xref: /netbsd-src/sys/kern/sys_ptrace_common.c (revision fc4f42693f9b1c31f39f9cf50af1bf2010325808)
1 /*	$NetBSD: sys_ptrace_common.c,v 1.36 2018/04/08 14:46:32 kamil Exp $	*/
2 
3 /*-
4  * Copyright (c) 2008, 2009 The NetBSD Foundation, Inc.
5  * All rights reserved.
6  *
7  * This code is derived from software contributed to The NetBSD Foundation
8  * by Andrew Doran.
9  *
10  * Redistribution and use in source and binary forms, with or without
11  * modification, are permitted provided that the following conditions
12  * are met:
13  * 1. Redistributions of source code must retain the above copyright
14  *    notice, this list of conditions and the following disclaimer.
15  * 2. Redistributions in binary form must reproduce the above copyright
16  *    notice, this list of conditions and the following disclaimer in the
17  *    documentation and/or other materials provided with the distribution.
18  *
19  * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
20  * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
21  * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
22  * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
23  * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
24  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
25  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
26  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
27  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
28  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
29  * POSSIBILITY OF SUCH DAMAGE.
30  */
31 
32 /*-
33  * Copyright (c) 1982, 1986, 1989, 1993
34  *	The Regents of the University of California.  All rights reserved.
35  * (c) UNIX System Laboratories, Inc.
36  * All or some portions of this file are derived from material licensed
37  * to the University of California by American Telephone and Telegraph
38  * Co. or Unix System Laboratories, Inc. and are reproduced herein with
39  * the permission of UNIX System Laboratories, Inc.
40  *
41  * This code is derived from software contributed to Berkeley by
42  * Jan-Simon Pendry.
43  *
44  * Redistribution and use in source and binary forms, with or without
45  * modification, are permitted provided that the following conditions
46  * are met:
47  * 1. Redistributions of source code must retain the above copyright
48  *    notice, this list of conditions and the following disclaimer.
49  * 2. Redistributions in binary form must reproduce the above copyright
50  *    notice, this list of conditions and the following disclaimer in the
51  *    documentation and/or other materials provided with the distribution.
52  * 3. Neither the name of the University nor the names of its contributors
53  *    may be used to endorse or promote products derived from this software
54  *    without specific prior written permission.
55  *
56  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
57  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
58  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
59  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
60  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
61  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
62  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
63  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
64  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
65  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
66  * SUCH DAMAGE.
67  *
68  *	from: @(#)sys_process.c	8.1 (Berkeley) 6/10/93
69  */
70 
71 /*-
72  * Copyright (c) 1993 Jan-Simon Pendry.
73  * Copyright (c) 1994 Christopher G. Demetriou.  All rights reserved.
74  *
75  * This code is derived from software contributed to Berkeley by
76  * Jan-Simon Pendry.
77  *
78  * Redistribution and use in source and binary forms, with or without
79  * modification, are permitted provided that the following conditions
80  * are met:
81  * 1. Redistributions of source code must retain the above copyright
82  *    notice, this list of conditions and the following disclaimer.
83  * 2. Redistributions in binary form must reproduce the above copyright
84  *    notice, this list of conditions and the following disclaimer in the
85  *    documentation and/or other materials provided with the distribution.
86  * 3. All advertising materials mentioning features or use of this software
87  *    must display the following acknowledgement:
88  *	This product includes software developed by the University of
89  *	California, Berkeley and its contributors.
90  * 4. Neither the name of the University nor the names of its contributors
91  *    may be used to endorse or promote products derived from this software
92  *    without specific prior written permission.
93  *
94  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
95  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
96  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
97  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
98  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
99  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
100  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
101  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
102  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
103  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
104  * SUCH DAMAGE.
105  *
106  *	from: @(#)sys_process.c	8.1 (Berkeley) 6/10/93
107  */
108 
109 /*
110  * References:
111  *	(1) Bach's "The Design of the UNIX Operating System",
112  *	(2) sys/miscfs/procfs from UCB's 4.4BSD-Lite distribution,
113  *	(3) the "4.4BSD Programmer's Reference Manual" published
114  *		by USENIX and O'Reilly & Associates.
115  * The 4.4BSD PRM does a reasonably good job of documenting what the various
116  * ptrace() requests should actually do, and its text is quoted several times
