| /** |
| * \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 The Mbed TLS Contributors |
| * SPDX-License-Identifier: Apache-2.0 OR GPL-2.0-or-later |
| */ |
| |
| #ifndef MBEDTLS_ECP_H |
| #define MBEDTLS_ECP_H |
| |
| #if !defined(MBEDTLS_CONFIG_FILE) |
| #include "mbedtls/config.h" |
| #else |
| #include MBEDTLS_CONFIG_FILE |
| #endif |
| |
| #include "mbedtls/bignum.h" |
| |
| #if (defined(__ARMCC_VERSION) || defined(_MSC_VER)) && \ |
| !defined(inline) && !defined(__cplusplus) |
| #define inline __inline |
| #endif |
| |
| /* |
| * ECP error codes |
| */ |
| /** Bad input parameters to function. */ |
| #define MBEDTLS_ERR_ECP_BAD_INPUT_DATA -0x4F80 |
| /** The buffer is too small to write to. */ |
| #define MBEDTLS_ERR_ECP_BUFFER_TOO_SMALL -0x4F00 |
| /** The requested feature is not available, for example, the requested curve is not supported. */ |
| #define MBEDTLS_ERR_ECP_FEATURE_UNAVAILABLE -0x4E80 |
| /** The signature is not valid. */ |
| #define MBEDTLS_ERR_ECP_VERIFY_FAILED -0x4E00 |
| /** Memory allocation failed. */ |
| #define MBEDTLS_ERR_ECP_ALLOC_FAILED -0x4D80 |
| /** Generation of random value, such as ephemeral key, failed. */ |
| #define MBEDTLS_ERR_ECP_RANDOM_FAILED -0x4D00 |
| /** Invalid private or public key. */ |
| #define MBEDTLS_ERR_ECP_INVALID_KEY -0x4C80 |
| /** The buffer contains a valid signature followed by more data. */ |
| #define MBEDTLS_ERR_ECP_SIG_LEN_MISMATCH -0x4C00 |
| |
| /* MBEDTLS_ERR_ECP_HW_ACCEL_FAILED is deprecated and should not be used. */ |
| /** The ECP hardware accelerator failed. */ |
| #define MBEDTLS_ERR_ECP_HW_ACCEL_FAILED -0x4B80 |
| |
| /** Operation in progress, call again with the same parameters to continue. */ |
| #define MBEDTLS_ERR_ECP_IN_PROGRESS -0x4B00 |
| |
| /* Flags indicating whether to include code that is specific to certain |
| * types of curves. These flags are for internal library use only. */ |
| #if defined(MBEDTLS_ECP_DP_SECP192R1_ENABLED) || \ |
| defined(MBEDTLS_ECP_DP_SECP224R1_ENABLED) || \ |
| defined(MBEDTLS_ECP_DP_SECP256R1_ENABLED) || \ |
| defined(MBEDTLS_ECP_DP_SECP384R1_ENABLED) || \ |
| defined(MBEDTLS_ECP_DP_SECP521R1_ENABLED) || \ |
| defined(MBEDTLS_ECP_DP_BP256R1_ENABLED) || \ |
| defined(MBEDTLS_ECP_DP_BP384R1_ENABLED) || \ |
| defined(MBEDTLS_ECP_DP_BP512R1_ENABLED) || \ |
| defined(MBEDTLS_ECP_DP_SECP192K1_ENABLED) || \ |
| defined(MBEDTLS_ECP_DP_SECP224K1_ENABLED) || \ |
| defined(MBEDTLS_ECP_DP_SECP256K1_ENABLED) |
| #define MBEDTLS_ECP_SHORT_WEIERSTRASS_ENABLED |
| #endif |
| #if defined(MBEDTLS_ECP_DP_CURVE25519_ENABLED) || \ |
| defined(MBEDTLS_ECP_DP_CURVE448_ENABLED) |
| #define MBEDTLS_ECP_MONTGOMERY_ENABLED |
| #endif |
| |
| #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(). |
| */ |
| /* Note: when adding a new curve: |
| * - Add it at the end of this enum, otherwise you'll break the ABI by |
| * changing the numerical value for existing curves. |
| * - Increment MBEDTLS_ECP_DP_MAX below if needed. |
| * - Update the calculation of MBEDTLS_ECP_MAX_BITS_MIN below. |
| * - Add the corresponding MBEDTLS_ECP_DP_xxx_ENABLED macro definition to |
| * config.h. |
| * - List the curve as a dependency of MBEDTLS_ECP_C and |
| * MBEDTLS_ECDSA_C if supported in check_config.h. |
| * - Add the curve to the appropriate curve type macro |
| * MBEDTLS_ECP_yyy_ENABLED above. |
| * - Add the necessary definitions to ecp_curves.c. |
| * - Add the curve to the ecp_supported_curves array in ecp.c. |
| * - Add the curve to applicable profiles in x509_crt.c if applicable. |
| */ |
| 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 types |
| */ |
| typedef enum { |
| MBEDTLS_ECP_TYPE_NONE = 0, |
| MBEDTLS_ECP_TYPE_SHORT_WEIERSTRASS, /* y^2 = x^3 + a x + b */ |
| MBEDTLS_ECP_TYPE_MONTGOMERY, /* y^2 = x^3 + a x^2 + x */ |
| } mbedtls_ecp_curve_type; |
| |
| /** |
| * 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; |
| |
| /* Determine the minimum safe value of MBEDTLS_ECP_MAX_BITS. */ |
| #if !defined(MBEDTLS_ECP_C) |
| #define MBEDTLS_ECP_MAX_BITS_MIN 0 |
| /* Note: the curves must be listed in DECREASING size! */ |
| #elif defined(MBEDTLS_ECP_DP_SECP521R1_ENABLED) |
| #define MBEDTLS_ECP_MAX_BITS_MIN 521 |
| #elif defined(MBEDTLS_ECP_DP_BP512R1_ENABLED) |
| #define MBEDTLS_ECP_MAX_BITS_MIN 512 |
| #elif defined(MBEDTLS_ECP_DP_CURVE448_ENABLED) |
