1 /*
2 * CDDL HEADER START
3 *
4 * The contents of this file are subject to the terms of the
5 * Common Development and Distribution License (the "License").
6 * You may not use this file except in compliance with the License.
7 *
8 * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
9 * or http://www.opensolaris.org/os/licensing.
10 * See the License for the specific language governing permissions
11 * and limitations under the License.
12 *
13 * When distributing Covered Code, include this CDDL HEADER in each
14 * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
15 * If applicable, add the following below this CDDL HEADER, with the
16 * fields enclosed by brackets "[]" replaced with your own identifying
17 * information: Portions Copyright [yyyy] [name of copyright owner]
18 *
19 * CDDL HEADER END
20 */
21 /*
22 * Copyright 2009 Sun Microsystems, Inc. All rights reserved.
23 * Use is subject to license terms.
24 */
25
26 /* Copyright (c) 1983, 1984, 1985, 1986, 1987, 1988, 1989 AT&T */
27 /* All Rights Reserved */
28
29 /*
30 * Portions of this source code were derived from Berkeley 4.3 BSD
31 * under license from the Regents of the University of California.
32 */
33
34 /*
35 * 4.3BSD signal compatibility functions
36 *
37 * the implementation interprets signal masks equal to -1 as "all of the
38 * signals in the signal set", thereby allowing signals with numbers
39 * above 32 to be blocked when referenced in code such as:
40 *
41 * for (i = 0; i < NSIG; i++)
42 * mask |= sigmask(i)
43 */
44
45 #include <sys/types.h>
46 #include <ucontext.h>
47 #include <signal.h>
48 #include <errno.h>
49
50 #undef BUS_OBJERR /* namespace conflict */
51 #include <sys/siginfo.h>
52 #include "libc.h"
53
54 #pragma weak sigvechandler = _sigvechandler
55 #pragma weak sigsetmask = _sigsetmask
56 #pragma weak sigblock = _sigblock
57 #pragma weak sigpause = usigpause
58 #pragma weak sigvec = _sigvec
59 #pragma weak sigstack = _sigstack
60 #pragma weak signal = usignal
61 #pragma weak siginterrupt = _siginterrupt
62
63 #define set2mask(setp) ((setp)->__sigbits[0])
64 #define mask2set(mask, setp) \
65 ((mask) == -1 ? sigfillset(setp) : \
66 (sigemptyset(setp), (((setp)->__sigbits[0]) = (int)(mask))))
67
68 void (*_siguhandler[NSIG])() = { 0 };
69
70 /* forward declarations */
71 int ucbsigsetmask(int);
72 int ucbsigblock(int);
73 int ucbsigvec(int, struct sigvec *, struct sigvec *);
74 int ucbsigpause(int);
75 int ucbsiginterrupt(int, int);
76
77 /*
78 * sigvechandler is the real signal handler installed for all
79 * signals handled in the 4.3BSD compatibility interface - it translates
80 * SVR4 signal hander arguments into 4.3BSD signal handler arguments
81 * and then calls the real handler
82 */
83
84 static void ucbsigvechandler();
85 void
_sigvechandler(int sig,siginfo_t * sip,ucontext_t * ucp)86 _sigvechandler(int sig, siginfo_t *sip, ucontext_t *ucp)
87 {
88
89 ucbsigvechandler(sig, sip, ucp);
90 }
91
92 static void
ucbsigvechandler(int sig,siginfo_t * sip,ucontext_t * ucp)93 ucbsigvechandler(int sig, siginfo_t *sip, ucontext_t *ucp)
94 {
95 struct sigcontext sc;
96 int code;
97 char *addr;
98 int i, j;
99 int gwinswitch = 0;
100
101 sc.sc_onstack = ((ucp->uc_stack.ss_flags & SS_ONSTACK) != 0);
102 sc.sc_mask = set2mask(&ucp->uc_sigmask);
103
104 #if defined(__amd64)
105 sc.sc_sp = (long)ucp->uc_mcontext.gregs[REG_RSP];
106 sc.sc_pc = (long)ucp->uc_mcontext.gregs[REG_RIP];
107 sc.sc_ps = (long)ucp->uc_mcontext.gregs[REG_RFL];
108 sc.sc_r0 = (long)ucp->uc_mcontext.gregs[REG_RAX];
109 sc.sc_r1 = (long)ucp->uc_mcontext.gregs[REG_RDX];
110 #else
111 sc.sc_sp = (int)ucp->uc_mcontext.gregs[UESP];
112 sc.sc_pc = (int)ucp->uc_mcontext.gregs[EIP];
113 sc.sc_ps = (int)ucp->uc_mcontext.gregs[EFL];
114 sc.sc_r0 = (int)ucp->uc_mcontext.gregs[EAX];
115 sc.sc_r1 = (int)ucp->uc_mcontext.gregs[EDX];
116 #endif
117
118 /*
119 * Translate signal codes from new to old.
