xref: /openbsd/distrib/miniroot/install.sub (revision 097a140d)

#!/bin/ksh
#	$OpenBSD: install.sub,v 1.1163 2021/03/19 23:52:55 kn Exp $
#
# Copyright (c) 1997-2015 Todd Miller, Theo de Raadt, Ken Westerback
# Copyright (c) 2015, Robert Peichaer <rpe@openbsd.org>
#
# 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 THE AUTHOR ``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 THE AUTHOR 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.
#
# Copyright (c) 1996 The NetBSD Foundation, Inc.
# All rights reserved.
#
# This code is derived from software contributed to The NetBSD Foundation
# by Jason R. Thorpe.
#
# 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 THE NETBSD FOUNDATION, INC. 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 THE REGENTS 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.
#

# OpenBSD install/upgrade script common subroutines and initialization code

# ------------------------------------------------------------------------------
# Misc functions
# ------------------------------------------------------------------------------

# Print error message to stderr and exit the script.
err_exit() {
	print -u2 -- "$*"
	exit 1
}

# Show usage of the installer script and exit.
usage() {
	err_exit "usage: ${0##*/} [-ax] [-f filename] [-m install | upgrade]"
}

# Wait for the ftp(1) process started in start_cgiinfo() to end and extract
# various informations from the ftplist.cgi output.
wait_cgiinfo() {
	local _l _s _key _val

	wait "$CGIPID" 2>/dev/null

	# Ensure, there is actual data to extract info from.
	[[ -s $CGI_INFO ]] || return

	# Extract the list of mirror servers.
	sed -En 's,^https?://([[A-Za-z0-9:_][]A-Za-z0-9:._-]*),\1,p' \
		$CGI_INFO >$HTTP_LIST 2>/dev/null

	# Extract the previously selected mirror server (first entry in the
	# ftplist.cgi output, if that has no location info).
	read -r -- _s _l <$HTTP_LIST
	[[ -z $_l ]] && : ${HTTP_SERVER:=${_s%%/*}}

	# Extract the previously used install method, timezone information
	# and a reference timestamp.
	while IFS='=' read -r -- _key _val; do
		case $_key=$_val in
		method=+([a-z])*([0-9]))	CGI_METHOD=$_val;;
		TIME=+([0-9]))			CGI_TIME=$_val;;
		TZ=+([-_/+[:alnum:]]))		CGI_TZ=$_val;;
		esac
	done <$CGI_INFO
}


# ------------------------------------------------------------------------------
# Utils functions
# ------------------------------------------------------------------------------

# Sort and print unique list of provided arguments.
bsort() {
	local _a=$1 _b _l

	(($#)) && shift || return

	for _b; do
		[[ $_a == "$_b" ]] && continue
		if [[ $_a > $_b ]]; then
			_l="$_a $_l" _a=$_b
		else
			_l="$_b $_l"
		fi
	done

	# Output the smallest value found.
	(($#)) && echo -n "$_a " || echo -n "$_a"

	# Sort remaining values.
	bsort $_l
}

# Test the first argument against the remaining ones, return success on a match.
isin() {
	local _a=$1 _b

	shift
	for _b; do
		[[ $_a == "$_b" ]] && return 0
	done
	return 1
}

# Add first argument to list formed by the remaining arguments.
# Adds to the tail if the element does not already exist.
addel() {
	local _a=$1

	shift
	isin "$_a" $* && echo -n "$*" || echo -n "${*:+$* }$_a"
}

# Remove all occurrences of first argument from list formed by the remaining
# arguments.
rmel() {
	local _a=$1 _b _c

	shift
	for _b; do
		[[ $_a != "$_b" ]] && _c="${_c:+$_c }$_b"
	done
	echo -n "$_c"
}

# If possible, print the timestamp received from the ftplist.cgi output,
# adjusted with the time elapsed since it was received.
http_time() {
	local _sec=$(cat $HTTP_SEC 2>/dev/null)

	[[ -n $_sec && -n $CGI_TIME ]] &&
		echo $((CGI_TIME + SECONDS - _sec))
}

# Prints the supplied parameters properly escaped for future sh/ksh parsing.
# Quotes are added if needed, so you should not do that yourself.
quote() (
	# Since this is a subshell we won't pollute the calling namespace.
	for _a; do
		alias Q=$_a; _a=$(alias Q); print -rn -- " ${_a#Q=}"
	done | sed '1s/ //'
	echo
)

# Show a list of ordered arguments (read line by line from stdin) in column
# output using ls.
show_cols() {
	local _l _cdir=/tmp/i/cdir _clist

	mkdir -p $_cdir
	rm -rf -- $_cdir/*
	while read _l; do
		[[ -n $_l ]] || continue
		mkdir -p /tmp/i/cdir/"$_l"
		_clist[${#_clist[*]}]="$_l"
	done
	(cd $_cdir; ls -Cdf "${_clist[@]}")
	rm -rf -- $_cdir
}

# Echo file $1 to stdout. Skip comment lines. Strip leading and trailing
# whitespace if IFS is set.
stripcom() {
	local _file=$1 _line

	[[ -f $_file ]] || return

	set -o noglob
	while read _line; do
		[[ -n ${_line%%#*} ]] && echo $_line
	done <$_file
	set +o noglob
}

# Create a temporary directory based on the supplied directory name prefix.
tmpdir() {
	local _i=1 _dir

	until _dir="${1?}.$_i.$RANDOM" && mkdir -- "$_dir" 2>/dev/null; do
		((++_i < 10000)) || return 1
	done
	echo "$_dir"
}

# Generate unique filename based on the supplied filename $1.
unique_filename() {
	local _fn=$1 _ufn

	while _ufn=${_fn}.$RANDOM && [[ -e $_ufn ]]; do done
	print -- "$_ufn"
}

# Let rc.firsttime feed file $1 using $2 as subject to whatever mail system we
# have at hand by then.
prep_root_mail() {
	local _fn=$1 _subject=$2 _ufn

	[[ -s $_fn ]] || return

	_ufn=$(unique_filename /mnt/var/log/${_fn##*/})
	cp $_fn $_ufn
	chmod 600 $_ufn
	_ufn=${_ufn#/mnt}

	cat <<__EOT >>/mnt/etc/rc.firsttime
( /usr/bin/mail -s '$_subject' root <$_ufn && rm $_ufn ) >/dev/null 2>&1 &
__EOT
}

# Examine the contents of the DHCP lease file $1 for a line containing the
# field provided as parameters and return the value of the first field found.
#
# Note that strings are unescaped but not unvis()'d.
lease_value() {
	local _lf=$1 _o

	[[ -s $_lf ]] || return
	shift

	for _o; do
		sed -E \
			-e '/^ *(option )?'"$_o"' (.*);$/!d;s//\2/' \
			-e '/^"(.*)"$/{s//\1/;s/\\(.)/\1/g;};q' "$_lf" \
			| grep ^ && return
	done
}

# Extract one boot's worth of dmesg.
dmesgtail() {
	dmesg | sed -n 'H;/^OpenBSD/h;${g;p;}'
}

# ------------------------------------------------------------------------------
# Device related functions
# ------------------------------------------------------------------------------

# Show device name, info, NAA and size for the provided list of disk devices.
# Create device nodes as needed and cleanup afterwards.
diskinfo() {
	local _d _i _n _s

	for _d; do
		# Extract disk information enclosed in <> from dmesg.
		_i=$(dmesg | sed -n '/^'$_d' at /h;${g;s/^.*<\(.*\)>.*$/\1/p;}')
		_i=${_i##+([[:space:],])}
		_i=${_i%%+([[:space:],])}

		# Extract Network Address Authority information from dmesg.
		_n=$(dmesg | sed -En '/^'$_d' at /h;${g;s/^.* ([a-z0-9]+\.[a-zA-Z0-9_]+)$/\1/p;}')

		# Extract disk size from disklabel output.
		make_dev $_d
		_s=$(disklabel -dpg $_d 2>/dev/null | sed -n '/.*# total bytes: \(.*\)/{s//(\1)/p;}')
		rm -f /dev/{r,}$_d?

		echo "$_d: $_i $_n $_s"
	done
}

# Create devices passed as arguments.
make_dev() {
	[[ -z $(cd /dev && sh MAKEDEV "$@" 2>&1) ]]
}

# Sort and print information from dmesg.boot using sed expression $1.
scan_dmesg() {
	bsort $(sed -n "$1" /var/run/dmesg.boot)
}

# Extract device names from hw.disknames matching sed expression $1.
scan_disknames() {
	local IFS=, _disks=$(sysctl -n hw.disknames)

	bsort $(for _n in $_disks; do echo "${_n%%:*} "; done | sed -n "$1")
}

# Return disk devices found in hw.disknames.
get_dkdevs() {
	echo $(scan_disknames "${MDDKDEVS:-/^[sw]d[0-9][0-9]* /s/ .*//p}")
}

# Return CDROM devices found in hw.disknames.
get_cddevs() {
	echo $(scan_disknames "${MDCDDEVS:-/^cd[0-9][0-9]* /s/ .*//p}")
}

# Return sorted list of disks not in DISKS_DONE which contains disks already
# initialized during installation.
get_dkdevs_uninitialized() {
	local _disks=$(get_dkdevs) _d

	for _d in $DISKS_DONE; do
		_disks=$(rmel "$_d" $_disks)
	done
	bsort $_disks
}

# Return list of valid root disks
get_dkdevs_root() {
	local _disks=$(get_dkdevs) _d

	if [[ $MODE == upgrade ]]; then
		for _d in $_disks; do
			is_rootdisk "$_d" || _disks=$(rmel "$_d" $_disks)
		done
	fi
	echo -n $_disks
}

# Return list of all network devices, optionally limited by parameters to
# ifconfig. Filter out dynamically created network pseudo-devices except vlan.
get_ifs() {
	local _if _if_list=$(rmel vlan $(ifconfig -C))

	for _if in $(ifconfig "$@" 2>/dev/null | sed '/^[a-z]/!d;s/:.*//'); do
		isin "${_if%%+([0-9])}" $_if_list || echo $_if
	done
}

# Return the device name of the disk device $1, which may be a disklabel UID.
get_dkdev_name() {
	local _dev=${1#/dev/} _d

	_dev=${_dev%.[a-p]}
	((${#_dev} < 16)) && _dev=${_dev%[a-p]}
	local IFS=,
	for _d in $(sysctl -n hw.disknames); do
		[[ $_dev == @(${_d%:*}|${_d#*:}) ]] && echo ${_d%:*} && break
	done
}

# Inspect disk $1 if it has a partition-table of type $2 and optionally
# if it has a partition of type $3.
disk_has() {
	local _disk=$1 _pttype=$2 _part=$3 _cmd _p_pttype _p_part

	[[ -n $_disk && -n $_pttype ]] || exit

	# Commands to inspect disk. Default: "fdisk $_disk"
	local _c_hfs="pdisk -l $_disk"
	local _c_sr="bioctl -q $_disk"

	# Patterns for partition-table-types and partition-types.
	local _p_gpt='Usable LBA:'
	local _p_gpt_openbsd='^[ *]...: OpenBSD '
	local _p_gpt_efisys='^[ *]...: EFI Sys '
	local _p_hfs='^Partition map '
	local _p_hfs_openbsd=' OpenBSD OpenBSD '
	local _p_mbr='Signature: 0xAA55'
	local _p_mbr_openbsd='^..: A6 '
	local _p_mbr_dos='^..: 06 '
	local _p_mbr_dos_active='^\*.: 06 '
	local _p_mbr_linux='^..: 83 '
	local _p_sr='OPENBSD, SR'
	local _p_sr_crypto='OPENBSD, SR CRYPTO'

	# Compose command and patterns based on the parameters.
	eval "_cmd=\"\$_c_${_pttype}\""
	eval "_p_pttype=\"\$_p_${_pttype}\""
	eval "_p_part=\"\$_p_${_pttype}_${_part}\""

	# Set the default command if none was defined before.
	_cmd=${_cmd:-fdisk $_disk}

	# Abort in case of undefined patterns.
	[[ -z $_p_pttype ]] && exit
	[[ -n $_part && -z $_p_part ]] && exit

	if [[ -z $_p_part ]]; then
		$_cmd 2>/dev/null | grep -Eq "$_p_pttype"
	else
		$_cmd 2>/dev/null | grep -Eq "$_p_pttype" &&
			$_cmd 2>/dev/null | grep -Eq "$_p_part"
	fi
}

# Handle disklabel auto-layout for the root disk $1 during interactive install
# and autopartitioning during unattended install by asking for and downloading
# autopartitioning template. Write the resulting fstab to $2. Abort unattended
# installation if autopartitioning fails.
disklabel_autolayout() {
	local _disk=$1 _f=$2 _dl=/tmp/i/disklabel.auto _op _qst

	# Skip disklabel auto-layout for any disk except the root disk.
	[[ $_disk != $ROOTDISK ]] && return

	while $AI; do
		ask "URL to autopartitioning template for disklabel?" none
		[[ $resp == none ]] && break
		if ! $FTP_TLS && [[ $resp == https://* ]]; then
			err_exit "https not supported on this platform."
		fi
		echo "Fetching $resp"
		if unpriv ftp -Vo - "$resp" >$_dl && [[ -s $_dl ]]; then
			disklabel -T $_dl -F $_f -w -A $_disk && return
			err_exit "Autopartitioning failed."
		else
			err_exit "No autopartitioning template found."
		fi
	done

	_qst="Use (A)uto layout, (E)dit auto layout, or create (C)ustom layout?"
	while :; do
		echo "The auto-allocated layout for $_disk is:"
		disklabel -h -A $_disk | egrep "^#  |^  [a-p]:"
		ask "$_qst" a
		case $resp in
		[aA]*)	_op=-w;;
		[eE]*)	_op=-E;;
		[cC]*)	return 0;;
		*)	continue;;
		esac
		disklabel -F $_f $_op -A $_disk
		return
	done
}

# Create a partition table and configure the partition layout for disk $1.
configure_disk() {
	local _disk=$1 _fstab=/tmp/i/fstab.$1 _opt

	make_dev $_disk || return

	# Deal with disklabels, including editing the root disklabel
	# and labeling additional disks. This is machine-dependent since
	# some platforms may not be able to provide this functionality.
	# /tmp/i/fstab.$_disk is created here with 'disklabel -F'.
	rm -f /tmp/i/*.$_disk
	md_prep_disklabel $_disk || return

	# Make sure a '/' mount point exists on the root disk.
	if ! grep -qs ' / ffs ' /tmp/i/fstab.$ROOTDISK; then
		echo "'/' must be configured!"
		$AI && exit 1 || return 1
	fi

	if [[ -f $_fstab ]]; then
		# Avoid duplicate mount points on different disks.
		while read _pp _mp _rest; do
			# Multiple swap partitions are ok.
			if [[ $_mp == none ]]; then
				echo "$_pp $_mp $_rest" >>/tmp/i/fstab
				continue
			fi
			# Non-swap mountpoints must be in only one file.
			if [[ $_fstab != $(grep -l " $_mp " /tmp/i/fstab.*) ]]; then
				_rest=$_disk
				_disk=
				break
			fi
		done <$_fstab

		# Duplicate mountpoint.
		if [[ -z $_disk ]]; then
			# Allow disklabel(8) to read back mountpoint info
			# if it is immediately run against the same disk.
			cat /tmp/i/fstab.$_rest >/etc/fstab
			rm /tmp/i/fstab.$_rest

			set -- $(grep -h " $_mp " /tmp/i/fstab.*[0-9])
			echo "$_pp and $1 can't both be mounted at $_mp."
			$AI && exit 1 || return 1
		fi

