xref: /linux/fs/ecryptfs/ecryptfs_kernel.h (revision 494b9ae7abb84e6d88d7587906aff29dd26cf9d0)
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/fs.h>
35 #include <linux/fs_stack.h>
36 #include <linux/namei.h>
37 #include <linux/scatterlist.h>
38 #include <linux/hash.h>
39 #include <linux/nsproxy.h>
40 #include <linux/backing-dev.h>
41 #include <linux/ecryptfs.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 	struct encrypted_key_payload *payload;
88 
89 	if (key->type != &key_type_encrypted)
90 		return NULL;
91 
92 	payload = key->payload.data[0];
93 	if (!payload)
94 		return ERR_PTR(-EKEYREVOKED);
95 
96 	return (struct ecryptfs_auth_tok *)payload->payload_data;
97 }
98 
99 static inline struct key *ecryptfs_get_encrypted_key(char *sig)
100 {
101 	return request_key(&key_type_encrypted, sig, NULL);
102 }
103 
104 #else
105 static inline struct ecryptfs_auth_tok *
106 ecryptfs_get_encrypted_key_payload_data(struct key *key)
107 {
108 	return NULL;
109 }
110 
111 static inline struct key *ecryptfs_get_encrypted_key(char *sig)
112 {
113 	return ERR_PTR(-ENOKEY);
114 }
115 
116 #endif /* CONFIG_ENCRYPTED_KEYS */
117 
118 static inline struct ecryptfs_auth_tok *
119 ecryptfs_get_key_payload_data(struct key *key)
120 {
121 	struct ecryptfs_auth_tok *auth_tok;
122 	struct user_key_payload *ukp;
123 
124 	auth_tok = ecryptfs_get_encrypted_key_payload_data(key);
125 	if (auth_tok)
126 		return auth_tok;
127 
128 	ukp = user_key_payload_locked(key);
129 	if (!ukp)
130 		return ERR_PTR(-EKEYREVOKED);
131 
132 	return (struct ecryptfs_auth_tok *)ukp->data;
133 }
134 
135 #define ECRYPTFS_MAX_KEYSET_SIZE 1024
136 #define ECRYPTFS_MAX_CIPHER_NAME_SIZE 31
137 #define ECRYPTFS_MAX_NUM_ENC_KEYS 64
138 #define ECRYPTFS_MAX_IV_BYTES 16	/* 128 bits */
139 #define ECRYPTFS_SALT_BYTES 2
140 #define MAGIC_ECRYPTFS_MARKER 0x3c81b7f5
141 #define MAGIC_ECRYPTFS_MARKER_SIZE_BYTES 8	/* 4*2 */
142 #define ECRYPTFS_FILE_SIZE_BYTES (sizeof(u64))
143 #define ECRYPTFS_SIZE_AND_MARKER_BYTES (ECRYPTFS_FILE_SIZE_BYTES \
144 					+ MAGIC_ECRYPTFS_MARKER_SIZE_BYTES)
145 #define ECRYPTFS_DEFAULT_CIPHER "aes"
146 #define ECRYPTFS_DEFAULT_KEY_BYTES 16
147 #define ECRYPTFS_DEFAULT_HASH "md5"
148 #define ECRYPTFS_TAG_70_DIGEST ECRYPTFS_DEFAULT_HASH
149 #define ECRYPTFS_TAG_1_PACKET_TYPE 0x01
150 #define ECRYPTFS_TAG_3_PACKET_TYPE 0x8C
151 #define ECRYPTFS_TAG_11_PACKET_TYPE 0xED
152 #define ECRYPTFS_TAG_64_PACKET_TYPE 0x40
153 #define ECRYPTFS_TAG_65_PACKET_TYPE 0x41
154 #define ECRYPTFS_TAG_66_PACKET_TYPE 0x42
155 #define ECRYPTFS_TAG_67_PACKET_TYPE 0x43
156 #define ECRYPTFS_TAG_70_PACKET_TYPE 0x46 /* FNEK-encrypted filename
157 					  * as dentry name */
