| /** |
| * \file ecp.h |
| * |
| * \brief This file provides an API for Elliptic Curves over GF(P) (ECP). |
| * |
| * The use of ECP in cryptography and TLS is defined in |
| * <em>Standards for Efficient Cryptography Group (SECG): SEC1 |
| * Elliptic Curve Cryptography</em> and |
| * <em>RFC-4492: Elliptic Curve Cryptography (ECC) Cipher Suites |
| * for Transport Layer Security (TLS)</em>. |
| * |
| * <em>RFC-2409: The Internet Key Exchange (IKE)</em> defines ECP |
| * group types. |
| * |
| */ |
| |
| /* |
| * Copyright (C) 2006-2018, Arm Limited (or its affiliates), All Rights Reserved |
| * SPDX-License-Identifier: Apache-2.0 |
| * |
| * Licensed under the Apache License, Version 2.0 (the "License"); you may |
| * not use this file except in compliance with the License. |
| * You may obtain a copy of the License at |
| * |
| * http://www.apache.org/licenses/LICENSE-2.0 |
| * |
| * Unless required by applicable law or agreed to in writing, software |
| * distributed under the License is distributed on an "AS IS" BASIS, WITHOUT |
| * WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. |
| * See the License for the specific language governing permissions and |
| * limitations under the License. |
| * |
| * This file is part of Mbed TLS (https://tls.mbed.org) |
| */ |
| |
| #ifndef MBEDTLS_ECP_H |
| #define MBEDTLS_ECP_H |
| |
| #include "bignum.h" |
| |
| /* |
| * ECP error codes |
| */ |
| #define MBEDTLS_ERR_ECP_BAD_INPUT_DATA -0x4F80 /**< Bad input parameters to function. */ |
| #define MBEDTLS_ERR_ECP_BUFFER_TOO_SMALL -0x4F00 /**< The buffer is too small to write to. */ |
| #define MBEDTLS_ERR_ECP_FEATURE_UNAVAILABLE -0x4E80 /**< The requested feature is not available, for example, the requested curve is not supported. */ |
| #define MBEDTLS_ERR_ECP_VERIFY_FAILED -0x4E00 /**< The signature is not valid. */ |
| #define MBEDTLS_ERR_ECP_ALLOC_FAILED -0x4D80 /**< Memory allocation failed. */ |
| #define MBEDTLS_ERR_ECP_RANDOM_FAILED -0x4D00 /**< Generation of random value, such as ephemeral key, failed. */ |
| #define MBEDTLS_ERR_ECP_INVALID_KEY -0x4C80 /**< Invalid private or public key. */ |
| #define MBEDTLS_ERR_ECP_SIG_LEN_MISMATCH -0x4C00 /**< The buffer contains a valid signature followed by more data. */ |
| #define MBEDTLS_ERR_ECP_HW_ACCEL_FAILED -0x4B80 /**< The ECP hardware accelerator failed. */ |
| |
| #ifdef __cplusplus |
| extern "C" { |
| #endif |
| |
| /** |
| * Domain-parameter identifiers: curve, subgroup, and generator. |
| * |
| * \note Only curves over prime fields are supported. |
| * |
| * \warning This library does not support validation of arbitrary domain |
| * parameters. Therefore, only standardized domain parameters from trusted |
| * sources should be used. See mbedtls_ecp_group_load(). |
| */ |
| typedef enum |
| { |
| MBEDTLS_ECP_DP_NONE = 0, /*!< Curve not defined. */ |
| MBEDTLS_ECP_DP_SECP192R1, /*!< Domain parameters for the 192-bit curve defined by FIPS 186-4 and SEC1. */ |
| MBEDTLS_ECP_DP_SECP224R1, /*!< Domain parameters for the 224-bit curve defined by FIPS 186-4 and SEC1. */ |
| MBEDTLS_ECP_DP_SECP256R1, /*!< Domain parameters for the 256-bit curve defined by FIPS 186-4 and SEC1. */ |
| MBEDTLS_ECP_DP_SECP384R1, /*!< Domain parameters for the 384-bit curve defined by FIPS 186-4 and SEC1. */ |
| MBEDTLS_ECP_DP_SECP521R1, /*!< Domain parameters for the 521-bit curve defined by FIPS 186-4 and SEC1. */ |
| MBEDTLS_ECP_DP_BP256R1, /*!< Domain parameters for 256-bit Brainpool curve. */ |
