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1/* SPDX-License-Identifier: GPL-2.0-or-later */
2/**
3 * eCryptfs: Linux filesystem encryption layer
4 * Kernel declarations.
5 *
6 * Copyright (C) 1997-2003 Erez Zadok
7 * Copyright (C) 2001-2003 Stony Brook University
8 * Copyright (C) 2004-2008 International Business Machines Corp.
9 * Author(s): Michael A. Halcrow <mahalcro@us.ibm.com>
10 * Trevor S. Highland <trevor.highland@gmail.com>
11 * Tyler Hicks <code@tyhicks.com>
12 */
13
14#ifndef ECRYPTFS_KERNEL_H
15#define ECRYPTFS_KERNEL_H
16
17#include <crypto/skcipher.h>
18#include <keys/user-type.h>
19#include <keys/encrypted-type.h>
20#include <linux/kernel.h>
21#include <linux/fs.h>
22#include <linux/fs_stack.h>
23#include <linux/namei.h>
24#include <linux/scatterlist.h>
25#include <linux/hash.h>
26#include <linux/nsproxy.h>
27#include <linux/backing-dev.h>
28#include <linux/ecryptfs.h>
29
30#define ECRYPTFS_DEFAULT_IV_BYTES 16
31#define ECRYPTFS_DEFAULT_EXTENT_SIZE 4096
32#define ECRYPTFS_MINIMUM_HEADER_EXTENT_SIZE 8192
33#define ECRYPTFS_DEFAULT_MSG_CTX_ELEMS 32
34#define ECRYPTFS_DEFAULT_SEND_TIMEOUT HZ
35#define ECRYPTFS_MAX_MSG_CTX_TTL (HZ*3)
36#define ECRYPTFS_DEFAULT_NUM_USERS 4
37#define ECRYPTFS_MAX_NUM_USERS 32768
38#define ECRYPTFS_XATTR_NAME "user.ecryptfs"
39
40void ecryptfs_dump_auth_tok(struct ecryptfs_auth_tok *auth_tok);
41static inline void
42ecryptfs_to_hex(char *dst, char *src, size_t src_size)
43{
44 char *end = bin2hex(dst, src, src_size);
45 *end = '\0';
46}
47
48extern void ecryptfs_from_hex(char *dst, char *src, int dst_size);
49
50struct ecryptfs_key_record {
51 unsigned char type;
52 size_t enc_key_size;
53 unsigned char sig[ECRYPTFS_SIG_SIZE];
54 unsigned char enc_key[ECRYPTFS_MAX_ENCRYPTED_KEY_BYTES];
55};
56
57struct ecryptfs_auth_tok_list {
58 struct ecryptfs_auth_tok *auth_tok;
59 struct list_head list;
60};
61
62struct ecryptfs_crypt_stat;
63struct ecryptfs_mount_crypt_stat;
64
65struct ecryptfs_page_crypt_context {
66 struct page *page;
67#define ECRYPTFS_PREPARE_COMMIT_MODE 0
68#define ECRYPTFS_WRITEPAGE_MODE 1
69 unsigned int mode;
70 union {
71 struct file *lower_file;
72 struct writeback_control *wbc;
73 } param;
74};
75
76#if defined(CONFIG_ENCRYPTED_KEYS) || defined(CONFIG_ENCRYPTED_KEYS_MODULE)
77static inline struct ecryptfs_auth_tok *
78ecryptfs_get_encrypted_key_payload_data(struct key *key)
79{
80 struct encrypted_key_payload *payload;
81
82 if (key->type != &key_type_encrypted)
83 return NULL;
84
85 payload = key->payload.data[0];
86 if (!payload)
87 return ERR_PTR(-EKEYREVOKED);
88
89 return (struct ecryptfs_auth_tok *)payload->payload_data;
90}
91
92static inline struct key *ecryptfs_get_encrypted_key(char *sig)
93{
94 return request_key(&key_type_encrypted, sig, NULL);
95}
96
97#else
98static inline struct ecryptfs_auth_tok *
99ecryptfs_get_encrypted_key_payload_data(struct key *key)
100{
101 return NULL;
102}
103
104static inline struct key *ecryptfs_get_encrypted_key(char *sig)
105{
106 return ERR_PTR(-ENOKEY);
107}
108
109#endif /* CONFIG_ENCRYPTED_KEYS */
110
111static inline struct ecryptfs_auth_tok *
112ecryptfs_get_key_payload_data(struct key *key)
113{
114 struct ecryptfs_auth_tok *auth_tok;
115 struct user_key_payload *ukp;
116
117 auth_tok = ecryptfs_get_encrypted_key_payload_data(key);
118 if (auth_tok)
119 return auth_tok;
120
121 ukp = user_key_payload_locked(key);
122 if (!ukp)
123 return ERR_PTR(-EKEYREVOKED);
124
125 return (struct ecryptfs_auth_tok *)ukp->data;
126}
127
128#define ECRYPTFS_MAX_KEYSET_SIZE 1024
129#define ECRYPTFS_MAX_CIPHER_NAME_SIZE 31
130#define ECRYPTFS_MAX_NUM_ENC_KEYS 64
131#define ECRYPTFS_MAX_IV_BYTES 16 /* 128 bits */
132#define ECRYPTFS_SALT_BYTES 2
133#define MAGIC_ECRYPTFS_MARKER 0x3c81b7f5
134#define MAGIC_ECRYPTFS_MARKER_SIZE_BYTES 8 /* 4*2 */
135#define ECRYPTFS_FILE_SIZE_BYTES (sizeof(u64))
136#define ECRYPTFS_SIZE_AND_MARKER_BYTES (ECRYPTFS_FILE_SIZE_BYTES \
137 + MAGIC_ECRYPTFS_MARKER_SIZE_BYTES)
138#define ECRYPTFS_DEFAULT_CIPHER "aes"
139#define ECRYPTFS_DEFAULT_KEY_BYTES 16
140#define ECRYPTFS_DEFAULT_HASH "md5"
141#define ECRYPTFS_TAG_70_DIGEST ECRYPTFS_DEFAULT_HASH
142#define ECRYPTFS_TAG_1_PACKET_TYPE 0x01
143#define ECRYPTFS_TAG_3_PACKET_TYPE 0x8C
144#define ECRYPTFS_TAG_11_PACKET_TYPE 0xED
145#define ECRYPTFS_TAG_64_PACKET_TYPE 0x40
146#define ECRYPTFS_TAG_65_PACKET_TYPE 0x41
147#define ECRYPTFS_TAG_66_PACKET_TYPE 0x42
148#define ECRYPTFS_TAG_67_PACKET_TYPE 0x43
149#define ECRYPTFS_TAG_70_PACKET_TYPE 0x46 /* FNEK-encrypted filename
150 * as dentry name */
151#define ECRYPTFS_TAG_71_PACKET_TYPE 0x47 /* FNEK-encrypted filename in
152 * metadata */
153#define ECRYPTFS_TAG_72_PACKET_TYPE 0x48 /* FEK-encrypted filename as
154 * dentry name */
155#define ECRYPTFS_TAG_73_PACKET_TYPE 0x49 /* FEK-encrypted filename as
156 * metadata */
157#define ECRYPTFS_MIN_PKT_LEN_SIZE 1 /* Min size to specify packet length */
158#define ECRYPTFS_MAX_PKT_LEN_SIZE 2 /* Pass at least this many bytes to
159 * ecryptfs_parse_packet_length() and
160 * ecryptfs_write_packet_length()
161 */
162/* Constraint: ECRYPTFS_FILENAME_MIN_RANDOM_PREPEND_BYTES >=
163 * ECRYPTFS_MAX_IV_BYTES */
164#define ECRYPTFS_FILENAME_MIN_RANDOM_PREPEND_BYTES 16
165#define ECRYPTFS_NON_NULL 0x42 /* A reasonable substitute for NULL */
166#define MD5_DIGEST_SIZE 16
167#define ECRYPTFS_TAG_70_DIGEST_SIZE MD5_DIGEST_SIZE
168#define ECRYPTFS_TAG_70_MIN_METADATA_SIZE (1 + ECRYPTFS_MIN_PKT_LEN_SIZE \
169 + ECRYPTFS_SIG_SIZE + 1 + 1)
170#define ECRYPTFS_TAG_70_MAX_METADATA_SIZE (1 + ECRYPTFS_MAX_PKT_LEN_SIZE \
171 + ECRYPTFS_SIG_SIZE + 1 + 1)
172#define ECRYPTFS_FEK_ENCRYPTED_FILENAME_PREFIX "ECRYPTFS_FEK_ENCRYPTED."
