From: Eric Biggers <[email protected]> Add a helper function which checks if an inode is encrypted, and if so, tries to set up its encryption key. This is a pattern which is duplicated in multiple places in each of ext4, f2fs, and ubifs --- for example, when a regular file is asked to be opened or truncated.
Signed-off-by: Eric Biggers <[email protected]> --- include/linux/fscrypt_notsupp.h | 8 ++++++++ include/linux/fscrypt_supp.h | 28 ++++++++++++++++++++++++++++ 2 files changed, 36 insertions(+) diff --git a/include/linux/fscrypt_notsupp.h b/include/linux/fscrypt_notsupp.h index 3f1325ec4646..3cfc953fef71 100644 --- a/include/linux/fscrypt_notsupp.h +++ b/include/linux/fscrypt_notsupp.h @@ -174,4 +174,12 @@ static inline int fscrypt_zeroout_range(const struct inode *inode, pgoff_t lblk, return -EOPNOTSUPP; } +/* hooks.c */ +static inline int fscrypt_require_key(struct inode *inode) +{ + if (IS_ENCRYPTED(inode)) + return -EOPNOTSUPP; + return 0; +} + #endif /* _LINUX_FSCRYPT_NOTSUPP_H */ diff --git a/include/linux/fscrypt_supp.h b/include/linux/fscrypt_supp.h index 32e2fcf13b01..b6d4b5d303a3 100644 --- a/include/linux/fscrypt_supp.h +++ b/include/linux/fscrypt_supp.h @@ -142,4 +142,32 @@ extern void fscrypt_pullback_bio_page(struct page **, bool); extern int fscrypt_zeroout_range(const struct inode *, pgoff_t, sector_t, unsigned int); +/* hooks.c */ + +/** + * 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 currently 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); + + if (err) + return err; + if (!fscrypt_has_encryption_key(inode)) + return -ENOKEY; + } + return 0; +} + #endif /* _LINUX_FSCRYPT_SUPP_H */ -- 2.14.1.821.g8fa685d3b7-goog ------------------------------------------------------------------------------ Check out the vibrant tech community on one of the world's most engaging tech sites, Slashdot.org! http://sdm.link/slashdot _______________________________________________ Linux-f2fs-devel mailing list [email protected] https://lists.sourceforge.net/lists/listinfo/linux-f2fs-devel
