xref: /linux/fs/ecryptfs/ecryptfs_kernel.h (revision e9f0878c4b2004ac19581274c1ae4c61ae3ca70e)
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 <crypto/skcipher.h>
32 #include <keys/user-type.h>
33 #include <keys/encrypted-type.h>
34 #include <linux/kernel.h>
35 #include <linux/fs.h>
36 #include <linux/fs_stack.h>
37 #include <linux/namei.h>
38 #include <linux/scatterlist.h>
39 #include <linux/hash.h>
40 #include <linux/nsproxy.h>
41 #include <linux/backing-dev.h>
42 #include <linux/ecryptfs.h>
43 
44 #define ECRYPTFS_DEFAULT_IV_BYTES 16
45 #define ECRYPTFS_DEFAULT_EXTENT_SIZE 4096
46 #define ECRYPTFS_MINIMUM_HEADER_EXTENT_SIZE 8192
47 #define ECRYPTFS_DEFAULT_MSG_CTX_ELEMS 32
48 #define ECRYPTFS_DEFAULT_SEND_TIMEOUT HZ
49 #define ECRYPTFS_MAX_MSG_CTX_TTL (HZ*3)
50 #define ECRYPTFS_DEFAULT_NUM_USERS 4
51 #define ECRYPTFS_MAX_NUM_USERS 32768
52 #define ECRYPTFS_XATTR_NAME "user.ecryptfs"
53 
54 void ecryptfs_dump_auth_tok(struct ecryptfs_auth_tok *auth_tok);
55 static inline void
56 ecryptfs_to_hex(char *dst, char *src, size_t src_size)
57 {
58 	char *end = bin2hex(dst, src, src_size);
59 	*end = '\0';
60 }
61 
62 extern void ecryptfs_from_hex(char *dst, char *src, int dst_size);
63 
64 struct ecryptfs_key_record {
65 	unsigned char type;
66 	size_t enc_key_size;
67 	unsigned char sig[ECRYPTFS_SIG_SIZE];
68 	unsigned char enc_key[ECRYPTFS_MAX_ENCRYPTED_KEY_BYTES];
69 };
70 
71 struct ecryptfs_auth_tok_list {
72 	struct ecryptfs_auth_tok *auth_tok;
73 	struct list_head list;
74 };
75 
76 struct ecryptfs_crypt_stat;
77 struct ecryptfs_mount_crypt_stat;
78 
79 struct ecryptfs_page_crypt_context {
80 	struct page *page;
81 #define ECRYPTFS_PREPARE_COMMIT_MODE 0
82 #define ECRYPTFS_WRITEPAGE_MODE      1
83 	unsigned int mode;
84 	union {
85 		struct file *lower_file;
86 		struct writeback_control *wbc;
87 	} param;
88 };
89 
90 #if defined(CONFIG_ENCRYPTED_KEYS) || defined(CONFIG_ENCRYPTED_KEYS_MODULE)
91 static inline struct ecryptfs_auth_tok *
92 ecryptfs_get_encrypted_key_payload_data(struct key *key)
93 {
94 	struct encrypted_key_payload *payload;
95 
96 	if (key->type != &key_type_encrypted)
97 		return NULL;
98 
99 	payload = key->payload.data[0];
100 	if (!payload)
101 		return ERR_PTR(-EKEYREVOKED);
102 
103 	return (struct ecryptfs_auth_tok *)payload->payload_data;
104 }
105 
106 static inline struct key *ecryptfs_get_encrypted_key(char *sig)
107 {
108 	return request_key(&key_type_encrypted, sig, NULL);
109 }
110 
111 #else
112 static inline struct ecryptfs_auth_tok *
113 ecryptfs_get_encrypted_key_payload_data(struct key *key)
114 {
115 	return NULL;
116 }
117 
118 static inline struct key *ecryptfs_get_encrypted_key(char *sig)
119 {
120 	return ERR_PTR(-ENOKEY);
121 }
122 
123 #endif /* CONFIG_ENCRYPTED_KEYS */
124 
125 static inline struct ecryptfs_auth_tok *
