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ecp.h
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1 
17 /*
18  * Copyright The Mbed TLS Contributors
19  * SPDX-License-Identifier: Apache-2.0 OR GPL-2.0-or-later
20  *
21  * This file is provided under the Apache License 2.0, or the
22  * GNU General Public License v2.0 or later.
23  *
24  * **********
25  * Apache License 2.0:
26  *
27  * Licensed under the Apache License, Version 2.0 (the "License"); you may
28  * not use this file except in compliance with the License.
29  * You may obtain a copy of the License at
30  *
31  * http://www.apache.org/licenses/LICENSE-2.0
32  *
33  * Unless required by applicable law or agreed to in writing, software
34  * distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
35  * WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
36  * See the License for the specific language governing permissions and
37  * limitations under the License.
38  *
39  * **********
40  *
41  * **********
42  * GNU General Public License v2.0 or later:
43  *
44  * This program is free software; you can redistribute it and/or modify
45  * it under the terms of the GNU General Public License as published by
46  * the Free Software Foundation; either version 2 of the License, or
47  * (at your option) any later version.
48  *
49  * This program is distributed in the hope that it will be useful,
50  * but WITHOUT ANY WARRANTY; without even the implied warranty of
51  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
52  * GNU General Public License for more details.
53  *
54  * You should have received a copy of the GNU General Public License along
55  * with this program; if not, write to the Free Software Foundation, Inc.,
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57  *
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59  */
60 
61 #ifndef MBEDTLS_ECP_H
62 #define MBEDTLS_ECP_H
63 
64 #if !defined(MBEDTLS_CONFIG_FILE)
65 #include "config.h"
66 #else
67 #include MBEDTLS_CONFIG_FILE
68 #endif
69 
70 #include "bignum.h"
71 
72 /*
73  * ECP error codes
74  */
75 #define MBEDTLS_ERR_ECP_BAD_INPUT_DATA -0x4F80
76 #define MBEDTLS_ERR_ECP_BUFFER_TOO_SMALL -0x4F00
77 #define MBEDTLS_ERR_ECP_FEATURE_UNAVAILABLE -0x4E80
78 #define MBEDTLS_ERR_ECP_VERIFY_FAILED -0x4E00
79 #define MBEDTLS_ERR_ECP_ALLOC_FAILED -0x4D80
80 #define MBEDTLS_ERR_ECP_RANDOM_FAILED -0x4D00
81 #define MBEDTLS_ERR_ECP_INVALID_KEY -0x4C80
82 #define MBEDTLS_ERR_ECP_SIG_LEN_MISMATCH -0x4C00
84 /* MBEDTLS_ERR_ECP_HW_ACCEL_FAILED is deprecated and should not be used. */
85 #define MBEDTLS_ERR_ECP_HW_ACCEL_FAILED -0x4B80
87 #define MBEDTLS_ERR_ECP_IN_PROGRESS -0x4B00
89 #ifdef __cplusplus
90 extern "C" {
91 #endif
92 
102 typedef enum
103 {
119 
125 #define MBEDTLS_ECP_DP_MAX 12
126 
131 {
135  const char *name;
137 
149 typedef struct mbedtls_ecp_point
150 {
154 }
156 
157 /* Determine the minimum safe value of MBEDTLS_ECP_MAX_BITS. */
158 #if !defined(MBEDTLS_ECP_C)
159 #define MBEDTLS_ECP_MAX_BITS_MIN 0
160 /* Note: the curves must be listed in DECREASING size! */
161 #elif defined(MBEDTLS_ECP_DP_SECP521R1_ENABLED)
162 #define MBEDTLS_ECP_MAX_BITS_MIN 521
