1341 lines
58 KiB
C++
1341 lines
58 KiB
C++
/**
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* \file ecp.h
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*
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* \brief This file provides an API for Elliptic Curves over GF(P) (ECP).
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*
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* The use of ECP in cryptography and TLS is defined in
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* <em>Standards for Efficient Cryptography Group (SECG): SEC1
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* Elliptic Curve Cryptography</em> and
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* <em>RFC-4492: Elliptic Curve Cryptography (ECC) Cipher Suites
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* for Transport Layer Security (TLS)</em>.
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*
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* <em>RFC-2409: The Internet Key Exchange (IKE)</em> defines ECP
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* group types.
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*
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*/
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/*
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* Copyright The Mbed TLS Contributors
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* SPDX-License-Identifier: Apache-2.0 OR GPL-2.0-or-later
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*/
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#ifndef MBEDTLS_ECP_H
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#define MBEDTLS_ECP_H
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#if !defined(MBEDTLS_CONFIG_FILE)
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#include "mbedtls/config.h"
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#else
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#include MBEDTLS_CONFIG_FILE
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#endif
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#include "mbedtls/bignum.h"
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#if (defined(__ARMCC_VERSION) || defined(_MSC_VER)) && \
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!defined(inline) && !defined(__cplusplus)
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#define inline __inline
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#endif
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/*
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* ECP error codes
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*/
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/** Bad input parameters to function. */
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#define MBEDTLS_ERR_ECP_BAD_INPUT_DATA -0x4F80
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/** The buffer is too small to write to. */
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#define MBEDTLS_ERR_ECP_BUFFER_TOO_SMALL -0x4F00
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/** The requested feature is not available, for example, the requested curve is not supported. */
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#define MBEDTLS_ERR_ECP_FEATURE_UNAVAILABLE -0x4E80
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/** The signature is not valid. */
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#define MBEDTLS_ERR_ECP_VERIFY_FAILED -0x4E00
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/** Memory allocation failed. */
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#define MBEDTLS_ERR_ECP_ALLOC_FAILED -0x4D80
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/** Generation of random value, such as ephemeral key, failed. */
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#define MBEDTLS_ERR_ECP_RANDOM_FAILED -0x4D00
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/** Invalid private or public key. */
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#define MBEDTLS_ERR_ECP_INVALID_KEY -0x4C80
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/** The buffer contains a valid signature followed by more data. */
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#define MBEDTLS_ERR_ECP_SIG_LEN_MISMATCH -0x4C00
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/* MBEDTLS_ERR_ECP_HW_ACCEL_FAILED is deprecated and should not be used. */
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/** The ECP hardware accelerator failed. */
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#define MBEDTLS_ERR_ECP_HW_ACCEL_FAILED -0x4B80
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/** Operation in progress, call again with the same parameters to continue. */
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#define MBEDTLS_ERR_ECP_IN_PROGRESS -0x4B00
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/* Flags indicating whether to include code that is specific to certain
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* types of curves. These flags are for internal library use only. */
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#if defined(MBEDTLS_ECP_DP_SECP192R1_ENABLED) || \
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defined(MBEDTLS_ECP_DP_SECP224R1_ENABLED) || \
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defined(MBEDTLS_ECP_DP_SECP256R1_ENABLED) || \
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defined(MBEDTLS_ECP_DP_SECP384R1_ENABLED) || \
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defined(MBEDTLS_ECP_DP_SECP521R1_ENABLED) || \
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defined(MBEDTLS_ECP_DP_BP256R1_ENABLED) || \
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defined(MBEDTLS_ECP_DP_BP384R1_ENABLED) || \
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defined(MBEDTLS_ECP_DP_BP512R1_ENABLED) || \
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defined(MBEDTLS_ECP_DP_SECP192K1_ENABLED) || \
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defined(MBEDTLS_ECP_DP_SECP224K1_ENABLED) || \
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defined(MBEDTLS_ECP_DP_SECP256K1_ENABLED)
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#define MBEDTLS_ECP_SHORT_WEIERSTRASS_ENABLED
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#endif
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#if defined(MBEDTLS_ECP_DP_CURVE25519_ENABLED) || \
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defined(MBEDTLS_ECP_DP_CURVE448_ENABLED)
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#define MBEDTLS_ECP_MONTGOMERY_ENABLED
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#endif
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#ifdef __cplusplus
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extern "C" {
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#endif
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/**
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* Domain-parameter identifiers: curve, subgroup, and generator.
