1 /*
2 * CDDL HEADER START
3 *
4 * The contents of this file are subject to the terms of the
5 * Common Development and Distribution License (the "License").
6 * You may not use this file except in compliance with the License.
7 *
8 * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
9 * or http://www.opensolaris.org/os/licensing.
10 * See the License for the specific language governing permissions
11 * and limitations under the License.
12 *
13 * When distributing Covered Code, include this CDDL HEADER in each
14 * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
15 * If applicable, add the following below this CDDL HEADER, with the
16 * fields enclosed by brackets "[]" replaced with your own identifying
17 * information: Portions Copyright [yyyy] [name of copyright owner]
18 *
19 * CDDL HEADER END
20 */
21 /*
22 * Copyright 2008 Sun Microsystems, Inc. All rights reserved.
23 * Use is subject to license terms.
24 */
25
26 #include <sys/types.h>
27 #include <sys/stat.h>
28 #include <sys/errno.h>
29 #include <sys/kmem.h>
30 #include <sys/t_lock.h>
31 #include <sys/ksynch.h>
32 #include <sys/buf.h>
33 #include <sys/vfs.h>
34 #include <sys/vnode.h>
35 #include <sys/mode.h>
36 #include <sys/systm.h>
37 #include <vm/seg.h>
38 #include <sys/file.h>
39 #include <sys/acl.h>
40 #include <sys/fs/ufs_inode.h>
41 #include <sys/fs/ufs_acl.h>
42 #include <sys/fs/ufs_quota.h>
43 #include <sys/sysmacros.h>
44 #include <sys/debug.h>
45 #include <sys/policy.h>
46
47 /* Cache routines */
48 static int si_signature(si_t *);
49 static int si_cachei_get(struct inode *, si_t **);
50 static int si_cachea_get(struct inode *, si_t *, si_t **);
51 static int si_cmp(si_t *, si_t *);
52 static void si_cache_put(si_t *);
53 void si_cache_del(si_t *, int);
54 void si_cache_init(void);
55
56 static void ufs_si_free_mem(si_t *);
57 static int ufs_si_store(struct inode *, si_t *, int, cred_t *);
58 static si_t *ufs_acl_cp(si_t *);
59 static int ufs_sectobuf(si_t *, caddr_t *, size_t *);
60 static int acl_count(ufs_ic_acl_t *);
61 static int acl_validate(aclent_t *, int, int);
62 static int vsecattr2aclentry(vsecattr_t *, si_t **);
63 static int aclentry2vsecattr(si_t *, vsecattr_t *);
64
65 krwlock_t si_cache_lock; /* Protects si_cache */
66 int si_cachecnt = 64; /* # buckets in si_cache[a|i] */
67 si_t **si_cachea; /* The 'by acl' cache chains */
68 si_t **si_cachei; /* The 'by inode' cache chains */
69 long si_cachehit = 0;
70 long si_cachemiss = 0;
71
72 #define SI_HASH(S) ((int)(S) & (si_cachecnt - 1))
73
74 /*
75 * Store the new acls in aclp. Attempts to make things atomic.
76 * Search the acl cache for an identical sp and, if found, attach
77 * the cache'd acl to ip. If the acl is new (not in the cache),
78 * add it to the cache, then attach it to ip. Last, remove and
79 * decrement the reference count of any prior acl list attached
80 * to the ip.
81 *
82 * Parameters:
83 * ip - Ptr to inode to receive the acl list
84 * sp - Ptr to in-core acl structure to attach to the inode.
85 * puship - 0 do not push the object inode(ip) 1 push the ip
86 * cr - Ptr to credentials
87 *
88 * Returns: 0 - Success
89 * N - From errno.h
90 */
91 static int
ufs_si_store(struct inode * ip,si_t * sp,int puship,cred_t * cr)92 ufs_si_store(struct inode *ip, si_t *sp, int puship, cred_t *cr)
93 {
94 struct vfs *vfsp;
95 struct inode *sip;
96 si_t *oldsp;
97 si_t *csp;
98 caddr_t acldata;
99 ino_t oldshadow;
100 size_t acldatalen;
101 off_t offset;
102 int shadow;
103 int err;
104 int refcnt;
105 int usecnt;
106 int signature;
107 int resid;
108 struct ufsvfs *ufsvfsp = ip->i_ufsvfs;
109 struct fs *fs = ufsvfsp->vfs_fs;
110
111 ASSERT(RW_WRITE_HELD(&ip->i_contents));
112 ASSERT(ip->i_ufs_acl != sp);
113
114 if (!CHECK_ACL_ALLOWED(ip->i_mode & IFMT))
115 return (ENOSYS);
116
117 /*
118 * if there are only the three owner/group/other then do not
119 * create a shadow inode. If there is already a shadow with
120 * the file, remove it.
121 *
122 */
123 if (!sp->ausers &&
124 !sp->agroups &&
125 !sp->downer &&
126 !sp->dgroup &&
127 !sp->dother &&
128 sp->dclass.acl_ismask == 0 &&
129 !sp->dusers &&
130 !sp->dgroups) {
131 if (ip->i_ufs_acl)
132 err = ufs_si_free(ip->i_ufs_acl, ITOV(ip)->v_vfsp, cr);
133 ip->i_ufs_acl = NULL;
134 ip->i_shadow = 0;
135 ip->i_flag |= IMOD | IACC;
136 ip->i_mode = (ip->i_smode & ~0777) |
137 ((sp->aowner->acl_ic_perm & 07) << 6) |
138 (MASK2MODE(sp)) |
139 (sp->aother->acl_ic_perm & 07);
140 TRANS_INODE(ip->i_ufsvfs, ip);
141 ufs_iupdat(ip, 1);
142 ufs_si_free_mem(sp);
143 return (0);
144 }
145
146 loop:
147
148 /*
149 * Check cache. If in cache, use existing shadow inode.
150 * Increment the shadow link count, then attach to the
151 * cached ufs_acl_entry struct, and increment it's reference
152 * count. Then discard the passed-in ufs_acl_entry and
153 * return.
154 */
155 if (si_cachea_get(ip, sp, &csp) == 0) {
156 ASSERT(RW_WRITE_HELD(&csp->s_lock));
157 if (ip->i_ufs_acl == csp) {
158 rw_exit(&csp->s_lock);
159 (void) ufs_si_free_mem(sp);
160 return (0);
161 }
162 vfsp = ITOV(ip)->v_vfsp;
163 ASSERT(csp->s_shadow <= INT_MAX);
164 shadow = (int)csp->s_shadow;
165 /*
166 * We can't call ufs_iget while holding the csp locked,
167 * because we might deadlock. So we drop the
168 * lock on csp, then go search the si_cache again
169 * to see if the csp is still there.
170 */
171 rw_exit(&csp->s_lock);
172 if ((err = ufs_iget(vfsp, shadow, &sip, cr)) != 0) {
173 (void) ufs_si_free_mem(sp);
174 return (EIO);
175 }
176 rw_enter(&sip->i_contents, RW_WRITER);
177 if ((sip->i_mode & IFMT) != IFSHAD || sip->i_nlink <= 0) {
178 rw_exit(&sip->i_contents);
179 VN_RELE(ITOV(sip));
180 goto loop;
181 }
182 /* Get the csp again */
183 if (si_cachea_get(ip, sp, &csp) != 0) {
184 rw_exit(&sip->i_contents);
185 VN_RELE(ITOV(sip));
186 goto loop;
187 }
188 ASSERT(RW_WRITE_HELD(&csp->s_lock));
189 /* See if we got the right shadow */
190 if (csp->s_shadow != shadow) {
191 rw_exit(&csp->s_lock);
192 rw_exit(&sip->i_contents);
193 VN_RELE(ITOV(sip));
194 goto loop;
195 }
196 ASSERT(RW_WRITE_HELD(&sip->i_contents));
197 ASSERT(sip->i_dquot == 0);
198 /* Increment link count */
199 ASSERT(sip->i_nlink > 0);
200 sip->i_nlink++;
201 TRANS_INODE(ufsvfsp, sip);
202 csp->s_use = sip->i_nlink;
203 csp->s_ref++;
204 ASSERT(sp->s_ref >= 0 && sp->s_ref <= sp->s_use);
205 sip->i_flag |= ICHG | IMOD;
206 sip->i_seq++;
207 ITIMES_NOLOCK(sip);
208 /*
209 * Always release s_lock before both releasing i_contents
210 * and calling VN_RELE.
211 */
212 rw_exit(&csp->s_lock);
213 rw_exit(&sip->i_contents);
214 VN_RELE(ITOV(sip));
215 (void) ufs_si_free_mem(sp);
216 sp = csp;
217 si_cachehit++;
218 goto switchshadows;
219 }
220
221 /* Alloc a shadow inode and fill it in */
222 err = ufs_ialloc(ip, ip->i_number, (mode_t)IFSHAD, &sip, cr);
223 if (err) {
224 (void) ufs_si_free_mem(sp);
225 return (err);
226 }
227 rw_enter(&sip->i_contents, RW_WRITER);
228 sip->i_flag |= IACC | IUPD | ICHG;
229 sip->i_seq++;
230 sip->i_mode = (o_mode_t)IFSHAD;
231 ITOV(sip)->v_type = VREG;
232 ufs_reset_vnode(ITOV(sip));
233 sip->i_nlink = 1;
234 sip->i_uid = crgetuid(cr);
235 sip->i_suid = (ulong_t)sip->i_uid > (ulong_t)USHRT_MAX ?
236 UID_LONG : sip->i_uid;
237 sip->i_gid = crgetgid(cr);
238 sip->i_sgid = (ulong_t)sip->i_gid > (ulong_t)USHRT_MAX ?
239 GID_LONG : sip->i_gid;
240 sip->i_shadow = 0;
241 TRANS_INODE(ufsvfsp, sip);
242 sip->i_ufs_acl = NULL;
243 ASSERT(sip->i_size == 0);
244
245 sp->s_shadow = sip->i_number;
246
247 if ((err = ufs_sectobuf(sp, &acldata, &acldatalen)) != 0)
248 goto errout;
249 offset = 0;
250
251 /*
252 * We don't actually care about the residual count upon failure,
253 * but giving ufs_rdwri() the pointer means it won't translate
254 * all failures to EIO. Our caller needs to know when ENOSPC
255 * gets hit.