		# Add ffs filesystems to list after newfs'ing them. Ignore
		# other filesystems.
		while read _pp _mp _fstype _rest; do
			[[ $_fstype == ffs ]] || continue

			# Default to FFS2 unless otherwise directed.
			if [[ $_mp == / ]]; then
				_opt=${MDROOTFSOPT:--O2}
			else
				_opt=${MDFSOPT:--O2}
			fi
			newfs -q $_opt ${_pp##/dev/}

			# N.B.: '!' is lexically < '/'.
			# That is required for correct sorting of mount points.
			FSENT="$FSENT $_mp!$_pp"
		done <$_fstab
	fi

	return 0
}

# ------------------------------------------------------------------------------
# Functions for the dmesg listener
# ------------------------------------------------------------------------------

# Acquire lock.
lock() {
	while ! mkdir /tmp/i/lock 2>/dev/null && sleep .1; do done
}

# Release lock.
unlock() {
	rm -df /tmp/i/lock 2>/dev/null
}

# Add a trap to kill the dmesg listener co-process on exit of the installer.
retrap() {
	trap 'kill -KILL $CPPID 2>/dev/null; echo; stty echo; exit 0' \
		INT EXIT TERM
}

# Start a listener process looking for dmesg changes which indicates a possible
# plug-in/-out of devices (e.g. usb disks, cdroms, etc.). This is used to abort
# and redraw question prompts, especially in ask_which().
start_dmesg_listener() {
	local _update=/tmp/i/update

	# Ensure the lock is initially released and that no update files exists.
	unlock
	rm -f $_update

	# Do not start the listener if in non-interactive mode.
	$AI && return

	# To ensure that only one dmesg listener instance can be active, run it
	# in a co-process subshell of which there can always only be one active.
	(
	while :; do
		lock
		# The dmesg listener will continuously check for the existence of
		# the update file and sends a signal to the parent process (that
		# is the installer script) if the dmesg output differs from the
		# contents of that file.
		if [[ -e $_update && "$(dmesgtail)" != "$(<$_update)" ]]; then
			dmesgtail >$_update
			kill -TERM 2>/dev/null $$ || exit 1
		fi
		unlock
		sleep .5
	done
	) |&

	# Save the co-process PID in a global variable so it can be used in
	# the retrap() function which adds a trap to kill the co-process on
	# exit of the installer script.
	CPPID=$!
	retrap
}

# ------------------------------------------------------------------------------
# Functions to ask (or auto-answer) questions
# ------------------------------------------------------------------------------

# Log installer questions and answers so that the resulting file can be used as
# response file for an unattended install/upgrade.
log_answers() {
	if [[ -n $1 && -n $2 ]]; then
		print -r -- "${1%%'?'*} = $2" >>/tmp/i/$MODE.resp
	fi
}

# Fetch response file for autoinstall.
get_responsefile() {
	local _rf _if _lf _path _aifile
	export AI_HOSTNAME= AI_MAC= AI_MODE= AI_SERVER=

	[[ -f /auto_upgrade.conf ]] && _rf=/auto_upgrade.conf AI_MODE=upgrade
	[[ -f /auto_install.conf ]] && _rf=/auto_install.conf AI_MODE=install
	[[ -f $_rf ]] && cp $_rf /tmp/ai/ai.$AI_MODE.conf && return

	for _if in ''; do
		[[ -x /sbin/dhclient ]] || break

		# Select a network interface for initial dhcp request.
		# Prefer the interface the system netbooted from.
		set -- $(get_ifs netboot)
		(($# == 0)) && set -- $(get_ifs)
		(($# == 1)) && _if=$1

		# Ask if multiple were found and system was not netbooted.
		while (($# > 1)); do
			ask_which "network interface" \
				"should be used for the initial DHCP request" \
				"$*"
			isin "$resp" $* && _if=$resp && break
		done

		# Issue initial dhcp request via the found interface.
		[[ -n $_if ]] && dhclient $_if || break
		_lf=/var/db/dhclient.leases.$_if

		if ! wait_for_dhcp_info $_if 30; then
			echo "No dhcp address on interface $_if in 30 seconds."
			continue
		fi

		# Extract installer mode and response file path from lease file.
		_aifile=$(lease_value $_lf filename bootfile-name)
		[[ $_aifile == ?(*/)auto_@(install|upgrade) ]] || _aifile=
		_path=${_aifile%auto_@(install|upgrade)}
		AI_MODE=${_aifile##*?(/)auto_}

		# Extract install server ip address from lease file.
		AI_SERVER=$(lease_value $_lf \
			server-name tftp-server-name next-server)

		# Prime hostname with host-name option from lease file.
		AI_HOSTNAME=$(lease_value $_lf host-name)
		hostname "$AI_HOSTNAME"
	done

	# Try to fetch mac-mode.conf, then hostname-mode.conf, and finally
	# mode.conf if install server and mode are known, otherwise tell which
	# one was missing.
	if [[ -n $AI_SERVER && -n $AI_MODE ]]; then
		AI_MAC=$(ifconfig $_if | sed 's/.*lladdr \(.*\)/\1/p;d')
		for _rf in {$AI_MAC-,${AI_HOSTNAME:+$AI_HOSTNAME-,}}$AI_MODE; do
			# Append HTTP_SETDIR as parameter to _url which can be
			# used by the webserver to return dynamically created
			# response files.
			_url="http://$AI_SERVER/$_path$_rf.conf?path=$HTTP_SETDIR"
			echo "Fetching $_url"
			if unpriv ftp -Vo - "$_url" \
				>"/tmp/ai/ai.$AI_MODE.conf" 2>/dev/null; then
				ifconfig $_if delete down 2>/dev/null
				return 0
			fi
		done
	else
		[[ -z $AI_SERVER ]] && echo "Could not determine auto server."
		[[ -z $AI_MODE ]] && echo "Could not determine auto mode."
	fi

	# Ask for url or local path to response file. Provide a default url if
	# server was found in lease file.
	while :; do
		ask "Response file location?" \
			"${AI_SERVER:+http://$AI_SERVER/install.conf}"
		[[ -n $resp ]] && _rf=$resp && break
	done

	# Ask for the installer mode only if auto-detection failed.
	AI_MODE=$(echo "$_rf" | sed -En 's/^.*(install|upgrade).conf$/\1/p')
	while [[ -z $AI_MODE ]]; do
		ask "(I)nstall or (U)pgrade?"
		[[ $resp == [iI]* ]] && AI_MODE=install
		[[ $resp == [uU]* ]] && AI_MODE=upgrade
	done

	echo "Fetching $_rf"
	[[ -f $_rf ]] && _rf="file://$_rf"
	if unpriv ftp -Vo - "$_rf" >"/tmp/ai/ai.$AI_MODE.conf" 2>/dev/null; then
		ifconfig $_if delete down 2>/dev/null
		return 0
	fi
	return 1
}

# Find a response to question $1 in $AI_RESPFILE and return it via $resp.
# Return default answer $2 if provided and none is found in the file.
#
# Move the existing ai.conf file to a tmp file, read from it line by line
# and write a new ai.conf file skipping the line containing the response.
#
# 1) skip empty and comment lines and lines without =
# 2) split question (_key) and answer (_val) at leftmost =
# 3) strip leading/trailing blanks
# 4) compare questions case insensitive (typeset -l)
#
_autorespond() {
	typeset -l _q=$1 _key
	local _def=$2 _l _val

	[[ -f $AI_RESPFILE && -n $_q ]] || return

	mv /tmp/ai/ai.conf /tmp/ai/ai.conf.tmp
	while IFS=' 	' read -r _l; do
		[[ $_l == [!#=]*=?* ]] || continue
		_key=${_l%%*([[:blank:]])=*}
		_val=${_l##*([!=])=*([[:blank:]])}
		[[ $_q == @(|*[[:blank:]])"$_key"@([[:blank:]?]*|) ]] &&
			resp=$_val && cat && return
		print -r " $_l"
	done </tmp/ai/ai.conf.tmp >/tmp/ai/ai.conf
	[[ -n $_def ]] && resp=$_def && return
	err_exit "\nQuestion has no answer in response file: \"$_q\""
}

# Capture user response either by issuing an interactive read or by searching
# the response file and store the response in the global variable $resp.
#
# Optionally present a question $1 and a default answer $2 shown in [].
#
# If the dmesg output is changed while waiting for the interactive response,
# the current read will be aborted and the function will return a non-zero
# value. Normally, the caller function will then reprint any prompt and call
# the function again.
_ask() {
	local _q=$1 _def=$2 _int _redo=0 _pid

	lock; dmesgtail >/tmp/i/update; unlock
	echo -n "${_q:+$_q }${_def:+[$_def] }"
	_autorespond "$_q" "$_def" && echo "$resp" && return
	trap "_int=1" INT
	trap "_redo=1" TERM
	read resp
	lock; rm /tmp/i/update; unlock
	if ((_redo)); then
		stty raw
		stty -raw
	else
		case $resp in
		!)	echo "Type 'exit' to return to install."
			sh
			_redo=1
			;;
		!*)	eval "${resp#?}"
			_redo=1
			;;
		esac
	fi
	retrap
	((_int)) && kill -INT $$
	: ${resp:=$_def}
	return $_redo
}

# Ask for user response to question $1 with an optional default answer $2.
# Write the question and the answer to a logfile.
ask() {

	# Prompt again in case the dmesg listener detected a change.
	while ! _ask "$1" "$2"; do done
	log_answers "$1" "$resp"
}

# Ask the user a yes/no question $1 with 'no' as default answer unless $2 is
# set to 'yes' and insist on 'y', 'yes', 'n' or 'no' as response.
# Return response via $resp as 'y' with exit code 0 or 'n' with exit code 1.
ask_yn() {
	local _q=$1 _a=${2:-no}
	typeset -l _resp

	while :; do
		ask "$_q" "$_a"
		_resp=$resp
		case $_resp in
		y|yes)	resp=y; return 0;;
		n|no)	resp=n; return 1;;
		esac
		echo "'$resp' is not a valid choice."
		$AI && exit 1
	done
}

# Ask for the user to select one value from a list, or 'done'.
# At exit $resp holds selected item, or 'done'.
#
# Parameters:
#
# $1 = name of the list items (disk, cd, etc.)
# $2 = question to ask
# $3 = list of valid choices
# $4 = default choice, if it is not specified use the first item in $3
#
# N.B.! $3 and $4 will be "expanded" using eval, so be sure to escape them
#       if they contain spooky stuff
ask_which() {
	local _name=$1 _query=$2 _list=$3 _def=$4 _dynlist _dyndef _key _q
	_key=$(echo "$_name" | sed 's/[^[:alnum:]]/_/g')

	while :; do
		eval "_dynlist=\"$_list\""
		eval "_dyndef=\"$_def\""

		# Clean away whitespace and determine the default.
		set -o noglob
		set -- $_dyndef; _dyndef="$1"
		set -- $_dynlist; _dynlist="$*"
		set +o noglob
		(($# < 1)) && resp=done && return
		: ${_dyndef:=$1}

		echo "Available ${_name}s are: $_dynlist."
		_q="Which $_name $_query?"
		echo -n "$_q (or 'done') ${_dyndef:+[$_dyndef] }"
		_autorespond "$_q" "${_dyndef-done}" && echo "$resp" \
			|| _ask || continue
		[[ -z $resp ]] && resp="$_dyndef"

		# Quote $resp to prevent user from confusing isin() by
		# entering something like 'a a'.
		if isin "$resp" $_dynlist done; then
			log_answers "$_q" "$resp"
			break
		fi
		echo "'$resp' is not a valid choice."
		$AI && [[ -n $AI_RESPFILE ]] && exit 1
	done
}

# Ask for user response to question $1 with an optional default answer $2
# until a non-empty reply is entered.
ask_until() {
	resp=

	while :; do
		ask "$1" "$2"
		[[ -n $resp ]] && break
		echo "A response is required."
		$AI && exit 1
	done
}

# Capture a user password and save it in $resp, optionally showing prompt $1.
#
# 1) *Don't* allow the '!' options that ask does.
# 2) *Don't* echo input.
# 3) *Don't* interpret "\" as escape character.
# 4) Preserve whitespace in input
#
ask_pass() {
	stty -echo
	IFS= read -r resp?"$1 "
	stty echo
	echo
}

# Ask for a password twice showing prompt $1. Ensure both inputs are identical
# and save it in $_password.
ask_password() {
	local _q=$1

	if $AI; then
		echo -n "$_q "
		_autorespond "$_q"
		echo '<provided>'
		_password=$resp
		return
	fi

	while :; do
		ask_pass "$_q (will not echo)"
		_password=$resp

		ask_pass "$_q (again)"
		[[ $resp == "$_password" ]] && break

		echo "Passwords do not match, try again."
	done
}


# ------------------------------------------------------------------------------
# Support functions for donetconfig()
# ------------------------------------------------------------------------------

# Issue a DHCP request to configure interface $1 and add it to group 'dhcp' to
# later be able to identify DHCP configured interfaces.
dhcp_request() {
	local _if=$1

	echo "lookup file bind" >/etc/resolv.conf.tail

	ifconfig $_if group dhcp >/dev/null 2>&1

	if [[ -x /sbin/dhclient ]]; then
		/sbin/dhclient $_if
	else
		echo "DHCP leases not available during install - no /sbin/dhclient."
	fi

	# Move resolv.conf to where it will be copied to the installed system.
	mv /etc/resolv.conf.tail /tmp/i/resolv.conf.tail
}

# Obtain and output the inet information related to interface $1.
# Outputs:
# <flags>\n<addr> <netmask> <rest of inet line>[\n<more inet lines>]
v4_info() {
	ifconfig $1 inet | sed -n '
		1s/.*flags=.*<\(.*\)>.*/\1/p
		/inet/s/netmask //
		/.inet /s///p'
}

# Wait until dhcp has configured interface $1 within timeout $2 seconds.
wait_for_dhcp_info() {
	local _if=$1 _secs=$2

	# Wait until $_if has a V4 address.
	while (( _secs > 0 )); do
		set -- $(v4_info $_if)
		[[ -n $2 ]] && break
		sleep 1
		(( _secs-- ))
	done

	# Wait until there is a leases file to parse.
	while (( _secs > 0 )); do
		[[ -s /var/db/dhclient.leases.$_if ]] && break
		sleep 1
		(( _secs-- ))
	done

	return $(( _secs <= 0 ))
}

# Convert a netmask in hex format ($1) to dotted decimal format.
hextodec() {
	set -- $(echo ${1#0x} | sed 's/\(..\)/0x\1 /g')
	echo $(($1)).$(($2)).$(($3)).$(($4))
}

# Create an entry in the hosts file using IP address $1 and symbolic name $2.
# Treat $1 as IPv6 address if it contains ':', otherwise as IPv4. If an entry
# with the same name and address family already exists, delete it first.
add_hostent() {
	local _addr=$1 _name=$2 _delim="."

