• Mat Martineau's avatar
    KEYS: Add KEYCTL_DH_COMPUTE command · ddbb4114
    Mat Martineau authored
    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: default avatarMat Martineau <mathew.j.martineau@linux.intel.com>
    Signed-off-by: default avatarDavid Howells <dhowells@redhat.com>
    ddbb4114
keyctl.c 41.3 KB