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Josef Bacik5103e942007-11-16 11:45:54 -05001/*
2 * Copyright (C) 2007 Red Hat. All rights reserved.
3 *
4 * This program is free software; you can redistribute it and/or
5 * modify it under the terms of the GNU General Public
6 * License v2 as published by the Free Software Foundation.
7 *
8 * This program is distributed in the hope that it will be useful,
9 * but WITHOUT ANY WARRANTY; without even the implied warranty of
10 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
11 * General Public License for more details.
12 *
13 * You should have received a copy of the GNU General Public
14 * License along with this program; if not, write to the
15 * Free Software Foundation, Inc., 59 Temple Place - Suite 330,
16 * Boston, MA 021110-1307, USA.
17 */
18
19#include <linux/fs.h>
20#include <linux/string.h>
21#include <linux/xattr.h>
22#include <linux/posix_acl_xattr.h>
Josef Bacik33268ea2008-07-24 12:16:36 -040023#include <linux/posix_acl.h>
Chris Masonc1e32da2008-01-22 12:46:56 -050024#include <linux/sched.h>
Tejun Heo5a0e3ad2010-03-24 17:04:11 +090025#include <linux/slab.h>
Josef Bacik33268ea2008-07-24 12:16:36 -040026
Josef Bacik5103e942007-11-16 11:45:54 -050027#include "ctree.h"
Josef Bacik33268ea2008-07-24 12:16:36 -040028#include "btrfs_inode.h"
Josef Bacik5103e942007-11-16 11:45:54 -050029#include "xattr.h"
Josef Bacik33268ea2008-07-24 12:16:36 -040030
Chris Mason0eda2942009-10-13 13:50:18 -040031#ifdef CONFIG_BTRFS_FS_POSIX_ACL
Josef Bacikeab922e2008-08-28 06:21:15 -040032
Josef Bacik33268ea2008-07-24 12:16:36 -040033static struct posix_acl *btrfs_get_acl(struct inode *inode, int type)
34{
Christoph Hellwig95819c02008-08-28 06:21:17 -040035 int size;
36 const char *name;
Josef Bacik33268ea2008-07-24 12:16:36 -040037 char *value = NULL;
Al Viro073aaa12009-06-09 12:11:54 -040038 struct posix_acl *acl;
39
Miao Xied0f69682011-01-25 15:46:17 +080040 if (!IS_POSIXACL(inode))
41 return NULL;
42
Al Viro073aaa12009-06-09 12:11:54 -040043 acl = get_cached_acl(inode, type);
44 if (acl != ACL_NOT_CACHED)
45 return acl;
Josef Bacik33268ea2008-07-24 12:16:36 -040046
47 switch (type) {
48 case ACL_TYPE_ACCESS:
Christoph Hellwig95819c02008-08-28 06:21:17 -040049 name = POSIX_ACL_XATTR_ACCESS;
Josef Bacik33268ea2008-07-24 12:16:36 -040050 break;
51 case ACL_TYPE_DEFAULT:
Christoph Hellwig95819c02008-08-28 06:21:17 -040052 name = POSIX_ACL_XATTR_DEFAULT;
Josef Bacik33268ea2008-07-24 12:16:36 -040053 break;
54 default:
Al Viro073aaa12009-06-09 12:11:54 -040055 BUG();
Josef Bacik33268ea2008-07-24 12:16:36 -040056 }
57
Christoph Hellwig95819c02008-08-28 06:21:17 -040058 size = __btrfs_getxattr(inode, name, "", 0);
Josef Bacik33268ea2008-07-24 12:16:36 -040059 if (size > 0) {
60 value = kzalloc(size, GFP_NOFS);
61 if (!value)
62 return ERR_PTR(-ENOMEM);
Christoph Hellwig95819c02008-08-28 06:21:17 -040063 size = __btrfs_getxattr(inode, name, value, size);