120 * /usr/include/sys/siginfo.h contains new codes.
121 * /usr/ucbinclude/sys/signal.h contains old codes.
122 */
123 code = 0;
124 addr = SIG_NOADDR;
125 if (sip != NULL && SI_FROMKERNEL(sip)) {
126 addr = sip->si_addr;
127
128 switch (sig) {
129 case SIGILL:
130 case SIGFPE:
131 code = ILL_ILLINSTR_FAULT;
132 break;
133
134 case SIGBUS:
135 switch (sip->si_code) {
136 case BUS_ADRALN:
137 code = BUS_ALIGN;
138 break;
139 case BUS_ADRERR:
140 code = BUS_HWERR;
141 break;
142 default: /* BUS_OBJERR */
143 code = FC_MAKE_ERR(sip->si_errno);
144 break;
145 }
146 break;
147
148 case SIGSEGV:
149 switch (sip->si_code) {
150 case SEGV_MAPERR:
151 code = SEGV_NOMAP;
152 break;
153 case SEGV_ACCERR:
154 code = SEGV_PROT;
155 break;
156 default:
157 code = FC_MAKE_ERR(sip->si_errno);
158 break;
159 }
160 break;
161
162 default:
163 addr = SIG_NOADDR;
164 break;
165 }
166 }
167
168 (*_siguhandler[sig])(sig, code, &sc, addr);
169
170 if (sc.sc_onstack)
171 ucp->uc_stack.ss_flags |= SS_ONSTACK;
172 else
173 ucp->uc_stack.ss_flags &= ~SS_ONSTACK;
174 mask2set(sc.sc_mask, &ucp->uc_sigmask);
175
176 #if defined(__amd64)
177 ucp->uc_mcontext.gregs[REG_RSP] = (long)sc.sc_sp;
178 ucp->uc_mcontext.gregs[REG_RIP] = (long)sc.sc_pc;
179 ucp->uc_mcontext.gregs[REG_RFL] = (long)sc.sc_ps;
180 ucp->uc_mcontext.gregs[REG_RAX] = (long)sc.sc_r0;
181 ucp->uc_mcontext.gregs[REG_RDX] = (long)sc.sc_r1;
182 #else
183 ucp->uc_mcontext.gregs[UESP] = (int)sc.sc_sp;
184 ucp->uc_mcontext.gregs[EIP] = (int)sc.sc_pc;
185 ucp->uc_mcontext.gregs[EFL] = (int)sc.sc_ps;
186 ucp->uc_mcontext.gregs[EAX] = (int)sc.sc_r0;
187 ucp->uc_mcontext.gregs[EDX] = (int)sc.sc_r1;
188 #endif
189
190 setcontext(ucp);
191 }
192
193 int
_sigsetmask(int mask)194 _sigsetmask(int mask)
195 {
196 return (ucbsigsetmask(mask));
197 }
198
199 int
ucbsigsetmask(int mask)200 ucbsigsetmask(int mask)
201 {
202 sigset_t oset;
203 sigset_t nset;
204
205 (void) sigprocmask(0, (sigset_t *)0, &nset);