158 #define ECRYPTFS_TAG_71_PACKET_TYPE 0x47 /* FNEK-encrypted filename in
159 					  * metadata */
160 #define ECRYPTFS_TAG_72_PACKET_TYPE 0x48 /* FEK-encrypted filename as
161 					  * dentry name */
162 #define ECRYPTFS_TAG_73_PACKET_TYPE 0x49 /* FEK-encrypted filename as
163 					  * metadata */
164 #define ECRYPTFS_MIN_PKT_LEN_SIZE 1 /* Min size to specify packet length */
165 #define ECRYPTFS_MAX_PKT_LEN_SIZE 2 /* Pass at least this many bytes to
166 				     * ecryptfs_parse_packet_length() and
167 				     * ecryptfs_write_packet_length()
168 				     */
169 /* Constraint: ECRYPTFS_FILENAME_MIN_RANDOM_PREPEND_BYTES >=
170  * ECRYPTFS_MAX_IV_BYTES */
171 #define ECRYPTFS_FILENAME_MIN_RANDOM_PREPEND_BYTES 16
172 #define ECRYPTFS_NON_NULL 0x42 /* A reasonable substitute for NULL */
173 #define MD5_DIGEST_SIZE 16
174 #define ECRYPTFS_TAG_70_DIGEST_SIZE MD5_DIGEST_SIZE
175 #define ECRYPTFS_TAG_70_MIN_METADATA_SIZE (1 + ECRYPTFS_MIN_PKT_LEN_SIZE \
176 					   + ECRYPTFS_SIG_SIZE + 1 + 1)
177 #define ECRYPTFS_TAG_70_MAX_METADATA_SIZE (1 + ECRYPTFS_MAX_PKT_LEN_SIZE \
178 					   + ECRYPTFS_SIG_SIZE + 1 + 1)
179 #define ECRYPTFS_FEK_ENCRYPTED_FILENAME_PREFIX "ECRYPTFS_FEK_ENCRYPTED."
180 #define ECRYPTFS_FEK_ENCRYPTED_FILENAME_PREFIX_SIZE 23
181 #define ECRYPTFS_FNEK_ENCRYPTED_FILENAME_PREFIX "ECRYPTFS_FNEK_ENCRYPTED."
182 #define ECRYPTFS_FNEK_ENCRYPTED_FILENAME_PREFIX_SIZE 24
183 #define ECRYPTFS_ENCRYPTED_DENTRY_NAME_LEN (18 + 1 + 4 + 1 + 32)
184 
185 #ifdef CONFIG_ECRYPT_FS_MESSAGING
186 # define ECRYPTFS_VERSIONING_MASK_MESSAGING (ECRYPTFS_VERSIONING_DEVMISC \
187 					     | ECRYPTFS_VERSIONING_PUBKEY)
188 #else
189 # define ECRYPTFS_VERSIONING_MASK_MESSAGING 0
190 #endif
191 
192 #define ECRYPTFS_VERSIONING_MASK (ECRYPTFS_VERSIONING_PASSPHRASE \
193 				  | ECRYPTFS_VERSIONING_PLAINTEXT_PASSTHROUGH \
194 				  | ECRYPTFS_VERSIONING_XATTR \
195 				  | ECRYPTFS_VERSIONING_MULTKEY \
196 				  | ECRYPTFS_VERSIONING_MASK_MESSAGING \
197 				  | ECRYPTFS_VERSIONING_FILENAME_ENCRYPTION)
198 struct ecryptfs_key_sig {
199 	struct list_head crypt_stat_list;
200 	char keysig[ECRYPTFS_SIG_SIZE_HEX + 1];
201 };
202 
203 struct ecryptfs_filename {
204 	struct list_head crypt_stat_list;
205 #define ECRYPTFS_FILENAME_CONTAINS_DECRYPTED 0x00000001
206 	u32 flags;
207 	u32 seq_no;
208 	char *filename;
209 	char *encrypted_filename;
210 	size_t filename_size;
211 	size_t encrypted_filename_size;
212 	char fnek_sig[ECRYPTFS_SIG_SIZE_HEX];
213 	char dentry_name[ECRYPTFS_ENCRYPTED_DENTRY_NAME_LEN + 1];
214 };
215 
216 /**
217  * This is the primary struct associated with each encrypted file.
218  *
219  * TODO: cache align/pack?
