xref: /titanic_41/usr/src/lib/smbsrv/libsmb/common/smb_sd.c (revision ae3d7f90695ef456a6da4f7bdccd448ebe0b99e1)
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 /*
23  * Copyright (c) 2009, 2010, Oracle and/or its affiliates. All rights reserved.
24  */
25 
26 /*
27  * This module provides Security Descriptor handling functions.
28  */
29 
30 #include <strings.h>
31 #include <assert.h>
32 #include <errno.h>
33 #include <smbsrv/ntifs.h>
34 #include <smbsrv/smb_idmap.h>
35 #include <smbsrv/libsmb.h>
36 
37 #define	SMB_SHR_ACE_READ_PERMS	(ACE_READ_PERMS | ACE_EXECUTE | ACE_SYNCHRONIZE)
38 #define	SMB_SHR_ACE_CONTROL_PERMS	(ACE_MODIFY_PERMS & (~ACE_DELETE_CHILD))
39 
40 /*
41  * This mapping table is provided to map permissions set by chmod
42  * using 'read_set' and 'modify_set' to what Windows share ACL GUI
43  * expects as Read and Control, respectively.
44  */
45 static struct {
46 	int am_ace_perms;
47 	int am_share_perms;
48 } smb_ace_map[] = {
49 	{ ACE_MODIFY_PERMS,	SMB_SHR_ACE_CONTROL_PERMS },
50 	{ ACE_READ_PERMS,	SMB_SHR_ACE_READ_PERMS }
51 };
52 
53 #define	SMB_ACE_MASK_MAP_SIZE	(sizeof (smb_ace_map)/sizeof (smb_ace_map[0]))
54 
55 static void smb_sd_set_sacl(smb_sd_t *, smb_acl_t *, boolean_t, int);
56 static void smb_sd_set_dacl(smb_sd_t *, smb_acl_t *, boolean_t, int);
57 
58 void
59 smb_sd_init(smb_sd_t *sd, uint8_t revision)
60 {
61 	bzero(sd, sizeof (smb_sd_t));
62 	sd->sd_revision = revision;
63 }
64 
65 /*
66  * smb_sd_term
67  *
68  * Free non-NULL members of 'sd' which has to be in
69  * absolute (pointer) form.
70  */
71 void
72 smb_sd_term(smb_sd_t *sd)
73 {
74 	assert(sd);
75 	assert((sd->sd_control & SE_SELF_RELATIVE) == 0);
76 
77 	smb_sid_free(sd->sd_owner);
78 	smb_sid_free(sd->sd_group);
79 	smb_acl_free(sd->sd_dacl);
80 	smb_acl_free(sd->sd_sacl);
81 
82 	bzero(sd, sizeof (smb_sd_t));
83 }
84 
85 uint32_t
86 smb_sd_len(smb_sd_t *sd, uint32_t secinfo)
87 {
88 	uint32_t length = SMB_SD_HDRSIZE;
89 
90 	if (secinfo & SMB_OWNER_SECINFO)
91 		length += smb_sid_len(sd->sd_owner);
92 
93 	if (secinfo & SMB_GROUP_SECINFO)
94 		length += smb_sid_len(sd->sd_group);
95 
96 	if (secinfo & SMB_DACL_SECINFO)
97 		length += smb_acl_len(sd->sd_dacl);
98 
99 	if (secinfo & SMB_SACL_SECINFO)
100 		length += smb_acl_len(sd->sd_sacl);
101 
102 	return (length);
103 }
104 
105 /*
106  * smb_sd_get_secinfo
107  *
108  * Return the security information mask for the specified security
109  * descriptor.
110  */
111 uint32_t
112 smb_sd_get_secinfo(smb_sd_t *sd)
113 {
114 	uint32_t sec_info = 0;
115 
116 	if (sd == NULL)
117 		return (0);
118 
119 	if (sd->sd_owner)
120 		sec_info |= SMB_OWNER_SECINFO;
121 
122 	if (sd->sd_group)
123 		sec_info |= SMB_GROUP_SECINFO;
124 
125 	if (sd->sd_dacl)
126 		sec_info |= SMB_DACL_SECINFO;
127 
128 	if (sd->sd_sacl)
129 		sec_info |= SMB_SACL_SECINFO;
130 
131 	return (sec_info);
132 }
133 
134 /*
135  * Adjust the Access Mask so that ZFS ACE mask and Windows ACE read mask match.
136  */
137 static int
138 smb_sd_adjust_read_mask(int mask)
139 {
140 	int i;
141 
142 	for (i = 0; i < SMB_ACE_MASK_MAP_SIZE; ++i) {
143 		if (smb_ace_map[i].am_ace_perms == mask)
144 			return (smb_ace_map[i].am_share_perms);
145 	}
146 
147 	return (mask);
148 }
149 
150 /*
151  * Get ZFS acl from the share path via acl_get() method.
