#!/bin/bash

kdump_module_init() {
    if ! [[ -d "${initdir}/tmp" ]]; then
        mkdir -p "${initdir}/tmp"
    fi

    . /lib/kdump/kdump-lib.sh
}

check() {
    [[ $debug ]] && set -x
    #kdumpctl sets this explicitly
    if [[ -z "$IN_KDUMP" ]] || [[ ! -f /etc/kdump.conf ]]
    then
        return 1
    fi
    return 0
}

depends() {
    local _dep="base shutdown"

    kdump_module_init

    add_opt_module() {
        [[ " $omit_dracutmodules " != *\ $1\ * ]] && _dep="$_dep $1"
    }

    if is_squash_available; then
        add_opt_module squash
    else
        dwarning "Required modules to build a squashed kdump image is missing!"
    fi

    if is_wdt_active; then
        add_opt_module watchdog
    fi

    if is_ssh_dump_target; then
        _dep="$_dep ssh-client"
    fi

    if [[ "$(uname -m)" = "s390x" ]]; then
        _dep="$_dep znet"
    fi

    if [[ -n "$( ls -A /sys/class/drm 2>/dev/null )" ]] || [[ -d /sys/module/hyperv_fb ]]; then
        add_opt_module drm
    fi

    if is_generic_fence_kdump || is_pcs_fence_kdump; then
        _dep="$_dep network"
    fi

    echo "$_dep"
}

kdump_is_bridge() {
     [[ -d /sys/class/net/"$1"/bridge ]]
}

kdump_is_bond() {
     [[ -d /sys/class/net/"$1"/bonding ]]
}

kdump_is_team() {
     [[ -f /usr/bin/teamnl ]] && teamnl "$1" ports &> /dev/null
}

kdump_is_vlan() {
     [[ -f /proc/net/vlan/"$1" ]]
}

# $1: netdev name
source_ifcfg_file() {
    local ifcfg_file

    dwarning "Network Scripts are deprecated. You are encouraged to set up network by NetworkManager."
    ifcfg_file=$(get_ifcfg_filename "$1")
    if [[ -f "${ifcfg_file}" ]]; then
        . "${ifcfg_file}"
    else
        dwarning "The ifcfg file of $1 is not found!"
    fi
}

# $1: nmcli connection show output
kdump_setup_dns() {
    local _netdev="$1"
    local _nm_show_cmd="$2"
    local _nameserver _dns _tmp array
    local _dnsfile=${initdir}/etc/cmdline.d/42dns.conf

    _tmp=$(get_nmcli_value_by_field "$_nm_show_cmd" "IP4.DNS")
    # shellcheck disable=SC2206
    array=( ${_tmp//|/ } )
    if [[ ${array[*]} ]]; then
        for _dns in "${array[@]}"
        do
            echo "nameserver=$_dns" >> "$_dnsfile"
        done
    else
        dwarning "Failed to get DNS info via nmcli output. Now try sourcing ifcfg script"
        source_ifcfg_file "$_netdev"
        [[ -n "$DNS1" ]] && echo "nameserver=$DNS1" > "$_dnsfile"
        [[ -n "$DNS2" ]] && echo "nameserver=$DNS2" >> "$_dnsfile"
    fi

    while read -r content;
    do
        _nameserver=$(echo "$content" | grep ^nameserver)
        [[ -z "$_nameserver" ]] && continue

        _dns=$(echo "$_nameserver" | awk '{print $2}')
        [[ -z "$_dns" ]] && continue

        if [[ ! -f $_dnsfile ]] || ! grep -q "$_dns" "$_dnsfile" ; then
            echo "nameserver=$_dns" >> "$_dnsfile"
        fi
    done < "/etc/resolv.conf"
}

# $1: repeat times
# $2: string to be repeated
# $3: separator
repeatedly_join_str() {
    local _count="$1"
    local _str="$2"
    local _separator="$3"
    local i _res

    if [[ "$_count" -le 0 ]]; then
        echo -n ""
        return
    fi

    i=0
    _res="$_str"
    ((_count--))

    while [[ "$i" -lt "$_count" ]]; do
        ((i++))
        _res="${_res}${_separator}${_str}"
    done
    echo -n "$_res"
}

# $1: prefix
# $2: ipv6_flag="-6" indicates it's IPv6
# Given a prefix, calculate the netmask (equivalent of "ipcalc -m")
# by concatenating three parts,
#  1) the groups with all bits set 1
#  2) a group with partial bits set to 0
#  3) the groups with all bits set to 0
cal_netmask_by_prefix() {
    local _prefix="$1"
    local _ipv6_flag="$2" _ipv6
    local _bits_per_octet=8
    local _count _res _octets_per_group _octets_total _seperator _total_groups
    local _max_group_value _max_group_value_repr _bits_per_group _tmp _zero_bits

    if [[ "$_ipv6_flag" == "-6" ]]; then
        _ipv6=1
    else
        _ipv6=0
    fi

    if [[ "$_prefix" -lt 0  ||  "$_prefix" -gt 128 ]] || \
        ( ((!_ipv6)) && [[ "$_prefix" -gt 32 ]] ); then
        derror "Bad prefix:$_prefix for calculating netmask"
        exit 1
    fi

    if ((_ipv6)); then
        _octets_per_group=2
        _octets_total=16
        _seperator=":"
    else
        _octets_per_group=1
        _octets_total=4
        _seperator="."
    fi