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*
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* \note Only curves over prime fields are supported.
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*
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* \warning This library does not support validation of arbitrary domain
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* parameters. Therefore, only standardized domain parameters from trusted
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* sources should be used. See mbedtls_ecp_group_load().
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*/
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/* Note: when adding a new curve:
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* - Add it at the end of this enum, otherwise you'll break the ABI by
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* changing the numerical value for existing curves.
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* - Increment MBEDTLS_ECP_DP_MAX below if needed.
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* - Update the calculation of MBEDTLS_ECP_MAX_BITS_MIN below.
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* - Add the corresponding MBEDTLS_ECP_DP_xxx_ENABLED macro definition to
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* config.h.
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* - List the curve as a dependency of MBEDTLS_ECP_C and
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* MBEDTLS_ECDSA_C if supported in check_config.h.
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* - Add the curve to the appropriate curve type macro
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* MBEDTLS_ECP_yyy_ENABLED above.
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* - Add the necessary definitions to ecp_curves.c.
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* - Add the curve to the ecp_supported_curves array in ecp.c.
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* - Add the curve to applicable profiles in x509_crt.c if applicable.
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*/
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typedef enum {
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MBEDTLS_ECP_DP_NONE = 0, /*!< Curve not defined. */
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MBEDTLS_ECP_DP_SECP192R1, /*!< Domain parameters for the 192-bit curve defined by FIPS 186-4 and SEC1. */
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MBEDTLS_ECP_DP_SECP224R1, /*!< Domain parameters for the 224-bit curve defined by FIPS 186-4 and SEC1. */
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MBEDTLS_ECP_DP_SECP256R1, /*!< Domain parameters for the 256-bit curve defined by FIPS 186-4 and SEC1. */
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MBEDTLS_ECP_DP_SECP384R1, /*!< Domain parameters for the 384-bit curve defined by FIPS 186-4 and SEC1. */
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MBEDTLS_ECP_DP_SECP521R1, /*!< Domain parameters for the 521-bit curve defined by FIPS 186-4 and SEC1. */
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MBEDTLS_ECP_DP_BP256R1, /*!< Domain parameters for 256-bit Brainpool curve. */
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MBEDTLS_ECP_DP_BP384R1, /*!< Domain parameters for 384-bit Brainpool curve. */
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MBEDTLS_ECP_DP_BP512R1, /*!< Domain parameters for 512-bit Brainpool curve. */
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MBEDTLS_ECP_DP_CURVE25519, /*!< Domain parameters for Curve25519. */
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MBEDTLS_ECP_DP_SECP192K1, /*!< Domain parameters for 192-bit "Koblitz" curve. */
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MBEDTLS_ECP_DP_SECP224K1, /*!< Domain parameters for 224-bit "Koblitz" curve. */
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MBEDTLS_ECP_DP_SECP256K1, /*!< Domain parameters for 256-bit "Koblitz" curve. */
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MBEDTLS_ECP_DP_CURVE448, /*!< Domain parameters for Curve448. */
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} mbedtls_ecp_group_id;
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/**
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* The number of supported curves, plus one for #MBEDTLS_ECP_DP_NONE.
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*
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* \note Montgomery curves are currently excluded.
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*/
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#define MBEDTLS_ECP_DP_MAX 12
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/*
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* Curve types
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*/
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typedef enum {
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MBEDTLS_ECP_TYPE_NONE = 0,
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MBEDTLS_ECP_TYPE_SHORT_WEIERSTRASS, /* y^2 = x^3 + a x + b */
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MBEDTLS_ECP_TYPE_MONTGOMERY, /* y^2 = x^3 + a x^2 + x */
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} mbedtls_ecp_curve_type;
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/**
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* Curve information, for use by other modules.
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*/
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typedef struct mbedtls_ecp_curve_info {
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mbedtls_ecp_group_id grp_id; /*!< An internal identifier. */
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uint16_t tls_id; /*!< The TLS NamedCurve identifier. */
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uint16_t bit_size; /*!< The curve size in bits. */
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const char *name; /*!< A human-friendly name. */
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} mbedtls_ecp_curve_info;
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/**
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* \brief The ECP point structure, in Jacobian coordinates.
