#!/bin/bash

KEXEC=/sbin/kexec

KDUMP_KERNELVER=""

KDUMP_KERNEL=""

KDUMP_COMMANDLINE=""

KEXEC_ARGS=""

KDUMP_CONFIG_FILE="/etc/kdump.conf"

KDUMP_LOG_PATH="/var/log"

MKDUMPRD="/sbin/mkdumprd -f"

DRACUT_MODULES_FILE="/usr/lib/dracut/modules.txt"

SAVE_PATH=/var/crash

SSH_KEY_LOCATION="/root/.ssh/kdump_id_rsa"

INITRD_CHECKSUM_LOCATION="/boot/.fadump_initrd_checksum"

DUMP_TARGET=""

DEFAULT_INITRD=""

DEFAULT_INITRD_BAK=""

KDUMP_INITRD=""

TARGET_INITRD=""

FADUMP_REGISTER_SYS_NODE="/sys/kernel/fadump_registered"

#kdump shall be the default dump mode

DEFAULT_DUMP_MODE="kdump"

image_time=0

standard_kexec_args="-d -p"

# Some default values in case /etc/sysconfig/kdump doesn't include

KDUMP_COMMANDLINE_REMOVE="hugepages hugepagesz slub_debug"

if [ -f /etc/sysconfig/kdump ]; then

	. /etc/sysconfig/kdump

fi

[[ $dracutbasedir ]] || dracutbasedir=/usr/lib/dracut

. $dracutbasedir/dracut-functions.sh

. /lib/kdump/kdump-lib.sh

#initiate the kdump logger

dlog_init

if [ $? -ne 0 ]; then

	echo "failed to initiate the kdump logger."

	exit 1

fi

single_instance_lock()

{

	local rc timeout=5

	exec 9>/var/lock/kdump

	if [ $? -ne 0 ]; then

		derror "Create file lock failed"

		exit 1

	fi

	flock -n 9

	rc=$?

	while [ $rc -ne 0 ]; do

		dinfo "Another app is currently holding the kdump lock; waiting for it to exit..."

		flock -w $timeout 9

		rc=$?

	done

}

determine_dump_mode()

{

	# Check if firmware-assisted dump is enabled

	# if yes, set the dump mode as fadump

	if is_fadump_capable; then

		dinfo "Dump mode is fadump"

		DEFAULT_DUMP_MODE="fadump"

	fi

	ddebug "DEFAULT_DUMP_MODE=$DEFAULT_DUMP_MODE"

}

save_core()

{

	coredir="/var/crash/`date +"%Y-%m-%d-%H:%M"`"

	mkdir -p $coredir

	ddebug "cp --sparse=always /proc/vmcore $coredir/vmcore-incomplete"

	cp --sparse=always /proc/vmcore $coredir/vmcore-incomplete

	if [ $? == 0 ]; then

		mv $coredir/vmcore-incomplete $coredir/vmcore

		dinfo "saved a vmcore to $coredir"

	else

		derror "failed to save a vmcore to $coredir"

	fi

	# pass the dmesg to Abrt tool if exists, in order

	# to collect the kernel oops message.

	# https://fedorahosted.org/abrt/

	if [ -x /usr/bin/dumpoops ]; then

		ddebug "makedumpfile --dump-dmesg $coredir/vmcore $coredir/dmesg"

		makedumpfile --dump-dmesg $coredir/vmcore $coredir/dmesg >/dev/null 2>&1

		ddebug "dumpoops -d $coredir/dmesg"

		dumpoops -d $coredir/dmesg >/dev/null 2>&1

		if [ $? == 0 ]; then

			dinfo "kernel oops has been collected by abrt tool"

		fi

	fi

}

rebuild_fadump_initrd()

{

	local target_initrd_tmp

	# this file tells the initrd is fadump enabled

	touch /tmp/fadump.initramfs

	target_initrd_tmp="$TARGET_INITRD.tmp"

	ddebug "rebuild fadump initrd: $target_initrd_tmp $DEFAULT_INITRD_BAK $KDUMP_KERNELVER"