126 ecryptfs_get_key_payload_data(struct key *key)
127 {
128 	struct ecryptfs_auth_tok *auth_tok;
129 	struct user_key_payload *ukp;
130 
131 	auth_tok = ecryptfs_get_encrypted_key_payload_data(key);
132 	if (auth_tok)
133 		return auth_tok;
134 
135 	ukp = user_key_payload_locked(key);
136 	if (!ukp)
137 		return ERR_PTR(-EKEYREVOKED);
138 
139 	return (struct ecryptfs_auth_tok *)ukp->data;
140 }
141 
142 #define ECRYPTFS_MAX_KEYSET_SIZE 1024
143 #define ECRYPTFS_MAX_CIPHER_NAME_SIZE 31
144 #define ECRYPTFS_MAX_NUM_ENC_KEYS 64
145 #define ECRYPTFS_MAX_IV_BYTES 16	/* 128 bits */
146 #define ECRYPTFS_SALT_BYTES 2
147 #define MAGIC_ECRYPTFS_MARKER 0x3c81b7f5
148 #define MAGIC_ECRYPTFS_MARKER_SIZE_BYTES 8	/* 4*2 */
149 #define ECRYPTFS_FILE_SIZE_BYTES (sizeof(u64))
150 #define ECRYPTFS_SIZE_AND_MARKER_BYTES (ECRYPTFS_FILE_SIZE_BYTES \
151 					+ MAGIC_ECRYPTFS_MARKER_SIZE_BYTES)
152 #define ECRYPTFS_DEFAULT_CIPHER "aes"
153 #define ECRYPTFS_DEFAULT_KEY_BYTES 16
154 #define ECRYPTFS_DEFAULT_HASH "md5"
155 #define ECRYPTFS_TAG_70_DIGEST ECRYPTFS_DEFAULT_HASH
156 #define ECRYPTFS_TAG_1_PACKET_TYPE 0x01
157 #define ECRYPTFS_TAG_3_PACKET_TYPE 0x8C
158 #define ECRYPTFS_TAG_11_PACKET_TYPE 0xED
159 #define ECRYPTFS_TAG_64_PACKET_TYPE 0x40
160 #define ECRYPTFS_TAG_65_PACKET_TYPE 0x41
161 #define ECRYPTFS_TAG_66_PACKET_TYPE 0x42
162 #define ECRYPTFS_TAG_67_PACKET_TYPE 0x43
163 #define ECRYPTFS_TAG_70_PACKET_TYPE 0x46 /* FNEK-encrypted filename
164 					  * as dentry name */
165 #define ECRYPTFS_TAG_71_PACKET_TYPE 0x47 /* FNEK-encrypted filename in
166 					  * metadata */
167 #define ECRYPTFS_TAG_72_PACKET_TYPE 0x48 /* FEK-encrypted filename as
168 					  * dentry name */
169 #define ECRYPTFS_TAG_73_PACKET_TYPE 0x49 /* FEK-encrypted filename as
170 					  * metadata */
171 #define ECRYPTFS_MIN_PKT_LEN_SIZE 1 /* Min size to specify packet length */
172 #define ECRYPTFS_MAX_PKT_LEN_SIZE 2 /* Pass at least this many bytes to
173 				     * ecryptfs_parse_packet_length() and
174 				     * ecryptfs_write_packet_length()
175 				     */
176 /* Constraint: ECRYPTFS_FILENAME_MIN_RANDOM_PREPEND_BYTES >=
177  * ECRYPTFS_MAX_IV_BYTES */
178 #define ECRYPTFS_FILENAME_MIN_RANDOM_PREPEND_BYTES 16
179 #define ECRYPTFS_NON_NULL 0x42 /* A reasonable substitute for NULL */
180 #define MD5_DIGEST_SIZE 16
181 #define ECRYPTFS_TAG_70_DIGEST_SIZE MD5_DIGEST_SIZE
182 #define ECRYPTFS_TAG_70_MIN_METADATA_SIZE (1 + ECRYPTFS_MIN_PKT_LEN_SIZE \
183 					   + ECRYPTFS_SIG_SIZE + 1 + 1)
184 #define ECRYPTFS_TAG_70_MAX_METADATA_SIZE (1 + ECRYPTFS_MAX_PKT_LEN_SIZE \
185 					   + ECRYPTFS_SIG_SIZE + 1 + 1)
186 #define ECRYPTFS_FEK_ENCRYPTED_FILENAME_PREFIX "ECRYPTFS_FEK_ENCRYPTED."
187 #define ECRYPTFS_FEK_ENCRYPTED_FILENAME_PREFIX_SIZE 23
188 #define ECRYPTFS_FNEK_ENCRYPTED_FILENAME_PREFIX "ECRYPTFS_FNEK_ENCRYPTED."