256 */
257 resid = 0;
258 if (((err = ufs_rdwri(UIO_WRITE, FWRITE|FSYNC, sip, acldata,
259 acldatalen, (offset_t)0, UIO_SYSSPACE, &resid, cr)) != 0) ||
260 (resid != 0)) {
261 kmem_free(acldata, acldatalen);
262 if ((resid != 0) && (err == 0))
263 err = ENOSPC;
264 goto errout;
265 }
266
267 offset += acldatalen;
268 if ((acldatalen + fs->fs_bsize) > ufsvfsp->vfs_maxacl)
269 ufsvfsp->vfs_maxacl = acldatalen + fs->fs_bsize;
270
271 kmem_free(acldata, acldatalen);
272 /* Sync & free the shadow inode */
273 ufs_iupdat(sip, 1);
274 rw_exit(&sip->i_contents);
275 VN_RELE(ITOV(sip));
276
277 /* We're committed to using this sp */
278 sp->s_use = 1;
279 sp->s_ref = 1;
280
281 /* Now put the new acl stuff in the cache */
282 /* XXX Might make a duplicate */
283 si_cache_put(sp);
284 si_cachemiss++;
285
286 switchshadows:
287 /* Now switch the parent inode to use the new shadow inode */
288 ASSERT(RW_WRITE_HELD(&ip->i_contents));
289 rw_enter(&sp->s_lock, RW_READER);
290 oldsp = ip->i_ufs_acl;
291 oldshadow = ip->i_shadow;
292 ip->i_ufs_acl = sp;
293 ASSERT(sp->s_shadow <= INT_MAX);
294 ip->i_shadow = (int32_t)sp->s_shadow;
295 ASSERT(oldsp != sp);
296 ASSERT(oldshadow != ip->i_number);
297 ASSERT(ip->i_number != ip->i_shadow);
298 /*
299 * Change the mode bits to follow the acl list
300 *
301 * NOTE: a directory is not required to have a "regular" acl
302 * bug id's 1238908, 1257173, 1263171 and 1263188
303 *
304 * but if a "regular" acl is present, it must contain
305 * an "owner", "group", and "other" acl
306 *
307 * If an ACL mask exists, the effective group rights are
308 * set to the mask. Otherwise, the effective group rights
309 * are set to the object group bits.
310 */
311 if (sp->aowner) { /* Owner */
312 ip->i_mode &= ~0700; /* clear Owner */
313 ip->i_mode |= (sp->aowner->acl_ic_perm & 07) << 6;
314 ip->i_uid = sp->aowner->acl_ic_who;
315 }
316
317 if (sp->agroup) { /* Group */
318 ip->i_mode &= ~0070; /* clear Group */
319 ip->i_mode |= MASK2MODE(sp); /* apply mask */
320 ip->i_gid = sp->agroup->acl_ic_who;
321 }
322
323 if (sp->aother) { /* Other */
324 ip->i_mode &= ~0007; /* clear Other */
325 ip->i_mode |= (sp->aother->acl_ic_perm & 07);
326 }
327
328 if (sp->aclass.acl_ismask)
329 ip->i_mode = (ip->i_mode & ~070) |
330 (((sp->aclass.acl_maskbits & 07) << 3) &
331 ip->i_mode);
332
333 TRANS_INODE(ufsvfsp, ip);
334 rw_exit(&sp->s_lock);
335 ip->i_flag |= ICHG;
336 ip->i_seq++;
337 /*
338 * when creating a file there is no need to push the inode, it
339 * is pushed later
340 */
341 if (puship == 1)
342 ufs_iupdat(ip, 1);
343
344 /*
345 * Decrement link count on the old shadow inode,
346 * and decrement reference count on the old aclp,
347 */
348 if (oldshadow) {
349 /* Get the shadow inode */
350 ASSERT(RW_WRITE_HELD(&ip->i_contents));
351 vfsp = ITOV(ip)->v_vfsp;
352 if ((err = ufs_iget_alloced(vfsp, oldshadow, &sip, cr)) != 0) {
353 return (EIO);
354 }
355 /* Decrement link count */
356 rw_enter(&sip->i_contents, RW_WRITER);
357 if (oldsp)
358 rw_enter(&oldsp->s_lock, RW_WRITER);
359 ASSERT(sip->i_dquot == 0);
360 ASSERT(sip->i_nlink > 0);
361 usecnt = --sip->i_nlink;
362 ufs_setreclaim(sip);
363 TRANS_INODE(ufsvfsp, sip);
364 sip->i_flag |= ICHG | IMOD;
365 sip->i_seq++;
366 ITIMES_NOLOCK(sip);
367 if (oldsp) {
368 oldsp->s_use = usecnt;
369 refcnt = --oldsp->s_ref;
370 signature = oldsp->s_signature;
371 /*
372 * Always release s_lock before both releasing
373 * i_contents and calling VN_RELE.
374 */
375 rw_exit(&oldsp->s_lock);
376 }
377 rw_exit(&sip->i_contents);
378 VN_RELE(ITOV(sip));
379 if (oldsp && (refcnt == 0))
380 si_cache_del(oldsp, signature);
381 }
382 return (0);
383
384 errout:
385 /* Throw the newly alloc'd inode away */
386 sip->i_nlink = 0;
387 ufs_setreclaim(sip);
388 TRANS_INODE(ufsvfsp, sip);
389 ITIMES_NOLOCK(sip);
390 rw_exit(&sip->i_contents);
391 VN_RELE(ITOV(sip));
392 ASSERT(!sp->s_use && !sp->s_ref && !(sp->s_flags & SI_CACHED));
393 (void) ufs_si_free_mem(sp);
394 return (err);
395 }
396
397 /*
398 * Load the acls for inode ip either from disk (adding to the cache),
399 * or search the cache and attach the cache'd acl list to the ip.
400 * In either case, maintain the proper reference count on the cached entry.
401 *
402 * Parameters:
403 * ip - Ptr to the inode which needs the acl list loaded
404 * cr - Ptr to credentials
405 *
406 * Returns: 0 - Success
407 * N - From errno.h
408 */
409 /*
410 * ip parent inode in
411 * cr credentials in
412 */
413 int
ufs_si_load(struct inode * ip,cred_t * cr)414 ufs_si_load(struct inode *ip, cred_t *cr)
415 {
416 struct vfs *vfsp;
417 struct inode *sip;
418 ufs_fsd_t *fsdp;
419 si_t *sp;
420 vsecattr_t vsecattr = { 0, 0, NULL, 0, NULL};
421 aclent_t *aclp;
422 ufs_acl_t *ufsaclp;
423 caddr_t acldata = NULL;
424 ino_t maxino;
425 int err;
426 size_t acldatalen;
427 int numacls;
428 int shadow;
429 int usecnt;
430 struct ufsvfs *ufsvfsp = ip->i_ufsvfs;
431 struct fs *fs = ufsvfsp->vfs_fs;
432
433 ASSERT(ip != NULL);
434 ASSERT(RW_WRITE_HELD(&ip->i_contents));
435 ASSERT(ip->i_shadow && ip->i_ufs_acl == NULL);
436 ASSERT((ip->i_mode & IFMT) != IFSHAD);
437
438 if (!CHECK_ACL_ALLOWED(ip->i_mode & IFMT))
439 return (ENOSYS);
440
441 if (ip->i_shadow == ip->i_number)
442 return (EIO);
443
444 maxino = (ino_t)(ITOF(ip)->fs_ncg * ITOF(ip)->fs_ipg);
445 if (ip->i_shadow < UFSROOTINO || ip->i_shadow > maxino)
446 return (EIO);
447
448 /*
449 * XXX Check cache. If in cache, link to it and increment
450 * the reference count, then return.
451 */
452 if (si_cachei_get(ip, &sp) == 0) {
453 ASSERT(RW_WRITE_HELD(&sp->s_lock));
454 ip->i_ufs_acl = sp;
455 sp->s_ref++;
456 ASSERT(sp->s_ref >= 0 && sp->s_ref <= sp->s_use);
457 rw_exit(&sp->s_lock);
458 si_cachehit++;
459 return (0);
460 }
461
462 /* Get the shadow inode */
463 vfsp = ITOV(ip)->v_vfsp;
464 shadow = ip->i_shadow;
465 if ((err = ufs_iget_alloced(vfsp, shadow, &sip, cr)) != 0) {
466 return (err);
467 }
468 rw_enter(&sip->i_contents, RW_WRITER);
469
470 if ((sip->i_mode & IFMT) != IFSHAD) {
471 rw_exit(&sip->i_contents);
472 err = EINVAL;
473 goto alldone;
474 }
475
476 ASSERT(sip->i_dquot == 0);
477 usecnt = sip->i_nlink;
478 if ((!ULOCKFS_IS_NOIACC(&ufsvfsp->vfs_ulockfs)) &&
479 (!(sip)->i_ufsvfs->vfs_noatime)) {
480 sip->i_flag |= IACC;
481 }
482 rw_downgrade(&sip->i_contents);
483
484 ASSERT(sip->i_size <= MAXOFF_T);
485 /* Read the acl's and other stuff from disk */
486 acldata = kmem_zalloc((size_t)sip->i_size, KM_SLEEP);
487 acldatalen = sip->i_size;
488
489 err = ufs_rdwri(UIO_READ, FREAD, sip, acldata, acldatalen, (offset_t)0,
490 UIO_SYSSPACE, (int *)0, cr);
491
492 rw_exit(&sip->i_contents);
493
494 if (err)
495 goto alldone;
496
497 /*
498 * Convert from disk format
499 * Result is a vsecattr struct which we then convert to the
500 * si struct.
