1/*-
2 * SPDX-License-Identifier: BSD-2-Clause-FreeBSD
3 *
4 * Copyright (c) 2008-2010 Edward Tomasz Napiera��a <trasz@FreeBSD.org>
5 *
6 * Redistribution and use in source and binary forms, with or without
7 * modification, are permitted provided that the following conditions
8 * are met:
9 * 1. Redistributions of source code must retain the above copyright
10 *    notice, this list of conditions and the following disclaimer.
11 * 2. Redistributions in binary form must reproduce the above copyright
12 *    notice, this list of conditions and the following disclaimer in the
13 *    documentation and/or other materials provided with the distribution.
14 *
15 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
16 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
17 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
18 * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
19 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
20 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
21 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
22 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
23 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
24 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
25 * SUCH DAMAGE.
26 */
27
28/*
29 * ACL support routines specific to NFSv4 access control lists.  These are
30 * utility routines for code common across file systems implementing NFSv4
31 * ACLs.
32 */
33
34#ifdef _KERNEL
35#include <sys/cdefs.h>
36__FBSDID("$FreeBSD$");
37
38#include <sys/param.h>
39#include <sys/kernel.h>
40#include <sys/module.h>
41#include <sys/systm.h>
42#include <sys/mount.h>
43#include <sys/priv.h>
44#include <sys/vnode.h>
45#include <sys/errno.h>
46#include <sys/stat.h>
47#include <sys/sysctl.h>
48#include <sys/acl.h>
49#else
50#include <errno.h>
51#include <assert.h>
52#include <sys/acl.h>
53#include <sys/stat.h>
54#define KASSERT(a, b) assert(a)
55#define CTASSERT(a)
56
57#endif /* !_KERNEL */
58
59#ifdef _KERNEL
60
61static void	acl_nfs4_trivial_from_mode(struct acl *aclp, mode_t mode);
62
63static int	acl_nfs4_old_semantics = 0;
64
65SYSCTL_INT(_vfs, OID_AUTO, acl_nfs4_old_semantics, CTLFLAG_RW,
66    &acl_nfs4_old_semantics, 0, "Use pre-PSARC/2010/029 NFSv4 ACL semantics");
67
68static struct {
69	accmode_t accmode;
70	int mask;
71} accmode2mask[] = {{VREAD, ACL_READ_DATA},
72		    {VWRITE, ACL_WRITE_DATA},
73		    {VAPPEND, ACL_APPEND_DATA},
74		    {VEXEC, ACL_EXECUTE},
75		    {VREAD_NAMED_ATTRS, ACL_READ_NAMED_ATTRS},
76		    {VWRITE_NAMED_ATTRS, ACL_WRITE_NAMED_ATTRS},
77		    {VDELETE_CHILD, ACL_DELETE_CHILD},
78		    {VREAD_ATTRIBUTES, ACL_READ_ATTRIBUTES},
79		    {VWRITE_ATTRIBUTES, ACL_WRITE_ATTRIBUTES},
80		    {VDELETE, ACL_DELETE},
81		    {VREAD_ACL, ACL_READ_ACL},
82		    {VWRITE_ACL, ACL_WRITE_ACL},
83		    {VWRITE_OWNER, ACL_WRITE_OWNER},
84		    {VSYNCHRONIZE, ACL_SYNCHRONIZE},
85		    {0, 0}};
86
87static int
88_access_mask_from_accmode(accmode_t accmode)
89{
90	int access_mask = 0, i;
91
92	for (i = 0; accmode2mask[i].accmode != 0; i++) {
93		if (accmode & accmode2mask[i].accmode)
94			access_mask |= accmode2mask[i].mask;
95	}
96
97	/*
98	 * VAPPEND is just a modifier for VWRITE; if the caller asked
99	 * for 'VAPPEND | VWRITE', we want to check for ACL_APPEND_DATA only.
100	 */
101	if (access_mask & ACL_APPEND_DATA)
102		access_mask &= ~ACL_WRITE_DATA;
103
104	return (access_mask);
105}
106
107/*
108 * Return 0, iff access is allowed, 1 otherwise.
109 */
110static int
111_acl_denies(const struct acl *aclp, int access_mask, struct ucred *cred,
112    int file_uid, int file_gid, int *denied_explicitly)
113{
114	int i;
115	const struct acl_entry *entry;
116
117	if (denied_explicitly != NULL)
118		*denied_explicitly = 0;
119
120	KASSERT(aclp->acl_cnt <= ACL_MAX_ENTRIES,
121	    ("aclp->acl_cnt <= ACL_MAX_ENTRIES"));
122
123	for (i = 0; i < aclp->acl_cnt; i++) {
124		entry = &(aclp->acl_entry[i]);
125
126		if (entry->ae_entry_type != ACL_ENTRY_TYPE_ALLOW &&
127		    entry->ae_entry_type != ACL_ENTRY_TYPE_DENY)
128			continue;
129		if (entry->ae_flags & ACL_ENTRY_INHERIT_ONLY)
130			continue;
131		switch (entry->ae_tag) {
132		case ACL_USER_OBJ:
133			if (file_uid != cred->cr_uid)
134				continue;
135			break;
136		case ACL_USER:
137			if (entry->ae_id != cred->cr_uid)
138				continue;
139			break;
140		case ACL_GROUP_OBJ:
141			if (!groupmember(file_gid, cred))
142				continue;
143			break;
144		case ACL_GROUP:
145			if (!groupmember(entry->ae_id, cred))
146				continue;
147			break;
148		default:
149			KASSERT(entry->ae_tag == ACL_EVERYONE,
150			    ("entry->ae_tag == ACL_EVERYONE"));
151		}
152
153		if (entry->ae_entry_type == ACL_ENTRY_TYPE_DENY) {
154			if (entry->ae_perm & access_mask) {
155				if (denied_explicitly != NULL)
156					*denied_explicitly = 1;
157				return (1);
158			}
159		}
160
161		access_mask &= ~(entry->ae_perm);
162		if (access_mask == 0)
163			return (0);
164	}
165
166	if (access_mask == 0)
167		return (0);
168
169	return (1);
170}
171
172int
173vaccess_acl_nfs4(enum vtype type, uid_t file_uid, gid_t file_gid,
174    struct acl *aclp, accmode_t accmode, struct ucred *cred)
175{
176	accmode_t priv_granted = 0;
177	int denied, explicitly_denied, access_mask, is_directory,
178	    must_be_owner = 0;
179	mode_t file_mode = 0;
180
181	KASSERT((accmode & ~(VEXEC | VWRITE | VREAD | VADMIN | VAPPEND |
182	    VEXPLICIT_DENY | VREAD_NAMED_ATTRS | VWRITE_NAMED_ATTRS |
183	    VDELETE_CHILD | VREAD_ATTRIBUTES | VWRITE_ATTRIBUTES | VDELETE |
184	    VREAD_ACL | VWRITE_ACL | VWRITE_OWNER | VSYNCHRONIZE)) == 0,
185	    ("invalid bit in accmode"));
186	KASSERT((accmode & VAPPEND) == 0 || (accmode & VWRITE),
187	    	("VAPPEND without VWRITE"));
188
189	if (accmode & VADMIN)
190		must_be_owner = 1;
191
192	/*
193	 * Ignore VSYNCHRONIZE permission.