	[[ -z $_addr || -z $_name ]] && return

	[[ $_addr == *:* ]] && _delim=":"
	sed -i "/^[0-9a-fA-F]*[$_delim].*[ 	]$_name\$/d" \
		/tmp/i/hosts 2>/dev/null

	echo "$_addr $_name" >>/tmp/i/hosts
}

# Configure VLAN interface $1 and create the corresponding hostname.if(5) file.
# Ask the user what parent network interface and vnetid to use.
vlan_config() {
	local _if=$1 _hn=/tmp/i/hostname.$1 _hn_vd _vd _vdvi _vdvi_used _vi
	local _sed_vdvi='s/.encap: vnetid ([[:alnum:]]+) parent ([[:alnum:]]+)/\2:\1/p'

	# Use existing parent device and vnetid for this interface as default in
	# case of a restart.
	_vdvi=$(ifconfig $_if 2>/dev/null | sed -En "$_sed_vdvi")
	_vd=${_vdvi%%:*}
	_vi=${_vdvi##*:}

	# Use the vlan interface minor as the default vnetid. If it's 0, set it
	# to 'none' which equals to the default vlan.
	if [[ $_vi == @(|none) ]]; then
		((${_if##vlan} == 0)) && _vi=none || _vi=${_if##vlan}
	fi

	# Use the first non vlan interface as the default parent.
	if [[ $_vd == @(|none) ]]; then
		_vd=$(get_ifs | sed '/^vlan/d' | sed q)
	fi

	ask "Which interface:tag should $_if be on?" "$_vd:$_vi"
	_vd=${resp%%:*}
	_vi=${resp##*:}

	# Ensure that the given parent is an existing (non vlan) interface.
	if ! isin "$_vd" $(get_ifs | sed '/^vlan/d'); then
		echo "Invalid parent interface choice '$_vd'."
		return 1
	fi

	# Get a list of parent:vnetid tuples of all configured vlan interfaces.
	_vdvi_used=$(ifconfig vlan 2>/dev/null | sed -En "$_sed_vdvi")

	# Ensure that the given vnetid is not already configured on the given
	# parent interface.
	for _vdvi in $_vdvi_used; do
		if [[ $_vdvi == $_vd:* && ${_vdvi##*:} == $_vi ]]; then
			echo "vlan tag '$_vi' already used on parent '$_vd'"
			return 1
		fi
	done

	# Further ensure that the given vnetid is 'none', or within 1-4095.
	if [[ $_vi == none ]]; then
		_vi="-vnetid"
	elif (($_vi > 0 && $_vi < 4096)); then
		_vi="vnetid $_vi"
	else
		echo "Invalid vlan tag '$_vi'."
		return 1
	fi

	# Write the config to the hostname.if files and set proper permissions.
	_hn_vd=/tmp/i/hostname.$_vd
	grep -qs "^up" $_hn_vd || echo up >>$_hn_vd
	echo "$_vi parent $_vd" >>$_hn
	chmod 640 $_hn_vd $_hn

	# Bring up the parent interface and configure the vlan interface.
	ifconfig $_vd up
	ifconfig $_if destroy >/dev/null 2>&1
	ifconfig $_if create >/dev/null 2>&1
	ifconfig $_if $_vi parent $_vd
}

# Configure IPv4 on interface $1.
v4_config() {
	local _if=$1 _name=$2 _hn=$3 _addr _mask _newaddr

	# Set default answers based on any existing configuration.
	set -- $(v4_info $_if)
	if [[ -n $2 ]] && ! isin $_if $(get_ifs dhcp); then
		_addr=$2;
		_mask=$(hextodec $3)
	fi

	# Nuke existing inet configuration.
	ifconfig $_if -inet
	ifconfig $_if -group dhcp >/dev/null 2>&1

	while :; do
		ask_until "IPv4 address for $_if? (or 'dhcp' or 'none')" \
			  "${_addr:-dhcp}"
		case $resp in
		none)	return
			;;
		dhcp)	dhcp_request $_if
			echo "dhcp" >>$_hn
			return
			;;
		esac

		_newaddr=$resp

		# Ask for the netmask if the user did not use CIDR notation.
		if [[ $_newaddr == */* ]]; then
			ifconfig $_if $_newaddr up
		else
			ask_until "Netmask for $_if?" "${_mask:-255.255.255.0}"
			ifconfig $_if $_newaddr netmask $resp
		fi

		set -- $(v4_info $_if)
		if [[ -n $2 ]]; then
			echo "inet $2 $3" >>$_hn
			add_hostent "$2" "$_name"
			return
		fi

		$AI && exit 1
	done
}

# Obtain and output the inet6 information related to interface $1.
# <flags>\n<addr> <prefixlen> <rest of inet6 line>[\n<more inet6 lines>]
v6_info() {
	ifconfig $1 inet6 | sed -n '
		1s/.*flags=.*<\(.*\)>.*/\1/p
		/scopeid/d
		/inet6/s/prefixlen //
		/.inet6 /s///p'
}

# Configure an IPv6 default route on interface $1 and preserve that information
# in the /etc/mygate file. Ask the user to either select from a list of default
# router candidates or to enter a router IPv6 address.
v6_defroute() {
	local _if _v6ifs _prompt _resp _routers _dr PS3

	# Only configure a default route if an IPv6 address was manually configured.
	for _if in $(get_ifs); do
		set -- $(v6_info $_if)
		[[ -z $2 || $1 == *AUTOCONF6* ]] || _v6ifs="$_v6ifs $_if"
	done
	[[ -n $_v6ifs ]] || return

	# Start with any existing default routes.
	_routers=$(route -n show -inet6 |
		sed -En 's/^default[[:space:]]+([^[:space:]]+).*/\1 /p')

	# Add more default router canditates by ping6'ing
	# the All-Routers multicast address.
	for _if in $_v6ifs; do
		_resp=$(ping6 -n -c 2 ff02::2%$_if 2>/dev/null |
			sed -En '/^[0-9]+ bytes from /{s///;s/: .*$//p;}')
		for _dr in $_resp; do
			_routers=$(addel $_dr $_routers)
		done
	done

	[[ -n $_routers ]] && _routers=$(bsort $_routers)
	_prompt="IPv6 default router?"

	if $AI; then
		_autorespond "$_prompt (IPv6 address or 'none')" none &&
			echo "$_prompt $resp"
		[[ $resp != none ]] &&
			route -n add -inet6 -host default $resp &&
			echo $resp >>/tmp/i/mygate
	else
		PS3="$_prompt (list #, IPv6 address or 'none') "
		select _resp in none $_routers; do
			[[ $REPLY == none || $_resp == none ]] && break
			[[ -z $_resp ]] && _resp=$REPLY
			# Avoid possible "file exists" errors
			route -n -q delete -inet6 -host default $_resp
			if route -n add -inet6 -host default $_resp; then
				echo $_resp >>/tmp/i/mygate
				break
			fi
		done
	fi
}

# Configure IPv6 interface $1, add hostname $2 to the hosts file,
# create the hostname.if file $3. Ask the user for the IPv6 address
# and prefix length if the address was not specified in CIDR notation,
# unless he chooses 'autoconf'.
v6_config() {
	local _if=$1 _name=$2 _hn=$3 _addr _newaddr _prefixlen

	ifconfig lo0 inet6 >/dev/null 2>&1 || return

	# Preset the default answers by preserving possibly existing
	# configuration from previous runs.
	set -- $(v6_info $_if)
	if [[ $1 == *AUTOCONF6* ]]; then
		_addr=autoconf
	elif [[ -n $2 ]]; then
		_addr=$2
		_prefixlen=$3
	fi

	# Nuke existing inet6 configuration.
	ifconfig $_if -inet6

	while :; do
		ask_until "IPv6 address for $_if? (or 'autoconf' or 'none')" \
			  "${_addr:-none}"
		case $resp in
		none)	return
			;;
		autoconf)
			ifconfig $_if inet6 autoconf up
			echo "inet6 autoconf" >>$_hn
			return
			;;
		esac

		_newaddr=$resp
		if [[ $_newaddr == */* ]]; then
			ifconfig $_if inet6 $_newaddr up
		else
			ask_until "IPv6 prefix length for $_if?" \
				  "${_prefixlen:-64}"
			ifconfig $_if inet6 $_newaddr/$resp up
		fi

		set -- $(v6_info $_if)
		if [[ -n $2 ]]; then
			echo "inet6 $2 $3" >>$_hn
			add_hostent "$2" "$_name"
			return
		fi

		$AI && exit 1
	done
}

# Perform an 802.11 network scan on interface $1 and cache the result a file.
ieee80211_scan() {
	[[ -f $WLANLIST ]] ||
		ifconfig $1 scan |
			sed -n 's/^[[:space:]]*nwid \(.*\) chan [0-9]* bssid \([[:xdigit:]:]*\).*/\1 (\2)/p' >$WLANLIST
	cat $WLANLIST
}

# Configure 802.11 interface $1 and append ifconfig options to hostname.if $2.
# Ask the user for the access point ESSID, the security protocol and a secret.
ieee80211_config() {
	local _if=$1 _hn=$2 _prompt _nwid _haswpa=0 _err

	# Reset 802.11 settings and determine wpa capability.
	ifconfig $_if -nwid -nwkey
	ifconfig $_if -wpa 2>/dev/null && _haswpa=1

	# Empty scan cache.
	rm -f $WLANLIST

	while [[ -z $_nwid ]]; do
		ask_until "Access point? (ESSID, 'any', list# or '?')" "any"
		case "$resp" in
		+([0-9]))
			_nwid=$(ieee80211_scan $_if |
			    sed -n ${resp}'{s/ ([[:xdigit:]:]*)$//p;q;}')
			[[ -z $_nwid ]] && echo "There is no line $resp."
			[[ $_nwid = \"*\" ]] && _nwid=${_nwid#\"} _nwid=${_nwid%\"}
			;;
		\?)	ieee80211_scan $_if | cat -n | more -c
			;;
		*)	_nwid=$resp
			;;
		esac
	done

	# 'any' implies that only open access points are considered.
	if [[ $_nwid != any ]]; then

		_prompt="Security protocol? (O)pen, (W)EP"
		((_haswpa == 1)) && _prompt="$_prompt, WPA-(P)SK"
		while :; do
			ask_until "$_prompt" "O"
			case "$_haswpa-$resp" in
			?-[Oo]) # No further questions
				ifconfig $_if nwid "$_nwid"
				quote nwid "$_nwid" >>$_hn
				break
				;;
			?-[Ww])	ask_until "WEP key? (will echo)"
				# Make sure ifconfig accepts the key.
				if _err=$(ifconfig $_if nwid "$_nwid" nwkey "$resp" 2>&1) &&
					[[ -z $_err ]]; then
					quote nwid "$_nwid" nwkey "$resp" >>$_hn
					break
				fi
				echo "$_err"
				;;
			1-[Pp])	ask_until "WPA passphrase? (will echo)"
				# Make sure ifconfig accepts the key.
				if ifconfig $_if nwid "$_nwid" wpakey "$resp"; then
					quote nwid "$_nwid" wpakey "$resp" >>$_hn
					break
				fi
				;;
			*)	echo "'$resp' is not a valid choice."
				;;
			esac
		done
	fi
}

# Set up IPv4 and IPv6 interface configuration.
configure_ifs() {
	local _first _hn _if _name _p _vi

	# Always need lo0 configured.
	ifconfig lo0 inet 127.0.0.1/8

	# In case of restart, delete previous default gateway config.
	rm -f /tmp/i/mygate

	while :; do
		# Discover last configured vlan interface and increment its
		# minor for the next offered vlan interface.
		_vi=$(get_ifs vlan | sed '$!d;s/^vlan//')
		[[ -n $_vi ]] && ((_vi++))

		ask_which "network interface" "do you wish to configure" \
			"\$(get_ifs) vlan${_vi:-0}" \
			${_p:-'$( (get_ifs netboot; get_ifs) | sed q )'}
		[[ $resp == done ]] && break

		_if=$resp
		_hn=/tmp/i/hostname.$_if
		rm -f $_hn

		# If the offered vlan is chosen, ask the relevant
		# questions and bring it up.
		if [[ $_if == vlan+([0-9]) ]]; then
			vlan_config $_if || continue
		fi

		# Test if it is an 802.11 interface.
		ifconfig $_if 2>/dev/null | grep -q "^[[:space:]]*ieee80211:" &&
			ieee80211_config $_if $_hn

		# First interface configured will use the hostname without
		# asking the user.
		resp=$(hostname -s)
		[[ -n $_first && $_first != $_if ]] &&
			ask "Symbolic (host) name for $_if?" "$resp"
		_name=$resp

		v4_config $_if $_name $_hn
		v6_config $_if $_name $_hn

		if [[ -f $_hn ]]; then
			chmod 640 $_hn
			: ${_first:=$_if}
		fi

		NIFS=$(ls -1 /tmp/i/hostname.* 2>/dev/null | grep -c ^)
		_p=done
	done
}

# Set up IPv4 default route by asking the user for an IPv4 address and preserve
# that information in /etc/mygate. If setting the default route fails, try to
# revert to a possibly existing previous one.
v4_defroute() {
	local _dr _dr_if

	# Only configure a default route if an IPv4 address was configured.
	[[ -n $(ifconfig | sed -n '/[ 	]inet .* broadcast /p') ]] || return

	# Check routing table to see if a default route ($1) already exists
	# and what interface it is connected to ($2).
	set -- $(route -n show -inet |
		sed -En 's/^default +([0-9.]+) .* ([a-z0-9]+) *$/\1 \2/p')
	[[ -n $1 ]] && _dr=$1 _dr_if=$2

	# Don't ask if a default route exits and is handled by dhclient.
	[[ -n $_dr ]] && isin "$_dr_if" $(get_ifs dhcp) && return

	while :; do
		ask_until "Default IPv4 route? (IPv4 address or none)" "$_dr"
		[[ $resp == none ]] && break
		route delete -inet default >/dev/null 2>&1
		if route -n add -inet -host default "$resp"; then
			echo "$resp" >>/tmp/i/mygate
			break
		else
			route -n add -inet -host default $_dr >/dev/null 2>&1
		fi
	done
}

# Extract the domain part from currently configured fully qualified domain name.
# If none is set, use 'my.domain'.
get_fqdn() {
	local _dn

	_dn=$(hostname)
	_dn=${_dn#$(hostname -s)}
	_dn=${_dn#.}

	echo "${_dn:=my.domain}"
}


# ------------------------------------------------------------------------------
# Support functions for install_sets()
# ------------------------------------------------------------------------------

# SANESETS defines the required list of set files for a sane install or upgrade.
# During install_files(), each successfully installed set file is removed from
# DEFAULTSETS. Check if there are SANESETS still in DEFAULTSETS and if they were
# deliberately skipped. If $1 is not defined, ask the user about each skipped
# set file. Care is taken to make sure the return value is correct.
sane_install() {
	local _q=$1 _s

	for _s in $SANESETS; do
		isin "$_s" $DEFAULTSETS || continue
		[[ -n $_q ]] && return 1
		if ! ask_yn "Are you *SURE* your $MODE is complete without '$_s'?"; then
			$AI && exit 1 || return 1
		fi
	done
}

# Show list of available sets $1 and let the user select which sets to install.
# Preselect sets listed in $2 and store the list of selected sets in $resp.
#
# If the list of available sets only contains kernels during an upgrade, assume
# that the user booted into the installer using the currently installed bsd.rd
# and specified a set location pointing to a new release. In this case, only
# show and preselect bsd.rd. By setting UPGRADE_BSDRD the signify key for the
# next release is used to verify the downloaded bsd.rd, the current bsd.rd is
# preserved and no questions about missing sets are asked.
select_sets() {
	local _avail=$1 _selected=$2 _f _action _col=$COLUMNS
	local _bsd_rd _no_sets=true

	if [[ $MODE == upgrade ]]; then
		for _f in $_avail; do
			[[ $_f != bsd* ]] && _no_sets=false
			[[ $_f == bsd.rd* ]] && _bsd_rd=$_f
		done
		$_no_sets && UPGRADE_BSDRD=true _avail=$_bsd_rd _selected=$_bsd_rd
	fi

