xref: /openbmc/linux/fs/ecryptfs/ecryptfs_kernel.h (revision 9c79f34f7ee71cd28272332b424ca64b2be006ab)
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 <linux/fs.h>
33 #include <linux/fs_stack.h>
34 #include <linux/namei.h>
35 #include <linux/scatterlist.h>
36 #include <linux/hash.h>
37 #include <linux/nsproxy.h>
38 
39 /* Version verification for shared data structures w/ userspace */
40 #define ECRYPTFS_VERSION_MAJOR 0x00
41 #define ECRYPTFS_VERSION_MINOR 0x04
42 #define ECRYPTFS_SUPPORTED_FILE_VERSION 0x03
43 /* These flags indicate which features are supported by the kernel
44  * module; userspace tools such as the mount helper read
45  * ECRYPTFS_VERSIONING_MASK from a sysfs handle in order to determine
46  * how to behave. */
47 #define ECRYPTFS_VERSIONING_PASSPHRASE            0x00000001
48 #define ECRYPTFS_VERSIONING_PUBKEY                0x00000002
49 #define ECRYPTFS_VERSIONING_PLAINTEXT_PASSTHROUGH 0x00000004
50 #define ECRYPTFS_VERSIONING_POLICY                0x00000008
51 #define ECRYPTFS_VERSIONING_XATTR                 0x00000010
52 #define ECRYPTFS_VERSIONING_MULTKEY               0x00000020
53 #define ECRYPTFS_VERSIONING_DEVMISC               0x00000040
54 #define ECRYPTFS_VERSIONING_MASK (ECRYPTFS_VERSIONING_PASSPHRASE \
55 				  | ECRYPTFS_VERSIONING_PLAINTEXT_PASSTHROUGH \
56 				  | ECRYPTFS_VERSIONING_PUBKEY \
57 				  | ECRYPTFS_VERSIONING_XATTR \
58 				  | ECRYPTFS_VERSIONING_MULTKEY \
59 				  | ECRYPTFS_VERSIONING_DEVMISC)
60 #define ECRYPTFS_MAX_PASSWORD_LENGTH 64
61 #define ECRYPTFS_MAX_PASSPHRASE_BYTES ECRYPTFS_MAX_PASSWORD_LENGTH
62 #define ECRYPTFS_SALT_SIZE 8
63 #define ECRYPTFS_SALT_SIZE_HEX (ECRYPTFS_SALT_SIZE*2)
64 /* The original signature size is only for what is stored on disk; all
65  * in-memory representations are expanded hex, so it better adapted to
66  * be passed around or referenced on the command line */
67 #define ECRYPTFS_SIG_SIZE 8
68 #define ECRYPTFS_SIG_SIZE_HEX (ECRYPTFS_SIG_SIZE*2)
69 #define ECRYPTFS_PASSWORD_SIG_SIZE ECRYPTFS_SIG_SIZE_HEX
70 #define ECRYPTFS_MAX_KEY_BYTES 64
71 #define ECRYPTFS_MAX_ENCRYPTED_KEY_BYTES 512
72 #define ECRYPTFS_DEFAULT_IV_BYTES 16
73 #define ECRYPTFS_FILE_VERSION 0x03
74 #define ECRYPTFS_DEFAULT_EXTENT_SIZE 4096
75 #define ECRYPTFS_MINIMUM_HEADER_EXTENT_SIZE 8192
76 #define ECRYPTFS_DEFAULT_MSG_CTX_ELEMS 32
77 #define ECRYPTFS_DEFAULT_SEND_TIMEOUT HZ
78 #define ECRYPTFS_MAX_MSG_CTX_TTL (HZ*3)
79 #define ECRYPTFS_MAX_PKI_NAME_BYTES 16
80 #define ECRYPTFS_DEFAULT_NUM_USERS 4
81 #define ECRYPTFS_MAX_NUM_USERS 32768
82 #define ECRYPTFS_XATTR_NAME "user.ecryptfs"
83 
84 #define RFC2440_CIPHER_DES3_EDE 0x02
85 #define RFC2440_CIPHER_CAST_5 0x03
86 #define RFC2440_CIPHER_BLOWFISH 0x04
87 #define RFC2440_CIPHER_AES_128 0x07
88 #define RFC2440_CIPHER_AES_192 0x08
89 #define RFC2440_CIPHER_AES_256 0x09
90 #define RFC2440_CIPHER_TWOFISH 0x0a
91 #define RFC2440_CIPHER_CAST_6 0x0b
92 
93 #define RFC2440_CIPHER_RSA 0x01
94 
95 /**
96  * For convenience, we may need to pass around the encrypted session
97  * key between kernel and userspace because the authentication token
98  * may not be extractable.  For example, the TPM may not release the
99  * private key, instead requiring the encrypted data and returning the
100  * decrypted data.
