1/*-
2 * Implementation of SVID messages
3 *
4 * Author:  Daniel Boulet
5 *
6 * Copyright 1993 Daniel Boulet and RTMX Inc.
7 *
8 * This system call was implemented by Daniel Boulet under contract from RTMX.
9 *
10 * Redistribution and use in source forms, with and without modification,
11 * are permitted provided that this entire comment appears intact.
12 *
13 * Redistribution in binary form may occur without any restrictions.
14 * Obviously, it would be nice if you gave credit where credit is due
15 * but requiring it would be too onerous.
16 *
17 * This software is provided ``AS IS'' without any warranties of any kind.
18 */
19/*-
20 * SPDX-License-Identifier: BSD-2-Clause-FreeBSD
21 *
22 * Copyright (c) 2003-2005 McAfee, Inc.
23 * Copyright (c) 2016-2017 Robert N. M. Watson
24 * All rights reserved.
25 *
26 * This software was developed for the FreeBSD Project in part by McAfee
27 * Research, the Security Research Division of McAfee, Inc under DARPA/SPAWAR
28 * contract N66001-01-C-8035 ("CBOSS"), as part of the DARPA CHATS research
29 * program.
30 *
31 * Portions of this software were developed by BAE Systems, the University of
32 * Cambridge Computer Laboratory, and Memorial University under DARPA/AFRL
33 * contract FA8650-15-C-7558 ("CADETS"), as part of the DARPA Transparent
34 * Computing (TC) research program.
35 *
36 * Redistribution and use in source and binary forms, with or without
37 * modification, are permitted provided that the following conditions
38 * are met:
39 * 1. Redistributions of source code must retain the above copyright
40 *    notice, this list of conditions and the following disclaimer.
41 * 2. Redistributions in binary form must reproduce the above copyright
42 *    notice, this list of conditions and the following disclaimer in the
43 *    documentation and/or other materials provided with the distribution.
44 *
45 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
46 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
47 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
48 * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
49 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
50 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
51 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
52 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
53 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
54 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
55 * SUCH DAMAGE.
56 */
57
58#include <sys/cdefs.h>
59__FBSDID("$FreeBSD$");
60
61#include "opt_sysvipc.h"
62
63#include <sys/param.h>
64#include <sys/systm.h>
65#include <sys/sysproto.h>
66#include <sys/kernel.h>
67#include <sys/priv.h>
68#include <sys/proc.h>
69#include <sys/lock.h>
70#include <sys/mutex.h>
71#include <sys/module.h>
72#include <sys/mount.h>
73#include <sys/msg.h>
74#include <sys/racct.h>
75#include <sys/sx.h>
76#include <sys/syscall.h>
77#include <sys/syscallsubr.h>
78#include <sys/sysent.h>
79#include <sys/sysctl.h>
80#include <sys/malloc.h>
81#include <sys/jail.h>
82
83#include <security/audit/audit.h>
84#include <security/mac/mac_framework.h>
85
86FEATURE(sysv_msg, "System V message queues support");
87
88static MALLOC_DEFINE(M_MSG, "msg", "SVID compatible message queues");
89
90static int msginit(void);
91static int msgunload(void);
92static int sysvmsg_modload(struct module *, int, void *);
93static void msq_remove(struct msqid_kernel *);
94static struct prison *msg_find_prison(struct ucred *);
95static int msq_prison_cansee(struct prison *, struct msqid_kernel *);
96static int msg_prison_check(void *, void *);
97static int msg_prison_set(void *, void *);
98static int msg_prison_get(void *, void *);
99static int msg_prison_remove(void *, void *);
100static void msg_prison_cleanup(struct prison *);
101
102
103#ifdef MSG_DEBUG
104#define DPRINTF(a)	printf a
105#else
106#define DPRINTF(a)	(void)0
107#endif
108
109static void msg_freehdr(struct msg *msghdr);
110
111#ifndef MSGSSZ
112#define MSGSSZ	8		/* Each segment must be 2^N long */
113#endif
114#ifndef MSGSEG
115#define MSGSEG	2048		/* must be less than 32767 */
116#endif
117#define MSGMAX	(MSGSSZ*MSGSEG)
118#ifndef MSGMNB
119#define MSGMNB	2048		/* max # of bytes in a queue */
120#endif
121#ifndef MSGMNI
122#define MSGMNI	40
123#endif
124#ifndef MSGTQL
125#define MSGTQL	40
126#endif
127
128/*
129 * Based on the configuration parameters described in an SVR2 (yes, two)
130 * config(1m) man page.
131 *
132 * Each message is broken up and stored in segments that are msgssz bytes
133 * long.  For efficiency reasons, this should be a power of two.  Also,
134 * it doesn't make sense if it is less than 8 or greater than about 256.
135 * Consequently, msginit in kern/sysv_msg.c checks that msgssz is a power of
136 * two between 8 and 1024 inclusive (and panic's if it isn't).
137 */
138struct msginfo msginfo = {
139                MSGMAX,         /* max chars in a message */
140                MSGMNI,         /* # of message queue identifiers */
141                MSGMNB,         /* max chars in a queue */
142                MSGTQL,         /* max messages in system */
143                MSGSSZ,         /* size of a message segment */
144                		/* (must be small power of 2 greater than 4) */
145                MSGSEG          /* number of message segments */
146};
147
148/*
149 * macros to convert between msqid_ds's and msqid's.
150 * (specific to this implementation)
151 */
152#define MSQID(ix,ds)	((ix) & 0xffff | (((ds).msg_perm.seq << 16) & 0xffff0000))
153#define MSQID_IX(id)	((id) & 0xffff)
154#define MSQID_SEQ(id)	(((id) >> 16) & 0xffff)
155
156/*
157 * The rest of this file is specific to this particular implementation.
158 */
159
160struct msgmap {
161	short	next;		/* next segment in buffer */
162    				/* -1 -> available */
163    				/* 0..(MSGSEG-1) -> index of next segment */
164};
165
166#define MSG_LOCKED	01000	/* Is this msqid_ds locked? */
167
168static int nfree_msgmaps;	/* # of free map entries */
169static short free_msgmaps;	/* head of linked list of free map entries */
170static struct msg *free_msghdrs;/* list of free msg headers */
171static char *msgpool;		/* MSGMAX byte long msg buffer pool */
172static struct msgmap *msgmaps;	/* MSGSEG msgmap structures */
173static struct msg *msghdrs;	/* MSGTQL msg headers */
174static struct msqid_kernel *msqids;	/* MSGMNI msqid_kernel struct's */
175static struct mtx msq_mtx;	/* global mutex for message queues. */
176static unsigned msg_prison_slot;/* prison OSD slot */
177
178static struct syscall_helper_data msg_syscalls[] = {
179	SYSCALL_INIT_HELPER(msgctl),
180	SYSCALL_INIT_HELPER(msgget),
181	SYSCALL_INIT_HELPER(msgsnd),
182	SYSCALL_INIT_HELPER(msgrcv),
183#if defined(COMPAT_FREEBSD4) || defined(COMPAT_FREEBSD5) || \
184    defined(COMPAT_FREEBSD6) || defined(COMPAT_FREEBSD7)
185	SYSCALL_INIT_HELPER(msgsys),
186	SYSCALL_INIT_HELPER_COMPAT(freebsd7_msgctl),
187#endif
188	SYSCALL_INIT_LAST
189};
190
191#ifdef COMPAT_FREEBSD32
192#include <compat/freebsd32/freebsd32.h>
193#include <compat/freebsd32/freebsd32_ipc.h>
194#include <compat/freebsd32/freebsd32_proto.h>
195#include <compat/freebsd32/freebsd32_signal.h>
196#include <compat/freebsd32/freebsd32_syscall.h>
197#include <compat/freebsd32/freebsd32_util.h>
198
199static struct syscall_helper_data msg32_syscalls[] = {
200	SYSCALL32_INIT_HELPER(freebsd32_msgctl),
201	SYSCALL32_INIT_HELPER(freebsd32_msgsnd),
202	SYSCALL32_INIT_HELPER(freebsd32_msgrcv),
203	SYSCALL32_INIT_HELPER_COMPAT(msgget),
204	SYSCALL32_INIT_HELPER(freebsd32_msgsys),
205#if defined(COMPAT_FREEBSD4) || defined(COMPAT_FREEBSD5) || \
206    defined(COMPAT_FREEBSD6) || defined(COMPAT_FREEBSD7)
207	SYSCALL32_INIT_HELPER(freebsd7_freebsd32_msgctl),
208#endif
209	SYSCALL_INIT_LAST
210};
211#endif
212
213static int
214msginit()
215{
216	struct prison *pr;
217	void **rsv;
218	int i, error;
219	osd_method_t methods[PR_MAXMETHOD] = {
220	    [PR_METHOD_CHECK] =		msg_prison_check,
221	    [PR_METHOD_SET] =		msg_prison_set,
222	    [PR_METHOD_GET] =		msg_prison_get,
223	    [PR_METHOD_REMOVE] =	msg_prison_remove,
224	};
225
226	msginfo.msgmax = msginfo.msgseg * msginfo.msgssz;
227	msgpool = malloc(msginfo.msgmax, M_MSG, M_WAITOK);
228	msgmaps = malloc(sizeof(struct msgmap) * msginfo.msgseg, M_MSG, M_WAITOK);
229	msghdrs = malloc(sizeof(struct msg) * msginfo.msgtql, M_MSG, M_WAITOK);
230	msqids = malloc(sizeof(struct msqid_kernel) * msginfo.msgmni, M_MSG,
231	    M_WAITOK | M_ZERO);
232
233	/*
234	 * msginfo.msgssz should be a power of two for efficiency reasons.