173#define ECRYPTFS_FEK_ENCRYPTED_FILENAME_PREFIX_SIZE 23
174#define ECRYPTFS_FNEK_ENCRYPTED_FILENAME_PREFIX "ECRYPTFS_FNEK_ENCRYPTED."
175#define ECRYPTFS_FNEK_ENCRYPTED_FILENAME_PREFIX_SIZE 24
176#define ECRYPTFS_ENCRYPTED_DENTRY_NAME_LEN (18 + 1 + 4 + 1 + 32)
177
178#ifdef CONFIG_ECRYPT_FS_MESSAGING
179# define ECRYPTFS_VERSIONING_MASK_MESSAGING (ECRYPTFS_VERSIONING_DEVMISC \
180 | ECRYPTFS_VERSIONING_PUBKEY)
181#else
182# define ECRYPTFS_VERSIONING_MASK_MESSAGING 0
183#endif
184
185#define ECRYPTFS_VERSIONING_MASK (ECRYPTFS_VERSIONING_PASSPHRASE \
186 | ECRYPTFS_VERSIONING_PLAINTEXT_PASSTHROUGH \
187 | ECRYPTFS_VERSIONING_XATTR \
188 | ECRYPTFS_VERSIONING_MULTKEY \
189 | ECRYPTFS_VERSIONING_MASK_MESSAGING \
190 | ECRYPTFS_VERSIONING_FILENAME_ENCRYPTION)
191struct ecryptfs_key_sig {
192 struct list_head crypt_stat_list;
193 char keysig[ECRYPTFS_SIG_SIZE_HEX + 1];
194};
195
196struct ecryptfs_filename {
197 struct list_head crypt_stat_list;
198#define ECRYPTFS_FILENAME_CONTAINS_DECRYPTED 0x00000001
199 u32 flags;
200 u32 seq_no;
201 char *filename;
202 char *encrypted_filename;
203 size_t filename_size;
204 size_t encrypted_filename_size;
205 char fnek_sig[ECRYPTFS_SIG_SIZE_HEX];
206 char dentry_name[ECRYPTFS_ENCRYPTED_DENTRY_NAME_LEN + 1];
207};
208
209/**
210 * This is the primary struct associated with each encrypted file.
211 *
212 * TODO: cache align/pack?
213 */
214struct ecryptfs_crypt_stat {
215#define ECRYPTFS_STRUCT_INITIALIZED 0x00000001
216#define ECRYPTFS_POLICY_APPLIED 0x00000002
217#define ECRYPTFS_ENCRYPTED 0x00000004
218#define ECRYPTFS_SECURITY_WARNING 0x00000008
219#define ECRYPTFS_ENABLE_HMAC 0x00000010
220#define ECRYPTFS_ENCRYPT_IV_PAGES 0x00000020
221#define ECRYPTFS_KEY_VALID 0x00000040
222#define ECRYPTFS_METADATA_IN_XATTR 0x00000080
223#define ECRYPTFS_VIEW_AS_ENCRYPTED 0x00000100
224#define ECRYPTFS_KEY_SET 0x00000200
225#define ECRYPTFS_ENCRYPT_FILENAMES 0x00000400
226#define ECRYPTFS_ENCFN_USE_MOUNT_FNEK 0x00000800
227#define ECRYPTFS_ENCFN_USE_FEK 0x00001000
228#define ECRYPTFS_UNLINK_SIGS 0x00002000
229#define ECRYPTFS_I_SIZE_INITIALIZED 0x00004000
230 u32 flags;
231 unsigned int file_version;
232 size_t iv_bytes;
233 size_t metadata_size;
234 size_t extent_size; /* Data extent size; default is 4096 */
235 size_t key_size;
236 size_t extent_shift;
237 unsigned int extent_mask;
238 struct ecryptfs_mount_crypt_stat *mount_crypt_stat;
239 struct crypto_skcipher *tfm;
240 struct crypto_shash *hash_tfm; /* Crypto context for generating
241 * the initialization vectors */
242 unsigned char cipher[ECRYPTFS_MAX_CIPHER_NAME_SIZE + 1];
243 unsigned char key[ECRYPTFS_MAX_KEY_BYTES];
244 unsigned char root_iv[ECRYPTFS_MAX_IV_BYTES];
245 struct list_head keysig_list;
246 struct mutex keysig_list_mutex;
247 struct mutex cs_tfm_mutex;
248 struct mutex cs_mutex;
249};
250
251/* inode private data. */
252struct ecryptfs_inode_info {
253 struct inode vfs_inode;
254 struct inode *wii_inode;
255 struct mutex lower_file_mutex;
256 atomic_t lower_file_count;
257 struct file *lower_file;
258 struct ecryptfs_crypt_stat crypt_stat;
259};
260
261/* dentry private data. Each dentry must keep track of a lower
262 * vfsmount too. */
263struct ecryptfs_dentry_info {
264 struct path lower_path;
265 struct rcu_head rcu;
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 */
287struct 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 */
310struct 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
318extern 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 */
326struct 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. */
349struct ecryptfs_sb_info {
350 struct super_block *wsi_sb;
351 struct ecryptfs_mount_crypt_stat mount_crypt_stat;
352};
353
354/* file private data. */
355struct ecryptfs_file_info {
356 struct file *wfi_file;
357 struct ecryptfs_crypt_stat *crypt_stat;
358};
359
360/* auth_tok <=> encrypted_session_key mappings */
361struct ecryptfs_auth_tok_list_item {
362 unsigned char encrypted_session_key[ECRYPTFS_MAX_KEY_BYTES];
363 struct list_head list;
364 struct ecryptfs_auth_tok auth_tok;
365};
366
367struct ecryptfs_message {
368 /* Can never be greater than ecryptfs_message_buf_len */
369 /* Used to find the parent msg_ctx */
370 /* Inherits from msg_ctx->index */
371 u32 index;
372 u32 data_len;
373 u8 data[];
374};
375
376struct ecryptfs_msg_ctx {
377#define ECRYPTFS_MSG_CTX_STATE_FREE 0x01
378#define ECRYPTFS_MSG_CTX_STATE_PENDING 0x02
379#define ECRYPTFS_MSG_CTX_STATE_DONE 0x03
380#define ECRYPTFS_MSG_CTX_STATE_NO_REPLY 0x04
381 u8 state;
382#define ECRYPTFS_MSG_HELO 100
383#define ECRYPTFS_MSG_QUIT 101
384#define ECRYPTFS_MSG_REQUEST 102
385#define ECRYPTFS_MSG_RESPONSE 103
386 u8 type;
387 u32 index;
388 /* Counter converts to a sequence number. Each message sent
389 * out for which we expect a response has an associated
390 * sequence number. The response must have the same sequence
391 * number as the counter for the msg_stc for the message to be
392 * valid. */
393 u32 counter;
394 size_t msg_size;
395 struct ecryptfs_message *msg;
396 struct task_struct *task;
397 struct list_head node;
398 struct list_head daemon_out_list;
399 struct mutex mux;
400};
401
402struct ecryptfs_daemon {
403#define ECRYPTFS_DAEMON_IN_READ 0x00000001
404#define ECRYPTFS_DAEMON_IN_POLL 0x00000002
405#define ECRYPTFS_DAEMON_ZOMBIE 0x00000004
406#define ECRYPTFS_DAEMON_MISCDEV_OPEN 0x00000008
407 u32 flags;
408 u32 num_queued_msg_ctx;
409 struct file *file;
410 struct mutex mux;
411 struct list_head msg_ctx_out_queue;
412 wait_queue_head_t wait;
413 struct hlist_node euid_chain;
414};
415
416#ifdef CONFIG_ECRYPT_FS_MESSAGING
417extern struct mutex ecryptfs_daemon_hash_mux;
418#endif
419
420static inline size_t
421ecryptfs_lower_header_size(struct ecryptfs_crypt_stat *crypt_stat)
422{
423 if (crypt_stat->flags & ECRYPTFS_METADATA_IN_XATTR)
424 return 0;