| #define MBEDTLS_ECP_MAX_BITS_MIN 448 |
| #elif defined(MBEDTLS_ECP_DP_BP384R1_ENABLED) |
| #define MBEDTLS_ECP_MAX_BITS_MIN 384 |
| #elif defined(MBEDTLS_ECP_DP_SECP384R1_ENABLED) |
| #define MBEDTLS_ECP_MAX_BITS_MIN 384 |
| #elif defined(MBEDTLS_ECP_DP_BP256R1_ENABLED) |
| #define MBEDTLS_ECP_MAX_BITS_MIN 256 |
| #elif defined(MBEDTLS_ECP_DP_SECP256K1_ENABLED) |
| #define MBEDTLS_ECP_MAX_BITS_MIN 256 |
| #elif defined(MBEDTLS_ECP_DP_SECP256R1_ENABLED) |
| #define MBEDTLS_ECP_MAX_BITS_MIN 256 |
| #elif defined(MBEDTLS_ECP_DP_CURVE25519_ENABLED) |
| #define MBEDTLS_ECP_MAX_BITS_MIN 255 |
| #elif defined(MBEDTLS_ECP_DP_SECP224K1_ENABLED) |
| #define MBEDTLS_ECP_MAX_BITS_MIN 225 // n is slightly above 2^224 |
| #elif defined(MBEDTLS_ECP_DP_SECP224R1_ENABLED) |
| #define MBEDTLS_ECP_MAX_BITS_MIN 224 |
| #elif defined(MBEDTLS_ECP_DP_SECP192K1_ENABLED) |
| #define MBEDTLS_ECP_MAX_BITS_MIN 192 |
| #elif defined(MBEDTLS_ECP_DP_SECP192R1_ENABLED) |
| #define MBEDTLS_ECP_MAX_BITS_MIN 192 |
| #else |
| #error "MBEDTLS_ECP_C enabled, but no curve?" |
| #endif |
| |
| #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. |
| * |
| * The default implementation only initializes \p A without setting it to the |
| * authentic value for curves with <code>A = -3</code>(SECP256R1, etc), in which |
| * case you need to load \p A by yourself when using domain parameters directly, |
| * for example: |
| * \code |
| * mbedtls_mpi_init(&A); |
| * mbedtls_ecp_group_init(&grp); |
| * CHECK_RETURN(mbedtls_ecp_group_load(&grp, grp_id)); |
| * if (mbedtls_ecp_group_a_is_minus_3(&grp)) { |
| * CHECK_RETURN(mbedtls_mpi_sub_int(&A, &grp.P, 3)); |
| * } else { |
| * CHECK_RETURN(mbedtls_mpi_copy(&A, &grp.A)); |
| * } |
| * |
| * do_something_with_a(&A); |
| * |
| * cleanup: |
| * mbedtls_mpi_free(&A); |
| * mbedtls_ecp_group_free(&grp); |
| * \endcode |
| * |
| * 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. |
| * |
| * \note Alternative implementations must keep the group IDs distinct. If |
| * two group structures have the same ID, then they must be |
| * identical. |
| * |
| */ |
| 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. Note that |
| \p A is not set to the authentic value in some cases. |
| Refer to detailed description of ::mbedtls_ecp_group if |
| using domain parameters in the structure. |
| 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) |
| |
| #if MBEDTLS_ECP_MAX_BITS < MBEDTLS_ECP_MAX_BITS_MIN |
| #error "MBEDTLS_ECP_MAX_BITS is smaller than the largest supported curve" |
| #endif |
| |
| #elif defined(MBEDTLS_ECP_C) |
| /** |
| * The maximum size of the groups, that is, of \c N and \c P. |
| */ |
| #define MBEDTLS_ECP_MAX_BITS MBEDTLS_ECP_MAX_BITS_MIN |
| |
| #else |
| /* MBEDTLS_ECP_MAX_BITS is not relevant without MBEDTLS_ECP_C, but set it |
| * to a nonzero value so that code that unconditionally allocates an array |
| * of a size based on it keeps working if built without ECC support. */ |
| #define MBEDTLS_ECP_MAX_BITS 1 |
| #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: a point where higher memory usage yields diminishing performance |
| * returns. |
| * 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 4 /**< 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 */ |
| |
| #if defined(MBEDTLS_ECP_RESTARTABLE) |
| |
| /** |
| * \brief Internal restart context for multiplication |
| * |
| * \note Opaque struct |
| */ |
| typedef struct mbedtls_ecp_restart_mul mbedtls_ecp_restart_mul_ctx; |
| |
| /** |
| * \brief Internal restart context for ecp_muladd() |
| * |
| * \note Opaque struct |
| */ |
| typedef struct mbedtls_ecp_restart_muladd mbedtls_ecp_restart_muladd_ctx; |
| |
| /** |
| * \brief General context for resuming ECC operations |
| */ |
| typedef struct { |
| unsigned ops_done; /*!< current ops count */ |
| unsigned depth; /*!< call depth (0 = top-level) */ |
| mbedtls_ecp_restart_mul_ctx *rsm; /*!< ecp_mul_comb() sub-context */ |
| mbedtls_ecp_restart_muladd_ctx *ma; /*!< ecp_muladd() sub-context */ |
| } mbedtls_ecp_restart_ctx; |
| |
| /* |
| * Operation counts for restartable functions |
| */ |
| #define MBEDTLS_ECP_OPS_CHK 3 /*!< basic ops count for ecp_check_pubkey() */ |
| #define MBEDTLS_ECP_OPS_DBL 8 /*!< basic ops count for ecp_double_jac() */ |
