fs crypto: move per-file encryption from f2fs tree to fs/crypto
This patch adds the renamed functions moved from the f2fs crypto files.
1. definitions for per-file encryption used by ext4 and f2fs.
2. crypto.c for encrypt/decrypt functions
a. IO preparation:
- fscrypt_get_ctx / fscrypt_release_ctx
b. before IOs:
- fscrypt_encrypt_page
- fscrypt_decrypt_page
- fscrypt_zeroout_range
c. after IOs:
- fscrypt_decrypt_bio_pages
- fscrypt_pullback_bio_page
- fscrypt_restore_control_page
3. policy.c supporting context management.
a. For ioctls:
- fscrypt_process_policy
- fscrypt_get_policy
b. For context permission
- fscrypt_has_permitted_context
- fscrypt_inherit_context
4. keyinfo.c to handle permissions
- fscrypt_get_encryption_info
- fscrypt_free_encryption_info
5. fname.c to support filename encryption
a. general wrapper functions
- fscrypt_fname_disk_to_usr
- fscrypt_fname_usr_to_disk
- fscrypt_setup_filename
- fscrypt_free_filename
b. specific filename handling functions
- fscrypt_fname_alloc_buffer
- fscrypt_fname_free_buffer
6. Makefile and Kconfig
Cc: Al Viro <viro@ftp.linux.org.uk>
Signed-off-by: Michael Halcrow <mhalcrow@google.com>
Signed-off-by: Ildar Muslukhov <ildarm@google.com>
Signed-off-by: Uday Savagaonkar <savagaon@google.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
diff --git a/fs/crypto/Kconfig b/fs/crypto/Kconfig
new file mode 100644
index 0000000..92348fa
--- /dev/null
+++ b/fs/crypto/Kconfig
@@ -0,0 +1,18 @@
+config FS_ENCRYPTION
+ tristate "FS Encryption (Per-file encryption)"
+ depends on BLOCK
+ select CRYPTO
+ select CRYPTO_AES
+ select CRYPTO_CBC
+ select CRYPTO_ECB
+ select CRYPTO_XTS
+ select CRYPTO_CTS
+ select CRYPTO_CTR
+ select CRYPTO_SHA256
+ select KEYS
+ select ENCRYPTED_KEYS
+ help
+ Enable encryption of files and directories. This
+ feature is similar to ecryptfs, but it is more memory
+ efficient since it avoids caching the encrypted and
+ decrypted pages in the page cache.