194	 */
195	accmode &= ~VSYNCHRONIZE;
196
197	access_mask = _access_mask_from_accmode(accmode);
198
199	if (type == VDIR)
200		is_directory = 1;
201	else
202		is_directory = 0;
203
204	/*
205	 * File owner is always allowed to read and write the ACL
206	 * and basic attributes.  This is to prevent a situation
207	 * where user would change ACL in a way that prevents him
208	 * from undoing the change.
209	 */
210	if (file_uid == cred->cr_uid)
211		access_mask &= ~(ACL_READ_ACL | ACL_WRITE_ACL |
212		    ACL_READ_ATTRIBUTES | ACL_WRITE_ATTRIBUTES);
213
214	/*
215	 * Ignore append permission for regular files; use write
216	 * permission instead.
217	 */
218	if (!is_directory && (access_mask & ACL_APPEND_DATA)) {
219		access_mask &= ~ACL_APPEND_DATA;
220		access_mask |= ACL_WRITE_DATA;
221	}
222
223	denied = _acl_denies(aclp, access_mask, cred, file_uid, file_gid,
224	    &explicitly_denied);
225
226	if (must_be_owner) {
227		if (file_uid != cred->cr_uid)
228			denied = EPERM;
229	}
230
231	/*
232	 * For VEXEC, ensure that at least one execute bit is set for
233	 * non-directories. We have to check the mode here to stay
234	 * consistent with execve(2). See the test in
235	 * exec_check_permissions().
236	 */
237	acl_nfs4_sync_mode_from_acl(&file_mode, aclp);
238	if (!denied && !is_directory && (accmode & VEXEC) &&
239	    (file_mode & (S_IXUSR | S_IXGRP | S_IXOTH)) == 0)
240		denied = EACCES;
241
242	if (!denied)
243		return (0);
244
245	/*
246	 * Access failed.  Iff it was not denied explicitly and
247	 * VEXPLICIT_DENY flag was specified, allow access.
248	 */
249	if ((accmode & VEXPLICIT_DENY) && explicitly_denied == 0)
250		return (0);
251
252	accmode &= ~VEXPLICIT_DENY;
253
254	/*
255	 * No match.  Try to use privileges, if there are any.
256	 */
257	if (is_directory) {
258		if ((accmode & VEXEC) && !priv_check_cred(cred, PRIV_VFS_LOOKUP))
259			priv_granted |= VEXEC;
260	} else {
261		/*
262		 * Ensure that at least one execute bit is on. Otherwise,
263		 * a privileged user will always succeed, and we don't want
264		 * this to happen unless the file really is executable.
265		 */
266		if ((accmode & VEXEC) && (file_mode &
267		    (S_IXUSR | S_IXGRP | S_IXOTH)) != 0 &&
268		    !priv_check_cred(cred, PRIV_VFS_EXEC))
269			priv_granted |= VEXEC;
270	}
271
272	if ((accmode & VREAD) && !priv_check_cred(cred, PRIV_VFS_READ))
273		priv_granted |= VREAD;
274
275	if ((accmode & (VWRITE | VAPPEND | VDELETE_CHILD)) &&
276	    !priv_check_cred(cred, PRIV_VFS_WRITE))
277		priv_granted |= (VWRITE | VAPPEND | VDELETE_CHILD);
278
279	if ((accmode & VADMIN_PERMS) &&
280	    !priv_check_cred(cred, PRIV_VFS_ADMIN))
281		priv_granted |= VADMIN_PERMS;
282
283	if ((accmode & VSTAT_PERMS) &&
284	    !priv_check_cred(cred, PRIV_VFS_STAT))
285		priv_granted |= VSTAT_PERMS;
286
287	if ((accmode & priv_granted) == accmode) {
288		return (0);
289	}
290
291	if (accmode & (VADMIN_PERMS | VDELETE_CHILD | VDELETE))
292		denied = EPERM;
293	else
294		denied = EACCES;
295
296	return (denied);
297}
298#endif /* _KERNEL */
299
300static int
301_acl_entry_matches(struct acl_entry *entry, acl_tag_t tag, acl_perm_t perm,
302    acl_entry_type_t entry_type)
303{
304	if (entry->ae_tag != tag)
305		return (0);
306
307	if (entry->ae_id != ACL_UNDEFINED_ID)
308		return (0);
309
310	if (entry->ae_perm != perm)
311		return (0);
312
313	if (entry->ae_entry_type != entry_type)
314		return (0);
315
316	if (entry->ae_flags != 0)
317		return (0);
318
319	return (1);
320}
321
322static struct acl_entry *
323_acl_append(struct acl *aclp, acl_tag_t tag, acl_perm_t perm,
324    acl_entry_type_t entry_type)
325{
326	struct acl_entry *entry;
327
328	KASSERT(aclp->acl_cnt + 1 <= ACL_MAX_ENTRIES,
329	    ("aclp->acl_cnt + 1 <= ACL_MAX_ENTRIES"));
330
331	entry = &(aclp->acl_entry[aclp->acl_cnt]);
332	aclp->acl_cnt++;
333
334	entry->ae_tag = tag;
335	entry->ae_id = ACL_UNDEFINED_ID;
336	entry->ae_perm = perm;
337	entry->ae_entry_type = entry_type;
338	entry->ae_flags = 0;
339
340	return (entry);
341}
342
343static struct acl_entry *
344_acl_duplicate_entry(struct acl *aclp, unsigned entry_index)
345{
346	unsigned i;
347
348	KASSERT(aclp->acl_cnt + 1 <= ACL_MAX_ENTRIES,
349	    ("aclp->acl_cnt + 1 <= ACL_MAX_ENTRIES"));
350
351	for (i = aclp->acl_cnt; i > entry_index; i--)
352		aclp->acl_entry[i] = aclp->acl_entry[i - 1];
353
354	aclp->acl_cnt++;
355
356	return (&(aclp->acl_entry[entry_index + 1]));
357}
358
359static void
360acl_nfs4_sync_acl_from_mode_draft(struct acl *aclp, mode_t mode,
361    int file_owner_id)
362{
363	int meets, must_append;
364	unsigned i;
365	struct acl_entry *entry, *copy, *previous,
366	    *a1, *a2, *a3, *a4, *a5, *a6;
367	mode_t amode;
368	const int READ = 04;
369	const int WRITE = 02;
370	const int EXEC = 01;
371
372	KASSERT(aclp->acl_cnt <= ACL_MAX_ENTRIES,
373	    ("aclp->acl_cnt <= ACL_MAX_ENTRIES"));
374
375	/*
376	 * NFSv4 Minor Version 1, draft-ietf-nfsv4-minorversion1-03.txt
377	 *
378	 * 3.16.6.3. Applying a Mode to an Existing ACL
379	 */
380
381	/*
382	 * 1. For each ACE:
383	 */
384	for (i = 0; i < aclp->acl_cnt; i++) {
385		entry = &(aclp->acl_entry[i]);
386
387		/*
388		 * 1.1. If the type is neither ALLOW or DENY - skip.
389		 */
390		if (entry->ae_entry_type != ACL_ENTRY_TYPE_ALLOW &&
391		    entry->ae_entry_type != ACL_ENTRY_TYPE_DENY)
392			continue;
393
394		/*
395		 * 1.2. If ACL_ENTRY_INHERIT_ONLY is set - skip.
