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0a8165d7 1/*
af48b85b
JK
2 * fs/f2fs/xattr.c
3 *
4 * Copyright (c) 2012 Samsung Electronics Co., Ltd.
5 * http://www.samsung.com/
6 *
7 * Portions of this code from linux/fs/ext2/xattr.c
8 *
9 * Copyright (C) 2001-2003 Andreas Gruenbacher <agruen@suse.de>
10 *
11 * Fix by Harrison Xing <harrison@mountainviewdata.com>.
12 * Extended attributes for symlinks and special files added per
13 * suggestion of Luka Renko <luka.renko@hermes.si>.
14 * xattr consolidation Copyright (c) 2004 James Morris <jmorris@redhat.com>,
15 * Red Hat Inc.
16 *
17 * This program is free software; you can redistribute it and/or modify
18 * it under the terms of the GNU General Public License version 2 as
19 * published by the Free Software Foundation.
20 */
21#include <linux/rwsem.h>
22#include <linux/f2fs_fs.h>
8ae8f162 23#include <linux/security.h>
a6dda0e6 24#include <linux/posix_acl_xattr.h>
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25#include "f2fs.h"
26#include "xattr.h"
27
28static size_t f2fs_xattr_generic_list(struct dentry *dentry, char *list,
29 size_t list_size, const char *name, size_t name_len, int type)
30{
31 struct f2fs_sb_info *sbi = F2FS_SB(dentry->d_sb);
32 int total_len, prefix_len = 0;
33 const char *prefix = NULL;
34
35 switch (type) {
36 case F2FS_XATTR_INDEX_USER:
37 if (!test_opt(sbi, XATTR_USER))
38 return -EOPNOTSUPP;
39 prefix = XATTR_USER_PREFIX;
40 prefix_len = XATTR_USER_PREFIX_LEN;
41 break;
42 case F2FS_XATTR_INDEX_TRUSTED:
43 if (!capable(CAP_SYS_ADMIN))
44 return -EPERM;
45 prefix = XATTR_TRUSTED_PREFIX;
46 prefix_len = XATTR_TRUSTED_PREFIX_LEN;
47 break;
8ae8f162
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48 case F2FS_XATTR_INDEX_SECURITY:
49 prefix = XATTR_SECURITY_PREFIX;
50 prefix_len = XATTR_SECURITY_PREFIX_LEN;
51 break;
af48b85b
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52 default:
53 return -EINVAL;
54 }
55
56 total_len = prefix_len + name_len + 1;
57 if (list && total_len <= list_size) {
58 memcpy(list, prefix, prefix_len);
8ae8f162 59 memcpy(list + prefix_len, name, name_len);
af48b85b
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60 list[prefix_len + name_len] = '\0';
61 }
62 return total_len;
63}
64
65static int f2fs_xattr_generic_get(struct dentry *dentry, const char *name,
66 void *buffer, size_t size, int type)
67{
68 struct f2fs_sb_info *sbi = F2FS_SB(dentry->d_sb);
69
70 switch (type) {
71 case F2FS_XATTR_INDEX_USER:
72 if (!test_opt(sbi, XATTR_USER))
73 return -EOPNOTSUPP;
74 break;
75 case F2FS_XATTR_INDEX_TRUSTED:
76 if (!capable(CAP_SYS_ADMIN))
77 return -EPERM;
78 break;
8ae8f162
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79 case F2FS_XATTR_INDEX_SECURITY:
80 break;
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81 default:
82 return -EINVAL;
83 }
84 if (strcmp(name, "") == 0)
85 return -EINVAL;
8ae8f162 86 return f2fs_getxattr(dentry->d_inode, type, name, buffer, size);
af48b85b
JK
87}
88
89static int f2fs_xattr_generic_set(struct dentry *dentry, const char *name,
90 const void *value, size_t size, int flags, int type)
91{
92 struct f2fs_sb_info *sbi = F2FS_SB(dentry->d_sb);
93
94 switch (type) {