501 */
502 bzero((caddr_t)&vsecattr, sizeof (vsecattr_t));
503 for (fsdp = (ufs_fsd_t *)acldata;
504 fsdp < (ufs_fsd_t *)(acldata + acldatalen);
505 fsdp = (ufs_fsd_t *)((caddr_t)fsdp +
506 FSD_RECSZ(fsdp, fsdp->fsd_size))) {
507 if (fsdp->fsd_size <= 0)
508 break;
509 switch (fsdp->fsd_type) {
510 case FSD_ACL:
511 numacls = vsecattr.vsa_aclcnt =
512 (int)((fsdp->fsd_size -
513 2 * sizeof (int)) / sizeof (ufs_acl_t));
514 aclp = vsecattr.vsa_aclentp =
515 kmem_zalloc(numacls * sizeof (aclent_t), KM_SLEEP);
516 for (ufsaclp = (ufs_acl_t *)fsdp->fsd_data;
517 numacls; ufsaclp++) {
518 aclp->a_type = ufsaclp->acl_tag;
519 aclp->a_id = ufsaclp->acl_who;
520 aclp->a_perm = ufsaclp->acl_perm;
521 aclp++;
522 numacls--;
523 }
524 break;
525 case FSD_DFACL:
526 numacls = vsecattr.vsa_dfaclcnt =
527 (int)((fsdp->fsd_size -
528 2 * sizeof (int)) / sizeof (ufs_acl_t));
529 aclp = vsecattr.vsa_dfaclentp =
530 kmem_zalloc(numacls * sizeof (aclent_t), KM_SLEEP);
531 for (ufsaclp = (ufs_acl_t *)fsdp->fsd_data;
532 numacls; ufsaclp++) {
533 aclp->a_type = ufsaclp->acl_tag;
534 aclp->a_id = ufsaclp->acl_who;
535 aclp->a_perm = ufsaclp->acl_perm;
536 aclp++;
537 numacls--;
538 }
539 break;
540 }
541 }
542 /* Sort the lists */
543 if (vsecattr.vsa_aclentp) {
544 ksort((caddr_t)vsecattr.vsa_aclentp, vsecattr.vsa_aclcnt,
545 sizeof (aclent_t), cmp2acls);
546 if ((err = acl_validate(vsecattr.vsa_aclentp,
547 vsecattr.vsa_aclcnt, ACL_CHECK)) != 0) {
548 goto alldone;
549 }
550 }
551 if (vsecattr.vsa_dfaclentp) {
552 ksort((caddr_t)vsecattr.vsa_dfaclentp, vsecattr.vsa_dfaclcnt,
553 sizeof (aclent_t), cmp2acls);
554 if ((err = acl_validate(vsecattr.vsa_dfaclentp,
555 vsecattr.vsa_dfaclcnt, DEF_ACL_CHECK)) != 0) {
556 goto alldone;
557 }
558 }
559
560 /* ignore shadow inodes without ACLs */
561 if (!vsecattr.vsa_aclentp && !vsecattr.vsa_dfaclentp) {
562 err = 0;
563 goto alldone;
564 }
565
566 /* Convert from vsecattr struct to ufs_acl_entry struct */
567 if ((err = vsecattr2aclentry(&vsecattr, &sp)) != 0) {
568 goto alldone;
569 }
570
571 /* There aren't filled in by vsecattr2aclentry */
572 sp->s_shadow = ip->i_shadow;
573 sp->s_dev = ip->i_dev;
574 sp->s_use = usecnt;
575 sp->s_ref = 1;
576 ASSERT(sp->s_ref >= 0 && sp->s_ref <= sp->s_use);
577
578 /* XXX Might make a duplicate */
579 si_cache_put(sp);
580
581 /* Signal anyone waiting on this shadow to be loaded */
582 ip->i_ufs_acl = sp;
583 err = 0;
584 si_cachemiss++;
585 if ((acldatalen + fs->fs_bsize) > ufsvfsp->vfs_maxacl)
586 ufsvfsp->vfs_maxacl = acldatalen + fs->fs_bsize;
587 alldone:
588 /*
589 * Common exit point. Mark shadow inode as ISTALE
590 * if we detect an internal inconsistency, to
591 * prevent stray inodes appearing in the cache.
592 */
593 if (err) {
594 rw_enter(&sip->i_contents, RW_READER);
595 mutex_enter(&sip->i_tlock);
596 sip->i_flag |= ISTALE;
597 mutex_exit(&sip->i_tlock);
598 rw_exit(&sip->i_contents);
599 }
600 VN_RELE(ITOV(sip));
601
602 /*
603 * Cleanup of data structures allocated
604 * on the fly.
605 */
606 if (acldata)
607 kmem_free(acldata, acldatalen);
608
609 if (vsecattr.vsa_aclentp)
610 kmem_free(vsecattr.vsa_aclentp,
611 vsecattr.vsa_aclcnt * sizeof (aclent_t));
612 if (vsecattr.vsa_dfaclentp)
613 kmem_free(vsecattr.vsa_dfaclentp,
614 vsecattr.vsa_dfaclcnt * sizeof (aclent_t));
615 return (err);
616 }
617
618 /*
619 * Check the inode's ACL's to see if this mode of access is
620 * allowed; return 0 if allowed, EACCES if not.
621 *
622 * We follow the procedure defined in Sec. 3.3.5, ACL Access
623 * Check Algorithm, of the POSIX 1003.6 Draft Standard.
624 */
625 /*
626 * ip parent inode
627 * mode mode of access read, write, execute/examine
628 * cr credentials
629 */
630 int
ufs_acl_access(struct inode * ip,int mode,cred_t * cr)631 ufs_acl_access(struct inode *ip, int mode, cred_t *cr)
632 {
633 ufs_ic_acl_t *acl;
634 int ismask, mask = 0;
635 int gperm = 0;
636 int ngroup = 0;
637 si_t *sp = NULL;
638 uid_t uid = crgetuid(cr);
639 uid_t owner;
640
641 ASSERT(ip->i_ufs_acl != NULL);
642 ASSERT(RW_LOCK_HELD(&ip->i_contents));
643
644 sp = ip->i_ufs_acl;
645
646 ismask = sp->aclass.acl_ismask ?
647 sp->aclass.acl_ismask : 0;
648
649 if (ismask)
650 mask = sp->aclass.acl_maskbits;
651 else
652 mask = -1;
653
654 /*
655 * (1) If user owns the file, obey user mode bits
656 */
657 owner = sp->aowner->acl_ic_who;
658 if (uid == owner) {
659 return (MODE_CHECK(owner, mode, (sp->aowner->acl_ic_perm << 6),
660 cr, ip));
661 }
662
663 /*
664 * (2) Obey any matching ACL_USER entry
665 */
666 if (sp->ausers)
667 for (acl = sp->ausers; acl != NULL; acl = acl->acl_ic_next) {
668 if (acl->acl_ic_who == uid) {
669 return (MODE_CHECK(owner, mode,
670 (mask & acl->acl_ic_perm) << 6, cr, ip));
671 }
672 }
673
674 /*
675 * (3) If user belongs to file's group, obey group mode bits
676 * if no ACL mask is defined; if there is an ACL mask, we look
677 * at both the group mode bits and any ACL_GROUP entries.
678 */
679 if (groupmember((uid_t)sp->agroup->acl_ic_who, cr)) {
680 ngroup++;
681 gperm = (sp->agroup->acl_ic_perm);
682 if (!ismask)
683 return (MODE_CHECK(owner, mode, (gperm << 6), cr, ip));
684 }
685
686 /*
687 * (4) Accumulate the permissions in matching ACL_GROUP entries
688 */
689 if (sp->agroups)
690 for (acl = sp->agroups; acl != NULL; acl = acl->acl_ic_next) {
691 if (groupmember(acl->acl_ic_who, cr)) {
692 ngroup++;
693 gperm |= acl->acl_ic_perm;
694 }
695 }
696
697 if (ngroup != 0)
698 return (MODE_CHECK(owner, mode, ((gperm & mask) << 6), cr, ip));
699
700 /*
701 * (5) Finally, use the "other" mode bits
702 */
703 return (MODE_CHECK(owner, mode, sp->aother->acl_ic_perm << 6, cr, ip));
704 }
705
706 /*ARGSUSED2*/
707 int
ufs_acl_get(struct inode * ip,vsecattr_t * vsap,int flag,cred_t * cr)708 ufs_acl_get(struct inode *ip, vsecattr_t *vsap, int flag, cred_t *cr)
709 {
710 aclent_t *aclentp;
711
712 ASSERT(RW_LOCK_HELD(&ip->i_contents));
713
714 /* XXX Range check, sanity check, shadow check */
715 /* If an ACL is present, get the data from the shadow inode info */
716 if (ip->i_ufs_acl)
717 return (aclentry2vsecattr(ip->i_ufs_acl, vsap));
718
719 /*
720 * If no ACLs are present, fabricate one from the mode bits.
721 * This code is almost identical to fs_fab_acl(), but we
722 * already have the mode bits handy, so we'll avoid going
723 * through VOP_GETATTR() again.
724 */
725
726 vsap->vsa_aclcnt = 0;
727 vsap->vsa_aclentp = NULL;
728 vsap->vsa_dfaclcnt = 0; /* Default ACLs are not fabricated */
729 vsap->vsa_dfaclentp = NULL;
730
731 if (vsap->vsa_mask & (VSA_ACLCNT | VSA_ACL))
732 vsap->vsa_aclcnt = 4; /* USER, GROUP, OTHER, and CLASS */
733
734 if (vsap->vsa_mask & VSA_ACL) {
735 vsap->vsa_aclentp = kmem_zalloc(4 * sizeof (aclent_t),
736 KM_SLEEP);
737 if (vsap->vsa_aclentp == NULL)
738 return (ENOMEM);
739 aclentp = vsap->vsa_aclentp;
740
741 /* Owner */
742 aclentp->a_type = USER_OBJ;
743 aclentp->a_perm = ((ushort_t)(ip->i_mode & 0700)) >> 6;
744 aclentp->a_id = ip->i_uid; /* Really undefined */
745 aclentp++;
746
747 /* Group */
748 aclentp->a_type = GROUP_OBJ;
749 aclentp->a_perm = ((ushort_t)(ip->i_mode & 0070)) >> 3;
750 aclentp->a_id = ip->i_gid; /* Really undefined */
751 aclentp++;
752
753 /* Other */
754 aclentp->a_type = OTHER_OBJ;
755 aclentp->a_perm = ip->i_mode & 0007;
756 aclentp->a_id = 0; /* Really undefined */
757 aclentp++;
758
759 /* Class */
760 aclentp->a_type = CLASS_OBJ;
761 aclentp->a_perm = ((ushort_t)(ip->i_mode & 0070)) >> 3;
762 aclentp->a_id = 0; /* Really undefined */
763 ksort((caddr_t)vsap->vsa_aclentp, vsap->vsa_aclcnt,
764 sizeof (aclent_t), cmp2acls);
765 }
766
767 return (0);
768 }
769
770 /*ARGSUSED2*/
771 int
ufs_acl_set(struct inode * ip,vsecattr_t * vsap,int flag,cred_t * cr)772 ufs_acl_set(struct inode *ip, vsecattr_t *vsap, int flag, cred_t *cr)
773 {
774 si_t *sp;
775 int err;
776
777 ASSERT(RW_WRITE_HELD(&ip->i_contents));
778
779 if (!CHECK_ACL_ALLOWED(ip->i_mode & IFMT))
780 return (ENOSYS);
781
782 /*
783 * only the owner of the file or privileged users can change the ACLs
784 */
785 if (secpolicy_vnode_setdac(cr, ip->i_uid) != 0)
786 return (EPERM);
787
788 /* Convert from vsecattr struct to ufs_acl_entry struct */
789 if ((err = vsecattr2aclentry(vsap, &sp)) != 0)
790 return (err);
791 sp->s_dev = ip->i_dev;
792
793 /*
794 * Make the user & group objs in the acl list follow what's
795 * in the inode.
