freebsd-skq/tools/test/vm86/vm86_test.c
Konstantin Belousov b3092f3cf0 Add a test for vm86(2), simple to use and diagnose.
MFC after:	1 week
Sponsored by:	The FreeBSD Foundation
2018-05-12 11:53:49 +00:00

123 lines
3.6 KiB
C

/*-
* SPDX-License-Identifier: BSD-2-Clause-FreeBSD
*
* Copyright (c) 2018 The FreeBSD Foundation
* All rights reserved.
*
* This software was developed by Konstantin Belousov <kib@FreeBSD.org>
* under sponsorship from the FreeBSD Foundation.
*
* 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("$FreeBSD$");
/* $Id: vm86_test.c,v 1.10 2018/05/12 11:35:58 kostik Exp kostik $ */
#include <sys/param.h>
#include <sys/mman.h>
#include <sys/ucontext.h>
#include <machine/cpufunc.h>
#include <machine/psl.h>
#include <machine/sysarch.h>
#include <machine/vm86.h>
#include <err.h>
#include <signal.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
static u_int gs;
static void
sig_handler(int signo, siginfo_t *si __unused, void *ucp)
{
ucontext_t *uc;
mcontext_t *mc;
uc = ucp;
mc = &uc->uc_mcontext;
/*
* Reload pointer to the TLS base, so that malloc inside
* printf() works.
*/
load_gs(gs);
printf("sig %d %%eax %#x %%ecx %#x %%eip %#x\n", signo,
mc->mc_eax, mc->mc_ecx, mc->mc_eip);
exit(0);
}
extern char vm86_code_start[], vm86_code_end[];
int
main(void)
{
ucontext_t uc;
struct sigaction sa;
struct vm86_init_args va;
stack_t ssa;
char *vm86_code;
gs = rgs();
memset(&ssa, 0, sizeof(ssa));
ssa.ss_size = PAGE_SIZE * 128;
ssa.ss_sp = mmap(NULL, ssa.ss_size, PROT_READ | PROT_WRITE |
PROT_EXEC, MAP_ANON, -1, 0);
if (ssa.ss_sp == MAP_FAILED)
err(1, "mmap sigstack");
if (sigaltstack(&ssa, NULL) == -1)
err(1, "sigaltstack");
memset(&sa, 0, sizeof(sa));
sa.sa_sigaction = sig_handler;
sa.sa_flags = SA_SIGINFO | SA_ONSTACK;
if (sigaction(SIGBUS, &sa, NULL) == -1)
err(1, "sigaction SIGBUS");
if (sigaction(SIGSEGV, &sa, NULL) == -1)
err(1, "sigaction SIGSEGV");
if (sigaction(SIGILL, &sa, NULL) == -1)
err(1, "sigaction SIGILL");
vm86_code = mmap((void *)0x10000, PAGE_SIZE, PROT_READ | PROT_WRITE |
PROT_EXEC, MAP_ANON | MAP_FIXED, -1, 0);
if (vm86_code == MAP_FAILED)
err(1, "mmap");
memcpy(vm86_code, vm86_code_start, vm86_code_end - vm86_code_start);
memset(&va, 0, sizeof(va));
if (i386_vm86(VM86_INIT, &va) == -1)
err(1, "VM86_INIT");
memset(&uc, 0, sizeof(uc));
uc.uc_mcontext.mc_ecx = 0x2345;
uc.uc_mcontext.mc_eflags = PSL_VM | PSL_USER;
uc.uc_mcontext.mc_cs = uc.uc_mcontext.mc_ds = uc.uc_mcontext.mc_es =
uc.uc_mcontext.mc_ss = (uintptr_t)vm86_code >> 4;
uc.uc_mcontext.mc_esp = 0xfffe;
sigreturn(&uc);
}