HardenedBSD/sys/compat/svr4/svr4_signal.c

/*-
 * Copyright (c) 1998 Mark Newton
 * Copyright (c) 1994 Christos Zoulas
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 * 3. The name of the author may not be used to endorse or promote products
 *    derived from this software without specific prior written permission
 *
 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 */

#include <sys/cdefs.h>
__FBSDID("$FreeBSD$");

#include <sys/param.h>
#include <sys/systm.h>
#include <sys/filedesc.h>
#include <sys/lock.h>
#include <sys/mutex.h>
#include <sys/proc.h>
#include <sys/signal.h>
#include <sys/signalvar.h>
#include <sys/syscallsubr.h>
#include <sys/sysproto.h>

#include <machine/cpu.h>

#include <compat/svr4/svr4.h>
#include <compat/svr4/svr4_types.h>
#include <compat/svr4/svr4_signal.h>
#include <compat/svr4/svr4_proto.h>
#include <compat/svr4/svr4_util.h>
#include <compat/svr4/svr4_ucontext.h>

#define	svr4_sigmask(n)		(1 << (((n) - 1) & 31))
#define	svr4_sigword(n)		(((n) - 1) >> 5)
#define svr4_sigemptyset(s)	memset((s), 0, sizeof(*(s)))
#define	svr4_sigismember(s, n)	((s)->bits[svr4_sigword(n)] & svr4_sigmask(n))
#define	svr4_sigaddset(s, n)	((s)->bits[svr4_sigword(n)] |= svr4_sigmask(n))

void svr4_to_bsd_sigaction(const struct svr4_sigaction *, struct sigaction *);
void bsd_to_svr4_sigaction(const struct sigaction *, struct svr4_sigaction *);
void svr4_sigfillset(svr4_sigset_t *);

int bsd_to_svr4_sig[SVR4_NSIG] = {
	0,
	SVR4_SIGHUP,
	SVR4_SIGINT,
	SVR4_SIGQUIT,
	SVR4_SIGILL,
	SVR4_SIGTRAP,
	SVR4_SIGABRT,
	SVR4_SIGEMT,
	SVR4_SIGFPE,
	SVR4_SIGKILL,
	SVR4_SIGBUS,
	SVR4_SIGSEGV,
	SVR4_SIGSYS,
	SVR4_SIGPIPE,
	SVR4_SIGALRM,
	SVR4_SIGTERM,
	SVR4_SIGURG,
	SVR4_SIGSTOP,
	SVR4_SIGTSTP,
	SVR4_SIGCONT,
	SVR4_SIGCHLD,
	SVR4_SIGTTIN,
	SVR4_SIGTTOU,
	SVR4_SIGIO,
	SVR4_SIGXCPU,
	SVR4_SIGXFSZ,
	SVR4_SIGVTALRM,
	SVR4_SIGPROF,
	SVR4_SIGWINCH,
	0,			/* SIGINFO */
	SVR4_SIGUSR1,
	SVR4_SIGUSR2,
};

int svr4_to_bsd_sig[SVR4_NSIG] = {
	0,
	SIGHUP,
	SIGINT,
	SIGQUIT,
	SIGILL,
	SIGTRAP,
	SIGABRT,
	SIGEMT,
	SIGFPE,
	SIGKILL,
	SIGBUS,
	SIGSEGV,
	SIGSYS,
	SIGPIPE,
	SIGALRM,
	SIGTERM,
	SIGUSR1,
	SIGUSR2,
	SIGCHLD,
	0,		/* XXX NetBSD uses SIGPWR here, but we don't seem to have one */
	SIGWINCH,
	SIGURG,
	SIGIO,
	SIGSTOP,
	SIGTSTP,
	SIGCONT,
	SIGTTIN,
	SIGTTOU,
	SIGVTALRM,
	SIGPROF,
	SIGXCPU,
	SIGXFSZ,
};

void
svr4_sigfillset(s)
	svr4_sigset_t *s;
{
	int i;

	svr4_sigemptyset(s);
	for (i = 1; i < SVR4_NSIG; i++) 
		if (svr4_to_bsd_sig[i] != 0)
			svr4_sigaddset(s, i);
}

void
svr4_to_bsd_sigset(sss, bss)
	const svr4_sigset_t *sss;
	sigset_t *bss;
{
	int i, newsig;

	SIGEMPTYSET(*bss);
	for (i = 1; i < SVR4_NSIG; i++)
		if (svr4_sigismember(sss, i)) {
			newsig = svr4_to_bsd_sig[i];
			if (newsig)
				SIGADDSET(*bss, newsig);
		}
}

void
bsd_to_svr4_sigset(bss, sss)
	const sigset_t *bss;
	svr4_sigset_t *sss;
{
	int i, newsig;

	svr4_sigemptyset(sss);
	for (i = 1; i < SVR4_NSIG; i++) {
		if (SIGISMEMBER(*bss, i)) {
			newsig = bsd_to_svr4_sig[i];
			if (newsig)
				svr4_sigaddset(sss, newsig);
		}
	}
}