	# account for 4 spaces added to the sets list
	let COLUMNS=_col-8

	cat <<__EOT

Select sets by entering a set name, a file name pattern or 'all'. De-select
sets by prepending a '-', e.g.: '-game*'. Selected sets are labelled '[X]'.
__EOT
	while :; do
		for _f in $_avail; do
			isin "$_f" $_selected && echo "[X] $_f" || echo "[ ] $_f"
		done | show_cols | sed 's/^/    /'
		ask "Set name(s)? (or 'abort' or 'done')" done

		set -o noglob
		for resp in $resp; do
			case $resp in
			abort)	_selected=; break 2;;
			done)	break 2;;
			-*)	_action=rmel;;
			*)	_action=addel;;
			esac
			resp=${resp#[+-]}
			[[ $resp == all ]] && resp=*

			for _f in $_avail; do
				[[ $_f == $resp ]] &&
					_selected=$($_action $_f $_selected)
			done
		done
	done

	set +o noglob
	COLUMNS=$_col

	resp=$_selected
}

# Run a command ($2+) as unprivileged user ($1).
# Take extra care that after "cmd" no "user" processes exist.
#
# Optionally:
#	- create "file" and chown it to "user"
#	- after "cmd", chown "file" back to root
#
# Usage: do_as user [-f file] cmd
do_as() {
	(( $# >= 2 )) || return

	local _file _rc _user=$1
	shift

	if [[ $1 == -f ]]; then
		_file=$2
		shift 2
	fi

	if [[ -n $_file ]]; then
		>$_file
		chown "$_user" "$_file"
	fi

	doas -u "$_user" "$@"
	_rc=$?

	while doas -u "$_user" kill -9 -1 2>/dev/null; do
		echo "Processes still running for user $_user after: $@"
		sleep 1
	done

	[[ -n $_file ]] && chown root "$_file"

	return $_rc
}

unpriv() {
	do_as _sndio "$@"
}

unpriv2() {
	do_as _file "$@"
}

# Find and list filesystems to store the prefetched sets. Prefer filesystems
# which are not used during extraction with 512M free space. Otherwise search
# any other filesystem that has 2 GB free space to prevent overflow during
# extraction.
prefetcharea_fs_list() {
	local _fs_list

	_fs_list=$( (
		for fs in /mnt/{tmp,home,usr{/local,}}; do
			df -k $fs 2>/dev/null | grep " $fs\$"
		done
		df -k
	) | (
		while read a a a a m m; do
			[[ $m == /mnt/@(tmp|home|usr/@(src,obj,xobj))@(|/*) ]] &&
				((a > 524288)) && echo $m && continue
			[[ $m == /mnt@(|/*) ]] &&
				((a > 524288 * 4)) && echo $m
		done
	) | (
		while read fs; do
			isin "$fs" $list || list="$list${list:+ }$fs"
		done
		echo $list
	) )

	[[ -n $_fs_list ]] && echo $_fs_list || return 1
}

# Install a user-selected subset of the files listed in $2 from the source $1.
# Display an error message for each failed install and ask the user whether to
# continue or not.
install_files() {
	local _src=$1 _files=$2 _f _sets _get_sets _n _col=$COLUMNS _tmpfs \
		_tmpfs_list _tmpsrc _cfile=/tmp/SHA256 _fsrc _unver _t _issue
	local _srclocal=false _unpriv=unpriv

	# Fetch sets from local sources (disk, cdrom, nfs) as root.
	[[ $_src == file://* ]] && _srclocal=true _unpriv=

	# Based on the file list in $_files, create two lists for select_sets().
	# _sets:     the list of files the user can select from
	# _get_sets: the list of files that are shown as pre-selected
	#
	# Sets will be installed in the order given in ALLSETS to ensure proper
	# installation.  So, to minimize user confusion display the sets in the
	# order in which they will be installed.
	for _f in $ALLSETS; do
		isin "$_f" $_files || continue
		_sets=$(addel $_f $_sets)
		isin "$_f" $DEFAULTSETS "site$VERSION-$(hostname -s).tgz" &&
			_get_sets=$(addel $_f $_get_sets)
	done

	if [[ -z $_sets ]]; then
		echo -n "Looked at $_src "
		echo "and found no $OBSD sets.  The set names looked for were:"

		let COLUMNS=_col-8
		for _n in $ALLSETS; do echo $_n; done | show_cols | sed 's/^/    /'
		COLUMNS=$_col

		$AI && exit 1
		echo
		return
	fi

	isin "INSTALL.$ARCH" $_files ||
		ask_yn "INSTALL.$ARCH not found. Use sets found here anyway?" ||
		return

	select_sets "$_sets" "$_get_sets"

	[[ -n $resp ]] || return
	_get_sets=$resp

	# Reorder $_get_sets.
	_get_sets=$(for s in $ALLSETS; do isin "$s" $_get_sets && echo $s; done)

	# Note which sets didn't verify ok.
	_unver=$_get_sets

	# Try to prefetch and control checksum of the set files.
	# Use dummy for loop as combined assignment and do { ... } while(0).
	for _issue in ''; do
		! isin SHA256.sig $_files &&
			_issue="Directory does not contain SHA256.sig" && break

		if ! $_srclocal; then
			! _tmpfs_list=$(prefetcharea_fs_list) &&
				_issue="Cannot determine prefetch area" && break

			for _tmpfs in $_tmpfs_list; do
				# Try to clean up from previous runs, assuming
				# the _tmpfs selection yields the same mount
				# point.
				for _tmpsrc in $_tmpfs/sets.+([0-9]).+([0-9]); do
					[[ -d $_tmpsrc ]] && rm -r $_tmpsrc
				done

				# Create a download directory for the sets and
				# check that the _sndio user can read files from
				# it. Otherwise cleanup and skip the filesystem.
				if _tmpsrc=$(tmpdir "$_tmpfs/sets"); then
					(
					>$_tmpsrc/t &&
					$_unpriv cat $_tmpsrc/t
					) >/dev/null 2>&1 && break ||
						rm -r $_tmpsrc
				fi
			done

			[[ ! -d $_tmpsrc ]] &&
				_issue="Cannot create prefetch area" && break
		fi

		# Cleanup from previous runs.
		rm -f $_cfile $_cfile.sig

		_t=Get/Verify
		$_srclocal && _t='Verifying '

		# Fetch signature file.
		! $_unpriv ftp -D "$_t" -Vmo - "$_src/SHA256.sig" >"$_cfile.sig" &&
			_issue="Cannot fetch SHA256.sig" && break

		# The bsd.rd only download/verify/install assumes the sets
		# location of the next release. So use the right signature file.
		$UPGRADE_BSDRD &&
			PUB_KEY=/mnt/etc/signify/openbsd-$((VERSION + 1))-base.pub

		# Verify signature file with public keys.
		! unpriv -f "$_cfile" \
			signify -Vep $PUB_KEY -x "$_cfile.sig" -m "$_cfile" &&
			_issue="Signature check of SHA256.sig failed" && break

		# Fetch and verify the set files.
		for _f in $_get_sets; do
			$UU && reset_watchdog

			rm -f /tmp/h /tmp/fail

			# Fetch set file and create a checksum by piping through
			# sha256. Create a flag file in case ftp failed. Sets
			# from net are written to the prefetch area, the output
			# of local sets is discarded.
			( $_unpriv ftp -D "$_t" -Vmo - "$_src/$_f" || >/tmp/fail ) |
			( $_srclocal && unpriv2 sha256 >/tmp/h ||
				unpriv2 -f /tmp/h sha256 -ph /tmp/h >"$_tmpsrc/$_f" )

			# Handle failed transfer.
			if [[ -f /tmp/fail ]]; then
				rm -f "$_tmpsrc/$_f"
				if ! ask_yn "Fetching of $_f failed. Continue anyway?"; then
					[[ -d $_tmpsrc ]] && rm -rf "$_tmpsrc"
					$AI && exit 1
					return
				fi
				_unver=$(rmel $_f $_unver)
				_get_sets=$(rmel $_f $_get_sets)
				continue
			fi

			# Verify sets by comparing its checksum with SHA256.
			if fgrep -qx "SHA256 ($_f) = $(</tmp/h)" "$_cfile"; then
				_unver=$(rmel $_f $_unver)
			else
				if ! ask_yn "Checksum test for $_f failed. Continue anyway?"; then
					[[ -d $_tmpsrc ]] && rm -rf "$_tmpsrc"
					$AI && exit 1
					return
				fi
			fi
		done
	done

	[[ -n $_unver ]] && : ${_issue:="Unverified sets:" ${_unver% }}
	if [[ -n $_issue ]] &&
		! ask_yn "$_issue. Continue without verification?"; then
		[[ -d $_tmpsrc ]] && rm -rf "$_tmpsrc"
		$AI && exit 1
		return
	fi

	# We are committed to installing new files.  Attempt to cope with
	# potential space shortage in /usr by deleting a few versioned
	# areas which will be replaced from the new sets
	if [[ $MODE == upgrade ]]; then
		if isin base$VERSION.tgz $_get_sets; then
			rm -f /mnt/usr/share/relink/usr/lib/*
			rm -rf /mnt/usr/lib/libLLVM.so.[012].0
			rm -rf /mnt/usr/libdata/perl5
		fi
		if isin comp$VERSION.tgz $_get_sets; then
			rm -rf /mnt/usr/lib/{gcc-lib,clang}
			rm -rf /mnt/usr/include/g++
		fi
		rm -rf /mnt/var/syspatch/*
	fi

	# Install the set files.
	for _f in $_get_sets; do
		$UU && reset_watchdog
		_fsrc="$_src/$_f"

		# Take the set file from the prefetch area if possible.
		[[ -f $_tmpsrc/$_f ]] && _fsrc="file://$_tmpsrc/$_f"

		# Extract the set files and put the kernel files in place.
		case $_fsrc in
		*.tgz)	$_unpriv ftp -D Installing -Vmo - "$_fsrc" |
				tar -zxphf - -C /mnt &&
			if [[ $_f == ?(x)base*.tgz && $MODE == install ]]; then
				ftp -D Extracting -Vmo - \
				file:///mnt/var/sysmerge/${_f%%base*}etc.tgz |
				tar -zxphf - -C /mnt
			fi
			;;
		*)	# Make a backup of the existing ramdisk kernel in the
			# bsd.rd only download/verify/install case.
			$UPGRADE_BSDRD && [[ $_f == bsd.rd* ]] &&
				cp /mnt/$_f /mnt/$_f.old.$VERSION
			$_unpriv ftp -D Installing -Vmo - "$_fsrc" >"/mnt/$_f"
			;;
		esac
		if (($?)); then
			if ! ask_yn "Installation of $_f failed. Continue anyway?"; then
				[[ -d $_tmpsrc ]] && rm -rf "$_tmpsrc"
				$AI && exit 1
				return
			fi
		else
			# Remove each successfully installed set file from
			# DEFAULTSETS which is checked by sane_sets().
			DEFAULTSETS=$(rmel $_f $DEFAULTSETS)
			# Reset DEFAULTSETS to make sure that sane_sets() does
			# not complain about missing set files in the bsd.rd
			# only download/verify/install case,
			$UPGRADE_BSDRD && DEFAULTSETS=
		fi
		[[ -d $_tmpsrc ]] && rm -f "$_tmpsrc/$_f"
	done
	[[ -d $_tmpsrc ]] && rm -rf "$_tmpsrc" || true

	# Keep SHA256 from installed sets for sysupgrade(8).
	if [[ -f $_cfile ]]; then
		cp $_cfile /mnt/var/db/installed.SHA256
	elif $_srclocal && [[ -f ${_src#file://}/SHA256 ]]; then
		cp ${_src#file://}/SHA256 /mnt/var/db/installed.SHA256
	fi

	$UU && reset_watchdog
}

# Fetch install sets from an HTTP server possibly using a proxy.
install_http() {
	local _d _f _flist _file_list _prompt _tls _http_proto _url_base
	local _idx=/tmp/i/index.txt _sha=/tmp/i/SHA256 _sig=/tmp/i/SHA256.sig
	local _iu_url _iu_srv _iu_dir _mirror_url _mirror_srv _mirror_dir
	local _ftp_stdout=/tmp/i/ftpstdout _rurl_base

	# N.B.: Don't make INSTALL_MIRROR a local variable! It preserves the
	# mirror information if install_http() is called multiple times with
	# mirror and local servers. That ensures that the mirror server ends
	# up in /etc/installurl file if one of the servers is not a mirror.

	# N.B.: 'http_proxy' is an environment variable used by ftp(1).
	# DON'T change the name or case!
	ask "HTTP proxy URL? (e.g. 'http://proxy:8080', or 'none')" \
		"${http_proxy:-none}"
	unset http_proxy
	[[ $resp == none ]] || export http_proxy=$resp

	# If the mirror server listfile download failed, inform the user and
	# show a reduced prompt.
	if [[ -s $HTTP_LIST ]]; then
		_prompt="HTTP Server? (hostname, list#, 'done' or '?')"
	else
		echo "(Unable to get list from ftp.openbsd.org, but that is OK)"
		_prompt="HTTP Server? (hostname or 'done')"
	fi

	# Use information from /etc/installurl as defaults for upgrades.
	# Format of installurl: _http_proto://_iu_srv/_iu_dir
	#                       ^--------- _iu_url ---------^
	if [[ $MODE == upgrade ]] &&
		_iu_url=$(stripcom /mnt/etc/installurl); then
		_iu_srv=${_iu_url#*://}
		_iu_srv=${_iu_srv%%/*}
		_iu_dir=${_iu_url##*$_iu_srv*(/)}
		[[ -n $_iu_srv ]] && HTTP_SERVER=$_iu_srv
	fi

	# Get server IP address or hostname and optionally the http protocol.
	while :; do
		ask_until "$_prompt" "$HTTP_SERVER"
		case $resp in
		done)	return
			;;
		"?")	[[ -s $HTTP_LIST ]] || continue
			# Show a numbered list of mirror servers.
			cat -n < $HTTP_LIST | more -c
			;;
		+([0-9]))
			# A number is only used as a line number in $HTTP_LIST.
			[[ -s $HTTP_LIST ]] || continue
			# Extract the URL from the mirror server listfile.
			set -- $(sed -n "${resp}p" $HTTP_LIST)
			if (($# < 1)); then
				echo "There is no line $resp."
				continue
			fi
			HTTP_SERVER=${1%%/*}
			# Repeat loop to get user to confirm server address.
			;;
		?(http?(s)://)+([A-Za-z0-9:.\[\]_-]))
			case $resp in
			https://*)	_tls=force _http_proto=https;;
			http://*)	_tls=no    _http_proto=http;;
			*)		_tls=try   _http_proto=$HTTP_PROTO;;
			esac
			if ! $FTP_TLS && [[ $_tls == force ]]; then
				echo "https not supported on this platform."
				$AI && exit 1 || continue
			fi
			HTTP_SERVER=${resp#*://}
			break
			;;
		*)	echo "'$resp' is not a valid hostname."
			;;
		esac
	done

	# Get directory info from *last* line starting with the server
	# name. This means the last install from a mirror will not keep
	# the specific directory info. But an install from a local
	# server *will* remember the specific directory info.
	# Format: _mirror_srv/_mirror_dir location_info
	#         ^---- _mirror_url ----^
	set -- $(grep -i "^$HTTP_SERVER" $HTTP_LIST 2>/dev/null | sed '$!d')
	_mirror_url=${1%%*(/)}
	_mirror_srv=${_mirror_url%%/*}
	_mirror_dir=${_mirror_url##*$_mirror_srv*(/)}

