blob: a46101ee867afa22e5ee94f8161610433fffc00f [file] [log] [blame]
KaiGai Kohei652ecc22006-05-13 15:18:27 +09001/*
2 * JFFS2 -- Journalling Flash File System, Version 2.
KaiGai Koheiaa98d7c2006-05-13 15:09:47 +09003 *
David Woodhousec00c3102007-04-25 14:16:47 +01004 * Copyright © 2006 NEC Corporation
KaiGai Koheiaa98d7c2006-05-13 15:09:47 +09005 *
KaiGai Kohei652ecc22006-05-13 15:18:27 +09006 * Created by KaiGai Kohei <kaigai@ak.jp.nec.com>
7 *
8 * For licensing information, see the file 'LICENCE' in this directory.
9 *
10 */
David Woodhousec00c3102007-04-25 14:16:47 +010011
KaiGai Koheiaa98d7c2006-05-13 15:09:47 +090012#include <linux/kernel.h>
13#include <linux/slab.h>
14#include <linux/fs.h>
Al Viro914e2632006-10-18 13:55:46 -040015#include <linux/sched.h>
KaiGai Koheiaa98d7c2006-05-13 15:09:47 +090016#include <linux/time.h>
17#include <linux/crc32.h>
18#include <linux/jffs2.h>
19#include <linux/xattr.h>
20#include <linux/posix_acl_xattr.h>
21#include <linux/mtd/mtd.h>
22#include "nodelist.h"
23
24static size_t jffs2_acl_size(int count)
25{
26 if (count <= 4) {
KaiGai Koheide1f72f2006-05-13 15:13:27 +090027 return sizeof(struct jffs2_acl_header)
28 + count * sizeof(struct jffs2_acl_entry_short);
KaiGai Koheiaa98d7c2006-05-13 15:09:47 +090029 } else {
KaiGai Koheide1f72f2006-05-13 15:13:27 +090030 return sizeof(struct jffs2_acl_header)
31 + 4 * sizeof(struct jffs2_acl_entry_short)
32 + (count - 4) * sizeof(struct jffs2_acl_entry);
KaiGai Koheiaa98d7c2006-05-13 15:09:47 +090033 }
34}
35
36static int jffs2_acl_count(size_t size)
37{
38 size_t s;
39
KaiGai Koheide1f72f2006-05-13 15:13:27 +090040 size -= sizeof(struct jffs2_acl_header);
41 s = size - 4 * sizeof(struct jffs2_acl_entry_short);
KaiGai Koheiaa98d7c2006-05-13 15:09:47 +090042 if (s < 0) {
KaiGai Koheide1f72f2006-05-13 15:13:27 +090043 if (size % sizeof(struct jffs2_acl_entry_short))
KaiGai Koheiaa98d7c2006-05-13 15:09:47 +090044 return -1;
KaiGai Koheide1f72f2006-05-13 15:13:27 +090045 return size / sizeof(struct jffs2_acl_entry_short);
KaiGai Koheiaa98d7c2006-05-13 15:09:47 +090046 } else {
KaiGai Koheide1f72f2006-05-13 15:13:27 +090047 if (s % sizeof(struct jffs2_acl_entry))
KaiGai Koheiaa98d7c2006-05-13 15:09:47 +090048 return -1;
KaiGai Koheide1f72f2006-05-13 15:13:27 +090049 return s / sizeof(struct jffs2_acl_entry) + 4;
KaiGai Koheiaa98d7c2006-05-13 15:09:47 +090050 }
51}
52
KaiGai Koheidea80132006-05-13 15:20:24 +090053static struct posix_acl *jffs2_acl_from_medium(void *value, size_t size)
KaiGai Koheiaa98d7c2006-05-13 15:09:47 +090054{
KaiGai Koheidea80132006-05-13 15:20:24 +090055 void *end = value + size;
56 struct jffs2_acl_header *header = value;
57 struct jffs2_acl_entry *entry;
KaiGai Koheiaa98d7c2006-05-13 15:09:47 +090058 struct posix_acl *acl;
59 uint32_t ver;
60 int i, count;
61
62 if (!value)
63 return NULL;
KaiGai Koheide1f72f2006-05-13 15:13:27 +090064 if (size < sizeof(struct jffs2_acl_header))
KaiGai Koheiaa98d7c2006-05-13 15:09:47 +090065 return ERR_PTR(-EINVAL);
KaiGai Koheidea80132006-05-13 15:20:24 +090066 ver = je32_to_cpu(header->a_version);
