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 (c) 2006, 2010, Oracle and/or its affiliates. All rights reserved.
23 */
24
25 #include <sys/types.h>
26 #include <sys/param.h>
27 #include <sys/cmn_err.h>
28 #include <sys/systm.h>
29 #include <sys/cred.h>
30 #include <sys/modctl.h>
31 #include <sys/vfs.h>
32 #include <sys/vnode.h>
33 #include <sys/tiuser.h>
34 #include <sys/kmem.h>
35 #include <sys/pathname.h>
36 #include <sys/zone.h>
37 #include <sys/tsol/label.h>
38 #include <sys/tsol/tnet.h>
39 #include <sys/fs/lofs_node.h>
40 #include <sys/fs/zfs.h>
41 #include <sys/dsl_prop.h>
42 #include <inet/ip6.h>
43 #include <rpc/auth.h>
44 #include <rpc/clnt.h>
45 #include <nfs/nfs.h>
46 #include <nfs/nfs4.h>
47 #include <nfs/nfs_clnt.h>
48
49
50 int sys_labeling = 0; /* the default is "off" */
51
52 static kmem_cache_t *tslabel_cache;
53 ts_label_t *l_admin_low;
54 ts_label_t *l_admin_high;
55
56 uint32_t default_doi = DEFAULT_DOI;
57
58 /*
59 * Initialize labels infrastructure.
60 * This is called during startup() time (before vfs_mntroot) by thread_init().
61 * It has to be called early so that the is_system_labeled() function returns
62 * the right value when called by the networking code on a diskless boot.
63 */
64 void
65 label_init(void)
66 {
67 bslabel_t label;
68
69 /*
70 * sys_labeling will default to "off" unless it is overridden
71 * in /etc/system.
72 */
73
74 tslabel_cache = kmem_cache_create("tslabel_cache", sizeof (ts_label_t),
75 0, NULL, NULL, NULL, NULL, NULL, 0);
76 bsllow(&label);
77 l_admin_low = labelalloc(&label, default_doi, KM_SLEEP);
78 bslhigh(&label);
79 l_admin_high = labelalloc(&label, default_doi, KM_SLEEP);
80 }
81
82 /*
83 * Allocate new ts_label_t.
84 */
85 ts_label_t *
86 labelalloc(const bslabel_t *val, uint32_t doi, int flag)
87 {
88 ts_label_t *lab = kmem_cache_alloc(tslabel_cache, flag);
89
90 if (lab != NULL) {
91 lab->tsl_ref = 1;
92 lab->tsl_doi = doi;
93 lab->tsl_flags = 0;
94 if (val == NULL)
95 bzero(&lab->tsl_label, sizeof (bslabel_t));
96 else
97 bcopy(val, &lab->tsl_label, sizeof (bslabel_t));
98 }
99 return (lab);
100 }
101
102 /*
103 * Duplicate an existing ts_label_t to a new one, with only
104 * the current reference.
105 */
106 ts_label_t *
107 labeldup(const ts_label_t *val, int flag)
108 {
109 ts_label_t *lab = kmem_cache_alloc(tslabel_cache, flag);
110
111 if (lab != NULL) {
112 bcopy(val, lab, sizeof (ts_label_t));
113 lab->tsl_ref = 1;
114 }
115 return (lab);
116 }
117
118 /*
119 * Put a hold on a label structure.
120 */
121 void
122 label_hold(ts_label_t *lab)
123 {
124 atomic_inc_32(&lab->tsl_ref);
125 }
126
127 /*
128 * Release previous hold on a label structure. Free it if refcnt == 0.
129 */
130 void
131 label_rele(ts_label_t *lab)
132 {
133 if (atomic_dec_32_nv(&lab->tsl_ref) == 0)
134 kmem_cache_free(tslabel_cache, lab);
135 }
136
137 bslabel_t *
138 label2bslabel(ts_label_t *lab)
139 {
140 return (&lab->tsl_label);
141 }
142
143
144 uint32_t
145 label2doi(ts_label_t *lab)
146 {
147 return (lab->tsl_doi);
148 }
149
150 /*
151 * Compare labels. Return 1 if equal, 0 otherwise.
152 */
153 boolean_t
154 label_equal(const ts_label_t *l1, const ts_label_t *l2)
155 {
156 return ((l1->tsl_doi == l2->tsl_doi) &&
157 blequal(&l1->tsl_label, &l2->tsl_label));
158 }
159
160 /*
161 * There's no protocol today to obtain the label from the server.
162 * So we rely on conventions: zones, zone names, and zone paths
163 * must match across TX servers and their TX clients. Now use
164 * the exported name to find the equivalent local zone and its
165 * label. Caller is responsible for doing a label_rele of the
166 * returned ts_label.
