mirror of
https://github.com/yuzu-emu/mbedtls.git
synced 2024-11-27 09:14:18 +01:00
d41a95e223
The documentation of HMAC_DRBG erroneously claimed that mbedtls_hmac_drbg_set_entropy_len() had an impact on the initial seeding. This is in fact not the case: mbedtls_hmac_drbg_seed() forces the entropy length to its chosen value. Fix the documentation.
428 lines
17 KiB
C
428 lines
17 KiB
C
/**
|
|
* \file hmac_drbg.h
|
|
*
|
|
* \brief The HMAC_DRBG pseudorandom generator.
|
|
*
|
|
* This module implements the HMAC_DRBG pseudorandom generator described
|
|
* in <em>NIST SP 800-90A: Recommendation for Random Number Generation Using
|
|
* Deterministic Random Bit Generators</em>.
|
|
*/
|
|
/*
|
|
* Copyright (C) 2006-2019, 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_HMAC_DRBG_H
|
|
#define MBEDTLS_HMAC_DRBG_H
|
|
|
|
#if !defined(MBEDTLS_CONFIG_FILE)
|
|
#include "config.h"
|
|
#else
|
|
#include MBEDTLS_CONFIG_FILE
|
|
#endif
|
|
|
|
#include "md.h"
|
|
|
|
#if defined(MBEDTLS_THREADING_C)
|
|
#include "threading.h"
|
|
#endif
|
|
|
|
/*
|
|
* Error codes
|
|
*/
|
|
#define MBEDTLS_ERR_HMAC_DRBG_REQUEST_TOO_BIG -0x0003 /**< Too many random requested in single call. */
|
|
#define MBEDTLS_ERR_HMAC_DRBG_INPUT_TOO_BIG -0x0005 /**< Input too large (Entropy + additional). */
|
|
#define MBEDTLS_ERR_HMAC_DRBG_FILE_IO_ERROR -0x0007 /**< Read/write error in file. */
|
|
#define MBEDTLS_ERR_HMAC_DRBG_ENTROPY_SOURCE_FAILED -0x0009 /**< The entropy source failed. */
|
|
|
|
/**
|
|
* \name SECTION: Module settings
|
|
*
|
|
* The configuration options you can set for this module are in this section.
|
|
* Either change them in config.h or define them on the compiler command line.
|
|
* \{
|
|
*/
|
|
|
|
#if !defined(MBEDTLS_HMAC_DRBG_RESEED_INTERVAL)
|
|
#define MBEDTLS_HMAC_DRBG_RESEED_INTERVAL 10000 /**< Interval before reseed is performed by default */
|
|
#endif
|
|
|
|
#if !defined(MBEDTLS_HMAC_DRBG_MAX_INPUT)
|
|
#define MBEDTLS_HMAC_DRBG_MAX_INPUT 256 /**< Maximum number of additional input bytes */
|
|
#endif
|
|
|
|
#if !defined(MBEDTLS_HMAC_DRBG_MAX_REQUEST)
|
|
#define MBEDTLS_HMAC_DRBG_MAX_REQUEST 1024 /**< Maximum number of requested bytes per call */
|
|
#endif
|
|
|
|
#if !defined(MBEDTLS_HMAC_DRBG_MAX_SEED_INPUT)
|
|
#define MBEDTLS_HMAC_DRBG_MAX_SEED_INPUT 384 /**< Maximum size of (re)seed buffer */
|
|
#endif
|
|
|
|
/* \} name SECTION: Module settings */
|
|
|
|
#define MBEDTLS_HMAC_DRBG_PR_OFF 0x55555555 /**< No prediction resistance */
|
|
#define MBEDTLS_HMAC_DRBG_PR_ON 0x2AAAAAAA /**< Prediction resistance enabled */
|
|
|
|
#ifdef __cplusplus
|
|
extern "C" {
|
|
#endif
|
|
|
|
/**
|
|
* HMAC_DRBG context.
