From ddbb41148724367394d0880c516bfaeed127b52e Mon Sep 17 00:00:00 2001 From: Mat Martineau Date: Tue, 12 Apr 2016 19:54:58 +0100 Subject: KEYS: Add KEYCTL_DH_COMPUTE command This adds userspace access to Diffie-Hellman computations through a new keyctl() syscall command to calculate shared secrets or public keys using input parameters stored in the keyring. Input key ids are provided in a struct due to the current 5-arg limit for the keyctl syscall. Only user keys are supported in order to avoid exposing the content of logon or encrypted keys. The output is written to the provided buffer, based on the assumption that the values are only needed in userspace. Future support for other types of key derivation would involve a new command, like KEYCTL_ECDH_COMPUTE. Once Diffie-Hellman support is included in the crypto API, this code can be converted to use the crypto API to take advantage of possible hardware acceleration and reduce redundant code. Signed-off-by: Mat Martineau Signed-off-by: David Howells --- security/keys/Kconfig | 11 +++++++++++ 1 file changed, 11 insertions(+) (limited to 'security/keys/Kconfig') diff --git a/security/keys/Kconfig b/security/keys/Kconfig index 45828095080d..f826e8739023 100644 --- a/security/keys/Kconfig +++ b/security/keys/Kconfig @@ -85,3 +85,14 @@ config ENCRYPTED_KEYS Userspace only ever sees/stores encrypted blobs. If you are unsure as to whether this is required, answer N. + +config KEY_DH_OPERATIONS + bool "Diffie-Hellman operations on retained keys" + depends on KEYS + select MPILIB + help + This option provides support for calculating Diffie-Hellman + public keys and shared secrets using values stored as keys + in the kernel. + + If you are unsure as to whether this is required, answer N. -- cgit v1.2.3-59-g8ed1b