mirror of
https://github.com/yuzu-emu/mbedtls.git
synced 2025-02-02 17:21:09 +00:00
65fc0686a7
There were tests to ensure that each entropy source reaches its threshold, but no test that covers the total amount of entropy. Add test cases with a known set of entropy sources and make sure that we always gather at least MBEDTLS_ENTROPY_BLOCK_SIZE bytes from a strong source.
476 lines
15 KiB
Plaintext
476 lines
15 KiB
Plaintext
/* BEGIN_HEADER */
|
|
#include "mbedtls/entropy.h"
|
|
#include "mbedtls/entropy_poll.h"
|
|
#include "string.h"
|
|
|
|
typedef enum
|
|
{
|
|
DUMMY_CONSTANT_LENGTH, /* Output context->length bytes */
|
|
DUMMY_REQUESTED_LENGTH, /* Output whatever length was requested */
|
|
DUMMY_FAIL, /* Return an error code */
|
|
} entropy_dummy_instruction;
|
|
|
|
typedef struct
|
|
{
|
|
entropy_dummy_instruction instruction;
|
|
size_t length; /* Length to return for DUMMY_CONSTANT_LENGTH */
|
|
size_t calls; /* Incremented at each call */
|
|
} entropy_dummy_context;
|
|
|
|
/*
|
|
* Dummy entropy source
|
|
*
|
|
* If data is NULL, write exactly the requested length.
|
|
* Otherwise, write the length indicated by data or error if negative
|
|
*/
|
|
static int entropy_dummy_source( void *arg, unsigned char *output,
|
|
size_t len, size_t *olen )
|
|
{
|
|
entropy_dummy_context *context = arg;
|
|
++context->calls;
|
|
|
|
switch( context->instruction )
|
|
{
|
|
case DUMMY_CONSTANT_LENGTH:
|
|
*olen = context->length;
|
|
break;
|
|
case DUMMY_REQUESTED_LENGTH:
|
|
*olen = len;
|
|
break;
|
|
case DUMMY_FAIL:
|
|
return( MBEDTLS_ERR_ENTROPY_SOURCE_FAILED );
|
|
}
|
|
|
|
memset( output, 0x2a, *olen );
|
|
return( 0 );
|
|
}
|
|
|
|
/*
|
|
* Ability to clear entropy sources to allow testing with just predefined
|
|
* entropy sources. This function or tests depending on it might break if there
|
|
* are internal changes to how entropy sources are registered.
|
|
*
|
|
* To be called immediately after mbedtls_entropy_init().
|
|
*
|
|
* Just resetting the counter. New sources will overwrite existing ones.
|
|
* This might break memory checks in the future if sources need 'free-ing' then
|
|
* as well.
|
|
*/
|
|
static void entropy_clear_sources( mbedtls_entropy_context *ctx )
|
|
{
|
|
ctx->source_count = 0;
|
|
}
|
|
|
|
#if defined(MBEDTLS_ENTROPY_NV_SEED)
|
|
/*
|
|
* NV seed read/write functions that use a buffer instead of a file
|
|
*/
|
|
static unsigned char buffer_seed[MBEDTLS_ENTROPY_BLOCK_SIZE];
|
|
|
|
int buffer_nv_seed_read( unsigned char *buf, size_t buf_len )
|
|
{
|
|
if( buf_len != MBEDTLS_ENTROPY_BLOCK_SIZE )
