP256_PRE_COMP *);
342 EC_PRE_COMP *EC_ec_pre_comp_dup(EC_PRE_COMP *);
343
344 void EC_pre_comp_free(EC_GROUP *group);
345 void EC_nistp224_pre_comp_free(NISTP224_PRE_COMP *);
346 void EC_nistp256_pre_comp_free(NISTP256_PRE_COMP *);
347 void ossl_ec_nistp384_pre_comp_free(NISTP384_PRE_COMP *);
348 void EC_nistp521_pre_comp_free(NISTP521_PRE_COMP *);
349 void EC_nistz256_pre_comp_free(NISTZ256_PRE_COMP *);
350 void EC_ec_pre_comp_free(EC_PRE_COMP *);
351
352 /*
353 * method functions in ec_mult.c (ec_lib.c uses these as defaults if
354 * group->method->mul is 0)
355 */
356 int ossl_ec_wNAF_mul(const EC_GROUP *group, EC_POINT *r, const BIGNUM *scalar,
357 size_t num, const EC_POINT *points[],
358 const BIGNUM *scalars[], BN_CTX *);
359 int ossl_ec_wNAF_precompute_mult(EC_GROUP *group, BN_CTX *);
360 int ossl_ec_wNAF_have_precompute_mult(const EC_GROUP *group);
361
362 /* method functions in ecp_smpl.c */
363 int ossl_ec_GFp_simple_group_init(EC_GROUP *);
364 void ossl_ec_GFp_simple_group_finish(EC_GROUP *);
365 void ossl_ec_GFp_simple_group_clear_finish(EC_GROUP *);
366 int ossl_ec_GFp_simple_group_copy(EC_GROUP *, const EC_GROUP *);
367 int ossl_ec_GFp_simple_group_set_curve(EC_GROUP *, const BIGNUM *p,
368 const BIGNUM *a, const BIGNUM *b,
369 BN_CTX *);
370 int ossl_ec_GFp_simple_group_get_curve(const EC_GROUP *, BIGNUM *p, BIGNUM *a,
371 BIGNUM *b, BN_CTX *);
372 int ossl_ec_GFp_simple_group_get_degree(const EC_GROUP *);
373 int ossl_ec_GFp_simple_group_check_discriminant(const EC_GROUP *, BN_CTX *);
374 int ossl_ec_GFp_simple_point_init(EC_POINT *);
375 void ossl_ec_GFp_simple_point_finish(EC_POINT *);
376 void ossl_ec_GFp_simple_point_clear_finish(EC_POINT *);
377 int ossl_ec_GFp_simple_point_copy(EC_POINT *, const EC_POINT *);
378 int ossl_ec_GFp_simple_point_set_to_infinity(const EC_GROUP *, EC_POINT *);
379 int ossl_ec_GFp_simple_set_Jprojective_coordinates_GFp(const EC_GROUP *,
380 EC_POINT *,
381 const BIGNUM *x,
382 const BIGNUM *y,
383 const BIGNUM *z,
384 BN_CTX *);
385 int ossl_ec_GFp_simple_get_Jprojective_coordinates_GFp(const EC_GROUP *,
386 const EC_POINT *,
387 BIGNUM *x,
388 BIGNUM *y, BIGNUM *z,
389 BN_CTX *);
390 int ossl_ec_GFp_simple_point_set_affine_coordinates(const EC_GROUP *, EC_POINT *,
391 const BIGNUM *x,
392 const BIGNUM *y, BN_CTX *);
393 int ossl_ec_GFp_simple_point_get_affine_coordinates(const EC_GROUP *,
394 const EC_POINT *, BIGNUM *x,
395 BIGNUM *y, BN_CTX *);
396 int ossl_ec_GFp_simple_set_compressed_coordinates(const EC_GROUP *, EC_POINT *,
397 const BIGNUM *x, int y_bit,
398 BN_CTX *);
399 size_t ossl_ec_GFp_simple_point2oct(const EC_GROUP *, const EC_POINT *,
400 point_conversion_form_t form,
401 unsigned char *buf, size_t len, BN_CTX *);