163 #elif defined(MBEDTLS_ECP_DP_BP512R1_ENABLED)
164 #define MBEDTLS_ECP_MAX_BITS_MIN 512
165 #elif defined(MBEDTLS_ECP_DP_CURVE448_ENABLED)
166 #define MBEDTLS_ECP_MAX_BITS_MIN 448
167 #elif defined(MBEDTLS_ECP_DP_BP384R1_ENABLED)
168 #define MBEDTLS_ECP_MAX_BITS_MIN 384
169 #elif defined(MBEDTLS_ECP_DP_SECP384R1_ENABLED)
170 #define MBEDTLS_ECP_MAX_BITS_MIN 384
171 #elif defined(MBEDTLS_ECP_DP_BP256R1_ENABLED)
172 #define MBEDTLS_ECP_MAX_BITS_MIN 256
173 #elif defined(MBEDTLS_ECP_DP_SECP256K1_ENABLED)
174 #define MBEDTLS_ECP_MAX_BITS_MIN 256
175 #elif defined(MBEDTLS_ECP_DP_SECP256R1_ENABLED)
176 #define MBEDTLS_ECP_MAX_BITS_MIN 256
177 #elif defined(MBEDTLS_ECP_DP_CURVE25519_ENABLED)
178 #define MBEDTLS_ECP_MAX_BITS_MIN 255
179 #elif defined(MBEDTLS_ECP_DP_SECP224K1_ENABLED)
180 #define MBEDTLS_ECP_MAX_BITS_MIN 225 // n is slightly above 2^224
181 #elif defined(MBEDTLS_ECP_DP_SECP224R1_ENABLED)
182 #define MBEDTLS_ECP_MAX_BITS_MIN 224
183 #elif defined(MBEDTLS_ECP_DP_SECP192K1_ENABLED)
184 #define MBEDTLS_ECP_MAX_BITS_MIN 192
185 #elif defined(MBEDTLS_ECP_DP_SECP192R1_ENABLED)
186 #define MBEDTLS_ECP_MAX_BITS_MIN 192
187 #else
188 #error "MBEDTLS_ECP_C enabled, but no curve?"
189 #endif
190 
191 #if !defined(MBEDTLS_ECP_ALT)
192 /*
193  * default mbed TLS elliptic curve arithmetic implementation
194  *
195  * (in case MBEDTLS_ECP_ALT is defined then the developer has to provide an
196  * alternative implementation for the whole module and it will replace this
197  * one.)
198  */
199 
232 typedef struct mbedtls_ecp_group
233 {
242  size_t pbits;
243  size_t nbits;
246  unsigned int h;
249  int (*t_pre)(mbedtls_ecp_point *, void *);
250  int (*t_post)(mbedtls_ecp_point *, void *);
251  void *t_data;
253  size_t T_size;
254 }
256 
265 #if defined(MBEDTLS_ECP_MAX_BITS)
266 
267 #if MBEDTLS_ECP_MAX_BITS < MBEDTLS_ECP_MAX_BITS_MIN
268 #error "MBEDTLS_ECP_MAX_BITS is smaller than the largest supported curve"
269 #endif
270 
271 #else
272 
275 #define MBEDTLS_ECP_MAX_BITS 521
276 #endif
277 
278 #define MBEDTLS_ECP_MAX_BYTES ( ( MBEDTLS_ECP_MAX_BITS + 7 ) / 8 )
279 #define MBEDTLS_ECP_MAX_PT_LEN ( 2 * MBEDTLS_ECP_MAX_BYTES + 1 )
280 
281 #if !defined(MBEDTLS_ECP_WINDOW_SIZE)
282 /*
283  * Maximum "window" size used for point multiplication.
284  * Default: 6.
285  * Minimum value: 2. Maximum value: 7.
286  *
287  * Result is an array of at most ( 1 << ( MBEDTLS_ECP_WINDOW_SIZE - 1 ) )
288  * points used for point multiplication. This value is directly tied to EC
289  * peak memory usage, so decreasing it by one should roughly cut memory usage
290  * by two (if large curves are in use).
291  *
292  * Reduction in size may reduce speed, but larger curves are impacted first.
293  * Sample performances (in ECDHE handshakes/s, with FIXED_POINT_OPTIM = 1):
294  * w-size: 6 5 4 3 2
295  * 521 145 141 135 120 97
296  * 384 214 209 198 177 146
297  * 256 320 320 303 262 226
298  * 224 475 475 453 398 342
299  * 192 640 640 633 587 476
300  */
301 #define MBEDTLS_ECP_WINDOW_SIZE 6
302 #endif /* MBEDTLS_ECP_WINDOW_SIZE */
303 
304 #if !defined(MBEDTLS_ECP_FIXED_POINT_OPTIM)
305 /*
306  * Trade memory for speed on fixed-point multiplication.