|
|
return( -1 );
|
|
|
|
memcpy( buf, buffer_seed, MBEDTLS_ENTROPY_BLOCK_SIZE );
|
|
return( 0 );
|
|
}
|
|
|
|
int buffer_nv_seed_write( unsigned char *buf, size_t buf_len )
|
|
{
|
|
if( buf_len != MBEDTLS_ENTROPY_BLOCK_SIZE )
|
|
return( -1 );
|
|
|
|
memcpy( buffer_seed, buf, MBEDTLS_ENTROPY_BLOCK_SIZE );
|
|
return( 0 );
|
|
}
|
|
|
|
/*
|
|
* NV seed read/write helpers that fill the base seedfile
|
|
*/
|
|
static int write_nv_seed( unsigned char *buf, size_t buf_len )
|
|
{
|
|
FILE *f;
|
|
|
|
if( buf_len != MBEDTLS_ENTROPY_BLOCK_SIZE )
|
|
return( -1 );
|
|
|
|
if( ( f = fopen( MBEDTLS_PLATFORM_STD_NV_SEED_FILE, "w" ) ) == NULL )
|
|
return( -1 );
|
|
|
|
if( fwrite( buf, 1, MBEDTLS_ENTROPY_BLOCK_SIZE, f ) !=
|
|
MBEDTLS_ENTROPY_BLOCK_SIZE )
|
|
return( -1 );
|
|
|
|
fclose( f );
|
|
|
|
return( 0 );
|
|
}
|
|
|
|
int read_nv_seed( unsigned char *buf, size_t buf_len )
|
|
{
|
|
FILE *f;
|
|
|
|
if( buf_len != MBEDTLS_ENTROPY_BLOCK_SIZE )
|
|
return( -1 );
|
|
|
|
if( ( f = fopen( MBEDTLS_PLATFORM_STD_NV_SEED_FILE, "rb" ) ) == NULL )
|
|
return( -1 );
|
|
|
|
if( fread( buf, 1, MBEDTLS_ENTROPY_BLOCK_SIZE, f ) !=
|
|
MBEDTLS_ENTROPY_BLOCK_SIZE )
|
|
return( -1 );
|
|
|
|
fclose( f );
|
|
|
|
return( 0 );
|
|
}
|
|
#endif /* MBEDTLS_ENTROPY_NV_SEED */
|
|
/* END_HEADER */
|
|
|
|
/* BEGIN_DEPENDENCIES
|
|
* depends_on:MBEDTLS_ENTROPY_C
|
|
* END_DEPENDENCIES
|
|
*/
|
|
|
|
/* BEGIN_CASE depends_on:MBEDTLS_ENTROPY_NV_SEED:MBEDTLS_FS_IO */
|
|
void entropy_seed_file( char * path, int ret )
|
|
{
|
|
mbedtls_entropy_context ctx;
|
|
|
|
mbedtls_entropy_init( &ctx );
|
|
|
|
TEST_ASSERT( mbedtls_entropy_write_seed_file( &ctx, path ) == ret );
|
|
TEST_ASSERT( mbedtls_entropy_update_seed_file( &ctx, path ) == ret );
|
|
|
|
exit:
|
|
mbedtls_entropy_free( &ctx );
|
|
}
|
|
/* END_CASE */
|
|
|
|
/* BEGIN_CASE */
|
|
void entropy_no_sources( )
|
|
{
|
|
mbedtls_entropy_context ctx;
|
|
unsigned char buf[MBEDTLS_ENTROPY_BLOCK_SIZE];
|
|
|
|
mbedtls_entropy_init( &ctx );
|
|
entropy_clear_sources( &ctx );
|
|
TEST_EQUAL( mbedtls_entropy_func( &ctx, buf, sizeof( buf ) ),
|
|
MBEDTLS_ERR_ENTROPY_NO_SOURCES_DEFINED );
|
|
|
|
exit:
|
|
mbedtls_entropy_free( &ctx );
|
|
}
|
|
/* END_CASE */
|
|
|
|
/* BEGIN_CASE */
|
|
void entropy_too_many_sources( )
|
|
{
|
|
mbedtls_entropy_context ctx;
|
|
size_t i;
|
|
entropy_dummy_context dummy = {DUMMY_REQUESTED_LENGTH, 0, 0};
|
|
|
|
mbedtls_entropy_init( &ctx );
|
|
|
|
/*
|
|
* It's hard to tell precisely when the error will occur,
|
|
* since we don't know how many sources were automatically added.
