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1/* SPDX-License-Identifier: GPL-2.0 */
2/*
3 * fscrypt_private.h
4 *
5 * Copyright (C) 2015, Google, Inc.
6 *
7 * This contains encryption key functions.
8 *
9 * Written by Michael Halcrow, Ildar Muslukhov, and Uday Savagaonkar, 2015.
10 */
11
12#ifndef _FSCRYPT_PRIVATE_H
13#define _FSCRYPT_PRIVATE_H
14
15#define __FS_HAS_ENCRYPTION 1
16#include <linux/fscrypt.h>
17#include <crypto/hash.h>
18
19/* Encryption parameters */
20#define FS_IV_SIZE 16
21#define FS_AES_128_ECB_KEY_SIZE 16
22#define FS_AES_128_CBC_KEY_SIZE 16
23#define FS_AES_128_CTS_KEY_SIZE 16
24#define FS_AES_256_GCM_KEY_SIZE 32
25#define FS_AES_256_CBC_KEY_SIZE 32
26#define FS_AES_256_CTS_KEY_SIZE 32
27#define FS_AES_256_XTS_KEY_SIZE 64
28
29#define FS_KEY_DERIVATION_NONCE_SIZE 16
30
31/**
32 * Encryption context for inode
33 *
34 * Protector format:
35 * 1 byte: Protector format (1 = this version)
36 * 1 byte: File contents encryption mode
37 * 1 byte: File names encryption mode
38 * 1 byte: Flags
39 * 8 bytes: Master Key descriptor
40 * 16 bytes: Encryption Key derivation nonce
41 */
42struct fscrypt_context {
43 u8 format;
44 u8 contents_encryption_mode;
45 u8 filenames_encryption_mode;
46 u8 flags;
47 u8 master_key_descriptor[FS_KEY_DESCRIPTOR_SIZE];
48 u8 nonce[FS_KEY_DERIVATION_NONCE_SIZE];
49} __packed;
50
51#define FS_ENCRYPTION_CONTEXT_FORMAT_V1 1
52
53/**
54 * For encrypted symlinks, the ciphertext length is stored at the beginning
55 * of the string in little-endian format.
56 */
57struct fscrypt_symlink_data {
58 __le16 len;
59 char encrypted_path[1];
60} __packed;
61
62/*
63 * A pointer to this structure is stored in the file system's in-core
64 * representation of an inode.
65 */
66struct fscrypt_info {
67 u8 ci_data_mode;
68 u8 ci_filename_mode;
69 u8 ci_flags;
70 struct crypto_skcipher *ci_ctfm;
71 struct crypto_cipher *ci_essiv_tfm;
72 u8 ci_master_key[FS_KEY_DESCRIPTOR_SIZE];
73};
74
75typedef enum {
76 FS_DECRYPT = 0,
77 FS_ENCRYPT,
78} fscrypt_direction_t;
79
80#define FS_CTX_REQUIRES_FREE_ENCRYPT_FL 0x00000001
81#define FS_CTX_HAS_BOUNCE_BUFFER_FL 0x00000002
82
83static inline bool fscrypt_valid_enc_modes(u32 contents_mode,
84 u32 filenames_mode)
85{
86 if (contents_mode == FS_ENCRYPTION_MODE_AES_128_CBC &&
87 filenames_mode == FS_ENCRYPTION_MODE_AES_128_CTS)
88 return true;
89
90 if (contents_mode == FS_ENCRYPTION_MODE_AES_256_XTS &&
91 filenames_mode == FS_ENCRYPTION_MODE_AES_256_CTS)
92 return true;
93
94 return false;
95}
96
97/* crypto.c */
98extern struct kmem_cache *fscrypt_info_cachep;
99extern int fscrypt_initialize(unsigned int cop_flags);
100extern struct workqueue_struct *fscrypt_read_workqueue;
101extern int fscrypt_do_page_crypto(const struct inode *inode,
102 fscrypt_direction_t rw, u64 lblk_num,
103 struct page *src_page,
104 struct page *dest_page,
105 unsigned int len, unsigned int offs,
106 gfp_t gfp_flags);
107extern struct page *fscrypt_alloc_bounce_page(struct fscrypt_ctx *ctx,
108 gfp_t gfp_flags);
109
110/* fname.c */
111extern int fname_encrypt(struct inode *inode, const struct qstr *iname,
112 u8 *out, unsigned int olen);
113extern bool fscrypt_fname_encrypted_size(const struct inode *inode,
114 u32 orig_len, u32 max_len,
115 u32 *encrypted_len_ret);
116
117/* keyinfo.c */
118extern void __exit fscrypt_essiv_cleanup(void);
119
120#endif /* _FSCRYPT_PRIVATE_H */
1/* SPDX-License-Identifier: GPL-2.0 */
2/*
3 * fscrypt_private.h
4 *
5 * Copyright (C) 2015, Google, Inc.