	$MKDUMPRD $target_initrd_tmp --rebuild $DEFAULT_INITRD_BAK --kver $KDUMP_KERNELVER \

		-i /tmp/fadump.initramfs /etc/fadump.initramfs

	if [ $? != 0 ]; then

		derror "mkdumprd: failed to rebuild initrd with fadump support"

		rm -f /tmp/fadump.initramfs

		return 1

	fi

	rm -f /tmp/fadump.initramfs

	# updating fadump initrd

	ddebug "updating fadump initrd: $target_initrd_tmp $TARGET_INITRD"

	mv $target_initrd_tmp $TARGET_INITRD

	sync

	return 0

}

check_earlykdump_is_enabled()

{

	grep -q -w "rd.earlykdump" /proc/cmdline

	return $?

}

rebuild_kdump_initrd()

{

	ddebug "rebuild kdump initrd: $MKDUMPRD $TARGET_INITRD $KDUMP_KERNELVER"

	$MKDUMPRD $TARGET_INITRD $KDUMP_KERNELVER

	if [ $? != 0 ]; then

		derror "mkdumprd: failed to make kdump initrd"

		return 1

	fi

	if check_earlykdump_is_enabled; then

		dwarn "Tips: If early kdump is enabled, also require rebuilding the system initramfs to make the changes take effect for early kdump."

	fi

	return 0

}

rebuild_initrd()

{

	if [[ ! -w "$KDUMP_BOOTDIR" ]];then

		derror "$KDUMP_BOOTDIR does not have write permission. Can not rebuild $TARGET_INITRD"

		return 1

	fi

	if [ $DEFAULT_DUMP_MODE == "fadump" ]; then

		rebuild_fadump_initrd

	else

		rebuild_kdump_initrd

	fi

	return $?

}

#$1: the files to be checked with IFS=' '

check_exist()

{

	for file in $1; do

		if [ ! -e "$file" ]; then

			derror "Error: $file not found."

			return 1

		fi

	done

}

#$1: the files to be checked with IFS=' '

check_executable()

{

	for file in $1; do

		if [ ! -x "$file" ]; then

			derror "Error: $file is not executable."

			return 1

		fi

	done

}

backup_default_initrd()

{

	ddebug "backup default initrd: $DEFAULT_INITRD"

	if [ ! -f "$DEFAULT_INITRD" ]; then

		return

	fi

	if [ ! -e $DEFAULT_INITRD_BAK ]; then

		dinfo "Backing up $DEFAULT_INITRD before rebuild."

		# save checksum to verify before restoring

		sha1sum $DEFAULT_INITRD > $INITRD_CHECKSUM_LOCATION

		cp $DEFAULT_INITRD $DEFAULT_INITRD_BAK

		if [ $? -ne 0 ]; then

			dwarn "WARNING: failed to backup $DEFAULT_INITRD."

			rm -f $DEFAULT_INITRD_BAK

		fi

	fi

}

restore_default_initrd()

{

	ddebug "restore default initrd: $DEFAULT_INITRD"

	if [ ! -f "$DEFAULT_INITRD" ]; then

		return

	fi

	# If a backup initrd exists, we must be switching back from

	# fadump to kdump. Restore the original default initrd.

	if [ -f $DEFAULT_INITRD_BAK ] && [ -f $INITRD_CHECKSUM_LOCATION ]; then

		# verify checksum before restoring

		backup_checksum=`sha1sum $DEFAULT_INITRD_BAK | awk '{ print $1 }'`

		default_checksum=`cat $INITRD_CHECKSUM_LOCATION | awk '{ print $1 }'`

		if [ "$default_checksum" != "$backup_checksum" ]; then

			dwarn "WARNING: checksum mismatch! Can't restore original initrd.."