|
|
*/
|
|
for( i = 0; i < MBEDTLS_ENTROPY_MAX_SOURCES; i++ )
|
|
(void) mbedtls_entropy_add_source( &ctx, entropy_dummy_source, &dummy,
|
|
16, MBEDTLS_ENTROPY_SOURCE_WEAK );
|
|
|
|
TEST_ASSERT( mbedtls_entropy_add_source( &ctx, entropy_dummy_source, &dummy,
|
|
16, MBEDTLS_ENTROPY_SOURCE_WEAK )
|
|
== MBEDTLS_ERR_ENTROPY_MAX_SOURCES );
|
|
|
|
exit:
|
|
mbedtls_entropy_free( &ctx );
|
|
}
|
|
/* END_CASE */
|
|
|
|
/* BEGIN_CASE depends_on:ENTROPY_HAVE_STRONG */
|
|
void entropy_func_len( int len, int ret )
|
|
{
|
|
mbedtls_entropy_context ctx;
|
|
unsigned char buf[MBEDTLS_ENTROPY_BLOCK_SIZE + 10] = { 0 };
|
|
unsigned char acc[MBEDTLS_ENTROPY_BLOCK_SIZE + 10] = { 0 };
|
|
size_t i, j;
|
|
|
|
mbedtls_entropy_init( &ctx );
|
|
|
|
/*
|
|
* See comments in mbedtls_entropy_self_test()
|
|
*/
|
|
for( i = 0; i < 8; i++ )
|
|
{
|
|
TEST_ASSERT( mbedtls_entropy_func( &ctx, buf, len ) == ret );
|
|
for( j = 0; j < sizeof( buf ); j++ )
|
|
acc[j] |= buf[j];
|
|
}
|
|
|
|
if( ret == 0 )
|
|
for( j = 0; j < (size_t) len; j++ )
|
|
TEST_ASSERT( acc[j] != 0 );
|
|
|
|
for( j = len; j < sizeof( buf ); j++ )
|
|
TEST_ASSERT( acc[j] == 0 );
|
|
}
|
|
/* END_CASE */
|
|
|
|
/* BEGIN_CASE */
|
|
void entropy_source_fail( char * path )
|
|
{
|
|
mbedtls_entropy_context ctx;
|
|
unsigned char buf[16];
|
|
entropy_dummy_context dummy = {DUMMY_FAIL, 0, 0};
|
|
|
|
mbedtls_entropy_init( &ctx );
|
|
|
|
TEST_ASSERT( mbedtls_entropy_add_source( &ctx, entropy_dummy_source,
|
|
&dummy, 16,
|
|
MBEDTLS_ENTROPY_SOURCE_WEAK )
|
|
== 0 );
|
|
|
|
TEST_ASSERT( mbedtls_entropy_func( &ctx, buf, sizeof( buf ) )
|
|
== MBEDTLS_ERR_ENTROPY_SOURCE_FAILED );
|
|
TEST_ASSERT( mbedtls_entropy_gather( &ctx )
|
|
== MBEDTLS_ERR_ENTROPY_SOURCE_FAILED );
|
|
#if defined(MBEDTLS_FS_IO) && defined(MBEDTLS_ENTROPY_NV_SEED)
|
|
TEST_ASSERT( mbedtls_entropy_write_seed_file( &ctx, path )
|
|
== MBEDTLS_ERR_ENTROPY_SOURCE_FAILED );
|
|
TEST_ASSERT( mbedtls_entropy_update_seed_file( &ctx, path )
|
|
== MBEDTLS_ERR_ENTROPY_SOURCE_FAILED );
|
|
#else
|
|
((void) path);
|
|
#endif
|
|
|
|
exit:
|
|
mbedtls_entropy_free( &ctx );
|
|
}
|
|
/* END_CASE */
|
|
|
|
/* BEGIN_CASE depends_on:ENTROPY_HAVE_STRONG */
|
|
void entropy_threshold( int threshold, int chunk_size, int result )
|
|
{
|
|
mbedtls_entropy_context ctx;
|
|
entropy_dummy_context dummy = {DUMMY_CONSTANT_LENGTH, chunk_size, 0};
|
|
unsigned char buf[MBEDTLS_ENTROPY_BLOCK_SIZE] = { 0 };
|
|
int ret;
|
|
|
|
mbedtls_entropy_init( &ctx );
|
|
|
|
TEST_ASSERT( mbedtls_entropy_add_source( &ctx, entropy_dummy_source,