396		 */
397		if (entry->ae_flags & ACL_ENTRY_INHERIT_ONLY)
398			continue;
399
400		/*
401		 * 1.3. If ACL_ENTRY_FILE_INHERIT or ACL_ENTRY_DIRECTORY_INHERIT
402		 *      are set:
403		 */
404		if (entry->ae_flags &
405		    (ACL_ENTRY_FILE_INHERIT | ACL_ENTRY_DIRECTORY_INHERIT)) {
406			/*
407			 * 1.3.1. A copy of the current ACE is made, and placed
408			 *        in the ACL immediately following the current
409			 *        ACE.
410			 */
411			copy = _acl_duplicate_entry(aclp, i);
412
413			/*
414			 * 1.3.2. In the first ACE, the flag
415			 *        ACL_ENTRY_INHERIT_ONLY is set.
416			 */
417			entry->ae_flags |= ACL_ENTRY_INHERIT_ONLY;
418
419			/*
420			 * 1.3.3. In the second ACE, the following flags
421			 *        are cleared:
422			 *        ACL_ENTRY_FILE_INHERIT,
423			 *        ACL_ENTRY_DIRECTORY_INHERIT,
424			 *        ACL_ENTRY_NO_PROPAGATE_INHERIT.
425			 */
426			copy->ae_flags &= ~(ACL_ENTRY_FILE_INHERIT |
427			    ACL_ENTRY_DIRECTORY_INHERIT |
428			    ACL_ENTRY_NO_PROPAGATE_INHERIT);
429
430			/*
431			 * The algorithm continues on with the second ACE.
432			 */
433			i++;
434			entry = copy;
435		}
436
437		/*
438		 * 1.4. If it's owner@, group@ or everyone@ entry, clear
439		 *      ACL_READ_DATA, ACL_WRITE_DATA, ACL_APPEND_DATA
440		 *      and ACL_EXECUTE.  Continue to the next entry.
441		 */
442		if (entry->ae_tag == ACL_USER_OBJ ||
443		    entry->ae_tag == ACL_GROUP_OBJ ||
444		    entry->ae_tag == ACL_EVERYONE) {
445			entry->ae_perm &= ~(ACL_READ_DATA | ACL_WRITE_DATA |
446			    ACL_APPEND_DATA | ACL_EXECUTE);
447			continue;
448		}
449
450		/*
451		 * 1.5. Otherwise, if the "who" field did not match one
452		 *      of OWNER@, GROUP@, EVERYONE@:
453		 *
454		 * 1.5.1. If the type is ALLOW, check the preceding ACE.
455		 *        If it does not meet all of the following criteria:
456		 */
457		if (entry->ae_entry_type != ACL_ENTRY_TYPE_ALLOW)
458			continue;
459
460		meets = 0;
461		if (i > 0) {
462			meets = 1;
463			previous = &(aclp->acl_entry[i - 1]);
464
465			/*
466			 * 1.5.1.1. The type field is DENY,
467			 */
468			if (previous->ae_entry_type != ACL_ENTRY_TYPE_DENY)
469				meets = 0;
470
471			/*
472			 * 1.5.1.2. The "who" field is the same as the current
473			 *          ACE,
474			 *
475			 * 1.5.1.3. The flag bit ACE4_IDENTIFIER_GROUP
476			 *          is the same as it is in the current ACE,
477			 *          and no other flag bits are set,
478			 */
479			if (previous->ae_id != entry->ae_id ||
480			    previous->ae_tag != entry->ae_tag)
481				meets = 0;
482
483			if (previous->ae_flags)
484				meets = 0;
485
486			/*
487			 * 1.5.1.4. The mask bits are a subset of the mask bits
488			 *          of the current ACE, and are also subset of
489			 *          the following: ACL_READ_DATA,
490			 *          ACL_WRITE_DATA, ACL_APPEND_DATA, ACL_EXECUTE
491			 */
492			if (previous->ae_perm & ~(entry->ae_perm))
493				meets = 0;
494
495			if (previous->ae_perm & ~(ACL_READ_DATA |
496			    ACL_WRITE_DATA | ACL_APPEND_DATA | ACL_EXECUTE))
497				meets = 0;
498		}
499
500		if (!meets) {
501			/*
502		 	 * Then the ACE of type DENY, with a who equal
503			 * to the current ACE, flag bits equal to
504			 * (<current ACE flags> & <ACE_IDENTIFIER_GROUP>)
505			 * and no mask bits, is prepended.
506			 */
507			previous = entry;
508			entry = _acl_duplicate_entry(aclp, i);
509
510			/* Adjust counter, as we've just added an entry. */
511			i++;
512
513			previous->ae_tag = entry->ae_tag;
514			previous->ae_id = entry->ae_id;
515			previous->ae_flags = entry->ae_flags;
516			previous->ae_perm = 0;
517			previous->ae_entry_type = ACL_ENTRY_TYPE_DENY;
518		}
519
520		/*
521		 * 1.5.2. The following modifications are made to the prepended
522		 *        ACE.  The intent is to mask the following ACE
523		 *        to disallow ACL_READ_DATA, ACL_WRITE_DATA,
524		 *        ACL_APPEND_DATA, or ACL_EXECUTE, based upon the group
525		 *        permissions of the new mode.  As a special case,
526		 *        if the ACE matches the current owner of the file,
527		 *        the owner bits are used, rather than the group bits.
528		 *        This is reflected in the algorithm below.
529		 */
530		amode = mode >> 3;
531
532		/*
533		 * If ACE4_IDENTIFIER_GROUP is not set, and the "who" field
534		 * in ACE matches the owner of the file, we shift amode three
535		 * more bits, in order to have the owner permission bits
536		 * placed in the three low order bits of amode.
537		 */
538		if (entry->ae_tag == ACL_USER && entry->ae_id == file_owner_id)
539			amode = amode >> 3;
540
541		if (entry->ae_perm & ACL_READ_DATA) {
542			if (amode & READ)
543				previous->ae_perm &= ~ACL_READ_DATA;
544			else
545				previous->ae_perm |= ACL_READ_DATA;
546		}
547
548		if (entry->ae_perm & ACL_WRITE_DATA) {
549			if (amode & WRITE)
550				previous->ae_perm &= ~ACL_WRITE_DATA;
551			else
552				previous->ae_perm |= ACL_WRITE_DATA;
553		}
554
555		if (entry->ae_perm & ACL_APPEND_DATA) {
556			if (amode & WRITE)
557				previous->ae_perm &= ~ACL_APPEND_DATA;
558			else
559				previous->ae_perm |= ACL_APPEND_DATA;
560		}
561
562		if (entry->ae_perm & ACL_EXECUTE) {
563			if (amode & EXEC)
564				previous->ae_perm &= ~ACL_EXECUTE;
565			else
566				previous->ae_perm |= ACL_EXECUTE;
567		}
568
569		/*
570		 * 1.5.3. If ACE4_IDENTIFIER_GROUP is set in the flags
571		 *        of the ALLOW ace:
572		 *
573		 * XXX: This point is not there in the Falkner's draft.
574		 */
575		if (entry->ae_tag == ACL_GROUP &&
576		    entry->ae_entry_type == ACL_ENTRY_TYPE_ALLOW) {
577			mode_t extramode, ownermode;
578			extramode = (mode >> 3) & 07;
579			ownermode = mode >> 6;
580			extramode &= ~ownermode;
581
582			if (extramode) {
583				if (extramode & READ) {
584					entry->ae_perm &= ~ACL_READ_DATA;
585					previous->ae_perm &= ~ACL_READ_DATA;
586				}
587
588				if (extramode & WRITE) {
589					entry->ae_perm &=
590					    ~(ACL_WRITE_DATA | ACL_APPEND_DATA);
591					previous->ae_perm &=
592					    ~(ACL_WRITE_DATA | ACL_APPEND_DATA);
593				}
594
595				if (extramode & EXEC) {
596					entry->ae_perm &= ~ACL_EXECUTE;
597					previous->ae_perm &= ~ACL_EXECUTE;
598				}
599			}
600		}
601	}
602
603	/*
604	 * 2. If there at least six ACEs, the final six ACEs are examined.
