xref: /openbmc/linux/fs/ecryptfs/ecryptfs_kernel.h (revision 39b6f3aa)
1 /**
2  * eCryptfs: Linux filesystem encryption layer
3  * Kernel declarations.
4  *
5  * Copyright (C) 1997-2003 Erez Zadok
6  * Copyright (C) 2001-2003 Stony Brook University
7  * Copyright (C) 2004-2008 International Business Machines Corp.
8  *   Author(s): Michael A. Halcrow <mahalcro@us.ibm.com>
9  *              Trevor S. Highland <trevor.highland@gmail.com>
10  *              Tyler Hicks <tyhicks@ou.edu>
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 #ifndef ECRYPTFS_KERNEL_H
29 #define ECRYPTFS_KERNEL_H
30 
31 #include <keys/user-type.h>
32 #include <keys/encrypted-type.h>
33 #include <linux/fs.h>
34 #include <linux/fs_stack.h>
35 #include <linux/namei.h>
36 #include <linux/scatterlist.h>
37 #include <linux/hash.h>
38 #include <linux/nsproxy.h>
39 #include <linux/backing-dev.h>
40 #include <linux/ecryptfs.h>
41 #include <linux/crypto.h>
42 
43 #define ECRYPTFS_DEFAULT_IV_BYTES 16
44 #define ECRYPTFS_DEFAULT_EXTENT_SIZE 4096
45 #define ECRYPTFS_MINIMUM_HEADER_EXTENT_SIZE 8192
46 #define ECRYPTFS_DEFAULT_MSG_CTX_ELEMS 32
47 #define ECRYPTFS_DEFAULT_SEND_TIMEOUT HZ
48 #define ECRYPTFS_MAX_MSG_CTX_TTL (HZ*3)
49 #define ECRYPTFS_DEFAULT_NUM_USERS 4
50 #define ECRYPTFS_MAX_NUM_USERS 32768
51 #define ECRYPTFS_XATTR_NAME "user.ecryptfs"
52 
53 void ecryptfs_dump_auth_tok(struct ecryptfs_auth_tok *auth_tok);
54 extern void ecryptfs_to_hex(char *dst, char *src, size_t src_size);
55 extern void ecryptfs_from_hex(char *dst, char *src, int dst_size);
56 
57 struct ecryptfs_key_record {
58 	unsigned char type;
59 	size_t enc_key_size;
60 	unsigned char sig[ECRYPTFS_SIG_SIZE];
61 	unsigned char enc_key[ECRYPTFS_MAX_ENCRYPTED_KEY_BYTES];
62 };
63 
64 struct ecryptfs_auth_tok_list {
65 	struct ecryptfs_auth_tok *auth_tok;
66 	struct list_head list;
67 };
68 
69 struct ecryptfs_crypt_stat;
70 struct ecryptfs_mount_crypt_stat;
71 
72 struct ecryptfs_page_crypt_context {
73 	struct page *page;
74 #define ECRYPTFS_PREPARE_COMMIT_MODE 0
75 #define ECRYPTFS_WRITEPAGE_MODE      1
76 	unsigned int mode;
77 	union {
78 		struct file *lower_file;
79 		struct writeback_control *wbc;
80 	} param;
81 };
82 
83 #if defined(CONFIG_ENCRYPTED_KEYS) || defined(CONFIG_ENCRYPTED_KEYS_MODULE)
84 static inline struct ecryptfs_auth_tok *
85 ecryptfs_get_encrypted_key_payload_data(struct key *key)
86 {
87 	if (key->type == &key_type_encrypted)
88 		return (struct ecryptfs_auth_tok *)
89 			(&((struct encrypted_key_payload *)key->payload.data)->payload_data);
90 	else
91 		return NULL;
92 }
93 
94 static inline struct key *ecryptfs_get_encrypted_key(char *sig)
95 {
96 	return request_key(&key_type_encrypted, sig, NULL);
97 }
98 
99 #else
100 static inline struct ecryptfs_auth_tok *
101 ecryptfs_get_encrypted_key_payload_data(struct key *key)
102 {
103 	return NULL;
104 }
105 
106 static inline struct key *ecryptfs_get_encrypted_key(char *sig)