6 *
7 * Originally written by Michael Halcrow, Ildar Muslukhov, and Uday Savagaonkar.
8 * Heavily modified since then.
9 */
10
11#ifndef _FSCRYPT_PRIVATE_H
12#define _FSCRYPT_PRIVATE_H
13
14#include <linux/fscrypt.h>
15#include <linux/siphash.h>
16#include <crypto/hash.h>
17#include <linux/blk-crypto.h>
18
19#define CONST_STRLEN(str) (sizeof(str) - 1)
20
21#define FSCRYPT_FILE_NONCE_SIZE 16
22
23#define FSCRYPT_MIN_KEY_SIZE 16
24
25#define FSCRYPT_CONTEXT_V1 1
26#define FSCRYPT_CONTEXT_V2 2
27
28struct fscrypt_context_v1 {
29 u8 version; /* FSCRYPT_CONTEXT_V1 */
30 u8 contents_encryption_mode;
31 u8 filenames_encryption_mode;
32 u8 flags;
33 u8 master_key_descriptor[FSCRYPT_KEY_DESCRIPTOR_SIZE];
34 u8 nonce[FSCRYPT_FILE_NONCE_SIZE];
35};
36
37struct fscrypt_context_v2 {
38 u8 version; /* FSCRYPT_CONTEXT_V2 */
39 u8 contents_encryption_mode;
40 u8 filenames_encryption_mode;
41 u8 flags;
42 u8 __reserved[4];
43 u8 master_key_identifier[FSCRYPT_KEY_IDENTIFIER_SIZE];
44 u8 nonce[FSCRYPT_FILE_NONCE_SIZE];
45};
46
47/*
48 * fscrypt_context - the encryption context of an inode
49 *
50 * This is the on-disk equivalent of an fscrypt_policy, stored alongside each
51 * encrypted file usually in a hidden extended attribute. It contains the
52 * fields from the fscrypt_policy, in order to identify the encryption algorithm
53 * and key with which the file is encrypted. It also contains a nonce that was
54 * randomly generated by fscrypt itself; this is used as KDF input or as a tweak
55 * to cause different files to be encrypted differently.
56 */
57union fscrypt_context {
58 u8 version;
59 struct fscrypt_context_v1 v1;
60 struct fscrypt_context_v2 v2;
61};
62
63/*
64 * Return the size expected for the given fscrypt_context based on its version
65 * number, or 0 if the context version is unrecognized.