95 case F2FS_XATTR_INDEX_USER:
96 if (!test_opt(sbi, XATTR_USER))
97 return -EOPNOTSUPP;
98 break;
99 case F2FS_XATTR_INDEX_TRUSTED:
100 if (!capable(CAP_SYS_ADMIN))
101 return -EPERM;
102 break;
8ae8f162
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103 case F2FS_XATTR_INDEX_SECURITY:
104 break;
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105 default:
106 return -EINVAL;
107 }
108 if (strcmp(name, "") == 0)
109 return -EINVAL;
110
8ae8f162 111 return f2fs_setxattr(dentry->d_inode, type, name, value, size, NULL);
af48b85b
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112}
113
573ea5fc
JK
114static size_t f2fs_xattr_advise_list(struct dentry *dentry, char *list,
115 size_t list_size, const char *name, size_t name_len, int type)
116{
117 const char *xname = F2FS_SYSTEM_ADVISE_PREFIX;
118 size_t size;
119
120 if (type != F2FS_XATTR_INDEX_ADVISE)
121 return 0;
122
123 size = strlen(xname) + 1;
124 if (list && size <= list_size)
125 memcpy(list, xname, size);
126 return size;
127}
128
129static int f2fs_xattr_advise_get(struct dentry *dentry, const char *name,
130 void *buffer, size_t size, int type)
131{
132 struct inode *inode = dentry->d_inode;
133
134 if (strcmp(name, "") != 0)
135 return -EINVAL;
136
137 *((char *)buffer) = F2FS_I(inode)->i_advise;
138 return sizeof(char);
139}
140
141static int f2fs_xattr_advise_set(struct dentry *dentry, const char *name,
142 const void *value, size_t size, int flags, int type)
143{
144 struct inode *inode = dentry->d_inode;
145
146 if (strcmp(name, "") != 0)
147 return -EINVAL;
148 if (!inode_owner_or_capable(inode))
149 return -EPERM;
150 if (value == NULL)
151 return -EINVAL;
152
153 F2FS_I(inode)->i_advise |= *(char *)value;
154 return 0;
155}
156
8ae8f162 157#ifdef CONFIG_F2FS_FS_SECURITY
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RK
158static int __f2fs_setxattr(struct inode *inode, int name_index,
159 const char *name, const void *value, size_t value_len,
160 struct page *ipage);
8ae8f162
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161static int f2fs_initxattrs(struct inode *inode, const struct xattr *xattr_array,
162 void *page)
163{
164 const struct xattr *xattr;
165 int err = 0;
166
167 for (xattr = xattr_array; xattr->name != NULL; xattr++) {
52ab9560 168 err = __f2fs_setxattr(inode, F2FS_XATTR_INDEX_SECURITY,
8ae8f162
JK
169 xattr->name, xattr->value,
170 xattr->value_len, (struct page *)page);
171 if (err < 0)
172 break;
173 }
174 return err;
175}
176
177int f2fs_init_security(struct inode *inode, struct inode *dir,
178 const struct qstr *qstr, struct page *ipage)
179{
180 return security_inode_init_security(inode, dir, qstr,
181 &f2fs_initxattrs, ipage);
182}
183#endif
184
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185const struct xattr_handler f2fs_xattr_user_handler = {
186 .prefix = XATTR_USER_PREFIX,
187 .flags = F2FS_XATTR_INDEX_USER,
188 .list = f2fs_xattr_generic_list,
189 .get = f2fs_xattr_generic_get,
190 .set = f2fs_xattr_generic_set,
191};
192
193const struct xattr_handler f2fs_xattr_trusted_handler = {
194 .prefix = XATTR_TRUSTED_PREFIX,
195 .flags = F2FS_XATTR_INDEX_TRUSTED,
196 .list = f2fs_xattr_generic_list,
