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 #include <linux/backing-dev.h>
39 
40 /* Version verification for shared data structures w/ userspace */
41 #define ECRYPTFS_VERSION_MAJOR 0x00
42 #define ECRYPTFS_VERSION_MINOR 0x04
43 #define ECRYPTFS_SUPPORTED_FILE_VERSION 0x03
44 /* These flags indicate which features are supported by the kernel
45  * module; userspace tools such as the mount helper read
46  * ECRYPTFS_VERSIONING_MASK from a sysfs handle in order to determine
47  * how to behave. */
48 #define ECRYPTFS_VERSIONING_PASSPHRASE            0x00000001
49 #define ECRYPTFS_VERSIONING_PUBKEY                0x00000002
50 #define ECRYPTFS_VERSIONING_PLAINTEXT_PASSTHROUGH 0x00000004
51 #define ECRYPTFS_VERSIONING_POLICY                0x00000008
52 #define ECRYPTFS_VERSIONING_XATTR                 0x00000010
53 #define ECRYPTFS_VERSIONING_MULTKEY               0x00000020
54 #define ECRYPTFS_VERSIONING_DEVMISC               0x00000040
55 #define ECRYPTFS_VERSIONING_HMAC                  0x00000080
56 #define ECRYPTFS_VERSIONING_FILENAME_ENCRYPTION   0x00000100
57 #define ECRYPTFS_VERSIONING_GCM                   0x00000200
58 #define ECRYPTFS_VERSIONING_MASK (ECRYPTFS_VERSIONING_PASSPHRASE \
59 				  | ECRYPTFS_VERSIONING_PLAINTEXT_PASSTHROUGH \
60 				  | ECRYPTFS_VERSIONING_PUBKEY \
61 				  | ECRYPTFS_VERSIONING_XATTR \
62 				  | ECRYPTFS_VERSIONING_MULTKEY \
63 				  | ECRYPTFS_VERSIONING_DEVMISC \
64 				  | ECRYPTFS_VERSIONING_FILENAME_ENCRYPTION)
65 #define ECRYPTFS_MAX_PASSWORD_LENGTH 64
66 #define ECRYPTFS_MAX_PASSPHRASE_BYTES ECRYPTFS_MAX_PASSWORD_LENGTH
67 #define ECRYPTFS_SALT_SIZE 8
68 #define ECRYPTFS_SALT_SIZE_HEX (ECRYPTFS_SALT_SIZE*2)
69 /* The original signature size is only for what is stored on disk; all
70  * in-memory representations are expanded hex, so it better adapted to
71  * be passed around or referenced on the command line */
72 #define ECRYPTFS_SIG_SIZE 8
73 #define ECRYPTFS_SIG_SIZE_HEX (ECRYPTFS_SIG_SIZE*2)
74 #define ECRYPTFS_PASSWORD_SIG_SIZE ECRYPTFS_SIG_SIZE_HEX
75 #define ECRYPTFS_MAX_KEY_BYTES 64
76 #define ECRYPTFS_MAX_ENCRYPTED_KEY_BYTES 512
77 #define ECRYPTFS_DEFAULT_IV_BYTES 16
78 #define ECRYPTFS_FILE_VERSION 0x03
79 #define ECRYPTFS_DEFAULT_EXTENT_SIZE 4096
80 #define ECRYPTFS_MINIMUM_HEADER_EXTENT_SIZE 8192
81 #define ECRYPTFS_DEFAULT_MSG_CTX_ELEMS 32
82 #define ECRYPTFS_DEFAULT_SEND_TIMEOUT HZ
83 #define ECRYPTFS_MAX_MSG_CTX_TTL (HZ*3)
84 #define ECRYPTFS_MAX_PKI_NAME_BYTES 16
85 #define ECRYPTFS_DEFAULT_NUM_USERS 4
86 #define ECRYPTFS_MAX_NUM_USERS 32768
87 #define ECRYPTFS_XATTR_NAME "user.ecryptfs"
88 
89 #define RFC2440_CIPHER_DES3_EDE 0x02
90 #define RFC2440_CIPHER_CAST_5 0x03
91 #define RFC2440_CIPHER_BLOWFISH 0x04
92 #define RFC2440_CIPHER_AES_128 0x07
93 #define RFC2440_CIPHER_AES_192 0x08
94 #define RFC2440_CIPHER_AES_256 0x09
95 #define RFC2440_CIPHER_TWOFISH 0x0a
96 #define RFC2440_CIPHER_CAST_6 0x0b
97 
98 #define RFC2440_CIPHER_RSA 0x01
99 
100 /**
101  * For convenience, we may need to pass around the encrypted session
102  * key between kernel and userspace because the authentication token
103  * may not be extractable.  For example, the TPM may not release the
104  * private key, instead requiring the encrypted data and returning the
105  * decrypted data.
