Commit | Line | Data |
---|---|---|
237fead6 MH |
1 | /** |
2 | * eCryptfs: Linux filesystem encryption layer | |
3 | * This is where eCryptfs coordinates the symmetric encryption and | |
4 | * decryption of the file data as it passes between the lower | |
5 | * encrypted file and the upper decrypted file. | |
6 | * | |
7 | * Copyright (C) 1997-2003 Erez Zadok | |
8 | * Copyright (C) 2001-2003 Stony Brook University | |
dd2a3b7a | 9 | * Copyright (C) 2004-2007 International Business Machines Corp. |
237fead6 MH |
10 | * Author(s): Michael A. Halcrow <mahalcro@us.ibm.com> |
11 | * | |
12 | * This program is free software; you can redistribute it and/or | |
13 | * modify it under the terms of the GNU General Public License as | |
14 | * published by the Free Software Foundation; either version 2 of the | |
15 | * License, or (at your option) any later version. | |
16 | * | |
17 | * This program is distributed in the hope that it will be useful, but | |
18 | * WITHOUT ANY WARRANTY; without even the implied warranty of | |
19 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU | |
20 | * General Public License for more details. | |
21 | * | |
22 | * You should have received a copy of the GNU General Public License | |
23 | * along with this program; if not, write to the Free Software | |
24 | * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA | |
25 | * 02111-1307, USA. | |
26 | */ | |
27 | ||
28 | #include <linux/pagemap.h> | |
29 | #include <linux/writeback.h> | |
30 | #include <linux/page-flags.h> | |
31 | #include <linux/mount.h> | |
32 | #include <linux/file.h> | |
33 | #include <linux/crypto.h> | |
34 | #include <linux/scatterlist.h> | |
5a0e3ad6 | 35 | #include <linux/slab.h> |
0a688ad7 | 36 | #include <asm/unaligned.h> |
237fead6 MH |
37 | #include "ecryptfs_kernel.h" |
38 | ||
237fead6 | 39 | /** |
16a72c45 | 40 | * ecryptfs_get_locked_page |
237fead6 MH |
41 | * |
42 | * Get one page from cache or lower f/s, return error otherwise. | |
43 | * | |
16a72c45 | 44 | * Returns locked and up-to-date page (if ok), with increased |
237fead6 MH |
45 | * refcnt. |
46 | */ | |
02bd9799 | 47 | struct page *ecryptfs_get_locked_page(struct inode *inode, loff_t index) |
237fead6 | 48 | { |
02bd9799 | 49 | struct page *page = read_mapping_page(inode->i_mapping, index, NULL); |
16a72c45 MH |
50 | if (!IS_ERR(page)) |
51 | lock_page(page); | |
52 | return page; | |
237fead6 MH |
53 | } |
54 | ||
237fead6 MH |
55 | /** |
56 | * ecryptfs_writepage | |
57 | * @page: Page that is locked before this call is made | |
58 | * | |
59 | * Returns zero on success; non-zero otherwise | |
60 | */ | |
61 | static int ecryptfs_writepage(struct page *page, struct writeback_control *wbc) | |
62 | { | |
237fead6 MH |
63 | int rc; |
64 | ||
0216f7f7 | 65 | rc = ecryptfs_encrypt_page(page); |
237fead6 MH |
66 | if (rc) { |
67 | ecryptfs_printk(KERN_WARNING, "Error encrypting " | |
68 | "page (upper index [0x%.16x])\n", page->index); | |
69 | ClearPageUptodate(page); | |
70 | goto out; | |
71 | } | |
72 | SetPageUptodate(page); | |
73 | unlock_page(page); | |
74 | out: | |
75 | return rc; | |
76 | } | |
77 | ||
f4e60e6b TH |
78 | static void strip_xattr_flag(char *page_virt, |