101  */
102 struct ecryptfs_session_key {
103 #define ECRYPTFS_USERSPACE_SHOULD_TRY_TO_DECRYPT 0x00000001
104 #define ECRYPTFS_USERSPACE_SHOULD_TRY_TO_ENCRYPT 0x00000002
105 #define ECRYPTFS_CONTAINS_DECRYPTED_KEY 0x00000004
106 #define ECRYPTFS_CONTAINS_ENCRYPTED_KEY 0x00000008
107 	u32 flags;
108 	u32 encrypted_key_size;
109 	u32 decrypted_key_size;
110 	u8 encrypted_key[ECRYPTFS_MAX_ENCRYPTED_KEY_BYTES];
111 	u8 decrypted_key[ECRYPTFS_MAX_KEY_BYTES];
112 };
113 
114 struct ecryptfs_password {
115 	u32 password_bytes;
116 	s32 hash_algo;
117 	u32 hash_iterations;
118 	u32 session_key_encryption_key_bytes;
119 #define ECRYPTFS_PERSISTENT_PASSWORD 0x01
120 #define ECRYPTFS_SESSION_KEY_ENCRYPTION_KEY_SET 0x02
121 	u32 flags;
122 	/* Iterated-hash concatenation of salt and passphrase */
123 	u8 session_key_encryption_key[ECRYPTFS_MAX_KEY_BYTES];
124 	u8 signature[ECRYPTFS_PASSWORD_SIG_SIZE + 1];
125 	/* Always in expanded hex */
126 	u8 salt[ECRYPTFS_SALT_SIZE];
127 };
128 
129 enum ecryptfs_token_types {ECRYPTFS_PASSWORD, ECRYPTFS_PRIVATE_KEY};
130 
131 struct ecryptfs_private_key {
132 	u32 key_size;
133 	u32 data_len;
134 	u8 signature[ECRYPTFS_PASSWORD_SIG_SIZE + 1];
135 	char pki_type[ECRYPTFS_MAX_PKI_NAME_BYTES + 1];
136 	u8 data[];
137 };
138 
139 /* May be a password or a private key */
140 struct ecryptfs_auth_tok {
141 	u16 version; /* 8-bit major and 8-bit minor */
142 	u16 token_type;
143 #define ECRYPTFS_ENCRYPT_ONLY 0x00000001
144 	u32 flags;
145 	struct ecryptfs_session_key session_key;
146 	u8 reserved[32];
147 	union {
148 		struct ecryptfs_password password;
149 		struct ecryptfs_private_key private_key;
150 	} token;
151 } __attribute__ ((packed));
152 
153 void ecryptfs_dump_auth_tok(struct ecryptfs_auth_tok *auth_tok);
154 extern void ecryptfs_to_hex(char *dst, char *src, size_t src_size);
155 extern void ecryptfs_from_hex(char *dst, char *src, int dst_size);
156 
157 struct ecryptfs_key_record {
158 	unsigned char type;
159 	size_t enc_key_size;
160 	unsigned char sig[ECRYPTFS_SIG_SIZE];
161 	unsigned char enc_key[ECRYPTFS_MAX_ENCRYPTED_KEY_BYTES];
162 };
163 
164 struct ecryptfs_auth_tok_list {
165 	struct ecryptfs_auth_tok *auth_tok;
166 	struct list_head list;
167 };
168 
169 struct ecryptfs_crypt_stat;
170 struct ecryptfs_mount_crypt_stat;
171 
172 struct ecryptfs_page_crypt_context {
173 	struct page *page;
174 #define ECRYPTFS_PREPARE_COMMIT_MODE 0
175 #define ECRYPTFS_WRITEPAGE_MODE      1
176 	unsigned int mode;
177 	union {
