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 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 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