xref: /freebsd/sys/compat/linux/linux_signal.c (revision 2cdbd5eec4e32beddb3adcca014dda56debc6f5b) 
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 			b = linux_to_bsd_signal[_SIG_IDX(l)];
53 			if (b)
54 				SIGADDSET(*bss, b);
55 		}
56 	}
57 }
58 
59 static void
60 bsd_to_linux_sigset(sigset_t *bss, linux_sigset_t *lss)
61 {
62 	int b, l;
63 
64 	LINUX_SIGEMPTYSET(*lss);
65 	lss->__bits[0] = bss->__bits[0] & ~((1U << LINUX_SIGTBLSZ) - 1);
66 	lss->__bits[1] = bss->__bits[1];
67 	for (b = 1; b <= LINUX_SIGTBLSZ; b++) {
68 		if (SIGISMEMBER(*bss, b)) {
69 			l = bsd_to_linux_signal[_SIG_IDX(b)];
70 			if (l)
71 				LINUX_SIGADDSET(*lss, l);
72 		}
73 	}
74 }
75 
76 static void
77 linux_to_bsd_sigaction(linux_sigaction_t *lsa, struct sigaction *bsa)
78 {
79 
80 	linux_to_bsd_sigset(&lsa->lsa_mask, &bsa->sa_mask);
81 	bsa->sa_handler = lsa->lsa_handler;
82 	bsa->sa_flags = 0;
83 	if (lsa->lsa_flags & LINUX_SA_NOCLDSTOP)
84 		bsa->sa_flags |= SA_NOCLDSTOP;
85 	if (lsa->lsa_flags & LINUX_SA_NOCLDWAIT)
86 		bsa->sa_flags |= SA_NOCLDWAIT;
87 	if (lsa->lsa_flags & LINUX_SA_SIGINFO)
88 		bsa->sa_flags |= SA_SIGINFO;
89 	if (lsa->lsa_flags & LINUX_SA_ONSTACK)
90 		bsa->sa_flags |= SA_ONSTACK;
91 	if (lsa->lsa_flags & LINUX_SA_RESTART)
92 		bsa->sa_flags |= SA_RESTART;
93 	if (lsa->lsa_flags & LINUX_SA_ONESHOT)
94 		bsa->sa_flags |= SA_RESETHAND;
95 	if (lsa->lsa_flags & LINUX_SA_NOMASK)
96 		bsa->sa_flags |= SA_NODEFER;
97 }
98 
99 static void
100 bsd_to_linux_sigaction(struct sigaction *bsa, linux_sigaction_t *lsa)
101 {
102 
103 	bsd_to_linux_sigset(&bsa->sa_mask, &lsa->lsa_mask);
104 	lsa->lsa_handler = bsa->sa_handler;
105 	lsa->lsa_restorer = NULL;	/* unsupported */
106 	lsa->lsa_flags = 0;
107 	if (bsa->sa_flags & SA_NOCLDSTOP)
108 		lsa->lsa_flags |= LINUX_SA_NOCLDSTOP;
109 	if (bsa->sa_flags & SA_NOCLDWAIT)
110 		lsa->lsa_flags |= LINUX_SA_NOCLDWAIT;
111 	if (bsa->sa_flags & SA_SIGINFO)
112 		lsa->lsa_flags |= LINUX_SA_SIGINFO;
113 	if (bsa->sa_flags & SA_ONSTACK)
114 		lsa->lsa_flags |= LINUX_SA_ONSTACK;
115 	if (bsa->sa_flags & SA_RESTART)
116 		lsa->lsa_flags |= LINUX_SA_RESTART;
117 	if (bsa->sa_flags & SA_RESETHAND)
118 		lsa->lsa_flags |= LINUX_SA_ONESHOT;
119 	if (bsa->sa_flags & SA_NODEFER)
120 		lsa->lsa_flags |= LINUX_SA_NOMASK;
121 }
122 
123 int
124 linux_do_sigaction(struct proc *p, int linux_sig, linux_sigaction_t *linux_nsa,
125 		   linux_sigaction_t *linux_osa)
126 {
127 	struct sigaction *nsa, *osa;
128 	struct sigaction_args sa_args;
129 	int error;
130 	caddr_t sg = stackgap_init();
131 
132 	if (linux_sig <= 0 || linux_sig > LINUX_NSIG)
133 		return (EINVAL);
134 
135 	if (linux_osa != NULL)
136 		osa = stackgap_alloc(&sg, sizeof(struct sigaction));
137 	else
138 		osa = NULL;
139 
140 	if (linux_nsa != NULL) {
141 		nsa = stackgap_alloc(&sg, sizeof(struct sigaction));
142 		linux_to_bsd_sigaction(linux_nsa, nsa);
143 	}
144 	else
145 		nsa = NULL;
146 
147 	if (linux_sig <= LINUX_SIGTBLSZ)
148 		sa_args.sig = linux_to_bsd_signal[_SIG_IDX(linux_sig)];
149 	else
150 		sa_args.sig = linux_sig;
151 
152 	sa_args.act = nsa;