117  * in this file.
118  */
119 
120 #include <sys/cdefs.h>
121 __KERNEL_RCSID(0, "$NetBSD: sys_ptrace_common.c,v 1.36 2018/04/08 14:46:32 kamil Exp $");
122 
123 #ifdef _KERNEL_OPT
124 #include "opt_ptrace.h"
125 #include "opt_ktrace.h"
126 #include "opt_pax.h"
127 #include "opt_compat_netbsd32.h"
128 #endif
129 
130 #if defined(__HAVE_COMPAT_NETBSD32) && !defined(COMPAT_NETBSD32) \
131     && !defined(_RUMPKERNEL)
132 #define COMPAT_NETBSD32
133 #endif
134 
135 #include <sys/param.h>
136 #include <sys/systm.h>
137 #include <sys/proc.h>
138 #include <sys/errno.h>
139 #include <sys/exec.h>
140 #include <sys/pax.h>
141 #include <sys/ptrace.h>
142 #include <sys/uio.h>
143 #include <sys/ras.h>
144 #include <sys/kmem.h>
145 #include <sys/kauth.h>
146 #include <sys/mount.h>
147 #include <sys/syscallargs.h>
148 #include <sys/module.h>
149 #include <sys/condvar.h>
150 #include <sys/mutex.h>
151 
152 #include <uvm/uvm_extern.h>
153 
154 #include <machine/reg.h>
155 
156 #ifdef PTRACE
157 
158 # ifdef DEBUG
159 #  define DPRINTF(a) uprintf a
160 # else
161 #  define DPRINTF(a)
162 # endif
163 
164 static kauth_listener_t ptrace_listener;
165 static int process_auxv_offset(struct proc *, struct uio *);
166 
167 #if 0
168 static int ptrace_cbref;
169 static kmutex_t ptrace_mtx;
170 static kcondvar_t ptrace_cv;
171 #endif
172 
173 #ifdef PT_GETREGS
174 # define case_PT_GETREGS	case PT_GETREGS:
175 #else
176 # define case_PT_GETREGS
177 #endif
178 
179 #ifdef PT_SETREGS
180 # define case_PT_SETREGS	case PT_SETREGS:
181 #else
182 # define case_PT_SETREGS
183 #endif
184 
185 #ifdef PT_GETFPREGS
186 # define case_PT_GETFPREGS	case PT_GETFPREGS:
187 #else
188 # define case_PT_GETFPREGS
189 #endif
190 
191 #ifdef PT_SETFPREGS
192 # define case_PT_SETFPREGS	case PT_SETFPREGS:
193 #else
194 # define case_PT_SETFPREGS
195 #endif
196 
197 #ifdef PT_GETDBREGS
198 # define case_PT_GETDBREGS	case PT_GETDBREGS:
199 #else
200 # define case_PT_GETDBREGS
201 #endif
202 
203 #ifdef PT_SETDBREGS
204 # define case_PT_SETDBREGS	case PT_SETDBREGS:
205 #else
206 # define case_PT_SETDBREGS
207 #endif
208 
209 #if defined(PT_SETREGS) || defined(PT_GETREGS) || \
210     defined(PT_SETFPREGS) || defined(PT_GETFOREGS) || \
211     defined(PT_SETDBREGS) || defined(PT_GETDBREGS)
212 # define PT_REGISTERS
213 #endif
214 
215 static int
216 ptrace_listener_cb(kauth_cred_t cred, kauth_action_t action, void *cookie,
217     void *arg0, void *arg1, void *arg2, void *arg3)
218 {
219 	struct proc *p;
220 	int result;
221 #ifdef PT_SETDBREGS
222 	extern int user_set_dbregs;
223 #endif
224 
225 	result = KAUTH_RESULT_DEFER;
226 	p = arg0;
227 
228 #if 0
229 	mutex_enter(&ptrace_mtx);
230 	ptrace_cbref++;
231 	mutex_exit(&ptrace_mtx);
232 #endif
233 	if (action != KAUTH_PROCESS_PTRACE)
234 		goto out;
235 
236 	switch ((u_long)arg1) {
237 #ifdef PT_SETDBREGS
238 	case_PT_SETDBREGS
239 		if (kauth_cred_getuid(cred) != 0 && user_set_dbregs == 0) {
240 			result = KAUTH_RESULT_DENY;
241 			break;
242 		}
243 #endif
244 	case PT_TRACE_ME:
245 	case PT_ATTACH:
246 	case PT_WRITE_I:
247 	case PT_WRITE_D:
248 	case PT_READ_I:
249 	case PT_READ_D:
250 	case PT_IO:
251 	case_PT_GETREGS
252 	case_PT_SETREGS
253 	case_PT_GETFPREGS
254 	case_PT_SETFPREGS
255 	case_PT_GETDBREGS
256 	case PT_SET_EVENT_MASK:
257 	case PT_GET_EVENT_MASK:
258 	case PT_GET_PROCESS_STATE:
259 	case PT_SET_SIGINFO:
260 	case PT_GET_SIGINFO:
261 #ifdef __HAVE_PTRACE_MACHDEP
262 	PTRACE_MACHDEP_REQUEST_CASES
263 #endif
264 		if (kauth_cred_getuid(cred) != kauth_cred_getuid(p->p_cred) ||
265 		    ISSET(p->p_flag, PK_SUGID)) {
266 			break;
267 		}
268 
269 		result = KAUTH_RESULT_ALLOW;
270 
271 	break;
272 
273 #ifdef PT_STEP
274 	case PT_STEP:
275 	case PT_SETSTEP:
276 	case PT_CLEARSTEP:
277 #endif
278 	case PT_CONTINUE:
279 	case PT_KILL:
280 	case PT_DETACH:
281 	case PT_LWPINFO:
282 	case PT_SYSCALL:
283 	case PT_SYSCALLEMU:
284 	case PT_DUMPCORE:
285 	case PT_RESUME:
286 	case PT_SUSPEND:
287 		result = KAUTH_RESULT_ALLOW;
288 		break;
289 
290 	default:
291 		break;
292 	}
293 
294  out:
295 #if 0
296 	mutex_enter(&ptrace_mtx);
297 	if (--ptrace_cbref == 0)
298 		cv_broadcast(&ptrace_cv);
299 	mutex_exit(&ptrace_mtx);
300 #endif
301 
302 	return result;
303 }
304 
305 int
306 ptrace_init(void)
307 {
308 
309 #if 0
310 	mutex_init(&ptrace_mtx, MUTEX_DEFAULT, IPL_NONE);
311 	cv_init(&ptrace_cv, "ptracecb");
312 	ptrace_cbref = 0;
313 #endif
314 	ptrace_listener = kauth_listen_scope(KAUTH_SCOPE_PROCESS,
315 	    ptrace_listener_cb, NULL);
316 	return 0;
317 }
318 
319 int
320 ptrace_fini(void)
321 {
322 
323 	kauth_unlisten_scope(ptrace_listener);
324 
325 #if 0
326 	/* Make sure no-one is executing our kauth listener */
327 
328 	mutex_enter(&ptrace_mtx);
329 	while (ptrace_cbref != 0)
330 		cv_wait(&ptrace_cv, &ptrace_mtx);
331 	mutex_exit(&ptrace_mtx);
332 	mutex_destroy(&ptrace_mtx);
333 	cv_destroy(&ptrace_cv);
334 #endif
335 
336 	return 0;
337 }
338 
339 static struct proc *
340 ptrace_find(struct lwp *l, int req, pid_t pid)
341 {
342 	struct proc *t;
343 
344 	/* "A foolish consistency..." XXX */
345 	if (req == PT_TRACE_ME) {
346 		t = l->l_proc;
347 		mutex_enter(t->p_lock);
348 		return t;
349 	}
350 
351 	/* Find the process we're supposed to be operating on. */
352 	t = proc_find(pid);
353 	if (t == NULL)
354 		return NULL;
355 
356 	/* XXX-elad */
357 	mutex_enter(t->p_lock);
358 	int error = kauth_authorize_process(l->l_cred, KAUTH_PROCESS_CANSEE,
359 	    t, KAUTH_ARG(KAUTH_REQ_PROCESS_CANSEE_ENTRY), NULL, NULL);
360 	if (error) {
361 		mutex_exit(t->p_lock);
362 		return NULL;
363 	}
364 	return t;
365 }
366 
367 static int
368 ptrace_allowed(struct lwp *l, int req, struct proc *t, struct proc *p)
369 {
370 	/*
371 	 * Grab a reference on the process to prevent it from execing or
372 	 * exiting.
