diskimage-builder/elements/ironic-agent/cleanup.d/99-ramdisk-create
Ian Wienand 672705831f Add a best-effort sudo safety check
As motivation for this; we have had two breakouts of dib in recent
memory.  One was a failure to unmount through symlinks in the core
code (I335316019ef948758392b03e91f9869102a472b9) and the other was
removing host keys on the build-system
(Ib01d71ff9415a0ae04d963f6e380aab9ac2260ce).

For the most part, dib runs unprivileged.  Bits of the core code are
hopefully well tested (modulo bugs like the first one!).  We give free
reign inside the chroot (although there is still some potential there
for adverse external affects via bind mounts).  Where we could be a
bit safer (and could have prevented at least the second of these
breakouts) is with some better checking that the "sudo" calls
*outside* the chroot at least looked sane.

This adds a basic check that we're using chroot or image paths when
calling sudo in those parts of elements that run *outside* the chroot.
Various files are updated to accomodate this check; mostly by just
ignoring it for existing code (I have not audited these calls).

Nobody is pretending this type of checking makes dib magically safe,
or removes the issues with it needing to do things as root during the
build.  But this can help find egregious errors like the key removal.

Change-Id: I161a5aea1d29dcdc7236f70d372c53246ec73749
2016-05-09 15:41:38 +10:00

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#!/bin/bash
# dib-lint: disable=safe_sudo
if [ "${DIB_DEBUG_TRACE:-0}" -gt 0 ]; then
set -x
fi
set -eu
set -o pipefail
[ -n "$TARGET_ROOT" ]
source $_LIB/img-functions
IMAGE_PATH=$(readlink -f $IMAGE_NAME)
cd $TARGET_ROOT
echo "#disabled" > ./tmp/fstab.new
sudo mv ./tmp/fstab.new ./etc/fstab
sudo ln -s ./sbin/init ./
# Remove python object files, they're not particularly useful for a ramdisk
sudo find ./usr -name "*.pyc" -or -name "*.pyo" -delete
# Note: The pci.ids, which is used by lshw, locate on Ubuntu
# in /usr/share/misc. Therefore we are removing only the
# ./usr/share/misc/m* (will remove the magic and magic.mgc files).
# on RHEL pci.ids is locate on /usr/share/hwdata/pci.ids.
sudo find . -xdev \
-path './sys/*' -prune -o \
-path './tmp/*' -prune -o \
-path './boot/*' -prune -o \
-path './root/.cache' -prune -o \
-path './usr/lib/locale/*' -prune -o \
-path './usr/share/doc/*' -prune -o \
-path './usr/share/man/*' -prune -o \
-path './usr/share/info/*' -prune -o \
-path './usr/share/licenses/*' -prune -o \
-path './usr/share/misc/m*' -prune -o \
-print | sudo cpio -o -H newc | gzip > ${IMAGE_PATH}.initramfs
select_boot_kernel_initrd $TARGET_ROOT
sudo cp $BOOTDIR/$KERNEL ${IMAGE_PATH}.kernel
# TODO(lucasagomes): Create a hard link for the .vmlinuz file to keep
# it backward compatible. Remove it after it has been consistent and
# documented in both places for at least one full OpenStack release cycle
echo "WARNING: The kernel extension .vmlinuz has been deprecated. Please rely on the file with the extension .kernel instead."
sudo rm -f ${IMAGE_PATH}.vmlinuz
sudo ln ${IMAGE_PATH}.kernel ${IMAGE_PATH}.vmlinuz