189 #define ECRYPTFS_FNEK_ENCRYPTED_FILENAME_PREFIX_SIZE 24
190 #define ECRYPTFS_ENCRYPTED_DENTRY_NAME_LEN (18 + 1 + 4 + 1 + 32)
191 
192 #ifdef CONFIG_ECRYPT_FS_MESSAGING
193 # define ECRYPTFS_VERSIONING_MASK_MESSAGING (ECRYPTFS_VERSIONING_DEVMISC \
194 					     | ECRYPTFS_VERSIONING_PUBKEY)
195 #else
196 # define ECRYPTFS_VERSIONING_MASK_MESSAGING 0
197 #endif
198 
199 #define ECRYPTFS_VERSIONING_MASK (ECRYPTFS_VERSIONING_PASSPHRASE \
200 				  | ECRYPTFS_VERSIONING_PLAINTEXT_PASSTHROUGH \
201 				  | ECRYPTFS_VERSIONING_XATTR \
202 				  | ECRYPTFS_VERSIONING_MULTKEY \
203 				  | ECRYPTFS_VERSIONING_MASK_MESSAGING \
204 				  | ECRYPTFS_VERSIONING_FILENAME_ENCRYPTION)
205 struct ecryptfs_key_sig {
206 	struct list_head crypt_stat_list;
207 	char keysig[ECRYPTFS_SIG_SIZE_HEX + 1];
208 };
209 
210 struct ecryptfs_filename {
211 	struct list_head crypt_stat_list;
212 #define ECRYPTFS_FILENAME_CONTAINS_DECRYPTED 0x00000001
213 	u32 flags;
214 	u32 seq_no;
215 	char *filename;
216 	char *encrypted_filename;
217 	size_t filename_size;
218 	size_t encrypted_filename_size;
219 	char fnek_sig[ECRYPTFS_SIG_SIZE_HEX];
220 	char dentry_name[ECRYPTFS_ENCRYPTED_DENTRY_NAME_LEN + 1];
221 };
222 
223 /**
224  * This is the primary struct associated with each encrypted file.
225  *
226  * TODO: cache align/pack?
227  */
228 struct ecryptfs_crypt_stat {
229 #define ECRYPTFS_STRUCT_INITIALIZED   0x00000001
230 #define ECRYPTFS_POLICY_APPLIED       0x00000002
231 #define ECRYPTFS_ENCRYPTED            0x00000004
232 #define ECRYPTFS_SECURITY_WARNING     0x00000008
233 #define ECRYPTFS_ENABLE_HMAC          0x00000010
234 #define ECRYPTFS_ENCRYPT_IV_PAGES     0x00000020
235 #define ECRYPTFS_KEY_VALID            0x00000040
236 #define ECRYPTFS_METADATA_IN_XATTR    0x00000080
237 #define ECRYPTFS_VIEW_AS_ENCRYPTED    0x00000100
238 #define ECRYPTFS_KEY_SET              0x00000200
239 #define ECRYPTFS_ENCRYPT_FILENAMES    0x00000400
240 #define ECRYPTFS_ENCFN_USE_MOUNT_FNEK 0x00000800
241 #define ECRYPTFS_ENCFN_USE_FEK        0x00001000
242 #define ECRYPTFS_UNLINK_SIGS          0x00002000
243 #define ECRYPTFS_I_SIZE_INITIALIZED   0x00004000
244 	u32 flags;
245 	unsigned int file_version;
246 	size_t iv_bytes;
247 	size_t metadata_size;
248 	size_t extent_size; /* Data extent size; default is 4096 */
249 	size_t key_size;
250 	size_t extent_shift;
251 	unsigned int extent_mask;
252 	struct ecryptfs_mount_crypt_stat *mount_crypt_stat;
253 	struct crypto_skcipher *tfm;
254 	struct crypto_shash *hash_tfm; /* Crypto context for generating
255 					* the initialization vectors */
256 	unsigned char cipher[ECRYPTFS_MAX_CIPHER_NAME_SIZE + 1];
257 	unsigned char key[ECRYPTFS_MAX_KEY_BYTES];
258 	unsigned char root_iv[ECRYPTFS_MAX_IV_BYTES];
259 	struct list_head keysig_list;
260 	struct mutex keysig_list_mutex;
261 	struct mutex cs_tfm_mutex;
262 	struct mutex cs_mutex;
263 };
264 
265 /* inode private data. */
266 struct ecryptfs_inode_info {
267 	struct inode vfs_inode;
268 	struct inode *wii_inode;
269 	struct mutex lower_file_mutex;
270 	atomic_t lower_file_count;
271 	struct file *lower_file;
272 	struct ecryptfs_crypt_stat crypt_stat;
273 };
274 
275 /* dentry private data. Each dentry must keep track of a lower
276  * vfsmount too. */
277 struct ecryptfs_dentry_info {
278 	struct path lower_path;
279 	union {
280 		struct ecryptfs_crypt_stat *crypt_stat;
281 		struct rcu_head rcu;
282 	};
283 };
284 
285 /**
286  * ecryptfs_global_auth_tok - A key used to encrypt all new files under the mountpoint
287  * @flags: Status flags
288  * @mount_crypt_stat_list: These auth_toks hang off the mount-wide
289  *                         cryptographic context. Every time a new
290  *                         inode comes into existence, eCryptfs copies
291  *                         the auth_toks on that list to the set of
292  *                         auth_toks on the inode's crypt_stat
293  * @global_auth_tok_key: The key from the user's keyring for the sig
294  * @global_auth_tok: The key contents
295  * @sig: The key identifier
296  *
297  * ecryptfs_global_auth_tok structs refer to authentication token keys
298  * in the user keyring that apply to newly created files. A list of
299  * these objects hangs off of the mount_crypt_stat struct for any
300  * given eCryptfs mount. This struct maintains a reference to both the
301  * key contents and the key itself so that the key can be put on
302  * unmount.