167 */
168 ts_label_t *
169 getflabel_cipso(vfs_t *vfsp)
170 {
171 zone_t *reszone;
172 zone_t *new_reszone;
173 char *nfspath, *respath;
174 refstr_t *resource_ref;
175 boolean_t treat_abs = B_FALSE;
176
177 if (vfsp->vfs_resource == NULL)
178 return (NULL); /* error */
179 resource_ref = vfs_getresource(vfsp);
180
181 nfspath = (char *)refstr_value(resource_ref);
182 respath = strchr(nfspath, ':'); /* skip server name */
183 if (respath)
184 respath++; /* skip over ":" */
185 if (*respath != '/') {
186 /* treat path as absolute but it doesn't have leading '/' */
187 treat_abs = B_TRUE;
188 }
189
190 reszone = zone_find_by_any_path(respath, treat_abs);
191 if (reszone == global_zone) {
192 refstr_rele(resource_ref);
193 label_hold(l_admin_low);
194 zone_rele(reszone);
195 return (l_admin_low);
196 }
197
198 /*
199 * Skip over zonepath (not including "root"), e.g. /zone/internal
200 */
201 respath += reszone->zone_rootpathlen - 7;
202 if (treat_abs)
203 respath--; /* no leading '/' to skip */
204 if (strncmp(respath, "/root/", 6) == 0) {
205 /* Check if we now have something like "/zone/public/" */
206
207 respath += 5; /* skip "/root" first */
208 new_reszone = zone_find_by_any_path(respath, B_FALSE);
209 if (new_reszone != global_zone) {
210 zone_rele(reszone);
211 reszone = new_reszone;
212 } else {
213 zone_rele(new_reszone);
214 }
215 }
216
217 refstr_rele(resource_ref);
218 label_hold(reszone->zone_slabel);
219 zone_rele(reszone);
220
221 return (reszone->zone_slabel);
222 }
223
224 /*
225 * Get the label if any of a zfs filesystem. Get the dataset, then
226 * get its mlslabel property, convert as needed, and return it. If
227 * there's no mlslabel or it is the default one, return NULL.
228 */
229 static ts_label_t *
230 getflabel_zfs(vfs_t *vfsp)
231 {
232 int error;
233 ts_label_t *tsl = NULL;
234 refstr_t *resource_ref;
235 bslabel_t ds_sl;
236 char ds_hexsl[MAXNAMELEN];
237 const char *osname;
238
239 resource_ref = vfs_getresource(vfsp);
240 osname = refstr_value(resource_ref);
241
242 error = dsl_prop_get(osname, zfs_prop_to_name(ZFS_PROP_MLSLABEL),
243 1, sizeof (ds_hexsl), &ds_hexsl, NULL);
244 refstr_rele(resource_ref);
245
246 if ((error) || (strcasecmp(ds_hexsl, ZFS_MLSLABEL_DEFAULT) == 0))
247 return (NULL);
248 if (hexstr_to_label(ds_hexsl, &ds_sl) != 0)
249 return (NULL);
250
251 tsl = labelalloc(&ds_sl, default_doi, KM_SLEEP);
252 return (tsl);
253 }
254
255 static ts_label_t *
256 getflabel_nfs(vfs_t *vfsp)
257 {
258 bslabel_t *server_sl;
259 ts_label_t *srv_label;
260 tsol_tpc_t *tp;
261 int addr_type;
262 void *ipaddr;
263 struct servinfo *svp;
264 struct netbuf *addr;
265 struct knetconfig *knconf;
266 mntinfo_t *mi;
267
268 mi = VFTOMI(vfsp);
269 svp = mi->mi_curr_serv;
270 addr = &svp->sv_addr;
271 knconf = svp->sv_knconf;
272
273 if (strcmp(knconf->knc_protofmly, NC_INET) == 0) {
274 addr_type = IPV4_VERSION;
275 /* LINTED: following cast to ipaddr is OK */
276 ipaddr = &((struct sockaddr_in *)addr->buf)->sin_addr;
277 } else if (strcmp(knconf->knc_protofmly, NC_INET6) == 0) {
278 addr_type = IPV6_VERSION;
279 /* LINTED: following cast to ipaddr is OK */
280 ipaddr = &((struct sockaddr_in6 *)addr->buf)->sin6_addr;
281 } else {
282 goto errout;
283 }
284
285 tp = find_tpc(ipaddr, addr_type, B_FALSE);
286 if (tp == NULL)
287 goto errout;
288
289 if (tp->tpc_tp.host_type == SUN_CIPSO) {
290 TPC_RELE(tp);
291 return (getflabel_cipso(vfsp));
292 }
293
294 if (tp->tpc_tp.host_type != UNLABELED)
295 goto errout;
296
297 server_sl = &tp->tpc_tp.tp_def_label;
298 srv_label = labelalloc(server_sl, default_doi, KM_SLEEP);
299
300 TPC_RELE(tp);
301
302 return (srv_label);
303
304 errout:
305 return (NULL);
306 }
307
308 /*
309 * getflabel -
310 *
311 * Return pointer to the ts_label associated with the specified file,
312 * or returns NULL if error occurs. Caller is responsible for doing
313 * a label_rele of the ts_label.