425 return crypt_stat->metadata_size;
426}
427
428static inline struct ecryptfs_file_info *
429ecryptfs_file_to_private(struct file *file)
430{
431 return file->private_data;
432}
433
434static inline void
435ecryptfs_set_file_private(struct file *file,
436 struct ecryptfs_file_info *file_info)
437{
438 file->private_data = file_info;
439}
440
441static inline struct file *ecryptfs_file_to_lower(struct file *file)
442{
443 return ((struct ecryptfs_file_info *)file->private_data)->wfi_file;
444}
445
446static inline void
447ecryptfs_set_file_lower(struct file *file, struct file *lower_file)
448{
449 ((struct ecryptfs_file_info *)file->private_data)->wfi_file =
450 lower_file;
451}
452
453static inline struct ecryptfs_inode_info *
454ecryptfs_inode_to_private(struct inode *inode)
455{
456 return container_of(inode, struct ecryptfs_inode_info, vfs_inode);
457}
458
459static inline struct inode *ecryptfs_inode_to_lower(struct inode *inode)
460{
461 return ecryptfs_inode_to_private(inode)->wii_inode;
462}
463
464static inline void
465ecryptfs_set_inode_lower(struct inode *inode, struct inode *lower_inode)
466{
467 ecryptfs_inode_to_private(inode)->wii_inode = lower_inode;
468}
469
470static inline struct ecryptfs_sb_info *
471ecryptfs_superblock_to_private(struct super_block *sb)
472{
473 return (struct ecryptfs_sb_info *)sb->s_fs_info;
474}
475
476static inline void
477ecryptfs_set_superblock_private(struct super_block *sb,
478 struct ecryptfs_sb_info *sb_info)
479{
480 sb->s_fs_info = sb_info;
481}
482
483static inline struct super_block *
484ecryptfs_superblock_to_lower(struct super_block *sb)
485{
486 return ((struct ecryptfs_sb_info *)sb->s_fs_info)->wsi_sb;
487}
488
489static inline void
490ecryptfs_set_superblock_lower(struct super_block *sb,
491 struct super_block *lower_sb)
492{
493 ((struct ecryptfs_sb_info *)sb->s_fs_info)->wsi_sb = lower_sb;
494}
495
496static inline void
497ecryptfs_set_dentry_private(struct dentry *dentry,
498 struct ecryptfs_dentry_info *dentry_info)
499{
500 dentry->d_fsdata = dentry_info;
501}
502
503static inline struct dentry *
504ecryptfs_dentry_to_lower(struct dentry *dentry)
505{
506 return ((struct ecryptfs_dentry_info *)dentry->d_fsdata)->lower_path.dentry;
507}
508
509static inline struct path *
510ecryptfs_dentry_to_lower_path(struct dentry *dentry)
511{
512 return &((struct ecryptfs_dentry_info *)dentry->d_fsdata)->lower_path;
513}
514
515#define ecryptfs_printk(type, fmt, arg...) \
516 __ecryptfs_printk(type "%s: " fmt, __func__, ## arg)
517__printf(1, 2)
518void __ecryptfs_printk(const char *fmt, ...);
519
520extern const struct file_operations ecryptfs_main_fops;
521extern const struct file_operations ecryptfs_dir_fops;
522extern const struct inode_operations ecryptfs_main_iops;
523extern const struct inode_operations ecryptfs_dir_iops;
524extern const struct inode_operations ecryptfs_symlink_iops;
525extern const struct super_operations ecryptfs_sops;
526extern const struct dentry_operations ecryptfs_dops;
527extern const struct address_space_operations ecryptfs_aops;
528extern int ecryptfs_verbosity;
529extern unsigned int ecryptfs_message_buf_len;
530extern signed long ecryptfs_message_wait_timeout;
531extern unsigned int ecryptfs_number_of_users;
532
533extern struct kmem_cache *ecryptfs_auth_tok_list_item_cache;
534extern struct kmem_cache *ecryptfs_file_info_cache;
535extern struct kmem_cache *ecryptfs_dentry_info_cache;
536extern struct kmem_cache *ecryptfs_inode_info_cache;
537extern struct kmem_cache *ecryptfs_sb_info_cache;
538extern struct kmem_cache *ecryptfs_header_cache;
539extern struct kmem_cache *ecryptfs_xattr_cache;
540extern struct kmem_cache *ecryptfs_key_record_cache;
541extern struct kmem_cache *ecryptfs_key_sig_cache;
542extern struct kmem_cache *ecryptfs_global_auth_tok_cache;
543extern struct kmem_cache *ecryptfs_key_tfm_cache;
544
545struct inode *ecryptfs_get_inode(struct inode *lower_inode,
546 struct super_block *sb);
547void ecryptfs_i_size_init(const char *page_virt, struct inode *inode);
548int ecryptfs_initialize_file(struct dentry *ecryptfs_dentry,
549 struct inode *ecryptfs_inode);
550int ecryptfs_decode_and_decrypt_filename(char **decrypted_name,
551 size_t *decrypted_name_size,
552 struct super_block *sb,
553 const char *name, size_t name_size);
554int ecryptfs_fill_zeros(struct file *file, loff_t new_length);
555int ecryptfs_encrypt_and_encode_filename(
556 char **encoded_name,
557 size_t *encoded_name_size,
558 struct ecryptfs_mount_crypt_stat *mount_crypt_stat,
559 const char *name, size_t name_size);
560struct dentry *ecryptfs_lower_dentry(struct dentry *this_dentry);
561void ecryptfs_dump_hex(char *data, int bytes);
562int virt_to_scatterlist(const void *addr, int size, struct scatterlist *sg,
563 int sg_size);
564int ecryptfs_compute_root_iv(struct ecryptfs_crypt_stat *crypt_stat);
565void ecryptfs_rotate_iv(unsigned char *iv);
566int ecryptfs_init_crypt_stat(struct ecryptfs_crypt_stat *crypt_stat);
567void ecryptfs_destroy_crypt_stat(struct ecryptfs_crypt_stat *crypt_stat);
568void ecryptfs_destroy_mount_crypt_stat(
569 struct ecryptfs_mount_crypt_stat *mount_crypt_stat);
570int ecryptfs_init_crypt_ctx(struct ecryptfs_crypt_stat *crypt_stat);
571int ecryptfs_write_inode_size_to_metadata(struct inode *ecryptfs_inode);
572int ecryptfs_encrypt_page(struct page *page);
573int ecryptfs_decrypt_page(struct page *page);
574int ecryptfs_write_metadata(struct dentry *ecryptfs_dentry,
575 struct inode *ecryptfs_inode);
576int ecryptfs_read_metadata(struct dentry *ecryptfs_dentry);
577int ecryptfs_new_file_context(struct inode *ecryptfs_inode);
578void ecryptfs_write_crypt_stat_flags(char *page_virt,
579 struct ecryptfs_crypt_stat *crypt_stat,
580 size_t *written);
581int ecryptfs_read_and_validate_header_region(struct inode *inode);
582int ecryptfs_read_and_validate_xattr_region(struct dentry *dentry,
