crypto/ec/ec_local.h

   1 /*
   2  * Copyright 2001-2023 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 };
 200
 201 /*
 202  * Types and functions to manipulate pre-computed values.
 203  */
 204 typedef struct nistp224_pre_comp_st NISTP224_PRE_COMP;
 205 typedef struct nistp256_pre_comp_st NISTP256_PRE_COMP;
 206 typedef struct nistp384_pre_comp_st NISTP384_PRE_COMP;
 207 typedef struct nistp521_pre_comp_st NISTP521_PRE_COMP;
 208 typedef struct nistz256_pre_comp_st NISTZ256_PRE_COMP;
 209 typedef struct ec_pre_comp_st EC_PRE_COMP;
 210
 211 struct ec_group_st {
 212     const EC_METHOD *meth;
 213     EC_POINT *generator;        /* optional */
 214     BIGNUM *order, *cofactor;
 215     int curve_name;             /* optional NID for named curve */
 216     int asn1_flag;              /* flag to control the asn1 encoding */
 217     int decoded_from_explicit_params; /* set if decoded from explicit
 218                                        * curve parameters encoding */
 219     point_conversion_form_t asn1_form;
 220     unsigned char *seed;        /* optional seed for parameters (appears in
 221                                  * ASN1) */
 222     size_t seed_len;
 223     /*
 224      * The following members are handled by the method functions, even if
 225      * they appear generic
 226      */
 227     /*
 228      * Field specification. For curves over GF(p), this is the modulus; for
 229      * curves over GF(2^m), this is the irreducible polynomial defining the
 230      * field.
 231      */
 232     BIGNUM *field;
 233     /*
 234      * Field specification for curves over GF(2^m). The irreducible f(t) is
 235      * then of the form: t^poly[0] + t^poly[1] + ... + t^poly[k] where m =
 236      * poly[0] > poly[1] > ... > poly[k] = 0. The array is terminated with
 237      * poly[k+1]=-1. All elliptic curve irreducibles have at most 5 non-zero
 238      * terms.
 239      */
 240     int poly[6];
 241     /*
 242      * Curve coefficients. (Here the assumption is that BIGNUMs can be used
 243      * or abused for all kinds of fields, not just GF(p).) For characteristic
 244      * > 3, the curve is defined by a Weierstrass equation of the form y^2 =
 245      * x^3 + a*x + b. For characteristic 2, the curve is defined by an
 246      * equation of the form y^2 + x*y = x^3 + a*x^2 + b.
 247      */
 248     BIGNUM *a, *b;
 249     /* enable optimized point arithmetic for special case */
 250     int a_is_minus3;
 251     /* method-specific (e.g., Montgomery structure) */
 252     void *field_data1;
 253     /* method-specific */
 254     void *field_data2;
 255     /* method-specific */
 256     int (*field_mod_func) (BIGNUM *, const BIGNUM *, const BIGNUM *,
 257                            BN_CTX *);
 258     /* data for ECDSA inverse */
 259     BN_MONT_CTX *mont_data;
 260
 261     /*
 262      * Precomputed values for speed. The PCT_xxx names match the
 263      * pre_comp.xxx union names; see the SETPRECOMP and HAVEPRECOMP
 264      * macros, below.
 265      */
 266     enum {
 267         PCT_none,
 268         PCT_nistp224, PCT_nistp256, PCT_nistp384, PCT_nistp521, PCT_nistz256,
 269         PCT_ec
 270     } pre_comp_type;
 271     union {
 272         NISTP224_PRE_COMP *nistp224;
 273         NISTP256_PRE_COMP *nistp256;
 274         NISTP384_PRE_COMP *nistp384;
 275         NISTP521_PRE_COMP *nistp521;
 276         NISTZ256_PRE_COMP *nistz256;
 277         EC_PRE_COMP *ec;
 278     } pre_comp;
 279
 280     OSSL_LIB_CTX *libctx;
 281     char *propq;
 282 };
 283
 284 #define SETPRECOMP(g, type, pre) \
 285     g->pre_comp_type = PCT_##type, g->pre_comp.type = pre
 286 #define HAVEPRECOMP(g, type) \
 287     g->pre_comp_type == PCT_##type && g->pre_comp.type != NULL
 288
 289 struct ec_key_st {
 290     const EC_KEY_METHOD *meth;
 291     ENGINE *engine;
 292     int version;
 293     EC_GROUP *group;
 294     EC_POINT *pub_key;
 295     BIGNUM *priv_key;
 296     unsigned int enc_flag;
 297     point_conversion_form_t conv_form;
 298     CRYPTO_REF_COUNT references;
 299     int flags;
 300 #ifndef FIPS_MODULE
 301     CRYPTO_EX_DATA ex_data;
