Commit | Line | Data |
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e822f505 MD |
1 | /* |
2 | * Copyright (C) 2009 Pierre-Marc Fournier | |
3678c8aa | 3 | * Copyright (C) 2011-2012 Mathieu Desnoyers <mathieu.desnoyers@efficios.com> |
2d99476b PMF |
4 | * |
5 | * This library is free software; you can redistribute it and/or | |
6 | * modify it under the terms of the GNU Lesser General Public | |
e822f505 MD |
7 | * License as published by the Free Software Foundation; version 2.1 of |
8 | * the License. | |
2d99476b PMF |
9 | * |
10 | * This library 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 GNU | |
13 | * Lesser General Public License for more details. | |
14 | * | |
15 | * You should have received a copy of the GNU Lesser General Public | |
16 | * License along with this library; if not, write to the Free Software | |
17 | * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA | |
18 | */ | |
19 | ||
20 | #define _GNU_SOURCE | |
f02baefb | 21 | #include <lttng/ust-dlfcn.h> |
2d99476b PMF |
22 | #include <unistd.h> |
23 | #include <stdio.h> | |
df793c55 | 24 | #include <signal.h> |
616ed36a PMF |
25 | #include <sched.h> |
26 | #include <stdarg.h> | |
eb2b066f | 27 | #include <errno.h> |
2d99476b | 28 | |
4318ae1b | 29 | #include <lttng/ust.h> |
e822f505 | 30 | |
2d99476b PMF |
31 | pid_t fork(void) |
32 | { | |
33 | static pid_t (*plibc_func)(void) = NULL; | |
7f0aeeba | 34 | sigset_t sigset; |
2d99476b | 35 | pid_t retval; |
111902ab | 36 | int saved_errno; |
2d99476b | 37 | |
e822f505 | 38 | if (plibc_func == NULL) { |
2d99476b | 39 | plibc_func = dlsym(RTLD_NEXT, "fork"); |
e822f505 MD |
40 | if (plibc_func == NULL) { |
41 | fprintf(stderr, "libustfork: unable to find \"fork\" symbol\n"); | |
3678c8aa | 42 | errno = ENOSYS; |
2c10b7fd | 43 | return -1; |
2d99476b PMF |
44 | } |
45 | } | |
46 | ||
7f0aeeba | 47 | ust_before_fork(&sigset); |
df793c55 | 48 | /* Do the real fork */ |
2d99476b | 49 | retval = plibc_func(); |
111902ab | 50 | saved_errno = errno; |
e822f505 | 51 | if (retval == 0) { |
df793c55 | 52 | /* child */ |
7f0aeeba | 53 | ust_after_fork_child(&sigset); |
e822f505 | 54 | } else { |
7f0aeeba | 55 | ust_after_fork_parent(&sigset); |
df793c55 | 56 | } |
111902ab | 57 | errno = saved_errno; |
2d99476b PMF |
58 | return retval; |
59 | } | |
97b042a3 | 60 | |
2f6150e9 MD |
61 | int daemon(int nochdir, int noclose) |
62 | { | |
63 | static int (*plibc_func)(int nochdir, int noclose) = NULL; | |
64 | sigset_t sigset; | |
65 | int retval; | |
111902ab | 66 | int saved_errno; |
2f6150e9 MD |
67 | |
68 | if (plibc_func == NULL) { | |
69 | plibc_func = dlsym(RTLD_NEXT, "daemon"); | |
70 | if (plibc_func == NULL) { | |
71 | fprintf(stderr, "libustfork: unable to find \"daemon\" symbol\n"); | |
72 | errno = ENOSYS; | |
73 | return -1; | |
74 | } | |
75 | } | |
76 | ||
77 | ust_before_fork(&sigset); | |
78 | /* Do the real daemon call */ | |
79 | retval = plibc_func(nochdir, noclose); | |
111902ab | 80 | saved_errno = errno; |
2f6150e9 MD |
81 | if (retval == 0) { |
82 | /* child, parent called _exit() directly */ | |
83 | ust_after_fork_child(&sigset); | |
84 | } else { | |
85 | /* on error in the parent */ | |
86 | ust_after_fork_parent(&sigset); | |
87 | } | |
111902ab | 88 | errno = saved_errno; |
2f6150e9 MD |
89 | return retval; |
90 | } | |
91 | ||
fca2f191 MJ |
92 | int setuid(uid_t uid) |
93 | { | |
94 | static int (*plibc_func)(uid_t uid) = NULL; | |
95 | int retval; | |
96 | int saved_errno; | |
97 | ||
98 | if (plibc_func == NULL) { | |