220  */
221 struct ecryptfs_crypt_stat {
222 #define ECRYPTFS_STRUCT_INITIALIZED   0x00000001
223 #define ECRYPTFS_POLICY_APPLIED       0x00000002
224 #define ECRYPTFS_ENCRYPTED            0x00000004
225 #define ECRYPTFS_SECURITY_WARNING     0x00000008
226 #define ECRYPTFS_ENABLE_HMAC          0x00000010
227 #define ECRYPTFS_ENCRYPT_IV_PAGES     0x00000020
228 #define ECRYPTFS_KEY_VALID            0x00000040
229 #define ECRYPTFS_METADATA_IN_XATTR    0x00000080
230 #define ECRYPTFS_VIEW_AS_ENCRYPTED    0x00000100
231 #define ECRYPTFS_KEY_SET              0x00000200
232 #define ECRYPTFS_ENCRYPT_FILENAMES    0x00000400
233 #define ECRYPTFS_ENCFN_USE_MOUNT_FNEK 0x00000800
234 #define ECRYPTFS_ENCFN_USE_FEK        0x00001000
235 #define ECRYPTFS_UNLINK_SIGS          0x00002000
236 #define ECRYPTFS_I_SIZE_INITIALIZED   0x00004000
237 	u32 flags;
238 	unsigned int file_version;
239 	size_t iv_bytes;
240 	size_t metadata_size;
241 	size_t extent_size; /* Data extent size; default is 4096 */
242 	size_t key_size;
243 	size_t extent_shift;
244 	unsigned int extent_mask;
245 	struct ecryptfs_mount_crypt_stat *mount_crypt_stat;
246 	struct crypto_skcipher *tfm;
247 	struct crypto_shash *hash_tfm; /* Crypto context for generating
248 					* the initialization vectors */
249 	unsigned char cipher[ECRYPTFS_MAX_CIPHER_NAME_SIZE + 1];
250 	unsigned char key[ECRYPTFS_MAX_KEY_BYTES];
251 	unsigned char root_iv[ECRYPTFS_MAX_IV_BYTES];
252 	struct list_head keysig_list;
253 	struct mutex keysig_list_mutex;
254 	struct mutex cs_tfm_mutex;
255 	struct mutex cs_mutex;
256 };
257 
258 /* inode private data. */
259 struct ecryptfs_inode_info {
260 	struct inode vfs_inode;
261 	struct inode *wii_inode;
262 	struct mutex lower_file_mutex;
263 	atomic_t lower_file_count;
264 	struct file *lower_file;
265 	struct ecryptfs_crypt_stat crypt_stat;
266 };
267 
268 /* dentry private data. Each dentry must keep track of a lower
269  * vfsmount too. */
270 struct ecryptfs_dentry_info {
271 	struct path lower_path;
272 	union {
273 		struct ecryptfs_crypt_stat *crypt_stat;
274 		struct rcu_head rcu;
275 	};
276 };
277 
278 /**
279  * ecryptfs_global_auth_tok - A key used to encrypt all new files under the mountpoint
280  * @flags: Status flags
281  * @mount_crypt_stat_list: These auth_toks hang off the mount-wide
282  *                         cryptographic context. Every time a new
283  *                         inode comes into existence, eCryptfs copies
284  *                         the auth_toks on that list to the set of
285  *                         auth_toks on the inode's crypt_stat
286  * @global_auth_tok_key: The key from the user's keyring for the sig
287  * @global_auth_tok: The key contents
288  * @sig: The key identifier
289  *
290  * ecryptfs_global_auth_tok structs refer to authentication token keys
291  * in the user keyring that apply to newly created files. A list of
292  * these objects hangs off of the mount_crypt_stat struct for any
293  * given eCryptfs mount. This struct maintains a reference to both the
294  * key contents and the key itself so that the key can be put on
295  * unmount.
296  */
297 struct ecryptfs_global_auth_tok {
298 #define ECRYPTFS_AUTH_TOK_INVALID 0x00000001
299 #define ECRYPTFS_AUTH_TOK_FNEK    0x00000002
300 	u32 flags;
301 	struct list_head mount_crypt_stat_list;
302 	struct key *global_auth_tok_key;
303 	unsigned char sig[ECRYPTFS_SIG_SIZE_HEX + 1];
304 };
305 
306 /**
307  * ecryptfs_key_tfm - Persistent key tfm
308  * @key_tfm: crypto API handle to the key
309  * @key_size: Key size in bytes
310  * @key_tfm_mutex: Mutex to ensure only one operation in eCryptfs is
311  *                 using the persistent TFM at any point in time
312  * @key_tfm_list: Handle to hang this off the module-wide TFM list
313  * @cipher_name: String name for the cipher for this TFM
314  *
315  * Typically, eCryptfs will use the same ciphers repeatedly throughout
316  * the course of its operations. In order to avoid unnecessarily
317  * destroying and initializing the same cipher repeatedly, eCryptfs
318  * keeps a list of crypto API contexts around to use when needed.