 302 #endif
 303     OSSL_LIB_CTX *libctx;
 304     char *propq;
 305
 306     /* Provider data */
 307     size_t dirty_cnt; /* If any key material changes, increment this */
 308 };
 309
 310 struct ec_point_st {
 311     const EC_METHOD *meth;
 312     /* NID for the curve if known */
 313     int curve_name;
 314     /*
 315      * All members except 'meth' are handled by the method functions, even if
 316      * they appear generic
 317      */
 318     BIGNUM *X;
 319     BIGNUM *Y;
 320     BIGNUM *Z;                  /* Jacobian projective coordinates: * (X, Y,
 321                                  * Z) represents (X/Z^2, Y/Z^3) if Z != 0 */
 322     int Z_is_one;               /* enable optimized point arithmetic for
 323                                  * special case */
 324 };
 325
 326 static ossl_inline int ec_point_is_compat(const EC_POINT *point,
 327                                           const EC_GROUP *group)
 328 {
 329     return group->meth == point->meth
 330            && (group->curve_name == 0
 331                || point->curve_name == 0
 332                || group->curve_name == point->curve_name);
 333 }
 334
 335 NISTP224_PRE_COMP *EC_nistp224_pre_comp_dup(NISTP224_PRE_COMP *);
 336 NISTP256_PRE_COMP *EC_nistp256_pre_comp_dup(NISTP256_PRE_COMP *);
 337 NISTP384_PRE_COMP *ossl_ec_nistp384_pre_comp_dup(NISTP384_PRE_COMP *);
 338 NISTP521_PRE_COMP *EC_nistp521_pre_comp_dup(NISTP521_PRE_COMP *);
 339 NISTZ256_PRE_COMP *EC_nistz256_pre_comp_dup(NISTZ256_PRE_COMP *);
 340 NISTP256_PRE_COMP *EC_nistp256_pre_comp_dup(NISTP256_PRE_COMP *);
 341 EC_PRE_COMP *EC_ec_pre_comp_dup(EC_PRE_COMP *);
 342
 343 void EC_pre_comp_free(EC_GROUP *group);
 344 void EC_nistp224_pre_comp_free(NISTP224_PRE_COMP *);
 345 void EC_nistp256_pre_comp_free(NISTP256_PRE_COMP *);
 346 void ossl_ec_nistp384_pre_comp_free(NISTP384_PRE_COMP *);
 347 void EC_nistp521_pre_comp_free(NISTP521_PRE_COMP *);
 348 void EC_nistz256_pre_comp_free(NISTZ256_PRE_COMP *);
 349 void EC_ec_pre_comp_free(EC_PRE_COMP *);
 350
 351 /*
 352  * method functions in ec_mult.c (ec_lib.c uses these as defaults if
 353  * group->method->mul is 0)
 354  */
 355 int ossl_ec_wNAF_mul(const EC_GROUP *group, EC_POINT *r, const BIGNUM *scalar,
 356                      size_t num, const EC_POINT *points[],
 357                      const BIGNUM *scalars[], BN_CTX *);
 358 int ossl_ec_wNAF_precompute_mult(EC_GROUP *group, BN_CTX *);
 359 int ossl_ec_wNAF_have_precompute_mult(const EC_GROUP *group);
 360
 361 /* method functions in ecp_smpl.c */
 362 int ossl_ec_GFp_simple_group_init(EC_GROUP *);
 363 void ossl_ec_GFp_simple_group_finish(EC_GROUP *);
 364 void ossl_ec_GFp_simple_group_clear_finish(EC_GROUP *);
 365 int ossl_ec_GFp_simple_group_copy(EC_GROUP *, const EC_GROUP *);
 366 int ossl_ec_GFp_simple_group_set_curve(EC_GROUP *, const BIGNUM *p,
 367                                        const BIGNUM *a, const BIGNUM *b,
 368                                        BN_CTX *);
 369 int ossl_ec_GFp_simple_group_get_curve(const EC_GROUP *, BIGNUM *p, BIGNUM *a,
 370                                        BIGNUM *b, BN_CTX *);
 371 int ossl_ec_GFp_simple_group_get_degree(const EC_GROUP *);
 372 int ossl_ec_GFp_simple_group_check_discriminant(const EC_GROUP *, BN_CTX *);
 373 int ossl_ec_GFp_simple_point_init(EC_POINT *);
 374 void ossl_ec_GFp_simple_point_finish(EC_POINT *);
 375 void ossl_ec_GFp_simple_point_clear_finish(EC_POINT *);
 376 int ossl_ec_GFp_simple_point_copy(EC_POINT *, const EC_POINT *);
 377 int ossl_ec_GFp_simple_point_set_to_infinity(const EC_GROUP *, EC_POINT *);
 378 int ossl_ec_GFp_simple_set_Jprojective_coordinates_GFp(const EC_GROUP *,
 379                                                        EC_POINT *,
 380                                                        const BIGNUM *x,
 381                                                        const BIGNUM *y,
 382                                                        const BIGNUM *z,
 383                                                        BN_CTX *);
 384 int ossl_ec_GFp_simple_get_Jprojective_coordinates_GFp(const EC_GROUP *,
