xref: /openbmc/linux/fs/ecryptfs/ecryptfs_kernel.h (revision bc5aa3a0)
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 	if (key->type == &key_type_encrypted)
88 		return (struct ecryptfs_auth_tok *)
89 			(&((struct encrypted_key_payload *)key->payload.data[0])->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 *)user_key_payload(key)->data;
121 	else
122 		return auth_tok;
123 }
124 
125 #define ECRYPTFS_MAX_KEYSET_SIZE 1024
126 #define ECRYPTFS_MAX_CIPHER_NAME_SIZE 31
127 #define ECRYPTFS_MAX_NUM_ENC_KEYS 64
128 #define ECRYPTFS_MAX_IV_BYTES 16	/* 128 bits */
129 #define ECRYPTFS_SALT_BYTES 2
130 #define MAGIC_ECRYPTFS_MARKER 0x3c81b7f5
131 #define MAGIC_ECRYPTFS_MARKER_SIZE_BYTES 8	/* 4*2 */
132 #define ECRYPTFS_FILE_SIZE_BYTES (sizeof(u64))
133 #define ECRYPTFS_SIZE_AND_MARKER_BYTES (ECRYPTFS_FILE_SIZE_BYTES \
134 					+ MAGIC_ECRYPTFS_MARKER_SIZE_BYTES)
135 #define ECRYPTFS_DEFAULT_CIPHER "aes"
136 #define ECRYPTFS_DEFAULT_KEY_BYTES 16
137 #define ECRYPTFS_DEFAULT_HASH "md5"
138 #define ECRYPTFS_TAG_70_DIGEST ECRYPTFS_DEFAULT_HASH
139 #define ECRYPTFS_TAG_1_PACKET_TYPE 0x01
140 #define ECRYPTFS_TAG_3_PACKET_TYPE 0x8C
141 #define ECRYPTFS_TAG_11_PACKET_TYPE 0xED
142 #define ECRYPTFS_TAG_64_PACKET_TYPE 0x40
143 #define ECRYPTFS_TAG_65_PACKET_TYPE 0x41
144 #define ECRYPTFS_TAG_66_PACKET_TYPE 0x42
145 #define ECRYPTFS_TAG_67_PACKET_TYPE 0x43
146 #define ECRYPTFS_TAG_70_PACKET_TYPE 0x46 /* FNEK-encrypted filename
147 					  * as dentry name */
148 #define ECRYPTFS_TAG_71_PACKET_TYPE 0x47 /* FNEK-encrypted filename in
149 					  * metadata */
150 #define ECRYPTFS_TAG_72_PACKET_TYPE 0x48 /* FEK-encrypted filename as
151 					  * dentry name */
152 #define ECRYPTFS_TAG_73_PACKET_TYPE 0x49 /* FEK-encrypted filename as
153 					  * metadata */
154 #define ECRYPTFS_MIN_PKT_LEN_SIZE 1 /* Min size to specify packet length */
155 #define ECRYPTFS_MAX_PKT_LEN_SIZE 2 /* Pass at least this many bytes to
156 				     * ecryptfs_parse_packet_length() and
157 				     * ecryptfs_write_packet_length()
158 				     */
159 /* Constraint: ECRYPTFS_FILENAME_MIN_RANDOM_PREPEND_BYTES >=
160  * ECRYPTFS_MAX_IV_BYTES */
161 #define ECRYPTFS_FILENAME_MIN_RANDOM_PREPEND_BYTES 16
162 #define ECRYPTFS_NON_NULL 0x42 /* A reasonable substitute for NULL */
163 #define MD5_DIGEST_SIZE 16
164 #define ECRYPTFS_TAG_70_DIGEST_SIZE MD5_DIGEST_SIZE
165 #define ECRYPTFS_TAG_70_MIN_METADATA_SIZE (1 + ECRYPTFS_MIN_PKT_LEN_SIZE \
166 					   + ECRYPTFS_SIG_SIZE + 1 + 1)
167 #define ECRYPTFS_TAG_70_MAX_METADATA_SIZE (1 + ECRYPTFS_MAX_PKT_LEN_SIZE \
168 					   + ECRYPTFS_SIG_SIZE + 1 + 1)
169 #define ECRYPTFS_FEK_ENCRYPTED_FILENAME_PREFIX "ECRYPTFS_FEK_ENCRYPTED."