235	 * It is also pretty silly if msginfo.msgssz is less than 8
236	 * or greater than about 256 so ...
237	 */
238
239	i = 8;
240	while (i < 1024 && i != msginfo.msgssz)
241		i <<= 1;
242    	if (i != msginfo.msgssz) {
243		DPRINTF(("msginfo.msgssz=%d (0x%x)\n", msginfo.msgssz,
244		    msginfo.msgssz));
245		panic("msginfo.msgssz not a small power of 2");
246	}
247
248	if (msginfo.msgseg > 32767) {
249		DPRINTF(("msginfo.msgseg=%d\n", msginfo.msgseg));
250		panic("msginfo.msgseg > 32767");
251	}
252
253	for (i = 0; i < msginfo.msgseg; i++) {
254		if (i > 0)
255			msgmaps[i-1].next = i;
256		msgmaps[i].next = -1;	/* implies entry is available */
257	}
258	free_msgmaps = 0;
259	nfree_msgmaps = msginfo.msgseg;
260
261	for (i = 0; i < msginfo.msgtql; i++) {
262		msghdrs[i].msg_type = 0;
263		if (i > 0)
264			msghdrs[i-1].msg_next = &msghdrs[i];
265		msghdrs[i].msg_next = NULL;
266#ifdef MAC
267		mac_sysvmsg_init(&msghdrs[i]);
268#endif
269    	}
270	free_msghdrs = &msghdrs[0];
271
272	for (i = 0; i < msginfo.msgmni; i++) {
273		msqids[i].u.msg_qbytes = 0;	/* implies entry is available */
274		msqids[i].u.msg_perm.seq = 0;	/* reset to a known value */
275		msqids[i].u.msg_perm.mode = 0;
276#ifdef MAC
277		mac_sysvmsq_init(&msqids[i]);
278#endif
279	}
280	mtx_init(&msq_mtx, "msq", NULL, MTX_DEF);
281
282	/* Set current prisons according to their allow.sysvipc. */
283	msg_prison_slot = osd_jail_register(NULL, methods);
284	rsv = osd_reserve(msg_prison_slot);
285	prison_lock(&prison0);
286	(void)osd_jail_set_reserved(&prison0, msg_prison_slot, rsv, &prison0);
287	prison_unlock(&prison0);
288	rsv = NULL;
289	sx_slock(&allprison_lock);
290	TAILQ_FOREACH(pr, &allprison, pr_list) {
291		if (rsv == NULL)
292			rsv = osd_reserve(msg_prison_slot);
293		prison_lock(pr);
294		if ((pr->pr_allow & PR_ALLOW_SYSVIPC) && pr->pr_ref > 0) {
295			(void)osd_jail_set_reserved(pr, msg_prison_slot, rsv,
296			    &prison0);
297			rsv = NULL;
298		}
299		prison_unlock(pr);
300	}
301	if (rsv != NULL)
302		osd_free_reserved(rsv);
303	sx_sunlock(&allprison_lock);
304
305	error = syscall_helper_register(msg_syscalls, SY_THR_STATIC_KLD);
306	if (error != 0)
307		return (error);
308#ifdef COMPAT_FREEBSD32
309	error = syscall32_helper_register(msg32_syscalls, SY_THR_STATIC_KLD);
310	if (error != 0)
311		return (error);
312#endif
313	return (0);
314}
315
316static int
317msgunload()
318{
319	struct msqid_kernel *msqkptr;
320	int msqid;
321#ifdef MAC
322	int i;
323#endif
324
325	syscall_helper_unregister(msg_syscalls);
326#ifdef COMPAT_FREEBSD32
327	syscall32_helper_unregister(msg32_syscalls);
328#endif
329
330	for (msqid = 0; msqid < msginfo.msgmni; msqid++) {
331		msqkptr = &msqids[msqid];
332		if (msqkptr->u.msg_qbytes != 0 ||
333		    (msqkptr->u.msg_perm.mode & MSG_LOCKED) != 0)
334			break;
335	}
336	if (msqid != msginfo.msgmni)
337		return (EBUSY);
338
339	if (msg_prison_slot != 0)
340		osd_jail_deregister(msg_prison_slot);
341#ifdef MAC
342	for (i = 0; i < msginfo.msgtql; i++)
343		mac_sysvmsg_destroy(&msghdrs[i]);
344	for (msqid = 0; msqid < msginfo.msgmni; msqid++)
345		mac_sysvmsq_destroy(&msqids[msqid]);
346#endif
347	free(msgpool, M_MSG);
348	free(msgmaps, M_MSG);
349	free(msghdrs, M_MSG);
350	free(msqids, M_MSG);
351	mtx_destroy(&msq_mtx);
352	return (0);
353}
354
355
356static int
357sysvmsg_modload(struct module *module, int cmd, void *arg)
358{
359	int error = 0;
360
361	switch (cmd) {
362	case MOD_LOAD:
363		error = msginit();
364		if (error != 0)
365			msgunload();
366		break;
367	case MOD_UNLOAD:
368		error = msgunload();
369		break;
370	case MOD_SHUTDOWN:
371		break;
372	default:
373		error = EINVAL;
374		break;
375	}
376	return (error);
377}
378
379static moduledata_t sysvmsg_mod = {
380	"sysvmsg",
381	&sysvmsg_modload,
382	NULL
383};
384
385DECLARE_MODULE(sysvmsg, sysvmsg_mod, SI_SUB_SYSV_MSG, SI_ORDER_FIRST);
386MODULE_VERSION(sysvmsg, 1);
387
388static void
389msg_freehdr(struct msg *msghdr)
390{
391	while (msghdr->msg_ts > 0) {
392		short next;
393		if (msghdr->msg_spot < 0 || msghdr->msg_spot >= msginfo.msgseg)
394			panic("msghdr->msg_spot out of range");
395		next = msgmaps[msghdr->msg_spot].next;
396		msgmaps[msghdr->msg_spot].next = free_msgmaps;
397		free_msgmaps = msghdr->msg_spot;
398		nfree_msgmaps++;
399		msghdr->msg_spot = next;
400		if (msghdr->msg_ts >= msginfo.msgssz)
401			msghdr->msg_ts -= msginfo.msgssz;
402		else
403			msghdr->msg_ts = 0;
404	}
405	if (msghdr->msg_spot != -1)
406		panic("msghdr->msg_spot != -1");
407	msghdr->msg_next = free_msghdrs;
408	free_msghdrs = msghdr;
409#ifdef MAC
410	mac_sysvmsg_cleanup(msghdr);
411#endif
412}
413
414static void
415msq_remove(struct msqid_kernel *msqkptr)
416{
417	struct msg *msghdr;
418
419	racct_sub_cred(msqkptr->cred, RACCT_NMSGQ, 1);
420	racct_sub_cred(msqkptr->cred, RACCT_MSGQQUEUED, msqkptr->u.msg_qnum);
421	racct_sub_cred(msqkptr->cred, RACCT_MSGQSIZE, msqkptr->u.msg_cbytes);
422	crfree(msqkptr->cred);
423	msqkptr->cred = NULL;
424
425	/* Free the message headers */
426	msghdr = msqkptr->u.__msg_first;
427	while (msghdr != NULL) {
428		struct msg *msghdr_tmp;
429
430		/* Free the segments of each message */
431		msqkptr->u.msg_cbytes -= msghdr->msg_ts;
432		msqkptr->u.msg_qnum--;
433		msghdr_tmp = msghdr;
434		msghdr = msghdr->msg_next;
435		msg_freehdr(msghdr_tmp);
436	}
437
438	if (msqkptr->u.msg_cbytes != 0)
439		panic("msg_cbytes is screwed up");
440	if (msqkptr->u.msg_qnum != 0)
441		panic("msg_qnum is screwed up");
442
443	msqkptr->u.msg_qbytes = 0;	/* Mark it as free */
444
445#ifdef MAC
446	mac_sysvmsq_cleanup(msqkptr);
447#endif
448
449	wakeup(msqkptr);
450}
451
452static struct prison *
453msg_find_prison(struct ucred *cred)
454{
455	struct prison *pr, *rpr;
456
457	pr = cred->cr_prison;
458	prison_lock(pr);
459	rpr = osd_jail_get(pr, msg_prison_slot);
460	prison_unlock(pr);
461	return rpr;
462}
463
464static int
465msq_prison_cansee(struct prison *rpr, struct msqid_kernel *msqkptr)
466{
467
468	if (msqkptr->cred == NULL ||
469	    !(rpr == msqkptr->cred->cr_prison ||
470	      prison_ischild(rpr, msqkptr->cred->cr_prison)))
471		return (EINVAL);
472	return (0);
473}
474
475#ifndef _SYS_SYSPROTO_H_
476struct msgctl_args {
477	int	msqid;
478	int	cmd;
479	struct	msqid_ds *buf;
480};
481#endif
482int
483sys_msgctl(struct thread *td, struct msgctl_args *uap)
484{
485	int msqid = uap->msqid;
486	int cmd = uap->cmd;
487	struct msqid_ds msqbuf;
488	int error;
489
490	DPRINTF(("call to msgctl(%d, %d, %p)\n", msqid, cmd, uap->buf));
491	if (cmd == IPC_SET &&
492	    (error = copyin(uap->buf, &msqbuf, sizeof(msqbuf))) != 0)
493		return (error);
494	error = kern_msgctl(td, msqid, cmd, &msqbuf);
495	if (cmd == IPC_STAT && error == 0)
496		error = copyout(&msqbuf, uap->buf, sizeof(struct msqid_ds));
497	return (error);
498}
499
500int
501kern_msgctl(struct thread *td, int msqid, int cmd, struct msqid_ds *msqbuf)
502{
503	int rval, error, msqix;
504	struct msqid_kernel *msqkptr;
505	struct prison *rpr;
506
507	rpr = msg_find_prison(td->td_ucred);
508	if (rpr == NULL)
509		return (ENOSYS);
510
511	AUDIT_ARG_SVIPC_CMD(cmd);
512	AUDIT_ARG_SVIPC_ID(msqid);
513	msqix = IPCID_TO_IX(msqid);
514
515	if (msqix < 0 || msqix >= msginfo.msgmni) {
516		DPRINTF(("msqid (%d) out of range (0<=msqid<%d)\n", msqix,
517		    msginfo.msgmni));
518		return (EINVAL);
519	}
520
521	msqkptr = &msqids[msqix];
522
523	mtx_lock(&msq_mtx);
524	if (msqkptr->u.msg_qbytes == 0) {
525		DPRINTF(("no such msqid\n"));
526		error = EINVAL;
527		goto done2;
528	}
529	if (msqkptr->u.msg_perm.seq != IPCID_TO_SEQ(msqid)) {
530		DPRINTF(("wrong sequence number\n"));
531		error = EINVAL;
532		goto done2;
533	}
534
535	error = msq_prison_cansee(rpr, msqkptr);
536	if (error != 0) {
537		DPRINTF(("requester can't see prison\n"));
538		goto done2;
539	}
540
541#ifdef MAC
542	error = mac_sysvmsq_check_msqctl(td->td_ucred, msqkptr, cmd);
543	if (error != 0)
544		goto done2;
545#endif
546
547	error = 0;
548	rval = 0;
549
550	switch (cmd) {
551
552	case IPC_RMID:
553	{
554#ifdef MAC
555		struct msg *msghdr;
556#endif
557		if ((error = ipcperm(td, &msqkptr->u.msg_perm, IPC_M)))
558			goto done2;
559
560#ifdef MAC
561		/*
562		 * Check that the thread has MAC access permissions to
563		 * individual msghdrs.  Note: We need to do this in a
564		 * separate loop because the actual loop alters the
565		 * msq/msghdr info as it progresses, and there is no going
566		 * back if half the way through we discover that the
567		 * thread cannot free a certain msghdr.  The msq will get
568		 * into an inconsistent state.
