freebsd-nq/sys/tools/embed_mfs.sh
Ed Maste 2dd51e16ca embed_mfs: support embedding mfs into loader
The script originally supported embedding an mfs into ELF files or any
other type of file, because it searched for magic strings to mark the
beginning and end of the embeddable section. It was later modified to
read the section offset and length via readelf, which made it work for
ELF only. Restore the ability to update arbitrary file types by using
the readelf technique for ELF, and the magic string technique for all
others (including PE/COFF files like loader.efi).

Submitted by:	Zakary Nafziger <worldofzak@gmail.com>
MFC after:	1 month
Sponsored by:	The FreeBSD Foundation
Differential Revision:	https://reviews.freebsd.org/D12746
2017-12-19 19:44:06 +00:00

86 lines
3.1 KiB
Bash

#!/bin/sh
#
# SPDX-License-Identifier: BSD-2-Clause-FreeBSD
#
# Copyright (C) 2008 The FreeBSD Project. All rights reserved.
#
# Redistribution and use in source and binary forms, with or without
# modification, are permitted provided that the following conditions
# are met:
# 1. Redistributions of source code must retain the above copyright
# notice, this list of conditions and the following disclaimer.
# 2. Redistributions in binary form must reproduce the above copyright
# notice, this list of conditions and the following disclaimer in the
# documentation and/or other materials provided with the distribution.
#
# THIS SOFTWARE IS PROVIDED BY AUTHOR AND CONTRIBUTORS ``AS IS'' AND
# ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
# IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
# ARE DISCLAIMED. IN NO EVENT SHALL AUTHOR OR CONTRIBUTORS BE LIABLE
# FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
# DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
# OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
# HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
# LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
# OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
# SUCH DAMAGE.
#
# $FreeBSD$
#
# Embed an MFS image into the kernel body or the loader body (expects space
# reserved via MD_ROOT_SIZE (kernel) or MD_IMAGE_SIZE (loader))
#
# $1: kernel or loader filename
# $2: MFS image filename
#
if [ $# -ne 2 ]; then
echo "usage: $(basename $0) target mfs_image"
exit 0
fi
if [ ! -w "$1" ]; then
echo $1 not writable
exit 1
fi
mfs_size=`stat -f '%z' $2 2> /dev/null`
# If we can't determine MFS image size - bail.
[ -z ${mfs_size} ] && echo "Can't determine MFS image size" && exit 1
err_no_mfs="Can't locate mfs section within "
if [ `file -b $1 | grep -q '^ELF ..-bit .SB executable'` ]; then
sec_info=`elfdump -c $1 2> /dev/null | grep -A 5 -E "sh_name: oldmfs$"`
# If we can't find the mfs section within the given kernel - bail.
[ -z "${sec_info}" ] && echo "${err_no_mfs} $1" && exit 1
sec_size=`echo "${sec_info}" | awk '/sh_size/ {print $2}' 2>/dev/null`
sec_start=`echo "${sec_info}" | \
awk '/sh_offset/ {print $2}' 2>/dev/null`
else
#try to find start byte of MFS start flag otherwise - bail.
sec_start=`strings -at d $1 | grep "MFS Filesystem goes here"` || \
{ echo "${err_no_mfs} $1"; exit 1; }
sec_start=`echo ${sec_start} | awk '{print $1}'`
#try to find start byte of MFS end flag otherwise - bail.
sec_end=`strings -at d $1 | \
grep "MFS Filesystem had better STOP here"` || \
{ echo "${err_no_mfs} $1"; exit 1; }
sec_end=`echo ${sec_end} | awk '{print $1}'`
#calculate MFS section size
sec_size=`expr ${sec_end} - ${sec_start}`
fi
# If the mfs section size is smaller than the mfs image - bail.
[ ${sec_size} -lt ${mfs_size} ] && echo "MFS image too large" && exit 1
# Dump the mfs image into the mfs section
dd if=$2 ibs=8192 of=$1 obs=${sec_start} oseek=1 conv=notrunc 2> /dev/null && \
echo "MFS image embedded into $1" && exit 0