152  */
153 static uint32_t
154 smb_sd_read_acl(char *path, smb_fssd_t *fs_sd)
155 {
156 	acl_t *z_acl;
157 	ace_t *z_ace;
158 
159 	fs_sd->sd_gid = fs_sd->sd_uid = 0;
160 
161 	errno = 0;
162 	if (acl_get(path, 0, &z_acl) != 0) {
163 		switch (errno) {
164 		case EACCES:
165 			return (NT_STATUS_ACCESS_DENIED);
166 		case ENOENT:
167 			return (NT_STATUS_OBJECT_PATH_NOT_FOUND);
168 		default:
169 			return (NT_STATUS_INTERNAL_ERROR);
170 		}
171 	}
172 
173 	if ((z_ace = (ace_t *)z_acl->acl_aclp) == NULL)
174 		return (NT_STATUS_INVALID_ACL);
175 
176 	for (int i = 0; i < z_acl->acl_cnt; i++, z_ace++)
177 		z_ace->a_access_mask =
178 		    smb_sd_adjust_read_mask(z_ace->a_access_mask);
179 
180 	fs_sd->sd_zdacl = z_acl;
181 	fs_sd->sd_zsacl = NULL;
182 	return (NT_STATUS_SUCCESS);
183 }
184 
185 /*
186  * smb_sd_read
187  *
188  * Reads ZFS acl from filesystem using acl_get() method. Convert the ZFS acl to
189  * a Win SD and return the Win SD in absolute form.
190  *
191  * NOTE: upon successful return caller MUST free the memory allocated
192  * for the returned SD by calling smb_sd_term().
193  */
194 uint32_t
195 smb_sd_read(char *path, smb_sd_t *sd, uint32_t secinfo)
196 {
197 	smb_fssd_t fs_sd;
198 	uint32_t status = NT_STATUS_SUCCESS;
199 	uint32_t sd_flags;
200 	int error;
201 
202 	sd_flags = SMB_FSSD_FLAGS_DIR;
203 	smb_fssd_init(&fs_sd, secinfo, sd_flags);
204 
205 	error = smb_sd_read_acl(path, &fs_sd);
206 	if (error != NT_STATUS_SUCCESS) {
207 		smb_fssd_term(&fs_sd);
208 		return (error);
209 	}
210 
211 	status = smb_sd_fromfs(&fs_sd, sd);
212 	smb_fssd_term(&fs_sd);
213 
214 	return (status);
215 }
216 
217 /*
218  * Apply ZFS acl to the share path via acl_set() method.
219  * A NULL ACL pointer here represents an error.
220  * Null or empty ACLs are handled in smb_sd_tofs().
221  */
222 static uint32_t
223 smb_sd_write_acl(char *path, smb_fssd_t *fs_sd)
224 {
225 	acl_t *z_acl;
226 	ace_t *z_ace;
227 	uint32_t status = NT_STATUS_SUCCESS;
228 
229 	z_acl = fs_sd->sd_zdacl;
230 	if (z_acl == NULL)
231 		return (NT_STATUS_INVALID_ACL);
232 
233 	z_ace = (ace_t *)z_acl->acl_aclp;
234 	if (z_ace == NULL)
235 		return (NT_STATUS_INVALID_ACL);
236 
237 	fs_sd->sd_gid = fs_sd->sd_uid = 0;
238 	if (acl_set(path, z_acl) != 0)
239 		status = NT_STATUS_INTERNAL_ERROR;
240 
241 	return (status);
242 }
243 
244 /*
245  * smb_sd_write
246  *
247  * Takes a Win SD in absolute form, converts it to
248  * ZFS acl and applies the acl to the share path via acl_set() method.
249  */
250 uint32_t
251 smb_sd_write(char *path, smb_sd_t *sd, uint32_t secinfo)
252 {
253 	smb_fssd_t fs_sd;
254 	uint32_t status = NT_STATUS_SUCCESS;
255 	uint32_t sd_flags;
256 	int error;
257 
258 	sd_flags = SMB_FSSD_FLAGS_DIR;
259 	smb_fssd_init(&fs_sd, secinfo, sd_flags);
260 
261 	error = smb_sd_tofs(sd, &fs_sd);
262 	if (error != NT_STATUS_SUCCESS) {
263 		smb_fssd_term(&fs_sd);
264 		return (error);
265 	}
266 
267 	status = smb_sd_write_acl(path, &fs_sd);
268 	smb_fssd_term(&fs_sd);
269 
270 	return (status);
271 }
272 
273 /*
274  * smb_sd_tofs
275  *
276  * Creates a filesystem security structure based on the given
277  * Windows security descriptor.