170 #define ECRYPTFS_FEK_ENCRYPTED_FILENAME_PREFIX_SIZE 23
171 #define ECRYPTFS_FNEK_ENCRYPTED_FILENAME_PREFIX "ECRYPTFS_FNEK_ENCRYPTED."
172 #define ECRYPTFS_FNEK_ENCRYPTED_FILENAME_PREFIX_SIZE 24
173 #define ECRYPTFS_ENCRYPTED_DENTRY_NAME_LEN (18 + 1 + 4 + 1 + 32)
174 
175 #ifdef CONFIG_ECRYPT_FS_MESSAGING
176 # define ECRYPTFS_VERSIONING_MASK_MESSAGING (ECRYPTFS_VERSIONING_DEVMISC \
177 					     | ECRYPTFS_VERSIONING_PUBKEY)
178 #else
179 # define ECRYPTFS_VERSIONING_MASK_MESSAGING 0
180 #endif
181 
182 #define ECRYPTFS_VERSIONING_MASK (ECRYPTFS_VERSIONING_PASSPHRASE \
183 				  | ECRYPTFS_VERSIONING_PLAINTEXT_PASSTHROUGH \
184 				  | ECRYPTFS_VERSIONING_XATTR \
185 				  | ECRYPTFS_VERSIONING_MULTKEY \
186 				  | ECRYPTFS_VERSIONING_MASK_MESSAGING \
187 				  | ECRYPTFS_VERSIONING_FILENAME_ENCRYPTION)
188 struct ecryptfs_key_sig {
189 	struct list_head crypt_stat_list;
190 	char keysig[ECRYPTFS_SIG_SIZE_HEX + 1];
191 };
192 
193 struct ecryptfs_filename {
194 	struct list_head crypt_stat_list;
195 #define ECRYPTFS_FILENAME_CONTAINS_DECRYPTED 0x00000001
196 	u32 flags;
197 	u32 seq_no;
198 	char *filename;
199 	char *encrypted_filename;
200 	size_t filename_size;
201 	size_t encrypted_filename_size;
202 	char fnek_sig[ECRYPTFS_SIG_SIZE_HEX];
203 	char dentry_name[ECRYPTFS_ENCRYPTED_DENTRY_NAME_LEN + 1];
204 };
205 
206 /**
207  * This is the primary struct associated with each encrypted file.
208  *
209  * TODO: cache align/pack?
210  */
211 struct ecryptfs_crypt_stat {
212 #define ECRYPTFS_STRUCT_INITIALIZED   0x00000001
213 #define ECRYPTFS_POLICY_APPLIED       0x00000002
214 #define ECRYPTFS_ENCRYPTED            0x00000004
215 #define ECRYPTFS_SECURITY_WARNING     0x00000008
216 #define ECRYPTFS_ENABLE_HMAC          0x00000010
217 #define ECRYPTFS_ENCRYPT_IV_PAGES     0x00000020
218 #define ECRYPTFS_KEY_VALID            0x00000040
219 #define ECRYPTFS_METADATA_IN_XATTR    0x00000080
220 #define ECRYPTFS_VIEW_AS_ENCRYPTED    0x00000100
221 #define ECRYPTFS_KEY_SET              0x00000200
222 #define ECRYPTFS_ENCRYPT_FILENAMES    0x00000400
223 #define ECRYPTFS_ENCFN_USE_MOUNT_FNEK 0x00000800
224 #define ECRYPTFS_ENCFN_USE_FEK        0x00001000
225 #define ECRYPTFS_UNLINK_SIGS          0x00002000
226 #define ECRYPTFS_I_SIZE_INITIALIZED   0x00004000
227 	u32 flags;
228 	unsigned int file_version;
229 	size_t iv_bytes;
230 	size_t metadata_size;
231 	size_t extent_size; /* Data extent size; default is 4096 */
232 	size_t key_size;
233 	size_t extent_shift;
234 	unsigned int extent_mask;
235 	struct ecryptfs_mount_crypt_stat *mount_crypt_stat;
236 	struct crypto_skcipher *tfm;
237 	struct crypto_shash *hash_tfm; /* Crypto context for generating
238 					* the initialization vectors */
239 	unsigned char cipher[ECRYPTFS_MAX_CIPHER_NAME_SIZE + 1];
240 	unsigned char key[ECRYPTFS_MAX_KEY_BYTES];
241 	unsigned char root_iv[ECRYPTFS_MAX_IV_BYTES];
242 	struct list_head keysig_list;
243 	struct mutex keysig_list_mutex;
244 	struct mutex cs_tfm_mutex;
245 	struct mutex cs_mutex;
246 };
247 
248 /* inode private data. */