    _total_groups=$((_octets_total/_octets_per_group))
    _bits_per_group=$((_octets_per_group * _bits_per_octet))
    _max_group_value=$(((1 << _bits_per_group) - 1))

    if ((_ipv6)); then
        _max_group_value_repr=$(printf "%x" $_max_group_value)
    else
        _max_group_value_repr="$_max_group_value"
    fi

    _count=$((_prefix/_octets_per_group/_bits_per_octet))
    _first_part=$(repeatedly_join_str "$_count" "$_max_group_value_repr" "$_seperator")
    _res="$_first_part"

    _tmp=$((_octets_total*_bits_per_octet-_prefix))
    _zero_bits=$((_tmp % _bits_per_group))
    if [[ "$_zero_bits" -ne 0 ]]; then
        _second_part=$((_max_group_value >> _zero_bits << _zero_bits))
        if ((_ipv6)); then
            _second_part=$(printf "%x" $_second_part)
        fi
        ((_count++))
        if [[ -z "$_first_part" ]]; then
            _res="$_second_part"
        else
            _res="${_first_part}${_seperator}${_second_part}"
        fi
    fi

    _count=$((_total_groups-_count))
    if [[ "$_count" -eq 0 ]]; then
        echo -n "$_res"
        return
    fi

    if ((_ipv6)) && [[ "$_count" -gt 1 ]] ; then
        # use condensed notion for IPv6
        _third_part=":"
    else
        _third_part=$(repeatedly_join_str "$_count" "0" "$_seperator")
    fi

    if [[ -z "$_res" ]] && ((!_ipv6)) ; then
        echo -n "${_third_part}"
    else
        echo -n "${_res}${_seperator}${_third_part}"
    fi
}

#$1: netdev name
#$2: srcaddr
#if it use static ip echo it, or echo null
kdump_static_ip() {
    local _netdev="$1" _srcaddr="$2" kdumpnic="$3" _ipv6_flag
    local _netmask _gateway _ipaddr _target _nexthop _prefix

    _ipaddr=$(ip addr show dev "$_netdev" permanent | awk "/ $_srcaddr\/.* /{print \$2}")

    if is_ipv6_address "$_srcaddr"; then
        _ipv6_flag="-6"
    fi

    if [[ -n "$_ipaddr" ]]; then
        _gateway=$(ip $_ipv6_flag route list dev "$_netdev" | \
                awk '/^default /{print $3}' | head -n 1)

        if [[ "x" !=  "x"$_ipv6_flag ]]; then
            # _ipaddr="2002::56ff:feb6:56d5/64", _netmask is the number after "/"
            _netmask=${_ipaddr#*\/}
            _srcaddr="[$_srcaddr]"
            _gateway="[$_gateway]"
        else
            _prefix=$(cut -d'/' -f2 <<< "$_ipaddr")
            _netmask=$(cal_netmask_by_prefix "$_prefix" "$_ipv6_flag")
            if [[ "$?" -ne 0 ]]; then
                derror "Failed to calculate netmask for $_ipaddr"
                exit 1
            fi
        fi
        echo -n "${_srcaddr}::${_gateway}:${_netmask}::"
    fi

    /sbin/ip $_ipv6_flag route show | grep -v default |\
    grep ".*via.* $_netdev " | grep -v "^[[:space:]]*nexthop" |\
    while read -r _route; do
        _target=$(echo "$_route" | awk '{print $1}')
        _nexthop=$(echo "$_route" | awk '{print $3}')
        if [[ "x" !=  "x"$_ipv6_flag ]]; then
            _target="[$_target]"
            _nexthop="[$_nexthop]"
        fi
        echo "rd.route=$_target:$_nexthop:$kdumpnic"
    done >> "${initdir}/etc/cmdline.d/45route-static.conf"

    kdump_handle_mulitpath_route "$_netdev" "$_srcaddr" "$kdumpnic"
}

kdump_handle_mulitpath_route() {
    local _netdev="$1" _srcaddr="$2" kdumpnic="$3" _ipv6_flag
    local _target _nexthop _route _weight _max_weight _rule

    if is_ipv6_address "$_srcaddr"; then
        _ipv6_flag="-6"
    fi

    while IFS="" read -r _route; do
        if [[ "$_route" =~ [[:space:]]+nexthop ]]; then
            _route=${_route##[[:space:]]}
            # Parse multipath route, using previous _target
            [[ "$_target" == 'default' ]] && continue
            [[ "$_route" =~ .*via.*\ $_netdev ]] || continue

            _weight=$(echo "$_route" | cut -d ' ' -f7)
            if [[ "$_weight" -gt "$_max_weight" ]]; then
                _nexthop=$(echo "$_route" | cut -d ' ' -f3)
                _max_weight=$_weight
                if [[ "x" !=  "x"$_ipv6_flag ]]; then
                    _rule="rd.route=[$_target]:[$_nexthop]:$kdumpnic"
                else
                    _rule="rd.route=$_target:$_nexthop:$kdumpnic"
                fi
            fi
        else
            [[ -n "$_rule" ]] && echo "$_rule"
            _target=$(echo "$_route" | cut -d ' ' -f1)
            _rule="" _max_weight=0 _weight=0
        fi
    done >> "${initdir}/etc/cmdline.d/45route-static.conf"\
        <<< "$(/sbin/ip $_ipv6_flag route show)"