| #define MBEDTLS_ECP_OPS_ADD 11 /*!< basic ops count for see ecp_add_mixed() */ |
| #define MBEDTLS_ECP_OPS_INV 120 /*!< empirical equivalent for mpi_mod_inv() */ |
| |
| /** |
| * \brief Internal; for restartable functions in other modules. |
| * Check and update basic ops budget. |
| * |
| * \param grp Group structure |
| * \param rs_ctx Restart context |
| * \param ops Number of basic ops to do |
| * |
| * \return \c 0 if doing \p ops basic ops is still allowed, |
| * \return #MBEDTLS_ERR_ECP_IN_PROGRESS otherwise. |
| */ |
| int mbedtls_ecp_check_budget(const mbedtls_ecp_group *grp, |
| mbedtls_ecp_restart_ctx *rs_ctx, |
| unsigned ops); |
| |
| /* Utility macro for checking and updating ops budget */ |
| #define MBEDTLS_ECP_BUDGET(ops) \ |
| MBEDTLS_MPI_CHK(mbedtls_ecp_check_budget(grp, rs_ctx, \ |
| (unsigned) (ops))); |
| |
| #else /* MBEDTLS_ECP_RESTARTABLE */ |
| |
| #define MBEDTLS_ECP_BUDGET(ops) /* no-op; for compatibility */ |
| |
| /* We want to declare restartable versions of existing functions anyway */ |
| typedef void mbedtls_ecp_restart_ctx; |
| |
| #endif /* MBEDTLS_ECP_RESTARTABLE */ |
| |
| /** |
| * \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. */ |
| |
| #if defined(MBEDTLS_ECP_RESTARTABLE) |
| /** |
| * \brief Set the maximum number of basic operations done in a row. |
| * |
| * If more operations are needed to complete a computation, |
| * #MBEDTLS_ERR_ECP_IN_PROGRESS will be returned by the |
| * function performing the computation. It is then the |
| * caller's responsibility to either call again with the same |
| * parameters until it returns 0 or an error code; or to free |
| * the restart context if the operation is to be aborted. |
| * |
| * It is strictly required that all input parameters and the |
| * restart context be the same on successive calls for the |
| * same operation, but output parameters need not be the |
| * same; they must not be used until the function finally |
| * returns 0. |
| * |
| * This only applies to functions whose documentation |
| * mentions they may return #MBEDTLS_ERR_ECP_IN_PROGRESS (or |
| * #MBEDTLS_ERR_SSL_CRYPTO_IN_PROGRESS for functions in the |
| * SSL module). For functions that accept a "restart context" |
| * argument, passing NULL disables restart and makes the |
| * function equivalent to the function with the same name |
| * with \c _restartable removed. For functions in the ECDH |
| * module, restart is disabled unless the function accepts |
| * an "ECDH context" argument and |
| * mbedtls_ecdh_enable_restart() was previously called on |
| * that context. For function in the SSL module, restart is |
| * only enabled for specific sides and key exchanges |
| * (currently only for clients and ECDHE-ECDSA). |
| * |
| * \param max_ops Maximum number of basic operations done in a row. |
| * Default: 0 (unlimited). |
| * Lower (non-zero) values mean ECC functions will block for |
| * a lesser maximum amount of time. |
| * |
| * \note A "basic operation" is defined as a rough equivalent of a |
| * multiplication in GF(p) for the NIST P-256 curve. |
| * As an indication, with default settings, a scalar |
| * multiplication (full run of \c mbedtls_ecp_mul()) is: |
| * - about 3300 basic operations for P-256 |
| * - about 9400 basic operations for P-384 |
| * |
| * \note Very low values are not always respected: sometimes |
| * functions need to block for a minimum number of |
| * operations, and will do so even if max_ops is set to a |
| * lower value. That minimum depends on the curve size, and |
| * can be made lower by decreasing the value of |
| * \c MBEDTLS_ECP_WINDOW_SIZE. As an indication, here is the |
| * lowest effective value for various curves and values of |
| * that parameter (w for short): |
| * w=6 w=5 w=4 w=3 w=2 |
| * P-256 208 208 160 136 124 |
| * P-384 682 416 320 272 248 |
| * P-521 1364 832 640 544 496 |
| * |
| * \note This setting is currently ignored by Curve25519. |
| */ |
| void mbedtls_ecp_set_max_ops(unsigned max_ops); |
| |
| /** |
| * \brief Check if restart is enabled (max_ops != 0) |
| * |
| * \return \c 0 if \c max_ops == 0 (restart disabled) |
| * \return \c 1 otherwise (restart enabled) |
| */ |
| int mbedtls_ecp_restart_is_enabled(void); |
| #endif /* MBEDTLS_ECP_RESTARTABLE */ |
| |
| /* |
| * Get the type of a curve |
| */ |