		else

			rm -f $INITRD_CHECKSUM_LOCATION

			mv $DEFAULT_INITRD_BAK $DEFAULT_INITRD

			if [[ $? -eq 0 ]]; then

				derror "Restoring original initrd as fadump mode is disabled."

				sync

			fi

		fi

	fi

}

check_config()

{

	local -A _opt_rec

	while read config_opt config_val; do

		if [ -z "$config_val" ]; then

			derror "Invalid kdump config value for option $config_opt"

			return 1

		fi

		case "$config_opt" in

		dracut_args)

			if [[ $config_val == *--mount* ]]; then

				if [ $(echo $config_val | grep -o "\-\-mount" | wc -l) -ne 1 ]; then

					derror "Multiple mount targets specified in one \"dracut_args\"."

					return 1

				fi

				config_opt=_target

			fi

			;;

		raw)

			if [ -d "/proc/device-tree/ibm,opal/dump" ]; then

				dwarn "WARNING: Won't capture opalcore when 'raw' dump target is used."

			fi

			config_opt=_target

			;;

		ext[234]|minix|btrfs|xfs|nfs|ssh)

			config_opt=_target

			;;

		sshkey|path|core_collector|kdump_post|kdump_pre|extra_bins|extra_modules|failure_action|default|final_action|force_rebuild|force_no_rebuild|fence_kdump_args|fence_kdump_nodes)

			;;

		net|options|link_delay|disk_timeout|debug_mem_level|blacklist)

			derror "Deprecated kdump config option: $config_opt. Refer to kdump.conf manpage for alternatives."

			return 1

			;;

		*)

			derror "Invalid kdump config option $config_opt"

			return 1

			;;

		esac

		if [ -n "${_opt_rec[$config_opt]}" ]; then

			if [ $config_opt == _target ]; then

				derror "More than one dump targets specified"

			else

				derror "Duplicated kdump config value of option $config_opt"

			fi

			return 1

		fi

		_opt_rec[$config_opt]="$config_val"

	done <<< "$(read_strip_comments $KDUMP_CONFIG_FILE)"

	check_failure_action_config || return 1

	check_final_action_config || return 1

	check_fence_kdump_config || return 1

	return 0

}

# get_pcs_cluster_modified_files <image timestamp>

# return list of modified file for fence_kdump modified in Pacemaker cluster

get_pcs_cluster_modified_files()

{

	local time_stamp

	local modified_files

	is_generic_fence_kdump && return 1

	is_pcs_fence_kdump || return 1

	time_stamp=`pcs cluster cib | xmllint --xpath 'string(/cib/@cib-last-written)' - | \

		xargs -0 date +%s --date`

	if [ -n $time_stamp -a $time_stamp -gt $image_time ]; then

		modified_files="cluster-cib"

	fi

	if [ -f $FENCE_KDUMP_CONFIG_FILE ]; then

		time_stamp=`stat -c "%Y" $FENCE_KDUMP_CONFIG_FILE`

		if [ "$time_stamp" -gt "$image_time" ]; then

			modified_files="$modified_files $FENCE_KDUMP_CONFIG_FILE"

		fi

	fi

	echo $modified_files

}

setup_initrd()

{

	prepare_kdump_bootinfo

	if [ $? -ne 0 ]; then

		derror "failed to prepare for kdump bootinfo."

		return 1

	fi

	DEFAULT_INITRD_BAK="$KDUMP_BOOTDIR/.$(basename $DEFAULT_INITRD).default"

	if [ $DEFAULT_DUMP_MODE == "fadump" ]; then

		TARGET_INITRD="$DEFAULT_INITRD"

		# backup initrd for reference before replacing it

		# with fadump aware initrd

		backup_default_initrd

	else

		TARGET_INITRD="$KDUMP_INITRD"

		# check if a backup of default initrd exists. If yes,

		# it signifies a switch from fadump mode. So, restore

		# the backed up default initrd.

		restore_default_initrd

	fi

}

check_files_modified()

