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Diffstat (limited to 'vendor/mbedtls/hkdf.h')
| -rw-r--r-- | vendor/mbedtls/hkdf.h | 124 |
1 files changed, 124 insertions, 0 deletions
diff --git a/vendor/mbedtls/hkdf.h b/vendor/mbedtls/hkdf.h new file mode 100644 index 0000000..930e93f --- /dev/null +++ b/vendor/mbedtls/hkdf.h @@ -0,0 +1,124 @@ +/** + * \file hkdf.h + * + * \brief This file contains the HKDF interface. + * + * The HMAC-based Extract-and-Expand Key Derivation Function (HKDF) is + * specified by RFC 5869. + */ +/* + * Copyright The Mbed TLS Contributors + * SPDX-License-Identifier: Apache-2.0 OR GPL-2.0-or-later + */ +#ifndef MBEDTLS_HKDF_H +#define MBEDTLS_HKDF_H + +#include "mbedtls/build_info.h" + +#include "mbedtls/md.h" + +/** + * \name HKDF Error codes + * \{ + */ +/** Bad input parameters to function. */ +#define MBEDTLS_ERR_HKDF_BAD_INPUT_DATA -0x5F80 +/** \} name */ + +#ifdef __cplusplus +extern "C" { +#endif + +/** + * \brief This is the HMAC-based Extract-and-Expand Key Derivation Function + * (HKDF). + * + * \param md A hash function; md.size denotes the length of the hash + * function output in bytes. + * \param salt An optional salt value (a non-secret random value); + * if the salt is not provided, a string of all zeros of + * md.size length is used as the salt. + * \param salt_len The length in bytes of the optional \p salt. + * \param ikm The input keying material. + * \param ikm_len The length in bytes of \p ikm. + * \param info An optional context and application specific information + * string. This can be a zero-length string. + * \param info_len The length of \p info in bytes. + * \param okm The output keying material of \p okm_len bytes. + * \param okm_len The length of the output keying material in bytes. This + * must be less than or equal to 255 * md.size bytes. + * + * \return 0 on success. + * \return #MBEDTLS_ERR_HKDF_BAD_INPUT_DATA when the parameters are invalid. + * \return An MBEDTLS_ERR_MD_* error for errors returned from the underlying + * MD layer. + */ +int mbedtls_hkdf(const mbedtls_md_info_t *md, const unsigned char *salt, + size_t salt_len, const unsigned char *ikm, size_t ikm_len, + const unsigned char *info, size_t info_len, + unsigned char *okm, size_t okm_len); + +/** + * \brief Take the input keying material \p ikm and extract from it a + * fixed-length pseudorandom key \p prk. + * + * \warning This function should only be used if the security of it has been + * studied and established in that particular context (eg. TLS 1.3 + * key schedule). For standard HKDF security guarantees use + * \c mbedtls_hkdf instead. + * + * \param md A hash function; md.size denotes the length of the + * hash function output in bytes. + * \param salt An optional salt value (a non-secret random value); + * if the salt is not provided, a string of all zeros + * of md.size length is used as the salt. + * \param salt_len The length in bytes of the optional \p salt. + * \param ikm The input keying material. + * \param ikm_len The length in bytes of \p ikm. + * \param[out] prk A pseudorandom key of at least md.size bytes. + * + * \return 0 on success. + * \return #MBEDTLS_ERR_HKDF_BAD_INPUT_DATA when the parameters are invalid. + * \return An MBEDTLS_ERR_MD_* error for errors returned from the underlying + * MD layer. + */ +int mbedtls_hkdf_extract(const mbedtls_md_info_t *md, + const unsigned char *salt, size_t salt_len, + const unsigned char *ikm, size_t ikm_len, + unsigned char *prk); + +/** + * \brief Expand the supplied \p prk into several additional pseudorandom + * keys, which is the output of the HKDF. + * + * \warning This function should only be used if the security of it has been + * studied and established in that particular context (eg. TLS 1.3 + * key schedule). For standard HKDF security guarantees use + * \c mbedtls_hkdf instead. + * + * \param md A hash function; md.size denotes the length of the hash + * function output in bytes. + * \param prk A pseudorandom key of at least md.size bytes. \p prk is + * usually the output from the HKDF extract step. + * \param prk_len The length in bytes of \p prk. + * \param info An optional context and application specific information + * string. This can be a zero-length string. + * \param info_len The length of \p info in bytes. + * \param okm The output keying material of \p okm_len bytes. + * \param okm_len The length of the output keying material in bytes. This + * must be less than or equal to 255 * md.size bytes. + * + * \return 0 on success. + * \return #MBEDTLS_ERR_HKDF_BAD_INPUT_DATA when the parameters are invalid. + * \return An MBEDTLS_ERR_MD_* error for errors returned from the underlying + * MD layer. + */ +int mbedtls_hkdf_expand(const mbedtls_md_info_t *md, const unsigned char *prk, + size_t prk_len, const unsigned char *info, + size_t info_len, unsigned char *okm, size_t okm_len); + +#ifdef __cplusplus +} +#endif + +#endif /* hkdf.h */ |