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*
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* \note All functions expect and return points satisfying
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* the following condition: <code>Z == 0</code> or
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* <code>Z == 1</code>. Other values of \p Z are
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* used only by internal functions.
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* The point is zero, or "at infinity", if <code>Z == 0</code>.
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* Otherwise, \p X and \p Y are its standard (affine)
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* coordinates.
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*/
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typedef struct mbedtls_ecp_point {
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mbedtls_mpi X; /*!< The X coordinate of the ECP point. */
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mbedtls_mpi Y; /*!< The Y coordinate of the ECP point. */
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mbedtls_mpi Z; /*!< The Z coordinate of the ECP point. */
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}
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mbedtls_ecp_point;
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/* Determine the minimum safe value of MBEDTLS_ECP_MAX_BITS. */
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#if !defined(MBEDTLS_ECP_C)
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#define MBEDTLS_ECP_MAX_BITS_MIN 0
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/* Note: the curves must be listed in DECREASING size! */
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#elif defined(MBEDTLS_ECP_DP_SECP521R1_ENABLED)
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#define MBEDTLS_ECP_MAX_BITS_MIN 521
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#elif defined(MBEDTLS_ECP_DP_BP512R1_ENABLED)
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#define MBEDTLS_ECP_MAX_BITS_MIN 512
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#elif defined(MBEDTLS_ECP_DP_CURVE448_ENABLED)
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#define MBEDTLS_ECP_MAX_BITS_MIN 448
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#elif defined(MBEDTLS_ECP_DP_BP384R1_ENABLED)
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#define MBEDTLS_ECP_MAX_BITS_MIN 384
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#elif defined(MBEDTLS_ECP_DP_SECP384R1_ENABLED)
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#define MBEDTLS_ECP_MAX_BITS_MIN 384
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#elif defined(MBEDTLS_ECP_DP_BP256R1_ENABLED)
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#define MBEDTLS_ECP_MAX_BITS_MIN 256
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#elif defined(MBEDTLS_ECP_DP_SECP256K1_ENABLED)
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#define MBEDTLS_ECP_MAX_BITS_MIN 256
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#elif defined(MBEDTLS_ECP_DP_SECP256R1_ENABLED)
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#define MBEDTLS_ECP_MAX_BITS_MIN 256
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#elif defined(MBEDTLS_ECP_DP_CURVE25519_ENABLED)
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#define MBEDTLS_ECP_MAX_BITS_MIN 255
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#elif defined(MBEDTLS_ECP_DP_SECP224K1_ENABLED)
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#define MBEDTLS_ECP_MAX_BITS_MIN 225 // n is slightly above 2^224
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#elif defined(MBEDTLS_ECP_DP_SECP224R1_ENABLED)
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#define MBEDTLS_ECP_MAX_BITS_MIN 224
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#elif defined(MBEDTLS_ECP_DP_SECP192K1_ENABLED)
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#define MBEDTLS_ECP_MAX_BITS_MIN 192
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#elif defined(MBEDTLS_ECP_DP_SECP192R1_ENABLED)
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#define MBEDTLS_ECP_MAX_BITS_MIN 192
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#else
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#error "MBEDTLS_ECP_C enabled, but no curve?"
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#endif
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#if !defined(MBEDTLS_ECP_ALT)
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/*
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* default Mbed TLS elliptic curve arithmetic implementation
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*
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* (in case MBEDTLS_ECP_ALT is defined then the developer has to provide an
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* alternative implementation for the whole module and it will replace this
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* one.)
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*/
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/**
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* \brief The ECP group structure.
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*
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* We consider two types of curve equations:
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* <ul><li>Short Weierstrass: <code>y^2 = x^3 + A x + B mod P</code>
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* (SEC1 + RFC-4492)</li>
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* <li>Montgomery: <code>y^2 = x^3 + A x^2 + x mod P</code> (Curve25519,
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* Curve448)</li></ul>
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* In both cases, the generator (\p G) for a prime-order subgroup is fixed.