106  */
107 struct ecryptfs_session_key {
108 #define ECRYPTFS_USERSPACE_SHOULD_TRY_TO_DECRYPT 0x00000001
109 #define ECRYPTFS_USERSPACE_SHOULD_TRY_TO_ENCRYPT 0x00000002
110 #define ECRYPTFS_CONTAINS_DECRYPTED_KEY 0x00000004
111 #define ECRYPTFS_CONTAINS_ENCRYPTED_KEY 0x00000008
112 	u32 flags;
113 	u32 encrypted_key_size;
114 	u32 decrypted_key_size;
115 	u8 encrypted_key[ECRYPTFS_MAX_ENCRYPTED_KEY_BYTES];
116 	u8 decrypted_key[ECRYPTFS_MAX_KEY_BYTES];
117 };
118 
119 struct ecryptfs_password {
120 	u32 password_bytes;
121 	s32 hash_algo;
122 	u32 hash_iterations;
123 	u32 session_key_encryption_key_bytes;
124 #define ECRYPTFS_PERSISTENT_PASSWORD 0x01
125 #define ECRYPTFS_SESSION_KEY_ENCRYPTION_KEY_SET 0x02
126 	u32 flags;
127 	/* Iterated-hash concatenation of salt and passphrase */
128 	u8 session_key_encryption_key[ECRYPTFS_MAX_KEY_BYTES];
129 	u8 signature[ECRYPTFS_PASSWORD_SIG_SIZE + 1];
130 	/* Always in expanded hex */
131 	u8 salt[ECRYPTFS_SALT_SIZE];
132 };
133 
134 enum ecryptfs_token_types {ECRYPTFS_PASSWORD, ECRYPTFS_PRIVATE_KEY};
135 
136 struct ecryptfs_private_key {
137 	u32 key_size;
138 	u32 data_len;
139 	u8 signature[ECRYPTFS_PASSWORD_SIG_SIZE + 1];
140 	char pki_type[ECRYPTFS_MAX_PKI_NAME_BYTES + 1];
141 	u8 data[];
142 };
143 
144 /* May be a password or a private key */
145 struct ecryptfs_auth_tok {
146 	u16 version; /* 8-bit major and 8-bit minor */
147 	u16 token_type;
148 #define ECRYPTFS_ENCRYPT_ONLY 0x00000001
149 	u32 flags;
150 	struct ecryptfs_session_key session_key;
151 	u8 reserved[32];
152 	union {
153 		struct ecryptfs_password password;
154 		struct ecryptfs_private_key private_key;
155 	} token;
156 } __attribute__ ((packed));
157 
158 void ecryptfs_dump_auth_tok(struct ecryptfs_auth_tok *auth_tok);
159 extern void ecryptfs_to_hex(char *dst, char *src, size_t src_size);
160 extern void ecryptfs_from_hex(char *dst, char *src, int dst_size);
161 
162 struct ecryptfs_key_record {
163 	unsigned char type;
164 	size_t enc_key_size;
165 	unsigned char sig[ECRYPTFS_SIG_SIZE];
166 	unsigned char enc_key[ECRYPTFS_MAX_ENCRYPTED_KEY_BYTES];
167 };
168 
169 struct ecryptfs_auth_tok_list {
170 	struct ecryptfs_auth_tok *auth_tok;
171 	struct list_head list;
172 };
173 
174 struct ecryptfs_crypt_stat;
175 struct ecryptfs_mount_crypt_stat;
176 
177 struct ecryptfs_page_crypt_context {
178 	struct page *page;
179 #define ECRYPTFS_PREPARE_COMMIT_MODE 0
180 #define ECRYPTFS_WRITEPAGE_MODE      1
181 	unsigned int mode;
182 	union {
183 		struct file *lower_file;
184 		struct writeback_control *wbc;
185 	} param;
186 };
187 
188 static inline struct ecryptfs_auth_tok *
ecryptfs_get_key_payload_data(struct key * key)189 ecryptfs_get_key_payload_data(struct key *key)
190 {
191 	return (struct ecryptfs_auth_tok *)
192 		(((struct user_key_payload*)key->payload.data)->data);
193 }
194 
195 #define ECRYPTFS_MAX_KEYSET_SIZE 1024
196 #define ECRYPTFS_MAX_CIPHER_NAME_SIZE 32
197 #define ECRYPTFS_MAX_NUM_ENC_KEYS 64
198 #define ECRYPTFS_MAX_IV_BYTES 16	/* 128 bits */
199 #define ECRYPTFS_SALT_BYTES 2
200 #define MAGIC_ECRYPTFS_MARKER 0x3c81b7f5
201 #define MAGIC_ECRYPTFS_MARKER_SIZE_BYTES 8	/* 4*2 */
202 #define ECRYPTFS_FILE_SIZE_BYTES (sizeof(u64))
203 #define ECRYPTFS_DEFAULT_CIPHER "aes"
204 #define ECRYPTFS_DEFAULT_KEY_BYTES 16
205 #define ECRYPTFS_DEFAULT_HASH "md5"
206 #define ECRYPTFS_TAG_70_DIGEST ECRYPTFS_DEFAULT_HASH
207 #define ECRYPTFS_TAG_1_PACKET_TYPE 0x01
208 #define ECRYPTFS_TAG_3_PACKET_TYPE 0x8C
209 #define ECRYPTFS_TAG_11_PACKET_TYPE 0xED
210 #define ECRYPTFS_TAG_64_PACKET_TYPE 0x40
211 #define ECRYPTFS_TAG_65_PACKET_TYPE 0x41
212 #define ECRYPTFS_TAG_66_PACKET_TYPE 0x42
213 #define ECRYPTFS_TAG_67_PACKET_TYPE 0x43
214 #define ECRYPTFS_TAG_70_PACKET_TYPE 0x46 /* FNEK-encrypted filename
215 					  * as dentry name */
216 #define ECRYPTFS_TAG_71_PACKET_TYPE 0x47 /* FNEK-encrypted filename in
217 					  * metadata */
218 #define ECRYPTFS_TAG_72_PACKET_TYPE 0x48 /* FEK-encrypted filename as
219 					  * dentry name */
220 #define ECRYPTFS_TAG_73_PACKET_TYPE 0x49 /* FEK-encrypted filename as
221 					  * metadata */
222 /* Constraint: ECRYPTFS_FILENAME_MIN_RANDOM_PREPEND_BYTES >=
223  * ECRYPTFS_MAX_IV_BYTES */
224 #define ECRYPTFS_FILENAME_MIN_RANDOM_PREPEND_BYTES 16
225 #define ECRYPTFS_NON_NULL 0x42 /* A reasonable substitute for NULL */
226 #define MD5_DIGEST_SIZE 16
227 #define ECRYPTFS_TAG_70_DIGEST_SIZE MD5_DIGEST_SIZE
228 #define ECRYPTFS_FEK_ENCRYPTED_FILENAME_PREFIX "ECRYPTFS_FEK_ENCRYPTED."