178 		struct file *lower_file;
179 		struct writeback_control *wbc;
180 	} param;
181 };
182 
183 static inline struct ecryptfs_auth_tok *
184 ecryptfs_get_key_payload_data(struct key *key)
185 {
186 	return (struct ecryptfs_auth_tok *)
187 		(((struct user_key_payload*)key->payload.data)->data);
188 }
189 
190 #define ECRYPTFS_SUPER_MAGIC 0xf15f
191 #define ECRYPTFS_MAX_KEYSET_SIZE 1024
192 #define ECRYPTFS_MAX_CIPHER_NAME_SIZE 32
193 #define ECRYPTFS_MAX_NUM_ENC_KEYS 64
194 #define ECRYPTFS_MAX_IV_BYTES 16	/* 128 bits */
195 #define ECRYPTFS_SALT_BYTES 2
196 #define MAGIC_ECRYPTFS_MARKER 0x3c81b7f5
197 #define MAGIC_ECRYPTFS_MARKER_SIZE_BYTES 8	/* 4*2 */
198 #define ECRYPTFS_FILE_SIZE_BYTES (sizeof(u64))
199 #define ECRYPTFS_DEFAULT_CIPHER "aes"
200 #define ECRYPTFS_DEFAULT_KEY_BYTES 16
201 #define ECRYPTFS_DEFAULT_HASH "md5"
202 #define ECRYPTFS_TAG_70_DIGEST ECRYPTFS_DEFAULT_HASH
203 #define ECRYPTFS_TAG_1_PACKET_TYPE 0x01
204 #define ECRYPTFS_TAG_3_PACKET_TYPE 0x8C
205 #define ECRYPTFS_TAG_11_PACKET_TYPE 0xED
206 #define ECRYPTFS_TAG_64_PACKET_TYPE 0x40
207 #define ECRYPTFS_TAG_65_PACKET_TYPE 0x41
208 #define ECRYPTFS_TAG_66_PACKET_TYPE 0x42
209 #define ECRYPTFS_TAG_67_PACKET_TYPE 0x43
210 #define ECRYPTFS_TAG_70_PACKET_TYPE 0x46 /* FNEK-encrypted filename
211 					  * as dentry name */
212 #define ECRYPTFS_TAG_71_PACKET_TYPE 0x47 /* FNEK-encrypted filename in
213 					  * metadata */
214 #define ECRYPTFS_TAG_72_PACKET_TYPE 0x48 /* FEK-encrypted filename as
215 					  * dentry name */
216 #define ECRYPTFS_TAG_73_PACKET_TYPE 0x49 /* FEK-encrypted filename as
217 					  * metadata */
218 /* Constraint: ECRYPTFS_FILENAME_MIN_RANDOM_PREPEND_BYTES >=
219  * ECRYPTFS_MAX_IV_BYTES */
220 #define ECRYPTFS_FILENAME_MIN_RANDOM_PREPEND_BYTES 16
221 #define ECRYPTFS_NON_NULL 0x42 /* A reasonable substitute for NULL */
222 #define MD5_DIGEST_SIZE 16
223 #define ECRYPTFS_TAG_70_DIGEST_SIZE MD5_DIGEST_SIZE
224 #define ECRYPTFS_FEK_ENCRYPTED_FILENAME_PREFIX "ECRYPTFS_FEK_ENCRYPTED."
225 #define ECRYPTFS_FEK_ENCRYPTED_FILENAME_PREFIX_SIZE 23
226 #define ECRYPTFS_FNEK_ENCRYPTED_FILENAME_PREFIX "ECRYPTFS_FNEK_ENCRYPTED."
227 #define ECRYPTFS_FNEK_ENCRYPTED_FILENAME_PREFIX_SIZE 24
228 #define ECRYPTFS_ENCRYPTED_DENTRY_NAME_LEN (18 + 1 + 4 + 1 + 32)
229 
230 struct ecryptfs_key_sig {
231 	struct list_head crypt_stat_list;
232 	char keysig[ECRYPTFS_SIG_SIZE_HEX];
233 };
234 
235 /**
236  * This is the primary struct associated with each encrypted file.
237  *
238  * TODO: cache align/pack?