569		 */
570		for (msghdr = msqkptr->u.__msg_first; msghdr != NULL;
571		    msghdr = msghdr->msg_next) {
572			error = mac_sysvmsq_check_msgrmid(td->td_ucred, msghdr);
573			if (error != 0)
574				goto done2;
575		}
576#endif
577
578		msq_remove(msqkptr);
579	}
580
581		break;
582
583	case IPC_SET:
584		AUDIT_ARG_SVIPC_PERM(&msqbuf->msg_perm);
585		if ((error = ipcperm(td, &msqkptr->u.msg_perm, IPC_M)))
586			goto done2;
587		if (msqbuf->msg_qbytes > msqkptr->u.msg_qbytes) {
588			error = priv_check(td, PRIV_IPC_MSGSIZE);
589			if (error)
590				goto done2;
591		}
592		if (msqbuf->msg_qbytes > msginfo.msgmnb) {
593			DPRINTF(("can't increase msg_qbytes beyond %d"
594			    "(truncating)\n", msginfo.msgmnb));
595			msqbuf->msg_qbytes = msginfo.msgmnb;	/* silently restrict qbytes to system limit */
596		}
597		if (msqbuf->msg_qbytes == 0) {
598			DPRINTF(("can't reduce msg_qbytes to 0\n"));
599			error = EINVAL;		/* non-standard errno! */
600			goto done2;
601		}
602		msqkptr->u.msg_perm.uid = msqbuf->msg_perm.uid;	/* change the owner */
603		msqkptr->u.msg_perm.gid = msqbuf->msg_perm.gid;	/* change the owner */
604		msqkptr->u.msg_perm.mode = (msqkptr->u.msg_perm.mode & ~0777) |
605		    (msqbuf->msg_perm.mode & 0777);
606		msqkptr->u.msg_qbytes = msqbuf->msg_qbytes;
607		msqkptr->u.msg_ctime = time_second;
608		break;
609
610	case IPC_STAT:
611		if ((error = ipcperm(td, &msqkptr->u.msg_perm, IPC_R))) {
612			DPRINTF(("requester doesn't have read access\n"));
613			goto done2;
614		}
615		*msqbuf = msqkptr->u;
616		if (td->td_ucred->cr_prison != msqkptr->cred->cr_prison)
617			msqbuf->msg_perm.key = IPC_PRIVATE;
618
619		/*
620		 * Try to hide the fact that the structure layout is shared by
621		 * both the kernel and userland.  These pointers are not useful
622		 * to userspace.
623		 */
624		msqbuf->__msg_first = msqbuf->__msg_last = NULL;
625		break;
626
627	default:
628		DPRINTF(("invalid command %d\n", cmd));
629		error = EINVAL;
630		goto done2;
631	}
632
633	if (error == 0)
634		td->td_retval[0] = rval;
635done2:
636	mtx_unlock(&msq_mtx);
637	return (error);
638}
639
640#ifndef _SYS_SYSPROTO_H_
641struct msgget_args {
642	key_t	key;
643	int	msgflg;
644};
645#endif
646
647int
648sys_msgget(struct thread *td, struct msgget_args *uap)
649{
650	int msqid, error = 0;
651	int key = uap->key;
652	int msgflg = uap->msgflg;
653	struct ucred *cred = td->td_ucred;
654	struct msqid_kernel *msqkptr = NULL;
655
656	DPRINTF(("msgget(0x%x, 0%o)\n", key, msgflg));
657
658	if (msg_find_prison(cred) == NULL)
659		return (ENOSYS);
660
661	mtx_lock(&msq_mtx);
662	if (key != IPC_PRIVATE) {
663		for (msqid = 0; msqid < msginfo.msgmni; msqid++) {
664			msqkptr = &msqids[msqid];
665			if (msqkptr->u.msg_qbytes != 0 &&
666			    msqkptr->cred != NULL &&
667			    msqkptr->cred->cr_prison == cred->cr_prison &&
668			    msqkptr->u.msg_perm.key == key)
669				break;
670		}
671		if (msqid < msginfo.msgmni) {
672			DPRINTF(("found public key\n"));
673			if ((msgflg & IPC_CREAT) && (msgflg & IPC_EXCL)) {
674				DPRINTF(("not exclusive\n"));
675				error = EEXIST;
676				goto done2;
677			}
678			AUDIT_ARG_SVIPC_ID(IXSEQ_TO_IPCID(msqid,
679			    msqkptr->u.msg_perm));
680			if ((error = ipcperm(td, &msqkptr->u.msg_perm,
681			    msgflg & 0700))) {
682				DPRINTF(("requester doesn't have 0%o access\n",
683				    msgflg & 0700));
684				goto done2;
685			}
686#ifdef MAC
687			error = mac_sysvmsq_check_msqget(cred, msqkptr);
688			if (error != 0)
689				goto done2;
690#endif
691			goto found;
692		}
693	}
694
695	DPRINTF(("need to allocate the msqid_ds\n"));
696	if (key == IPC_PRIVATE || (msgflg & IPC_CREAT)) {
697		for (msqid = 0; msqid < msginfo.msgmni; msqid++) {
698			/*
699			 * Look for an unallocated and unlocked msqid_ds.
700			 * msqid_ds's can be locked by msgsnd or msgrcv while
701			 * they are copying the message in/out.  We can't
702			 * re-use the entry until they release it.