|
|
&dummy, threshold,
|
|
MBEDTLS_ENTROPY_SOURCE_WEAK ) == 0 );
|
|
|
|
ret = mbedtls_entropy_func( &ctx, buf, sizeof( buf ) );
|
|
|
|
if( result >= 0 )
|
|
{
|
|
TEST_ASSERT( ret == 0 );
|
|
#if defined(MBEDTLS_ENTROPY_NV_SEED)
|
|
// Two times as much calls due to the NV seed update
|
|
result *= 2;
|
|
#endif
|
|
TEST_ASSERT( dummy.calls == (size_t) result );
|
|
}
|
|
else
|
|
{
|
|
TEST_ASSERT( ret == result );
|
|
}
|
|
|
|
exit:
|
|
mbedtls_entropy_free( &ctx );
|
|
}
|
|
/* END_CASE */
|
|
|
|
/* BEGIN_CASE */
|
|
void entropy_calls( int strength1, int strength2,
|
|
int threshold, int chunk_size,
|
|
int result )
|
|
{
|
|
/*
|
|
* if result >= 0: result = expected number of calls to source 1
|
|
* if result < 0: result = expected return code from mbedtls_entropy_func()
|
|
*/
|
|
|
|
mbedtls_entropy_context ctx;
|
|
entropy_dummy_context dummy1 = {DUMMY_CONSTANT_LENGTH, chunk_size, 0};
|
|
entropy_dummy_context dummy2 = {DUMMY_CONSTANT_LENGTH, chunk_size, 0};
|
|
unsigned char buf[MBEDTLS_ENTROPY_BLOCK_SIZE] = { 0 };
|
|
int ret;
|
|
|
|
mbedtls_entropy_init( &ctx );
|
|
entropy_clear_sources( &ctx );
|
|
|
|
TEST_ASSERT( mbedtls_entropy_add_source( &ctx, entropy_dummy_source,
|
|
&dummy1, threshold,
|
|
strength1 ) == 0 );
|
|
TEST_ASSERT( mbedtls_entropy_add_source( &ctx, entropy_dummy_source,
|
|
&dummy2, threshold,
|
|
strength2 ) == 0 );
|
|
|
|
ret = mbedtls_entropy_func( &ctx, buf, sizeof( buf ) );
|
|
|
|
if( result >= 0 )
|
|
{
|
|
TEST_ASSERT( ret == 0 );
|
|
TEST_ASSERT( dummy1.calls == (size_t) result );
|
|
}
|
|
else
|
|
{
|
|
TEST_ASSERT( ret == result );
|
|
}
|
|
|
|
exit:
|
|
mbedtls_entropy_free( &ctx );
|
|
}
|
|
/* END_CASE */
|
|
|
|
/* BEGIN_CASE depends_on:MBEDTLS_ENTROPY_NV_SEED:MBEDTLS_FS_IO */
|
|
void nv_seed_file_create( )
|
|
{
|
|
unsigned char buf[MBEDTLS_ENTROPY_BLOCK_SIZE];
|
|
|
|
memset( buf, 0, MBEDTLS_ENTROPY_BLOCK_SIZE );
|
|
|
|
TEST_ASSERT( write_nv_seed( buf, MBEDTLS_ENTROPY_BLOCK_SIZE ) == 0 );
|
|
}
|
|
/* END_CASE */
|
|
|
|
/* BEGIN_CASE depends_on:MBEDTLS_ENTROPY_NV_SEED:MBEDTLS_FS_IO:MBEDTLS_PLATFORM_NV_SEED_ALT */
|
|
void entropy_nv_seed_std_io( )
|
|
{
|
|
unsigned char io_seed[MBEDTLS_ENTROPY_BLOCK_SIZE];
|
|
unsigned char check_seed[MBEDTLS_ENTROPY_BLOCK_SIZE];
|
|
|
|
memset( io_seed, 1, MBEDTLS_ENTROPY_BLOCK_SIZE );
|
|
memset( check_seed, 0, MBEDTLS_ENTROPY_BLOCK_SIZE );
|
|
|
|
mbedtls_platform_set_nv_seed( mbedtls_platform_std_nv_seed_read,
|
|
mbedtls_platform_std_nv_seed_write );
|
|
|
|