79 | struct ecryptfs_crypt_stat *crypt_stat) | |
80 | { | |
81 | if (crypt_stat->flags & ECRYPTFS_METADATA_IN_XATTR) { | |
82 | size_t written; | |
83 | ||
84 | crypt_stat->flags &= ~ECRYPTFS_METADATA_IN_XATTR; | |
85 | ecryptfs_write_crypt_stat_flags(page_virt, crypt_stat, | |
86 | &written); | |
87 | crypt_stat->flags |= ECRYPTFS_METADATA_IN_XATTR; | |
88 | } | |
89 | } | |
90 | ||
e77a56dd MH |
91 | /** |
92 | * Header Extent: | |
93 | * Octets 0-7: Unencrypted file size (big-endian) | |
94 | * Octets 8-15: eCryptfs special marker | |
95 | * Octets 16-19: Flags | |
96 | * Octet 16: File format version number (between 0 and 255) | |
97 | * Octets 17-18: Reserved | |
98 | * Octet 19: Bit 1 (lsb): Reserved | |
99 | * Bit 2: Encrypted? | |
100 | * Bits 3-8: Reserved | |
101 | * Octets 20-23: Header extent size (big-endian) | |
102 | * Octets 24-25: Number of header extents at front of file | |
103 | * (big-endian) | |
104 | * Octet 26: Begin RFC 2440 authentication token packet set | |
105 | */ | |
237fead6 | 106 | |
bf12be1c MH |
107 | /** |
108 | * ecryptfs_copy_up_encrypted_with_header | |
109 | * @page: Sort of a ``virtual'' representation of the encrypted lower | |
110 | * file. The actual lower file does not have the metadata in | |
111 | * the header. This is locked. | |
112 | * @crypt_stat: The eCryptfs inode's cryptographic context | |
113 | * | |
114 | * The ``view'' is the version of the file that userspace winds up | |
115 | * seeing, with the header information inserted. | |
116 | */ | |
117 | static int | |
118 | ecryptfs_copy_up_encrypted_with_header(struct page *page, | |
119 | struct ecryptfs_crypt_stat *crypt_stat) | |
120 | { | |
121 | loff_t extent_num_in_page = 0; | |
122 | loff_t num_extents_per_page = (PAGE_CACHE_SIZE | |
123 | / crypt_stat->extent_size); | |
124 | int rc = 0; | |
125 | ||
126 | while (extent_num_in_page < num_extents_per_page) { | |
d6a13c17 MH |
127 | loff_t view_extent_num = ((((loff_t)page->index) |
128 | * num_extents_per_page) | |
bf12be1c | 129 | + extent_num_in_page); |
cc11beff | 130 | size_t num_header_extents_at_front = |
fa3ef1cb | 131 | (crypt_stat->metadata_size / crypt_stat->extent_size); |
bf12be1c | 132 | |
cc11beff | 133 | if (view_extent_num < num_header_extents_at_front) { |
bf12be1c MH |
134 | /* This is a header extent */ |
135 | char *page_virt; | |
136 | ||
137 | page_virt = kmap_atomic(page, KM_USER0); | |
138 | memset(page_virt, 0, PAGE_CACHE_SIZE); | |
139 | /* TODO: Support more than one header extent */ | |
140 | if (view_extent_num == 0) { | |
157f1071 TH |
141 | size_t written; |
142 | ||
bf12be1c MH |
143 | rc = ecryptfs_read_xattr_region( |
144 | page_virt, page->mapping->host); | |
f4e60e6b | 145 | strip_xattr_flag(page_virt + 16, crypt_stat); |
157f1071 TH |
146 | ecryptfs_write_header_metadata(page_virt + 20, |
147 | crypt_stat, | |
148 | &written); | |
bf12be1c MH |
149 | } |
150 | kunmap_atomic(page_virt, KM_USER0); | |
151 | flush_dcache_page(page); | |
152 | if (rc) { | |
bf12be1c | 153 | printk(KERN_ERR "%s: Error reading xattr " |
18d1dbf1 | 154 | "region; rc = [%d]\n", __func__, rc); |
bf12be1c MH |
155 | goto out; |
156 | } | |
bf12be1c MH |
157 | } else { |