703			 */
704			msqkptr = &msqids[msqid];
705			if (msqkptr->u.msg_qbytes == 0 &&
706			    (msqkptr->u.msg_perm.mode & MSG_LOCKED) == 0)
707				break;
708		}
709		if (msqid == msginfo.msgmni) {
710			DPRINTF(("no more msqid_ds's available\n"));
711			error = ENOSPC;
712			goto done2;
713		}
714#ifdef RACCT
715		if (racct_enable) {
716			PROC_LOCK(td->td_proc);
717			error = racct_add(td->td_proc, RACCT_NMSGQ, 1);
718			PROC_UNLOCK(td->td_proc);
719			if (error != 0) {
720				error = ENOSPC;
721				goto done2;
722			}
723		}
724#endif
725		DPRINTF(("msqid %d is available\n", msqid));
726		msqkptr->u.msg_perm.key = key;
727		msqkptr->u.msg_perm.cuid = cred->cr_uid;
728		msqkptr->u.msg_perm.uid = cred->cr_uid;
729		msqkptr->u.msg_perm.cgid = cred->cr_gid;
730		msqkptr->u.msg_perm.gid = cred->cr_gid;
731		msqkptr->u.msg_perm.mode = (msgflg & 0777);
732		msqkptr->cred = crhold(cred);
733		/* Make sure that the returned msqid is unique */
734		msqkptr->u.msg_perm.seq = (msqkptr->u.msg_perm.seq + 1) & 0x7fff;
735		msqkptr->u.__msg_first = NULL;
736		msqkptr->u.__msg_last = NULL;
737		msqkptr->u.msg_cbytes = 0;
738		msqkptr->u.msg_qnum = 0;
739		msqkptr->u.msg_qbytes = msginfo.msgmnb;
740		msqkptr->u.msg_lspid = 0;
741		msqkptr->u.msg_lrpid = 0;
742		msqkptr->u.msg_stime = 0;
743		msqkptr->u.msg_rtime = 0;
744		msqkptr->u.msg_ctime = time_second;
745#ifdef MAC
746		mac_sysvmsq_create(cred, msqkptr);
747#endif
748		AUDIT_ARG_SVIPC_PERM(&msqkptr->u.msg_perm);
749	} else {
750		DPRINTF(("didn't find it and wasn't asked to create it\n"));
751		error = ENOENT;
752		goto done2;
753	}
754
755found:
756	/* Construct the unique msqid */
757	td->td_retval[0] = IXSEQ_TO_IPCID(msqid, msqkptr->u.msg_perm);
758done2:
759	mtx_unlock(&msq_mtx);
760	return (error);
761}
762
763#ifndef _SYS_SYSPROTO_H_
764struct msgsnd_args {
765	int	msqid;
766	const void	*msgp;	/* XXX msgp is actually mtext. */
767	size_t	msgsz;
768	int	msgflg;
769};
770#endif
771int
772kern_msgsnd(struct thread *td, int msqid, const void *msgp,
773    size_t msgsz, int msgflg, long mtype)
774{
775	int msqix, segs_needed, error = 0;
776	struct msqid_kernel *msqkptr;
777	struct msg *msghdr;
778	struct prison *rpr;
779	short next;
780#ifdef RACCT
781	size_t saved_msgsz = 0;
782#endif
783
784	rpr = msg_find_prison(td->td_ucred);
785	if (rpr == NULL)
786		return (ENOSYS);
787
788	mtx_lock(&msq_mtx);
789	AUDIT_ARG_SVIPC_ID(msqid);
790	msqix = IPCID_TO_IX(msqid);
791
792	if (msqix < 0 || msqix >= msginfo.msgmni) {
793		DPRINTF(("msqid (%d) out of range (0<=msqid<%d)\n", msqix,
794		    msginfo.msgmni));
795		error = EINVAL;
796		goto done2;
797	}
798
799	msqkptr = &msqids[msqix];
800	AUDIT_ARG_SVIPC_PERM(&msqkptr->u.msg_perm);
801	if (msqkptr->u.msg_qbytes == 0) {
802		DPRINTF(("no such message queue id\n"));
803		error = EINVAL;
804		goto done2;
805	}
806	if (msqkptr->u.msg_perm.seq != IPCID_TO_SEQ(msqid)) {
807		DPRINTF(("wrong sequence number\n"));
808		error = EINVAL;
809		goto done2;
810	}
811
812	if ((error = msq_prison_cansee(rpr, msqkptr))) {
813		DPRINTF(("requester can't see prison\n"));
814		goto done2;
815	}
816
817	if ((error = ipcperm(td, &msqkptr->u.msg_perm, IPC_W))) {
818		DPRINTF(("requester doesn't have write access\n"));
819		goto done2;
820	}
821
822#ifdef MAC
823	error = mac_sysvmsq_check_msqsnd(td->td_ucred, msqkptr);
824	if (error != 0)
825		goto done2;
826#endif
827
828#ifdef RACCT
829	if (racct_enable) {
830		PROC_LOCK(td->td_proc);
831		if (racct_add(td->td_proc, RACCT_MSGQQUEUED, 1)) {
832			PROC_UNLOCK(td->td_proc);
833			error = EAGAIN;
834			goto done2;
835		}
836		saved_msgsz = msgsz;
837		if (racct_add(td->td_proc, RACCT_MSGQSIZE, msgsz)) {
838			racct_sub(td->td_proc, RACCT_MSGQQUEUED, 1);
839			PROC_UNLOCK(td->td_proc);
840			error = EAGAIN;
841			goto done2;
842		}
843		PROC_UNLOCK(td->td_proc);
844	}
845#endif
846
847	segs_needed = howmany(msgsz, msginfo.msgssz);
848	DPRINTF(("msgsz=%zu, msgssz=%d, segs_needed=%d\n", msgsz,
849	    msginfo.msgssz, segs_needed));
850	for (;;) {
851		int need_more_resources = 0;
852
853		/*
854		 * check msgsz
855		 * (inside this loop in case msg_qbytes changes while we sleep)
856		 */
857
858		if (msgsz > msqkptr->u.msg_qbytes) {
859			DPRINTF(("msgsz > msqkptr->u.msg_qbytes\n"));
860			error = EINVAL;
861			goto done3;
862		}
863
864		if (msqkptr->u.msg_perm.mode & MSG_LOCKED) {
865			DPRINTF(("msqid is locked\n"));
866			need_more_resources = 1;
867		}
868		if (msgsz + msqkptr->u.msg_cbytes > msqkptr->u.msg_qbytes) {
869			DPRINTF(("msgsz + msg_cbytes > msg_qbytes\n"));
870			need_more_resources = 1;
871		}
872		if (segs_needed > nfree_msgmaps) {
873			DPRINTF(("segs_needed > nfree_msgmaps\n"));
874			need_more_resources = 1;
875		}
876		if (free_msghdrs == NULL) {
877			DPRINTF(("no more msghdrs\n"));
878			need_more_resources = 1;
879		}
880
881		if (need_more_resources) {
882			int we_own_it;
883
884			if ((msgflg & IPC_NOWAIT) != 0) {
885				DPRINTF(("need more resources but caller "
886				    "doesn't want to wait\n"));
887				error = EAGAIN;
888				goto done3;
889			}
890
891			if ((msqkptr->u.msg_perm.mode & MSG_LOCKED) != 0) {
892				DPRINTF(("we don't own the msqid_ds\n"));
893				we_own_it = 0;
894			} else {
895				/* Force later arrivals to wait for our
896				   request */
897				DPRINTF(("we own the msqid_ds\n"));
898				msqkptr->u.msg_perm.mode |= MSG_LOCKED;
899				we_own_it = 1;
900			}
901			DPRINTF(("msgsnd:  goodnight\n"));
902			error = msleep(msqkptr, &msq_mtx, (PZERO - 4) | PCATCH,
903			    "msgsnd", hz);
904			DPRINTF(("msgsnd:  good morning, error=%d\n", error));
905			if (we_own_it)
906				msqkptr->u.msg_perm.mode &= ~MSG_LOCKED;
907			if (error == EWOULDBLOCK) {
908				DPRINTF(("msgsnd:  timed out\n"));
909				continue;
910			}
911			if (error != 0) {
912				DPRINTF(("msgsnd:  interrupted system call\n"));
913				error = EINTR;
914				goto done3;
915			}
916
917			/*
918			 * Make sure that the msq queue still exists
919			 */
920
921			if (msqkptr->u.msg_qbytes == 0) {
922				DPRINTF(("msqid deleted\n"));
923				error = EIDRM;
924				goto done3;
925			}
926
927		} else {
928			DPRINTF(("got all the resources that we need\n"));
929			break;
930		}
931	}
932
933	/*
934	 * We have the resources that we need.
935	 * Make sure!
936	 */
937
938	if (msqkptr->u.msg_perm.mode & MSG_LOCKED)
939		panic("msg_perm.mode & MSG_LOCKED");
940	if (segs_needed > nfree_msgmaps)
941		panic("segs_needed > nfree_msgmaps");
942	if (msgsz + msqkptr->u.msg_cbytes > msqkptr->u.msg_qbytes)
943		panic("msgsz + msg_cbytes > msg_qbytes");
944	if (free_msghdrs == NULL)
945		panic("no more msghdrs");
946
947	/*
948	 * Re-lock the msqid_ds in case we page-fault when copying in the
949	 * message
950	 */
951
952	if ((msqkptr->u.msg_perm.mode & MSG_LOCKED) != 0)
953		panic("msqid_ds is already locked");
954	msqkptr->u.msg_perm.mode |= MSG_LOCKED;
955
956	/*
957	 * Allocate a message header
958	 */
959
960	msghdr = free_msghdrs;
961	free_msghdrs = msghdr->msg_next;
962	msghdr->msg_spot = -1;
963	msghdr->msg_ts = msgsz;
964	msghdr->msg_type = mtype;
965#ifdef MAC
966	/*
967	 * XXXMAC: Should the mac_sysvmsq_check_msgmsq check follow here
968	 * immediately?  Or, should it be checked just before the msg is
969	 * enqueued in the msgq (as it is done now)?