249 struct ecryptfs_inode_info {
250 	struct inode vfs_inode;
251 	struct inode *wii_inode;
252 	struct mutex lower_file_mutex;
253 	atomic_t lower_file_count;
254 	struct file *lower_file;
255 	struct ecryptfs_crypt_stat crypt_stat;
256 };
257 
258 /* dentry private data. Each dentry must keep track of a lower
259  * vfsmount too. */
260 struct ecryptfs_dentry_info {
261 	struct path lower_path;
262 	union {
263 		struct ecryptfs_crypt_stat *crypt_stat;
264 		struct rcu_head rcu;
265 	};
266 };
267 
268 /**
269  * ecryptfs_global_auth_tok - A key used to encrypt all new files under the mountpoint
270  * @flags: Status flags
271  * @mount_crypt_stat_list: These auth_toks hang off the mount-wide
272  *                         cryptographic context. Every time a new
273  *                         inode comes into existence, eCryptfs copies
274  *                         the auth_toks on that list to the set of
275  *                         auth_toks on the inode's crypt_stat
276  * @global_auth_tok_key: The key from the user's keyring for the sig
277  * @global_auth_tok: The key contents
278  * @sig: The key identifier
279  *
280  * ecryptfs_global_auth_tok structs refer to authentication token keys
281  * in the user keyring that apply to newly created files. A list of
282  * these objects hangs off of the mount_crypt_stat struct for any
283  * given eCryptfs mount. This struct maintains a reference to both the
284  * key contents and the key itself so that the key can be put on
285  * unmount.
286  */
287 struct ecryptfs_global_auth_tok {
288 #define ECRYPTFS_AUTH_TOK_INVALID 0x00000001
289 #define ECRYPTFS_AUTH_TOK_FNEK    0x00000002
290 	u32 flags;
291 	struct list_head mount_crypt_stat_list;
292 	struct key *global_auth_tok_key;
293 	unsigned char sig[ECRYPTFS_SIG_SIZE_HEX + 1];
294 };
295 
296 /**
297  * ecryptfs_key_tfm - Persistent key tfm
298  * @key_tfm: crypto API handle to the key
299  * @key_size: Key size in bytes
300  * @key_tfm_mutex: Mutex to ensure only one operation in eCryptfs is
301  *                 using the persistent TFM at any point in time
302  * @key_tfm_list: Handle to hang this off the module-wide TFM list
303  * @cipher_name: String name for the cipher for this TFM
304  *
305  * Typically, eCryptfs will use the same ciphers repeatedly throughout
306  * the course of its operations. In order to avoid unnecessarily
307  * destroying and initializing the same cipher repeatedly, eCryptfs
308  * keeps a list of crypto API contexts around to use when needed.
309  */
310 struct ecryptfs_key_tfm {
311 	struct crypto_skcipher *key_tfm;
312 	size_t key_size;
313 	struct mutex key_tfm_mutex;
314 	struct list_head key_tfm_list;
315 	unsigned char cipher_name[ECRYPTFS_MAX_CIPHER_NAME_SIZE + 1];
316 };
317 
318 extern struct mutex key_tfm_list_mutex;
319 
320 /**
321  * This struct is to enable a mount-wide passphrase/salt combo. This
322  * is more or less a stopgap to provide similar functionality to other
323  * crypto filesystems like EncFS or CFS until full policy support is
324  * implemented in eCryptfs.