 385                                                        const EC_POINT *,
 386                                                        BIGNUM *x,
 387                                                        BIGNUM *y, BIGNUM *z,
 388                                                        BN_CTX *);
 389 int ossl_ec_GFp_simple_point_set_affine_coordinates(const EC_GROUP *, EC_POINT *,
 390                                                     const BIGNUM *x,
 391                                                     const BIGNUM *y, BN_CTX *);
 392 int ossl_ec_GFp_simple_point_get_affine_coordinates(const EC_GROUP *,
 393                                                     const EC_POINT *, BIGNUM *x,
 394                                                     BIGNUM *y, BN_CTX *);
 395 int ossl_ec_GFp_simple_set_compressed_coordinates(const EC_GROUP *, EC_POINT *,
 396                                                   const BIGNUM *x, int y_bit,
 397                                                   BN_CTX *);
 398 size_t ossl_ec_GFp_simple_point2oct(const EC_GROUP *, const EC_POINT *,
 399                                     point_conversion_form_t form,
 400                                     unsigned char *buf, size_t len, BN_CTX *);
 401 int ossl_ec_GFp_simple_oct2point(const EC_GROUP *, EC_POINT *,
 402                                  const unsigned char *buf, size_t len, BN_CTX *);
 403 int ossl_ec_GFp_simple_add(const EC_GROUP *, EC_POINT *r, const EC_POINT *a,
 404                            const EC_POINT *b, BN_CTX *);
 405 int ossl_ec_GFp_simple_dbl(const EC_GROUP *, EC_POINT *r, const EC_POINT *a,
 406                            BN_CTX *);
 407 int ossl_ec_GFp_simple_invert(const EC_GROUP *, EC_POINT *, BN_CTX *);
 408 int ossl_ec_GFp_simple_is_at_infinity(const EC_GROUP *, const EC_POINT *);
 409 int ossl_ec_GFp_simple_is_on_curve(const EC_GROUP *, const EC_POINT *, BN_CTX *);
 410 int ossl_ec_GFp_simple_cmp(const EC_GROUP *, const EC_POINT *a,
 411                            const EC_POINT *b, BN_CTX *);
 412 int ossl_ec_GFp_simple_make_affine(const EC_GROUP *, EC_POINT *, BN_CTX *);
 413 int ossl_ec_GFp_simple_points_make_affine(const EC_GROUP *, size_t num,
 414                                           EC_POINT *[], BN_CTX *);
 415 int ossl_ec_GFp_simple_field_mul(const EC_GROUP *, BIGNUM *r, const BIGNUM *a,
 416                                  const BIGNUM *b, BN_CTX *);
 417 int ossl_ec_GFp_simple_field_sqr(const EC_GROUP *, BIGNUM *r, const BIGNUM *a,
 418                                  BN_CTX *);
 419 int ossl_ec_GFp_simple_field_inv(const EC_GROUP *, BIGNUM *r, const BIGNUM *a,
 420                                  BN_CTX *);
 421 int ossl_ec_GFp_simple_blind_coordinates(const EC_GROUP *group, EC_POINT *p,
 422                                          BN_CTX *ctx);
 423 int ossl_ec_GFp_simple_ladder_pre(const EC_GROUP *group,
 424                                   EC_POINT *r, EC_POINT *s,
 425                                   EC_POINT *p, BN_CTX *ctx);
 426 int ossl_ec_GFp_simple_ladder_step(const EC_GROUP *group,
 427                                    EC_POINT *r, EC_POINT *s,
 428                                    EC_POINT *p, BN_CTX *ctx);
 429 int ossl_ec_GFp_simple_ladder_post(const EC_GROUP *group,
 430                                    EC_POINT *r, EC_POINT *s,
 431                                    EC_POINT *p, BN_CTX *ctx);
 432
 433 /* method functions in ecp_mont.c */
 434 int ossl_ec_GFp_mont_group_init(EC_GROUP *);
 435 int ossl_ec_GFp_mont_group_set_curve(EC_GROUP *, const BIGNUM *p,
 436                                      const BIGNUM *a,
 437                                      const BIGNUM *b, BN_CTX *);
 438 void ossl_ec_GFp_mont_group_finish(EC_GROUP *);
 439 void ossl_ec_GFp_mont_group_clear_finish(EC_GROUP *);
 440 int ossl_ec_GFp_mont_group_copy(EC_GROUP *, const EC_GROUP *);
 441 int ossl_ec_GFp_mont_field_mul(const EC_GROUP *, BIGNUM *r, const BIGNUM *a,
 442                                const BIGNUM *b, BN_CTX *);
 443 int ossl_ec_GFp_mont_field_sqr(const EC_GROUP *, BIGNUM *r, const BIGNUM *a,
 444                                BN_CTX *);
