#!/bin/ksh
#	$OpenBSD$
#
# Copyright (c) 2021 Andrew Hewus Fresh <afresh1@openbsd.org>
#
# Permission to use, copy, modify, and distribute this software for any
# purpose with or without fee is hereby granted, provided that the above
# copyright notice and this permission notice appear in all copies.
#
# THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
# WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
# MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
# ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
# WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
# ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
# OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.

set -o errexit -o pipefail -o nounset

CFILE=SHA256.sig
DESTDIR=${DESTDIR:-}
FWPATTERNS="${DESTDIR}/usr/share/misc/firmware_patterns"

VNAME=${VNAME:-$(sysctl -n kern.osrelease)}
VERSION=${VERSION:-"${VNAME%.*}${VNAME#*.}"}

HTTP_FWDIR="$VNAME"
VTYPE=$( sed -n "/^OpenBSD $VNAME\([^ ]*\).*$/s//\1/p" \
    /var/run/dmesg.boot | sed '$!d' )
[[ $VTYPE == -!(stable) ]] && HTTP_FWDIR=snapshots

FWURL=http://firmware.openbsd.org/firmware/${HTTP_FWDIR}
FWPUB_KEY=${DESTDIR}/etc/signify/openbsd-${VERSION}-fw.pub

tmpdir() {
	local _i=1 _dir

	# If we're not in the installer,
	# we have mktemp and a more hostile environment
	if [ -x /usr/bin/mktemp ]; then
		_dir=$( mktemp -d "${1}-XXXXXXXXX" )
	else
		until _dir="${1}.$_i.$RANDOM" && mkdir -- "$_dir" 2>/dev/null; do
		    ((++_i < 10000)) || return 1
		done
	fi

	echo "$_dir"
}

realpath () {
	if [ -x /usr/bin/realpath ]; then
		/usr/bin/realpath "$1"
	elif [ "$1" = "${1%/*}" ]; then
		echo "${PWD}/$1"
	else
		echo "$( cd "${1%/*}" && pwd )/${1##*/}"
	fi
}

fetch() {
	local _file=$1 _user=_file _exit

	>"$_file"
	chown "$_user" "$_file"

	# If we're not in the installer, we have su(1)
	# and doas(1) is unlikely to be configured.
	if [ -x /usr/bin/su ]; then
		/usr/bin/su -s /bin/ksh "$_user" -c \
		    "/usr/bin/ftp -D 'Get/Verify' -Vm \
		        -o '$_file' '${FWURL}/${_file}'"
		_exit="$?"
	else
		/usr/bin/doas -u "$_user" \
		    ftp -D 'Get/Verify' -Vm \
		        -o "$_file" "${FWURL}/${_file}"
		_exit="$?"
	fi

	if [ "$_exit" -ne 0 ]; then
		rm -f "$_file"
		echo "Cannot fetch $_file" >&2
		return 1
	fi

	chown root "$_file"
}

verify() {
	# On the installer we don't get sha256 -C, so fake it.
	if ! fgrep -qx "SHA256 ($1) = $( /bin/sha256 -qb "$1" )" "$CFILE"; then
		echo "Checksum test for $1 failed." >&2
		return 1
	fi
}

devices_needing_firmware() {
	local _d _m _grep _dmesgtail _last=''

	# When we're not in the installer, the dmesg.boot can
	# contain multiple boots, so only look in the last one
	_dmesgtail=$( sed -n 'H;/^OpenBSD/h;${g;p;}' /var/run/dmesg.boot )

	grep -v '^[[:space:]]*#' "$FWPATTERNS" |
	    while read -r _d _m; do
		_grep="grep"
		[ "$_last" = "$_d" ] && continue
		[ "$_m" ] || _m="^${_d}[0-9][0-9]* at "
		[ "$_m" = "${_m#^}" ] && _grep="fgrep"

		echo "$_dmesgtail" | $_grep -q "$_m" || continue
		echo "$_d"
		_last="$_d"
	done
}