{

	local modified_files=""

	#also rebuild when Pacemaker cluster conf is changed and fence kdump is enabled.

	modified_files=$(get_pcs_cluster_modified_files)

	EXTRA_BINS=`grep ^kdump_post $KDUMP_CONFIG_FILE | cut -d\  -f2`

	CHECK_FILES=`grep ^kdump_pre $KDUMP_CONFIG_FILE | cut -d\  -f2`

	HOOKS="/etc/kdump/post.d/ /etc/kdump/pre.d/"

	if [ -d /etc/kdump/post.d ]; then

		for file in /etc/kdump/post.d/*; do

			if [ -x "$file" ]; then

				POST_FILES="$POST_FILES $file"

			fi

		done

	fi

	if [ -d /etc/kdump/pre.d ]; then

		for file in /etc/kdump/pre.d/*; do

			if [ -x "$file" ]; then

				PRE_FILES="$PRE_FILES $file"

			fi

		done

	fi

	HOOKS="$HOOKS $POST_FILES $PRE_FILES"

	CORE_COLLECTOR=`grep ^core_collector $KDUMP_CONFIG_FILE | cut -d\  -f2`

	CORE_COLLECTOR=`type -P $CORE_COLLECTOR`

	# POST_FILES and PRE_FILES are already checked against executable, need not to check again.

	EXTRA_BINS="$EXTRA_BINS $CHECK_FILES"

	CHECK_FILES=`grep ^extra_bins $KDUMP_CONFIG_FILE | cut -d\  -f2-`

	EXTRA_BINS="$EXTRA_BINS $CHECK_FILES"

	files="$KDUMP_CONFIG_FILE $KDUMP_KERNEL $EXTRA_BINS $CORE_COLLECTOR"

	[[ -e /etc/fstab ]] && files="$files /etc/fstab"

	# Check for any updated extra module

	EXTRA_MODULES="$(grep ^extra_modules $KDUMP_CONFIG_FILE | sed 's/^extra_modules\s*//')"

	if [ -n "$EXTRA_MODULES" ]; then

		if [ -e /lib/modules/$KDUMP_KERNELVER/modules.dep ]; then

			files="$files /lib/modules/$KDUMP_KERNELVER/modules.dep"

		fi

		for _module in $EXTRA_MODULES; do

			_module_file="$(modinfo --set-version "$KDUMP_KERNELVER" --filename "$_module" 2>/dev/null)"

			if [[ $? -eq 0 ]]; then

				files="$files $_module_file"

				for _dep_modules in $(modinfo -F depends $_module | tr ',' ' '); do

				    files="$files $(modinfo --set-version "$KDUMP_KERNELVER" --filename $_dep_modules 2>/dev/null)"

				done

			else

				# If it's not a module nor builtin, give an error

				if ! ( modprobe --set-version "$KDUMP_KERNELVER" --dry-run "$_module" &>/dev/null ); then

					dwarn "Module $_module not found"

				fi

			fi

		done

	fi

	# HOOKS is mandatory and need to check the modification time

	files="$files $HOOKS"

	check_exist "$files" && check_executable "$EXTRA_BINS"

	[ $? -ne 0 ] && return 2

	for file in $files; do

		if [ -e "$file" ]; then

			time_stamp=`stat -c "%Y" $file`

			if [ "$time_stamp" -gt "$image_time" ]; then

				modified_files="$modified_files $file"

			fi

			if [ -L "$file" ]; then

				file=$(readlink -m $file)

				time_stamp=`stat -c "%Y" $file`

				if [ "$time_stamp" -gt "$image_time" ]; then

					modified_files="$modified_files $file"

				fi

			fi

		else

			dwarn "$file doesn't exist"

		fi

	done

	if [ -n "$modified_files" ]; then

		dinfo "Detected change(s) in the following file(s): $modified_files"

		return 1

	fi

	return 0

}

check_drivers_modified()

