byte_zzero(3)
limb manual
byte_zzero(3)
NAME
byte_zzero - fill a byte array with zeroes
SYNOPSIS
#include <limb/bytestr.h>
void byte_zzero(const char *arr, size_t len)
DESCRIPTION
The byte_zzero() function writes zeroes in the len bytes of memory pointed
by arr.
It guarantees that compiler optimizations will not remove the erase operation if the compiler deduces that the operation is "unnecessary" (e.g. memory is not used afterwards), which may be of importance when erasing sensitive information, such as keys in a cryptographic context.
Note
In order to ensure memory is erased :
- if available, explicit_bzero(3) is called,
- otherwise, Otherwise, memset(3) is used to clear the memory, then a special no-op function with a weak alias is called, in order to trick the compiler.