/* SPDX-License-Identifier: GPL-2.0 */ /* * fscrypt_private.h * * Copyright (C) 2015, Google, Inc. * * Originally written by Michael Halcrow, Ildar Muslukhov, and Uday Savagaonkar. * Heavily modified since then. */ #ifndef _FSCRYPT_PRIVATE_H #define _FSCRYPT_PRIVATE_H #include <crypto/sha2.h> #include <linux/fscrypt.h> #include <linux/minmax.h> #include <linux/siphash.h> #include <linux/blk-crypto.h> #define CONST_STRLEN(str) (sizeof(str) - 1) #define FSCRYPT_FILE_NONCE_SIZE 16 /* * Minimum size of an fscrypt master key. Note: a longer key will be required * if ciphers with a 256-bit security strength are used. This is just the * absolute minimum, which applies when only 128-bit encryption is used. */ #define FSCRYPT_MIN_KEY_SIZE 16 /* Maximum size of a raw fscrypt master key */ #define FSCRYPT_MAX_RAW_KEY_SIZE 64 /* Maximum size of a hardware-wrapped fscrypt master key */ #define FSCRYPT_MAX_HW_WRAPPED_KEY_SIZE BLK_CRYPTO_MAX_HW_WRAPPED_KEY_SIZE /* Maximum size of an fscrypt master key across both key types */ #define FSCRYPT_MAX_ANY_KEY_SIZE \ MAX(FSCRYPT_MAX_RAW_KEY_SIZE, FSCRYPT_MAX_HW_WRAPPED_KEY_SIZE) /* * FSCRYPT_MAX_KEY_SIZE is defined in the UAPI header, but the addition of * hardware-wrapped keys has made it misleading as it's only for raw keys. * Don't use it in kernel code; use one of the above constants instead. */ #undef FSCRYPT_MAX_KEY_SIZE /* * This mask is passed as the third argument to the crypto_alloc_*() functions * to prevent fscrypt from using the Crypto API drivers for non-inline crypto * engines. Those drivers have been problematic for fscrypt. fscrypt users * have reported hangs and even incorrect en/decryption with these drivers. * Since going to the driver, off CPU, and back again is really slow, such * drivers can be over 50 times slower than the CPU-based code for fscrypt's * workload. Even on platforms that lack AES instructions on the CPU, using the * offloads has been shown to be slower, even staying with AES. (Of course, * Adiantum is faster still, and is the recommended option on such platforms...) * * Note that fscrypt also supports inline crypto engines. Those don't use the * Crypto API and work much better than the old-style (non-inline) engines. */ #define FSCRYPT_CRYPTOAPI_MASK \ (CRYPTO_ALG_ASYNC | CRYPTO_ALG_ALLOCATES_MEMORY | \ CRYPTO_ALG_KERN_DRIVER_ONLY) #define FSCRYPT_CONTEXT_V1 1 #define FSCRYPT_CONTEXT_V2 2 /* Keep this in sync with include/uapi/linux/fscrypt.h */ #define FSCRYPT_MODE_MAX FSCRYPT_MODE_AES_256_HCTR2 struct fscrypt_context_v1 { u8 version; /* FSCRYPT_CONTEXT_V1 */ u8 contents_encryption_mode; u8 filenames_encryption_mode; u8 flags; u8 master_key_descriptor[FSCRYPT_KEY_DESCRIPTOR_SIZE]; u8 nonce[FSCRYPT_FILE_NONCE_SIZE]; }; struct fscrypt_context_v2 { u8 version; /* FSCRYPT_CONTEXT_V2 */ u8 contents_encryption_mode; u8 filenames_encryption_mode; u8 flags; u8 log2_data_unit_size; u8 __reserved[3]; u8 master_key_identifier[FSCRYPT_KEY_IDENTIFIER_SIZE]; u8 nonce[FSCRYPT_FILE_NONCE_SIZE]; }; /* * fscrypt_context - the encryption context of an inode * * This is the on-disk equivalent of an fscrypt_policy, stored alongside each * encrypted file usually in a hidden extended attribute. It contains the * fields from the fscrypt_policy, in order to identify the encryption algorithm * and key with which the file is encrypted. It also contains a nonce that was * randomly generated by fscrypt itself; this is used as KDF input