796 */
797 #ifdef DEBUG
798 if (vsap->vsa_mask == VSA_ACL) {
799 ASSERT(sp->aowner);
800 ASSERT(sp->agroup);
801 ASSERT(sp->aother);
802 }
803 #endif /* DEBUG */
804
805 if (sp->aowner)
806 sp->aowner->acl_ic_who = ip->i_uid;
807 if (sp->agroup)
808 sp->agroup->acl_ic_who = ip->i_gid;
809
810 /*
811 * Write and cache the new acl list
812 */
813 err = ufs_si_store(ip, sp, 1, cr);
814
815 return (err);
816 }
817
818 /*
819 * XXX Scan sorted array of acl's, checking for:
820 * 1) Any duplicate/conflicting entries (same type and id)
821 * 2) More than 1 of USER_OBJ, GROUP_OBJ, OTHER_OBJ, CLASS_OBJ
822 * 3) More than 1 of DEF_USER_OBJ, DEF_GROUP_OBJ, DEF_OTHER_OBJ, DEF_CLASS_OBJ
823 *
824 * Parameters:
825 * aclentp - ptr to sorted list of acl entries.
826 * nentries - # acl entries on the list
827 * flag - Bitmap (ACL_CHECK and/or DEF_ACL_CHECK) indicating whether the
828 * list contains regular acls, default acls, or both.
829 *
830 * Returns: 0 - Success
831 * EINVAL - Invalid list (dups or multiple entries of type USER_OBJ, etc)
832 */
833 static int
acl_validate(aclent_t * aclentp,int nentries,int flag)834 acl_validate(aclent_t *aclentp, int nentries, int flag)
835 {
836 int i;
837 int nuser_objs = 0;
838 int ngroup_objs = 0;
839 int nother_objs = 0;
840 int nclass_objs = 0;
841 int ndef_user_objs = 0;
842 int ndef_group_objs = 0;
843 int ndef_other_objs = 0;
844 int ndef_class_objs = 0;
845 int nusers = 0;
846 int ngroups = 0;
847 int ndef_users = 0;
848 int ndef_groups = 0;
849 int numdefs = 0;
850
851 /* Null list or list of one */
852 if (aclentp == NULL)
853 return (0);
854
855 if (nentries <= 0)
856 return (EINVAL);
857
858 for (i = 1; i < nentries; i++) {
859 if (((aclentp[i - 1].a_type == aclentp[i].a_type) &&
860 (aclentp[i - 1].a_id == aclentp[i].a_id)) ||
861 (aclentp[i - 1].a_perm > 07)) {
862 return (EINVAL);
863 }
864 }
865
866 if (flag == 0 || (flag != ACL_CHECK && flag != DEF_ACL_CHECK))
867 return (EINVAL);
868
869 /* Count types */
870 for (i = 0; i < nentries; i++) {
871 switch (aclentp[i].a_type) {
872 case USER_OBJ: /* Owner */
873 nuser_objs++;
874 break;
875 case GROUP_OBJ: /* Group */
876 ngroup_objs++;
877 break;
878 case OTHER_OBJ: /* Other */
879 nother_objs++;
880 break;
881 case CLASS_OBJ: /* Mask */
882 nclass_objs++;
883 break;
884 case DEF_USER_OBJ: /* Default Owner */
885 ndef_user_objs++;
886 break;
887 case DEF_GROUP_OBJ: /* Default Group */
888 ndef_group_objs++;
889 break;
890 case DEF_OTHER_OBJ: /* Default Other */
891 ndef_other_objs++;
892 break;
893 case DEF_CLASS_OBJ: /* Default Mask */
894 ndef_class_objs++;
895 break;
896 case USER: /* Users */
897 nusers++;
898 break;
899 case GROUP: /* Groups */
900 ngroups++;
901 break;
902 case DEF_USER: /* Default Users */
903 ndef_users++;
904 break;
905 case DEF_GROUP: /* Default Groups */
906 ndef_groups++;
907 break;
908 default: /* Unknown type */
909 return (EINVAL);
910 }
911 }
912
913 /*
914 * For normal acl's, we require there be one (and only one)
915 * USER_OBJ, GROUP_OBJ and OTHER_OBJ. There is either zero
916 * or one CLASS_OBJ.
917 */
918 if (flag & ACL_CHECK) {
919 if (nuser_objs != 1 || ngroup_objs != 1 ||
920 nother_objs != 1 || nclass_objs > 1) {
921 return (EINVAL);
922 }
923 /*
924 * If there are ANY group acls, there MUST be a
925 * class_obj(mask) acl (1003.6/D12 p. 29 lines 75-80).
926 */
927 if (ngroups && !nclass_objs) {
928 return (EINVAL);
929 }
930 if (nuser_objs + ngroup_objs + nother_objs + nclass_objs +
931 ngroups + nusers > MAX_ACL_ENTRIES)
932 return (EINVAL);
933 }
934
935 /*
936 * For default acl's, we require that there be either one (and only one)
937 * DEF_USER_OBJ, DEF_GROUP_OBJ and DEF_OTHER_OBJ
938 * or there be none of them.
939 */
940 if (flag & DEF_ACL_CHECK) {
941 if (ndef_other_objs > 1 || ndef_user_objs > 1 ||
942 ndef_group_objs > 1 || ndef_class_objs > 1) {
943 return (EINVAL);
944 }
945
946 numdefs = ndef_other_objs + ndef_user_objs + ndef_group_objs;
947
948 if (numdefs != 0 && numdefs != 3) {
949 return (EINVAL);
950 }
951 /*
952 * If there are ANY def_group acls, there MUST be a
953 * def_class_obj(mask) acl (1003.6/D12 P. 29 lines 75-80).
954 * XXX(jimh) This is inferred.
955 */
956 if (ndef_groups && !ndef_class_objs) {
957 return (EINVAL);
958 }
959 if ((ndef_users || ndef_groups) &&
960 ((numdefs != 3) && !ndef_class_objs)) {
961 return (EINVAL);
962 }
963 if (ndef_user_objs + ndef_group_objs + ndef_other_objs +
964 ndef_class_objs + ndef_users + ndef_groups >
965 MAX_ACL_ENTRIES)
966 return (EINVAL);
967 }
968 return (0);
969 }
970
971 static int
formacl(ufs_ic_acl_t ** aclpp,aclent_t * aclentp)972 formacl(ufs_ic_acl_t **aclpp, aclent_t *aclentp)
973 {
974 ufs_ic_acl_t *uaclp;
975
976 uaclp = kmem_alloc(sizeof (ufs_ic_acl_t), KM_SLEEP);
977 uaclp->acl_ic_perm = aclentp->a_perm;
978 uaclp->acl_ic_who = aclentp->a_id;
979 uaclp->acl_ic_next = *aclpp;
980 *aclpp = uaclp;
981 return (0);
982 }
983
984 /*
985 * XXX - Make more efficient
986 * Convert from the vsecattr struct, used by the VOP interface, to
987 * the ufs_acl_entry struct used for in-core storage of acl's.
988 *
989 * Parameters:
990 * vsap - Ptr to array of security attributes.
991 * spp - Ptr to ptr to si struct for the results
992 *
993 * Returns: 0 - Success
994 * N - From errno.h
995 */
996 static int
vsecattr2aclentry(vsecattr_t * vsap,si_t ** spp)997 vsecattr2aclentry(vsecattr_t *vsap, si_t **spp)
998 {
999 aclent_t *aclentp, *aclp;
1000 si_t *sp;
1001 int err;
1002 int i;
1003
1004 /* Sort & validate the lists on the vsap */
1005 ksort((caddr_t)vsap->vsa_aclentp, vsap->vsa_aclcnt,
1006 sizeof (aclent_t), cmp2acls);
1007 ksort((caddr_t)vsap->vsa_dfaclentp, vsap->vsa_dfaclcnt,
1008 sizeof (aclent_t), cmp2acls);
1009 if ((err = acl_validate(vsap->vsa_aclentp,
1010 vsap->vsa_aclcnt, ACL_CHECK)) != 0)
1011 return (err);
1012 if ((err = acl_validate(vsap->vsa_dfaclentp,
1013 vsap->vsa_dfaclcnt, DEF_ACL_CHECK)) != 0)
1014 return (err);
1015
1016 /* Create new si struct and hang acl's off it */
1017 sp = kmem_zalloc(sizeof (si_t), KM_SLEEP);
1018 rw_init(&sp->s_lock, NULL, RW_DEFAULT, NULL);
1019
1020 /* Process acl list */
1021 aclp = (aclent_t *)vsap->vsa_aclentp;
1022 aclentp = aclp + vsap->vsa_aclcnt - 1;
1023 for (i = 0; i < vsap->vsa_aclcnt; i++) {
1024 switch (aclentp->a_type) {
1025 case USER_OBJ: /* Owner */
1026 if (err = formacl(&sp->aowner, aclentp))
1027 goto error;
1028 break;
1029 case GROUP_OBJ: /* Group */
1030 if (err = formacl(&sp->agroup, aclentp))
1031 goto error;
1032 break;
1033 case OTHER_OBJ: /* Other */
1034 if (err = formacl(&sp->aother, aclentp))
1035 goto error;
1036 break;
1037 case USER:
1038 if (err = formacl(&sp->ausers, aclentp))
1039 goto error;
1040 break;
1041 case CLASS_OBJ: /* Mask */
1042 sp->aclass.acl_ismask = 1;
1043 sp->aclass.acl_maskbits = aclentp->a_perm;
1044 break;
1045 case GROUP:
1046 if (err = formacl(&sp->agroups, aclentp))
1047 goto error;
1048 break;
1049 default:
1050 break;
1051 }
1052 aclentp--;
1053 }
1054
1055 /* Process default acl list */
1056 aclp = (aclent_t *)vsap->vsa_dfaclentp;
1057 aclentp = aclp + vsap->vsa_dfaclcnt - 1;
1058 for (i = 0; i < vsap->vsa_dfaclcnt; i++) {
1059 switch (aclentp->a_type) {
1060 case DEF_USER_OBJ: /* Default Owner */
1061 if (err = formacl(&sp->downer, aclentp))
1062 goto error;
1063 break;
1064 case DEF_GROUP_OBJ: /* Default Group */
1065 if (err = formacl(&sp->dgroup, aclentp))
1066 goto error;
1067 break;
1068 case DEF_OTHER_OBJ: /* Default Other */
1069 if (err = formacl(&sp->dother, aclentp))
1070 goto error;
1071 break;
1072 case DEF_USER:
1073 if (err = formacl(&sp->dusers, aclentp))
1074 goto error;
1075 break;
1076 case DEF_CLASS_OBJ: /* Default Mask */
1077 sp->dclass.acl_ismask = 1;
1078 sp->dclass.acl_maskbits = aclentp->a_perm;
1079 break;
1080 case DEF_GROUP:
1081 if (err = formacl(&sp->dgroups, aclentp))
1082 goto error;
1083 break;
1084 default:
1085 break;
1086 }
1087 aclentp--;
1088 }
1089 *spp = sp;
1090 return (0);
1091
1092 error:
1093 ufs_si_free_mem(sp);
1094 return (err);
1095 }
1096
1097 void
formvsec(int obj_type,ufs_ic_acl_t * aclp,aclent_t ** aclentpp)1098 formvsec(int obj_type, ufs_ic_acl_t *aclp, aclent_t **aclentpp)
1099 {
1100 for (; aclp; aclp = aclp->acl_ic_next) {
1101 (*aclentpp)->a_type = obj_type;
1102 (*aclentpp)->a_perm = aclp->acl_ic_perm;
1103 (*aclentpp)->a_id = aclp->acl_ic_who;
1104 (*aclentpp)++;
1105 }
1106 }
1107
1108 /*
1109 * XXX - Make more efficient
1110 * Convert from the ufs_acl_entry struct used for in-core storage of acl's
1111 * to the vsecattr struct, used by the VOP interface.