402 int ossl_ec_GFp_simple_oct2point(const EC_GROUP *, EC_POINT *,
403 const unsigned char *buf, size_t len, BN_CTX *);
404 int ossl_ec_GFp_simple_add(const EC_GROUP *, EC_POINT *r, const EC_POINT *a,
405 const EC_POINT *b, BN_CTX *);
406 int ossl_ec_GFp_simple_dbl(const EC_GROUP *, EC_POINT *r, const EC_POINT *a,
407 BN_CTX *);
408 int ossl_ec_GFp_simple_invert(const EC_GROUP *, EC_POINT *, BN_CTX *);
409 int ossl_ec_GFp_simple_is_at_infinity(const EC_GROUP *, const EC_POINT *);
410 int ossl_ec_GFp_simple_is_on_curve(const EC_GROUP *, const EC_POINT *, BN_CTX *);
411 int ossl_ec_GFp_simple_cmp(const EC_GROUP *, const EC_POINT *a,
412 const EC_POINT *b, BN_CTX *);
413 int ossl_ec_GFp_simple_make_affine(const EC_GROUP *, EC_POINT *, BN_CTX *);
414 int ossl_ec_GFp_simple_points_make_affine(const EC_GROUP *, size_t num,
415 EC_POINT *[], BN_CTX *);
416 int ossl_ec_GFp_simple_field_mul(const EC_GROUP *, BIGNUM *r, const BIGNUM *a,
417 const BIGNUM *b, BN_CTX *);
418 int ossl_ec_GFp_simple_field_sqr(const EC_GROUP *, BIGNUM *r, const BIGNUM *a,
419 BN_CTX *);
420 int ossl_ec_GFp_simple_field_inv(const EC_GROUP *, BIGNUM *r, const BIGNUM *a,
421 BN_CTX *);
422 int ossl_ec_GFp_simple_blind_coordinates(const EC_GROUP *group, EC_POINT *p,
423 BN_CTX *ctx);
424 int ossl_ec_GFp_simple_ladder_pre(const EC_GROUP *group,
425 EC_POINT *r, EC_POINT *s,
426 EC_POINT *p, BN_CTX *ctx);
427 int ossl_ec_GFp_simple_ladder_step(const EC_GROUP *group,
428 EC_POINT *r, EC_POINT *s,
429 EC_POINT *p, BN_CTX *ctx);
430 int ossl_ec_GFp_simple_ladder_post(const EC_GROUP *group,
431 EC_POINT *r, EC_POINT *s,
432 EC_POINT *p, BN_CTX *ctx);
433
434 /* method functions in ecp_mont.c */
435 int ossl_ec_GFp_mont_group_init(EC_GROUP *);
436 int ossl_ec_GFp_mont_group_set_curve(EC_GROUP *, const BIGNUM *p,
437 const BIGNUM *a,
438 const BIGNUM *b, BN_CTX *);
439 void ossl_ec_GFp_mont_group_finish(EC_GROUP *);
440 void ossl_ec_GFp_mont_group_clear_finish(EC_GROUP *);
441 int ossl_ec_GFp_mont_group_copy(EC_GROUP *, const EC_GROUP *);
442 int ossl_ec_GFp_mont_field_mul(const EC_GROUP *, BIGNUM *r, const BIGNUM *a,
443 const BIGNUM *b, BN_CTX *);
444 int ossl_ec_GFp_mont_field_sqr(const EC_GROUP *, BIGNUM *r, const BIGNUM *a,
445 BN_CTX *);
446 int ossl_ec_GFp_mont_field_inv(const EC_GROUP *, BIGNUM *r, const BIGNUM *a,
447 BN_CTX *);
448 int ossl_ec_GFp_mont_field_encode(const EC_GROUP *, BIGNUM *r, const BIGNUM *a,
449 BN_CTX *);
450 int ossl_ec_GFp_mont_field_decode(const EC_GROUP *, BIGNUM *r, const BIGNUM *a,
451 BN_CTX *);
452 int ossl_ec_GFp_mont_field_set_to_one(const EC_GROUP *, BIGNUM *r, BN_CTX *);
453
454 /* method functions in ecp_nist.c */
455 int ossl_ec_GFp_nist_group_copy(EC_GROUP *dest, const EC_GROUP *src);