319  */
320 struct ecryptfs_key_tfm {
321 	struct crypto_skcipher *key_tfm;
322 	size_t key_size;
323 	struct mutex key_tfm_mutex;
324 	struct list_head key_tfm_list;
325 	unsigned char cipher_name[ECRYPTFS_MAX_CIPHER_NAME_SIZE + 1];
326 };
327 
328 extern struct mutex key_tfm_list_mutex;
329 
330 /**
331  * This struct is to enable a mount-wide passphrase/salt combo. This
332  * is more or less a stopgap to provide similar functionality to other
333  * crypto filesystems like EncFS or CFS until full policy support is
334  * implemented in eCryptfs.
335  */
336 struct ecryptfs_mount_crypt_stat {
337 	/* Pointers to memory we do not own, do not free these */
338 #define ECRYPTFS_PLAINTEXT_PASSTHROUGH_ENABLED 0x00000001
339 #define ECRYPTFS_XATTR_METADATA_ENABLED        0x00000002
340 #define ECRYPTFS_ENCRYPTED_VIEW_ENABLED        0x00000004
341 #define ECRYPTFS_MOUNT_CRYPT_STAT_INITIALIZED  0x00000008
342 #define ECRYPTFS_GLOBAL_ENCRYPT_FILENAMES      0x00000010
343 #define ECRYPTFS_GLOBAL_ENCFN_USE_MOUNT_FNEK   0x00000020
344 #define ECRYPTFS_GLOBAL_ENCFN_USE_FEK          0x00000040
345 #define ECRYPTFS_GLOBAL_MOUNT_AUTH_TOK_ONLY    0x00000080
346 	u32 flags;
347 	struct list_head global_auth_tok_list;
348 	struct mutex global_auth_tok_list_mutex;
349 	size_t global_default_cipher_key_size;
350 	size_t global_default_fn_cipher_key_bytes;
351 	unsigned char global_default_cipher_name[ECRYPTFS_MAX_CIPHER_NAME_SIZE
352 						 + 1];
353 	unsigned char global_default_fn_cipher_name[
354 		ECRYPTFS_MAX_CIPHER_NAME_SIZE + 1];
355 	char global_default_fnek_sig[ECRYPTFS_SIG_SIZE_HEX + 1];
356 };
357 
358 /* superblock private data. */
359 struct ecryptfs_sb_info {
360 	struct super_block *wsi_sb;
361 	struct ecryptfs_mount_crypt_stat mount_crypt_stat;
362 };
363 
364 /* file private data. */
365 struct ecryptfs_file_info {
366 	struct file *wfi_file;
367 	struct ecryptfs_crypt_stat *crypt_stat;
368 };
369 
370 /* auth_tok <=> encrypted_session_key mappings */
371 struct ecryptfs_auth_tok_list_item {
372 	unsigned char encrypted_session_key[ECRYPTFS_MAX_KEY_BYTES];
373 	struct list_head list;
374 	struct ecryptfs_auth_tok auth_tok;
375 };
376 
377 struct ecryptfs_message {
378 	/* Can never be greater than ecryptfs_message_buf_len */
379 	/* Used to find the parent msg_ctx */
380 	/* Inherits from msg_ctx->index */
381 	u32 index;
382 	u32 data_len;
383 	u8 data[];
384 };
385 
386 struct ecryptfs_msg_ctx {
387 #define ECRYPTFS_MSG_CTX_STATE_FREE     0x01
388 #define ECRYPTFS_MSG_CTX_STATE_PENDING  0x02
389 #define ECRYPTFS_MSG_CTX_STATE_DONE     0x03
390 #define ECRYPTFS_MSG_CTX_STATE_NO_REPLY 0x04
391 	u8 state;
392 #define ECRYPTFS_MSG_HELO 100
393 #define ECRYPTFS_MSG_QUIT 101
394 #define ECRYPTFS_MSG_REQUEST 102
395 #define ECRYPTFS_MSG_RESPONSE 103
396 	u8 type;
397 	u32 index;
398 	/* Counter converts to a sequence number. Each message sent
399 	 * out for which we expect a response has an associated
400 	 * sequence number. The response must have the same sequence
401 	 * number as the counter for the msg_stc for the message to be
402 	 * valid. */
403 	u32 counter;
404 	size_t msg_size;
405 	struct ecryptfs_message *msg;
406 	struct task_struct *task;
407 	struct list_head node;
408 	struct list_head daemon_out_list;