    [[ -n $_rule ]] && echo "$_rule" >> "${initdir}/etc/cmdline.d/45route-static.conf"
}

kdump_get_mac_addr() {
    cat "/sys/class/net/$1/address"
}

#Bonding or team master modifies the mac address
#of its slaves, we should use perm address
kdump_get_perm_addr() {
    local addr=$(ethtool -P "$1" | sed -e 's/Permanent address: //')
    if [[ -z "$addr" ]] || [[ "$addr" = "00:00:00:00:00:00" ]]
    then
        derror "Can't get the permanent address of $1"
    else
        echo "$addr"
    fi
}

# Prefix kernel assigned names with "kdump-". EX: eth0 -> kdump-eth0
# Because kernel assigned names are not persistent between 1st and 2nd
# kernel. We could probably end up with eth0 being eth1, eth0 being
# eth1, and naming conflict happens.
kdump_setup_ifname() {
    local _ifname

    # If ifname already has 'kdump-' prefix, we must be switching from
    # fadump to kdump. Skip prefixing 'kdump-' in this case as adding
    # another prefix may truncate the ifname. Since an ifname with
    # 'kdump-' is already persistent, this should be fine.
    if [[ $1 =~ eth* ]] && [[ ! $1 =~ ^kdump-* ]]; then
        _ifname="kdump-$1"
    else
        _ifname="$1"
    fi

    echo "$_ifname"
}

kdump_setup_bridge() {
    local _netdev=$1
    local _brif _dev _mac _kdumpdev
    for _dev in "/sys/class/net/$_netdev/brif/"*; do
        [[ -e $_dev ]] || continue
        _dev=${_dev##*/}
        _kdumpdev=$_dev
        if kdump_is_bond "$_dev"; then
            (kdump_setup_bond "$_dev" "$(get_nmcli_connection_show_cmd_by_ifname "$_dev")")
            if [[ $? != 0 ]]; then
                exit 1
            fi
        elif kdump_is_team "$_dev"; then
            kdump_setup_team "$_dev"
        elif kdump_is_vlan "$_dev"; then
            kdump_setup_vlan "$_dev"
        else
            _mac=$(kdump_get_mac_addr "$_dev")
            _kdumpdev=$(kdump_setup_ifname "$_dev")
            echo -n " ifname=$_kdumpdev:$_mac" >> "${initdir}/etc/cmdline.d/41bridge.conf"
        fi
        _brif+="$_kdumpdev,"
    done
    echo " bridge=$_netdev:${_brif%,}" >> "${initdir}/etc/cmdline.d/41bridge.conf"
}

# drauct takes bond=<bondname>[:<bondslaves>:[:<options>]] syntax to parse
#    bond. For example:
#     bond=bond0:eth0,eth1:mode=balance-rr
kdump_setup_bond() {
    local _netdev="$1"
    local _nm_show_cmd="$2"
    local _dev _mac _slaves _kdumpdev _bondoptions
    for _dev in $(cat "/sys/class/net/$_netdev/bonding/slaves"); do
        _mac=$(kdump_get_perm_addr "$_dev")
        _kdumpdev=$(kdump_setup_ifname "$_dev")
        echo -n " ifname=$_kdumpdev:$_mac" >> "${initdir}/etc/cmdline.d/42bond.conf"
        _slaves+="$_kdumpdev,"
    done
    echo -n " bond=$_netdev:${_slaves%,}" >> "${initdir}/etc/cmdline.d/42bond.conf"

    _bondoptions=$(get_nmcli_value_by_field "$_nm_show_cmd" "bond.options")

    if [[ -z "$_bondoptions" ]]; then
        dwarning "Failed to get bond configuration via nmlci output. Now try sourcing ifcfg script."
        source_ifcfg_file "$_netdev"
        _bondoptions="$(echo "$BONDING_OPTS" | xargs echo | tr " " ",")"
    fi

    if [[ -z "$_bondoptions" ]]; then
        derror "Get empty bond options"
        exit 1
    fi

    echo ":$_bondoptions" >> "${initdir}/etc/cmdline.d/42bond.conf"
}

kdump_setup_team() {
    local _netdev=$1
    local _dev _mac _slaves _kdumpdev
    for _dev in $(teamnl "$_netdev" ports | awk -F':' '{print $2}'); do
        _mac=$(kdump_get_perm_addr "$_dev")
        _kdumpdev=$(kdump_setup_ifname "$_dev")
        echo -n " ifname=$_kdumpdev:$_mac" >> "${initdir}/etc/cmdline.d/44team.conf"
        _slaves+="$_kdumpdev,"
    done
    echo " team=$_netdev:${_slaves%,}" >> "${initdir}/etc/cmdline.d/44team.conf"
    #Buggy version teamdctl outputs to stderr!
    #Try to use the latest version of teamd.
    teamdctl "$_netdev" config dump > "${initdir}/tmp/$$-$_netdev.conf"
    if [[ $? -ne 0 ]]
    then
        derror "teamdctl failed."
        exit 1
    fi
    inst_dir /etc/teamd
    inst_simple "${initdir}/tmp/$$-$_netdev.conf" "/etc/teamd/$_netdev.conf"
    rm -f "${initdir}/tmp/$$-$_netdev.conf"
}

kdump_setup_vlan() {
    local _netdev=$1
    local _phydev="$(awk '/^Device:/{print $2}' /proc/net/vlan/"$_netdev")"
    local _netmac="$(kdump_get_mac_addr "$_phydev")"
    local _kdumpdev

