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Diffstat (limited to 'include/mbedtls/ecdh.h')
| -rw-r--r-- | include/mbedtls/ecdh.h | 441 |
1 files changed, 0 insertions, 441 deletions
diff --git a/include/mbedtls/ecdh.h b/include/mbedtls/ecdh.h deleted file mode 100644 index 792db79..0000000 --- a/include/mbedtls/ecdh.h +++ /dev/null @@ -1,441 +0,0 @@ -/** - * \file ecdh.h - * - * \brief This file contains ECDH definitions and functions. - * - * The Elliptic Curve Diffie-Hellman (ECDH) protocol is an anonymous - * key agreement protocol allowing two parties to establish a shared - * secret over an insecure channel. Each party must have an - * elliptic-curve public–private key pair. - * - * For more information, see <em>NIST SP 800-56A Rev. 2: Recommendation for - * Pair-Wise Key Establishment Schemes Using Discrete Logarithm - * Cryptography</em>. - */ -/* - * Copyright The Mbed TLS Contributors - * SPDX-License-Identifier: Apache-2.0 OR GPL-2.0-or-later - */ - -#ifndef MBEDTLS_ECDH_H -#define MBEDTLS_ECDH_H -#include "mbedtls/private_access.h" - -#include "mbedtls/build_info.h" - -#include "mbedtls/ecp.h" - -/* - * Mbed TLS supports two formats for ECDH contexts (#mbedtls_ecdh_context - * defined in `ecdh.h`). For most applications, the choice of format makes - * no difference, since all library functions can work with either format, - * except that the new format is incompatible with MBEDTLS_ECP_RESTARTABLE. - - * The new format used when this option is disabled is smaller - * (56 bytes on a 32-bit platform). In future versions of the library, it - * will support alternative implementations of ECDH operations. - * The new format is incompatible with applications that access - * context fields directly and with restartable ECP operations. - */ - -#if defined(MBEDTLS_ECP_RESTARTABLE) -#define MBEDTLS_ECDH_LEGACY_CONTEXT -#else -#undef MBEDTLS_ECDH_LEGACY_CONTEXT -#endif - -#if defined(MBEDTLS_ECDH_VARIANT_EVEREST_ENABLED) -#undef MBEDTLS_ECDH_LEGACY_CONTEXT -#include "everest/everest.h" -#endif - -#ifdef __cplusplus -extern "C" { -#endif - -/** - * Defines the source of the imported EC key. - */ -typedef enum { - MBEDTLS_ECDH_OURS, /**< Our key. */ - MBEDTLS_ECDH_THEIRS, /**< The key of the peer. */ -} mbedtls_ecdh_side; - -#if !defined(MBEDTLS_ECDH_LEGACY_CONTEXT) -/** - * Defines the ECDH implementation used. - * - * Later versions of the library may add new variants, therefore users should - * not make any assumptions about them. - */ -typedef enum { - MBEDTLS_ECDH_VARIANT_NONE = 0, /*!< Implementation not defined. */ - MBEDTLS_ECDH_VARIANT_MBEDTLS_2_0,/*!< The default Mbed TLS implementation */ -#if defined(MBEDTLS_ECDH_VARIANT_EVEREST_ENABLED) - MBEDTLS_ECDH_VARIANT_EVEREST /*!< Everest implementation */ -#endif -} mbedtls_ecdh_variant; - -/** - * The context used by the default ECDH implementation. - * - * Later versions might change the structure of this context, therefore users - * should not make any assumptions about the structure of - * mbedtls_ecdh_context_mbed. - */ -typedef struct mbedtls_ecdh_context_mbed { - mbedtls_ecp_group MBEDTLS_PRIVATE(grp); /*!< The elliptic curve used. */ - mbedtls_mpi MBEDTLS_PRIVATE(d); /*!< The private key. */ - mbedtls_ecp_point MBEDTLS_PRIVATE(Q); /*!< The public key. */ - mbedtls_ecp_point MBEDTLS_PRIVATE(Qp); /*!< The value of the public key of the peer. */ - mbedtls_mpi MBEDTLS_PRIVATE(z); /*!< The shared secret. */ -#if defined(MBEDTLS_ECP_RESTARTABLE) - mbedtls_ecp_restart_ctx MBEDTLS_PRIVATE(rs); /*!< The restart context for EC computations. */ -#endif -} mbedtls_ecdh_context_mbed; -#endif - -/** - * - * \warning Performing multiple operations concurrently on the same - * ECDSA context is not supported; objects of this type - * should not be shared between multiple threads. - * \brief The ECDH context structure. - */ -typedef struct mbedtls_ecdh_context { -#if defined(MBEDTLS_ECDH_LEGACY_CONTEXT) - mbedtls_ecp_group MBEDTLS_PRIVATE(grp); /*!< The elliptic curve used. */ - mbedtls_mpi MBEDTLS_PRIVATE(d); /*!