Checks the linkage of a kext

check-kext-linkage

###########
#  Copies a kext to a temporary location and test loading it (to make sure that all
#  library linkages are in place).  This is a standalone script because in order
#  for a kext to be loaded, it must have ownership of root:wheel - which requires
#  root to change.
#
#  This script will call sudo on itself if it is run as non-root.
#
#  In order to prevent this script for prompting for a password (i.e. for use in
#  continuous integration or for other cases where you are too lazy to type in
#  your password), you can add a file to /etc/sudoers.d by running the following
#  command:
#      > sudo visudo -f /etc/sudoers.d/check-kext-linkage
#
#  And adding the following lines to the file (assuming you install this script
#  to /usr/local/bin/check-kext-linkage):
#      %admin  ALL=(root) NOPASSWD: /usr/local/bin/check-kext-linkage
#      Defaults env_keep += "TMPDIR"
#
#!/bin/bash
[ -d "${1}" ] || {
    echo "Usage: ${0} <path/to/test.kext>" >&2
    exit 1
}

# Make sure we are running as root
if [ "$(id -u)" != "0" ]; then /usr/bin/sudo "${0}" "$@"; exit $?; fi

# Copy to our temporary location - set it to clean up whenever the script exits
TMPKEXT="${TMPDIR:-/tmp}/check-kext.$$.kext"
/bin/cp -r "${1}" "${TMPKEXT}" || exit $?
trap 'rm -rf "${TMPKEXT}"' EXIT

# Change permissions - kext ownership should be root:wheel in order to work
/usr/sbin/chown -R root:wheel "${TMPKEXT}" || exit $?

# Test load the kext - this should fail if we are missing dependencies, or if there is
# something else wrong with the kext
/usr/bin/kextutil -nt "${TMPKEXT}"