583 struct inode *inode);
584u8 ecryptfs_code_for_cipher_string(char *cipher_name, size_t key_bytes);
585int ecryptfs_cipher_code_to_string(char *str, u8 cipher_code);
586void ecryptfs_set_default_sizes(struct ecryptfs_crypt_stat *crypt_stat);
587int ecryptfs_generate_key_packet_set(char *dest_base,
588 struct ecryptfs_crypt_stat *crypt_stat,
589 struct dentry *ecryptfs_dentry,
590 size_t *len, size_t max);
591int
592ecryptfs_parse_packet_set(struct ecryptfs_crypt_stat *crypt_stat,
593 unsigned char *src, struct dentry *ecryptfs_dentry);
594int ecryptfs_truncate(struct dentry *dentry, loff_t new_length);
595ssize_t
596ecryptfs_getxattr_lower(struct dentry *lower_dentry, struct inode *lower_inode,
597 const char *name, void *value, size_t size);
598int
599ecryptfs_setxattr(struct dentry *dentry, struct inode *inode, const char *name,
600 const void *value, size_t size, int flags);
601int ecryptfs_read_xattr_region(char *page_virt, struct inode *ecryptfs_inode);
602#ifdef CONFIG_ECRYPT_FS_MESSAGING
603int ecryptfs_process_response(struct ecryptfs_daemon *daemon,
604 struct ecryptfs_message *msg, u32 seq);
605int ecryptfs_send_message(char *data, int data_len,
606 struct ecryptfs_msg_ctx **msg_ctx);
607int ecryptfs_wait_for_response(struct ecryptfs_msg_ctx *msg_ctx,
608 struct ecryptfs_message **emsg);
609int ecryptfs_init_messaging(void);
610void ecryptfs_release_messaging(void);
611#else
612static inline int ecryptfs_init_messaging(void)
613{
614 return 0;
615}
616static inline void ecryptfs_release_messaging(void)
617{ }
618static inline int ecryptfs_send_message(char *data, int data_len,
619 struct ecryptfs_msg_ctx **msg_ctx)
620{
621 return -ENOTCONN;
622}
623static inline int ecryptfs_wait_for_response(struct ecryptfs_msg_ctx *msg_ctx,
624 struct ecryptfs_message **emsg)
625{
626 return -ENOMSG;
627}
628#endif
629
630void
631ecryptfs_write_header_metadata(char *virt,
632 struct ecryptfs_crypt_stat *crypt_stat,
633 size_t *written);
634int ecryptfs_add_keysig(struct ecryptfs_crypt_stat *crypt_stat, char *sig);
635int
636ecryptfs_add_global_auth_tok(struct ecryptfs_mount_crypt_stat *mount_crypt_stat,
637 char *sig, u32 global_auth_tok_flags);
638int ecryptfs_get_global_auth_tok_for_sig(
639 struct ecryptfs_global_auth_tok **global_auth_tok,
640 struct ecryptfs_mount_crypt_stat *mount_crypt_stat, char *sig);
641int
642ecryptfs_add_new_key_tfm(struct ecryptfs_key_tfm **key_tfm, char *cipher_name,
643 size_t key_size);
644int ecryptfs_init_crypto(void);
645int ecryptfs_destroy_crypto(void);
646int ecryptfs_tfm_exists(char *cipher_name, struct ecryptfs_key_tfm **key_tfm);
647int ecryptfs_get_tfm_and_mutex_for_cipher_name(struct crypto_skcipher **tfm,
648 struct mutex **tfm_mutex,
649 char *cipher_name);
650int ecryptfs_keyring_auth_tok_for_sig(struct key **auth_tok_key,
651 struct ecryptfs_auth_tok **auth_tok,
652 char *sig);
653int ecryptfs_write_lower(struct inode *ecryptfs_inode, char *data,
654 loff_t offset, size_t size);
655int ecryptfs_write_lower_page_segment(struct inode *ecryptfs_inode,
656 struct page *page_for_lower,
657 size_t offset_in_page, size_t size);
658int ecryptfs_write(struct inode *inode, char *data, loff_t offset, size_t size);
659int ecryptfs_read_lower(char *data, loff_t offset, size_t size,
660 struct inode *ecryptfs_inode);
661int ecryptfs_read_lower_page_segment(struct page *page_for_ecryptfs,
662 pgoff_t page_index,
663 size_t offset_in_page, size_t size,
664 struct inode *ecryptfs_inode);
665struct page *ecryptfs_get_locked_page(struct inode *inode, loff_t index);
666int ecryptfs_parse_packet_length(unsigned char *data, size_t *size,
667 size_t *length_size);
668int ecryptfs_write_packet_length(char *dest, size_t size,
669 size_t *packet_size_length);
670#ifdef CONFIG_ECRYPT_FS_MESSAGING
671int ecryptfs_init_ecryptfs_miscdev(void);
672void ecryptfs_destroy_ecryptfs_miscdev(void);
673int ecryptfs_send_miscdev(char *data, size_t data_size,
674 struct ecryptfs_msg_ctx *msg_ctx, u8 msg_type,
675 u16 msg_flags, struct ecryptfs_daemon *daemon);
676void ecryptfs_msg_ctx_alloc_to_free(struct ecryptfs_msg_ctx *msg_ctx);
677int
678ecryptfs_spawn_daemon(struct ecryptfs_daemon **daemon, struct file *file);
679int ecryptfs_exorcise_daemon(struct ecryptfs_daemon *daemon);
680int ecryptfs_find_daemon_by_euid(struct ecryptfs_daemon **daemon);
681#endif
682int ecryptfs_init_kthread(void);
683void ecryptfs_destroy_kthread(void);
684int ecryptfs_privileged_open(struct file **lower_file,
685 struct dentry *lower_dentry,
686 struct vfsmount *lower_mnt,
687 const struct cred *cred);
688int ecryptfs_get_lower_file(struct dentry *dentry, struct inode *inode);
689void ecryptfs_put_lower_file(struct inode *inode);
690int
691ecryptfs_write_tag_70_packet(char *dest, size_t *remaining_bytes,
692 size_t *packet_size,
693 struct ecryptfs_mount_crypt_stat *mount_crypt_stat,
694 char *filename, size_t filename_size);
695int
696ecryptfs_parse_tag_70_packet(char **filename, size_t *filename_size,
697 size_t *packet_size,
698 struct ecryptfs_mount_crypt_stat *mount_crypt_stat,
699 char *data, size_t max_packet_size);
700int ecryptfs_set_f_namelen(long *namelen, long lower_namelen,
701 struct ecryptfs_mount_crypt_stat *mount_crypt_stat);
702int ecryptfs_derive_iv(char *iv, struct ecryptfs_crypt_stat *crypt_stat,
703 loff_t offset);
704
705extern const struct xattr_handler *ecryptfs_xattr_handlers[];
706
707#endif /* #ifndef ECRYPTFS_KERNEL_H */
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 <keys/encrypted-type.h>
33#include <linux/fs.h>
34#include <linux/fs_stack.h>
35#include <linux/namei.h>
36#include <linux/scatterlist.h>
37#include <linux/hash.h>
38#include <linux/nsproxy.h>
39#include <linux/backing-dev.h>
40#include <linux/ecryptfs.h>
41
42#define ECRYPTFS_DEFAULT_IV_BYTES 16
43#define ECRYPTFS_DEFAULT_EXTENT_SIZE 4096