/* Check if platform NV read and write manipulate the same data */
|
|
TEST_ASSERT( write_nv_seed( io_seed, MBEDTLS_ENTROPY_BLOCK_SIZE ) == 0 );
|
|
TEST_ASSERT( mbedtls_nv_seed_read( check_seed, MBEDTLS_ENTROPY_BLOCK_SIZE ) ==
|
|
MBEDTLS_ENTROPY_BLOCK_SIZE );
|
|
|
|
TEST_ASSERT( memcmp( io_seed, check_seed, MBEDTLS_ENTROPY_BLOCK_SIZE ) == 0 );
|
|
|
|
memset( check_seed, 0, MBEDTLS_ENTROPY_BLOCK_SIZE );
|
|
|
|
/* Check if platform NV write and raw read manipulate the same data */
|
|
TEST_ASSERT( mbedtls_nv_seed_write( io_seed, MBEDTLS_ENTROPY_BLOCK_SIZE ) ==
|
|
MBEDTLS_ENTROPY_BLOCK_SIZE );
|
|
TEST_ASSERT( read_nv_seed( check_seed, MBEDTLS_ENTROPY_BLOCK_SIZE ) == 0 );
|
|
|
|
TEST_ASSERT( memcmp( io_seed, check_seed, MBEDTLS_ENTROPY_BLOCK_SIZE ) == 0 );
|
|
}
|
|
/* END_CASE */
|
|
|
|
/* BEGIN_CASE depends_on:MBEDTLS_MD_C:MBEDTLS_ENTROPY_NV_SEED:MBEDTLS_PLATFORM_NV_SEED_ALT */
|
|
void entropy_nv_seed( data_t * read_seed )
|
|
{
|
|
#if defined(MBEDTLS_ENTROPY_SHA512_ACCUMULATOR)
|
|
const mbedtls_md_info_t *md_info =
|
|
mbedtls_md_info_from_type( MBEDTLS_MD_SHA512 );
|
|
#elif defined(MBEDTLS_ENTROPY_SHA256_ACCUMULATOR)
|
|
const mbedtls_md_info_t *md_info =
|
|
mbedtls_md_info_from_type( MBEDTLS_MD_SHA256 );
|
|
#else
|
|
#error "Unsupported entropy accumulator"
|
|
#endif
|
|
mbedtls_md_context_t accumulator;
|
|
mbedtls_entropy_context ctx;
|
|
int (*original_mbedtls_nv_seed_read)( unsigned char *buf, size_t buf_len ) =
|
|
mbedtls_nv_seed_read;
|
|
int (*original_mbedtls_nv_seed_write)( unsigned char *buf, size_t buf_len ) =
|
|
mbedtls_nv_seed_write;
|
|
|
|
unsigned char header[2];
|
|
unsigned char entropy[MBEDTLS_ENTROPY_BLOCK_SIZE];
|
|
unsigned char buf[MBEDTLS_ENTROPY_BLOCK_SIZE];
|
|
unsigned char empty[MBEDTLS_ENTROPY_BLOCK_SIZE];
|
|
unsigned char check_seed[MBEDTLS_ENTROPY_BLOCK_SIZE];
|
|
unsigned char check_entropy[MBEDTLS_ENTROPY_BLOCK_SIZE];
|
|
|
|
memset( entropy, 0, MBEDTLS_ENTROPY_BLOCK_SIZE );
|
|
memset( buf, 0, MBEDTLS_ENTROPY_BLOCK_SIZE );
|
|
memset( empty, 0, MBEDTLS_ENTROPY_BLOCK_SIZE );
|
|
memset( check_seed, 2, MBEDTLS_ENTROPY_BLOCK_SIZE );
|
|
memset( check_entropy, 3, MBEDTLS_ENTROPY_BLOCK_SIZE );
|
|
|
|
// Make sure we read/write NV seed from our buffers
|
|
mbedtls_platform_set_nv_seed( buffer_nv_seed_read, buffer_nv_seed_write );
|
|
|
|
mbedtls_md_init( &accumulator );
|
|
mbedtls_entropy_init( &ctx );
|
|
entropy_clear_sources( &ctx );
|
|
|
|
TEST_ASSERT( mbedtls_entropy_add_source( &ctx, mbedtls_nv_seed_poll, NULL,
|
|
MBEDTLS_ENTROPY_BLOCK_SIZE,
