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19#include <linux/fs.h>
20#include <linux/string.h>
21#include <linux/xattr.h>
22#include <linux/posix_acl_xattr.h>
23#include <linux/posix_acl.h>
24#include <linux/sched.h>
25
26#include "ctree.h"
27#include "btrfs_inode.h"
28#include "xattr.h"
29
30#ifdef CONFIG_BTRFS_FS_POSIX_ACL
31
32static struct posix_acl *btrfs_get_acl(struct inode *inode, int type)
33{
34 int size;
35 const char *name;
36 char *value = NULL;
37 struct posix_acl *acl;
38
39 acl = get_cached_acl(inode, type);
40 if (acl != ACL_NOT_CACHED)
41 return acl;
42
43 switch (type) {
44 case ACL_TYPE_ACCESS:
45 name = POSIX_ACL_XATTR_ACCESS;
46 break;
47 case ACL_TYPE_DEFAULT:
48 name = POSIX_ACL_XATTR_DEFAULT;
49 break;
50 default:
51 BUG();
52 }
53
54 size = __btrfs_getxattr(inode, name, "", 0);
55 if (size > 0) {
56 value = kzalloc(size, GFP_NOFS);
57 if (!value)
58 return ERR_PTR(-ENOMEM);
59 size = __btrfs_getxattr(inode, name, value, size);
60 if (size > 0) {
61 acl = posix_acl_from_xattr(value, size);
62 set_cached_acl(inode, type, acl);
63 }
64 kfree(value);
65 } else if (size == -ENOENT || size == -ENODATA || size == 0) {
66
67 acl = NULL;
68 set_cached_acl(inode, type, acl);
69 } else {
70 acl = ERR_PTR(-EIO);
71 }
72
73 return acl;
74}
75
76static int btrfs_xattr_get_acl(struct inode *inode, int type,
77 void *value, size_t size)
78{
79 struct posix_acl *acl;
80 int ret = 0;
81
82 acl = btrfs_get_acl(inode, type);
83
84 if (IS_ERR(acl))
85 return PTR_ERR(acl);
86 if (acl == NULL)
87 return -ENODATA;
88 ret = posix_acl_to_xattr(acl, value, size);
89 posix_acl_release(acl);
90
91 return ret;
92}
93
94
95
96
97static int btrfs_set_acl(struct inode *inode, struct posix_acl *acl, int type)
98{
99 int ret, size = 0;
100 const char *name;
101 char *value = NULL;
102 mode_t mode;
103
104 if (acl) {
105 ret = posix_acl_valid(acl);
106 if (ret < 0)
107 return ret;
108 ret = 0;
109 }
110
111 switch (type) {
112 case ACL_TYPE_ACCESS:
113 mode = inode->i_mode;
114 ret = posix_acl_equiv_mode(acl, &mode);
115 if (ret < 0)
116 return ret;
117 ret = 0;
118 inode->i_mode = mode;
119 name = POSIX_ACL_XATTR_ACCESS;
120 break;
121 case ACL_TYPE_DEFAULT:
122 if (!S_ISDIR(inode->i_mode))
123 return acl ? -EINVAL : 0;
124 name = POSIX_ACL_XATTR_DEFAULT;
125 break;
126 default:
127 return -EINVAL;
128 }
129
130 if (acl) {
131 size = posix_acl_xattr_size(acl->a_count);
132 value = kmalloc(size, GFP_NOFS);
133 if (!value) {
134 ret = -ENOMEM;
135 goto out;
136 }
137
138 ret = posix_acl_to_xattr(acl, value, size);
139 if (ret < 0)
140 goto out;
141 }
142
143 ret = __btrfs_setxattr(inode, name, value, size, 0);
144
145out:
146 kfree(value);
147
148 if (!ret)
149 set_cached_acl(inode, type, acl);
150
151 return ret;
152}
153
154static int btrfs_xattr_set_acl(struct inode *inode, int type,
155 const void *value, size_t size)
156{
157 int ret = 0;
158 struct posix_acl *acl = NULL;
159
160 if (value) {
161 acl = posix_acl_from_xattr(value, size);
162 if (acl == NULL) {
163 value = NULL;
164 size = 0;
165 } else if (IS_ERR(acl)) {
166 return PTR_ERR(acl);
167 }
168 }
169
170 ret = btrfs_set_acl(inode, acl, type);
171
172 posix_acl_release(acl);
173
