#!/usr/bin/bash
# Copyright (c) 2019 Michal Ambroz <rebus _AT seznam.cz>
#
# This file is distributed with same license as Volatility.
#
# Volatility is free software; you can redistribute it and/or modify
# it under the terms of the GNU General Public License as published by
# the Free Software Foundation; either version 2 of the License, or
# (at your option) any later version.
#
# Volatility is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
# GNU General Public License for more details.
#
# You should have received a copy of the GNU General Public License
# along with Volatility.  If not, see <http://www.gnu.org/licenses/>.
#

TOOLSDIR=/usr/share/python-volatility/tools/linux
PROFILEDIR=/usr/lib/python2.7/site-packages/volatility/plugins/overlays/linux


OSNAME=$(grep "^NAME=" /etc/os-release | cut -d "=" -f 2 | sed -e 's/"//g;')
OSVER=$(grep "^VERSION_ID=" /etc/os-release  | cut -d "=" -f 2 | sed -e 's/"//g;')
KERNEL=$(uname -r)

ZIPNAME="${OSNAME}_${OSVER}-${KERNEL}.zip"

if [ "x$1" = "x--help" ] ; then
	echo "Syntax:      $0"
	echo "Description: generate linux profile for use with Volatility based on the current running kernel"
	echo "             Profile will be stored to directory $PROFILEDIR"
	echo ""
	echo "Dependencies: dwarfdump(libdwarf-tools), libdwarf, elfutils-libelf, kernel-headers, make, gcc"
	exit 0
fi


DWARFDUMP=$(command -v dwarfdump 2>/dev/null)
if [ "$DWARFDUMP" = "" ] ; then
	echo "==== ERROR: tool dwarfdump is not installed. Please install the libdwarf-tools package."
	exit 1
fi

MYID=$(id -u)
if [ "$MYID" -ne 0 ] ; then
	echo -e "==== ERROR: Needs to run as root to be able to read the '/boot/System.map-${KERNEL}' of the current kernel and write the profile to: \n '${PROFILEDIR}/${ZIPNAME}'"
	exit 1
fi

TEMPDIR=$(mktemp -d)
if [ -d "$TEMPDIR" ] ; then
        echo "==== ERROR: failed to create temporary directory"
        exit 1
fi

cp "${TOOLSDIR}/Makefile ${TOOLSDIR}/module.c" "${TEMPDIR}/"
pushd "${TEMPDIR}" || exit 1

make

echo zip "${PROFILEDIR}/${ZIPNAME}" module.dwarf "/boot/System.map-${KERNEL}"
zip "${PROFILEDIR}/${ZIPNAME}" module.dwarf "/boot/System.map-${KERNEL}"

popd || exit 1
rm -rf "$TEMPDIR"