314 */
315 ts_label_t *
316 getflabel(vnode_t *vp)
317 {
318 vfs_t *vfsp, *rvfsp;
319 vnode_t *rvp, *rvp2;
320 zone_t *zone;
321 ts_label_t *zl;
322 int err;
323 boolean_t vfs_is_held = B_FALSE;
324 char vpath[MAXPATHLEN];
325
326 ASSERT(vp);
327 vfsp = vp->v_vfsp;
328 if (vfsp == NULL)
329 return (NULL);
330
331 rvp = vp;
332
333 /*
334 * Traverse lofs mounts and fattach'es to get the real vnode
335 */
336 if (VOP_REALVP(rvp, &rvp2, NULL) == 0)
337 rvp = rvp2;
338
339 rvfsp = rvp->v_vfsp;
340
341 /* rvp/rvfsp now represent the real vnode/vfs we will be using */
342
343 /* Go elsewhere to handle all nfs files. */
344 if (strncmp(vfssw[rvfsp->vfs_fstype].vsw_name, "nfs", 3) == 0)
345 return (getflabel_nfs(rvfsp));
346
347 /*
348 * Fast path, for objects in a labeled zone: everything except
349 * for lofs/nfs will be just the label of that zone.
350 */
351 if ((rvfsp->vfs_zone != NULL) && (rvfsp->vfs_zone != global_zone)) {
352 if ((strcmp(vfssw[rvfsp->vfs_fstype].vsw_name,
353 "lofs") != 0)) {
354 zone = rvfsp->vfs_zone;
355 zone_hold(zone);
356 goto zone_out; /* return this label */
357 }
358 }
359
360 /*
361 * Get the vnode path -- it may be missing or weird for some
362 * cases, like devices. In those cases use the label of the
363 * current zone.
364 */
365 err = vnodetopath(rootdir, rvp, vpath, sizeof (vpath), kcred);
366 if ((err != 0) || (*vpath != '/')) {
367 zone = curproc->p_zone;
368 zone_hold(zone);
369 goto zone_out;
370 }
371
372 /*
373 * For zfs filesystem, return the explicit label property if a
374 * meaningful one exists.
375 */
376 if (strncmp(vfssw[rvfsp->vfs_fstype].vsw_name, "zfs", 3) == 0) {
377 ts_label_t *tsl;
378
379 tsl = getflabel_zfs(rvfsp);
380
381 /* if label found, return it, otherwise continue... */
382 if (tsl != NULL)
383 return (tsl);
384 }
385
386 /*
387 * If a mountpoint exists, hold the vfs while we reference it.
388 * Otherwise if mountpoint is NULL it should not be held (e.g.,
389 * a hold/release on spec_vfs would result in an attempted free
390 * and panic.)
391 */
392 if (vfsp->vfs_mntpt != NULL) {
393 VFS_HOLD(vfsp);
394 vfs_is_held = B_TRUE;
395 }
396
397 zone = zone_find_by_any_path(vpath, B_FALSE);
398
399 /*
400 * If the vnode source zone is properly set to a non-global zone, or
401 * any zone if the mount is R/W, then use the label of that zone.
402 */
403 if ((zone != global_zone) || ((vfsp->vfs_flag & VFS_RDONLY) != 0))
404 goto zone_out; /* return this label */
405
406 /*
407 * Otherwise, if we're not in the global zone, use the label of
408 * our zone.
409 */
410 if ((zone = curproc->p_zone) != global_zone) {
411 zone_hold(zone);
412 goto zone_out; /* return this label */
413 }
414
415 /*
416 * We're in the global zone and the mount is R/W ... so the file
417 * may actually be in the global zone -- or in the root of any zone.
418 * Always build our own path for the file, to be sure it's simplified
419 * (i.e., no ".", "..", "//", and so on).
420 */
421
422 zone_rele(zone);
423 zone = zone_find_by_any_path(vpath, B_FALSE);
424
425 zone_out:
426 if ((curproc->p_zone == global_zone) && (zone == global_zone)) {
427 vfs_t *nvfs;
428 boolean_t exported = B_FALSE;
429 refstr_t *mntpt_ref;
430 char *mntpt;
431
432 /*
433 * File is in the global zone - check whether it's admin_high.
434 * If it's in a filesys that was exported from the global zone,
435 * it's admin_low by definition. Otherwise, if it's in a
436 * filesys that's NOT exported to any zone, it's admin_high.