325  */
326 struct ecryptfs_mount_crypt_stat {
327 	/* Pointers to memory we do not own, do not free these */
328 #define ECRYPTFS_PLAINTEXT_PASSTHROUGH_ENABLED 0x00000001
329 #define ECRYPTFS_XATTR_METADATA_ENABLED        0x00000002
330 #define ECRYPTFS_ENCRYPTED_VIEW_ENABLED        0x00000004
331 #define ECRYPTFS_MOUNT_CRYPT_STAT_INITIALIZED  0x00000008
332 #define ECRYPTFS_GLOBAL_ENCRYPT_FILENAMES      0x00000010
333 #define ECRYPTFS_GLOBAL_ENCFN_USE_MOUNT_FNEK   0x00000020
334 #define ECRYPTFS_GLOBAL_ENCFN_USE_FEK          0x00000040
335 #define ECRYPTFS_GLOBAL_MOUNT_AUTH_TOK_ONLY    0x00000080
336 	u32 flags;
337 	struct list_head global_auth_tok_list;
338 	struct mutex global_auth_tok_list_mutex;
339 	size_t global_default_cipher_key_size;
340 	size_t global_default_fn_cipher_key_bytes;
341 	unsigned char global_default_cipher_name[ECRYPTFS_MAX_CIPHER_NAME_SIZE
342 						 + 1];
343 	unsigned char global_default_fn_cipher_name[
344 		ECRYPTFS_MAX_CIPHER_NAME_SIZE + 1];
345 	char global_default_fnek_sig[ECRYPTFS_SIG_SIZE_HEX + 1];
346 };
347 
348 /* superblock private data. */
349 struct ecryptfs_sb_info {
350 	struct super_block *wsi_sb;
351 	struct ecryptfs_mount_crypt_stat mount_crypt_stat;
352 	struct backing_dev_info bdi;
353 };
354 
355 /* file private data. */
356 struct ecryptfs_file_info {
357 	struct file *wfi_file;
358 	struct ecryptfs_crypt_stat *crypt_stat;
359 };
360 
361 /* auth_tok <=> encrypted_session_key mappings */
362 struct ecryptfs_auth_tok_list_item {
363 	unsigned char encrypted_session_key[ECRYPTFS_MAX_KEY_BYTES];
364 	struct list_head list;
365 	struct ecryptfs_auth_tok auth_tok;
366 };
367 
368 struct ecryptfs_message {
369 	/* Can never be greater than ecryptfs_message_buf_len */
370 	/* Used to find the parent msg_ctx */
371 	/* Inherits from msg_ctx->index */
372 	u32 index;
373 	u32 data_len;
374 	u8 data[];
375 };
376 
377 struct ecryptfs_msg_ctx {
378 #define ECRYPTFS_MSG_CTX_STATE_FREE     0x01
379 #define ECRYPTFS_MSG_CTX_STATE_PENDING  0x02
380 #define ECRYPTFS_MSG_CTX_STATE_DONE     0x03
381 #define ECRYPTFS_MSG_CTX_STATE_NO_REPLY 0x04
382 	u8 state;
383 #define ECRYPTFS_MSG_HELO 100
384 #define ECRYPTFS_MSG_QUIT 101
385 #define ECRYPTFS_MSG_REQUEST 102
386 #define ECRYPTFS_MSG_RESPONSE 103
387 	u8 type;
388 	u32 index;
389 	/* Counter converts to a sequence number. Each message sent
390 	 * out for which we expect a response has an associated
391 	 * sequence number. The response must have the same sequence
392 	 * number as the counter for the msg_stc for the message to be
393 	 * valid. */
394 	u32 counter;
395 	size_t msg_size;
396 	struct ecryptfs_message *msg;
397 	struct task_struct *task;
398 	struct list_head node;
399 	struct list_head daemon_out_list;
400 	struct mutex mux;
401 };
402 
403 struct ecryptfs_daemon {
404 #define ECRYPTFS_DAEMON_IN_READ      0x00000001
405 #define ECRYPTFS_DAEMON_IN_POLL      0x00000002
406 #define ECRYPTFS_DAEMON_ZOMBIE       0x00000004
407 #define ECRYPTFS_DAEMON_MISCDEV_OPEN 0x00000008
408 	u32 flags;
409 	u32 num_queued_msg_ctx;
410 	struct file *file;
411 	struct mutex mux;
412 	struct list_head msg_ctx_out_queue;