    #Just support vlan over bond and team
    if kdump_is_bridge "$_phydev"; then
        derror "Vlan over bridge is not supported!"
        exit 1
    elif kdump_is_bond "$_phydev"; then
        (kdump_setup_bond "$_phydev" "$(get_nmcli_connection_show_cmd_by_ifname "$_phydev")")
        if [[ $? != 0 ]]; then
            exit 1
        fi
        echo " vlan=$(kdump_setup_ifname "$_netdev"):$_phydev" > "${initdir}/etc/cmdline.d/43vlan.conf"
    else
        _kdumpdev="$(kdump_setup_ifname "$_phydev")"
        echo " vlan=$(kdump_setup_ifname "$_netdev"):$_kdumpdev ifname=$_kdumpdev:$_netmac" > "${initdir}/etc/cmdline.d/43vlan.conf"
    fi
}

# find online znet device
# return ifname (_netdev)
# code reaped from the list_configured function of
# https://github.com/hreinecke/s390-tools/blob/master/zconf/znetconf
find_online_znet_device() {
	local CCWGROUPBUS_DEVICEDIR="/sys/bus/ccwgroup/devices"
	local NETWORK_DEVICES d ifname ONLINE

	[[ ! -d "$CCWGROUPBUS_DEVICEDIR" ]] && return
	NETWORK_DEVICES=$(find $CCWGROUPBUS_DEVICEDIR)
	for d in $NETWORK_DEVICES
	do
		[[ ! -f "$d/online" ]] && continue
		read -r ONLINE < "$d/online"
		if [[ $ONLINE -ne 1 ]]; then
			continue
		fi
		# determine interface name, if there (only for qeth and if
		# device is online)
		if [[ -f $d/if_name ]]
		then
			read -r ifname < "$d/if_name"
		elif [[ -d $d/net ]]
		then
			ifname=$(ls "$d/net/")
		fi
		[[ -n "$ifname" ]] && break
	done
	echo -n "$ifname"
}

# setup s390 znet cmdline
# $1: netdev (ifname)
# $2: nmcli connection show output
kdump_setup_znet() {
    local _netdev="$1"
    local _nmcli_cmd="$2"
    local s390_prefix="802-3-ethernet.s390-"
    local _options=""
    local NETTYPE
    local SUBCHANNELS

    NETTYPE=$(get_nmcli_value_by_field "$_nmcli_cmd" "${s390_prefix}nettype")
    SUBCHANNELS=$(get_nmcli_value_by_field "$_nmcli_cmd" "${s390_prefix}subchannels")
    _options=$(get_nmcli_value_by_field "$_nmcli_cmd" "${s390_prefix}options")

    if [[ -z "$NETTYPE" || -z "$SUBCHANNELS" || -z "$_options" ]]; then
        dwarning "Failed to get znet configuration via nmlci output. Now try sourcing ifcfg script."
        source_ifcfg_file "$_netdev"
        for i in $OPTIONS; do
            _options=${_options},$i
        done
    fi

    if [[ -z "$NETTYPE" || -z "$SUBCHANNELS" || -z "$_options" ]]; then
        exit 1
    fi

    echo "rd.znet=${NETTYPE},${SUBCHANNELS},${_options} rd.znet_ifname=$_netdev:${SUBCHANNELS}" > "${initdir}/etc/cmdline.d/30znet.conf"
}

kdump_get_ip_route()
{
    local _route=$(/sbin/ip -o route get to "$1" 2>&1)
    if [[ $? != 0 ]]; then
        derror "Bad kdump network destination: $1"
        exit 1
    fi
    echo "$_route"
}

kdump_get_ip_route_field()
{
    echo "$1" | sed -n -e "s/^.*\<$2\>\s\+\(\S\+\).*$/\1/p"
}

kdump_get_remote_ip()
{
    local _remote=$(get_remote_host "$1") _remote_temp
    if is_hostname "$_remote"; then
        _remote_temp=$(getent ahosts "$_remote" | grep -v : | head -n 1)
        if [[ -z "$_remote_temp" ]]; then
            _remote_temp=$(getent ahosts "$_remote" | head -n 1)
        fi
        _remote=$(echo "$_remote_temp" | awk '{print $1}')
    fi
    echo "$_remote"
}

# Setup dracut to bring up network interface that enable
# initramfs accessing giving destination
# $1: destination host
kdump_install_net() {
    local _destaddr _srcaddr _route _netdev _nm_show_cmd kdumpnic
    local _static _proto _ip_conf _ip_opts _ifname_opts
    local _znet_netdev _nm_show_cmd_znet