Josef Bacik33268ea2008-07-24 12:16:36 -040064 if (size > 0) {
65 acl = posix_acl_from_xattr(value, size);
Jesper Juhl42838bb2011-01-06 21:45:21 +000066 if (IS_ERR(acl)) {
67 kfree(value);
Dan Carpenter834e7472010-05-29 09:48:35 +000068 return acl;
Jesper Juhl42838bb2011-01-06 21:45:21 +000069 }
Al Viro073aaa12009-06-09 12:11:54 -040070 set_cached_acl(inode, type, acl);
Josef Bacik33268ea2008-07-24 12:16:36 -040071 }
72 kfree(value);
Chris Mason7b1a14b2009-04-27 10:49:53 -040073 } else if (size == -ENOENT || size == -ENODATA || size == 0) {
74 /* FIXME, who returns -ENOENT? I think nobody */
Josef Bacik33268ea2008-07-24 12:16:36 -040075 acl = NULL;
Al Viro073aaa12009-06-09 12:11:54 -040076 set_cached_acl(inode, type, acl);
Chris Mason7b1a14b2009-04-27 10:49:53 -040077 } else {
78 acl = ERR_PTR(-EIO);
Josef Bacik33268ea2008-07-24 12:16:36 -040079 }
80
81 return acl;
82}
83
Christoph Hellwig431547b2009-11-13 09:52:56 +000084static int btrfs_xattr_acl_get(struct dentry *dentry, const char *name,
85 void *value, size_t size, int type)
Josef Bacik33268ea2008-07-24 12:16:36 -040086{
87 struct posix_acl *acl;
88 int ret = 0;
89
Miao Xied0f69682011-01-25 15:46:17 +080090 if (!IS_POSIXACL(dentry->d_inode))
91 return -EOPNOTSUPP;
92
Christoph Hellwig431547b2009-11-13 09:52:56 +000093 acl = btrfs_get_acl(dentry->d_inode, type);
Josef Bacik33268ea2008-07-24 12:16:36 -040094
95 if (IS_ERR(acl))
96 return PTR_ERR(acl);
97 if (acl == NULL)
98 return -ENODATA;
99 ret = posix_acl_to_xattr(acl, value, size);
100 posix_acl_release(acl);
101
102 return ret;
103}
104
105/*
106 * Needs to be called with fs_mutex held
107 */
Yan, Zhengf34f57a2009-11-12 09:35:27 +0000108static int btrfs_set_acl(struct btrfs_trans_handle *trans,
109 struct inode *inode, struct posix_acl *acl, int type)
Josef Bacik33268ea2008-07-24 12:16:36 -0400110{
Christoph Hellwig95819c02008-08-28 06:21:17 -0400111 int ret, size = 0;
112 const char *name;
Josef Bacik33268ea2008-07-24 12:16:36 -0400113 char *value = NULL;
114 mode_t mode;
115
116 if (acl) {
117 ret = posix_acl_valid(acl);
118 if (ret < 0)
119 return ret;
120 ret = 0;
121 }
122
123 switch (type) {
124 case ACL_TYPE_ACCESS:
125 mode = inode->i_mode;
Christoph Hellwig95819c02008-08-28 06:21:17 -0400126 name = POSIX_ACL_XATTR_ACCESS;
Chris Masona9cc71a2010-01-17 20:36:18 -0500127 if (acl) {
128 ret = posix_acl_equiv_mode(acl, &mode);
129 if (ret < 0)
130 return ret;
131 inode->i_mode = mode;
132 }
133 ret = 0;
Josef Bacik33268ea2008-07-24 12:16:36 -0400134 break;
135 case ACL_TYPE_DEFAULT:
136 if (!S_ISDIR(inode->i_mode))
137 return acl ? -EINVAL : 0;
Christoph Hellwig95819c02008-08-28 06:21:17 -0400138 name = POSIX_ACL_XATTR_DEFAULT;
Josef Bacik33268ea2008-07-24 12:16:36 -0400139 break;
140 default:
141 return -EINVAL;
142 }
143
144 if (acl) {
145 size = posix_acl_xattr_size(acl->a_count);
146 value = kmalloc(size, GFP_NOFS);
147 if (!value) {
