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Improve seed() function

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Landon Curt Noll
2021-12-07 00:44:57 -08:00
parent f9464652fe
commit 7ffbaf922e
7 changed files with 190 additions and 24 deletions
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30
seed.c
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@@ -80,7 +80,7 @@
#endif
#if defined(HAVE_STDLIB_H)
# include <stdlib.h>
# define RANDOM_CNT (32) /* double random() call repeat count */
# define RANDOM_CNT (64) /* double random() call repeat count */
# define INITSTATE_SIZE (256) /* initstate pool size */
#endif
#include <setjmp.h>
@@ -96,6 +96,7 @@
#include "have_rusage.h"
#include "have_uid_t.h"
#include "have_environ.h"
#include "have_arc4random.h"
#if defined(HAVE_USTAT)
# include <ustat.h>
#endif
@@ -127,6 +128,11 @@ static hash64 prev_hash64 = { 0, 0 }; /* previous pseudo_seed() return or 0 */
extern char **environ; /* user environment */
#endif /* HAVE_ENVIRON */
#if defined(HAVE_ARC4RANDOM)
#define ARC4_BUFLEN (256)
static char arc4_buf[ARC4_BUFLEN];
#endif /* HAVE_ARC4RANDOM */
/*
* call counter - number of times pseudo_seed() as been called
@@ -562,10 +568,11 @@ pseudo_seed(void)
pash_hash = (unsigned)(prev_hash64.w32[0] ^ prev_hash64.w32[1]);
#endif /* HAVE_B64 */
/* classic random seeded with time of day, count, prev hash */
/* classic 31-bit random seeded with time of day, count, prev hash */
srandom((unsigned)(sdata.time) ^ (unsigned)call_count ^ past_hash);
for (j=0; j < RANDOM_CNT; ++j) {
for (j=0; j < RANDOM_CNT; j += 2) {
random_before[j] = random();
random_before[j+1] = (random() << 1);
}
/* initialize random state with the FNV hash of sdata */
@@ -579,9 +586,10 @@ pseudo_seed(void)
INITSTATE_SIZE);
#endif /* HAVE_B64 */
/* use random again with the new random state */
for (j=0; j < RANDOM_CNT; ++j) {
random_after[j] = random() ^ (random() << 1);
/* use 31-bit random some more with the new random state */
for (j=0; j < RANDOM_CNT; j += 2) {
random_after[j] = random();
random_after[j+1] = (random() << 1);
}
/*
@@ -604,6 +612,16 @@ pseudo_seed(void)
sizeof(random_after));
#endif /* HAVE_STDLIB_H */
#if defined(HAVE_ARC4RANDOM)
/*
* hash from a cryptographic pseudo-random number generator
*/
arc4random_buf(arc4_buf, ARC4_BUFLEN);
hash_val = private_hash64_buf(hash_val,
(char *)arc4_buf,
ARC4_BUFLEN);
#endif /* HAVE_ARC4RANDOM */
/*
* load the hash data into the ZVALUE
*