SwitchEmu/mbedtls
1
0
Fork 0
mirror of https://git.suyu.dev/suyu/mbedtls.git synced 2026-03-03 19:46:42 +00:00
Code Issues Packages Projects Releases Wiki Activity

- Removed dependency of tests on rand()

Browse Source 
- Added pseudo-random helper function
This commit is contained in:
Paul Bakker
2011-03-13 15:45:42 +00:00
parent 9dcc32236b
commit 997bbd10d8
4 changed files with 65 additions and 25 deletions
Download Patch File Download Diff File Expand all files Collapse all files

58
tests/suites/helpers.function
View File

@@ -58,6 +58,10 @@ void hexify(unsigned char *obuf, const unsigned char *ibuf, int len)
/**
* This function just returns data from rand().
* Although predictable and often similar on multiple
* runs, this does not result in identical random on
* each run. So do not use this if the results of a
* test depend on the random data that is generated.
*
* rng_state shall be NULL.
*/
@@ -87,23 +91,32 @@ typedef struct
unsigned char *buf;
int length;
int per_call;
} rnd_info;
} rnd_buf_info;
/**
* This function returns random based on a buffer it receives.
*
* rng_state shall be a pointer to a rnd_buf structure.
* rng_state shall be a pointer to a rnd_buf_info structure.
*
* The number of bytes released from the buffer on each call to
* the random function is specified by per_call. (Can be between
* 1 and 4)
*
* After the buffer is empty it will return rand();
*/
static int rnd_buffer_rand( void *rng_state )
{
rnd_info *info = (rnd_info *) rng_state;
rnd_buf_info *info = (rnd_buf_info *) rng_state;
int res;
if( rng_state == NULL )
return( rand() );
if( info->per_call > 4 )
info->per_call = 4;
else if( info->per_call < 1 )
info->per_call = 1;
res = rand();
if( info->length >= info->per_call )
@@ -120,3 +133,42 @@ static int rnd_buffer_rand( void *rng_state )
return( res );
}
/**
* Info structure for the pseudo random function
*
* Key should be set at the start to a test-unique value.
* State( v0, v1 ) should be set to zero.
*/
typedef struct
{
unsigned char key[16];
uint32_t v0, v1;
} rnd_pseudo_info;
/**
* This function returns random based on a pseudo random function.
* This means the results should be identical on all systems.
* Pseudo random is based on the XTEA encryption algorithm to
* generate pseudorandom.
*
* rng_state shall be a pointer to a rnd_pseudo_info structure.
*/
static int rnd_pseudo_rand( void *rng_state )
{
rnd_pseudo_info *info = (rnd_pseudo_info *) rng_state;
uint32_t i, *k, sum, delta=0x9E3779B9;
if( rng_state == NULL )
return( rand() );
k = (uint32_t *) info->key;
for( i = 0; i < 32; i++ )
{
info->v0 += (((info->v1 << 4) ^ (info->v1 >> 5)) + info->v1) ^ (sum + k[sum & 3]);
sum += delta;
info->v1 += (((info->v0 << 4) ^ (info->v0 >> 5)) + info->v0) ^ (sum + k[(sum>>11) & 3]);
}
return( info->v0 );
}