xref: /freebsd/sys/compat/linux/linux_signal.c (revision 7660b554bc59a07be0431c17e0e33815818baa69) 
1 /*-
2  * Copyright (c) 1994-1995 S�ren Schmidt
3  * All rights reserved.
4  *
5  * Redistribution and use in source and binary forms, with or without
6  * modification, are permitted provided that the following conditions
7  * are met:
8  * 1. Redistributions of source code must retain the above copyright
9  *    notice, this list of conditions and the following disclaimer
10  *    in this position and unchanged.
11  * 2. Redistributions in binary form must reproduce the above copyright
12  *    notice, this list of conditions and the following disclaimer in the
13  *    documentation and/or other materials provided with the distribution.
14  * 3. The name of the author may not be used to endorse or promote products
15  *    derived from this software without specific prior written permission
16  *
17  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
18  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
19  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
20  * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
21  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
22  * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
23  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
24  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
25  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
26  * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
27  */
28 
29 #include <sys/cdefs.h>
30 __FBSDID("$FreeBSD$");
31 
32 #include <sys/param.h>
33 #include <sys/systm.h>
34 #include <sys/lock.h>
35 #include <sys/mutex.h>
36 #include <sys/proc.h>
37 #include <sys/signalvar.h>
38 #include <sys/syscallsubr.h>
39 #include <sys/sysproto.h>
40 
41 #include <machine/../linux/linux.h>
42 #include <machine/../linux/linux_proto.h>
43 #include <compat/linux/linux_signal.h>
44 #include <compat/linux/linux_util.h>
45 
46 void
47 linux_to_bsd_sigset(l_sigset_t *lss, sigset_t *bss)
48 {
49 	int b, l;
50 
51 	SIGEMPTYSET(*bss);
52 	bss->__bits[0] = lss->__bits[0] & ~((1U << LINUX_SIGTBLSZ) - 1);
53 	bss->__bits[1] = lss->__bits[1];
54 	for (l = 1; l <= LINUX_SIGTBLSZ; l++) {
55 		if (LINUX_SIGISMEMBER(*lss, l)) {
56 #ifdef __alpha__
57 			b = _SIG_IDX(l);
58 #else
59 			b = linux_to_bsd_signal[_SIG_IDX(l)];
60 #endif
61 			if (b)
62 				SIGADDSET(*bss, b);
63 		}
64 	}
65 }
66 
67 void
68 bsd_to_linux_sigset(sigset_t *bss, l_sigset_t *lss)
69 {
70 	int b, l;
71 
72 	LINUX_SIGEMPTYSET(*lss);
73 	lss->__bits[0] = bss->__bits[0] & ~((1U << LINUX_SIGTBLSZ) - 1);
74 	lss->__bits[1] = bss->__bits[1];
75 	for (b = 1; b <= LINUX_SIGTBLSZ; b++) {
76 		if (SIGISMEMBER(*bss, b)) {
77 #if __alpha__
78 			l = _SIG_IDX(b);
79 #else
80 			l = bsd_to_linux_signal[_SIG_IDX(b)];
81 #endif
82 			if (l)
83 				LINUX_SIGADDSET(*lss, l);
84 		}
85 	}
86 }
87 
88 static void