{

	local _target _new_drivers _old_drivers _module_name _module_filename

	# If it's dump target is on block device, detect the block driver

	_target=$(get_block_dump_target)

	if [[ -n "$_target" ]]; then

		_record_block_drivers() {

			local _drivers

			_drivers=$(udevadm info -a "/dev/block/$1" | sed -n 's/\s*DRIVERS=="\(\S\+\)"/\1/p')

			for _driver in $_drivers; do

				if ! [[ " $_new_drivers " == *" $_driver "* ]]; then

					_new_drivers="$_new_drivers $_driver"

				fi

			done

			ddebug "MAJ:MIN=$1 drivers='$_drivers'"

		}

		check_block_and_slaves_all _record_block_drivers "$(get_maj_min "$_target")"

	fi

	# Include watchdog drivers if watchdog module is not omitted

	is_dracut_mod_omitted watchdog || _new_drivers+=" $(get_watchdog_drvs)"

	[ -z "$_new_drivers" ] && return 0

	_old_drivers="$(lsinitrd $TARGET_INITRD -f /usr/lib/dracut/hostonly-kernel-modules.txt | tr '\n' ' ')"

	ddebug "Modules required for kdump: '$_new_drivers'"

	ddebug "Modules included in old initramfs: '$_old_drivers'"

	for _driver in $_new_drivers; do

		# Skip deprecated/invalid driver name or built-in module

		_module_name=$(modinfo --set-version "$KDUMP_KERNELVER" -F name $_driver 2>/dev/null)

		_module_filename=$(modinfo --set-version "$KDUMP_KERNELVER" -n $_driver 2>/dev/null)

		if [ $? -ne 0 ] || [ -z "$_module_name" ] || [[ "$_module_filename" = *"(builtin)"* ]]; then

			continue

		fi

		if ! [[ " $_old_drivers " == *" $_module_name "* ]]; then

			dinfo "Detected change in block device driver, new loaded module: $_module_name"

			return 1

		fi

	done

}

check_fs_modified()

{

	local _old_dev _old_mntpoint _old_fstype

	local _new_dev _new_mntpoint _new_fstype

	local _target _dracut_args

	# No need to check in case of mount target specified via "dracut_args".

	if is_mount_in_dracut_args; then

		return 0

	fi

	# No need to check in case of raw target.

	# Currently we do not check also if ssh/nfs target is specified

	if is_ssh_dump_target || is_nfs_dump_target || is_raw_dump_target; then

		return 0

	fi

	_target=$(get_block_dump_target)

	_new_fstype=$(get_fs_type_from_target $_target)

	if [[ -z "$_target" ]] || [[ -z "$_new_fstype" ]];then

		derror "Dump target is invalid"

		return 2

	fi

	ddebug "_target=$_target _new_fstype=$_new_fstype"

	_new_dev=$(kdump_get_persistent_dev $_target)

	if [ -z "$_new_dev" ]; then

		perror "Get persistent device name failed"

		return 2

	fi

	_new_mntpoint="$(get_kdump_mntpoint_from_target $_target)"

	_dracut_args=$(lsinitrd $TARGET_INITRD -f usr/lib/dracut/build-parameter.txt)

	if [[ -z "$_dracut_args" ]];then

		dwarn "Warning: No dracut arguments found in initrd"

		return 0

	fi

	# if --mount argument present then match old and new target, mount

	# point and file system. If any of them mismatches then rebuild

	echo $_dracut_args | grep "\-\-mount" &> /dev/null

	if [[ $? -eq 0 ]];then

		set -- $(echo $_dracut_args | awk -F "--mount '" '{print $2}' | cut -d' ' -f1,2,3)

		_old_dev=$1

		_old_mntpoint=$2

		_old_fstype=$3

		[[ $_new_dev = $_old_dev && $_new_mntpoint = $_old_mntpoint && $_new_fstype = $_old_fstype ]] && return 0

