lib/mbedtls
1
0
Fork 0
mirror of https://github.com/Mbed-TLS/mbedtls.git synced 2025-07-29 11:41:15 +03:00
Code Activity

Add entropy callbacks to HMAC_DRBG

Browse Source
This commit is contained in:
Manuel Pégourié-Gonnard
2014-01-30 15:06:40 +01:00
parent 8208d167da
commit fe34a5fb83
3 changed files with 135 additions and 13 deletions
Download Patch File Download Diff File Expand all files Collapse all files

66
include/polarssl/hmac_drbg.h
View File

@ -29,19 +29,40 @@
#include "md.h"
/*
* ! Same values as ctr_drbg.h !
*/
#define POLARSSL_ERR_HMAC_DRBG_ENTROPY_SOURCE_FAILED -0x0034 /**< The entropy source failed. */
#define POLARSSL_ERR_HMAC_DRBG_REQUEST_TOO_BIG -0x0036 /**< Too many random requested in single call. */
#define POLARSSL_ERR_HMAC_DRBG_INPUT_TOO_BIG -0x0038 /**< Input too large (Entropy + additional). */
#define POLARSSL_ERR_HMAC_DRBG_FILE_IO_ERROR -0x003A /**< Read/write error in file. */
#define HMAC_DRBG_RESEED_INTERVAL 10000 /**< Interval before reseed is performed by default */
#define HMAC_DRBG_MAX_INPUT 256 /**< Maximum number of additional input bytes */
#define HMAC_DRBG_MAX_REQUEST 1024 /**< Maximum number of requested bytes per call */
#define HMAC_DRBG_MAX_SEED_INPUT 384 /**< Maximum size of (re)seed buffer */
#ifdef __cplusplus
extern "C" {
#endif
/*
* Simplified HMAC_DRBG context.
* No reseed counter, no prediction resistance flag.
/**
* HMAC_DRBG context.
* TODO: reseed counter, prediction resistance flag.
*/
typedef struct
{
md_context_t md_ctx;
unsigned char V[POLARSSL_MD_MAX_SIZE];
unsigned char K[POLARSSL_MD_MAX_SIZE];
size_t entropy_len; /*!< entropy bytes grabbed on each (re)seed */
/*
* Callbacks (Entropy)
*/
int (*f_entropy)(void *, unsigned char *, size_t);
void *p_entropy; /*!< context for the entropy function */
} hmac_drbg_context;
/**
@ -49,18 +70,47 @@ typedef struct
*
* \param ctx HMAC_DRBG context to be initialised
* \param md_info MD algorithm to use for HMAC_DRBG
* \param data Concatenation of entropy string and additional data
* \param data_len Length of data in bytes
* \param f_entropy Entropy callback (p_entropy, buffer to fill, buffer
* length)
* \param p_entropy Entropy context
* \param custom Personalization data (Device specific identifiers)
* (Can be NULL)
* \param len Length of personalization data
*
* \todo Use entropy callback rather than buffer.
* \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.
*
* \return 0 if successful, or
* POLARSSL_ERR_MD_BAD_INPUT_DATA, or
* POLARSSL_ERR_MD_ALLOC_FAILED
* POLARSSL_ERR_MD_ALLOC_FAILED, or
* POLARSSL_ERR_CTR_DRBG_ENTROPY_SOURCE_FAILED.
*/
int hmac_drbg_init( hmac_drbg_context *ctx,
const md_info_t * md_info,
const unsigned char *data, size_t data_len );
int (*f_entropy)(void *, unsigned char *, size_t),
void *p_entropy,
const unsigned char *custom,
size_t len );
/**
* \brief Simplified HMAC_DRBG initialisation.
* (For use with deterministic ECDSA.)
*
* \param ctx HMAC_DRBG context to be initialised
* \param md_info MD algorithm to use for HMAC_DRBG
* \param data Concatenation of entropy string and additional data
* \param data_len Length of data in bytes
*
* \return 0 if successful, or
* POLARSSL_ERR_MD_BAD_INPUT_DATA, or
* POLARSSL_ERR_MD_ALLOC_FAILED.
*/
int hmac_drbg_init_buf( hmac_drbg_context *ctx,
const md_info_t * md_info,
const unsigned char *data, size_t data_len );
/**
* \brief HMAC_DRBG update state