107 {
108 	return ERR_PTR(-ENOKEY);
109 }
110 
111 #endif /* CONFIG_ENCRYPTED_KEYS */
112 
113 static inline struct ecryptfs_auth_tok *
114 ecryptfs_get_key_payload_data(struct key *key)
115 {
116 	struct ecryptfs_auth_tok *auth_tok;
117 
118 	auth_tok = ecryptfs_get_encrypted_key_payload_data(key);
119 	if (!auth_tok)
120 		return (struct ecryptfs_auth_tok *)
121 			(((struct user_key_payload *)key->payload.data)->data);
122 	else
123 		return auth_tok;
124 }
125 
126 #define ECRYPTFS_MAX_KEYSET_SIZE 1024
127 #define ECRYPTFS_MAX_CIPHER_NAME_SIZE 32
128 #define ECRYPTFS_MAX_NUM_ENC_KEYS 64
129 #define ECRYPTFS_MAX_IV_BYTES 16	/* 128 bits */
130 #define ECRYPTFS_SALT_BYTES 2
131 #define MAGIC_ECRYPTFS_MARKER 0x3c81b7f5
132 #define MAGIC_ECRYPTFS_MARKER_SIZE_BYTES 8	/* 4*2 */
133 #define ECRYPTFS_FILE_SIZE_BYTES (sizeof(u64))
134 #define ECRYPTFS_SIZE_AND_MARKER_BYTES (ECRYPTFS_FILE_SIZE_BYTES \
135 					+ MAGIC_ECRYPTFS_MARKER_SIZE_BYTES)
136 #define ECRYPTFS_DEFAULT_CIPHER "aes"
137 #define ECRYPTFS_DEFAULT_KEY_BYTES 16
138 #define ECRYPTFS_DEFAULT_HASH "md5"
139 #define ECRYPTFS_TAG_70_DIGEST ECRYPTFS_DEFAULT_HASH
140 #define ECRYPTFS_TAG_1_PACKET_TYPE 0x01
141 #define ECRYPTFS_TAG_3_PACKET_TYPE 0x8C
142 #define ECRYPTFS_TAG_11_PACKET_TYPE 0xED
143 #define ECRYPTFS_TAG_64_PACKET_TYPE 0x40
144 #define ECRYPTFS_TAG_65_PACKET_TYPE 0x41
145 #define ECRYPTFS_TAG_66_PACKET_TYPE 0x42
146 #define ECRYPTFS_TAG_67_PACKET_TYPE 0x43
147 #define ECRYPTFS_TAG_70_PACKET_TYPE 0x46 /* FNEK-encrypted filename
148 					  * as dentry name */
149 #define ECRYPTFS_TAG_71_PACKET_TYPE 0x47 /* FNEK-encrypted filename in
150 					  * metadata */
151 #define ECRYPTFS_TAG_72_PACKET_TYPE 0x48 /* FEK-encrypted filename as
152 					  * dentry name */
153 #define ECRYPTFS_TAG_73_PACKET_TYPE 0x49 /* FEK-encrypted filename as
154 					  * metadata */
155 #define ECRYPTFS_MIN_PKT_LEN_SIZE 1 /* Min size to specify packet length */
156 #define ECRYPTFS_MAX_PKT_LEN_SIZE 2 /* Pass at least this many bytes to
157 				     * ecryptfs_parse_packet_length() and
158 				     * ecryptfs_write_packet_length()
159 				     */
160 /* Constraint: ECRYPTFS_FILENAME_MIN_RANDOM_PREPEND_BYTES >=
161  * ECRYPTFS_MAX_IV_BYTES */
162 #define ECRYPTFS_FILENAME_MIN_RANDOM_PREPEND_BYTES 16
163 #define ECRYPTFS_NON_NULL 0x42 /* A reasonable substitute for NULL */
164 #define MD5_DIGEST_SIZE 16
165 #define ECRYPTFS_TAG_70_DIGEST_SIZE MD5_DIGEST_SIZE
166 #define ECRYPTFS_TAG_70_MIN_METADATA_SIZE (1 + ECRYPTFS_MIN_PKT_LEN_SIZE \
167 					   + ECRYPTFS_SIG_SIZE + 1 + 1)
168 #define ECRYPTFS_TAG_70_MAX_METADATA_SIZE (1 + ECRYPTFS_MAX_PKT_LEN_SIZE \
169 					   + ECRYPTFS_SIG_SIZE + 1 + 1)
170 #define ECRYPTFS_FEK_ENCRYPTED_FILENAME_PREFIX "ECRYPTFS_FEK_ENCRYPTED."
171 #define ECRYPTFS_FEK_ENCRYPTED_FILENAME_PREFIX_SIZE 23
172 #define ECRYPTFS_FNEK_ENCRYPTED_FILENAME_PREFIX "ECRYPTFS_FNEK_ENCRYPTED."