239  */
240 struct ecryptfs_crypt_stat {
241 #define ECRYPTFS_STRUCT_INITIALIZED 0x00000001
242 #define ECRYPTFS_POLICY_APPLIED     0x00000002
243 #define ECRYPTFS_NEW_FILE           0x00000004
244 #define ECRYPTFS_ENCRYPTED          0x00000008
245 #define ECRYPTFS_SECURITY_WARNING   0x00000010
246 #define ECRYPTFS_ENABLE_HMAC        0x00000020
247 #define ECRYPTFS_ENCRYPT_IV_PAGES   0x00000040
248 #define ECRYPTFS_KEY_VALID          0x00000080
249 #define ECRYPTFS_METADATA_IN_XATTR  0x00000100
250 #define ECRYPTFS_VIEW_AS_ENCRYPTED  0x00000200
251 #define ECRYPTFS_KEY_SET            0x00000400
252 	u32 flags;
253 	unsigned int file_version;
254 	size_t iv_bytes;
255 	size_t num_header_bytes_at_front;
256 	size_t extent_size; /* Data extent size; default is 4096 */
257 	size_t key_size;
258 	size_t extent_shift;
259 	unsigned int extent_mask;
260 	struct ecryptfs_mount_crypt_stat *mount_crypt_stat;
261 	struct crypto_blkcipher *tfm;
262 	struct crypto_hash *hash_tfm; /* Crypto context for generating
263 				       * the initialization vectors */
264 	unsigned char cipher[ECRYPTFS_MAX_CIPHER_NAME_SIZE];
265 	unsigned char key[ECRYPTFS_MAX_KEY_BYTES];
266 	unsigned char root_iv[ECRYPTFS_MAX_IV_BYTES];
267 	struct list_head keysig_list;
268 	struct mutex keysig_list_mutex;
269 	struct mutex cs_tfm_mutex;
270 	struct mutex cs_hash_tfm_mutex;
271 	struct mutex cs_mutex;
272 };
273 
274 /* inode private data. */
275 struct ecryptfs_inode_info {
276 	struct inode vfs_inode;
277 	struct inode *wii_inode;
278 	struct file *lower_file;
279 	struct mutex lower_file_mutex;
280 	struct ecryptfs_crypt_stat crypt_stat;
281 };
282 
283 /* dentry private data. Each dentry must keep track of a lower
284  * vfsmount too. */
285 struct ecryptfs_dentry_info {
286 	struct path lower_path;
287 	struct ecryptfs_crypt_stat *crypt_stat;
288 };
289 
290 /**
291  * ecryptfs_global_auth_tok - A key used to encrypt all new files under the mountpoint
292  * @flags: Status flags
293  * @mount_crypt_stat_list: These auth_toks hang off the mount-wide
294  *                         cryptographic context. Every time a new
295  *                         inode comes into existence, eCryptfs copies
296  *                         the auth_toks on that list to the set of
297  *                         auth_toks on the inode's crypt_stat
298  * @global_auth_tok_key: The key from the user's keyring for the sig
299  * @global_auth_tok: The key contents
300  * @sig: The key identifier
301  *
302  * ecryptfs_global_auth_tok structs refer to authentication token keys
303  * in the user keyring that apply to newly created files. A list of
304  * these objects hangs off of the mount_crypt_stat struct for any
305  * given eCryptfs mount. This struct maintains a reference to both the
306  * key contents and the key itself so that the key can be put on
307  * unmount.
308  */
309 struct ecryptfs_global_auth_tok {
310 #define ECRYPTFS_AUTH_TOK_INVALID 0x00000001
311 	u32 flags;
312 	struct list_head mount_crypt_stat_list;
313 	struct key *global_auth_tok_key;
314 	struct ecryptfs_auth_tok *global_auth_tok;
315 	unsigned char sig[ECRYPTFS_SIG_SIZE_HEX + 1];
316 };
317 
318 /**
319  * ecryptfs_key_tfm - Persistent key tfm
320  * @key_tfm: crypto API handle to the key
321  * @key_size: Key size in bytes
322  * @key_tfm_mutex: Mutex to ensure only one operation in eCryptfs is
323  *                 using the persistent TFM at any point in time
324  * @key_tfm_list: Handle to hang this off the module-wide TFM list
325  * @cipher_name: String name for the cipher for this TFM
326  *
327  * Typically, eCryptfs will use the same ciphers repeatedly throughout
328  * the course of its operations. In order to avoid unnecessarily
329  * destroying and initializing the same cipher repeatedly, eCryptfs
330  * keeps a list of crypto API contexts around to use when needed.