278  */
279 uint32_t
280 smb_sd_tofs(smb_sd_t *sd, smb_fssd_t *fs_sd)
281 {
282 	smb_sid_t *sid;
283 	uint32_t status = NT_STATUS_SUCCESS;
284 	uint16_t sd_control;
285 	idmap_stat idm_stat;
286 	int idtype;
287 	int flags = 0;
288 
289 	sd_control = sd->sd_control;
290 
291 	/*
292 	 * ZFS only has one set of flags so for now only
293 	 * Windows DACL flags are taken into account.
294 	 */
295 	if (sd_control & SE_DACL_DEFAULTED)
296 		flags |= ACL_DEFAULTED;
297 	if (sd_control & SE_DACL_AUTO_INHERITED)
298 		flags |= ACL_AUTO_INHERIT;
299 	if (sd_control & SE_DACL_PROTECTED)
300 		flags |= ACL_PROTECTED;
301 
302 	if (fs_sd->sd_flags & SMB_FSSD_FLAGS_DIR)
303 		flags |= ACL_IS_DIR;
304 
305 	/* Owner */
306 	if (fs_sd->sd_secinfo & SMB_OWNER_SECINFO) {
307 		sid = sd->sd_owner;
308 		if (!smb_sid_isvalid(sid))
309 			return (NT_STATUS_INVALID_SID);
310 
311 		idtype = SMB_IDMAP_USER;
312 		idm_stat = smb_idmap_getid(sid, &fs_sd->sd_uid, &idtype);
313 		if (idm_stat != IDMAP_SUCCESS) {
314 			return (NT_STATUS_NONE_MAPPED);
315 		}
316 	}
317 
318 	/* Group */
319 	if (fs_sd->sd_secinfo & SMB_GROUP_SECINFO) {
320 		sid = sd->sd_group;
321 		if (!smb_sid_isvalid(sid))
322 			return (NT_STATUS_INVALID_SID);
323 
324 		idtype = SMB_IDMAP_GROUP;
325 		idm_stat = smb_idmap_getid(sid, &fs_sd->sd_gid, &idtype);
326 		if (idm_stat != IDMAP_SUCCESS) {
327 			return (NT_STATUS_NONE_MAPPED);
328 		}
329 	}
330 
331 	/* DACL */
332 	if (fs_sd->sd_secinfo & SMB_DACL_SECINFO) {
333 		if (sd->sd_control & SE_DACL_PRESENT) {
334 			status = smb_acl_to_zfs(sd->sd_dacl, flags,
335 			    SMB_DACL_SECINFO, &fs_sd->sd_zdacl);
336 			if (status != NT_STATUS_SUCCESS)
337 				return (status);
338 		}
339 		else
340 			return (NT_STATUS_INVALID_ACL);
341 	}
342 
343 	/* SACL */
344 	if (fs_sd->sd_secinfo & SMB_SACL_SECINFO) {
345 		if (sd->sd_control & SE_SACL_PRESENT) {
346 			status = smb_acl_to_zfs(sd->sd_sacl, flags,
347 			    SMB_SACL_SECINFO, &fs_sd->sd_zsacl);
348 			if (status != NT_STATUS_SUCCESS) {
349 				return (status);
350 			}
351 		} else {
352 			return (NT_STATUS_INVALID_ACL);
353 		}
354 	}
355 
356 	return (status);
357 }
358 
359 /*
360  * smb_sd_fromfs
361  *
362  * Makes an Windows style security descriptor in absolute form
363  * based on the given filesystem security information.
364  *
365  * Should call smb_sd_term() for the returned sd to free allocated
366  * members.
