xref: /freebsd/sys/compat/linux/linux_signal.c (revision 79065dba2a88baf780767cbb1bb31d4525a08528) 
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 withough 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  * $FreeBSD$
29  */
30 
31 #include <sys/param.h>
32 #include <sys/systm.h>
33 #include <sys/lock.h>
34 #include <sys/mutex.h>
35 #include <sys/proc.h>
36 #include <sys/signalvar.h>
37 #include <sys/sysproto.h>
38 
39 #include <machine/../linux/linux.h>
40 #include <machine/../linux/linux_proto.h>
41 #include <compat/linux/linux_signal.h>
42 #include <compat/linux/linux_util.h>
43 
44 void
45 linux_to_bsd_sigset(l_sigset_t *lss, sigset_t *bss)
46 {
47 	int b, l;
48 
49 	SIGEMPTYSET(*bss);
50 	bss->__bits[0] = lss->__bits[0] & ~((1U << LINUX_SIGTBLSZ) - 1);
51 	bss->__bits[1] = lss->__bits[1];
52 	for (l = 1; l <= LINUX_SIGTBLSZ; l++) {
53 		if (LINUX_SIGISMEMBER(*lss, l)) {
54 #ifdef __alpha__
55 			b = _SIG_IDX(l);
56 #else
57 			b = linux_to_bsd_signal[_SIG_IDX(l)];
58 #endif
59 			if (b)
60 				SIGADDSET(*bss, b);
61 		}
62 	}
63 }
64 
65 void
66 bsd_to_linux_sigset(sigset_t *bss, l_sigset_t *lss)
67 {
68 	int b, l;
69 
70 	LINUX_SIGEMPTYSET(*lss);
71 	lss->__bits[0] = bss->__bits[0] & ~((1U << LINUX_SIGTBLSZ) - 1);
72 	lss->__bits[1] = bss->__bits[1];
73 	for (b = 1; b <= LINUX_SIGTBLSZ; b++) {
74 		if (SIGISMEMBER(*bss, b)) {
75 #if __alpha__
76 			l = _SIG_IDX(b);
77 #else
78 			l = bsd_to_linux_signal[_SIG_IDX(b)];
79 #endif
80 			if (l)
81 				LINUX_SIGADDSET(*lss, l);
82 		}
83 	}
84 }
85 
86 static void
87 linux_to_bsd_sigaction(l_sigaction_t *lsa, struct sigaction *bsa)
88 {
89 
90 	linux_to_bsd_sigset(&lsa->lsa_mask, &bsa->sa_mask);
91 	bsa->sa_handler = lsa->lsa_handler;
92 	bsa->sa_flags = 0;
93 	if (lsa->lsa_flags & LINUX_SA_NOCLDSTOP)
94 		bsa->sa_flags |= SA_NOCLDSTOP;
95 	if (lsa->lsa_flags & LINUX_SA_NOCLDWAIT)
96 		bsa->sa_flags |= SA_NOCLDWAIT;
97 	if (lsa->lsa_flags & LINUX_SA_SIGINFO)
98 		bsa->sa_flags |= SA_SIGINFO;
99 	if (lsa->lsa_flags & LINUX_SA_ONSTACK)
100 		bsa->sa_flags |= SA_ONSTACK;
101 	if (lsa->lsa_flags & LINUX_SA_RESTART)
102 		bsa->sa_flags |= SA_RESTART;
103 	if (lsa->lsa_flags & LINUX_SA_ONESHOT)
104 		bsa->sa_flags |= SA_RESETHAND;
105 	if (lsa->lsa_flags & LINUX_SA_NOMASK)
106 		bsa->sa_flags |= SA_NODEFER;
107 }
108 
109 static void
110 bsd_to_linux_sigaction(struct sigaction *bsa, l_sigaction_t *lsa)
111 {
112 
113 	bsd_to_linux_sigset(&bsa->sa_mask, &lsa->lsa_mask);
114 	lsa->lsa_handler = bsa->sa_handler;
115 	lsa->lsa_restorer = NULL;	/* unsupported */
116 	lsa->lsa_flags = 0;
117 	if (bsa->sa_flags & SA_NOCLDSTOP)
118 		lsa->lsa_flags |= LINUX_SA_NOCLDSTOP;