| MBEDTLS_ECP_DP_BP384R1, /*!< Domain parameters for 384-bit Brainpool curve. */ |
| MBEDTLS_ECP_DP_BP512R1, /*!< Domain parameters for 512-bit Brainpool curve. */ |
| MBEDTLS_ECP_DP_CURVE25519, /*!< Domain parameters for Curve25519. */ |
| MBEDTLS_ECP_DP_SECP192K1, /*!< Domain parameters for 192-bit "Koblitz" curve. */ |
| MBEDTLS_ECP_DP_SECP224K1, /*!< Domain parameters for 224-bit "Koblitz" curve. */ |
| MBEDTLS_ECP_DP_SECP256K1, /*!< Domain parameters for 256-bit "Koblitz" curve. */ |
| MBEDTLS_ECP_DP_CURVE448, /*!< Domain parameters for Curve448. */ |
| } mbedtls_ecp_group_id; |
| |
| /** |
| * The number of supported curves, plus one for #MBEDTLS_ECP_DP_NONE. |
| * |
| * \note Montgomery curves are currently excluded. |
| */ |
| #define MBEDTLS_ECP_DP_MAX 12 |
| |
| /** |
| * Curve information, for use by other modules. |
| */ |
| typedef struct mbedtls_ecp_curve_info |
| { |
| mbedtls_ecp_group_id grp_id; /*!< An internal identifier. */ |
| uint16_t tls_id; /*!< The TLS NamedCurve identifier. */ |
| uint16_t bit_size; /*!< The curve size in bits. */ |
| const char *name; /*!< A human-friendly name. */ |
| } mbedtls_ecp_curve_info; |
| |
| /** |
| * \brief The ECP point structure, in Jacobian coordinates. |
| * |
| * \note All functions expect and return points satisfying |
| * the following condition: <code>Z == 0</code> or |
| * <code>Z == 1</code>. Other values of \p Z are |
| * used only by internal functions. |
| * The point is zero, or "at infinity", if <code>Z == 0</code>. |
| * Otherwise, \p X and \p Y are its standard (affine) |
| * coordinates. |
| */ |
| typedef struct mbedtls_ecp_point |
| { |
| mbedtls_mpi X; /*!< The X coordinate of the ECP point. */ |
| mbedtls_mpi Y; /*!< The Y coordinate of the ECP point. */ |
| mbedtls_mpi Z; /*!< The Z coordinate of the ECP point. */ |
| } |
| mbedtls_ecp_point; |
| |
| #if !defined(MBEDTLS_ECP_ALT) |
| /* |
| * default mbed TLS elliptic curve arithmetic implementation |
| * |
| * (in case MBEDTLS_ECP_ALT is defined then the developer has to provide an |
| * alternative implementation for the whole module and it will replace this |
| * one.) |
| */ |
| |
| /** |
| * \brief The ECP group structure. |
| * |
| * We consider two types of curve equations: |
| * <ul><li>Short Weierstrass: <code>y^2 = x^3 + A x + B mod P</code> |
| * (SEC1 + RFC-4492)</li> |
| * <li>Montgomery: <code>y^2 = x^3 + A x^2 + x mod P</code> (Curve25519, |
| * Curve448)</li></ul> |
| * In both cases, the generator (\p G) for a prime-order subgroup is fixed. |
| * |
| * For Short Weierstrass, this subgroup is the whole curve, and its |
| * cardinality is denoted by \p N. Our code requires that \p N is an |
| * odd prime as mbedtls_ecp_mul() requires an odd number, and |
| * mbedtls_ecdsa_sign() requires that it is prime for blinding purposes. |
| * |
| * For Montgomery curves, we do not store \p A, but <code>(A + 2) / 4</code>, |
| * which is the quantity used in the formulas. Additionally, \p nbits is |
| * not the size of \p N but the required size for private keys. |
| * |
| * If \p modp is NULL, reduction modulo \p P is done using a generic algorithm. |
| * Otherwise, \p modp must point to a function that takes an \p mbedtls_mpi in the |
| * range of <code>0..2^(2*pbits)-1</code>, and transforms it in-place to an integer |
| * which is congruent mod \p P to the given MPI, and is close enough to \p pbits |
| * in size, so that it may be efficiently brought in the 0..P-1 range by a few |
| * additions or subtractions. Therefore, it is only an approximative modular |
