diff options
Diffstat (limited to 'crypto/Kconfig')
| -rw-r--r-- | crypto/Kconfig | 28 |
1 files changed, 28 insertions, 0 deletions
diff --git a/crypto/Kconfig b/crypto/Kconfig index ad86463de715..9e524044d312 100644 --- a/crypto/Kconfig +++ b/crypto/Kconfig @@ -487,6 +487,34 @@ config CRYPTO_ADIANTUM If unsure, say N. +config CRYPTO_ESSIV + tristate "ESSIV support for block encryption" + select CRYPTO_AUTHENC + help + Encrypted salt-sector initialization vector (ESSIV) is an IV + generation method that is used in some cases by fscrypt and/or + dm-crypt. It uses the hash of the block encryption key as the + symmetric key for a block encryption pass applied to the input + IV, making low entropy IV sources more suitable for block + encryption. + + This driver implements a crypto API template that can be + instantiated either as a skcipher or as a aead (depending on the + type of the first template argument), and which defers encryption + and decryption requests to the encapsulated cipher after applying + ESSIV to the input IV. Note that in the aead case, it is assumed + that the keys are presented in the same format used by the authenc + template, and that the IV appears at the end of the authenticated + associated data (AAD) region (which is how dm-crypt uses it.) + + Note that the use of ESSIV is not recommended for new deployments, + and so this only needs to be enabled when interoperability with + existing encrypted volumes of filesystems is required, or when + building for a particular system that requires it (e.g., when + the SoC in question has accelerated CBC but not XTS, making CBC + combined with ESSIV the only feasible mode for h/w accelerated + block encryption) + comment "Hash modes" config CRYPTO_CMAC |