xref: /openbmc/qemu/bsd-user/strace.c (revision 93e0932b)
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 #include "os-strace.h"  /* OS dependent strace print functions */
27 
28 int do_strace;
29 
30 /*
31  * Utility functions
32  */
33 static const char *
34 get_comma(int last)
35 {
36     return (last) ? "" : ",";
37 }
38 
39 /*
40  * Prints out raw parameter using given format.  Caller needs
41  * to do byte swapping if needed.
42  */
43 static void
44 print_raw_param(const char *fmt, abi_long param, int last)
45 {
46     char format[64];
47 
48     (void)snprintf(format, sizeof(format), "%s%s", fmt, get_comma(last));
49     gemu_log(format, param);
50 }
51 
52 static void print_sysctl(const struct syscallname *name, abi_long arg1,
53         abi_long arg2, abi_long arg3, abi_long arg4, abi_long arg5,
54         abi_long arg6)
55 {
56     uint32_t i;
57     int32_t *namep;
58 
59     gemu_log("%s({ ", name->name);
60     namep = lock_user(VERIFY_READ, arg1, sizeof(int32_t) * arg2, 1);
61     if (namep) {
62         int32_t *p = namep;
63 
64         for (i = 0; i < (uint32_t)arg2; i++) {
65             gemu_log("%d ", tswap32(*p++));
66         }
67         unlock_user(namep, arg1, 0);
68     }
69     gemu_log("}, %u, 0x" TARGET_ABI_FMT_lx ", 0x" TARGET_ABI_FMT_lx ", 0x"
70         TARGET_ABI_FMT_lx ", 0x" TARGET_ABI_FMT_lx ")",
71         (uint32_t)arg2, arg3, arg4, arg5, arg6);
72 }
73 
74 static void print_execve(const struct syscallname *name, abi_long arg1,
75         abi_long arg2, abi_long arg3, abi_long arg4, abi_long arg5,
76         abi_long arg6)
77 {
78     abi_ulong arg_ptr_addr;
79     char *s;
80 
81     s = lock_user_string(arg1);
82     if (s == NULL) {
83         return;
84     }
85     gemu_log("%s(\"%s\",{", name->name, s);
86     unlock_user(s, arg1, 0);
87 
88     for (arg_ptr_addr = arg2; ; arg_ptr_addr += sizeof(abi_ulong)) {
89         abi_ulong *arg_ptr, arg_addr;
90 
91         arg_ptr = lock_user(VERIFY_READ, arg_ptr_addr, sizeof(abi_ulong), 1);
92         if (!arg_ptr) {
93             return;
94         }
95         arg_addr = tswapl(*arg_ptr);
96         unlock_user(arg_ptr, arg_ptr_addr, 0);
97         if (!arg_addr) {
98             break;
99         }
100         if ((s = lock_user_string(arg_addr))) {
101             gemu_log("\"%s\",", s);
102             unlock_user(s, arg_addr, 0);
103         }
104     }
105     gemu_log("NULL})");
106 }
107 
108 static void print_ioctl(const struct syscallname *name,
109         abi_long arg1, abi_long arg2, abi_long arg3, abi_long arg4,
110         abi_long arg5, abi_long arg6)
111 {
112     /* Decode the ioctl request */
113     gemu_log("%s(%d, 0x%0lx { IO%s%s GRP:0x%x('%c') CMD:%d LEN:%d }, 0x"
114             TARGET_ABI_FMT_lx ", ...)",
115             name->name,
116             (int)arg1,
117             (unsigned long)arg2,
118             arg2 & IOC_OUT ? "R" : "",
119             arg2 & IOC_IN ? "W" : "",
120             (unsigned)IOCGROUP(arg2),
121             isprint(IOCGROUP(arg2)) ? (char)IOCGROUP(arg2) : '?',
122             (int)arg2 & 0xFF,
123             (int)IOCPARM_LEN(arg2),
124             arg3);
125 }
126 
127 static void print_sysarch(const struct syscallname *name, abi_long arg1,
128         abi_long arg2, abi_long arg3, abi_long arg4, abi_long arg5,
129         abi_long arg6)
130 {
131     /* This is os dependent. */
132     do_os_print_sysarch(name, arg1, arg2, arg3, arg4, arg5, arg6);
133 }
134 
135 /*
136  * Variants for the return value output function
137  */
138 
139 static void print_syscall_ret_addr(const struct syscallname *name, abi_long ret)
140 {
141     if (ret == -1) {
142         gemu_log(" = -1 errno=%d (%s)\n", errno, strerror(errno));
143     } else {
144         gemu_log(" = 0x" TARGET_ABI_FMT_lx "\n", ret);
145     }
146 }
147 
148 /*
149  * An array of all of the syscalls we know about
150  */
151 
152 static const struct syscallname freebsd_scnames[] = {
153 #include "freebsd/strace.list"
154 };
155 static const struct syscallname netbsd_scnames[] = {
156 #include "netbsd/strace.list"
157 };
158 static const struct syscallname openbsd_scnames[] = {
159 #include "openbsd/strace.list"
160 };
161 
162 static void print_syscall(int num, const struct syscallname *scnames,
163         unsigned int nscnames, abi_long arg1, abi_long arg2, abi_long arg3,
164         abi_long arg4, abi_long arg5, abi_long arg6)
165 {
166     unsigned int i;
167     const char *format="%s(" TARGET_ABI_FMT_ld "," TARGET_ABI_FMT_ld ","
168         TARGET_ABI_FMT_ld "," TARGET_ABI_FMT_ld "," TARGET_ABI_FMT_ld ","
169         TARGET_ABI_FMT_ld ")";
170 
171     gemu_log("%d ", getpid() );
172 
173     for (i = 0; i < nscnames; i++) {
174         if (scnames[i].nr == num) {
175             if (scnames[i].call != NULL) {
176                 scnames[i].call(&scnames[i], arg1, arg2, arg3, arg4, arg5,
177                         arg6);
178             } else {
179                 /* XXX: this format system is broken because it uses
180                    host types and host pointers for strings */
181                 if (scnames[i].format != NULL) {
182                     format = scnames[i].format;
183                 }
184                 gemu_log(format, scnames[i].name, arg1, arg2, arg3, arg4, arg5,
185                         arg6);
186             }
187             return;
188         }
189     }
190     gemu_log("Unknown syscall %d\n", num);
191 }
192 
193 static void print_syscall_ret(int num, abi_long ret,
194         const struct syscallname *scnames, unsigned int nscnames)
195 {
196     unsigned int i;
197 
198     for (i = 0; i < nscnames; i++) {
199         if (scnames[i].nr == num) {
200             if (scnames[i].result != NULL) {
201                 scnames[i].result(&scnames[i], ret);
202             } else {
203                 if (ret < 0) {
204                     gemu_log(" = -1 errno=" TARGET_ABI_FMT_ld " (%s)\n", -ret,
205                              strerror(-ret));
206                 } else {
207                     gemu_log(" = " TARGET_ABI_FMT_ld "\n", ret);
208                 }
209             }
210             break;
211         }
212     }
213 }
214 
215 /*
216  * The public interface to this module.