44#define ECRYPTFS_MINIMUM_HEADER_EXTENT_SIZE 8192
45#define ECRYPTFS_DEFAULT_MSG_CTX_ELEMS 32
46#define ECRYPTFS_DEFAULT_SEND_TIMEOUT HZ
47#define ECRYPTFS_MAX_MSG_CTX_TTL (HZ*3)
48#define ECRYPTFS_DEFAULT_NUM_USERS 4
49#define ECRYPTFS_MAX_NUM_USERS 32768
50#define ECRYPTFS_XATTR_NAME "user.ecryptfs"
51
52void ecryptfs_dump_auth_tok(struct ecryptfs_auth_tok *auth_tok);
53extern void ecryptfs_to_hex(char *dst, char *src, size_t src_size);
54extern void ecryptfs_from_hex(char *dst, char *src, int dst_size);
55
56struct ecryptfs_key_record {
57 unsigned char type;
58 size_t enc_key_size;
59 unsigned char sig[ECRYPTFS_SIG_SIZE];
60 unsigned char enc_key[ECRYPTFS_MAX_ENCRYPTED_KEY_BYTES];
61};
62
63struct ecryptfs_auth_tok_list {
64 struct ecryptfs_auth_tok *auth_tok;
65 struct list_head list;
66};
67
68struct ecryptfs_crypt_stat;
69struct ecryptfs_mount_crypt_stat;
70
71struct ecryptfs_page_crypt_context {
72 struct page *page;
73#define ECRYPTFS_PREPARE_COMMIT_MODE 0
74#define ECRYPTFS_WRITEPAGE_MODE 1
75 unsigned int mode;
76 union {
77 struct file *lower_file;
78 struct writeback_control *wbc;
79 } param;
80};
81
82#if defined(CONFIG_ENCRYPTED_KEYS) || defined(CONFIG_ENCRYPTED_KEYS_MODULE)
83static inline struct ecryptfs_auth_tok *
84ecryptfs_get_encrypted_key_payload_data(struct key *key)
85{
86 if (key->type == &key_type_encrypted)
87 return (struct ecryptfs_auth_tok *)
88 (&((struct encrypted_key_payload *)key->payload.data)->payload_data);
89 else
90 return NULL;
91}
92
93static inline struct key *ecryptfs_get_encrypted_key(char *sig)
94{
95 return request_key(&key_type_encrypted, sig, NULL);
96}
97
98#else
99static inline struct ecryptfs_auth_tok *
100ecryptfs_get_encrypted_key_payload_data(struct key *key)
101{
102 return NULL;
103}
104
105static inline struct key *ecryptfs_get_encrypted_key(char *sig)
106{
107 return ERR_PTR(-ENOKEY);
108}
109
110#endif /* CONFIG_ENCRYPTED_KEYS */
111
112static inline struct ecryptfs_auth_tok *
113ecryptfs_get_key_payload_data(struct key *key)
114{
115 struct ecryptfs_auth_tok *auth_tok;
116
117 auth_tok = ecryptfs_get_encrypted_key_payload_data(key);
118 if (!auth_tok)
119 return (struct ecryptfs_auth_tok *)
120 (((struct user_key_payload *)key->payload.data)->data);
121 else
122 return auth_tok;
123}
124
125#define ECRYPTFS_MAX_KEYSET_SIZE 1024
126#define ECRYPTFS_MAX_CIPHER_NAME_SIZE 32
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
175struct ecryptfs_key_sig {
176 struct list_head crypt_stat_list;
177 char keysig[ECRYPTFS_SIG_SIZE_HEX + 1];
178};
179
180struct ecryptfs_filename {
181 struct list_head crypt_stat_list;
182#define ECRYPTFS_FILENAME_CONTAINS_DECRYPTED 0x00000001
183 u32 flags;
184 u32 seq_no;
185 char *filename;
186 char *encrypted_filename;
187 size_t filename_size;
188 size_t encrypted_filename_size;
189 char fnek_sig[ECRYPTFS_SIG_SIZE_HEX];
190 char dentry_name[ECRYPTFS_ENCRYPTED_DENTRY_NAME_LEN + 1];
191};
192
193/**
194 * This is the primary struct associated with each encrypted file.
195 *
196 * TODO: cache align/pack?
197 */
198struct ecryptfs_crypt_stat {
199#define ECRYPTFS_STRUCT_INITIALIZED 0x00000001
200#define ECRYPTFS_POLICY_APPLIED 0x00000002
201#define ECRYPTFS_ENCRYPTED 0x00000004
202#define ECRYPTFS_SECURITY_WARNING 0x00000008
203#define ECRYPTFS_ENABLE_HMAC 0x00000010
204#define ECRYPTFS_ENCRYPT_IV_PAGES 0x00000020
205#define ECRYPTFS_KEY_VALID 0x00000040
206#define ECRYPTFS_METADATA_IN_XATTR 0x00000080
207#define ECRYPTFS_VIEW_AS_ENCRYPTED 0x00000100
208#define ECRYPTFS_KEY_SET 0x00000200
209#define ECRYPTFS_ENCRYPT_FILENAMES 0x00000400
210#define ECRYPTFS_ENCFN_USE_MOUNT_FNEK 0x00000800
211#define ECRYPTFS_ENCFN_USE_FEK 0x00001000
212#define ECRYPTFS_UNLINK_SIGS 0x00002000
213#define ECRYPTFS_I_SIZE_INITIALIZED 0x00004000
214 u32 flags;
215 unsigned int file_version;
216 size_t iv_bytes;
217 size_t metadata_size;
218 size_t extent_size; /* Data extent size; default is 4096 */
219 size_t key_size;
220 size_t extent_shift;
221 unsigned int extent_mask;
222 struct ecryptfs_mount_crypt_stat *mount_crypt_stat;
223 struct crypto_blkcipher *tfm;
224 struct crypto_hash *hash_tfm; /* Crypto context for generating
225 * the initialization vectors */
226 unsigned char cipher[ECRYPTFS_MAX_CIPHER_NAME_SIZE];
227 unsigned char key[ECRYPTFS_MAX_KEY_BYTES];
228 unsigned char root_iv[ECRYPTFS_MAX_IV_BYTES];
229 struct list_head keysig_list;
230 struct mutex keysig_list_mutex;
231 struct mutex cs_tfm_mutex;
232 struct mutex cs_hash_tfm_mutex;
233 struct mutex cs_mutex;
234};
235
236/* inode private data. */
237struct ecryptfs_inode_info {
238 struct inode vfs_inode;
239 struct inode *wii_inode;
240 struct mutex lower_file_mutex;
241 atomic_t lower_file_count;
242 struct file *lower_file;
243 struct ecryptfs_crypt_stat crypt_stat;
244};
245
246/* dentry private data. Each dentry must keep track of a lower
247 * vfsmount too. */
248struct ecryptfs_dentry_info {
249 struct path lower_path;
250 struct ecryptfs_crypt_stat *crypt_stat;
251};
252
253/**
254 * ecryptfs_global_auth_tok - A key used to encrypt all new files under the mountpoint
255 * @flags: Status flags
256 * @mount_crypt_stat_list: These auth_toks hang off the mount-wide
257 * cryptographic context. Every time a new
258 * inode comes into existence, eCryptfs copies
259 * the auth_toks on that list to the set of
260 * auth_toks on the inode's crypt_stat
261 * @global_auth_tok_key: The key from the user's keyring for the sig
262 * @global_auth_tok: The key contents
263 * @sig: The key identifier
264 *
265 * ecryptfs_global_auth_tok structs refer to authentication token keys
266 * in the user keyring that apply to newly created files. A list of
267 * these objects hangs off of the mount_crypt_stat struct for any
268 * given eCryptfs mount. This struct maintains a reference to both the
269 * key contents and the key itself so that the key can be put on
270 * unmount.
