xref: /freebsd/sys/compat/linux/linux_signal.c (revision 6de306ecee3831f48debaad1d0b22418faa48e10) 
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/sysproto.h>
34 #include <sys/proc.h>
35 #include <sys/signalvar.h>
36 
37 #include <machine/../linux/linux.h>
38 #include <machine/../linux/linux_proto.h>
39 #include <compat/linux/linux_signal.h>
40 #include <compat/linux/linux_util.h>
41 
42 void
43 linux_to_bsd_sigset(linux_sigset_t *lss, sigset_t *bss)
44 {
45 	int b, l;
46 
47 	SIGEMPTYSET(*bss);
48 	bss->__bits[0] = lss->__bits[0] & ~((1U << LINUX_SIGTBLSZ) - 1);
49 	bss->__bits[1] = lss->__bits[1];
50 	for (l = 1; l <= LINUX_SIGTBLSZ; l++) {
51 		if (LINUX_SIGISMEMBER(*lss, l)) {
52 #ifdef __alpha__
53 			b = _SIG_IDX(l);
54 #else
55 			b = linux_to_bsd_signal[_SIG_IDX(l)];
56 #endif
57 			if (b)
58 				SIGADDSET(*bss, b);
59 		}
60 	}
61 }
62 
63 void
64 bsd_to_linux_sigset(sigset_t *bss, linux_sigset_t *lss)
65 {
66 	int b, l;
67 
68 	LINUX_SIGEMPTYSET(*lss);
69 	lss->__bits[0] = bss->__bits[0] & ~((1U << LINUX_SIGTBLSZ) - 1);
70 	lss->__bits[1] = bss->__bits[1];
71 	for (b = 1; b <= LINUX_SIGTBLSZ; b++) {
72 		if (SIGISMEMBER(*bss, b)) {
73 #if __alpha__
74 			l = _SIG_IDX(b);
75 #else
76 			l = bsd_to_linux_signal[_SIG_IDX(b)];
77 #endif
78 			if (l)
79 				LINUX_SIGADDSET(*lss, l);
80 		}
81 	}
82 }
83 
84 static void
85 linux_to_bsd_sigaction(linux_sigaction_t *lsa, struct sigaction *bsa)
86 {
87 
88 	linux_to_bsd_sigset(&lsa->lsa_mask, &bsa->sa_mask);
89 	bsa->sa_handler = lsa->lsa_handler;
90 	bsa->sa_flags = 0;
91 	if (lsa->lsa_flags & LINUX_SA_NOCLDSTOP)
92 		bsa->sa_flags |= SA_NOCLDSTOP;
93 	if (lsa->lsa_flags & LINUX_SA_NOCLDWAIT)
94 		bsa->sa_flags |= SA_NOCLDWAIT;
95 	if (lsa->lsa_flags & LINUX_SA_SIGINFO)
96 		bsa->sa_flags |= SA_SIGINFO;
97 	if (lsa->lsa_flags & LINUX_SA_ONSTACK)
98 		bsa->sa_flags |= SA_ONSTACK;
99 	if (lsa->lsa_flags & LINUX_SA_RESTART)
100 		bsa->sa_flags |= SA_RESTART;
101 	if (lsa->lsa_flags & LINUX_SA_ONESHOT)
102 		bsa->sa_flags |= SA_RESETHAND;
103 	if (lsa->lsa_flags & LINUX_SA_NOMASK)
104 		bsa->sa_flags |= SA_NODEFER;
105 }
106 
107 static void
108 bsd_to_linux_sigaction(struct sigaction *bsa, linux_sigaction_t *lsa)
109 {
110 
111 	bsd_to_linux_sigset(&bsa->sa_mask, &lsa->lsa_mask);
112 	lsa->lsa_handler = bsa->sa_handler;
113 	lsa->lsa_restorer = NULL;	/* unsupported */
114 	lsa->lsa_flags = 0;
115 	if (bsa->sa_flags & SA_NOCLDSTOP)
116 		lsa->lsa_flags |= LINUX_SA_NOCLDSTOP;
117 	if (bsa->sa_flags & SA_NOCLDWAIT)
118 		lsa->lsa_flags |= LINUX_SA_NOCLDWAIT;
119 	if (bsa->sa_flags & SA_SIGINFO)
120 		lsa->lsa_flags |= LINUX_SA_SIGINFO;
121 	if (bsa->sa_flags & SA_ONSTACK)
122 		lsa->lsa_flags |= LINUX_SA_ONSTACK;
123 	if (bsa->sa_flags & SA_RESTART)
124 		lsa->lsa_flags |= LINUX_SA_RESTART;
125 	if (bsa->sa_flags & SA_RESETHAND)
126 		lsa->lsa_flags |= LINUX_SA_ONESHOT;
127 	if (bsa->sa_flags & SA_NODEFER)
128 		lsa->lsa_flags |= LINUX_SA_NOMASK;
129 }
130 
131 int
132 linux_do_sigaction(struct proc *p, int linux_sig, linux_sigaction_t *linux_nsa,
133 		   linux_sigaction_t *linux_osa)
134 {
135 	struct sigaction *nsa, *osa;
136 	struct sigaction_args sa_args;
137 	int error;
138 	caddr_t sg = stackgap_init();
139 
140 	if (linux_sig <= 0 || linux_sig > LINUX_NSIG)
141 		return (EINVAL);
142 
143 	if (linux_osa != NULL)
144 		osa = stackgap_alloc(&sg, sizeof(struct sigaction));
145 	else
146 		osa = NULL;