 445 int ossl_ec_GFp_mont_field_inv(const EC_GROUP *, BIGNUM *r, const BIGNUM *a,
 446                                BN_CTX *);
 447 int ossl_ec_GFp_mont_field_encode(const EC_GROUP *, BIGNUM *r, const BIGNUM *a,
 448                                   BN_CTX *);
 449 int ossl_ec_GFp_mont_field_decode(const EC_GROUP *, BIGNUM *r, const BIGNUM *a,
 450                                   BN_CTX *);
 451 int ossl_ec_GFp_mont_field_set_to_one(const EC_GROUP *, BIGNUM *r, BN_CTX *);
 452
 453 /* method functions in ecp_nist.c */
 454 int ossl_ec_GFp_nist_group_copy(EC_GROUP *dest, const EC_GROUP *src);
 455 int ossl_ec_GFp_nist_group_set_curve(EC_GROUP *, const BIGNUM *p,
 456                                      const BIGNUM *a, const BIGNUM *b, BN_CTX *);
 457 int ossl_ec_GFp_nist_field_mul(const EC_GROUP *, BIGNUM *r, const BIGNUM *a,
 458                               const BIGNUM *b, BN_CTX *);
 459 int ossl_ec_GFp_nist_field_sqr(const EC_GROUP *, BIGNUM *r, const BIGNUM *a,
 460                                BN_CTX *);
 461
 462 /* method functions in ec2_smpl.c */
 463 int ossl_ec_GF2m_simple_group_init(EC_GROUP *);
 464 void ossl_ec_GF2m_simple_group_finish(EC_GROUP *);
 465 void ossl_ec_GF2m_simple_group_clear_finish(EC_GROUP *);
 466 int ossl_ec_GF2m_simple_group_copy(EC_GROUP *, const EC_GROUP *);
 467 int ossl_ec_GF2m_simple_group_set_curve(EC_GROUP *, const BIGNUM *p,
 468                                         const BIGNUM *a, const BIGNUM *b,
 469                                         BN_CTX *);
 470 int ossl_ec_GF2m_simple_group_get_curve(const EC_GROUP *, BIGNUM *p, BIGNUM *a,
 471                                         BIGNUM *b, BN_CTX *);
 472 int ossl_ec_GF2m_simple_group_get_degree(const EC_GROUP *);
 473 int ossl_ec_GF2m_simple_group_check_discriminant(const EC_GROUP *, BN_CTX *);
 474 int ossl_ec_GF2m_simple_point_init(EC_POINT *);
 475 void ossl_ec_GF2m_simple_point_finish(EC_POINT *);
 476 void ossl_ec_GF2m_simple_point_clear_finish(EC_POINT *);
 477 int ossl_ec_GF2m_simple_point_copy(EC_POINT *, const EC_POINT *);
 478 int ossl_ec_GF2m_simple_point_set_to_infinity(const EC_GROUP *, EC_POINT *);
 479 int ossl_ec_GF2m_simple_point_set_affine_coordinates(const EC_GROUP *,
 480                                                      EC_POINT *,
 481                                                      const BIGNUM *x,
 482                                                      const BIGNUM *y, BN_CTX *);
 483 int ossl_ec_GF2m_simple_point_get_affine_coordinates(const EC_GROUP *,
 484                                                      const EC_POINT *, BIGNUM *x,
 485                                                      BIGNUM *y, BN_CTX *);
 486 int ossl_ec_GF2m_simple_set_compressed_coordinates(const EC_GROUP *, EC_POINT *,
 487                                                    const BIGNUM *x, int y_bit,
 488                                                    BN_CTX *);
 489 size_t ossl_ec_GF2m_simple_point2oct(const EC_GROUP *, const EC_POINT *,
 490                                      point_conversion_form_t form,
 491                                      unsigned char *buf, size_t len, BN_CTX *);
 492 int ossl_ec_GF2m_simple_oct2point(const EC_GROUP *, EC_POINT *,
 493                                   const unsigned char *buf, size_t len, BN_CTX *);
 494 int ossl_ec_GF2m_simple_add(const EC_GROUP *, EC_POINT *r, const EC_POINT *a,
 495                             const EC_POINT *b, BN_CTX *);
 496 int ossl_ec_GF2m_simple_dbl(const EC_GROUP *, EC_POINT *r, const EC_POINT *a,
 497                             BN_CTX *);
 498 int ossl_ec_GF2m_simple_invert(const EC_GROUP *, EC_POINT *, BN_CTX *);
 499 int ossl_ec_GF2m_simple_is_at_infinity(const EC_GROUP *, const EC_POINT *);
 500 int ossl_ec_GF2m_simple_is_on_curve(const EC_GROUP *, const EC_POINT *, BN_CTX *);
 501 int ossl_ec_GF2m_simple_cmp(const EC_GROUP *, const EC_POINT *a,
 502                             const EC_POINT *b, BN_CTX *);
 503 int ossl_ec_GF2m_simple_make_affine(const EC_GROUP *, EC_POINT *, BN_CTX *);
 504 int ossl_ec_GF2m_simple_points_make_affine(const EC_GROUP *, size_t num,