174 return ret;
175}
176
177
178static int btrfs_xattr_acl_access_get(struct inode *inode, const char *name,
179 void *value, size_t size)
180{
181 return btrfs_xattr_get_acl(inode, ACL_TYPE_ACCESS, value, size);
182}
183
184static int btrfs_xattr_acl_access_set(struct inode *inode, const char *name,
185 const void *value, size_t size, int flags)
186{
187 return btrfs_xattr_set_acl(inode, ACL_TYPE_ACCESS, value, size);
188}
189
190static int btrfs_xattr_acl_default_get(struct inode *inode, const char *name,
191 void *value, size_t size)
192{
193 return btrfs_xattr_get_acl(inode, ACL_TYPE_DEFAULT, value, size);
194}
195
196static int btrfs_xattr_acl_default_set(struct inode *inode, const char *name,
197 const void *value, size_t size, int flags)
198{
199 return btrfs_xattr_set_acl(inode, ACL_TYPE_DEFAULT, value, size);
200}
201
202int btrfs_check_acl(struct inode *inode, int mask)
203{
204 struct posix_acl *acl;
205 int error = -EAGAIN;
206
207 acl = btrfs_get_acl(inode, ACL_TYPE_ACCESS);
208
209 if (IS_ERR(acl))
210 return PTR_ERR(acl);
211 if (acl) {
212 error = posix_acl_permission(inode, acl, mask);
213 posix_acl_release(acl);
214 }
215
216 return error;
217}
218
219
220
221
222
223
224int btrfs_init_acl(struct inode *inode, struct inode *dir)
225{
226 struct posix_acl *acl = NULL;
227 int ret = 0;
228
229
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)
241 inode->i_mode &= ~current_umask();
242 }
243
244 if (IS_POSIXACL(dir) && acl) {
245 struct posix_acl *clone;
246 mode_t mode;
247
248 if (S_ISDIR(inode->i_mode)) {
249 ret = btrfs_set_acl(inode, acl, ACL_TYPE_DEFAULT);
250 if (ret)
251 goto failed;
252 }
253 clone = posix_acl_clone(acl, GFP_NOFS);
254 ret = -ENOMEM;
255 if (!clone)
256 goto failed;
257
258 mode = inode->i_mode;
259 ret = posix_acl_create_masq(clone, &mode);
260 if (ret >= 0) {
261 inode->i_mode = mode;
262 if (ret > 0) {
263
264 ret = btrfs_set_acl(inode, clone,
265 ACL_TYPE_ACCESS);
266 }
267 }
268 }
269failed:
270 posix_acl_release(acl);
271
272 return ret;
273}
274
275int btrfs_acl_chmod(struct inode *inode)
276{
277 struct posix_acl *acl, *clone;
278 int ret = 0;
279
280 if (S_ISLNK(inode->i_mode))
281 return -EOPNOTSUPP;
282
283 if (!IS_POSIXACL(inode))
284 return 0;
285
286 acl = btrfs_get_acl(inode, ACL_TYPE_ACCESS);
287 if (IS_ERR(acl) || !acl)
288 return PTR_ERR(acl);
289
290 clone = posix_acl_clone(acl, GFP_KERNEL);
291 posix_acl_release(acl);
292 if (!clone)
293 return -ENOMEM;
294
295 ret = posix_acl_chmod_masq(clone, inode->i_mode);
296 if (!ret)
297 ret = btrfs_set_acl(inode, clone, ACL_TYPE_ACCESS);
298
299 posix_acl_release(clone);
300
301 return ret;
302}
303
304struct xattr_handler btrfs_xattr_acl_default_handler = {
305 .prefix = POSIX_ACL_XATTR_DEFAULT,
306 .get = btrfs_xattr_acl_default_get,
307 .set = btrfs_xattr_acl_default_set,
308};
309
310struct xattr_handler btrfs_xattr_acl_access_handler = {
311 .prefix = POSIX_ACL_XATTR_ACCESS,
312 .get = btrfs_xattr_acl_access_get,
313 .set = btrfs_xattr_acl_access_set,
314};
315
316#else
317
318int btrfs_acl_chmod(struct inode *inode)
319{
320 return 0;
321}
322
323int btrfs_init_acl(struct inode *inode, struct inode *dir)
324{
325 return 0;
326}
327
328#endif
329
