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Refine trng_get_bytes for consistency and readability

pull/5634/head
cyliangtw 2017-11-13 12:11:08 +08:00 committed by adbridge
parent 393dff7233
commit 7b3d68e12f
2 changed files with 24 additions and 16 deletions
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20
targets/TARGET_NUVOTON/TARGET_M480/trng_api.c
View File

@ -25,6 +25,9 @@
/* /*
* Get Random number generator. * Get Random number generator.
*/ */
#define PRNG_KEY_SIZE (0x20UL)
static volatile int g_PRNG_done; static volatile int g_PRNG_done;
volatile int g_AES_done; volatile int g_AES_done;
@ -82,18 +85,19 @@ void trng_free(trng_t *obj)
int trng_get_bytes(trng_t *obj, uint8_t *output, size_t length, size_t *output_length) int trng_get_bytes(trng_t *obj, uint8_t *output, size_t length, size_t *output_length)
{ {
(void)obj; (void)obj;
unsigned char tmpBuff[32]; unsigned char tmpBuff[PRNG_KEY_SIZE];
size_t cur_length = 0; size_t cur_length = 0;
for (unsigned i = 0; i < (length/32); i++) { while (length >= sizeof(tmpBuff)) {
trng_get(output); trng_get(output);
cur_length += 32; output += sizeof(tmpBuff);
output += 32; cur_length += sizeof(tmpBuff);
} length -= sizeof(tmpBuff);
if( length > cur_length ) { }
if (length > 0) {
trng_get(tmpBuff); trng_get(tmpBuff);
memcpy(output, &tmpBuff, (length - cur_length)); memcpy(output, tmpBuff, length);
cur_length = length; cur_length += length;
trng_zeroize(tmpBuff, sizeof(tmpBuff)); trng_zeroize(tmpBuff, sizeof(tmpBuff));
} }
*output_length = cur_length; *output_length = cur_length;

20
targets/TARGET_NUVOTON/TARGET_NUC472/trng_api.c
View File

@ -30,6 +30,9 @@
/* /*
* Get Random number generator. * Get Random number generator.
*/ */
#define PRNG_KEY_SIZE (0x20UL)
static volatile int g_PRNG_done; static volatile int g_PRNG_done;
volatile int g_AES_done; volatile int g_AES_done;
@ -87,18 +90,19 @@ void trng_free(trng_t *obj)
int trng_get_bytes(trng_t *obj, uint8_t *output, size_t length, size_t *output_length) int trng_get_bytes(trng_t *obj, uint8_t *output, size_t length, size_t *output_length)
{ {
(void)obj; (void)obj;
unsigned char tmpBuff[32]; unsigned char tmpBuff[PRNG_KEY_SIZE];
size_t cur_length = 0; size_t cur_length = 0;
for (unsigned i = 0; i < (length/32); i++) { while (length >= sizeof(tmpBuff)) {
trng_get(output); trng_get(output);
cur_length += 32; output += sizeof(tmpBuff);
output += 32; cur_length += sizeof(tmpBuff);
} length -= sizeof(tmpBuff);
if( length > cur_length ) { }
if (length > 0) {
trng_get(tmpBuff); trng_get(tmpBuff);
memcpy(output, &tmpBuff, (length - cur_length)); memcpy(output, tmpBuff, length);
cur_length = length; cur_length += length;
trng_zeroize(tmpBuff, sizeof(tmpBuff)); trng_zeroize(tmpBuff, sizeof(tmpBuff));
} }
*output_length = cur_length; *output_length = cur_length;