303  */
304 struct ecryptfs_global_auth_tok {
305 #define ECRYPTFS_AUTH_TOK_INVALID 0x00000001
306 #define ECRYPTFS_AUTH_TOK_FNEK    0x00000002
307 	u32 flags;
308 	struct list_head mount_crypt_stat_list;
309 	struct key *global_auth_tok_key;
310 	unsigned char sig[ECRYPTFS_SIG_SIZE_HEX + 1];
311 };
312 
313 /**
314  * ecryptfs_key_tfm - Persistent key tfm
315  * @key_tfm: crypto API handle to the key
316  * @key_size: Key size in bytes
317  * @key_tfm_mutex: Mutex to ensure only one operation in eCryptfs is
318  *                 using the persistent TFM at any point in time
319  * @key_tfm_list: Handle to hang this off the module-wide TFM list
320  * @cipher_name: String name for the cipher for this TFM
321  *
322  * Typically, eCryptfs will use the same ciphers repeatedly throughout
323  * the course of its operations. In order to avoid unnecessarily
324  * destroying and initializing the same cipher repeatedly, eCryptfs
325  * keeps a list of crypto API contexts around to use when needed.
326  */
327 struct ecryptfs_key_tfm {
328 	struct crypto_skcipher *key_tfm;
329 	size_t key_size;
330 	struct mutex key_tfm_mutex;
331 	struct list_head key_tfm_list;
332 	unsigned char cipher_name[ECRYPTFS_MAX_CIPHER_NAME_SIZE + 1];
333 };
334 
335 extern struct mutex key_tfm_list_mutex;
336 
337 /**
338  * This struct is to enable a mount-wide passphrase/salt combo. This
339  * is more or less a stopgap to provide similar functionality to other
340  * crypto filesystems like EncFS or CFS until full policy support is
341  * implemented in eCryptfs.
342  */
343 struct ecryptfs_mount_crypt_stat {
344 	/* Pointers to memory we do not own, do not free these */
345 #define ECRYPTFS_PLAINTEXT_PASSTHROUGH_ENABLED 0x00000001
346 #define ECRYPTFS_XATTR_METADATA_ENABLED        0x00000002
347 #define ECRYPTFS_ENCRYPTED_VIEW_ENABLED        0x00000004
348 #define ECRYPTFS_MOUNT_CRYPT_STAT_INITIALIZED  0x00000008
349 #define ECRYPTFS_GLOBAL_ENCRYPT_FILENAMES      0x00000010
350 #define ECRYPTFS_GLOBAL_ENCFN_USE_MOUNT_FNEK   0x00000020
351 #define ECRYPTFS_GLOBAL_ENCFN_USE_FEK          0x00000040
352 #define ECRYPTFS_GLOBAL_MOUNT_AUTH_TOK_ONLY    0x00000080
353 	u32 flags;
354 	struct list_head global_auth_tok_list;
355 	struct mutex global_auth_tok_list_mutex;
356 	size_t global_default_cipher_key_size;
357 	size_t global_default_fn_cipher_key_bytes;
358 	unsigned char global_default_cipher_name[ECRYPTFS_MAX_CIPHER_NAME_SIZE
359 						 + 1];
360 	unsigned char global_default_fn_cipher_name[
361 		ECRYPTFS_MAX_CIPHER_NAME_SIZE + 1];
362 	char global_default_fnek_sig[ECRYPTFS_SIG_SIZE_HEX + 1];
363 };
364 
365 /* superblock private data. */
366 struct ecryptfs_sb_info {
367 	struct super_block *wsi_sb;
368 	struct ecryptfs_mount_crypt_stat mount_crypt_stat;
369 };
370 
371 /* file private data. */
372 struct ecryptfs_file_info {
373 	struct file *wfi_file;
374 	struct ecryptfs_crypt_stat *crypt_stat;
375 };
376 
377 /* auth_tok <=> encrypted_session_key mappings */
378 struct ecryptfs_auth_tok_list_item {
379 	unsigned char encrypted_session_key[ECRYPTFS_MAX_KEY_BYTES];
380 	struct list_head list;
381 	struct ecryptfs_auth_tok auth_tok;
382 };
383 
384 struct ecryptfs_message {
385 	/* Can never be greater than ecryptfs_message_buf_len */
386 	/* Used to find the parent msg_ctx */
387 	/* Inherits from msg_ctx->index */
388 	u32 index;
389 	u32 data_len;
390 	u8 data[];
391 };
392 
393 struct ecryptfs_msg_ctx {
394 #define ECRYPTFS_MSG_CTX_STATE_FREE     0x01