firmware_filename() {
	local _f
	_f="$( sed -n "s/.*(\($1-firmware-.*\.tgz\)).*/\1/p" "$CFILE" | sed '$!d' )"
	! [ "$_f" ] && echo "Unable to find firmware for $1" >&2 && return 1
	echo "$_f"
}

firmware_devicename() {
	local _d="${1##*/}"
	_d="${_d%-firmware-*}"
	echo "$_d"
}

installed_firmware() {
	for fw in "${DESTDIR}/var/db/pkg/$1-firmware"*; do
		[ -e "$fw" ] || continue
		echo "${fw##*/}"
	done
}

add_firmware () {
	local _f="${1##*/}" _pkgdir="${DESTDIR}/var/db/pkg"
	ftp -D "Install" -Vmo- "file:${1}" |
		tar -s ",^\+,${_pkgdir}/${_f%.tgz}/+," \
		-s ",^firmware,${DESTDIR}/etc/firmware," \
		-C / -zxphf - "+*" "firmware/*"

	# TODO: Should we mark these so real fw_update can -Drepair?
	ed -s "${_pkgdir}/${_f%.tgz}/+CONTENTS" <<EOL
/^@comment pkgpath/ -1a
@option manual-installation
@option firmware
@comment install-script
.
w
EOL
}

delete_firmware() {
	local _cwd _pkg="$1" _pkgdir="${DESTDIR}/var/db/pkg"

	# TODO: Check hash for files before deleting
	echo "Uninstalling $_pkg"
	_cwd="${_pkgdir}/$_pkg"

	set -A _remove -- "${_cwd}/+CONTENTS" "${_cwd}"

	while read -r c g; do
		case $c in
		@cwd) _cwd="${DESTDIR}$g"
		  ;;
		@*) continue
		  ;;
		*) set -A _remove -- "$_cwd/$c" "${_remove[@]}"
		  ;;
		esac
	done < "${_pkgdir}/${_pkg}/+CONTENTS"

	# We specifically rm -f here because not removing files/dirs
	# is probably not worth failing over.
	for _r in "${_remove[@]}" ; do
		if [ -d "$_r" ]; then
			# Try hard not to actually remove recursively
			# without rmdir on the install media.
			[ "$_r/*" = "$( echo "$_r"/* )" ] && rm -rf "$_r"
		else
			rm -f "$_r"
		fi
	done
}

set -A devices -- "$@"

[ "${devices[*]:-}" ] ||
    set -A devices -- $( devices_needing_firmware )

if [ ! "${devices:-}" ]; then
	echo "No devices found which need firmware files to be downloaded."
	exit
fi

# Have to find the full path to firmware files
# so we can cd and still find them later.
i=0
while (( i < "${#devices[@]}" )); do
	f="${devices[$i]}"
	d=$( firmware_devicename "$f" )
	[ "$f" = "$d" ] && f="$( echo "$f"-firmware-*.tgz | sed '$!d' )"
	if [ -e "$f" ]; then
		devices[$i]="$d:$( realpath "$f" )"
	fi
	i=$((i + 1))
done

TMPDIR=$( tmpdir "${DESTDIR}/tmp/fw_install" )
cd "$TMPDIR"

# To unpriv we need to let the unpriv user into this dir
chmod go+x .

fetch "$CFILE"
! signify -qVep "$FWPUB_KEY" -x "$CFILE" -m "$CFILE" &&
    echo "Signature check of SHA256.sig failed" >&2 && exit 1

for d in "${devices[@]}"; do
	f="${d##*:}"
	if [ "$f" = "$d" ]; then
		f=$( firmware_filename "$d" || true )
		[ "$f" ] || continue
	else
	    d="${d%:*}"
	fi

	set -A installed -- $( installed_firmware "$d" )

	if [ "${installed:-}" ]; then
		for i in "${installed[@]:-}"; do
			if [ "${f##*/}" = "$i.tgz" ]; then
				echo "$i already installed"
				continue 2
			fi
		done
	fi

	if [ ! -e "$f" ]; then
		fetch  "$f" || continue
		verify "$f" || continue
	fi

	if [ "${installed:-}" ]; then
		for i in "${installed[@]}"; do
			delete_firmware "$i"
		done
	fi

	add_firmware "$f"
done