mbedtls/tests/suites/test_suite_random.function
Gilles Peskine 077599ad85 New test suite for random generation
Test random generation as a whole. This is different from
test_suite_*_drbg and test_suite_entropy, which respectively test PRNG
modules and entropy collection.

Start with basic tests: good-case tests, and do it twice and compare
the results to validate that entropy collection doesn't repeat itself.

Signed-off-by: Gilles Peskine <Gilles.Peskine@arm.com>
2021-02-03 18:55:39 +01:00

120 lines
4.0 KiB
Plaintext

/* BEGIN_HEADER */
/* Test random generation as a whole. */
#include "mbedtls/ctr_drbg.h"
#include "mbedtls/entropy.h"
#include "mbedtls/hmac_drbg.h"
#include "psa/crypto.h"
/* How many bytes to generate in each test case for repeated generation.
* This must be high enough that the probability of generating the same
* output twice is infinitesimal, but low enough that random generators
* are willing to deliver that much. */
#define OUTPUT_SIZE 32
/* END_HEADER */
/* BEGIN_CASE depends_on:MBEDTLS_ENTROPY_C:MBEDTLS_CTR_DRBG_C */
void random_twice_with_ctr_drbg( )
{
mbedtls_entropy_context entropy;
mbedtls_ctr_drbg_context drbg;
unsigned char output1[OUTPUT_SIZE];
unsigned char output2[OUTPUT_SIZE];
/* First round */
mbedtls_entropy_init( &entropy );
mbedtls_ctr_drbg_init( &drbg );
TEST_EQUAL( 0, mbedtls_ctr_drbg_seed( &drbg,
mbedtls_entropy_func, &entropy,
NULL, 0 ) );
TEST_EQUAL( 0, mbedtls_ctr_drbg_random( &drbg,
output1, sizeof( output1 ) ) );
mbedtls_ctr_drbg_free( &drbg );
mbedtls_entropy_free( &entropy );
/* Second round */
mbedtls_entropy_init( &entropy );
mbedtls_ctr_drbg_init( &drbg );
TEST_EQUAL( 0, mbedtls_ctr_drbg_seed( &drbg,
mbedtls_entropy_func, &entropy,
NULL, 0 ) );
TEST_EQUAL( 0, mbedtls_ctr_drbg_random( &drbg,
output2, sizeof( output2 ) ) );
mbedtls_ctr_drbg_free( &drbg );
mbedtls_entropy_free( &entropy );
/* The two rounds must generate different random data. */
TEST_ASSERT( memcmp( output1, output2, OUTPUT_SIZE ) != 0 );
exit:
mbedtls_ctr_drbg_free( &drbg );
mbedtls_entropy_free( &entropy );
}
/* END_CASE */
/* BEGIN_CASE depends_on:MBEDTLS_ENTROPY_C:MBEDTLS_HMAC_DRBG_C */
void random_twice_with_hmac_drbg( int md_type )
{
mbedtls_entropy_context entropy;
mbedtls_hmac_drbg_context drbg;
unsigned char output1[OUTPUT_SIZE];
unsigned char output2[OUTPUT_SIZE];
const mbedtls_md_info_t *md_info = mbedtls_md_info_from_type( md_type );
/* First round */
mbedtls_entropy_init( &entropy );
mbedtls_hmac_drbg_init( &drbg );
TEST_EQUAL( 0, mbedtls_hmac_drbg_seed( &drbg, md_info,
mbedtls_entropy_func, &entropy,
NULL, 0 ) );
TEST_EQUAL( 0, mbedtls_hmac_drbg_random( &drbg,
output1, sizeof( output1 ) ) );
mbedtls_hmac_drbg_free( &drbg );
mbedtls_entropy_free( &entropy );
/* Second round */
mbedtls_entropy_init( &entropy );
mbedtls_hmac_drbg_init( &drbg );
TEST_EQUAL( 0, mbedtls_hmac_drbg_seed( &drbg, md_info,
mbedtls_entropy_func, &entropy,
NULL, 0 ) );
TEST_EQUAL( 0, mbedtls_hmac_drbg_random( &drbg,
output2, sizeof( output2 ) ) );
mbedtls_hmac_drbg_free( &drbg );
mbedtls_entropy_free( &entropy );
/* The two rounds must generate different random data. */
TEST_ASSERT( memcmp( output1, output2, OUTPUT_SIZE ) != 0 );
exit:
mbedtls_hmac_drbg_free( &drbg );
mbedtls_entropy_free( &entropy );
}
/* END_CASE */
/* BEGIN_CASE depends_on:MBEDTLS_PSA_CRYPTO_C:!MBEDTLS_PSA_CRYPTO_EXTERNAL_RNG */
void random_twice_with_psa_from_psa( )
{
unsigned char output1[OUTPUT_SIZE];
unsigned char output2[OUTPUT_SIZE];
/* First round */
PSA_ASSERT( psa_crypto_init( ) );
PSA_ASSERT( psa_generate_random( output1, sizeof( output1 ) ) );
PSA_DONE( );
/* Second round */
PSA_ASSERT( psa_crypto_init( ) );
PSA_ASSERT( psa_generate_random( output2, sizeof( output2 ) ) );
PSA_DONE( );
/* The two rounds must generate different random data. */
TEST_ASSERT( memcmp( output1, output2, OUTPUT_SIZE ) != 0 );
exit:
PSA_DONE( );
}
/* END_CASE */