147 
148 	if (linux_nsa != NULL) {
149 		nsa = stackgap_alloc(&sg, sizeof(struct sigaction));
150 		linux_to_bsd_sigaction(linux_nsa, nsa);
151 	}
152 	else
153 		nsa = NULL;
154 
155 #ifndef __alpha__
156 	if (linux_sig <= LINUX_SIGTBLSZ)
157 		sa_args.sig = linux_to_bsd_signal[_SIG_IDX(linux_sig)];
158 	else
159 #endif
160 		sa_args.sig = linux_sig;
161 
162 	sa_args.act = nsa;
163 	sa_args.oact = osa;
164 	error = sigaction(p, &sa_args);
165 	if (error)
166 		return (error);
167 
168 	if (linux_osa != NULL)
169 		bsd_to_linux_sigaction(osa, linux_osa);
170 
171 	return (0);
172 }
173 
174 
175 #ifndef __alpha__
176 int
177 linux_signal(struct proc *p, struct linux_signal_args *args)
178 {
179 	linux_sigaction_t nsa, osa;
180 	int error;
181 
182 #ifdef DEBUG
183 	if (ldebug(signal))
184 		printf(ARGS(signal, "%d, %p"),
185 		    args->sig, (void *)args->handler);
186 #endif
187 
188 	nsa.lsa_handler = args->handler;
189 	nsa.lsa_flags = LINUX_SA_ONESHOT | LINUX_SA_NOMASK;
190 	LINUX_SIGEMPTYSET(nsa.lsa_mask);
191 
192 	error = linux_do_sigaction(p, args->sig, &nsa, &osa);
193 	p->p_retval[0] = (int)osa.lsa_handler;
194 
195 	return (error);
196 }
197 #endif	/*!__alpha__*/
198 
199 int
200 linux_rt_sigaction(struct proc *p, struct linux_rt_sigaction_args *args)
201 {
202 	linux_sigaction_t nsa, osa;
203 	int error;
204 
205 #ifdef DEBUG
206 	if (ldebug(rt_sigaction))
207 		printf(ARGS(rt_sigaction, "%ld, %p, %p, %ld"),
208 		    (long)args->sig, (void *)args->act,
209 		    (void *)args->oact, (long)args->sigsetsize);
210 #endif
211 
212 	if (args->sigsetsize != sizeof(linux_sigset_t))
213 		return (EINVAL);
214 
215 	if (args->act != NULL) {
216 		error = copyin(args->act, &nsa, sizeof(linux_sigaction_t));
217 		if (error)
218 			return (error);
219 	}
220 
221 	error = linux_do_sigaction(p, args->sig,
222 				   args->act ? &nsa : NULL,
223 				   args->oact ? &osa : NULL);
224 
225 	if (args->oact != NULL && !error) {
226 		error = copyout(&osa, args->oact, sizeof(linux_sigaction_t));
227 	}
228 
229 	return (error);
230 }
231 
232 static int
233 linux_do_sigprocmask(struct proc *p, int how, linux_sigset_t *new,
234 		     linux_sigset_t *old)
235 {
236 	int error;
237 	sigset_t mask;
238 
239 	error = 0;
240 	p->p_retval[0] = 0;
241 
242 	PROC_LOCK(p);
243 	if (old != NULL)
244 		bsd_to_linux_sigset(&p->p_sigmask, old);
245 
246 	if (new != NULL) {
247 		linux_to_bsd_sigset(new, &mask);
248 
249 		switch (how) {
250 		case LINUX_SIG_BLOCK:
251 			SIGSETOR(p->p_sigmask, mask);
252 			SIG_CANTMASK(p->p_sigmask);
253 			break;
254 		case LINUX_SIG_UNBLOCK:
255 			SIGSETNAND(p->p_sigmask, mask);
256 			break;
257 		case LINUX_SIG_SETMASK:
258 			p->p_sigmask = mask;
259 			SIG_CANTMASK(p->p_sigmask);
260 			break;
261 		default:
262 			error = EINVAL;
263 			break;
264 		}
265 	}
266 	PROC_UNLOCK(p);
267 
268 	return (error);
269 }
270 
271 #ifndef __alpha__
272 int
273 linux_sigprocmask(struct proc *p, struct linux_sigprocmask_args *args)
274 {
275 	linux_osigset_t mask;
276 	linux_sigset_t set, oset;
277 	int error;
278 
279 #ifdef DEBUG
280 	if (ldebug(sigprocmask))
281 		printf(ARGS(sigprocmask, "%d, *, *"), args->how);
282 #endif
283 
284 	if (args->mask != NULL) {
285 		error = copyin(args->mask, &mask, sizeof(linux_osigset_t));
286 		if (error)
287 			return (error);
288 		LINUX_SIGEMPTYSET(set);
289 		set.__bits[0] = mask;
290 	}
291 
