master
1/*-
2 * SPDX-License-Identifier: BSD-3-Clause
3 *
4 * Copyright (c) 1991, 1993
5 * The Regents of the University of California. All rights reserved.
6 *
7 * Redistribution and use in source and binary forms, with or without
8 * modification, are permitted provided that the following conditions
9 * are met:
10 * 1. Redistributions of source code must retain the above copyright
11 * notice, this list of conditions and the following disclaimer.
12 * 2. Redistributions in binary form must reproduce the above copyright
13 * notice, this list of conditions and the following disclaimer in the
14 * documentation and/or other materials provided with the distribution.
15 * 3. Neither the name of the University nor the names of its contributors
16 * may be used to endorse or promote products derived from this software
17 * without specific prior written permission.
18 *
19 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
20 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
21 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
22 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
23 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
24 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
25 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
26 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
27 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
28 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
29 * SUCH DAMAGE.
30 *
31 * @(#)signalvar.h 8.6 (Berkeley) 2/19/95
32 */
33
34#ifndef _SYS_SIGNALVAR_H_
35#define _SYS_SIGNALVAR_H_
36
37#include <sys/queue.h>
38#include <sys/_lock.h>
39#include <sys/_mutex.h>
40#include <sys/signal.h>
41
42/*
43 * Kernel signal definitions and data structures.
44 */
45
46/*
47 * Logical process signal actions and state, needed only within the process
48 * The mapping between sigacts and proc structures is 1:1 except for rfork()
49 * processes masquerading as threads which use one structure for the whole
50 * group. All members are locked by the included mutex. The reference count
51 * and mutex must be last for the bcopy in sigacts_copy() to work.
52 */
53struct sigacts {
54 sig_t ps_sigact[_SIG_MAXSIG]; /* Disposition of signals. */
55 sigset_t ps_catchmask[_SIG_MAXSIG]; /* Signals to be blocked. */
56 sigset_t ps_sigonstack; /* Signals to take on sigstack. */
57 sigset_t ps_sigintr; /* Signals that interrupt syscalls. */
58 sigset_t ps_sigreset; /* Signals that reset when caught. */
59 sigset_t ps_signodefer; /* Signals not masked while handled. */
60 sigset_t ps_siginfo; /* Signals that want SA_SIGINFO args. */
61 sigset_t ps_sigignore; /* Signals being ignored. */
62 sigset_t ps_sigcatch; /* Signals being caught by user. */
63 sigset_t ps_freebsd4; /* Signals using freebsd4 ucontext. */
64 sigset_t ps_osigset; /* Signals using <= 3.x osigset_t. */
65 sigset_t ps_usertramp; /* SunOS compat; libc sigtramp. XXX */
66 int ps_flag;
67 u_int ps_refcnt;
68 struct mtx ps_mtx;
69};
70
71#define PS_NOCLDWAIT 0x0001 /* No zombies if child dies */
72#define PS_NOCLDSTOP 0x0002 /* No SIGCHLD when children stop. */
73#define PS_CLDSIGIGN 0x0004 /* The SIGCHLD handler is SIG_IGN. */
74
75#ifdef _KERNEL
76
77#ifdef COMPAT_43
78typedef struct {
79 struct osigcontext si_sc;
80 int si_signo;
81 int si_code;
82 union sigval si_value;
83} osiginfo_t;
84
85struct osigaction {
86 union {
87 void (*__sa_handler)(int);
88 void (*__sa_sigaction)(int, osiginfo_t *, void *);
89 } __sigaction_u; /* signal handler */
90 osigset_t sa_mask; /* signal mask to apply */
91 int sa_flags; /* see signal options below */
92};
93
94typedef void __osiginfohandler_t(int, osiginfo_t *, void *);
95#endif /* COMPAT_43 */
96
97/* additional signal action values, used only temporarily/internally */
98#define SIG_CATCH ((__sighandler_t *)2)
99/* #define SIG_HOLD ((__sighandler_t *)3) See signal.h */
100
101/*
102 * get signal action for process and signal; currently only for current process
103 */
104#define SIGACTION(p, sig) (p->p_sigacts->ps_sigact[_SIG_IDX(sig)])
105
106#endif /* _KERNEL */
107
108/*
109 * sigset_t manipulation macros.