197 .get = f2fs_xattr_generic_get,
198 .set = f2fs_xattr_generic_set,
199};
200
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201const struct xattr_handler f2fs_xattr_advise_handler = {
202 .prefix = F2FS_SYSTEM_ADVISE_PREFIX,
203 .flags = F2FS_XATTR_INDEX_ADVISE,
204 .list = f2fs_xattr_advise_list,
205 .get = f2fs_xattr_advise_get,
206 .set = f2fs_xattr_advise_set,
207};
208
8ae8f162
JK
209const struct xattr_handler f2fs_xattr_security_handler = {
210 .prefix = XATTR_SECURITY_PREFIX,
211 .flags = F2FS_XATTR_INDEX_SECURITY,
212 .list = f2fs_xattr_generic_list,
213 .get = f2fs_xattr_generic_get,
214 .set = f2fs_xattr_generic_set,
215};
216
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217static const struct xattr_handler *f2fs_xattr_handler_map[] = {
218 [F2FS_XATTR_INDEX_USER] = &f2fs_xattr_user_handler,
219#ifdef CONFIG_F2FS_FS_POSIX_ACL
a6dda0e6
CH
220 [F2FS_XATTR_INDEX_POSIX_ACL_ACCESS] = &posix_acl_access_xattr_handler,
221 [F2FS_XATTR_INDEX_POSIX_ACL_DEFAULT] = &posix_acl_default_xattr_handler,
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222#endif
223 [F2FS_XATTR_INDEX_TRUSTED] = &f2fs_xattr_trusted_handler,
8ae8f162
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224#ifdef CONFIG_F2FS_FS_SECURITY
225 [F2FS_XATTR_INDEX_SECURITY] = &f2fs_xattr_security_handler,
226#endif
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227 [F2FS_XATTR_INDEX_ADVISE] = &f2fs_xattr_advise_handler,
228};
229
230const struct xattr_handler *f2fs_xattr_handlers[] = {
231 &f2fs_xattr_user_handler,
232#ifdef CONFIG_F2FS_FS_POSIX_ACL
a6dda0e6
CH
233 &posix_acl_access_xattr_handler,
234 &posix_acl_default_xattr_handler,
af48b85b
JK
235#endif
236 &f2fs_xattr_trusted_handler,
8ae8f162
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237#ifdef CONFIG_F2FS_FS_SECURITY
238 &f2fs_xattr_security_handler,
239#endif
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240 &f2fs_xattr_advise_handler,
241 NULL,
242};
243
244static inline const struct xattr_handler *f2fs_xattr_handler(int name_index)
245{
246 const struct xattr_handler *handler = NULL;
247
248 if (name_index > 0 && name_index < ARRAY_SIZE(f2fs_xattr_handler_map))
249 handler = f2fs_xattr_handler_map[name_index];
250 return handler;
251}
252
dd9cfe23
JK
253static struct f2fs_xattr_entry *__find_xattr(void *base_addr, int name_index,
254 size_t name_len, const char *name)
255{
256 struct f2fs_xattr_entry *entry;
257
258 list_for_each_xattr(entry, base_addr) {
259 if (entry->e_name_index != name_index)
260 continue;
261 if (entry->e_name_len != name_len)
262 continue;
263 if (!memcmp(entry->e_name, name, name_len))
264 break;
265 }
266 return entry;
267}
268
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JK
269static void *read_all_xattrs(struct inode *inode, struct page *ipage)
270{
271 struct f2fs_sb_info *sbi = F2FS_SB(inode->i_sb);
272 struct f2fs_xattr_header *header;
273 size_t size = PAGE_SIZE, inline_size = 0;
274 void *txattr_addr;
275
276 inline_size = inline_xattr_size(inode);
277
278 txattr_addr = kzalloc(inline_size + size, GFP_KERNEL);
279 if (!txattr_addr)
280 return NULL;
281
282 /* read from inline xattr */
283 if (inline_size) {