395 #define ECRYPTFS_MSG_CTX_STATE_PENDING  0x02
396 #define ECRYPTFS_MSG_CTX_STATE_DONE     0x03
397 #define ECRYPTFS_MSG_CTX_STATE_NO_REPLY 0x04
398 	u8 state;
399 #define ECRYPTFS_MSG_HELO 100
400 #define ECRYPTFS_MSG_QUIT 101
401 #define ECRYPTFS_MSG_REQUEST 102
402 #define ECRYPTFS_MSG_RESPONSE 103
403 	u8 type;
404 	u32 index;
405 	/* Counter converts to a sequence number. Each message sent
406 	 * out for which we expect a response has an associated
407 	 * sequence number. The response must have the same sequence
408 	 * number as the counter for the msg_stc for the message to be
409 	 * valid. */
410 	u32 counter;
411 	size_t msg_size;
412 	struct ecryptfs_message *msg;
413 	struct task_struct *task;
414 	struct list_head node;
415 	struct list_head daemon_out_list;
416 	struct mutex mux;
417 };
418 
419 struct ecryptfs_daemon {
420 #define ECRYPTFS_DAEMON_IN_READ      0x00000001
421 #define ECRYPTFS_DAEMON_IN_POLL      0x00000002
422 #define ECRYPTFS_DAEMON_ZOMBIE       0x00000004
423 #define ECRYPTFS_DAEMON_MISCDEV_OPEN 0x00000008
424 	u32 flags;
425 	u32 num_queued_msg_ctx;
426 	struct file *file;
427 	struct mutex mux;
428 	struct list_head msg_ctx_out_queue;
429 	wait_queue_head_t wait;
430 	struct hlist_node euid_chain;
431 };
432 
433 #ifdef CONFIG_ECRYPT_FS_MESSAGING
434 extern struct mutex ecryptfs_daemon_hash_mux;
435 #endif
436 
437 static inline size_t
438 ecryptfs_lower_header_size(struct ecryptfs_crypt_stat *crypt_stat)
439 {
440 	if (crypt_stat->flags & ECRYPTFS_METADATA_IN_XATTR)
441 		return 0;
442 	return crypt_stat->metadata_size;
443 }
444 
445 static inline struct ecryptfs_file_info *
446 ecryptfs_file_to_private(struct file *file)
447 {
448 	return file->private_data;
449 }
450 
451 static inline void
452 ecryptfs_set_file_private(struct file *file,
453 			  struct ecryptfs_file_info *file_info)
454 {
455 	file->private_data = file_info;
456 }
457 
458 static inline struct file *ecryptfs_file_to_lower(struct file *file)
459 {
460 	return ((struct ecryptfs_file_info *)file->private_data)->wfi_file;
461 }
462 
463 static inline void
464 ecryptfs_set_file_lower(struct file *file, struct file *lower_file)
465 {
466 	((struct ecryptfs_file_info *)file->private_data)->wfi_file =
467 		lower_file;
468 }
469 
470 static inline struct ecryptfs_inode_info *
471 ecryptfs_inode_to_private(struct inode *inode)
472 {
473 	return container_of(inode, struct ecryptfs_inode_info, vfs_inode);
474 }
475 
476 static inline struct inode *ecryptfs_inode_to_lower(struct inode *inode)
477 {
478 	return ecryptfs_inode_to_private(inode)->wii_inode;
479 }
480 
481 static inline void
482 ecryptfs_set_inode_lower(struct inode *inode, struct inode *lower_inode)
483 {
484 	ecryptfs_inode_to_private(inode)->wii_inode = lower_inode;
485 }
486 
487 static inline struct ecryptfs_sb_info *
488 ecryptfs_superblock_to_private(struct super_block *sb)
489 {
490 	return (struct ecryptfs_sb_info *)sb->s_fs_info;
491 }
492 
493 static inline void
494 ecryptfs_set_superblock_private(struct super_block *sb,
495 				struct ecryptfs_sb_info *sb_info)
496 {
497 	sb->s_fs_info = sb_info;
498 }
499 
500 static inline struct super_block *
501 ecryptfs_superblock_to_lower(struct super_block *sb)
502 {
503 	return ((struct ecryptfs_sb_info *)sb->s_fs_info)->wsi_sb;
504 }
505 
506 static inline void
507 ecryptfs_set_superblock_lower(struct super_block *sb,
508 			      struct super_block *lower_sb)
509 {