110 */
111#define SIGADDSET(set, signo) \
112 ((set).__bits[_SIG_WORD(signo)] |= _SIG_BIT(signo))
113
114#define SIGDELSET(set, signo) \
115 ((set).__bits[_SIG_WORD(signo)] &= ~_SIG_BIT(signo))
116
117#define SIGEMPTYSET(set) \
118 do { \
119 int __i; \
120 for (__i = 0; __i < _SIG_WORDS; __i++) \
121 (set).__bits[__i] = 0; \
122 } while (0)
123
124#define SIGFILLSET(set) \
125 do { \
126 int __i; \
127 for (__i = 0; __i < _SIG_WORDS; __i++) \
128 (set).__bits[__i] = ~0U; \
129 } while (0)
130
131#define SIGISMEMBER(set, signo) \
132 ((set).__bits[_SIG_WORD(signo)] & _SIG_BIT(signo))
133
134#define SIGISEMPTY(set) (__sigisempty(&(set)))
135#define SIGNOTEMPTY(set) (!__sigisempty(&(set)))
136
137#define SIGSETEQ(set1, set2) (__sigseteq(&(set1), &(set2)))
138#define SIGSETNEQ(set1, set2) (!__sigseteq(&(set1), &(set2)))
139
140#define SIGSETOR(set1, set2) \
141 do { \
142 int __i; \
143 for (__i = 0; __i < _SIG_WORDS; __i++) \
144 (set1).__bits[__i] |= (set2).__bits[__i]; \
145 } while (0)
146
147#define SIGSETAND(set1, set2) \
148 do { \
149 int __i; \
150 for (__i = 0; __i < _SIG_WORDS; __i++) \
151 (set1).__bits[__i] &= (set2).__bits[__i]; \
152 } while (0)
153
154#define SIGSETNAND(set1, set2) \
155 do { \
156 int __i; \
157 for (__i = 0; __i < _SIG_WORDS; __i++) \
158 (set1).__bits[__i] &= ~(set2).__bits[__i]; \
159 } while (0)
160
161#define SIGSETLO(set1, set2) ((set1).__bits[0] = (set2).__bits[0])
162#define SIGSETOLD(set, oset) ((set).__bits[0] = (oset))
163
164#define SIG_CANTMASK(set) \
165 SIGDELSET(set, SIGKILL), SIGDELSET(set, SIGSTOP)
166
167#define SIG_STOPSIGMASK(set) \
168 SIGDELSET(set, SIGSTOP), SIGDELSET(set, SIGTSTP), \
169 SIGDELSET(set, SIGTTIN), SIGDELSET(set, SIGTTOU)
170
171#define SIG_CONTSIGMASK(set) \
172 SIGDELSET(set, SIGCONT)
173
174#define sigcantmask (sigmask(SIGKILL) | sigmask(SIGSTOP))
175
176#define SIG2OSIG(sig, osig) (osig = (sig).__bits[0])
177#define OSIG2SIG(osig, sig) SIGEMPTYSET(sig); (sig).__bits[0] = osig
178
179static __inline int
180__sigisempty(sigset_t *set)
181{
182 int i;
183
184 for (i = 0; i < _SIG_WORDS; i++) {
185 if (set->__bits[i])
186 return (0);
187 }
188 return (1);
189}
190
191static __inline int
192__sigseteq(sigset_t *set1, sigset_t *set2)
193{
194 int i;
195
196 for (i = 0; i < _SIG_WORDS; i++) {
197 if (set1->__bits[i] != set2->__bits[i])
198 return (0);
199 }
200 return (1);
201}
202
203#ifdef COMPAT_FREEBSD6
204struct osigevent {
205 int sigev_notify; /* Notification type */
206 union {
207 int __sigev_signo; /* Signal number */
208 int __sigev_notify_kqueue;
209 } __sigev_u;
210 union sigval sigev_value; /* Signal value */
211};
212#endif
213
214typedef struct ksiginfo {
215 TAILQ_ENTRY(ksiginfo) ksi_link;
216 siginfo_t ksi_info;
217 int ksi_flags;
218 struct sigqueue *ksi_sigq;
219} ksiginfo_t;
220
221#define ksi_signo ksi_info.si_signo
222#define ksi_errno ksi_info.si_errno
223#define ksi_code ksi_info.si_code
224#define ksi_pid ksi_info.si_pid
225#define ksi_uid ksi_info.si_uid
226#define ksi_status ksi_info.si_status
227#define ksi_addr ksi_info.si_addr