|
|
*/
|
|
typedef struct mbedtls_hmac_drbg_context
|
|
{
|
|
/* Working state: the key K is not stored explicitly,
|
|
* but is implied by the HMAC context */
|
|
mbedtls_md_context_t md_ctx; /*!< HMAC context (inc. K) */
|
|
unsigned char V[MBEDTLS_MD_MAX_SIZE]; /*!< V in the spec */
|
|
int reseed_counter; /*!< reseed counter */
|
|
|
|
/* Administrative state */
|
|
size_t entropy_len; /*!< entropy bytes grabbed on each (re)seed */
|
|
int prediction_resistance; /*!< enable prediction resistance (Automatic
|
|
reseed before every random generation) */
|
|
int reseed_interval; /*!< reseed interval */
|
|
|
|
/* Callbacks */
|
|
int (*f_entropy)(void *, unsigned char *, size_t); /*!< entropy function */
|
|
void *p_entropy; /*!< context for the entropy function */
|
|
|
|
#if defined(MBEDTLS_THREADING_C)
|
|
mbedtls_threading_mutex_t mutex;
|
|
#endif
|
|
} mbedtls_hmac_drbg_context;
|
|
|
|
/**
|
|
* \brief HMAC_DRBG context initialization.
|
|
*
|
|
* This function makes the context ready for mbedtls_hmac_drbg_seed(),
|
|
* mbedtls_hmac_drbg_seed_buf() or mbedtls_hmac_drbg_free().
|
|
*
|
|
* \param ctx HMAC_DRBG context to be initialized.
|
|
*/
|
|
void mbedtls_hmac_drbg_init( mbedtls_hmac_drbg_context *ctx );
|
|
|
|
/**
|
|
* \brief HMAC_DRBG initial seeding.
|
|
*
|
|
* Set the initial seed and set up the entropy source for future reseeds.
|
|
*
|
|
* A typical choice for the \p f_entropy and \p p_entropy parameters is
|
|
* to use the entropy module:
|
|
* - \p f_entropy is mbedtls_entropy_func();
|
|
* - \p p_entropy is an instance of ::mbedtls_entropy_context initialized
|
|
* with mbedtls_entropy_init() (which registers the platform's default
|
|
* entropy sources).
|
|
*
|
|
* You can provide a personalization string in addition to the
|
|
* entropy source, to make this instantiation as unique as possible.
|
|
*
|
|
* \note By default, the security strength as defined by NIST is:
|
|
* - 128 bits if \p md_info is SHA-1;
|
|
* - 192 bits if \p md_info is SHA-224;
|
|
* - 256 bits if \p md_info is SHA-256, SHA-384 or SHA-512.
|
|
* Note that SHA-256 is just as efficient as SHA-224.
|
|
* The security strength can be reduced if a smaller
|
|
* entropy length is set with
|
|
* mbedtls_hmac_drbg_set_entropy_len() afterwards.
|
|
*
|
|
* \note The entropy length for the initial seeding is
|
|
* the security strength (converted from bits to bytes).
|
|
* You can set a different entropy length for subsequent
|
|
* seeding by calling mbedtls_hmac_drbg_set_entropy_len()
|
|
* after this function.
|
|
*
|
|
* \note During the initial seeding, this function calls
|
|
* the entropy source to obtain a nonce
|
|
* whose length is half the entropy length.
|
|
*
|
|
* \param ctx HMAC_DRBG context to be seeded.
|
|
* \param md_info MD algorithm to use for HMAC_DRBG.
|
|
* \param f_entropy The entropy callback, taking as arguments the
|
|
* \p p_entropy context, the buffer to fill, and the
|
|
* length of the buffer.
|
|
* \p f_entropy is always called with a length that is
|
|
* less than or equal to the entropy length.
|
|
* \param p_entropy The entropy context to pass to \p f_entropy.
|
|
* \param custom The personalization string.
|
|
* This can be \c NULL, in which case the personalization
|
|
* string is empty regardless of the value of \p len.
|
|
* \param len The length of the personalization string.
|
|
* This must be at most #MBEDTLS_HMAC_DRBG_MAX_INPUT
|
|
* and also at most
|
|
* #MBEDTLS_HMAC_DRBG_MAX_SEED_INPUT - \p entropy_len * 3 / 2
|
|
* where \p entropy_len is the entropy length
|
|
* described above.
|
|
*
|
|
* \return \c 0 if successful.
|
|
* \return #MBEDTLS_ERR_MD_BAD_INPUT_DATA if \p md_info is
|
|
* invalid.
|
|
* \return #MBEDTLS_ERR_MD_ALLOC_FAILED if there was not enough
|
|
* memory to allocate context data.