or as a tweak * to cause different files to be encrypted differently. */ union fscrypt_context { u8 version; struct fscrypt_context_v1 v1; struct fscrypt_context_v2 v2; }; /* * Return the size expected for the given fscrypt_context based on its version * number, or 0 if the context version is unrecognized. */ static inline int fscrypt_context_size(const union fscrypt_context *ctx) { switch (ctx->version) { case FSCRYPT_CONTEXT_V1: BUILD_BUG_ON(sizeof(ctx->v1) != 28); return sizeof(ctx->v1); case FSCRYPT_CONTEXT_V2: BUILD_BUG_ON(sizeof(ctx->v2) != 40); return sizeof(ctx->v2); } return 0; } /* Check whether an fscrypt_context has a recognized version number and size */ static inline bool fscrypt_context_is_valid(const union fscrypt_context *ctx, int ctx_size) { return ctx_size >= 1 && ctx_size == fscrypt_context_size(ctx); } /* Retrieve the context's nonce, assuming the context was already validated */ static inline const u8 *fscrypt_context_nonce(const union fscrypt_context *ctx) { switch (ctx->version) { case FSCRYPT_CONTEXT_V1: return ctx->v1.nonce; case FSCRYPT_CONTEXT_V2: return ctx->v2.nonce; } WARN_ON_ONCE(1); return NULL; } union fscrypt_policy { u8 version; struct fscrypt_policy_v1 v1; struct fscrypt_policy_v2 v2; }; /* * Return the size expected for the given fscrypt_policy based on its version * number, or 0 if the policy version is unrecognized. */ static inline int fscrypt_policy_size(const union fscrypt_policy *policy) { switch (policy->version) { case FSCRYPT_POLICY_V1: return sizeof(policy->v1); case FSCRYPT_POLICY_V2: return sizeof(policy->v2); } return 0; } /* Return the contents encryption mode of a valid encryption policy */ static inline u8 fscrypt_policy_contents_mode(const union fscrypt_policy *policy) { switch (policy->version) { case FSCRYPT_POLICY_V1: return policy->v1.contents_encryption_mode; case FSCRYPT_POLICY_V2: return policy->v2.contents_encryption_mode; } BUG(); } /* Return the filenames encryption mode of a valid encryption policy */ static inline u8 fscrypt_policy_fnames_mode(const union fscrypt_policy *policy) { switch (policy->version) { case FSCRYPT_POLICY_V1: return policy->v1.filenames_encryption_mode; case FSCRYPT_POLICY_V2: return policy->v2.filenames_encryption_mode; } BUG(); } /* Return the flags (FSCRYPT_POLICY_FLAG*) of a valid encryption policy */ static inline u8 fscrypt_policy_flags(const union fscrypt_policy *policy) { switch (policy->version) { case FSCRYPT_POLICY_V1: return policy->v1.flags; case FSCRYPT_POLICY_V2: return policy->v2.flags; } BUG(); } static inline int fscrypt_policy_v2_du_bits(const struct fscrypt_policy_v2 *policy, const struct inode *inode) { return policy->log2_data_unit_size ?: inode->i_blkbits; } static inline int fscrypt_policy_du_bits(const union fscrypt_policy *policy, const struct inode *inode) { switch (policy->version) { case FSCRYPT_POLICY_V1: return inode->i_blkbits; case FSCRYPT_POLICY_V2: return fscrypt_policy_v2_du_bits(&policy->v2, inode); } BUG(); } /* * For encrypted symlinks, the ciphertext length is stored at the beginning * of the string in little-endian format. */ struct fscrypt_symlink_data { __le16 len; char encrypted_path[]; } __packed; /** * struct fscrypt_prepared_key - a key prepared for actual encryption/decryption * @tfm: crypto API transform object * @blk_key: key for blk-crypto * * Normally only one of the fields will be non-NULL. */ struct fscrypt_prepared_key { struct