510 	((struct ecryptfs_sb_info *)sb->s_fs_info)->wsi_sb = lower_sb;
511 }
512 
513 static inline struct ecryptfs_dentry_info *
514 ecryptfs_dentry_to_private(struct dentry *dentry)
515 {
516 	return (struct ecryptfs_dentry_info *)dentry->d_fsdata;
517 }
518 
519 static inline void
520 ecryptfs_set_dentry_private(struct dentry *dentry,
521 			    struct ecryptfs_dentry_info *dentry_info)
522 {
523 	dentry->d_fsdata = dentry_info;
524 }
525 
526 static inline struct dentry *
527 ecryptfs_dentry_to_lower(struct dentry *dentry)
528 {
529 	return ((struct ecryptfs_dentry_info *)dentry->d_fsdata)->lower_path.dentry;
530 }
531 
532 static inline struct vfsmount *
533 ecryptfs_dentry_to_lower_mnt(struct dentry *dentry)
534 {
535 	return ((struct ecryptfs_dentry_info *)dentry->d_fsdata)->lower_path.mnt;
536 }
537 
538 static inline struct path *
539 ecryptfs_dentry_to_lower_path(struct dentry *dentry)
540 {
541 	return &((struct ecryptfs_dentry_info *)dentry->d_fsdata)->lower_path;
542 }
543 
544 #define ecryptfs_printk(type, fmt, arg...) \
545         __ecryptfs_printk(type "%s: " fmt, __func__, ## arg);
546 __printf(1, 2)
547 void __ecryptfs_printk(const char *fmt, ...);
548 
549 extern const struct file_operations ecryptfs_main_fops;
550 extern const struct file_operations ecryptfs_dir_fops;
551 extern const struct inode_operations ecryptfs_main_iops;
552 extern const struct inode_operations ecryptfs_dir_iops;
553 extern const struct inode_operations ecryptfs_symlink_iops;
554 extern const struct super_operations ecryptfs_sops;
555 extern const struct dentry_operations ecryptfs_dops;
556 extern const struct address_space_operations ecryptfs_aops;
557 extern int ecryptfs_verbosity;
558 extern unsigned int ecryptfs_message_buf_len;
559 extern signed long ecryptfs_message_wait_timeout;
560 extern unsigned int ecryptfs_number_of_users;
561 
562 extern struct kmem_cache *ecryptfs_auth_tok_list_item_cache;
563 extern struct kmem_cache *ecryptfs_file_info_cache;
564 extern struct kmem_cache *ecryptfs_dentry_info_cache;
565 extern struct kmem_cache *ecryptfs_inode_info_cache;
566 extern struct kmem_cache *ecryptfs_sb_info_cache;
567 extern struct kmem_cache *ecryptfs_header_cache;
568 extern struct kmem_cache *ecryptfs_xattr_cache;
569 extern struct kmem_cache *ecryptfs_key_record_cache;
570 extern struct kmem_cache *ecryptfs_key_sig_cache;
571 extern struct kmem_cache *ecryptfs_global_auth_tok_cache;
572 extern struct kmem_cache *ecryptfs_key_tfm_cache;
573 
574 struct inode *ecryptfs_get_inode(struct inode *lower_inode,
575 				 struct super_block *sb);
576 void ecryptfs_i_size_init(const char *page_virt, struct inode *inode);
577 int ecryptfs_initialize_file(struct dentry *ecryptfs_dentry,
578 			     struct inode *ecryptfs_inode);
579 int ecryptfs_decode_and_decrypt_filename(char **decrypted_name,
580 					 size_t *decrypted_name_size,
581 					 struct super_block *sb,
582 					 const char *name, size_t name_size);
583 int ecryptfs_fill_zeros(struct file *file, loff_t new_length);
584 int ecryptfs_encrypt_and_encode_filename(
585 	char **encoded_name,
586 	size_t *encoded_name_size,
587 	struct ecryptfs_mount_crypt_stat *mount_crypt_stat,
588 	const char *name, size_t name_size);
589 struct dentry *ecryptfs_lower_dentry(struct dentry *this_dentry);
590 void ecryptfs_dump_hex(char *data, int bytes);
591 int virt_to_scatterlist(const void *addr, int size, struct scatterlist *sg,
592 			int sg_size);
593 int ecryptfs_compute_root_iv(struct ecryptfs_crypt_stat *crypt_stat);