229 #define ECRYPTFS_FEK_ENCRYPTED_FILENAME_PREFIX_SIZE 23
230 #define ECRYPTFS_FNEK_ENCRYPTED_FILENAME_PREFIX "ECRYPTFS_FNEK_ENCRYPTED."
231 #define ECRYPTFS_FNEK_ENCRYPTED_FILENAME_PREFIX_SIZE 24
232 #define ECRYPTFS_ENCRYPTED_DENTRY_NAME_LEN (18 + 1 + 4 + 1 + 32)
233 
234 struct ecryptfs_key_sig {
235 	struct list_head crypt_stat_list;
236 	char keysig[ECRYPTFS_SIG_SIZE_HEX + 1];
237 };
238 
239 struct ecryptfs_filename {
240 	struct list_head crypt_stat_list;
241 #define ECRYPTFS_FILENAME_CONTAINS_DECRYPTED 0x00000001
242 	u32 flags;
243 	u32 seq_no;
244 	char *filename;
245 	char *encrypted_filename;
246 	size_t filename_size;
247 	size_t encrypted_filename_size;
248 	char fnek_sig[ECRYPTFS_SIG_SIZE_HEX];
249 	char dentry_name[ECRYPTFS_ENCRYPTED_DENTRY_NAME_LEN + 1];
250 };
251 
252 /**
253  * This is the primary struct associated with each encrypted file.
254  *
255  * TODO: cache align/pack?
256  */
257 struct ecryptfs_crypt_stat {
258 #define ECRYPTFS_STRUCT_INITIALIZED   0x00000001
259 #define ECRYPTFS_POLICY_APPLIED       0x00000002
260 #define ECRYPTFS_ENCRYPTED            0x00000004
261 #define ECRYPTFS_SECURITY_WARNING     0x00000008
262 #define ECRYPTFS_ENABLE_HMAC          0x00000010
263 #define ECRYPTFS_ENCRYPT_IV_PAGES     0x00000020
264 #define ECRYPTFS_KEY_VALID            0x00000040
265 #define ECRYPTFS_METADATA_IN_XATTR    0x00000080
266 #define ECRYPTFS_VIEW_AS_ENCRYPTED    0x00000100
267 #define ECRYPTFS_KEY_SET              0x00000200
268 #define ECRYPTFS_ENCRYPT_FILENAMES    0x00000400
269 #define ECRYPTFS_ENCFN_USE_MOUNT_FNEK 0x00000800
270 #define ECRYPTFS_ENCFN_USE_FEK        0x00001000
271 #define ECRYPTFS_UNLINK_SIGS          0x00002000
272 #define ECRYPTFS_I_SIZE_INITIALIZED   0x00004000
273 	u32 flags;
274 	unsigned int file_version;
275 	size_t iv_bytes;
276 	size_t metadata_size;
277 	size_t extent_size; /* Data extent size; default is 4096 */
278 	size_t key_size;
279 	size_t extent_shift;
280 	unsigned int extent_mask;
281 	struct ecryptfs_mount_crypt_stat *mount_crypt_stat;
282 	struct crypto_blkcipher *tfm;
283 	struct crypto_hash *hash_tfm; /* Crypto context for generating
284 				       * the initialization vectors */
285 	unsigned char cipher[ECRYPTFS_MAX_CIPHER_NAME_SIZE];
286 	unsigned char key[ECRYPTFS_MAX_KEY_BYTES];
287 	unsigned char root_iv[ECRYPTFS_MAX_IV_BYTES];
288 	struct list_head keysig_list;
289 	struct mutex keysig_list_mutex;
290 	struct mutex cs_tfm_mutex;
291 	struct mutex cs_hash_tfm_mutex;
292 	struct mutex cs_mutex;
293 };
294 
295 /* inode private data. */
296 struct ecryptfs_inode_info {
297 	struct inode vfs_inode;
298 	struct inode *wii_inode;
299 	struct mutex lower_file_mutex;
300 	atomic_t lower_file_count;
301 	struct file *lower_file;
302 	struct ecryptfs_crypt_stat crypt_stat;
303 };
304 
305 /* dentry private data. Each dentry must keep track of a lower
306  * vfsmount too. */
307 struct ecryptfs_dentry_info {
308 	struct path lower_path;
309 	struct ecryptfs_crypt_stat *crypt_stat;
310 };
311 
312 /**
313  * ecryptfs_global_auth_tok - A key used to encrypt all new files under the mountpoint
314  * @flags: Status flags
315  * @mount_crypt_stat_list: These auth_toks hang off the mount-wide
316  *                         cryptographic context. Every time a new
317  *                         inode comes into existence, eCryptfs copies
318  *                         the auth_toks on that list to the set of
319  *                         auth_toks on the inode's crypt_stat
320  * @global_auth_tok_key: The key from the user's keyring for the sig
321  * @global_auth_tok: The key contents
322  * @sig: The key identifier
323  *
324  * ecryptfs_global_auth_tok structs refer to authentication token keys
325  * in the user keyring that apply to newly created files. A list of
326  * these objects hangs off of the mount_crypt_stat struct for any
327  * given eCryptfs mount. This struct maintains a reference to both the
328  * key contents and the key itself so that the key can be put on
329  * unmount.