99 | plibc_func = dlsym(RTLD_NEXT, "setuid"); | |
100 | if (plibc_func == NULL) { | |
101 | fprintf(stderr, "libustfork: unable to find \"setuid\" symbol\n"); | |
102 | errno = ENOSYS; | |
103 | return -1; | |
104 | } | |
105 | } | |
106 | ||
107 | /* Do the real setuid */ | |
108 | retval = plibc_func(uid); | |
109 | saved_errno = errno; | |
110 | ||
111 | ust_after_setuid(); | |
112 | ||
113 | errno = saved_errno; | |
114 | return retval; | |
115 | } | |
116 | ||
117 | int setgid(gid_t gid) | |
118 | { | |
119 | static int (*plibc_func)(gid_t gid) = NULL; | |
120 | int retval; | |
121 | int saved_errno; | |
122 | ||
123 | if (plibc_func == NULL) { | |
124 | plibc_func = dlsym(RTLD_NEXT, "setgid"); | |
125 | if (plibc_func == NULL) { | |
126 | fprintf(stderr, "libustfork: unable to find \"setgid\" symbol\n"); | |
127 | errno = ENOSYS; | |
128 | return -1; | |
129 | } | |
130 | } | |
131 | ||
132 | /* Do the real setgid */ | |
133 | retval = plibc_func(gid); | |
134 | saved_errno = errno; | |
135 | ||
136 | ust_after_setgid(); | |
137 | ||
138 | errno = saved_errno; | |
139 | return retval; | |
140 | } | |
141 | ||
142 | int seteuid(uid_t euid) | |
143 | { | |
144 | static int (*plibc_func)(uid_t euid) = NULL; | |
145 | int retval; | |
146 | int saved_errno; | |
147 | ||
148 | if (plibc_func == NULL) { | |
149 | plibc_func = dlsym(RTLD_NEXT, "seteuid"); | |
150 | if (plibc_func == NULL) { | |
151 | fprintf(stderr, "libustfork: unable to find \"seteuid\" symbol\n"); | |
152 | errno = ENOSYS; | |
153 | return -1; | |
154 | } | |
155 | } | |
156 | ||
157 | /* Do the real seteuid */ | |
158 | retval = plibc_func(euid); | |
159 | saved_errno = errno; | |
160 | ||
161 | ust_after_seteuid(); | |
162 | ||
163 | errno = saved_errno; | |
164 | return retval; | |
165 | } | |
166 | ||
167 | int setegid(gid_t egid) | |
168 | { | |
169 | static int (*plibc_func)(gid_t egid) = NULL; | |
170 | int retval; | |
171 | int saved_errno; | |
172 | ||
173 | if (plibc_func == NULL) { | |
174 | plibc_func = dlsym(RTLD_NEXT, "setegid"); | |
175 | if (plibc_func == NULL) { | |
176 | fprintf(stderr, "libustfork: unable to find \"setegid\" symbol\n"); | |
177 | errno = ENOSYS; | |
178 | return -1; | |
179 | } | |
180 | } | |
181 | ||
182 | /* Do the real setegid */ | |
183 | retval = plibc_func(egid); | |
184 | saved_errno = errno; | |
185 | ||
186 | ust_after_setegid(); | |
187 | ||
188 | errno = saved_errno; | |
189 | return retval; | |
190 | } | |
191 | ||
192 | int setreuid(uid_t ruid, uid_t euid) | |
193 | { | |
194 | static int (*plibc_func)(uid_t ruid, uid_t euid) = NULL; | |
195 | int retval; | |
196 | int saved_errno; | |
197 | ||
198 | if (plibc_func == NULL) { | |
199 | plibc_func = dlsym(RTLD_NEXT, "setreuid"); | |
200 | if (plibc_func == NULL) { | |
201 | fprintf(stderr, "libustfork: unable to find \"setreuid\" symbol\n"); | |
202 | errno = ENOSYS; | |
203 | return -1; | |
204 | } | |
205 | } | |
206 | ||
207 | /* Do the real setreuid */ | |
208 | retval = plibc_func(ruid, euid); | |
209 | saved_errno = errno; | |
210 | ||
211 | ust_after_setreuid(); | |
212 | ||
213 | errno = saved_errno; | |
214 | return retval; | |
215 | } | |
216 | ||
217 | int setregid(gid_t rgid, gid_t egid) | |
218 | { | |
219 | static int (*plibc_func)(gid_t rgid, gid_t egid) = NULL; | |
220 | int retval; | |
221 | int saved_errno; | |
222 | ||
223 | if (plibc_func == NULL) { | |
224 | plibc_func = dlsym(RTLD_NEXT, "setregid"); | |
225 | if (plibc_func == NULL) { | |
226 | fprintf(stderr, "libustfork: unable to find \"setregid\" symbol\n"); | |
