/*
* CDDL HEADER START
*
* The contents of this file are subject to the terms of the
* Common Development and Distribution License (the "License").
* You may not use this file except in compliance with the License.
*
* You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
* or http://www.opensolaris.org/os/licensing.
* See the License for the specific language governing permissions
* and limitations under the License.
*
* When distributing Covered Code, include this CDDL HEADER in each
* file and include the License file at usr/src/OPENSOLARIS.LICENSE.
* If applicable, add the following below this CDDL HEADER, with the
* fields enclosed by brackets "[]" replaced with your own identifying
* information: Portions Copyright [yyyy] [name of copyright owner]
*
* CDDL HEADER END
*/
/*
* Copyright 2006 Sun Microsystems, Inc. All rights reserved.
* Use is subject to license terms.
*/
/* Copyright (c) 1984, 1986, 1987, 1988, 1989 AT&T */
#include <sys/param.h>
#include <sys/types.h>
#include <sys/sysmacros.h>
#include <sys/systm.h>
#include <sys/errno.h>
#include <sys/proc.h>
#include <sys/procset.h>
#include <sys/fault.h>
#include <sys/signal.h>
#include <sys/siginfo.h>
#include <sys/debug.h>
extern rctl_hndl_t rc_process_sigqueue;
static int
sigqkill(pid_t pid, sigsend_t *sigsend)
{
proc_t *p;
int error;
if ((uint_t)sigsend->sig >= NSIG)
return (EINVAL);
if (pid == -1) {
procset_t set;
setprocset(&set, POP_AND, P_ALL, P_MYID, P_ALL, P_MYID);
error = sigsendset(&set, sigsend);
} else if (pid > 0) {
mutex_enter(&pidlock);
if ((p = prfind(pid)) == NULL || p->p_stat == SIDL)
error = ESRCH;
else {
error = sigsendproc(p, sigsend);
if (error == 0 && sigsend->perm == 0)
error = EPERM;
}
mutex_exit(&pidlock);
} else {
int nfound = 0;
pid_t pgid;
if (pid == 0)
pgid = ttoproc(curthread)->p_pgrp;
else
pgid = -pid;
error = 0;
mutex_enter(&pidlock);
for (p = pgfind(pgid); p && !error; p = p->p_pglink) {
if (p->p_stat != SIDL) {
nfound++;
error = sigsendproc(p, sigsend);
}
}
mutex_exit(&pidlock);
if (nfound == 0)
error = ESRCH;
else if (error == 0 && sigsend->perm == 0)
error = EPERM;
}
return (error);
}
/*
* for implementations that don't require binary compatibility,
* the kill system call may be made into a library call to the
* sigsend system call
*/
int
kill(pid_t pid, int sig)
{
int error;
sigsend_t v;
bzero(&v, sizeof (v));
v.sig = sig;
v.checkperm = 1;
v.sicode = SI_USER;
if ((error = sigqkill(pid, &v)) != 0)
return (set_errno(error));
return (0);
}
/*
* The handling of small unions, like the sigval argument to sigqueue,
* is architecture dependent. We have adopted the convention that the
* value itself is passed in the storage which crosses the kernel
* protection boundary. This procedure will accept a scalar argument,
* and store it in the appropriate value member of the sigsend_t structure.
*/
int
sigqueue(pid_t pid, int sig, /* union sigval */ void *value,
int si_code, int block)
{
int error;
sigsend_t v;
sigqhdr_t *sqh;
proc_t *p = curproc;
/* The si_code value must indicate the signal will be queued */
if (pid <= 0 || !sigwillqueue(sig, si_code))
return (set_errno(EINVAL));
if ((sqh = p->p_sigqhdr) == NULL) {
rlim64_t sigqsz_max;
mutex_enter(&p->p_lock);
sigqsz_max = rctl_enforced_value(rc_process_sigqueue,
p->p_rctls, p);
mutex_exit(&p->p_lock);
/* Allocate sigqueue pool first time */
sqh = sigqhdralloc(sizeof (sigqueue_t), (uint_t)sigqsz_max);
mutex_enter(&p->p_lock);
if (p->p_sigqhdr == NULL) {
/* hang the pool head on proc */
p->p_sigqhdr = sqh;
} else {
/* another lwp allocated the pool, free ours */
sigqhdrfree(sqh);
sqh = p->p_sigqhdr;
}
mutex_exit(&p->p_lock);
}
do {
bzero(&v, sizeof (v));
v.sig = sig;
v.checkperm = 1;
v.sicode = si_code;
v.value.sival_ptr = value;
if ((error = sigqkill(pid, &v)) != EAGAIN || !block)
break;
/* block waiting for another chance to allocate a sigqueue_t */
mutex_enter(&sqh->sqb_lock);
while (sqh->sqb_count == 0) {
if (!cv_wait_sig(&sqh->sqb_cv, &sqh->sqb_lock)) {
error = EINTR;
break;
}
}
mutex_exit(&sqh->sqb_lock);
} while (error == EAGAIN);
if (error)
return (set_errno(error));
return (0);
}
#ifdef _SYSCALL32_IMPL
/*
* sigqueue32 - System call entry point for 32-bit callers on LP64 kernel,
* needed to handle the 32-bit sigvals as correctly as we can. We always
* assume that a 32-bit caller is passing an int. A 64-bit recipient
* that expects an int will therefore get it correctly. A 32-bit
* recipient will also get it correctly since siginfo_kto32() uses
* sival_int in the conversion. Since a 32-bit pointer has the same
* size and address in the sigval, it also converts correctly so that
* two 32-bit apps can exchange a pointer value. However, this means
* that a pointer sent by a 32-bit caller will be seen in the upper half
* by a 64-bit recipient, and only the upper half of a 64-bit pointer will
* be seen by a 32-bit recipient. This is the best solution that does
* not require severe hacking of the sigval union. Anyways, what it
* means to be sending pointers between processes with dissimilar
* models is unclear.
*/
int
sigqueue32(pid_t pid, int sig, /* union sigval32 */ caddr32_t value,
int si_code, int block)
{
union sigval sv;
bzero(&sv, sizeof (sv));
sv.sival_int = (int)value;
return (sigqueue(pid, sig, sv.sival_ptr, si_code, block));
}
#endif