crypto_sync_skcipher *tfm; #ifdef CONFIG_FS_ENCRYPTION_INLINE_CRYPT struct blk_crypto_key *blk_key; #endif }; /* * fscrypt_inode_info - the "encryption key" for an inode * * When an encrypted file's key is made available, an instance of this struct is * allocated and a pointer to it is stored in the file's in-memory inode. Once * created, it remains until the inode is evicted. */ struct fscrypt_inode_info { /* The key in a form prepared for actual encryption/decryption */ struct fscrypt_prepared_key ci_enc_key; /* True if ci_enc_key should be freed when this struct is freed */ u8 ci_owns_key : 1; #ifdef CONFIG_FS_ENCRYPTION_INLINE_CRYPT /* * True if this inode will use inline encryption (blk-crypto) instead of * the traditional filesystem-layer encryption. */ u8 ci_inlinecrypt : 1; #endif /* True if ci_dirhash_key is initialized */ u8 ci_dirhash_key_initialized : 1; /* * log2 of the data unit size (granularity of contents encryption) of * this file. This is computable from ci_policy and ci_inode but is * cached here for efficiency. Only used for regular files. */ u8 ci_data_unit_bits; /* Cached value: log2 of number of data units per FS block */ u8 ci_data_units_per_block_bits; /* Hashed inode number. Only set for IV_INO_LBLK_32 */ u32 ci_hashed_ino; /* * Encryption mode used for this inode. It corresponds to either the * contents or filenames encryption mode, depending on the inode type. */ struct fscrypt_mode *ci_mode; /* Back-pointer to the inode */ struct inode *ci_inode; /* * The master key with which this inode was unlocked (decrypted). This * will be NULL if the master key was found in a process-subscribed * keyring rather than in the filesystem-level keyring. */ struct fscrypt_master_key *ci_master_key; /* * Link in list of inodes that were unlocked with the master key. * Only used when ->ci_master_key is set. */ struct list_head ci_master_key_link; /* * If non-NULL, then encryption is done using the master key directly * and ci_enc_key will equal ci_direct_key->dk_key. */ struct fscrypt_direct_key *ci_direct_key; /* * This inode's hash key for filenames. This is a 128-bit SipHash-2-4 * key. This is only set for directories that use a keyed dirhash over * the plaintext filenames -- currently just casefolded directories. */ siphash_key_t ci_dirhash_key; /* The encryption policy used by this inode */ union fscrypt_policy ci_policy; /* This inode's nonce, copied from the fscrypt_context */ u8 ci_nonce[FSCRYPT_FILE_NONCE_SIZE]; }; typedef enum { FS_DECRYPT = 0, FS_ENCRYPT, } fscrypt_direction_t; /* crypto.c */ extern struct kmem_cache *fscrypt_inode_info_cachep; int fscrypt_initialize(struct super_block *sb); int fscrypt_crypt_data_unit(const struct fscrypt_inode_info *ci, fscrypt_direction_t rw, u64 index, struct page *src_page, struct page *dest_page, unsigned int len, unsigned int offs); struct page *fscrypt_alloc_bounce_page(gfp_t gfp_flags); void __printf(3, 4) __cold fscrypt_msg(const struct inode *inode, const char *level, const char *fmt, ...); #define fscrypt_warn(inode, fmt, ...) \ fscrypt_msg((inode), KERN_WARNING, fmt, ##__VA_ARGS__) #define fscrypt_err(inode, fmt, ...) \ fscrypt_msg((inode), KERN_ERR, fmt, ##__VA_ARGS__) #define FSCRYPT_MAX_IV_SIZE 32 union fscrypt_iv { struct { /* zero-based index of data unit within the file */ __le64 index; /* per-file nonce; only set in DIRECT_KEY mode */ u8 nonce[FSCRYPT_FILE_NONCE_SIZE]; }; u8 raw[FSCRYPT_MAX_IV_SIZE]; __le64 