 505                                            EC_POINT *[], BN_CTX *);
 506 int ossl_ec_GF2m_simple_field_mul(const EC_GROUP *, BIGNUM *r, const BIGNUM *a,
 507                                   const BIGNUM *b, BN_CTX *);
 508 int ossl_ec_GF2m_simple_field_sqr(const EC_GROUP *, BIGNUM *r, const BIGNUM *a,
 509                                   BN_CTX *);
 510 int ossl_ec_GF2m_simple_field_div(const EC_GROUP *, BIGNUM *r, const BIGNUM *a,
 511                                  const BIGNUM *b, BN_CTX *);
 512
 513 #ifndef OPENSSL_NO_EC_NISTP_64_GCC_128
 514 # ifdef B_ENDIAN
 515 #  error "Can not enable ec_nistp_64_gcc_128 on big-endian systems"
 516 # endif
 517
 518 /* method functions in ecp_nistp224.c */
 519 int ossl_ec_GFp_nistp224_group_init(EC_GROUP *group);
 520 int ossl_ec_GFp_nistp224_group_set_curve(EC_GROUP *group, const BIGNUM *p,
 521                                          const BIGNUM *a, const BIGNUM *n,
 522                                          BN_CTX *);
 523 int ossl_ec_GFp_nistp224_point_get_affine_coordinates(const EC_GROUP *group,
 524                                                       const EC_POINT *point,
 525                                                       BIGNUM *x, BIGNUM *y,
 526                                                       BN_CTX *ctx);
 527 int ossl_ec_GFp_nistp224_mul(const EC_GROUP *group, EC_POINT *r,
 528                              const BIGNUM *scalar, size_t num,
 529                              const EC_POINT *points[], const BIGNUM *scalars[],
 530                              BN_CTX *);
 531 int ossl_ec_GFp_nistp224_points_mul(const EC_GROUP *group, EC_POINT *r,
 532                                     const BIGNUM *scalar, size_t num,
 533                                     const EC_POINT *points[],
 534                                     const BIGNUM *scalars[], BN_CTX *ctx);
 535 int ossl_ec_GFp_nistp224_precompute_mult(EC_GROUP *group, BN_CTX *ctx);
 536 int ossl_ec_GFp_nistp224_have_precompute_mult(const EC_GROUP *group);
 537
 538 /* method functions in ecp_nistp256.c */
 539 int ossl_ec_GFp_nistp256_group_init(EC_GROUP *group);
 540 int ossl_ec_GFp_nistp256_group_set_curve(EC_GROUP *group, const BIGNUM *p,
 541                                          const BIGNUM *a, const BIGNUM *n,
 542                                          BN_CTX *);
 543 int ossl_ec_GFp_nistp256_point_get_affine_coordinates(const EC_GROUP *group,
 544                                                       const EC_POINT *point,
 545                                                       BIGNUM *x, BIGNUM *y,
 546                                                       BN_CTX *ctx);
 547 int ossl_ec_GFp_nistp256_mul(const EC_GROUP *group, EC_POINT *r,
 548                              const BIGNUM *scalar, size_t num,
 549                              const EC_POINT *points[], const BIGNUM *scalars[],
 550                              BN_CTX *);
 551 int ossl_ec_GFp_nistp256_points_mul(const EC_GROUP *group, EC_POINT *r,
 552                                     const BIGNUM *scalar, size_t num,
 553                                     const EC_POINT *points[],
 554                                     const BIGNUM *scalars[], BN_CTX *ctx);
 555 int ossl_ec_GFp_nistp256_precompute_mult(EC_GROUP *group, BN_CTX *ctx);
 556 int ossl_ec_GFp_nistp256_have_precompute_mult(const EC_GROUP *group);
 557
 558 /* method functions in ecp_nistp384.c */
 559 int ossl_ec_GFp_nistp384_group_init(EC_GROUP *group);
 560 int ossl_ec_GFp_nistp384_group_set_curve(EC_GROUP *group, const BIGNUM *p,
 561                                          const BIGNUM *a, const BIGNUM *n,
 562                                          BN_CTX *);
 563 int ossl_ec_GFp_nistp384_point_get_affine_coordinates(const EC_GROUP *group,
 564                                                       const EC_POINT *point,
 565                                                       BIGNUM *x, BIGNUM *y,
 566                                                       BN_CTX *ctx);
 567 int ossl_ec_GFp_nistp384_mul(const EC_GROUP *group, EC_POINT *r,
 568                              const BIGNUM *scalar, size_t num,
