1/* $NetBSD: signals.c,v 1.17 2020/05/23 23:42:44 ad Exp $ */ 2 3/*- 4 * Copyright (c) 2010, 2011 Antti Kantee. All Rights Reserved. 5 * 6 * Redistribution and use in source and binary forms, with or without 7 * modification, are permitted provided that the following conditions 8 * are met: 9 * 1. Redistributions of source code must retain the above copyright 10 * notice, this list of conditions and the following disclaimer. 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 * 15 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS 16 * OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED 17 * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE 18 * DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE 19 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 20 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR 21 * SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 22 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 23 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 24 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 25 * SUCH DAMAGE. 26 */ 27 28#include <sys/cdefs.h> 29__KERNEL_RCSID(0, "$NetBSD: signals.c,v 1.17 2020/05/23 23:42:44 ad Exp $"); 30 31#include <sys/param.h> 32#include <sys/atomic.h> 33#include <sys/event.h> 34#include <sys/proc.h> 35#include <sys/signal.h> 36 37#include <rump-sys/kern.h> 38 39#include <rump/rump.h> 40#include <rump/rumpuser.h> 41 42const struct filterops sig_filtops = { 43 .f_attach = (void *)eopnotsupp, 44}; 45 46sigset_t sigcantmask; 47 48static void 49pgrp_apply(struct pgrp *pgrp, int signo, void (*apply)(struct proc *p, int)) 50{ 51 struct proc *p; 52 53 KASSERT(mutex_owned(&proc_lock)); 54 55 LIST_FOREACH(p, &pgrp->pg_members, p_pglist) { 56 mutex_enter(p->p_lock); 57 apply(p, signo); 58 mutex_exit(p->p_lock); 59 } 60} 61 62/* RUMP_SIGMODEL_PANIC */ 63 64static void 65rumpsig_panic(struct proc *p, int signo) 66{ 67 68 switch (signo) { 69 case SIGSYS: 70 case SIGPIPE: 71 break; 72 default: 73 panic("unhandled signal %d", signo); 74 } 75} 76 77/* RUMP_SIGMODEL_IGNORE */ 78 79static void 80rumpsig_ignore(struct proc *p, int signo) 81{ 82 83 return; 84} 85 86/* RUMP_SIGMODEL_RAISE */ 87 88static void 89rumpsig_raise(struct proc *p, int signo) 90{ 91 92 if (RUMP_LOCALPROC_P(p)) { 93 rumpuser_kill(p->p_pid, signo); 94 } else { 95 rump_sysproxy_raise(RUMP_SPVM2CTL(p->p_vmspace), signo); 96 } 97} 98 99static void 100rumpsig_record(struct proc *p, int signo) 101{ 102 103 if (!sigismember(&p->p_sigctx.ps_sigignore, signo)) { 104 sigaddset(&p->p_sigpend.sp_set, signo); 105 } 106} 107 108typedef void (*rumpsig_fn)(struct proc *, int); 109 110static rumpsig_fn rumpsig = rumpsig_raise; 111 112/* 113 * Set signal delivery model. It would be nice if we could 114 * take a functional argument. But then we'd need some 115 * OS independent way to represent a signal number and also 116 * a method for easy processing (parsing is boring). 