| * reduction. It must return 0 on success and non-zero on failure. |
| * |
| */ |
| typedef struct mbedtls_ecp_group |
| { |
| mbedtls_ecp_group_id id; /*!< An internal group identifier. */ |
| mbedtls_mpi P; /*!< The prime modulus of the base field. */ |
| mbedtls_mpi A; /*!< For Short Weierstrass: \p A in the equation. For |
| Montgomery curves: <code>(A + 2) / 4</code>. */ |
| mbedtls_mpi B; /*!< For Short Weierstrass: \p B in the equation. |
| For Montgomery curves: unused. */ |
| mbedtls_ecp_point G; /*!< The generator of the subgroup used. */ |
| mbedtls_mpi N; /*!< The order of \p G. */ |
| size_t pbits; /*!< The number of bits in \p P.*/ |
| size_t nbits; /*!< For Short Weierstrass: The number of bits in \p P. |
| For Montgomery curves: the number of bits in the |
| private keys. */ |
| unsigned int h; /*!< \internal 1 if the constants are static. */ |
| int (*modp)(mbedtls_mpi *); /*!< The function for fast pseudo-reduction |
| mod \p P (see above).*/ |
| int (*t_pre)(mbedtls_ecp_point *, void *); /*!< Unused. */ |
| int (*t_post)(mbedtls_ecp_point *, void *); /*!< Unused. */ |
| void *t_data; /*!< Unused. */ |
| mbedtls_ecp_point *T; /*!< Pre-computed points for ecp_mul_comb(). */ |
| size_t T_size; /*!< The number of pre-computed points. */ |
| } |
| mbedtls_ecp_group; |
| |
| /** |
| * \name SECTION: Module settings |
| * |
| * The configuration options you can set for this module are in this section. |
| * Either change them in config.h, or define them using the compiler command line. |
| * \{ |
| */ |
| |
| #if !defined(MBEDTLS_ECP_MAX_BITS) |
| /** |
| * The maximum size of the groups, that is, of \c N and \c P. |
| */ |
| #define MBEDTLS_ECP_MAX_BITS 521 /**< The maximum size of groups, in bits. */ |
| #endif |
| |
| #define MBEDTLS_ECP_MAX_BYTES ( ( MBEDTLS_ECP_MAX_BITS + 7 ) / 8 ) |
| #define MBEDTLS_ECP_MAX_PT_LEN ( 2 * MBEDTLS_ECP_MAX_BYTES + 1 ) |
| |
| #if !defined(MBEDTLS_ECP_WINDOW_SIZE) |
| /* |
| * Maximum "window" size used for point multiplication. |
| * Default: 6. |
| * Minimum value: 2. Maximum value: 7. |
| * |
| * Result is an array of at most ( 1 << ( MBEDTLS_ECP_WINDOW_SIZE - 1 ) ) |
| * points used for point multiplication. This value is directly tied to EC |
| * peak memory usage, so decreasing it by one should roughly cut memory usage |
| * by two (if large curves are in use). |
| * |
| * Reduction in size may reduce speed, but larger curves are impacted first. |
| * Sample performances (in ECDHE handshakes/s, with FIXED_POINT_OPTIM = 1): |
| * w-size: 6 5 4 3 2 |
| * 521 145 141 135 120 97 |
| * 384 214 209 198 177 146 |
| * 256 320 320 303 262 226 |
| * 224 475 475 453 398 342 |
| * 192 640 640 633 587 476 |
| */ |
| #define MBEDTLS_ECP_WINDOW_SIZE 6 /**< The maximum window size used. */ |
| #endif /* MBEDTLS_ECP_WINDOW_SIZE */ |
| |
| #if !defined(MBEDTLS_ECP_FIXED_POINT_OPTIM) |
| /* |
| * Trade memory for speed on fixed-point multiplication. |
| * |
| * This speeds up repeated multiplication of the generator (that is, the |
| * multiplication in ECDSA signatures, and half of the multiplications in |
| * ECDSA verification and ECDHE) by a factor roughly 3 to 4. |
| * |
| * The cost is increasing EC peak memory usage by a factor roughly 2. |
| * |
| * Change this value to 0 to reduce peak memory usage. |
| */ |
| #define MBEDTLS_ECP_FIXED_POINT_OPTIM 1 /**< Enable fixed-point speed-up. */ |
| #endif /* MBEDTLS_ECP_FIXED_POINT_OPTIM */ |
| |
| /* \} name SECTION: Module settings */ |
| |
| #else /* MBEDTLS_ECP_ALT */ |
| #include "ecp_alt.h" |