605	 *    If they are not equal to what we want, append six ACEs.
606	 */
607	must_append = 0;
608	if (aclp->acl_cnt < 6) {
609		must_append = 1;
610	} else {
611		a6 = &(aclp->acl_entry[aclp->acl_cnt - 1]);
612		a5 = &(aclp->acl_entry[aclp->acl_cnt - 2]);
613		a4 = &(aclp->acl_entry[aclp->acl_cnt - 3]);
614		a3 = &(aclp->acl_entry[aclp->acl_cnt - 4]);
615		a2 = &(aclp->acl_entry[aclp->acl_cnt - 5]);
616		a1 = &(aclp->acl_entry[aclp->acl_cnt - 6]);
617
618		if (!_acl_entry_matches(a1, ACL_USER_OBJ, 0,
619		    ACL_ENTRY_TYPE_DENY))
620			must_append = 1;
621		if (!_acl_entry_matches(a2, ACL_USER_OBJ, ACL_WRITE_ACL |
622		    ACL_WRITE_OWNER | ACL_WRITE_ATTRIBUTES |
623		    ACL_WRITE_NAMED_ATTRS, ACL_ENTRY_TYPE_ALLOW))
624			must_append = 1;
625		if (!_acl_entry_matches(a3, ACL_GROUP_OBJ, 0,
626		    ACL_ENTRY_TYPE_DENY))
627			must_append = 1;
628		if (!_acl_entry_matches(a4, ACL_GROUP_OBJ, 0,
629		    ACL_ENTRY_TYPE_ALLOW))
630			must_append = 1;
631		if (!_acl_entry_matches(a5, ACL_EVERYONE, ACL_WRITE_ACL |
632		    ACL_WRITE_OWNER | ACL_WRITE_ATTRIBUTES |
633		    ACL_WRITE_NAMED_ATTRS, ACL_ENTRY_TYPE_DENY))
634			must_append = 1;
635		if (!_acl_entry_matches(a6, ACL_EVERYONE, ACL_READ_ACL |
636		    ACL_READ_ATTRIBUTES | ACL_READ_NAMED_ATTRS |
637		    ACL_SYNCHRONIZE, ACL_ENTRY_TYPE_ALLOW))
638			must_append = 1;
639	}
640
641	if (must_append) {
642		KASSERT(aclp->acl_cnt + 6 <= ACL_MAX_ENTRIES,
643		    ("aclp->acl_cnt <= ACL_MAX_ENTRIES"));
644
645		a1 = _acl_append(aclp, ACL_USER_OBJ, 0, ACL_ENTRY_TYPE_DENY);
646		a2 = _acl_append(aclp, ACL_USER_OBJ, ACL_WRITE_ACL |
647		    ACL_WRITE_OWNER | ACL_WRITE_ATTRIBUTES |
648		    ACL_WRITE_NAMED_ATTRS, ACL_ENTRY_TYPE_ALLOW);
649		a3 = _acl_append(aclp, ACL_GROUP_OBJ, 0, ACL_ENTRY_TYPE_DENY);
650		a4 = _acl_append(aclp, ACL_GROUP_OBJ, 0, ACL_ENTRY_TYPE_ALLOW);
651		a5 = _acl_append(aclp, ACL_EVERYONE, ACL_WRITE_ACL |
652		    ACL_WRITE_OWNER | ACL_WRITE_ATTRIBUTES |
653		    ACL_WRITE_NAMED_ATTRS, ACL_ENTRY_TYPE_DENY);
654		a6 = _acl_append(aclp, ACL_EVERYONE, ACL_READ_ACL |
655		    ACL_READ_ATTRIBUTES | ACL_READ_NAMED_ATTRS |
656		    ACL_SYNCHRONIZE, ACL_ENTRY_TYPE_ALLOW);
657
658		KASSERT(a1 != NULL && a2 != NULL && a3 != NULL && a4 != NULL &&
659		    a5 != NULL && a6 != NULL, ("couldn't append to ACL."));
660	}
661
662	/*
663	 * 3. The final six ACEs are adjusted according to the incoming mode.
664	 */
665	if (mode & S_IRUSR)
666		a2->ae_perm |= ACL_READ_DATA;
667	else
668		a1->ae_perm |= ACL_READ_DATA;
669	if (mode & S_IWUSR)
670		a2->ae_perm |= (ACL_WRITE_DATA | ACL_APPEND_DATA);
671	else
672		a1->ae_perm |= (ACL_WRITE_DATA | ACL_APPEND_DATA);
673	if (mode & S_IXUSR)
674		a2->ae_perm |= ACL_EXECUTE;
675	else
676		a1->ae_perm |= ACL_EXECUTE;
677
678	if (mode & S_IRGRP)
679		a4->ae_perm |= ACL_READ_DATA;
680	else
681		a3->ae_perm |= ACL_READ_DATA;
682	if (mode & S_IWGRP)
683		a4->ae_perm |= (ACL_WRITE_DATA | ACL_APPEND_DATA);
684	else
685		a3->ae_perm |= (ACL_WRITE_DATA | ACL_APPEND_DATA);
686	if (mode & S_IXGRP)
687		a4->ae_perm |= ACL_EXECUTE;
688	else
689		a3->ae_perm |= ACL_EXECUTE;
690
691	if (mode & S_IROTH)
692		a6->ae_perm |= ACL_READ_DATA;
693	else
694		a5->ae_perm |= ACL_READ_DATA;
695	if (mode & S_IWOTH)
696		a6->ae_perm |= (ACL_WRITE_DATA | ACL_APPEND_DATA);
697	else
698		a5->ae_perm |= (ACL_WRITE_DATA | ACL_APPEND_DATA);
699	if (mode & S_IXOTH)
700		a6->ae_perm |= ACL_EXECUTE;
701	else
702		a5->ae_perm |= ACL_EXECUTE;
703}
704
705#ifdef _KERNEL
706void
707acl_nfs4_sync_acl_from_mode(struct acl *aclp, mode_t mode,
708    int file_owner_id)
709{
710
711	if (acl_nfs4_old_semantics)
712		acl_nfs4_sync_acl_from_mode_draft(aclp, mode, file_owner_id);
713	else
714		acl_nfs4_trivial_from_mode(aclp, mode);
715}
716#endif /* _KERNEL */
717
718void
719acl_nfs4_sync_mode_from_acl(mode_t *_mode, const struct acl *aclp)
720{
721	int i;
722	mode_t old_mode = *_mode, mode = 0, seen = 0;
723	const struct acl_entry *entry;
724
725	KASSERT(aclp->acl_cnt <= ACL_MAX_ENTRIES,
726	    ("aclp->acl_cnt <= ACL_MAX_ENTRIES"));
727
728	/*
729	 * NFSv4 Minor Version 1, draft-ietf-nfsv4-minorversion1-03.txt
730	 *
731	 * 3.16.6.1. Recomputing mode upon SETATTR of ACL
732	 */
733
734	for (i = 0; i < aclp->acl_cnt; i++) {
735		entry = &(aclp->acl_entry[i]);
736
737		if (entry->ae_entry_type != ACL_ENTRY_TYPE_ALLOW &&
738		    entry->ae_entry_type != ACL_ENTRY_TYPE_DENY)
739			continue;
740
741		if (entry->ae_flags & ACL_ENTRY_INHERIT_ONLY)
742			continue;
743
744		if (entry->ae_tag == ACL_USER_OBJ) {
745			if ((entry->ae_perm & ACL_READ_DATA) &&
746			    ((seen & S_IRUSR) == 0)) {
747				seen |= S_IRUSR;
748				if (entry->ae_entry_type == ACL_ENTRY_TYPE_ALLOW)
749					mode |= S_IRUSR;
750			}
751			if ((entry->ae_perm & ACL_WRITE_DATA) &&