 569                              const EC_POINT *points[], const BIGNUM *scalars[],
 570                              BN_CTX *);
 571 int ossl_ec_GFp_nistp384_points_mul(const EC_GROUP *group, EC_POINT *r,
 572                                     const BIGNUM *scalar, size_t num,
 573                                     const EC_POINT *points[],
 574                                     const BIGNUM *scalars[], BN_CTX *ctx);
 575 int ossl_ec_GFp_nistp384_precompute_mult(EC_GROUP *group, BN_CTX *ctx);
 576 int ossl_ec_GFp_nistp384_have_precompute_mult(const EC_GROUP *group);
 577 const EC_METHOD *ossl_ec_GFp_nistp384_method(void);
 578
 579 /* method functions in ecp_nistp521.c */
 580 int ossl_ec_GFp_nistp521_group_init(EC_GROUP *group);
 581 int ossl_ec_GFp_nistp521_group_set_curve(EC_GROUP *group, const BIGNUM *p,
 582                                          const BIGNUM *a, const BIGNUM *n,
 583                                          BN_CTX *);
 584 int ossl_ec_GFp_nistp521_point_get_affine_coordinates(const EC_GROUP *group,
 585                                                       const EC_POINT *point,
 586                                                       BIGNUM *x, BIGNUM *y,
 587                                                       BN_CTX *ctx);
 588 int ossl_ec_GFp_nistp521_mul(const EC_GROUP *group, EC_POINT *r,
 589                              const BIGNUM *scalar, size_t num,
 590                              const EC_POINT *points[], const BIGNUM *scalars[],
 591                              BN_CTX *);
 592 int ossl_ec_GFp_nistp521_points_mul(const EC_GROUP *group, EC_POINT *r,
 593                                     const BIGNUM *scalar, size_t num,
 594                                     const EC_POINT *points[],
 595                                     const BIGNUM *scalars[], BN_CTX *ctx);
 596 int ossl_ec_GFp_nistp521_precompute_mult(EC_GROUP *group, BN_CTX *ctx);
 597 int ossl_ec_GFp_nistp521_have_precompute_mult(const EC_GROUP *group);
 598
 599 /* utility functions in ecp_nistputil.c */
 600 void ossl_ec_GFp_nistp_points_make_affine_internal(size_t num, void *point_array,
 601                                                    size_t felem_size,
 602                                                    void *tmp_felems,
 603                                                    void (*felem_one) (void *out),
 604                                                    int (*felem_is_zero)
 605                                                        (const void *in),
 606                                                    void (*felem_assign)
 607                                                        (void *out, const void *in),
 608                                                    void (*felem_square)
 609                                                        (void *out, const void *in),
 610                                                    void (*felem_mul)
 611                                                        (void *out,
 612                                                         const void *in1,
 613                                                         const void *in2),
 614                                                    void (*felem_inv)
 615                                                        (void *out, const void *in),
 616                                                    void (*felem_contract)
 617                                                        (void *out, const void *in));
 618 void ossl_ec_GFp_nistp_recode_scalar_bits(unsigned char *sign,
 619                                           unsigned char *digit,
 620                                           unsigned char in);
 621 #endif
 622 int ossl_ec_group_simple_order_bits(const EC_GROUP *group);
 623
 624 /**
 625  *  Creates a new EC_GROUP object
 626  *  \param   libctx The associated library context or NULL for the default
 627  *                  library context
 628  *  \param   propq  Any property query string
 629  *  \param   meth   EC_METHOD to use
 630  *  \return  newly created EC_GROUP object or NULL in case of an error.