	# Decide on the default for the "Server directory" question.
	if [[ -n $_mirror_url ]]; then
		# Use directory information from cgi server if HTTP_SERVER was
		# found in HTTP_LIST. That is either an official mirror or the
		# server used in a previous installation or upgrade.
		_d=$_mirror_dir/$HTTP_SETDIR

		# Preserve the information that it is an official mirror if
		# location is present in $2.
		(($# > 1)) && INSTALL_MIRROR=$_mirror_url
	elif [[ -n $_iu_url ]]; then
		# Otherwise, if it exists, use directory information from
		# installurl(5) during upgrade.
		_d=$_iu_dir/$HTTP_SETDIR
	else
		_d=pub/OpenBSD/$HTTP_SETDIR
	fi

	ask_until "Server directory?" "$_d"
	HTTP_DIR=${resp##+(/)}
	_url_base="$_http_proto://$HTTP_SERVER/$HTTP_DIR"

	# Fetch SHA256.sig to create the list of files to select from.
	rm -f $_idx $_sha $_sig $_ftp_stdout
	if ! unpriv -f $_sig \
		ftp -w 15 -vMo $_sig "$_url_base/SHA256.sig" \
			>$_ftp_stdout 2>/dev/null; then
		case $_tls in
		force)	$AI && exit 1 || return
			;;
		try)	ask_yn "Unable to connect using https. Use http instead?" ||
				return
			_http_proto=http
			_url_base="http://$HTTP_SERVER/$HTTP_DIR"
			unpriv -f $_sig ftp -vMo $_sig "$_url_base/SHA256.sig" \
				>$_ftp_stdout 2>/dev/null
			;;
		esac
	fi

	# In case of URL redirection, use the final location to retrieve the
	# rest of the files from. Redirection does not change INSTALL_MIRROR.
	_rurl_base=$(sed -n 's/^Requesting //p' $_ftp_stdout | sed '$!d')
	_rurl_base=${_rurl_base%/SHA256.sig*}

	# Verify SHA256.sig, write SHA256 and extract the list of files.
	if unpriv -f $_sha \
		signify -Vep $PUB_KEY -x $_sig -m $_sha >/dev/null 2>&1; then
		_file_list="$(sed -n 's/^SHA256 (\(.*\)).*$/\1/p' $_sha)"
		_file_list="SHA256.sig $_file_list"
	else
		echo "Unable to get a verified list of distribution sets."
		# Deny this server, if it's a mirror without a valid SHA256.sig.
		if [[ ${_rurl_base%/$HTTP_SETDIR} == "$_http_proto://$INSTALL_MIRROR" ]]; then
			$AI && exit 1 || return
		fi
	fi

	# Fetch index.txt, extract file list but add only entries that are not
	# already in _file_list. This allows for a verified list of distribution
	# sets from SHA256.sig, siteXX sets or the whole set list from index.txt
	# if SHA256.sig was not found (e.g. self compiled sets).
	if unpriv -f $_idx \
		ftp -VMo $_idx "$_rurl_base/index.txt" 2>/dev/null; then
		_flist=$(sed -En 's/^.* ([a-zA-Z][a-zA-Z0-9._-]+)$/\1/p' $_idx)
		for _f in $_flist; do
			! isin "$_f" $_file_list && _file_list="$_file_list $_f"
		done
	fi
	rm -f $_idx $_sha $_sig $_ftp_stdout

	install_files "$_rurl_base" "$_file_list"

	# Remember the sets location which is used later for creating the
	# installurl(5) file and to tell the cgi server.
	if [[ -n $INSTALL_MIRROR ]]; then
		INSTALL_URL=$_http_proto://$INSTALL_MIRROR
	else
		# Remove the architecture and snaphots or version part.
		INSTALL_URL=${_url_base%/$ARCH}
		INSTALL_URL=${INSTALL_URL%@(/$VNAME|/snapshots)}
	fi
}

# Ask for the path to the set files on an already mounted filesystem and start
# the set installation.
install_mounted_fs() {
	local _dir

	while :; do
		ask_until "Pathname to the sets? (or 'done')" "$SETDIR"
		[[ $resp == done ]] && return
		# Accept a valid /mnt2 or /mnt relative path.
		[[ -d /mnt2/$resp ]] && { _dir=/mnt2/$resp; break; }
		[[ -d /mnt/$resp ]] && { _dir=/mnt/$resp; break; }
		# Accept a valid absolute path.
		[[ -d /$resp ]] && { _dir=/$resp; break; }
		echo "The directory '$resp' does not exist."
		$AI && exit 1
	done

	install_files "file://$_dir" "$(ls $_dir/)"
}

# Install sets from CD-ROM drive $1.
install_cdrom() {
	local _drive=$1

	make_dev $_drive && mount_mnt2 $_drive || return

	install_mounted_fs
}

# Install sets from disk.
# Ask for the disk device containing the set files.
install_disk() {
	if ! ask_yn "Is the disk partition already mounted?" yes; then
		ask_which "disk" "contains the $MODE media" \
			'$(bsort $(get_dkdevs))' \
			'$(bsort $(rmel $ROOTDISK $(get_dkdevs)))'
		[[ $resp == done ]] && return 1

		# Ensure the device file exists and mount the fs on /mnt2.
		make_dev $resp && mount_mnt2 $resp || return
	fi

	install_mounted_fs
}

# Ask for the nfs share details, mount it and start the set installation.
install_nfs() {
	local _tcp

	# Get the IP address of the server.
	ask_until "Server IP address or hostname?" "$NFS_ADDR"
	NFS_ADDR=$resp

	# Get the server path to mount.
	ask_until "Filesystem on server to mount?" "$NFS_PATH"
	NFS_PATH=$resp

	# Determine use of TCP.
	ask_yn "Use TCP transport? (requires TCP-capable NFS server)" && _tcp=-T

	# Mount the server.
	mount_nfs $_tcp -o ro -R 5 $NFS_ADDR:$NFS_PATH /mnt2 || return

	install_mounted_fs
}

# Mount filesystem containing the set files on device $1, optionally ask the
# user for the device name.
mount_mnt2() {
	local _dev=$1 _opts _file=/tmp/i/parts.$1 _parts

	disklabel $_dev 2>/dev/null |
		sed -En '/swap|unused/d;/^  [a-p]: /p' >$_file
	_parts=$(sed 's/^  \(.\): .*/\1/' $_file)
	set -- $_parts
	(($# == 0)) && { echo "No filesystems found on $_dev."; return 1; }

	if isin "c" $_parts; then
		# Don't ask questions if 'c' contains a filesystem.
		resp=c
	elif (($# == 1)); then
		# Don't ask questions if there's only one choice.
		resp=$1
	else
		# Display partitions with filesystems and ask which to use.
		cat $_file
		ask_which "$_dev partition" "has the $MODE sets" \
			'$(disklabel '$_dev' 2>/dev/null |
			sed -En '\''/swap|unused/d;/^  ([a-p]): .*/s//\1/p'\'')'
		[[ $resp == done ]] && return 1
	fi

	# Always mount msdos partitions with -s to get lower case names.
	grep -q "^  $resp: .*MSDOS" $_file && _opts="-s"
	mount -o ro,$_opts /dev/$_dev$resp /mnt2
}


# ------------------------------------------------------------------------------
# Functions used in install.sh/upgrade.sh and its associates
# ------------------------------------------------------------------------------

# Ask for terminal type if on console, otherwise ask for/set keyboard layout.
set_term() {
	local _layouts
	export TERM=${TERM:-${MDTERM:-vt220}}

	if [[ -n $CONSOLE ]]; then
		ask "Terminal type?" "$TERM"
		TERM=$resp
	else
		[[ -x /sbin/kbd ]] || return
		_layouts=$(bsort $(kbd -l | egrep -v "^(user|tables|encoding)"))
		while :; do
			ask "Choose your keyboard layout ('?' or 'L' for list)" default
			case $resp in
			[lL\?])		echo "Available layouts: $_layouts"
					;;
			default)	break
					;;
			*)		if kbd -q "$resp"; then
						echo $resp >/tmp/i/kbdtype
						break
					fi
					;;
			esac
		done
	fi
}

# Configure the network.
donetconfig() {
	local _dn _ns _f1 _f2 _f3

	configure_ifs
	v4_defroute
	v6_defroute

	# As dhclient will populate /etc/resolv.conf, a symbolic link to
	# /tmp/i/resolv.conf.shadow, mv any such file to /tmp/i/resolv.conf
	# so it will eventually be copied to /mnt/etc/resolv.conf and will
	# not in the meantime remove the user's ability to choose to use it
	# or not, during the rest of the install.
	if [[ -f /tmp/i/resolv.conf.shadow ]]; then
		mv /tmp/i/resolv.conf.shadow /tmp/i/resolv.conf
		# Get/store nameserver address(es) as a blank separated list
		# and the default fully qualified domain name from *first*
		# domain given on *last* search or domain statement.
		while read -r -- _f1 _f2 _f3; do
			[[ $_f1 == nameserver ]] && _ns="${_ns:+$_ns }$_f2"
			[[ $_f1 == @(domain|search) ]] && _dn=$_f2
		done </tmp/i/resolv.conf
	fi

	# Get & apply fqdn to hostname. Don't ask if there's only one configured
	# interface and if it's managed by dhclient and if the domain name is
	# configured via dhclient too.
	resp="${_dn:-$(get_fqdn)}"
	if ifconfig dhcp >/dev/null 2>&1 && [[ $NIFS == 1 && -n $_dn ]]; then
		# If we have a 'domain-name' option in the lease file use that.
		# It might *NOT* not be the same as the first domain in any
		# 'domain-search' option.
		set -- $(get_ifs dhcp)
		set -- $(lease_value /var/db/dhclient.leases.$1 domain-name)
		[[ -n $1 ]] && resp=$1
		echo "Using DNS domainname $resp"
	else
		ask "DNS domain name? (e.g. 'example.com')" "$resp"
	fi
	hostname "$(hostname -s).$resp"

	# Get & add nameservers to /tmp/i/resolv.conf. Don't ask if there's only
	# one configured interface and if it's managed by dhclient and if the
	# nameserver is configured via dhclient too.
	resp="${_ns:-none}"
	if ifconfig dhcp >/dev/null 2>&1 && [[ $NIFS == 1 && -n $_ns ]]; then
		echo "Using DNS nameservers at $resp"
	else
		ask "DNS nameservers? (IP address list or 'none')" "$resp"
	fi

	# Construct appropriate resolv.conf.
	if [[ $resp != none ]]; then
		echo "lookup file bind" >/tmp/i/resolv.conf
		for _ns in $resp; do
			echo "nameserver $_ns" >>/tmp/i/resolv.conf
		done
		cp /tmp/i/resolv.conf /tmp/i/resolv.conf.shadow
	fi
}

# Ask user about daemon startup on boot, X Window usage and console setup.
# The actual configuration is done later in apply().
questions() {
	local _d _cdef=no

	ask_yn "Start sshd(8) by default?" yes
	START_SSHD=$resp

	APERTURE=
	resp=
	START_XDM=
	if [[ -n $(scan_dmesg '/^wsdisplay[0-9]* /s/ .*//p') ]]; then
		if [[ -n $(scan_dmesg '/^[a-z]*[01]: aperture needed/p') ]]; then
			ask_yn "Do you expect to run the X Window System?" yes &&
				APERTURE=$MDXAPERTURE
		fi
		if [[ -n $MDXDM && $resp != n ]]; then
			ask_yn "Do you want the X Window System to be started by xenodm(1)?"
			START_XDM=$resp
		fi
	fi

	if [[ -n $CDEV ]]; then
		_d=${CPROM:-$CDEV}
		[[ -n $CONSOLE ]] && _cdef=yes
		ask_yn "Change the default console to $_d?" $_cdef
		DEFCONS=$resp
		if [[ $resp == y ]]; then
			ask_which "speed" "should $_d use" \
				"9600 19200 38400 57600 115200" $CSPEED
			case $resp in
			done)	DEFCONS=n;;
			*)	CSPEED=$resp;;
			esac
		fi
	fi
}

# Gather information for setting up the user later in do_install().
user_setup() {
	local _q="Setup a user? (enter a lower-case loginname, or 'no')"

	while :; do
		ask "$_q" no
		case $resp in
		n|no)	return
			;;
		y|yes)	_q="No really, what is the lower-case loginname, or 'no'?"
			continue
			;;
		root|daemon|operator|bin|build|sshd|www|nobody|ftp)
			;;
		[a-z]*([-a-z0-9_]))
			((${#resp} <= 31)) && break
			;;
		esac
		echo "$resp is not a usable loginname."
	done
	ADMIN=$resp
	while :; do
		ask "Full name for user $ADMIN?" "$ADMIN"
		case $resp in
		*[:\&,]*)
			echo "':', '&' or ',' are not allowed."
			;;
		*)
			((${#resp} <= 100)) && break
			echo "Too long."
			;;
		esac
	done
	ADMIN_NAME=$resp

	ask_password "Password for user $ADMIN?"
	ADMIN_PASS=$_password

	ADMIN_KEY=
	$AI && ask "Public ssh key for user $ADMIN" none &&
		[[ $resp != none ]] && ADMIN_KEY=$resp
}

# Ask user whether or not to allow logins to root in case sshd(8) is enabled.
# If no user is setup, show a hint to enable root logins, but warn about risks
# of doing so.
ask_root_sshd() {
	typeset -l _resp

	[[ $START_SSHD == y ]] || return

	if [[ -z $ADMIN ]]; then
		echo "Since no user was setup, root logins via sshd(8) might be useful."
	fi
	echo "WARNING: root is targeted by password guessing attacks, pubkeys are safer."
	while :; do
		ask "Allow root ssh login? (yes, no, prohibit-password)" no
		_resp=$resp
		case $_resp in
		y|yes)	SSHD_ENABLEROOT=yes
			;;
		n|no)	SSHD_ENABLEROOT=no
			;;
		w|p|without-password|prohibit-password)
			SSHD_ENABLEROOT=prohibit-password
			;;
		*)	echo "'$resp' is not a valid choice."
			$AI && exit 1
			continue
			;;
		esac
		break
	done
}

# Set TZ variable based on zonefile $1 and user selection.
set_timezone() {
	local _zonefile=$1 _zonepath _zsed _zoneroot=/usr/share/zoneinfo

	# If the timezone file is not available,
	# return immediately.
	[[ ! -f $_zonefile ]] && return

	# If configured in a previous call, return immediately.
	[[ -n $TZ ]] && return

	if [[ -h /mnt/etc/localtime ]]; then
		TZ=$(ls -l /mnt/etc/localtime 2>/dev/null)
		TZ=${TZ#*${_zoneroot#/mnt}/}
	fi

	wait_cgiinfo
	isin "$CGI_TZ" $(<$_zonefile) && TZ=$CGI_TZ

	# If neither the base or HTTP_LIST gave a hint, and this is the
	# early question, give up, and ask after the sets are installed.
	[[ $_zonefile == /var/tzlist && -z $TZ ]] && return

	while :; do
		ask "What timezone are you in? ('?' for list)" "$TZ"
		_zonepath=${resp%%*(/)}
		case $_zonepath in
		"")	continue
			;;
		"?")	grep -v /. $_zonefile | show_cols
			continue
			;;
		esac

		while isin "$_zonepath/" $(<$_zonefile); do
			ask "What sub-timezone of '$_zonepath' are you in? ('?' for list)"
			_zsed=$(echo $_zonepath/ | sed 's,/,\\/,g')
			resp=${resp%%*(/)}
			case $resp in
			"")	;;
			"?")	sed -n "/^$_zsed/{s/$_zsed//;/\/./!p;}" $_zonefile | show_cols;;
			*)	_zonepath=$_zonepath/$resp;;
			esac
		done

		if isin "$_zonepath" $(<$_zonefile); then
			TZ=${_zonepath#$_zoneroot}
			return
		fi

		echo -n "'${_zonepath}'"
		echo " is not a valid timezone on this system."
	done
}

