xref: /openbmc/qemu/bsd-user/strace.c (revision 09a274d8)
1 /*
2  *  System call tracing and debugging
3  *
4  *
5  *  This program is free software; you can redistribute it and/or modify
6  *  it under the terms of the GNU General Public License as published by
7  *  the Free Software Foundation; either version 2 of the License, or
8  *  (at your option) any later version.
9  *
10  *  This program is distributed in the hope that it will be useful,
11  *  but WITHOUT ANY WARRANTY; without even the implied warranty of
12  *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
13  *  GNU General Public License for more details.
14  *
15  *  You should have received a copy of the GNU General Public License
16  *  along with this program; if not, see <http://www.gnu.org/licenses/>.
17  */
18 
19 #include "qemu/osdep.h"
20 #include <sys/select.h>
21 #include <sys/syscall.h>
22 #include <sys/ioccom.h>
23 
24 #include "qemu.h"
25 
26 int do_strace;
27 
28 /*
29  * Utility functions
30  */
31 
32 static void print_sysctl(const struct syscallname *name, abi_long arg1,
33         abi_long arg2, abi_long arg3, abi_long arg4, abi_long arg5,
34         abi_long arg6)
35 {
36     uint32_t i;
37     int32_t *namep;
38 
39     gemu_log("%s({ ", name->name);
40     namep = lock_user(VERIFY_READ, arg1, sizeof(int32_t) * arg2, 1);
41     if (namep) {
42         int32_t *p = namep;
43 
44         for (i = 0; i < (uint32_t)arg2; i++) {
45             gemu_log("%d ", tswap32(*p++));
46         }
47         unlock_user(namep, arg1, 0);
48     }
49     gemu_log("}, %u, 0x" TARGET_ABI_FMT_lx ", 0x" TARGET_ABI_FMT_lx ", 0x"
50         TARGET_ABI_FMT_lx ", 0x" TARGET_ABI_FMT_lx ")",
51         (uint32_t)arg2, arg3, arg4, arg5, arg6);
52 }
53 
54 static void print_execve(const struct syscallname *name, abi_long arg1,
55         abi_long arg2, abi_long arg3, abi_long arg4, abi_long arg5,
56         abi_long arg6)
57 {
58     abi_ulong arg_ptr_addr;
59     char *s;
60 
61     s = lock_user_string(arg1);
62     if (s == NULL) {
63         return;
64     }
65     gemu_log("%s(\"%s\",{", name->name, s);
66     unlock_user(s, arg1, 0);
67 
68     for (arg_ptr_addr = arg2; ; arg_ptr_addr += sizeof(abi_ulong)) {
69         abi_ulong *arg_ptr, arg_addr;
70 
71         arg_ptr = lock_user(VERIFY_READ, arg_ptr_addr, sizeof(abi_ulong), 1);
72         if (!arg_ptr) {
73             return;
74         }
75         arg_addr = tswapl(*arg_ptr);
76         unlock_user(arg_ptr, arg_ptr_addr, 0);
77         if (!arg_addr) {
78             break;
79         }
80         if ((s = lock_user_string(arg_addr))) {
81             gemu_log("\"%s\",", s);
82             unlock_user(s, arg_addr, 0);
83         }
84     }
85     gemu_log("NULL})");
86 }
87 
88 static void print_ioctl(const struct syscallname *name,
89         abi_long arg1, abi_long arg2, abi_long arg3, abi_long arg4,
90         abi_long arg5, abi_long arg6)
91 {
92     /* Decode the ioctl request */
93     gemu_log("%s(%d, 0x%0lx { IO%s%s GRP:0x%x('%c') CMD:%d LEN:%d }, 0x"
94             TARGET_ABI_FMT_lx ", ...)",
95             name->name,
96             (int)arg1,
97             (unsigned long)arg2,
98             arg2 & IOC_OUT ? "R" : "",
99             arg2 & IOC_IN ? "W" : "",
100             (unsigned)IOCGROUP(arg2),
101             isprint(IOCGROUP(arg2)) ? (char)IOCGROUP(arg2) : '?',
102             (int)arg2 & 0xFF,
103             (int)IOCPARM_LEN(arg2),
104             arg3);
105 }
106 
107 /*
108  * Variants for the return value output function
109  */
110 
111 static void print_syscall_ret_addr(const struct syscallname *name, abi_long ret)
112 {
113     if (ret == -1) {
114         gemu_log(" = -1 errno=%d (%s)\n", errno, strerror(errno));
115     } else {
116         gemu_log(" = 0x" TARGET_ABI_FMT_lx "\n", ret);
117     }
118 }
119 
120 #if 0 /* currently unused */
121 static void