227 | errno = ENOSYS; | |
228 | return -1; | |
229 | } | |
230 | } | |
231 | ||
232 | /* Do the real setregid */ | |
233 | retval = plibc_func(rgid, egid); | |
234 | saved_errno = errno; | |
235 | ||
236 | ust_after_setregid(); | |
237 | ||
238 | errno = saved_errno; | |
239 | return retval; | |
240 | } | |
241 | ||
939c89cb MD |
242 | #ifdef __linux__ |
243 | ||
244 | struct user_desc; | |
245 | ||
e822f505 | 246 | struct ustfork_clone_info { |
616ed36a PMF |
247 | int (*fn)(void *); |
248 | void *arg; | |
7f0aeeba | 249 | sigset_t sigset; |
616ed36a PMF |
250 | }; |
251 | ||
252 | static int clone_fn(void *arg) | |
253 | { | |
e822f505 | 254 | struct ustfork_clone_info *info = (struct ustfork_clone_info *) arg; |
616ed36a PMF |
255 | |
256 | /* clone is now done and we are in child */ | |
7f0aeeba | 257 | ust_after_fork_child(&info->sigset); |
616ed36a PMF |
258 | return info->fn(info->arg); |
259 | } | |
260 | ||
261 | int clone(int (*fn)(void *), void *child_stack, int flags, void *arg, ...) | |
262 | { | |
e822f505 MD |
263 | static int (*plibc_func)(int (*fn)(void *), void *child_stack, |
264 | int flags, void *arg, pid_t *ptid, | |
265 | struct user_desc *tls, pid_t *ctid) = NULL; | |
266 | /* var args */ | |
616ed36a PMF |
267 | pid_t *ptid; |
268 | struct user_desc *tls; | |
269 | pid_t *ctid; | |
e822f505 | 270 | /* end of var args */ |
616ed36a | 271 | va_list ap; |
e822f505 | 272 | int retval; |
111902ab | 273 | int saved_errno; |
616ed36a PMF |
274 | |
275 | va_start(ap, arg); | |
276 | ptid = va_arg(ap, pid_t *); | |
277 | tls = va_arg(ap, struct user_desc *); | |
278 | ctid = va_arg(ap, pid_t *); | |
279 | va_end(ap); | |
280 | ||
e822f505 | 281 | if (plibc_func == NULL) { |
616ed36a | 282 | plibc_func = dlsym(RTLD_NEXT, "clone"); |
e822f505 MD |
283 | if (plibc_func == NULL) { |
284 | fprintf(stderr, "libustfork: unable to find \"clone\" symbol.\n"); | |
3678c8aa | 285 | errno = ENOSYS; |
616ed36a PMF |
286 | return -1; |
287 | } | |
288 | } | |
289 | ||
e822f505 MD |
290 | if (flags & CLONE_VM) { |
291 | /* | |
292 | * Creating a thread, no need to intervene, just pass on | |
293 | * the arguments. | |
294 | */ | |
295 | retval = plibc_func(fn, child_stack, flags, arg, ptid, | |
296 | tls, ctid); | |
111902ab | 297 | saved_errno = errno; |
e822f505 MD |
298 | } else { |
299 | /* Creating a real process, we need to intervene. */ | |
3fd2b913 | 300 | struct ustfork_clone_info info = { .fn = fn, .arg = arg }; |
616ed36a | 301 | |
7f0aeeba | 302 | ust_before_fork(&info.sigset); |
e822f505 MD |
303 | retval = plibc_func(clone_fn, child_stack, flags, &info, |
304 | ptid, tls, ctid); | |
111902ab | 305 | saved_errno = errno; |
e822f505 | 306 | /* The child doesn't get here. */ |
7f0aeeba | 307 | ust_after_fork_parent(&info.sigset); |
616ed36a | 308 | } |
111902ab | 309 | errno = saved_errno; |
616ed36a PMF |
310 | return retval; |
311 | } | |
939c89cb | 312 | |
735bef47 MJ |
313 | int setns(int fd, int nstype) |
314 | { | |
315 | static int (*plibc_func)(int fd, int nstype) = NULL; | |
316 | int retval; | |
317 | int saved_errno; | |
318 | ||
319 | if (plibc_func == NULL) { | |
320 | plibc_func = dlsym(RTLD_NEXT, "setns"); | |
321 | if (plibc_func == NULL) { | |
322 | fprintf(stderr, "libustfork: unable to find \"setns\" symbol\n"); | |
323 | errno = ENOSYS; | |
324 | return -1; | |
325 | } | |
326 | } | |
327 | ||
328 | /* Do the real setns */ | |
329 | retval = plibc_func(fd, nstype); | |
330 | saved_errno = errno; | |
331 | ||
332 | ust_after_setns(); | |
333 | ||
334 | errno = saved_errno; | |