409 	struct mutex mux;
410 };
411 
412 struct ecryptfs_daemon {
413 #define ECRYPTFS_DAEMON_IN_READ      0x00000001
414 #define ECRYPTFS_DAEMON_IN_POLL      0x00000002
415 #define ECRYPTFS_DAEMON_ZOMBIE       0x00000004
416 #define ECRYPTFS_DAEMON_MISCDEV_OPEN 0x00000008
417 	u32 flags;
418 	u32 num_queued_msg_ctx;
419 	struct file *file;
420 	struct mutex mux;
421 	struct list_head msg_ctx_out_queue;
422 	wait_queue_head_t wait;
423 	struct hlist_node euid_chain;
424 };
425 
426 #ifdef CONFIG_ECRYPT_FS_MESSAGING
427 extern struct mutex ecryptfs_daemon_hash_mux;
428 #endif
429 
430 static inline size_t
431 ecryptfs_lower_header_size(struct ecryptfs_crypt_stat *crypt_stat)
432 {
433 	if (crypt_stat->flags & ECRYPTFS_METADATA_IN_XATTR)
434 		return 0;
435 	return crypt_stat->metadata_size;
436 }
437 
438 static inline struct ecryptfs_file_info *
439 ecryptfs_file_to_private(struct file *file)
440 {
441 	return file->private_data;
442 }
443 
444 static inline void
445 ecryptfs_set_file_private(struct file *file,
446 			  struct ecryptfs_file_info *file_info)
447 {
448 	file->private_data = file_info;
449 }
450 
451 static inline struct file *ecryptfs_file_to_lower(struct file *file)
452 {
453 	return ((struct ecryptfs_file_info *)file->private_data)->wfi_file;
454 }
455 
456 static inline void
457 ecryptfs_set_file_lower(struct file *file, struct file *lower_file)
458 {
459 	((struct ecryptfs_file_info *)file->private_data)->wfi_file =
460 		lower_file;
461 }
462 
463 static inline struct ecryptfs_inode_info *
464 ecryptfs_inode_to_private(struct inode *inode)
465 {
466 	return container_of(inode, struct ecryptfs_inode_info, vfs_inode);
467 }
468 
469 static inline struct inode *ecryptfs_inode_to_lower(struct inode *inode)
470 {
471 	return ecryptfs_inode_to_private(inode)->wii_inode;
472 }
473 
474 static inline void
475 ecryptfs_set_inode_lower(struct inode *inode, struct inode *lower_inode)
476 {
477 	ecryptfs_inode_to_private(inode)->wii_inode = lower_inode;
478 }
479 
480 static inline struct ecryptfs_sb_info *
481 ecryptfs_superblock_to_private(struct super_block *sb)
482 {
483 	return (struct ecryptfs_sb_info *)sb->s_fs_info;
484 }
485 
486 static inline void
487 ecryptfs_set_superblock_private(struct super_block *sb,
488 				struct ecryptfs_sb_info *sb_info)
489 {
490 	sb->s_fs_info = sb_info;
491 }
492 
493 static inline struct super_block *
494 ecryptfs_superblock_to_lower(struct super_block *sb)
495 {
496 	return ((struct ecryptfs_sb_info *)sb->s_fs_info)->wsi_sb;
497 }
498 
499 static inline void
500 ecryptfs_set_superblock_lower(struct super_block *sb,
501 			      struct super_block *lower_sb)
502 {
503 	((struct ecryptfs_sb_info *)sb->s_fs_info)->wsi_sb = lower_sb;
504 }
505 
506 static inline struct ecryptfs_dentry_info *
507 ecryptfs_dentry_to_private(struct dentry *dentry)
508 {
509 	return (struct ecryptfs_dentry_info *)dentry->d_fsdata;
510 }
511 
512 static inline void
513 ecryptfs_set_dentry_private(struct dentry *dentry,
514 			    struct ecryptfs_dentry_info *dentry_info)
515 {
516 	dentry->d_fsdata = dentry_info;
517 }
518 
519 static inline struct dentry *
520 ecryptfs_dentry_to_lower(struct dentry *dentry)
521 {
522 	return ((struct ecryptfs_dentry_info *)dentry->d_fsdata)->lower_path.dentry;