dun[FSCRYPT_MAX_IV_SIZE / sizeof(__le64)]; }; void fscrypt_generate_iv(union fscrypt_iv *iv, u64 index, const struct fscrypt_inode_info *ci); /* * Return the number of bits used by the maximum file data unit index that is * possible on the given filesystem, using the given log2 data unit size. */ static inline int fscrypt_max_file_dun_bits(const struct super_block *sb, int du_bits) { return fls64(sb->s_maxbytes - 1) - du_bits; } /* fname.c */ bool __fscrypt_fname_encrypted_size(const union fscrypt_policy *policy, u32 orig_len, u32 max_len, u32 *encrypted_len_ret); /* hkdf.c */ void fscrypt_init_hkdf(struct hmac_sha512_key *hkdf, const u8 *master_key, unsigned int master_key_size); /* * The list of contexts in which fscrypt uses HKDF. These values are used as * the first byte of the HKDF application-specific info string to guarantee that * info strings are never repeated between contexts. This ensures that all HKDF * outputs are unique and cryptographically isolated, i.e. knowledge of one * output doesn't reveal another. */ #define HKDF_CONTEXT_KEY_IDENTIFIER_FOR_RAW_KEY 1 /* info=<empty> */ #define HKDF_CONTEXT_PER_FILE_ENC_KEY 2 /* info=file_nonce */ #define HKDF_CONTEXT_DIRECT_KEY 3 /* info=mode_num */ #define HKDF_CONTEXT_IV_INO_LBLK_64_KEY 4 /* info=mode_num||fs_uuid */ #define HKDF_CONTEXT_DIRHASH_KEY 5 /* info=file_nonce */ #define HKDF_CONTEXT_IV_INO_LBLK_32_KEY 6 /* info=mode_num||fs_uuid */ #define HKDF_CONTEXT_INODE_HASH_KEY 7 /* info=<empty> */ #define HKDF_CONTEXT_KEY_IDENTIFIER_FOR_HW_WRAPPED_KEY \ 8 /* info=<empty> */ void fscrypt_hkdf_expand(const struct hmac_sha512_key *hkdf, u8 context, const u8 *info, unsigned int infolen, u8 *okm, unsigned int okmlen); /* inline_crypt.c */ #ifdef CONFIG_FS_ENCRYPTION_INLINE_CRYPT int fscrypt_select_encryption_impl(struct fscrypt_inode_info *ci, bool is_hw_wrapped_key); static inline bool fscrypt_using_inline_encryption(const struct fscrypt_inode_info *ci) { return ci->ci_inlinecrypt; } int fscrypt_prepare_inline_crypt_key(struct fscrypt_prepared_key *prep_key, const u8 *key_bytes, size_t key_size, bool is_hw_wrapped, const struct fscrypt_inode_info *ci); void fscrypt_destroy_inline_crypt_key(struct super_block *sb, struct fscrypt_prepared_key *prep_key); int fscrypt_derive_sw_secret(struct super_block *sb, const u8 *wrapped_key, size_t wrapped_key_size, u8 sw_secret[BLK_CRYPTO_SW_SECRET_SIZE]); /* * Check whether the crypto transform or blk-crypto key has been allocated in * @prep_key, depending on which encryption implementation the file will use. */ static inline bool fscrypt_is_key_prepared(struct fscrypt_prepared_key *prep_key, const struct fscrypt_inode_info *ci) { /* * The two smp_load_acquire()'s here pair with the smp_store_release()'s * in fscrypt_prepare_inline_crypt_key() and fscrypt_prepare_key(). * I.e., in some cases (namely, if this prep_key is a per-mode * encryption key) another task can publish blk_key or tfm concurrently, * executing a RELEASE barrier. We need to use smp_load_acquire() here * to safely ACQUIRE the memory the other task published. */ if (fscrypt_using_inline_encryption(ci)) return smp_load_acquire(&prep_key->blk_key) != NULL; return smp_load_acquire(&prep_key->tfm) != NULL; } #else /* CONFIG_FS_ENCRYPTION_INLINE_CRYPT */ static inline int fscrypt_select_encryption_impl(struct fscrypt_inode_info *ci, bool is_hw_wrapped_key) { return 0; } static inline bool fscrypt_using_inline_encryption(const