335 | return retval; | |
336 | } | |
337 | ||
338 | int unshare(int flags) | |
339 | { | |
340 | static int (*plibc_func)(int flags) = NULL; | |
341 | int retval; | |
342 | int saved_errno; | |
343 | ||
344 | if (plibc_func == NULL) { | |
345 | plibc_func = dlsym(RTLD_NEXT, "unshare"); | |
346 | if (plibc_func == NULL) { | |
347 | fprintf(stderr, "libustfork: unable to find \"unshare\" symbol\n"); | |
348 | errno = ENOSYS; | |
349 | return -1; | |
350 | } | |
351 | } | |
352 | ||
353 | /* Do the real setns */ | |
354 | retval = plibc_func(flags); | |
355 | saved_errno = errno; | |
356 | ||
357 | ust_after_unshare(); | |
358 | ||
359 | errno = saved_errno; | |
360 | return retval; | |
361 | } | |
362 | ||
fca2f191 MJ |
363 | int setresuid(uid_t ruid, uid_t euid, uid_t suid) |
364 | { | |
365 | static int (*plibc_func)(uid_t ruid, uid_t euid, uid_t suid) = NULL; | |
366 | int retval; | |
367 | int saved_errno; | |
368 | ||
369 | if (plibc_func == NULL) { | |
370 | plibc_func = dlsym(RTLD_NEXT, "setresuid"); | |
371 | if (plibc_func == NULL) { | |
372 | fprintf(stderr, "libustfork: unable to find \"setresuid\" symbol\n"); | |
373 | errno = ENOSYS; | |
374 | return -1; | |
375 | } | |
376 | } | |
377 | ||
378 | /* Do the real setresuid */ | |
379 | retval = plibc_func(ruid, euid, suid); | |
380 | saved_errno = errno; | |
381 | ||
382 | ust_after_setresuid(); | |
383 | ||
384 | errno = saved_errno; | |
385 | return retval; | |
386 | } | |
387 | ||
388 | int setresgid(gid_t rgid, gid_t egid, gid_t sgid) | |
389 | { | |
390 | static int (*plibc_func)(gid_t rgid, gid_t egid, gid_t sgid) = NULL; | |
391 | int retval; | |
392 | int saved_errno; | |
393 | ||
394 | if (plibc_func == NULL) { | |
395 | plibc_func = dlsym(RTLD_NEXT, "setresgid"); | |
396 | if (plibc_func == NULL) { | |
397 | fprintf(stderr, "libustfork: unable to find \"setresgid\" symbol\n"); | |
398 | errno = ENOSYS; | |
399 | return -1; | |
400 | } | |
401 | } | |
402 | ||
403 | /* Do the real setresgid */ | |
404 | retval = plibc_func(rgid, egid, sgid); | |
405 | saved_errno = errno; | |
406 | ||
407 | ust_after_setresgid(); | |
408 | ||
409 | errno = saved_errno; | |
410 | return retval; | |
411 | } | |
412 | ||
939c89cb MD |
413 | #elif defined (__FreeBSD__) |
414 | ||
415 | pid_t rfork(int flags) | |
416 | { | |
417 | static pid_t (*plibc_func)(void) = NULL; | |
418 | sigset_t sigset; | |
419 | pid_t retval; | |
111902ab | 420 | int saved_errno; |
939c89cb MD |
421 | |
422 | if (plibc_func == NULL) { | |
423 | plibc_func = dlsym(RTLD_NEXT, "rfork"); | |
424 | if (plibc_func == NULL) { | |
425 | fprintf(stderr, "libustfork: unable to find \"rfork\" symbol\n"); | |
3678c8aa | 426 | errno = ENOSYS; |
939c89cb MD |
427 | return -1; |
428 | } | |
429 | } | |
430 | ||
431 | ust_before_fork(&sigset); | |
432 | /* Do the real rfork */ | |
433 | retval = plibc_func(); | |
111902ab | 434 | saved_errno = errno; |
939c89cb MD |
435 | if (retval == 0) { |
436 | /* child */ | |
437 | ust_after_fork_child(&sigset); | |
438 | } else { | |
439 | ust_after_fork_parent(&sigset); | |
440 | } | |
111902ab | 441 | errno = saved_errno; |
939c89cb MD |
442 | return retval; |
443 | } | |
444 | ||
445 | /* | |
446 | * On BSD, no need to override vfork, because it runs in the context of | |
447 | * the parent, with parent waiting until execve or exit is executed in | |
448 | * the child. | |
449 | */ | |
450 | ||
451 | #else | |
452 | #warning "Unknown OS. You might want to ensure that fork/clone/vfork/fork handling is complete." | |
453 | #endif |