523 }
524 
525 static inline struct vfsmount *
526 ecryptfs_dentry_to_lower_mnt(struct dentry *dentry)
527 {
528 	return ((struct ecryptfs_dentry_info *)dentry->d_fsdata)->lower_path.mnt;
529 }
530 
531 static inline struct path *
532 ecryptfs_dentry_to_lower_path(struct dentry *dentry)
533 {
534 	return &((struct ecryptfs_dentry_info *)dentry->d_fsdata)->lower_path;
535 }
536 
537 #define ecryptfs_printk(type, fmt, arg...) \
538         __ecryptfs_printk(type "%s: " fmt, __func__, ## arg);
539 __printf(1, 2)
540 void __ecryptfs_printk(const char *fmt, ...);
541 
542 extern const struct file_operations ecryptfs_main_fops;
543 extern const struct file_operations ecryptfs_dir_fops;
544 extern const struct inode_operations ecryptfs_main_iops;
545 extern const struct inode_operations ecryptfs_dir_iops;
546 extern const struct inode_operations ecryptfs_symlink_iops;
547 extern const struct super_operations ecryptfs_sops;
548 extern const struct dentry_operations ecryptfs_dops;
549 extern const struct address_space_operations ecryptfs_aops;
550 extern int ecryptfs_verbosity;
551 extern unsigned int ecryptfs_message_buf_len;
552 extern signed long ecryptfs_message_wait_timeout;
553 extern unsigned int ecryptfs_number_of_users;
554 
555 extern struct kmem_cache *ecryptfs_auth_tok_list_item_cache;
556 extern struct kmem_cache *ecryptfs_file_info_cache;
557 extern struct kmem_cache *ecryptfs_dentry_info_cache;
558 extern struct kmem_cache *ecryptfs_inode_info_cache;
559 extern struct kmem_cache *ecryptfs_sb_info_cache;
560 extern struct kmem_cache *ecryptfs_header_cache;
561 extern struct kmem_cache *ecryptfs_xattr_cache;
562 extern struct kmem_cache *ecryptfs_key_record_cache;
563 extern struct kmem_cache *ecryptfs_key_sig_cache;
564 extern struct kmem_cache *ecryptfs_global_auth_tok_cache;
565 extern struct kmem_cache *ecryptfs_key_tfm_cache;
566 
567 struct inode *ecryptfs_get_inode(struct inode *lower_inode,
568 				 struct super_block *sb);
569 void ecryptfs_i_size_init(const char *page_virt, struct inode *inode);
570 int ecryptfs_initialize_file(struct dentry *ecryptfs_dentry,
571 			     struct inode *ecryptfs_inode);
572 int ecryptfs_decode_and_decrypt_filename(char **decrypted_name,
573 					 size_t *decrypted_name_size,
574 					 struct super_block *sb,
575 					 const char *name, size_t name_size);
576 int ecryptfs_fill_zeros(struct file *file, loff_t new_length);
577 int ecryptfs_encrypt_and_encode_filename(
578 	char **encoded_name,
579 	size_t *encoded_name_size,
580 	struct ecryptfs_mount_crypt_stat *mount_crypt_stat,
581 	const char *name, size_t name_size);
582 struct dentry *ecryptfs_lower_dentry(struct dentry *this_dentry);
583 void ecryptfs_dump_hex(char *data, int bytes);
584 int virt_to_scatterlist(const void *addr, int size, struct scatterlist *sg,
585 			int sg_size);
586 int ecryptfs_compute_root_iv(struct ecryptfs_crypt_stat *crypt_stat);
587 void ecryptfs_rotate_iv(unsigned char *iv);
588 int ecryptfs_init_crypt_stat(struct ecryptfs_crypt_stat *crypt_stat);
589 void ecryptfs_destroy_crypt_stat(struct ecryptfs_crypt_stat *crypt_stat);
590 void ecryptfs_destroy_mount_crypt_stat(
591 	struct ecryptfs_mount_crypt_stat *mount_crypt_stat);
592 int ecryptfs_init_crypt_ctx(struct ecryptfs_crypt_stat *crypt_stat);