970	 */
971	mac_sysvmsg_create(td->td_ucred, msqkptr, msghdr);
972#endif
973
974	/*
975	 * Allocate space for the message
976	 */
977
978	while (segs_needed > 0) {
979		if (nfree_msgmaps <= 0)
980			panic("not enough msgmaps");
981		if (free_msgmaps == -1)
982			panic("nil free_msgmaps");
983		next = free_msgmaps;
984		if (next <= -1)
985			panic("next too low #1");
986		if (next >= msginfo.msgseg)
987			panic("next out of range #1");
988		DPRINTF(("allocating segment %d to message\n", next));
989		free_msgmaps = msgmaps[next].next;
990		nfree_msgmaps--;
991		msgmaps[next].next = msghdr->msg_spot;
992		msghdr->msg_spot = next;
993		segs_needed--;
994	}
995
996	/*
997	 * Validate the message type
998	 */
999
1000	if (msghdr->msg_type < 1) {
1001		msg_freehdr(msghdr);
1002		msqkptr->u.msg_perm.mode &= ~MSG_LOCKED;
1003		wakeup(msqkptr);
1004		DPRINTF(("mtype (%ld) < 1\n", msghdr->msg_type));
1005		error = EINVAL;
1006		goto done3;
1007	}
1008
1009	/*
1010	 * Copy in the message body
1011	 */
1012
1013	next = msghdr->msg_spot;
1014	while (msgsz > 0) {
1015		size_t tlen;
1016		if (msgsz > msginfo.msgssz)
1017			tlen = msginfo.msgssz;
1018		else
1019			tlen = msgsz;
1020		if (next <= -1)
1021			panic("next too low #2");
1022		if (next >= msginfo.msgseg)
1023			panic("next out of range #2");
1024		mtx_unlock(&msq_mtx);
1025		if ((error = copyin(msgp, &msgpool[next * msginfo.msgssz],
1026		    tlen)) != 0) {
1027			mtx_lock(&msq_mtx);
1028			DPRINTF(("error %d copying in message segment\n",
1029			    error));
1030			msg_freehdr(msghdr);
1031			msqkptr->u.msg_perm.mode &= ~MSG_LOCKED;
1032			wakeup(msqkptr);
1033			goto done3;
1034		}
1035		mtx_lock(&msq_mtx);
1036		msgsz -= tlen;
1037		msgp = (const char *)msgp + tlen;
1038		next = msgmaps[next].next;
1039	}
1040	if (next != -1)
1041		panic("didn't use all the msg segments");
1042
1043	/*
1044	 * We've got the message.  Unlock the msqid_ds.
1045	 */
1046
1047	msqkptr->u.msg_perm.mode &= ~MSG_LOCKED;
1048
1049	/*
1050	 * Make sure that the msqid_ds is still allocated.
1051	 */
1052
1053	if (msqkptr->u.msg_qbytes == 0) {
1054		msg_freehdr(msghdr);
1055		wakeup(msqkptr);
1056		error = EIDRM;
1057		goto done3;
1058	}
1059
1060#ifdef MAC
1061	/*
1062	 * Note: Since the task/thread allocates the msghdr and usually
1063	 * primes it with its own MAC label, for a majority of policies, it
1064	 * won't be necessary to check whether the msghdr has access
1065	 * permissions to the msgq.  The mac_sysvmsq_check_msqsnd check would
1066	 * suffice in that case.  However, this hook may be required where
1067	 * individual policies derive a non-identical label for the msghdr
1068	 * from the current thread label and may want to check the msghdr
1069	 * enqueue permissions, along with read/write permissions to the
1070	 * msgq.
1071	 */
1072	error = mac_sysvmsq_check_msgmsq(td->td_ucred, msghdr, msqkptr);
1073	if (error != 0) {
1074		msg_freehdr(msghdr);
1075		wakeup(msqkptr);
1076		goto done3;
1077	}
1078#endif
1079
1080	/*
1081	 * Put the message into the queue
1082	 */
1083	if (msqkptr->u.__msg_first == NULL) {
1084		msqkptr->u.__msg_first = msghdr;
1085		msqkptr->u.__msg_last = msghdr;
1086	} else {
1087		msqkptr->u.__msg_last->msg_next = msghdr;
1088		msqkptr->u.__msg_last = msghdr;
1089	}
1090	msqkptr->u.__msg_last->msg_next = NULL;
1091
1092	msqkptr->u.msg_cbytes += msghdr->msg_ts;
1093	msqkptr->u.msg_qnum++;
1094	msqkptr->u.msg_lspid = td->td_proc->p_pid;
1095	msqkptr->u.msg_stime = time_second;
1096
1097	wakeup(msqkptr);
1098	td->td_retval[0] = 0;
1099done3:
1100#ifdef RACCT
1101	if (racct_enable && error != 0) {
1102		PROC_LOCK(td->td_proc);
1103		racct_sub(td->td_proc, RACCT_MSGQQUEUED, 1);
1104		racct_sub(td->td_proc, RACCT_MSGQSIZE, saved_msgsz);
1105		PROC_UNLOCK(td->td_proc);
1106	}
1107#endif
1108done2:
1109	mtx_unlock(&msq_mtx);
1110	return (error);
1111}
1112
1113int
1114sys_msgsnd(struct thread *td, struct msgsnd_args *uap)
1115{
1116	int error;
1117	long mtype;
1118
1119	DPRINTF(("call to msgsnd(%d, %p, %zu, %d)\n", uap->msqid, uap->msgp,
1120	    uap->msgsz, uap->msgflg));
1121
1122	if ((error = copyin(uap->msgp, &mtype, sizeof(mtype))) != 0) {
1123		DPRINTF(("error %d copying the message type\n", error));
1124		return (error);
1125	}
1126	return (kern_msgsnd(td, uap->msqid,
1127	    (const char *)uap->msgp + sizeof(mtype),
1128	    uap->msgsz, uap->msgflg, mtype));
1129}
1130
1131#ifndef _SYS_SYSPROTO_H_
1132struct msgrcv_args {
1133	int	msqid;
1134	void	*msgp;
1135	size_t	msgsz;
1136	long	msgtyp;
1137	int	msgflg;
1138};
1139#endif
1140/* XXX msgp is actually mtext. */
1141int
1142kern_msgrcv(struct thread *td, int msqid, void *msgp, size_t msgsz, long msgtyp,
1143    int msgflg, long *mtype)
1144{
1145	size_t len;
1146	struct msqid_kernel *msqkptr;
1147	struct msg *msghdr;
1148	struct prison *rpr;
1149	int msqix, error = 0;
1150	short next;
1151
1152	rpr = msg_find_prison(td->td_ucred);
1153	if (rpr == NULL)
1154		return (ENOSYS);
1155
1156	AUDIT_ARG_SVIPC_ID(msqid);
1157	msqix = IPCID_TO_IX(msqid);
1158
1159	if (msqix < 0 || msqix >= msginfo.msgmni) {
1160		DPRINTF(("msqid (%d) out of range (0<=msqid<%d)\n", msqix,
1161		    msginfo.msgmni));
1162		return (EINVAL);
1163	}
1164
1165	msqkptr = &msqids[msqix];
1166	mtx_lock(&msq_mtx);
1167	AUDIT_ARG_SVIPC_PERM(&msqkptr->u.msg_perm);
1168	if (msqkptr->u.msg_qbytes == 0) {
1169		DPRINTF(("no such message queue id\n"));
1170		error = EINVAL;
1171		goto done2;
1172	}
1173	if (msqkptr->u.msg_perm.seq != IPCID_TO_SEQ(msqid)) {
1174		DPRINTF(("wrong sequence number\n"));
1175		error = EINVAL;
1176		goto done2;
1177	}
1178
1179	if ((error = msq_prison_cansee(rpr, msqkptr))) {
1180		DPRINTF(("requester can't see prison\n"));
1181		goto done2;
1182	}
1183
1184	if ((error = ipcperm(td, &msqkptr->u.msg_perm, IPC_R))) {
1185		DPRINTF(("requester doesn't have read access\n"));
1186		goto done2;
1187	}
1188
1189#ifdef MAC
1190	error = mac_sysvmsq_check_msqrcv(td->td_ucred, msqkptr);
1191	if (error != 0)
1192		goto done2;
1193#endif
1194
1195	msghdr = NULL;
1196	while (msghdr == NULL) {
1197		if (msgtyp == 0) {
1198			msghdr = msqkptr->u.__msg_first;
1199			if (msghdr != NULL) {
1200				if (msgsz < msghdr->msg_ts &&
1201				    (msgflg & MSG_NOERROR) == 0) {
1202					DPRINTF(("first message on the queue "
1203					    "is too big (want %zu, got %d)\n",
1204					    msgsz, msghdr->msg_ts));
1205					error = E2BIG;
1206					goto done2;
1207				}
1208#ifdef MAC
1209				error = mac_sysvmsq_check_msgrcv(td->td_ucred,
1210				    msghdr);
1211				if (error != 0)
1212					goto done2;
1213#endif
1214				if (msqkptr->u.__msg_first ==
1215				    msqkptr->u.__msg_last) {
1216					msqkptr->u.__msg_first = NULL;
1217					msqkptr->u.__msg_last = NULL;
1218				} else {
1219					msqkptr->u.__msg_first = msghdr->msg_next;
1220					if (msqkptr->u.__msg_first == NULL)
1221						panic("msg_first/last screwed up #1");
1222				}
1223			}
1224		} else {
1225			struct msg *previous;
1226			struct msg **prev;
1227
1228			previous = NULL;
1229			prev = &(msqkptr->u.__msg_first);
1230			while ((msghdr = *prev) != NULL) {
1231				/*
1232				 * Is this message's type an exact match or is
1233				 * this message's type less than or equal to
1234				 * the absolute value of a negative msgtyp?
1235				 * Note that the second half of this test can
1236				 * NEVER be true if msgtyp is positive since
1237				 * msg_type is always positive!