456 int ossl_ec_GFp_nist_group_set_curve(EC_GROUP *, const BIGNUM *p,
457 const BIGNUM *a, const BIGNUM *b, BN_CTX *);
458 int ossl_ec_GFp_nist_field_mul(const EC_GROUP *, BIGNUM *r, const BIGNUM *a,
459 const BIGNUM *b, BN_CTX *);
460 int ossl_ec_GFp_nist_field_sqr(const EC_GROUP *, BIGNUM *r, const BIGNUM *a,
461 BN_CTX *);
462
463 /* method functions in ec2_smpl.c */
464 int ossl_ec_GF2m_simple_group_init(EC_GROUP *);
465 void ossl_ec_GF2m_simple_group_finish(EC_GROUP *);
466 void ossl_ec_GF2m_simple_group_clear_finish(EC_GROUP *);
467 int ossl_ec_GF2m_simple_group_copy(EC_GROUP *, const EC_GROUP *);
468 int ossl_ec_GF2m_simple_group_set_curve(EC_GROUP *, const BIGNUM *p,
469 const BIGNUM *a, const BIGNUM *b,
470 BN_CTX *);
471 int ossl_ec_GF2m_simple_group_get_curve(const EC_GROUP *, BIGNUM *p, BIGNUM *a,
472 BIGNUM *b, BN_CTX *);
473 int ossl_ec_GF2m_simple_group_get_degree(const EC_GROUP *);
474 int ossl_ec_GF2m_simple_group_check_discriminant(const EC_GROUP *, BN_CTX *);
475 int ossl_ec_GF2m_simple_point_init(EC_POINT *);
476 void ossl_ec_GF2m_simple_point_finish(EC_POINT *);
477 void ossl_ec_GF2m_simple_point_clear_finish(EC_POINT *);
478 int ossl_ec_GF2m_simple_point_copy(EC_POINT *, const EC_POINT *);
479 int ossl_ec_GF2m_simple_point_set_to_infinity(const EC_GROUP *, EC_POINT *);
480 int ossl_ec_GF2m_simple_point_set_affine_coordinates(const EC_GROUP *,
481 EC_POINT *,
482 const BIGNUM *x,
483 const BIGNUM *y, BN_CTX *);
484 int ossl_ec_GF2m_simple_point_get_affine_coordinates(const EC_GROUP *,
485 const EC_POINT *, BIGNUM *x,
486 BIGNUM *y, BN_CTX *);
487 int ossl_ec_GF2m_simple_set_compressed_coordinates(const EC_GROUP *, EC_POINT *,
488 const BIGNUM *x, int y_bit,
489 BN_CTX *);
490 size_t ossl_ec_GF2m_simple_point2oct(const EC_GROUP *, const EC_POINT *,
491 point_conversion_form_t form,
492 unsigned char *buf, size_t len, BN_CTX *);
493 int ossl_ec_GF2m_simple_oct2point(const EC_GROUP *, EC_POINT *,
494 const unsigned char *buf, size_t len, BN_CTX *);
495 int ossl_ec_GF2m_simple_add(const EC_GROUP *, EC_POINT *r, const EC_POINT *a,
496 const EC_POINT *b, BN_CTX *);
497 int ossl_ec_GF2m_simple_dbl(const EC_GROUP *, EC_POINT *r, const EC_POINT *a,
498 BN_CTX *);
499 int ossl_ec_GF2m_simple_invert(const EC_GROUP *, EC_POINT *, BN_CTX *);
500 int ossl_ec_GF2m_simple_is_at_infinity(const EC_GROUP *, const EC_POINT *);
501 int ossl_ec_GF2m_simple_is_on_curve(const EC_GROUP *, const EC_POINT *, BN_CTX *);
502 int ossl_ec_GF2m_simple_cmp(const EC_GROUP *, const EC_POINT *a,
503 const EC_POINT *b, BN_CTX *);
504 int ossl_ec_GF2m_simple_make_affine(const EC_GROUP *, EC_POINT *, BN_CTX *);
505 int ossl_ec_GF2m_simple_points_make_affine(const EC_GROUP *, size_t num,
506 EC_POINT *[], BN_CTX *);
