1/*
2 * Copyright 1997 Sean Eric Fagan
3 *
4 * Redistribution and use in source and binary forms, with or without
5 * modification, are permitted provided that the following conditions
6 * are met:
7 * 1. Redistributions of source code must retain the above copyright
8 *    notice, this list of conditions and the following disclaimer.
9 * 2. Redistributions in binary form must reproduce the above copyright
10 *    notice, this list of conditions and the following disclaimer in the
11 *    documentation and/or other materials provided with the distribution.
12 * 3. All advertising materials mentioning features or use of this software
13 *    must display the following acknowledgement:
14 *	This product includes software developed by Sean Eric Fagan
15 * 4. Neither the name of the author may be used to endorse or promote
16 *    products derived from this software without specific prior written
17 *    permission.
18 *
19 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
20 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
21 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
22 * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
23 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
24 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
25 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
26 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
27 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
28 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
29 * SUCH DAMAGE.
30 */
31
32#include <sys/cdefs.h>
33__FBSDID("$FreeBSD: releng/11.0/usr.bin/truss/i386-freebsd.c 295056 2016-01-30 01:00:54Z jhb $");
34
35/* FreeBSD/i386-specific system call handling. */
36
37#include <sys/ptrace.h>
38#include <sys/syscall.h>
39
40#include <machine/reg.h>
41#include <machine/psl.h>
42
43#include <stdio.h>
44#include <sysdecode.h>
45
46#include "truss.h"
47
48static int
49i386_fetch_args(struct trussinfo *trussinfo, u_int narg)
50{
51	struct ptrace_io_desc iorequest;
52	struct reg regs;
53	struct current_syscall *cs;
54	lwpid_t tid;
55	unsigned int parm_offset;
56
57	tid = trussinfo->curthread->tid;
58	cs = &trussinfo->curthread->cs;
59	if (ptrace(PT_GETREGS, tid, (caddr_t)&regs, 0) < 0) {
60		fprintf(trussinfo->outfile, "-- CANNOT READ REGISTERS --\n");
61		return (-1);
62	}
63	parm_offset = regs.r_esp + sizeof(int);
64
65	/*
66	 * FreeBSD has two special kinds of system call redirections --
67	 * SYS_syscall, and SYS___syscall.  The former is the old syscall()
68	 * routine, basically; the latter is for quad-aligned arguments.
69	 *
70	 * The system call argument count and code from ptrace() already
71	 * account for these, but we need to skip over the first argument.
72	 */
73	switch (regs.r_eax) {
74	case SYS_syscall:
75		parm_offset += sizeof(int);
76		break;
77	case SYS___syscall:
78		parm_offset += sizeof(quad_t);
79		break;
80	}
81
82	iorequest.piod_op = PIOD_READ_D;
83	iorequest.piod_offs = (void *)parm_offset;
84	iorequest.piod_addr = cs->args;
85	iorequest.piod_len = narg * sizeof(unsigned long);
86	ptrace(PT_IO, tid, (caddr_t)&iorequest, 0);
87	if (iorequest.piod_len == 0)
88		return (-1);
89
90	return (0);
91}
92
93static int
94i386_fetch_retval(struct trussinfo *trussinfo, long *retval, int *errorp)
95{
96	struct reg regs;
97	lwpid_t tid;
98
99	tid = trussinfo->curthread->tid;
100	if (ptrace(PT_GETREGS, tid, (caddr_t)&regs, 0) < 0) {
101		fprintf(trussinfo->outfile, "-- CANNOT READ REGISTERS --\n");
102		return (-1);
103	}
104
105	retval[0] = regs.r_eax;
106	retval[1] = regs.r_edx;
107	*errorp = !!(regs.r_eflags & PSL_C);
108	return (0);
109}
110
111static struct procabi i386_freebsd = {
112	"FreeBSD ELF32",
113	SYSDECODE_ABI_FREEBSD,
114	i386_fetch_args,
115	i386_fetch_retval
116};
117
118PROCABI(i386_freebsd);
119
120static struct procabi i386_freebsd_aout = {
121	"FreeBSD a.out",
122	SYSDECODE_ABI_FREEBSD,
123	i386_fetch_args,
124	i386_fetch_retval
125};
126
127PROCABI(i386_freebsd_aout);
128
129