1112 *
1113 * Parameters:
1114 * sp - Ptr to si struct with the acls
1115 * vsap - Ptr to a vsecattr struct which will take the results.
1116 *
1117 * Returns: 0 - Success
1118 * N - From errno table
1119 */
1120 static int
aclentry2vsecattr(si_t * sp,vsecattr_t * vsap)1121 aclentry2vsecattr(si_t *sp, vsecattr_t *vsap)
1122 {
1123 aclent_t *aclentp;
1124 int numacls = 0;
1125 int err;
1126
1127 vsap->vsa_aclentp = vsap->vsa_dfaclentp = NULL;
1128
1129 numacls = acl_count(sp->aowner) +
1130 acl_count(sp->agroup) +
1131 acl_count(sp->aother) +
1132 acl_count(sp->ausers) +
1133 acl_count(sp->agroups);
1134 if (sp->aclass.acl_ismask)
1135 numacls++;
1136
1137 if (vsap->vsa_mask & (VSA_ACLCNT | VSA_ACL))
1138 vsap->vsa_aclcnt = numacls;
1139
1140 if (numacls == 0)
1141 goto do_defaults;
1142
1143 if (vsap->vsa_mask & VSA_ACL) {
1144 vsap->vsa_aclentp = kmem_zalloc(numacls * sizeof (aclent_t),
1145 KM_SLEEP);
1146 aclentp = vsap->vsa_aclentp;
1147
1148 formvsec(USER_OBJ, sp->aowner, &aclentp);
1149 formvsec(USER, sp->ausers, &aclentp);
1150 formvsec(GROUP_OBJ, sp->agroup, &aclentp);
1151 formvsec(GROUP, sp->agroups, &aclentp);
1152 formvsec(OTHER_OBJ, sp->aother, &aclentp);
1153
1154 if (sp->aclass.acl_ismask) {
1155 aclentp->a_type = CLASS_OBJ; /* Mask */
1156 aclentp->a_perm = sp->aclass.acl_maskbits;
1157 aclentp->a_id = 0;
1158 aclentp++;
1159 }
1160
1161 /* Sort the acl list */
1162 ksort((caddr_t)vsap->vsa_aclentp, vsap->vsa_aclcnt,
1163 sizeof (aclent_t), cmp2acls);
1164 /* Check the acl list */
1165 if ((err = acl_validate(vsap->vsa_aclentp,
1166 vsap->vsa_aclcnt, ACL_CHECK)) != 0) {
1167 kmem_free(vsap->vsa_aclentp,
1168 numacls * sizeof (aclent_t));
1169 vsap->vsa_aclentp = NULL;
1170 return (err);
1171 }
1172
1173 }
1174 do_defaults:
1175 /* Process Defaults */
1176
1177 numacls = acl_count(sp->downer) +
1178 acl_count(sp->dgroup) +
1179 acl_count(sp->dother) +
1180 acl_count(sp->dusers) +
1181 acl_count(sp->dgroups);
1182 if (sp->dclass.acl_ismask)
1183 numacls++;
1184
1185 if (vsap->vsa_mask & (VSA_DFACLCNT | VSA_DFACL))
1186 vsap->vsa_dfaclcnt = numacls;
1187
1188 if (numacls == 0)
1189 goto do_others;
1190
1191 if (vsap->vsa_mask & VSA_DFACL) {
1192 vsap->vsa_dfaclentp =
1193 kmem_zalloc(numacls * sizeof (aclent_t), KM_SLEEP);
1194 aclentp = vsap->vsa_dfaclentp;
1195 formvsec(DEF_USER_OBJ, sp->downer, &aclentp);
1196 formvsec(DEF_USER, sp->dusers, &aclentp);
1197 formvsec(DEF_GROUP_OBJ, sp->dgroup, &aclentp);
1198 formvsec(DEF_GROUP, sp->dgroups, &aclentp);
1199 formvsec(DEF_OTHER_OBJ, sp->dother, &aclentp);
1200
1201 if (sp->dclass.acl_ismask) {
1202 aclentp->a_type = DEF_CLASS_OBJ; /* Mask */
1203 aclentp->a_perm = sp->dclass.acl_maskbits;
1204 aclentp->a_id = 0;
1205 aclentp++;
1206 }
1207
1208 /* Sort the default acl list */
1209 ksort((caddr_t)vsap->vsa_dfaclentp, vsap->vsa_dfaclcnt,
1210 sizeof (aclent_t), cmp2acls);
1211 if ((err = acl_validate(vsap->vsa_dfaclentp,
1212 vsap->vsa_dfaclcnt, DEF_ACL_CHECK)) != 0) {
1213 if (vsap->vsa_aclentp != NULL)
1214 kmem_free(vsap->vsa_aclentp,
1215 vsap->vsa_aclcnt * sizeof (aclent_t));
1216 kmem_free(vsap->vsa_dfaclentp,
1217 vsap->vsa_dfaclcnt * sizeof (aclent_t));
1218 vsap->vsa_aclentp = vsap->vsa_dfaclentp = NULL;
1219 return (err);
1220 }
1221 }
1222
1223 do_others:
1224 return (0);
1225 }
1226
1227 static void
acl_free(ufs_ic_acl_t * aclp)1228 acl_free(ufs_ic_acl_t *aclp)
1229 {
1230 while (aclp != NULL) {
1231 ufs_ic_acl_t *nextaclp = aclp->acl_ic_next;
1232 kmem_free(aclp, sizeof (ufs_ic_acl_t));
1233 aclp = nextaclp;
1234 }
1235 }
1236
1237 /*
1238 * ufs_si_free_mem will discard the sp, and the acl hanging off of the
1239 * sp. It is required that the sp not be locked, and not be in the
1240 * cache.
1241 *
1242 * input: pointer to sp to discard.
1243 *
1244 * return - nothing.
1245 *
1246 */
1247 static void
ufs_si_free_mem(si_t * sp)1248 ufs_si_free_mem(si_t *sp)
1249 {
1250 ASSERT(!(sp->s_flags & SI_CACHED));
1251 ASSERT(!RW_LOCK_HELD(&sp->s_lock));
1252 /*
1253 * remove from the cache
1254 * free the acl entries
1255 */
1256 acl_free(sp->aowner);
1257 acl_free(sp->agroup);
1258 acl_free(sp->aother);
1259 acl_free(sp->ausers);
1260 acl_free(sp->agroups);
1261
1262 acl_free(sp->downer);
1263 acl_free(sp->dgroup);
1264 acl_free(sp->dother);
1265 acl_free(sp->dusers);
1266 acl_free(sp->dgroups);
1267
1268 rw_destroy(&sp->s_lock);
1269 kmem_free(sp, sizeof (si_t));
1270 }
1271
1272 void
acl_cpy(ufs_ic_acl_t * saclp,ufs_ic_acl_t * daclp)1273 acl_cpy(ufs_ic_acl_t *saclp, ufs_ic_acl_t *daclp)
1274 {
1275 ufs_ic_acl_t *aclp, *prev_aclp = NULL, *aclp1;
1276
1277 if (saclp == NULL) {
1278 daclp = NULL;
1279 return;
1280 }
1281 prev_aclp = daclp;
1282
1283 for (aclp = saclp; aclp != NULL; aclp = aclp->acl_ic_next) {
1284 aclp1 = kmem_alloc(sizeof (ufs_ic_acl_t), KM_SLEEP);
1285 aclp1->acl_ic_next = NULL;
1286 aclp1->acl_ic_who = aclp->acl_ic_who;
1287 aclp1->acl_ic_perm = aclp->acl_ic_perm;
1288 prev_aclp->acl_ic_next = aclp1;
1289 prev_aclp = (ufs_ic_acl_t *)&aclp1->acl_ic_next;
1290 }
1291 }
1292
1293 /*
1294 * ufs_si_inherit takes a parent acl structure (saclp) and the inode
1295 * of the object that is inheriting an acl and returns the inode
1296 * with the acl linked to it. It also writes the acl to disk if
1297 * it is a unique inode.
1298 *
1299 * ip - pointer to inode of object inheriting the acl (contents lock)
1300 * tdp - parent inode (rw_lock and contents lock)
1301 * mode - creation modes
1302 * cr - credentials pointer
1303 */
1304 int
ufs_si_inherit(struct inode * ip,struct inode * tdp,o_mode_t mode,cred_t * cr)1305 ufs_si_inherit(struct inode *ip, struct inode *tdp, o_mode_t mode, cred_t *cr)
1306 {
1307 si_t *tsp, *sp = tdp->i_ufs_acl;
1308 int error;
1309 o_mode_t old_modes, old_uid, old_gid;
1310 int mask;
1311
1312 ASSERT(RW_WRITE_HELD(&ip->i_contents));
1313 ASSERT(RW_WRITE_HELD(&tdp->i_rwlock));
1314 ASSERT(RW_WRITE_HELD(&tdp->i_contents));
1315
1316 /*
1317 * if links/symbolic links, or other invalid acl objects are copied
1318 * or moved to a directory with a default acl do not allow inheritance
1319 * just return.