507 int ossl_ec_GF2m_simple_field_mul(const EC_GROUP *, BIGNUM *r, const BIGNUM *a,
508 const BIGNUM *b, BN_CTX *);
509 int ossl_ec_GF2m_simple_field_sqr(const EC_GROUP *, BIGNUM *r, const BIGNUM *a,
510 BN_CTX *);
511 int ossl_ec_GF2m_simple_field_div(const EC_GROUP *, BIGNUM *r, const BIGNUM *a,
512 const BIGNUM *b, BN_CTX *);
513
514 #ifndef OPENSSL_NO_EC_NISTP_64_GCC_128
515 # ifdef B_ENDIAN
516 # error "Can not enable ec_nistp_64_gcc_128 on big-endian systems"
517 # endif
518
519 /* method functions in ecp_nistp224.c */
520 int ossl_ec_GFp_nistp224_group_init(EC_GROUP *group);
521 int ossl_ec_GFp_nistp224_group_set_curve(EC_GROUP *group, const BIGNUM *p,
522 const BIGNUM *a, const BIGNUM *n,
523 BN_CTX *);
524 int ossl_ec_GFp_nistp224_point_get_affine_coordinates(const EC_GROUP *group,
525 const EC_POINT *point,
526 BIGNUM *x, BIGNUM *y,
527 BN_CTX *ctx);
528 int ossl_ec_GFp_nistp224_mul(const EC_GROUP *group, EC_POINT *r,
529 const BIGNUM *scalar, size_t num,
530 const EC_POINT *points[], const BIGNUM *scalars[],
531 BN_CTX *);
532 int ossl_ec_GFp_nistp224_points_mul(const EC_GROUP *group, EC_POINT *r,
533 const BIGNUM *scalar, size_t num,
534 const EC_POINT *points[],
535 const BIGNUM *scalars[], BN_CTX *ctx);
536 int ossl_ec_GFp_nistp224_precompute_mult(EC_GROUP *group, BN_CTX *ctx);
537 int ossl_ec_GFp_nistp224_have_precompute_mult(const EC_GROUP *group);
538
539 /* method functions in ecp_nistp256.c */
540 int ossl_ec_GFp_nistp256_group_init(EC_GROUP *group);
541 int ossl_ec_GFp_nistp256_group_set_curve(EC_GROUP *group, const BIGNUM *p,
542 const BIGNUM *a, const BIGNUM *n,
543 BN_CTX *);
544 int ossl_ec_GFp_nistp256_point_get_affine_coordinates(const EC_GROUP *group,
545 const EC_POINT *point,
546 BIGNUM *x, BIGNUM *y,
547 BN_CTX *ctx);
548 int ossl_ec_GFp_nistp256_mul(const EC_GROUP *group, EC_POINT *r,
549 const BIGNUM *scalar, size_t num,
550 const EC_POINT *points[], const BIGNUM *scalars[],
551 BN_CTX *);
552 int ossl_ec_GFp_nistp256_points_mul(const EC_GROUP *group, EC_POINT *r,
553 const BIGNUM *scalar, size_t num,
554 const EC_POINT *points[],
555 const BIGNUM *scalars[], BN_CTX *ctx);
556 int ossl_ec_GFp_nistp256_precompute_mult(EC_GROUP *group, BN_CTX *ctx);
557 int ossl_ec_GFp_nistp256_have_precompute_mult(const EC_GROUP *group);
558
559 /* method functions in ecp_nistp384.c */
560 int ossl_ec_GFp_nistp384_group_init(EC_GROUP *group);
561 int ossl_ec_GFp_nistp384_group_set_curve(EC_GROUP *group, const BIGNUM *p,
562 const BIGNUM *a, const BIGNUM *n,
563 BN_CTX *);
564 int ossl_ec_GFp_nistp384_point_get_affine_coordinates(const EC_GROUP *group,
565 const EC_POINT *point,
566 BIGNUM *x, BIGNUM *y,
567 BN_CTX *ctx);
568 int ossl_ec_GFp_nistp384_mul(const EC_GROUP *group, EC_POINT *r,
