Chromium Code Reviews
chromiumcodereview-hr@appspot.gserviceaccount.com (chromiumcodereview-hr) | Please choose your nickname with Settings | Help | Chromium Project | Gerrit Changes | Sign out
(148)

Unified Diff: verify_rootfs_chksum.sh

Issue 3452013: Issue 6821: script to verify rootfs integrity against value stored in kernel (Closed) Base URL: http://git.chromium.org/git/crosutils.git
Patch Set: fix per feedback Created 10 years, 3 months ago
Use n/p to move between diff chunks; N/P to move between comments. Draft comments are only viewable by you.
Jump to:
View side-by-side diff with in-line comments
Download patch
« no previous file with comments | « no previous file | no next file » | no next file with comments »
Expand Comments ('e') | Collapse Comments ('c') | Show Comments Hide Comments ('s')
Index: verify_rootfs_chksum.sh
diff --git a/verify_rootfs_chksum.sh b/verify_rootfs_chksum.sh
new file mode 100755
index 0000000000000000000000000000000000000000..9a8012dfbad4a510c2e3fefded8516a570703cdf
--- /dev/null
+++ b/verify_rootfs_chksum.sh
@@ -0,0 +1,100 @@
+#!/bin/bash
+#
+# Copyright (c) 2010 The Chromium OS Authors. All rights reserved.
+# Use of this source code is governed by a BSD-style license that can be
+# found in the LICENSE file.
+
+# Script to verify integrity of root file system for a GPT-based image
+
+# Load functions and constants
+. "$(dirname "$0")/common.sh" || exit 1
+. "$(dirname "$0")/chromeos-common.sh" || exit 1
+
+# Needed for partoffset and partsize calls
+locate_gpt
+
+# Script must be run inside the chroot.
+restart_in_chroot_if_needed $*
+
+DEFINE_string image "" "Device or an image path. Default: (empty)."
+
+# Parse command line.
+FLAGS "$@" || exit 1
+eval set -- "${FLAGS_ARGV}"
+
+if [ -z $FLAGS_image ] ; then
+ die "Use --from to specify a device or an image file."
+fi
+
+# Turn path into an absolute path.
+FLAGS_image=$(eval readlink -f ${FLAGS_image})
+
+# Abort early if we can't find the image
+if [ ! -b ${FLAGS_image} ] && [ ! -f $FLAGS_image ] ; then
+ die "No image found at $FLAGS_image"
+fi
+
+set -e
+
+function get_partitions() {
+ if [ -b ${FLAGS_image} ] ; then
+ KERNEL_IMG=$(make_partition_dev "${FLAGS_image}" 2)
+ ROOTFS_IMG=$(make_partition_dev "${FLAGS_image}" 3)
+ return
+ fi
+
+ KERNEL_IMG=$(mktemp)
+ ROOTFS_IMG=$(mktemp)
+ local kernel_offset=$(partoffset "${FLAGS_image}" 2)
+ local kernel_count=$(partsize "${FLAGS_image}" 2)
+ local rootfs_offset=$(partoffset "${FLAGS_image}" 3)
+ local rootfs_count=$(partsize "${FLAGS_image}" 3)
+
+ # TODO(tgao): use loop device to save 1GB in temp space
+ dd if="${FLAGS_image}" of=${KERNEL_IMG} bs=512 skip=${kernel_offset} \
+ count=${kernel_count} &>/dev/null
+ dd if="${FLAGS_image}" of=${ROOTFS_IMG} bs=512 skip=${rootfs_offset} \
+ count=${rootfs_count} &>/dev/null
+}
+
+function cleanup() {
+ for i in ${KERNEL_IMG} ${ROOTFS_IMG}
+ do
+ if [ ! -b ${i} ]; then
+ rm -f ${i}
+ fi
+ done
+}
+
+get_partitions
+
+# Logic below extracted from src/platform/installer/chromeos-setimage
+DUMP_KERNEL_CONFIG=/usr/bin/dump_kernel_config
+KERNEL_CONFIG=$(sudo "${DUMP_KERNEL_CONFIG}" "${KERNEL_IMG}")
+kernel_cfg="$(echo "${KERNEL_CONFIG}" | sed -e 's/.*dm="\([^"]*\)".*/\1/g' |
+ cut -f2- -d,)"
+rootfs_sectors=$(echo ${kernel_cfg} | cut -f2 -d' ')
+verity_depth=$(echo ${kernel_cfg} | cut -f7 -d' ')
+verity_algorithm=$(echo ${kernel_cfg} | cut -f8 -d' ')
+
+# Compute the rootfs hash tree
+VERITY=/bin/verity
+table="vroot none ro,"$(sudo "${VERITY}" create \
+ ${verity_depth} \
+ "${verity_algorithm}" \
+ "${ROOTFS_IMG}" \
+ $((rootfs_sectors / 8)) \
+ /dev/null)
+
+expected_hash=$(echo ${kernel_cfg} | cut -f9 -d' ')
+generated_hash=$(echo ${table} | cut -f2- -d, | cut -f9 -d' ')
+
+cleanup
+
+if [ "${expected_hash}" != "${generated_hash}" ]; then
+ warn "expected hash = ${expected_hash}"
+ warn "actual hash = ${generated_hash}"
+ die "Root filesystem has been modified unexpectedly!"
+else
+ info "Root filesystem checksum match!"
+fi
« no previous file with comments | « no previous file | no next file » | no next file with comments »

Powered by Google App Engine
This is Rietveld 408576698