413 	wait_queue_head_t wait;
414 	struct hlist_node euid_chain;
415 };
416 
417 #ifdef CONFIG_ECRYPT_FS_MESSAGING
418 extern struct mutex ecryptfs_daemon_hash_mux;
419 #endif
420 
421 static inline size_t
422 ecryptfs_lower_header_size(struct ecryptfs_crypt_stat *crypt_stat)
423 {
424 	if (crypt_stat->flags & ECRYPTFS_METADATA_IN_XATTR)
425 		return 0;
426 	return crypt_stat->metadata_size;
427 }
428 
429 static inline struct ecryptfs_file_info *
430 ecryptfs_file_to_private(struct file *file)
431 {
432 	return file->private_data;
433 }
434 
435 static inline void
436 ecryptfs_set_file_private(struct file *file,
437 			  struct ecryptfs_file_info *file_info)
438 {
439 	file->private_data = file_info;
440 }
441 
442 static inline struct file *ecryptfs_file_to_lower(struct file *file)
443 {
444 	return ((struct ecryptfs_file_info *)file->private_data)->wfi_file;
445 }
446 
447 static inline void
448 ecryptfs_set_file_lower(struct file *file, struct file *lower_file)
449 {
450 	((struct ecryptfs_file_info *)file->private_data)->wfi_file =
451 		lower_file;
452 }
453 
454 static inline struct ecryptfs_inode_info *
455 ecryptfs_inode_to_private(struct inode *inode)
456 {
457 	return container_of(inode, struct ecryptfs_inode_info, vfs_inode);
458 }
459 
460 static inline struct inode *ecryptfs_inode_to_lower(struct inode *inode)
461 {
462 	return ecryptfs_inode_to_private(inode)->wii_inode;
463 }
464 
465 static inline void
466 ecryptfs_set_inode_lower(struct inode *inode, struct inode *lower_inode)
467 {
468 	ecryptfs_inode_to_private(inode)->wii_inode = lower_inode;
469 }
470 
471 static inline struct ecryptfs_sb_info *
472 ecryptfs_superblock_to_private(struct super_block *sb)
473 {
474 	return (struct ecryptfs_sb_info *)sb->s_fs_info;
475 }
476 
477 static inline void
478 ecryptfs_set_superblock_private(struct super_block *sb,
479 				struct ecryptfs_sb_info *sb_info)
480 {
481 	sb->s_fs_info = sb_info;
482 }
483 
484 static inline struct super_block *
485 ecryptfs_superblock_to_lower(struct super_block *sb)
486 {
487 	return ((struct ecryptfs_sb_info *)sb->s_fs_info)->wsi_sb;
488 }
489 
490 static inline void
491 ecryptfs_set_superblock_lower(struct super_block *sb,
492 			      struct super_block *lower_sb)
493 {
494 	((struct ecryptfs_sb_info *)sb->s_fs_info)->wsi_sb = lower_sb;
495 }
496 
497 static inline struct ecryptfs_dentry_info *
498 ecryptfs_dentry_to_private(struct dentry *dentry)
499 {
500 	return (struct ecryptfs_dentry_info *)dentry->d_fsdata;
501 }
502 
503 static inline void
504 ecryptfs_set_dentry_private(struct dentry *dentry,
505 			    struct ecryptfs_dentry_info *dentry_info)
506 {
507 	dentry->d_fsdata = dentry_info;
508 }
509 
510 static inline struct dentry *
511 ecryptfs_dentry_to_lower(struct dentry *dentry)
512 {
513 	return ((struct ecryptfs_dentry_info *)dentry->d_fsdata)->lower_path.dentry;
514 }
515 
516 static inline struct vfsmount *
517 ecryptfs_dentry_to_lower_mnt(struct dentry *dentry)
518 {
519 	return ((struct ecryptfs_dentry_info *)dentry->d_fsdata)->lower_path.mnt;
520 }
521 
522 static inline struct path *
523 ecryptfs_dentry_to_lower_path(struct dentry *dentry)