271 */
272struct ecryptfs_global_auth_tok {
273#define ECRYPTFS_AUTH_TOK_INVALID 0x00000001
274#define ECRYPTFS_AUTH_TOK_FNEK 0x00000002
275 u32 flags;
276 struct list_head mount_crypt_stat_list;
277 struct key *global_auth_tok_key;
278 unsigned char sig[ECRYPTFS_SIG_SIZE_HEX + 1];
279};
280
281/**
282 * ecryptfs_key_tfm - Persistent key tfm
283 * @key_tfm: crypto API handle to the key
284 * @key_size: Key size in bytes
285 * @key_tfm_mutex: Mutex to ensure only one operation in eCryptfs is
286 * using the persistent TFM at any point in time
287 * @key_tfm_list: Handle to hang this off the module-wide TFM list
288 * @cipher_name: String name for the cipher for this TFM
289 *
290 * Typically, eCryptfs will use the same ciphers repeatedly throughout
291 * the course of its operations. In order to avoid unnecessarily
292 * destroying and initializing the same cipher repeatedly, eCryptfs
293 * keeps a list of crypto API contexts around to use when needed.
294 */
295struct ecryptfs_key_tfm {
296 struct crypto_blkcipher *key_tfm;
297 size_t key_size;
298 struct mutex key_tfm_mutex;
299 struct list_head key_tfm_list;
300 unsigned char cipher_name[ECRYPTFS_MAX_CIPHER_NAME_SIZE + 1];
301};
302
303extern struct mutex key_tfm_list_mutex;
304
305/**
306 * This struct is to enable a mount-wide passphrase/salt combo. This
307 * is more or less a stopgap to provide similar functionality to other
308 * crypto filesystems like EncFS or CFS until full policy support is
309 * implemented in eCryptfs.
310 */
311struct ecryptfs_mount_crypt_stat {
312 /* Pointers to memory we do not own, do not free these */
313#define ECRYPTFS_PLAINTEXT_PASSTHROUGH_ENABLED 0x00000001
314#define ECRYPTFS_XATTR_METADATA_ENABLED 0x00000002
315#define ECRYPTFS_ENCRYPTED_VIEW_ENABLED 0x00000004
316#define ECRYPTFS_MOUNT_CRYPT_STAT_INITIALIZED 0x00000008
317#define ECRYPTFS_GLOBAL_ENCRYPT_FILENAMES 0x00000010
318#define ECRYPTFS_GLOBAL_ENCFN_USE_MOUNT_FNEK 0x00000020
319#define ECRYPTFS_GLOBAL_ENCFN_USE_FEK 0x00000040
320#define ECRYPTFS_GLOBAL_MOUNT_AUTH_TOK_ONLY 0x00000080
321 u32 flags;
322 struct list_head global_auth_tok_list;
323 struct mutex global_auth_tok_list_mutex;
324 size_t global_default_cipher_key_size;
325 size_t global_default_fn_cipher_key_bytes;
326 unsigned char global_default_cipher_name[ECRYPTFS_MAX_CIPHER_NAME_SIZE
327 + 1];
328 unsigned char global_default_fn_cipher_name[
329 ECRYPTFS_MAX_CIPHER_NAME_SIZE + 1];
330 char global_default_fnek_sig[ECRYPTFS_SIG_SIZE_HEX + 1];
331};
332
333/* superblock private data. */
334struct ecryptfs_sb_info {
335 struct super_block *wsi_sb;
336 struct ecryptfs_mount_crypt_stat mount_crypt_stat;
337 struct backing_dev_info bdi;
338};
339
340/* file private data. */
341struct ecryptfs_file_info {
342 struct file *wfi_file;
343 struct ecryptfs_crypt_stat *crypt_stat;
344};
345
346/* auth_tok <=> encrypted_session_key mappings */
347struct ecryptfs_auth_tok_list_item {
348 unsigned char encrypted_session_key[ECRYPTFS_MAX_KEY_BYTES];
349 struct list_head list;
350 struct ecryptfs_auth_tok auth_tok;
351};
352
353struct ecryptfs_message {
354 /* Can never be greater than ecryptfs_message_buf_len */
355 /* Used to find the parent msg_ctx */
356 /* Inherits from msg_ctx->index */
357 u32 index;
358 u32 data_len;
359 u8 data[];
360};
361
362struct ecryptfs_msg_ctx {
363#define ECRYPTFS_MSG_CTX_STATE_FREE 0x01
364#define ECRYPTFS_MSG_CTX_STATE_PENDING 0x02
365#define ECRYPTFS_MSG_CTX_STATE_DONE 0x03
366#define ECRYPTFS_MSG_CTX_STATE_NO_REPLY 0x04
367 u8 state;
368#define ECRYPTFS_MSG_HELO 100
369#define ECRYPTFS_MSG_QUIT 101
370#define ECRYPTFS_MSG_REQUEST 102
371#define ECRYPTFS_MSG_RESPONSE 103
372 u8 type;
373 u32 index;
374 /* Counter converts to a sequence number. Each message sent
375 * out for which we expect a response has an associated
376 * sequence number. The response must have the same sequence
377 * number as the counter for the msg_stc for the message to be
378 * valid. */
379 u32 counter;
380 size_t msg_size;
381 struct ecryptfs_message *msg;
382 struct task_struct *task;
383 struct list_head node;
384 struct list_head daemon_out_list;
385 struct mutex mux;
386};
387
388struct ecryptfs_daemon;
389
390struct ecryptfs_daemon {
391#define ECRYPTFS_DAEMON_IN_READ 0x00000001
392#define ECRYPTFS_DAEMON_IN_POLL 0x00000002
393#define ECRYPTFS_DAEMON_ZOMBIE 0x00000004
394#define ECRYPTFS_DAEMON_MISCDEV_OPEN 0x00000008
395 u32 flags;
396 u32 num_queued_msg_ctx;
397 struct pid *pid;
398 uid_t euid;
399 struct user_namespace *user_ns;
400 struct task_struct *task;
401 struct mutex mux;
402 struct list_head msg_ctx_out_queue;
403 wait_queue_head_t wait;
404 struct hlist_node euid_chain;
405};
406
407extern struct mutex ecryptfs_daemon_hash_mux;
408
409static inline size_t
410ecryptfs_lower_header_size(struct ecryptfs_crypt_stat *crypt_stat)
411{
412 if (crypt_stat->flags & ECRYPTFS_METADATA_IN_XATTR)
413 return 0;
414 return crypt_stat->metadata_size;
415}
416
417static inline struct ecryptfs_file_info *
418ecryptfs_file_to_private(struct file *file)
419{
420 return file->private_data;
421}
422
423static inline void
424ecryptfs_set_file_private(struct file *file,
425 struct ecryptfs_file_info *file_info)
426{
427 file->private_data = file_info;
428}
429
430static inline struct file *ecryptfs_file_to_lower(struct file *file)
431{
432 return ((struct ecryptfs_file_info *)file->private_data)->wfi_file;
433}
434
435static inline void
436ecryptfs_set_file_lower(struct file *file, struct file *lower_file)
437{
438 ((struct ecryptfs_file_info *)file->private_data)->wfi_file =
439 lower_file;