752			     ((seen & S_IWUSR) == 0)) {
753				seen |= S_IWUSR;
754				if (entry->ae_entry_type == ACL_ENTRY_TYPE_ALLOW)
755					mode |= S_IWUSR;
756			}
757			if ((entry->ae_perm & ACL_EXECUTE) &&
758			    ((seen & S_IXUSR) == 0)) {
759				seen |= S_IXUSR;
760				if (entry->ae_entry_type == ACL_ENTRY_TYPE_ALLOW)
761					mode |= S_IXUSR;
762			}
763		} else if (entry->ae_tag == ACL_GROUP_OBJ) {
764			if ((entry->ae_perm & ACL_READ_DATA) &&
765			    ((seen & S_IRGRP) == 0)) {
766				seen |= S_IRGRP;
767				if (entry->ae_entry_type == ACL_ENTRY_TYPE_ALLOW)
768					mode |= S_IRGRP;
769			}
770			if ((entry->ae_perm & ACL_WRITE_DATA) &&
771			    ((seen & S_IWGRP) == 0)) {
772				seen |= S_IWGRP;
773				if (entry->ae_entry_type == ACL_ENTRY_TYPE_ALLOW)
774					mode |= S_IWGRP;
775			}
776			if ((entry->ae_perm & ACL_EXECUTE) &&
777			    ((seen & S_IXGRP) == 0)) {
778				seen |= S_IXGRP;
779				if (entry->ae_entry_type == ACL_ENTRY_TYPE_ALLOW)
780					mode |= S_IXGRP;
781			}
782		} else if (entry->ae_tag == ACL_EVERYONE) {
783			if (entry->ae_perm & ACL_READ_DATA) {
784				if ((seen & S_IRUSR) == 0) {
785					seen |= S_IRUSR;
786					if (entry->ae_entry_type == ACL_ENTRY_TYPE_ALLOW)
787						mode |= S_IRUSR;
788				}
789				if ((seen & S_IRGRP) == 0) {
790					seen |= S_IRGRP;
791					if (entry->ae_entry_type == ACL_ENTRY_TYPE_ALLOW)
792						mode |= S_IRGRP;
793				}
794				if ((seen & S_IROTH) == 0) {
795					seen |= S_IROTH;
796					if (entry->ae_entry_type == ACL_ENTRY_TYPE_ALLOW)
797						mode |= S_IROTH;
798				}
799			}
800			if (entry->ae_perm & ACL_WRITE_DATA) {
801				if ((seen & S_IWUSR) == 0) {
802					seen |= S_IWUSR;
803					if (entry->ae_entry_type == ACL_ENTRY_TYPE_ALLOW)
804						mode |= S_IWUSR;
805				}
806				if ((seen & S_IWGRP) == 0) {
807					seen |= S_IWGRP;
808					if (entry->ae_entry_type == ACL_ENTRY_TYPE_ALLOW)
809						mode |= S_IWGRP;
810				}
811				if ((seen & S_IWOTH) == 0) {
812					seen |= S_IWOTH;
813					if (entry->ae_entry_type == ACL_ENTRY_TYPE_ALLOW)
814						mode |= S_IWOTH;
815				}
816			}
817			if (entry->ae_perm & ACL_EXECUTE) {
818				if ((seen & S_IXUSR) == 0) {
819					seen |= S_IXUSR;
820					if (entry->ae_entry_type == ACL_ENTRY_TYPE_ALLOW)
821						mode |= S_IXUSR;
822				}
823				if ((seen & S_IXGRP) == 0) {
824					seen |= S_IXGRP;
825					if (entry->ae_entry_type == ACL_ENTRY_TYPE_ALLOW)
826						mode |= S_IXGRP;
827				}
828				if ((seen & S_IXOTH) == 0) {
829					seen |= S_IXOTH;
830					if (entry->ae_entry_type == ACL_ENTRY_TYPE_ALLOW)
831						mode |= S_IXOTH;
832				}
833			}
834		}
835	}
836
837	*_mode = mode | (old_mode & ACL_PRESERVE_MASK);
838}
839
840#ifdef _KERNEL
841/*
842 * Calculate inherited ACL in a manner compatible with NFSv4 Minor Version 1,
843 * draft-ietf-nfsv4-minorversion1-03.txt.
844 */
845static void
846acl_nfs4_compute_inherited_acl_draft(const struct acl *parent_aclp,
847    struct acl *child_aclp, mode_t mode, int file_owner_id,
848    int is_directory)
849{
850	int i, flags;
851	const struct acl_entry *parent_entry;
852	struct acl_entry *entry, *copy;
853
854	KASSERT(child_aclp->acl_cnt == 0, ("child_aclp->acl_cnt == 0"));
855	KASSERT(parent_aclp->acl_cnt <= ACL_MAX_ENTRIES,
856	    ("parent_aclp->acl_cnt <= ACL_MAX_ENTRIES"));
857
858	/*
859	 * NFSv4 Minor Version 1, draft-ietf-nfsv4-minorversion1-03.txt
860	 *
861	 * 3.16.6.2. Applying the mode given to CREATE or OPEN
862	 *           to an inherited ACL
863	 */
864
865	/*
866	 * 1. Form an ACL that is the concatenation of all inheritable ACEs.
867	 */
868	for (i = 0; i < parent_aclp->acl_cnt; i++) {
869		parent_entry = &(parent_aclp->acl_entry[i]);
870		flags = parent_entry->ae_flags;
871
872		/*
873		 * Entry is not inheritable at all.
874		 */
875		if ((flags & (ACL_ENTRY_DIRECTORY_INHERIT |
876		    ACL_ENTRY_FILE_INHERIT)) == 0)
877			continue;
878
879		/*
880		 * We're creating a file, but entry is not inheritable
881		 * by files.
882		 */
883		if (!is_directory && (flags & ACL_ENTRY_FILE_INHERIT) == 0)
884			continue;
885
886		/*
887		 * Entry is inheritable only by files, but has NO_PROPAGATE
888		 * flag set, and we're creating a directory, so it wouldn't
889		 * propagate to any file in that directory anyway.
890		 */
891		if (is_directory &&
892		    (flags & ACL_ENTRY_DIRECTORY_INHERIT) == 0 &&
893		    (flags & ACL_ENTRY_NO_PROPAGATE_INHERIT))
894			continue;
895
896		KASSERT(child_aclp->acl_cnt + 1 <= ACL_MAX_ENTRIES,
897		    ("child_aclp->acl_cnt + 1 <= ACL_MAX_ENTRIES"));
898		child_aclp->acl_entry[child_aclp->acl_cnt] = *parent_entry;
899		child_aclp->acl_cnt++;
900	}
901
902	/*
903	 * 2. For each entry in the new ACL, adjust its flags, possibly
904	 *    creating two entries in place of one.