373 	 */
374 	if (!rw_tryenter(&t->p_reflock, RW_READER))
375 		return EBUSY;
376 
377 	/* Make sure we can operate on it. */
378 	switch (req) {
379 	case PT_TRACE_ME:
380 		/* Saying that you're being traced is always legal. */
381 		return 0;
382 
383 	case PT_ATTACH:
384 		/*
385 		 * You can't attach to a process if:
386 		 *	(1) it's the process that's doing the attaching,
387 		 */
388 		if (t->p_pid == p->p_pid)
389 			return EINVAL;
390 
391 		/*
392 		 *  (2) it's a system process
393 		 */
394 		if (t->p_flag & PK_SYSTEM)
395 			return EPERM;
396 
397 		/*
398 		 *	(3) it's already being traced, or
399 		 */
400 		if (ISSET(t->p_slflag, PSL_TRACED))
401 			return EBUSY;
402 
403 		/*
404 		 * 	(4) the tracer is chrooted, and its root directory is
405 		 * 	    not at or above the root directory of the tracee
406 		 */
407 		mutex_exit(t->p_lock);	/* XXXSMP */
408 		int tmp = proc_isunder(t, l);
409 		mutex_enter(t->p_lock);	/* XXXSMP */
410 		if (!tmp)
411 			return EPERM;
412 		return 0;
413 
414 	case PT_READ_I:
415 	case PT_READ_D:
416 	case PT_WRITE_I:
417 	case PT_WRITE_D:
418 	case PT_IO:
419 	case PT_SET_SIGINFO:
420 	case PT_GET_SIGINFO:
421 	case_PT_GETREGS
422 	case_PT_SETREGS
423 	case_PT_GETFPREGS
424 	case_PT_SETFPREGS
425 	case_PT_GETDBREGS
426 	case_PT_SETDBREGS
427 #ifdef __HAVE_PTRACE_MACHDEP
428 	PTRACE_MACHDEP_REQUEST_CASES
429 #endif
430 		/*
431 		 * You can't read/write the memory or registers of a process
432 		 * if the tracer is chrooted, and its root directory is not at
433 		 * or above the root directory of the tracee.
434 		 */
435 		mutex_exit(t->p_lock);	/* XXXSMP */
436 		tmp = proc_isunder(t, l);
437 		mutex_enter(t->p_lock);	/* XXXSMP */
438 		if (!tmp)
439 			return EPERM;
440 		/*FALLTHROUGH*/
441 
442 	case PT_CONTINUE:
443 	case PT_KILL:
444 	case PT_DETACH:
445 	case PT_LWPINFO:
446 	case PT_SYSCALL:
447 	case PT_SYSCALLEMU:
448 	case PT_DUMPCORE:
449 #ifdef PT_STEP
450 	case PT_STEP:
451 	case PT_SETSTEP:
452 	case PT_CLEARSTEP:
453 #endif
454 	case PT_SET_EVENT_MASK:
455 	case PT_GET_EVENT_MASK:
456 	case PT_GET_PROCESS_STATE:
457 	case PT_RESUME:
458 	case PT_SUSPEND:
459 		/*
460 		 * You can't do what you want to the process if:
461 		 *	(1) It's not being traced at all,
462 		 */
463 		if (!ISSET(t->p_slflag, PSL_TRACED))
464 			return EPERM;
465 
466 		/*
467 		 *	(2) it's not being traced by _you_, or
468 		 */
469 		if (t->p_pptr != p) {
470 			DPRINTF(("parent %d != %d\n", t->p_pptr->p_pid,
471 			    p->p_pid));
472 			return EBUSY;
473 		}
474 
475 		/*
476 		 *	(3) it's not currently stopped.
477 		 */
478 		if (t->p_stat != SSTOP || !t->p_waited /* XXXSMP */) {
479 			DPRINTF(("stat %d flag %d\n", t->p_stat,
480 			    !t->p_waited));
481 			return EBUSY;
482 		}
483 		return 0;
484 
485 	default:			/* It was not a legal request. */
486 		return EINVAL;
487 	}
488 }
489 
490 static int
491 ptrace_needs_hold(int req)
492 {
493 	switch (req) {
494 #ifdef PT_STEP
495 	case PT_STEP:
496 #endif
497 	case PT_CONTINUE:
498 	case PT_DETACH:
499 	case PT_KILL:
500 	case PT_SYSCALL:
501 	case PT_SYSCALLEMU:
502 	case PT_ATTACH:
503 	case PT_TRACE_ME:
504 	case PT_GET_SIGINFO:
505 	case PT_SET_SIGINFO:
506 		return 1;
507 	default:
508 		return 0;
509 	}
510 }
511 
512 static int
513 ptrace_update_lwp(struct proc *t, struct lwp **lt, lwpid_t lid)
514 {
515 	if (lid == 0 || lid == (*lt)->l_lid || t->p_nlwps == 1)
516 		return 0;
517 
518 	lwp_delref(*lt);
519 
520 	mutex_enter(t->p_lock);
521 	*lt = lwp_find(t, lid);
522 	if (*lt == NULL) {
523 		mutex_exit(t->p_lock);
524 		return ESRCH;
525 	}
526 
527 	if ((*lt)->l_flag & LW_SYSTEM) {
528 		*lt = NULL;
529 		return EINVAL;
530 	}
531 
532 	lwp_addref(*lt);
533 	mutex_exit(t->p_lock);
534 
535 	return 0;
536 }
537 
538 static int
539 ptrace_get_siginfo(struct proc *t, struct ptrace_methods *ptm, void *addr,
540     size_t data)
541 {
542 	struct ptrace_siginfo psi;
543 
544 	psi.psi_siginfo._info = t->p_sigctx.ps_info;
545 	psi.psi_lwpid = t->p_sigctx.ps_lwp;
546 
547 	return ptm->ptm_copyout_siginfo(&psi, addr, data);
548 }
549 
550 static int
551 ptrace_set_siginfo(struct proc *t, struct lwp **lt, struct ptrace_methods *ptm,
552     void *addr, size_t data)
553 {
554 	struct ptrace_siginfo psi;
555 
556 	int error = ptm->ptm_copyin_siginfo(&psi, addr, data);
557 	if (error)
558 		return error;
559 
560 	/* Check that the data is a valid signal number or zero. */
561 	if (psi.psi_siginfo.si_signo < 0 || psi.psi_siginfo.si_signo >= NSIG)
562 		return EINVAL;
563 
564 	if ((error = ptrace_update_lwp(t, lt, psi.psi_lwpid)) != 0)
565 		return error;
566 
567 	t->p_sigctx.ps_faked = true;
568 	t->p_sigctx.ps_info = psi.psi_siginfo._info;
569 	t->p_sigctx.ps_lwp = psi.psi_lwpid;
570 	return 0;
571 }
572 
573 static int
574 ptrace_get_event_mask(struct proc *t, void *addr, size_t data)
575 {
576 	struct ptrace_event pe;
577 
578 	if (data != sizeof(pe)) {
579 		DPRINTF(("%s: %zu != %zu\n", __func__, data, sizeof(pe)));
580 		return EINVAL;
581 	}
582 	memset(&pe, 0, sizeof(pe));
583 	pe.pe_set_event = ISSET(t->p_slflag, PSL_TRACEFORK) ?
584 	    PTRACE_FORK : 0;
585 	pe.pe_set_event |= ISSET(t->p_slflag, PSL_TRACEVFORK) ?
586 	    PTRACE_VFORK : 0;
587 	pe.pe_set_event |= ISSET(t->p_slflag, PSL_TRACEVFORK_DONE) ?