153 	sa_args.oact = osa;
154 	error = sigaction(p, &sa_args);
155 	if (error)
156 		return (error);
157 
158 	if (linux_osa != NULL)
159 		bsd_to_linux_sigaction(osa, linux_osa);
160 
161 	return (0);
162 }
163 
164 int
165 linux_signal(struct proc *p, struct linux_signal_args *args)
166 {
167 	linux_sigaction_t nsa, osa;
168 	int error;
169 
170 #ifdef DEBUG
171 	printf("Linux-emul(%ld): signal(%d, %p)\n",
172 	       (long)p->p_pid, args->sig, (void *)args->handler);
173 #endif
174 
175 	nsa.lsa_handler = args->handler;
176 	nsa.lsa_flags = LINUX_SA_ONESHOT | LINUX_SA_NOMASK;
177 	LINUX_SIGEMPTYSET(nsa.lsa_mask);
178 
179 	error = linux_do_sigaction(p, args->sig, &nsa, &osa);
180 	p->p_retval[0] = (int)osa.lsa_handler;
181 
182 	return (error);
183 }
184 
185 int
186 linux_rt_sigaction(struct proc *p, struct linux_rt_sigaction_args *args)
187 {
188 	linux_sigaction_t nsa, osa;
189 	int error;
190 
191 #ifdef DEBUG
192 	printf("Linux-emul(%ld): rt_sigaction(%d, %p, %p, %d)\n",
193 	       (long)p->p_pid, args->sig, (void *)args->act,
194 	       (void *)args->oact, args->sigsetsize);
195 #endif
196 
197 	if (args->sigsetsize != sizeof(linux_sigset_t))
198 		return (EINVAL);
199 
200 	if (args->act != NULL) {
201 		error = copyin(args->act, &nsa, sizeof(linux_sigaction_t));
202 		if (error)
203 			return (error);
204 	}
205 
206 	error = linux_do_sigaction(p, args->sig,
207 				   args->act ? &nsa : NULL,
208 				   args->oact ? &osa : NULL);
209 
210 	if (args->oact != NULL && !error) {
211 		error = copyout(&osa, args->oact, sizeof(linux_sigaction_t));
212 	}
213 
214 	return (error);
215 }
216 
217 static int
218 linux_do_sigprocmask(struct proc *p, int how, linux_sigset_t *new,
219 		     linux_sigset_t *old)
220 {
221 	int error, s;
222 	sigset_t mask;
223 
224 	error = 0;
225 	p->p_retval[0] = 0;
226 
227 	if (old != NULL)
228 		bsd_to_linux_sigset(&p->p_sigmask, old);
229 
230 	if (new != NULL) {
231 		linux_to_bsd_sigset(new, &mask);
232 
233 		s = splhigh();
234 
235 		switch (how) {
236 		case LINUX_SIG_BLOCK:
237 			SIGSETOR(p->p_sigmask, mask);
238 			SIG_CANTMASK(p->p_sigmask);
239 			break;
240 		case LINUX_SIG_UNBLOCK:
241 			SIGSETNAND(p->p_sigmask, mask);
242 			break;
243 		case LINUX_SIG_SETMASK:
244 			p->p_sigmask = mask;
245 			SIG_CANTMASK(p->p_sigmask);
246 			break;
247 		default:
248 			error = EINVAL;
249 			break;
250 		}
251 
252 		splx(s);
253 	}
254 
255 	return (error);
256 }
257 
258 int
259 linux_sigprocmask(struct proc *p, struct linux_sigprocmask_args *args)
260 {
261 	linux_osigset_t mask;
262 	linux_sigset_t set, oset;
263 	int error;
264 
265 #ifdef DEBUG
266 	printf("Linux-emul(%d): sigprocmask(%d, *, *)\n", p->p_pid, args->how);
267 #endif
268 
269 	if (args->mask != NULL) {
270 		error = copyin(args->mask, &mask, sizeof(linux_osigset_t));
271 		if (error)
272 			return (error);
273 		LINUX_SIGEMPTYSET(set);
274 		set.__bits[0] = mask;
275 	}
276 
277 	error = linux_do_sigprocmask(p, args->how,
278 				     args->mask ? &set : NULL,
279 				     args->omask ? &oset : NULL);
280 