331  */
332 struct ecryptfs_key_tfm {
333 	struct crypto_blkcipher *key_tfm;
334 	size_t key_size;
335 	struct mutex key_tfm_mutex;
336 	struct list_head key_tfm_list;
337 	unsigned char cipher_name[ECRYPTFS_MAX_CIPHER_NAME_SIZE + 1];
338 };
339 
340 extern struct mutex key_tfm_list_mutex;
341 
342 /**
343  * This struct is to enable a mount-wide passphrase/salt combo. This
344  * is more or less a stopgap to provide similar functionality to other
345  * crypto filesystems like EncFS or CFS until full policy support is
346  * implemented in eCryptfs.
347  */
348 struct ecryptfs_mount_crypt_stat {
349 	/* Pointers to memory we do not own, do not free these */
350 #define ECRYPTFS_PLAINTEXT_PASSTHROUGH_ENABLED 0x00000001
351 #define ECRYPTFS_XATTR_METADATA_ENABLED        0x00000002
352 #define ECRYPTFS_ENCRYPTED_VIEW_ENABLED        0x00000004
353 #define ECRYPTFS_MOUNT_CRYPT_STAT_INITIALIZED  0x00000008
354 #define ECRYPTFS_GLOBAL_ENCRYPT_FILENAMES      0x00000010
355 #define ECRYPTFS_GLOBAL_ENCFN_USE_MOUNT_FNEK   0x00000020
356 #define ECRYPTFS_GLOBAL_ENCFN_USE_FEK          0x00000040
357 	u32 flags;
358 	struct list_head global_auth_tok_list;
359 	struct mutex global_auth_tok_list_mutex;
360 	size_t num_global_auth_toks;
361 	size_t global_default_cipher_key_size;
362 	size_t global_default_fn_cipher_key_bytes;
363 	unsigned char global_default_cipher_name[ECRYPTFS_MAX_CIPHER_NAME_SIZE
364 						 + 1];
365 	unsigned char global_default_fn_cipher_name[
366 		ECRYPTFS_MAX_CIPHER_NAME_SIZE + 1];
367 	char global_default_fnek_sig[ECRYPTFS_SIG_SIZE_HEX + 1];
368 };
369 
370 /* superblock private data. */
371 struct ecryptfs_sb_info {
372 	struct super_block *wsi_sb;
373 	struct ecryptfs_mount_crypt_stat mount_crypt_stat;
374 };
375 
376 /* file private data. */
377 struct ecryptfs_file_info {
378 	struct file *wfi_file;
379 	struct ecryptfs_crypt_stat *crypt_stat;
380 };
381 
382 /* auth_tok <=> encrypted_session_key mappings */
383 struct ecryptfs_auth_tok_list_item {
384 	unsigned char encrypted_session_key[ECRYPTFS_MAX_KEY_BYTES];
385 	struct list_head list;
386 	struct ecryptfs_auth_tok auth_tok;
387 };
388 
389 struct ecryptfs_message {
390 	/* Can never be greater than ecryptfs_message_buf_len */
391 	/* Used to find the parent msg_ctx */
392 	/* Inherits from msg_ctx->index */
393 	u32 index;
394 	u32 data_len;
395 	u8 data[];
396 };
397 
398 struct ecryptfs_msg_ctx {
399 #define ECRYPTFS_MSG_CTX_STATE_FREE     0x01
400 #define ECRYPTFS_MSG_CTX_STATE_PENDING  0x02
401 #define ECRYPTFS_MSG_CTX_STATE_DONE     0x03
402 #define ECRYPTFS_MSG_CTX_STATE_NO_REPLY 0x04
403 	u8 state;
404 #define ECRYPTFS_MSG_HELO 100
405 #define ECRYPTFS_MSG_QUIT 101
406 #define ECRYPTFS_MSG_REQUEST 102
407 #define ECRYPTFS_MSG_RESPONSE 103
408 	u8 type;
409 	u32 index;
410 	/* Counter converts to a sequence number. Each message sent
411 	 * out for which we expect a response has an associated
412 	 * sequence number. The response must have the same sequence
413 	 * number as the counter for the msg_stc for the message to be
414 	 * valid. */
415 	u32 counter;
416 	size_t msg_size;
417 	struct ecryptfs_message *msg;
418 	struct task_struct *task;
419 	struct list_head node;
420 	struct list_head daemon_out_list;
421 	struct mutex mux;
422 };
423 
424 struct ecryptfs_daemon;
425 
426 struct ecryptfs_daemon {
427 #define ECRYPTFS_DAEMON_IN_READ      0x00000001
428 #define ECRYPTFS_DAEMON_IN_POLL      0x00000002