173 #define ECRYPTFS_FNEK_ENCRYPTED_FILENAME_PREFIX_SIZE 24
174 #define ECRYPTFS_ENCRYPTED_DENTRY_NAME_LEN (18 + 1 + 4 + 1 + 32)
175 
176 #ifdef CONFIG_ECRYPT_FS_MESSAGING
177 # define ECRYPTFS_VERSIONING_MASK_MESSAGING (ECRYPTFS_VERSIONING_DEVMISC \
178 					     | ECRYPTFS_VERSIONING_PUBKEY)
179 #else
180 # define ECRYPTFS_VERSIONING_MASK_MESSAGING 0
181 #endif
182 
183 #define ECRYPTFS_VERSIONING_MASK (ECRYPTFS_VERSIONING_PASSPHRASE \
184 				  | ECRYPTFS_VERSIONING_PLAINTEXT_PASSTHROUGH \
185 				  | ECRYPTFS_VERSIONING_XATTR \
186 				  | ECRYPTFS_VERSIONING_MULTKEY \
187 				  | ECRYPTFS_VERSIONING_MASK_MESSAGING \
188 				  | ECRYPTFS_VERSIONING_FILENAME_ENCRYPTION)
189 struct ecryptfs_key_sig {
190 	struct list_head crypt_stat_list;
191 	char keysig[ECRYPTFS_SIG_SIZE_HEX + 1];
192 };
193 
194 struct ecryptfs_filename {
195 	struct list_head crypt_stat_list;
196 #define ECRYPTFS_FILENAME_CONTAINS_DECRYPTED 0x00000001
197 	u32 flags;
198 	u32 seq_no;
199 	char *filename;
200 	char *encrypted_filename;
201 	size_t filename_size;
202 	size_t encrypted_filename_size;
203 	char fnek_sig[ECRYPTFS_SIG_SIZE_HEX];
204 	char dentry_name[ECRYPTFS_ENCRYPTED_DENTRY_NAME_LEN + 1];
205 };
206 
207 /**
208  * This is the primary struct associated with each encrypted file.
209  *
210  * TODO: cache align/pack?
211  */
212 struct ecryptfs_crypt_stat {
213 #define ECRYPTFS_STRUCT_INITIALIZED   0x00000001
214 #define ECRYPTFS_POLICY_APPLIED       0x00000002
215 #define ECRYPTFS_ENCRYPTED            0x00000004
216 #define ECRYPTFS_SECURITY_WARNING     0x00000008
217 #define ECRYPTFS_ENABLE_HMAC          0x00000010
218 #define ECRYPTFS_ENCRYPT_IV_PAGES     0x00000020
219 #define ECRYPTFS_KEY_VALID            0x00000040
220 #define ECRYPTFS_METADATA_IN_XATTR    0x00000080
221 #define ECRYPTFS_VIEW_AS_ENCRYPTED    0x00000100
222 #define ECRYPTFS_KEY_SET              0x00000200
223 #define ECRYPTFS_ENCRYPT_FILENAMES    0x00000400
224 #define ECRYPTFS_ENCFN_USE_MOUNT_FNEK 0x00000800
225 #define ECRYPTFS_ENCFN_USE_FEK        0x00001000
226 #define ECRYPTFS_UNLINK_SIGS          0x00002000
227 #define ECRYPTFS_I_SIZE_INITIALIZED   0x00004000
228 	u32 flags;
229 	unsigned int file_version;
230 	size_t iv_bytes;
231 	size_t metadata_size;
232 	size_t extent_size; /* Data extent size; default is 4096 */
233 	size_t key_size;
234 	size_t extent_shift;
235 	unsigned int extent_mask;
236 	struct ecryptfs_mount_crypt_stat *mount_crypt_stat;
237 	struct crypto_ablkcipher *tfm;
238 	struct crypto_hash *hash_tfm; /* Crypto context for generating
239 				       * the initialization vectors */
240 	unsigned char cipher[ECRYPTFS_MAX_CIPHER_NAME_SIZE];
241 	unsigned char key[ECRYPTFS_MAX_KEY_BYTES];
242 	unsigned char root_iv[ECRYPTFS_MAX_IV_BYTES];
243 	struct list_head keysig_list;
244 	struct mutex keysig_list_mutex;
245 	struct mutex cs_tfm_mutex;
246 	struct mutex cs_hash_tfm_mutex;
247 	struct mutex cs_mutex;
248 };
249 
250 /* inode private data. */
251 struct ecryptfs_inode_info {
252 	struct inode vfs_inode;
253 	struct inode *wii_inode;
254 	struct mutex lower_file_mutex;
255 	atomic_t lower_file_count;
256 	struct file *lower_file;
257 	struct ecryptfs_crypt_stat crypt_stat;
258 };
259 
260 /* dentry private data. Each dentry must keep track of a lower
261  * vfsmount too. */
262 struct ecryptfs_dentry_info {
263 	struct path lower_path;
264 	struct ecryptfs_crypt_stat *crypt_stat;
265 };
266 
267 /**
268  * ecryptfs_global_auth_tok - A key used to encrypt all new files under the mountpoint
269  * @flags: Status flags
270  * @mount_crypt_stat_list: These auth_toks hang off the mount-wide
271  *                         cryptographic context. Every time a new
272  *                         inode comes into existence, eCryptfs copies
273  *                         the auth_toks on that list to the set of
274  *                         auth_toks on the inode's crypt_stat
275  * @global_auth_tok_key: The key from the user's keyring for the sig
276  * @global_auth_tok: The key contents
277  * @sig: The key identifier
278  *
279  * ecryptfs_global_auth_tok structs refer to authentication token keys
280  * in the user keyring that apply to newly created files. A list of
281  * these objects hangs off of the mount_crypt_stat struct for any
282  * given eCryptfs mount. This struct maintains a reference to both the
283  * key contents and the key itself so that the key can be put on
284  * unmount.