    _destaddr=$(kdump_get_remote_ip "$1")
    _route=$(kdump_get_ip_route "$_destaddr")
    _srcaddr=$(kdump_get_ip_route_field "$_route" "src")
    _netdev=$(kdump_get_ip_route_field "$_route" "dev")
    _nm_show_cmd=$(get_nmcli_connection_show_cmd_by_ifname "$_netdev")
    _netmac=$(kdump_get_mac_addr "$_netdev")
    kdumpnic=$(kdump_setup_ifname "$_netdev")

    _znet_netdev=$(find_online_znet_device)
    if [[ -n "$_znet_netdev" ]]; then
        _nm_show_cmd_znet=$(get_nmcli_connection_show_cmd_by_ifname "$_znet_netdev")
        (kdump_setup_znet "$_znet_netdev" "$_nm_show_cmd_znet")
        if [[ $? != 0 ]]; then
            derror "Failed to set up znet"
            exit 1
        fi
    fi

    _static=$(kdump_static_ip "$_netdev" "$_srcaddr" "$kdumpnic")
    if [[ -n "$_static" ]]; then
        _proto=none
    elif is_ipv6_address "$_srcaddr"; then
        _proto=auto6
    else
        _proto=dhcp
    fi

    _ip_conf="${initdir}/etc/cmdline.d/40ip.conf"
    _ip_opts=" ip=${_static}$kdumpnic:${_proto}"

    # dracut doesn't allow duplicated configuration for same NIC, even they're exactly the same.
    # so we have to avoid adding duplicates
    # We should also check /proc/cmdline for existing ip=xx arg.
    # For example, iscsi boot will specify ip=xxx arg in cmdline.
    if [[ ! -f $_ip_conf ]] || ! grep -q "$_ip_opts" "$_ip_conf" &&\
        ! grep -q "ip=[^[:space:]]*$_netdev" /proc/cmdline; then
        echo "$_ip_opts" >> "$_ip_conf"
    fi

    if kdump_is_bridge "$_netdev"; then
        kdump_setup_bridge "$_netdev"
    elif kdump_is_bond "$_netdev"; then
        (kdump_setup_bond "$_netdev" "$_nm_show_cmd")
        if [[ $? != 0 ]]; then
            exit 1
        fi
    elif kdump_is_team "$_netdev"; then
        kdump_setup_team "$_netdev"
    elif kdump_is_vlan "$_netdev"; then
        kdump_setup_vlan "$_netdev"
    else
        _ifname_opts=" ifname=$kdumpnic:$_netmac"
        echo "$_ifname_opts" >> "$_ip_conf"
    fi

    kdump_setup_dns "$_netdev" "$_nm_show_cmd"

    if [[ ! -f ${initdir}/etc/cmdline.d/50neednet.conf ]]; then
        # network-manager module needs this parameter
        echo "rd.neednet" >> "${initdir}/etc/cmdline.d/50neednet.conf"
    fi

    # Save netdev used for kdump as cmdline
    # Whoever calling kdump_install_net() is setting up the default gateway,
    # ie. bootdev/kdumpnic. So don't override the setting if calling
    # kdump_install_net() for another time. For example, after setting eth0 as
    # the default gate way for network dump, eth1 in the fence kdump path will
    # call kdump_install_net again and we don't want eth1 to be the default
    # gateway.
    if [[ ! -f ${initdir}/etc/cmdline.d/60kdumpnic.conf ]] &&
       [[ ! -f ${initdir}/etc/cmdline.d/70bootdev.conf ]]; then
        echo "kdumpnic=$kdumpnic" > "${initdir}/etc/cmdline.d/60kdumpnic.conf"
        echo "bootdev=$kdumpnic" > "${initdir}/etc/cmdline.d/70bootdev.conf"
    fi
}

# install etc/kdump/pre.d and /etc/kdump/post.d
kdump_install_pre_post_conf() {
    if [[ -d /etc/kdump/pre.d ]]; then
        for file in /etc/kdump/pre.d/*; do
            if [[ -x "$file" ]]; then
                dracut_install "$file"
            elif [[ $file != "/etc/kdump/pre.d/*" ]]; then
               echo "$file is not executable"
            fi
        done
    fi

    if [[ -d /etc/kdump/post.d ]]; then
        for file in /etc/kdump/post.d/*; do
            if [[ -x "$file" ]]; then
                dracut_install "$file"
            elif [[ $file != "/etc/kdump/post.d/*" ]]; then
                echo "$file is not executable"
            fi
        done
    fi
}

default_dump_target_install_conf()
{
    local _target _fstype
    local _mntpoint _save_path

    is_user_configured_dump_target && return

    _save_path=$(get_bind_mount_source "$(get_save_path)")
    _target=$(get_target_from_path "$_save_path")
    _mntpoint=$(get_mntpoint_from_target "$_target")

    _fstype=$(get_fs_type_from_target "$_target")
    if is_fs_type_nfs "$_fstype"; then
        kdump_install_net "$_target"
        _fstype="nfs"
    else
        _target=$(kdump_get_persistent_dev "$_target")
    fi

    echo "$_fstype $_target" >> "${initdir}/tmp/$$-kdump.conf"

    # don't touch the path under root mount
    if [[ "$_mntpoint" != "/" ]]; then
        _save_path=${_save_path##"$_mntpoint"}
    fi

    #erase the old path line, then insert the parsed path
    sed -i "/^path/d" "${initdir}/tmp/$$-kdump.conf"
    echo "path $_save_path" >> "${initdir}/tmp/$$-kdump.conf"
}