89 linux_to_bsd_sigaction(l_sigaction_t *lsa, struct sigaction *bsa)
90 {
91 
92 	linux_to_bsd_sigset(&lsa->lsa_mask, &bsa->sa_mask);
93 	bsa->sa_handler = lsa->lsa_handler;
94 	bsa->sa_flags = 0;
95 	if (lsa->lsa_flags & LINUX_SA_NOCLDSTOP)
96 		bsa->sa_flags |= SA_NOCLDSTOP;
97 	if (lsa->lsa_flags & LINUX_SA_NOCLDWAIT)
98 		bsa->sa_flags |= SA_NOCLDWAIT;
99 	if (lsa->lsa_flags & LINUX_SA_SIGINFO)
100 		bsa->sa_flags |= SA_SIGINFO;
101 	if (lsa->lsa_flags & LINUX_SA_ONSTACK)
102 		bsa->sa_flags |= SA_ONSTACK;
103 	if (lsa->lsa_flags & LINUX_SA_RESTART)
104 		bsa->sa_flags |= SA_RESTART;
105 	if (lsa->lsa_flags & LINUX_SA_ONESHOT)
106 		bsa->sa_flags |= SA_RESETHAND;
107 	if (lsa->lsa_flags & LINUX_SA_NOMASK)
108 		bsa->sa_flags |= SA_NODEFER;
109 }
110 
111 static void
112 bsd_to_linux_sigaction(struct sigaction *bsa, l_sigaction_t *lsa)
113 {
114 
115 	bsd_to_linux_sigset(&bsa->sa_mask, &lsa->lsa_mask);
116 	lsa->lsa_handler = bsa->sa_handler;
117 	lsa->lsa_restorer = NULL;	/* unsupported */
118 	lsa->lsa_flags = 0;
119 	if (bsa->sa_flags & SA_NOCLDSTOP)
120 		lsa->lsa_flags |= LINUX_SA_NOCLDSTOP;
121 	if (bsa->sa_flags & SA_NOCLDWAIT)
122 		lsa->lsa_flags |= LINUX_SA_NOCLDWAIT;
123 	if (bsa->sa_flags & SA_SIGINFO)
124 		lsa->lsa_flags |= LINUX_SA_SIGINFO;
125 	if (bsa->sa_flags & SA_ONSTACK)
126 		lsa->lsa_flags |= LINUX_SA_ONSTACK;
127 	if (bsa->sa_flags & SA_RESTART)
128 		lsa->lsa_flags |= LINUX_SA_RESTART;
129 	if (bsa->sa_flags & SA_RESETHAND)
130 		lsa->lsa_flags |= LINUX_SA_ONESHOT;
131 	if (bsa->sa_flags & SA_NODEFER)
132 		lsa->lsa_flags |= LINUX_SA_NOMASK;
133 }
134 
135 int
136 linux_do_sigaction(struct thread *td, int linux_sig, l_sigaction_t *linux_nsa,
137 		   l_sigaction_t *linux_osa)
138 {
139 	struct sigaction act, oact, *nsa, *osa;
140 	int error, sig;
141 
142 	if (linux_sig <= 0 || linux_sig > LINUX_NSIG)
143 		return (EINVAL);
144 
145 	osa = (linux_osa != NULL) ? &oact : NULL;
146 	if (linux_nsa != NULL) {
147 		nsa = &act;
148 		linux_to_bsd_sigaction(linux_nsa, nsa);
149 	} else
150 		nsa = NULL;
151 
152 #ifndef __alpha__
153 	if (linux_sig <= LINUX_SIGTBLSZ)
154 		sig = linux_to_bsd_signal[_SIG_IDX(linux_sig)];
155 	else
156 #endif
157 		sig = linux_sig;
158 
159 	error = kern_sigaction(td, sig, nsa, osa, 0);
160 	if (error)
161 		return (error);
162 
163 	if (linux_osa != NULL)
164 		bsd_to_linux_sigaction(osa, linux_osa);
165 
166 	return (0);
167 }
168 
169 
170 #ifndef __alpha__
171 int
172 linux_signal(struct thread *td, struct linux_signal_args *args)
173 {
174 	l_sigaction_t nsa, osa;
175 	int error;
176 
177 #ifdef DEBUG
178 	if (ldebug(signal))
179 		printf(ARGS(signal, "%d, %p"),
180 		    args->sig, (void *)args->handler);
181 #endif
182 
183 	nsa.lsa_handler = args->handler;
184 	nsa.lsa_flags = LINUX_SA_ONESHOT | LINUX_SA_NOMASK;
185 	LINUX_SIGEMPTYSET(nsa.lsa_mask);
186 
187 	error = linux_do_sigaction(td, args->sig, &nsa, &osa);