158 | /* This is an encrypted data extent */ | |
159 | loff_t lower_offset = | |
cc11beff | 160 | ((view_extent_num * crypt_stat->extent_size) |
fa3ef1cb | 161 | - crypt_stat->metadata_size); |
bf12be1c MH |
162 | |
163 | rc = ecryptfs_read_lower_page_segment( | |
164 | page, (lower_offset >> PAGE_CACHE_SHIFT), | |
165 | (lower_offset & ~PAGE_CACHE_MASK), | |
166 | crypt_stat->extent_size, page->mapping->host); | |
167 | if (rc) { | |
168 | printk(KERN_ERR "%s: Error attempting to read " | |
169 | "extent at offset [%lld] in the lower " | |
18d1dbf1 | 170 | "file; rc = [%d]\n", __func__, |
bf12be1c MH |
171 | lower_offset, rc); |
172 | goto out; | |
173 | } | |
174 | } | |
175 | extent_num_in_page++; | |
176 | } | |
177 | out: | |
178 | return rc; | |
179 | } | |
180 | ||
237fead6 MH |
181 | /** |
182 | * ecryptfs_readpage | |
bf12be1c MH |
183 | * @file: An eCryptfs file |
184 | * @page: Page from eCryptfs inode mapping into which to stick the read data | |
237fead6 MH |
185 | * |
186 | * Read in a page, decrypting if necessary. | |
187 | * | |
188 | * Returns zero on success; non-zero on error. | |
189 | */ | |
190 | static int ecryptfs_readpage(struct file *file, struct page *page) | |
191 | { | |
bf12be1c | 192 | struct ecryptfs_crypt_stat *crypt_stat = |
bef5bc24 | 193 | &ecryptfs_inode_to_private(page->mapping->host)->crypt_stat; |
237fead6 | 194 | int rc = 0; |
237fead6 | 195 | |
237fead6 | 196 | if (!crypt_stat |
e2bd99ec MH |
197 | || !(crypt_stat->flags & ECRYPTFS_ENCRYPTED) |
198 | || (crypt_stat->flags & ECRYPTFS_NEW_FILE)) { | |
237fead6 MH |
199 | ecryptfs_printk(KERN_DEBUG, |
200 | "Passing through unencrypted page\n"); | |
bf12be1c MH |
201 | rc = ecryptfs_read_lower_page_segment(page, page->index, 0, |
202 | PAGE_CACHE_SIZE, | |
203 | page->mapping->host); | |
e77a56dd MH |
204 | } else if (crypt_stat->flags & ECRYPTFS_VIEW_AS_ENCRYPTED) { |
205 | if (crypt_stat->flags & ECRYPTFS_METADATA_IN_XATTR) { | |
bf12be1c MH |
206 | rc = ecryptfs_copy_up_encrypted_with_header(page, |
207 | crypt_stat); | |
208 | if (rc) { | |
209 | printk(KERN_ERR "%s: Error attempting to copy " | |
210 | "the encrypted content from the lower " | |
211 | "file whilst inserting the metadata " | |
212 | "from the xattr into the header; rc = " | |
18d1dbf1 | 213 | "[%d]\n", __func__, rc); |
bf12be1c | 214 | goto out; |
e77a56dd | 215 | } |
bf12be1c | 216 | |
e77a56dd | 217 | } else { |
bf12be1c MH |
218 | rc = ecryptfs_read_lower_page_segment( |
219 | page, page->index, 0, PAGE_CACHE_SIZE, | |
220 | page->mapping->host); | |
e77a56dd MH |
221 | if (rc) { |
222 | printk(KERN_ERR "Error reading page; rc = " | |
223 | "[%d]\n", rc); | |
224 | goto out; | |
225 | } | |
226 | } | |
237fead6 | 227 | } else { |
0216f7f7 | 228 | rc = ecryptfs_decrypt_page(page); |
237fead6 | 229 | if (rc) { |
237fead6 MH |
230 | ecryptfs_printk(KERN_ERR, "Error decrypting page; " |
231 | "rc = [%d]\n", rc); | |
232 | goto out; | |
233 | } | |
234 | } | |
237fead6 | 235 | out: |
16a72c45 MH |
236 | if (rc) |
237 | ClearPageUptodate(page); | |
238 | else | |
239 | SetPageUptodate(page); | |
237fead6 MH |
240 | ecryptfs_printk(KERN_DEBUG, "Unlocking page with index = [0x%.16x]\n", |
241 | page->index); | |