|
|
* \return #MBEDTLS_ERR_HMAC_DRBG_ENTROPY_SOURCE_FAILED
|
|
* if the call to \p f_entropy failed.
|
|
*/
|
|
int mbedtls_hmac_drbg_seed( mbedtls_hmac_drbg_context *ctx,
|
|
mbedtls_md_handle_t md_info,
|
|
int (*f_entropy)(void *, unsigned char *, size_t),
|
|
void *p_entropy,
|
|
const unsigned char *custom,
|
|
size_t len );
|
|
|
|
/**
|
|
* \brief Initilisation of simpified HMAC_DRBG (never reseeds).
|
|
*
|
|
* This function is meant for use in algorithms that need a pseudorandom
|
|
* input such as deterministic ECDSA.
|
|
*
|
|
* \param ctx HMAC_DRBG context to be initialised.
|
|
* \param md_info MD algorithm to use for HMAC_DRBG.
|
|
* \param data Concatenation of the initial entropy string and
|
|
* the additional data.
|
|
* \param data_len Length of \p data in bytes.
|
|
*
|
|
* \return \c 0 if successful. or
|
|
* \return #MBEDTLS_ERR_MD_BAD_INPUT_DATA if \p md_info is
|
|
* invalid.
|
|
* \return #MBEDTLS_ERR_MD_ALLOC_FAILED if there was not enough
|
|
* memory to allocate context data.
|
|
*/
|
|
int mbedtls_hmac_drbg_seed_buf( mbedtls_hmac_drbg_context *ctx,
|
|
mbedtls_md_handle_t md_info,
|
|
const unsigned char *data, size_t data_len );
|
|
|
|
/**
|
|
* \brief This function turns prediction resistance on or off.
|
|
* The default value is off.
|
|
*
|
|
* \note If enabled, entropy is gathered at the beginning of
|
|
* every call to mbedtls_hmac_drbg_random_with_add()
|
|
* or mbedtls_hmac_drbg_random().
|
|
* Only use this if your entropy source has sufficient
|
|
* throughput.
|
|
*
|
|
* \param ctx The HMAC_DRBG context.
|
|
* \param resistance #MBEDTLS_HMAC_DRBG_PR_ON or #MBEDTLS_HMAC_DRBG_PR_OFF.
|
|
*/
|
|
void mbedtls_hmac_drbg_set_prediction_resistance( mbedtls_hmac_drbg_context *ctx,
|
|
int resistance );
|
|
|
|
/**
|
|
* \brief This function sets the amount of entropy grabbed on each
|
|
* reseed.
|
|
*
|
|
* The default value is set by mbedtls_hmac_drbg_seed().
|
|
*
|
|
* \note mbedtls_hmac_drbg_seed() always sets the entropy length
|
|
* to the default value based on the chosen MD algorithm,
|
|
* so this function only has an effect if it is called
|
|
* after mbedtls_hmac_drbg_seed().
|
|
*
|
|
* \param ctx The HMAC_DRBG context.
|
|
* \param len The amount of entropy to grab, in bytes.
|
|
*/
|
|
void mbedtls_hmac_drbg_set_entropy_len( mbedtls_hmac_drbg_context *ctx,
|
|
size_t len );
|
|
|
|
/**
|
|
* \brief Set the reseed interval.
|
|
*
|
|
* The reseed interval is the number of calls to mbedtls_hmac_drbg_random()
|
|
* or mbedtls_hmac_drbg_random_with_add() after which the entropy function
|
|
* is called again.
|
|
*
|
|
* The default value is #MBEDTLS_HMAC_DRBG_RESEED_INTERVAL.
|
|
*
|
|
* \param ctx The HMAC_DRBG context.
|
|
* \param interval The reseed interval.
|
|
*/
|
|
void mbedtls_hmac_drbg_set_reseed_interval( mbedtls_hmac_drbg_context *ctx,
|
|
int interval );
|
|
|
|
/**
|
|
* \brief This function updates the state of the HMAC_DRBG context.
|
|
*
|
|
* \param ctx The HMAC_DRBG context.
|
|
* \param additional The data to update the state with.
|
|
* If this is \c NULL, there is no additional data.
|
|
* \param add_len Length of \p additional in bytes.