524 {
525 	return &((struct ecryptfs_dentry_info *)dentry->d_fsdata)->lower_path;
526 }
527 
528 #define ecryptfs_printk(type, fmt, arg...) \
529         __ecryptfs_printk(type "%s: " fmt, __func__, ## arg);
530 __printf(1, 2)
531 void __ecryptfs_printk(const char *fmt, ...);
532 
533 extern const struct file_operations ecryptfs_main_fops;
534 extern const struct file_operations ecryptfs_dir_fops;
535 extern const struct inode_operations ecryptfs_main_iops;
536 extern const struct inode_operations ecryptfs_dir_iops;
537 extern const struct inode_operations ecryptfs_symlink_iops;
538 extern const struct super_operations ecryptfs_sops;
539 extern const struct dentry_operations ecryptfs_dops;
540 extern const struct address_space_operations ecryptfs_aops;
541 extern int ecryptfs_verbosity;
542 extern unsigned int ecryptfs_message_buf_len;
543 extern signed long ecryptfs_message_wait_timeout;
544 extern unsigned int ecryptfs_number_of_users;
545 
546 extern struct kmem_cache *ecryptfs_auth_tok_list_item_cache;
547 extern struct kmem_cache *ecryptfs_file_info_cache;
548 extern struct kmem_cache *ecryptfs_dentry_info_cache;
549 extern struct kmem_cache *ecryptfs_inode_info_cache;
550 extern struct kmem_cache *ecryptfs_sb_info_cache;
551 extern struct kmem_cache *ecryptfs_header_cache;
552 extern struct kmem_cache *ecryptfs_xattr_cache;
553 extern struct kmem_cache *ecryptfs_key_record_cache;
554 extern struct kmem_cache *ecryptfs_key_sig_cache;
555 extern struct kmem_cache *ecryptfs_global_auth_tok_cache;
556 extern struct kmem_cache *ecryptfs_key_tfm_cache;
557 
558 struct inode *ecryptfs_get_inode(struct inode *lower_inode,
559 				 struct super_block *sb);
560 void ecryptfs_i_size_init(const char *page_virt, struct inode *inode);
561 int ecryptfs_initialize_file(struct dentry *ecryptfs_dentry,
562 			     struct inode *ecryptfs_inode);
563 int ecryptfs_decode_and_decrypt_filename(char **decrypted_name,
564 					 size_t *decrypted_name_size,
565 					 struct super_block *sb,
566 					 const char *name, size_t name_size);
567 int ecryptfs_fill_zeros(struct file *file, loff_t new_length);
568 int ecryptfs_encrypt_and_encode_filename(
569 	char **encoded_name,
570 	size_t *encoded_name_size,
571 	struct ecryptfs_mount_crypt_stat *mount_crypt_stat,
572 	const char *name, size_t name_size);
573 struct dentry *ecryptfs_lower_dentry(struct dentry *this_dentry);
574 void ecryptfs_dump_hex(char *data, int bytes);
575 int virt_to_scatterlist(const void *addr, int size, struct scatterlist *sg,
576 			int sg_size);
577 int ecryptfs_compute_root_iv(struct ecryptfs_crypt_stat *crypt_stat);
578 void ecryptfs_rotate_iv(unsigned char *iv);
579 int ecryptfs_init_crypt_stat(struct ecryptfs_crypt_stat *crypt_stat);
580 void ecryptfs_destroy_crypt_stat(struct ecryptfs_crypt_stat *crypt_stat);
581 void ecryptfs_destroy_mount_crypt_stat(
582 	struct ecryptfs_mount_crypt_stat *mount_crypt_stat);
583 int ecryptfs_init_crypt_ctx(struct ecryptfs_crypt_stat *crypt_stat);
584 int ecryptfs_write_inode_size_to_metadata(struct inode *ecryptfs_inode);
585 int ecryptfs_encrypt_page(struct page *page);
586 int ecryptfs_decrypt_page(struct page *page);