# Determine if the supplied disk is a potential root disk, by:
# - Check the disklabel if there is an 'a' partition of type 4.2BSD
# - Mount the partition (read-only) and look for typical root filesystem layout
is_rootdisk() {
	local _d=$1 _rc=1

	(
		make_dev $_d
		if disklabel $_d | grep -q '^  a: .*4\.2BSD ' &&
			mount -t ffs -r /dev/${_d}a /mnt; then
			if $UU; then
				ls -d /mnt/{auto_upgrade.conf,bin,dev,etc,home,mnt,root,sbin,tmp,usr,var}
			else
				ls -d /mnt/{bin,dev,etc,home,mnt,root,sbin,tmp,usr,var}
			fi
			_rc=$?
			umount -f /mnt
		fi
		rm -f /dev/{r,}$_d?
		return $_rc
	) >/dev/null 2>&1
}

# Get global root information. ie. ROOTDISK, ROOTDEV and SWAPDEV.
get_rootinfo() {
	local _default=$(get_dkdevs_root) _dkdev
	local _q="Which disk is the root disk? ('?' for details)"

	while :; do
		echo "Available disks are: $(get_dkdevs_root | sed 's/^$/none/')."
		_ask "$_q" $_default || continue
		case $resp in
		"?")	diskinfo $(get_dkdevs);;
		'')	;;
		*)	# Translate $resp to disk dev name in case it is a DUID.
			# get_dkdev_name bounces back the disk dev name if not.
			_dkdev=$(get_dkdev_name "$resp")
			if isin "$_dkdev" $(get_dkdevs); then
				[[ $MODE == install ]] && break
				is_rootdisk "$_dkdev" && break
				echo "$resp is not a valid root disk."
				_default="$(rmel "$_dkdev" $_default) $_dkdev"
			else
				echo "no such disk"
			fi
			;;
		esac
		$AI && exit 1
	done
	log_answers "$_q" "$resp"

	make_dev $_dkdev || exit

	ROOTDISK=$_dkdev
	ROOTDEV=${ROOTDISK}a
	SWAPDEV=${ROOTDISK}b
}

# Parse and "unpack" a hostname.if(5) line given as positional parameters.
# Fill the _cmds array with the resulting interface configuration commands.
parse_hn_line() {
	local _af=0 _name=1 _mask=2 _bc=3 _prefix=2 _c _cmd _prev _daddr _dhcp _i
	local _has_dhclient=false _has_inet6=false
	set -A _c -- "$@"
	set -o noglob

	ifconfig $_if inet6 >/dev/null 2>&1 && _has_inet6=true
	[[ -x /sbin/dhclient ]] && _has_dhclient=true

	# XXX Reverse when dhcpleased is made the default.
	if  { [[ ${_c[_af]} == inet ]] && [[ ${_c[_name]} == autoconf ]]; } ||
	    { [[ ${_c[_af]} == autoconf ]]; }; then
		# emulate "[inet] autoconf" with "dhcp"
		[[ ${_c[_af]} == inet ]] && shift 2 || shift 1
		set -A _c -- dhcp "$@"
	fi

	case ${_c[_af]} in
	''|*([[:blank:]])'#'*)
		return
		;;
	inet)	((${#_c[*]} > 1)) || return
		[[ ${_c[_name]} == alias ]] && _mask=3 _bc=4
		[[ -n ${_c[_mask]} ]] && _c[_mask]="netmask ${_c[_mask]}"
		if [[ -n ${_c[_bc]} ]]; then
			_c[_bc]="broadcast ${_c[_bc]}"
			[[ ${_c[_bc]} == *NONE ]] && _c[_bc]=
		fi
		_cmds[${#_cmds[*]}]="ifconfig $_if ${_c[@]}"
		;;
	inet6)	! $_has_inet6 && return
		((${#_c[*]} > 1)) || return
		if [[ ${_c[_name]} == autoconf ]]; then
			_cmds[${#_cmds[*]}]="ifconfig $_if ${_c[@]}"
			V6_AUTOCONF=true
			return
		fi
		[[ ${_c[_name]} == alias ]] && _prefix=3
		[[ -n ${_c[_prefix]} ]] && _c[_prefix]="prefixlen ${_c[_prefix]}"
		_cmds[${#_cmds[*]}]="ifconfig $_if ${_c[@]}"
		;;
	dest)	((${#_c[*]} == 2)) && _daddr=${_c[1]} || return
		! $_has_inet6 && [[ $_daddr == @(*:*) ]] && return
		_prev=$((${#_cmds[*]} - 1))
		((_prev >= 0)) || return
		set -A _c -- ${_cmds[_prev]}
		_name=3
		[[ ${_c[_name]} == alias ]] && _name=4
		_c[_name]="${_c[_name]} $_daddr"
		_cmds[$_prev]="${_c[@]}"
		;;
	dhcp)	! $_has_dhclient && return
		unset _c[0]
		_i=1
		while [[ ${_c[$_i]} == @(-c|-d|-i|-n|-r|-v) ]]; do
			if [[ ${_c[$_i]} == @(-c|-i) ]]; then
				_dhcp[${#_dhcp[*]}]=${_c[$_i]}
				unset _c[$_i]
				(( _i++ ))
			fi
			_dhcp[${#_dhcp[*]}]=${_c[$_i]}
			unset _c[$_i]
			(( _i++ ))
		done
		((${#_c[*]} > 0)) && _cmds[${#_cmds[*]}]="ifconfig $_if ${_c[@]}"
		_cmds[${#_cmds[*]}]="dhclient ${_dhcp[@]} $_if"
		V4_DHCPCONF=true
		;;
	'!'*|bridge)
		# Skip shell commands and bridge in the installer.
		return
		;;
	*)	_cmds[${#_cmds[*]}]="ifconfig $_if ${_c[@]}"
		;;
	esac
	unset _c
	set +o noglob
}

# Start interface using the on-disk hostname.if file passed as argument $1.
# Much of this is gratuitously stolen from /etc/netstart.
ifstart() {
	local _if=$1 _hn=/mnt/etc/hostname.$1 _cmds _i=0 _line
	set -A _cmds

	# Create interface if it does not yet exist.
	{ ifconfig $_if || ifconfig $_if create; } >/dev/null 2>&1 || return

	((NIFS++))

	# Parse the hostname.if(5) file and fill _cmds array with interface
	# configuration commands.
	set -o noglob
	while IFS= read -- _line; do
		parse_hn_line $_line
	done <$_hn

	# Apply the interface configuration commands stored in _cmds array.
	while ((_i < ${#_cmds[*]})); do
		eval "${_cmds[_i]}"
		((_i++))
	done
	unset _cmds
	set +o noglob
}

# Configure the network during upgrade based on the on-disk configuration.
enable_network() {
	local _f _gw _v4set=false _v6set=false _hn _if _trunks _svlans _vlans

	# Use installed network configuration files during upgrade.
	for _f in dhclient.conf resolv.conf resolv.conf.tail; do
		if [[ -f /mnt/etc/$_f ]]; then
			cp /mnt/etc/$_f /etc/$_f
		fi
	done

	# Create a minimal hosts file.
	echo "127.0.0.1\tlocalhost" >/tmp/i/hosts
	echo "::1\t\tlocalhost" >>/tmp/i/hosts

	_f=/mnt/etc/soii.key
	[[ -f $_f ]] && sysctl "net.inet6.ip6.soiikey=$(<$_f)"

	# Set the address for the loopback interface. Bringing the
	# interface up, automatically invokes the IPv6 address ::1.
	ifconfig lo0 inet 127.0.0.1/8

	# Configure all of the non-loopback interfaces which we know about.
	# Refer to hostname.if(5)
	for _hn in /mnt/etc/hostname.*; do
		# Strip off prefix to get interface name.
		_if=${_hn#/mnt/etc/hostname.}
		if isin "${_if%%+([0-9])}" $(ifconfig -C); then
			# Dynamic interfaces must be done later.
			case ${_if%%+([0-9])} in
			trunk)	_trunks="$_trunks $_if";;
			svlan)	_svlans="$_svlans $_if";;
			vlan)	_vlans="$_vlans $_if";;
			esac
		else
			# 'Real' interfaces (if available) are done now.
			ifconfig $_if >/dev/null 2>&1 && ifstart $_if
		fi
	done
	# Configure any dynamic interfaces now that 'real' ones are up.
	# ORDER IS IMPORTANT! (see /etc/netstart).
	for _if in $_trunks $_svlans $_vlans; do
		ifstart $_if
	done

	# /mnt/etc/mygate, if it exists, contains the address(es) of my
	# default gateway(s). Use for ipv4 if no interfaces configured via
	# dhcp. Use for ipv6 if no interfaces configured via autoconf.
	stripcom /mnt/etc/mygate |
	while read _gw; do
		case $_gw in
		'!'*)
			# Skip shell commands in the installer.
			continue
			;;
		!(*:*))
			($_v4set || $V4_DHCPCONF) && continue
			route -qn add -host default $_gw
			_v4set=true
			;;
		*)
			($_v6set || $V6_AUTOCONF) && continue
			route -qn add -host -inet6 default $_gw
			_v6set=true
			;;
		esac
	done

	route -qn add -net 127 127.0.0.1 -reject >/dev/null
}

# Fetch the list of mirror servers and installer choices from previous runs if
# available from ftplist.cgi. Start the ftp process in the background, but kill
# it if it takes longer than 12 seconds.
start_cgiinfo() {
	# If no networks are configured, we do not need the httplist file.
	((NIFS < 1)) && return

	# Ensure proper name resolution in case there's no dns yet.
	add_hostent 129.128.5.191 ftp.openbsd.org

	# Make sure the ftp subshell gets its own process group.
	set -m
	(
		unpriv2 ftp -w 15 -Vao - \
			"$HTTP_PROTO://ftp.openbsd.org/cgi-bin/ftplist.cgi?dbversion=1" \
			2>/dev/null >$CGI_INFO

		# Remember finish time for adjusting the received timestamp.
		echo -n $SECONDS >$HTTP_SEC
		feed_random
	) & CGIPID=$!
	set +m

	# If the ftp process takes more than 12 seconds, kill it.
	# XXX We are relying on the pid space not randomly biting us.
	# XXX ftp could terminate early, and the pid could be reused.
	(sleep 12; kill -INT -$CGIPID >/dev/null 2>&1) &
}

# Create a skeletal but useful /etc/fstab from /tmp/i/fstab by stripping all
# comment lines and dropping all filesystems which
#
# 1) can't be mounted (no mount_* command is found),
# 2) have 'xx' in the option field (usually /altroot),
# 3) have 'noauto' in the option field,
# 4) are nfs (since name resolution may not be present),
# 5) are on a vnd device.
#
# In addition,
#
# 1) delete 'softdep' options (no soft updates in ramdisk kernels),
# 2) mount non-ffs filesystems read only,
# 3) prepend '/mnt' to all mount points,
# 4) delete any trailing '/' from the mount point (e.g. root),
#
# If no /etc/fstab is created, do not proceed with install/upgrade.
munge_fstab() {
	local _dev _mp _fstype _opt _rest

	while read _dev _mp _fstype _opt _rest; do
		# Drop irrelevant lines and filesystems.
		[[ $_dev == @(/dev/vnd*|\#*) ||
			$_fstype == nfs ||
			! -f /sbin/mount_$_fstype ||
			$_opt == *noauto* ||
			$_opt == *xx* ]] && continue

		# Remove any softdep options, as soft updates are not
		# available in the ramdisk kernels.
		_opt=$(echo $_opt | sed 's/softdep//')

		# Change read-only ffs to read-write since we'll potentially
		# write to these filesystems.
		# Mount non-ffs filesystems read only.
		if [[ $_fstype == ffs ]]; then
			_opt=$(echo $_opt | sed 's/[[:<:]]ro[[:>:]]/rw/')
		else
			_opt=$(echo $_opt | sed 's/[[:<:]]rw[[:>:]]/ro/')
		fi

		# Write fs entry in fstab.
		# 1) prepend '/mnt' to the mount point.
		# 2) remove a trailing '/' from the mount point (e.g. root).
		echo $_dev /mnt${_mp%/} $_fstype $_opt $_rest

	done </tmp/i/fstab >/etc/fstab

	# If no /etc/fstab was created, we have nowhere to $MODE to.
	if [[ ! -s /etc/fstab ]]; then
		echo "Unable to create valid /etc/fstab."
		exit
	fi
}

# Preen all filesystems in /etc/fstab that have a /sbin/fsck_XXX and a
# fs_passno > 0, showing individual results, but skipping $ROOTDEV. This was
# already fsck'ed successfully.
#
# Exit if any fsck's fail (but do them all before exiting!).
check_fs() {
	local _dev _dn _mp _fstype _rest _fail _f _passno

	ask_yn "Force checking of clean non-root filesystems?" && _f=f

	while read _dev _mp _fstype _rest _rest _passno _rest; do
		_dn=$(get_dkdev_name "$_dev")
		[[ $ROOTDEV == @(${_dev#/dev/}|$_dn${_dev##*.}) ]] && continue
		[[ -f /sbin/fsck_$_fstype ]] || continue
		# Make sure device exists before fsck'ing it.
		make_dev "$_dn" || continue
		((_passno > 0)) || continue
		echo -n "fsck -${_f}p $_dev..."
		if ! fsck -${_f}p $_dev >/dev/null 2>&1; then
			echo " FAILED. You must fsck $_dev manually."
			_fail=y
		else
			echo " OK."
		fi
	done </etc/fstab

	[[ -n $_fail ]] && exit
}

# Must mount filesystems manually, one at a time, so we can make sure the mount
# points exist.
mount_fs() {
	local _async=$1 _dev _mp _fstype _opt _rest _msg _fail

	while read _dev _mp _fstype _opt _rest; do
		# If not the root filesystem, make sure the mount
		# point is present.
		[[ $_mp == /mnt ]] || mkdir -p $_mp

		# Mount the filesystem. Remember any failure.
		_msg=$(mount -v -t $_fstype $_async -o $_opt $_dev $_mp) ||
			_fail="$_fail\n$_mp ($_dev)"
		echo $_msg | sed 's/, ctime=[^,)]*//'
	done </etc/fstab

	if [[ -n $_fail ]]; then
		# One or more mounts failed. Continue or abort?
		echo "\nWARNING! The following filesystems were not properly mounted:$_fail"
		ask_yn "Continue anyway?" || exit
	fi
}

# Feed the random pool some entropy before we read from it.
feed_random() {
	(dmesg; cat $CGI_INFO /*.conf; sysctl; route -n show; df;
		ifconfig -A; hostname) >/dev/random 2>&1
	if [[ -e /mnt/var/db/host.random ]]; then
		dd if=/mnt/var/db/host.random of=/dev/random bs=65536 count=1 \
			status=none
	fi
}