905	 */
906	for (i = 0; i < child_aclp->acl_cnt; i++) {
907		entry = &(child_aclp->acl_entry[i]);
908
909		/*
910		 * This is not in the specification, but SunOS
911		 * apparently does that.
912		 */
913		if (((entry->ae_flags & ACL_ENTRY_NO_PROPAGATE_INHERIT) ||
914		    !is_directory) &&
915		    entry->ae_entry_type == ACL_ENTRY_TYPE_ALLOW)
916			entry->ae_perm &= ~(ACL_WRITE_ACL | ACL_WRITE_OWNER);
917
918		/*
919		 * 2.A. If the ACL_ENTRY_NO_PROPAGATE_INHERIT is set, or if the object
920		 *      being created is not a directory, then clear the
921		 *      following flags: ACL_ENTRY_NO_PROPAGATE_INHERIT,
922		 *      ACL_ENTRY_FILE_INHERIT, ACL_ENTRY_DIRECTORY_INHERIT,
923		 *      ACL_ENTRY_INHERIT_ONLY.
924		 */
925		if (entry->ae_flags & ACL_ENTRY_NO_PROPAGATE_INHERIT ||
926		    !is_directory) {
927			entry->ae_flags &= ~(ACL_ENTRY_NO_PROPAGATE_INHERIT |
928			ACL_ENTRY_FILE_INHERIT | ACL_ENTRY_DIRECTORY_INHERIT |
929			ACL_ENTRY_INHERIT_ONLY);
930
931			/*
932			 * Continue on to the next ACE.
933			 */
934			continue;
935		}
936
937		/*
938		 * 2.B. If the object is a directory and ACL_ENTRY_FILE_INHERIT
939		 *      is set, but ACL_ENTRY_NO_PROPAGATE_INHERIT is not set, ensure
940		 *      that ACL_ENTRY_INHERIT_ONLY is set.  Continue to the
941		 *      next ACE.  Otherwise...
942		 */
943		/*
944		 * XXX: Read it again and make sure what does the "otherwise"
945		 *      apply to.
946		 */
947		if (is_directory &&
948		    (entry->ae_flags & ACL_ENTRY_FILE_INHERIT) &&
949		    ((entry->ae_flags & ACL_ENTRY_DIRECTORY_INHERIT) == 0)) {
950			entry->ae_flags |= ACL_ENTRY_INHERIT_ONLY;
951			continue;
952		}
953
954		/*
955		 * 2.C. If the type of the ACE is neither ALLOW nor deny,
956		 *      then continue.
957		 */
958		if (entry->ae_entry_type != ACL_ENTRY_TYPE_ALLOW &&
959		    entry->ae_entry_type != ACL_ENTRY_TYPE_DENY)
960			continue;
961
962		/*
963		 * 2.D. Copy the original ACE into a second, adjacent ACE.
964		 */
965		copy = _acl_duplicate_entry(child_aclp, i);
966
967		/*
968		 * 2.E. On the first ACE, ensure that ACL_ENTRY_INHERIT_ONLY
969		 *      is set.
970		 */
971		entry->ae_flags |= ACL_ENTRY_INHERIT_ONLY;
972
973		/*
974		 * 2.F. On the second ACE, clear the following flags:
975		 *      ACL_ENTRY_NO_PROPAGATE_INHERIT, ACL_ENTRY_FILE_INHERIT,
976		 *      ACL_ENTRY_DIRECTORY_INHERIT, ACL_ENTRY_INHERIT_ONLY.
977		 */
978		copy->ae_flags &= ~(ACL_ENTRY_NO_PROPAGATE_INHERIT |
979		    ACL_ENTRY_FILE_INHERIT | ACL_ENTRY_DIRECTORY_INHERIT |
980		    ACL_ENTRY_INHERIT_ONLY);
981
982		/*
983		 * 2.G. On the second ACE, if the type is ALLOW,
984		 *      an implementation MAY clear the following
985		 *      mask bits: ACL_WRITE_ACL, ACL_WRITE_OWNER.
986		 */
987		if (copy->ae_entry_type == ACL_ENTRY_TYPE_ALLOW)
988			copy->ae_perm &= ~(ACL_WRITE_ACL | ACL_WRITE_OWNER);
989
990		/*
991		 * Increment the counter to skip the copied entry.
992		 */
993		i++;
994	}
995
996	/*
997	 * 3. To ensure that the mode is honored, apply the algorithm describe
998	 *    in Section 2.16.6.3, using the mode that is to be used for file
999	 *    creation.
1000	 */
1001	acl_nfs4_sync_acl_from_mode(child_aclp, mode, file_owner_id);
1002}
1003#endif /* _KERNEL */
1004
1005/*
1006 * Populate the ACL with entries inherited from parent_aclp.
1007 */
1008static void
1009acl_nfs4_inherit_entries(const struct acl *parent_aclp,
1010    struct acl *child_aclp, mode_t mode, int file_owner_id,
1011    int is_directory)
1012{
1013	int i, flags, tag;
1014	const struct acl_entry *parent_entry;
1015	struct acl_entry *entry;
1016
1017	KASSERT(parent_aclp->acl_cnt <= ACL_MAX_ENTRIES,
1018	    ("parent_aclp->acl_cnt <= ACL_MAX_ENTRIES"));
1019
1020	for (i = 0; i < parent_aclp->acl_cnt; i++) {
1021		parent_entry = &(parent_aclp->acl_entry[i]);
1022		flags = parent_entry->ae_flags;
1023		tag = parent_entry->ae_tag;
1024
1025		/*
1026		 * Don't inherit owner@, group@, or everyone@ entries.
1027		 */
1028		if (tag == ACL_USER_OBJ || tag == ACL_GROUP_OBJ ||
1029		    tag == ACL_EVERYONE)
1030			continue;
1031
1032		/*
1033		 * Entry is not inheritable at all.
1034		 */
1035		if ((flags & (ACL_ENTRY_DIRECTORY_INHERIT |
1036		    ACL_ENTRY_FILE_INHERIT)) == 0)
1037			continue;
1038
1039		/*
1040		 * We're creating a file, but entry is not inheritable
1041		 * by files.
1042		 */
1043		if (!is_directory && (flags & ACL_ENTRY_FILE_INHERIT) == 0)
1044			continue;
1045
1046		/*
1047		 * Entry is inheritable only by files, but has NO_PROPAGATE
1048		 * flag set, and we're creating a directory, so it wouldn't
1049		 * propagate to any file in that directory anyway.
1050		 */
1051		if (is_directory &&
1052		    (flags & ACL_ENTRY_DIRECTORY_INHERIT) == 0 &&
1053		    (flags & ACL_ENTRY_NO_PROPAGATE_INHERIT))
1054			continue;
1055
1056		/*
1057		 * Entry qualifies for being inherited.
1058		 */
1059		KASSERT(child_aclp->acl_cnt + 1 <= ACL_MAX_ENTRIES,
1060		    ("child_aclp->acl_cnt + 1 <= ACL_MAX_ENTRIES"));
1061		entry = &(child_aclp->acl_entry[child_aclp->acl_cnt]);
1062		*entry = *parent_entry;
1063		child_aclp->acl_cnt++;
1064
1065		entry->ae_flags &= ~ACL_ENTRY_INHERIT_ONLY;
1066		entry->ae_flags |= ACL_ENTRY_INHERITED;
1067
1068		/*
1069		 * If the type of the ACE is neither ALLOW nor DENY,
1070		 * then leave it as it is and proceed to the next one.