	# otherwise rebuild if target device is not a root device

	else

		[[ "$_target" = "$(get_root_fs_device)" ]] && return 0

	fi

	dinfo "Detected change in File System"

	return 1

}

# returns 0 if system is not modified

# returns 1 if system is modified

# returns 2 if system modification is invalid

check_system_modified()

{

	local ret

	[[ -f $TARGET_INITRD ]] || return 1

	check_files_modified

	ret=$?

	if [ $ret -ne 0 ]; then

		return $ret

	fi

	check_fs_modified

	ret=$?

	if [ $ret -ne 0 ]; then

		return $ret

	fi

	check_drivers_modified

	ret=$?

	if [ $ret -ne 0 ]; then

		return $ret

	fi

	return 0

}

check_rebuild()

{

	local capture_capable_initrd="1"

	local _force_rebuild force_rebuild="0"

	local _force_no_rebuild force_no_rebuild="0"

	local ret system_modified="0"

	setup_initrd

	if [ $? -ne 0 ]; then

		return 1

	fi

	_force_no_rebuild=`grep ^force_no_rebuild $KDUMP_CONFIG_FILE 2>/dev/null`

	if [ $? -eq 0 ]; then

		force_no_rebuild=`echo $_force_no_rebuild | cut -d' '  -f2`

		if [ "$force_no_rebuild" != "0" ] && [ "$force_no_rebuild" != "1" ];then

			derror "Error: force_no_rebuild value is invalid"

			return 1

		fi

	fi

	_force_rebuild=`grep ^force_rebuild $KDUMP_CONFIG_FILE 2>/dev/null`

	if [ $? -eq 0 ]; then

		force_rebuild=`echo $_force_rebuild | cut -d' '  -f2`

		if [ "$force_rebuild" != "0" ] && [ "$force_rebuild" != "1" ];then

			derror "Error: force_rebuild value is invalid"

			return 1

		fi

	fi

	if [[ "$force_no_rebuild" == "1" && "$force_rebuild" == "1" ]]; then

		derror "Error: force_rebuild and force_no_rebuild are enabled simultaneously in kdump.conf"

		return 1

	fi

	# Will not rebuild kdump initrd

	if [ "$force_no_rebuild" == "1" ]; then

		return 0

	fi

	#check to see if dependent files has been modified

	#since last build of the image file

	if [ -f $TARGET_INITRD ]; then

		image_time=`stat -c "%Y" $TARGET_INITRD 2>/dev/null`

		#in case of fadump mode, check whether the default/target

		#initrd is already built with dump capture capability

		if [ "$DEFAULT_DUMP_MODE" == "fadump" ]; then

			capture_capable_initrd=$(lsinitrd -f $DRACUT_MODULES_FILE $TARGET_INITRD | grep ^kdumpbase$ | wc -l)

		fi

	fi

	check_system_modified

	ret=$?

	if [ $ret -eq 2 ]; then

		return 1

	elif [ $ret -eq 1 ];then

		system_modified="1"

	fi

	if [ $image_time -eq 0 ]; then

		dinfo "No kdump initial ramdisk found."

	elif [ "$capture_capable_initrd" == "0" ]; then

		dinfo "Rebuild $TARGET_INITRD with dump capture support"

	elif [ "$force_rebuild" != "0" ]; then

		dinfo "Force rebuild $TARGET_INITRD"

	elif [ "$system_modified" != "0" ]; then

		:

	else

		return 0

	fi

	dinfo "Rebuilding $TARGET_INITRD"

	rebuild_initrd

	return $?

}

# Load the kdump kernel specified in /etc/sysconfig/kdump

# If none is specified, try to load a kdump kernel with the same version

# as the currently running kernel.

load_kdump()

{

	local ret

	KEXEC_ARGS=$(prepare_kexec_args "${KEXEC_ARGS}")

	KDUMP_COMMANDLINE=$(prepare_cmdline "${KDUMP_COMMANDLINE}" "${KDUMP_COMMANDLINE_REMOVE}" "${KDUMP_COMMANDLINE_APPEND}")

	# For secureboot enabled machines, use new kexec file based syscall.

	# Old syscall will always fail as it does not have capability to

	# to kernel signature verification.

	if is_secure_boot_enforced; then

		dinfo "Secure Boot is enabled. Using kexec file based syscall."