330  */
331 struct ecryptfs_global_auth_tok {
332 #define ECRYPTFS_AUTH_TOK_INVALID 0x00000001
333 #define ECRYPTFS_AUTH_TOK_FNEK    0x00000002
334 	u32 flags;
335 	struct list_head mount_crypt_stat_list;
336 	struct key *global_auth_tok_key;
337 	unsigned char sig[ECRYPTFS_SIG_SIZE_HEX + 1];
338 };
339 
340 /**
341  * ecryptfs_key_tfm - Persistent key tfm
342  * @key_tfm: crypto API handle to the key
343  * @key_size: Key size in bytes
344  * @key_tfm_mutex: Mutex to ensure only one operation in eCryptfs is
345  *                 using the persistent TFM at any point in time
346  * @key_tfm_list: Handle to hang this off the module-wide TFM list
347  * @cipher_name: String name for the cipher for this TFM
348  *
349  * Typically, eCryptfs will use the same ciphers repeatedly throughout
350  * the course of its operations. In order to avoid unnecessarily
351  * destroying and initializing the same cipher repeatedly, eCryptfs
352  * keeps a list of crypto API contexts around to use when needed.
353  */
354 struct ecryptfs_key_tfm {
355 	struct crypto_blkcipher *key_tfm;
356 	size_t key_size;
357 	struct mutex key_tfm_mutex;
358 	struct list_head key_tfm_list;
359 	unsigned char cipher_name[ECRYPTFS_MAX_CIPHER_NAME_SIZE + 1];
360 };
361 
362 extern struct mutex key_tfm_list_mutex;
363 
364 /**
365  * This struct is to enable a mount-wide passphrase/salt combo. This
366  * is more or less a stopgap to provide similar functionality to other
367  * crypto filesystems like EncFS or CFS until full policy support is
368  * implemented in eCryptfs.
369  */
370 struct ecryptfs_mount_crypt_stat {
371 	/* Pointers to memory we do not own, do not free these */
372 #define ECRYPTFS_PLAINTEXT_PASSTHROUGH_ENABLED 0x00000001
373 #define ECRYPTFS_XATTR_METADATA_ENABLED        0x00000002
374 #define ECRYPTFS_ENCRYPTED_VIEW_ENABLED        0x00000004
375 #define ECRYPTFS_MOUNT_CRYPT_STAT_INITIALIZED  0x00000008
376 #define ECRYPTFS_GLOBAL_ENCRYPT_FILENAMES      0x00000010
377 #define ECRYPTFS_GLOBAL_ENCFN_USE_MOUNT_FNEK   0x00000020
378 #define ECRYPTFS_GLOBAL_ENCFN_USE_FEK          0x00000040
379 #define ECRYPTFS_GLOBAL_MOUNT_AUTH_TOK_ONLY    0x00000080
380 	u32 flags;
381 	struct list_head global_auth_tok_list;
382 	struct mutex global_auth_tok_list_mutex;
383 	size_t global_default_cipher_key_size;
384 	size_t global_default_fn_cipher_key_bytes;
385 	unsigned char global_default_cipher_name[ECRYPTFS_MAX_CIPHER_NAME_SIZE
386 						 + 1];
387 	unsigned char global_default_fn_cipher_name[
388 		ECRYPTFS_MAX_CIPHER_NAME_SIZE + 1];
389 	char global_default_fnek_sig[ECRYPTFS_SIG_SIZE_HEX + 1];
390 };
391 
392 /* superblock private data. */
393 struct ecryptfs_sb_info {
394 	struct super_block *wsi_sb;
395 	struct ecryptfs_mount_crypt_stat mount_crypt_stat;
396 	struct backing_dev_info bdi;
397 };
398 
399 /* file private data. */
400 struct ecryptfs_file_info {
401 	struct file *wfi_file;
402 	struct ecryptfs_crypt_stat *crypt_stat;
403 };
404 
405 /* auth_tok <=> encrypted_session_key mappings */
406 struct ecryptfs_auth_tok_list_item {
407 	unsigned char encrypted_session_key[ECRYPTFS_MAX_KEY_BYTES];
408 	struct list_head list;
409 	struct ecryptfs_auth_tok auth_tok;
410 };
411 
412 struct ecryptfs_message {
413 	/* Can never be greater than ecryptfs_message_buf_len */
414 	/* Used to find the parent msg_ctx */
415 	/* Inherits from msg_ctx->index */
416 	u32 index;
417 	u32 data_len;
418 	u8 data[];
419 };
420 
421 struct ecryptfs_msg_ctx {
422 #define ECRYPTFS_MSG_CTX_STATE_FREE     0x01
423 #define ECRYPTFS_MSG_CTX_STATE_PENDING  0x02
424 #define ECRYPTFS_MSG_CTX_STATE_DONE     0x03
425 #define ECRYPTFS_MSG_CTX_STATE_NO_REPLY 0x04
426 	u8 state;
427 #define ECRYPTFS_MSG_HELO 100
428 #define ECRYPTFS_MSG_QUIT 101
429 #define ECRYPTFS_MSG_REQUEST 102
430 #define ECRYPTFS_MSG_RESPONSE 103
431 	u8 type;
432 	u32 index;