228#define ksi_value ksi_info.si_value
229#define ksi_band ksi_info.si_band
230#define ksi_trapno ksi_info.si_trapno
231#define ksi_overrun ksi_info.si_overrun
232#define ksi_timerid ksi_info.si_timerid
233#define ksi_mqd ksi_info.si_mqd
234
235/* bits for ksi_flags */
236#define KSI_TRAP 0x01 /* Generated by trap. */
237#define KSI_EXT 0x02 /* Externally managed ksi. */
238#define KSI_INS 0x04 /* Directly insert ksi, not the copy */
239#define KSI_SIGQ 0x08 /* Generated by sigqueue, might ret EAGAIN. */
240#define KSI_HEAD 0x10 /* Insert into head, not tail. */
241#define KSI_PTRACE 0x20 /* Generated by ptrace. */
242#define KSI_COPYMASK (KSI_TRAP | KSI_SIGQ | KSI_PTRACE)
243
244#define KSI_ONQ(ksi) ((ksi)->ksi_sigq != NULL)
245
246typedef struct sigqueue {
247 sigset_t sq_signals; /* All pending signals. */
248 sigset_t sq_kill; /* Legacy depth 1 queue. */
249 sigset_t sq_ptrace; /* Depth 1 queue for ptrace(2). */
250 TAILQ_HEAD(, ksiginfo) sq_list;/* Queued signal info. */
251 struct proc *sq_proc;
252 int sq_flags;
253} sigqueue_t;
254
255/* Flags for ksi_flags */
256#define SQ_INIT 0x01
257
258/*
259 * Fast_sigblock
260 */
261#define SIGFASTBLOCK_SETPTR 1
262#define SIGFASTBLOCK_UNBLOCK 2
263#define SIGFASTBLOCK_UNSETPTR 3
264
265#define SIGFASTBLOCK_PEND 0x1
266#define SIGFASTBLOCK_FLAGS 0xf
267#define SIGFASTBLOCK_INC 0x10
268
269#ifndef _KERNEL
270int __sys_sigfastblock(int cmd, void *ptr);
271#endif
272
273#ifdef _KERNEL
274extern bool sigfastblock_fetch_always;
275
276/* Return nonzero if process p has an unmasked pending signal. */
277#define SIGPENDING(td) \
278 ((!SIGISEMPTY((td)->td_siglist) && \
279 !sigsetmasked(&(td)->td_siglist, &(td)->td_sigmask)) || \
280 (!SIGISEMPTY((td)->td_proc->p_siglist) && \
281 !sigsetmasked(&(td)->td_proc->p_siglist, &(td)->td_sigmask)))
282/*
283 * Return the value of the pseudo-expression ((*set & ~*mask) == 0). This
284 * is an optimized version of SIGISEMPTY() on a temporary variable
285 * containing SIGSETNAND(*set, *mask).
286 */
287static __inline bool
288sigsetmasked(sigset_t *set, sigset_t *mask)
289{
290 int i;
291
292 for (i = 0; i < _SIG_WORDS; i++) {
293 if (set->__bits[i] & ~mask->__bits[i])
294 return (false);
295 }
296 return (true);
297}
298
299#define ksiginfo_init(ksi) \
300do { \
301 bzero(ksi, sizeof(ksiginfo_t)); \
302} while (0)
303
304#define ksiginfo_init_trap(ksi) \
305do { \
306 ksiginfo_t *kp = ksi; \
307 bzero(kp, sizeof(ksiginfo_t)); \
308 kp->ksi_flags |= KSI_TRAP; \
309} while (0)
310
311static __inline void
312ksiginfo_copy(ksiginfo_t *src, ksiginfo_t *dst)
313{
314 (dst)->ksi_info = src->ksi_info;
315 (dst)->ksi_flags = (src->ksi_flags & KSI_COPYMASK);
316}
317
318static __inline void
319ksiginfo_set_sigev(ksiginfo_t *dst, struct sigevent *sigev)
320{
321 dst->ksi_signo = sigev->sigev_signo;
322 dst->ksi_value = sigev->sigev_value;
323}
324
325struct pgrp;
326struct proc;
327struct sigio;
328struct thread;
329
330/*
331 * Lock the pointers for a sigio object in the underlying objects of
332 * a file descriptor.