| #endif /* MBEDTLS_ECP_ALT */ |
| |
| /** |
| * \brief The ECP key-pair structure. |
| * |
| * A generic key-pair that may be used for ECDSA and fixed ECDH, for example. |
| * |
| * \note Members are deliberately in the same order as in the |
| * ::mbedtls_ecdsa_context structure. |
| */ |
| typedef struct mbedtls_ecp_keypair |
| { |
| mbedtls_ecp_group grp; /*!< Elliptic curve and base point */ |
| mbedtls_mpi d; /*!< our secret value */ |
| mbedtls_ecp_point Q; /*!< our public value */ |
| } |
| mbedtls_ecp_keypair; |
| |
| /* |
| * Point formats, from RFC 4492's enum ECPointFormat |
| */ |
| #define MBEDTLS_ECP_PF_UNCOMPRESSED 0 /**< Uncompressed point format. */ |
| #define MBEDTLS_ECP_PF_COMPRESSED 1 /**< Compressed point format. */ |
| |
| /* |
| * Some other constants from RFC 4492 |
| */ |
| #define MBEDTLS_ECP_TLS_NAMED_CURVE 3 /**< The named_curve of ECCurveType. */ |
| |
| /** |
| * \brief This function retrieves the information defined in |
| * mbedtls_ecp_curve_info() for all supported curves in order |
| * of preference. |
| * |
| * \return A statically allocated array. The last entry is 0. |
| */ |
| const mbedtls_ecp_curve_info *mbedtls_ecp_curve_list( void ); |
| |
| /** |
| * \brief This function retrieves the list of internal group |
| * identifiers of all supported curves in the order of |
| * preference. |
| * |
| * \return A statically allocated array, |
| * terminated with MBEDTLS_ECP_DP_NONE. |
| */ |
| const mbedtls_ecp_group_id *mbedtls_ecp_grp_id_list( void ); |
| |
| /** |
| * \brief This function retrieves curve information from an internal |
| * group identifier. |
| * |
| * \param grp_id An \c MBEDTLS_ECP_DP_XXX value. |
| * |
| * \return The associated curve information on success. |
| * \return NULL on failure. |
| */ |
| const mbedtls_ecp_curve_info *mbedtls_ecp_curve_info_from_grp_id( mbedtls_ecp_group_id grp_id ); |
| |
| /** |
| * \brief This function retrieves curve information from a TLS |
| * NamedCurve value. |
| * |
| * \param tls_id An \c MBEDTLS_ECP_DP_XXX value. |
| * |
| * \return The associated curve information on success. |
| * \return NULL on failure. |
| */ |
| const mbedtls_ecp_curve_info *mbedtls_ecp_curve_info_from_tls_id( uint16_t tls_id ); |
| |
| /** |
| * \brief This function retrieves curve information from a |
| * human-readable name. |
| * |
| * \param name The human-readable name. |
| * |
| * \return The associated curve information on success. |
| * \return NULL on failure. |
| */ |
| const mbedtls_ecp_curve_info *mbedtls_ecp_curve_info_from_name( const char *name ); |
| |
| /** |
| * \brief This function initializes a point as zero. |
| * |
| * \param pt The point to initialize. |
| */ |
| void mbedtls_ecp_point_init( mbedtls_ecp_point *pt ); |
| |
| /** |
| * \brief This function initializes an ECP group context |
| * without loading any domain parameters. |
| * |
| * \note After this function is called, domain parameters |
| * for various ECP groups can be loaded through the |
| * mbedtls_ecp_load() or mbedtls_ecp_tls_read_group() |
| * functions. |
| */ |
| void mbedtls_ecp_group_init( mbedtls_ecp_group *grp ); |
| |
| /** |
| * \brief This function initializes a key pair as an invalid one. |
| * |
| * \param key The key pair to initialize. |
| */ |
| void mbedtls_ecp_keypair_init( mbedtls_ecp_keypair *key ); |
| |
| /** |
| * \brief This function frees the components of a point. |
| * |
| * \param pt The point to free. |
| */ |
| void mbedtls_ecp_point_free( mbedtls_ecp_point *pt ); |
| |
| /** |
