Commit a0fc2033 authored by Ard Biesheuvel's avatar Ard Biesheuvel Committed by Herbert Xu
Browse files

fscrypt: relax Kconfig dependencies for crypto API algorithms 



Even if FS encryption has strict functional dependencies on various
crypto algorithms and chaining modes. those dependencies could potentially
be satisified by other implementations than the generic ones, and no link
time dependency exists on the 'depends on' claused defined by
CONFIG_FS_ENCRYPTION_ALGS.

So let's relax these clauses to 'imply', so that the default behavior
is still to pull in those generic algorithms, but in a way that permits
them to be disabled again in Kconfig.

Signed-off-by: default avatarArd Biesheuvel <ardb@kernel.org>
Acked-by: default avatarEric Biggers <ebiggers@google.com>
Signed-off-by: default avatarHerbert Xu <herbert@gondor.apana.org.au>
parent d17d9227

fs/crypto/Kconfig

+22 −8
Original line number Diff line number Diff line
@@ -14,16 +14,30 @@ config FS_ENCRYPTION 
	  F2FS and UBIFS make use of this feature.



# Filesystems supporting encryption must select this if FS_ENCRYPTION.  This

# allows the algorithms to be built as modules when all the filesystems are.

# allows the algorithms to be built as modules when all the filesystems are,

# whereas selecting them from FS_ENCRYPTION would force them to be built-in.

#

# Note: this option only pulls in the algorithms that filesystem encryption

# needs "by default".  If userspace will use "non-default" encryption modes such

# as Adiantum encryption, then those other modes need to be explicitly enabled

# in the crypto API; see Documentation/filesystems/fscrypt.rst for details.

#

# Also note that this option only pulls in the generic implementations of the

# algorithms, not any per-architecture optimized implementations.  It is

# strongly recommended to enable optimized implementations too.  It is safe to

# disable these generic implementations if corresponding optimized

# implementations will always be available too; for this reason, these are soft

# dependencies ('imply' rather than 'select').  Only disable these generic

# implementations if you're sure they will never be needed, though.

config FS_ENCRYPTION_ALGS

	tristate

	select CRYPTO_AES

	select CRYPTO_CBC

	select CRYPTO_CTS

	select CRYPTO_ECB

	select CRYPTO_HMAC

	select CRYPTO_SHA512

	select CRYPTO_XTS

	imply CRYPTO_AES

	imply CRYPTO_CBC

	imply CRYPTO_CTS

	imply CRYPTO_ECB

	imply CRYPTO_HMAC

	imply CRYPTO_SHA512

	imply CRYPTO_XTS



config FS_ENCRYPTION_INLINE_CRYPT

	bool "Enable fscrypt to use inline crypto"