588 	    PTRACE_VFORK_DONE : 0;
589 	pe.pe_set_event |= ISSET(t->p_slflag, PSL_TRACELWP_CREATE) ?
590 	    PTRACE_LWP_CREATE : 0;
591 	pe.pe_set_event |= ISSET(t->p_slflag, PSL_TRACELWP_EXIT) ?
592 	    PTRACE_LWP_EXIT : 0;
593 	return copyout(&pe, addr, sizeof(pe));
594 }
595 
596 static int
597 ptrace_set_event_mask(struct proc *t, void *addr, size_t data)
598 {
599 	struct ptrace_event pe;
600 	int error;
601 
602 	if (data != sizeof(pe)) {
603 		DPRINTF(("%s: %zu != %zu\n", __func__, data, sizeof(pe)));
604 		return EINVAL;
605 	}
606 	if ((error = copyin(addr, &pe, sizeof(pe))) != 0)
607 		return error;
608 
609 	if (pe.pe_set_event & PTRACE_FORK)
610 		SET(t->p_slflag, PSL_TRACEFORK);
611 	else
612 		CLR(t->p_slflag, PSL_TRACEFORK);
613 #if notyet
614 	if (pe.pe_set_event & PTRACE_VFORK)
615 		SET(t->p_slflag, PSL_TRACEVFORK);
616 	else
617 		CLR(t->p_slflag, PSL_TRACEVFORK);
618 #else
619 	if (pe.pe_set_event & PTRACE_VFORK)
620 		return ENOTSUP;
621 #endif
622 	if (pe.pe_set_event & PTRACE_VFORK_DONE)
623 		SET(t->p_slflag, PSL_TRACEVFORK_DONE);
624 	else
625 		CLR(t->p_slflag, PSL_TRACEVFORK_DONE);
626 	if (pe.pe_set_event & PTRACE_LWP_CREATE)
627 		SET(t->p_slflag, PSL_TRACELWP_CREATE);
628 	else
629 		CLR(t->p_slflag, PSL_TRACELWP_CREATE);
630 	if (pe.pe_set_event & PTRACE_LWP_EXIT)
631 		SET(t->p_slflag, PSL_TRACELWP_EXIT);
632 	else
633 		CLR(t->p_slflag, PSL_TRACELWP_EXIT);
634 	return 0;
635 }
636 
637 static int
638 ptrace_get_process_state(struct proc *t, void *addr, size_t data)
639 {
640 	struct ptrace_state ps;
641 
642 	if (data != sizeof(ps)) {
643 		DPRINTF(("%s: %zu != %zu\n", __func__, data, sizeof(ps)));
644 		return EINVAL;
645 	}
646 	memset(&ps, 0, sizeof(ps));
647 
648 	if (t->p_fpid) {
649 		ps.pe_report_event = PTRACE_FORK;
650 		ps.pe_other_pid = t->p_fpid;
651 	} else if (t->p_vfpid) {
652 		ps.pe_report_event = PTRACE_VFORK;
653 		ps.pe_other_pid = t->p_vfpid;
654 	} else if (t->p_vfpid_done) {
655 		ps.pe_report_event = PTRACE_VFORK_DONE;
656 		ps.pe_other_pid = t->p_vfpid_done;
657 	} else if (t->p_lwp_created) {
658 		ps.pe_report_event = PTRACE_LWP_CREATE;
659 		ps.pe_lwp = t->p_lwp_created;
660 	} else if (t->p_lwp_exited) {
661 		ps.pe_report_event = PTRACE_LWP_EXIT;
662 		ps.pe_lwp = t->p_lwp_exited;
663 	}
664 	return copyout(&ps, addr, sizeof(ps));
665 }
666 
667 static int
668 ptrace_lwpinfo(struct proc *t, struct lwp **lt, void *addr, size_t data)
669 {
670 	struct ptrace_lwpinfo pl;
671 
672 	if (data != sizeof(pl)) {
673 		DPRINTF(("%s: %zu != %zu\n", __func__, data, sizeof(pl)));
674 		return EINVAL;
675 	}
676 	int error = copyin(addr, &pl, sizeof(pl));
677 	if (error)
678 		return error;
679 
680 	lwpid_t tmp = pl.pl_lwpid;
681 	lwp_delref(*lt);
682 	mutex_enter(t->p_lock);
683 	if (tmp == 0)
684 		*lt = lwp_find_first(t);
685 	else {
686 		*lt = lwp_find(t, tmp);
687 		if (*lt == NULL) {
688 			mutex_exit(t->p_lock);
689 			return ESRCH;
690 		}
691 		*lt = LIST_NEXT(*lt, l_sibling);
692 	}
693 
694 	while (*lt != NULL && !lwp_alive(*lt))
695 		*lt = LIST_NEXT(*lt, l_sibling);
696 
697 	pl.pl_lwpid = 0;
698 	pl.pl_event = 0;
699 	if (*lt) {
700 		lwp_addref(*lt);
701 		pl.pl_lwpid = (*lt)->l_lid;
702 
703 		if ((*lt)->l_flag & LW_WSUSPEND)
704 			pl.pl_event = PL_EVENT_SUSPENDED;
705 		/*
706 		 * If we match the lwp, or it was sent to every lwp,
707 		 * we set PL_EVENT_SIGNAL.
708 		 * XXX: ps_lwp == 0 means everyone and noone, so
709 		 * check ps_signo too.