1071		 */
1072		if (entry->ae_entry_type != ACL_ENTRY_TYPE_ALLOW &&
1073		    entry->ae_entry_type != ACL_ENTRY_TYPE_DENY)
1074			continue;
1075
1076		/*
1077		 * If the ACL_ENTRY_NO_PROPAGATE_INHERIT is set, or if
1078		 * the object being created is not a directory, then clear
1079		 * the following flags: ACL_ENTRY_NO_PROPAGATE_INHERIT,
1080		 * ACL_ENTRY_FILE_INHERIT, ACL_ENTRY_DIRECTORY_INHERIT,
1081		 * ACL_ENTRY_INHERIT_ONLY.
1082		 */
1083		if (entry->ae_flags & ACL_ENTRY_NO_PROPAGATE_INHERIT ||
1084		    !is_directory) {
1085			entry->ae_flags &= ~(ACL_ENTRY_NO_PROPAGATE_INHERIT |
1086			ACL_ENTRY_FILE_INHERIT | ACL_ENTRY_DIRECTORY_INHERIT |
1087			ACL_ENTRY_INHERIT_ONLY);
1088		}
1089
1090		/*
1091		 * If the object is a directory and ACL_ENTRY_FILE_INHERIT
1092		 * is set, but ACL_ENTRY_DIRECTORY_INHERIT is not set, ensure
1093		 * that ACL_ENTRY_INHERIT_ONLY is set.
1094		 */
1095		if (is_directory &&
1096		    (entry->ae_flags & ACL_ENTRY_FILE_INHERIT) &&
1097		    ((entry->ae_flags & ACL_ENTRY_DIRECTORY_INHERIT) == 0)) {
1098			entry->ae_flags |= ACL_ENTRY_INHERIT_ONLY;
1099		}
1100
1101		if (entry->ae_entry_type == ACL_ENTRY_TYPE_ALLOW &&
1102		    (entry->ae_flags & ACL_ENTRY_INHERIT_ONLY) == 0) {
1103			/*
1104			 * Some permissions must never be inherited.
1105			 */
1106			entry->ae_perm &= ~(ACL_WRITE_ACL | ACL_WRITE_OWNER |
1107			    ACL_WRITE_NAMED_ATTRS | ACL_WRITE_ATTRIBUTES);
1108
1109			/*
1110			 * Others must be masked according to the file mode.
1111			 */
1112			if ((mode & S_IRGRP) == 0)
1113				entry->ae_perm &= ~ACL_READ_DATA;
1114			if ((mode & S_IWGRP) == 0)
1115				entry->ae_perm &=
1116				    ~(ACL_WRITE_DATA | ACL_APPEND_DATA);
1117			if ((mode & S_IXGRP) == 0)
1118				entry->ae_perm &= ~ACL_EXECUTE;
1119		}
1120	}
1121}
1122
1123/*
1124 * Calculate inherited ACL in a manner compatible with PSARC/2010/029.
1125 * It's also being used to calculate a trivial ACL, by inheriting from
1126 * a NULL ACL.
1127 */
1128static void
1129acl_nfs4_compute_inherited_acl_psarc(const struct acl *parent_aclp,
1130    struct acl *aclp, mode_t mode, int file_owner_id, int is_directory)
1131{
1132	acl_perm_t user_allow_first = 0, user_deny = 0, group_deny = 0;
1133	acl_perm_t user_allow, group_allow, everyone_allow;
1134
1135	KASSERT(aclp->acl_cnt == 0, ("aclp->acl_cnt == 0"));
1136
1137	user_allow = group_allow = everyone_allow = ACL_READ_ACL |
1138	    ACL_READ_ATTRIBUTES | ACL_READ_NAMED_ATTRS | ACL_SYNCHRONIZE;
1139	user_allow |= ACL_WRITE_ACL | ACL_WRITE_OWNER | ACL_WRITE_ATTRIBUTES |
1140	    ACL_WRITE_NAMED_ATTRS;
1141
1142	if (mode & S_IRUSR)
1143		user_allow |= ACL_READ_DATA;
1144	if (mode & S_IWUSR)
1145		user_allow |= (ACL_WRITE_DATA | ACL_APPEND_DATA);
1146	if (mode & S_IXUSR)
1147		user_allow |= ACL_EXECUTE;
1148
1149	if (mode & S_IRGRP)
1150		group_allow |= ACL_READ_DATA;
1151	if (mode & S_IWGRP)
1152		group_allow |= (ACL_WRITE_DATA | ACL_APPEND_DATA);
1153	if (mode & S_IXGRP)
1154		group_allow |= ACL_EXECUTE;
1155
1156	if (mode & S_IROTH)
1157		everyone_allow |= ACL_READ_DATA;
1158	if (mode & S_IWOTH)
1159		everyone_allow |= (ACL_WRITE_DATA | ACL_APPEND_DATA);
1160	if (mode & S_IXOTH)
1161		everyone_allow |= ACL_EXECUTE;
1162
1163	user_deny = ((group_allow | everyone_allow) & ~user_allow);
1164	group_deny = everyone_allow & ~group_allow;
1165	user_allow_first = group_deny & ~user_deny;
1166
1167	if (user_allow_first != 0)
1168		_acl_append(aclp, ACL_USER_OBJ, user_allow_first,
1169		    ACL_ENTRY_TYPE_ALLOW);
1170	if (user_deny != 0)
1171		_acl_append(aclp, ACL_USER_OBJ, user_deny,
1172		    ACL_ENTRY_TYPE_DENY);
1173	if (group_deny != 0)
1174		_acl_append(aclp, ACL_GROUP_OBJ, group_deny,
1175		    ACL_ENTRY_TYPE_DENY);
1176
1177	if (parent_aclp != NULL)
1178		acl_nfs4_inherit_entries(parent_aclp, aclp, mode,
1179		    file_owner_id, is_directory);
1180
1181	_acl_append(aclp, ACL_USER_OBJ, user_allow, ACL_ENTRY_TYPE_ALLOW);
1182	_acl_append(aclp, ACL_GROUP_OBJ, group_allow, ACL_ENTRY_TYPE_ALLOW);
1183	_acl_append(aclp, ACL_EVERYONE, everyone_allow, ACL_ENTRY_TYPE_ALLOW);
1184}
1185
1186#ifdef _KERNEL
1187void
1188acl_nfs4_compute_inherited_acl(const struct acl *parent_aclp,
1189    struct acl *child_aclp, mode_t mode, int file_owner_id,
1190    int is_directory)
1191{
1192
1193	if (acl_nfs4_old_semantics)
1194		acl_nfs4_compute_inherited_acl_draft(parent_aclp, child_aclp,
1195		    mode, file_owner_id, is_directory);
1196	else
1197		acl_nfs4_compute_inherited_acl_psarc(parent_aclp, child_aclp,
1198		    mode, file_owner_id, is_directory);
1199}
1200#endif /* _KERNEL */
1201
1202/*
1203 * Calculate trivial ACL in a manner compatible with PSARC/2010/029.
1204 * Note that this results in an ACL different from (but semantically
1205 * equal to) the "canonical six" trivial ACL computed using algorithm
1206 * described in draft-ietf-nfsv4-minorversion1-03.txt, 3.16.6.2.