|
|
* Unused if \p additional is \c NULL.
|
|
*
|
|
* \return \c 0 on success, or an error from the underlying
|
|
* hash calculation or
|
|
* MBEDTLS_ERR_PLATFORM_FAULT_DETECTED.
|
|
*/
|
|
int mbedtls_hmac_drbg_update_ret( mbedtls_hmac_drbg_context *ctx,
|
|
const unsigned char *additional, size_t add_len );
|
|
|
|
/**
|
|
* \brief This function reseeds the HMAC_DRBG context, that is
|
|
* extracts data from the entropy source.
|
|
*
|
|
* \param ctx The HMAC_DRBG context.
|
|
* \param additional Additional data to add to the state.
|
|
* If this is \c NULL, there is no additional data
|
|
* and \p len should be \c 0.
|
|
* \param len The length of the additional data.
|
|
* This must be at most #MBEDTLS_HMAC_DRBG_MAX_INPUT
|
|
* and also at most
|
|
* #MBEDTLS_HMAC_DRBG_MAX_SEED_INPUT - \p entropy_len
|
|
* where \p entropy_len is the entropy length
|
|
* (see mbedtls_hmac_drbg_set_entropy_len()).
|
|
*
|
|
* \return \c 0 if successful.
|
|
* \return #MBEDTLS_ERR_HMAC_DRBG_ENTROPY_SOURCE_FAILED
|
|
* if a call to the entropy function failed.
|
|
*/
|
|
int mbedtls_hmac_drbg_reseed( mbedtls_hmac_drbg_context *ctx,
|
|
const unsigned char *additional, size_t len );
|
|
|
|
/**
|
|
* \brief This function updates an HMAC_DRBG instance with additional
|
|
* data and uses it to generate random data.
|
|
*
|
|
* This function automatically reseeds if the reseed counter is exceeded
|
|
* or prediction resistance is enabled.
|
|
*
|
|
* \param p_rng The HMAC_DRBG context. This must be a pointer to a
|
|
* #mbedtls_hmac_drbg_context structure.
|
|
* \param output The buffer to fill.
|
|
* \param output_len The length of the buffer in bytes.
|
|
* This must be at most #MBEDTLS_HMAC_DRBG_MAX_REQUEST.
|
|
* \param additional Additional data to update with.
|
|
* If this is \c NULL, there is no additional data
|
|
* and \p add_len should be \c 0.
|
|
* \param add_len The length of the additional data.
|
|
* This must be at most #MBEDTLS_HMAC_DRBG_MAX_INPUT.
|
|
*
|
|
* \return \c 0 if successful.
|
|
* \return #MBEDTLS_ERR_HMAC_DRBG_ENTROPY_SOURCE_FAILED
|
|
* if a call to the entropy source failed.
|
|
* \return #MBEDTLS_ERR_HMAC_DRBG_REQUEST_TOO_BIG if
|
|
* \p output_len > #MBEDTLS_HMAC_DRBG_MAX_REQUEST.
|
|
* \return #MBEDTLS_ERR_HMAC_DRBG_INPUT_TOO_BIG if
|
|
* \p add_len > #MBEDTLS_HMAC_DRBG_MAX_INPUT.
|
|
* \return #MBEDTLS_ERR_PLATFORM_FAULT_DETECTED if
|
|
* a logical fault is detected.
|
|
*/
|
|
int mbedtls_hmac_drbg_random_with_add( void *p_rng,
|
|
unsigned char *output, size_t output_len,
|
|
const unsigned char *additional,
|
|
size_t add_len );
|
|
|
|
/**
|
|
* \brief This function uses HMAC_DRBG to generate random data.
|
|
*
|
|
* This function automatically reseeds if the reseed counter is exceeded
|
|
* or prediction resistance is enabled.
|
|
*
|
|
* \param p_rng The HMAC_DRBG context. This must be a pointer to a
|
|
* #mbedtls_hmac_drbg_context structure.
|
|
* \param output The buffer to fill.
|
|
* \param out_len The length of the buffer in bytes.
|
|
* This must be at most #MBEDTLS_HMAC_DRBG_MAX_REQUEST.
|
|
*
|
|
* \return \c 0 if successful.