struct fscrypt_inode_info *ci) { return false; } static inline int fscrypt_prepare_inline_crypt_key(struct fscrypt_prepared_key *prep_key, const u8 *key_bytes, size_t key_size, bool is_hw_wrapped, const struct fscrypt_inode_info *ci) { WARN_ON_ONCE(1); return -EOPNOTSUPP; } static inline void fscrypt_destroy_inline_crypt_key(struct super_block *sb, struct fscrypt_prepared_key *prep_key) { } static inline int fscrypt_derive_sw_secret(struct super_block *sb, const u8 *wrapped_key, size_t wrapped_key_size, u8 sw_secret[BLK_CRYPTO_SW_SECRET_SIZE]) { fscrypt_warn(NULL, "kernel doesn't support hardware-wrapped keys"); return -EOPNOTSUPP; } static inline bool fscrypt_is_key_prepared(struct fscrypt_prepared_key *prep_key, const struct fscrypt_inode_info *ci) { return smp_load_acquire(&prep_key->tfm) != NULL; } #endif /* !CONFIG_FS_ENCRYPTION_INLINE_CRYPT */ /* keyring.c */ /* * fscrypt_master_key_secret - secret key material of an in-use master key */ struct fscrypt_master_key_secret { /* * The KDF with which subkeys of this key can be derived. * * For v1 policy keys, this isn't applicable and won't be set. * Otherwise, this KDF will be keyed by this master key if * ->is_hw_wrapped=false, or by the "software secret" that hardware * derived from this master key if ->is_hw_wrapped=true. */ struct hmac_sha512_key hkdf; /* * True if this key is a hardware-wrapped key; false if this key is a * raw key (i.e. a "software key"). For v1 policy keys this will always * be false, as v1 policy support is a legacy feature which doesn't * support newer functionality such as hardware-wrapped keys. */ bool is_hw_wrapped; /* * Size of the key in bytes. This remains set even if ->bytes was * zeroized due to no longer being needed. I.e. we still remember the * size of the key even if we don't need to remember the key itself. */ u32 size; /* * The bytes of the key, when still needed. This can be either a raw * key or a hardware-wrapped key, as indicated by ->is_hw_wrapped. In * the case of a raw, v2 policy key, there is no need to remember the * actual key separately from ->hkdf so this field will be zeroized as * soon as ->hkdf is initialized. */ u8 bytes[FSCRYPT_MAX_ANY_KEY_SIZE]; } __randomize_layout; /* * fscrypt_master_key - an in-use master key * * This represents a master encryption key which has been added to the * filesystem. There are three high-level states that a key can be in: * * FSCRYPT_KEY_STATUS_PRESENT * Key is fully usable; it can be used to unlock inodes that are encrypted * with it (this includes being able to create new inodes). ->mk_present * indicates whether the key is in this state. ->mk_secret exists, the key * is in the keyring, and ->mk_active_refs > 0 due to ->mk_present. * * FSCRYPT_KEY_STATUS_INCOMPLETELY_REMOVED * Removal of this key has been initiated, but some inodes that were * unlocked with it are still in-use. Like ABSENT, ->mk_secret is wiped, * and the key can no longer be used to unlock inodes. Unlike ABSENT, the * key is still in the keyring; ->mk_decrypted_inodes is nonempty; and * ->mk_active_refs > 0, being equal to the size of ->mk_decrypted_inodes. * * This state transitions to ABSENT if ->mk_decrypted_inodes becomes empty, * or to PRESENT if FS_IOC_ADD_ENCRYPTION_KEY is called again for this key. * * FSCRYPT_KEY_STATUS_ABSENT * Key is fully removed. The key is no longer in the keyring, * ->mk_decrypted_inodes is empty, ->mk_active_refs == 0, ->mk_secret