433 	/* Counter converts to a sequence number. Each message sent
434 	 * out for which we expect a response has an associated
435 	 * sequence number. The response must have the same sequence
436 	 * number as the counter for the msg_stc for the message to be
437 	 * valid. */
438 	u32 counter;
439 	size_t msg_size;
440 	struct ecryptfs_message *msg;
441 	struct task_struct *task;
442 	struct list_head node;
443 	struct list_head daemon_out_list;
444 	struct mutex mux;
445 };
446 
447 struct ecryptfs_daemon;
448 
449 struct ecryptfs_daemon {
450 #define ECRYPTFS_DAEMON_IN_READ      0x00000001
451 #define ECRYPTFS_DAEMON_IN_POLL      0x00000002
452 #define ECRYPTFS_DAEMON_ZOMBIE       0x00000004
453 #define ECRYPTFS_DAEMON_MISCDEV_OPEN 0x00000008
454 	u32 flags;
455 	u32 num_queued_msg_ctx;
456 	struct pid *pid;
457 	uid_t euid;
458 	struct user_namespace *user_ns;
459 	struct task_struct *task;
460 	struct mutex mux;
461 	struct list_head msg_ctx_out_queue;
462 	wait_queue_head_t wait;
463 	struct hlist_node euid_chain;
464 };
465 
466 extern struct mutex ecryptfs_daemon_hash_mux;
467 
468 static inline size_t
ecryptfs_lower_header_size(struct ecryptfs_crypt_stat * crypt_stat)469 ecryptfs_lower_header_size(struct ecryptfs_crypt_stat *crypt_stat)
470 {
471 	if (crypt_stat->flags & ECRYPTFS_METADATA_IN_XATTR)
472 		return 0;
473 	return crypt_stat->metadata_size;
474 }
475 
476 static inline struct ecryptfs_file_info *
ecryptfs_file_to_private(struct file * file)477 ecryptfs_file_to_private(struct file *file)
478 {
479 	return file->private_data;
480 }
481 
482 static inline void
ecryptfs_set_file_private(struct file * file,struct ecryptfs_file_info * file_info)483 ecryptfs_set_file_private(struct file *file,
484 			  struct ecryptfs_file_info *file_info)
485 {
486 	file->private_data = file_info;
487 }
488 
ecryptfs_file_to_lower(struct file * file)489 static inline struct file *ecryptfs_file_to_lower(struct file *file)
490 {
491 	return ((struct ecryptfs_file_info *)file->private_data)->wfi_file;
492 }
493 
494 static inline void
ecryptfs_set_file_lower(struct file * file,struct file * lower_file)495 ecryptfs_set_file_lower(struct file *file, struct file *lower_file)
496 {
497 	((struct ecryptfs_file_info *)file->private_data)->wfi_file =
498 		lower_file;
499 }
500 
501 static inline struct ecryptfs_inode_info *
ecryptfs_inode_to_private(struct inode * inode)502 ecryptfs_inode_to_private(struct inode *inode)
503 {
504 	return container_of(inode, struct ecryptfs_inode_info, vfs_inode);
505 }
506 
ecryptfs_inode_to_lower(struct inode * inode)507 static inline struct inode *ecryptfs_inode_to_lower(struct inode *inode)
508 {
509 	return ecryptfs_inode_to_private(inode)->wii_inode;
510 }
511 
512 static inline void
ecryptfs_set_inode_lower(struct inode * inode,struct inode * lower_inode)513 ecryptfs_set_inode_lower(struct inode *inode, struct inode *lower_inode)
514 {
515 	ecryptfs_inode_to_private(inode)->wii_inode = lower_inode;
516 }
517 
518 static inline struct ecryptfs_sb_info *
ecryptfs_superblock_to_private(struct super_block * sb)519 ecryptfs_superblock_to_private(struct super_block *sb)
520 {
521 	return (struct ecryptfs_sb_info *)sb->s_fs_info;
522 }
523 
524 static inline void
ecryptfs_set_superblock_private(struct super_block * sb,struct ecryptfs_sb_info * sb_info)525 ecryptfs_set_superblock_private(struct super_block *sb,
526 				struct ecryptfs_sb_info *sb_info)
527 {
528 	sb->s_fs_info = sb_info;
529 }
530 
531 static inline struct super_block *
ecryptfs_superblock_to_lower(struct super_block * sb)532 ecryptfs_superblock_to_lower(struct super_block *sb)
533 {
534 	return ((struct ecryptfs_sb_info *)sb->s_fs_info)->wsi_sb;
535 }
536 
537 static inline void
ecryptfs_set_superblock_lower(struct super_block * sb,struct super_block * lower_sb)538 ecryptfs_set_superblock_lower(struct super_block *sb,