|
|
* \return #MBEDTLS_ERR_HMAC_DRBG_ENTROPY_SOURCE_FAILED
|
|
* if a call to the entropy source failed.
|
|
* \return #MBEDTLS_ERR_HMAC_DRBG_REQUEST_TOO_BIG if
|
|
* \p out_len > #MBEDTLS_HMAC_DRBG_MAX_REQUEST.
|
|
* \return #MBEDTLS_ERR_PLATFORM_FAULT_DETECTED if
|
|
* a logical fault is detected.
|
|
*/
|
|
int mbedtls_hmac_drbg_random( void *p_rng, unsigned char *output, size_t out_len );
|
|
|
|
/**
|
|
* \brief Free an HMAC_DRBG context
|
|
*
|
|
* \param ctx The HMAC_DRBG context to free.
|
|
*/
|
|
void mbedtls_hmac_drbg_free( mbedtls_hmac_drbg_context *ctx );
|
|
|
|
#if ! defined(MBEDTLS_DEPRECATED_REMOVED)
|
|
#if defined(MBEDTLS_DEPRECATED_WARNING)
|
|
#define MBEDTLS_DEPRECATED __attribute__((deprecated))
|
|
#else
|
|
#define MBEDTLS_DEPRECATED
|
|
#endif
|
|
/**
|
|
* \brief This function updates the state of the HMAC_DRBG context.
|
|
*
|
|
* \deprecated Superseded by mbedtls_hmac_drbg_update_ret()
|
|
* in 2.16.0.
|
|
*
|
|
* \param ctx The HMAC_DRBG context.
|
|
* \param additional The data to update the state with.
|
|
* If this is \c NULL, there is no additional data.
|
|
* \param add_len Length of \p additional in bytes.
|
|
* Unused if \p additional is \c NULL.
|
|
*/
|
|
MBEDTLS_DEPRECATED void mbedtls_hmac_drbg_update(
|
|
mbedtls_hmac_drbg_context *ctx,
|
|
const unsigned char *additional, size_t add_len );
|
|
#undef MBEDTLS_DEPRECATED
|
|
#endif /* !MBEDTLS_DEPRECATED_REMOVED */
|
|
|
|
#if defined(MBEDTLS_FS_IO)
|
|
/**
|
|
* \brief This function writes a seed file.
|
|
*
|
|
* \param ctx The HMAC_DRBG context.
|
|
* \param path The name of the file.
|
|
*
|
|
* \return \c 0 on success.
|
|
* \return #MBEDTLS_ERR_HMAC_DRBG_FILE_IO_ERROR on file error.
|
|
* \return #MBEDTLS_ERR_HMAC_DRBG_ENTROPY_SOURCE_FAILED on reseed
|
|
* failure.
|
|
*/
|
|
int mbedtls_hmac_drbg_write_seed_file( mbedtls_hmac_drbg_context *ctx, const char *path );
|
|
|
|
/**
|
|
* \brief This function reads and updates a seed file. The seed
|
|
* is added to this instance.
|
|
*
|
|
* \param ctx The HMAC_DRBG context.
|
|
* \param path The name of the file.
|
|
*
|
|
* \return \c 0 on success.
|
|
* \return #MBEDTLS_ERR_HMAC_DRBG_FILE_IO_ERROR on file error.
|
|
* \return #MBEDTLS_ERR_HMAC_DRBG_ENTROPY_SOURCE_FAILED on
|
|
* reseed failure.
|
|
* \return #MBEDTLS_ERR_HMAC_DRBG_INPUT_TOO_BIG if the existing
|
|
* seed file is too large.
|
|
*/
|
|
int mbedtls_hmac_drbg_update_seed_file( mbedtls_hmac_drbg_context *ctx, const char *path );
|
|
#endif /* MBEDTLS_FS_IO */
|
|
|
|
|
|
#if defined(MBEDTLS_SELF_TEST)
|
|
/**
|
|
* \brief The HMAC_DRBG Checkup routine.
|
|
*
|
|
* \return \c 0 if successful.
|
|
* \return \c 1 if the test failed.
|
|
*/
|
|
int mbedtls_hmac_drbg_self_test( int verbose );
|
|
#endif
|
|
|
|
#ifdef __cplusplus
|
|
}
|
|
#endif
|
|
|
|
#endif /* hmac_drbg.h */
|