is * wiped, and the key can no longer be used to unlock inodes. */ struct fscrypt_master_key { /* * Link in ->s_master_keys->key_hashtable. * Only valid if ->mk_active_refs > 0. */ struct hlist_node mk_node; /* Semaphore that protects ->mk_secret, ->mk_users, and ->mk_present */ struct rw_semaphore mk_sem; /* * Active and structural reference counts. An active ref guarantees * that the struct continues to exist, continues to be in the keyring * ->s_master_keys, and that any embedded subkeys (e.g. * ->mk_direct_keys) that have been prepared continue to exist. * A structural ref only guarantees that the struct continues to exist. * * There is one active ref associated with ->mk_present being true, and * one active ref for each inode in ->mk_decrypted_inodes. * * There is one structural ref associated with the active refcount being * nonzero. Finding a key in the keyring also takes a structural ref, * which is then held temporarily while the key is operated on. */ refcount_t mk_active_refs; refcount_t mk_struct_refs; struct rcu_head mk_rcu_head; /* * The secret key material. Wiped as soon as it is no longer needed; * for details, see the fscrypt_master_key struct comment. * * Locking: protected by ->mk_sem. */ struct fscrypt_master_key_secret mk_secret; /* * For v1 policy keys: an arbitrary key descriptor which was assigned by * userspace (->descriptor). * * For v2 policy keys: a cryptographic hash of this key (->identifier). */ struct fscrypt_key_specifier mk_spec; /* * Keyring which contains a key of type 'key_type_fscrypt_user' for each * user who has added this key. Normally each key will be added by just * one user, but it's possible that multiple users share a key, and in * that case we need to keep track of those users so that one user can't * remove the key before the others want it removed too. * * This is NULL for v1 policy keys; those can only be added by root. * * Locking: protected by ->mk_sem. (We don't just rely on the keyrings * subsystem semaphore ->mk_users->sem, as we need support for atomic * search+insert along with proper synchronization with other fields.) */ struct key *mk_users; /* * List of inodes that were unlocked using this key. This allows the * inodes to be evicted efficiently if the key is removed. */ struct list_head mk_decrypted_inodes; spinlock_t mk_decrypted_inodes_lock; /* * Per-mode encryption keys for the various types of encryption policies * that use them. Allocated and derived on-demand. */ struct fscrypt_prepared_key mk_direct_keys[FSCRYPT_MODE_MAX + 1]; struct fscrypt_prepared_key mk_iv_ino_lblk_64_keys[FSCRYPT_MODE_MAX + 1]; struct fscrypt_prepared_key mk_iv_ino_lblk_32_keys[FSCRYPT_MODE_MAX + 1]; /* Hash key for inode numbers. Initialized only when needed. */ siphash_key_t mk_ino_hash_key; bool mk_ino_hash_key_initialized; /* * Whether this key is in the "present" state, i.e. fully usable. For * details, see the fscrypt_master_key struct comment. * * Locking: protected by ->mk_sem, but can be read locklessly using * READ_ONCE(). Writers must use WRITE_ONCE() when concurrent readers * are possible. */ bool mk_present; } __randomize_layout; static inline const char *master_key_spec_type( const struct fscrypt_key_specifier *spec) { switch (spec->type) { case FSCRYPT_KEY_SPEC_TYPE_DESCRIPTOR: return "descriptor"; case FSCRYPT_KEY_SPEC_TYPE_IDENTIFIER: return "identifier"; } return "[unknown]"; } static inline int master_key_spec_len(const