/*
 * XXX: Only a subset of the flags is currently implemented.
 */
void
svr4_to_bsd_sigaction(ssa, bsa)
	const struct svr4_sigaction *ssa;
	struct sigaction *bsa;
{

	bsa->sa_handler = (sig_t) ssa->ssa_handler;
	svr4_to_bsd_sigset(&ssa->ssa_mask, &bsa->sa_mask);
	bsa->sa_flags = 0;
	if ((ssa->ssa_flags & SVR4_SA_ONSTACK) != 0)
		bsa->sa_flags |= SA_ONSTACK;
	if ((ssa->ssa_flags & SVR4_SA_RESETHAND) != 0)
		bsa->sa_flags |= SA_RESETHAND;
	if ((ssa->ssa_flags & SVR4_SA_RESTART) != 0)
		bsa->sa_flags |= SA_RESTART;
	if ((ssa->ssa_flags & SVR4_SA_SIGINFO) != 0)
		DPRINTF(("svr4_to_bsd_sigaction: SA_SIGINFO ignored\n"));
	if ((ssa->ssa_flags & SVR4_SA_NOCLDSTOP) != 0)
		bsa->sa_flags |= SA_NOCLDSTOP;
	if ((ssa->ssa_flags & SVR4_SA_NODEFER) != 0)
		bsa->sa_flags |= SA_NODEFER;
	if ((ssa->ssa_flags & SVR4_SA_NOCLDWAIT) != 0)
		bsa->sa_flags |= SA_NOCLDWAIT;
	if ((ssa->ssa_flags & ~SVR4_SA_ALLBITS) != 0)
		DPRINTF(("svr4_to_bsd_sigaction: extra bits ignored\n"));
}

void
bsd_to_svr4_sigaction(bsa, ssa)
	const struct sigaction *bsa;
	struct svr4_sigaction *ssa;
{

	ssa->ssa_handler = (svr4_sig_t) bsa->sa_handler;
	bsd_to_svr4_sigset(&bsa->sa_mask, &ssa->ssa_mask);
	ssa->ssa_flags = 0;
	if ((bsa->sa_flags & SA_ONSTACK) != 0)
		ssa->ssa_flags |= SVR4_SA_ONSTACK;
	if ((bsa->sa_flags & SA_RESETHAND) != 0)
		ssa->ssa_flags |= SVR4_SA_RESETHAND;
	if ((bsa->sa_flags & SA_RESTART) != 0)
		ssa->ssa_flags |= SVR4_SA_RESTART;
	if ((bsa->sa_flags & SA_NODEFER) != 0)
		ssa->ssa_flags |= SVR4_SA_NODEFER;
	if ((bsa->sa_flags & SA_NOCLDSTOP) != 0)
		ssa->ssa_flags |= SVR4_SA_NOCLDSTOP;
}

void
svr4_to_bsd_sigaltstack(sss, bss)
	const struct svr4_sigaltstack *sss;
	struct sigaltstack *bss;
{

	bss->ss_sp = sss->ss_sp;
	bss->ss_size = sss->ss_size;
	bss->ss_flags = 0;
	if ((sss->ss_flags & SVR4_SS_DISABLE) != 0)
		bss->ss_flags |= SS_DISABLE;
	if ((sss->ss_flags & SVR4_SS_ONSTACK) != 0)
		bss->ss_flags |= SS_ONSTACK;
	if ((sss->ss_flags & ~SVR4_SS_ALLBITS) != 0)
	  /*XXX*/ uprintf("svr4_to_bsd_sigaltstack: extra bits ignored\n");
}

void
bsd_to_svr4_sigaltstack(bss, sss)
	const struct sigaltstack *bss;
	struct svr4_sigaltstack *sss;
{

	sss->ss_sp = bss->ss_sp;
	sss->ss_size = bss->ss_size;
	sss->ss_flags = 0;
	if ((bss->ss_flags & SS_DISABLE) != 0)
		sss->ss_flags |= SVR4_SS_DISABLE;
	if ((bss->ss_flags & SS_ONSTACK) != 0)
		sss->ss_flags |= SVR4_SS_ONSTACK;
}

int
svr4_sys_sigaction(td, uap)
	struct thread *td;
	struct svr4_sys_sigaction_args *uap;
{
	struct svr4_sigaction isa;
	struct sigaction nbsa, obsa;
	struct sigaction *nbsap;
	int error;

	if (uap->signum < 0 || uap->signum >= SVR4_NSIG)
		return (EINVAL);