587 int ecryptfs_write_metadata(struct dentry *ecryptfs_dentry,
588 			    struct inode *ecryptfs_inode);
589 int ecryptfs_read_metadata(struct dentry *ecryptfs_dentry);
590 int ecryptfs_new_file_context(struct inode *ecryptfs_inode);
591 void ecryptfs_write_crypt_stat_flags(char *page_virt,
592 				     struct ecryptfs_crypt_stat *crypt_stat,
593 				     size_t *written);
594 int ecryptfs_read_and_validate_header_region(struct inode *inode);
595 int ecryptfs_read_and_validate_xattr_region(struct dentry *dentry,
596 					    struct inode *inode);
597 u8 ecryptfs_code_for_cipher_string(char *cipher_name, size_t key_bytes);
598 int ecryptfs_cipher_code_to_string(char *str, u8 cipher_code);
599 void ecryptfs_set_default_sizes(struct ecryptfs_crypt_stat *crypt_stat);
600 int ecryptfs_generate_key_packet_set(char *dest_base,
601 				     struct ecryptfs_crypt_stat *crypt_stat,
602 				     struct dentry *ecryptfs_dentry,
603 				     size_t *len, size_t max);
604 int
605 ecryptfs_parse_packet_set(struct ecryptfs_crypt_stat *crypt_stat,
606 			  unsigned char *src, struct dentry *ecryptfs_dentry);
607 int ecryptfs_truncate(struct dentry *dentry, loff_t new_length);
608 ssize_t
609 ecryptfs_getxattr_lower(struct dentry *lower_dentry, struct inode *lower_inode,
610 			const char *name, void *value, size_t size);
611 int
612 ecryptfs_setxattr(struct dentry *dentry, struct inode *inode, const char *name,
613 		  const void *value, size_t size, int flags);
614 int ecryptfs_read_xattr_region(char *page_virt, struct inode *ecryptfs_inode);
615 #ifdef CONFIG_ECRYPT_FS_MESSAGING
616 int ecryptfs_process_response(struct ecryptfs_daemon *daemon,
617 			      struct ecryptfs_message *msg, u32 seq);
618 int ecryptfs_send_message(char *data, int data_len,
619 			  struct ecryptfs_msg_ctx **msg_ctx);
620 int ecryptfs_wait_for_response(struct ecryptfs_msg_ctx *msg_ctx,
621 			       struct ecryptfs_message **emsg);
622 int ecryptfs_init_messaging(void);
623 void ecryptfs_release_messaging(void);
624 #else
625 static inline int ecryptfs_init_messaging(void)
626 {
627 	return 0;
628 }
629 static inline void ecryptfs_release_messaging(void)
630 { }
631 static inline int ecryptfs_send_message(char *data, int data_len,
632 					struct ecryptfs_msg_ctx **msg_ctx)
633 {
634 	return -ENOTCONN;
635 }
636 static inline int ecryptfs_wait_for_response(struct ecryptfs_msg_ctx *msg_ctx,
637 					     struct ecryptfs_message **emsg)
638 {
639 	return -ENOMSG;
640 }
641 #endif
642 
643 void
644 ecryptfs_write_header_metadata(char *virt,
645 			       struct ecryptfs_crypt_stat *crypt_stat,
646 			       size_t *written);
647 int ecryptfs_add_keysig(struct ecryptfs_crypt_stat *crypt_stat, char *sig);
648 int
649 ecryptfs_add_global_auth_tok(struct ecryptfs_mount_crypt_stat *mount_crypt_stat,
650 			   char *sig, u32 global_auth_tok_flags);
651 int ecryptfs_get_global_auth_tok_for_sig(
652 	struct ecryptfs_global_auth_tok **global_auth_tok,
653 	struct ecryptfs_mount_crypt_stat *mount_crypt_stat, char *sig);
654 int
655 ecryptfs_add_new_key_tfm(struct ecryptfs_key_tfm **key_tfm, char *cipher_name,
656 			 size_t key_size);
