diff --git a/include/mbedtls/ctr_drbg.h b/include/mbedtls/ctr_drbg.h index 2db402133..676b96e49 100644 --- a/include/mbedtls/ctr_drbg.h +++ b/include/mbedtls/ctr_drbg.h @@ -214,11 +214,8 @@ void mbedtls_ctr_drbg_init( mbedtls_ctr_drbg_context *ctx ); * with mbedtls_entropy_init() (which registers the platform's default * entropy sources). * - * \p f_entropy is always called with a buffer size equal to the entropy - * length. The entropy length is initially #MBEDTLS_CTR_DRBG_ENTROPY_LEN - * and this value is always used for the initial seeding. You can change - * the entropy length for subsequent seeding by calling - * mbedtls_ctr_drbg_set_entropy_len() after this function. + * The entropy length is #MBEDTLS_CTR_DRBG_ENTROPY_LEN by default. + * You can override it by calling mbedtls_ctr_drbg_set_entropy_len(). * * You can provide a personalization string in addition to the * entropy source, to make this instantiation as unique as possible. @@ -255,6 +252,8 @@ void mbedtls_ctr_drbg_init( mbedtls_ctr_drbg_context *ctx ); * \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 buffer size + * 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 @@ -298,7 +297,7 @@ void mbedtls_ctr_drbg_set_prediction_resistance( mbedtls_ctr_drbg_context *ctx, /** * \brief This function sets the amount of entropy grabbed on each - * subsequent reseed. + * seed or reseed. * * The default value is #MBEDTLS_CTR_DRBG_ENTROPY_LEN. * @@ -499,11 +498,6 @@ int mbedtls_ctr_drbg_self_test( int verbose ); #endif /* MBEDTLS_SELF_TEST */ -/* Internal functions (do not call directly) */ -int mbedtls_ctr_drbg_seed_entropy_len( mbedtls_ctr_drbg_context *, - int (*)(void *, unsigned char *, size_t), void *, - const unsigned char *, size_t, size_t ); - #ifdef __cplusplus } #endif diff --git a/library/ctr_drbg.c b/library/ctr_drbg.c index c986b7019..ae51d5467 100644 --- a/library/ctr_drbg.c +++ b/library/ctr_drbg.c @@ -381,10 +381,6 @@ exit: return( ret ); } -/* - * Non-public function wrapped by mbedtls_ctr_drbg_seed(). Necessary to allow - * NIST tests to succeed (which require known length fixed entropy) - */ /* CTR_DRBG_Instantiate with derivation function (SP 800-90A §10.2.1.3.2) * mbedtls_ctr_drbg_seed_entropy_len(ctx, f_entropy, p_entropy, * custom, len, entropy_len) @@ -397,13 +393,11 @@ exit: * and with outputs * ctx = initial_working_state */ -int mbedtls_ctr_drbg_seed_entropy_len( - mbedtls_ctr_drbg_context *ctx, - int (*f_entropy)(void *, unsigned char *, size_t), - void *p_entropy, - const unsigned char *custom, - size_t len, - size_t entropy_len ) +int mbedtls_ctr_drbg_seed( mbedtls_ctr_drbg_context *ctx, + int (*f_entropy)(void *, unsigned char *, size_t), + void *p_entropy, + const unsigned char *custom, + size_t len ) { int ret; unsigned char key[MBEDTLS_CTR_DRBG_KEYSIZE]; @@ -415,7 +409,8 @@ int