307  *
308  * This speeds up repeated multiplication of the generator (that is, the
309  * multiplication in ECDSA signatures, and half of the multiplications in
310  * ECDSA verification and ECDHE) by a factor roughly 3 to 4.
311  *
312  * The cost is increasing EC peak memory usage by a factor roughly 2.
313  *
314  * Change this value to 0 to reduce peak memory usage.
315  */
316 #define MBEDTLS_ECP_FIXED_POINT_OPTIM 1
317 #endif /* MBEDTLS_ECP_FIXED_POINT_OPTIM */
318 
319 /* \} name SECTION: Module settings */
320 
321 #else /* MBEDTLS_ECP_ALT */
322 #include "ecp_alt.h"
323 #endif /* MBEDTLS_ECP_ALT */
324 
325 #if defined(MBEDTLS_ECP_RESTARTABLE)
326 
332 typedef struct mbedtls_ecp_restart_mul mbedtls_ecp_restart_mul_ctx;
333 
339 typedef struct mbedtls_ecp_restart_muladd mbedtls_ecp_restart_muladd_ctx;
340 
344 typedef struct
345 {
346  unsigned ops_done;
347  unsigned depth;
348  mbedtls_ecp_restart_mul_ctx *rsm;
349  mbedtls_ecp_restart_muladd_ctx *ma;
351 
352 /*
353  * Operation counts for restartable functions
354  */
355 #define MBEDTLS_ECP_OPS_CHK 3
356 #define MBEDTLS_ECP_OPS_DBL 8
357 #define MBEDTLS_ECP_OPS_ADD 11
358 #define MBEDTLS_ECP_OPS_INV 120
371 int mbedtls_ecp_check_budget( const mbedtls_ecp_group *grp,
372  mbedtls_ecp_restart_ctx *rs_ctx,
373  unsigned ops );
374 
375 /* Utility macro for checking and updating ops budget */
376 #define MBEDTLS_ECP_BUDGET( ops ) \
377  MBEDTLS_MPI_CHK( mbedtls_ecp_check_budget( grp, rs_ctx, \
378  (unsigned) (ops) ) );
379 
380 #else /* MBEDTLS_ECP_RESTARTABLE */
381 
382 #define MBEDTLS_ECP_BUDGET( ops ) /* no-op; for compatibility */
383 
384 /* We want to declare restartable versions of existing functions anyway */
386 
387 #endif /* MBEDTLS_ECP_RESTARTABLE */
388 
397 typedef struct mbedtls_ecp_keypair
398 {
402 }
404 
405 /*
406  * Point formats, from RFC 4492's enum ECPointFormat
407  */
408 #define MBEDTLS_ECP_PF_UNCOMPRESSED 0
409 #define MBEDTLS_ECP_PF_COMPRESSED 1
411 /*
412  * Some other constants from RFC 4492
413  */
414 #define MBEDTLS_ECP_TLS_NAMED_CURVE 3
416 #if defined(MBEDTLS_ECP_RESTARTABLE)
417 
474 void mbedtls_ecp_set_max_ops( unsigned max_ops );
475 
482 int mbedtls_ecp_restart_is_enabled( void );
483 #endif /* MBEDTLS_ECP_RESTARTABLE */
484 
493 
503 
514 
525 
536 
543 
554 
561 
568 
577 
586 
587 #if defined(MBEDTLS_ECP_RESTARTABLE)
588 
594 void mbedtls_ecp_restart_init( mbedtls_ecp_restart_ctx *ctx );
595 
603 void mbedtls_ecp_restart_free( mbedtls_ecp_restart_ctx *ctx );
604 #endif /* MBEDTLS_ECP_RESTARTABLE */
605 
618 
631  const mbedtls_ecp_group *src );
632 
643 
654 
668  const mbedtls_ecp_point *Q );
669 
683  const char *x, const char *y );
684 
706  int format, size_t *olen,
707  unsigned char *buf, size_t buflen );
708 
733  const unsigned char *buf, size_t ilen );
734 
755  const unsigned char **buf, size_t len );
756 
780  const mbedtls_ecp_point *pt,
781  int format, size_t *olen,
782  unsigned char *buf, size_t blen );
783 
802 
821  const unsigned char **buf, size_t len );
822 
842  const unsigned char **buf,
843  size_t len );
863  size_t *olen,
864  unsigned char *buf, size_t blen );
865 