117 * 118 * Plus, upcalls from the rump kernel into process space except 119 * via rumpuser is a somewhat gray area now. 120 */ 121void 122rump_boot_setsigmodel(enum rump_sigmodel model) 123{ 124 125 switch (model) { 126 case RUMP_SIGMODEL_PANIC: 127 rumpsig = rumpsig_panic; 128 break; 129 case RUMP_SIGMODEL_IGNORE: 130 rumpsig = rumpsig_ignore; 131 break; 132 case RUMP_SIGMODEL_RAISE: 133 rumpsig = rumpsig_raise; 134 break; 135 case RUMP_SIGMODEL_RECORD: 136 rumpsig = rumpsig_record; 137 break; 138 139 /* for compat, though I doubt anyone is using it */ 140 case RUMP_SIGMODEL__HOST_NOTANYMORE: 141 rumpsig = rumpsig_raise; 142 break; 143 } 144} 145 146void 147psignal(struct proc *p, int sig) 148{ 149 150 rumpsig(p, sig); 151} 152 153void 154pgsignal(struct pgrp *pgrp, int sig, int checktty) 155{ 156 157 pgrp_apply(pgrp, sig, rumpsig); 158} 159 160void 161kpsignal(struct proc *p, ksiginfo_t *ksi, void *data) 162{ 163 164 rumpsig(p, ksi->ksi_signo); 165} 166 167void 168kpgsignal(struct pgrp *pgrp, ksiginfo_t *ksi, void *data, int checkctty) 169{ 170 171 pgrp_apply(pgrp, ksi->ksi_signo, rumpsig); 172} 173 174int 175sigispending(struct lwp *l, int signo) 176{ 177 struct proc *p = l->l_proc; 178 sigset_t tset; 179 180 tset = p->p_sigpend.sp_set; 181 182 if (signo == 0) { 183 if (firstsig(&tset) != 0) 184 return EINTR; 185 } else if (sigismember(&tset, signo)) 186 return EINTR; 187 return 0; 188} 189 190void 191sigpending1(struct lwp *l, sigset_t *ss) 192{ 193 struct proc *p = l->l_proc; 194 195 mutex_enter(p->p_lock); 196 *ss = l->l_proc->p_sigpend.sp_set; 197 mutex_exit(p->p_lock); 198} 199 200int 201sigismasked(struct lwp *l, int sig) 202{ 203 204 return sigismember(&l->l_proc->p_sigctx.ps_sigignore, sig); 205} 206 207void 208sigclear(sigpend_t *sp, const sigset_t *mask, ksiginfoq_t *kq) 209{ 210 211 if (mask == NULL) 212 sigemptyset(&sp->sp_set); 213 else 214 sigminusset(mask, &sp->sp_set); 215} 216 217void 218sigclearall(struct proc *p, const sigset_t *mask, ksiginfoq_t *kq) 219{ 220 221 /* don't assert proc lock, hence callable from user context */ 222 sigclear(&p->p_sigpend, mask, kq); 223} 224 225void 226ksiginfo_queue_drain0(ksiginfoq_t *kq) 227{ 228 229 if (!(TAILQ_EMPTY(kq))) 230 panic("how did that get there?"); 231} 232 233int 234sigprocmask1(struct lwp *l, int how, const sigset_t *nss, sigset_t *oss) 235{ 236 sigset_t *mask = &l->l_proc->p_sigctx.ps_sigignore; 237 238 KASSERT(mutex_owned(l->l_proc->p_lock)); 239 240 if (oss) 241 *oss = *mask; 242 243 if (nss) { 244 switch (how) { 245 case SIG_BLOCK: 246 sigplusset(nss, mask); 247 break; 248 case SIG_UNBLOCK: 249 sigminusset(nss, mask); 250 break; 251 case SIG_SETMASK: 252 *mask = *nss; 253 break; 254 default: 255 return EINVAL; 256 } 257 } 258 259 return 0; 260} 261 262void 263siginit(struct proc *p) 264{ 265 266 sigemptyset(&p->p_sigctx.ps_sigignore); 267 sigemptyset(&p->p_sigpend.sp_set); 268} 269 270void 271sigsuspendsetup(struct lwp *l, const sigset_t *ss) 272{ 273 /* XXX: Partial copy of kernel code, remove and use the kernel code. */ 274 struct proc *p = l->l_proc; 275 276 mutex_enter(p->p_lock); 277 l->l_sigrestore = 1; 278 l->l_sigoldmask = l->l_sigmask; 279 l->l_sigmask = *ss; 280 sigminusset(&sigcantmask, &l->l_sigmask); 281 mutex_exit(p->p_lock); 282} 283 284void 285sigsuspendteardown(struct lwp *l) 286{ 287 /* XXX: Copy of kernel code, remove and use the kernel code. */ 288 struct proc *p = l->l_proc; 289 290 mutex_enter(p->p_lock); 291 if (l->l_sigrestore) { 292 l->l_sigrestore = 0; 293 l->l_sigmask = l->l_sigoldmask; 294 } 295 mutex_exit(p->p_lock); 296} 297