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