KaiGai Koheiaa98d7c2006-05-13 15:09:47 +090067 if (ver != JFFS2_ACL_VERSION) {
68 JFFS2_WARNING("Invalid ACL version. (=%u)\n", ver);
69 return ERR_PTR(-EINVAL);
70 }
71
KaiGai Koheidea80132006-05-13 15:20:24 +090072 value += sizeof(struct jffs2_acl_header);
KaiGai Koheiaa98d7c2006-05-13 15:09:47 +090073 count = jffs2_acl_count(size);
74 if (count < 0)
75 return ERR_PTR(-EINVAL);
76 if (count == 0)
77 return NULL;
78
79 acl = posix_acl_alloc(count, GFP_KERNEL);
80 if (!acl)
81 return ERR_PTR(-ENOMEM);
82
83 for (i=0; i < count; i++) {
KaiGai Koheidea80132006-05-13 15:20:24 +090084 entry = value;
85 if (value + sizeof(struct jffs2_acl_entry_short) > end)
KaiGai Koheiaa98d7c2006-05-13 15:09:47 +090086 goto fail;
87 acl->a_entries[i].e_tag = je16_to_cpu(entry->e_tag);
88 acl->a_entries[i].e_perm = je16_to_cpu(entry->e_perm);
89 switch (acl->a_entries[i].e_tag) {
90 case ACL_USER_OBJ:
91 case ACL_GROUP_OBJ:
92 case ACL_MASK:
93 case ACL_OTHER:
KaiGai Koheidea80132006-05-13 15:20:24 +090094 value += sizeof(struct jffs2_acl_entry_short);
KaiGai Koheiaa98d7c2006-05-13 15:09:47 +090095 acl->a_entries[i].e_id = ACL_UNDEFINED_ID;
96 break;
97
98 case ACL_USER:
99 case ACL_GROUP:
KaiGai Koheidea80132006-05-13 15:20:24 +0900100 value += sizeof(struct jffs2_acl_entry);
101 if (value > end)
KaiGai Koheiaa98d7c2006-05-13 15:09:47 +0900102 goto fail;
103 acl->a_entries[i].e_id = je32_to_cpu(entry->e_id);
104 break;
105
106 default:
107 goto fail;
108 }
109 }
110 if (value != end)
111 goto fail;
112 return acl;
113 fail:
114 posix_acl_release(acl);
115 return ERR_PTR(-EINVAL);
116}
117
118static void *jffs2_acl_to_medium(const struct posix_acl *acl, size_t *size)
119{
KaiGai Koheidea80132006-05-13 15:20:24 +0900120 struct jffs2_acl_header *header;
121 struct jffs2_acl_entry *entry;
122 void *e;
KaiGai Koheiaa98d7c2006-05-13 15:09:47 +0900123 size_t i;
124
125 *size = jffs2_acl_size(acl->a_count);
KaiGai Koheidea80132006-05-13 15:20:24 +0900126 header = kmalloc(sizeof(*header) + acl->a_count * sizeof(*entry), GFP_KERNEL);
127 if (!header)
KaiGai Koheiaa98d7c2006-05-13 15:09:47 +0900128 return ERR_PTR(-ENOMEM);
KaiGai Koheidea80132006-05-13 15:20:24 +0900129 header->a_version = cpu_to_je32(JFFS2_ACL_VERSION);
130 e = header + 1;
KaiGai Koheiaa98d7c2006-05-13 15:09:47 +0900131 for (i=0; i < acl->a_count; i++) {
KaiGai Koheidea80132006-05-13 15:20:24 +0900132 entry = e;
KaiGai Koheiaa98d7c2006-05-13 15:09:47 +0900133 entry->e_tag = cpu_to_je16(acl->a_entries[i].e_tag);
134 entry->e_perm = cpu_to_je16(acl->a_entries[i].e_perm);
135 switch(acl->a_entries[i].e_tag) {
136 case ACL_USER:
137 case ACL_GROUP:
138 entry->e_id = cpu_to_je32(acl->a_entries[i].e_id);
KaiGai Koheide1f72f2006-05-13 15:13:27 +0900139 e += sizeof(struct jffs2_acl_entry);
KaiGai Koheiaa98d7c2006-05-13 15:09:47 +0900140 break;
141
142 case ACL_USER_OBJ:
143 case ACL_GROUP_OBJ:
144 case ACL_MASK:
145 case ACL_OTHER:
KaiGai Koheide1f72f2006-05-13 15:13:27 +0900146 e += sizeof(struct jffs2_acl_entry_short);
KaiGai Koheiaa98d7c2006-05-13 15:09:47 +0900147 break;