188 	td->td_retval[0] = (int)osa.lsa_handler;
189 
190 	return (error);
191 }
192 #endif	/*!__alpha__*/
193 
194 int
195 linux_rt_sigaction(struct thread *td, struct linux_rt_sigaction_args *args)
196 {
197 	l_sigaction_t nsa, osa;
198 	int error;
199 
200 #ifdef DEBUG
201 	if (ldebug(rt_sigaction))
202 		printf(ARGS(rt_sigaction, "%ld, %p, %p, %ld"),
203 		    (long)args->sig, (void *)args->act,
204 		    (void *)args->oact, (long)args->sigsetsize);
205 #endif
206 
207 	if (args->sigsetsize != sizeof(l_sigset_t))
208 		return (EINVAL);
209 
210 	if (args->act != NULL) {
211 		error = copyin(args->act, &nsa, sizeof(l_sigaction_t));
212 		if (error)
213 			return (error);
214 	}
215 
216 	error = linux_do_sigaction(td, args->sig,
217 				   args->act ? &nsa : NULL,
218 				   args->oact ? &osa : NULL);
219 
220 	if (args->oact != NULL && !error) {
221 		error = copyout(&osa, args->oact, sizeof(l_sigaction_t));
222 	}
223 
224 	return (error);
225 }
226 
227 static int
228 linux_do_sigprocmask(struct thread *td, int how, l_sigset_t *new,
229 		     l_sigset_t *old)
230 {
231 	sigset_t omask, nmask;
232 	sigset_t *nmaskp;
233 	int error;
234 
235 	td->td_retval[0] = 0;
236 
237 	switch (how) {
238 	case LINUX_SIG_BLOCK:
239 		how = SIG_BLOCK;
240 		break;
241 	case LINUX_SIG_UNBLOCK:
242 		how = SIG_UNBLOCK;
243 		break;
244 	case LINUX_SIG_SETMASK:
245 		how = SIG_SETMASK;
246 		break;
247 	default:
248 		return (EINVAL);
249 	}
250 	if (new != NULL) {
251 		linux_to_bsd_sigset(new, &nmask);
252 		nmaskp = &nmask;
253 	} else
254 		nmaskp = NULL;
255 	error = kern_sigprocmask(td, how, nmaskp, &omask, 0);
256 	if (error == 0 && old != NULL)
257 		bsd_to_linux_sigset(&omask, old);
258 
259 	return (error);
260 }
261 
262 #ifndef __alpha__
263 int
264 linux_sigprocmask(struct thread *td, struct linux_sigprocmask_args *args)
265 {
266 	l_osigset_t mask;
267 	l_sigset_t set, oset;
268 	int error;
269 
270 #ifdef DEBUG
271 	if (ldebug(sigprocmask))
272 		printf(ARGS(sigprocmask, "%d, *, *"), args->how);
273 #endif
274 
275 	if (args->mask != NULL) {
276 		error = copyin(args->mask, &mask, sizeof(l_osigset_t));
277 		if (error)
278 			return (error);
279 		LINUX_SIGEMPTYSET(set);
280 		set.__bits[0] = mask;
281 	}
282 
283 	error = linux_do_sigprocmask(td, args->how,
284 				     args->mask ? &set : NULL,
285 				     args->omask ? &oset : NULL);
286 
287 	if (args->omask != NULL && !error) {
288 		mask = oset.__bits[0];
289 		error = copyout(&mask, args->omask, sizeof(l_osigset_t));
290 	}
291 
292 	return (error);
293 }
294 #endif	/*!__alpha__*/
295 
296 int
297 linux_rt_sigprocmask(struct thread *td, struct linux_rt_sigprocmask_args *args)
298 {
299 	l_sigset_t set, oset;
300 	int error;
301 
302 #ifdef DEBUG
303 	if (ldebug(rt_sigprocmask))
304 		printf(ARGS(rt_sigprocmask, "%d, %p, %p, %ld"),
305 		    args->how, (void *)args->mask,
306 		    (void *)args->omask, (long)args->sigsetsize);