119 	if (bsa->sa_flags & SA_NOCLDWAIT)
120 		lsa->lsa_flags |= LINUX_SA_NOCLDWAIT;
121 	if (bsa->sa_flags & SA_SIGINFO)
122 		lsa->lsa_flags |= LINUX_SA_SIGINFO;
123 	if (bsa->sa_flags & SA_ONSTACK)
124 		lsa->lsa_flags |= LINUX_SA_ONSTACK;
125 	if (bsa->sa_flags & SA_RESTART)
126 		lsa->lsa_flags |= LINUX_SA_RESTART;
127 	if (bsa->sa_flags & SA_RESETHAND)
128 		lsa->lsa_flags |= LINUX_SA_ONESHOT;
129 	if (bsa->sa_flags & SA_NODEFER)
130 		lsa->lsa_flags |= LINUX_SA_NOMASK;
131 }
132 
133 int
134 linux_do_sigaction(struct thread *td, int linux_sig, l_sigaction_t *linux_nsa,
135 		   l_sigaction_t *linux_osa)
136 {
137 	struct sigaction *nsa, *osa;
138 	struct sigaction_args sa_args;
139 	int error;
140 	caddr_t sg = stackgap_init();
141 
142 	if (linux_sig <= 0 || linux_sig > LINUX_NSIG)
143 		return (EINVAL);
144 
145 	if (linux_osa != NULL)
146 		osa = stackgap_alloc(&sg, sizeof(struct sigaction));
147 	else
148 		osa = NULL;
149 
150 	if (linux_nsa != NULL) {
151 		nsa = stackgap_alloc(&sg, sizeof(struct sigaction));
152 		linux_to_bsd_sigaction(linux_nsa, nsa);
153 	}
154 	else
155 		nsa = NULL;
156 
157 #ifndef __alpha__
158 	if (linux_sig <= LINUX_SIGTBLSZ)
159 		sa_args.sig = linux_to_bsd_signal[_SIG_IDX(linux_sig)];
160 	else
161 #endif
162 		sa_args.sig = linux_sig;
163 
164 	sa_args.act = nsa;
165 	sa_args.oact = osa;
166 	error = sigaction(td, &sa_args);
167 	if (error)
168 		return (error);
169 
170 	if (linux_osa != NULL)
171 		bsd_to_linux_sigaction(osa, linux_osa);
172 
173 	return (0);
174 }
175 
176 
177 #ifndef __alpha__
178 int
179 linux_signal(struct thread *td, struct linux_signal_args *args)
180 {
181 	l_sigaction_t nsa, osa;
182 	int error;
183 
184 #ifdef DEBUG
185 	if (ldebug(signal))
186 		printf(ARGS(signal, "%d, %p"),
187 		    args->sig, (void *)args->handler);
188 #endif
189 
190 	nsa.lsa_handler = args->handler;
191 	nsa.lsa_flags = LINUX_SA_ONESHOT | LINUX_SA_NOMASK;
192 	LINUX_SIGEMPTYSET(nsa.lsa_mask);
193 
194 	error = linux_do_sigaction(td, args->sig, &nsa, &osa);
195 	td->td_retval[0] = (int)osa.lsa_handler;
196 
197 	return (error);
198 }
199 #endif	/*!__alpha__*/
200 
201 int
202 linux_rt_sigaction(struct thread *td, struct linux_rt_sigaction_args *args)
203 {
204 	l_sigaction_t nsa, osa;
205 	int error;
206 
207 #ifdef DEBUG
208 	if (ldebug(rt_sigaction))
209 		printf(ARGS(rt_sigaction, "%ld, %p, %p, %ld"),
210 		    (long)args->sig, (void *)args->act,
211 		    (void *)args->oact, (long)args->sigsetsize);
212 #endif
213 
214 	if (args->sigsetsize != sizeof(l_sigset_t))
215 		return (EINVAL);
216 
217 	if (args->act != NULL) {