 631  */
 632 EC_GROUP *ossl_ec_group_new_ex(OSSL_LIB_CTX *libctx, const char *propq,
 633                                const EC_METHOD *meth);
 634
 635 #ifdef ECP_NISTZ256_ASM
 636 /** Returns GFp methods using montgomery multiplication, with x86-64 optimized
 637  * P256. See http://eprint.iacr.org/2013/816.
 638  *  \return  EC_METHOD object
 639  */
 640 const EC_METHOD *EC_GFp_nistz256_method(void);
 641 #endif
 642 #ifdef S390X_EC_ASM
 643 const EC_METHOD *EC_GFp_s390x_nistp256_method(void);
 644 const EC_METHOD *EC_GFp_s390x_nistp384_method(void);
 645 const EC_METHOD *EC_GFp_s390x_nistp521_method(void);
 646 #endif
 647
 648 size_t ossl_ec_key_simple_priv2oct(const EC_KEY *eckey,
 649                                    unsigned char *buf, size_t len);
 650 int ossl_ec_key_simple_oct2priv(EC_KEY *eckey, const unsigned char *buf,
 651                                 size_t len);
 652 int ossl_ec_key_simple_generate_key(EC_KEY *eckey);
 653 int ossl_ec_key_simple_generate_public_key(EC_KEY *eckey);
 654 int ossl_ec_key_simple_check_key(const EC_KEY *eckey);
 655
 656 #ifdef ECP_SM2P256_ASM
 657 /* Returns optimized methods for SM2 */
 658 const EC_METHOD *EC_GFp_sm2p256_method(void);
 659 #endif
 660
 661 int ossl_ec_curve_nid_from_params(const EC_GROUP *group, BN_CTX *ctx);
 662
 663 /* EC_METHOD definitions */
 664
 665 struct ec_key_method_st {
 666     const char *name;
 667     int32_t flags;
 668     int (*init)(EC_KEY *key);
 669     void (*finish)(EC_KEY *key);
 670     int (*copy)(EC_KEY *dest, const EC_KEY *src);
 671     int (*set_group)(EC_KEY *key, const EC_GROUP *grp);
 672     int (*set_private)(EC_KEY *key, const BIGNUM *priv_key);
 673     int (*set_public)(EC_KEY *key, const EC_POINT *pub_key);
 674     int (*keygen)(EC_KEY *key);
 675     int (*compute_key)(unsigned char **pout, size_t *poutlen,
 676                        const EC_POINT *pub_key, const EC_KEY *ecdh);
 677     int (*sign)(int type, const unsigned char *dgst, int dlen, unsigned char
 678                 *sig, unsigned int *siglen, const BIGNUM *kinv,
 679                 const BIGNUM *r, EC_KEY *eckey);
 680     int (*sign_setup)(EC_KEY *eckey, BN_CTX *ctx_in, BIGNUM **kinvp,
 681                       BIGNUM **rp);
 682     ECDSA_SIG *(*sign_sig)(const unsigned char *dgst, int dgst_len,
 683                            const BIGNUM *in_kinv, const BIGNUM *in_r,
 684                            EC_KEY *eckey);
 685
 686     int (*verify)(int type, const unsigned char *dgst, int dgst_len,
 687                   const unsigned char *sigbuf, int sig_len, EC_KEY *eckey);
 688     int (*verify_sig)(const unsigned char *dgst, int dgst_len,
 689                       const ECDSA_SIG *sig, EC_KEY *eckey);
 690 };
 691
 692 #define EC_KEY_METHOD_DYNAMIC   1
 693
 694 EC_KEY *ossl_ec_key_new_method_int(OSSL_LIB_CTX *libctx, const char *propq,
 695                                    ENGINE *engine);
 696
 697 int ossl_ec_key_gen(EC_KEY *eckey);
 698 int ossl_ecdh_compute_key(unsigned char **pout, size_t *poutlen,
 699                           const EC_POINT *pub_key, const EC_KEY *ecdh);
 700 int ossl_ecdh_simple_compute_key(unsigned char **pout, size_t *poutlen,
 701                                  const EC_POINT *pub_key, const EC_KEY *ecdh);
 702
 703 struct ECDSA_SIG_st {
 704     BIGNUM *r;
 705     BIGNUM *s;
 706 };
 707
 708 int ossl_ecdsa_sign_setup(EC_KEY *eckey, BN_CTX *ctx_in, BIGNUM **kinvp,
 709                           BIGNUM **rp);
 710 int ossl_ecdsa_sign(int type, const unsigned char *dgst, int dlen,
 711                     unsigned char *sig, unsigned int *siglen,
 712                     const BIGNUM *kinv, const BIGNUM *r, EC_KEY *eckey);
 713 ECDSA_SIG *ossl_ecdsa_sign_sig(const unsigned char *dgst, int dgst_len,
 714                                const BIGNUM *in_kinv, const BIGNUM *in_r,
 715                                EC_KEY *eckey);