	DPRINTF(("@@@ svr4_sys_sigaction(%d, %d, %d)\n", td->td_proc->p_pid,
			uap->signum,
			SVR4_SVR42BSD_SIG(uap->signum)));
	
	if (uap->nsa != NULL) {
		if ((error = copyin(uap->nsa, &isa, sizeof(isa))) != 0)
			return (error);
		svr4_to_bsd_sigaction(&isa, &nbsa);
		nbsap = &nbsa;
	} else
		nbsap = NULL;
#if defined(DEBUG_SVR4)
	{
		int i;
		for (i = 0; i < 4; i++) 
			DPRINTF(("\tssa_mask[%d] = %lx\n", i,
						isa.ssa_mask.bits[i]));
		DPRINTF(("\tssa_handler = %p\n", isa.ssa_handler));
	}
#endif
	error = kern_sigaction(td, SVR4_SVR42BSD_SIG(uap->signum), nbsap, &obsa,
	    0);
	if (error == 0 && uap->osa != NULL) {
		bsd_to_svr4_sigaction(&obsa, &isa);
		error = copyout(&isa, uap->osa, sizeof(isa));
	}
	return (error);
}

int 
svr4_sys_sigaltstack(td, uap)
	struct thread *td;
	struct svr4_sys_sigaltstack_args *uap;
{
	struct svr4_sigaltstack sss;
	struct sigaltstack nbss, obss, *nbssp;
	int error;

	if (uap->nss != NULL) {
		if ((error = copyin(uap->nss, &sss, sizeof(sss))) != 0)
			return (error);
		svr4_to_bsd_sigaltstack(&sss, &nbss);
		nbssp = &nbss;
	} else
		nbssp = NULL;
	error = kern_sigaltstack(td, nbssp, &obss);
	if (error == 0 && uap->oss != NULL) {
		bsd_to_svr4_sigaltstack(&obss, &sss);
		error = copyout(&sss, uap->oss, sizeof(sss));
	}
	return (error);
}

/*
 * Stolen from the ibcs2 one
 */
int
svr4_sys_signal(td, uap)
	struct thread *td;
	struct svr4_sys_signal_args *uap;
{
	struct proc *p;
	int signum;
	int error;

	p = td->td_proc;
	DPRINTF(("@@@ svr4_sys_signal(%d)\n", p->p_pid));

	signum = SVR4_SIGNO(uap->signum);
	if (signum < 0 || signum >= SVR4_NSIG) {
		if (SVR4_SIGCALL(uap->signum) == SVR4_SIGNAL_MASK ||
		    SVR4_SIGCALL(uap->signum) == SVR4_SIGDEFER_MASK)
			td->td_retval[0] = (int)SVR4_SIG_ERR;
		return (EINVAL);
	}
	signum = SVR4_SVR42BSD_SIG(signum);

	switch (SVR4_SIGCALL(uap->signum)) {
	case SVR4_SIGDEFER_MASK:
		if (uap->handler == SVR4_SIG_HOLD)
			goto sighold;
		/* FALLTHROUGH */

	case SVR4_SIGNAL_MASK:
		{
			struct sigaction nbsa, obsa;

			nbsa.sa_handler = (sig_t) uap->handler;
			SIGEMPTYSET(nbsa.sa_mask);
			nbsa.sa_flags = 0;
			if (signum != SIGALRM)
				nbsa.sa_flags = SA_RESTART;
			error = kern_sigaction(td, signum, &nbsa, &obsa, 0);
			if (error != 0) {
				DPRINTF(("signal: sigaction failed: %d\n",
					 error));
				td->td_retval[0] = (int)SVR4_SIG_ERR;
				return (error);
			}
			td->td_retval[0] = (int)obsa.sa_handler;
			return (0);
		}

	case SVR4_SIGHOLD_MASK:
sighold:
		{
			sigset_t set;

			SIGEMPTYSET(set);
			SIGADDSET(set, signum);
			return (kern_sigprocmask(td, SIG_BLOCK, &set, NULL, 0));
		}

	case SVR4_SIGRELSE_MASK:
		{
			sigset_t set;

			SIGEMPTYSET(set);
			SIGADDSET(set, signum);
			return (kern_sigprocmask(td, SIG_UNBLOCK, &set, NULL,
				    0));
		}

	case SVR4_SIGIGNORE_MASK:
		{
			struct sigaction sa;

			sa.sa_handler = SIG_IGN;
			SIGEMPTYSET(sa.sa_mask);
			sa.sa_flags = 0;
			error = kern_sigaction(td, signum, &sa, NULL, 0);
			if (error != 0)
				DPRINTF(("sigignore: sigaction failed\n"));
			return (error);
		}

	case SVR4_SIGPAUSE_MASK:
		{
			sigset_t mask;