593 int ecryptfs_write_inode_size_to_metadata(struct inode *ecryptfs_inode);
594 int ecryptfs_encrypt_page(struct page *page);
595 int ecryptfs_decrypt_page(struct page *page);
596 int ecryptfs_write_metadata(struct dentry *ecryptfs_dentry,
597 			    struct inode *ecryptfs_inode);
598 int ecryptfs_read_metadata(struct dentry *ecryptfs_dentry);
599 int ecryptfs_new_file_context(struct inode *ecryptfs_inode);
600 void ecryptfs_write_crypt_stat_flags(char *page_virt,
601 				     struct ecryptfs_crypt_stat *crypt_stat,
602 				     size_t *written);
603 int ecryptfs_read_and_validate_header_region(struct inode *inode);
604 int ecryptfs_read_and_validate_xattr_region(struct dentry *dentry,
605 					    struct inode *inode);
606 u8 ecryptfs_code_for_cipher_string(char *cipher_name, size_t key_bytes);
607 int ecryptfs_cipher_code_to_string(char *str, u8 cipher_code);
608 void ecryptfs_set_default_sizes(struct ecryptfs_crypt_stat *crypt_stat);
609 int ecryptfs_generate_key_packet_set(char *dest_base,
610 				     struct ecryptfs_crypt_stat *crypt_stat,
611 				     struct dentry *ecryptfs_dentry,
612 				     size_t *len, size_t max);
613 int
614 ecryptfs_parse_packet_set(struct ecryptfs_crypt_stat *crypt_stat,
615 			  unsigned char *src, struct dentry *ecryptfs_dentry);
616 int ecryptfs_truncate(struct dentry *dentry, loff_t new_length);
617 ssize_t
618 ecryptfs_getxattr_lower(struct dentry *lower_dentry, struct inode *lower_inode,
619 			const char *name, void *value, size_t size);
620 int
621 ecryptfs_setxattr(struct dentry *dentry, struct inode *inode, const char *name,
622 		  const void *value, size_t size, int flags);
623 int ecryptfs_read_xattr_region(char *page_virt, struct inode *ecryptfs_inode);
624 #ifdef CONFIG_ECRYPT_FS_MESSAGING
625 int ecryptfs_process_response(struct ecryptfs_daemon *daemon,
626 			      struct ecryptfs_message *msg, u32 seq);
627 int ecryptfs_send_message(char *data, int data_len,
628 			  struct ecryptfs_msg_ctx **msg_ctx);
629 int ecryptfs_wait_for_response(struct ecryptfs_msg_ctx *msg_ctx,
630 			       struct ecryptfs_message **emsg);
631 int ecryptfs_init_messaging(void);
632 void ecryptfs_release_messaging(void);
633 #else
634 static inline int ecryptfs_init_messaging(void)
635 {
636 	return 0;
637 }
638 static inline void ecryptfs_release_messaging(void)
639 { }
640 static inline int ecryptfs_send_message(char *data, int data_len,
641 					struct ecryptfs_msg_ctx **msg_ctx)
642 {
643 	return -ENOTCONN;
644 }
645 static inline int ecryptfs_wait_for_response(struct ecryptfs_msg_ctx *msg_ctx,
646 					     struct ecryptfs_message **emsg)
647 {
648 	return -ENOMSG;
649 }
650 #endif
651 
652 void
653 ecryptfs_write_header_metadata(char *virt,
654 			       struct ecryptfs_crypt_stat *crypt_stat,
655 			       size_t *written);
656 int ecryptfs_add_keysig(struct ecryptfs_crypt_stat *crypt_stat, char *sig);
657 int
658 ecryptfs_add_global_auth_tok(struct ecryptfs_mount_crypt_stat *mount_crypt_stat,
659 			   char *sig, u32 global_auth_tok_flags);
660 int ecryptfs_get_global_auth_tok_for_sig(
661 	struct ecryptfs_global_auth_tok **global_auth_tok,
662 	struct ecryptfs_mount_crypt_stat *mount_crypt_stat, char *sig);
663 int
664 ecryptfs_add_new_key_tfm(struct ecryptfs_key_tfm **key_tfm, char *cipher_name,