594 void ecryptfs_rotate_iv(unsigned char *iv);
595 int ecryptfs_init_crypt_stat(struct ecryptfs_crypt_stat *crypt_stat);
596 void ecryptfs_destroy_crypt_stat(struct ecryptfs_crypt_stat *crypt_stat);
597 void ecryptfs_destroy_mount_crypt_stat(
598 	struct ecryptfs_mount_crypt_stat *mount_crypt_stat);
599 int ecryptfs_init_crypt_ctx(struct ecryptfs_crypt_stat *crypt_stat);
600 int ecryptfs_write_inode_size_to_metadata(struct inode *ecryptfs_inode);
601 int ecryptfs_encrypt_page(struct page *page);
602 int ecryptfs_decrypt_page(struct page *page);
603 int ecryptfs_write_metadata(struct dentry *ecryptfs_dentry,
604 			    struct inode *ecryptfs_inode);
605 int ecryptfs_read_metadata(struct dentry *ecryptfs_dentry);
606 int ecryptfs_new_file_context(struct inode *ecryptfs_inode);
607 void ecryptfs_write_crypt_stat_flags(char *page_virt,
608 				     struct ecryptfs_crypt_stat *crypt_stat,
609 				     size_t *written);
610 int ecryptfs_read_and_validate_header_region(struct inode *inode);
611 int ecryptfs_read_and_validate_xattr_region(struct dentry *dentry,
612 					    struct inode *inode);
613 u8 ecryptfs_code_for_cipher_string(char *cipher_name, size_t key_bytes);
614 int ecryptfs_cipher_code_to_string(char *str, u8 cipher_code);
615 void ecryptfs_set_default_sizes(struct ecryptfs_crypt_stat *crypt_stat);
616 int ecryptfs_generate_key_packet_set(char *dest_base,
617 				     struct ecryptfs_crypt_stat *crypt_stat,
618 				     struct dentry *ecryptfs_dentry,
619 				     size_t *len, size_t max);
620 int
621 ecryptfs_parse_packet_set(struct ecryptfs_crypt_stat *crypt_stat,
622 			  unsigned char *src, struct dentry *ecryptfs_dentry);
623 int ecryptfs_truncate(struct dentry *dentry, loff_t new_length);
624 ssize_t
625 ecryptfs_getxattr_lower(struct dentry *lower_dentry, struct inode *lower_inode,
626 			const char *name, void *value, size_t size);
627 int
628 ecryptfs_setxattr(struct dentry *dentry, struct inode *inode, const char *name,
629 		  const void *value, size_t size, int flags);
630 int ecryptfs_read_xattr_region(char *page_virt, struct inode *ecryptfs_inode);
631 #ifdef CONFIG_ECRYPT_FS_MESSAGING
632 int ecryptfs_process_response(struct ecryptfs_daemon *daemon,
633 			      struct ecryptfs_message *msg, u32 seq);
634 int ecryptfs_send_message(char *data, int data_len,
635 			  struct ecryptfs_msg_ctx **msg_ctx);
636 int ecryptfs_wait_for_response(struct ecryptfs_msg_ctx *msg_ctx,
637 			       struct ecryptfs_message **emsg);
638 int ecryptfs_init_messaging(void);
639 void ecryptfs_release_messaging(void);
640 #else
641 static inline int ecryptfs_init_messaging(void)
642 {
643 	return 0;
644 }
645 static inline void ecryptfs_release_messaging(void)
646 { }
647 static inline int ecryptfs_send_message(char *data, int data_len,
648 					struct ecryptfs_msg_ctx **msg_ctx)
649 {
650 	return -ENOTCONN;
651 }
652 static inline int ecryptfs_wait_for_response(struct ecryptfs_msg_ctx *msg_ctx,
653 					     struct ecryptfs_message **emsg)
654 {
655 	return -ENOMSG;
656 }
657 #endif
658 
659 void
660 ecryptfs_write_header_metadata(char *virt,
661 			       struct ecryptfs_crypt_stat *crypt_stat,
662 			       size_t *written);
663 int ecryptfs_add_keysig(struct ecryptfs_crypt_stat *crypt_stat, char *sig);
664 int
665 ecryptfs_add_global_auth_tok(struct ecryptfs_mount_crypt_stat *mount_crypt_stat,
666 			   char *sig, u32 global_auth_tok_flags);
667 int ecryptfs_get_global_auth_tok_for_sig(
