Fix entropy thresholds

This commit is contained in:
Manuel Pégourié-Gonnard 2015-06-19 09:40:51 +02:00
parent 60c793bdc9
commit bf82ff0209
3 changed files with 12 additions and 13 deletions

View File

@ -107,8 +107,8 @@ typedef struct
{
mbedtls_entropy_f_source_ptr f_source; /**< The entropy source callback */
void * p_source; /**< The callback data pointer */
size_t size; /**< Amount received */
size_t threshold; /**< Minimum level required before release */
size_t size; /**< Amount received in bytes */
size_t threshold; /**< Minimum bytes required before release */
}
mbedtls_entropy_source_state;
@ -155,7 +155,7 @@ void mbedtls_entropy_free( mbedtls_entropy_context *ctx );
* \param f_source Entropy function
* \param p_source Function data
* \param threshold Minimum required from source before entropy is released
* ( with mbedtls_entropy_func() )
* ( with mbedtls_entropy_func() ) (in bytes)
*
* \return 0 if successful or MBEDTLS_ERR_ENTROPY_MAX_SOURCES
*/

View File

@ -37,11 +37,11 @@ extern "C" {
#endif
/*
* Default thresholds for built-in sources
* Default thresholds for built-in sources, in bytes
*/
#define MBEDTLS_ENTROPY_MIN_PLATFORM 128 /**< Minimum for platform source */
#define MBEDTLS_ENTROPY_MIN_HAVEGE 128 /**< Minimum for HAVEGE */
#define MBEDTLS_ENTROPY_MIN_HARDCLOCK 32 /**< Minimum for mbedtls_timing_hardclock() */
#define MBEDTLS_ENTROPY_MIN_PLATFORM 32 /**< Minimum for platform source */
#define MBEDTLS_ENTROPY_MIN_HAVEGE 32 /**< Minimum for HAVEGE */
#define MBEDTLS_ENTROPY_MIN_HARDCLOCK 4 /**< Minimum for mbedtls_timing_hardclock() */
#if !defined(MBEDTLS_NO_PLATFORM_ENTROPY)
/**

View File

@ -250,7 +250,7 @@ int mbedtls_entropy_gather( mbedtls_entropy_context *ctx )
int mbedtls_entropy_func( void *data, unsigned char *output, size_t len )
{
int ret, count = 0, i, reached;
int ret, count = 0, i, done;
mbedtls_entropy_context *ctx = (mbedtls_entropy_context *) data;
unsigned char buf[MBEDTLS_ENTROPY_BLOCK_SIZE];
@ -276,13 +276,12 @@ int mbedtls_entropy_func( void *data, unsigned char *output, size_t len )
if( ( ret = entropy_gather_internal( ctx ) ) != 0 )
goto exit;
reached = 0;
done = 1;
for( i = 0; i < ctx->source_count; i++ )
if( ctx->source[i].size >= ctx->source[i].threshold )
reached++;
if( ctx->source[i].size < ctx->source[i].threshold )
done = 0;
}
while( reached != ctx->source_count );
while( ! done );
memset( buf, 0, MBEDTLS_ENTROPY_BLOCK_SIZE );