285  */
286 struct ecryptfs_global_auth_tok {
287 #define ECRYPTFS_AUTH_TOK_INVALID 0x00000001
288 #define ECRYPTFS_AUTH_TOK_FNEK    0x00000002
289 	u32 flags;
290 	struct list_head mount_crypt_stat_list;
291 	struct key *global_auth_tok_key;
292 	unsigned char sig[ECRYPTFS_SIG_SIZE_HEX + 1];
293 };
294 
295 /**
296  * ecryptfs_key_tfm - Persistent key tfm
297  * @key_tfm: crypto API handle to the key
298  * @key_size: Key size in bytes
299  * @key_tfm_mutex: Mutex to ensure only one operation in eCryptfs is
300  *                 using the persistent TFM at any point in time
301  * @key_tfm_list: Handle to hang this off the module-wide TFM list
302  * @cipher_name: String name for the cipher for this TFM
303  *
304  * Typically, eCryptfs will use the same ciphers repeatedly throughout
305  * the course of its operations. In order to avoid unnecessarily
306  * destroying and initializing the same cipher repeatedly, eCryptfs
307  * keeps a list of crypto API contexts around to use when needed.
308  */
309 struct ecryptfs_key_tfm {
310 	struct crypto_blkcipher *key_tfm;
311 	size_t key_size;
312 	struct mutex key_tfm_mutex;
313 	struct list_head key_tfm_list;
314 	unsigned char cipher_name[ECRYPTFS_MAX_CIPHER_NAME_SIZE + 1];
315 };
316 
317 extern struct mutex key_tfm_list_mutex;
318 
319 /**
320  * This struct is to enable a mount-wide passphrase/salt combo. This
321  * is more or less a stopgap to provide similar functionality to other
322  * crypto filesystems like EncFS or CFS until full policy support is
323  * implemented in eCryptfs.
324  */
325 struct ecryptfs_mount_crypt_stat {
326 	/* Pointers to memory we do not own, do not free these */
327 #define ECRYPTFS_PLAINTEXT_PASSTHROUGH_ENABLED 0x00000001
328 #define ECRYPTFS_XATTR_METADATA_ENABLED        0x00000002
329 #define ECRYPTFS_ENCRYPTED_VIEW_ENABLED        0x00000004
330 #define ECRYPTFS_MOUNT_CRYPT_STAT_INITIALIZED  0x00000008
331 #define ECRYPTFS_GLOBAL_ENCRYPT_FILENAMES      0x00000010
332 #define ECRYPTFS_GLOBAL_ENCFN_USE_MOUNT_FNEK   0x00000020
333 #define ECRYPTFS_GLOBAL_ENCFN_USE_FEK          0x00000040
334 #define ECRYPTFS_GLOBAL_MOUNT_AUTH_TOK_ONLY    0x00000080
335 	u32 flags;
336 	struct list_head global_auth_tok_list;
337 	struct mutex global_auth_tok_list_mutex;
338 	size_t global_default_cipher_key_size;
339 	size_t global_default_fn_cipher_key_bytes;
340 	unsigned char global_default_cipher_name[ECRYPTFS_MAX_CIPHER_NAME_SIZE
341 						 + 1];
342 	unsigned char global_default_fn_cipher_name[
343 		ECRYPTFS_MAX_CIPHER_NAME_SIZE + 1];
344 	char global_default_fnek_sig[ECRYPTFS_SIG_SIZE_HEX + 1];
345 };
346 
347 /* superblock private data. */
348 struct ecryptfs_sb_info {
349 	struct super_block *wsi_sb;
350 	struct ecryptfs_mount_crypt_stat mount_crypt_stat;
351 	struct backing_dev_info bdi;
352 };
353 
354 /* file private data. */
355 struct ecryptfs_file_info {
356 	struct file *wfi_file;
357 	struct ecryptfs_crypt_stat *crypt_stat;
358 };
359 
360 /* auth_tok <=> encrypted_session_key mappings */
361 struct ecryptfs_auth_tok_list_item {
362 	unsigned char encrypted_session_key[ECRYPTFS_MAX_KEY_BYTES];
363 	struct list_head list;
364 	struct ecryptfs_auth_tok auth_tok;
365 };
366 
367 struct ecryptfs_message {
368 	/* Can never be greater than ecryptfs_message_buf_len */
369 	/* Used to find the parent msg_ctx */
370 	/* Inherits from msg_ctx->index */
371 	u32 index;
372 	u32 data_len;
373 	u8 data[];
374 };
375 
376 struct ecryptfs_msg_ctx {
377 #define ECRYPTFS_MSG_CTX_STATE_FREE     0x01
378 #define ECRYPTFS_MSG_CTX_STATE_PENDING  0x02