218 		error = copyin(args->act, &nsa, sizeof(l_sigaction_t));
219 		if (error)
220 			return (error);
221 	}
222 
223 	error = linux_do_sigaction(td, args->sig,
224 				   args->act ? &nsa : NULL,
225 				   args->oact ? &osa : NULL);
226 
227 	if (args->oact != NULL && !error) {
228 		error = copyout(&osa, args->oact, sizeof(l_sigaction_t));
229 	}
230 
231 	return (error);
232 }
233 
234 static int
235 linux_do_sigprocmask(struct thread *td, int how, l_sigset_t *new,
236 		     l_sigset_t *old)
237 {
238 	int error;
239 	sigset_t mask;
240 	struct proc *p = td->td_proc;
241 
242 	error = 0;
243 	td->td_retval[0] = 0;
244 
245 	PROC_LOCK(p);
246 	if (old != NULL)
247 		bsd_to_linux_sigset(&p->p_sigmask, old);
248 
249 	if (new != NULL) {
250 		linux_to_bsd_sigset(new, &mask);
251 
252 		switch (how) {
253 		case LINUX_SIG_BLOCK:
254 			SIGSETOR(p->p_sigmask, mask);
255 			SIG_CANTMASK(p->p_sigmask);
256 			break;
257 		case LINUX_SIG_UNBLOCK:
258 			SIGSETNAND(p->p_sigmask, mask);
259 			signotify(p);
260 			break;
261 		case LINUX_SIG_SETMASK:
262 			p->p_sigmask = mask;
263 			SIG_CANTMASK(p->p_sigmask);
264 			signotify(p);
265 			break;
266 		default:
267 			error = EINVAL;
268 			break;
269 		}
270 	}
271 	PROC_UNLOCK(p);
272 
273 	return (error);
274 }
275 
276 #ifndef __alpha__
277 int
278 linux_sigprocmask(struct thread *td, struct linux_sigprocmask_args *args)
279 {
280 	l_osigset_t mask;
281 	l_sigset_t set, oset;
282 	int error;
283 
284 #ifdef DEBUG
285 	if (ldebug(sigprocmask))
286 		printf(ARGS(sigprocmask, "%d, *, *"), args->how);
287 #endif
288 
289 	if (args->mask != NULL) {
290 		error = copyin(args->mask, &mask, sizeof(l_osigset_t));
291 		if (error)
292 			return (error);
293 		LINUX_SIGEMPTYSET(set);
294 		set.__bits[0] = mask;
295 	}
296 
297 	error = linux_do_sigprocmask(td, args->how,
298 				     args->mask ? &set : NULL,
299 				     args->omask ? &oset : NULL);
300 
301 	if (args->omask != NULL && !error) {
302 		mask = oset.__bits[0];
303 		error = copyout(&mask, args->omask, sizeof(l_osigset_t));
304 	}
305 
306 	return (error);
307 }
308 #endif	/*!__alpha__*/
309 
310 int
311 linux_rt_sigprocmask(struct thread *td, struct linux_rt_sigprocmask_args *args)
312 {
313 	l_sigset_t set, oset;
314 	int error;
315 
316 #ifdef DEBUG
317 	if (ldebug(rt_sigprocmask))
318 		printf(ARGS(rt_sigprocmask, "%d, %p, %p, %ld"),
319 		    args->how, (void *)args->mask,
320 		    (void *)args->omask, (long)args->sigsetsize);
321 #endif
322 
323 	if (args->sigsetsize != sizeof(l_sigset_t))
324 		return EINVAL;
325 
326 	if (args->mask != NULL) {
327 		error = copyin(args->mask, &set, sizeof(l_sigset_t));