242 | unlock_page(page); | |
243 | return rc; | |
244 | } | |
245 | ||
dd2a3b7a MH |
246 | /** |
247 | * Called with lower inode mutex held. | |
248 | */ | |
237fead6 MH |
249 | static int fill_zeros_to_end_of_page(struct page *page, unsigned int to) |
250 | { | |
251 | struct inode *inode = page->mapping->host; | |
252 | int end_byte_in_page; | |
237fead6 | 253 | |
9d8b8ce5 MH |
254 | if ((i_size_read(inode) / PAGE_CACHE_SIZE) != page->index) |
255 | goto out; | |
256 | end_byte_in_page = i_size_read(inode) % PAGE_CACHE_SIZE; | |
257 | if (to > end_byte_in_page) | |
258 | end_byte_in_page = to; | |
eebd2aa3 | 259 | zero_user_segment(page, end_byte_in_page, PAGE_CACHE_SIZE); |
237fead6 | 260 | out: |
9d8b8ce5 | 261 | return 0; |
237fead6 MH |
262 | } |
263 | ||
e4465fda | 264 | /** |
807b7ebe | 265 | * ecryptfs_write_begin |
e4465fda | 266 | * @file: The eCryptfs file |
807b7ebe BP |
267 | * @mapping: The eCryptfs object |
268 | * @pos: The file offset at which to start writing | |
269 | * @len: Length of the write | |
270 | * @flags: Various flags | |
271 | * @pagep: Pointer to return the page | |
272 | * @fsdata: Pointer to return fs data (unused) | |
e4465fda MH |
273 | * |
274 | * This function must zero any hole we create | |
275 | * | |
276 | * Returns zero on success; non-zero otherwise | |
277 | */ | |
807b7ebe BP |
278 | static int ecryptfs_write_begin(struct file *file, |
279 | struct address_space *mapping, | |
280 | loff_t pos, unsigned len, unsigned flags, | |
281 | struct page **pagep, void **fsdata) | |
237fead6 | 282 | { |
807b7ebe BP |
283 | pgoff_t index = pos >> PAGE_CACHE_SHIFT; |
284 | struct page *page; | |
7a3f595c | 285 | loff_t prev_page_end_size; |
e4465fda | 286 | int rc = 0; |
237fead6 | 287 | |
54566b2c | 288 | page = grab_cache_page_write_begin(mapping, index, flags); |
807b7ebe BP |
289 | if (!page) |
290 | return -ENOMEM; | |
291 | *pagep = page; | |
292 | ||
16a72c45 | 293 | if (!PageUptodate(page)) { |
e4465fda | 294 | struct ecryptfs_crypt_stat *crypt_stat = |
bef5bc24 | 295 | &ecryptfs_inode_to_private(mapping->host)->crypt_stat; |
e4465fda MH |
296 | |
297 | if (!(crypt_stat->flags & ECRYPTFS_ENCRYPTED) | |
298 | || (crypt_stat->flags & ECRYPTFS_NEW_FILE)) { | |
299 | rc = ecryptfs_read_lower_page_segment( | |
807b7ebe | 300 | page, index, 0, PAGE_CACHE_SIZE, mapping->host); |
e4465fda MH |
301 | if (rc) { |
302 | printk(KERN_ERR "%s: Error attemping to read " | |
303 | "lower page segment; rc = [%d]\n", | |
18d1dbf1 | 304 | __func__, rc); |
e4465fda MH |
305 | ClearPageUptodate(page); |
306 | goto out; | |
307 | } else | |
308 | SetPageUptodate(page); | |
309 | } else if (crypt_stat->flags & ECRYPTFS_VIEW_AS_ENCRYPTED) { | |
310 | if (crypt_stat->flags & ECRYPTFS_METADATA_IN_XATTR) { | |
311 | rc = ecryptfs_copy_up_encrypted_with_header( | |
312 | page, crypt_stat); | |
313 | if (rc) { | |
314 | printk(KERN_ERR "%s: Error attempting " | |
315 | "to copy the encrypted content " | |
316 | "from the lower file whilst " | |
317 | "inserting the metadata from " | |
318 | "the xattr into the header; rc " | |
18d1dbf1 | 319 | "= [%d]\n", __func__, rc); |
e4465fda MH |
320 | ClearPageUptodate(page); |
321 | goto out; | |