284 struct page *page = NULL;
285 void *inline_addr;
286
287 if (ipage) {
288 inline_addr = inline_xattr_addr(ipage);
289 } else {
290 page = get_node_page(sbi, inode->i_ino);
291 if (IS_ERR(page))
292 goto fail;
293 inline_addr = inline_xattr_addr(page);
294 }
295 memcpy(txattr_addr, inline_addr, inline_size);
296 f2fs_put_page(page, 1);
297 }
298
299 /* read from xattr node block */
300 if (F2FS_I(inode)->i_xattr_nid) {
301 struct page *xpage;
302 void *xattr_addr;
303
304 /* The inode already has an extended attribute block. */
305 xpage = get_node_page(sbi, F2FS_I(inode)->i_xattr_nid);
306 if (IS_ERR(xpage))
307 goto fail;
308
309 xattr_addr = page_address(xpage);
310 memcpy(txattr_addr + inline_size, xattr_addr, PAGE_SIZE);
311 f2fs_put_page(xpage, 1);
312 }
313
314 header = XATTR_HDR(txattr_addr);
315
316 /* never been allocated xattrs */
317 if (le32_to_cpu(header->h_magic) != F2FS_XATTR_MAGIC) {
318 header->h_magic = cpu_to_le32(F2FS_XATTR_MAGIC);
319 header->h_refcount = cpu_to_le32(1);
320 }
321 return txattr_addr;
322fail:
323 kzfree(txattr_addr);
324 return NULL;
325}
326
327static inline int write_all_xattrs(struct inode *inode, __u32 hsize,
328 void *txattr_addr, struct page *ipage)
329{
330 struct f2fs_sb_info *sbi = F2FS_SB(inode->i_sb);
331 size_t inline_size = 0;
332 void *xattr_addr;
333 struct page *xpage;
334 nid_t new_nid = 0;
335 int err;
336
337 inline_size = inline_xattr_size(inode);
338
339 if (hsize > inline_size && !F2FS_I(inode)->i_xattr_nid)
340 if (!alloc_nid(sbi, &new_nid))
341 return -ENOSPC;
342
343 /* write to inline xattr */
344 if (inline_size) {
345 struct page *page = NULL;
346 void *inline_addr;
347
348 if (ipage) {
349 inline_addr = inline_xattr_addr(ipage);
350 } else {
351 page = get_node_page(sbi, inode->i_ino);
352 if (IS_ERR(page)) {
353 alloc_nid_failed(sbi, new_nid);
354 return PTR_ERR(page);
355 }
356 inline_addr = inline_xattr_addr(page);
357 }
358 memcpy(inline_addr, txattr_addr, inline_size);
359 f2fs_put_page(page, 1);
360
361 /* no need to use xattr node block */
362 if (hsize <= inline_size) {
363 err = truncate_xattr_node(inode, ipage);
364 alloc_nid_failed(sbi, new_nid);
365 return err;
366 }
367 }
368
369 /* write to xattr node block */
370 if (F2FS_I(inode)->i_xattr_nid) {
371 xpage = get_node_page(sbi, F2FS_I(inode)->i_xattr_nid);
372 if (IS_ERR(xpage)) {
373 alloc_nid_failed(sbi, new_nid);
374 return PTR_ERR(xpage);
375 }
5d56b671 376 f2fs_bug_on(new_nid);
65985d93
JK
377 } else {
378 struct dnode_of_data dn;
379 set_new_dnode(&dn, inode, NULL, NULL, new_nid);
380 xpage = new_node_page(&dn, XATTR_NODE_OFFSET, ipage);
381 if (IS_ERR(xpage)) {
382 alloc_nid_failed(sbi, new_nid);
383 return PTR_ERR(xpage);
384 }
385 alloc_nid_done(sbi, new_nid);
386 }
387
388 xattr_addr = page_address(xpage);
389 memcpy(xattr_addr, txattr_addr + inline_size, PAGE_SIZE -
390 sizeof(struct node_footer));
391 set_page_dirty(xpage);
392 f2fs_put_page(xpage, 1);
393
394 /* need to checkpoint during fsync */
395 F2FS_I(inode)->xattr_ver = cur_cp_version(F2FS_CKPT(sbi));
396 return 0;
397}
398
af48b85b
JK
399int f2fs_getxattr(struct inode *inode, int name_index, const char *name,