122 print_syscall_ret_raw(struct syscallname *name, abi_long ret)
123 {
124         gemu_log(" = 0x" TARGET_ABI_FMT_lx "\n", ret);
125 }
126 #endif
127 
128 /*
129  * An array of all of the syscalls we know about
130  */
131 
132 static const struct syscallname freebsd_scnames[] = {
133 #include "freebsd/strace.list"
134 };
135 static const struct syscallname netbsd_scnames[] = {
136 #include "netbsd/strace.list"
137 };
138 static const struct syscallname openbsd_scnames[] = {
139 #include "openbsd/strace.list"
140 };
141 
142 static void print_syscall(int num, const struct syscallname *scnames,
143         unsigned int nscnames, abi_long arg1, abi_long arg2, abi_long arg3,
144         abi_long arg4, abi_long arg5, abi_long arg6)
145 {
146     unsigned int i;
147     const char *format="%s(" TARGET_ABI_FMT_ld "," TARGET_ABI_FMT_ld ","
148         TARGET_ABI_FMT_ld "," TARGET_ABI_FMT_ld "," TARGET_ABI_FMT_ld ","
149         TARGET_ABI_FMT_ld ")";
150 
151     gemu_log("%d ", getpid() );
152 
153     for (i = 0; i < nscnames; i++) {
154         if (scnames[i].nr == num) {
155             if (scnames[i].call != NULL) {
156                 scnames[i].call(&scnames[i], arg1, arg2, arg3, arg4, arg5,
157                         arg6);
158             } else {
159                 /* XXX: this format system is broken because it uses
160                    host types and host pointers for strings */
161                 if (scnames[i].format != NULL) {
162                     format = scnames[i].format;
163                 }
164                 gemu_log(format, scnames[i].name, arg1, arg2, arg3, arg4, arg5,
165                         arg6);
166             }
167             return;
168         }
169     }
170     gemu_log("Unknown syscall %d\n", num);
171 }
172 
173 static void print_syscall_ret(int num, abi_long ret,
174         const struct syscallname *scnames, unsigned int nscnames)
175 {
176     unsigned int i;
177 
178     for (i = 0; i < nscnames; i++) {
179         if (scnames[i].nr == num) {
180             if (scnames[i].result != NULL) {
181                 scnames[i].result(&scnames[i], ret);
182             } else {
183                 if (ret < 0) {
184                     gemu_log(" = -1 errno=" TARGET_ABI_FMT_ld " (%s)\n", -ret,
185                              strerror(-ret));
186                 } else {
187                     gemu_log(" = " TARGET_ABI_FMT_ld "\n", ret);
188                 }
189             }
190             break;
191         }
192     }
193 }
194 
195 /*
196  * The public interface to this module.
197  */
198 void print_freebsd_syscall(int num, abi_long arg1, abi_long arg2, abi_long arg3,
199         abi_long arg4, abi_long arg5, abi_long arg6)
200 {
201 
202     print_syscall(num, freebsd_scnames, ARRAY_SIZE(freebsd_scnames), arg1, arg2,
203             arg3, arg4, arg5, arg6);
204 }
205 
206 void print_freebsd_syscall_ret(int num, abi_long ret)
207 {
208 
209     print_syscall_ret(num, ret, freebsd_scnames, ARRAY_SIZE(freebsd_scnames));
210 }
211 
212 void print_netbsd_syscall(int num, abi_long arg1, abi_long arg2, abi_long arg3,
213         abi_long arg4, abi_long arg5, abi_long arg6)
214 {
215 
216     print_syscall(num, netbsd_scnames, ARRAY_SIZE(netbsd_scnames),
217                   arg1, arg2, arg3, arg4, arg5, arg6);
218 }
219 
220 void print_netbsd_syscall_ret(int num, abi_long ret)
221 {
222 
223     print_syscall_ret(num, ret, netbsd_scnames, ARRAY_SIZE(netbsd_scnames));
224 }
225 
226 void print_openbsd_syscall(int num, abi_long arg1, abi_long arg2, abi_long arg3,
227         abi_long arg4, abi_long arg5, abi_long arg6)
228 {
229 
230     print_syscall(num, openbsd_scnames, ARRAY_SIZE(openbsd_scnames), arg1, arg2,
231             arg3, arg4, arg5, arg6);
232 }
233 
234 void print_openbsd_syscall_ret(int num, abi_long ret)
235 {
236 
237     print_syscall_ret(num, ret, openbsd_scnames, ARRAY_SIZE(openbsd_scnames));
238 }
239