mirror of
https://github.com/hashcat/hashcat.git
synced 2025-07-04 05:42:35 +00:00
70 lines
2.9 KiB
C
70 lines
2.9 KiB
C
/*-
|
|
* Copyright 2014 Colin Percival
|
|
* All rights reserved.
|
|
*
|
|
* Redistribution and use in source and binary forms, with or without
|
|
* modification, are permitted provided that the following conditions
|
|
* are met:
|
|
* 1. Redistributions of source code must retain the above copyright
|
|
* notice, this list of conditions and the following disclaimer.
|
|
* 2. Redistributions in binary form must reproduce the above copyright
|
|
* notice, this list of conditions and the following disclaimer in the
|
|
* documentation and/or other materials provided with the distribution.
|
|
*
|
|
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
|
|
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
|
|
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
|
|
* ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
|
|
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
|
|
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
|
|
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
|
|
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
|
|
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
|
|
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
|
|
* SUCH DAMAGE.
|
|
*/
|
|
|
|
#ifndef _INSECURE_MEMZERO_H_
|
|
#define _INSECURE_MEMZERO_H_
|
|
|
|
#ifdef SKIP_MEMZERO
|
|
#define insecure_memzero(buf, len) /* empty */
|
|
#else
|
|
|
|
#include <stddef.h>
|
|
|
|
/* Pointer to memory-zeroing function. */
|
|
extern void (* volatile insecure_memzero_ptr)(volatile void *, size_t);
|
|
|
|
/**
|
|
* insecure_memzero(buf, len):
|
|
* Attempt to zero ${len} bytes at ${buf} in spite of optimizing compilers'
|
|
* best (standards-compliant) attempts to remove the buffer-zeroing. In
|
|
* particular, to avoid performing the zeroing, a compiler would need to
|
|
* use optimistic devirtualization; recognize that non-volatile objects do not
|
|
* need to be treated as volatile, even if they are accessed via volatile
|
|
* qualified pointers; and perform link-time optimization; in addition to the
|
|
* dead-code elimination which often causes buffer-zeroing to be elided.
|
|
*
|
|
* Note however that zeroing a buffer does not guarantee that the data held
|
|
* in the buffer is not stored elsewhere; in particular, there may be copies
|
|
* held in CPU registers or in anonymous allocations on the stack, even if
|
|
* every named variable is successfully sanitized. Solving the "wipe data
|
|
* from the system" problem will require a C language extension which does not
|
|
* yet exist.
|
|
*
|
|
* For more information, see:
|
|
* http://www.daemonology.net/blog/2014-09-04-how-to-zero-a-buffer.html
|
|
* http://www.daemonology.net/blog/2014-09-06-zeroing-buffers-is-insufficient.html
|
|
*/
|
|
static inline void
|
|
insecure_memzero(volatile void * buf, size_t len)
|
|
{
|
|
|
|
(insecure_memzero_ptr)(buf, len);
|
|
}
|
|
|
|
#endif
|
|
|
|
#endif /* !_INSECURE_MEMZERO_H_ */
|