| mbedtls_ecp_curve_type mbedtls_ecp_get_type(const mbedtls_ecp_group *grp); |
| |
| /** |
| * \brief This function retrieves the information defined in |
| * mbedtls_ecp_curve_info() for all supported curves. |
| * |
| * \note This function returns information about all curves |
| * supported by the library. Some curves may not be |
| * supported for all algorithms. Call mbedtls_ecdh_can_do() |
| * or mbedtls_ecdsa_can_do() to check if a curve is |
| * supported for ECDH or ECDSA. |
| * |
| * \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. |
| * |
| * \note This function returns information about all curves |
| * supported by the library. Some curves may not be |
| * supported for all algorithms. Call mbedtls_ecdh_can_do() |
| * or mbedtls_ecdsa_can_do() to check if a curve is |
| * supported for ECDH or ECDSA. |
| * |
| * \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_group_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. This may be \c NULL, in which |
| * case this function returns immediately. If it is not |
| * \c NULL, it must point to an initialized ECP group. |
| */ |
| 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. This may be \c NULL, in which |
| * case this function returns immediately. If it is not |
| * \c NULL, it must point to an initialized ECP key pair. |
| */ |
| void mbedtls_ecp_keypair_free(mbedtls_ecp_keypair *key); |
| |
| #if defined(MBEDTLS_ECP_RESTARTABLE) |
| /** |
| * \brief Initialize a restart context. |
| * |
| * \param ctx The restart context to initialize. This must |
| * not be \c NULL. |
| */ |
| void mbedtls_ecp_restart_init(mbedtls_ecp_restart_ctx *ctx); |
| |
| /** |
| * \brief Free the components of a restart context. |
| * |
| * \param ctx The restart context to free. This may be \c NULL, in which |
| * case this function returns immediately. If it is not |
| * \c NULL, it must point to an initialized restart context. |
| */ |
| void mbedtls_ecp_restart_free(mbedtls_ecp_restart_ctx *ctx); |
| #endif /* MBEDTLS_ECP_RESTARTABLE */ |
| |
| /** |
| * \brief This function copies the contents of point \p Q into |
| * point \p P. |
| * |
| * \param P The destination point. This must be initialized. |
| * \param Q The source point. This must be initialized. |
| * |
| * \return \c 0 on success. |
| * \return #MBEDTLS_ERR_MPI_ALLOC_FAILED on memory-allocation failure. |
| * \return Another negative error code for other kinds of 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. This must be initialized. |
| * \param src The source group. This must be initialized. |
| * |
| * \return \c 0 on success. |
| * \return #MBEDTLS_ERR_MPI_ALLOC_FAILED on memory-allocation failure. |
| * \return Another negative error code on other kinds of failure. |
| */ |
| int mbedtls_ecp_group_copy(mbedtls_ecp_group *dst, |
| const mbedtls_ecp_group *src); |
| |
| /** |
| * \brief This function sets a point to the point at infinity. |
| * |
| * \param pt The point to set. This must be initialized. |
| * |
| * \return \c 0 on success. |
| * \return #MBEDTLS_ERR_MPI_ALLOC_FAILED on memory-allocation failure. |
| * \return Another negative error code on other kinds of failure. |
| */ |
| int mbedtls_ecp_set_zero(mbedtls_ecp_point *pt); |
| |
| /** |
| * \brief This function checks if a point is the point at infinity. |
| * |
| * \param pt The point to test. This must be initialized. |
| * |
| * \return \c 1 if the point is zero. |
| * \return \c 0 if the point is non-zero. |
| * \return A negative error code on failure. |
| */ |
| 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. This must be initialized. |
| * \param Q The second point to compare. This must be initialized. |
| * |
| * \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. This must be initialized. |
| * \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. |
| * This must be initialized and have group parameters |
| * set, for example through mbedtls_ecp_group_load(). |
| * \param P The point to export. This must be initialized. |
| * \param format The point format. This must be either |
| * #MBEDTLS_ECP_PF_COMPRESSED or #MBEDTLS_ECP_PF_UNCOMPRESSED. |
| * (For groups without these formats, this parameter is |
| * ignored. But it still has to be either of the above |
| * values.) |
| * \param olen The address at which to store the length of |