400 void *buffer, size_t buffer_size)
401{
af48b85b 402 struct f2fs_xattr_entry *entry;
65985d93 403 void *base_addr;
dd9cfe23 404 int error = 0;
9836b8b9 405 size_t value_len, name_len;
af48b85b
JK
406
407 if (name == NULL)
408 return -EINVAL;
409 name_len = strlen(name);
410
65985d93
JK
411 base_addr = read_all_xattrs(inode, NULL);
412 if (!base_addr)
413 return -ENOMEM;
af48b85b 414
65985d93 415 entry = __find_xattr(base_addr, name_index, name_len, name);
dd9cfe23 416 if (IS_XATTR_LAST_ENTRY(entry)) {
af48b85b
JK
417 error = -ENODATA;
418 goto cleanup;
419 }
420
421 value_len = le16_to_cpu(entry->e_value_size);
422
423 if (buffer && value_len > buffer_size) {
424 error = -ERANGE;
425 goto cleanup;
426 }
427
428 if (buffer) {
429 char *pval = entry->e_name + entry->e_name_len;
430 memcpy(buffer, pval, value_len);
431 }
432 error = value_len;
433
434cleanup:
65985d93 435 kzfree(base_addr);
af48b85b
JK
436 return error;
437}
438
439ssize_t f2fs_listxattr(struct dentry *dentry, char *buffer, size_t buffer_size)
440{
441 struct inode *inode = dentry->d_inode;
af48b85b 442 struct f2fs_xattr_entry *entry;
af48b85b
JK
443 void *base_addr;
444 int error = 0;
445 size_t rest = buffer_size;
446
65985d93
JK
447 base_addr = read_all_xattrs(inode, NULL);
448 if (!base_addr)
449 return -ENOMEM;
af48b85b
JK
450
451 list_for_each_xattr(entry, base_addr) {
452 const struct xattr_handler *handler =
453 f2fs_xattr_handler(entry->e_name_index);
454 size_t size;
455
456 if (!handler)
457 continue;
458
459 size = handler->list(dentry, buffer, rest, entry->e_name,
460 entry->e_name_len, handler->flags);
461 if (buffer && size > rest) {
462 error = -ERANGE;
463 goto cleanup;
464 }
465
466 if (buffer)
467 buffer += size;
468 rest -= size;
469 }
470 error = buffer_size - rest;
471cleanup:
65985d93 472 kzfree(base_addr);
af48b85b
JK
473 return error;
474}
475
52ab9560
RK
476static int __f2fs_setxattr(struct inode *inode, int name_index,
477 const char *name, const void *value, size_t value_len,
478 struct page *ipage)
af48b85b 479{
af48b85b 480 struct f2fs_inode_info *fi = F2FS_I(inode);
af48b85b 481 struct f2fs_xattr_entry *here, *last;
af48b85b 482 void *base_addr;
65985d93 483 int found, newsize;
9836b8b9 484 size_t name_len;
65985d93
JK
485 __u32 new_hsize;
486 int error = -ENOMEM;
af48b85b
JK
487
488 if (name == NULL)
489 return -EINVAL;
af48b85b
JK
490
491 if (value == NULL)
492 value_len = 0;
493
7c909772
NJ
494 name_len = strlen(name);
495
65985d93 496 if (name_len > F2FS_NAME_LEN || value_len > MAX_VALUE_LEN(inode))
af48b85b
JK
497 return -ERANGE;
498
65985d93
JK
499 base_addr = read_all_xattrs(inode, ipage);
500 if (!base_addr)
501 goto exit;
af48b85b
JK
502
503 /* find entry with wanted name. */
dd9cfe23 504 here = __find_xattr(base_addr, name_index, name_len, name);
af48b85b 505
dd9cfe23 506 found = IS_XATTR_LAST_ENTRY(here) ? 0 : 1;
af48b85b
JK
507 last = here;
508
509 while (!IS_XATTR_LAST_ENTRY(last))
510 last = XATTR_NEXT_ENTRY(last);
511
512 newsize = XATTR_ALIGN(sizeof(struct f2fs_xattr_entry) +
513 name_len + value_len);
514
515 /* 1. Check space */
516 if (value) {
65985d93
JK
517 int free;
518 /*
519 * If value is NULL, it is remove operation.