379 #define ECRYPTFS_MSG_CTX_STATE_DONE     0x03
380 #define ECRYPTFS_MSG_CTX_STATE_NO_REPLY 0x04
381 	u8 state;
382 #define ECRYPTFS_MSG_HELO 100
383 #define ECRYPTFS_MSG_QUIT 101
384 #define ECRYPTFS_MSG_REQUEST 102
385 #define ECRYPTFS_MSG_RESPONSE 103
386 	u8 type;
387 	u32 index;
388 	/* Counter converts to a sequence number. Each message sent
389 	 * out for which we expect a response has an associated
390 	 * sequence number. The response must have the same sequence
391 	 * number as the counter for the msg_stc for the message to be
392 	 * valid. */
393 	u32 counter;
394 	size_t msg_size;
395 	struct ecryptfs_message *msg;
396 	struct task_struct *task;
397 	struct list_head node;
398 	struct list_head daemon_out_list;
399 	struct mutex mux;
400 };
401 
402 struct ecryptfs_daemon {
403 #define ECRYPTFS_DAEMON_IN_READ      0x00000001
404 #define ECRYPTFS_DAEMON_IN_POLL      0x00000002
405 #define ECRYPTFS_DAEMON_ZOMBIE       0x00000004
406 #define ECRYPTFS_DAEMON_MISCDEV_OPEN 0x00000008
407 	u32 flags;
408 	u32 num_queued_msg_ctx;
409 	struct file *file;
410 	struct mutex mux;
411 	struct list_head msg_ctx_out_queue;
412 	wait_queue_head_t wait;
413 	struct hlist_node euid_chain;
414 };
415 
416 #ifdef CONFIG_ECRYPT_FS_MESSAGING
417 extern struct mutex ecryptfs_daemon_hash_mux;
418 #endif
419 
420 static inline size_t
421 ecryptfs_lower_header_size(struct ecryptfs_crypt_stat *crypt_stat)
422 {
423 	if (crypt_stat->flags & ECRYPTFS_METADATA_IN_XATTR)
424 		return 0;
425 	return crypt_stat->metadata_size;
426 }
427 
428 static inline struct ecryptfs_file_info *
429 ecryptfs_file_to_private(struct file *file)
430 {
431 	return file->private_data;
432 }
433 
434 static inline void
435 ecryptfs_set_file_private(struct file *file,
436 			  struct ecryptfs_file_info *file_info)
437 {
438 	file->private_data = file_info;
439 }
440 
441 static inline struct file *ecryptfs_file_to_lower(struct file *file)
442 {
443 	return ((struct ecryptfs_file_info *)file->private_data)->wfi_file;
444 }
445 
446 static inline void
447 ecryptfs_set_file_lower(struct file *file, struct file *lower_file)
448 {
449 	((struct ecryptfs_file_info *)file->private_data)->wfi_file =
450 		lower_file;
451 }
452 
453 static inline struct ecryptfs_inode_info *
454 ecryptfs_inode_to_private(struct inode *inode)
455 {
456 	return container_of(inode, struct ecryptfs_inode_info, vfs_inode);
457 }
458 
459 static inline struct inode *ecryptfs_inode_to_lower(struct inode *inode)
460 {
461 	return ecryptfs_inode_to_private(inode)->wii_inode;
462 }
463 
464 static inline void
465 ecryptfs_set_inode_lower(struct inode *inode, struct inode *lower_inode)
466 {
467 	ecryptfs_inode_to_private(inode)->wii_inode = lower_inode;
468 }
469 
470 static inline struct ecryptfs_sb_info *
471 ecryptfs_superblock_to_private(struct super_block *sb)
472 {
473 	return (struct ecryptfs_sb_info *)sb->s_fs_info;
474 }
475 
476 static inline void
477 ecryptfs_set_superblock_private(struct super_block *sb,
478 				struct ecryptfs_sb_info *sb_info)
479 {
480 	sb->s_fs_info = sb_info;
481 }
482 
483 static inline struct super_block *
484 ecryptfs_superblock_to_lower(struct super_block *sb)
485 {
486 	return ((struct ecryptfs_sb_info *)sb->s_fs_info)->wsi_sb;
487 }
488 
489 static inline void
490 ecryptfs_set_superblock_lower(struct super_block *sb,
491 			      struct super_block *lower_sb)
492 {
493 	((struct ecryptfs_sb_info *)sb->s_fs_info)->wsi_sb = lower_sb;
494 }
495 
496 static inline struct ecryptfs_dentry_info *
