HMAC_DRBG (NIST SP 800-90A) More...

Data Structures
struct	mbedtls_hmac_drbg_context
	HMAC_DRBG context. More...
Functions
void	mbedtls_hmac_drbg_init (mbedtls_hmac_drbg_context *ctx)
	HMAC_DRBG context initialization Makes the context ready for mbedtls_hmac_drbg_seed(), mbedtls_hmac_drbg_seed_buf() or mbedtls_hmac_drbg_free().
int	mbedtls_hmac_drbg_seed (mbedtls_hmac_drbg_context ctx, const mbedtls_md_info_t md_info, int(f_entropy)(void , unsigned char , size_t), void p_entropy, const unsigned char *custom, size_t len)
	HMAC_DRBG initial seeding Seed and setup entropy source for future reseeds.
int	mbedtls_hmac_drbg_seed_buf (mbedtls_hmac_drbg_context ctx, const mbedtls_md_info_t md_info, const unsigned char *data, size_t data_len)
	Initilisation of simpified HMAC_DRBG (never reseeds).
void	mbedtls_hmac_drbg_set_prediction_resistance (mbedtls_hmac_drbg_context *ctx, int resistance)
	Enable / disable prediction resistance (Default: Off)
void	mbedtls_hmac_drbg_set_entropy_len (mbedtls_hmac_drbg_context *ctx, size_t len)
	Set the amount of entropy grabbed on each reseed (Default: given by the security strength, which depends on the hash used, see `mbedtls_hmac_drbg_init()` )
void	mbedtls_hmac_drbg_set_reseed_interval (mbedtls_hmac_drbg_context *ctx, int interval)
	Set the reseed interval (Default: MBEDTLS_HMAC_DRBG_RESEED_INTERVAL)
void	mbedtls_hmac_drbg_update (mbedtls_hmac_drbg_context ctx, const unsigned char additional, size_t add_len)
	HMAC_DRBG update state.
int	mbedtls_hmac_drbg_reseed (mbedtls_hmac_drbg_context ctx, const unsigned char additional, size_t len)
	HMAC_DRBG reseeding (extracts data from entropy source)
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)
	HMAC_DRBG generate random with additional update input.
int	mbedtls_hmac_drbg_random (void p_rng, unsigned char output, size_t out_len)
	HMAC_DRBG generate random.
void	mbedtls_hmac_drbg_free (mbedtls_hmac_drbg_context *ctx)
	Free an HMAC_DRBG context.
int	mbedtls_hmac_drbg_write_seed_file (mbedtls_hmac_drbg_context ctx, const char path)
	Write a seed file.
int	mbedtls_hmac_drbg_update_seed_file (mbedtls_hmac_drbg_context ctx, const char path)
	Read and update a seed file.
int	mbedtls_hmac_drbg_self_test (int verbose)
	Checkup routine.

Detailed Description

HMAC_DRBG (NIST SP 800-90A)

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)

Definition in file hmac_drbg.h.

Function Documentation

void mbedtls_hmac_drbg_free ( mbedtls_hmac_drbg_context * ctx )

Free an HMAC_DRBG context.

Parameters:

ctx	HMAC_DRBG context to free.

Definition at line 332 of file hmac_drbg.c.

void mbedtls_hmac_drbg_init ( mbedtls_hmac_drbg_context * ctx )

HMAC_DRBG context initialization Makes the context ready for mbedtls_hmac_drbg_seed(), mbedtls_hmac_drbg_seed_buf() or mbedtls_hmac_drbg_free().

Parameters:

ctx	HMAC_DRBG context to be initialized

Definition at line 61 of file hmac_drbg.c.

int mbedtls_hmac_drbg_random	(	void *	p_rng,
		unsigned char *	output,
		size_t	out_len
	)

HMAC_DRBG generate random.

Note: Automatically reseeds if reseed_counter is reached or PR is enabled.

Parameters:

p_rng	HMAC_DRBG context
output	Buffer to fill
out_len	Length of the buffer

Returns:: 0 if successful, or MBEDTLS_ERR_HMAC_DRBG_ENTROPY_SOURCE_FAILED, or MBEDTLS_ERR_HMAC_DRBG_REQUEST_TOO_BIG

Definition at line 309 of file hmac_drbg.c.

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
	)

HMAC_DRBG generate random with additional update input.

Note: Automatically reseeds if reseed_counter is reached or PR is enabled.

Parameters:

p_rng	HMAC_DRBG context
output	Buffer to fill
output_len	Length of the buffer
additional	Additional data to update with (can be NULL)
add_len	Length of additional data (can be 0)

Returns:: 0 if successful, or MBEDTLS_ERR_HMAC_DRBG_ENTROPY_SOURCE_FAILED, or MBEDTLS_ERR_HMAC_DRBG_REQUEST_TOO_BIG, or MBEDTLS_ERR_HMAC_DRBG_INPUT_TOO_BIG.

Definition at line 249 of file hmac_drbg.c.

int mbedtls_hmac_drbg_reseed	(	mbedtls_hmac_drbg_context *	ctx,
		const unsigned char *	additional,
		size_t	len
	)

HMAC_DRBG reseeding (extracts data from entropy source)

Parameters:

ctx	HMAC_DRBG context
additional	Additional data to add to state (Can be NULL)
len	Length of additional data

Returns:: 0 if successful, or MBEDTLS_ERR_HMAC_DRBG_ENTROPY_SOURCE_FAILED

Definition at line 126 of file hmac_drbg.c.

int mbedtls_hmac_drbg_seed	(	mbedtls_hmac_drbg_context *	ctx,
		const mbedtls_md_info_t *	md_info,
		int()(void , unsigned char *, size_t)	f_entropy,
		void *	p_entropy,
		const unsigned char *	custom,
		size_t	len
	)

HMAC_DRBG initial seeding Seed and setup entropy source for future reseeds.