| * the output in Bytes. This must not be \c NULL. |
| * \param buf The output buffer. This must be a writable buffer |
| * of length \p buflen Bytes. |
| * \param buflen The length of the output buffer \p buf in Bytes. |
| * |
| * \return \c 0 on success. |
| * \return #MBEDTLS_ERR_ECP_BUFFER_TOO_SMALL if the output buffer |
| * is too small to hold the point. |
| * \return #MBEDTLS_ERR_ECP_FEATURE_UNAVAILABLE if the point format |
| * or the export for the given group is not implemented. |
| * \return Another negative error code on other kinds of 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. |
| * This must be initialized and have group parameters |
| * set, for example through mbedtls_ecp_group_load(). |
| * \param P The destination context to import the point to. |
| * This must be initialized. |
| * \param buf The input buffer. This must be a readable buffer |
| * of length \p ilen Bytes. |
| * \param ilen The length of the input buffer \p buf in Bytes. |
| * |
| * \return \c 0 on success. |
| * \return #MBEDTLS_ERR_ECP_BAD_INPUT_DATA if the input is invalid. |
| * \return #MBEDTLS_ERR_MPI_ALLOC_FAILED on memory-allocation failure. |
| * \return #MBEDTLS_ERR_ECP_FEATURE_UNAVAILABLE if the import for the |
| * given group 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 immediately |
| * after the ECPoint record. |
| * |
| * \param grp The ECP group to use. |
| * This must be initialized and have group parameters |
| * set, for example through mbedtls_ecp_group_load(). |
| * \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 |
| * defined in RFC 4492, Section 5.4. |
| * |
| * \param grp The ECP group to use. |
| * This must be initialized and have group parameters |
| * set, for example through mbedtls_ecp_group_load(). |
| * \param pt The point to be exported. This must be initialized. |
| * \param format The point format to use. This must be either |
| * #MBEDTLS_ECP_PF_COMPRESSED or #MBEDTLS_ECP_PF_UNCOMPRESSED. |
| * \param olen The address at which to store the length in Bytes |
| * of the data written. |
| * \param buf The target buffer. This must be a writable buffer of |
| * length \p blen Bytes. |
| * \param blen The length of the target buffer \p buf in Bytes. |
| * |
| * \return \c 0 on success. |
| * \return #MBEDTLS_ERR_ECP_BAD_INPUT_DATA if the input is invalid. |
| * \return #MBEDTLS_ERR_ECP_BUFFER_TOO_SMALL if the target buffer |
| * is too small to hold the exported point. |
| * \return Another negative error code on other kinds of 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 up an ECP group context |
| * from a standardized set of 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 group context to setup. This must be initialized. |
| * \param id The identifier of the domain parameter set to load. |
| * |
| * \return \c 0 on success. |
| * \return #MBEDTLS_ERR_ECP_FEATURE_UNAVAILABLE if \p id doesn't |
| * correspond to a known group. |
| * \return Another negative error code on other kinds of failure. |
| */ |
| int mbedtls_ecp_group_load(mbedtls_ecp_group *grp, mbedtls_ecp_group_id id); |
| |
| /** |
| * \brief This function sets up an ECP group context from a TLS |
| * ECParameters record as defined in RFC 4492, Section 5.4. |
| * |
| * \note The read pointer \p buf is updated to point right after |
| * the ECParameters record on exit. |
| * |
| * \param grp The group context to setup. This must be initialized. |
| * \param buf The address of the pointer to the start of the input buffer. |
| * \param len The length of the input buffer \c *buf in Bytes. |
| * |
| * \return \c 0 on success. |
| * \return #MBEDTLS_ERR_ECP_BAD_INPUT_DATA if input is invalid. |
| * \return #MBEDTLS_ERR_ECP_FEATURE_UNAVAILABLE if the group is not |
| * recognized. |
| * \return Another negative error code on other kinds of failure. |
| */ |
| int mbedtls_ecp_tls_read_group(mbedtls_ecp_group *grp, |
| const unsigned char **buf, size_t len); |
| |
| /** |
| * \brief This function extracts an elliptic curve group ID from a |
| * TLS ECParameters record as defined in RFC 4492, Section 5.4. |
| * |
| * \note The read pointer \p buf is updated to point right after |
| * the ECParameters record on exit. |
| * |
| * \param grp The address at which to store the group id. |
| * This must not be \c NULL. |