af48b85b
JK
520 * In case of update operation, we caculate free.
521 */
65985d93 522 free = MIN_OFFSET(inode) - ((char *)last - (char *)base_addr);
af48b85b 523 if (found)
cc3de6a3 524 free = free + ENTRY_SIZE(here);
af48b85b 525
6bacf52f 526 if (unlikely(free < newsize)) {
af48b85b 527 error = -ENOSPC;
65985d93 528 goto exit;
af48b85b
JK
529 }
530 }
531
532 /* 2. Remove old entry */
533 if (found) {
65985d93
JK
534 /*
535 * If entry is found, remove old entry.
af48b85b
JK
536 * If not found, remove operation is not needed.
537 */
538 struct f2fs_xattr_entry *next = XATTR_NEXT_ENTRY(here);
539 int oldsize = ENTRY_SIZE(here);
540
541 memmove(here, next, (char *)last - (char *)next);
542 last = (struct f2fs_xattr_entry *)((char *)last - oldsize);
543 memset(last, 0, oldsize);
544 }
545
65985d93
JK
546 new_hsize = (char *)last - (char *)base_addr;
547
af48b85b
JK
548 /* 3. Write new entry */
549 if (value) {
65985d93
JK
550 char *pval;
551 /*
552 * Before we come here, old entry is removed.
553 * We just write new entry.
554 */
af48b85b
JK
555 memset(last, 0, newsize);
556 last->e_name_index = name_index;
557 last->e_name_len = name_len;
558 memcpy(last->e_name, name, name_len);
559 pval = last->e_name + name_len;
560 memcpy(pval, value, value_len);
561 last->e_value_size = cpu_to_le16(value_len);
65985d93 562 new_hsize += newsize;
af48b85b
JK
563 }
564
65985d93
JK
565 error = write_all_xattrs(inode, new_hsize, base_addr, ipage);
566 if (error)
567 goto exit;
af48b85b
JK
568
569 if (is_inode_flag_set(fi, FI_ACL_MODE)) {
570 inode->i_mode = fi->i_acl_mode;
571 inode->i_ctime = CURRENT_TIME;
572 clear_inode_flag(fi, FI_ACL_MODE);
573 }
e518ff81 574
8ae8f162
JK
575 if (ipage)
576 update_inode(inode, ipage);
577 else
578 update_inode_page(inode);
7c909772 579exit:
65985d93 580 kzfree(base_addr);
af48b85b
JK
581 return error;
582}
52ab9560
RK
583
584int f2fs_setxattr(struct inode *inode, int name_index, const char *name,
585 const void *value, size_t value_len, struct page *ipage)
586{
587 struct f2fs_sb_info *sbi = F2FS_SB(inode->i_sb);
52ab9560
RK
588 int err;
589
590 f2fs_balance_fs(sbi);
591
e479556b 592 f2fs_lock_op(sbi);
d928bfbf
JK
593 /* protect xattr_ver */
594 down_write(&F2FS_I(inode)->i_sem);
52ab9560 595 err = __f2fs_setxattr(inode, name_index, name, value, value_len, ipage);
d928bfbf 596 up_write(&F2FS_I(inode)->i_sem);
e479556b 597 f2fs_unlock_op(sbi);
52ab9560
RK
598
599 return err;
600}