xref: /qemu/bsd-user/strace.c (revision d0fb9657)
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 #include <ctype.h>
24 
25 #include "qemu.h"
26 
27 #include "os-strace.h"  /* OS dependent strace print functions */
28 
29 int do_strace;
30 
31 /*
32  * Utility functions
33  */
34 
35 static void print_sysctl(const struct syscallname *name, abi_long arg1,
36         abi_long arg2, abi_long arg3, abi_long arg4, abi_long arg5,
37         abi_long arg6)
38 {
39     uint32_t i;
40     int32_t *namep;
41 
42     gemu_log("%s({ ", name->name);
43     namep = lock_user(VERIFY_READ, arg1, sizeof(int32_t) * arg2, 1);
44     if (namep) {
45         int32_t *p = namep;
46 
47         for (i = 0; i < (uint32_t)arg2; i++) {
48             gemu_log("%d ", tswap32(*p++));
49         }
50         unlock_user(namep, arg1, 0);
51     }
52     gemu_log("}, %u, 0x" TARGET_ABI_FMT_lx ", 0x" TARGET_ABI_FMT_lx ", 0x"
53         TARGET_ABI_FMT_lx ", 0x" TARGET_ABI_FMT_lx ")",
54         (uint32_t)arg2, arg3, arg4, arg5, arg6);
55 }
56 
57 static void print_execve(const struct syscallname *name, abi_long arg1,
58         abi_long arg2, abi_long arg3, abi_long arg4, abi_long arg5,
59         abi_long arg6)
60 {
61     abi_ulong arg_ptr_addr;
62     char *s;
63 
64     s = lock_user_string(arg1);
65     if (s == NULL) {
66         return;
67     }
68     gemu_log("%s(\"%s\",{", name->name, s);
69     unlock_user(s, arg1, 0);
70 
71     for (arg_ptr_addr = arg2; ; arg_ptr_addr += sizeof(abi_ulong)) {
72         abi_ulong *arg_ptr, arg_addr;
73 
74         arg_ptr = lock_user(VERIFY_READ, arg_ptr_addr, sizeof(abi_ulong), 1);
75         if (!arg_ptr) {
76             return;
77         }
78         arg_addr = tswapl(*arg_ptr);
79         unlock_user(arg_ptr, arg_ptr_addr, 0);
80         if (!arg_addr) {
81             break;
82         }
83         if ((s = lock_user_string(arg_addr))) {
84             gemu_log("\"%s\",", s);
85             unlock_user(s, arg_addr, 0);
86         }
87     }
88     gemu_log("NULL})");
89 }
90 
91 static void print_ioctl(const struct syscallname *name,
92         abi_long arg1, abi_long arg2, abi_long arg3, abi_long arg4,
93         abi_long arg5, abi_long arg6)
94 {
95     /* Decode the ioctl request */
96     gemu_log("%s(%d, 0x%0lx { IO%s%s GRP:0x%x('%c') CMD:%d LEN:%d }, 0x"
97             TARGET_ABI_FMT_lx ", ...)",
98             name->name,
99             (int)arg1,
100             (unsigned long)arg2,
101             arg2 & IOC_OUT ? "R" : "",
102             arg2 & IOC_IN ? "W" : "",
103             (unsigned)IOCGROUP(arg2),
104             isprint(IOCGROUP(arg2)) ? (char)IOCGROUP(arg2) : '?',
105             (int)arg2 & 0xFF,
106             (int)IOCPARM_LEN(arg2),
107             arg3);
108 }
109 
110 static void print_sysarch(const struct syscallname *name, abi_long arg1,
111         abi_long arg2, abi_long arg3, abi_long arg4, abi_long arg5,
112         abi_long arg6)
113 {
114     /* This is os dependent. */
115     do_os_print_sysarch(name, arg1, arg2, arg3, arg4, arg5, arg6);
116 }
117 
118 /*
119  * Variants for the return value output function
120  */
121 
122 static void print_syscall_ret_addr(const struct syscallname *name, abi_long ret)
123 {
124     if (ret == -1) {
125         gemu_log(" = -1 errno=%d (%s)\n", errno, strerror(errno));
126     } else {
127         gemu_log(" = 0x" TARGET_ABI_FMT_lx "\n", ret);
128     }
129 }
130 
131 /*
132  * An array of all of the syscalls we know about
133  */
134 
135 static const struct syscallname freebsd_scnames[] = {
136 #include "freebsd/strace.list"
137 };