66 */
67static inline int fscrypt_context_size(const union fscrypt_context *ctx)
68{
69 switch (ctx->version) {
70 case FSCRYPT_CONTEXT_V1:
71 BUILD_BUG_ON(sizeof(ctx->v1) != 28);
72 return sizeof(ctx->v1);
73 case FSCRYPT_CONTEXT_V2:
74 BUILD_BUG_ON(sizeof(ctx->v2) != 40);
75 return sizeof(ctx->v2);
76 }
77 return 0;
78}
79
80/* Check whether an fscrypt_context has a recognized version number and size */
81static inline bool fscrypt_context_is_valid(const union fscrypt_context *ctx,
82 int ctx_size)
83{
84 return ctx_size >= 1 && ctx_size == fscrypt_context_size(ctx);
85}
86
87/* Retrieve the context's nonce, assuming the context was already validated */
88static inline const u8 *fscrypt_context_nonce(const union fscrypt_context *ctx)
89{
90 switch (ctx->version) {
91 case FSCRYPT_CONTEXT_V1:
92 return ctx->v1.nonce;
93 case FSCRYPT_CONTEXT_V2:
94 return ctx->v2.nonce;
95 }
96 WARN_ON(1);
97 return NULL;
98}
99
100#undef fscrypt_policy
101union fscrypt_policy {
102 u8 version;
103 struct fscrypt_policy_v1 v1;
104 struct fscrypt_policy_v2 v2;
105};
106
107/*
108 * Return the size expected for the given fscrypt_policy based on its version
109 * number, or 0 if the policy version is unrecognized.
110 */
111static inline int fscrypt_policy_size(const union fscrypt_policy *policy)
112{
113 switch (policy->version) {
114 case FSCRYPT_POLICY_V1:
115 return sizeof(policy->v1);
116 case FSCRYPT_POLICY_V2:
117 return sizeof(policy->v2);
118 }
119 return 0;
120}
121
122/* Return the contents encryption mode of a valid encryption policy */
123static inline u8
124fscrypt_policy_contents_mode(const union fscrypt_policy *policy)
125{
126 switch (policy->version) {
127 case FSCRYPT_POLICY_V1:
128 return policy->v1.contents_encryption_mode;
129 case FSCRYPT_POLICY_V2:
130 return policy->v2.contents_encryption_mode;
131 }
132 BUG();
133}
134
135/* Return the filenames encryption mode of a valid encryption policy */
136static inline u8
137fscrypt_policy_fnames_mode(const union fscrypt_policy *policy)
138{
139 switch (policy->version) {
140 case FSCRYPT_POLICY_V1:
141 return policy->v1.filenames_encryption_mode;
142 case FSCRYPT_POLICY_V2:
143 return policy->v2.filenames_encryption_mode;
144 }
145 BUG();
146}
147
148/* Return the flags (FSCRYPT_POLICY_FLAG*) of a valid encryption policy */
149static inline u8
150fscrypt_policy_flags(const union fscrypt_policy *policy)
151{
152 switch (policy->version) {
153 case FSCRYPT_POLICY_V1:
154 return policy->v1.flags;
155 case FSCRYPT_POLICY_V2:
156 return policy->v2.flags;
157 }
158 BUG();
159}
160
161/*
162 * For encrypted symlinks, the ciphertext length is stored at the beginning
163 * of the string in little-endian format.
164 */
165struct fscrypt_symlink_data {
166 __le16 len;
167 char encrypted_path[1];
168} __packed;
169
170/**
171 * struct fscrypt_prepared_key - a key prepared for actual encryption/decryption
172 * @tfm: crypto API transform object
173 * @blk_key: key for blk-crypto
174 *
175 * Normally only one of the fields will be non-NULL.
176 */
177struct fscrypt_prepared_key {
178 struct crypto_skcipher *tfm;
179#ifdef CONFIG_FS_ENCRYPTION_INLINE_CRYPT
180 struct fscrypt_blk_crypto_key *blk_key;
181#endif
182};
183
184/*
185 * fscrypt_info - the "encryption key" for an inode
186 *
187 * When an encrypted file's key is made available, an instance of this struct is
188 * allocated and stored in ->i_crypt_info. Once created, it remains until the
189 * inode is evicted.
190 */
191struct fscrypt_info {
192
193 /* The key in a form prepared for actual encryption/decryption */
194 struct fscrypt_prepared_key ci_enc_key;
195
196 /* True if ci_enc_key should be freed when this fscrypt_info is freed */
197 bool ci_owns_key;
198
199#ifdef CONFIG_FS_ENCRYPTION_INLINE_CRYPT
200 /*
201 * True if this inode will use inline encryption (blk-crypto) instead of
202 * the traditional filesystem-layer encryption.