539 			      struct super_block *lower_sb)
540 {
541 	((struct ecryptfs_sb_info *)sb->s_fs_info)->wsi_sb = lower_sb;
542 }
543 
544 static inline struct ecryptfs_dentry_info *
ecryptfs_dentry_to_private(struct dentry * dentry)545 ecryptfs_dentry_to_private(struct dentry *dentry)
546 {
547 	return (struct ecryptfs_dentry_info *)dentry->d_fsdata;
548 }
549 
550 static inline void
ecryptfs_set_dentry_private(struct dentry * dentry,struct ecryptfs_dentry_info * dentry_info)551 ecryptfs_set_dentry_private(struct dentry *dentry,
552 			    struct ecryptfs_dentry_info *dentry_info)
553 {
554 	dentry->d_fsdata = dentry_info;
555 }
556 
557 static inline struct dentry *
ecryptfs_dentry_to_lower(struct dentry * dentry)558 ecryptfs_dentry_to_lower(struct dentry *dentry)
559 {
560 	return ((struct ecryptfs_dentry_info *)dentry->d_fsdata)->lower_path.dentry;
561 }
562 
563 static inline void
ecryptfs_set_dentry_lower(struct dentry * dentry,struct dentry * lower_dentry)564 ecryptfs_set_dentry_lower(struct dentry *dentry, struct dentry *lower_dentry)
565 {
566 	((struct ecryptfs_dentry_info *)dentry->d_fsdata)->lower_path.dentry =
567 		lower_dentry;
568 }
569 
570 static inline struct vfsmount *
ecryptfs_dentry_to_lower_mnt(struct dentry * dentry)571 ecryptfs_dentry_to_lower_mnt(struct dentry *dentry)
572 {
573 	return ((struct ecryptfs_dentry_info *)dentry->d_fsdata)->lower_path.mnt;
574 }
575 
576 static inline void
ecryptfs_set_dentry_lower_mnt(struct dentry * dentry,struct vfsmount * lower_mnt)577 ecryptfs_set_dentry_lower_mnt(struct dentry *dentry, struct vfsmount *lower_mnt)
578 {
579 	((struct ecryptfs_dentry_info *)dentry->d_fsdata)->lower_path.mnt =
580 		lower_mnt;
581 }
582 
583 #define ecryptfs_printk(type, fmt, arg...) \
584         __ecryptfs_printk(type "%s: " fmt, __func__, ## arg);
585 __attribute__ ((format(printf, 1, 2)))
586 void __ecryptfs_printk(const char *fmt, ...);
587 
588 extern const struct file_operations ecryptfs_main_fops;
589 extern const struct file_operations ecryptfs_dir_fops;
590 extern const struct inode_operations ecryptfs_main_iops;
591 extern const struct inode_operations ecryptfs_dir_iops;
592 extern const struct inode_operations ecryptfs_symlink_iops;
593 extern const struct super_operations ecryptfs_sops;
594 extern const struct dentry_operations ecryptfs_dops;
595 extern const struct address_space_operations ecryptfs_aops;
596 extern int ecryptfs_verbosity;
597 extern unsigned int ecryptfs_message_buf_len;
598 extern signed long ecryptfs_message_wait_timeout;
599 extern unsigned int ecryptfs_number_of_users;
600 
601 extern struct kmem_cache *ecryptfs_auth_tok_list_item_cache;
602 extern struct kmem_cache *ecryptfs_file_info_cache;
603 extern struct kmem_cache *ecryptfs_dentry_info_cache;
604 extern struct kmem_cache *ecryptfs_inode_info_cache;
605 extern struct kmem_cache *ecryptfs_sb_info_cache;
606 extern struct kmem_cache *ecryptfs_header_cache_1;
607 extern struct kmem_cache *ecryptfs_header_cache_2;
608 extern struct kmem_cache *ecryptfs_xattr_cache;
609 extern struct kmem_cache *ecryptfs_key_record_cache;
610 extern struct kmem_cache *ecryptfs_key_sig_cache;
611 extern struct kmem_cache *ecryptfs_global_auth_tok_cache;
612 extern struct kmem_cache *ecryptfs_key_tfm_cache;
613 extern struct kmem_cache *ecryptfs_open_req_cache;
614 
615 struct ecryptfs_open_req {
616 #define ECRYPTFS_REQ_PROCESSED 0x00000001
617 #define ECRYPTFS_REQ_DROPPED   0x00000002
618 #define ECRYPTFS_REQ_ZOMBIE    0x00000004
619 	u32 flags;
620 	struct file **lower_file;
621 	struct dentry *lower_dentry;
622 	struct vfsmount *lower_mnt;
623 	wait_queue_head_t wait;
624 	struct mutex mux;
625 	struct list_head kthread_ctl_list;
626 };
627 
628 #define ECRYPTFS_INTERPOSE_FLAG_D_ADD                 0x00000001
629 int ecryptfs_interpose(struct dentry *hidden_dentry,
630 		       struct dentry *this_dentry, struct super_block *sb,