Parameters:

ctx	HMAC_DRBG context to be seeded
md_info	MD algorithm to use for HMAC_DRBG
f_entropy	Entropy callback (p_entropy, buffer to fill, buffer length)
p_entropy	Entropy context
custom	Personalization data (Device specific identifiers) (Can be NULL)
len	Length of personalization data

Note:: The "security strength" as defined by NIST is set to: 128 bits if md_alg is SHA-1, 192 bits if md_alg is SHA-224, 256 bits if md_alg is SHA-256 or higher. Note that SHA-256 is just as efficient as SHA-224.

Returns:: 0 if successful, or MBEDTLS_ERR_MD_BAD_INPUT_DATA, or MBEDTLS_ERR_MD_ALLOC_FAILED, or MBEDTLS_ERR_HMAC_DRBG_ENTROPY_SOURCE_FAILED.

Definition at line 167 of file hmac_drbg.c.

int mbedtls_hmac_drbg_seed_buf	(	mbedtls_hmac_drbg_context *	ctx,
		const mbedtls_md_info_t *	md_info,
		const unsigned char *	data,
		size_t	data_len
	)

Initilisation of simpified HMAC_DRBG (never reseeds).

(For use with deterministic ECDSA.)

Parameters:

ctx	HMAC_DRBG context to be initialised
md_info	MD algorithm to use for HMAC_DRBG
data	Concatenation of entropy string and additional data
data_len	Length of data in bytes

Returns:: 0 if successful, or MBEDTLS_ERR_MD_BAD_INPUT_DATA, or MBEDTLS_ERR_MD_ALLOC_FAILED.

Definition at line 101 of file hmac_drbg.c.

int mbedtls_hmac_drbg_self_test ( int verbose )

Checkup routine.

Returns:: 0 if successful, or 1 if the test failed

Definition at line 469 of file hmac_drbg.c.

void mbedtls_hmac_drbg_set_entropy_len	(	mbedtls_hmac_drbg_context *	ctx,
		size_t	len
	)

Set the amount of entropy grabbed on each reseed (Default: given by the security strength, which depends on the hash used, see mbedtls_hmac_drbg_init() )

Parameters:

ctx	HMAC_DRBG context
len	Amount of entropy to grab, in bytes

Definition at line 232 of file hmac_drbg.c.

void mbedtls_hmac_drbg_set_prediction_resistance	(	mbedtls_hmac_drbg_context *	ctx,
		int	resistance
	)

Enable / disable prediction resistance (Default: Off)

Note: If enabled, entropy is used for ctx->entropy_len before each call! Only use this if you have ample supply of good entropy!

Parameters:

ctx	HMAC_DRBG context
resistance	MBEDTLS_HMAC_DRBG_PR_ON or MBEDTLS_HMAC_DRBG_PR_OFF

Definition at line 223 of file hmac_drbg.c.

void mbedtls_hmac_drbg_set_reseed_interval	(	mbedtls_hmac_drbg_context *	ctx,
		int	interval
	)

Set the reseed interval (Default: MBEDTLS_HMAC_DRBG_RESEED_INTERVAL)

Parameters:

ctx	HMAC_DRBG context
interval	Reseed interval

Definition at line 240 of file hmac_drbg.c.

void mbedtls_hmac_drbg_update	(	mbedtls_hmac_drbg_context *	ctx,
		const unsigned char *	additional,
		size_t	add_len
	)

HMAC_DRBG update state.

Parameters:

ctx	HMAC_DRBG context
additional	Additional data to update state with, or NULL
add_len	Length of additional data, or 0

Note:: Additional data is optional, pass NULL and 0 as second third argument if no additional data is being used.

Definition at line 73 of file hmac_drbg.c.

int mbedtls_hmac_drbg_update_seed_file	(	mbedtls_hmac_drbg_context *	ctx,
		const char *	path
	)

Read and update a seed file.

Seed is added to this instance

Parameters:

ctx	HMAC_DRBG context
path	Name of the file

Returns:: 0 if successful, 1 on file error, MBEDTLS_ERR_HMAC_DRBG_ENTROPY_SOURCE_FAILED or MBEDTLS_ERR_HMAC_DRBG_INPUT_TOO_BIG

Definition at line 370 of file hmac_drbg.c.

int mbedtls_hmac_drbg_write_seed_file	(	mbedtls_hmac_drbg_context *	ctx,
		const char *	path
	)

Write a seed file.

Parameters:

ctx	HMAC_DRBG context
path	Name of the file

Returns:: 0 if successful, 1 on file error, or MBEDTLS_ERR_HMAC_DRBG_ENTROPY_SOURCE_FAILED

Definition at line 345 of file hmac_drbg.c.

Type:	Program
Mbed OS support:	Mbed OS
Created:	23 Feb 2019
Imports:	43
Forks:	0
Commits:	1
Dependents:	0
Dependencies:	0
Followers:	1

hmac_drbg.h File Reference

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hmac_drbg.h File Reference

Data Structures

Functions

Detailed Description

Function Documentation

Repository toolbox

Repository details

Important Information for this Arm website

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