#install kdump.conf and what user specifies in kdump.conf
kdump_install_conf() {
    local _opt _val _pdev

    kdump_read_conf > "${initdir}/tmp/$$-kdump.conf"

    while read -r _opt _val;
    do
        # remove inline comments after the end of a directive.
        case "$_opt" in
        raw)
            _pdev=$(persistent_policy="by-id" kdump_get_persistent_dev "$_val")
            sed -i -e "s#^${_opt}[[:space:]]\+$_val#$_opt $_pdev#" "${initdir}/tmp/$$-kdump.conf"
            ;;
        ext[234]|xfs|btrfs|minix)
            _pdev=$(kdump_get_persistent_dev "$_val")
            sed -i -e "s#^${_opt}[[:space:]]\+$_val#$_opt $_pdev#" "${initdir}/tmp/$$-kdump.conf"
            ;;
        ssh|nfs)
            kdump_install_net "$_val"
            ;;
        dracut_args)
            if [[ $(get_dracut_args_fstype "$_val") = nfs* ]] ; then
                kdump_install_net "$(get_dracut_args_target "$_val")"
            fi
            ;;
        kdump_pre|kdump_post|extra_bins)
            dracut_install "$_val"
            ;;
        core_collector)
            dracut_install "${_val%%[[:blank:]]*}"
            ;;
        esac
    done <<< "$(kdump_read_conf)"

    kdump_install_pre_post_conf

    default_dump_target_install_conf

    kdump_configure_fence_kdump  "${initdir}/tmp/$$-kdump.conf"
    inst "${initdir}/tmp/$$-kdump.conf" "/etc/kdump.conf"
    rm -f "${initdir}/tmp/$$-kdump.conf"
}

# Default sysctl parameters should suffice for kdump kernel.
# Remove custom configurations sysctl.conf & sysctl.d/*
remove_sysctl_conf() {

    # As custom configurations like vm.min_free_kbytes can lead
    # to OOM issues in kdump kernel, avoid them
    rm -f "${initdir}/etc/sysctl.conf"
    rm -rf "${initdir}/etc/sysctl.d"
    rm -rf "${initdir}/run/sysctl.d"
    rm -rf "${initdir}/usr/lib/sysctl.d"
}

kdump_iscsi_get_rec_val() {

    local result

    # The open-iscsi 742 release changed to using flat files in
    # /var/lib/iscsi.

    result=$(/sbin/iscsiadm --show -m session -r "$1" | grep "^${2} = ")
    result=${result##* = }
    echo "$result"
}

kdump_get_iscsi_initiator() {
    local _initiator
    local initiator_conf="/etc/iscsi/initiatorname.iscsi"

    [[ -f "$initiator_conf" ]] || return 1

    while read -r _initiator; do
        [[ -z "${_initiator%%#*}" ]] && continue # Skip comment lines

        case $_initiator in
            InitiatorName=*)
                initiator=${_initiator#InitiatorName=}
                echo "rd.iscsi.initiator=${initiator}"
                return 0;;
            *) ;;
        esac
    done < ${initiator_conf}

    return 1
}

# Figure out iBFT session according to session type
is_ibft() {
    [[ "$(kdump_iscsi_get_rec_val "$1" "node.discovery_type")" = fw ]]
}

kdump_setup_iscsi_device() {
    local path=$1
    local tgt_name; local tgt_ipaddr;
    local username; local password; local userpwd_str;
    local username_in; local password_in; local userpwd_in_str;
    local netroot_str ; local initiator_str;
    local netroot_conf="${initdir}/etc/cmdline.d/50iscsi.conf"
    local initiator_conf="/etc/iscsi/initiatorname.iscsi"

    dinfo "Found iscsi component $1"

    # Check once before getting explicit values, so we can bail out early,
    # e.g. in case of pure-hardware(all-offload) iscsi.
    if ! /sbin/iscsiadm -m session -r "$path" &>/dev/null ; then
        return 1
    fi

    if is_ibft "$path"; then
        return
    fi

    # Remove software iscsi cmdline generated by 95iscsi,
    # and let kdump regenerate here.
    rm -f "${initdir}/etc/cmdline.d/95iscsi.conf"

    tgt_name=$(kdump_iscsi_get_rec_val "$path" "node.name")
    tgt_ipaddr=$(kdump_iscsi_get_rec_val "$path" "node.conn\[0\].address")

    # get and set username and password details
    username=$(kdump_iscsi_get_rec_val "$path" "node.session.auth.username")
    [[ "$username" == "<empty>" ]] && username=""
    password=$(kdump_iscsi_get_rec_val "$path" "node.session.auth.password")
    [[ "$password" == "<empty>" ]] && password=""
    username_in=$(kdump_iscsi_get_rec_val "$path" "node.session.auth.username_in")
    [[ -n "$username" ]] && userpwd_str="$username:$password"

    # get and set incoming username and password details
    [[ "$username_in" == "<empty>" ]] && username_in=""
    password_in=$(kdump_iscsi_get_rec_val "$path" "node.session.auth.password_in")
    [[ "$password_in" == "<empty>" ]] && password_in=""