631 		       u32 flags);
632 void ecryptfs_i_size_init(const char *page_virt, struct inode *inode);
633 int ecryptfs_lookup_and_interpose_lower(struct dentry *ecryptfs_dentry,
634 					struct dentry *lower_dentry,
635 					struct inode *ecryptfs_dir_inode);
636 int ecryptfs_decode_and_decrypt_filename(char **decrypted_name,
637 					 size_t *decrypted_name_size,
638 					 struct dentry *ecryptfs_dentry,
639 					 const char *name, size_t name_size);
640 int ecryptfs_fill_zeros(struct file *file, loff_t new_length);
641 int ecryptfs_encrypt_and_encode_filename(
642 	char **encoded_name,
643 	size_t *encoded_name_size,
644 	struct ecryptfs_crypt_stat *crypt_stat,
645 	struct ecryptfs_mount_crypt_stat *mount_crypt_stat,
646 	const char *name, size_t name_size);
647 struct dentry *ecryptfs_lower_dentry(struct dentry *this_dentry);
648 void ecryptfs_dump_hex(char *data, int bytes);
649 int virt_to_scatterlist(const void *addr, int size, struct scatterlist *sg,
650 			int sg_size);
651 int ecryptfs_compute_root_iv(struct ecryptfs_crypt_stat *crypt_stat);
652 void ecryptfs_rotate_iv(unsigned char *iv);
653 void ecryptfs_init_crypt_stat(struct ecryptfs_crypt_stat *crypt_stat);
654 void ecryptfs_destroy_crypt_stat(struct ecryptfs_crypt_stat *crypt_stat);
655 void ecryptfs_destroy_mount_crypt_stat(
656 	struct ecryptfs_mount_crypt_stat *mount_crypt_stat);
657 int ecryptfs_init_crypt_ctx(struct ecryptfs_crypt_stat *crypt_stat);
658 int ecryptfs_write_inode_size_to_metadata(struct inode *ecryptfs_inode);
659 int ecryptfs_encrypt_page(struct page *page);
660 int ecryptfs_decrypt_page(struct page *page);
661 int ecryptfs_write_metadata(struct dentry *ecryptfs_dentry);
662 int ecryptfs_read_metadata(struct dentry *ecryptfs_dentry);
663 int ecryptfs_new_file_context(struct dentry *ecryptfs_dentry);
664 void ecryptfs_write_crypt_stat_flags(char *page_virt,
665 				     struct ecryptfs_crypt_stat *crypt_stat,
666 				     size_t *written);
667 int ecryptfs_read_and_validate_header_region(char *data,
668 					     struct inode *ecryptfs_inode);
669 int ecryptfs_read_and_validate_xattr_region(char *page_virt,
670 					    struct dentry *ecryptfs_dentry);
671 u8 ecryptfs_code_for_cipher_string(char *cipher_name, size_t key_bytes);
672 int ecryptfs_cipher_code_to_string(char *str, u8 cipher_code);
673 void ecryptfs_set_default_sizes(struct ecryptfs_crypt_stat *crypt_stat);
674 int ecryptfs_generate_key_packet_set(char *dest_base,
675 				     struct ecryptfs_crypt_stat *crypt_stat,
676 				     struct dentry *ecryptfs_dentry,
677 				     size_t *len, size_t max);
678 int
679 ecryptfs_parse_packet_set(struct ecryptfs_crypt_stat *crypt_stat,
680 			  unsigned char *src, struct dentry *ecryptfs_dentry);
681 int ecryptfs_truncate(struct dentry *dentry, loff_t new_length);
682 int ecryptfs_inode_test(struct inode *inode, void *candidate_lower_inode);
683 int ecryptfs_inode_set(struct inode *inode, void *lower_inode);
684 void ecryptfs_init_inode(struct inode *inode, struct inode *lower_inode);
685 ssize_t
686 ecryptfs_getxattr_lower(struct dentry *lower_dentry, const char *name,
687 			void *value, size_t size);
688 int
689 ecryptfs_setxattr(struct dentry *dentry, const char *name, const void *value,
690 		  size_t size, int flags);
691 int ecryptfs_read_xattr_region(char *page_virt, struct inode *ecryptfs_inode);
692 int ecryptfs_process_helo(uid_t euid, struct user_namespace *user_ns,
693 			  struct pid *pid);
694 int ecryptfs_process_quit(uid_t euid, struct user_namespace *user_ns,
695 			  struct pid *pid);
696 int ecryptfs_process_response(struct ecryptfs_message *msg, uid_t euid,
697 			      struct user_namespace *user_ns, struct pid *pid,
698 			      u32 seq);
699 int ecryptfs_send_message(char *data, int data_len,
700 			  struct ecryptfs_msg_ctx **msg_ctx);
701 int ecryptfs_wait_for_response(struct ecryptfs_msg_ctx *msg_ctx,