1238				 */
1239
1240				if (msgtyp == msghdr->msg_type ||
1241				    msghdr->msg_type <= -msgtyp) {
1242					DPRINTF(("found message type %ld, "
1243					    "requested %ld\n",
1244					    msghdr->msg_type, msgtyp));
1245					if (msgsz < msghdr->msg_ts &&
1246					    (msgflg & MSG_NOERROR) == 0) {
1247						DPRINTF(("requested message "
1248						    "on the queue is too big "
1249						    "(want %zu, got %hu)\n",
1250						    msgsz, msghdr->msg_ts));
1251						error = E2BIG;
1252						goto done2;
1253					}
1254#ifdef MAC
1255					error = mac_sysvmsq_check_msgrcv(
1256					    td->td_ucred, msghdr);
1257					if (error != 0)
1258						goto done2;
1259#endif
1260					*prev = msghdr->msg_next;
1261					if (msghdr == msqkptr->u.__msg_last) {
1262						if (previous == NULL) {
1263							if (prev !=
1264							    &msqkptr->u.__msg_first)
1265								panic("__msg_first/last screwed up #2");
1266							msqkptr->u.__msg_first =
1267							    NULL;
1268							msqkptr->u.__msg_last =
1269							    NULL;
1270						} else {
1271							if (prev ==
1272							    &msqkptr->u.__msg_first)
1273								panic("__msg_first/last screwed up #3");
1274							msqkptr->u.__msg_last =
1275							    previous;
1276						}
1277					}
1278					break;
1279				}
1280				previous = msghdr;
1281				prev = &(msghdr->msg_next);
1282			}
1283		}
1284
1285		/*
1286		 * We've either extracted the msghdr for the appropriate
1287		 * message or there isn't one.
1288		 * If there is one then bail out of this loop.
1289		 */
1290
1291		if (msghdr != NULL)
1292			break;
1293
1294		/*
1295		 * Hmph!  No message found.  Does the user want to wait?
1296		 */
1297
1298		if ((msgflg & IPC_NOWAIT) != 0) {
1299			DPRINTF(("no appropriate message found (msgtyp=%ld)\n",
1300			    msgtyp));
1301			/* The SVID says to return ENOMSG. */
1302			error = ENOMSG;
1303			goto done2;
1304		}
1305
1306		/*
1307		 * Wait for something to happen
1308		 */
1309
1310		DPRINTF(("msgrcv:  goodnight\n"));
1311		error = msleep(msqkptr, &msq_mtx, (PZERO - 4) | PCATCH,
1312		    "msgrcv", 0);
1313		DPRINTF(("msgrcv:  good morning (error=%d)\n", error));
1314
1315		if (error != 0) {
1316			DPRINTF(("msgrcv:  interrupted system call\n"));
1317			error = EINTR;
1318			goto done2;
1319		}
1320
1321		/*
1322		 * Make sure that the msq queue still exists
1323		 */
1324
1325		if (msqkptr->u.msg_qbytes == 0 ||
1326		    msqkptr->u.msg_perm.seq != IPCID_TO_SEQ(msqid)) {
1327			DPRINTF(("msqid deleted\n"));
1328			error = EIDRM;
1329			goto done2;
1330		}
1331	}
1332
1333	/*
1334	 * Return the message to the user.
1335	 *
1336	 * First, do the bookkeeping (before we risk being interrupted).
1337	 */
1338
1339	msqkptr->u.msg_cbytes -= msghdr->msg_ts;
1340	msqkptr->u.msg_qnum--;
1341	msqkptr->u.msg_lrpid = td->td_proc->p_pid;
1342	msqkptr->u.msg_rtime = time_second;
1343
1344	racct_sub_cred(msqkptr->cred, RACCT_MSGQQUEUED, 1);
1345	racct_sub_cred(msqkptr->cred, RACCT_MSGQSIZE, msghdr->msg_ts);
1346
1347	/*
1348	 * Make msgsz the actual amount that we'll be returning.
1349	 * Note that this effectively truncates the message if it is too long
1350	 * (since msgsz is never increased).
1351	 */
1352
1353	DPRINTF(("found a message, msgsz=%zu, msg_ts=%hu\n", msgsz,
1354	    msghdr->msg_ts));
1355	if (msgsz > msghdr->msg_ts)
1356		msgsz = msghdr->msg_ts;
1357	*mtype = msghdr->msg_type;
1358
1359	/*
1360	 * Return the segments to the user
1361	 */
1362
1363	next = msghdr->msg_spot;
1364	for (len = 0; len < msgsz; len += msginfo.msgssz) {
1365		size_t tlen;
1366
1367		if (msgsz - len > msginfo.msgssz)
1368			tlen = msginfo.msgssz;
1369		else
1370			tlen = msgsz - len;
1371		if (next <= -1)
1372			panic("next too low #3");
1373		if (next >= msginfo.msgseg)
1374			panic("next out of range #3");
1375		mtx_unlock(&msq_mtx);
1376		error = copyout(&msgpool[next * msginfo.msgssz], msgp, tlen);
1377		mtx_lock(&msq_mtx);
1378		if (error != 0) {
1379			DPRINTF(("error (%d) copying out message segment\n",
1380			    error));
1381			msg_freehdr(msghdr);
1382			wakeup(msqkptr);
1383			goto done2;
1384		}
1385		msgp = (char *)msgp + tlen;
1386		next = msgmaps[next].next;
1387	}
1388
1389	/*
1390	 * Done, return the actual number of bytes copied out.
1391	 */
1392
1393	msg_freehdr(msghdr);
1394	wakeup(msqkptr);
1395	td->td_retval[0] = msgsz;
1396done2:
1397	mtx_unlock(&msq_mtx);
1398	return (error);
1399}
1400
1401int
1402sys_msgrcv(struct thread *td, struct msgrcv_args *uap)
1403{
1404	int error;
1405	long mtype;
1406
1407	DPRINTF(("call to msgrcv(%d, %p, %zu, %ld, %d)\n", uap->msqid,
1408	    uap->msgp, uap->msgsz, uap->msgtyp, uap->msgflg));
1409
1410	if ((error = kern_msgrcv(td, uap->msqid,
1411	    (char *)uap->msgp + sizeof(mtype), uap->msgsz,
1412	    uap->msgtyp, uap->msgflg, &mtype)) != 0)
1413		return (error);
1414	if ((error = copyout(&mtype, uap->msgp, sizeof(mtype))) != 0)
1415		DPRINTF(("error %d copying the message type\n", error));
1416	return (error);
1417}
1418
1419static int
1420sysctl_msqids(SYSCTL_HANDLER_ARGS)
1421{
1422	struct msqid_kernel tmsqk;
1423#ifdef COMPAT_FREEBSD32
1424	struct msqid_kernel32 tmsqk32;
1425#endif
1426	struct prison *pr, *rpr;
1427	void *outaddr;
1428	size_t outsize;
1429	int error, i;
1430
1431	pr = req->td->td_ucred->cr_prison;
1432	rpr = msg_find_prison(req->td->td_ucred);
1433	error = 0;
1434	for (i = 0; i < msginfo.msgmni; i++) {
1435		mtx_lock(&msq_mtx);
1436		if (msqids[i].u.msg_qbytes == 0 || rpr == NULL ||
1437		    msq_prison_cansee(rpr, &msqids[i]) != 0)
1438			bzero(&tmsqk, sizeof(tmsqk));
1439		else {
1440			tmsqk = msqids[i];
1441			if (tmsqk.cred->cr_prison != pr)
1442				tmsqk.u.msg_perm.key = IPC_PRIVATE;
1443		}
1444		mtx_unlock(&msq_mtx);
1445#ifdef COMPAT_FREEBSD32
1446		if (SV_CURPROC_FLAG(SV_ILP32)) {
1447			bzero(&tmsqk32, sizeof(tmsqk32));
1448			freebsd32_ipcperm_out(&tmsqk.u.msg_perm,
1449			    &tmsqk32.u.msg_perm);
1450			/* Don't copy u.msg_first or u.msg_last */
1451			CP(tmsqk, tmsqk32, u.msg_cbytes);
1452			CP(tmsqk, tmsqk32, u.msg_qnum);
1453			CP(tmsqk, tmsqk32, u.msg_qbytes);
1454			CP(tmsqk, tmsqk32, u.msg_lspid);
1455			CP(tmsqk, tmsqk32, u.msg_lrpid);
1456			CP(tmsqk, tmsqk32, u.msg_stime);
1457			CP(tmsqk, tmsqk32, u.msg_rtime);
1458			CP(tmsqk, tmsqk32, u.msg_ctime);
1459			/* Don't copy label or cred */
1460			outaddr = &tmsqk32;
1461			outsize = sizeof(tmsqk32);
1462		} else
1463#endif
1464		{
1465			/* Don't leak kernel pointers */
1466			tmsqk.u.__msg_first = NULL;
1467			tmsqk.u.__msg_last = NULL;
1468			tmsqk.label = NULL;
1469			tmsqk.cred = NULL;
1470			/*
1471			 * XXX: some padding also exists, but we take care to
1472			 * allocate our pool of msqid_kernel structs with
1473			 * zeroed memory so this should be OK.