429 #define ECRYPTFS_DAEMON_ZOMBIE       0x00000004
430 #define ECRYPTFS_DAEMON_MISCDEV_OPEN 0x00000008
431 	u32 flags;
432 	u32 num_queued_msg_ctx;
433 	struct pid *pid;
434 	uid_t euid;
435 	struct user_namespace *user_ns;
436 	struct task_struct *task;
437 	struct mutex mux;
438 	struct list_head msg_ctx_out_queue;
439 	wait_queue_head_t wait;
440 	struct hlist_node euid_chain;
441 };
442 
443 extern struct mutex ecryptfs_daemon_hash_mux;
444 
445 static inline struct ecryptfs_file_info *
446 ecryptfs_file_to_private(struct file *file)
447 {
448 	return (struct ecryptfs_file_info *)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 void
533 ecryptfs_set_dentry_lower(struct dentry *dentry, struct dentry *lower_dentry)
534 {
535 	((struct ecryptfs_dentry_info *)dentry->d_fsdata)->lower_path.dentry =
536 		lower_dentry;
537 }
538 
539 static inline struct vfsmount *
540 ecryptfs_dentry_to_lower_mnt(struct dentry *dentry)
541 {
542 	return ((struct ecryptfs_dentry_info *)dentry->d_fsdata)->lower_path.mnt;
543 }
544 
545 static inline void
546 ecryptfs_set_dentry_lower_mnt(struct dentry *dentry, struct vfsmount *lower_mnt)
547 {
548 	((struct ecryptfs_dentry_info *)dentry->d_fsdata)->lower_path.mnt =
549 		lower_mnt;
550 }
551 
552 #define ecryptfs_printk(type, fmt, arg...) \
553         __ecryptfs_printk(type "%s: " fmt, __func__, ## arg);
554 void __ecryptfs_printk(const char *fmt, ...);
555 
556 extern const struct file_operations ecryptfs_main_fops;
557 extern const struct file_operations ecryptfs_dir_fops;
558 extern const struct inode_operations ecryptfs_main_iops;
559 extern const struct inode_operations ecryptfs_dir_iops;
560 extern const struct inode_operations ecryptfs_symlink_iops;
561 extern const struct super_operations ecryptfs_sops;
562 extern struct dentry_operations ecryptfs_dops;
563 extern struct address_space_operations ecryptfs_aops;
564 extern int ecryptfs_verbosity;
565 extern unsigned int ecryptfs_message_buf_len;
566 extern signed long ecryptfs_message_wait_timeout;
567 extern unsigned int ecryptfs_number_of_users;
568 
569 extern struct kmem_cache *ecryptfs_auth_tok_list_item_cache;
570 extern struct kmem_cache *ecryptfs_file_info_cache;
571 extern struct kmem_cache *ecryptfs_dentry_info_cache;
572 extern struct kmem_cache *ecryptfs_inode_info_cache;
573 extern struct kmem_cache *ecryptfs_sb_info_cache;
574 extern struct kmem_cache *ecryptfs_header_cache_1;
575 extern struct kmem_cache *ecryptfs_header_cache_2;
576 extern struct kmem_cache *ecryptfs_xattr_cache;
577 extern struct kmem_cache *ecryptfs_key_record_cache;
578 extern struct kmem_cache *ecryptfs_key_sig_cache;
579 extern struct kmem_cache *ecryptfs_global_auth_tok_cache;
580 extern struct kmem_cache *ecryptfs_key_tfm_cache;
581 extern struct kmem_cache *ecryptfs_open_req_cache;
582 
583 struct ecryptfs_open_req {
584 #define ECRYPTFS_REQ_PROCESSED 0x00000001
585 #define ECRYPTFS_REQ_DROPPED   0x00000002
586 #define ECRYPTFS_REQ_ZOMBIE    0x00000004
587 	u32 flags;
588 	struct file **lower_file;
589 	struct dentry *lower_dentry;
590 	struct vfsmount *lower_mnt;
591 	wait_queue_head_t wait;
592 	struct mutex mux;
593 	struct list_head kthread_ctl_list;
594 };
595 
596 #define ECRYPTFS_INTERPOSE_FLAG_D_ADD                 0x00000001
597 int ecryptfs_interpose(struct dentry *hidden_dentry,
598 		       struct dentry *this_dentry, struct super_block *sb,
599 		       u32 flags);
600 int ecryptfs_fill_zeros(struct file *file, loff_t new_length);