292 	error = linux_do_sigprocmask(p, args->how,
293 				     args->mask ? &set : NULL,
294 				     args->omask ? &oset : NULL);
295 
296 	if (args->omask != NULL && !error) {
297 		mask = oset.__bits[0];
298 		error = copyout(&mask, args->omask, sizeof(linux_osigset_t));
299 	}
300 
301 	return (error);
302 }
303 #endif	/*!__alpha__*/
304 
305 int
306 linux_rt_sigprocmask(struct proc *p, struct linux_rt_sigprocmask_args *args)
307 {
308 	linux_sigset_t set, oset;
309 	int error;
310 
311 #ifdef DEBUG
312 	if (ldebug(rt_sigprocmask))
313 		printf(ARGS(rt_sigprocmask, "%d, %p, %p, %ld"),
314 		    args->how, (void *)args->mask,
315 		    (void *)args->omask, (long)args->sigsetsize);
316 #endif
317 
318 	if (args->sigsetsize != sizeof(linux_sigset_t))
319 		return EINVAL;
320 
321 	if (args->mask != NULL) {
322 		error = copyin(args->mask, &set, sizeof(linux_sigset_t));
323 		if (error)
324 			return (error);
325 	}
326 
327 	error = linux_do_sigprocmask(p, args->how,
328 				     args->mask ? &set : NULL,
329 				     args->omask ? &oset : NULL);
330 
331 	if (args->omask != NULL && !error) {
332 		error = copyout(&oset, args->omask, sizeof(linux_sigset_t));
333 	}
334 
335 	return (error);
336 }
337 
338 #ifndef __alpha__
339 int
340 linux_siggetmask(struct proc *p, struct linux_siggetmask_args *args)
341 {
342 	linux_sigset_t mask;
343 
344 #ifdef DEBUG
345 	if (ldebug(siggetmask))
346 		printf(ARGS(siggetmask, ""));
347 #endif
348 
349 	PROC_LOCK(p);
350 	bsd_to_linux_sigset(&p->p_sigmask, &mask);
351 	PROC_UNLOCK(p);
352 	p->p_retval[0] = mask.__bits[0];
353 	return (0);
354 }
355 
356 int
357 linux_sigsetmask(struct proc *p, struct linux_sigsetmask_args *args)
358 {
359 	linux_sigset_t lset;
360 	sigset_t bset;
361 
362 #ifdef DEBUG
363 	if (ldebug(sigsetmask))
364 		printf(ARGS(sigsetmask, "%08lx"), (unsigned long)args->mask);
365 #endif
366 
367 	PROC_LOCK(p);
368 	bsd_to_linux_sigset(&p->p_sigmask, &lset);
369 	p->p_retval[0] = lset.__bits[0];
370 	LINUX_SIGEMPTYSET(lset);
371 	lset.__bits[0] = args->mask;
372 	linux_to_bsd_sigset(&lset, &bset);
373 	p->p_sigmask = bset;
374 	SIG_CANTMASK(p->p_sigmask);
375 	PROC_UNLOCK(p);
376 	return (0);
377 }
378 
379 int
380 linux_sigpending(struct proc *p, struct linux_sigpending_args *args)
381 {
382 	sigset_t bset;
383 	linux_sigset_t lset;
384 	linux_osigset_t mask;
385 
386 #ifdef DEBUG
387 	if (ldebug(sigpending))
388 		printf(ARGS(sigpending, "*"));
389 #endif
390 
391 	PROC_LOCK(p);
392 	bset = p->p_siglist;
393 	SIGSETAND(bset, p->p_sigmask);
394 	bsd_to_linux_sigset(&bset, &lset);
395 	PROC_UNLOCK(p);
396 	mask = lset.__bits[0];
397 	return (copyout(&mask, args->mask, sizeof(mask)));
398 }
399 #endif	/*!__alpha__*/
400 
401 int
402 linux_kill(struct proc *p, struct linux_kill_args *args)
403 {
404 	struct kill_args /* {
405 	    int pid;
406 	    int signum;
407 	} */ tmp;
408 
409 #ifdef DEBUG
410 	if (ldebug(kill))
411 		printf(ARGS(kill, "%d, %d"), args->pid, args->signum);
412 #endif
413 
414 	/*
415 	 * Allow signal 0 as a means to check for privileges
416 	 */
417 	if (args->signum < 0 || args->signum > LINUX_NSIG)
418 		return EINVAL;
419 
420 #ifndef __alpha__
421 	if (args->signum > 0 && args->signum <= LINUX_SIGTBLSZ)
422 		tmp.signum = linux_to_bsd_signal[_SIG_IDX(args->signum)];
423 	else
424 #endif
425 		tmp.signum = args->signum;
426 
427 	tmp.pid = args->pid;
428 	return (kill(p, &tmp));
429 }
430