| * \param buf The address of the pointer to the start of the input buffer. |
| * \param len The length of the input buffer \c *buf in Bytes. |
| * |
| * \return \c 0 on success. |
| * \return #MBEDTLS_ERR_ECP_BAD_INPUT_DATA if input is invalid. |
| * \return #MBEDTLS_ERR_ECP_FEATURE_UNAVAILABLE if the group is not |
| * recognized. |
| * \return Another negative error code on other kinds of failure. |
| */ |
| int mbedtls_ecp_tls_read_group_id(mbedtls_ecp_group_id *grp, |
| const unsigned char **buf, |
| size_t len); |
| /** |
| * \brief This function exports an elliptic curve as a TLS |
| * ECParameters record as defined in RFC 4492, Section 5.4. |
| * |
| * \param grp The ECP group to be exported. |
| * This must be initialized and have group parameters |
| * set, for example through mbedtls_ecp_group_load(). |
| * \param olen The address at which to store the number of Bytes written. |
| * This must not be \c NULL. |
| * \param buf The buffer to write to. This must be a writable buffer |
| * of length \p blen Bytes. |
| * \param blen The length of the output buffer \p buf in Bytes. |
| * |
| * \return \c 0 on success. |
| * \return #MBEDTLS_ERR_ECP_BUFFER_TOO_SMALL if the output |
| * buffer is too small to hold the exported group. |
| * \return Another negative error code on other kinds of 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 a scalar 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. |
| * Note: unless #MBEDTLS_ECP_NO_INTERNAL_RNG is defined, when |
| * \p f_rng is NULL, an internal RNG (seeded from the value |
| * of \p m) will be used instead. |
| * |
| * \param grp The ECP group to use. |
| * This must be initialized and have group parameters |
| * set, for example through mbedtls_ecp_group_load(). |
| * \param R The point in which to store the result of the calculation. |
| * This must be initialized. |
| * \param m The integer by which to multiply. This must be initialized. |
| * \param P The point to multiply. This must be initialized. |
| * \param f_rng The RNG function. This may be \c NULL if randomization |
| * of intermediate results isn't desired (discouraged). |
| * \param p_rng The RNG context to be passed to \p p_rng. |
| * |
| * \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. |
| * \return Another negative error code on other kinds of 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 of a point by |
| * an integer: \p R = \p m * \p P in a restartable way. |
| * |
| * \see mbedtls_ecp_mul() |
| * |
| * \note This function does the same as \c mbedtls_ecp_mul(), but |
| * it can return early and restart according to the limit set |
| * with \c mbedtls_ecp_set_max_ops() to reduce blocking. |
| * |
| * \param grp The ECP group to use. |
| * This must be initialized and have group parameters |
| * set, for example through mbedtls_ecp_group_load(). |
| * \param R The point in which to store the result of the calculation. |
| * This must be initialized. |
| * \param m The integer by which to multiply. This must be initialized. |
| * \param P The point to multiply. This must be initialized. |
| * \param f_rng The RNG function. This may be \c NULL if randomization |
| * of intermediate results isn't desired (discouraged). |
| * \param p_rng The RNG context to be passed to \p p_rng. |
| * \param rs_ctx The restart context (NULL disables restart). |
| * |
| * \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. |
| * \return #MBEDTLS_ERR_ECP_IN_PROGRESS if maximum number of |
| * operations was reached: see \c mbedtls_ecp_set_max_ops(). |
| * \return Another negative error code on other kinds of failure. |
| */ |
| 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); |
| |
| #if defined(MBEDTLS_ECP_SHORT_WEIERSTRASS_ENABLED) |
| /** |
| * \brief This function checks if domain parameter A of the curve is |
| * \c -3. |
| * |
| * \note This function is only defined for short Weierstrass curves. |
| * It may not be included in builds without any short |
| * Weierstrass curve. |
| * |
| * \param grp The ECP group to use. |
| * This must be initialized and have group parameters |
| * set, for example through mbedtls_ecp_group_load(). |
| * |
| * \return \c 1 if <code>A = -3</code>. |
| * \return \c 0 Otherwise. |
| */ |
| static inline int mbedtls_ecp_group_a_is_minus_3(const mbedtls_ecp_group *grp) |
