X-Git-Url: http://git.zerfleddert.de/cgi-bin/gitweb.cgi/proxmark3-svn/blobdiff_plain/39cc1c879e3d75b3cafd79e4e139a7f6673dd349..700d8687944db0a48535f818b59b6c9859952c61:/common/mbedtls/ecp.h diff --git a/common/mbedtls/ecp.h b/common/mbedtls/ecp.h new file mode 100644 index 00000000..1821a72f --- /dev/null +++ b/common/mbedtls/ecp.h @@ -0,0 +1,766 @@ +/** + * \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 + * Standards for Efficient Cryptography Group (SECG): SEC1 + * Elliptic Curve Cryptography and + * RFC-4492: Elliptic Curve Cryptography (ECC) Cipher Suites + * for Transport Layer Security (TLS). + * + * RFC-2409: The Internet Key Exchange (IKE) defines ECP + * group types. + * + */ + +/* + * Copyright (C) 2006-2018, Arm Limited (or its affiliates), All Rights Reserved + * SPDX-License-Identifier: GPL-2.0 + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License as published by + * the Free Software Foundation; either version 2 of the License, or + * (at your option) any later version. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + * + * You should have received a copy of the GNU General Public License along + * with this program; if not, write to the Free Software Foundation, Inc., + * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA. + * + * 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: Z == 0 or + * Z == 1. Other values of \p Z are + * used only by internal functions. + * The point is zero, or "at infinity", if Z == 0. + * 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: + * + * 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 (A + 2) / 4, + * 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 0..2^(2*pbits)-1, 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: (A + 2) / 4. */ + 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 RFC-4492: Elliptic Curve Cryptography + * (ECC) Cipher Suites for Transport Layer Security (TLS), + * 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 */