569 const BIGNUM *scalar, size_t num,
570 const EC_POINT *points[], const BIGNUM *scalars[],
571 BN_CTX *);
572 int ossl_ec_GFp_nistp384_points_mul(const EC_GROUP *group, EC_POINT *r,
573 const BIGNUM *scalar, size_t num,
574 const EC_POINT *points[],
575 const BIGNUM *scalars[], BN_CTX *ctx);
576 int ossl_ec_GFp_nistp384_precompute_mult(EC_GROUP *group, BN_CTX *ctx);
577 int ossl_ec_GFp_nistp384_have_precompute_mult(const EC_GROUP *group);
578 const EC_METHOD *ossl_ec_GFp_nistp384_method(void);
579
580 /* method functions in ecp_nistp521.c */
581 int ossl_ec_GFp_nistp521_group_init(EC_GROUP *group);
582 int ossl_ec_GFp_nistp521_group_set_curve(EC_GROUP *group, const BIGNUM *p,
583 const BIGNUM *a, const BIGNUM *n,
584 BN_CTX *);
585 int ossl_ec_GFp_nistp521_point_get_affine_coordinates(const EC_GROUP *group,
586 const EC_POINT *point,
587 BIGNUM *x, BIGNUM *y,
588 BN_CTX *ctx);
589 int ossl_ec_GFp_nistp521_mul(const EC_GROUP *group, EC_POINT *r,
590 const BIGNUM *scalar, size_t num,
591 const EC_POINT *points[], const BIGNUM *scalars[],
592 BN_CTX *);
593 int ossl_ec_GFp_nistp521_points_mul(const EC_GROUP *group, EC_POINT *r,
594 const BIGNUM *scalar, size_t num,
595 const EC_POINT *points[],
596 const BIGNUM *scalars[], BN_CTX *ctx);
597 int ossl_ec_GFp_nistp521_precompute_mult(EC_GROUP *group, BN_CTX *ctx);
598 int ossl_ec_GFp_nistp521_have_precompute_mult(const EC_GROUP *group);
599
600 /* utility functions in ecp_nistputil.c */
601 void ossl_ec_GFp_nistp_points_make_affine_internal(size_t num, void *point_array,
602 size_t felem_size,
603 void *tmp_felems,
604 void (*felem_one) (void *out),
605 int (*felem_is_zero)
606 (const void *in),
607 void (*felem_assign)
608 (void *out, const void *in),
609 void (*felem_square)
610 (void *out, const void *in),
611 void (*felem_mul)
612 (void *out,
613 const void *in1,
614 const void *in2),
615 void (*felem_inv)
616 (void *out, const void *in),
617 void (*felem_contract)
618 (void *out, const void *in));
619 void ossl_ec_GFp_nistp_recode_scalar_bits(unsigned char *sign,
620 unsigned char *digit,
621 unsigned char in);
622 #endif
623 int ossl_ec_group_simple_order_bits(const EC_GROUP *group);
624
625 /**
626 * Creates a new EC_GROUP object
627 * \param libctx The associated library context or NULL for the default
628 * library context
629 * \param propq Any property query string
630 * \param meth EC_METHOD to use
631 * \return newly created EC_GROUP object or NULL in case of an error.
632 */
633 EC_GROUP *ossl_ec_group_new_ex(OSSL_LIB_CTX *libctx, const char *propq,
634 const EC_METHOD *meth);
635
636 #ifdef ECP_NISTZ256_ASM
637 /** Returns GFp methods using montgomery multiplication, with x86-64 optimized
638 * P256. See http://eprint.iacr.org/2013/816.