1207 */
1208static void
1209acl_nfs4_trivial_from_mode(struct acl *aclp, mode_t mode)
1210{
1211
1212	aclp->acl_cnt = 0;
1213	acl_nfs4_compute_inherited_acl_psarc(NULL, aclp, mode, -1, -1);
1214}
1215
1216#ifndef _KERNEL
1217/*
1218 * This routine is used by libc to implement acl_strip_np(3)
1219 * and acl_is_trivial_np(3).
1220 */
1221void
1222acl_nfs4_trivial_from_mode_libc(struct acl *aclp, int mode, int canonical_six)
1223{
1224
1225	aclp->acl_cnt = 0;
1226	if (canonical_six)
1227		acl_nfs4_sync_acl_from_mode_draft(aclp, mode, -1);
1228	else
1229		acl_nfs4_trivial_from_mode(aclp, mode);
1230}
1231#endif /* !_KERNEL */
1232
1233#ifdef _KERNEL
1234static int
1235_acls_are_equal(const struct acl *a, const struct acl *b)
1236{
1237	int i;
1238	const struct acl_entry *entrya, *entryb;
1239
1240	if (a->acl_cnt != b->acl_cnt)
1241		return (0);
1242
1243	for (i = 0; i < b->acl_cnt; i++) {
1244		entrya = &(a->acl_entry[i]);
1245		entryb = &(b->acl_entry[i]);
1246
1247		if (entrya->ae_tag != entryb->ae_tag ||
1248		    entrya->ae_id != entryb->ae_id ||
1249		    entrya->ae_perm != entryb->ae_perm ||
1250		    entrya->ae_entry_type != entryb->ae_entry_type ||
1251		    entrya->ae_flags != entryb->ae_flags)
1252			return (0);
1253	}
1254
1255	return (1);
1256}
1257
1258/*
1259 * This routine is used to determine whether to remove extended attribute
1260 * that stores ACL contents.
1261 */
1262int
1263acl_nfs4_is_trivial(const struct acl *aclp, int file_owner_id)
1264{
1265	int trivial;
1266	mode_t tmpmode = 0;
1267	struct acl *tmpaclp;
1268
1269	if (aclp->acl_cnt > 6)
1270		return (0);
1271
1272	/*
1273	 * Compute the mode from the ACL, then compute new ACL from that mode.
1274	 * If the ACLs are identical, then the ACL is trivial.
1275	 *
1276	 * XXX: I guess there is a faster way to do this.  However, even
1277	 *      this slow implementation significantly speeds things up
1278	 *      for files that don't have non-trivial ACLs - it's critical
1279	 *      for performance to not use EA when they are not needed.
1280	 *
1281	 * First try the PSARC/2010/029 semantics.
1282	 */
1283	tmpaclp = acl_alloc(M_WAITOK | M_ZERO);
1284	acl_nfs4_sync_mode_from_acl(&tmpmode, aclp);
1285	acl_nfs4_trivial_from_mode(tmpaclp, tmpmode);
1286	trivial = _acls_are_equal(aclp, tmpaclp);
1287	if (trivial) {
1288		acl_free(tmpaclp);
1289		return (trivial);
1290	}
1291
1292	/*
1293	 * Check if it's a draft-ietf-nfsv4-minorversion1-03.txt trivial ACL.
1294	 */
1295	tmpaclp->acl_cnt = 0;
1296	acl_nfs4_sync_acl_from_mode_draft(tmpaclp, tmpmode, file_owner_id);
1297	trivial = _acls_are_equal(aclp, tmpaclp);
1298	acl_free(tmpaclp);
1299
1300	return (trivial);
1301}
1302#endif /* _KERNEL */
1303
1304int
1305acl_nfs4_check(const struct acl *aclp, int is_directory)
1306{
1307	int i;
1308	const struct acl_entry *entry;
1309
1310	/*
1311	 * The spec doesn't seem to say anything about ACL validity.
1312	 * It seems there is not much to do here.  There is even no need
1313	 * to count "owner@" or "everyone@" (ACL_USER_OBJ and ACL_EVERYONE)
1314	 * entries, as there can be several of them and that's perfectly
1315	 * valid.  There can be none of them too.  Really.
1316	 */
1317
1318	if (aclp->acl_cnt > ACL_MAX_ENTRIES || aclp->acl_cnt <= 0)
1319		return (EINVAL);
1320
1321	for (i = 0; i < aclp->acl_cnt; i++) {
1322		entry = &(aclp->acl_entry[i]);
1323
1324		switch (entry->ae_tag) {
1325		case ACL_USER_OBJ:
1326		case ACL_GROUP_OBJ:
1327		case ACL_EVERYONE:
1328			if (entry->ae_id != ACL_UNDEFINED_ID)
1329				return (EINVAL);
1330			break;
1331
1332		case ACL_USER:
1333		case ACL_GROUP:
1334			if (entry->ae_id == ACL_UNDEFINED_ID)
1335				return (EINVAL);
1336			break;
1337
1338		default:
1339			return (EINVAL);
1340		}
1341
1342		if ((entry->ae_perm | ACL_NFS4_PERM_BITS) != ACL_NFS4_PERM_BITS)
1343			return (EINVAL);
1344
1345		/*
1346		 * Disallow ACL_ENTRY_TYPE_AUDIT and ACL_ENTRY_TYPE_ALARM for now.
1347		 */
1348		if (entry->ae_entry_type != ACL_ENTRY_TYPE_ALLOW &&
1349		    entry->ae_entry_type != ACL_ENTRY_TYPE_DENY)
1350			return (EINVAL);
1351
1352		if ((entry->ae_flags | ACL_FLAGS_BITS) != ACL_FLAGS_BITS)
1353			return (EINVAL);
1354
1355		/* Disallow unimplemented flags. */
1356		if (entry->ae_flags & (ACL_ENTRY_SUCCESSFUL_ACCESS |
1357		    ACL_ENTRY_FAILED_ACCESS))
1358			return (EINVAL);
1359
1360		/* Disallow flags not allowed for ordinary files. */
1361		if (!is_directory) {
1362			if (entry->ae_flags & (ACL_ENTRY_FILE_INHERIT |
1363			    ACL_ENTRY_DIRECTORY_INHERIT |
1364			    ACL_ENTRY_NO_PROPAGATE_INHERIT | ACL_ENTRY_INHERIT_ONLY))
1365				return (EINVAL);
1366		}
1367	}
1368
1369	return (0);
1370}
1371
1372#ifdef	_KERNEL
1373static int
1374acl_nfs4_modload(module_t module, int what, void *arg)
1375{
1376	int ret;
1377
1378	ret = 0;
1379
1380	switch (what) {
1381	case MOD_LOAD:
1382	case MOD_SHUTDOWN:
1383		break;
1384
1385	case MOD_QUIESCE:
1386		/* XXX TODO */
1387		ret = 0;
1388		break;
1389
1390	case MOD_UNLOAD:
1391		/* XXX TODO */
1392		ret = 0;
1393		break;
1394	default:
1395		ret = EINVAL;
1396		break;
1397	}
1398
1399	return (ret);
1400}
1401
1402static moduledata_t acl_nfs4_mod = {
1403	"acl_nfs4",
1404	acl_nfs4_modload,
1405	NULL
1406};
1407
1408/*
1409 * XXX TODO: which subsystem, order?
1410 */
1411DECLARE_MODULE(acl_nfs4, acl_nfs4_mod, SI_SUB_VFS, SI_ORDER_FIRST);
1412MODULE_VERSION(acl_nfs4, 1);
1413#endif	/* _KERNEL */
1414