glibc/sysdeps/generic/dl-osinfo.h

60 lines
1.8 KiB
C

/* Operating system specific code for generic dynamic loader functions.
Copyright (C) 2009-2014 Free Software Foundation, Inc.
This file is part of the GNU C Library.
The GNU C Library is free software; you can redistribute it and/or
modify it under the terms of the GNU Lesser General Public
License as published by the Free Software Foundation; either
version 2.1 of the License, or (at your option) any later version.
The GNU C Library is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
Lesser General Public License for more details.
You should have received a copy of the GNU Lesser General Public
License along with the GNU C Library; if not, see
<http://www.gnu.org/licenses/>. */
#include <endian.h>
#include <stdint.h>
static inline uintptr_t __attribute__ ((always_inline))
_dl_setup_stack_chk_guard (void *dl_random)
{
union
{
uintptr_t num;
unsigned char bytes[sizeof (uintptr_t)];
} ret = { 0 };
if (dl_random == NULL)
{
ret.bytes[sizeof (ret) - 1] = 255;
ret.bytes[sizeof (ret) - 2] = '\n';
}
else
{
memcpy (ret.bytes, dl_random, sizeof (ret));
#if BYTE_ORDER == LITTLE_ENDIAN
ret.num &= ~(uintptr_t) 0xff;
#elif BYTE_ORDER == BIG_ENDIAN
ret.num &= ~((uintptr_t) 0xff << (8 * (sizeof (ret) - 1)));
#else
# error "BYTE_ORDER unknown"
#endif
}
return ret.num;
}
static inline uintptr_t __attribute__ ((always_inline))
_dl_setup_pointer_guard (void *dl_random, uintptr_t stack_chk_guard)
{
uintptr_t ret;
if (dl_random == NULL)
ret = stack_chk_guard;
else
memcpy (&ret, (char *) dl_random + sizeof (ret), sizeof (ret));
return ret;
}