mbedtls_ctr_drbg_seed_entropy_len( ctx->f_entropy = f_entropy; ctx->p_entropy = p_entropy; - ctx->entropy_len = entropy_len; + if( ctx->entropy_len == 0 ) + ctx->entropy_len = MBEDTLS_CTR_DRBG_ENTROPY_LEN; ctx->reseed_interval = MBEDTLS_CTR_DRBG_RESEED_INTERVAL; /* @@ -434,17 +429,6 @@ int mbedtls_ctr_drbg_seed_entropy_len( return( 0 ); } -int mbedtls_ctr_drbg_seed( mbedtls_ctr_drbg_context *ctx, - int (*f_entropy)(void *, unsigned char *, size_t), - void *p_entropy, - const unsigned char *custom, - size_t len ) -{ - return( mbedtls_ctr_drbg_seed_entropy_len( ctx, f_entropy, p_entropy, - custom, len, - MBEDTLS_CTR_DRBG_ENTROPY_LEN ) ); -} - /* CTR_DRBG_Generate with derivation function (SP 800-90A §10.2.1.5.2) * mbedtls_ctr_drbg_random_with_add(ctx, output, output_len, additional, add_len) * implements @@ -708,8 +692,11 @@ int mbedtls_ctr_drbg_self_test( int verbose ) mbedtls_printf( " CTR_DRBG (PR = TRUE) : " ); test_offset = 0; - CHK( mbedtls_ctr_drbg_seed_entropy_len( &ctx, ctr_drbg_self_test_entropy, - (void *) entropy_source_pr, nonce_pers_pr, 16, 32 ) ); + mbedtls_ctr_drbg_set_entropy_len( &ctx, 32 ); + CHK( mbedtls_ctr_drbg_seed( &ctx, + ctr_drbg_self_test_entropy, + (void *) entropy_source_pr, + nonce_pers_pr, 16 ) ); mbedtls_ctr_drbg_set_prediction_resistance( &ctx, MBEDTLS_CTR_DRBG_PR_ON ); CHK( mbedtls_ctr_drbg_random( &ctx, buf, MBEDTLS_CTR_DRBG_BLOCKSIZE ) ); CHK( mbedtls_ctr_drbg_random( &ctx, buf, MBEDTLS_CTR_DRBG_BLOCKSIZE ) ); @@ -729,8 +716,11 @@ int mbedtls_ctr_drbg_self_test( int verbose ) mbedtls_ctr_drbg_init( &ctx ); test_offset = 0; - CHK( mbedtls_ctr_drbg_seed_entropy_len( &ctx, ctr_drbg_self_test_entropy, - (void *) entropy_source_nopr, nonce_pers_nopr, 16, 32 ) ); + mbedtls_ctr_drbg_set_entropy_len( &ctx, 32 ); + CHK( mbedtls_ctr_drbg_seed( &ctx, + ctr_drbg_self_test_entropy, + (void *) entropy_source_nopr, + nonce_pers_nopr, 16 ) ); CHK( mbedtls_ctr_drbg_random( &ctx, buf, 16 ) ); CHK( mbedtls_ctr_drbg_reseed( &ctx, NULL, 0 ) ); CHK( mbedtls_ctr_drbg_random( &ctx, buf, 16 ) ); diff --git a/tests/suites/test_suite_ctr_drbg.function b/tests/suites/test_suite_ctr_drbg.function index 4a97826f6..01050d92d 100644 --- a/tests/suites/test_suite_ctr_drbg.function +++ b/tests/suites/test_suite_ctr_drbg.function @@ -44,11 +44,11 @@ static void ctr_drbg_validate_internal( int reseed_mode, data_t * nonce, /* CTR_DRBG_Instantiate(entropy[:entropy->len], nonce, perso, ) * where nonce||perso = nonce[nonce->len] */ - TEST_ASSERT( mbedtls_ctr_drbg_seed_entropy_len( + mbedtls_ctr_drbg_set_entropy_len( &ctx, entropy_chunk_len ); + TEST_ASSERT( mbedtls_ctr_drbg_seed( &ctx, mbedtls_test_entropy_func, entropy->x, - nonce->x, nonce->len, - entropy_chunk_len ) == 0 ); + nonce->x, nonce->len ) == 0 ); if( reseed_mode == RESEED_ALWAYS ) mbedtls_ctr_drbg_set_prediction_resistance( &ctx,