amd64-freebsd32.c revision 331722 
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: stable/11/usr.bin/truss/amd64-freebsd32.c 331722 2018-03-29 02:50:57Z eadler $");
34
35/* FreeBSD/amd64-freebsd32-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 <stdbool.h>
44#include <stdio.h>
45#include <stdlib.h>
46#include <sysdecode.h>
47
48#include "truss.h"
49
50static int
51amd64_freebsd32_fetch_args(struct trussinfo *trussinfo, u_int narg)
52{
53	struct ptrace_io_desc iorequest;
54	struct reg regs;
55	struct current_syscall *cs;
56	unsigned int args32[narg];
57	unsigned long parm_offset;
58	lwpid_t tid;
59	u_int i;
60
61	tid = trussinfo->curthread->tid;
62	cs = &trussinfo->curthread->cs;
63	if (ptrace(PT_GETREGS, tid, (caddr_t)&regs, 0) < 0) {
64		fprintf(trussinfo->outfile, "-- CANNOT READ REGISTERS --\n");
65		return (-1);
66	}
67	parm_offset = regs.r_rsp + sizeof(int);
68
69	/*
70	 * FreeBSD has two special kinds of system call redirections --
71	 * SYS_syscall, and SYS___syscall.  The former is the old syscall()
72	 * routine, basically; the latter is for quad-aligned arguments.
73	 *
74	 * The system call argument count and code from ptrace() already
75	 * account for these, but we need to skip over the first argument.
76	 */
77	switch (regs.r_rax) {
78	case SYS_syscall:
79		parm_offset += sizeof(int);
80		break;
81	case SYS___syscall:
82		parm_offset += sizeof(quad_t);
83		break;
84	}
85
86	iorequest.piod_op = PIOD_READ_D;
87	iorequest.piod_offs = (void *)parm_offset;
88	iorequest.piod_addr = args32;
89	iorequest.piod_len = sizeof(args32);
90	ptrace(PT_IO, tid, (caddr_t)&iorequest, 0);
91	if (iorequest.piod_len == 0) {
92		return (-1);
93	}
94
95	for (i = 0; i < narg; i++)
96		 cs->args[i] = args32[i];
97	return (0);
98}
99
100static int
101amd64_freebsd32_fetch_retval(struct trussinfo *trussinfo, long *retval,
102    int *errorp)
103{
104	struct reg regs;
105	lwpid_t tid;
106
107	tid = trussinfo->curthread->tid;
108	if (ptrace(PT_GETREGS, tid, (caddr_t)&regs, 0) < 0) {
109		fprintf(trussinfo->outfile, "-- CANNOT READ REGISTERS --\n");
110		return (-1);
111	}
112
113	retval[0] = regs.r_rax & 0xffffffff;
114	retval[1] = regs.r_rdx & 0xffffffff;
115	*errorp = !!(regs.r_rflags & PSL_C);
116	return (0);
117}
118
119static struct procabi amd64_freebsd32 = {
120	"FreeBSD ELF32",
121	SYSDECODE_ABI_FREEBSD32,
122	amd64_freebsd32_fetch_args,
123	amd64_freebsd32_fetch_retval,
124	STAILQ_HEAD_INITIALIZER(amd64_freebsd32.extra_syscalls),
125	{ NULL }
126};
127
128PROCABI(amd64_freebsd32);
129
130static struct procabi amd64_freebsd32_aout = {
131	"FreeBSD a.out",
132	SYSDECODE_ABI_FREEBSD32,
133	amd64_freebsd32_fetch_args,
134	amd64_freebsd32_fetch_retval,
135	STAILQ_HEAD_INITIALIZER(amd64_freebsd32.extra_syscalls),
136	{ NULL }
137};
138
139PROCABI(amd64_freebsd32_aout);
140