148
149 default:
150 goto fail;
151 }
152 }
KaiGai Koheidea80132006-05-13 15:20:24 +0900153 return header;
KaiGai Koheiaa98d7c2006-05-13 15:09:47 +0900154 fail:
KaiGai Koheidea80132006-05-13 15:20:24 +0900155 kfree(header);
KaiGai Koheiaa98d7c2006-05-13 15:09:47 +0900156 return ERR_PTR(-EINVAL);
157}
158
159static struct posix_acl *jffs2_iget_acl(struct inode *inode, struct posix_acl **i_acl)
160{
161 struct posix_acl *acl = JFFS2_ACL_NOT_CACHED;
162
163 spin_lock(&inode->i_lock);
164 if (*i_acl != JFFS2_ACL_NOT_CACHED)
165 acl = posix_acl_dup(*i_acl);
166 spin_unlock(&inode->i_lock);
167 return acl;
168}
169
170static void jffs2_iset_acl(struct inode *inode, struct posix_acl **i_acl, struct posix_acl *acl)
171{
172 spin_lock(&inode->i_lock);
173 if (*i_acl != JFFS2_ACL_NOT_CACHED)
174 posix_acl_release(*i_acl);
175 *i_acl = posix_acl_dup(acl);
176 spin_unlock(&inode->i_lock);
177}
178
179static struct posix_acl *jffs2_get_acl(struct inode *inode, int type)
180{
181 struct jffs2_inode_info *f = JFFS2_INODE_INFO(inode);
182 struct posix_acl *acl;
183 char *value = NULL;
184 int rc, xprefix;
185
186 switch (type) {
187 case ACL_TYPE_ACCESS:
188 acl = jffs2_iget_acl(inode, &f->i_acl_access);
189 if (acl != JFFS2_ACL_NOT_CACHED)
190 return acl;
191 xprefix = JFFS2_XPREFIX_ACL_ACCESS;
192 break;
193 case ACL_TYPE_DEFAULT:
194 acl = jffs2_iget_acl(inode, &f->i_acl_default);
195 if (acl != JFFS2_ACL_NOT_CACHED)
196 return acl;
197 xprefix = JFFS2_XPREFIX_ACL_DEFAULT;
198 break;
199 default:
200 return ERR_PTR(-EINVAL);
201 }
202 rc = do_jffs2_getxattr(inode, xprefix, "", NULL, 0);
203 if (rc > 0) {
204 value = kmalloc(rc, GFP_KERNEL);
205 if (!value)
206 return ERR_PTR(-ENOMEM);
207 rc = do_jffs2_getxattr(inode, xprefix, "", value, rc);
208 }
209 if (rc > 0) {
210 acl = jffs2_acl_from_medium(value, rc);
211 } else if (rc == -ENODATA || rc == -ENOSYS) {
212 acl = NULL;
213 } else {
214 acl = ERR_PTR(rc);
215 }
216 if (value)
217 kfree(value);
218 if (!IS_ERR(acl)) {
219 switch (type) {
220 case ACL_TYPE_ACCESS:
221 jffs2_iset_acl(inode, &f->i_acl_access, acl);
222 break;
223 case ACL_TYPE_DEFAULT:
224 jffs2_iset_acl(inode, &f->i_acl_default, acl);
225 break;
226 }
227 }
228 return acl;
229}
230
231static int jffs2_set_acl(struct inode *inode, int type, struct posix_acl *acl)
232{
233 struct jffs2_inode_info *f = JFFS2_INODE_INFO(inode);
234 size_t size = 0;
235 char *value = NULL;
236 int rc, xprefix;
237
238 if (S_ISLNK(inode->i_mode))
239 return -EOPNOTSUPP;
240
241 switch (type) {
242 case ACL_TYPE_ACCESS:
243 xprefix = JFFS2_XPREFIX_ACL_ACCESS;
244 if (acl) {
245 mode_t mode = inode->i_mode;
246 rc = posix_acl_equiv_mode(acl, &mode);
247 if (rc < 0)
248 return rc;
249 if (inode->i_mode != mode) {
250 inode->i_mode = mode;
251 jffs2_dirty_inode(inode);
252 }
253 if (rc == 0)
254 acl = NULL;
255 }
256 break;
257 case ACL_TYPE_DEFAULT:
258 xprefix = JFFS2_XPREFIX_ACL_DEFAULT;
259 if (!S_ISDIR(inode->i_mode))
260 return acl ? -EACCES : 0;
261 break;
262 default:
263 return -EINVAL;
264 }
265 if (acl) {