206 mask2set(mask, &nset);
207 (void) sigprocmask(SIG_SETMASK, &nset, &oset);
208 return (set2mask(&oset));
209 }
210
211 int
_sigblock(int mask)212 _sigblock(int mask)
213 {
214 return (ucbsigblock(mask));
215 }
216
217 int
ucbsigblock(int mask)218 ucbsigblock(int mask)
219 {
220 sigset_t oset;
221 sigset_t nset;
222
223 (void) sigprocmask(0, (sigset_t *)0, &nset);
224 mask2set(mask, &nset);
225 (void) sigprocmask(SIG_BLOCK, &nset, &oset);
226 return (set2mask(&oset));
227 }
228
229 int
usigpause(int mask)230 usigpause(int mask)
231 {
232 return (ucbsigpause(mask));
233 }
234
235 int
ucbsigpause(int mask)236 ucbsigpause(int mask)
237 {
238 sigset_t set, oset;
239 int ret;
240
241 (void) sigprocmask(0, (sigset_t *)0, &set);
242 oset = set;
243 mask2set(mask, &set);
244 ret = sigsuspend(&set);
245 (void) sigprocmask(SIG_SETMASK, &oset, (sigset_t *)0);
246 return (ret);
247 }
248
249 int
_sigvec(int sig,struct sigvec * nvec,struct sigvec * ovec)250 _sigvec(int sig, struct sigvec *nvec, struct sigvec *ovec)
251 {
252 return (ucbsigvec(sig, nvec, ovec));
253 }
254
255 int
ucbsigvec(int sig,struct sigvec * nvec,struct sigvec * ovec)256 ucbsigvec(int sig, struct sigvec *nvec, struct sigvec *ovec)
257 {
258 struct sigaction nact;
259 struct sigaction oact;
260 struct sigaction *nactp;
261 void (*ohandler)(), (*nhandler)();
262
263 if (sig <= 0 || sig >= NSIG) {
264 errno = EINVAL;
265 return (-1);
266 }
267
268 if ((intptr_t)ovec == -1 || (intptr_t)nvec == -1) {
269 errno = EFAULT;
270 return (-1);
271 }
272
273 ohandler = _siguhandler[sig];
274
275 if (nvec) {
276 _sigaction(sig, (struct sigaction *)0, &nact);
277 nhandler = nvec->sv_handler;
278 /*
279 * To be compatible with the behavior of SunOS 4.x:
280 * If the new signal handler is SIG_IGN or SIG_DFL,
281 * do not change the signal's entry in the handler array.
282 * This allows a child of vfork(2) to set signal handlers
283 * to SIG_IGN or SIG_DFL without affecting the parent.
