| /** |
| * \file ecdsa.h |
| * |
| * \brief The Elliptic Curve Digital Signature Algorithm (ECDSA). |
| * |
| * ECDSA is defined in <em>Standards for Efficient Cryptography Group (SECG): |
| * SEC1 Elliptic Curve Cryptography</em>. |
| * The use of ECDSA for TLS is defined in <em>RFC-4492: Elliptic Curve |
| * Cryptography (ECC) Cipher Suites for Transport Layer Security (TLS)</em>. |
| * |
| */ |
| /* |
| * Copyright (C) 2006-2018, Arm Limited (or its affiliates), 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_ECDSA_H |
| #define MBEDTLS_ECDSA_H |
| |
| #include "ecp.h" |
| #include "md.h" |
| |
| /* |
| * RFC-4492 page 20: |
| * |
| * Ecdsa-Sig-Value ::= SEQUENCE { |
| * r INTEGER, |
| * s INTEGER |
| * } |
| * |
| * Size is at most |
| * 1 (tag) + 1 (len) + 1 (initial 0) + ECP_MAX_BYTES for each of r and s, |
| * twice that + 1 (tag) + 2 (len) for the sequence |
| * (assuming ECP_MAX_BYTES is less than 126 for r and s, |
| * and less than 124 (total len <= 255) for the sequence) |
| */ |
| #if MBEDTLS_ECP_MAX_BYTES > 124 |
| #error "MBEDTLS_ECP_MAX_BYTES bigger than expected, please fix MBEDTLS_ECDSA_MAX_LEN" |
| #endif |
| /** The maximal size of an ECDSA signature in Bytes. */ |
| #define MBEDTLS_ECDSA_MAX_LEN ( 3 + 2 * ( 3 + MBEDTLS_ECP_MAX_BYTES ) ) |
| |
| /** |
| * \brief The ECDSA context structure. |
| */ |
| typedef mbedtls_ecp_keypair mbedtls_ecdsa_context; |
| |
| #ifdef __cplusplus |
| extern "C" { |
| #endif |
| |
| /** |
| * \brief This function computes the ECDSA signature of a |
| * previously-hashed message. |
| * |
| * \note The deterministic version is usually preferred. |
| * |
| * \param grp The ECP group. |
| * \param r The first output integer. |
| * \param s The second output integer. |
| * \param d The private signing key. |
| * \param buf The message hash. |
| * \param blen The length of \p buf. |
| * \param f_rng The RNG function. |
| * \param p_rng The RNG parameter. |
| * |
| * \note If the bitlength of the message hash is larger than the |
| * bitlength of the group order, then the hash is truncated |
| * as defined in <em>Standards for Efficient Cryptography Group |
| * (SECG): SEC1 Elliptic Curve Cryptography</em>, section |
| * 4.1.3, step 5. |
| * |
| * \return \c 0 on success, or an \c MBEDTLS_ERR_ECP_XXX |
| * or \c MBEDTLS_MPI_XXX error code on failure. |
| * |
| * \see ecp.h |
| */ |
| int mbedtls_ecdsa_sign( mbedtls_ecp_group *grp, mbedtls_mpi *r, mbedtls_mpi *s, |
| const mbedtls_mpi *d, const unsigned char *buf, size_t blen, |
| int (*f_rng)(void *, unsigned char *, size_t), void *p_rng ); |
| |
| #if defined(MBEDTLS_ECDSA_DETERMINISTIC) |
| /** |
| * \brief This function computes the ECDSA signature of a |
| * previously-hashed message, deterministic version. |
| * For more information, see <em>RFC-6979: Deterministic |
| * Usage of the Digital Signature Algorithm (DSA) and Elliptic |
| * Curve Digital Signature Algorithm (ECDSA)</em>. |
| * |
| * \param grp The ECP group. |
| * \param r The first output integer. |
| * \param s The second output integer. |
| * \param d The private signing key. |
| * \param buf The message hash. |
| * \param blen The length of \p buf. |
| * \param md_alg The MD algorithm used to hash the message. |
| * |
| * \note If the bitlength of the message hash is larger than the |
| * bitlength of the group order, then the hash is truncated as |
| * defined in <em>Standards for Efficient Cryptography Group |
| * (SECG): SEC1 Elliptic Curve Cryptography</em>, section |
| * 4.1.3, step 5. |
| * |
| * \return \c 0 on success, |
| * or an \c MBEDTLS_ERR_ECP_XXX or \c MBEDTLS_MPI_XXX |
| * error code on failure. |
| * |
| * \see ecp.h |
| */ |
| int mbedtls_ecdsa_sign_det( mbedtls_ecp_group *grp, mbedtls_mpi *r, mbedtls_mpi *s, |
| const mbedtls_mpi *d, const unsigned char *buf, size_t blen, |
| mbedtls_md_type_t md_alg ); |