| * \brief This function frees the components of an ECP group. |
| * \param grp The group to free. |
| */ |
| void mbedtls_ecp_group_free( mbedtls_ecp_group *grp ); |
| |
| /** |
| * \brief This function frees the components of a key pair. |
| * \param key The key pair to free. |
| */ |
| void mbedtls_ecp_keypair_free( mbedtls_ecp_keypair *key ); |
| |
| /** |
| * \brief This function copies the contents of point \p Q into |
| * point \p P. |
| * |
| * \param P The destination point. |
| * \param Q The source point. |
| * |
| * \return \c 0 on success. |
| * \return #MBEDTLS_ERR_MPI_ALLOC_FAILED on memory-allocation failure. |
| */ |
| int mbedtls_ecp_copy( mbedtls_ecp_point *P, const mbedtls_ecp_point *Q ); |
| |
| /** |
| * \brief This function copies the contents of group \p src into |
| * group \p dst. |
| * |
| * \param dst The destination group. |
| * \param src The source group. |
| * |
| * \return \c 0 on success. |
| * \return #MBEDTLS_ERR_MPI_ALLOC_FAILED on memory-allocation failure. |
| */ |
| int mbedtls_ecp_group_copy( mbedtls_ecp_group *dst, const mbedtls_ecp_group *src ); |
| |
| /** |
| * \brief This function sets a point to zero. |
| * |
| * \param pt The point to set. |
| * |
| * \return \c 0 on success. |
| * \return #MBEDTLS_ERR_MPI_ALLOC_FAILED on memory-allocation failure. |
| */ |
| int mbedtls_ecp_set_zero( mbedtls_ecp_point *pt ); |
| |
| /** |
| * \brief This function checks if a point is zero. |
| * |
| * \param pt The point to test. |
| * |
| * \return \c 1 if the point is zero. |
| * \return \c 0 if the point is non-zero. |
| */ |
| int mbedtls_ecp_is_zero( mbedtls_ecp_point *pt ); |
| |
| /** |
| * \brief This function compares two points. |
| * |
| * \note This assumes that the points are normalized. Otherwise, |
| * they may compare as "not equal" even if they are. |
| * |
| * \param P The first point to compare. |
| * \param Q The second point to compare. |
| * |
| * \return \c 0 if the points are equal. |
| * \return #MBEDTLS_ERR_ECP_BAD_INPUT_DATA if the points are not equal. |
| */ |
| int mbedtls_ecp_point_cmp( const mbedtls_ecp_point *P, |
| const mbedtls_ecp_point *Q ); |
| |
| /** |
| * \brief This function imports a non-zero point from two ASCII |
| * strings. |
| * |
| * \param P The destination point. |
| * \param radix The numeric base of the input. |
| * \param x The first affine coordinate, as a null-terminated string. |
| * \param y The second affine coordinate, as a null-terminated string. |
| * |
| * \return \c 0 on success. |
| * \return An \c MBEDTLS_ERR_MPI_XXX error code on failure. |
| */ |
| int mbedtls_ecp_point_read_string( mbedtls_ecp_point *P, int radix, |
| const char *x, const char *y ); |
| |
| /** |
| * \brief This function exports a point into unsigned binary data. |
| * |
| * \param grp The group to which the point should belong. |
| * \param P The point to export. |
| * \param format The point format. Should be an \c MBEDTLS_ECP_PF_XXX macro. |
| * \param olen The length of the output. |
| * \param buf The output buffer. |
| * \param buflen The length of the output buffer. |
| * |
| * \return \c 0 on success. |
| * \return #MBEDTLS_ERR_ECP_BAD_INPUT_DATA |
| * or #MBEDTLS_ERR_ECP_BUFFER_TOO_SMALL on failure. |
| */ |
| 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 ); |
| |
| /** |
| * \brief This function imports a point from unsigned binary data. |
| * |
| * \note This function does not check that the point actually |
| * belongs to the given group, see mbedtls_ecp_check_pubkey() |
| * for that. |