702 			       struct ecryptfs_message **emsg);
703 int ecryptfs_init_messaging(void);
704 void ecryptfs_release_messaging(void);
705 
706 void
707 ecryptfs_write_header_metadata(char *virt,
708 			       struct ecryptfs_crypt_stat *crypt_stat,
709 			       size_t *written);
710 int ecryptfs_add_keysig(struct ecryptfs_crypt_stat *crypt_stat, char *sig);
711 int
712 ecryptfs_add_global_auth_tok(struct ecryptfs_mount_crypt_stat *mount_crypt_stat,
713 			   char *sig, u32 global_auth_tok_flags);
714 int ecryptfs_get_global_auth_tok_for_sig(
715 	struct ecryptfs_global_auth_tok **global_auth_tok,
716 	struct ecryptfs_mount_crypt_stat *mount_crypt_stat, char *sig);
717 int
718 ecryptfs_add_new_key_tfm(struct ecryptfs_key_tfm **key_tfm, char *cipher_name,
719 			 size_t key_size);
720 int ecryptfs_init_crypto(void);
721 int ecryptfs_destroy_crypto(void);
722 int ecryptfs_tfm_exists(char *cipher_name, struct ecryptfs_key_tfm **key_tfm);
723 int ecryptfs_get_tfm_and_mutex_for_cipher_name(struct crypto_blkcipher **tfm,
724 					       struct mutex **tfm_mutex,
725 					       char *cipher_name);
726 int ecryptfs_keyring_auth_tok_for_sig(struct key **auth_tok_key,
727 				      struct ecryptfs_auth_tok **auth_tok,
728 				      char *sig);
729 int ecryptfs_write_lower(struct inode *ecryptfs_inode, char *data,
730 			 loff_t offset, size_t size);
731 int ecryptfs_write_lower_page_segment(struct inode *ecryptfs_inode,
732 				      struct page *page_for_lower,
733 				      size_t offset_in_page, size_t size);
734 int ecryptfs_write(struct inode *inode, char *data, loff_t offset, size_t size);
735 int ecryptfs_read_lower(char *data, loff_t offset, size_t size,
736 			struct inode *ecryptfs_inode);
737 int ecryptfs_read_lower_page_segment(struct page *page_for_ecryptfs,
738 				     pgoff_t page_index,
739 				     size_t offset_in_page, size_t size,
740 				     struct inode *ecryptfs_inode);
741 struct page *ecryptfs_get_locked_page(struct inode *inode, loff_t index);
742 int ecryptfs_exorcise_daemon(struct ecryptfs_daemon *daemon);
743 int ecryptfs_find_daemon_by_euid(struct ecryptfs_daemon **daemon, uid_t euid,
744 				 struct user_namespace *user_ns);
745 int ecryptfs_parse_packet_length(unsigned char *data, size_t *size,
746 				 size_t *length_size);
747 int ecryptfs_write_packet_length(char *dest, size_t size,
748 				 size_t *packet_size_length);
749 int ecryptfs_init_ecryptfs_miscdev(void);
750 void ecryptfs_destroy_ecryptfs_miscdev(void);
751 int ecryptfs_send_miscdev(char *data, size_t data_size,
752 			  struct ecryptfs_msg_ctx *msg_ctx, u8 msg_type,
753 			  u16 msg_flags, struct ecryptfs_daemon *daemon);
754 void ecryptfs_msg_ctx_alloc_to_free(struct ecryptfs_msg_ctx *msg_ctx);
755 int
756 ecryptfs_spawn_daemon(struct ecryptfs_daemon **daemon, uid_t euid,
757 		      struct user_namespace *user_ns, struct pid *pid);
758 int ecryptfs_init_kthread(void);
759 void ecryptfs_destroy_kthread(void);
760 int ecryptfs_privileged_open(struct file **lower_file,
761 			     struct dentry *lower_dentry,
762 			     struct vfsmount *lower_mnt,
763 			     const struct cred *cred);
764 int ecryptfs_get_lower_file(struct dentry *ecryptfs_dentry);
765 void ecryptfs_put_lower_file(struct inode *inode);
766 int
767 ecryptfs_write_tag_70_packet(char *dest, size_t *remaining_bytes,
768 			     size_t *packet_size,
769 			     struct ecryptfs_mount_crypt_stat *mount_crypt_stat,
770 			     char *filename, size_t filename_size);
771 int
772 ecryptfs_parse_tag_70_packet(char **filename, size_t *filename_size,
773 			     size_t *packet_size,
774 			     struct ecryptfs_mount_crypt_stat *mount_crypt_stat,
775 			     char *data, size_t max_packet_size);
776 int ecryptfs_derive_iv(char *iv, struct ecryptfs_crypt_stat *crypt_stat,
777 		       loff_t offset);
778 
779 #endif /* #ifndef ECRYPTFS_KERNEL_H */
780