#!/bin/bash

# Hack in additional firmware directories for supported caveats.

#

# SPDX-License-Identifier: CC0-1.0

check() {

	return 0

}

install() {

	local FW_DIR=/lib/firmware

	local DATA_DIR=/usr/share/microcode_ctl/ucode_with_caveats

	local CFG_DIR="/etc/microcode_ctl/ucode_with_caveats"

	local check_caveats=/usr/libexec/microcode_ctl/check_caveats

	local verbose_opt

	local cc_out

	local path

	local ignored

	local do_skip_host_only

	local p

	verbose_opt=

	[ 4 -gt "$stdloglvl" ] || verbose_opt="-v"

	# HACK: we override external fw_dir variable in order to get

	#       an additional ucode based on the kernel version.

	dinfo "  microcode_ctl module: mangling fw_dir"

	[ -z "$fw_dir_l" ] || {

		dinfo "    microcode_ctl: avoid touching fw_dir as" \

		      "it has been changed (fw_dir_l is '$fw_dir_l')"

		return 0

	}

	# Reset fw_dir to avoid inclusion of kernel-version-specific directories

	# populated with microcode for the late load

	[ "x$fw_dir" != \

	  "x/lib/firmware/updates /lib/firmware /lib/firmware/$kernel" ] || {

		fw_dir="/lib/firmware/updates /lib/firmware"

		dinfo "    microcode_ctl: reset fw_dir to \"${fw_dir}\""

	}

	fw_dir_add=""

	while read -d $'\n' -r i; do

		dinfo "    microcode_ctl: processing data directory " \

		      "\"$DATA_DIR/$i\"..."

		if ! cc_out=$($check_caveats -e -k "$kernel" -c "$i" $verbose_opt)

		then

			dinfo "    microcode_ctl: kernel version \"$kernel\"" \

			      "failed early load check for \"$i\", skipping"

			continue

		fi

		path=$(printf "%s" "$cc_out" | sed -n 's/^paths //p')

		[ -n "$path" ] || {

			ignored=$(printf "%s" "$cc_out" | \

					sed -n 's/^skip_cfgs //p')

			if [ -n "$ignored" ]; then

				dinfo "    microcode_ctl: configuration" \

				      "\"$i\" is ignored"

			else

				dinfo "    microcode_ctl: no microcode paths" \

				      "are associated with \"$i\", skipping"

			fi

			continue

		}

		if [ "x" != "x$hostonly" ]; then

			do_skip_host_only=0

			local sho_overrides="

				$CFG_DIR/skip-host-only-check

				$CFG_DIR/skip-host-only-check-$i

				$FW_DIR/$kernel/skip-host-only-check

				$FW_DIR/$kernel/skip-host-only-check-$i"

			for p in $(echo "$sho_overrides"); do

				[ -e "$p" ] || continue

				do_skip_host_only=1

				dinfo "    microcode_ctl: $i; skipping" \

				      "Host-Only check, since \"$p\" exists."

				break

			done

		else

			do_skip_host_only=1

		fi

		if [ 0 -eq "$do_skip_host_only" ]; then

			local hostonly_passed=0

			local ucode

			local uvendor

			local ucode_dir=""

			ucode=$(get_ucode_file)

			uvendor=$(get_cpu_vendor)

			case "$uvendor" in

			Intel)

				ucode_dir="intel-ucode"

				;;

			AMD)

				ucode_dir="amd-ucode"

				;;

			*)

				dinfo "    microcode_ctl: unknown CPU" \

				      "vendor: \"$uvendor\", bailing out of" \

				      "Host-Only check"

				continue

				;;

			esac

			# $path is a list of globs, so it needs special care

			for p in $(printf "%s" "$path"); do

				# "true" is due to sporadic SIGPIPE from find

				# when "grep -q" exits early.

				{ find "$DATA_DIR/$i" -path "$DATA_DIR/$i/$p" \

					-print0; true; } \

				    | grep -zFxq \

					"$DATA_DIR/$i/$ucode_dir/$ucode" \

				    || continue

				dinfo "    microcode_ctl: $i: Host-Only" \

				      "mode is enabled and" \

				      "\"$ucode_dir/$ucode\" matches \"$p\""

				hostonly_passed=1

				break

			done

			[ 1 -eq "$hostonly_passed" ] || {

				dinfo "    microcode_ctl: $i: Host-Only mode" \

				      "is enabled and ucode name does not" \

				      "match the expected one, skipping" \

				      "caveat (\"$ucode\" not in \"$path\")"

				continue

			}

		fi

		dinfo "      microcode_ctl: $i: caveats check for kernel" \

		      "version \"$kernel\" passed, adding" \

		      "\"$DATA_DIR/$i\" to fw_dir variable"

		if [ 0 -eq "$do_skip_host_only" ]; then

			fw_dir_add="$DATA_DIR/$i "

		else

			fw_dir_add="$DATA_DIR/$i $fw_dir_add"

		fi

	# The list of directories is reverse-sorted in order to preserve the

	# "last wins" policy in case of presence of multiple microcode

	# revisions.

	#

	# In case of hostonly == 0, all microcode revisions will be included,

	# but since the microcode search is done with the "first wins" policy

	# by the (early) microcode loading code, the correct microcode revision

	# still has to be picked.

	#

	# Note that dracut without patch [1] puts only the last directory

	# in the early cpio; we try to address this by putting only the last

	# matching caveat in the search path, but that workaround works only

	# for host-only mode; non-host-only mode early cpio generation is still

	# broken without that patch.

	#

	# [1] https://github.com/dracutdevs/dracut/commit/c44d2252bb4b

	done <<-EOF

	$(find "$DATA_DIR" -maxdepth 1 -mindepth 1 -type d -printf "%f\n" \

		| LC_ALL=C sort)

	EOF

	fw_dir="${fw_dir_add}${fw_dir}"

	dinfo "    microcode_ctl: final fw_dir: \"${fw_dir}\""

}