903  const mbedtls_mpi *m, const mbedtls_ecp_point *P,
904  int (*f_rng)(void *, unsigned char *, size_t), void *p_rng );
905 
937  const mbedtls_mpi *m, const mbedtls_ecp_point *P,
938  int (*f_rng)(void *, unsigned char *, size_t), void *p_rng,
939  mbedtls_ecp_restart_ctx *rs_ctx );
940 
971  const mbedtls_mpi *m, const mbedtls_ecp_point *P,
972  const mbedtls_mpi *n, const mbedtls_ecp_point *Q );
973 
1010  const mbedtls_mpi *m, const mbedtls_ecp_point *P,
1011  const mbedtls_mpi *n, const mbedtls_ecp_point *Q,
1012  mbedtls_ecp_restart_ctx *rs_ctx );
1013 
1042  const mbedtls_ecp_point *pt );
1043 
1064  const mbedtls_mpi *d );
1065 
1082  mbedtls_mpi *d,
1083  int (*f_rng)(void *, unsigned char *, size_t),
1084  void *p_rng );
1085 
1114  const mbedtls_ecp_point *G,
1116  int (*f_rng)(void *, unsigned char *, size_t),
1117  void *p_rng );
1118 
1143  mbedtls_ecp_point *Q,
1144  int (*f_rng)(void *, unsigned char *, size_t),
1145  void *p_rng );
1146 
1161  int (*f_rng)(void *, unsigned char *, size_t),
1162  void *p_rng );
1163 
1182  const mbedtls_ecp_keypair *prv );
1183 
1184 #if defined(MBEDTLS_SELF_TEST)
1185 
1192 int mbedtls_ecp_self_test( int verbose );
1193 
1194 #endif /* MBEDTLS_SELF_TEST */
1195 
1196 #ifdef __cplusplus
1197 }
1198 #endif
1199 
1200 #endif /* ecp.h */
uint16_t tls_id
Definition: ecp.h:133
int(* modp)(mbedtls_mpi *)
Definition: ecp.h:247
int mbedtls_ecp_is_zero(mbedtls_ecp_point *pt)
This function checks if a point is the point at infinity.
mbedtls_mpi N
Definition: ecp.h:241
#define R(b, x)
Definition: sha2.c:134
int mbedtls_ecp_mul_restartable(mbedtls_ecp_group *grp, mbedtls_ecp_point *R, const mbedtls_mpi *m, const mbedtls_ecp_point *P, int(*f_rng)(void *, unsigned char *, size_t), void *p_rng, mbedtls_ecp_restart_ctx *rs_ctx)
This function performs multiplication of a point by an integer: R = m * P in a restartable way.
int(* t_post)(mbedtls_ecp_point *, void *)
Definition: ecp.h:250
mbedtls_mpi Z
Definition: ecp.h:153
int mbedtls_ecp_muladd(mbedtls_ecp_group *grp, mbedtls_ecp_point *R, const mbedtls_mpi *m, const mbedtls_ecp_point *P, const mbedtls_mpi *n, const mbedtls_ecp_point *Q)
This function performs multiplication and addition of two points by integers: R = m * P + n * Q.
int mbedtls_ecp_check_pub_priv(const mbedtls_ecp_keypair *pub, const mbedtls_ecp_keypair *prv)
This function checks that the keypair objects pub and prv have the same group and the same public poi...
int mbedtls_ecp_point_read_binary(const mbedtls_ecp_group *grp, mbedtls_ecp_point *P, const unsigned char *buf, size_t ilen)
This function imports a point from unsigned binary data.
#define pt(x, y)
Definition: drawing.c:79
mbedtls_mpi Y
Definition: ecp.h:152
int mbedtls_ecp_muladd_restartable(mbedtls_ecp_group *grp, mbedtls_ecp_point *R, const mbedtls_mpi *m, const mbedtls_ecp_point *P, const mbedtls_mpi *n, const mbedtls_ecp_point *Q, mbedtls_ecp_restart_ctx *rs_ctx)
This function performs multiplication and addition of two points by integers: R = m * P + n * Q in a ...
mbedtls_ecp_group grp
Definition: ecp.h:399
struct mbedtls_ecp_curve_info mbedtls_ecp_curve_info
The ECP key-pair structure.