# Ask the user for locations of sets, and then install whatever sets the user
# selects from that location. Repeat as many times as the user needs to get all
# desired sets.
install_sets() {
	local _cddevs=$(get_cddevs) _d _im _locs="disk http" _src

	echo

	# Set default location to method recorded last time.
	_d=$CGI_METHOD

	# Set default location to HTTP in case we netbooted.
	ifconfig netboot >/dev/null 2>&1 && : ${_d:=http}

	# Set default location to HTTP if installurl(5) exists.
	[[ -s /mnt/etc/installurl ]] && _d=http

	# Set default location to the first cdrom device if any are found.
	[[ -n $_cddevs ]] && : ${_d:=cd0}

	# Add NFS to set locations if the boot kernel supports it.
	[[ -x /sbin/mount_nfs ]] && _locs="$_locs nfs"

	# In case none of the above applied, set HTTP as default location.
	: ${_d:=http}

	# If the default location set so far is not one of the cdrom devices or
	# is not in the list of valid locations, set a sane default.
	if ! isin "$_d" $_cddevs $_locs; then
		for _src in http $_cddevs nfs disk; do
			isin "$_src" $_cddevs $_locs && _d=$_src && break
		done
	fi

	echo "Let's $MODE the sets!"
	while :; do
		# Get list of cdroms again in case one just got plugged in.
		_cddevs=$(get_cddevs)
		umount -f /mnt2 >/dev/null 2>&1

		ask "Location of sets? (${_cddevs:+$_cddevs }$_locs or 'done')" "$_d"
		case $resp in
		done)	sane_install && return
			;;
		[cC]*)	if [[ -n $_cddevs ]]; then
				set -- $_cddevs
				[[ $resp == [cC]?([dD]) ]] && resp=$1
				_im=$resp
				install_cdrom $resp && INSTALL_METHOD=$_im
			fi
			;;
		[dD]*)	install_disk && INSTALL_METHOD=disk
			;;
		[hH]*)	isin http $_locs && install_http && INSTALL_METHOD=http
			;;
		[nN]*)	isin nfs $_locs && install_nfs && INSTALL_METHOD=nfs
			;;
		*)	$AI && err_exit "'$resp' is not a valid choice."
			;;
		esac

		# Preserve the selected install source selection.
		[[ -n $INSTALL_METHOD ]] && _d=$INSTALL_METHOD

		# Set default to 'done' to leave the while-loop.
		sane_install quiet || $AI && _d=done
	done
}

# Apply configuration settings based on the previously gathered information.
apply() {
	if [[ $START_SSHD == n ]]; then
		echo "sshd_flags=NO" >>/mnt/etc/rc.conf.local
	elif [[ -n $SSHD_ENABLEROOT ]]; then
		# Only change sshd_config if the user choice is not the default.
		if ! grep -q "^#PermitRootLogin $SSHD_ENABLEROOT\$" \
				/mnt/etc/ssh/sshd_config; then
			sed -i "s/^#\(PermitRootLogin\) .*/\1 $SSHD_ENABLEROOT/" \
				/mnt/etc/ssh/sshd_config
		fi
	fi

	[[ -n $APERTURE ]] &&
		echo "machdep.allowaperture=$APERTURE # See xf86(4)" \
			>>/mnt/etc/sysctl.conf

	[[ $START_XDM == y && -x /mnt/usr/X11R6/bin/xenodm ]] &&
		echo "xenodm_flags=" >>/mnt/etc/rc.conf.local

	if [[ $DEFCONS == y ]]; then
		cp /mnt/etc/ttys /tmp/i/ttys
		sed	-e "/^$CTTY/s/std.9600/std.${CSPEED}/" \
			-e "/^$CTTY/s/std.115200/std.${CSPEED}/" \
			-e "/^$CTTY/s/unknown/vt220	/" \
			-e "/$CTTY/s/off.*/on secure/" /tmp/i/ttys >/mnt/etc/ttys
		[[ -n $CPROM ]] &&
			echo "stty $CPROM $CSPEED\nset tty $CPROM" \
				>>/mnt/etc/boot.conf
	fi

	ln -sf /usr/share/zoneinfo/$TZ /mnt/etc/localtime
}

# Return string suitable for the encrypted password field in master.passwd.
#
# 1) Without argument, return a single '*'.
# 2) Return argument unchanged if it looks like a encrypted password string
#    or if it consists of just 13 asterisks.
# 3) Otherwise return encrypted password string.
#
encr_pwd() {
	local _p=$1

	if [[ -z $_p ]]; then
		echo '*'
	elif [[ $_p == \$2?\$[0-9][0-9]\$* && ${#_p} > 40 ||
		$_p == '*************' ]]; then
		echo "$_p"
	else
		encrypt -b a -- "$_p"
	fi
}

# Store entropy for the next boot.
store_random() {
	dd if=/dev/random of=/mnt/var/db/host.random bs=65536 count=1 \
		status=none
	dd if=/dev/random of=/mnt/etc/random.seed bs=512 count=1 status=none
	chmod 600 /mnt/var/db/host.random /mnt/etc/random.seed
}

# Final steps common for installs and upgrades.
finish_up() {
	local _dev _mp _fstype _rest _d
	local _kernel_dir=/mnt/usr/share/relink/kernel
	local _kernel=${MDKERNEL:-GENERIC} _syspatch_archs="amd64 arm64 i386"

	# Mount all known swap partitions.  This gives systems with little
	# memory a better chance at running 'MAKEDEV all'.
	if [[ -x /mnt/sbin/swapctl ]]; then
		/mnt/sbin/swapctl -a /dev/$SWAPDEV >/dev/null 2>&1
		# Can't do chmod && swapctl -A because devices are not yet
		# created on install'ed systems. On upgrade'ed system there
		# is a small chance the device does not exist on the ramdisk
		# and will thus not get mounted.
		while read _dev _mp _fstype _rest; do
			[[ $_fstype == swap ]] &&
				/mnt/sbin/swapctl -a $_dev >/dev/null 2>&1
		done </mnt/etc/fstab
	fi

	# Create /etc/installurl if it does not yet exist.
	if [[ ! -f /mnt/etc/installurl ]]; then
		echo "${INSTALL_URL:-https://cdn.openbsd.org/pub/OpenBSD}" \
			>/mnt/etc/installurl
	fi

	echo -n "Making all device nodes..."
	(cd /mnt/dev; sh MAKEDEV all
		# Make sure any devices we found during probe are created in the
		# installed system.
		for _dev in $(get_dkdevs) $(get_cddevs); do
			sh MAKEDEV $_dev
		done
	)
	echo " done."

	# We may run some programs in chroot, and some of them might be
	# dynamic.  That is highly discouraged, but let us play it safe.
	rm -f /mnt/var/run/ld.so.hints

	# Conditionally create /usr/{src,obj,xobj} directories and set
	# proper ownership and permissions during install.
	if [[ $MODE == install ]]; then
		mkdir -p /mnt/usr/{src,{,x}obj} && (
			cd /mnt/usr
			chmod 770 {,x}obj
			chown build:wobj {,x}obj
			chmod 775 src
			chown root:wsrc src
		)
	fi

	# In case this is a softraid device, make sure all underlying
	# device nodes exist before installing boot-blocks on disk.
	make_dev $(bioctl $ROOTDISK 2>/dev/null | sed -n 's/.*<\(.*\)>$/\1/p')
	md_installboot $ROOTDISK

	chmod og-rwx /mnt/bsd{,.mp,.rd} 2>/dev/null
	if [[ -f /mnt/bsd.mp ]] && ((NCPU > 1)); then
		_kernel=$_kernel.MP
		echo "Multiprocessor machine; using bsd.mp instead of bsd."
		mv /mnt/bsd /mnt/bsd.sp 2>/dev/null
		mv /mnt/bsd.mp /mnt/bsd
	fi

	# Write kernel.SHA256 matching the just installed kernel and fix path to
	# ensure it references the kernel as /bsd.
	sha256 /mnt/bsd | (umask 077; sed 's,/mnt,,' >/mnt/var/db/kernel.SHA256)

	if [[ -f $_kernel_dir.tgz ]]; then
		echo -n "Relinking to create unique kernel..."
		(
		set -e
		rm -rf $_kernel_dir
		mkdir -m 700 -p $_kernel_dir
		tar -C $_kernel_dir -xzf $_kernel_dir.tgz $_kernel
		rm -f $_kernel_dir.tgz
		chroot /mnt /bin/ksh -e -c "cd ${_kernel_dir#/mnt}/$_kernel; \
			make newbsd; make newinstall"
		) >/dev/null 2>&1 && echo " done." || echo " failed."
	fi

	# Ensure that sysmerge in batch mode is run on reboot.
	[[ $MODE == upgrade ]] &&
		echo "/usr/sbin/sysmerge -b" >>/mnt/etc/rc.sysmerge

	# If a proxy was needed to fetch the sets, use it for fw_update and syspatch
	[[ -n $http_proxy ]] &&
		quote export "http_proxy=$http_proxy" >>/mnt/etc/rc.firsttime

	# Ensure that fw_update is run on reboot.
	echo "/usr/sbin/fw_update -v" >>/mnt/etc/rc.firsttime

	# Run syspatch -c on reboot if the arch is supported and if it is a
	# release system (not -stable or -current). List uninstalled syspatches
	# on the console and in the rc.firsttime output mail.
	isin "$ARCH" $_syspatch_archs && cat <<__EOT >>/mnt/etc/rc.firsttime
set -A _KERNV -- \$(sysctl -n kern.version |
	sed 's/^OpenBSD \([1-9][0-9]*\.[0-9]\)\([^ ]*\).*/\1 \2/;q')
if ((\${#_KERNV[*]} == 1)) && [[ -s /etc/installurl ]] &&
	_CKPATCH=\$(mktemp /tmp/_ckpatch.XXXXXXXXXX); then
	echo "Checking for available binary patches..."
	syspatch -c > \$_CKPATCH
	if [[ -s \$_CKPATCH ]]; then
		echo "Run syspatch(8) to install:"
		column -xc 80 \$_CKPATCH
	fi
	rm -f \$_CKPATCH
fi
__EOT

	# Email installer questions and their answers to root on next boot.
	prep_root_mail /tmp/i/$MODE.resp "$(hostname) $MODE response file"

	if [[ -x /mnt/$MODE.site ]]; then
		if ! chroot /mnt /$MODE.site; then
			store_random
			err_exit "$MODE.site failed"
		fi
	fi

	# Store entropy for the next boot.
	store_random

	# Pat on the back.
	cat <<__EOT

CONGRATULATIONS! Your OpenBSD $MODE has been successfully completed!

__EOT
	[[ $MODE == install ]] && cat <<__EOT
When you login to your new system the first time, please read your mail
using the 'mail' command.

__EOT

	md_congrats
	$AI && >/tmp/ai/ai.done
}

do_autoinstall() {
	rm -f /tmp/ai/ai.done

	echo "Performing non-interactive $AI_MODE..."
	/$AI_MODE -af /tmp/ai/ai.$AI_MODE.conf 2>&1 </dev/null |
		tee /dev/stderr | sed "s/^.*$(echo '\r')//" >/tmp/ai/ai.log

	$UU || [[ -f /tmp/ai/ai.done ]] ||
		err_exit "failed; check /tmp/ai/ai.log"

	# Email autoinstall protocol to root on next boot.
	prep_root_mail /tmp/ai/ai.log "$(hostname) $AI_MODE log"

	exec reboot
}

do_install() {
	local _rootkey _rootpass

	# Ask for and set the system hostname and add the hostname specific
	# siteXX set.
	while :; do
		ask_until "System hostname? (short form, e.g. 'foo')" \
			"$(hostname -s)"
		[[ $resp != *+([[:cntrl:]]|[[:space:]])* ]] && break
		echo "Invalid hostname."
		$AI && exit 1
	done
	[[ ${resp%%.*} != $(hostname -s) ]] && hostname "$resp"
	ALLSETS="$ALLSETS site$VERSION-$(hostname -s).tgz"
	export PS1='\h# '

	echo

	# Configure the network.
	donetconfig

	# Fetch list of mirror servers and installer choices from previous runs.
	start_cgiinfo

	echo

	while :; do
		ask_password "Password for root account?"
		_rootpass="$_password"
		[[ -n "$_password" ]] && break
		echo "The root password must be set."
	done

	# Ask for the root user public ssh key during autoinstall.
	_rootkey=
	if $AI; then
		ask "Public ssh key for root account?" none
		[[ $resp != none ]] && _rootkey=$resp
	fi

	# Ask user about daemon startup on boot, X Window usage and console
	# setup.
	questions

	# Gather information for setting up the initial user account.
	user_setup
	ask_root_sshd

	# Set TZ variable based on zonefile and user selection.
	set_timezone /var/tzlist

	echo

	# Get information about ROOTDISK, etc.
	get_rootinfo

	DISKS_DONE=
	FSENT=

	# Remove traces of previous install attempt.
	rm -f /tmp/i/fstab*

	# Configure the disk(s).
	while :; do
		# Always do ROOTDISK first, and repeat until it is configured.
		if ! isin "$ROOTDISK" $DISKS_DONE; then
			resp=$ROOTDISK
			rm -f /tmp/i/fstab
		else
			# Force the user to think and type in a disk name by
			# making 'done' the default choice.
			ask_which "disk" "do you wish to initialize" \
				'$(get_dkdevs_uninitialized)' done
			[[ $resp == done ]] && break
		fi
		_disk=$resp
		configure_disk $_disk || continue
		DISKS_DONE=$(addel $_disk $DISKS_DONE)
	done

	# Write fstab entries to fstab in mount point alphabetic order
	# to enforce a rational mount order.
	for _mp in $(bsort $FSENT); do
		_pp=${_mp##*!}
		_mp=${_mp%!*}
		echo -n "$_pp $_mp ffs rw"

		# Only '/' is neither nodev nor nosuid. i.e. it can obviously
		# *always* contain devices or setuid programs.
		[[ $_mp == / ]] && { echo " 1 1"; continue; }

		# Every other mounted filesystem is nodev. If the user chooses
		# to mount /dev as a separate filesystem, then on the user's
		# head be it.
		echo -n ",nodev"

		# The only directories that the install puts suid binaries into
		# (as of 3.2) are:
		#
		# /sbin
		# /usr/bin
		# /usr/sbin
		# /usr/libexec
		# /usr/libexec/auth
		# /usr/X11R6/bin
		#
		# and ports and users can do who knows what to /usr/local and
		# sub directories thereof.
		#
		# So try to ensure that only filesystems that are mounted at
		# or above these directories can contain suid programs. In the
		# case of /usr/libexec, give blanket permission for
		# subdirectories.
		case $_mp in
		/sbin|/usr)			;;
		/usr/bin|/usr/sbin)		;;
		/usr/libexec|/usr/libexec/*)	;;
		/usr/local|/usr/local/*)	;;
		/usr/X11R6|/usr/X11R6/bin)	;;
		*)	echo -n ",nosuid"	;;
		esac
		echo " 1 2"
	done >>/tmp/i/fstab

	# Create a skeletal /etc/fstab which is usable for the installation
	# process.
	munge_fstab

	# Use async options for faster mounts of the filesystems.
	mount_fs "-o async"

	# Feed the random pool some entropy before we read from it.
	feed_random

	# Ask the user for locations, and install whatever sets the user
	# selected.
	install_sets

	# Set 'wxallowed' mount option for the filesystem /usr/local resides on.
	_mp=$(df /mnt/usr/local | sed '$!d')
	_mp=${_mp##*/mnt}
	sed -i "s#\(${_mp:-/} ffs rw\)#\1,wxallowed#" /tmp/i/fstab

	# If we did not succeed at setting TZ yet, we try again
	# using the timezone names extracted from the base set.
	if [[ -z $TZ ]]; then
		(cd /mnt/usr/share/zoneinfo
			ls -1dF $(tar cvf /dev/null [A-Za-y]*) >/mnt/tmp/tzlist )
		echo
		set_timezone /mnt/tmp/tzlist
		rm -f /mnt/tmp/tzlist
	fi

	# If we got a timestamp from the cgi server, and that time diffs by more
	# than 120 seconds, ask if the user wants to adjust the time.
	if _time=$(http_time) && _now=$(date +%s) &&
		(( _now - _time > 120 || _time - _now > 120 )); then
		_tz=/mnt/usr/share/zoneinfo/$TZ
		if ask_yn "Time appears wrong.  Set to '$(TZ=$_tz date -r "$(http_time)")'?" yes; then
			# We do not need to specify TZ below since both date
			# invocations use the same one.
			date $(date -r "$(http_time)" "+%Y%m%d%H%M.%S") >/dev/null
			# N.B. This will screw up SECONDS.
		fi
	fi

	# If we managed to talk to the cgi server before, tell it what
	# location we used... so it can perform magic next time.
	if [[ -s $HTTP_LIST ]]; then
		_i=${INSTALL_URL:+install=$INSTALL_URL&}
		_i=$_i${TZ:+TZ=$TZ&}
		_i=$_i${INSTALL_METHOD:+method=$INSTALL_METHOD}
		_i=${_i%&}
		[[ -n $_i ]] && unpriv2 ftp -w 15 -Vao - \
			"$HTTP_PROTO://ftp.openbsd.org/cgi-bin/ftpinstall.cgi?dbversion=1&$_i" \
			 >/dev/null 2>&1 &
	fi

	# Ensure an enabled console has the correct speed in /etc/ttys.
	sed "/^console.*on.*secure.*$/s/std\.[0-9]*/std.$(stty speed </dev/console)/" \
		/mnt/etc/ttys >/tmp/i/ttys
	mv /tmp/i/ttys /mnt/etc/ttys

	echo -n "Saving configuration files..."