328 		if (error)
329 			return (error);
330 	}
331 
332 	error = linux_do_sigprocmask(td, args->how,
333 				     args->mask ? &set : NULL,
334 				     args->omask ? &oset : NULL);
335 
336 	if (args->omask != NULL && !error) {
337 		error = copyout(&oset, args->omask, sizeof(l_sigset_t));
338 	}
339 
340 	return (error);
341 }
342 
343 #ifndef __alpha__
344 int
345 linux_sgetmask(struct thread *td, struct linux_sgetmask_args *args)
346 {
347 	struct proc *p = td->td_proc;
348 	l_sigset_t mask;
349 
350 #ifdef DEBUG
351 	if (ldebug(sgetmask))
352 		printf(ARGS(sgetmask, ""));
353 #endif
354 
355 	PROC_LOCK(p);
356 	bsd_to_linux_sigset(&p->p_sigmask, &mask);
357 	PROC_UNLOCK(p);
358 	td->td_retval[0] = mask.__bits[0];
359 	return (0);
360 }
361 
362 int
363 linux_ssetmask(struct thread *td, struct linux_ssetmask_args *args)
364 {
365 	struct proc *p = td->td_proc;
366 	l_sigset_t lset;
367 	sigset_t bset;
368 
369 #ifdef DEBUG
370 	if (ldebug(ssetmask))
371 		printf(ARGS(ssetmask, "%08lx"), (unsigned long)args->mask);
372 #endif
373 
374 	PROC_LOCK(p);
375 	bsd_to_linux_sigset(&p->p_sigmask, &lset);
376 	td->td_retval[0] = lset.__bits[0];
377 	LINUX_SIGEMPTYSET(lset);
378 	lset.__bits[0] = args->mask;
379 	linux_to_bsd_sigset(&lset, &bset);
380 	p->p_sigmask = bset;
381 	SIG_CANTMASK(p->p_sigmask);
382 	signotify(p);
383 	PROC_UNLOCK(p);
384 	return (0);
385 }
386 
387 int
388 linux_sigpending(struct thread *td, struct linux_sigpending_args *args)
389 {
390 	struct proc *p = td->td_proc;
391 	sigset_t bset;
392 	l_sigset_t lset;
393 	l_osigset_t mask;
394 
395 #ifdef DEBUG
396 	if (ldebug(sigpending))
397 		printf(ARGS(sigpending, "*"));
398 #endif
399 
400 	PROC_LOCK(p);
401 	bset = p->p_siglist;
402 	SIGSETAND(bset, p->p_sigmask);
403 	bsd_to_linux_sigset(&bset, &lset);
404 	PROC_UNLOCK(p);
405 	mask = lset.__bits[0];
406 	return (copyout(&mask, args->mask, sizeof(mask)));
407 }
408 #endif	/*!__alpha__*/
409 
410 int
411 linux_kill(struct thread *td, struct linux_kill_args *args)
412 {
413 	struct kill_args /* {
414 	    int pid;
415 	    int signum;
416 	} */ tmp;
417 
418 #ifdef DEBUG
419 	if (ldebug(kill))
420 		printf(ARGS(kill, "%d, %d"), args->pid, args->signum);
421 #endif
422 
423 	/*
424 	 * Allow signal 0 as a means to check for privileges
425 	 */
426 	if (args->signum < 0 || args->signum > LINUX_NSIG)
427 		return EINVAL;
428 
429 #ifndef __alpha__
430 	if (args->signum > 0 && args->signum <= LINUX_SIGTBLSZ)
431 		tmp.signum = linux_to_bsd_signal[_SIG_IDX(args->signum)];
432 	else
433 #endif
434 		tmp.signum = args->signum;
435 
436 	tmp.pid = args->pid;
437 	return (kill(td, &tmp));
438 }
439