1474			 */
1475			outaddr = &tmsqk;
1476			outsize = sizeof(tmsqk);
1477		}
1478		error = SYSCTL_OUT(req, outaddr, outsize);
1479		if (error != 0)
1480			break;
1481	}
1482	return (error);
1483}
1484
1485SYSCTL_INT(_kern_ipc, OID_AUTO, msgmax, CTLFLAG_RD, &msginfo.msgmax, 0,
1486    "Maximum message size");
1487SYSCTL_INT(_kern_ipc, OID_AUTO, msgmni, CTLFLAG_RDTUN, &msginfo.msgmni, 0,
1488    "Number of message queue identifiers");
1489SYSCTL_INT(_kern_ipc, OID_AUTO, msgmnb, CTLFLAG_RDTUN, &msginfo.msgmnb, 0,
1490    "Maximum number of bytes in a queue");
1491SYSCTL_INT(_kern_ipc, OID_AUTO, msgtql, CTLFLAG_RDTUN, &msginfo.msgtql, 0,
1492    "Maximum number of messages in the system");
1493SYSCTL_INT(_kern_ipc, OID_AUTO, msgssz, CTLFLAG_RDTUN, &msginfo.msgssz, 0,
1494    "Size of a message segment");
1495SYSCTL_INT(_kern_ipc, OID_AUTO, msgseg, CTLFLAG_RDTUN, &msginfo.msgseg, 0,
1496    "Number of message segments");
1497SYSCTL_PROC(_kern_ipc, OID_AUTO, msqids,
1498    CTLTYPE_OPAQUE | CTLFLAG_RD | CTLFLAG_MPSAFE,
1499    NULL, 0, sysctl_msqids, "",
1500    "Array of struct msqid_kernel for each potential message queue");
1501
1502static int
1503msg_prison_check(void *obj, void *data)
1504{
1505	struct prison *pr = obj;
1506	struct prison *prpr;
1507	struct vfsoptlist *opts = data;
1508	int error, jsys;
1509
1510	/*
1511	 * sysvmsg is a jailsys integer.
1512	 * It must be "disable" if the parent jail is disabled.
1513	 */
1514	error = vfs_copyopt(opts, "sysvmsg", &jsys, sizeof(jsys));
1515	if (error != ENOENT) {
1516		if (error != 0)
1517			return (error);
1518		switch (jsys) {
1519		case JAIL_SYS_DISABLE:
1520			break;
1521		case JAIL_SYS_NEW:
1522		case JAIL_SYS_INHERIT:
1523			prison_lock(pr->pr_parent);
1524			prpr = osd_jail_get(pr->pr_parent, msg_prison_slot);
1525			prison_unlock(pr->pr_parent);
1526			if (prpr == NULL)
1527				return (EPERM);
1528			break;
1529		default:
1530			return (EINVAL);
1531		}
1532	}
1533
1534	return (0);
1535}
1536
1537static int
1538msg_prison_set(void *obj, void *data)
1539{
1540	struct prison *pr = obj;
1541	struct prison *tpr, *orpr, *nrpr, *trpr;
1542	struct vfsoptlist *opts = data;
1543	void *rsv;
1544	int jsys, descend;
1545
1546	/*
1547	 * sysvmsg controls which jail is the root of the associated msgs (this
1548	 * jail or same as the parent), or if the feature is available at all.
1549	 */
1550	if (vfs_copyopt(opts, "sysvmsg", &jsys, sizeof(jsys)) == ENOENT)
1551		jsys = vfs_flagopt(opts, "allow.sysvipc", NULL, 0)
1552		    ? JAIL_SYS_INHERIT
1553		    : vfs_flagopt(opts, "allow.nosysvipc", NULL, 0)
1554		    ? JAIL_SYS_DISABLE
1555		    : -1;
1556	if (jsys == JAIL_SYS_DISABLE) {
1557		prison_lock(pr);
1558		orpr = osd_jail_get(pr, msg_prison_slot);
1559		if (orpr != NULL)
1560			osd_jail_del(pr, msg_prison_slot);
1561		prison_unlock(pr);
1562		if (orpr != NULL) {
1563			if (orpr == pr)
1564				msg_prison_cleanup(pr);
1565			/* Disable all child jails as well. */
1566			FOREACH_PRISON_DESCENDANT(pr, tpr, descend) {
1567				prison_lock(tpr);
1568				trpr = osd_jail_get(tpr, msg_prison_slot);
1569				if (trpr != NULL) {
1570					osd_jail_del(tpr, msg_prison_slot);
1571					prison_unlock(tpr);
1572					if (trpr == tpr)
1573						msg_prison_cleanup(tpr);
1574				} else {
1575					prison_unlock(tpr);
1576					descend = 0;
1577				}
1578			}
1579		}
1580	} else if (jsys != -1) {
1581		if (jsys == JAIL_SYS_NEW)
1582			nrpr = pr;
1583		else {
1584			prison_lock(pr->pr_parent);
1585			nrpr = osd_jail_get(pr->pr_parent, msg_prison_slot);
1586			prison_unlock(pr->pr_parent);
1587		}
1588		rsv = osd_reserve(msg_prison_slot);
1589		prison_lock(pr);
1590		orpr = osd_jail_get(pr, msg_prison_slot);
1591		if (orpr != nrpr)
1592			(void)osd_jail_set_reserved(pr, msg_prison_slot, rsv,
1593			    nrpr);
1594		else
1595			osd_free_reserved(rsv);
1596		prison_unlock(pr);
1597		if (orpr != nrpr) {
1598			if (orpr == pr)
1599				msg_prison_cleanup(pr);
1600			if (orpr != NULL) {
1601				/* Change child jails matching the old root, */
1602				FOREACH_PRISON_DESCENDANT(pr, tpr, descend) {
1603					prison_lock(tpr);
1604					trpr = osd_jail_get(tpr,
1605					    msg_prison_slot);
1606					if (trpr == orpr) {
1607						(void)osd_jail_set(tpr,
1608						    msg_prison_slot, nrpr);
1609						prison_unlock(tpr);
1610						if (trpr == tpr)
1611							msg_prison_cleanup(tpr);
1612					} else {
1613						prison_unlock(tpr);
1614						descend = 0;
1615					}
1616				}
1617			}
1618		}
1619	}
1620
1621	return (0);
1622}
1623
1624static int
1625msg_prison_get(void *obj, void *data)
1626{
1627	struct prison *pr = obj;
1628	struct prison *rpr;
1629	struct vfsoptlist *opts = data;
1630	int error, jsys;
1631
1632	/* Set sysvmsg based on the jail's root prison. */
1633	prison_lock(pr);
1634	rpr = osd_jail_get(pr, msg_prison_slot);
1635	prison_unlock(pr);
1636	jsys = rpr == NULL ? JAIL_SYS_DISABLE
1637	    : rpr == pr ? JAIL_SYS_NEW : JAIL_SYS_INHERIT;
1638	error = vfs_setopt(opts, "sysvmsg", &jsys, sizeof(jsys));
1639	if (error == ENOENT)
1640		error = 0;
1641	return (error);
1642}
1643
1644static int
1645msg_prison_remove(void *obj, void *data __unused)
1646{
1647	struct prison *pr = obj;
1648	struct prison *rpr;
1649
1650	prison_lock(pr);
1651	rpr = osd_jail_get(pr, msg_prison_slot);
1652	prison_unlock(pr);
1653	if (rpr == pr)
1654		msg_prison_cleanup(pr);
1655	return (0);
1656}
1657
1658static void
1659msg_prison_cleanup(struct prison *pr)
1660{
1661	struct msqid_kernel *msqkptr;
1662	int i;
1663
1664	/* Remove any msqs that belong to this jail. */
1665	mtx_lock(&msq_mtx);
1666	for (i = 0; i < msginfo.msgmni; i++) {
1667		msqkptr = &msqids[i];
1668		if (msqkptr->u.msg_qbytes != 0 &&
1669		    msqkptr->cred != NULL && msqkptr->cred->cr_prison == pr)
1670			msq_remove(msqkptr);
1671	}
1672	mtx_unlock(&msq_mtx);
1673}
1674
1675SYSCTL_JAIL_PARAM_SYS_NODE(sysvmsg, CTLFLAG_RW, "SYSV message queues");
1676
1677#ifdef COMPAT_FREEBSD32
1678int
1679freebsd32_msgsys(struct thread *td, struct freebsd32_msgsys_args *uap)
1680{
1681
1682#if defined(COMPAT_FREEBSD4) || defined(COMPAT_FREEBSD5) || \
1683    defined(COMPAT_FREEBSD6) || defined(COMPAT_FREEBSD7)
1684	AUDIT_ARG_SVIPC_WHICH(uap->which);
1685	switch (uap->which) {
1686	case 0:
1687		return (freebsd7_freebsd32_msgctl(td,
1688		    (struct freebsd7_freebsd32_msgctl_args *)&uap->a2));
1689	case 2:
1690		return (freebsd32_msgsnd(td,
1691		    (struct freebsd32_msgsnd_args *)&uap->a2));
1692	case 3:
1693		return (freebsd32_msgrcv(td,
1694		    (struct freebsd32_msgrcv_args *)&uap->a2));
1695	default:
1696		return (sys_msgsys(td, (struct msgsys_args *)uap));
1697	}
1698#else
1699	return (nosys(td, NULL));
1700#endif
1701}
1702
1703#if defined(COMPAT_FREEBSD4) || defined(COMPAT_FREEBSD5) || \
1704    defined(COMPAT_FREEBSD6) || defined(COMPAT_FREEBSD7)