657 int ecryptfs_init_crypto(void);
658 int ecryptfs_destroy_crypto(void);
659 int ecryptfs_tfm_exists(char *cipher_name, struct ecryptfs_key_tfm **key_tfm);
660 int ecryptfs_get_tfm_and_mutex_for_cipher_name(struct crypto_skcipher **tfm,
661 					       struct mutex **tfm_mutex,
662 					       char *cipher_name);
663 int ecryptfs_keyring_auth_tok_for_sig(struct key **auth_tok_key,
664 				      struct ecryptfs_auth_tok **auth_tok,
665 				      char *sig);
666 int ecryptfs_write_lower(struct inode *ecryptfs_inode, char *data,
667 			 loff_t offset, size_t size);
668 int ecryptfs_write_lower_page_segment(struct inode *ecryptfs_inode,
669 				      struct page *page_for_lower,
670 				      size_t offset_in_page, size_t size);
671 int ecryptfs_write(struct inode *inode, char *data, loff_t offset, size_t size);
672 int ecryptfs_read_lower(char *data, loff_t offset, size_t size,
673 			struct inode *ecryptfs_inode);
674 int ecryptfs_read_lower_page_segment(struct page *page_for_ecryptfs,
675 				     pgoff_t page_index,
676 				     size_t offset_in_page, size_t size,
677 				     struct inode *ecryptfs_inode);
678 struct page *ecryptfs_get_locked_page(struct inode *inode, loff_t index);
679 int ecryptfs_parse_packet_length(unsigned char *data, size_t *size,
680 				 size_t *length_size);
681 int ecryptfs_write_packet_length(char *dest, size_t size,
682 				 size_t *packet_size_length);
683 #ifdef CONFIG_ECRYPT_FS_MESSAGING
684 int ecryptfs_init_ecryptfs_miscdev(void);
685 void ecryptfs_destroy_ecryptfs_miscdev(void);
686 int ecryptfs_send_miscdev(char *data, size_t data_size,
687 			  struct ecryptfs_msg_ctx *msg_ctx, u8 msg_type,
688 			  u16 msg_flags, struct ecryptfs_daemon *daemon);
689 void ecryptfs_msg_ctx_alloc_to_free(struct ecryptfs_msg_ctx *msg_ctx);
690 int
691 ecryptfs_spawn_daemon(struct ecryptfs_daemon **daemon, struct file *file);
692 int ecryptfs_exorcise_daemon(struct ecryptfs_daemon *daemon);
693 int ecryptfs_find_daemon_by_euid(struct ecryptfs_daemon **daemon);
694 #endif
695 int ecryptfs_init_kthread(void);
696 void ecryptfs_destroy_kthread(void);
697 int ecryptfs_privileged_open(struct file **lower_file,
698 			     struct dentry *lower_dentry,
699 			     struct vfsmount *lower_mnt,
700 			     const struct cred *cred);
701 int ecryptfs_get_lower_file(struct dentry *dentry, struct inode *inode);
702 void ecryptfs_put_lower_file(struct inode *inode);
703 int
704 ecryptfs_write_tag_70_packet(char *dest, size_t *remaining_bytes,
705 			     size_t *packet_size,
706 			     struct ecryptfs_mount_crypt_stat *mount_crypt_stat,
707 			     char *filename, size_t filename_size);
708 int
709 ecryptfs_parse_tag_70_packet(char **filename, size_t *filename_size,
710 			     size_t *packet_size,
711 			     struct ecryptfs_mount_crypt_stat *mount_crypt_stat,
712 			     char *data, size_t max_packet_size);
713 int ecryptfs_set_f_namelen(long *namelen, long lower_namelen,
714 			   struct ecryptfs_mount_crypt_stat *mount_crypt_stat);
715 int ecryptfs_derive_iv(char *iv, struct ecryptfs_crypt_stat *crypt_stat,
716 		       loff_t offset);
717 
718 #endif /* #ifndef ECRYPTFS_KERNEL_H */
719