| #endif /* MBEDTLS_ECDSA_DETERMINISTIC */ |
| |
| /** |
| * \brief This function verifies the ECDSA signature of a |
| * previously-hashed message. |
| * |
| * \param grp The ECP group. |
| * \param buf The message hash. |
| * \param blen The length of \p buf. |
| * \param Q The public key to use for verification. |
| * \param r The first integer of the signature. |
| * \param s The second integer of the signature. |
| * |
| * \note If the bitlength of the message hash is larger than the |
| * bitlength of the group order, then the hash is truncated as |
| * defined in <em>Standards for Efficient Cryptography Group |
| * (SECG): SEC1 Elliptic Curve Cryptography</em>, section |
| * 4.1.4, step 3. |
| * |
| * \return \c 0 on success, |
| * #MBEDTLS_ERR_ECP_BAD_INPUT_DATA if signature is invalid, |
| * or an \c MBEDTLS_ERR_ECP_XXX or \c MBEDTLS_MPI_XXX |
| * error code on failure for any other reason. |
| * |
| * \see ecp.h |
| */ |
| int mbedtls_ecdsa_verify( mbedtls_ecp_group *grp, |
| const unsigned char *buf, size_t blen, |
| const mbedtls_ecp_point *Q, const mbedtls_mpi *r, const mbedtls_mpi *s); |
| |
| /** |
| * \brief This function computes the ECDSA signature and writes it |
| * to a buffer, serialized as defined in <em>RFC-4492: |
| * Elliptic Curve Cryptography (ECC) Cipher Suites for |
| * Transport Layer Security (TLS)</em>. |
| * |
| * \warning It is not thread-safe to use the same context in |
| * multiple threads. |
| * |
| * \note The deterministic version is used if |
| * #MBEDTLS_ECDSA_DETERMINISTIC is defined. For more |
| * information, see <em>RFC-6979: Deterministic Usage |
| * of the Digital Signature Algorithm (DSA) and Elliptic |
| * Curve Digital Signature Algorithm (ECDSA)</em>. |
| * |
| * \param ctx The ECDSA context. |
| * \param md_alg The message digest that was used to hash the message. |
| * \param hash The message hash. |
| * \param hlen The length of the hash. |
| * \param sig The buffer that holds the signature. |
| * \param slen The length of the signature written. |
| * \param f_rng The RNG function. |
| * \param p_rng The RNG parameter. |
| * |
| * \note The \p sig buffer must be at least twice as large as the |
| * size of the curve used, plus 9. For example, 73 Bytes if |
| * a 256-bit curve is used. A buffer length of |
| * #MBEDTLS_ECDSA_MAX_LEN is always safe. |
| * |
| * \note If the bitlength of the message hash is larger than the |
| * bitlength of the group order, then the hash is truncated as |
| * defined in <em>Standards for Efficient Cryptography Group |
| * (SECG): SEC1 Elliptic Curve Cryptography</em>, section |
| * 4.1.3, step 5. |
| * |
| * \return \c 0 on success, |
| * or an \c MBEDTLS_ERR_ECP_XXX, \c MBEDTLS_ERR_MPI_XXX or |
| * \c MBEDTLS_ERR_ASN1_XXX error code on failure. |
| * |
| * \see ecp.h |
| */ |
| int mbedtls_ecdsa_write_signature( mbedtls_ecdsa_context *ctx, mbedtls_md_type_t md_alg, |
| const unsigned char *hash, size_t hlen, |
| unsigned char *sig, size_t *slen, |
| int (*f_rng)(void *, unsigned char *, size_t), |
| void *p_rng ); |
| |
| #if defined(MBEDTLS_ECDSA_DETERMINISTIC) |
| #if ! defined(MBEDTLS_DEPRECATED_REMOVED) |
| #if defined(MBEDTLS_DEPRECATED_WARNING) |
| #define MBEDTLS_DEPRECATED __attribute__((deprecated)) |
| #else |
| #define MBEDTLS_DEPRECATED |
| #endif |
| /** |
| * \brief This function computes an ECDSA signature and writes it to a buffer, |
| * serialized as defined in <em>RFC-4492: Elliptic Curve Cryptography |
| * (ECC) Cipher Suites for Transport Layer Security (TLS)</em>. |
| * |
| * The deterministic version is defined in <em>RFC-6979: |
| * Deterministic Usage of the Digital Signature Algorithm (DSA) and |
| * Elliptic Curve Digital Signature Algorithm (ECDSA)</em>. |
| * |
| * \warning It is not thread-safe to use the same context in |
| * multiple threads. |
| |
| * |
| * \deprecated Superseded by mbedtls_ecdsa_write_signature() in 2.0.0 |