367  */
368 uint32_t
369 smb_sd_fromfs(smb_fssd_t *fs_sd, smb_sd_t *sd)
370 {
371 	uint32_t status = NT_STATUS_SUCCESS;
372 	smb_acl_t *acl = NULL;
373 	smb_sid_t *sid;
374 	idmap_stat idm_stat;
375 
376 	assert(fs_sd);
377 	assert(sd);
378 
379 	smb_sd_init(sd, SECURITY_DESCRIPTOR_REVISION);
380 
381 	/* Owner */
382 	if (fs_sd->sd_secinfo & SMB_OWNER_SECINFO) {
383 		idm_stat = smb_idmap_getsid(fs_sd->sd_uid,
384 		    SMB_IDMAP_USER, &sid);
385 
386 		if (idm_stat != IDMAP_SUCCESS) {
387 			smb_sd_term(sd);
388 			return (NT_STATUS_NONE_MAPPED);
389 		}
390 
391 		sd->sd_owner = sid;
392 	}
393 
394 	/* Group */
395 	if (fs_sd->sd_secinfo & SMB_GROUP_SECINFO) {
396 		idm_stat = smb_idmap_getsid(fs_sd->sd_gid,
397 		    SMB_IDMAP_GROUP, &sid);
398 
399 		if (idm_stat != IDMAP_SUCCESS) {
400 			smb_sd_term(sd);
401 			return (NT_STATUS_NONE_MAPPED);
402 		}
403 
404 		sd->sd_group = sid;
405 	}
406 
407 	/* DACL */
408 	if (fs_sd->sd_secinfo & SMB_DACL_SECINFO) {
409 		if (fs_sd->sd_zdacl != NULL) {
410 			acl = smb_acl_from_zfs(fs_sd->sd_zdacl);
411 			if (acl == NULL) {
412 				smb_sd_term(sd);
413 				return (NT_STATUS_INTERNAL_ERROR);
414 			}
415 
416 			/*
417 			 * Need to sort the ACL before send it to Windows
418 			 * clients. Winodws GUI is sensitive about the order
419 			 * of ACEs.
420 			 */
421 			smb_acl_sort(acl);
422 			smb_sd_set_dacl(sd, acl, B_TRUE,
423 			    fs_sd->sd_zdacl->acl_flags);
424 		} else {
425 			smb_sd_set_dacl(sd, NULL, B_FALSE, 0);
426 		}
427 	}
428 
429 	/* SACL */
430 	if (fs_sd->sd_secinfo & SMB_SACL_SECINFO) {
431 		if (fs_sd->sd_zsacl != NULL) {
432 			acl = smb_acl_from_zfs(fs_sd->sd_zsacl);
433 			if (acl == NULL) {
434 				smb_sd_term(sd);
435 				return (NT_STATUS_INTERNAL_ERROR);
436 			}
437 
438 			smb_sd_set_sacl(sd, acl, B_TRUE,
439 			    fs_sd->sd_zsacl->acl_flags);
440 		} else {
441 			smb_sd_set_sacl(sd, NULL, B_FALSE, 0);
442 		}
443 	}
444 
445 	return (status);
446 }
447 
448 static void
449 smb_sd_set_dacl(smb_sd_t *sd, smb_acl_t *acl, boolean_t present, int flags)
450 {
451 	assert((sd->sd_control & SE_SELF_RELATIVE) == 0);
452 
453 	sd->sd_dacl = acl;
454 
455 	if (flags & ACL_DEFAULTED)
456 		sd->sd_control |= SE_DACL_DEFAULTED;
457 	if (flags & ACL_AUTO_INHERIT)
458 		sd->sd_control |= SE_DACL_AUTO_INHERITED;
459 	if (flags & ACL_PROTECTED)
460 		sd->sd_control |= SE_DACL_PROTECTED;
461 
462 	if (present)
463 		sd->sd_control |= SE_DACL_PRESENT;
464 }
465 
466 static void
467 smb_sd_set_sacl(smb_sd_t *sd, smb_acl_t *acl, boolean_t present, int flags)
468 {
469 	assert((sd->sd_control & SE_SELF_RELATIVE) == 0);
470 
471 	sd->sd_sacl = acl;
472 
473 	if (flags & ACL_DEFAULTED)
474 		sd->sd_control |= SE_SACL_DEFAULTED;
475 	if (flags & ACL_AUTO_INHERIT)
476 		sd->sd_control |= SE_SACL_AUTO_INHERITED;
477 	if (flags & ACL_PROTECTED)
478 		sd->sd_control |= SE_SACL_PROTECTED;
479 
480 	if (present)
481 		sd->sd_control |= SE_SACL_PRESENT;
482 }
483 
484 /*
485  * smb_fssd_init
486  *
487  * Initializes the given FS SD structure.
488  */
489 void
490 smb_fssd_init(smb_fssd_t *fs_sd, uint32_t secinfo, uint32_t flags)
491 {
492 	bzero(fs_sd, sizeof (smb_fssd_t));
493 	fs_sd->sd_secinfo = secinfo;
494 	fs_sd->sd_flags = flags;
495 }
496 
497 /*
498  * smb_fssd_term
499  *
500  * Frees allocated memory for acl fields.
501  */
502 void
503 smb_fssd_term(smb_fssd_t *fs_sd)
504 {
505 	assert(fs_sd);
506 
507 	acl_free(fs_sd->sd_zdacl);
508 	acl_free(fs_sd->sd_zsacl);
509 
510 	bzero(fs_sd, sizeof (smb_fssd_t));
511 }
512