 716 int ossl_ecdsa_verify(int type, const unsigned char *dgst, int dgst_len,
 717                       const unsigned char *sigbuf, int sig_len, EC_KEY *eckey);
 718 int ossl_ecdsa_verify_sig(const unsigned char *dgst, int dgst_len,
 719                           const ECDSA_SIG *sig, EC_KEY *eckey);
 720 int ossl_ecdsa_simple_sign_setup(EC_KEY *eckey, BN_CTX *ctx_in, BIGNUM **kinvp,
 721                                  BIGNUM **rp);
 722 ECDSA_SIG *ossl_ecdsa_simple_sign_sig(const unsigned char *dgst, int dgst_len,
 723                                       const BIGNUM *in_kinv, const BIGNUM *in_r,
 724                                       EC_KEY *eckey);
 725 int ossl_ecdsa_simple_verify_sig(const unsigned char *dgst, int dgst_len,
 726                                  const ECDSA_SIG *sig, EC_KEY *eckey);
 727
 728
 729 /*-
 730  * This functions computes a single point multiplication over the EC group,
 731  * using, at a high level, a Montgomery ladder with conditional swaps, with
 732  * various timing attack defenses.
 733  *
 734  * It performs either a fixed point multiplication
 735  *          (scalar * generator)
 736  * when point is NULL, or a variable point multiplication
 737  *          (scalar * point)
 738  * when point is not NULL.
 739  *
 740  * `scalar` cannot be NULL and should be in the range [0,n) otherwise all
 741  * constant time bets are off (where n is the cardinality of the EC group).
 742  *
 743  * This function expects `group->order` and `group->cardinality` to be well
 744  * defined and non-zero: it fails with an error code otherwise.
 745  *
 746  * NB: This says nothing about the constant-timeness of the ladder step
 747  * implementation (i.e., the default implementation is based on EC_POINT_add and
 748  * EC_POINT_dbl, which of course are not constant time themselves) or the
 749  * underlying multiprecision arithmetic.
 750  *
 751  * The product is stored in `r`.
 752  *
 753  * This is an internal function: callers are in charge of ensuring that the
 754  * input parameters `group`, `r`, `scalar` and `ctx` are not NULL.
 755  *
 756  * Returns 1 on success, 0 otherwise.
 757  */
 758 int ossl_ec_scalar_mul_ladder(const EC_GROUP *group, EC_POINT *r,
 759                               const BIGNUM *scalar, const EC_POINT *point,
 760                               BN_CTX *ctx);
 761
 762 int ossl_ec_point_blind_coordinates(const EC_GROUP *group, EC_POINT *p,
 763                                     BN_CTX *ctx);
 764
 765 static ossl_inline int ec_point_ladder_pre(const EC_GROUP *group,
 766                                            EC_POINT *r, EC_POINT *s,
 767                                            EC_POINT *p, BN_CTX *ctx)
 768 {
 769     if (group->meth->ladder_pre != NULL)
 770         return group->meth->ladder_pre(group, r, s, p, ctx);
 771
 772     if (!EC_POINT_copy(s, p)
 773         || !EC_POINT_dbl(group, r, s, ctx))
 774         return 0;
 775
 776     return 1;
 777 }
 778
 779 static ossl_inline int ec_point_ladder_step(const EC_GROUP *group,
 780                                             EC_POINT *r, EC_POINT *s,
 781                                             EC_POINT *p, BN_CTX *ctx)
 782 {
 783     if (group->meth->ladder_step != NULL)
 784         return group->meth->ladder_step(group, r, s, p, ctx);
 785
 786     if (!EC_POINT_add(group, s, r, s, ctx)
 787         || !EC_POINT_dbl(group, r, r, ctx))
 788         return 0;
 789
 790     return 1;
 791
 792 }
 793
 794 static ossl_inline int ec_point_ladder_post(const EC_GROUP *group,
 795                                             EC_POINT *r, EC_POINT *s,
 796                                             EC_POINT *p, BN_CTX *ctx)
 797 {
 798     if (group->meth->ladder_post != NULL)
 799         return group->meth->ladder_post(group, r, s, p, ctx);
 800
 801     return 1;
 802 }