    [[ -n "$username_in" ]] && userpwd_in_str=":$username_in:$password_in"

    kdump_install_net "$tgt_ipaddr"

    # prepare netroot= command line
    # FIXME: Do we need to parse and set other parameters like protocol, port
    #        iscsi_iface_name, netdev_name, LUN etc.

    if is_ipv6_address "$tgt_ipaddr"; then
        tgt_ipaddr="[$tgt_ipaddr]"
    fi
    netroot_str="netroot=iscsi:${userpwd_str}${userpwd_in_str}@$tgt_ipaddr::::$tgt_name"

    [[ -f $netroot_conf ]] || touch "$netroot_conf"

    # If netroot target does not exist already, append.
    if ! grep -q "$netroot_str" "$netroot_conf"; then
         echo "$netroot_str" >> "$netroot_conf"
         dinfo "Appended $netroot_str to $netroot_conf"
    fi

    # Setup initator
    initiator_str=$(kdump_get_iscsi_initiator)
    [[ $? -ne "0" ]] && derror "Failed to get initiator name" && return 1

    # If initiator details do not exist already, append.
    if ! grep -q "$initiator_str" "$netroot_conf"; then
         echo "$initiator_str" >> "$netroot_conf"
         dinfo "Appended $initiator_str to $netroot_conf"
    fi
}

kdump_check_iscsi_targets () {
    # If our prerequisites are not met, fail anyways.
    type -P iscsistart >/dev/null || return 1

    kdump_check_setup_iscsi() (
        local _dev
        _dev=$1

        [[ -L /sys/dev/block/$_dev ]] || return
        cd "$(readlink -f "/sys/dev/block/$_dev")" || return 1
        until [[ -d sys || -d iscsi_session ]]; do
            cd ..
        done
        [[ -d iscsi_session ]] && kdump_setup_iscsi_device "$PWD"
    )

    [[ $hostonly ]] || [[ $mount_needs ]] && {
        for_each_host_dev_and_slaves_all kdump_check_setup_iscsi
    }
}

# hostname -a is deprecated, do it by ourself
get_alias() {
    local ips
    local entries
    local alias_set

    ips=$(hostname -I)
    for ip in $ips
    do
            # in /etc/hosts, alias can come at the 2nd column
            entries=$(grep "$ip" /etc/hosts | awk '{ $1=""; print $0 }')
            if [[ $? -eq 0 ]]; then
                    alias_set="$alias_set $entries"
            fi
    done

    echo "$alias_set"
}

is_localhost() {
    local hostnames=$(hostname -A)
    local shortnames=$(hostname -A -s)
    local aliasname=$(get_alias)
    local nodename=$1

    hostnames="$hostnames $shortnames $aliasname"

    for name in ${hostnames}; do
        if [[ "$name" == "$nodename" ]]; then
            return 0
        fi
    done
    return 1
}

# retrieves fence_kdump nodes from Pacemaker cluster configuration
get_pcs_fence_kdump_nodes() {
    local nodes

    pcs cluster sync > /dev/null 2>&1 && pcs cluster cib-upgrade > /dev/null 2>&1
    # get cluster nodes from cluster cib, get interface and ip address
    nodelist=$(pcs cluster cib | xmllint --xpath "/cib/status/node_state/@uname" -)

    # nodelist is formed as 'uname="node1" uname="node2" ... uname="nodeX"'
    # we need to convert each to node1, node2 ... nodeX in each iteration
    for node in ${nodelist}; do
        # convert $node from 'uname="nodeX"' to 'nodeX'
        eval "$node"
        nodename="$uname"
        # Skip its own node name
        if is_localhost "$nodename"; then
            continue
        fi
        nodes="$nodes $nodename"
    done

    echo "$nodes"
}

# retrieves fence_kdump args from config file
get_pcs_fence_kdump_args() {
    if [[ -f $FENCE_KDUMP_CONFIG_FILE ]]; then
        . "$FENCE_KDUMP_CONFIG_FILE"
        echo "$FENCE_KDUMP_OPTS"
    fi
}

get_generic_fence_kdump_nodes() {
    local filtered
    local nodes

    nodes=$(kdump_get_conf_val "fence_kdump_nodes")
    for node in ${nodes}; do
        # Skip its own node name
        if is_localhost "$node"; then
            continue
        fi
        filtered="$filtered $node"
    done
    echo "$filtered"
}

# setup fence_kdump in cluster
# setup proper network and install needed files
kdump_configure_fence_kdump () {
    local kdump_cfg_file=$1
    local nodes
    local args

    if is_generic_fence_kdump; then
        nodes=$(get_generic_fence_kdump_nodes)

    elif is_pcs_fence_kdump; then
        nodes=$(get_pcs_fence_kdump_nodes)

        # set appropriate options in kdump.conf
        echo "fence_kdump_nodes $nodes" >> "${kdump_cfg_file}"

        args=$(get_pcs_fence_kdump_args)
        if [[ -n "$args" ]]; then
            echo "fence_kdump_args $args" >> "${kdump_cfg_file}"
        fi

    else
        # fence_kdump not configured
        return 1
    fi

    # setup network for each node
    for node in ${nodes}; do
        kdump_install_net "$node"
    done

    dracut_install /etc/hosts
    dracut_install /etc/nsswitch.conf
    dracut_install "$FENCE_KDUMP_SEND"
}

