| /** | |
| * \file ecjpake.h | |
| * | |
| * \brief Elliptic curve J-PAKE | |
| */ | |
| /* | |
| * Copyright (C) 2006-2015, ARM Limited, All Rights Reserved | |
| * SPDX-License-Identifier: Apache-2.0 | |
| * | |
| * Licensed under the Apache License, Version 2.0 (the "License"); you may | |
| * not use this file except in compliance with the License. | |
| * You may obtain a copy of the License at | |
| * | |
| * http://www.apache.org/licenses/LICENSE-2.0 | |
| * | |
| * Unless required by applicable law or agreed to in writing, software | |
| * distributed under the License is distributed on an "AS IS" BASIS, WITHOUT | |
| * WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. | |
| * See the License for the specific language governing permissions and | |
| * limitations under the License. | |
| * | |
| * This file is part of mbed TLS (https://tls.mbed.org) | |
| */ | |
| #ifndef MBEDTLS_ECJPAKE_H | |
| #define MBEDTLS_ECJPAKE_H | |
| /* | |
| * J-PAKE is a password-authenticated key exchange that allows deriving a | |
| * strong shared secret from a (potentially low entropy) pre-shared | |
| * passphrase, with forward secrecy and mutual authentication. | |
| * https://en.wikipedia.org/wiki/Password_Authenticated_Key_Exchange_by_Juggling | |
| * | |
| * This file implements the Elliptic Curve variant of J-PAKE, | |
| * as defined in Chapter 7.4 of the Thread v1.0 Specification, | |
| * available to members of the Thread Group http://threadgroup.org/ | |
| * | |
| * As the J-PAKE algorithm is inherently symmetric, so is our API. | |
| * Each party needs to send its first round message, in any order, to the | |
| * other party, then each sends its second round message, in any order. | |
| * The payloads are serialized in a way suitable for use in TLS, but could | |
| * also be use outside TLS. | |
| */ | |
| #if !defined(MBEDTLS_CONFIG_FILE) | |
| #include "config.h" | |
| #else | |
| #include MBEDTLS_CONFIG_FILE | |
| #endif | |
| #include "ecp.h" | |
| #include "md.h" | |
| #ifdef __cplusplus | |
| extern "C" { | |
| #endif | |
| /** | |
| * Roles in the EC J-PAKE exchange | |
| */ | |
| typedef enum { | |
| MBEDTLS_ECJPAKE_CLIENT = 0, /**< Client */ | |
| MBEDTLS_ECJPAKE_SERVER, /**< Server */ | |
| } mbedtls_ecjpake_role; | |
| #if !defined(MBEDTLS_ECJPAKE_ALT) | |
| /** | |
| * EC J-PAKE context structure. | |
| * | |
| * J-PAKE is a symmetric protocol, except for the identifiers used in | |
| * Zero-Knowledge Proofs, and the serialization of the second message | |
| * (KeyExchange) as defined by the Thread spec. | |
| * | |
| * In order to benefit from this symmetry, we choose a different naming | |
| * convetion from the Thread v1.0 spec. Correspondance is indicated in the | |
| * description as a pair C: client name, S: server name | |
| */ | |
| typedef struct mbedtls_ecjpake_context | |
| { | |
| const mbedtls_md_info_t *md_info; /**< Hash to use */ | |
| mbedtls_ecp_group grp; /**< Elliptic curve */ | |
| mbedtls_ecjpake_role role; /**< Are we client or server? */ | |
| int point_format; /**< Format for point export */ | |
| mbedtls_ecp_point Xm1; /**< My public key 1 C: X1, S: X3 */ | |
| mbedtls_ecp_point Xm2; /**< My public key 2 C: X2, S: X4 */ | |
| mbedtls_ecp_point Xp1; /**< Peer public key 1 C: X3, S: X1 */ | |
| mbedtls_ecp_point Xp2; /**< Peer public key 2 C: X4, S: X2 */ | |
| mbedtls_ecp_point Xp; /**< Peer public key C: Xs, S: Xc */ | |
| mbedtls_mpi xm1; /**< My private key 1 C: x1, S: x3 */ | |