322 | } | |
323 | SetPageUptodate(page); | |
324 | } else { | |
325 | rc = ecryptfs_read_lower_page_segment( | |
807b7ebe BP |
326 | page, index, 0, PAGE_CACHE_SIZE, |
327 | mapping->host); | |
e4465fda MH |
328 | if (rc) { |
329 | printk(KERN_ERR "%s: Error reading " | |
330 | "page; rc = [%d]\n", | |
18d1dbf1 | 331 | __func__, rc); |
e4465fda MH |
332 | ClearPageUptodate(page); |
333 | goto out; | |
334 | } | |
335 | SetPageUptodate(page); | |
336 | } | |
337 | } else { | |
338 | rc = ecryptfs_decrypt_page(page); | |
339 | if (rc) { | |
340 | printk(KERN_ERR "%s: Error decrypting page " | |
341 | "at index [%ld]; rc = [%d]\n", | |
18d1dbf1 | 342 | __func__, page->index, rc); |
e4465fda MH |
343 | ClearPageUptodate(page); |
344 | goto out; | |
345 | } | |
16a72c45 | 346 | SetPageUptodate(page); |
e4465fda | 347 | } |
16a72c45 | 348 | } |
807b7ebe | 349 | prev_page_end_size = ((loff_t)index << PAGE_CACHE_SHIFT); |
e4465fda MH |
350 | /* If creating a page or more of holes, zero them out via truncate. |
351 | * Note, this will increase i_size. */ | |
807b7ebe | 352 | if (index != 0) { |
7a3f595c | 353 | if (prev_page_end_size > i_size_read(page->mapping->host)) { |
240e2df5 | 354 | rc = ecryptfs_truncate(file->f_path.dentry, |
7a3f595c | 355 | prev_page_end_size); |
240e2df5 | 356 | if (rc) { |
e4465fda | 357 | printk(KERN_ERR "%s: Error on attempt to " |
240e2df5 | 358 | "truncate to (higher) offset [%lld];" |
18d1dbf1 | 359 | " rc = [%d]\n", __func__, |
e4465fda | 360 | prev_page_end_size, rc); |
240e2df5 MH |
361 | goto out; |
362 | } | |
53a2731f | 363 | } |
7a3f595c | 364 | } |
e4465fda MH |
365 | /* Writing to a new page, and creating a small hole from start |
366 | * of page? Zero it out. */ | |
807b7ebe BP |
367 | if ((i_size_read(mapping->host) == prev_page_end_size) |
368 | && (pos != 0)) | |
eebd2aa3 | 369 | zero_user(page, 0, PAGE_CACHE_SIZE); |
237fead6 MH |
370 | out: |
371 | return rc; | |
372 | } | |
373 | ||
237fead6 MH |
374 | /** |
375 | * ecryptfs_write_inode_size_to_header | |
376 | * | |
377 | * Writes the lower file size to the first 8 bytes of the header. | |
378 | * | |
379 | * Returns zero on success; non-zero on error. | |
380 | */ | |
0216f7f7 | 381 | static int ecryptfs_write_inode_size_to_header(struct inode *ecryptfs_inode) |
237fead6 | 382 | { |
0216f7f7 MH |
383 | char *file_size_virt; |
384 | int rc; | |
237fead6 | 385 | |
0216f7f7 MH |
386 | file_size_virt = kmalloc(sizeof(u64), GFP_KERNEL); |
387 | if (!file_size_virt) { | |
388 | rc = -ENOMEM; | |
ae73fc09 MH |
389 | goto out; |
390 | } | |
0a688ad7 | 391 | put_unaligned_be64(i_size_read(ecryptfs_inode), file_size_virt); |
0216f7f7 MH |
392 | rc = ecryptfs_write_lower(ecryptfs_inode, file_size_virt, 0, |
393 | sizeof(u64)); | |
394 | kfree(file_size_virt); | |
96a7b9c2 | 395 | if (rc < 0) |
0216f7f7 | 396 | printk(KERN_ERR "%s: Error writing file size to header; " |
18d1dbf1 | 397 | "rc = [%d]\n", __func__, rc); |
96a7b9c2 TH |
398 | else |
399 | rc = 0; | |
237fead6 MH |
400 | out: |
401 | return rc; | |
402 | } | |
403 | ||
0216f7f7 MH |
404 | struct kmem_cache *ecryptfs_xattr_cache; |
405 | ||
406 | static int ecryptfs_write_inode_size_to_xattr(struct inode *ecryptfs_inode) | |