| { |
| return grp->A.p == NULL; |
| } |
| |
| /** |
| * \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. |
| * |
| * \note This function is only defined for short Weierstrass curves. |
| * It may not be included in builds without any short |
| * Weierstrass curve. |
| * |
| * \param grp The ECP group to use. |
| * This must be initialized and have group parameters |
| * set, for example through mbedtls_ecp_group_load(). |
| * \param R The point in which to store the result of the calculation. |
| * This must be initialized. |
| * \param m The integer by which to multiply \p P. |
| * This must be initialized. |
| * \param P The point to multiply by \p m. This must be initialized. |
| * \param n The integer by which to multiply \p Q. |
| * This must be initialized. |
| * \param Q The point to be multiplied by \p n. |
| * This must be initialized. |
| * |
| * \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. |
| * \return #MBEDTLS_ERR_ECP_FEATURE_UNAVAILABLE if \p grp does not |
| * designate a short Weierstrass curve. |
| * \return Another negative error code on other kinds of 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 performs multiplication and addition of two |
| * points by integers: \p R = \p m * \p P + \p n * \p Q in a |
| * restartable way. |
| * |
| * \see \c mbedtls_ecp_muladd() |
| * |
| * \note This function works the same as \c mbedtls_ecp_muladd(), |
| * but it can return early and restart according to the limit |
| * set with \c mbedtls_ecp_set_max_ops() to reduce blocking. |
| * |
| * \note This function is only defined for short Weierstrass curves. |
| * It may not be included in builds without any short |
| * Weierstrass curve. |
| * |
| * \param grp The ECP group to use. |
| * This must be initialized and have group parameters |
| * set, for example through mbedtls_ecp_group_load(). |
| * \param R The point in which to store the result of the calculation. |
| * This must be initialized. |
| * \param m The integer by which to multiply \p P. |
| * This must be initialized. |
| * \param P The point to multiply by \p m. This must be initialized. |
| * \param n The integer by which to multiply \p Q. |
| * This must be initialized. |
| * \param Q The point to be multiplied by \p n. |
| * This must be initialized. |
| * \param rs_ctx The restart context (NULL disables restart). |
| * |
| * \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. |
| * \return #MBEDTLS_ERR_ECP_FEATURE_UNAVAILABLE if \p grp does not |
| * designate a short Weierstrass curve. |
| * \return #MBEDTLS_ERR_ECP_IN_PROGRESS if maximum number of |
| * operations was reached: see \c mbedtls_ecp_set_max_ops(). |
| * \return Another negative error code on other kinds of failure. |
| */ |
| 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); |
| #endif /* MBEDTLS_ECP_SHORT_WEIERSTRASS_ENABLED */ |
| |
| /** |
| * \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 \c 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 ECP group the point should belong to. |
| * This must be initialized and have group parameters |
| * set, for example through mbedtls_ecp_group_load(). |
| * \param pt The point to check. This must be initialized. |
| * |
| * \return \c 0 if the point is a valid public key. |
| * \return #MBEDTLS_ERR_ECP_INVALID_KEY if the point is not |
| * a valid public key for the given curve. |
| * \return Another negative error code on other kinds of failure. |
| */ |
| int mbedtls_ecp_check_pubkey(const mbedtls_ecp_group *grp, |
| const mbedtls_ecp_point *pt); |
| |
| /** |
| * \brief This function checks that an \c 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 ECP group the private key should belong to. |
| * This must be initialized and have group parameters |
| * set, for example through mbedtls_ecp_group_load(). |
| * \param d The integer to check. This must be initialized. |
| * |
| * \return \c 0 if the point is a valid private key. |
| * \return #MBEDTLS_ERR_ECP_INVALID_KEY if the point is not a valid |
| * private key for the given curve. |
| * \return Another negative error code on other kinds of failure. |
| */ |
| int mbedtls_ecp_check_privkey(const mbedtls_ecp_group *grp, |
| const mbedtls_mpi *d); |
| |
| /** |
| * \brief This function generates a private key. |
| * |