601 int ecryptfs_decode_filename(struct ecryptfs_crypt_stat *crypt_stat,
602 			     const char *name, int length,
603 			     char **decrypted_name);
604 int ecryptfs_encode_filename(struct ecryptfs_crypt_stat *crypt_stat,
605 			     const char *name, int length,
606 			     char **encoded_name);
607 struct dentry *ecryptfs_lower_dentry(struct dentry *this_dentry);
608 void ecryptfs_dump_hex(char *data, int bytes);
609 int virt_to_scatterlist(const void *addr, int size, struct scatterlist *sg,
610 			int sg_size);
611 int ecryptfs_compute_root_iv(struct ecryptfs_crypt_stat *crypt_stat);
612 void ecryptfs_rotate_iv(unsigned char *iv);
613 void ecryptfs_init_crypt_stat(struct ecryptfs_crypt_stat *crypt_stat);
614 void ecryptfs_destroy_crypt_stat(struct ecryptfs_crypt_stat *crypt_stat);
615 void ecryptfs_destroy_mount_crypt_stat(
616 	struct ecryptfs_mount_crypt_stat *mount_crypt_stat);
617 int ecryptfs_init_crypt_ctx(struct ecryptfs_crypt_stat *crypt_stat);
618 int ecryptfs_write_inode_size_to_metadata(struct inode *ecryptfs_inode);
619 int ecryptfs_encrypt_page(struct page *page);
620 int ecryptfs_decrypt_page(struct page *page);
621 int ecryptfs_write_metadata(struct dentry *ecryptfs_dentry);
622 int ecryptfs_read_metadata(struct dentry *ecryptfs_dentry);
623 int ecryptfs_new_file_context(struct dentry *ecryptfs_dentry);
624 int ecryptfs_read_and_validate_header_region(char *data,
625 					     struct inode *ecryptfs_inode);
626 int ecryptfs_read_and_validate_xattr_region(char *page_virt,
627 					    struct dentry *ecryptfs_dentry);
628 u8 ecryptfs_code_for_cipher_string(char *cipher_name, size_t key_bytes);
629 int ecryptfs_cipher_code_to_string(char *str, u8 cipher_code);
630 void ecryptfs_set_default_sizes(struct ecryptfs_crypt_stat *crypt_stat);
631 int ecryptfs_generate_key_packet_set(char *dest_base,
632 				     struct ecryptfs_crypt_stat *crypt_stat,
633 				     struct dentry *ecryptfs_dentry,
634 				     size_t *len, size_t max);
635 int
636 ecryptfs_parse_packet_set(struct ecryptfs_crypt_stat *crypt_stat,
637 			  unsigned char *src, struct dentry *ecryptfs_dentry);
638 int ecryptfs_truncate(struct dentry *dentry, loff_t new_length);
639 int ecryptfs_inode_test(struct inode *inode, void *candidate_lower_inode);
640 int ecryptfs_inode_set(struct inode *inode, void *lower_inode);
641 void ecryptfs_init_inode(struct inode *inode, struct inode *lower_inode);
642 ssize_t
643 ecryptfs_getxattr_lower(struct dentry *lower_dentry, const char *name,
644 			void *value, size_t size);
645 int
646 ecryptfs_setxattr(struct dentry *dentry, const char *name, const void *value,
647 		  size_t size, int flags);
648 int ecryptfs_read_xattr_region(char *page_virt, struct inode *ecryptfs_inode);
649 int ecryptfs_process_helo(uid_t euid, struct user_namespace *user_ns,
650 			  struct pid *pid);
651 int ecryptfs_process_quit(uid_t euid, struct user_namespace *user_ns,
652 			  struct pid *pid);
653 int ecryptfs_process_response(struct ecryptfs_message *msg, uid_t euid,
654 			      struct user_namespace *user_ns, struct pid *pid,
655 			      u32 seq);
656 int ecryptfs_send_message(char *data, int data_len,
657 			  struct ecryptfs_msg_ctx **msg_ctx);
658 int ecryptfs_wait_for_response(struct ecryptfs_msg_ctx *msg_ctx,
659 			       struct ecryptfs_message **emsg);
660 int ecryptfs_init_messaging(void);
661 void ecryptfs_release_messaging(void);
662 
663 void
664 ecryptfs_write_header_metadata(char *virt,
