diff options
| -rw-r--r-- | fs/crypto/hooks.c | 18 | ||||
| -rw-r--r-- | include/linux/fscrypt.h | 28 | ||||
| -rw-r--r-- | include/linux/fscrypt_notsupp.h | 6 | ||||
| -rw-r--r-- | include/linux/fscrypt_supp.h | 1 |
4 files changed, 53 insertions, 0 deletions
diff --git a/fs/crypto/hooks.c b/fs/crypto/hooks.c index 822cb78f9b45..9f5fb2eb9cf7 100644 --- a/fs/crypto/hooks.c +++ b/fs/crypto/hooks.c @@ -92,3 +92,21 @@ int __fscrypt_prepare_rename(struct inode *old_dir, struct dentry *old_dentry, return 0; } EXPORT_SYMBOL_GPL(__fscrypt_prepare_rename); + +int __fscrypt_prepare_lookup(struct inode *dir, struct dentry *dentry) +{ + int err = fscrypt_get_encryption_info(dir); + + if (err) + return err; + + if (fscrypt_has_encryption_key(dir)) { + spin_lock(&dentry->d_lock); + dentry->d_flags |= DCACHE_ENCRYPTED_WITH_KEY; + spin_unlock(&dentry->d_lock); + } + + d_set_d_op(dentry, &fscrypt_d_ops); + return 0; +} +EXPORT_SYMBOL_GPL(__fscrypt_prepare_lookup); diff --git a/include/linux/fscrypt.h b/include/linux/fscrypt.h index c422367baed9..2327859c8cd2 100644 --- a/include/linux/fscrypt.h +++ b/include/linux/fscrypt.h @@ -237,4 +237,32 @@ static inline int fscrypt_prepare_rename(struct inode *old_dir, return 0; } +/** + * fscrypt_prepare_lookup - prepare to lookup a name in a possibly-encrypted directory + * @dir: directory being searched + * @dentry: filename being looked up + * @flags: lookup flags + * + * Prepare for ->lookup() in a directory which may be encrypted. Lookups can be + * done with or without the directory's encryption key; without the key, + * filenames are presented in encrypted form. Therefore, we'll try to set up + * the directory's encryption key, but even without it the lookup can continue. + * + * To allow invalidating stale dentries if the directory's encryption key is + * added later, we also install a custom ->d_revalidate() method and use the + * DCACHE_ENCRYPTED_WITH_KEY flag to indicate whether a given dentry is a + * plaintext name (flag set) or a ciphertext name (flag cleared). + * + * Return: 0 on success, -errno if a problem occurred while setting up the + * encryption key + */ +static inline int fscrypt_prepare_lookup(struct inode *dir, + struct dentry *dentry, + unsigned int flags) +{ + if (IS_ENCRYPTED(dir)) + return __fscrypt_prepare_lookup(dir, dentry); + return 0; +} + #endif /* _LINUX_FSCRYPT_H */ diff --git a/include/linux/fscrypt_notsupp.h b/include/linux/fscrypt_notsupp.h index 6af378d8126e..c4c6bf2c390e 100644 --- a/include/linux/fscrypt_notsupp.h +++ b/include/linux/fscrypt_notsupp.h @@ -201,4 +201,10 @@ static inline int __fscrypt_prepare_rename(struct inode *old_dir, return -EOPNOTSUPP; } +static inline int __fscrypt_prepare_lookup(struct inode *dir, + struct dentry *dentry) +{ + return -EOPNOTSUPP; +} + #endif /* _LINUX_FSCRYPT_NOTSUPP_H */ diff --git a/include/linux/fscrypt_supp.h b/include/linux/fscrypt_supp.h index 40f35073145f..2db5e9706f60 100644 --- a/include/linux/fscrypt_supp.h +++ b/include/linux/fscrypt_supp.h @@ -151,5 +151,6 @@ extern int __fscrypt_prepare_rename(struct inode *old_dir, struct inode *new_dir, struct dentry *new_dentry, unsigned int flags); +extern int __fscrypt_prepare_lookup(struct inode *dir, struct dentry *dentry); #endif /* _LINUX_FSCRYPT_SUPP_H */ |