281 	if (args->omask != NULL && !error) {
282 		mask = oset.__bits[0];
283 		error = copyout(&mask, args->omask, sizeof(linux_osigset_t));
284 	}
285 
286 	return (error);
287 }
288 
289 int
290 linux_rt_sigprocmask(struct proc *p, struct linux_rt_sigprocmask_args *args)
291 {
292 	linux_sigset_t set, oset;
293 	int error;
294 
295 #ifdef DEBUG
296 	printf("Linux-emul(%ld): rt_sigprocmask(%d, %p, %p, %d)\n",
297 	       (long)p->p_pid, args->how, (void *)args->mask,
298 	       (void *)args->omask, args->sigsetsize);
299 #endif
300 
301 	if (args->sigsetsize != sizeof(linux_sigset_t))
302 		return EINVAL;
303 
304 	if (args->mask != NULL) {
305 		error = copyin(args->mask, &set, sizeof(linux_sigset_t));
306 		if (error)
307 			return (error);
308 	}
309 
310 	error = linux_do_sigprocmask(p, args->how,
311 				     args->mask ? &set : NULL,
312 				     args->omask ? &oset : NULL);
313 
314 	if (args->omask != NULL && !error) {
315 		error = copyout(&oset, args->omask, sizeof(linux_sigset_t));
316 	}
317 
318 	return (error);
319 }
320 
321 int
322 linux_siggetmask(struct proc *p, struct linux_siggetmask_args *args)
323 {
324 	linux_sigset_t mask;
325 
326 #ifdef DEBUG
327 	printf("Linux-emul(%d): siggetmask()\n", p->p_pid);
328 #endif
329 
330 	bsd_to_linux_sigset(&p->p_sigmask, &mask);
331 	p->p_retval[0] = mask.__bits[0];
332 	return (0);
333 }
334 
335 int
336 linux_sigsetmask(struct proc *p, struct linux_sigsetmask_args *args)
337 {
338 	linux_sigset_t lset;
339 	sigset_t bset;
340 	int s;
341 
342 #ifdef DEBUG
343 	printf("Linux-emul(%ld): sigsetmask(%08lx)\n",
344 	       (long)p->p_pid, (unsigned long)args->mask);
345 #endif
346 
347 	bsd_to_linux_sigset(&p->p_sigmask, &lset);
348 	p->p_retval[0] = lset.__bits[0];
349 	LINUX_SIGEMPTYSET(lset);
350 	lset.__bits[0] = args->mask;
351 	linux_to_bsd_sigset(&lset, &bset);
352 	s = splhigh();
353 	p->p_sigmask = bset;
354 	SIG_CANTMASK(p->p_sigmask);
355 	splx(s);
356 	return (0);
357 }
358 
359 int
360 linux_sigpending(struct proc *p, struct linux_sigpending_args *args)
361 {
362 	sigset_t bset;
363 	linux_sigset_t lset;
364 	linux_osigset_t mask;
365 
366 #ifdef DEBUG
367 	printf("Linux-emul(%d): sigpending(*)\n", p->p_pid);
368 #endif
369 
370 	bset = p->p_siglist;
371 	SIGSETAND(bset, p->p_sigmask);
372 	bsd_to_linux_sigset(&bset, &lset);
373 	mask = lset.__bits[0];
374 	return (copyout(&mask, args->mask, sizeof(mask)));
375 }
376 
377 int
378 linux_kill(struct proc *p, struct linux_kill_args *args)
379 {
380 	struct kill_args /* {
381 	    int pid;
382 	    int signum;
383 	} */ tmp;
384 
385 #ifdef DEBUG
386 	printf("Linux-emul(%d): kill(%d, %d)\n",
387 	       p->p_pid, args->pid, args->signum);
388 #endif
389 
390 	/*
391 	 * Allow signal 0 as a means to check for privileges
392 	 */
393 	if (args->signum < 0 || args->signum > LINUX_NSIG)
394 		return EINVAL;
395 
396 	if (args->signum > 0 && args->signum <= LINUX_SIGTBLSZ)
397 		tmp.signum = linux_to_bsd_signal[_SIG_IDX(args->signum)];
398 	else
399 		tmp.signum = args->signum;
400 
401 	tmp.pid = args->pid;
402 	return (kill(p, &tmp));
403 }
404