217  */
218 void print_freebsd_syscall(int num, abi_long arg1, abi_long arg2, abi_long arg3,
219         abi_long arg4, abi_long arg5, abi_long arg6)
220 {
221 
222     print_syscall(num, freebsd_scnames, ARRAY_SIZE(freebsd_scnames), arg1, arg2,
223             arg3, arg4, arg5, arg6);
224 }
225 
226 void print_freebsd_syscall_ret(int num, abi_long ret)
227 {
228 
229     print_syscall_ret(num, ret, freebsd_scnames, ARRAY_SIZE(freebsd_scnames));
230 }
231 
232 void print_netbsd_syscall(int num, abi_long arg1, abi_long arg2, abi_long arg3,
233         abi_long arg4, abi_long arg5, abi_long arg6)
234 {
235 
236     print_syscall(num, netbsd_scnames, ARRAY_SIZE(netbsd_scnames),
237                   arg1, arg2, arg3, arg4, arg5, arg6);
238 }
239 
240 void print_netbsd_syscall_ret(int num, abi_long ret)
241 {
242 
243     print_syscall_ret(num, ret, netbsd_scnames, ARRAY_SIZE(netbsd_scnames));
244 }
245 
246 void print_openbsd_syscall(int num, abi_long arg1, abi_long arg2, abi_long arg3,
247         abi_long arg4, abi_long arg5, abi_long arg6)
248 {
249 
250     print_syscall(num, openbsd_scnames, ARRAY_SIZE(openbsd_scnames), arg1, arg2,
251             arg3, arg4, arg5, arg6);
252 }
253 
254 void print_openbsd_syscall_ret(int num, abi_long ret)
255 {
256 
257     print_syscall_ret(num, ret, openbsd_scnames, ARRAY_SIZE(openbsd_scnames));
258 }
259 
260 static void
261 print_signal(abi_ulong arg, int last)
262 {
263     const char *signal_name = NULL;
264     switch (arg) {
265     case TARGET_SIGHUP:
266         signal_name = "SIGHUP";
267         break;
268     case TARGET_SIGINT:
269         signal_name = "SIGINT";
270         break;
271     case TARGET_SIGQUIT:
272         signal_name = "SIGQUIT";
273         break;
274     case TARGET_SIGILL:
275         signal_name = "SIGILL";
276         break;
277     case TARGET_SIGABRT:
278         signal_name = "SIGABRT";
279         break;
280     case TARGET_SIGFPE:
281         signal_name = "SIGFPE";
282         break;
283     case TARGET_SIGKILL:
284         signal_name = "SIGKILL";
285         break;
286     case TARGET_SIGSEGV:
287         signal_name = "SIGSEGV";
288         break;
289     case TARGET_SIGPIPE:
290         signal_name = "SIGPIPE";
291         break;
292     case TARGET_SIGALRM:
293         signal_name = "SIGALRM";
294         break;
295     case TARGET_SIGTERM:
296         signal_name = "SIGTERM";
297         break;
298     case TARGET_SIGUSR1:
299         signal_name = "SIGUSR1";
300         break;
301     case TARGET_SIGUSR2:
302         signal_name = "SIGUSR2";
303         break;
304     case TARGET_SIGCHLD:
305         signal_name = "SIGCHLD";
306         break;
307     case TARGET_SIGCONT:
308         signal_name = "SIGCONT";
309         break;
310     case TARGET_SIGSTOP:
311         signal_name = "SIGSTOP";
312         break;
313     case TARGET_SIGTTIN:
314         signal_name = "SIGTTIN";
315         break;
316     case TARGET_SIGTTOU:
317         signal_name = "SIGTTOU";
318         break;
319     }
320     if (signal_name == NULL) {
321         print_raw_param("%ld", arg, last);
322         return;
323     }
324     gemu_log("%s%s", signal_name, get_comma(last));
325 }
326 
327 void print_taken_signal(int target_signum, const target_siginfo_t *tinfo)
328 {
329     /*
330      * Print the strace output for a signal being taken:
331      * --- SIGSEGV {si_signo=SIGSEGV, si_code=SI_KERNEL, si_addr=0} ---
332      */
333     gemu_log("%d ", getpid());
334     gemu_log("--- ");
335     print_signal(target_signum, 1);
336     gemu_log(" ---\n");
337 }
338