Definition: ecp.h:397
GLdouble n
Definition: glext.h:7729
int mbedtls_ecp_set_zero(mbedtls_ecp_point *pt)
This function sets a point to the point at infinity.
GLint GLint GLint GLint GLint x
Definition: gl.h:1548
int mbedtls_ecp_copy(mbedtls_ecp_point *P, const mbedtls_ecp_point *Q)
This function copies the contents of point Q into point P.
const mbedtls_ecp_group_id * mbedtls_ecp_grp_id_list(void)
This function retrieves the list of internal group identifiers of all supported curves in the order o...
int mbedtls_ecp_group_copy(mbedtls_ecp_group *dst, const mbedtls_ecp_group *src)
This function copies the contents of group src into group dst.
ULONG G
Definition: xcpt4u.c:549
unsigned short int uint16_t
Definition: acefiex.h:54
size_t nbits
Definition: ecp.h:243
struct mbedtls_ecp_group mbedtls_ecp_group
The ECP group structure.
int mbedtls_ecp_gen_keypair(mbedtls_ecp_group *grp, mbedtls_mpi *d, mbedtls_ecp_point *Q, int(*f_rng)(void *, unsigned char *, size_t), void *p_rng)
This function generates an ECP keypair.
const GLfloat * m
Definition: glext.h:10848
GLint GLint GLsizei GLsizei GLsizei GLint GLenum format
Definition: gl.h:1546
void mbedtls_ecp_point_free(mbedtls_ecp_point *pt)
This function frees the components of a point.
int mbedtls_ecp_gen_privkey(const mbedtls_ecp_group *grp, mbedtls_mpi *d, int(*f_rng)(void *, unsigned char *, size_t), void *p_rng)
This function generates a private key.
void mbedtls_ecp_keypair_init(mbedtls_ecp_keypair *key)
This function initializes a key pair as an invalid one.
#define verbose
Definition: rosglue.h:36
size_t pbits
Definition: ecp.h:242
mbedtls_mpi X
Definition: ecp.h:151
GLenum GLuint GLenum GLsizei const GLchar * buf
Definition: glext.h:7751
Multi-precision integer library.
int mbedtls_ecp_gen_key(mbedtls_ecp_group_id grp_id, mbedtls_ecp_keypair *key, int(*f_rng)(void *, unsigned char *, size_t), void *p_rng)
This function generates an ECP key.
The ECP group structure.
Definition: ecp.h:232
int mbedtls_ecp_check_privkey(const mbedtls_ecp_group *grp, const mbedtls_mpi *d)
This function checks that an mbedtls_mpi is a valid private key for this curve.
mbedtls_ecp_group_id id
Definition: ecp.h:234
const mbedtls_ecp_curve_info * mbedtls_ecp_curve_info_from_grp_id(mbedtls_ecp_group_id grp_id)
This function retrieves curve information from an internal group identifier.
int mbedtls_ecp_tls_write_group(const mbedtls_ecp_group *grp, size_t *olen, unsigned char *buf, size_t blen)
This function exports an elliptic curve as a TLS ECParameters record as defined in RFC 4492,...
void mbedtls_ecp_group_free(mbedtls_ecp_group *grp)
This function frees the components of an ECP group.
int mbedtls_ecp_mul(mbedtls_ecp_group *grp, mbedtls_ecp_point *R, const mbedtls_mpi *m, const mbedtls_ecp_point *P, int(*f_rng)(void *, unsigned char *, size_t), void *p_rng)
This function performs a scalar multiplication of a point by an integer: R = m * P.
int mbedtls_ecp_check_pubkey(const mbedtls_ecp_group *grp, const mbedtls_ecp_point *pt)
This function checks that a point is a valid public key on this curve.
mbedtls_mpi A
Definition: ecp.h:236
mbedtls_mpi P
Definition: ecp.h:235
void mbedtls_ecp_keypair_free(mbedtls_ecp_keypair *key)
This function frees the components of a key pair.
struct mbedtls_ecp_keypair mbedtls_ecp_keypair
The ECP key-pair structure.
int mbedtls_ecp_tls_read_group(mbedtls_ecp_group *grp, const unsigned char **buf, size_t len)
This function sets up an ECP group context from a TLS ECParameters record as defined in RFC 4492,...
void mbedtls_ecp_restart_ctx
Definition: ecp.h:385
mbedtls_ecp_point Q
Definition: ecp.h:401
void * t_data
Definition: ecp.h:251
void mbedtls_ecp_point_init(mbedtls_ecp_point *pt)
This function initializes a point as zero.
mbedtls_ecp_group_id
Definition: ecp.h:102
int mbedtls_ecp_point_read_string(mbedtls_ecp_point *P, int radix, const char *x, const char *y)
This function imports a non-zero point from two ASCII strings.
