xref: /OK3568_Linux_fs/yocto/poky/meta/classes/rootfsdebugfiles.bbclass (revision 4882a59341e53eb6f0b4789bf948001014eff981)
1# This class installs additional files found on the build host
2# directly into the rootfs.
3#
4# One use case is to install a constant ssh host key in
5# an image that gets created for just one machine. This
6# solves two issues:
7# - host key generation on the device can stall when the
8#   kernel has not gathered enough entropy yet (seen in practice
9#   under qemu)
10# - ssh complains by default when the host key changes
11#
12# For dropbear, with the ssh host key store along side the local.conf:
13# 1. Extend local.conf:
14#    INHERIT += "rootfsdebugfiles"
15#    ROOTFS_DEBUG_FILES += "${TOPDIR}/conf/dropbear_rsa_host_key ${IMAGE_ROOTFS}/etc/dropbear/dropbear_rsa_host_key ;"
16# 2. Boot the image once, copy the dropbear_rsa_host_key from
17#    the device into your build conf directory.
18# 3. A optional parameter can be used to set file mode
19#    of the copied target, for instance:
20#    ROOTFS_DEBUG_FILES += "${TOPDIR}/conf/dropbear_rsa_host_key ${IMAGE_ROOTFS}/etc/dropbear/dropbear_rsa_host_key 0600;"
21#    in case they might be required to have a specific mode. (Shoundn't be too open, for example)
22#
23# Do not use for production images! It bypasses several
24# core build mechanisms (updating the image when one
25# of the files changes, license tracking in the image
26# manifest, ...).
27
28ROOTFS_DEBUG_FILES ?= ""
29ROOTFS_DEBUG_FILES[doc] = "Lists additional files or directories to be installed with 'cp -a' in the format 'source1 target1;source2 target2;...'"
30
31ROOTFS_POSTPROCESS_COMMAND += "rootfs_debug_files;"
32rootfs_debug_files () {
33   #!/bin/sh -e
34   echo "${ROOTFS_DEBUG_FILES}" | sed -e 's/;/\n/g' | while read source target mode; do
35      if [ -e "$source" ]; then
36         mkdir -p $(dirname $target)
37         cp -a $source $target
38         [ -n "$mode" ] && chmod $mode $target
39      fi
40   done
41}
42