| * |
| * \param grp The group to which the point should belong. |
| * \param P The point to import. |
| * \param buf The input buffer. |
| * \param ilen The length of the input. |
| * |
| * \return \c 0 on success. |
| * \return #MBEDTLS_ERR_ECP_BAD_INPUT_DATA if input is invalid. |
| * \return #MBEDTLS_ERR_MPI_ALLOC_FAILED on memory-allocation failure. |
| * \return #MBEDTLS_ERR_ECP_FEATURE_UNAVAILABLE if the point format |
| * is not implemented. |
| * |
| */ |
| int mbedtls_ecp_point_read_binary( const mbedtls_ecp_group *grp, mbedtls_ecp_point *P, |
| const unsigned char *buf, size_t ilen ); |
| |
| /** |
| * \brief This function imports a point from a TLS ECPoint record. |
| * |
| * \note On function return, \p buf is updated to point to immediately |
| * after the ECPoint record. |
| * |
| * \param grp The ECP group used. |
| * \param pt The destination point. |
| * \param buf The address of the pointer to the start of the input buffer. |
| * \param len The length of the buffer. |
| * |
| * \return \c 0 on success. |
| * \return An \c MBEDTLS_ERR_MPI_XXX error code on initialization failure. |
| * \return #MBEDTLS_ERR_ECP_BAD_INPUT_DATA if input is invalid. |
| */ |
| int mbedtls_ecp_tls_read_point( const mbedtls_ecp_group *grp, mbedtls_ecp_point *pt, |
| const unsigned char **buf, size_t len ); |
| |
| /** |
| * \brief This function exports a point as a TLS ECPoint record. |
| * |
| * \param grp The ECP group used. |
| * \param pt The point format to export to. The point format is an |
| * \c MBEDTLS_ECP_PF_XXX constant. |
| * \param format The export format. |
| * \param olen The length of the data written. |
| * \param buf The buffer to write to. |
| * \param blen The length of the buffer. |
| * |
| * \return \c 0 on success. |
| * \return #MBEDTLS_ERR_ECP_BAD_INPUT_DATA or |
| * #MBEDTLS_ERR_ECP_BUFFER_TOO_SMALL on failure. |
| */ |
| 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 ); |
| |
| /** |
| * \brief This function sets a group using standardized domain parameters. |
| * |
| * \note The index should be a value of the NamedCurve enum, |
| * as defined in <em>RFC-4492: Elliptic Curve Cryptography |
| * (ECC) Cipher Suites for Transport Layer Security (TLS)</em>, |
| * usually in the form of an \c MBEDTLS_ECP_DP_XXX macro. |
| * |
| * \param grp The destination group. |
| * \param id The identifier of the domain parameter set to load. |
| * |
| * \return \c 0 on success, |
| * \return An \c MBEDTLS_ERR_MPI_XXX error code on initialization failure. |
| * \return #MBEDTLS_ERR_ECP_FEATURE_UNAVAILABLE for unkownn groups. |
| |
| */ |
| int mbedtls_ecp_group_load( mbedtls_ecp_group *grp, mbedtls_ecp_group_id id ); |
| |
| /** |
| * \brief This function sets a group from a TLS ECParameters record. |
| * |
| * \note \p buf is updated to point right after the ECParameters record |
| * on exit. |
| * |
| * \param grp The destination group. |
| * \param buf The address of the pointer to the start of the input buffer. |
| * \param len The length of the buffer. |
| * |
| * \return \c 0 on success. |
| * \return An \c MBEDTLS_ERR_MPI_XXX error code on initialization failure. |
| * \return #MBEDTLS_ERR_ECP_BAD_INPUT_DATA if input is invalid. |
| */ |
| int mbedtls_ecp_tls_read_group( mbedtls_ecp_group *grp, const unsigned char **buf, size_t len ); |
| |
| /** |
| * \brief This function writes the TLS ECParameters record for a group. |
| * |
| * \param grp The ECP group used. |
| * \param olen The number of Bytes written. |
| * \param buf The buffer to write to. |