710 		 */
711 		else if ((*lt)->l_lid == t->p_sigctx.ps_lwp
712 			 || (t->p_sigctx.ps_lwp == 0 &&
713 			     t->p_sigctx.ps_info._signo))
714 			pl.pl_event = PL_EVENT_SIGNAL;
715 	}
716 	mutex_exit(t->p_lock);
717 
718 	return copyout(&pl, addr, sizeof(pl));
719 }
720 
721 static int
722 ptrace_startstop(struct proc *t, struct lwp **lt, int rq, void *addr,
723     size_t data)
724 {
725 	int error;
726 
727 	if ((error = ptrace_update_lwp(t, lt, data)) != 0)
728 		return error;
729 
730 	lwp_lock(*lt);
731 	if (rq == PT_SUSPEND)
732 		(*lt)->l_flag |= LW_WSUSPEND;
733 	else
734 		(*lt)->l_flag &= ~LW_WSUSPEND;
735 	lwp_unlock(*lt);
736 	return 0;
737 }
738 
739 #ifdef PT_REGISTERS
740 static int
741 ptrace_uio_dir(int req)
742 {
743 	switch (req) {
744 	case_PT_GETREGS
745 	case_PT_GETFPREGS
746 	case_PT_GETDBREGS
747 		return UIO_READ;
748 	case_PT_SETREGS
749 	case_PT_SETFPREGS
750 	case_PT_SETDBREGS
751 		return UIO_WRITE;
752 	default:
753 		return -1;
754 	}
755 }
756 
757 static int
758 ptrace_regs(struct lwp *l, struct lwp **lt, int rq, struct ptrace_methods *ptm,
759     void *addr, size_t data)
760 {
761 	int error;
762 	struct proc *t = (*lt)->l_proc;
763 	struct vmspace *vm;
764 
765 	if ((error = ptrace_update_lwp(t, lt, data)) != 0)
766 		return error;
767 
768 	int dir = ptrace_uio_dir(rq);
769 	size_t size;
770 	int (*func)(struct lwp *, struct lwp *, struct uio *);
771 
772 	switch (rq) {
773 #if defined(PT_SETREGS) || defined(PT_GETREGS)
774 	case_PT_GETREGS
775 	case_PT_SETREGS
776 		if (!process_validregs(*lt))
777 			return EINVAL;
778 		size = PROC_REGSZ(t);
779 		func = ptm->ptm_doregs;
780 		break;
781 #endif
782 #if defined(PT_SETFPREGS) || defined(PT_GETFPREGS)
783 	case_PT_GETFPREGS
784 	case_PT_SETFPREGS
785 		if (!process_validfpregs(*lt))
786 			return EINVAL;
787 		size = PROC_FPREGSZ(t);
788 		func = ptm->ptm_dofpregs;
789 		break;
790 #endif
791 #if defined(PT_SETDBREGS) || defined(PT_GETDBREGS)
792 	case_PT_GETDBREGS
793 	case_PT_SETDBREGS
794 		if (!process_validdbregs(*lt))
795 			return EINVAL;
796 		size = PROC_DBREGSZ(t);
797 		func = ptm->ptm_dodbregs;
798 		break;
799 #endif
800 	default:
801 		return EINVAL;
802 	}
803 
804 	error = proc_vmspace_getref(l->l_proc, &vm);
805 	if (error)
806 		return error;
807 
808 	struct uio uio;
809 	struct iovec iov;
810 
811 	iov.iov_base = addr;
812 	iov.iov_len = size;
813 	uio.uio_iov = &iov;
814 	uio.uio_iovcnt = 1;
815 	uio.uio_offset = 0;
816 	uio.uio_resid = iov.iov_len;
817 	uio.uio_rw = dir;
818 	uio.uio_vmspace = vm;
819 
820 	error = (*func)(l, *lt, &uio);
821 	uvmspace_free(vm);
822 	return error;
823 }
824 #endif
825 
826 static int
827 ptrace_sendsig(struct proc *t, struct lwp *lt, int signo, int resume_all)
828 {
829 	ksiginfo_t ksi;
830 
831 	t->p_fpid = 0;
832 	t->p_vfpid = 0;
833 	t->p_vfpid_done = 0;
834 	t->p_lwp_created = 0;
835 	t->p_lwp_exited = 0;
836 
837 	/* Finally, deliver the requested signal (or none). */
838 	if (t->p_stat == SSTOP) {
839 		/*
840 		 * Unstop the process.  If it needs to take a
841 		 * signal, make all efforts to ensure that at
842 		 * an LWP runs to see it.
843 		 */
844 		t->p_xsig = signo;
845 		if (resume_all)
846 			proc_unstop(t);
847 		else
848 			lwp_unstop(lt);
849 		return 0;
850 	}
851 
852 	KSI_INIT_EMPTY(&ksi);
853 	if (t->p_sigctx.ps_faked) {
854 		if (signo != t->p_sigctx.ps_info._signo)
855 			return EINVAL;
856 		t->p_sigctx.ps_faked = false;
857 		ksi.ksi_info = t->p_sigctx.ps_info;
858 		ksi.ksi_lid = t->p_sigctx.ps_lwp;
859 	} else if (signo == 0) {
860 		return 0;
861 	} else {
862 		ksi.ksi_signo = signo;
863 	}
864 
865 	kpsignal2(t, &ksi);
866 	return 0;
867 }
868 
869 static int
870 ptrace_dumpcore(struct lwp *lt, char *path, size_t len)
871 {
872 	int error;
873 	if (path != NULL) {
874 
875 		if (len >= MAXPATHLEN)
876 			return EINVAL;
877 
878 		char *src = path;
879 		path = kmem_alloc(len + 1, KM_SLEEP);
880 		error = copyin(src, path, len);
881 		if (error)
882 			goto out;
883 		path[len] = '\0';
884 	}
885 	error = (*coredump_vec)(lt, path);
886 out:
887 	if (path)
888 		kmem_free(path, len + 1);
889 	return error;
890 }
891 
892 static int
893 ptrace_doio(struct lwp *l, struct proc *t, struct lwp *lt,
894     struct ptrace_io_desc *piod, void *addr, bool sysspace)
895 {
896 	struct uio uio;
897 	struct iovec iov;
898 	int error, tmp;
899 
900 	error = 0;
901 	iov.iov_base = piod->piod_addr;
902 	iov.iov_len = piod->piod_len;
903 	uio.uio_iov = &iov;
904 	uio.uio_iovcnt = 1;
905 	uio.uio_offset = (off_t)(unsigned long)piod->piod_offs;
906 	uio.uio_resid = piod->piod_len;
907 
908 	switch (piod->piod_op) {
909 	case PIOD_READ_D:
910 	case PIOD_READ_I:
911 		uio.uio_rw = UIO_READ;
912 		break;
913 	case PIOD_WRITE_D:
914 	case PIOD_WRITE_I:
915 		/*
916 		 * Can't write to a RAS
917 		 */
918 		if (ras_lookup(t, addr) != (void *)-1) {
919 			return EACCES;
920 		}
921 		uio.uio_rw = UIO_WRITE;
922 		break;
923 	case PIOD_READ_AUXV:
924 		uio.uio_rw = UIO_READ;
925 		tmp = t->p_execsw->es_arglen;
926 		if (uio.uio_offset > tmp)
927 			return EIO;
928 		if (uio.uio_resid > tmp - uio.uio_offset)
929 			uio.uio_resid = tmp - uio.uio_offset;
930 		piod->piod_len = iov.iov_len = uio.uio_resid;
931 		error = process_auxv_offset(t, &uio);
932 		break;
933 	default:
934 		error = EINVAL;
935 		break;
936 	}
937 
938 	if (error)
939 		return error;
940 
941 	if (sysspace) {
942 		uio.uio_vmspace = vmspace_kernel();
943 	} else {
944 		error = proc_vmspace_getref(l->l_proc, &uio.uio_vmspace);
945 		if (error)
946 			return error;
947 	}
948 
949 	error = process_domem(l, lt, &uio);
950 	if (!sysspace)
951 		uvmspace_free(uio.uio_vmspace);
952 	if (error)
953 		return error;
954 	piod->piod_len -= uio.uio_resid;
955 	return 0;
956 }
957 
958 int
959 do_ptrace(struct ptrace_methods *ptm, struct lwp *l, int req, pid_t pid,
960     void *addr, int data, register_t *retval)
961 {
962 	struct proc *p = l->l_proc;
963 	struct lwp *lt = NULL;
964 	struct lwp *lt2;
965 	struct proc *t;				/* target process */
966 	struct ptrace_io_desc piod;
967 	int error, write, tmp, pheld;
968 	int signo = 0;
969 	int resume_all;
970 	error = 0;
971 
972 	/*
973 	 * If attaching or detaching, we need to get a write hold on the
974 	 * proclist lock so that we can re-parent the target process.