|
|
MBEDTLS_ENTROPY_SOURCE_STRONG ) == 0 );
|
|
|
|
// Set the initial NV seed to read
|
|
TEST_ASSERT( read_seed->len >= MBEDTLS_ENTROPY_BLOCK_SIZE );
|
|
memcpy( buffer_seed, read_seed->x, MBEDTLS_ENTROPY_BLOCK_SIZE );
|
|
|
|
// Do an entropy run
|
|
TEST_ASSERT( mbedtls_entropy_func( &ctx, entropy, sizeof( entropy ) ) == 0 );
|
|
// Determine what should have happened with manual entropy internal logic
|
|
|
|
// Init accumulator
|
|
header[1] = MBEDTLS_ENTROPY_BLOCK_SIZE;
|
|
TEST_ASSERT( mbedtls_md_setup( &accumulator, md_info, 0 ) == 0 );
|
|
|
|
// First run for updating write_seed
|
|
header[0] = 0;
|
|
TEST_ASSERT( mbedtls_md_starts( &accumulator ) == 0 );
|
|
TEST_ASSERT( mbedtls_md_update( &accumulator, header, 2 ) == 0 );
|
|
TEST_ASSERT( mbedtls_md_update( &accumulator,
|
|
read_seed->x, MBEDTLS_ENTROPY_BLOCK_SIZE ) == 0 );
|
|
TEST_ASSERT( mbedtls_md_finish( &accumulator, buf ) == 0 );
|
|
|
|
TEST_ASSERT( mbedtls_md_starts( &accumulator ) == 0 );
|
|
TEST_ASSERT( mbedtls_md_update( &accumulator,
|
|
buf, MBEDTLS_ENTROPY_BLOCK_SIZE ) == 0 );
|
|
|
|
TEST_ASSERT( mbedtls_md( md_info, buf, MBEDTLS_ENTROPY_BLOCK_SIZE,
|
|
check_seed ) == 0 );
|
|
|
|
// Second run for actual entropy (triggers mbedtls_entropy_update_nv_seed)
|
|
header[0] = MBEDTLS_ENTROPY_SOURCE_MANUAL;
|
|
TEST_ASSERT( mbedtls_md_update( &accumulator, header, 2 ) == 0 );
|
|
TEST_ASSERT( mbedtls_md_update( &accumulator,
|
|
empty, MBEDTLS_ENTROPY_BLOCK_SIZE ) == 0 );
|
|
|
|
header[0] = 0;
|
|
TEST_ASSERT( mbedtls_md_update( &accumulator, header, 2 ) == 0 );
|
|
TEST_ASSERT( mbedtls_md_update( &accumulator,
|
|
check_seed, MBEDTLS_ENTROPY_BLOCK_SIZE ) == 0 );
|
|
TEST_ASSERT( mbedtls_md_finish( &accumulator, buf ) == 0 );
|
|
|
|
TEST_ASSERT( mbedtls_md( md_info, buf, MBEDTLS_ENTROPY_BLOCK_SIZE,
|
|
check_entropy ) == 0 );
|
|
|
|
// Check result of both NV file and entropy received with the manual calculations
|
|
TEST_ASSERT( memcmp( check_seed, buffer_seed, MBEDTLS_ENTROPY_BLOCK_SIZE ) == 0 );
|
|
TEST_ASSERT( memcmp( check_entropy, entropy, MBEDTLS_ENTROPY_BLOCK_SIZE ) == 0 );
|
|
|
|
exit:
|
|
mbedtls_md_free( &accumulator );
|
|
mbedtls_entropy_free( &ctx );
|
|
mbedtls_nv_seed_read = original_mbedtls_nv_seed_read;
|
|
mbedtls_nv_seed_write = original_mbedtls_nv_seed_write;
|
|
}
|
|
/* END_CASE */
|
|
|
|
/* BEGIN_CASE depends_on:ENTROPY_HAVE_STRONG:MBEDTLS_SELF_TEST */
|
|
void entropy_selftest( int result )
|
|
{
|
|
TEST_ASSERT( mbedtls_entropy_self_test( 1 ) == result );
|
|
}
|
|
/* END_CASE */
|