138 static const struct syscallname netbsd_scnames[] = {
139 #include "netbsd/strace.list"
140 };
141 static const struct syscallname openbsd_scnames[] = {
142 #include "openbsd/strace.list"
143 };
144 
145 static void print_syscall(int num, const struct syscallname *scnames,
146         unsigned int nscnames, abi_long arg1, abi_long arg2, abi_long arg3,
147         abi_long arg4, abi_long arg5, abi_long arg6)
148 {
149     unsigned int i;
150     const char *format="%s(" TARGET_ABI_FMT_ld "," TARGET_ABI_FMT_ld ","
151         TARGET_ABI_FMT_ld "," TARGET_ABI_FMT_ld "," TARGET_ABI_FMT_ld ","
152         TARGET_ABI_FMT_ld ")";
153 
154     gemu_log("%d ", getpid() );
155 
156     for (i = 0; i < nscnames; i++) {
157         if (scnames[i].nr == num) {
158             if (scnames[i].call != NULL) {
159                 scnames[i].call(&scnames[i], arg1, arg2, arg3, arg4, arg5,
160                         arg6);
161             } else {
162                 /* XXX: this format system is broken because it uses
163                    host types and host pointers for strings */
164                 if (scnames[i].format != NULL) {
165                     format = scnames[i].format;
166                 }
167                 gemu_log(format, scnames[i].name, arg1, arg2, arg3, arg4, arg5,
168                         arg6);
169             }
170             return;
171         }
172     }
173     gemu_log("Unknown syscall %d\n", num);
174 }
175 
176 static void print_syscall_ret(int num, abi_long ret,
177         const struct syscallname *scnames, unsigned int nscnames)
178 {
179     unsigned int i;
180 
181     for (i = 0; i < nscnames; i++) {
182         if (scnames[i].nr == num) {
183             if (scnames[i].result != NULL) {
184                 scnames[i].result(&scnames[i], ret);
185             } else {
186                 if (ret < 0) {
187                     gemu_log(" = -1 errno=" TARGET_ABI_FMT_ld " (%s)\n", -ret,
188                              strerror(-ret));
189                 } else {
190                     gemu_log(" = " TARGET_ABI_FMT_ld "\n", ret);
191                 }
192             }
193             break;
194         }
195     }
196 }
197 
198 /*
199  * The public interface to this module.
200  */
201 void print_freebsd_syscall(int num, abi_long arg1, abi_long arg2, abi_long arg3,
202         abi_long arg4, abi_long arg5, abi_long arg6)
203 {
204 
205     print_syscall(num, freebsd_scnames, ARRAY_SIZE(freebsd_scnames), arg1, arg2,
206             arg3, arg4, arg5, arg6);
207 }
208 
209 void print_freebsd_syscall_ret(int num, abi_long ret)
210 {
211 
212     print_syscall_ret(num, ret, freebsd_scnames, ARRAY_SIZE(freebsd_scnames));
213 }
214 
215 void print_netbsd_syscall(int num, abi_long arg1, abi_long arg2, abi_long arg3,
216         abi_long arg4, abi_long arg5, abi_long arg6)
217 {
218 
219     print_syscall(num, netbsd_scnames, ARRAY_SIZE(netbsd_scnames),
220                   arg1, arg2, arg3, arg4, arg5, arg6);
221 }
222 
223 void print_netbsd_syscall_ret(int num, abi_long ret)
224 {
225 
226     print_syscall_ret(num, ret, netbsd_scnames, ARRAY_SIZE(netbsd_scnames));
227 }
228 
229 void print_openbsd_syscall(int num, abi_long arg1, abi_long arg2, abi_long arg3,
230         abi_long arg4, abi_long arg5, abi_long arg6)
231 {
232 
233     print_syscall(num, openbsd_scnames, ARRAY_SIZE(openbsd_scnames), arg1, arg2,
234             arg3, arg4, arg5, arg6);
235 }
236 
237 void print_openbsd_syscall_ret(int num, abi_long ret)
238 {
239 
240     print_syscall_ret(num, ret, openbsd_scnames, ARRAY_SIZE(openbsd_scnames));
241 }
242