| * \param blen The length of the buffer. |
| * |
| * \return \c 0 on success. |
| * \return #MBEDTLS_ERR_ECP_BUFFER_TOO_SMALL on failure. |
| */ |
| int mbedtls_ecp_tls_write_group( const mbedtls_ecp_group *grp, size_t *olen, |
| unsigned char *buf, size_t blen ); |
| |
| /** |
| * \brief This function performs multiplication of a point by |
| * an integer: \p R = \p m * \p P. |
| * |
| * It is not thread-safe to use same group in multiple threads. |
| * |
| * \note To prevent timing attacks, this function |
| * executes the exact same sequence of base-field |
| * operations for any valid \p m. It avoids any if-branch or |
| * array index depending on the value of \p m. |
| * |
| * \note If \p f_rng is not NULL, it is used to randomize |
| * intermediate results to prevent potential timing attacks |
| * targeting these results. We recommend always providing |
| * a non-NULL \p f_rng. The overhead is negligible. |
| * |
| * \param grp The ECP group. |
| * \param R The destination point. |
| * \param m The integer by which to multiply. |
| * \param P The point to multiply. |
| * \param f_rng The RNG function. |
| * \param p_rng The RNG context. |
| * |
| * \return \c 0 on success. |
| * \return #MBEDTLS_ERR_ECP_INVALID_KEY if \p m is not a valid private |
| * key, or \p P is not a valid public key. |
| * \return #MBEDTLS_ERR_MPI_ALLOC_FAILED on memory-allocation failure. |
| */ |
| 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 ); |
| |
| /** |
| * \brief This function performs multiplication and addition of two |
| * points by integers: \p R = \p m * \p P + \p n * \p Q |
| * |
| * It is not thread-safe to use same group in multiple threads. |
| * |
| * \note In contrast to mbedtls_ecp_mul(), this function does not |
| * guarantee a constant execution flow and timing. |
| * |
| * \param grp The ECP group. |
| * \param R The destination point. |
| * \param m The integer by which to multiply \p P. |
| * \param P The point to multiply by \p m. |
| * \param n The integer by which to multiply \p Q. |
| * \param Q The point to be multiplied by \p n. |
| * |
| * \return \c 0 on success. |
| * \return #MBEDTLS_ERR_ECP_INVALID_KEY if \p m or \p n are not |
| * valid private keys, or \p P or \p Q are not valid public |
| * keys. |
| * \return #MBEDTLS_ERR_MPI_ALLOC_FAILED on memory-allocation failure. |
| */ |
| 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 ); |
| |
| /** |
| * \brief This function checks that a point is a valid public key |
| * on this curve. |
| * |
| * It only checks that the point is non-zero, has |
| * valid coordinates and lies on the curve. It does not verify |
| * that it is indeed a multiple of \p G. This additional |
| * check is computationally more expensive, is not required |
| * by standards, and should not be necessary if the group |
| * used has a small cofactor. In particular, it is useless for |
| * the NIST groups which all have a cofactor of 1. |
| * |
| * \note This function uses bare components rather than an |
| * ::mbedtls_ecp_keypair structure, to ease use with other |
| * structures, such as ::mbedtls_ecdh_context or |
| * ::mbedtls_ecdsa_context. |
| * |
| * \param grp The curve the point should lie on. |
| * \param pt The point to check. |
| * |
| * \return \c 0 if the point is a valid public key. |
| * \return #MBEDTLS_ERR_ECP_INVALID_KEY on failure. |
| */ |
| int mbedtls_ecp_check_pubkey( const mbedtls_ecp_group *grp, const mbedtls_ecp_point *pt ); |
| |
| /** |
| * \brief This function checks that an \p mbedtls_mpi is a valid private |