		KEXEC_ARGS="$KEXEC_ARGS -s"

	fi

	ddebug "$KEXEC $KEXEC_ARGS $standard_kexec_args --command-line=$KDUMP_COMMANDLINE --initrd=$TARGET_INITRD $KDUMP_KERNEL"

	# The '12' represents an intermediate temporary file descriptor

	# to store the standard error file descriptor '2', and later

	# restore the error file descriptor with the file descriptor '12'

	# and release it.

	exec 12>&2

	exec 2>> $KDUMP_LOG_PATH/kdump.log

	PS4='+ $(date "+%Y-%m-%d %H:%M:%S") ${BASH_SOURCE}@${LINENO}: '

	set -x

	$KEXEC $KEXEC_ARGS $standard_kexec_args \

		--command-line="$KDUMP_COMMANDLINE" \

		--initrd=$TARGET_INITRD $KDUMP_KERNEL

	ret=$?

	set +x

	exec 2>&12 12>&-

	if [ $ret == 0 ]; then

		dinfo "kexec: loaded kdump kernel"

		return 0

	else

		derror "kexec: failed to load kdump kernel"

		return 1

	fi

}

check_ssh_config()

{

	while read config_opt config_val; do

		case "$config_opt" in

		sshkey)

			# remove inline comments after the end of a directive.

			if [ -f "$config_val" ]; then

				# canonicalize the path

				SSH_KEY_LOCATION=$(/usr/bin/readlink -m $config_val)

			else

				dwarn "WARNING: '$config_val' doesn't exist, using default value '$SSH_KEY_LOCATION'"

			fi

			;;

		path)

			SAVE_PATH=$config_val

			;;

		ssh)

			DUMP_TARGET=$config_val

			;;

		*)

			;;

		esac

	done <<< "$(read_strip_comments $KDUMP_CONFIG_FILE)"

	#make sure they've configured kdump.conf for ssh dumps

	local SSH_TARGET=`echo -n $DUMP_TARGET | sed -n '/.*@/p'`

	if [ -z "$SSH_TARGET" ]; then

		return 1

	fi

	return 0

}

# ipv6 host address may takes a long time to be ready.

# Instead of checking against ipv6 address, we just check the network reachable

# by the return val of 'ssh'

check_and_wait_network_ready()

{

	local start_time=$(date +%s)

	local warn_once=1

	local cur

	local diff

	local retval

	local errmsg

	while true; do

		errmsg=$(ssh -i $SSH_KEY_LOCATION -o BatchMode=yes $DUMP_TARGET mkdir -p $SAVE_PATH 2>&1)

		retval=$?

		# ssh exits with the exit status of the remote command or with 255 if an error occurred

		if [ $retval -eq 0 ]; then

			return 0

		elif [ $retval -ne 255 ]; then

			derror "Could not create $DUMP_TARGET:$SAVE_PATH, you should check the privilege on server side"

			return 1

		fi

		# if server removes the authorized_keys or, no /root/.ssh/kdump_id_rsa

		ddebug "$errmsg"

		echo $errmsg | grep -q "Permission denied\|No such file or directory\|Host key verification failed" &> /dev/null

		if [ $? -eq 0 ]; then

			derror "Could not create $DUMP_TARGET:$SAVE_PATH, you probably need to run \"kdumpctl propagate\""

			return 1

		fi

		if [ $warn_once -eq 1 ]; then

			dwarn "Network dump target is not usable, waiting for it to be ready..."

			warn_once=0

		fi

		cur=$(date +%s)

		let "diff = $cur - $start_time"