203 */
204 bool ci_inlinecrypt;
205#endif
206
207 /*
208 * Encryption mode used for this inode. It corresponds to either the
209 * contents or filenames encryption mode, depending on the inode type.
210 */
211 struct fscrypt_mode *ci_mode;
212
213 /* Back-pointer to the inode */
214 struct inode *ci_inode;
215
216 /*
217 * The master key with which this inode was unlocked (decrypted). This
218 * will be NULL if the master key was found in a process-subscribed
219 * keyring rather than in the filesystem-level keyring.
220 */
221 struct key *ci_master_key;
222
223 /*
224 * Link in list of inodes that were unlocked with the master key.
225 * Only used when ->ci_master_key is set.
226 */
227 struct list_head ci_master_key_link;
228
229 /*
230 * If non-NULL, then encryption is done using the master key directly
231 * and ci_enc_key will equal ci_direct_key->dk_key.
232 */
233 struct fscrypt_direct_key *ci_direct_key;
234
235 /*
236 * This inode's hash key for filenames. This is a 128-bit SipHash-2-4
237 * key. This is only set for directories that use a keyed dirhash over
238 * the plaintext filenames -- currently just casefolded directories.
239 */
240 siphash_key_t ci_dirhash_key;
241 bool ci_dirhash_key_initialized;
242
243 /* The encryption policy used by this inode */
244 union fscrypt_policy ci_policy;
245
246 /* This inode's nonce, copied from the fscrypt_context */
247 u8 ci_nonce[FSCRYPT_FILE_NONCE_SIZE];
248
249 /* Hashed inode number. Only set for IV_INO_LBLK_32 */
250 u32 ci_hashed_ino;
251};
252
253typedef enum {
254 FS_DECRYPT = 0,
255 FS_ENCRYPT,
256} fscrypt_direction_t;
257
258/* crypto.c */
259extern struct kmem_cache *fscrypt_info_cachep;
260int fscrypt_initialize(unsigned int cop_flags);
261int fscrypt_crypt_block(const struct inode *inode, fscrypt_direction_t rw,
262 u64 lblk_num, struct page *src_page,
263 struct page *dest_page, unsigned int len,
264 unsigned int offs, gfp_t gfp_flags);
265struct page *fscrypt_alloc_bounce_page(gfp_t gfp_flags);
266
267void __printf(3, 4) __cold
268fscrypt_msg(const struct inode *inode, const char *level, const char *fmt, ...);
269
270#define fscrypt_warn(inode, fmt, ...) \
271 fscrypt_msg((inode), KERN_WARNING, fmt, ##__VA_ARGS__)
272#define fscrypt_err(inode, fmt, ...) \
273 fscrypt_msg((inode), KERN_ERR, fmt, ##__VA_ARGS__)
274
275#define FSCRYPT_MAX_IV_SIZE 32
276
277union fscrypt_iv {
278 struct {
279 /* logical block number within the file */
280 __le64 lblk_num;
281
282 /* per-file nonce; only set in DIRECT_KEY mode */
283 u8 nonce[FSCRYPT_FILE_NONCE_SIZE];
284 };
285 u8 raw[FSCRYPT_MAX_IV_SIZE];
286 __le64 dun[FSCRYPT_MAX_IV_SIZE / sizeof(__le64)];
287};
288
289void fscrypt_generate_iv(union fscrypt_iv *iv, u64 lblk_num,
290 const struct fscrypt_info *ci);
291
292/* fname.c */
293int fscrypt_fname_encrypt(const struct inode *inode, const struct qstr *iname,
294 u8 *out, unsigned int olen);
295bool fscrypt_fname_encrypted_size(const struct inode *inode, u32 orig_len,
296 u32 max_len, u32 *encrypted_len_ret);
297extern const struct dentry_operations fscrypt_d_ops;
298
299/* hkdf.c */
300
301struct fscrypt_hkdf {
302 struct crypto_shash *hmac_tfm;
303};
304
305int fscrypt_init_hkdf(struct fscrypt_hkdf *hkdf, const u8 *master_key,
306 unsigned int master_key_size);
307
308/*
309 * The list of contexts in which fscrypt uses HKDF. These values are used as
310 * the first byte of the HKDF application-specific info string to guarantee that
311 * info strings are never repeated between contexts. This ensures that all HKDF
312 * outputs are unique and cryptographically isolated, i.e. knowledge of one
313 * output doesn't reveal another.