| * key for this curve. |
| * |
| * \note This function uses bare components rather than an |
| * ::mbedtls_ecp_keypair structure to ease use with other |
| * structures, such as ::mbedtls_ecdh_context or |
| * ::mbedtls_ecdsa_context. |
| * |
| * \param grp The group used. |
| * \param d The integer to check. |
| * |
| * \return \c 0 if the point is a valid private key. |
| * \return #MBEDTLS_ERR_ECP_INVALID_KEY on failure. |
| */ |
| int mbedtls_ecp_check_privkey( const mbedtls_ecp_group *grp, const mbedtls_mpi *d ); |
| |
| /** |
| * \brief This function generates a keypair with a configurable base |
| * point. |
| * |
| * \note This function uses bare components rather than an |
| * ::mbedtls_ecp_keypair structure to ease use with other |
| * structures, such as ::mbedtls_ecdh_context or |
| * ::mbedtls_ecdsa_context. |
| * |
| * \param grp The ECP group. |
| * \param G The chosen base point. |
| * \param d The destination MPI (secret part). |
| * \param Q The destination point (public part). |
| * \param f_rng The RNG function. |
| * \param p_rng The RNG context. |
| * |
| * \return \c 0 on success. |
| * \return An \c MBEDTLS_ERR_ECP_XXX or \c MBEDTLS_MPI_XXX error code |
| * on failure. |
| */ |
| 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 ); |
| |
| /** |
| * \brief This function generates an ECP keypair. |
| * |
| * \note This function uses bare components rather than an |
| * ::mbedtls_ecp_keypair structure to ease use with other |
| * structures, such as ::mbedtls_ecdh_context or |
| * ::mbedtls_ecdsa_context. |
| * |
| * \param grp The ECP group. |
| * \param d The destination MPI (secret part). |
| * \param Q The destination point (public part). |
| * \param f_rng The RNG function. |
| * \param p_rng The RNG context. |
| * |
| * \return \c 0 on success. |
| * \return An \c MBEDTLS_ERR_ECP_XXX or \c MBEDTLS_MPI_XXX error code |
| * on failure. |
| */ |
| 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 ); |
| |
| /** |
| * \brief This function generates an ECP key. |
| * |
| * \param grp_id The ECP group identifier. |
| * \param key The destination key. |
| * \param f_rng The RNG function. |
| * \param p_rng The RNG context. |
| * |
| * \return \c 0 on success. |
| * \return An \c MBEDTLS_ERR_ECP_XXX or \c MBEDTLS_MPI_XXX error code |
| * on failure. |
| */ |
| 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 ); |
| |
| /** |
| * \brief This function checks that the keypair objects |
| * \p pub and \p prv have the same group and the |
| * same public point, and that the private key in |
| * \p prv is consistent with the public key. |
| * |
| * \param pub The keypair structure holding the public key. |
| * If it contains a private key, that part is ignored. |
| * \param prv The keypair structure holding the full keypair. |
| * |
| * \return \c 0 on success, meaning that the keys are valid and match. |
| * \return #MBEDTLS_ERR_ECP_BAD_INPUT_DATA if the keys are invalid or do not match. |
| * \return An \c MBEDTLS_ERR_ECP_XXX or an \c MBEDTLS_ERR_MPI_XXX |
| * error code on calculation failure. |
| */ |
| int mbedtls_ecp_check_pub_priv( const mbedtls_ecp_keypair *pub, const mbedtls_ecp_keypair *prv ); |
| |
| #if defined(MBEDTLS_SELF_TEST) |
| |
| /** |
| * \brief The ECP checkup routine. |
| * |
| * \return \c 0 on success. |
| * \return \c 1 on failure. |
| */ |
| int mbedtls_ecp_self_test( int verbose ); |
| |
| #endif /* MBEDTLS_SELF_TEST */ |
| |
| #ifdef __cplusplus |
| } |
| #endif |
| |
| #endif /* ecp.h */ |