639 * \return EC_METHOD object
640 */
641 const EC_METHOD *EC_GFp_nistz256_method(void);
642 #endif
643 #ifdef S390X_EC_ASM
644 const EC_METHOD *EC_GFp_s390x_nistp256_method(void);
645 const EC_METHOD *EC_GFp_s390x_nistp384_method(void);
646 const EC_METHOD *EC_GFp_s390x_nistp521_method(void);
647 #endif
648
649 size_t ossl_ec_key_simple_priv2oct(const EC_KEY *eckey,
650 unsigned char *buf, size_t len);
651 int ossl_ec_key_simple_oct2priv(EC_KEY *eckey, const unsigned char *buf,
652 size_t len);
653 int ossl_ec_key_simple_generate_key(EC_KEY *eckey);
654 int ossl_ec_key_simple_generate_public_key(EC_KEY *eckey);
655 int ossl_ec_key_simple_check_key(const EC_KEY *eckey);
656
657 #ifdef ECP_SM2P256_ASM
658 /* Returns optimized methods for SM2 */
659 const EC_METHOD *EC_GFp_sm2p256_method(void);
660 #endif
661
662 int ossl_ec_curve_nid_from_params(const EC_GROUP *group, BN_CTX *ctx);
663
664 /* EC_METHOD definitions */
665
666 struct ec_key_method_st {
667 const char *name;
668 int32_t flags;
669 int (*init)(EC_KEY *key);
670 void (*finish)(EC_KEY *key);
671 int (*copy)(EC_KEY *dest, const EC_KEY *src);
672 int (*set_group)(EC_KEY *key, const EC_GROUP *grp);
673 int (*set_private)(EC_KEY *key, const BIGNUM *priv_key);
674 int (*set_public)(EC_KEY *key, const EC_POINT *pub_key);
675 int (*keygen)(EC_KEY *key);
676 int (*compute_key)(unsigned char **pout, size_t *poutlen,
677 const EC_POINT *pub_key, const EC_KEY *ecdh);
678 int (*sign)(int type, const unsigned char *dgst, int dlen, unsigned char
679 *sig, unsigned int *siglen, const BIGNUM *kinv,
680 const BIGNUM *r, EC_KEY *eckey);
681 int (*sign_setup)(EC_KEY *eckey, BN_CTX *ctx_in, BIGNUM **kinvp,
682 BIGNUM **rp);
683 ECDSA_SIG *(*sign_sig)(const unsigned char *dgst, int dgst_len,
684 const BIGNUM *in_kinv, const BIGNUM *in_r,
685 EC_KEY *eckey);
686
687 int (*verify)(int type, const unsigned char *dgst, int dgst_len,
688 const unsigned char *sigbuf, int sig_len, EC_KEY *eckey);
689 int (*verify_sig)(const unsigned char *dgst, int dgst_len,
690 const ECDSA_SIG *sig, EC_KEY *eckey);
691 };
692
693 #define EC_KEY_METHOD_DYNAMIC 1
694
695 EC_KEY *ossl_ec_key_new_method_int(OSSL_LIB_CTX *libctx, const char *propq,
696 ENGINE *engine);
697
698 int ossl_ec_key_gen(EC_KEY *eckey);
699 int ossl_ecdh_compute_key(unsigned char **pout, size_t *poutlen,
700 const EC_POINT *pub_key, const EC_KEY *ecdh);
701 int ossl_ecdh_simple_compute_key(unsigned char **pout, size_t *poutlen,
702 const EC_POINT *pub_key, const EC_KEY *ecdh);
703
704 struct ECDSA_SIG_st {
705 BIGNUM *r;
706 BIGNUM *s;
707 };
708
709 int ossl_ecdsa_sign_setup(EC_KEY *eckey, BN_CTX *ctx_in, BIGNUM **kinvp,
710 BIGNUM **rp);
711 int ossl_ecdsa_sign(int type, const unsigned char *dgst, int dlen,
712 unsigned char *sig, unsigned int *siglen,
713 const BIGNUM *kinv, const BIGNUM *r, EC_KEY *eckey);
714 ECDSA_SIG *ossl_ecdsa_sign_sig(const unsigned char *dgst, int dgst_len,
715 const BIGNUM *in_kinv, const BIGNUM *in_r,
716 EC_KEY *eckey);
717 int ossl_ecdsa_verify(int type, const unsigned char *dgst, int dgst_len,
718 const unsigned char *sigbuf, int sig_len, EC_KEY *eckey);
719 int ossl_ecdsa_verify_sig(const unsigned char *dgst, int dgst_len,
720 const ECDSA_SIG *sig, EC_KEY *eckey);
721 int ossl_ecdsa_simple_sign_setup(EC_KEY *eckey, BN_CTX *ctx_in, BIGNUM **kinvp,
722 BIGNUM **rp);
723 ECDSA_SIG *ossl_ecdsa_simple_sign_sig(const unsigned char *dgst, int dgst_len,
724 const BIGNUM *in_kinv, const BIGNUM *in_r,
725 EC_KEY *eckey);
726 int ossl_ecdsa_simple_verify_sig(const unsigned char *dgst, int dgst_len,
727 const ECDSA_SIG *sig, EC_KEY *eckey);
728
729
730 /*-
731 * This functions computes a single point multiplication over the EC group,
732 * using, at a high level, a Montgomery ladder with conditional swaps, with
733 * various timing attack defenses.