975 	 */
976 	mutex_enter(proc_lock);
977 
978 	t = ptrace_find(l, req, pid);
979 	if (t == NULL) {
980 		mutex_exit(proc_lock);
981 		return ESRCH;
982 	}
983 
984 	pheld = 1;
985 	if ((error = ptrace_allowed(l, req, t, p)) != 0)
986 		goto out;
987 
988 	if ((error = kauth_authorize_process(l->l_cred,
989 	    KAUTH_PROCESS_PTRACE, t, KAUTH_ARG(req), NULL, NULL)) != 0)
990 		goto out;
991 
992 	if ((lt = lwp_find_first(t)) == NULL) {
993 	    error = ESRCH;
994 	    goto out;
995 	}
996 
997 	/* Do single-step fixup if needed. */
998 	FIX_SSTEP(t);
999 	KASSERT(lt != NULL);
1000 	lwp_addref(lt);
1001 
1002 	/*
1003 	 * Which locks do we need held? XXX Ugly.
1004 	 */
1005 	if ((pheld = ptrace_needs_hold(req)) == 0) {
1006 		mutex_exit(t->p_lock);
1007 		mutex_exit(proc_lock);
1008 	}
1009 
1010 	/* Now do the operation. */
1011 	write = 0;
1012 	*retval = 0;
1013 	tmp = 0;
1014 	resume_all = 1;
1015 
1016 	switch (req) {
1017 	case PT_TRACE_ME:
1018 		/* Just set the trace flag. */
1019 		SET(t->p_slflag, PSL_TRACED);
1020 		t->p_opptr = t->p_pptr;
1021 		break;
1022 
1023 	case PT_WRITE_I:		/* XXX no separate I and D spaces */
1024 	case PT_WRITE_D:
1025 		write = 1;
1026 		tmp = data;
1027 		/* FALLTHROUGH */
1028 	case PT_READ_I:			/* XXX no separate I and D spaces */
1029 	case PT_READ_D:
1030 		piod.piod_addr = &tmp;
1031 		piod.piod_len = sizeof(tmp);
1032 		piod.piod_offs = addr;
1033 		piod.piod_op = write ? PIOD_WRITE_D : PIOD_READ_D;
1034 		if ((error = ptrace_doio(l, t, lt, &piod, addr, true)) != 0)
1035 			break;
1036 		if (!write)
1037 			*retval = tmp;
1038 		break;
1039 
1040 	case PT_IO:
1041 		if ((error = ptm->ptm_copyin_piod(&piod, addr, data)) != 0)
1042 			break;
1043 		if ((error = ptrace_doio(l, t, lt, &piod, addr, false)) != 0)
1044 			break;
1045 		error = ptm->ptm_copyout_piod(&piod, addr, data);
1046 		break;
1047 
1048 	case PT_DUMPCORE:
1049 		error = ptrace_dumpcore(lt, addr, data);
1050 		break;
1051 
1052 #ifdef PT_STEP
1053 	case PT_STEP:
1054 		/*
1055 		 * From the 4.4BSD PRM:
1056 		 * "Execution continues as in request PT_CONTINUE; however
1057 		 * as soon as possible after execution of at least one
1058 		 * instruction, execution stops again. [ ... ]"
1059 		 */
1060 #endif
1061 	case PT_CONTINUE:
1062 	case PT_SYSCALL:
1063 	case PT_DETACH:
1064 		if (req == PT_SYSCALL) {
1065 			if (!ISSET(t->p_slflag, PSL_SYSCALL)) {
1066 				SET(t->p_slflag, PSL_SYSCALL);
1067 #ifdef __HAVE_SYSCALL_INTERN
1068 				(*t->p_emul->e_syscall_intern)(t);
1069 #endif
1070 			}
1071 		} else {
1072 			if (ISSET(t->p_slflag, PSL_SYSCALL)) {
1073 				CLR(t->p_slflag, PSL_SYSCALL);
1074 #ifdef __HAVE_SYSCALL_INTERN
1075 				(*t->p_emul->e_syscall_intern)(t);
1076 #endif
1077 			}
1078 		}
1079 		t->p_trace_enabled = trace_is_enabled(t);
1080 
1081 		/*
1082 		 * Pick up the LWPID, if supplied.  There are two cases:
1083 		 * data < 0 : step or continue single thread, lwp = -data
1084 		 * data > 0 in PT_STEP : step this thread, continue others
1085 		 * For operations other than PT_STEP, data > 0 means
1086 		 * data is the signo to deliver to the process.
1087 		 */
1088 		tmp = data;
1089 		if (tmp >= 0) {
1090 #ifdef PT_STEP
1091 			if (req == PT_STEP)
1092 				signo = 0;
1093 			else
1094 #endif
1095 			{
1096 				signo = tmp;
1097 				tmp = 0;	/* don't search for LWP */
1098 			}
1099 		} else
1100 			tmp = -tmp;
1101 
1102 		if (tmp > 0) {
1103 			if (req == PT_DETACH) {
1104 				error = EINVAL;
1105 				break;
1106 			}
1107 			lwp_delref2 (lt);
1108 			lt = lwp_find(t, tmp);
1109 			if (lt == NULL) {
1110 				error = ESRCH;
1111 				break;
1112 			}
1113 			lwp_addref(lt);
1114 			resume_all = 0;
1115 			signo = 0;
1116 		}
1117 
1118 		/*
1119 		 * From the 4.4BSD PRM:
1120 		 * "The data argument is taken as a signal number and the
1121 		 * child's execution continues at location addr as if it
1122 		 * incurred that signal.  Normally the signal number will
1123 		 * be either 0 to indicate that the signal that caused the
1124 		 * stop should be ignored, or that value fetched out of
1125 		 * the process's image indicating which signal caused
1126 		 * the stop.  If addr is (int *)1 then execution continues
1127 		 * from where it stopped."
