1 /*-
2 * SPDX-License-Identifier: BSD-2-Clause
3 *
4 * Copyright (c) 2018 The FreeBSD Foundation
5 *
6 * This software was developed by Konstantin Belousov <kib@FreeBSD.org>
7 * under sponsorship from the FreeBSD Foundation.
8 *
9 * Redistribution and use in source and binary forms, with or without
10 * modification, are permitted provided that the following conditions
11 * are met:
12 * 1. Redistributions of source code must retain the above copyright
13 * notice, this list of conditions and the following disclaimer.
14 * 2. Redistributions in binary form must reproduce the above copyright
15 * notice, this list of conditions and the following disclaimer in the
16 * documentation and/or other materials provided with the distribution.
17 *
18 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
19 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
20 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
21 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
22 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
23 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
24 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
25 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
26 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
27 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
28 * SUCH DAMAGE.
29 */
30
31 #include <sys/cdefs.h>
32 /* $Id: vm86_test.c,v 1.10 2018/05/12 11:35:58 kostik Exp kostik $ */
33
34 #include <sys/param.h>
35 #include <sys/mman.h>
36 #include <sys/ucontext.h>
37
38 #include <machine/cpufunc.h>
39 #include <machine/psl.h>
40 #include <machine/sysarch.h>
41 #include <machine/vm86.h>
42
43 #include <err.h>
44 #include <signal.h>
45 #include <stdio.h>
46 #include <stdlib.h>
47 #include <string.h>
48
49 static u_int gs;
50
51 static void
sig_handler(int signo,siginfo_t * si __unused,void * ucp)52 sig_handler(int signo, siginfo_t *si __unused, void *ucp)
53 {
54 ucontext_t *uc;
55 mcontext_t *mc;
56
57 uc = ucp;
58 mc = &uc->uc_mcontext;
59
60 /*
61 * Reload pointer to the TLS base, so that malloc inside
62 * printf() works.
63 */
64 load_gs(gs);
65
66 printf("sig %d %%eax %#x %%ecx %#x %%eip %#x\n", signo,
67 mc->mc_eax, mc->mc_ecx, mc->mc_eip);
68 exit(0);
69 }
70
71 extern char vm86_code_start[], vm86_code_end[];
72
73 int
main(void)74 main(void)
75 {
76 ucontext_t uc;
77 struct sigaction sa;
78 struct vm86_init_args va;
79 stack_t ssa;
80 char *vm86_code;
81
82 gs = rgs();
83
84 memset(&ssa, 0, sizeof(ssa));
85 ssa.ss_size = PAGE_SIZE * 128;
86 ssa.ss_sp = mmap(NULL, ssa.ss_size, PROT_READ | PROT_WRITE |
87 PROT_EXEC, MAP_ANON, -1, 0);
88 if (ssa.ss_sp == MAP_FAILED)
89 err(1, "mmap sigstack");
90 if (sigaltstack(&ssa, NULL) == -1)
91 err(1, "sigaltstack");
92
93 memset(&sa, 0, sizeof(sa));
94 sa.sa_sigaction = sig_handler;
95 sa.sa_flags = SA_SIGINFO | SA_ONSTACK;
96 if (sigaction(SIGBUS, &sa, NULL) == -1)
97 err(1, "sigaction SIGBUS");
98 if (sigaction(SIGSEGV, &sa, NULL) == -1)
99 err(1, "sigaction SIGSEGV");
100 if (sigaction(SIGILL, &sa, NULL) == -1)
101 err(1, "sigaction SIGILL");
102
103 vm86_code = mmap((void *)0x10000, PAGE_SIZE, PROT_READ | PROT_WRITE |
104 PROT_EXEC, MAP_ANON | MAP_FIXED, -1, 0);
105 if (vm86_code == MAP_FAILED)
106 err(1, "mmap");
107 memcpy(vm86_code, vm86_code_start, vm86_code_end - vm86_code_start);
108
109 memset(&va, 0, sizeof(va));
110 if (i386_vm86(VM86_INIT, &va) == -1)
111 err(1, "VM86_INIT");
112
113 memset(&uc, 0, sizeof(uc));
114 uc.uc_mcontext.mc_ecx = 0x2345;
115 uc.uc_mcontext.mc_eflags = PSL_VM | PSL_USER;
116 uc.uc_mcontext.mc_cs = uc.uc_mcontext.mc_ds = uc.uc_mcontext.mc_es =
117 uc.uc_mcontext.mc_ss = (uintptr_t)vm86_code >> 4;
118 uc.uc_mcontext.mc_esp = 0xfffe;
119 sigreturn(&uc);
120 }
121