668 	struct ecryptfs_global_auth_tok **global_auth_tok,
669 	struct ecryptfs_mount_crypt_stat *mount_crypt_stat, char *sig);
670 int
671 ecryptfs_add_new_key_tfm(struct ecryptfs_key_tfm **key_tfm, char *cipher_name,
672 			 size_t key_size);
673 int ecryptfs_init_crypto(void);
674 int ecryptfs_destroy_crypto(void);
675 int ecryptfs_tfm_exists(char *cipher_name, struct ecryptfs_key_tfm **key_tfm);
676 int ecryptfs_get_tfm_and_mutex_for_cipher_name(struct crypto_skcipher **tfm,
677 					       struct mutex **tfm_mutex,
678 					       char *cipher_name);
679 int ecryptfs_keyring_auth_tok_for_sig(struct key **auth_tok_key,
680 				      struct ecryptfs_auth_tok **auth_tok,
681 				      char *sig);
682 int ecryptfs_write_lower(struct inode *ecryptfs_inode, char *data,
683 			 loff_t offset, size_t size);
684 int ecryptfs_write_lower_page_segment(struct inode *ecryptfs_inode,
685 				      struct page *page_for_lower,
686 				      size_t offset_in_page, size_t size);
687 int ecryptfs_write(struct inode *inode, char *data, loff_t offset, size_t size);
688 int ecryptfs_read_lower(char *data, loff_t offset, size_t size,
689 			struct inode *ecryptfs_inode);
690 int ecryptfs_read_lower_page_segment(struct page *page_for_ecryptfs,
691 				     pgoff_t page_index,
692 				     size_t offset_in_page, size_t size,
693 				     struct inode *ecryptfs_inode);
694 struct page *ecryptfs_get_locked_page(struct inode *inode, loff_t index);
695 int ecryptfs_parse_packet_length(unsigned char *data, size_t *size,
696 				 size_t *length_size);
697 int ecryptfs_write_packet_length(char *dest, size_t size,
698 				 size_t *packet_size_length);
699 #ifdef CONFIG_ECRYPT_FS_MESSAGING
700 int ecryptfs_init_ecryptfs_miscdev(void);
701 void ecryptfs_destroy_ecryptfs_miscdev(void);
702 int ecryptfs_send_miscdev(char *data, size_t data_size,
703 			  struct ecryptfs_msg_ctx *msg_ctx, u8 msg_type,
704 			  u16 msg_flags, struct ecryptfs_daemon *daemon);
705 void ecryptfs_msg_ctx_alloc_to_free(struct ecryptfs_msg_ctx *msg_ctx);
706 int
707 ecryptfs_spawn_daemon(struct ecryptfs_daemon **daemon, struct file *file);
708 int ecryptfs_exorcise_daemon(struct ecryptfs_daemon *daemon);
709 int ecryptfs_find_daemon_by_euid(struct ecryptfs_daemon **daemon);
710 #endif
711 int ecryptfs_init_kthread(void);
712 void ecryptfs_destroy_kthread(void);
713 int ecryptfs_privileged_open(struct file **lower_file,
714 			     struct dentry *lower_dentry,
715 			     struct vfsmount *lower_mnt,
716 			     const struct cred *cred);
717 int ecryptfs_get_lower_file(struct dentry *dentry, struct inode *inode);
718 void ecryptfs_put_lower_file(struct inode *inode);
719 int
720 ecryptfs_write_tag_70_packet(char *dest, size_t *remaining_bytes,
721 			     size_t *packet_size,
722 			     struct ecryptfs_mount_crypt_stat *mount_crypt_stat,
723 			     char *filename, size_t filename_size);
724 int
725 ecryptfs_parse_tag_70_packet(char **filename, size_t *filename_size,
726 			     size_t *packet_size,
727 			     struct ecryptfs_mount_crypt_stat *mount_crypt_stat,
728 			     char *data, size_t max_packet_size);
729 int ecryptfs_set_f_namelen(long *namelen, long lower_namelen,
730 			   struct ecryptfs_mount_crypt_stat *mount_crypt_stat);
731 int ecryptfs_derive_iv(char *iv, struct ecryptfs_crypt_stat *crypt_stat,
732 		       loff_t offset);
733 
734 extern const struct xattr_handler *ecryptfs_xattr_handlers[];
735 
736 #endif /* #ifndef ECRYPTFS_KERNEL_H */
737