# Install a random seed used to feed /dev/urandom
# By the time kdump service starts, /dev/uramdom is already fed by systemd
kdump_install_random_seed() {
    local poolsize

    poolsize=$(</proc/sys/kernel/random/poolsize)

    if [[ ! -d "${initdir}/var/lib/" ]]; then
        mkdir -p "${initdir}/var/lib/"
    fi

    dd if=/dev/urandom of="${initdir}/var/lib/random-seed" \
       bs="$poolsize" count=1 2> /dev/null
}

kdump_install_systemd_conf() {
    # Kdump turns out to require longer default systemd mount timeout
    # than 1st kernel(90s by default), we use default 300s for kdump.
    grep -r "^[[:space:]]*DefaultTimeoutStartSec=" "${initdir}/etc/systemd/system.conf"* &>/dev/null
    if [[ $? -ne 0 ]]; then
        mkdir -p "${initdir}/etc/systemd/system.conf.d"
        echo "[Manager]" > "${initdir}/etc/systemd/system.conf.d/kdump.conf"
        echo "DefaultTimeoutStartSec=300s" >> "${initdir}/etc/systemd/system.conf.d/kdump.conf"
    fi

    # Forward logs to console directly, and don't read Kmsg, this avoids
    # unneccessary memory consumption and make console output more useful.
    # Only do so for non fadump image.
    mkdir -p "${initdir}/etc/systemd/journald.conf.d"
    echo "[Journal]" > "${initdir}/etc/systemd/journald.conf.d/kdump.conf"
    echo "Storage=volatile" >> "${initdir}/etc/systemd/journald.conf.d/kdump.conf"
    echo "ReadKMsg=no" >> "${initdir}/etc/systemd/journald.conf.d/kdump.conf"
    echo "ForwardToConsole=yes" >> "${initdir}/etc/systemd/journald.conf.d/kdump.conf"
}

install() {
    kdump_module_init
    kdump_install_conf
    remove_sysctl_conf

    if is_ssh_dump_target; then
        kdump_install_random_seed
    fi
    dracut_install -o /etc/adjtime /etc/localtime
    inst "$moddir/monitor_dd_progress" "/kdumpscripts/monitor_dd_progress"
    chmod +x "${initdir}/kdumpscripts/monitor_dd_progress"
    inst "/bin/dd" "/bin/dd"
    inst "/bin/tail" "/bin/tail"
    inst "/bin/date" "/bin/date"
    inst "/bin/sync" "/bin/sync"
    inst "/bin/cut" "/bin/cut"
    inst "/bin/head" "/bin/head"
    inst "/bin/awk" "/bin/awk"
    inst "/bin/sed" "/bin/sed"
    inst "/sbin/makedumpfile" "/sbin/makedumpfile"
    inst "/sbin/vmcore-dmesg" "/sbin/vmcore-dmesg"
    inst "/usr/bin/printf" "/sbin/printf"
    inst "/usr/bin/logger" "/sbin/logger"
    inst "/usr/bin/chmod" "/sbin/chmod"
    inst "/lib/kdump/kdump-lib.sh" "/lib/kdump-lib.sh"
    inst "/lib/kdump/kdump-lib-initramfs.sh" "/lib/kdump-lib-initramfs.sh"
    inst "/lib/kdump/kdump-logger.sh" "/lib/kdump-logger.sh"
    inst "$moddir/kdump.sh" "/usr/bin/kdump.sh"
    inst "$moddir/kdump-capture.service" "$systemdsystemunitdir/kdump-capture.service"
    systemctl -q --root "$initdir" add-wants initrd.target kdump-capture.service
    inst "$moddir/kdump-error-handler.sh" "/usr/bin/kdump-error-handler.sh"
    # Replace existing emergency service and emergency target
    cp "$moddir/kdump-emergency.service" "$initdir/$systemdsystemunitdir/emergency.service"
    cp "$moddir/kdump-emergency.target" "$initdir/$systemdsystemunitdir/emergency.target"
    # Also redirect dracut-emergency to kdump error handler
    ln_r "$systemdsystemunitdir/emergency.service" "$systemdsystemunitdir/dracut-emergency.service"

    # Check for all the devices and if any device is iscsi, bring up iscsi
    # target. Ideally all this should be pushed into dracut iscsi module
    # at some point of time.
    kdump_check_iscsi_targets

    kdump_install_systemd_conf

    # nfs/ssh dump will need to get host ip in second kernel and need to call 'ip' tool, see get_host_ip for more detail
    if is_nfs_dump_target || is_ssh_dump_target; then
        inst "ip"
    fi

    # For the lvm type target under kdump, in /etc/lvm/lvm.conf we can
    # safely replace "reserved_memory=XXXX"(default value is 8192) with
    # "reserved_memory=1024" to lower memory pressure under kdump. We do
    # it unconditionally here, if "/etc/lvm/lvm.conf" doesn't exist, it
    # actually does nothing.
    sed -i -e \
      's/\(^[[:space:]]*reserved_memory[[:space:]]*=\)[[:space:]]*[[:digit:]]*/\1 1024/' \
      "${initdir}/etc/lvm/lvm.conf" &>/dev/null

    # Save more memory by dropping switch root capability
    dracut_no_switch_root
}