665 			       struct ecryptfs_crypt_stat *crypt_stat,
666 			       size_t *written);
667 int ecryptfs_add_keysig(struct ecryptfs_crypt_stat *crypt_stat, char *sig);
668 int
669 ecryptfs_add_global_auth_tok(struct ecryptfs_mount_crypt_stat *mount_crypt_stat,
670 			   char *sig);
671 int ecryptfs_get_global_auth_tok_for_sig(
672 	struct ecryptfs_global_auth_tok **global_auth_tok,
673 	struct ecryptfs_mount_crypt_stat *mount_crypt_stat, char *sig);
674 int
675 ecryptfs_add_new_key_tfm(struct ecryptfs_key_tfm **key_tfm, char *cipher_name,
676 			 size_t key_size);
677 int ecryptfs_init_crypto(void);
678 int ecryptfs_destroy_crypto(void);
679 int ecryptfs_tfm_exists(char *cipher_name, struct ecryptfs_key_tfm **key_tfm);
680 int ecryptfs_get_tfm_and_mutex_for_cipher_name(struct crypto_blkcipher **tfm,
681 					       struct mutex **tfm_mutex,
682 					       char *cipher_name);
683 int ecryptfs_keyring_auth_tok_for_sig(struct key **auth_tok_key,
684 				      struct ecryptfs_auth_tok **auth_tok,
685 				      char *sig);
686 int ecryptfs_write_lower(struct inode *ecryptfs_inode, char *data,
687 			 loff_t offset, size_t size);
688 int ecryptfs_write_lower_page_segment(struct inode *ecryptfs_inode,
689 				      struct page *page_for_lower,
690 				      size_t offset_in_page, size_t size);
691 int ecryptfs_write(struct file *ecryptfs_file, char *data, loff_t offset,
692 		   size_t size);
693 int ecryptfs_read_lower(char *data, loff_t offset, size_t size,
694 			struct inode *ecryptfs_inode);
695 int ecryptfs_read_lower_page_segment(struct page *page_for_ecryptfs,
696 				     pgoff_t page_index,
697 				     size_t offset_in_page, size_t size,
698 				     struct inode *ecryptfs_inode);
699 struct page *ecryptfs_get_locked_page(struct file *file, loff_t index);
700 int ecryptfs_exorcise_daemon(struct ecryptfs_daemon *daemon);
701 int ecryptfs_find_daemon_by_euid(struct ecryptfs_daemon **daemon, uid_t euid,
702 				 struct user_namespace *user_ns);
703 int ecryptfs_parse_packet_length(unsigned char *data, size_t *size,
704 				 size_t *length_size);
705 int ecryptfs_write_packet_length(char *dest, size_t size,
706 				 size_t *packet_size_length);
707 int ecryptfs_init_ecryptfs_miscdev(void);
708 void ecryptfs_destroy_ecryptfs_miscdev(void);
709 int ecryptfs_send_miscdev(char *data, size_t data_size,
710 			  struct ecryptfs_msg_ctx *msg_ctx, u8 msg_type,
711 			  u16 msg_flags, struct ecryptfs_daemon *daemon);
712 void ecryptfs_msg_ctx_alloc_to_free(struct ecryptfs_msg_ctx *msg_ctx);
713 int
714 ecryptfs_spawn_daemon(struct ecryptfs_daemon **daemon, uid_t euid,
715 		      struct user_namespace *user_ns, struct pid *pid);
716 int ecryptfs_init_kthread(void);
717 void ecryptfs_destroy_kthread(void);
718 int ecryptfs_privileged_open(struct file **lower_file,
719 			     struct dentry *lower_dentry,
720 			     struct vfsmount *lower_mnt,
721 			     const struct cred *cred);
722 int ecryptfs_init_persistent_file(struct dentry *ecryptfs_dentry);
723 int
724 ecryptfs_write_tag_70_packet(char *dest, size_t *remaining_bytes,
725 			     size_t *packet_size,
726 			     struct ecryptfs_mount_crypt_stat *mount_crypt_stat,
727 			     char *filename, size_t filename_size);
728 int
729 ecryptfs_parse_tag_70_packet(char **filename, size_t *filename_size,
730 			     size_t *packet_size,
731 			     struct ecryptfs_mount_crypt_stat *mount_crypt_stat,
732 			     char *data, size_t max_packet_size);
733 
734 #endif /* #ifndef ECRYPTFS_KERNEL_H */
735