665 			 size_t key_size);
666 int ecryptfs_init_crypto(void);
667 int ecryptfs_destroy_crypto(void);
668 int ecryptfs_tfm_exists(char *cipher_name, struct ecryptfs_key_tfm **key_tfm);
669 int ecryptfs_get_tfm_and_mutex_for_cipher_name(struct crypto_skcipher **tfm,
670 					       struct mutex **tfm_mutex,
671 					       char *cipher_name);
672 int ecryptfs_keyring_auth_tok_for_sig(struct key **auth_tok_key,
673 				      struct ecryptfs_auth_tok **auth_tok,
674 				      char *sig);
675 int ecryptfs_write_lower(struct inode *ecryptfs_inode, char *data,
676 			 loff_t offset, size_t size);
677 int ecryptfs_write_lower_page_segment(struct inode *ecryptfs_inode,
678 				      struct page *page_for_lower,
679 				      size_t offset_in_page, size_t size);
680 int ecryptfs_write(struct inode *inode, char *data, loff_t offset, size_t size);
681 int ecryptfs_read_lower(char *data, loff_t offset, size_t size,
682 			struct inode *ecryptfs_inode);
683 int ecryptfs_read_lower_page_segment(struct page *page_for_ecryptfs,
684 				     pgoff_t page_index,
685 				     size_t offset_in_page, size_t size,
686 				     struct inode *ecryptfs_inode);
687 struct page *ecryptfs_get_locked_page(struct inode *inode, loff_t index);
688 int ecryptfs_parse_packet_length(unsigned char *data, size_t *size,
689 				 size_t *length_size);
690 int ecryptfs_write_packet_length(char *dest, size_t size,
691 				 size_t *packet_size_length);
692 #ifdef CONFIG_ECRYPT_FS_MESSAGING
693 int ecryptfs_init_ecryptfs_miscdev(void);
694 void ecryptfs_destroy_ecryptfs_miscdev(void);
695 int ecryptfs_send_miscdev(char *data, size_t data_size,
696 			  struct ecryptfs_msg_ctx *msg_ctx, u8 msg_type,
697 			  u16 msg_flags, struct ecryptfs_daemon *daemon);
698 void ecryptfs_msg_ctx_alloc_to_free(struct ecryptfs_msg_ctx *msg_ctx);
699 int
700 ecryptfs_spawn_daemon(struct ecryptfs_daemon **daemon, struct file *file);
701 int ecryptfs_exorcise_daemon(struct ecryptfs_daemon *daemon);
702 int ecryptfs_find_daemon_by_euid(struct ecryptfs_daemon **daemon);
703 #endif
704 int ecryptfs_init_kthread(void);
705 void ecryptfs_destroy_kthread(void);
706 int ecryptfs_privileged_open(struct file **lower_file,
707 			     struct dentry *lower_dentry,
708 			     struct vfsmount *lower_mnt,
709 			     const struct cred *cred);
710 int ecryptfs_get_lower_file(struct dentry *dentry, struct inode *inode);
711 void ecryptfs_put_lower_file(struct inode *inode);
712 int
713 ecryptfs_write_tag_70_packet(char *dest, size_t *remaining_bytes,
714 			     size_t *packet_size,
715 			     struct ecryptfs_mount_crypt_stat *mount_crypt_stat,
716 			     char *filename, size_t filename_size);
717 int
718 ecryptfs_parse_tag_70_packet(char **filename, size_t *filename_size,
719 			     size_t *packet_size,
720 			     struct ecryptfs_mount_crypt_stat *mount_crypt_stat,
721 			     char *data, size_t max_packet_size);
722 int ecryptfs_set_f_namelen(long *namelen, long lower_namelen,
723 			   struct ecryptfs_mount_crypt_stat *mount_crypt_stat);
724 int ecryptfs_derive_iv(char *iv, struct ecryptfs_crypt_stat *crypt_stat,
725 		       loff_t offset);
726 
727 extern const struct xattr_handler *ecryptfs_xattr_handlers[];
728 
729 #endif /* #ifndef ECRYPTFS_KERNEL_H */
730