1320 */
1321 if (!CHECK_ACL_ALLOWED(ip->i_mode & IFMT))
1322 return (0);
1323
1324 /* lock the parent security information */
1325 rw_enter(&sp->s_lock, RW_READER);
1326
1327 ASSERT(((tdp->i_mode & IFMT) == IFDIR) ||
1328 ((tdp->i_mode & IFMT) == IFATTRDIR));
1329
1330 mask = ((sp->downer != NULL) ? 1 : 0) |
1331 ((sp->dgroup != NULL) ? 2 : 0) |
1332 ((sp->dother != NULL) ? 4 : 0);
1333
1334 if (mask == 0) {
1335 rw_exit(&sp->s_lock);
1336 return (0);
1337 }
1338
1339 if (mask != 7) {
1340 rw_exit(&sp->s_lock);
1341 return (EINVAL);
1342 }
1343
1344 tsp = kmem_zalloc(sizeof (si_t), KM_SLEEP);
1345 rw_init(&tsp->s_lock, NULL, RW_DEFAULT, NULL);
1346
1347 /* copy the default acls */
1348
1349 ASSERT(RW_READ_HELD(&sp->s_lock));
1350 acl_cpy(sp->downer, (ufs_ic_acl_t *)&tsp->aowner);
1351 acl_cpy(sp->dgroup, (ufs_ic_acl_t *)&tsp->agroup);
1352 acl_cpy(sp->dother, (ufs_ic_acl_t *)&tsp->aother);
1353 acl_cpy(sp->dusers, (ufs_ic_acl_t *)&tsp->ausers);
1354 acl_cpy(sp->dgroups, (ufs_ic_acl_t *)&tsp->agroups);
1355 tsp->aclass.acl_ismask = sp->dclass.acl_ismask;
1356 tsp->aclass.acl_maskbits = sp->dclass.acl_maskbits;
1357
1358 /*
1359 * set the owner, group, and other values from the master
1360 * inode.
1361 */
1362
1363 MODE2ACL(tsp->aowner, (mode >> 6), ip->i_uid);
1364 MODE2ACL(tsp->agroup, (mode >> 3), ip->i_gid);
1365 MODE2ACL(tsp->aother, (mode), 0);
1366
1367 if (tsp->aclass.acl_ismask) {
1368 tsp->aclass.acl_maskbits &= mode >> 3;
1369 }
1370
1371
1372 /* copy default acl if necessary */
1373
1374 if (((ip->i_mode & IFMT) == IFDIR) ||
1375 ((ip->i_mode & IFMT) == IFATTRDIR)) {
1376 acl_cpy(sp->downer, (ufs_ic_acl_t *)&tsp->downer);
1377 acl_cpy(sp->dgroup, (ufs_ic_acl_t *)&tsp->dgroup);
1378 acl_cpy(sp->dother, (ufs_ic_acl_t *)&tsp->dother);
1379 acl_cpy(sp->dusers, (ufs_ic_acl_t *)&tsp->dusers);
1380 acl_cpy(sp->dgroups, (ufs_ic_acl_t *)&tsp->dgroups);
1381 tsp->dclass.acl_ismask = sp->dclass.acl_ismask;
1382 tsp->dclass.acl_maskbits = sp->dclass.acl_maskbits;
1383 }
1384 /*
1385 * save the new 9 mode bits in the inode (ip->ic_smode) for
1386 * ufs_getattr. Be sure the mode can be recovered if the store
1387 * fails.
1388 */
1389 old_modes = ip->i_mode;
1390 old_uid = ip->i_uid;
1391 old_gid = ip->i_gid;
1392 /*
1393 * store the acl, and get back a new security anchor if
1394 * it is a duplicate.
1395 */
1396 rw_exit(&sp->s_lock);
1397 rw_enter(&ip->i_rwlock, RW_WRITER);
1398
1399 /*
1400 * Suppress out of inodes messages if instructed in the
1401 * tdp inode.
1402 */
1403 ip->i_flag |= tdp->i_flag & IQUIET;
1404
1405 if ((error = ufs_si_store(ip, tsp, 0, cr)) != 0) {
1406 ip->i_mode = old_modes;
1407 ip->i_uid = old_uid;
1408 ip->i_gid = old_gid;
1409 }
1410 ip->i_flag &= ~IQUIET;
1411 rw_exit(&ip->i_rwlock);
1412 return (error);
1413 }
1414
1415 si_t *
ufs_acl_cp(si_t * sp)1416 ufs_acl_cp(si_t *sp)
1417 {
1418
1419 si_t *dsp;
1420
1421 ASSERT(RW_READ_HELD(&sp->s_lock));
1422 ASSERT(sp->s_ref && sp->s_use);
1423
1424 dsp = kmem_zalloc(sizeof (si_t), KM_SLEEP);
1425 rw_init(&dsp->s_lock, NULL, RW_DEFAULT, NULL);
1426
1427 acl_cpy(sp->aowner, (ufs_ic_acl_t *)&dsp->aowner);
1428 acl_cpy(sp->agroup, (ufs_ic_acl_t *)&dsp->agroup);
1429 acl_cpy(sp->aother, (ufs_ic_acl_t *)&dsp->aother);
1430 acl_cpy(sp->ausers, (ufs_ic_acl_t *)&dsp->ausers);
1431 acl_cpy(sp->agroups, (ufs_ic_acl_t *)&dsp->agroups);
1432
1433 dsp->aclass.acl_ismask = sp->aclass.acl_ismask;
1434 dsp->aclass.acl_maskbits = sp->aclass.acl_maskbits;
1435
1436 acl_cpy(sp->downer, (ufs_ic_acl_t *)&dsp->downer);
1437 acl_cpy(sp->dgroup, (ufs_ic_acl_t *)&dsp->dgroup);
1438 acl_cpy(sp->dother, (ufs_ic_acl_t *)&dsp->dother);
1439 acl_cpy(sp->dusers, (ufs_ic_acl_t *)&dsp->dusers);
1440 acl_cpy(sp->dgroups, (ufs_ic_acl_t *)&dsp->dgroups);
1441
1442 dsp->dclass.acl_ismask = sp->dclass.acl_ismask;
1443 dsp->dclass.acl_maskbits = sp->dclass.acl_maskbits;
1444
1445 return (dsp);
1446
1447 }
1448
1449 int
ufs_acl_setattr(struct inode * ip,struct vattr * vap,cred_t * cr)1450 ufs_acl_setattr(struct inode *ip, struct vattr *vap, cred_t *cr)
1451 {
1452
1453 si_t *sp;
1454 int mask = vap->va_mask;
1455 int error = 0;
1456
1457 ASSERT(RW_WRITE_HELD(&ip->i_contents));
1458
1459 if (!(mask & (AT_MODE|AT_UID|AT_GID)))
1460 return (0);
1461
1462 /*
1463 * if no regular acl's, nothing to do, so let's get out
1464 */
1465 if (!(ip->i_ufs_acl) || !(ip->i_ufs_acl->aowner))
1466 return (0);
1467
1468 rw_enter(&ip->i_ufs_acl->s_lock, RW_READER);
1469 sp = ufs_acl_cp(ip->i_ufs_acl);
1470 ASSERT(sp != ip->i_ufs_acl);
1471
1472 /*
1473 * set the mask to the group permissions if a mask entry
1474 * exists. Otherwise, set the group obj bits to the group
1475 * permissions. Since non-trivial ACLs always have a mask,
1476 * and the mask is the final arbiter of group permissions,
1477 * setting the mask has the effect of changing the effective
1478 * group permissions, even if the group_obj permissions in
1479 * the ACL aren't changed. Posix P1003.1e states that when
1480 * an ACL mask exists, chmod(2) must set the acl mask (NOT the
1481 * group_obj permissions) to the requested group permissions.
1482 */
1483 if (mask & AT_MODE) {
1484 sp->aowner->acl_ic_perm = (o_mode_t)(ip->i_mode & 0700) >> 6;
1485 if (sp->aclass.acl_ismask)
1486 sp->aclass.acl_maskbits =
1487 (o_mode_t)(ip->i_mode & 070) >> 3;
1488 else
1489 sp->agroup->acl_ic_perm =
1490 (o_mode_t)(ip->i_mode & 070) >> 3;
1491 sp->aother->acl_ic_perm = (o_mode_t)(ip->i_mode & 07);
1492 }
1493
1494 if (mask & AT_UID) {
1495 /* Caller has verified our privileges */
1496 sp->aowner->acl_ic_who = ip->i_uid;
1497 }
1498
1499 if (mask & AT_GID) {
1500 sp->agroup->acl_ic_who = ip->i_gid;
1501 }
1502
1503 rw_exit(&ip->i_ufs_acl->s_lock);
1504 error = ufs_si_store(ip, sp, 0, cr);
1505 return (error);
1506 }
1507
1508 static int
acl_count(ufs_ic_acl_t * p)1509 acl_count(ufs_ic_acl_t *p)
1510 {
1511 ufs_ic_acl_t *acl;
1512 int count;
1513
1514 for (count = 0, acl = p; acl; acl = acl->acl_ic_next, count++)
1515 ;
1516 return (count);
1517 }
1518
1519 /*
1520 * Takes as input a security structure and generates a buffer
1521 * with fsd's in a form which be written to the shadow inode.