437 *
438 * And for these files if there wasn't a valid mount resource,
439 * the file must be admin_high (not exported, probably a global
440 * zone device).
441 */
442 if (!vfs_is_held)
443 goto out_high;
444
445 mntpt_ref = vfs_getmntpoint(vfsp);
446 mntpt = (char *)refstr_value(mntpt_ref);
447
448 if ((mntpt != NULL) && (*mntpt == '/')) {
449 zone_t *to_zone;
450
451 to_zone = zone_find_by_any_path(mntpt, B_FALSE);
452 zone_rele(to_zone);
453 if (to_zone != global_zone) {
454 /* force admin_low */
455 exported = B_TRUE;
456 }
457 }
458 if (mntpt_ref)
459 refstr_rele(mntpt_ref);
460
461 if (!exported) {
462 size_t plen = strlen(vpath);
463
464 vfs_list_read_lock();
465 nvfs = vfsp->vfs_next;
466 while (nvfs != vfsp) {
467 const char *rstr;
468 size_t rlen = 0;
469
470 /*
471 * Skip checking this vfs if it's not lofs
472 * (the only way to export from the global
473 * zone to a zone).
474 */
475 if (strncmp(vfssw[nvfs->vfs_fstype].vsw_name,
476 "lofs", 4) != 0) {
477 nvfs = nvfs->vfs_next;
478 continue;
479 }
480
481 rstr = refstr_value(nvfs->vfs_resource);
482 if (rstr != NULL)
483 rlen = strlen(rstr);
484
485 /*
486 * Check for a match: does this vfs correspond
487 * to our global zone file path? I.e., check
488 * if the resource string of this vfs is a
489 * prefix of our path.
490 */
491 if ((rlen > 0) && (rlen <= plen) &&
492 (strncmp(rstr, vpath, rlen) == 0) &&
493 (vpath[rlen] == '/' ||
494 vpath[rlen] == '\0')) {
495 /* force admin_low */
496 exported = B_TRUE;
497 break;
498 }
499 nvfs = nvfs->vfs_next;
500 }
501 vfs_list_unlock();
502 }
503
504 if (!exported)
505 goto out_high;
506 }
507
508 if (vfs_is_held)
509 VFS_RELE(vfsp);
510
511 /*
512 * Now that we have the "home" zone for the file, return the slabel
513 * of that zone.
514 */
515 zl = zone->zone_slabel;
516 label_hold(zl);
517 zone_rele(zone);
518 return (zl);
519
520 out_high:
521 if (vfs_is_held)
522 VFS_RELE(vfsp);
523
524 label_hold(l_admin_high);
525 zone_rele(zone);
526 return (l_admin_high);
527 }
528
529 static int
530 cgetlabel(bslabel_t *label_p, vnode_t *vp)
531 {
532 ts_label_t *tsl;
533 int error = 0;
534
535 if ((tsl = getflabel(vp)) == NULL)
536 return (EIO);
537
538 if (copyout((caddr_t)label2bslabel(tsl), (caddr_t)label_p,
539 sizeof (*(label_p))) != 0)
540 error = EFAULT;
541
542 label_rele(tsl);
543 return (error);
544 }
545
546 /*
547 * fgetlabel(2TSOL) - get file label
548 * getlabel(2TSOL) - get file label
549 */
550 int
551 getlabel(const char *path, bslabel_t *label_p)
552 {
553 struct vnode *vp;
554 char *spath;
555 int error;
556
557 /* Sanity check arguments */
558 if (path == NULL)
559 return (set_errno(EINVAL));
560
561 spath = kmem_zalloc(MAXPATHLEN, KM_SLEEP);
562 if ((error = copyinstr(path, spath, MAXPATHLEN, NULL)) != 0) {
563 kmem_free(spath, MAXPATHLEN);
564 return (set_errno(error));
565 }
566
567 if (error = lookupname(spath, UIO_SYSSPACE, FOLLOW, NULLVPP, &vp)) {
568 kmem_free(spath, MAXPATHLEN);
569 return (set_errno(error));
570 }
571 kmem_free(spath, MAXPATHLEN);
572
573 error = cgetlabel(label_p, vp);
574
575 VN_RELE(vp);
576 if (error != 0)
577 return (set_errno(error));
578 else
579 return (0);
580 }
581
582 int
583 fgetlabel(int fd, bslabel_t *label_p)
584 {
585 file_t *fp;
586 int error;
587
588 if ((fp = getf(fd)) == NULL)
589 return (set_errno(EBADF));
590
591 error = cgetlabel(label_p, fp->f_vnode);
592 releasef(fd);
593
594 if (error != 0)
595 return (set_errno(error));
596 else
597 return (0);
598 }