< The private key. */ - mbedtls_ecp_point MBEDTLS_PRIVATE(Q); /*!< The public key. */ - mbedtls_ecp_point MBEDTLS_PRIVATE(Qp); /*!< The value of the public key of the peer. */ - mbedtls_mpi MBEDTLS_PRIVATE(z); /*!< The shared secret. */ - int MBEDTLS_PRIVATE(point_format); /*!< The format of point export in TLS messages. */ - mbedtls_ecp_point MBEDTLS_PRIVATE(Vi); /*!< The blinding value. */ - mbedtls_ecp_point MBEDTLS_PRIVATE(Vf); /*!< The unblinding value. */ - mbedtls_mpi MBEDTLS_PRIVATE(_d); /*!< The previous \p d. */ -#if defined(MBEDTLS_ECP_RESTARTABLE) - int MBEDTLS_PRIVATE(restart_enabled); /*!< The flag for restartable mode. */ - mbedtls_ecp_restart_ctx MBEDTLS_PRIVATE(rs); /*!< The restart context for EC computations. */ -#endif /* MBEDTLS_ECP_RESTARTABLE */ -#else - uint8_t MBEDTLS_PRIVATE(point_format); /*!< The format of point export in TLS messages - as defined in RFC 4492. */ - mbedtls_ecp_group_id MBEDTLS_PRIVATE(grp_id);/*!< The elliptic curve used. */ - mbedtls_ecdh_variant MBEDTLS_PRIVATE(var); /*!< The ECDH implementation/structure used. */ - union { - mbedtls_ecdh_context_mbed MBEDTLS_PRIVATE(mbed_ecdh); -#if defined(MBEDTLS_ECDH_VARIANT_EVEREST_ENABLED) - mbedtls_ecdh_context_everest MBEDTLS_PRIVATE(everest_ecdh); -#endif - } MBEDTLS_PRIVATE(ctx); /*!< Implementation-specific context. The - context in use is specified by the \c var - field. */ -#if defined(MBEDTLS_ECP_RESTARTABLE) - uint8_t MBEDTLS_PRIVATE(restart_enabled); /*!< The flag for restartable mode. Functions of - an alternative implementation not supporting - restartable mode must return - MBEDTLS_ERR_PLATFORM_FEATURE_UNSUPPORTED error - if this flag is set. */ -#endif /* MBEDTLS_ECP_RESTARTABLE */ -#endif /* MBEDTLS_ECDH_LEGACY_CONTEXT */ -} -mbedtls_ecdh_context; - -/** - * \brief Check whether a given group can be used for ECDH. - * - * \param gid The ECP group ID to check. - * - * \return \c 1 if the group can be used, \c 0 otherwise - */ -int mbedtls_ecdh_can_do(mbedtls_ecp_group_id gid); - -/** - * \brief This function generates an ECDH keypair on an elliptic - * curve. - * - * This function performs the first of two core computations - * implemented during the ECDH key exchange. The second core - * computation is performed by mbedtls_ecdh_compute_shared(). - * - * \see ecp.h - * - * \param grp The ECP group to use. This must be initialized and have - * domain parameters loaded, for example through - * mbedtls_ecp_load() or mbedtls_ecp_tls_read_group(). - * \param d The destination MPI (private key). - * This must be initialized. - * \param Q The destination point (public 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 in case \p f_rng doesn't need a context argument. - * - * \return \c 0 on success. - * \return Another \c MBEDTLS_ERR_ECP_XXX or - * \c MBEDTLS_MPI_XXX error code on failure. - */ -int mbedtls_ecdh_gen_public(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 computes the shared secret. - * - * This function performs the second of two core computations - * implemented during the ECDH key exchange. The first core - * computation is performed by mbedtls_ecdh_gen_public(). - * - * \see ecp.h - * - * \note If \p f_rng is not NULL, it is used to implement - * countermeasures against side-channel attacks. - * For more information, see mbedtls_ecp_mul(). - * - * \param grp The ECP group to use. This must be initialized and have - * domain parameters loaded, for example through - * mbedtls_ecp_load() or mbedtls_ecp_tls_read_group(). - * \param z The destination MPI (shared secret). - * This must be initialized. - * \param Q The public key from another party. - * This must be initialized. - * \param d Our secret exponent (private 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 is \c NULL or doesn't need a - * context argument. - * - * \return \c 0 on success. - * \return Another \c MBEDTLS_ERR_ECP_XXX or - * \c MBEDTLS_MPI_XXX error code on failure. - */ -int mbedtls_ecdh_compute_shared(mbedtls_ecp_group *grp, mbedtls_mpi *z, - const mbedtls_ecp_point *Q, const mbedtls_mpi *d, - int (*f_rng)(void *, unsigned char *, size_t), - void *p_rng); - -/** - * \brief This function initializes an ECDH context. - * - * \param ctx The ECDH context to initialize. This must not be \c NULL. - */ -void mbedtls_ecdh_init(mbedtls_ecdh_context *ctx); - -/** - * \brief This function sets up the ECDH context with the information - * given. - * - * This function should be called after mbedtls_ecdh_init() but - * before mbedtls_ecdh_make_params(). There is no need to call - * this function before mbedtls_ecdh_read_params(). - * - * This is the first function used by a TLS server for ECDHE - * ciphersuites. - * - * \param ctx The ECDH context to set up. This must be initialized. - * \param grp_id The group id of the group to set up the context for. - * - * \return \c 0 on success. - */ -int mbedtls_ecdh_setup(mbedtls_ecdh_context *ctx, - mbedtls_ecp_group_id grp_id); - -/** - * \brief This function frees a context. - * - * \param ctx The context to free. This may be \c NULL, in which - * case this function does nothing. If it is not \c NULL, - * it must point to an initialized ECDH context. - */ -void mbedtls_ecdh_free(mbedtls_ecdh_context *ctx); - -/** - * \brief This function generates an EC key pair and exports its - * in the format used in a TLS ServerKeyExchange handshake - * message. - * - * This is the second function used by a TLS server for ECDHE - * ciphersuites. (It is called after mbedtls_ecdh_setup().) - * - * \see ecp.h - * - * \param ctx The ECDH context to use. This must be initialized - * and bound to a group, for example via mbedtls_ecdh_setup(). - * \param olen The address at which to store the number of Bytes written. - * \param buf The destination buffer. This must be a writable buffer of - * length \p blen Bytes. - * \param blen The length of the destination buffer \p buf in Bytes. - * \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 in case \p f_rng doesn't need a context argument. - * - * \return \c 0 on success. - * \return #MBEDTLS_ERR_ECP_IN_PROGRESS if maximum number of - * operations was reached: see \c mbedtls_ecp_set_max_ops(). - * \return Another \c MBEDTLS_ERR_ECP_XXX error code on failure. - */ -int mbedtls_ecdh_make_params(mbedtls_ecdh_context *ctx, size_t *olen, - unsigned char *buf, size_t blen, - int (*f_rng)(void *, unsigned char *, size_t), - void *p_rng); - -/** - * \brief This function parses the ECDHE parameters in a - * TLS ServerKeyExchange handshake message. - * - * \note In a TLS handshake, this is the how the client - * sets up its ECDHE context from the server's public - * ECDHE key material. - * - * \see ecp.h - * - * \param ctx The ECDHE context to use. This must be initialized. - * \param buf On input, \c *buf must be the start of the input buffer. - * On output, \c *buf is updated to point to the end of the - * data that has been read. On success, this is the first byte - * past the end of the ServerKeyExchange parameters. - * On error, this is the point at which an error has been - * detected, which is usually not useful except to debug - * failures. - * \param end The end of the input buffer. - * - * \return \c 0 on success. - * \return An \c MBEDTLS_ERR_ECP_XXX error code on failure. - * - */ -int mbedtls_ecdh_read_params(mbedtls_ecdh_context *ctx, - const unsigned char **buf, - const unsigned char *end); - -/** - * \brief This function sets up an ECDH context from an EC key. - * - * It is used by clients and servers in place of the - * ServerKeyEchange for static ECDH, and imports ECDH - * parameters from the EC key information of a certificate. - * - * \see ecp.h - * - * \param ctx The ECDH context to set up. This must be initialized. - * \param key The EC key to use. This must be initialized. - * \param side Defines the source of the key. Possible values are: - * - #MBEDTLS_ECDH_OURS: The key is ours. - * - #MBEDTLS_ECDH_THEIRS: The key is that of the peer. - * - * \return \c 0 on success. - * \return Another \c MBEDTLS_ERR_ECP_XXX error code on failure. - * - */ -int mbedtls_ecdh_get_params(mbedtls_ecdh_context *ctx, - const mbedtls_ecp_keypair *key, - mbedtls_ecdh_side side); - -/** - * \brief This function generates a public key and exports it - * as a TLS ClientKeyExchange payload. - * - * This is the second function used by a TLS client for ECDH(E) - * ciphersuites. - * - * \see ecp.h - * - * \param ctx The ECDH context to use. This must be initialized - * and bound to a group, the latter usually by - * mbedtls_ecdh_read_params(). - * \param olen The address at which to store the number of Bytes written. - * This must not be \c NULL. - * \param buf The destination buffer. This must be a writable buffer - * of length \p blen Bytes. - * \param blen The size of the destination buffer \p buf in Bytes. - * \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 in case \p f_rng doesn't need a context argument. - * - * \return \c 0 on success. - * \return #MBEDTLS_ERR_ECP_IN_PROGRESS if maximum number of - * operations was reached: see \c mbedtls_ecp_set_max_ops(). - * \return Another \c MBEDTLS_ERR_ECP_XXX error code on failure. - */ -int mbedtls_ecdh_make_public(mbedtls_ecdh_context *ctx, size_t *olen, - unsigned char *buf, size_t blen, - int (*f_rng)(void *, unsigned char *, size_t), - void *p_rng); - -/** - * \brief This function parses and processes the ECDHE payload of a - * TLS ClientKeyExchange message. - * - * This is the third function used by a TLS server for ECDH(E) - * ciphersuites. (It is called after mbedtls_ecdh_setup() and - * mbedtls_ecdh_make_params().) - * - * \see ecp.h - * - * \param ctx The ECDH context to use. This must be initialized - * and bound to a group, for example via mbedtls_ecdh_setup(). - * \param buf The pointer to the ClientKeyExchange payload. This must - * be a readable buffer of length \p blen Bytes. - * \param blen The length of the input buffer \p buf in Bytes. - * - * \return \c 0 on success. - * \return An \c MBEDTLS_ERR_ECP_XXX error code on failure. - */ -int mbedtls_ecdh_read_public(mbedtls_ecdh_context *ctx, - const unsigned char *buf, size_t blen); - -/** - * \brief This function derives and exports the shared secret. - * - * This is the last function used by both TLS client - * and servers. - * - * \note If \p f_rng is not NULL, it is used to implement - * countermeasures against side-channel attacks. - * For more information, see mbedtls_ecp_mul(). - * - * \see ecp.h - - * \param ctx The ECDH context to use. This must be initialized - * and have its own private key generated and the peer's - * public key imported. - * \param olen The address at which to store the total number of - * Bytes written on success. This must not be \c NULL. - * \param buf The buffer to write the generated shared key to. This - * must be a writable buffer of size \p blen Bytes. - * \param blen The length of the destination buffer \p buf in Bytes. - * \param f_rng The RNG function to use. This must not be \c NULL. - * \param p_rng The RNG context. This may be \c NULL if \p f_rng - * doesn't need a context argument. - * - * \return \c 0 on success. - * \return #MBEDTLS_ERR_ECP_IN_PROGRESS if maximum number of - * operations was reached: see \c mbedtls_ecp_set_max_ops(). - * \return Another \c MBEDTLS_ERR_ECP_XXX error code on failure. - */ -int mbedtls_ecdh_calc_secret(mbedtls_ecdh_context *ctx, size_t *olen, - unsigned char *buf, size_t blen, - int (*f_rng)(void *, unsigned char *, size_t), - void *p_rng); - -#if defined(MBEDTLS_ECP_RESTARTABLE) -/** - * \brief This function enables restartable EC computations for this - * context. (Default: disabled.) - * - * \see \c mbedtls_ecp_set_max_ops() - * - * \note It is not possible to safely disable restartable - * computations once enabled, except by free-ing the context, - * which cancels possible in-progress operations. - * - * \param ctx The ECDH context to use. This must be initialized. - */ -void mbedtls_ecdh_enable_restart(mbedtls_ecdh_context *ctx); -#endif /* MBEDTLS_ECP_RESTARTABLE */ - -#ifdef __cplusplus -} -#endif - -#endif /* ecdh.h */ |