| * \param grp The ECP group to generate a private key for. |
| * This must be initialized and have group parameters |
| * set, for example through mbedtls_ecp_group_load(). |
| * \param d The destination MPI (secret part). This must be initialized. |
| * \param f_rng The RNG function. This must not be \c NULL. |
| * \param p_rng The RNG parameter to be passed to \p f_rng. This may be |
| * \c NULL if \p f_rng doesn't need a context argument. |
| * |
| * \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_privkey(const mbedtls_ecp_group *grp, |
| mbedtls_mpi *d, |
| int (*f_rng)(void *, unsigned char *, size_t), |
| void *p_rng); |
| |
| /** |
| * \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 to generate a key pair for. |
| * This must be initialized and have group parameters |
| * set, for example through mbedtls_ecp_group_load(). |
| * \param G The base point to use. This must be initialized |
| * and belong to \p grp. It replaces the default base |
| * point \c grp->G used by mbedtls_ecp_gen_keypair(). |
| * \param d The destination MPI (secret part). |
| * This must be initialized. |
| * \param Q The destination point (public part). |
| * This must be initialized. |
| * \param f_rng The RNG function. This must not be \c NULL. |
| * \param p_rng The RNG context to be passed to \p f_rng. This may |
| * be \c NULL if \p f_rng doesn't need a context argument. |
| * |
| * \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 to generate a key pair for. |
| * This must be initialized and have group parameters |
| * set, for example through mbedtls_ecp_group_load(). |
| * \param d The destination MPI (secret part). |
| * This must be initialized. |
| * \param Q The destination point (public part). |
| * This must be initialized. |
| * \param f_rng The RNG function. This must not be \c NULL. |
| * \param p_rng The RNG context to be passed to \p f_rng. This may |
| * be \c NULL if \p f_rng doesn't need a context argument. |
| * |
| * \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. This must be initialized. |
| * \param f_rng The RNG function to use. This must not be \c NULL. |
| * \param p_rng The RNG context to be passed to \p f_rng. This may |
| * be \c NULL if \p f_rng doesn't need a context argument. |
| * |
| * \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 reads an elliptic curve private key. |
| * |
| * \param grp_id The ECP group identifier. |
| * \param key The destination key. |
| * \param buf The buffer containing the binary representation of the |
| * key. (Big endian integer for Weierstrass curves, byte |
| * string for Montgomery curves.) |
| * \param buflen The length of the buffer in bytes. |
| * |
| * \return \c 0 on success. |
| * \return #MBEDTLS_ERR_ECP_INVALID_KEY error if the key is |
| * invalid. |
| * \return #MBEDTLS_ERR_MPI_ALLOC_FAILED if memory allocation failed. |
| * \return #MBEDTLS_ERR_ECP_FEATURE_UNAVAILABLE if the operation for |
| * the group is not implemented. |
| * \return Another negative error code on different kinds of failure. |
| */ |
| int mbedtls_ecp_read_key(mbedtls_ecp_group_id grp_id, mbedtls_ecp_keypair *key, |
| const unsigned char *buf, size_t buflen); |
| |
| /** |
| * \brief This function exports an elliptic curve private key. |
| * |
| * \param key The private key. |
| * \param buf The output buffer for containing the binary representation |
| * of the key. (Big endian integer for Weierstrass curves, byte |
| * string for Montgomery curves.) |
| * \param buflen The total length of the buffer in bytes. |
| * |
| * \return \c 0 on success. |
| * \return #MBEDTLS_ERR_ECP_BUFFER_TOO_SMALL if the \p key |
| representation is larger than the available space in \p buf. |
| * \return #MBEDTLS_ERR_ECP_FEATURE_UNAVAILABLE if the operation for |
| * the group is not implemented. |
| * \return Another negative error code on different kinds of failure. |
| */ |
| int mbedtls_ecp_write_key(mbedtls_ecp_keypair *key, |
| unsigned char *buf, size_t buflen); |
| |
| /** |
| * \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. This |
| * must be initialized. If it contains a private key, that |
| * part is ignored. |
| * \param prv The keypair structure holding the full keypair. |
| * This must be initialized. |
| * |
| * \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 */ |