	# Save any leases obtained during install.
	(cd /var/db; for _f in dhclient.leases.*; do
		[[ -f $_f ]] && mv $_f /mnt/var/db/.
	done)

	# Move configuration files from /tmp/i/ to /mnt/etc.
	hostname >/tmp/i/myname

	# Append entries to installed hosts file, changing '1.2.3.4 hostname'
	# to '1.2.3.4 hostname.$FQDN hostname'. Leave untouched lines containing
	# domain information or aliases. These are lines the user added/changed
	# manually.

	# Add common entries.
	echo "127.0.0.1\tlocalhost" >/mnt/etc/hosts
	echo "::1\t\tlocalhost" >>/mnt/etc/hosts

	# Note we may have no hosts file if no interfaces were configured.
	if [[ -f /tmp/i/hosts ]]; then
		# Remove the entry for ftp.openbsd.org
		sed -i '/^129\.128\.5\.191 /d' /tmp/i/hosts
		_dn=$(get_fqdn)
		while read _addr _hn _aliases; do
			if [[ -n $_aliases || $_hn != ${_hn%%.*} || -z $_dn ]]; then
				echo "$_addr\t$_hn $_aliases"
			else
				echo "$_addr\t$_hn.$_dn $_hn"
			fi
		done </tmp/i/hosts >>/mnt/etc/hosts
		rm /tmp/i/hosts
	fi

	# Possible files to copy from /tmp/i/: fstab hostname.* kbdtype mygate
	#     myname ttys boot.conf resolv.conf sysctl.conf resolv.conf.tail
	# Save only non-empty (-s) regular (-f) files.
	(cd /tmp/i; for _f in fstab hostname* kbdtype my* ttys *.conf *.tail; do
		[[ -f $_f && -s $_f ]] && mv $_f /mnt/etc/.
	done)

	echo " done."

	# Apply configuration settings based on information from questions().
	apply

	# Create user account based on information from user_setup().
	if [[ -n $ADMIN ]]; then
		_encr=$(encr_pwd "$ADMIN_PASS")
		_home=/home/$ADMIN
		uline="${ADMIN}:${_encr}:1000:1000:staff:0:0:${ADMIN_NAME}:$_home:/bin/ksh"
		echo "$uline" >>/mnt/etc/master.passwd
		echo "${ADMIN}:*:1000:" >>/mnt/etc/group
		echo $ADMIN >/mnt/root/.forward

		_home=/mnt$_home
		mkdir -p $_home
		(cd /mnt/etc/skel; pax -rw -k -pe . $_home)
		(umask 077 && sed "s,^To: root\$,To: ${ADMIN_NAME} <${ADMIN}>," \
			/mnt/var/mail/root >/mnt/var/mail/$ADMIN )
		chown -R 1000:1000 $_home /mnt/var/mail/$ADMIN
		sed -i -e "s@^wheel:.:0:root\$@wheel:\*:0:root,${ADMIN}@" \
			/mnt/etc/group 2>/dev/null

		# During autoinstall, add public ssh key to authorized_keys.
		[[ -n "$ADMIN_KEY" ]] &&
			print -r -- "$ADMIN_KEY" >>$_home/.ssh/authorized_keys
	fi

	# Store root password and rebuild password database.
	if [[ -n "$_rootpass" ]]; then
		_encr=$(encr_pwd "$_rootpass")
		sed -i -e "s@^root::@root:${_encr}:@" /mnt/etc/master.passwd \
			2>/dev/null
	fi
	pwd_mkdb -p -d /mnt/etc /etc/master.passwd

	# During autoinstall, add root user's public ssh key to authorized_keys.
	[[ -n "$_rootkey" ]] && (
		umask 077
		print -r -- "$_rootkey" >>/mnt/root/.ssh/authorized_keys
	)

	# Perform final steps common to both an install and an upgrade.
	finish_up
}

do_upgrade() {
	local _f

	# Get $ROOTDISK and $ROOTDEV
	get_rootinfo

	echo -n "Checking root filesystem (fsck -fp /dev/$ROOTDEV)..."
	fsck -fp /dev/$ROOTDEV >/dev/null 2>&1 || { echo "FAILED."; exit; }
	echo " OK."

	echo -n "Mounting root filesystem (mount -o ro /dev/$ROOTDEV /mnt)..."
	mount -o ro /dev/$ROOTDEV /mnt || { echo "FAILED."; exit; }
	echo " OK."

	# The fstab and myname files are required.
	for _f in /mnt/etc/{fstab,myname}; do
		[[ -f $_f ]] || { echo "No $_f!"; exit; }
		cp $_f /tmp/i/${_f##*/}
	done

	# Set system hostname and register hostname specific site set.
	hostname $(stripcom /tmp/i/myname)
	ALLSETS="$ALLSETS site$VERSION-$(hostname -s).tgz"
	export PS1='\h# '

	# Configure the network.
	enable_network

	# Fetch list of mirror servers and installer choices from previous runs.
	start_cgiinfo

	# Create a skeletal /etc/fstab which is usable for the upgrade process.
	munge_fstab

	# fsck -p non-root filesystems in /etc/fstab.
	check_fs

	# Mount filesystems in /etc/fstab.
	umount /mnt || { echo "Can't umount $ROOTDEV!"; exit; }
	mount_fs

	rm -f /mnt/bsd.upgrade /mnt/auto_upgrade.conf

	# Feed the random pool some entropy before we read from it.
	feed_random

	# Ensure that previous installer choices (e.g. method) are available.
	wait_cgiinfo

	# Ask the user for locations, and install whatever sets the user
	# selected.
	install_sets

	# Perform final steps common to both an install and an upgrade.
	finish_up
}

check_unattendedupgrade() {
	local _d=$(get_dkdevs_root) _rc=1

	_d=${_d%% *}
	(
		if [[ -n $_d ]]; then
			make_dev $_d
			if mount -t ffs -r /dev/${_d}a /mnt; then
				[[ -f /mnt/bsd.upgrade && -f /mnt/auto_upgrade.conf ]]
				_rc=$?
				((_rc == 0)) && cp /mnt/auto_upgrade.conf /
				echo "Which disk is the root disk = ${_d}" >> /auto_upgrade.conf
				umount -f /mnt
			fi
			rm -f /dev/{r,}$_d?
		fi
		return $_rc
	) > /dev/null 2>&1
}

WATCHDOG_PERIOD_SEC=$((30 * 60))

# Restart the background timer.
reset_watchdog() {
	kill -KILL $WDPID 2>/dev/null
	start_watchdog
}

# Start a co-process to reboot a stalled sysupgrade.
# This mechanism is only used during non-interactive sysupgrade.
start_watchdog() {
	(
		sleep $WATCHDOG_PERIOD_SEC && reboot
	) |&
	WDPID=$!

	# Close standard input of the co-process.
	exec 3>&p; exec 3>&-
}

# ------------------------------------------------------------------------------
# Initial actions common to both installs and upgrades.
#
# Some may require machine dependent routines, which may call functions defined
# above, so it's safest to put this code here rather than at the top.
# ------------------------------------------------------------------------------

# Parse parameters.
AI=false
UU=false
MODE=
PROGNAME=${0##*/}
AI_RESPFILE=
while getopts "af:m:x" opt; do
	case $opt in
	a)	AI=true;;
	f)	AI_RESPFILE=$OPTARG;;
	m)	MODE=$OPTARG;;
	x)	UU=true;;
	*)	usage;;
	esac
done
shift $((OPTIND-1))
(($# == 0)) || usage

# The installer can be started by using the symbolic links 'install', 'upgrade'
# and 'autoinstall' pointing to this script. Set MODE and AI based on that.
if [[ -z $MODE ]]; then
	case $PROGNAME in
	autoinstall)		AI=true;;
	install|upgrade)	MODE=$PROGNAME;;
	*)			exit 1;;
	esac
fi

# Do not limit ourselves during installs or upgrades.
for _opt in d f l m n p s; do
	ulimit -$_opt unlimited
done

# umount all filesystems, just in case we are re-running install or upgrade.
cd /
umount -af >/dev/null 2>&1

# Include machine-dependent functions and definitions.
#
# The following functions must be provided:
#	md_congrats()		  - display friendly message
#	md_installboot()	  - install boot-blocks on disk
#	md_prep_disklabel()	  - put an OpenBSD disklabel on the disk
#	md_consoleinfo()	  - set CDEV, CTTY, CSPEED, CPROM
#
# The following variables can be provided if required:
#	MDEFI       - set to 'y' on archs that support GPT partitioning
#	MDFSOPT     - newfs options for non-root partitions, '-O2' assumed if not provided
#	MDROOTFSOPT - newfs options for the root partition, '-O2' assumed if not provided
#	MDSETS	    - list of files to add to DEFAULT and ALLSETS
#	MDSANESETS  - list of files to add to SANESETS
#	MDTERM      - 'vt220' assumed if not provided
#	MDDKDEVS    - '/^[sw]d[0-9][0-9]* /s/ .*//p' assumed if not provided
#	MDCDDEVS    - '/^cd[0-9][0-9]* /s/ .*//p'    assumed if not provided
#	MDXAPERTURE - set machdep.allowaperture=value in sysctl.conf
#	MDXDM       - ask if xdm should be started if set to 'y'
#	NCPU	    - the number of cpus for mp capable arches
#	MDKERNEL    - the name of the boot kernel
#	MDHALT      - default to 'halt' at the end of installs if set to 'y'
. install.md

# Start listener process looking for dmesg changes.
start_dmesg_listener

CGI_INFO=/tmp/i/cgiinfo
CGI_METHOD=
CGI_TIME=
CGI_TZ=
export EDITOR=ed
HTTP_DIR=
HTTP_LIST=/tmp/i/httplist
HTTP_SEC=/tmp/i/httpsec
INSTALL_METHOD=
NIFS=0
export PS1="$MODE# "
PUB_KEY=/etc/signify/openbsd-${VERSION}-base.pub
ROOTDEV=
ROOTDISK=
SETDIR="$VNAME/$ARCH"
UPGRADE_BSDRD=false
V4_DHCPCONF=false
V6_AUTOCONF=false
WLANLIST=/tmp/i/wlanlist

# Save one boot's worth of dmesg.
dmesgtail >/var/run/dmesg.boot

# Are we in a real release, or a snapshot?  If this is a snapshot
# install media, default us to a snapshot directory.
HTTP_SETDIR=$SETDIR
set -- $(scan_dmesg "/^OpenBSD $VNAME\([^ ]*\).*$/s//\1/p")
[[ $1 == -!(stable) ]] && HTTP_SETDIR=snapshots/$ARCH

# Detect if ftp(1) has tls support and set defaults based on that.
if [[ -e /etc/ssl/cert.pem ]]; then
	FTP_TLS=true
	HTTP_PROTO=https
else
	FTP_TLS=false
	HTTP_PROTO=http
fi

# Scan /var/run/dmesg.boot for console device.
CONSOLE=$(scan_dmesg '/^\([^ ]*\).*: console$/s//\1/p')
[[ -n $CONSOLE ]] && CSPEED=$(stty speed </dev/console)

# Look for the serial device matching the console. If we are not installing
# from a serial console, just find the first serial device that could be used
# as a console. If a suitable device is found, set CDEV, CTTY, CSPEED, CPROM.
md_consoleinfo

# Selected sets will be installed in the order they are listed in $ALLSETS.
# Ensure that siteXX.tgz is the *last* set listed so its contents overwrite
# the contents of the other sets, not the other way around.
SETS=$(echo {base,comp,man,game,xbase,xshare,xfont,xserv}$VERSION.tgz)
DEFAULTSETS="${MDSETS:-bsd bsd.rd} $SETS"
ALLSETS="${MDSETS:-bsd bsd.rd} $SETS site$VERSION.tgz"
SANESETS="${MDSANESETS:-bsd} base${VERSION}.tgz"
if ((NCPU > 1)); then
	DEFAULTSETS="${MDSETS:-bsd bsd.mp bsd.rd} $SETS"
	ALLSETS="${MDSETS:-bsd bsd.mp bsd.rd} $SETS site$VERSION.tgz"
	SANESETS="${MDSANESETS:-bsd bsd.mp} base${VERSION}.tgz"
fi

# Prepare COLUMNS sanely.
export COLUMNS=$(stty -a </dev/console |
	sed -n '/columns/{s/^.* \([0-9]*\) columns.*$/\1/;p;}')
((COLUMNS == 0)) && COLUMNS=80

# Interactive or automatic installation?
if ! $AI; then
	cat <<__EOT
At any prompt except password prompts you can escape to a shell by
typing '!'. Default answers are shown in []'s and are selected by
pressing RETURN.  You can exit this program at any time by pressing
Control-C, but this can leave your system in an inconsistent state.

__EOT
elif $UU; then
	MODE=upgrade
	check_unattendedupgrade || exit 1

	start_watchdog

	get_responsefile
	do_autoinstall
elif [[ -z $AI_RESPFILE ]]; then
	get_responsefile ||
		err_exit "No response file found; non-interactive mode aborted."

	do_autoinstall
else
	cp $AI_RESPFILE /tmp/ai/ai.conf || exit
fi

# Configure the terminal and keyboard.
set_term

# In case of restart, delete previously logged answers.
rm -f /tmp/i/$MODE.resp

case $MODE in
install)	do_install;;
upgrade)	do_upgrade;;
esac

# In case of autoinstall, this is a second process of install.sub.
# Exiting here returns to the original process, which handles the
# automatic reboot in do_autoinstall().
$AI && exit

_d=reboot
[[ $MODE == install && $MDHALT == y ]] && _d=halt

while :; do
	ask "Exit to (S)hell, (H)alt or (R)eboot?" "$_d"
	case $resp in
	[hH]*)	exec halt;;
	[rR]*)	exec reboot;;
	[sS]*)	break;;
	esac
done

# Fall through to .profile which leaves us at the command prompt.
echo "To boot the new system, enter 'reboot' at the command prompt."