struct fscrypt_key_specifier *spec) { switch (spec->type) { case FSCRYPT_KEY_SPEC_TYPE_DESCRIPTOR: return FSCRYPT_KEY_DESCRIPTOR_SIZE; case FSCRYPT_KEY_SPEC_TYPE_IDENTIFIER: return FSCRYPT_KEY_IDENTIFIER_SIZE; } return 0; } void fscrypt_put_master_key(struct fscrypt_master_key *mk); void fscrypt_put_master_key_activeref(struct super_block *sb, struct fscrypt_master_key *mk); struct fscrypt_master_key * fscrypt_find_master_key(struct super_block *sb, const struct fscrypt_key_specifier *mk_spec); void fscrypt_get_test_dummy_key_identifier( u8 key_identifier[FSCRYPT_KEY_IDENTIFIER_SIZE]); int fscrypt_add_test_dummy_key(struct super_block *sb, struct fscrypt_key_specifier *key_spec); int fscrypt_verify_key_added(struct super_block *sb, const u8 identifier[FSCRYPT_KEY_IDENTIFIER_SIZE]); int __init fscrypt_init_keyring(void); /* keysetup.c */ struct fscrypt_mode { const char *friendly_name; const char *cipher_str; int keysize; /* key size in bytes */ int security_strength; /* security strength in bytes */ int ivsize; /* IV size in bytes */ int logged_cryptoapi_impl; int logged_blk_crypto_native; int logged_blk_crypto_fallback; enum blk_crypto_mode_num blk_crypto_mode; }; extern struct fscrypt_mode fscrypt_modes[]; int fscrypt_prepare_key(struct fscrypt_prepared_key *prep_key, const u8 *raw_key, const struct fscrypt_inode_info *ci); void fscrypt_destroy_prepared_key(struct super_block *sb, struct fscrypt_prepared_key *prep_key); int fscrypt_set_per_file_enc_key(struct fscrypt_inode_info *ci, const u8 *raw_key); void fscrypt_derive_dirhash_key(struct fscrypt_inode_info *ci, const struct fscrypt_master_key *mk); void fscrypt_hash_inode_number(struct fscrypt_inode_info *ci, const struct fscrypt_master_key *mk); int fscrypt_get_encryption_info(struct inode *inode, bool allow_unsupported); /** * fscrypt_require_key() - require an inode's encryption key * @inode: the inode we need the key for * * If the inode is encrypted, set up its encryption key if not already done. * Then require that the key be present and return -ENOKEY otherwise. * * No locks are needed, and the key will live as long as the struct inode --- so * it won't go away from under you. * * Return: 0 on success, -ENOKEY if the key is missing, or another -errno code * if a problem occurred while setting up the encryption key. */ static inline int fscrypt_require_key(struct inode *inode) { if (IS_ENCRYPTED(inode)) { int err = fscrypt_get_encryption_info(inode, false); if (err) return err; if (!fscrypt_has_encryption_key(inode)) return -ENOKEY; } return 0; } /* keysetup_v1.c */ void fscrypt_put_direct_key(struct fscrypt_direct_key *dk); int fscrypt_setup_v1_file_key(struct fscrypt_inode_info *ci, const u8 *raw_master_key); int fscrypt_setup_v1_file_key_via_subscribed_keyrings( struct fscrypt_inode_info *ci); /* policy.c */ bool fscrypt_policies_equal(const union fscrypt_policy *policy1, const union fscrypt_policy *policy2); int fscrypt_policy_to_key_spec(const union fscrypt_policy *policy, struct fscrypt_key_specifier *key_spec); const union fscrypt_policy *fscrypt_get_dummy_policy(struct super_block *sb); bool fscrypt_supported_policy(const union fscrypt_policy *policy_u, const struct inode *inode); int fscrypt_policy_from_context(union fscrypt_policy *policy_u, const union fscrypt_context *ctx_u, int ctx_size); const union fscrypt_policy *fscrypt_policy_to_inherit(struct inode *dir); #endif /* _FSCRYPT_PRIVATE_H */
