More entropy functions made thread-safe (add_source, update_manual, gather)

This commit is contained in:
Paul Bakker 2014-02-06 15:01:20 +01:00
parent 9eae7aae80
commit 47703a0a80
3 changed files with 63 additions and 7 deletions

View file

@ -13,6 +13,8 @@ Features
Changes
* Deprecated the Memory layer
* entropy_add_source(), entropy_update_manual() and entropy_gather()
now thread-safe if POLARSSL_THREADING_C defined
Bugfix
* ecp_gen_keypair() does more tries to prevent failure because of

View file

@ -133,6 +133,7 @@ void entropy_free( entropy_context *ctx );
/**
* \brief Adds an entropy source to poll
* (Thread-safe if POLARSSL_THREADING_C is enabled)
*
* \param ctx Entropy context
* \param f_source Entropy function
@ -148,6 +149,7 @@ int entropy_add_source( entropy_context *ctx,
/**
* \brief Trigger an extra gather poll for the accumulator
* (Thread-safe if POLARSSL_THREADING_C is enabled)
*
* \param ctx Entropy context
*
@ -169,6 +171,7 @@ int entropy_func( void *data, unsigned char *output, size_t len );
/**
* \brief Add data to the accumulator manually
* (Thread-safe if POLARSSL_THREADING_C is enabled)
*
* \param ctx Entropy context
* \param data Data to add

View file

@ -80,10 +80,19 @@ int entropy_add_source( entropy_context *ctx,
f_source_ptr f_source, void *p_source,
size_t threshold )
{
int index = ctx->source_count;
int index, ret = 0;
#if defined(POLARSSL_THREADING_C)
if( ( ret = polarssl_mutex_lock( &ctx->mutex ) ) != 0 )
return( ret );
#endif
index = ctx->source_count;
if( index >= ENTROPY_MAX_SOURCES )
return( POLARSSL_ERR_ENTROPY_MAX_SOURCES );
{
ret = POLARSSL_ERR_ENTROPY_MAX_SOURCES;
goto exit;
}
ctx->source[index].f_source = f_source;
ctx->source[index].p_source = p_source;
@ -91,7 +100,13 @@ int entropy_add_source( entropy_context *ctx,
ctx->source_count++;
return( 0 );
exit:
#if defined(POLARSSL_THREADING_C)
if( polarssl_mutex_unlock( &ctx->mutex ) != 0 )
return( POLARSSL_ERR_THREADING_MUTEX_ERROR );
#endif
return( ret );
}
/*
@ -133,18 +148,32 @@ static int entropy_update( entropy_context *ctx, unsigned char source_id,
int entropy_update_manual( entropy_context *ctx,
const unsigned char *data, size_t len )
{
return entropy_update( ctx, ENTROPY_SOURCE_MANUAL, data, len );
int ret;
#if defined(POLARSSL_THREADING_C)
if( ( ret = polarssl_mutex_lock( &ctx->mutex ) ) != 0 )
return( ret );
#endif
ret = entropy_update( ctx, ENTROPY_SOURCE_MANUAL, data, len );
#if defined(POLARSSL_THREADING_C)
if( polarssl_mutex_unlock( &ctx->mutex ) != 0 )
return( POLARSSL_ERR_THREADING_MUTEX_ERROR );
#endif
return ( ret );
}
/*
* Run through the different sources to add entropy to our accumulator
*/
int entropy_gather( entropy_context *ctx )
static int entropy_gather_internal( entropy_context *ctx )
{
int ret, i;
unsigned char buf[ENTROPY_MAX_GATHER];
size_t olen;
if( ctx->source_count == 0 )
return( POLARSSL_ERR_ENTROPY_NO_SOURCES_DEFINED );
@ -173,6 +202,28 @@ int entropy_gather( entropy_context *ctx )
return( 0 );
}
/*
* Thread-safe wrapper for entropy_gather_internal()
*/
int entropy_gather( entropy_context *ctx )
{
int ret;
#if defined(POLARSSL_THREADING_C)
if( ( ret = polarssl_mutex_lock( &ctx->mutex ) ) != 0 )
return( ret );
#endif
ret = entropy_gather_internal( ctx );
#if defined(POLARSSL_THREADING_C)
if( polarssl_mutex_unlock( &ctx->mutex ) != 0 )
return( POLARSSL_ERR_THREADING_MUTEX_ERROR );
#endif
return ( ret );
}
int entropy_func( void *data, unsigned char *output, size_t len )
{
int ret, count = 0, i, reached;
@ -198,7 +249,7 @@ int entropy_func( void *data, unsigned char *output, size_t len )
goto exit;
}
if( ( ret = entropy_gather( ctx ) ) != 0 )
if( ( ret = entropy_gather_internal( ctx ) ) != 0 )
goto exit;
reached = 0;