| mbedtls_mpi xm2; /**< My private key 2 C: x2, S: x4 */ | |
| mbedtls_mpi s; /**< Pre-shared secret (passphrase) */ | |
| } mbedtls_ecjpake_context; | |
| #else /* MBEDTLS_ECJPAKE_ALT */ | |
| #include "ecjpake_alt.h" | |
| #endif /* MBEDTLS_ECJPAKE_ALT */ | |
| /** | |
| * \brief Initialize an ECJPAKE context. | |
| * | |
| * \param ctx The ECJPAKE context to initialize. | |
| * This must not be \c NULL. | |
| */ | |
| void mbedtls_ecjpake_init( mbedtls_ecjpake_context *ctx ); | |
| /** | |
| * \brief Set up an ECJPAKE context for use. | |
| * | |
| * \note Currently the only values for hash/curve allowed by the | |
| * standard are #MBEDTLS_MD_SHA256/#MBEDTLS_ECP_DP_SECP256R1. | |
| * | |
| * \param ctx The ECJPAKE context to set up. This must be initialized. | |
| * \param role The role of the caller. This must be either | |
| * #MBEDTLS_ECJPAKE_CLIENT or #MBEDTLS_ECJPAKE_SERVER. | |
| * \param hash The identifier of the hash function to use, | |
| * for example #MBEDTLS_MD_SHA256. | |
| * \param curve The identifier of the elliptic curve to use, | |
| * for example #MBEDTLS_ECP_DP_SECP256R1. | |
| * \param secret The pre-shared secret (passphrase). This must be | |
| * a readable buffer of length \p len Bytes. It need | |
| * only be valid for the duration of this call. | |
| * \param len The length of the pre-shared secret \p secret. | |
| * | |
| * \return \c 0 if successful. | |
| * \return A negative error code on failure. | |
| */ | |
| int mbedtls_ecjpake_setup( mbedtls_ecjpake_context *ctx, | |
| mbedtls_ecjpake_role role, | |
| mbedtls_md_type_t hash, | |
| mbedtls_ecp_group_id curve, | |
| const unsigned char *secret, | |
| size_t len ); | |
| /** | |
| * \brief Check if an ECJPAKE context is ready for use. | |
| * | |
| * \param ctx The ECJPAKE context to check. This must be | |
| * initialized. | |
| * | |
| * \return \c 0 if the context is ready for use. | |
| * \return #MBEDTLS_ERR_ECP_BAD_INPUT_DATA otherwise. | |
| */ | |
| int mbedtls_ecjpake_check( const mbedtls_ecjpake_context *ctx ); | |
| /** | |
| * \brief Generate and write the first round message | |
| * (TLS: contents of the Client/ServerHello extension, | |
| * excluding extension type and length bytes). | |
| * | |
| * \param ctx The ECJPAKE context to use. This must be | |
| * initialized and set up. | |
| * \param buf The buffer to write the contents to. This must be a | |
| * writable buffer of length \p len Bytes. | |
| * \param len The length of \p buf in Bytes. | |
| * \param olen The address at which to store the total number | |
| * of Bytes written to \p buf. This must not be \c NULL. | |
| * \param f_rng The RNG function to use. 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 use a context. | |
| * | |
| * \return \c 0 if successful. | |
| * \return A negative error code on failure. | |
| */ | |
| int mbedtls_ecjpake_write_round_one( mbedtls_ecjpake_context *ctx, | |
| unsigned char *buf, size_t len, size_t *olen, | |
| int (*f_rng)(void *, unsigned char *, size_t), | |
| void *p_rng ); | |
| /** | |
| * \brief Read and process the first round message | |
| * (TLS: contents of the Client/ServerHello extension, | |
| * excluding extension type and length bytes). | |
| * | |
| * \param ctx The ECJPAKE context to use. This must be initialized | |
| * and set up. | |
| * \param buf The buffer holding the first round message. This must | |
| * be a readable buffer of length \p len Bytes. | |