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*
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* For Short Weierstrass, this subgroup is the whole curve, and its
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* cardinality is denoted by \p N. Our code requires that \p N is an
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* odd prime as mbedtls_ecp_mul() requires an odd number, and
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* mbedtls_ecdsa_sign() requires that it is prime for blinding purposes.
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*
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* The default implementation only initializes \p A without setting it to the
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* authentic value for curves with <code>A = -3</code>(SECP256R1, etc), in which
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* case you need to load \p A by yourself when using domain parameters directly,
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* for example:
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* \code
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* mbedtls_mpi_init(&A);
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* mbedtls_ecp_group_init(&grp);
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* CHECK_RETURN(mbedtls_ecp_group_load(&grp, grp_id));
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* if (mbedtls_ecp_group_a_is_minus_3(&grp)) {
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* CHECK_RETURN(mbedtls_mpi_sub_int(&A, &grp.P, 3));
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* } else {
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* CHECK_RETURN(mbedtls_mpi_copy(&A, &grp.A));
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* }
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*
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* do_something_with_a(&A);
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*
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* cleanup:
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* mbedtls_mpi_free(&A);
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* mbedtls_ecp_group_free(&grp);
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* \endcode
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*
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* For Montgomery curves, we do not store \p A, but <code>(A + 2) / 4</code>,
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* which is the quantity used in the formulas. Additionally, \p nbits is
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* not the size of \p N but the required size for private keys.
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*
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* If \p modp is NULL, reduction modulo \p P is done using a generic algorithm.
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* Otherwise, \p modp must point to a function that takes an \p mbedtls_mpi in the
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* range of <code>0..2^(2*pbits)-1</code>, and transforms it in-place to an integer
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* which is congruent mod \p P to the given MPI, and is close enough to \p pbits
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* in size, so that it may be efficiently brought in the 0..P-1 range by a few
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* additions or subtractions. Therefore, it is only an approximative modular
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* reduction. It must return 0 on success and non-zero on failure.
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*
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* \note Alternative implementations must keep the group IDs distinct. If
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* two group structures have the same ID, then they must be
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* identical.
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*
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*/
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typedef struct mbedtls_ecp_group {
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mbedtls_ecp_group_id id; /*!< An internal group identifier. */
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mbedtls_mpi P; /*!< The prime modulus of the base field. */
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mbedtls_mpi A; /*!< For Short Weierstrass: \p A in the equation. Note that
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\p A is not set to the authentic value in some cases.
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Refer to detailed description of ::mbedtls_ecp_group if
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using domain parameters in the structure.
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For Montgomery curves: <code>(A + 2) / 4</code>. */
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mbedtls_mpi B; /*!< For Short Weierstrass: \p B in the equation.
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For Montgomery curves: unused. */
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mbedtls_ecp_point G; /*!< The generator of the subgroup used. */
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mbedtls_mpi N; /*!< The order of \p G. */
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size_t pbits; /*!< The number of bits in \p P.*/
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size_t nbits; /*!< For Short Weierstrass: The number of bits in \p P.
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For Montgomery curves: the number of bits in the
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private keys. */
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unsigned int h; /*!< \internal 1 if the constants are static. */
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int (*modp)(mbedtls_mpi *); /*!< The function for fast pseudo-reduction
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mod \p P (see above).*/
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int (*t_pre)(mbedtls_ecp_point *, void *); /*!< Unused. */
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int (*t_post)(mbedtls_ecp_point *, void *); /*!< Unused. */
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void *t_data; /*!< Unused. */
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mbedtls_ecp_point *T; /*!< Pre-computed points for ecp_mul_comb(). */
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size_t T_size; /*!< The number of pre-computed points. */
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}
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mbedtls_ecp_group;
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/**
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* \name SECTION: Module settings
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*
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* The configuration options you can set for this module are in this section.
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* Either change them in config.h, or define them using the compiler command line.
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* \{
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*/
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#if defined(MBEDTLS_ECP_MAX_BITS)
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#if MBEDTLS_ECP_MAX_BITS < MBEDTLS_ECP_MAX_BITS_MIN
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#error "MBEDTLS_ECP_MAX_BITS is smaller than the largest supported curve"
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#endif
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#elif defined(MBEDTLS_ECP_C)
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/**
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* The maximum size of the groups, that is, of \c N and \c P.