497 ecryptfs_dentry_to_private(struct dentry *dentry)
498 {
499 	return (struct ecryptfs_dentry_info *)dentry->d_fsdata;
500 }
501 
502 static inline void
503 ecryptfs_set_dentry_private(struct dentry *dentry,
504 			    struct ecryptfs_dentry_info *dentry_info)
505 {
506 	dentry->d_fsdata = dentry_info;
507 }
508 
509 static inline struct dentry *
510 ecryptfs_dentry_to_lower(struct dentry *dentry)
511 {
512 	return ((struct ecryptfs_dentry_info *)dentry->d_fsdata)->lower_path.dentry;
513 }
514 
515 static inline void
516 ecryptfs_set_dentry_lower(struct dentry *dentry, struct dentry *lower_dentry)
517 {
518 	((struct ecryptfs_dentry_info *)dentry->d_fsdata)->lower_path.dentry =
519 		lower_dentry;
520 }
521 
522 static inline struct vfsmount *
523 ecryptfs_dentry_to_lower_mnt(struct dentry *dentry)
524 {
525 	return ((struct ecryptfs_dentry_info *)dentry->d_fsdata)->lower_path.mnt;
526 }
527 
528 static inline struct path *
529 ecryptfs_dentry_to_lower_path(struct dentry *dentry)
530 {
531 	return &((struct ecryptfs_dentry_info *)dentry->d_fsdata)->lower_path;
532 }
533 
534 static inline void
535 ecryptfs_set_dentry_lower_mnt(struct dentry *dentry, struct vfsmount *lower_mnt)
536 {
537 	((struct ecryptfs_dentry_info *)dentry->d_fsdata)->lower_path.mnt =
538 		lower_mnt;
539 }
540 
541 #define ecryptfs_printk(type, fmt, arg...) \
542         __ecryptfs_printk(type "%s: " fmt, __func__, ## arg);
543 __printf(1, 2)
544 void __ecryptfs_printk(const char *fmt, ...);
545 
546 extern const struct file_operations ecryptfs_main_fops;
547 extern const struct file_operations ecryptfs_dir_fops;
548 extern const struct inode_operations ecryptfs_main_iops;
549 extern const struct inode_operations ecryptfs_dir_iops;
550 extern const struct inode_operations ecryptfs_symlink_iops;
551 extern const struct super_operations ecryptfs_sops;
552 extern const struct dentry_operations ecryptfs_dops;
553 extern const struct address_space_operations ecryptfs_aops;
554 extern int ecryptfs_verbosity;
555 extern unsigned int ecryptfs_message_buf_len;
556 extern signed long ecryptfs_message_wait_timeout;
557 extern unsigned int ecryptfs_number_of_users;
558 
559 extern struct kmem_cache *ecryptfs_auth_tok_list_item_cache;
560 extern struct kmem_cache *ecryptfs_file_info_cache;
561 extern struct kmem_cache *ecryptfs_dentry_info_cache;
562 extern struct kmem_cache *ecryptfs_inode_info_cache;
563 extern struct kmem_cache *ecryptfs_sb_info_cache;
564 extern struct kmem_cache *ecryptfs_header_cache;
565 extern struct kmem_cache *ecryptfs_xattr_cache;
566 extern struct kmem_cache *ecryptfs_key_record_cache;
567 extern struct kmem_cache *ecryptfs_key_sig_cache;
568 extern struct kmem_cache *ecryptfs_global_auth_tok_cache;
569 extern struct kmem_cache *ecryptfs_key_tfm_cache;
570 
571 struct inode *ecryptfs_get_inode(struct inode *lower_inode,
572 				 struct super_block *sb);
573 void ecryptfs_i_size_init(const char *page_virt, struct inode *inode);
574 int ecryptfs_initialize_file(struct dentry *ecryptfs_dentry,
575 			     struct inode *ecryptfs_inode);
576 int ecryptfs_decode_and_decrypt_filename(char **decrypted_name,
577 					 size_t *decrypted_name_size,
578 					 struct dentry *ecryptfs_dentry,
579 					 const char *name, size_t name_size);
580 int ecryptfs_fill_zeros(struct file *file, loff_t new_length);
581 int ecryptfs_encrypt_and_encode_filename(
582 	char **encoded_name,
583 	size_t *encoded_name_size,
584 	struct ecryptfs_crypt_stat *crypt_stat,
585 	struct ecryptfs_mount_crypt_stat *mount_crypt_stat,
586 	const char *name, size_t name_size);