734 *
735 * It performs either a fixed point multiplication
736 * (scalar * generator)
737 * when point is NULL, or a variable point multiplication
738 * (scalar * point)
739 * when point is not NULL.
740 *
741 * `scalar` cannot be NULL and should be in the range [0,n) otherwise all
742 * constant time bets are off (where n is the cardinality of the EC group).
743 *
744 * This function expects `group->order` and `group->cardinality` to be well
745 * defined and non-zero: it fails with an error code otherwise.
746 *
747 * NB: This says nothing about the constant-timeness of the ladder step
748 * implementation (i.e., the default implementation is based on EC_POINT_add and
749 * EC_POINT_dbl, which of course are not constant time themselves) or the
750 * underlying multiprecision arithmetic.
751 *
752 * The product is stored in `r`.
753 *
754 * This is an internal function: callers are in charge of ensuring that the
755 * input parameters `group`, `r`, `scalar` and `ctx` are not NULL.
756 *
757 * Returns 1 on success, 0 otherwise.
758 */
759 int ossl_ec_scalar_mul_ladder(const EC_GROUP *group, EC_POINT *r,
760 const BIGNUM *scalar, const EC_POINT *point,
761 BN_CTX *ctx);
762
763 int ossl_ec_point_blind_coordinates(const EC_GROUP *group, EC_POINT *p,
764 BN_CTX *ctx);
765
ec_point_ladder_pre(const EC_GROUP * group,EC_POINT * r,EC_POINT * s,EC_POINT * p,BN_CTX * ctx)766 static ossl_inline int ec_point_ladder_pre(const EC_GROUP *group,
767 EC_POINT *r, EC_POINT *s,
768 EC_POINT *p, BN_CTX *ctx)
769 {
770 if (group->meth->ladder_pre != NULL)
771 return group->meth->ladder_pre(group, r, s, p, ctx);
772
773 if (!EC_POINT_copy(s, p)
774 || !EC_POINT_dbl(group, r, s, ctx))
775 return 0;
776
777 return 1;
778 }
779
ec_point_ladder_step(const EC_GROUP * group,EC_POINT * r,EC_POINT * s,EC_POINT * p,BN_CTX * ctx)780 static ossl_inline int ec_point_ladder_step(const EC_GROUP *group,
781 EC_POINT *r, EC_POINT *s,
782 EC_POINT *p, BN_CTX *ctx)
783 {
784 if (group->meth->ladder_step != NULL)
785 return group->meth->ladder_step(group, r, s, p, ctx);
786
787 if (!EC_POINT_add(group, s, r, s, ctx)
788 || !EC_POINT_dbl(group, r, r, ctx))
789 return 0;
790
791 return 1;
792
793 }
794
ec_point_ladder_post(const EC_GROUP * group,EC_POINT * r,EC_POINT * s,EC_POINT * p,BN_CTX * ctx)795 static ossl_inline int ec_point_ladder_post(const EC_GROUP *group,
796 EC_POINT *r, EC_POINT *s,
797 EC_POINT *p, BN_CTX *ctx)
798 {
799 if (group->meth->ladder_post != NULL)
800 return group->meth->ladder_post(group, r, s, p, ctx);
801
802 return 1;
803 }
804