| * \param len The length in Bytes of \p buf. | |
| * | |
| * \return \c 0 if successful. | |
| * \return A negative error code on failure. | |
| */ | |
| int mbedtls_ecjpake_read_round_one( mbedtls_ecjpake_context *ctx, | |
| const unsigned char *buf, | |
| size_t len ); | |
| /** | |
| * \brief Generate and write the second round message | |
| * (TLS: contents of the Client/ServerKeyExchange). | |
| * | |
| * \param ctx The ECJPAKE context to use. This must be initialized, | |
| * set up, and already have performed round one. | |
| * \param buf The buffer to write the round two contents to. | |
| * This must be a writable buffer of length \p len Bytes. | |
| * \param len The size of \p buf in Bytes. | |
| * \param olen The address at which to store the total number of Bytes | |
| * written to \p buf. This must not be \c NULL. | |
| * \param f_rng The RNG function to use. 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 use a context. | |
| * | |
| * \return \c 0 if successful. | |
| * \return A negative error code on failure. | |
| */ | |
| int mbedtls_ecjpake_write_round_two( mbedtls_ecjpake_context *ctx, | |
| unsigned char *buf, size_t len, size_t *olen, | |
| int (*f_rng)(void *, unsigned char *, size_t), | |
| void *p_rng ); | |
| /** | |
| * \brief Read and process the second round message | |
| * (TLS: contents of the Client/ServerKeyExchange). | |
| * | |
| * \param ctx The ECJPAKE context to use. This must be initialized | |
| * and set up and already have performed round one. | |
| * \param buf The buffer holding the second round message. This must | |
| * be a readable buffer of length \p len Bytes. | |
| * \param len The length in Bytes of \p buf. | |
| * | |
| * \return \c 0 if successful. | |
| * \return A negative error code on failure. | |
| */ | |
| int mbedtls_ecjpake_read_round_two( mbedtls_ecjpake_context *ctx, | |
| const unsigned char *buf, | |
| size_t len ); | |
| /** | |
| * \brief Derive the shared secret | |
| * (TLS: Pre-Master Secret). | |
| * | |
| * \param ctx The ECJPAKE context to use. This must be initialized, | |
| * set up and have performed both round one and two. | |
| * \param buf The buffer to write the derived secret to. This must | |
| * be a writable buffer of length \p len Bytes. | |
| * \param len The length of \p buf in Bytes. | |
| * \param olen The address at which to store the total number of Bytes | |
| * written to \p buf. This must not be \c NULL. | |
| * \param f_rng The RNG function to use. 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 use a context. | |
| * | |
| * \return \c 0 if successful. | |
| * \return A negative error code on failure. | |
| */ | |
| int mbedtls_ecjpake_derive_secret( mbedtls_ecjpake_context *ctx, | |
| unsigned char *buf, size_t len, size_t *olen, | |
| int (*f_rng)(void *, unsigned char *, size_t), | |
| void *p_rng ); | |
| /** | |
| * \brief This clears an ECJPAKE context and frees any | |
| * embedded data structure. | |
| * | |
| * \param ctx The ECJPAKE 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 ECJPAKE context. | |
| */ | |
| void mbedtls_ecjpake_free( mbedtls_ecjpake_context *ctx ); | |
| #if defined(MBEDTLS_SELF_TEST) | |
| /** | |
| * \brief Checkup routine | |
| * | |
| * \return 0 if successful, or 1 if a test failed | |
| */ | |
| int mbedtls_ecjpake_self_test( int verbose ); | |
| #endif /* MBEDTLS_SELF_TEST */ | |
| #ifdef __cplusplus | |
| } | |
| #endif | |
| #endif /* ecjpake.h */ |