1128 		 */
1129 
1130 		/* Check that the data is a valid signal number or zero. */
1131 		if (signo < 0 || signo >= NSIG) {
1132 			error = EINVAL;
1133 			break;
1134 		}
1135 
1136 		/* Prevent process deadlock */
1137 		if (resume_all) {
1138 #ifdef PT_STEP
1139 			if (req == PT_STEP) {
1140 				if (lt->l_flag & LW_WSUSPEND) {
1141 					error = EDEADLK;
1142 					break;
1143 				}
1144 			} else
1145 #endif
1146 			{
1147 				error = EDEADLK;
1148 				LIST_FOREACH(lt2, &t->p_lwps, l_sibling) {
1149 					if ((lt2->l_flag & LW_WSUSPEND) == 0) {
1150 						error = 0;
1151 						break;
1152 					}
1153 				}
1154 				if (error != 0)
1155 					break;
1156 			}
1157 		} else {
1158 			if (lt->l_flag & LW_WSUSPEND) {
1159 				error = EDEADLK;
1160 				break;
1161 			}
1162 		}
1163 
1164 		/* If the address parameter is not (int *)1, set the pc. */
1165 		if ((int *)addr != (int *)1) {
1166 			error = process_set_pc(lt, addr);
1167 			if (error != 0)
1168 				break;
1169 		}
1170 #ifdef PT_STEP
1171 		/*
1172 		 * Arrange for a single-step, if that's requested and possible.
1173 		 * More precisely, set the single step status as requested for
1174 		 * the requested thread, and clear it for other threads.
1175 		 */
1176 		LIST_FOREACH(lt2, &t->p_lwps, l_sibling) {
1177 			if (ISSET(lt2->l_pflag, LP_SINGLESTEP)) {
1178 				lwp_lock(lt2);
1179 				process_sstep(lt2, 1);
1180 				lwp_unlock(lt2);
1181 			} else if (lt != lt2) {
1182 				lwp_lock(lt2);
1183 				process_sstep(lt2, 0);
1184 				lwp_unlock(lt2);
1185 			}
1186 		}
1187 		error = process_sstep(lt,
1188 		    ISSET(lt->l_pflag, LP_SINGLESTEP) || req == PT_STEP);
1189 		if (error)
1190 			break;
1191 #endif
1192 		if (req == PT_DETACH) {
1193 			CLR(t->p_slflag, PSL_TRACED|PSL_SYSCALL);
1194 
1195 			/* give process back to original parent or init */
1196 			if (t->p_opptr != t->p_pptr) {
1197 				struct proc *pp = t->p_opptr;
1198 				proc_reparent(t, pp ? pp : initproc);
1199 			}
1200 
1201 			/* not being traced any more */
1202 			t->p_opptr = NULL;
1203 
1204 			/* clear single step */
1205 			LIST_FOREACH(lt2, &t->p_lwps, l_sibling) {
1206 				CLR(lt2->l_pflag, LP_SINGLESTEP);
1207 			}
1208 			CLR(lt->l_pflag, LP_SINGLESTEP);
1209 		}
1210 	sendsig:
1211 		error = ptrace_sendsig(t, lt, signo, resume_all);
1212 		break;
1213 
1214 	case PT_SYSCALLEMU:
1215 		if (!ISSET(t->p_slflag, PSL_SYSCALL) || t->p_stat != SSTOP) {
1216 			error = EINVAL;
1217 			break;
1218 		}
1219 		SET(t->p_slflag, PSL_SYSCALLEMU);
1220 		break;
1221 
1222 #ifdef PT_STEP
1223 	case PT_SETSTEP:
1224 		write = 1;
1225 
1226 	case PT_CLEARSTEP:
1227 		/* write = 0 done above. */
1228 		if ((error = ptrace_update_lwp(t, &lt, data)) != 0)
1229 			break;
1230 
1231 		if (write)
1232 			SET(lt->l_pflag, LP_SINGLESTEP);
1233 		else
1234 			CLR(lt->l_pflag, LP_SINGLESTEP);
1235 		break;
1236 #endif
1237 
1238 	case PT_KILL:
1239 		/* just send the process a KILL signal. */
1240 		signo = SIGKILL;
1241 		goto sendsig;	/* in PT_CONTINUE, above. */
1242 
1243 	case PT_ATTACH:
1244 		/*
1245 		 * Go ahead and set the trace flag.
1246 		 * Save the old parent (it's reset in
1247 		 *   _DETACH, and also in kern_exit.c:wait4()
1248 		 * Reparent the process so that the tracing
1249 		 *   proc gets to see all the action.
1250 		 * Stop the target.
1251 		 */
1252 		proc_changeparent(t, p);
1253 		signo = SIGSTOP;
1254 		goto sendsig;
1255 
1256 	case PT_GET_EVENT_MASK:
1257 		error = ptrace_get_event_mask(t, addr, data);
1258 		break;
1259 
1260 	case PT_SET_EVENT_MASK:
1261 		error = ptrace_set_event_mask(t, addr, data);
1262 		break;
1263 
1264 	case PT_GET_PROCESS_STATE:
1265 		error = ptrace_get_process_state(t, addr, data);
1266 		break;
1267 
1268 	case PT_LWPINFO:
1269 		error = ptrace_lwpinfo(t, &lt, addr, data);
1270 		break;
1271 
1272 	case PT_SET_SIGINFO:
1273 		error = ptrace_set_siginfo(t, &lt, ptm, addr, data);
1274 		break;
1275 
1276 	case PT_GET_SIGINFO:
1277 		error = ptrace_get_siginfo(t, ptm, addr, data);
1278 		break;
1279 
1280 	case PT_RESUME:
1281 	case PT_SUSPEND:
1282 		error = ptrace_startstop(t, &lt, req, addr, data);
1283 		break;
1284 
1285 #ifdef PT_REGISTERS
1286 	case_PT_SETREGS
1287 	case_PT_GETREGS
1288 	case_PT_SETFPREGS
1289 	case_PT_GETFPREGS
1290 	case_PT_SETDBREGS
1291 	case_PT_GETDBREGS
1292 		error = ptrace_regs(l, &lt, req, ptm, addr, data);
1293 		break;
1294 #endif
1295 
1296 #ifdef __HAVE_PTRACE_MACHDEP
1297 	PTRACE_MACHDEP_REQUEST_CASES
1298 		error = ptrace_machdep_dorequest(l, lt, req, addr, data);
1299 		break;
1300 #endif
1301 	}
1302 
1303 out:
1304 	if (pheld) {
1305 		mutex_exit(t->p_lock);
1306 		mutex_exit(proc_lock);
1307 	}
1308 	if (lt != NULL)
1309 		lwp_delref(lt);
1310 	rw_exit(&t->p_reflock);
1311 
1312 	return error;
1313 }
1314 
1315 typedef int (*regrfunc_t)(struct lwp *, void *, size_t *);
1316 typedef int (*regwfunc_t)(struct lwp *, void *, size_t);
1317 
1318 #ifdef PT_REGISTERS
1319 static int