1522 */
1523 static int
ufs_sectobuf(si_t * sp,caddr_t * buf,size_t * len)1524 ufs_sectobuf(si_t *sp, caddr_t *buf, size_t *len)
1525 {
1526 size_t acl_size;
1527 size_t def_acl_size;
1528 caddr_t buffer;
1529 struct ufs_fsd *fsdp;
1530 ufs_acl_t *bufaclp;
1531
1532 /*
1533 * Calc size of buffer to hold all the acls
1534 */
1535 acl_size = acl_count(sp->aowner) + /* owner */
1536 acl_count(sp->agroup) + /* owner group */
1537 acl_count(sp->aother) + /* owner other */
1538 acl_count(sp->ausers) + /* acl list */
1539 acl_count(sp->agroups); /* group alcs */
1540 if (sp->aclass.acl_ismask)
1541 acl_size++;
1542
1543 /* Convert to bytes */
1544 acl_size *= sizeof (ufs_acl_t);
1545
1546 /* Add fsd header */
1547 if (acl_size)
1548 acl_size += 2 * sizeof (int);
1549
1550 /*
1551 * Calc size of buffer to hold all the default acls
1552 */
1553 def_acl_size =
1554 acl_count(sp->downer) + /* def owner */
1555 acl_count(sp->dgroup) + /* def owner group */
1556 acl_count(sp->dother) + /* def owner other */
1557 acl_count(sp->dusers) + /* def users */
1558 acl_count(sp->dgroups); /* def group acls */
1559 if (sp->dclass.acl_ismask)
1560 def_acl_size++;
1561
1562 /*
1563 * Convert to bytes
1564 */
1565 def_acl_size *= sizeof (ufs_acl_t);
1566
1567 /*
1568 * Add fsd header
1569 */
1570 if (def_acl_size)
1571 def_acl_size += 2 * sizeof (int);
1572
1573 if (acl_size + def_acl_size == 0)
1574 return (0);
1575
1576 buffer = kmem_zalloc((acl_size + def_acl_size), KM_SLEEP);
1577 bufaclp = (ufs_acl_t *)buffer;
1578
1579 if (acl_size == 0)
1580 goto wrtdefs;
1581
1582 /* create fsd and copy acls */
1583 fsdp = (struct ufs_fsd *)bufaclp;
1584 fsdp->fsd_type = FSD_ACL;
1585 bufaclp = (ufs_acl_t *)&fsdp->fsd_data[0];
1586
1587 ACL_MOVE(sp->aowner, USER_OBJ, bufaclp);
1588 ACL_MOVE(sp->agroup, GROUP_OBJ, bufaclp);
1589 ACL_MOVE(sp->aother, OTHER_OBJ, bufaclp);
1590 ACL_MOVE(sp->ausers, USER, bufaclp);
1591 ACL_MOVE(sp->agroups, GROUP, bufaclp);
1592
1593 if (sp->aclass.acl_ismask) {
1594 bufaclp->acl_tag = CLASS_OBJ;
1595 bufaclp->acl_who = (uid_t)sp->aclass.acl_ismask;
1596 bufaclp->acl_perm = (o_mode_t)sp->aclass.acl_maskbits;
1597 bufaclp++;
1598 }
1599 ASSERT(acl_size <= INT_MAX);
1600 fsdp->fsd_size = (int)acl_size;
1601
1602 wrtdefs:
1603 if (def_acl_size == 0)
1604 goto alldone;
1605
1606 /* if defaults exist then create fsd and copy default acls */
1607 fsdp = (struct ufs_fsd *)bufaclp;
1608 fsdp->fsd_type = FSD_DFACL;
1609 bufaclp = (ufs_acl_t *)&fsdp->fsd_data[0];
1610
1611 ACL_MOVE(sp->downer, DEF_USER_OBJ, bufaclp);
1612 ACL_MOVE(sp->dgroup, DEF_GROUP_OBJ, bufaclp);
1613 ACL_MOVE(sp->dother, DEF_OTHER_OBJ, bufaclp);
1614 ACL_MOVE(sp->dusers, DEF_USER, bufaclp);
1615 ACL_MOVE(sp->dgroups, DEF_GROUP, bufaclp);
1616 if (sp->dclass.acl_ismask) {
1617 bufaclp->acl_tag = DEF_CLASS_OBJ;
1618 bufaclp->acl_who = (uid_t)sp->dclass.acl_ismask;
1619 bufaclp->acl_perm = (o_mode_t)sp->dclass.acl_maskbits;
1620 bufaclp++;
1621 }
1622 ASSERT(def_acl_size <= INT_MAX);
1623 fsdp->fsd_size = (int)def_acl_size;
1624
1625 alldone:
1626 *buf = buffer;
1627 *len = acl_size + def_acl_size;
1628
1629 return (0);
1630 }
1631
1632 /*
1633 * free a shadow inode on disk and in memory
1634 */
1635 int
ufs_si_free(si_t * sp,struct vfs * vfsp,cred_t * cr)1636 ufs_si_free(si_t *sp, struct vfs *vfsp, cred_t *cr)
1637 {
1638 struct inode *sip;
1639 int shadow;
1640 int err = 0;
1641 int refcnt;
1642 int signature;
1643
1644 ASSERT(vfsp);
1645 ASSERT(sp);
1646
1647 rw_enter(&sp->s_lock, RW_READER);
1648 ASSERT(sp->s_shadow <= INT_MAX);
1649 shadow = (int)sp->s_shadow;
1650 ASSERT(sp->s_ref);
1651 rw_exit(&sp->s_lock);
1652
1653 /*
1654 * Decrement link count on the shadow inode,
1655 * and decrement reference count on the sip.
1656 */
1657 if ((err = ufs_iget_alloced(vfsp, shadow, &sip, cr)) == 0) {
1658 rw_enter(&sip->i_contents, RW_WRITER);
1659 rw_enter(&sp->s_lock, RW_WRITER);
1660 ASSERT(sp->s_shadow == shadow);
1661 ASSERT(sip->i_dquot == 0);
1662 /* Decrement link count */
1663 ASSERT(sip->i_nlink > 0);
1664 /*
1665 * bug #1264710 assertion failure below
1666 */
1667 sp->s_use = --sip->i_nlink;
1668 ufs_setreclaim(sip);
1669 TRANS_INODE(sip->i_ufsvfs, sip);
1670 sip->i_flag |= ICHG | IMOD;
1671 sip->i_seq++;
1672 ITIMES_NOLOCK(sip);
1673 /* Dec ref counts on si referenced by this ip */
1674 refcnt = --sp->s_ref;
1675 signature = sp->s_signature;
1676 ASSERT(sp->s_ref >= 0 && sp->s_ref <= sp->s_use);
1677 /*
1678 * Release s_lock before calling VN_RELE
1679 * (which may want to acquire i_contents).
1680 */
1681 rw_exit(&sp->s_lock);
1682 rw_exit(&sip->i_contents);
1683 VN_RELE(ITOV(sip));
1684 } else {
1685 rw_enter(&sp->s_lock, RW_WRITER);
1686 /* Dec ref counts on si referenced by this ip */
1687 refcnt = --sp->s_ref;
1688 signature = sp->s_signature;
1689 ASSERT(sp->s_ref >= 0 && sp->s_ref <= sp->s_use);
1690 rw_exit(&sp->s_lock);
1691 }
1692
1693 if (refcnt == 0)
1694 si_cache_del(sp, signature);
1695 return (err);
1696 }
1697
1698 /*
1699 * Seach the si cache for an si structure by inode #.
1700 * Returns a locked si structure.
1701 *
1702 * Parameters:
1703 * ip - Ptr to an inode on this fs
1704 * spp - Ptr to ptr to si struct for the results, if found.
1705 *
1706 * Returns: 0 - Success (results in spp)
1707 * 1 - Failure (spp undefined)
1708 */
1709 static int
si_cachei_get(struct inode * ip,si_t ** spp)1710 si_cachei_get(struct inode *ip, si_t **spp)
1711 {
1712 si_t *sp;
1713
1714 rw_enter(&si_cache_lock, RW_READER);
1715 loop:
1716 for (sp = si_cachei[SI_HASH(ip->i_shadow)]; sp; sp = sp->s_forw)
1717 if (sp->s_shadow == ip->i_shadow && sp->s_dev == ip->i_dev)
1718 break;
1719
1720 if (sp == NULL) {
1721 /* Not in cache */
1722 rw_exit(&si_cache_lock);
1723 return (1);
1724 }
1725 /* Found it */
1726 rw_enter(&sp->s_lock, RW_WRITER);
1727 alldone:
1728 rw_exit(&si_cache_lock);
1729 *spp = sp;
1730 return (0);
1731 }
1732
1733 /*
1734 * Seach the si cache by si structure (ie duplicate of the one passed in).
1735 * In order for a match the signatures must be the same and
1736 * the devices must be the same, the acls must match and
1737 * link count of the cached shadow must be less than the
1738 * size of ic_nlink - 1. MAXLINK - 1 is used to allow the count
1739 * to be incremented one more time by the caller.
1740 * Returns a locked si structure.
1741 *
1742 * Parameters:
1743 * ip - Ptr to an inode on this fs
1744 * spi - Ptr to si the struct we're searching the cache for.
1745 * spp - Ptr to ptr to si struct for the results, if found.
1746 *
1747 * Returns: 0 - Success (results in spp)
1748 * 1 - Failure (spp undefined)
1749 */
1750 static int
si_cachea_get(struct inode * ip,si_t * spi,si_t ** spp)1751 si_cachea_get(struct inode *ip, si_t *spi, si_t **spp)
1752 {
1753 si_t *sp;
1754
1755 spi->s_dev = ip->i_dev;
1756 spi->s_signature = si_signature(spi);
1757 rw_enter(&si_cache_lock, RW_READER);
1758 loop:
1759 for (sp = si_cachea[SI_HASH(spi->s_signature)]; sp; sp = sp->s_next) {
1760 if (sp->s_signature == spi->s_signature &&
1761 sp->s_dev == spi->s_dev &&
1762 sp->s_use > 0 && /* deleting */
1763 sp->s_use <= (MAXLINK - 1) && /* Too many links */
1764 !si_cmp(sp, spi))
1765 break;
1766 }
1767
1768 if (sp == NULL) {
1769 /* Cache miss */
1770 rw_exit(&si_cache_lock);
1771 return (1);
1772 }
1773 /* Found it */
1774 rw_enter(&sp->s_lock, RW_WRITER);
1775 alldone:
1776 spi->s_shadow = sp->s_shadow; /* XXX For debugging */
1777 rw_exit(&si_cache_lock);
1778 *spp = sp;
1779 return (0);
1780 }
1781
1782 /*
1783 * Place an si structure in the si cache. May cause duplicates.
1784 *
1785 * Parameters:
1786 * sp - Ptr to the si struct to add to the cache.
1787 *
1788 * Returns: Nothing (void)
1789 */
1790 static void
si_cache_put(si_t * sp)1791 si_cache_put(si_t *sp)
1792 {
1793 si_t **tspp;
1794
1795 ASSERT(sp->s_fore == NULL);
1796 rw_enter(&si_cache_lock, RW_WRITER);
1797 if (!sp->s_signature)
1798 sp->s_signature = si_signature(sp);
1799 sp->s_flags |= SI_CACHED;
1800 sp->s_fore = NULL;
1801
1802 /* The 'by acl' chains */
1803 tspp = &si_cachea[SI_HASH(sp->s_signature)];
1804 sp->s_next = *tspp;
1805 *tspp = sp;
1806
1807 /* The 'by inode' chains */
1808 tspp = &si_cachei[SI_HASH(sp->s_shadow)];
1809 sp->s_forw = *tspp;
1810 *tspp = sp;
1811
1812 rw_exit(&si_cache_lock);
1813 }
1814
1815 /*
1816 * The sp passed in is a candidate for deletion from the cache. We acquire
1817 * the cache lock first, so no cache searches can be done. Then we search
1818 * for the acl in the cache, and if we find it we can lock it and check that
1819 * nobody else attached to it while we were acquiring the locks. If the acl
1820 * is in the cache and still has a zero reference count, then we remove it
1821 * from the cache and deallocate it. If the reference count is non-zero or
1822 * it is not found in the cache, then someone else attached to it or has
1823 * already freed it, so we just return.
1824 *
1825 * Parameters:
1826 * sp - Ptr to the sp struct which is the candicate for deletion.