GLint GLint GLsizei GLsizei GLsizei depth
Definition: gl.h:1546
int mbedtls_ecp_point_write_binary(const mbedtls_ecp_group *grp, const mbedtls_ecp_point *P, int format, size_t *olen, unsigned char *buf, size_t buflen)
This function exports a point into unsigned binary data.
GLenum GLsizei len
Definition: glext.h:6722
const mbedtls_ecp_curve_info * mbedtls_ecp_curve_info_from_tls_id(uint16_t tls_id)
This function retrieves curve information from a TLS NamedCurve value.
int mbedtls_ecp_tls_read_point(const mbedtls_ecp_group *grp, mbedtls_ecp_point *pt, const unsigned char **buf, size_t len)
This function imports a point from a TLS ECPoint record.
GLenum src
Definition: glext.h:6340
mbedtls_ecp_group_id grp_id
Definition: ecp.h:132
int mbedtls_ecp_tls_read_group_id(mbedtls_ecp_group_id *grp, const unsigned char **buf, size_t len)
This function extracts an elliptic curve group ID from a TLS ECParameters record as defined in RFC 44...
int mbedtls_ecp_gen_keypair_base(mbedtls_ecp_group *grp, const mbedtls_ecp_point *G, mbedtls_mpi *d, mbedtls_ecp_point *Q, int(*f_rng)(void *, unsigned char *, size_t), void *p_rng)
This function generates a keypair with a configurable base point.
#define P(row, col)
mbedtls_mpi d
Definition: ecp.h:400
unsigned int h
Definition: ecp.h:246
int mbedtls_ecp_point_cmp(const mbedtls_ecp_point *P, const mbedtls_ecp_point *Q)
This function compares two points.
int mbedtls_ecp_tls_write_point(const mbedtls_ecp_group *grp, const mbedtls_ecp_point *pt, int format, size_t *olen, unsigned char *buf, size_t blen)
This function exports a point as a TLS ECPoint record defined in RFC 4492, Section 5....
size_t T_size
Definition: ecp.h:253
mbedtls_ecp_point * T
Definition: ecp.h:252
mbedtls_ecp_point G
Definition: ecp.h:240
MPI structure.
Definition: bignum.h:210
GLenum GLenum dst
Definition: glext.h:6340
struct mbedtls_ecp_point mbedtls_ecp_point
The ECP point structure, in Jacobian coordinates.
GLint GLint GLint GLint GLint GLint y
Definition: gl.h:1548
The ECP point structure, in Jacobian coordinates.
Definition: ecp.h:149
Definition: name.c:38
const mbedtls_ecp_curve_info * mbedtls_ecp_curve_info_from_name(const char *name)
This function retrieves curve information from a human-readable name.
const mbedtls_ecp_curve_info * mbedtls_ecp_curve_list(void)
This function retrieves the information defined in mbedtls_ecp_curve_info() for all supported curves ...
const char * name
Definition: ecp.h:135
int(* t_pre)(mbedtls_ecp_point *, void *)
Definition: ecp.h:249
int mbedtls_ecp_group_load(mbedtls_ecp_group *grp, mbedtls_ecp_group_id id)
This function sets up an ECP group context from a standardized set of domain parameters.
uint16_t bit_size
Definition: ecp.h:134
#define d
Definition: ke_i.h:81
mbedtls_mpi B
Definition: ecp.h:238
Definition: path.c:41
void mbedtls_ecp_group_init(mbedtls_ecp_group *grp)
This function initializes an ECP group context without loading any domain parameters.
unsigned int(__cdecl typeof(jpeg_read_scanlines))(struct jpeg_decompress_struct *
Definition: typeof.h:31