587 struct dentry *ecryptfs_lower_dentry(struct dentry *this_dentry);
588 void ecryptfs_dump_hex(char *data, int bytes);
589 int virt_to_scatterlist(const void *addr, int size, struct scatterlist *sg,
590 			int sg_size);
591 int ecryptfs_compute_root_iv(struct ecryptfs_crypt_stat *crypt_stat);
592 void ecryptfs_rotate_iv(unsigned char *iv);
593 void ecryptfs_init_crypt_stat(struct ecryptfs_crypt_stat *crypt_stat);
594 void ecryptfs_destroy_crypt_stat(struct ecryptfs_crypt_stat *crypt_stat);
595 void ecryptfs_destroy_mount_crypt_stat(
596 	struct ecryptfs_mount_crypt_stat *mount_crypt_stat);
597 int ecryptfs_init_crypt_ctx(struct ecryptfs_crypt_stat *crypt_stat);
598 int ecryptfs_write_inode_size_to_metadata(struct inode *ecryptfs_inode);
599 int ecryptfs_encrypt_page(struct page *page);
600 int ecryptfs_decrypt_page(struct page *page);
601 int ecryptfs_write_metadata(struct dentry *ecryptfs_dentry,
602 			    struct inode *ecryptfs_inode);
603 int ecryptfs_read_metadata(struct dentry *ecryptfs_dentry);
604 int ecryptfs_new_file_context(struct inode *ecryptfs_inode);
605 void ecryptfs_write_crypt_stat_flags(char *page_virt,
606 				     struct ecryptfs_crypt_stat *crypt_stat,
607 				     size_t *written);
608 int ecryptfs_read_and_validate_header_region(struct inode *inode);
609 int ecryptfs_read_and_validate_xattr_region(struct dentry *dentry,
610 					    struct inode *inode);
611 u8 ecryptfs_code_for_cipher_string(char *cipher_name, size_t key_bytes);
612 int ecryptfs_cipher_code_to_string(char *str, u8 cipher_code);
613 void ecryptfs_set_default_sizes(struct ecryptfs_crypt_stat *crypt_stat);
614 int ecryptfs_generate_key_packet_set(char *dest_base,
615 				     struct ecryptfs_crypt_stat *crypt_stat,
616 				     struct dentry *ecryptfs_dentry,
617 				     size_t *len, size_t max);
618 int
619 ecryptfs_parse_packet_set(struct ecryptfs_crypt_stat *crypt_stat,
620 			  unsigned char *src, struct dentry *ecryptfs_dentry);
621 int ecryptfs_truncate(struct dentry *dentry, loff_t new_length);
622 ssize_t
623 ecryptfs_getxattr_lower(struct dentry *lower_dentry, const char *name,
624 			void *value, size_t size);
625 int
626 ecryptfs_setxattr(struct dentry *dentry, const char *name, const void *value,
627 		  size_t size, int flags);
628 int ecryptfs_read_xattr_region(char *page_virt, struct inode *ecryptfs_inode);
629 #ifdef CONFIG_ECRYPT_FS_MESSAGING
630 int ecryptfs_process_response(struct ecryptfs_daemon *daemon,
631 			      struct ecryptfs_message *msg, u32 seq);
632 int ecryptfs_send_message(char *data, int data_len,
633 			  struct ecryptfs_msg_ctx **msg_ctx);
634 int ecryptfs_wait_for_response(struct ecryptfs_msg_ctx *msg_ctx,
635 			       struct ecryptfs_message **emsg);
636 int ecryptfs_init_messaging(void);
637 void ecryptfs_release_messaging(void);
638 #else
639 static inline int ecryptfs_init_messaging(void)
640 {
641 	return 0;
642 }
643 static inline void ecryptfs_release_messaging(void)
644 { }
645 static inline int ecryptfs_send_message(char *data, int data_len,
646 					struct ecryptfs_msg_ctx **msg_ctx)
647 {
648 	return -ENOTCONN;
649 }
650 static inline int ecryptfs_wait_for_response(struct ecryptfs_msg_ctx *msg_ctx,
651 					     struct ecryptfs_message **emsg)
652 {
653 	return -ENOMSG;
654 }
655 #endif
656 
657 void
658 ecryptfs_write_header_metadata(char *virt,
659 			       struct ecryptfs_crypt_stat *crypt_stat,
660 			       size_t *written);
661 int ecryptfs_add_keysig(struct ecryptfs_crypt_stat *crypt_stat, char *sig);
662 int