1827 * signature - the signature for the acl for lookup in the hash table
1828 *
1829 * Returns: Nothing (void)
1830 */
1831 void
si_cache_del(si_t * sp,int signature)1832 si_cache_del(si_t *sp, int signature)
1833 {
1834 si_t **tspp;
1835 int hash;
1836 int foundacl = 0;
1837
1838 /*
1839 * Unlink & free the sp from the other queues, then destroy it.
1840 * Search the 'by acl' chain first, then the 'by inode' chain
1841 * after the acl is locked.
1842 */
1843 rw_enter(&si_cache_lock, RW_WRITER);
1844 hash = SI_HASH(signature);
1845 for (tspp = &si_cachea[hash]; *tspp; tspp = &(*tspp)->s_next) {
1846 if (*tspp == sp) {
1847 /*
1848 * Wait to grab the acl lock until after the acl has
1849 * been found in the cache. Otherwise it might try to
1850 * grab a lock that has already been destroyed, or
1851 * delete an acl that has already been freed.
1852 */
1853 rw_enter(&sp->s_lock, RW_WRITER);
1854 /* See if someone else attached to it */
1855 if (sp->s_ref) {
1856 rw_exit(&sp->s_lock);
1857 rw_exit(&si_cache_lock);
1858 return;
1859 }
1860 ASSERT(sp->s_fore == NULL);
1861 ASSERT(sp->s_flags & SI_CACHED);
1862 foundacl = 1;
1863 *tspp = sp->s_next;
1864 break;
1865 }
1866 }
1867
1868 /*
1869 * If the acl was not in the cache, we assume another thread has
1870 * deleted it already. This could happen if another thread attaches to
1871 * the acl and then releases it after this thread has already found the
1872 * reference count to be zero but has not yet taken the cache lock.
1873 * Both threads end up seeing a reference count of zero, and call into
1874 * si_cache_del. See bug 4244827 for details on the race condition.
1875 */
1876 if (foundacl == 0) {
1877 rw_exit(&si_cache_lock);
1878 return;
1879 }
1880
1881 /* Now check the 'by inode' chain */
1882 hash = SI_HASH(sp->s_shadow);
1883 for (tspp = &si_cachei[hash]; *tspp; tspp = &(*tspp)->s_forw) {
1884 if (*tspp == sp) {
1885 *tspp = sp->s_forw;
1886 break;
1887 }
1888 }
1889
1890 /*
1891 * At this point, we can unlock everything because this si
1892 * is no longer in the cache, thus cannot be attached to.
1893 */
1894 rw_exit(&sp->s_lock);
1895 rw_exit(&si_cache_lock);
1896 sp->s_flags &= ~SI_CACHED;
1897 (void) ufs_si_free_mem(sp);
1898 }
1899
1900 /*
1901 * Alloc the hash buckets for the si cache & initialize
1902 * the unreferenced anchor and the cache lock.
1903 */
1904 void
si_cache_init(void)1905 si_cache_init(void)
1906 {
1907 rw_init(&si_cache_lock, NULL, RW_DEFAULT, NULL);
1908
1909 /* The 'by acl' headers */
1910 si_cachea = kmem_zalloc(si_cachecnt * sizeof (si_t *), KM_SLEEP);
1911 /* The 'by inode' headers */
1912 si_cachei = kmem_zalloc(si_cachecnt * sizeof (si_t *), KM_SLEEP);
1913 }
1914
1915 /*
1916 * aclcksum takes an acl and generates a checksum. It takes as input
1917 * the acl to start at.
1918 *
1919 * s_aclp - pointer to starting acl
1920 *
1921 * returns checksum
1922 */
1923 static int
aclcksum(ufs_ic_acl_t * s_aclp)1924 aclcksum(ufs_ic_acl_t *s_aclp)
1925 {
1926 ufs_ic_acl_t *aclp;
1927 int signature = 0;
1928 for (aclp = s_aclp; aclp; aclp = aclp->acl_ic_next) {
1929 signature += aclp->acl_ic_perm;
1930 signature += aclp->acl_ic_who;
1931 }
1932 return (signature);
1933 }
1934
1935 /*
1936 * Generate a unique signature for an si structure. Used by the
1937 * search routine si_cachea_get() to quickly identify candidates
1938 * prior to calling si_cmp().
1939 * Parameters:
1940 * sp - Ptr to the si struct to generate the signature for.
1941 *
1942 * Returns: A signature for the si struct (really a checksum)
1943 */
1944 static int
si_signature(si_t * sp)1945 si_signature(si_t *sp)
1946 {
1947 int signature = sp->s_dev;
1948
1949 signature += aclcksum(sp->aowner) + aclcksum(sp->agroup) +
1950 aclcksum(sp->aother) + aclcksum(sp->ausers) +
1951 aclcksum(sp->agroups) + aclcksum(sp->downer) +
1952 aclcksum(sp->dgroup) + aclcksum(sp->dother) +
1953 aclcksum(sp->dusers) + aclcksum(sp->dgroups);
1954 if (sp->aclass.acl_ismask)
1955 signature += sp->aclass.acl_maskbits;
1956 if (sp->dclass.acl_ismask)
1957 signature += sp->dclass.acl_maskbits;
1958
1959 return (signature);
1960 }
1961
1962 /*
1963 * aclcmp compares to acls to see if they are identical.
1964 *
1965 * sp1 is source
1966 * sp2 is sourceb
1967 *
1968 * returns 0 if equal and 1 if not equal
1969 */
1970 static int
aclcmp(ufs_ic_acl_t * aclin1p,ufs_ic_acl_t * aclin2p)1971 aclcmp(ufs_ic_acl_t *aclin1p, ufs_ic_acl_t *aclin2p)
1972 {
1973 ufs_ic_acl_t *aclp1;
1974 ufs_ic_acl_t *aclp2;
1975
1976 /*
1977 * if the starting pointers are equal then they are equal so
1978 * just return.
1979 */
1980 if (aclin1p == aclin2p)
1981 return (0);
1982 /*
1983 * check element by element
1984 */
1985 for (aclp1 = aclin1p, aclp2 = aclin2p; aclp1 && aclp2;
1986 aclp1 = aclp1->acl_ic_next, aclp2 = aclp2->acl_ic_next) {
1987 if (aclp1->acl_ic_perm != aclp2->acl_ic_perm ||
1988 aclp1->acl_ic_who != aclp2->acl_ic_who)
1989 return (1);
1990 }
1991 /*
1992 * both must be zero (at the end of the acl)
1993 */
1994 if (aclp1 || aclp2)
1995 return (1);
1996
1997 return (0);
1998 }
1999
2000 /*
2001 * Do extensive, field-by-field compare of two si structures. Returns
2002 * 0 if they are exactly identical, 1 otherwise.
2003 *
2004 * Paramters:
2005 * sp1 - Ptr to 1st si struct
2006 * sp2 - Ptr to 2nd si struct
2007 *
2008 * Returns:
2009 * 0 - Not identical
2010 * 1 - Identical
2011 */
2012 static int
si_cmp(si_t * sp1,si_t * sp2)2013 si_cmp(si_t *sp1, si_t *sp2)
2014 {
2015 if (sp1->s_dev != sp2->s_dev)
2016 return (1);
2017 if (aclcmp(sp1->aowner, sp2->aowner) ||
2018 aclcmp(sp1->agroup, sp2->agroup) ||
2019 aclcmp(sp1->aother, sp2->aother) ||
2020 aclcmp(sp1->ausers, sp2->ausers) ||
2021 aclcmp(sp1->agroups, sp2->agroups) ||
2022 aclcmp(sp1->downer, sp2->downer) ||
2023 aclcmp(sp1->dgroup, sp2->dgroup) ||
2024 aclcmp(sp1->dother, sp2->dother) ||
2025 aclcmp(sp1->dusers, sp2->dusers) ||
2026 aclcmp(sp1->dgroups, sp2->dgroups))
2027 return (1);
2028 if (sp1->aclass.acl_ismask != sp2->aclass.acl_ismask)
2029 return (1);
2030 if (sp1->dclass.acl_ismask != sp2->dclass.acl_ismask)
2031 return (1);
2032 if (sp1->aclass.acl_ismask &&
2033 sp1->aclass.acl_maskbits != sp2->aclass.acl_maskbits)
2034 return (1);
2035 if (sp1->dclass.acl_ismask &&
2036 sp1->dclass.acl_maskbits != sp2->dclass.acl_maskbits)
2037 return (1);
2038
2039 return (0);
2040 }
2041
2042 /*
2043 * Remove all acls associated with a device. All acls must have
2044 * a reference count of zero.
2045 *
2046 * inputs:
2047 * device - device to remove from the cache
2048 *
2049 * outputs:
2050 * none
2051 */
2052 void
ufs_si_cache_flush(dev_t dev)2053 ufs_si_cache_flush(dev_t dev)
2054 {
2055 si_t *tsp, **tspp;
2056 int i;
2057
2058 rw_enter(&si_cache_lock, RW_WRITER);
2059 for (i = 0; i < si_cachecnt; i++) {
2060 tspp = &si_cachea[i];
2061 while (*tspp) {
2062 if ((*tspp)->s_dev == dev) {
2063 *tspp = (*tspp)->s_next;
2064 } else {
2065 tspp = &(*tspp)->s_next;
2066 }
2067 }
2068 }
2069 for (i = 0; i < si_cachecnt; i++) {
2070 tspp = &si_cachei[i];
2071 while (*tspp) {
2072 if ((*tspp)->s_dev == dev) {
2073 tsp = *tspp;
2074 *tspp = (*tspp)->s_forw;
2075 tsp->s_flags &= ~SI_CACHED;
2076 ufs_si_free_mem(tsp);
2077 } else {
2078 tspp = &(*tspp)->s_forw;
2079 }
2080 }
2081 }
2082 rw_exit(&si_cache_lock);
2083 }
2084
2085 /*
2086 * ufs_si_del is used to unhook a sp from a inode in memory
2087 *
2088 * ip is the inode to remove the sp from.
2089 */
2090 void
ufs_si_del(struct inode * ip)2091 ufs_si_del(struct inode *ip)
2092 {
2093 si_t *sp = ip->i_ufs_acl;
2094 int refcnt;
2095 int signature;
2096
2097 if (sp) {
2098 rw_enter(&sp->s_lock, RW_WRITER);
2099 refcnt = --sp->s_ref;
2100 signature = sp->s_signature;
2101 ASSERT(sp->s_ref >= 0 && sp->s_ref <= sp->s_use);
2102 rw_exit(&sp->s_lock);
2103 if (refcnt == 0)
2104 si_cache_del(sp, signature);
2105 ip->i_ufs_acl = NULL;
2106 }
2107 }
2108