266 value = jffs2_acl_to_medium(acl, &size);
267 if (IS_ERR(value))
268 return PTR_ERR(value);
269 }
270
271 rc = do_jffs2_setxattr(inode, xprefix, "", value, size, 0);
KaiGai Koheia1ae76e2006-06-11 10:45:22 +0900272 if (!value && rc == -ENODATA)
273 rc = 0;
KaiGai Koheiaa98d7c2006-05-13 15:09:47 +0900274 if (value)
275 kfree(value);
276 if (!rc) {
277 switch(type) {
278 case ACL_TYPE_ACCESS:
279 jffs2_iset_acl(inode, &f->i_acl_access, acl);
280 break;
281 case ACL_TYPE_DEFAULT:
282 jffs2_iset_acl(inode, &f->i_acl_default, acl);
283 break;
284 }
285 }
286 return rc;
287}
288
289static int jffs2_check_acl(struct inode *inode, int mask)
290{
291 struct posix_acl *acl;
292 int rc;
293
294 acl = jffs2_get_acl(inode, ACL_TYPE_ACCESS);
295 if (IS_ERR(acl))
296 return PTR_ERR(acl);
297 if (acl) {
298 rc = posix_acl_permission(inode, acl, mask);
299 posix_acl_release(acl);
300 return rc;
301 }
302 return -EAGAIN;
303}
304
305int jffs2_permission(struct inode *inode, int mask, struct nameidata *nd)
306{
307 return generic_permission(inode, mask, jffs2_check_acl);
308}
309
310int jffs2_init_acl(struct inode *inode, struct inode *dir)
311{
312 struct jffs2_inode_info *f = JFFS2_INODE_INFO(inode);
313 struct posix_acl *acl = NULL, *clone;
314 mode_t mode;
315 int rc = 0;
316
317 f->i_acl_access = JFFS2_ACL_NOT_CACHED;
318 f->i_acl_default = JFFS2_ACL_NOT_CACHED;
319 if (!S_ISLNK(inode->i_mode)) {
320 acl = jffs2_get_acl(dir, ACL_TYPE_DEFAULT);
321 if (IS_ERR(acl))
322 return PTR_ERR(acl);
323 if (!acl)
324 inode->i_mode &= ~current->fs->umask;
325 }
326 if (acl) {
327 if (S_ISDIR(inode->i_mode)) {
328 rc = jffs2_set_acl(inode, ACL_TYPE_DEFAULT, acl);
329 if (rc)
330 goto cleanup;
331 }
332 clone = posix_acl_clone(acl, GFP_KERNEL);
333 rc = -ENOMEM;
334 if (!clone)
335 goto cleanup;
336 mode = inode->i_mode;
337 rc = posix_acl_create_masq(clone, &mode);
338 if (rc >= 0) {
339 inode->i_mode = mode;
340 if (rc > 0)
341 rc = jffs2_set_acl(inode, ACL_TYPE_ACCESS, clone);
342 }
343 posix_acl_release(clone);
344 }
345 cleanup:
346 posix_acl_release(acl);
347 return rc;
348}
349
KaiGai Koheic7afb0f2006-07-02 15:13:46 +0100350void jffs2_clear_acl(struct jffs2_inode_info *f)
KaiGai Koheiaa98d7c2006-05-13 15:09:47 +0900351{
KaiGai Koheiaa98d7c2006-05-13 15:09:47 +0900352 if (f->i_acl_access && f->i_acl_access != JFFS2_ACL_NOT_CACHED) {
353 posix_acl_release(f->i_acl_access);
354 f->i_acl_access = JFFS2_ACL_NOT_CACHED;
355 }
356 if (f->i_acl_default && f->i_acl_default != JFFS2_ACL_NOT_CACHED) {
357 posix_acl_release(f->i_acl_default);
358 f->i_acl_default = JFFS2_ACL_NOT_CACHED;
359 }
360}
361
362int jffs2_acl_chmod(struct inode *inode)
363{
364 struct posix_acl *acl, *clone;
365 int rc;
366
367 if (S_ISLNK(inode->i_mode))
368 return -EOPNOTSUPP;
369 acl = jffs2_get_acl(inode, ACL_TYPE_ACCESS);
370 if (IS_ERR(acl) || !acl)
371 return PTR_ERR(acl);
372 clone = posix_acl_clone(acl, GFP_KERNEL);
373 posix_acl_release(acl);
374 if (!clone)
375 return -ENOMEM;
376 rc = posix_acl_chmod_masq(clone, inode->i_mode);
377 if (!rc)