663 ecryptfs_add_global_auth_tok(struct ecryptfs_mount_crypt_stat *mount_crypt_stat,
664 			   char *sig, u32 global_auth_tok_flags);
665 int ecryptfs_get_global_auth_tok_for_sig(
666 	struct ecryptfs_global_auth_tok **global_auth_tok,
667 	struct ecryptfs_mount_crypt_stat *mount_crypt_stat, char *sig);
668 int
669 ecryptfs_add_new_key_tfm(struct ecryptfs_key_tfm **key_tfm, char *cipher_name,
670 			 size_t key_size);
671 int ecryptfs_init_crypto(void);
672 int ecryptfs_destroy_crypto(void);
673 int ecryptfs_tfm_exists(char *cipher_name, struct ecryptfs_key_tfm **key_tfm);
674 int ecryptfs_get_tfm_and_mutex_for_cipher_name(struct crypto_blkcipher **tfm,
675 					       struct mutex **tfm_mutex,
676 					       char *cipher_name);
677 int ecryptfs_keyring_auth_tok_for_sig(struct key **auth_tok_key,
678 				      struct ecryptfs_auth_tok **auth_tok,
679 				      char *sig);
680 int ecryptfs_write_lower(struct inode *ecryptfs_inode, char *data,
681 			 loff_t offset, size_t size);
682 int ecryptfs_write_lower_page_segment(struct inode *ecryptfs_inode,
683 				      struct page *page_for_lower,
684 				      size_t offset_in_page, size_t size);
685 int ecryptfs_write(struct inode *inode, char *data, loff_t offset, size_t size);
686 int ecryptfs_read_lower(char *data, loff_t offset, size_t size,
687 			struct inode *ecryptfs_inode);
688 int ecryptfs_read_lower_page_segment(struct page *page_for_ecryptfs,
689 				     pgoff_t page_index,
690 				     size_t offset_in_page, size_t size,
691 				     struct inode *ecryptfs_inode);
692 struct page *ecryptfs_get_locked_page(struct inode *inode, loff_t index);
693 int ecryptfs_parse_packet_length(unsigned char *data, size_t *size,
694 				 size_t *length_size);
695 int ecryptfs_write_packet_length(char *dest, size_t size,
696 				 size_t *packet_size_length);
697 #ifdef CONFIG_ECRYPT_FS_MESSAGING
698 int ecryptfs_init_ecryptfs_miscdev(void);
699 void ecryptfs_destroy_ecryptfs_miscdev(void);
700 int ecryptfs_send_miscdev(char *data, size_t data_size,
701 			  struct ecryptfs_msg_ctx *msg_ctx, u8 msg_type,
702 			  u16 msg_flags, struct ecryptfs_daemon *daemon);
703 void ecryptfs_msg_ctx_alloc_to_free(struct ecryptfs_msg_ctx *msg_ctx);
704 int
705 ecryptfs_spawn_daemon(struct ecryptfs_daemon **daemon, struct file *file);
706 int ecryptfs_exorcise_daemon(struct ecryptfs_daemon *daemon);
707 int ecryptfs_find_daemon_by_euid(struct ecryptfs_daemon **daemon);
708 #endif
709 int ecryptfs_init_kthread(void);
710 void ecryptfs_destroy_kthread(void);
711 int ecryptfs_privileged_open(struct file **lower_file,
712 			     struct dentry *lower_dentry,
713 			     struct vfsmount *lower_mnt,
714 			     const struct cred *cred);
715 int ecryptfs_get_lower_file(struct dentry *dentry, struct inode *inode);
716 void ecryptfs_put_lower_file(struct inode *inode);
717 int
718 ecryptfs_write_tag_70_packet(char *dest, size_t *remaining_bytes,
719 			     size_t *packet_size,
720 			     struct ecryptfs_mount_crypt_stat *mount_crypt_stat,
721 			     char *filename, size_t filename_size);
722 int
723 ecryptfs_parse_tag_70_packet(char **filename, size_t *filename_size,
724 			     size_t *packet_size,
725 			     struct ecryptfs_mount_crypt_stat *mount_crypt_stat,
726 			     char *data, size_t max_packet_size);
727 int ecryptfs_set_f_namelen(long *namelen, long lower_namelen,
728 			   struct ecryptfs_mount_crypt_stat *mount_crypt_stat);
729 int ecryptfs_derive_iv(char *iv, struct ecryptfs_crypt_stat *crypt_stat,
730 		       loff_t offset);
731 
732 #endif /* #ifndef ECRYPTFS_KERNEL_H */
733