dd2a3b7a MH |
407 | { |
408 | ssize_t size; | |
409 | void *xattr_virt; | |
0216f7f7 MH |
410 | struct dentry *lower_dentry = |
411 | ecryptfs_inode_to_private(ecryptfs_inode)->lower_file->f_dentry; | |
412 | struct inode *lower_inode = lower_dentry->d_inode; | |
dd2a3b7a MH |
413 | int rc; |
414 | ||
0216f7f7 MH |
415 | if (!lower_inode->i_op->getxattr || !lower_inode->i_op->setxattr) { |
416 | printk(KERN_WARNING | |
417 | "No support for setting xattr in lower filesystem\n"); | |
418 | rc = -ENOSYS; | |
419 | goto out; | |
420 | } | |
dd2a3b7a MH |
421 | xattr_virt = kmem_cache_alloc(ecryptfs_xattr_cache, GFP_KERNEL); |
422 | if (!xattr_virt) { | |
423 | printk(KERN_ERR "Out of memory whilst attempting to write " | |
424 | "inode size to xattr\n"); | |
425 | rc = -ENOMEM; | |
426 | goto out; | |
427 | } | |
0216f7f7 MH |
428 | mutex_lock(&lower_inode->i_mutex); |
429 | size = lower_inode->i_op->getxattr(lower_dentry, ECRYPTFS_XATTR_NAME, | |
430 | xattr_virt, PAGE_CACHE_SIZE); | |
dd2a3b7a MH |
431 | if (size < 0) |
432 | size = 8; | |
0a688ad7 | 433 | put_unaligned_be64(i_size_read(ecryptfs_inode), xattr_virt); |
0216f7f7 MH |
434 | rc = lower_inode->i_op->setxattr(lower_dentry, ECRYPTFS_XATTR_NAME, |
435 | xattr_virt, size, 0); | |
436 | mutex_unlock(&lower_inode->i_mutex); | |
dd2a3b7a MH |
437 | if (rc) |
438 | printk(KERN_ERR "Error whilst attempting to write inode size " | |
439 | "to lower file xattr; rc = [%d]\n", rc); | |
440 | kmem_cache_free(ecryptfs_xattr_cache, xattr_virt); | |
441 | out: | |
442 | return rc; | |
443 | } | |
444 | ||
0216f7f7 | 445 | int ecryptfs_write_inode_size_to_metadata(struct inode *ecryptfs_inode) |
dd2a3b7a MH |
446 | { |
447 | struct ecryptfs_crypt_stat *crypt_stat; | |
448 | ||
0216f7f7 | 449 | crypt_stat = &ecryptfs_inode_to_private(ecryptfs_inode)->crypt_stat; |
13a791b4 | 450 | BUG_ON(!(crypt_stat->flags & ECRYPTFS_ENCRYPTED)); |
dd2a3b7a | 451 | if (crypt_stat->flags & ECRYPTFS_METADATA_IN_XATTR) |
0216f7f7 | 452 | return ecryptfs_write_inode_size_to_xattr(ecryptfs_inode); |
dd2a3b7a | 453 | else |
0216f7f7 | 454 | return ecryptfs_write_inode_size_to_header(ecryptfs_inode); |
dd2a3b7a MH |
455 | } |
456 | ||
237fead6 | 457 | /** |
807b7ebe | 458 | * ecryptfs_write_end |
237fead6 | 459 | * @file: The eCryptfs file object |
807b7ebe BP |
460 | * @mapping: The eCryptfs object |
461 | * @pos: The file position | |
462 | * @len: The length of the data (unused) | |
463 | * @copied: The amount of data copied | |
237fead6 | 464 | * @page: The eCryptfs page |
807b7ebe | 465 | * @fsdata: The fsdata (unused) |
237fead6 MH |
466 | * |
467 | * This is where we encrypt the data and pass the encrypted data to | |
468 | * the lower filesystem. In OpenPGP-compatible mode, we operate on | |
469 | * entire underlying packets. | |
470 | */ | |
807b7ebe BP |
471 | static int ecryptfs_write_end(struct file *file, |
472 | struct address_space *mapping, | |
473 | loff_t pos, unsigned len, unsigned copied, | |
474 | struct page *page, void *fsdata) | |
237fead6 | 475 | { |
807b7ebe BP |
476 | pgoff_t index = pos >> PAGE_CACHE_SHIFT; |
477 | unsigned from = pos & (PAGE_CACHE_SIZE - 1); | |
478 | unsigned to = from + copied; | |