			PROC_LOCK(p);
			mask = td->td_sigmask;
			PROC_UNLOCK(p);
			SIGDELSET(mask, signum);
			return kern_sigsuspend(td, mask);
		}

	default:
		return (ENOSYS);
	}
}


int
svr4_sys_sigprocmask(td, uap)
	struct thread *td;
	struct svr4_sys_sigprocmask_args *uap;
{
	svr4_sigset_t sss;
	sigset_t oss, nss;
	sigset_t *nssp;
	int error;

	if (uap->set != NULL) {
		if ((error = copyin(uap->set, &sss, sizeof(sss))) != 0)
			return error;
		svr4_to_bsd_sigset(&sss, &nss);
		nssp = &nss;
	} else
		nssp = NULL;

	/* SVR/4 sigprocmask flag values are the same as the FreeBSD values. */
	error = kern_sigprocmask(td, uap->how, nssp, &oss, 0);
	if (error == 0 && uap->oset != NULL) {
		bsd_to_svr4_sigset(&oss, &sss);
		error = copyout(&sss, uap->oset, sizeof(sss));
	}
	return (error);
}

int
svr4_sys_sigpending(td, uap)
	struct thread *td;
	struct svr4_sys_sigpending_args *uap;
{
	struct proc *p;
	sigset_t bss;
	svr4_sigset_t sss;

	p = td->td_proc;
	DPRINTF(("@@@ svr4_sys_sigpending(%d)\n", p->p_pid));
	switch (uap->what) {
	case 1:	/* sigpending */
		if (uap->mask == NULL)
			return 0;
		PROC_LOCK(p);
		bss = p->p_siglist;
		SIGSETOR(bss, td->td_siglist);
		SIGSETAND(bss, td->td_sigmask);
		PROC_UNLOCK(p);
		bsd_to_svr4_sigset(&bss, &sss);
		break;

	case 2:	/* sigfillset */
		svr4_sigfillset(&sss);
#if defined(DEBUG_SVR4)
		{
			int i;
			for (i = 0; i < 4; i++)
				DPRINTF(("new sigset[%d] = %lx\n", i, (long)sss.bits[i]));
		}
#endif
		break;

	default:
		return EINVAL;
	}
		
	return copyout(&sss, uap->mask, sizeof(sss));
}

int
svr4_sys_sigsuspend(td, uap)
	struct thread *td;
	struct svr4_sys_sigsuspend_args *uap;
{
	svr4_sigset_t sss;
	sigset_t bss;
	int error;

	if ((error = copyin(uap->ss, &sss, sizeof(sss))) != 0)
		return error;

	svr4_to_bsd_sigset(&sss, &bss);
	return kern_sigsuspend(td, bss);
}


int
svr4_sys_kill(td, uap)
	struct thread *td;
	struct svr4_sys_kill_args *uap;
{
	struct kill_args ka;

	if (uap->signum < 0 || uap->signum >= SVR4_NSIG)
		return (EINVAL);
	ka.pid = uap->pid;
	ka.signum = SVR4_SVR42BSD_SIG(uap->signum);
	return sys_kill(td, &ka);
}


int 
svr4_sys_context(td, uap)
	struct thread *td;
	struct svr4_sys_context_args *uap;
{
	struct svr4_ucontext uc;
	int error, onstack;

	switch (uap->func) {
	case 0:
		DPRINTF(("getcontext(%p)\n", uap->uc));
		PROC_LOCK(td->td_proc);
		onstack = sigonstack(cpu_getstack(td));
		PROC_UNLOCK(td->td_proc);
		svr4_getcontext(td, &uc, &td->td_sigmask, onstack);
		return copyout(&uc, uap->uc, sizeof(uc));

	case 1: 
		DPRINTF(("setcontext(%p)\n", uap->uc));
		if ((error = copyin(uap->uc, &uc, sizeof(uc))) != 0)
			return error;
		DPRINTF(("uc_flags = %lx\n", uc.uc_flags));
#if defined(DEBUG_SVR4)
		{
			int i;
			for (i = 0; i < 4; i++)
				DPRINTF(("uc_sigmask[%d] = %lx\n", i,
							uc.uc_sigmask.bits[i]));
		}
#endif
		return svr4_setcontext(td, &uc);

	default:
		DPRINTF(("context(%d, %p)\n", uap->func,
		    uap->uc));
		return ENOSYS;
	}
	return 0;
}

int
svr4_sys_pause(td, uap)
	struct thread *td;
	struct svr4_sys_pause_args *uap;
{
	sigset_t mask;

	PROC_LOCK(td->td_proc);
	mask = td->td_sigmask;
	PROC_UNLOCK(td->td_proc);
	return kern_sigsuspend(td, mask);
}