307 #endif
308 
309 	if (args->sigsetsize != sizeof(l_sigset_t))
310 		return EINVAL;
311 
312 	if (args->mask != NULL) {
313 		error = copyin(args->mask, &set, sizeof(l_sigset_t));
314 		if (error)
315 			return (error);
316 	}
317 
318 	error = linux_do_sigprocmask(td, args->how,
319 				     args->mask ? &set : NULL,
320 				     args->omask ? &oset : NULL);
321 
322 	if (args->omask != NULL && !error) {
323 		error = copyout(&oset, args->omask, sizeof(l_sigset_t));
324 	}
325 
326 	return (error);
327 }
328 
329 #ifndef __alpha__
330 int
331 linux_sgetmask(struct thread *td, struct linux_sgetmask_args *args)
332 {
333 	struct proc *p = td->td_proc;
334 	l_sigset_t mask;
335 
336 #ifdef DEBUG
337 	if (ldebug(sgetmask))
338 		printf(ARGS(sgetmask, ""));
339 #endif
340 
341 	PROC_LOCK(p);
342 	bsd_to_linux_sigset(&td->td_sigmask, &mask);
343 	PROC_UNLOCK(p);
344 	td->td_retval[0] = mask.__bits[0];
345 	return (0);
346 }
347 
348 int
349 linux_ssetmask(struct thread *td, struct linux_ssetmask_args *args)
350 {
351 	struct proc *p = td->td_proc;
352 	l_sigset_t lset;
353 	sigset_t bset;
354 
355 #ifdef DEBUG
356 	if (ldebug(ssetmask))
357 		printf(ARGS(ssetmask, "%08lx"), (unsigned long)args->mask);
358 #endif
359 
360 	PROC_LOCK(p);
361 	bsd_to_linux_sigset(&td->td_sigmask, &lset);
362 	td->td_retval[0] = lset.__bits[0];
363 	LINUX_SIGEMPTYSET(lset);
364 	lset.__bits[0] = args->mask;
365 	linux_to_bsd_sigset(&lset, &bset);
366 	td->td_sigmask = bset;
367 	SIG_CANTMASK(td->td_sigmask);
368 	signotify(td);
369 	PROC_UNLOCK(p);
370 	return (0);
371 }
372 
373 /*
374  * MPSAFE
375  */
376 int
377 linux_sigpending(struct thread *td, struct linux_sigpending_args *args)
378 {
379 	struct proc *p = td->td_proc;
380 	sigset_t bset;
381 	l_sigset_t lset;
382 	l_osigset_t mask;
383 
384 #ifdef DEBUG
385 	if (ldebug(sigpending))
386 		printf(ARGS(sigpending, "*"));
387 #endif
388 
389 	PROC_LOCK(p);
390 	bset = p->p_siglist;
391 	SIGSETOR(bset, td->td_siglist);
392 	SIGSETAND(bset, td->td_sigmask);
393 	PROC_UNLOCK(p);
394 	bsd_to_linux_sigset(&bset, &lset);
395 	mask = lset.__bits[0];
396 	return (copyout(&mask, args->mask, sizeof(mask)));
397 }
398 #endif	/*!__alpha__*/
399 
400 int
401 linux_kill(struct thread *td, struct linux_kill_args *args)
402 {
403 	struct kill_args /* {
404 	    int pid;
405 	    int signum;
406 	} */ tmp;
407 
408 #ifdef DEBUG
409 	if (ldebug(kill))
410 		printf(ARGS(kill, "%d, %d"), args->pid, args->signum);
411 #endif
412 
413 	/*
414 	 * Allow signal 0 as a means to check for privileges
415 	 */
416 	if (args->signum < 0 || args->signum > LINUX_NSIG)
417 		return EINVAL;
418 
419 #ifndef __alpha__
420 	if (args->signum > 0 && args->signum <= LINUX_SIGTBLSZ)
421 		tmp.signum = linux_to_bsd_signal[_SIG_IDX(args->signum)];
422 	else
423 #endif
424 		tmp.signum = args->signum;
425 
426 	tmp.pid = args->pid;
427 	return (kill(td, &tmp));
428 }
429