479 | struct inode *ecryptfs_inode = mapping->host; | |
bf12be1c | 480 | struct ecryptfs_crypt_stat *crypt_stat = |
bef5bc24 | 481 | &ecryptfs_inode_to_private(ecryptfs_inode)->crypt_stat; |
237fead6 MH |
482 | int rc; |
483 | ||
e2bd99ec | 484 | if (crypt_stat->flags & ECRYPTFS_NEW_FILE) { |
237fead6 MH |
485 | ecryptfs_printk(KERN_DEBUG, "ECRYPTFS_NEW_FILE flag set in " |
486 | "crypt_stat at memory location [%p]\n", crypt_stat); | |
e2bd99ec | 487 | crypt_stat->flags &= ~(ECRYPTFS_NEW_FILE); |
237fead6 MH |
488 | } else |
489 | ecryptfs_printk(KERN_DEBUG, "Not a new file\n"); | |
490 | ecryptfs_printk(KERN_DEBUG, "Calling fill_zeros_to_end_of_page" | |
807b7ebe | 491 | "(page w/ index = [0x%.16x], to = [%d])\n", index, to); |
13a791b4 TH |
492 | if (!(crypt_stat->flags & ECRYPTFS_ENCRYPTED)) { |
493 | rc = ecryptfs_write_lower_page_segment(ecryptfs_inode, page, 0, | |
494 | to); | |
495 | if (!rc) { | |
496 | rc = copied; | |
497 | fsstack_copy_inode_size(ecryptfs_inode, | |
498 | ecryptfs_inode_to_lower(ecryptfs_inode)); | |
499 | } | |
500 | goto out; | |
501 | } | |
bf12be1c | 502 | /* Fills in zeros if 'to' goes beyond inode size */ |
237fead6 MH |
503 | rc = fill_zeros_to_end_of_page(page, to); |
504 | if (rc) { | |
505 | ecryptfs_printk(KERN_WARNING, "Error attempting to fill " | |
807b7ebe | 506 | "zeros in page with index = [0x%.16x]\n", index); |
237fead6 MH |
507 | goto out; |
508 | } | |
0216f7f7 | 509 | rc = ecryptfs_encrypt_page(page); |
237fead6 MH |
510 | if (rc) { |
511 | ecryptfs_printk(KERN_WARNING, "Error encrypting page (upper " | |
807b7ebe | 512 | "index [0x%.16x])\n", index); |
237fead6 MH |
513 | goto out; |
514 | } | |
807b7ebe BP |
515 | if (pos + copied > i_size_read(ecryptfs_inode)) { |
516 | i_size_write(ecryptfs_inode, pos + copied); | |
237fead6 | 517 | ecryptfs_printk(KERN_DEBUG, "Expanded file size to " |
bf12be1c | 518 | "[0x%.16x]\n", i_size_read(ecryptfs_inode)); |
237fead6 | 519 | } |
bf12be1c | 520 | rc = ecryptfs_write_inode_size_to_metadata(ecryptfs_inode); |
dd2a3b7a MH |
521 | if (rc) |
522 | printk(KERN_ERR "Error writing inode size to metadata; " | |
523 | "rc = [%d]\n", rc); | |
807b7ebe BP |
524 | else |
525 | rc = copied; | |
237fead6 | 526 | out: |
807b7ebe BP |
527 | unlock_page(page); |
528 | page_cache_release(page); | |
237fead6 MH |
529 | return rc; |
530 | } | |
531 | ||
237fead6 MH |
532 | static sector_t ecryptfs_bmap(struct address_space *mapping, sector_t block) |
533 | { | |
534 | int rc = 0; | |
535 | struct inode *inode; | |
536 | struct inode *lower_inode; | |
537 | ||
538 | inode = (struct inode *)mapping->host; | |
539 | lower_inode = ecryptfs_inode_to_lower(inode); | |
540 | if (lower_inode->i_mapping->a_ops->bmap) | |
541 | rc = lower_inode->i_mapping->a_ops->bmap(lower_inode->i_mapping, | |
542 | block); | |
543 | return rc; | |
544 | } | |
545 | ||
7f09410b | 546 | const struct address_space_operations ecryptfs_aops = { |
237fead6 MH |
547 | .writepage = ecryptfs_writepage, |
548 | .readpage = ecryptfs_readpage, | |
807b7ebe BP |
549 | .write_begin = ecryptfs_write_begin, |
550 | .write_end = ecryptfs_write_end, | |
237fead6 | 551 | .bmap = ecryptfs_bmap, |
237fead6 | 552 | }; |