5fe94652cf
stack protection to allow execution for single-threaded processes.
178 lines
3.9 KiB
C
178 lines
3.9 KiB
C
/*-
|
|
* Copyright (c) 1998 John D. Polstra
|
|
* 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.
|
|
*/
|
|
|
|
#include <sys/cdefs.h>
|
|
__FBSDID("$FreeBSD$");
|
|
|
|
/*
|
|
* Linkage to services provided by the dynamic linker.
|
|
*/
|
|
#include <sys/mman.h>
|
|
#include <dlfcn.h>
|
|
#include <link.h>
|
|
#include <stddef.h>
|
|
|
|
static char sorry[] = "Service unavailable";
|
|
|
|
/*
|
|
* For ELF, the dynamic linker directly resolves references to its
|
|
* services to functions inside the dynamic linker itself. These
|
|
* weak-symbol stubs are necessary so that "ld" won't complain about
|
|
* undefined symbols. The stubs are executed only when the program is
|
|
* linked statically, or when a given service isn't implemented in the
|
|
* dynamic linker. They must return an error if called, and they must
|
|
* be weak symbols so that the dynamic linker can override them.
|
|
*/
|
|
|
|
#pragma weak _rtld_error
|
|
void
|
|
_rtld_error(const char *fmt, ...)
|
|
{
|
|
}
|
|
|
|
#pragma weak dladdr
|
|
int
|
|
dladdr(const void *addr, Dl_info *dlip)
|
|
{
|
|
_rtld_error(sorry);
|
|
return 0;
|
|
}
|
|
|
|
#pragma weak dlclose
|
|
int
|
|
dlclose(void *handle)
|
|
{
|
|
_rtld_error(sorry);
|
|
return -1;
|
|
}
|
|
|
|
#pragma weak dlerror
|
|
char *
|
|
dlerror(void)
|
|
{
|
|
return sorry;
|
|
}
|
|
|
|
#pragma weak dllockinit
|
|
void
|
|
dllockinit(void *context,
|
|
void *(*lock_create)(void *context),
|
|
void (*rlock_acquire)(void *lock),
|
|
void (*wlock_acquire)(void *lock),
|
|
void (*lock_release)(void *lock),
|
|
void (*lock_destroy)(void *lock),
|
|
void (*context_destroy)(void *context))
|
|
{
|
|
if (context_destroy != NULL)
|
|
context_destroy(context);
|
|
}
|
|
|
|
#pragma weak dlopen
|
|
void *
|
|
dlopen(const char *name, int mode)
|
|
{
|
|
_rtld_error(sorry);
|
|
return NULL;
|
|
}
|
|
|
|
#pragma weak dlsym
|
|
void *
|
|
dlsym(void * __restrict handle, const char * __restrict name)
|
|
{
|
|
_rtld_error(sorry);
|
|
return NULL;
|
|
}
|
|
|
|
#pragma weak dlfunc
|
|
dlfunc_t
|
|
dlfunc(void * __restrict handle, const char * __restrict name)
|
|
{
|
|
_rtld_error(sorry);
|
|
return NULL;
|
|
}
|
|
|
|
#pragma weak dlvsym
|
|
void *
|
|
dlvsym(void * __restrict handle, const char * __restrict name,
|
|
const char * __restrict version)
|
|
{
|
|
_rtld_error(sorry);
|
|
return NULL;
|
|
}
|
|
|
|
#pragma weak dlinfo
|
|
int
|
|
dlinfo(void * __restrict handle, int request, void * __restrict p)
|
|
{
|
|
_rtld_error(sorry);
|
|
return 0;
|
|
}
|
|
|
|
#pragma weak _rtld_thread_init
|
|
void
|
|
_rtld_thread_init(void * li)
|
|
{
|
|
_rtld_error(sorry);
|
|
}
|
|
|
|
#pragma weak dl_iterate_phdr
|
|
int
|
|
dl_iterate_phdr(int (*callback)(struct dl_phdr_info *, size_t, void *),
|
|
void *data)
|
|
{
|
|
_rtld_error(sorry);
|
|
return 0;
|
|
}
|
|
|
|
#pragma weak _rtld_atfork_pre
|
|
void
|
|
_rtld_atfork_pre(int *locks)
|
|
{
|
|
}
|
|
|
|
#pragma weak _rtld_atfork_post
|
|
void
|
|
_rtld_atfork_post(int *locks)
|
|
{
|
|
}
|
|
|
|
#pragma weak _rtld_addr_phdr
|
|
int
|
|
_rtld_addr_phdr(const void *addr, struct dl_phdr_info *phdr_info)
|
|
{
|
|
|
|
return (0);
|
|
}
|
|
|
|
#pragma weak _rtld_get_stack_prot
|
|
int
|
|
_rtld_get_stack_prot(void)
|
|
{
|
|
|
|
return (PROT_EXEC | PROT_READ | PROT_WRITE);
|
|
}
|
|
|