		# 60s time out

		if [ $diff -gt 180 ]; then

			break;

		fi

		sleep 1

	done

	dinfo "Could not create $DUMP_TARGET:$SAVE_PATH, ipaddr is not ready yet. You should check network connection"

	return 1

}

check_ssh_target()

{

	check_and_wait_network_ready

	if [ $? -ne 0 ]; then

		return 1

	fi

	return 0

}

propagate_ssh_key()

{

	check_ssh_config

	if [ $? -ne 0 ]; then

		derror "No ssh config specified in $KDUMP_CONFIG_FILE.  Can't propagate"

		exit 1

	fi

	local KEYFILE=$SSH_KEY_LOCATION

	local errmsg="Failed to propagate ssh key"

	#Check to see if we already created key, if not, create it.

	if [ -f $KEYFILE ]; then

		dinfo "Using existing keys..."

	else

		dinfo "Generating new ssh keys... "

		/usr/bin/ssh-keygen -t rsa -f $KEYFILE -N "" 2>&1 > /dev/null

		dinfo "done."

	fi

	#now find the target ssh user and server to contact.

	SSH_USER=`echo $DUMP_TARGET | cut -d\  -f2 | cut -d@ -f1`

	SSH_SERVER=`echo $DUMP_TARGET | sed -e's/\(.*@\)\(.*$\)/\2/'`

	#now send the found key to the found server

	ssh-copy-id -i $KEYFILE $SSH_USER@$SSH_SERVER

	RET=$?

	if [ $RET == 0 ]; then

		dinfo "$KEYFILE has been added to ~$SSH_USER/.ssh/authorized_keys on $SSH_SERVER"

		return 0

	else

		derror "$errmsg, $KEYFILE failed in transfer to $SSH_SERVER"

		exit 1

	fi

}

show_reserved_mem()

{

    local mem=$(cat /sys/kernel/kexec_crash_size)

    local mem_mb=$(expr $mem / 1024 / 1024)

    dinfo "Reserved "$mem_mb"MB memory for crash kernel"

}

check_current_fadump_status()

{

	# Check if firmware-assisted dump has been registered.

	rc=`cat $FADUMP_REGISTER_SYS_NODE`

	[ $rc -eq 1 ] && return 0

	return 1

}

check_current_status()

{

	if [ $DEFAULT_DUMP_MODE == "fadump" ]; then

		check_current_fadump_status

	else

		check_current_kdump_status

	fi

	return $?

}

save_raw()

{

	local kdump_dir

	local raw_target

	raw_target=$(awk '$1 ~ /^raw$/ { print $2; }' $KDUMP_CONFIG_FILE)

	[ -z "$raw_target" ] && return 0

	[ -b "$raw_target" ] || {

		derror "raw partition $raw_target not found"

		return 1

	}

	check_fs=$(lsblk --nodeps -npo FSTYPE $raw_target)

	if [[ $(echo $check_fs | wc -w) -ne 0 ]]; then

		dwarn "Warning: Detected '$check_fs' signature on $raw_target, data loss is expected."

		return 0

	fi

	kdump_dir=`grep ^path $KDUMP_CONFIG_FILE | cut -d' '  -f2-`

	if [ -z "${kdump_dir}" ]; then

		coredir="/var/crash/`date +"%Y-%m-%d-%H:%M"`"

	else

		coredir="${kdump_dir}/`date +"%Y-%m-%d-%H:%M"`"

	fi

	mkdir -p "$coredir"

	[ -d "$coredir" ] || {

		derror "failed to create $coredir"

		return 1

	}

	if makedumpfile -R $coredir/vmcore <$raw_target >/dev/null 2>&1; then

		# dump found

		dinfo "Dump saved to $coredir/vmcore"

		# wipe makedumpfile header

		dd if=/dev/zero of=$raw_target bs=1b count=1 2>/dev/null

	else

		rm -rf "$coredir"

	fi

	return 0

}