440}
441
442static inline struct ecryptfs_inode_info *
443ecryptfs_inode_to_private(struct inode *inode)
444{
445 return container_of(inode, struct ecryptfs_inode_info, vfs_inode);
446}
447
448static inline struct inode *ecryptfs_inode_to_lower(struct inode *inode)
449{
450 return ecryptfs_inode_to_private(inode)->wii_inode;
451}
452
453static inline void
454ecryptfs_set_inode_lower(struct inode *inode, struct inode *lower_inode)
455{
456 ecryptfs_inode_to_private(inode)->wii_inode = lower_inode;
457}
458
459static inline struct ecryptfs_sb_info *
460ecryptfs_superblock_to_private(struct super_block *sb)
461{
462 return (struct ecryptfs_sb_info *)sb->s_fs_info;
463}
464
465static inline void
466ecryptfs_set_superblock_private(struct super_block *sb,
467 struct ecryptfs_sb_info *sb_info)
468{
469 sb->s_fs_info = sb_info;
470}
471
472static inline struct super_block *
473ecryptfs_superblock_to_lower(struct super_block *sb)
474{
475 return ((struct ecryptfs_sb_info *)sb->s_fs_info)->wsi_sb;
476}
477
478static inline void
479ecryptfs_set_superblock_lower(struct super_block *sb,
480 struct super_block *lower_sb)
481{
482 ((struct ecryptfs_sb_info *)sb->s_fs_info)->wsi_sb = lower_sb;
483}
484
485static inline struct ecryptfs_dentry_info *
486ecryptfs_dentry_to_private(struct dentry *dentry)
487{
488 return (struct ecryptfs_dentry_info *)dentry->d_fsdata;
489}
490
491static inline void
492ecryptfs_set_dentry_private(struct dentry *dentry,
493 struct ecryptfs_dentry_info *dentry_info)
494{
495 dentry->d_fsdata = dentry_info;
496}
497
498static inline struct dentry *
499ecryptfs_dentry_to_lower(struct dentry *dentry)
500{
501 return ((struct ecryptfs_dentry_info *)dentry->d_fsdata)->lower_path.dentry;
502}
503
504static inline void
505ecryptfs_set_dentry_lower(struct dentry *dentry, struct dentry *lower_dentry)
506{
507 ((struct ecryptfs_dentry_info *)dentry->d_fsdata)->lower_path.dentry =
508 lower_dentry;
509}
510
511static inline struct vfsmount *
512ecryptfs_dentry_to_lower_mnt(struct dentry *dentry)
513{
514 return ((struct ecryptfs_dentry_info *)dentry->d_fsdata)->lower_path.mnt;
515}
516
517static inline void
518ecryptfs_set_dentry_lower_mnt(struct dentry *dentry, struct vfsmount *lower_mnt)
519{
520 ((struct ecryptfs_dentry_info *)dentry->d_fsdata)->lower_path.mnt =
521 lower_mnt;
522}
523
524#define ecryptfs_printk(type, fmt, arg...) \
525 __ecryptfs_printk(type "%s: " fmt, __func__, ## arg);
526__printf(1, 2)
527void __ecryptfs_printk(const char *fmt, ...);
528
529extern const struct file_operations ecryptfs_main_fops;
530extern const struct file_operations ecryptfs_dir_fops;
531extern const struct inode_operations ecryptfs_main_iops;
532extern const struct inode_operations ecryptfs_dir_iops;
533extern const struct inode_operations ecryptfs_symlink_iops;
534extern const struct super_operations ecryptfs_sops;
535extern const struct dentry_operations ecryptfs_dops;
536extern const struct address_space_operations ecryptfs_aops;
537extern int ecryptfs_verbosity;
538extern unsigned int ecryptfs_message_buf_len;
539extern signed long ecryptfs_message_wait_timeout;
540extern unsigned int ecryptfs_number_of_users;
541
542extern struct kmem_cache *ecryptfs_auth_tok_list_item_cache;
543extern struct kmem_cache *ecryptfs_file_info_cache;
544extern struct kmem_cache *ecryptfs_dentry_info_cache;
545extern struct kmem_cache *ecryptfs_inode_info_cache;
546extern struct kmem_cache *ecryptfs_sb_info_cache;
547extern struct kmem_cache *ecryptfs_header_cache;
548extern struct kmem_cache *ecryptfs_xattr_cache;
549extern struct kmem_cache *ecryptfs_key_record_cache;
550extern struct kmem_cache *ecryptfs_key_sig_cache;
551extern struct kmem_cache *ecryptfs_global_auth_tok_cache;
552extern struct kmem_cache *ecryptfs_key_tfm_cache;
553extern struct kmem_cache *ecryptfs_open_req_cache;
554
555struct ecryptfs_open_req {
556#define ECRYPTFS_REQ_PROCESSED 0x00000001
557#define ECRYPTFS_REQ_DROPPED 0x00000002
558#define ECRYPTFS_REQ_ZOMBIE 0x00000004
559 u32 flags;
560 struct file **lower_file;
561 struct dentry *lower_dentry;
562 struct vfsmount *lower_mnt;
563 wait_queue_head_t wait;
564 struct mutex mux;
565 struct list_head kthread_ctl_list;
566};
567
568struct inode *ecryptfs_get_inode(struct inode *lower_inode,
569 struct super_block *sb);
570void ecryptfs_i_size_init(const char *page_virt, struct inode *inode);
571int ecryptfs_decode_and_decrypt_filename(char **decrypted_name,
572 size_t *decrypted_name_size,
573 struct dentry *ecryptfs_dentry,
574 const char *name, size_t name_size);
575int ecryptfs_fill_zeros(struct file *file, loff_t new_length);
576int ecryptfs_encrypt_and_encode_filename(
577 char **encoded_name,
578 size_t *encoded_name_size,
579 struct ecryptfs_crypt_stat *crypt_stat,
580 struct ecryptfs_mount_crypt_stat *mount_crypt_stat,
581 const char *name, size_t name_size);
582struct dentry *ecryptfs_lower_dentry(struct dentry *this_dentry);
583void ecryptfs_dump_hex(char *data, int bytes);
584int virt_to_scatterlist(const void *addr, int size, struct scatterlist *sg,
585 int sg_size);
586int ecryptfs_compute_root_iv(struct ecryptfs_crypt_stat *crypt_stat);
587void ecryptfs_rotate_iv(unsigned char *iv);
588void ecryptfs_init_crypt_stat(struct ecryptfs_crypt_stat *crypt_stat);
589void ecryptfs_destroy_crypt_stat(struct ecryptfs_crypt_stat *crypt_stat);
590void ecryptfs_destroy_mount_crypt_stat(
591 struct ecryptfs_mount_crypt_stat *mount_crypt_stat);
592int ecryptfs_init_crypt_ctx(struct ecryptfs_crypt_stat *crypt_stat);
593int ecryptfs_write_inode_size_to_metadata(struct inode *ecryptfs_inode);