314 */
315#define HKDF_CONTEXT_KEY_IDENTIFIER 1 /* info=<empty> */
316#define HKDF_CONTEXT_PER_FILE_ENC_KEY 2 /* info=file_nonce */
317#define HKDF_CONTEXT_DIRECT_KEY 3 /* info=mode_num */
318#define HKDF_CONTEXT_IV_INO_LBLK_64_KEY 4 /* info=mode_num||fs_uuid */
319#define HKDF_CONTEXT_DIRHASH_KEY 5 /* info=file_nonce */
320#define HKDF_CONTEXT_IV_INO_LBLK_32_KEY 6 /* info=mode_num||fs_uuid */
321#define HKDF_CONTEXT_INODE_HASH_KEY 7 /* info=<empty> */
322
323int fscrypt_hkdf_expand(const struct fscrypt_hkdf *hkdf, u8 context,
324 const u8 *info, unsigned int infolen,
325 u8 *okm, unsigned int okmlen);
326
327void fscrypt_destroy_hkdf(struct fscrypt_hkdf *hkdf);
328
329/* inline_crypt.c */
330#ifdef CONFIG_FS_ENCRYPTION_INLINE_CRYPT
331int fscrypt_select_encryption_impl(struct fscrypt_info *ci);
332
333static inline bool
334fscrypt_using_inline_encryption(const struct fscrypt_info *ci)
335{
336 return ci->ci_inlinecrypt;
337}
338
339int fscrypt_prepare_inline_crypt_key(struct fscrypt_prepared_key *prep_key,
340 const u8 *raw_key,
341 const struct fscrypt_info *ci);
342
343void fscrypt_destroy_inline_crypt_key(struct fscrypt_prepared_key *prep_key);
344
345/*
346 * Check whether the crypto transform or blk-crypto key has been allocated in
347 * @prep_key, depending on which encryption implementation the file will use.
348 */
349static inline bool
350fscrypt_is_key_prepared(struct fscrypt_prepared_key *prep_key,
351 const struct fscrypt_info *ci)
352{
353 /*
354 * The two smp_load_acquire()'s here pair with the smp_store_release()'s
355 * in fscrypt_prepare_inline_crypt_key() and fscrypt_prepare_key().
356 * I.e., in some cases (namely, if this prep_key is a per-mode
357 * encryption key) another task can publish blk_key or tfm concurrently,
358 * executing a RELEASE barrier. We need to use smp_load_acquire() here
359 * to safely ACQUIRE the memory the other task published.
360 */
361 if (fscrypt_using_inline_encryption(ci))
362 return smp_load_acquire(&prep_key->blk_key) != NULL;
363 return smp_load_acquire(&prep_key->tfm) != NULL;
364}
365
366#else /* CONFIG_FS_ENCRYPTION_INLINE_CRYPT */
367
368static inline int fscrypt_select_encryption_impl(struct fscrypt_info *ci)
369{
370 return 0;
371}
372
373static inline bool
374fscrypt_using_inline_encryption(const struct fscrypt_info *ci)
375{
376 return false;
377}
378
379static inline int
380fscrypt_prepare_inline_crypt_key(struct fscrypt_prepared_key *prep_key,
381 const u8 *raw_key,
382 const struct fscrypt_info *ci)
383{
384 WARN_ON(1);
385 return -EOPNOTSUPP;
386}
387
388static inline void
389fscrypt_destroy_inline_crypt_key(struct fscrypt_prepared_key *prep_key)
390{
391}
392
393static inline bool
394fscrypt_is_key_prepared(struct fscrypt_prepared_key *prep_key,
395 const struct fscrypt_info *ci)
396{
397 return smp_load_acquire(&prep_key->tfm) != NULL;
398}
399#endif /* !CONFIG_FS_ENCRYPTION_INLINE_CRYPT */
400
401/* keyring.c */
402
403/*
404 * fscrypt_master_key_secret - secret key material of an in-use master key
405 */
406struct fscrypt_master_key_secret {
407
408 /*
409 * For v2 policy keys: HKDF context keyed by this master key.