284 */
285 if (nhandler != SIG_DFL && nhandler != SIG_IGN) {
286 _siguhandler[sig] = nhandler;
287 nact.sa_handler = (void (*)())ucbsigvechandler;
288 } else {
289 nact.sa_handler = nhandler;
290 }
291 mask2set(nvec->sv_mask, &nact.sa_mask);
292 if (sig == SIGKILL || sig == SIGSTOP)
293 nact.sa_handler = SIG_DFL;
294 nact.sa_flags = SA_SIGINFO;
295 if (!(nvec->sv_flags & SV_INTERRUPT))
296 nact.sa_flags |= SA_RESTART;
297 if (nvec->sv_flags & SV_RESETHAND)
298 nact.sa_flags |= SA_RESETHAND;
299 if (nvec->sv_flags & SV_ONSTACK)
300 nact.sa_flags |= SA_ONSTACK;
301 nactp = &nact;
302 } else
303 nactp = (struct sigaction *)0;
304
305 if (_sigaction(sig, nactp, &oact) < 0) {
306 _siguhandler[sig] = ohandler;
307 return (-1);
308 }
309
310 if (ovec) {
311 if (oact.sa_handler == SIG_DFL || oact.sa_handler == SIG_IGN)
312 ovec->sv_handler = oact.sa_handler;
313 else
314 ovec->sv_handler = ohandler;
315 ovec->sv_mask = set2mask(&oact.sa_mask);
316 ovec->sv_flags = 0;
317 if (oact.sa_flags & SA_ONSTACK)
318 ovec->sv_flags |= SV_ONSTACK;
319 if (oact.sa_flags & SA_RESETHAND)
320 ovec->sv_flags |= SV_RESETHAND;
321 if (!(oact.sa_flags & SA_RESTART))
322 ovec->sv_flags |= SV_INTERRUPT;
323 }
324
325 return (0);
326 }
327
328 int
_sigstack(struct sigstack * nss,struct sigstack * oss)329 _sigstack(struct sigstack *nss, struct sigstack *oss)
330 {
331 struct sigaltstack nalt;
332 struct sigaltstack oalt;
333 struct sigaltstack *naltp;
334
335 if (nss) {
336 /*
337 * assumes stack growth is down (like sparc and x86)
338 */
339 nalt.ss_sp = nss->ss_sp - SIGSTKSZ;
340 nalt.ss_size = SIGSTKSZ;
341 nalt.ss_flags = 0;
342 naltp = &nalt;
343 } else
344 naltp = (struct sigaltstack *)0;
345
346 if (sigaltstack(naltp, &oalt) < 0)
347 return (-1);
348
349 if (oss) {
350 /*
351 * assumes stack growth is down (like sparc and x86)
352 */
353 oss->ss_sp = oalt.ss_sp + oalt.ss_size;
354 oss->ss_onstack = ((oalt.ss_flags & SS_ONSTACK) != 0);
355 }
356
357 return (0);
358 }
359
360 void (*
ucbsignal(int s,void (* a)())361 ucbsignal(int s, void (*a)()))()
362 {
363 struct sigvec osv;
364 struct sigvec nsv;
365 static int mask[NSIG];
366 static int flags[NSIG];
367
368 nsv.sv_handler = a;
369 nsv.sv_mask = mask[s];
370 nsv.sv_flags = flags[s];
371 if (ucbsigvec(s, &nsv, &osv) < 0)
372 return (SIG_ERR);
373 if (nsv.sv_mask != osv.sv_mask || nsv.sv_flags != osv.sv_flags) {
374 mask[s] = nsv.sv_mask = osv.sv_mask;
375 flags[s] = nsv.sv_flags =
376 osv.sv_flags & ~(SV_RESETHAND|SV_INTERRUPT);
377 if (ucbsigvec(s, &nsv, (struct sigvec *)0) < 0)
378 return (SIG_ERR);
379 }
380 return (osv.sv_handler);
381 }
382
383 void (*
usignal(int s,void (* a)())384 usignal(int s, void (*a)()))()
385 {
386 return (ucbsignal(s, a));
387 }
388
389 /*
390 * Set signal state to prevent restart of system calls
391 * after an instance of the indicated signal.
392 */
393 int
_siginterrupt(int sig,int flag)394 _siginterrupt(int sig, int flag)
395 {
396 return (ucbsiginterrupt(sig, flag));
397 }
398
399 int
ucbsiginterrupt(int sig,int flag)400 ucbsiginterrupt(int sig, int flag)
401 {
402 struct sigvec sv;
403 int ret;
404
405 if ((ret = ucbsigvec(sig, 0, &sv)) < 0)
406 return (ret);
407 if (flag)
408 sv.sv_flags |= SV_INTERRUPT;
409 else
410 sv.sv_flags &= ~SV_INTERRUPT;
411 return (ucbsigvec(sig, &sv, 0));
412 }
413