378 rc = jffs2_set_acl(inode, ACL_TYPE_ACCESS, clone);
379 posix_acl_release(clone);
380 return rc;
381}
382
383static size_t jffs2_acl_access_listxattr(struct inode *inode, char *list, size_t list_size,
384 const char *name, size_t name_len)
385{
386 const int retlen = sizeof(POSIX_ACL_XATTR_ACCESS);
387
388 if (list && retlen <= list_size)
389 strcpy(list, POSIX_ACL_XATTR_ACCESS);
390 return retlen;
391}
392
393static size_t jffs2_acl_default_listxattr(struct inode *inode, char *list, size_t list_size,
394 const char *name, size_t name_len)
395{
396 const int retlen = sizeof(POSIX_ACL_XATTR_DEFAULT);
397
398 if (list && retlen <= list_size)
399 strcpy(list, POSIX_ACL_XATTR_DEFAULT);
400 return retlen;
401}
402
403static int jffs2_acl_getxattr(struct inode *inode, int type, void *buffer, size_t size)
404{
405 struct posix_acl *acl;
406 int rc;
407
408 acl = jffs2_get_acl(inode, type);
409 if (IS_ERR(acl))
410 return PTR_ERR(acl);
411 if (!acl)
412 return -ENODATA;
413 rc = posix_acl_to_xattr(acl, buffer, size);
414 posix_acl_release(acl);
415
416 return rc;
417}
418
419static int jffs2_acl_access_getxattr(struct inode *inode, const char *name, void *buffer, size_t size)
420{
421 if (name[0] != '\0')
422 return -EINVAL;
423 return jffs2_acl_getxattr(inode, ACL_TYPE_ACCESS, buffer, size);
424}
425
426static int jffs2_acl_default_getxattr(struct inode *inode, const char *name, void *buffer, size_t size)
427{
428 if (name[0] != '\0')
429 return -EINVAL;
430 return jffs2_acl_getxattr(inode, ACL_TYPE_DEFAULT, buffer, size);
431}
432
433static int jffs2_acl_setxattr(struct inode *inode, int type, const void *value, size_t size)
434{
435 struct posix_acl *acl;
436 int rc;
437
438 if ((current->fsuid != inode->i_uid) && !capable(CAP_FOWNER))
439 return -EPERM;
440
441 if (value) {
442 acl = posix_acl_from_xattr(value, size);
443 if (IS_ERR(acl))
444 return PTR_ERR(acl);
445 if (acl) {
446 rc = posix_acl_valid(acl);
447 if (rc)
448 goto out;
449 }
450 } else {
451 acl = NULL;
452 }
453 rc = jffs2_set_acl(inode, type, acl);
454 out:
455 posix_acl_release(acl);
456 return rc;
457}
458
459static int jffs2_acl_access_setxattr(struct inode *inode, const char *name,
460 const void *buffer, size_t size, int flags)
461{
462 if (name[0] != '\0')
463 return -EINVAL;
464 return jffs2_acl_setxattr(inode, ACL_TYPE_ACCESS, buffer, size);
465}
466
467static int jffs2_acl_default_setxattr(struct inode *inode, const char *name,
468 const void *buffer, size_t size, int flags)
469{
470 if (name[0] != '\0')
471 return -EINVAL;
472 return jffs2_acl_setxattr(inode, ACL_TYPE_DEFAULT, buffer, size);
473}
474
475struct xattr_handler jffs2_acl_access_xattr_handler = {
476 .prefix = POSIX_ACL_XATTR_ACCESS,
477 .list = jffs2_acl_access_listxattr,
478 .get = jffs2_acl_access_getxattr,
479 .set = jffs2_acl_access_setxattr,
480};
481
482struct xattr_handler jffs2_acl_default_xattr_handler = {
483 .prefix = POSIX_ACL_XATTR_DEFAULT,
484 .list = jffs2_acl_default_listxattr,
485 .get = jffs2_acl_default_getxattr,
486 .set = jffs2_acl_default_setxattr,
487};