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*/
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#define MBEDTLS_ECP_MAX_BITS MBEDTLS_ECP_MAX_BITS_MIN
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#else
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/* MBEDTLS_ECP_MAX_BITS is not relevant without MBEDTLS_ECP_C, but set it
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* to a nonzero value so that code that unconditionally allocates an array
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* of a size based on it keeps working if built without ECC support. */
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#define MBEDTLS_ECP_MAX_BITS 1
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#endif
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#define MBEDTLS_ECP_MAX_BYTES ((MBEDTLS_ECP_MAX_BITS + 7) / 8)
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#define MBEDTLS_ECP_MAX_PT_LEN (2 * MBEDTLS_ECP_MAX_BYTES + 1)
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#if !defined(MBEDTLS_ECP_WINDOW_SIZE)
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/*
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* Maximum "window" size used for point multiplication.
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* Default: a point where higher memory usage yields diminishing performance
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* returns.
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* Minimum value: 2. Maximum value: 7.
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*
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* Result is an array of at most ( 1 << ( MBEDTLS_ECP_WINDOW_SIZE - 1 ) )
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* points used for point multiplication. This value is directly tied to EC
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* peak memory usage, so decreasing it by one should roughly cut memory usage
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* by two (if large curves are in use).
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*
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* Reduction in size may reduce speed, but larger curves are impacted first.
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* Sample performances (in ECDHE handshakes/s, with FIXED_POINT_OPTIM = 1):
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* w-size: 6 5 4 3 2
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* 521 145 141 135 120 97
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* 384 214 209 198 177 146
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* 256 320 320 303 262 226
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* 224 475 475 453 398 342
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* 192 640 640 633 587 476
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*/
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#define MBEDTLS_ECP_WINDOW_SIZE 4 /**< The maximum window size used. */
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#endif /* MBEDTLS_ECP_WINDOW_SIZE */
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#if !defined(MBEDTLS_ECP_FIXED_POINT_OPTIM)
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/*
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* Trade memory for speed on fixed-point multiplication.
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*
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* This speeds up repeated multiplication of the generator (that is, the
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* multiplication in ECDSA signatures, and half of the multiplications in
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* ECDSA verification and ECDHE) by a factor roughly 3 to 4.
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*
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* The cost is increasing EC peak memory usage by a factor roughly 2.
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*
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* Change this value to 0 to reduce peak memory usage.
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*/
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#define MBEDTLS_ECP_FIXED_POINT_OPTIM 1 /**< Enable fixed-point speed-up. */
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#endif /* MBEDTLS_ECP_FIXED_POINT_OPTIM */
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/** \} name SECTION: Module settings */
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#else /* MBEDTLS_ECP_ALT */
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#include "ecp_alt.h"
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#endif /* MBEDTLS_ECP_ALT */
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#if defined(MBEDTLS_ECP_RESTARTABLE)
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/**
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* \brief Internal restart context for multiplication
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*
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* \note Opaque struct
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*/
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typedef struct mbedtls_ecp_restart_mul mbedtls_ecp_restart_mul_ctx;
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/**
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* \brief Internal restart context for ecp_muladd()
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*
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* \note Opaque struct
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*/
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typedef struct mbedtls_ecp_restart_muladd mbedtls_ecp_restart_muladd_ctx;
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/**
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* \brief General context for resuming ECC operations
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*/
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typedef struct {
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unsigned ops_done; /*!< current ops count */
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unsigned depth; /*!< call depth (0 = top-level) */
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mbedtls_ecp_restart_mul_ctx *rsm; /*!< ecp_mul_comb() sub-context */
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mbedtls_ecp_restart_muladd_ctx *ma; /*!< ecp_muladd() sub-context */
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} mbedtls_ecp_restart_ctx;
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/*
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* Operation counts for restartable functions
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*/
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#define MBEDTLS_ECP_OPS_CHK 3 /*!< basic ops count for ecp_check_pubkey() */
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#define MBEDTLS_ECP_OPS_DBL 8 /*!< basic ops count for ecp_double_jac() */
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#define MBEDTLS_ECP_OPS_ADD 11 /*!< basic ops count for see ecp_add_mixed() */
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#define MBEDTLS_ECP_OPS_INV 120 /*!< empirical equivalent for mpi_mod_inv() */
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|
|
|
/**
|
|
* \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 */
|