410 * For v1 policy keys: not set (hkdf.hmac_tfm == NULL).
411 */
412 struct fscrypt_hkdf hkdf;
413
414 /* Size of the raw key in bytes. Set even if ->raw isn't set. */
415 u32 size;
416
417 /* For v1 policy keys: the raw key. Wiped for v2 policy keys. */
418 u8 raw[FSCRYPT_MAX_KEY_SIZE];
419
420} __randomize_layout;
421
422/*
423 * fscrypt_master_key - an in-use master key
424 *
425 * This represents a master encryption key which has been added to the
426 * filesystem and can be used to "unlock" the encrypted files which were
427 * encrypted with it.
428 */
429struct fscrypt_master_key {
430
431 /*
432 * The secret key material. After FS_IOC_REMOVE_ENCRYPTION_KEY is
433 * executed, this is wiped and no new inodes can be unlocked with this
434 * key; however, there may still be inodes in ->mk_decrypted_inodes
435 * which could not be evicted. As long as some inodes still remain,
436 * FS_IOC_REMOVE_ENCRYPTION_KEY can be retried, or
437 * FS_IOC_ADD_ENCRYPTION_KEY can add the secret again.
438 *
439 * Locking: protected by key->sem (outer) and mk_secret_sem (inner).
440 * The reason for two locks is that key->sem also protects modifying
441 * mk_users, which ranks it above the semaphore for the keyring key
442 * type, which is in turn above page faults (via keyring_read). But
443 * sometimes filesystems call fscrypt_get_encryption_info() from within
444 * a transaction, which ranks it below page faults. So we need a
445 * separate lock which protects mk_secret but not also mk_users.
446 */
447 struct fscrypt_master_key_secret mk_secret;
448 struct rw_semaphore mk_secret_sem;
449
450 /*
451 * For v1 policy keys: an arbitrary key descriptor which was assigned by
452 * userspace (->descriptor).
453 *
454 * For v2 policy keys: a cryptographic hash of this key (->identifier).
455 */
456 struct fscrypt_key_specifier mk_spec;
457
458 /*
459 * Keyring which contains a key of type 'key_type_fscrypt_user' for each
460 * user who has added this key. Normally each key will be added by just
461 * one user, but it's possible that multiple users share a key, and in
462 * that case we need to keep track of those users so that one user can't
463 * remove the key before the others want it removed too.
464 *
465 * This is NULL for v1 policy keys; those can only be added by root.
466 *
467 * Locking: in addition to this keyrings own semaphore, this is
468 * protected by the master key's key->sem, so we can do atomic
469 * search+insert. It can also be searched without taking any locks, but
470 * in that case the returned key may have already been removed.
471 */
472 struct key *mk_users;
473
474 /*
475 * Length of ->mk_decrypted_inodes, plus one if mk_secret is present.
476 * Once this goes to 0, the master key is removed from ->s_master_keys.
477 * The 'struct fscrypt_master_key' will continue to live as long as the
478 * 'struct key' whose payload it is, but we won't let this reference
479 * count rise again.
480 */
481 refcount_t mk_refcount;
482
483 /*
484 * List of inodes that were unlocked using this key. This allows the
485 * inodes to be evicted efficiently if the key is removed.
486 */
487 struct list_head mk_decrypted_inodes;
488 spinlock_t mk_decrypted_inodes_lock;
489
490 /*
491 * Per-mode encryption keys for the various types of encryption policies
492 * that use them. Allocated and derived on-demand.