148 ret = -ENOMEM;
149 goto out;
150 }
151
152 ret = posix_acl_to_xattr(acl, value, size);
153 if (ret < 0)
154 goto out;
155 }
156
Yan, Zhengf34f57a2009-11-12 09:35:27 +0000157 ret = __btrfs_setxattr(trans, inode, name, value, size, 0);
Josef Bacik33268ea2008-07-24 12:16:36 -0400158out:
Chris Masond3977122009-01-05 21:25:51 -0500159 kfree(value);
Josef Bacik33268ea2008-07-24 12:16:36 -0400160
161 if (!ret)
Al Viro073aaa12009-06-09 12:11:54 -0400162 set_cached_acl(inode, type, acl);
Josef Bacik33268ea2008-07-24 12:16:36 -0400163
164 return ret;
165}
Yanfb4bc1e2008-01-17 11:59:51 -0500166
Christoph Hellwig431547b2009-11-13 09:52:56 +0000167static int btrfs_xattr_acl_set(struct dentry *dentry, const char *name,
168 const void *value, size_t size, int flags, int type)
Yan744f52f2008-01-14 13:26:08 -0500169{
Yan, Zhengf34f57a2009-11-12 09:35:27 +0000170 int ret;
Josef Bacik33268ea2008-07-24 12:16:36 -0400171 struct posix_acl *acl = NULL;
Josef Bacik5103e942007-11-16 11:45:54 -0500172
Serge E. Hallyn2e149672011-03-23 16:43:26 -0700173 if (!inode_owner_or_capable(dentry->d_inode))
Shi Weihua2f26afb2010-05-18 00:50:32 +0000174 return -EPERM;
175
Shi Weihua731e3d12010-05-18 00:51:54 +0000176 if (!IS_POSIXACL(dentry->d_inode))
177 return -EOPNOTSUPP;
178
Yan744f52f2008-01-14 13:26:08 -0500179 if (value) {
180 acl = posix_acl_from_xattr(value, size);
181 if (acl == NULL) {
182 value = NULL;
183 size = 0;
184 } else if (IS_ERR(acl)) {
Josef Bacik33268ea2008-07-24 12:16:36 -0400185 return PTR_ERR(acl);
Yan744f52f2008-01-14 13:26:08 -0500186 }
Yan744f52f2008-01-14 13:26:08 -0500187 }
Josef Bacik33268ea2008-07-24 12:16:36 -0400188
Chris Masonebfee3d2009-12-17 15:02:22 -0500189 ret = btrfs_set_acl(NULL, dentry->d_inode, acl, type);
Josef Bacik33268ea2008-07-24 12:16:36 -0400190
191 posix_acl_release(acl);
192
193 return ret;
Yan744f52f2008-01-14 13:26:08 -0500194}
Josef Bacik1caf9342007-11-19 10:18:17 -0500195
Nick Pigginb74c79e2011-01-07 17:49:58 +1100196int btrfs_check_acl(struct inode *inode, int mask, unsigned int flags)
Josef Bacik33268ea2008-07-24 12:16:36 -0400197{
Josef Bacik33268ea2008-07-24 12:16:36 -0400198 int error = -EAGAIN;
199
Nick Piggin258a5aa2011-01-07 17:50:01 +1100200 if (flags & IPERM_FLAG_RCU) {
201 if (!negative_cached_acl(inode, ACL_TYPE_ACCESS))
202 error = -ECHILD;
Josef Bacik33268ea2008-07-24 12:16:36 -0400203
Nick Piggin258a5aa2011-01-07 17:50:01 +1100204 } else {
205 struct posix_acl *acl;
206 acl = btrfs_get_acl(inode, ACL_TYPE_ACCESS);
207 if (IS_ERR(acl))
208 return PTR_ERR(acl);
209 if (acl) {
210 error = posix_acl_permission(inode, acl, mask);
211 posix_acl_release(acl);
212 }
Josef Bacik33268ea2008-07-24 12:16:36 -0400213 }
214
215 return error;
216}
217
218/*
219 * btrfs_init_acl is already generally called under fs_mutex, so the locking
220 * stuff has been fixed to work with that. If the locking stuff changes, we
221 * need to re-evaluate the acl locking stuff.