1705int
1706freebsd7_freebsd32_msgctl(struct thread *td,
1707    struct freebsd7_freebsd32_msgctl_args *uap)
1708{
1709	struct msqid_ds msqbuf;
1710	struct msqid_ds32_old msqbuf32;
1711	int error;
1712
1713	if (uap->cmd == IPC_SET) {
1714		error = copyin(uap->buf, &msqbuf32, sizeof(msqbuf32));
1715		if (error)
1716			return (error);
1717		freebsd32_ipcperm_old_in(&msqbuf32.msg_perm, &msqbuf.msg_perm);
1718		PTRIN_CP(msqbuf32, msqbuf, __msg_first);
1719		PTRIN_CP(msqbuf32, msqbuf, __msg_last);
1720		CP(msqbuf32, msqbuf, msg_cbytes);
1721		CP(msqbuf32, msqbuf, msg_qnum);
1722		CP(msqbuf32, msqbuf, msg_qbytes);
1723		CP(msqbuf32, msqbuf, msg_lspid);
1724		CP(msqbuf32, msqbuf, msg_lrpid);
1725		CP(msqbuf32, msqbuf, msg_stime);
1726		CP(msqbuf32, msqbuf, msg_rtime);
1727		CP(msqbuf32, msqbuf, msg_ctime);
1728	}
1729	error = kern_msgctl(td, uap->msqid, uap->cmd, &msqbuf);
1730	if (error)
1731		return (error);
1732	if (uap->cmd == IPC_STAT) {
1733		bzero(&msqbuf32, sizeof(msqbuf32));
1734		freebsd32_ipcperm_old_out(&msqbuf.msg_perm, &msqbuf32.msg_perm);
1735		PTROUT_CP(msqbuf, msqbuf32, __msg_first);
1736		PTROUT_CP(msqbuf, msqbuf32, __msg_last);
1737		CP(msqbuf, msqbuf32, msg_cbytes);
1738		CP(msqbuf, msqbuf32, msg_qnum);
1739		CP(msqbuf, msqbuf32, msg_qbytes);
1740		CP(msqbuf, msqbuf32, msg_lspid);
1741		CP(msqbuf, msqbuf32, msg_lrpid);
1742		CP(msqbuf, msqbuf32, msg_stime);
1743		CP(msqbuf, msqbuf32, msg_rtime);
1744		CP(msqbuf, msqbuf32, msg_ctime);
1745		error = copyout(&msqbuf32, uap->buf, sizeof(struct msqid_ds32));
1746	}
1747	return (error);
1748}
1749#endif
1750
1751int
1752freebsd32_msgctl(struct thread *td, struct freebsd32_msgctl_args *uap)
1753{
1754	struct msqid_ds msqbuf;
1755	struct msqid_ds32 msqbuf32;
1756	int error;
1757
1758	if (uap->cmd == IPC_SET) {
1759		error = copyin(uap->buf, &msqbuf32, sizeof(msqbuf32));
1760		if (error)
1761			return (error);
1762		freebsd32_ipcperm_in(&msqbuf32.msg_perm, &msqbuf.msg_perm);
1763		PTRIN_CP(msqbuf32, msqbuf, __msg_first);
1764		PTRIN_CP(msqbuf32, msqbuf, __msg_last);
1765		CP(msqbuf32, msqbuf, msg_cbytes);
1766		CP(msqbuf32, msqbuf, msg_qnum);
1767		CP(msqbuf32, msqbuf, msg_qbytes);
1768		CP(msqbuf32, msqbuf, msg_lspid);
1769		CP(msqbuf32, msqbuf, msg_lrpid);
1770		CP(msqbuf32, msqbuf, msg_stime);
1771		CP(msqbuf32, msqbuf, msg_rtime);
1772		CP(msqbuf32, msqbuf, msg_ctime);
1773	}
1774	error = kern_msgctl(td, uap->msqid, uap->cmd, &msqbuf);
1775	if (error)
1776		return (error);
1777	if (uap->cmd == IPC_STAT) {
1778		freebsd32_ipcperm_out(&msqbuf.msg_perm, &msqbuf32.msg_perm);
1779		PTROUT_CP(msqbuf, msqbuf32, __msg_first);
1780		PTROUT_CP(msqbuf, msqbuf32, __msg_last);
1781		CP(msqbuf, msqbuf32, msg_cbytes);
1782		CP(msqbuf, msqbuf32, msg_qnum);
1783		CP(msqbuf, msqbuf32, msg_qbytes);
1784		CP(msqbuf, msqbuf32, msg_lspid);
1785		CP(msqbuf, msqbuf32, msg_lrpid);
1786		CP(msqbuf, msqbuf32, msg_stime);
1787		CP(msqbuf, msqbuf32, msg_rtime);
1788		CP(msqbuf, msqbuf32, msg_ctime);
1789		error = copyout(&msqbuf32, uap->buf, sizeof(struct msqid_ds32));
1790	}
1791	return (error);
1792}
1793
1794int
1795freebsd32_msgsnd(struct thread *td, struct freebsd32_msgsnd_args *uap)
1796{
1797	const void *msgp;
1798	long mtype;
1799	int32_t mtype32;
1800	int error;
1801
1802	msgp = PTRIN(uap->msgp);
1803	if ((error = copyin(msgp, &mtype32, sizeof(mtype32))) != 0)
1804		return (error);
1805	mtype = mtype32;
1806	return (kern_msgsnd(td, uap->msqid,
1807	    (const char *)msgp + sizeof(mtype32),
1808	    uap->msgsz, uap->msgflg, mtype));
1809}
1810
1811int
1812freebsd32_msgrcv(struct thread *td, struct freebsd32_msgrcv_args *uap)
1813{
1814	void *msgp;
1815	long mtype;
1816	int32_t mtype32;
1817	int error;
1818
1819	msgp = PTRIN(uap->msgp);
1820	if ((error = kern_msgrcv(td, uap->msqid,
1821	    (char *)msgp + sizeof(mtype32), uap->msgsz,
1822	    uap->msgtyp, uap->msgflg, &mtype)) != 0)
1823		return (error);
1824	mtype32 = (int32_t)mtype;
1825	return (copyout(&mtype32, msgp, sizeof(mtype32)));
1826}
1827#endif
1828
1829#if defined(COMPAT_FREEBSD4) || defined(COMPAT_FREEBSD5) || \
1830    defined(COMPAT_FREEBSD6) || defined(COMPAT_FREEBSD7)
1831
1832/* XXX casting to (sy_call_t *) is bogus, as usual. */
1833static sy_call_t *msgcalls[] = {
1834	(sy_call_t *)freebsd7_msgctl, (sy_call_t *)sys_msgget,
1835	(sy_call_t *)sys_msgsnd, (sy_call_t *)sys_msgrcv
1836};
1837
1838/*
1839 * Entry point for all MSG calls.
1840 *
1841 * XXX actually varargs.
1842 * struct msgsys_args {
1843 *		int	which;
1844 *		int	a2;
1845 *		int	a3;
1846 *		int	a4;
1847 *		int	a5;
1848 *		int	a6;
1849 *	} *uap;
1850 */
1851int
1852sys_msgsys(struct thread *td, struct msgsys_args *uap)
1853{
1854	int error;
1855
1856	AUDIT_ARG_SVIPC_WHICH(uap->which);
1857	if (uap->which < 0 || uap->which >= nitems(msgcalls))
1858		return (EINVAL);
1859	error = (*msgcalls[uap->which])(td, &uap->a2);
1860	return (error);
1861}
1862
1863#ifndef CP
1864#define CP(src, dst, fld)	do { (dst).fld = (src).fld; } while (0)
1865#endif
1866
1867#ifndef _SYS_SYSPROTO_H_
1868struct freebsd7_msgctl_args {
1869	int	msqid;
1870	int	cmd;
1871	struct	msqid_ds_old *buf;
1872};
1873#endif
1874int
1875freebsd7_msgctl(struct thread *td, struct freebsd7_msgctl_args *uap)
1876{
1877	struct msqid_ds_old msqold;
1878	struct msqid_ds msqbuf;
1879	int error;
1880
1881	DPRINTF(("call to freebsd7_msgctl(%d, %d, %p)\n", uap->msqid, uap->cmd,
1882	    uap->buf));
1883	if (uap->cmd == IPC_SET) {
1884		error = copyin(uap->buf, &msqold, sizeof(msqold));
1885		if (error)
1886			return (error);
1887		ipcperm_old2new(&msqold.msg_perm, &msqbuf.msg_perm);
1888		CP(msqold, msqbuf, __msg_first);
1889		CP(msqold, msqbuf, __msg_last);
1890		CP(msqold, msqbuf, msg_cbytes);
1891		CP(msqold, msqbuf, msg_qnum);
1892		CP(msqold, msqbuf, msg_qbytes);
1893		CP(msqold, msqbuf, msg_lspid);
1894		CP(msqold, msqbuf, msg_lrpid);
1895		CP(msqold, msqbuf, msg_stime);
1896		CP(msqold, msqbuf, msg_rtime);
1897		CP(msqold, msqbuf, msg_ctime);
1898	}
1899	error = kern_msgctl(td, uap->msqid, uap->cmd, &msqbuf);
1900	if (error)
1901		return (error);
1902	if (uap->cmd == IPC_STAT) {
1903		bzero(&msqold, sizeof(msqold));
1904		ipcperm_new2old(&msqbuf.msg_perm, &msqold.msg_perm);
1905		CP(msqbuf, msqold, __msg_first);
1906		CP(msqbuf, msqold, __msg_last);
1907		CP(msqbuf, msqold, msg_cbytes);
1908		CP(msqbuf, msqold, msg_qnum);
1909		CP(msqbuf, msqold, msg_qbytes);
1910		CP(msqbuf, msqold, msg_lspid);
1911		CP(msqbuf, msqold, msg_lrpid);
1912		CP(msqbuf, msqold, msg_stime);
1913		CP(msqbuf, msqold, msg_rtime);
1914		CP(msqbuf, msqold, msg_ctime);
1915		error = copyout(&msqold, uap->buf, sizeof(struct msqid_ds_old));
1916	}
1917	return (error);
1918}
1919
1920#undef CP
1921
1922#endif	/* COMPAT_FREEBSD4 || COMPAT_FREEBSD5 || COMPAT_FREEBSD6 ||
1923	   COMPAT_FREEBSD7 */
1924