493 */
494 struct fscrypt_prepared_key mk_direct_keys[__FSCRYPT_MODE_MAX + 1];
495 struct fscrypt_prepared_key mk_iv_ino_lblk_64_keys[__FSCRYPT_MODE_MAX + 1];
496 struct fscrypt_prepared_key mk_iv_ino_lblk_32_keys[__FSCRYPT_MODE_MAX + 1];
497
498 /* Hash key for inode numbers. Initialized only when needed. */
499 siphash_key_t mk_ino_hash_key;
500 bool mk_ino_hash_key_initialized;
501
502} __randomize_layout;
503
504static inline bool
505is_master_key_secret_present(const struct fscrypt_master_key_secret *secret)
506{
507 /*
508 * The READ_ONCE() is only necessary for fscrypt_drop_inode() and
509 * fscrypt_key_describe(). These run in atomic context, so they can't
510 * take ->mk_secret_sem and thus 'secret' can change concurrently which
511 * would be a data race. But they only need to know whether the secret
512 * *was* present at the time of check, so READ_ONCE() suffices.
513 */
514 return READ_ONCE(secret->size) != 0;
515}
516
517static inline const char *master_key_spec_type(
518 const struct fscrypt_key_specifier *spec)
519{
520 switch (spec->type) {
521 case FSCRYPT_KEY_SPEC_TYPE_DESCRIPTOR:
522 return "descriptor";
523 case FSCRYPT_KEY_SPEC_TYPE_IDENTIFIER:
524 return "identifier";
525 }
526 return "[unknown]";
527}
528
529static inline int master_key_spec_len(const struct fscrypt_key_specifier *spec)
530{
531 switch (spec->type) {
532 case FSCRYPT_KEY_SPEC_TYPE_DESCRIPTOR:
533 return FSCRYPT_KEY_DESCRIPTOR_SIZE;
534 case FSCRYPT_KEY_SPEC_TYPE_IDENTIFIER:
535 return FSCRYPT_KEY_IDENTIFIER_SIZE;
536 }
537 return 0;
538}
539
540struct key *
541fscrypt_find_master_key(struct super_block *sb,
542 const struct fscrypt_key_specifier *mk_spec);
543
544int fscrypt_add_test_dummy_key(struct super_block *sb,
545 struct fscrypt_key_specifier *key_spec);
546
547int fscrypt_verify_key_added(struct super_block *sb,
548 const u8 identifier[FSCRYPT_KEY_IDENTIFIER_SIZE]);
549
550int __init fscrypt_init_keyring(void);
551
552/* keysetup.c */
553
554struct fscrypt_mode {
555 const char *friendly_name;
556 const char *cipher_str;
557 int keysize;
558 int ivsize;
559 int logged_impl_name;
560 enum blk_crypto_mode_num blk_crypto_mode;
561};
562
563extern struct fscrypt_mode fscrypt_modes[];
564
565int fscrypt_prepare_key(struct fscrypt_prepared_key *prep_key,
566 const u8 *raw_key, const struct fscrypt_info *ci);
567
568void fscrypt_destroy_prepared_key(struct fscrypt_prepared_key *prep_key);
569
570int fscrypt_set_per_file_enc_key(struct fscrypt_info *ci, const u8 *raw_key);
571
572int fscrypt_derive_dirhash_key(struct fscrypt_info *ci,
573 const struct fscrypt_master_key *mk);
574
575/* keysetup_v1.c */
576
577void fscrypt_put_direct_key(struct fscrypt_direct_key *dk);
578
579int fscrypt_setup_v1_file_key(struct fscrypt_info *ci,
580 const u8 *raw_master_key);
581
582int fscrypt_setup_v1_file_key_via_subscribed_keyrings(struct fscrypt_info *ci);
583
584/* policy.c */
585
586bool fscrypt_policies_equal(const union fscrypt_policy *policy1,
587 const union fscrypt_policy *policy2);
588bool fscrypt_supported_policy(const union fscrypt_policy *policy_u,
589 const struct inode *inode);
590int fscrypt_policy_from_context(union fscrypt_policy *policy_u,
591 const union fscrypt_context *ctx_u,
592 int ctx_size);
593
594#endif /* _FSCRYPT_PRIVATE_H */