222 */
Yan, Zhengf34f57a2009-11-12 09:35:27 +0000223int btrfs_init_acl(struct btrfs_trans_handle *trans,
224 struct inode *inode, struct inode *dir)
Josef Bacik33268ea2008-07-24 12:16:36 -0400225{
226 struct posix_acl *acl = NULL;
227 int ret = 0;
228
229 /* this happens with subvols */
230 if (!dir)
231 return 0;
232
233 if (!S_ISLNK(inode->i_mode)) {
234 if (IS_POSIXACL(dir)) {
235 acl = btrfs_get_acl(dir, ACL_TYPE_DEFAULT);
236 if (IS_ERR(acl))
237 return PTR_ERR(acl);
238 }
239
240 if (!acl)
Al Viroce3b0f82009-03-29 19:08:22 -0400241 inode->i_mode &= ~current_umask();
Josef Bacik33268ea2008-07-24 12:16:36 -0400242 }
243
244 if (IS_POSIXACL(dir) && acl) {
245 struct posix_acl *clone;
246 mode_t mode;
247
248 if (S_ISDIR(inode->i_mode)) {
Yan, Zhengf34f57a2009-11-12 09:35:27 +0000249 ret = btrfs_set_acl(trans, inode, acl,
250 ACL_TYPE_DEFAULT);
Josef Bacik33268ea2008-07-24 12:16:36 -0400251 if (ret)
252 goto failed;
253 }
254 clone = posix_acl_clone(acl, GFP_NOFS);
255 ret = -ENOMEM;
256 if (!clone)
257 goto failed;
258
259 mode = inode->i_mode;
260 ret = posix_acl_create_masq(clone, &mode);
261 if (ret >= 0) {
262 inode->i_mode = mode;
263 if (ret > 0) {
264 /* we need an acl */
Yan, Zhengf34f57a2009-11-12 09:35:27 +0000265 ret = btrfs_set_acl(trans, inode, clone,
Josef Bacik33268ea2008-07-24 12:16:36 -0400266 ACL_TYPE_ACCESS);
267 }
268 }
Yang Hongyangf8581532010-01-26 00:48:23 +0000269 posix_acl_release(clone);
Josef Bacik33268ea2008-07-24 12:16:36 -0400270 }
271failed:
272 posix_acl_release(acl);
273
274 return ret;
275}
276
277int btrfs_acl_chmod(struct inode *inode)
278{
279 struct posix_acl *acl, *clone;
280 int ret = 0;
281
282 if (S_ISLNK(inode->i_mode))
283 return -EOPNOTSUPP;
284
285 if (!IS_POSIXACL(inode))
286 return 0;
287
288 acl = btrfs_get_acl(inode, ACL_TYPE_ACCESS);
289 if (IS_ERR(acl) || !acl)
290 return PTR_ERR(acl);
291
292 clone = posix_acl_clone(acl, GFP_KERNEL);
293 posix_acl_release(acl);
294 if (!clone)
295 return -ENOMEM;
296
297 ret = posix_acl_chmod_masq(clone, inode->i_mode);
298 if (!ret)
Yan, Zhengf34f57a2009-11-12 09:35:27 +0000299 ret = btrfs_set_acl(NULL, inode, clone, ACL_TYPE_ACCESS);
Josef Bacik33268ea2008-07-24 12:16:36 -0400300
301 posix_acl_release(clone);
302
303 return ret;
304}
305
Stephen Hemmingerf01cbd32010-05-13 17:53:15 -0700306const struct xattr_handler btrfs_xattr_acl_default_handler = {
Josef Bacik5103e942007-11-16 11:45:54 -0500307 .prefix = POSIX_ACL_XATTR_DEFAULT,
Christoph Hellwig431547b2009-11-13 09:52:56 +0000308 .flags = ACL_TYPE_DEFAULT,
309 .get = btrfs_xattr_acl_get,
310 .set = btrfs_xattr_acl_set,
Josef Bacik5103e942007-11-16 11:45:54 -0500311};
312
Stephen Hemmingerf01cbd32010-05-13 17:53:15 -0700313const struct xattr_handler btrfs_xattr_acl_access_handler = {
Josef Bacik5103e942007-11-16 11:45:54 -0500314 .prefix = POSIX_ACL_XATTR_ACCESS,
Christoph Hellwig431547b2009-11-13 09:52:56 +0000315 .flags = ACL_TYPE_ACCESS,
316 .get = btrfs_xattr_acl_get,
317 .set = btrfs_xattr_acl_set,
Josef Bacik5103e942007-11-16 11:45:54 -0500318};
Josef Bacikeab922e2008-08-28 06:21:15 -0400319
Chris Mason0eda2942009-10-13 13:50:18 -0400320#else /* CONFIG_BTRFS_FS_POSIX_ACL */
Josef Bacikeab922e2008-08-28 06:21:15 -0400321
322int btrfs_acl_chmod(struct inode *inode)
323{
324 return 0;
325}
326
Yan, Zhengf34f57a2009-11-12 09:35:27 +0000327int btrfs_init_acl(struct btrfs_trans_handle *trans,
328 struct inode *inode, struct inode *dir)
Josef Bacikeab922e2008-08-28 06:21:15 -0400329{
330 return 0;
331}
332
Chris Mason0eda2942009-10-13 13:50:18 -0400333#endif /* CONFIG_BTRFS_FS_POSIX_ACL */