1320 proc_regio(struct lwp *l, struct uio *uio, size_t ks, regrfunc_t r,
1321     regwfunc_t w)
1322 {
1323 	char buf[1024];
1324 	int error;
1325 	char *kv;
1326 	size_t kl;
1327 
1328 	if (ks > sizeof(buf))
1329 		return E2BIG;
1330 
1331 	if (uio->uio_offset < 0 || uio->uio_offset > (off_t)ks)
1332 		return EINVAL;
1333 
1334 	kv = buf + uio->uio_offset;
1335 	kl = ks - uio->uio_offset;
1336 
1337 	if (kl > uio->uio_resid)
1338 		kl = uio->uio_resid;
1339 
1340 	error = (*r)(l, buf, &ks);
1341 	if (error == 0)
1342 		error = uiomove(kv, kl, uio);
1343 	if (error == 0 && uio->uio_rw == UIO_WRITE) {
1344 		if (l->l_stat != LSSTOP)
1345 			error = EBUSY;
1346 		else
1347 			error = (*w)(l, buf, ks);
1348 	}
1349 
1350 	uio->uio_offset = 0;
1351 	return error;
1352 }
1353 #endif
1354 
1355 int
1356 process_doregs(struct lwp *curl /*tracer*/,
1357     struct lwp *l /*traced*/,
1358     struct uio *uio)
1359 {
1360 #if defined(PT_GETREGS) || defined(PT_SETREGS)
1361 	size_t s;
1362 	regrfunc_t r;
1363 	regwfunc_t w;
1364 
1365 #ifdef COMPAT_NETBSD32
1366 	const bool pk32 = (l->l_proc->p_flag & PK_32) != 0;
1367 
1368 	if (__predict_false(pk32)) {
1369 		s = sizeof(process_reg32);
1370 		r = (regrfunc_t)process_read_regs32;
1371 		w = (regwfunc_t)process_write_regs32;
1372 	} else
1373 #endif
1374 	{
1375 		s = sizeof(struct reg);
1376 		r = (regrfunc_t)process_read_regs;
1377 		w = (regwfunc_t)process_write_regs;
1378 	}
1379 	return proc_regio(l, uio, s, r, w);
1380 #else
1381 	return EINVAL;
1382 #endif
1383 }
1384 
1385 int
1386 process_validregs(struct lwp *l)
1387 {
1388 
1389 #if defined(PT_SETREGS) || defined(PT_GETREGS)
1390 	return (l->l_flag & LW_SYSTEM) == 0;
1391 #else
1392 	return 0;
1393 #endif
1394 }
1395 
1396 int
1397 process_dofpregs(struct lwp *curl /*tracer*/,
1398     struct lwp *l /*traced*/,
1399     struct uio *uio)
1400 {
1401 #if defined(PT_GETFPREGS) || defined(PT_SETFPREGS)
1402 	size_t s;
1403 	regrfunc_t r;
1404 	regwfunc_t w;
1405 
1406 #ifdef COMPAT_NETBSD32
1407 	const bool pk32 = (l->l_proc->p_flag & PK_32) != 0;
1408 
1409 	if (__predict_false(pk32)) {
1410 		s = sizeof(process_fpreg32);
1411 		r = (regrfunc_t)process_read_fpregs32;
1412 		w = (regwfunc_t)process_write_fpregs32;
1413 	} else
1414 #endif
1415 	{
1416 		s = sizeof(struct fpreg);
1417 		r = (regrfunc_t)process_read_fpregs;
1418 		w = (regwfunc_t)process_write_fpregs;
1419 	}
1420 	return proc_regio(l, uio, s, r, w);
1421 #else
1422 	return EINVAL;
1423 #endif
1424 }
1425 
1426 int
1427 process_validfpregs(struct lwp *l)
1428 {
1429 
1430 #if defined(PT_SETFPREGS) || defined(PT_GETFPREGS)
1431 	return (l->l_flag & LW_SYSTEM) == 0;
1432 #else
1433 	return 0;
1434 #endif
1435 }
1436 
1437 int
1438 process_dodbregs(struct lwp *curl /*tracer*/,
1439     struct lwp *l /*traced*/,
1440     struct uio *uio)
1441 {
1442 #if defined(PT_GETDBREGS) || defined(PT_SETDBREGS)
1443 	size_t s;
1444 	regrfunc_t r;
1445 	regwfunc_t w;
1446 
1447 #ifdef COMPAT_NETBSD32
1448 	const bool pk32 = (l->l_proc->p_flag & PK_32) != 0;
1449 
1450 	if (__predict_false(pk32)) {
1451 		s = sizeof(process_dbreg32);
1452 		r = (regrfunc_t)process_read_dbregs32;
1453 		w = (regwfunc_t)process_write_dbregs32;
1454 	} else
1455 #endif
1456 	{
1457 		s = sizeof(struct dbreg);
1458 		r = (regrfunc_t)process_read_dbregs;
1459 		w = (regwfunc_t)process_write_dbregs;
1460 	}
1461 	return proc_regio(l, uio, s, r, w);
1462 #else
1463 	return EINVAL;
1464 #endif
1465 }
1466 
1467 int
1468 process_validdbregs(struct lwp *l)
1469 {
1470 
1471 #if defined(PT_SETDBREGS) || defined(PT_GETDBREGS)
1472 	return (l->l_flag & LW_SYSTEM) == 0;
1473 #else
1474 	return 0;
1475 #endif
1476 }
1477 
1478 static int
1479 process_auxv_offset(struct proc *p, struct uio *uio)
1480 {
1481 	struct ps_strings pss;
1482 	int error;
1483 	off_t off = (off_t)p->p_psstrp;
1484 
1485 	if ((error = copyin_psstrings(p, &pss)) != 0)
1486 		return error;
1487 
1488 	if (pss.ps_envstr == NULL)
1489 		return EIO;
1490 
1491 	uio->uio_offset += (off_t)(vaddr_t)(pss.ps_envstr + pss.ps_nenvstr + 1);
1492 #ifdef __MACHINE_STACK_GROWS_UP
1493 	if (uio->uio_offset < off)
1494 		return EIO;
1495 #else
1496 	if (uio->uio_offset > off)
1497 		return EIO;
1498 	if ((uio->uio_offset + uio->uio_resid) > off)
1499 		uio->uio_resid = off - uio->uio_offset;
1500 #endif
1501 	return 0;
1502 }
1503 #endif /* PTRACE */
1504 
1505 MODULE(MODULE_CLASS_EXEC, ptrace_common, "");
1506 
1507 static int
1508 ptrace_common_modcmd(modcmd_t cmd, void *arg)
1509 {
1510         int error;
1511 
1512         switch (cmd) {
1513         case MODULE_CMD_INIT:
1514                 error = ptrace_init();
1515                 break;
1516         case MODULE_CMD_FINI:
1517                 error = ptrace_fini();
1518                 break;
1519         default:
1520 		ptrace_hooks();
1521                 error = ENOTTY;
1522                 break;
1523         }
1524         return error;
1525 }
1526