594int ecryptfs_encrypt_page(struct page *page);
595int ecryptfs_decrypt_page(struct page *page);
596int ecryptfs_write_metadata(struct dentry *ecryptfs_dentry,
597 struct inode *ecryptfs_inode);
598int ecryptfs_read_metadata(struct dentry *ecryptfs_dentry);
599int ecryptfs_new_file_context(struct inode *ecryptfs_inode);
600void ecryptfs_write_crypt_stat_flags(char *page_virt,
601 struct ecryptfs_crypt_stat *crypt_stat,
602 size_t *written);
603int ecryptfs_read_and_validate_header_region(struct inode *inode);
604int ecryptfs_read_and_validate_xattr_region(struct dentry *dentry,
605 struct inode *inode);
606u8 ecryptfs_code_for_cipher_string(char *cipher_name, size_t key_bytes);
607int ecryptfs_cipher_code_to_string(char *str, u8 cipher_code);
608void ecryptfs_set_default_sizes(struct ecryptfs_crypt_stat *crypt_stat);
609int 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);
613int
614ecryptfs_parse_packet_set(struct ecryptfs_crypt_stat *crypt_stat,
615 unsigned char *src, struct dentry *ecryptfs_dentry);
616int ecryptfs_truncate(struct dentry *dentry, loff_t new_length);
617ssize_t
618ecryptfs_getxattr_lower(struct dentry *lower_dentry, const char *name,
619 void *value, size_t size);
620int
621ecryptfs_setxattr(struct dentry *dentry, const char *name, const void *value,
622 size_t size, int flags);
623int ecryptfs_read_xattr_region(char *page_virt, struct inode *ecryptfs_inode);
624int ecryptfs_process_helo(uid_t euid, struct user_namespace *user_ns,
625 struct pid *pid);
626int ecryptfs_process_quit(uid_t euid, struct user_namespace *user_ns,
627 struct pid *pid);
628int ecryptfs_process_response(struct ecryptfs_message *msg, uid_t euid,
629 struct user_namespace *user_ns, struct pid *pid,
630 u32 seq);
631int ecryptfs_send_message(char *data, int data_len,
632 struct ecryptfs_msg_ctx **msg_ctx);
633int ecryptfs_wait_for_response(struct ecryptfs_msg_ctx *msg_ctx,
634 struct ecryptfs_message **emsg);
635int ecryptfs_init_messaging(void);
636void ecryptfs_release_messaging(void);
637
638void
639ecryptfs_write_header_metadata(char *virt,
640 struct ecryptfs_crypt_stat *crypt_stat,
641 size_t *written);
642int ecryptfs_add_keysig(struct ecryptfs_crypt_stat *crypt_stat, char *sig);
643int
644ecryptfs_add_global_auth_tok(struct ecryptfs_mount_crypt_stat *mount_crypt_stat,
645 char *sig, u32 global_auth_tok_flags);
646int ecryptfs_get_global_auth_tok_for_sig(
647 struct ecryptfs_global_auth_tok **global_auth_tok,
648 struct ecryptfs_mount_crypt_stat *mount_crypt_stat, char *sig);
649int
650ecryptfs_add_new_key_tfm(struct ecryptfs_key_tfm **key_tfm, char *cipher_name,
651 size_t key_size);
652int ecryptfs_init_crypto(void);
653int ecryptfs_destroy_crypto(void);
654int ecryptfs_tfm_exists(char *cipher_name, struct ecryptfs_key_tfm **key_tfm);
655int ecryptfs_get_tfm_and_mutex_for_cipher_name(struct crypto_blkcipher **tfm,
656 struct mutex **tfm_mutex,
657 char *cipher_name);
658int ecryptfs_keyring_auth_tok_for_sig(struct key **auth_tok_key,
659 struct ecryptfs_auth_tok **auth_tok,
660 char *sig);
661int ecryptfs_write_lower(struct inode *ecryptfs_inode, char *data,
662 loff_t offset, size_t size);
663int ecryptfs_write_lower_page_segment(struct inode *ecryptfs_inode,
664 struct page *page_for_lower,
665 size_t offset_in_page, size_t size);
666int ecryptfs_write(struct inode *inode, char *data, loff_t offset, size_t size);
667int ecryptfs_read_lower(char *data, loff_t offset, size_t size,
668 struct inode *ecryptfs_inode);
669int ecryptfs_read_lower_page_segment(struct page *page_for_ecryptfs,
670 pgoff_t page_index,
671 size_t offset_in_page, size_t size,
672 struct inode *ecryptfs_inode);
673struct page *ecryptfs_get_locked_page(struct inode *inode, loff_t index);
674int ecryptfs_exorcise_daemon(struct ecryptfs_daemon *daemon);
675int ecryptfs_find_daemon_by_euid(struct ecryptfs_daemon **daemon, uid_t euid,
676 struct user_namespace *user_ns);
677int ecryptfs_parse_packet_length(unsigned char *data, size_t *size,
678 size_t *length_size);
679int ecryptfs_write_packet_length(char *dest, size_t size,
680 size_t *packet_size_length);
681int ecryptfs_init_ecryptfs_miscdev(void);
682void ecryptfs_destroy_ecryptfs_miscdev(void);
683int ecryptfs_send_miscdev(char *data, size_t data_size,
684 struct ecryptfs_msg_ctx *msg_ctx, u8 msg_type,
685 u16 msg_flags, struct ecryptfs_daemon *daemon);
686void ecryptfs_msg_ctx_alloc_to_free(struct ecryptfs_msg_ctx *msg_ctx);
687int
688ecryptfs_spawn_daemon(struct ecryptfs_daemon **daemon, uid_t euid,
689 struct user_namespace *user_ns, struct pid *pid);
690int ecryptfs_init_kthread(void);
691void ecryptfs_destroy_kthread(void);
692int ecryptfs_privileged_open(struct file **lower_file,
693 struct dentry *lower_dentry,
694 struct vfsmount *lower_mnt,
695 const struct cred *cred);
696int ecryptfs_get_lower_file(struct dentry *dentry, struct inode *inode);
697void ecryptfs_put_lower_file(struct inode *inode);
698int
699ecryptfs_write_tag_70_packet(char *dest, size_t *remaining_bytes,
700 size_t *packet_size,
701 struct ecryptfs_mount_crypt_stat *mount_crypt_stat,
702 char *filename, size_t filename_size);
703int
704ecryptfs_parse_tag_70_packet(char **filename, size_t *filename_size,
705 size_t *packet_size,
706 struct ecryptfs_mount_crypt_stat *mount_crypt_stat,
707 char *data, size_t max_packet_size);
708int ecryptfs_set_f_namelen(long *namelen, long lower_namelen,
709 struct ecryptfs_mount_crypt_stat *mount_crypt_stat);
710int ecryptfs_derive_iv(char *iv, struct ecryptfs_crypt_stat *crypt_stat,
711 loff_t offset);
712
713#endif /* #ifndef ECRYPTFS_KERNEL_H */