333 */
334#define SIGIO_LOCK() mtx_lock(&sigio_lock)
335#define SIGIO_TRYLOCK() mtx_trylock(&sigio_lock)
336#define SIGIO_UNLOCK() mtx_unlock(&sigio_lock)
337#define SIGIO_LOCKED() mtx_owned(&sigio_lock)
338#define SIGIO_ASSERT_LOCKED() mtx_assert(&sigio_lock, MA_OWNED)
339
340extern struct mtx sigio_lock;
341
342/* Flags for kern_sigprocmask(). */
343#define SIGPROCMASK_OLD 0x0001
344#define SIGPROCMASK_PROC_LOCKED 0x0002
345#define SIGPROCMASK_PS_LOCKED 0x0004
346#define SIGPROCMASK_FASTBLK 0x0008
347
348/*
349 * Modes for sigdeferstop(). Manages behaviour of
350 * thread_suspend_check() in the region delimited by
351 * sigdeferstop()/sigallowstop(). Must be restored to
352 * SIGDEFERSTOP_OFF before returning to userspace.
353 */
354#define SIGDEFERSTOP_NOP 0 /* continue doing whatever is done now */
355#define SIGDEFERSTOP_OFF 1 /* stop ignoring STOPs */
356#define SIGDEFERSTOP_SILENT 2 /* silently ignore STOPs */
357#define SIGDEFERSTOP_EINTR 3 /* ignore STOPs, return EINTR */
358#define SIGDEFERSTOP_ERESTART 4 /* ignore STOPs, return ERESTART */
359
360#define SIGDEFERSTOP_VAL_NCHG (-1) /* placeholder indicating no state change */
361int sigdeferstop_impl(int mode);
362void sigallowstop_impl(int prev);
363
364static inline int
365sigdeferstop(int mode)
366{
367
368 if (__predict_false(mode == SIGDEFERSTOP_NOP))
369 return (SIGDEFERSTOP_VAL_NCHG);
370 return (sigdeferstop_impl(mode));
371}
372
373static inline void
374sigallowstop(int prev)
375{
376
377 if (__predict_true(prev == SIGDEFERSTOP_VAL_NCHG))
378 return;
379 sigallowstop_impl(prev);
380}
381
382int cursig(struct thread *td);
383void execsigs(struct proc *p);
384void killproc(struct proc *p, const char *why);
385ksiginfo_t *ksiginfo_alloc(int mwait);
386void ksiginfo_free(ksiginfo_t *ksi);
387int pksignal(struct proc *p, int sig, ksiginfo_t *ksi);
388void pgsigio(struct sigio **sigiop, int sig, int checkctty);
389void pgsignal(struct pgrp *pgrp, int sig, int checkctty, ksiginfo_t *ksi);
390int postsig(int sig);
391void kern_psignal(struct proc *p, int sig);
392int ptracestop(struct thread *td, int sig, ksiginfo_t *si);
393void sendsig(sig_t catcher, ksiginfo_t *ksi, sigset_t *retmask);
394struct sigacts *sigacts_alloc(void);
395void sigacts_copy(struct sigacts *dest, struct sigacts *src);
396void sigacts_free(struct sigacts *ps);
397struct sigacts *sigacts_hold(struct sigacts *ps);
398int sigacts_shared(struct sigacts *ps);
399int sig_ast_checksusp(struct thread *td);
400int sig_ast_needsigchk(struct thread *td);
401void sig_drop_caught(struct proc *p);
402void sigexit(struct thread *td, int sig) __dead2;
403int sigev_findtd(struct proc *p, struct sigevent *sigev, struct thread **);
404void sigfastblock_clear(struct thread *td);
405void sigfastblock_fetch(struct thread *td);
406int sig_intr(void);
407void siginit(struct proc *p);
408void signotify(struct thread *td);
409void sigqueue_delete(struct sigqueue *queue, int sig);
410void sigqueue_delete_proc(struct proc *p, int sig);
411void sigqueue_flush(struct sigqueue *queue);
412void sigqueue_init(struct sigqueue *queue, struct proc *p);
413void sigqueue_take(ksiginfo_t *ksi);
414void tdksignal(struct thread *td, int sig, ksiginfo_t *ksi);
415int tdsendsignal(struct proc *p, struct thread *td, int sig,
416 ksiginfo_t *ksi);
417void tdsigcleanup(struct thread *td);
418void tdsignal(struct thread *td, int sig);
419void trapsignal(struct thread *td, ksiginfo_t *ksi);
420
421#endif /* _KERNEL */
422
423#endif /* !_SYS_SIGNALVAR_H_ */