| * |
| * \param ctx The ECDSA context. |
| * \param hash The Message hash. |
| * \param hlen The length of the hash. |
| * \param sig The buffer that holds the signature. |
| * \param slen The length of the signature written. |
| * \param md_alg The MD algorithm used to hash the message. |
| * |
| * \note The \p sig buffer must be at least twice as large as the |
| * size of the curve used, plus 9. For example, 73 Bytes if a |
| * 256-bit curve is used. A buffer length of |
| * #MBEDTLS_ECDSA_MAX_LEN is always safe. |
| * |
| * \note If the bitlength of the message hash is larger than the |
| * bitlength of the group order, then the hash is truncated as |
| * defined in <em>Standards for Efficient Cryptography Group |
| * (SECG): SEC1 Elliptic Curve Cryptography</em>, section |
| * 4.1.3, step 5. |
| * |
| * \return \c 0 on success, |
| * or an \c MBEDTLS_ERR_ECP_XXX, \c MBEDTLS_ERR_MPI_XXX or |
| * \c MBEDTLS_ERR_ASN1_XXX error code on failure. |
| * |
| * \see ecp.h |
| */ |
| int mbedtls_ecdsa_write_signature_det( mbedtls_ecdsa_context *ctx, |
| const unsigned char *hash, size_t hlen, |
| unsigned char *sig, size_t *slen, |
| mbedtls_md_type_t md_alg ) MBEDTLS_DEPRECATED; |
| #undef MBEDTLS_DEPRECATED |
| #endif /* MBEDTLS_DEPRECATED_REMOVED */ |
| #endif /* MBEDTLS_ECDSA_DETERMINISTIC */ |
| |
| /** |
| * \brief This function reads and verifies an ECDSA signature. |
| * |
| * \param ctx The ECDSA context. |
| * \param hash The message hash. |
| * \param hlen The size of the hash. |
| * \param sig The signature to read and verify. |
| * \param slen The size of \p sig. |
| * |
| * \note If the bitlength of the message hash is larger than the |
| * bitlength of the group order, then the hash is truncated as |
| * defined in <em>Standards for Efficient Cryptography Group |
| * (SECG): SEC1 Elliptic Curve Cryptography</em>, section |
| * 4.1.4, step 3. |
| * |
| * \return \c 0 on success, |
| * #MBEDTLS_ERR_ECP_BAD_INPUT_DATA if signature is invalid, |
| * #MBEDTLS_ERR_ECP_SIG_LEN_MISMATCH if the signature is |
| * valid but its actual length is less than \p siglen, |
| * or an \c MBEDTLS_ERR_ECP_XXX or \c MBEDTLS_ERR_MPI_XXX |
| * error code on failure for any other reason. |
| * |
| * \see ecp.h |
| */ |
| int mbedtls_ecdsa_read_signature( mbedtls_ecdsa_context *ctx, |
| const unsigned char *hash, size_t hlen, |
| const unsigned char *sig, size_t slen ); |
| |
| /** |
| * \brief This function generates an ECDSA keypair on the given curve. |
| * |
| * \param ctx The ECDSA context to store the keypair in. |
| * \param gid The elliptic curve to use. One of the various |
| * \c MBEDTLS_ECP_DP_XXX macros depending on configuration. |
| * \param f_rng The RNG function. |
| * \param p_rng The RNG parameter. |
| * |
| * \return \c 0 on success, or an \c MBEDTLS_ERR_ECP_XXX code on |
| * failure. |
| * |
| * \see ecp.h |
| */ |
| int mbedtls_ecdsa_genkey( mbedtls_ecdsa_context *ctx, mbedtls_ecp_group_id gid, |
| int (*f_rng)(void *, unsigned char *, size_t), void *p_rng ); |
| |
| /** |
| * \brief This function sets an ECDSA context from an EC key pair. |
| * |
| * \param ctx The ECDSA context to set. |
| * \param key The EC key to use. |
| * |
| * \return \c 0 on success, or an \c MBEDTLS_ERR_ECP_XXX code on |
| * failure. |
| * |
| * \see ecp.h |
| */ |
| int mbedtls_ecdsa_from_keypair( mbedtls_ecdsa_context *ctx, const mbedtls_ecp_keypair *key ); |
| |
| /** |
| * \brief This function initializes an ECDSA context. |
| * |
| * \param ctx The ECDSA context to initialize. |
| */ |
| void mbedtls_ecdsa_init( mbedtls_ecdsa_context *ctx ); |
| |
| /** |
| * \brief This function frees an ECDSA context. |
| * |
| * \param ctx The ECDSA context to free. |
| */ |
| void mbedtls_ecdsa_free( mbedtls_ecdsa_context *ctx ); |
| |
| #ifdef __cplusplus |
| } |
| #endif |
| |
| #endif /* ecdsa.h */ |