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RT4116: Change cleanse to just memset

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See also the discussion in https://github.com/openssl/openssl/pull/455

Reviewed-by: Andy Polyakov <appro@openssl.org>
This commit is contained in:
Rich Salz 2016-02-25 08:29:52 -05:00 committed by Rich Salz
parent 380f18ed5f
commit 104ce8a9f0
1 changed files with 9 additions and 16 deletions
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25
crypto/mem_clr.c
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@ -59,23 +59,16 @@
#include <string.h>
#include <openssl/crypto.h>
extern unsigned char cleanse_ctr;
unsigned char cleanse_ctr = 0;
/*
* Pointer to memset is volatile so that compiler must de-reference
* the pointer and can't assume that it points to any function in
* particular (such as memset, which it then might further "optimize")
*/
typedef void *(*memset_t)(void *,int,size_t);
static volatile memset_t memset_func = memset;
void OPENSSL_cleanse(void *ptr, size_t len)
{
unsigned char *p = ptr;
size_t loop = len, ctr = cleanse_ctr;
if (ptr == NULL)
return;
while (loop--) {
*(p++) = (unsigned char)ctr;
ctr += (17 + ((size_t)p & 0xF));
}
p = memchr(ptr, (unsigned char)ctr, len);
if (p)
ctr += (63 + (size_t)p);
cleanse_ctr = (unsigned char)ctr;
memset_func(ptr, 0, len);
}