#!/bin/bash

. lib.sh

#
# *** Description ***
#
# generate primary header with luks2 keyslot kdf object
# having left over params.
#
# secondary header is corrupted on purpose as well
#

# $1 full target dir
# $2 full source luks2 image

function prepare()
{
	cp $SRC_IMG $TGT_IMG
	test -d $TMPDIR || mkdir $TMPDIR
	read_luks2_json0 $TGT_IMG $TMPDIR/json0
	read_luks2_bin_hdr0 $TGT_IMG $TMPDIR/hdr0
	read_luks2_bin_hdr1 $TGT_IMG $TMPDIR/hdr1
}

function generate()
{
	# add keyslot 1 to second digest
	obj_len=$(jq -c -M '.keyslots."1".kdf | length' $TMPDIR/json0)
	json_str=$(jq -r -c -M '.keyslots."1".kdf.type = "pbkdf2" | .keyslots."1".kdf.iterations = 1001 | .keyslots."1".kdf.hash = "sha256"' $TMPDIR/json0)
	test ${#json_str} -lt $((LUKS2_JSON_SIZE*512)) || exit 2

	write_luks2_json "$json_str" $TMPDIR/json0

	merge_bin_hdr_with_json $TMPDIR/hdr0 $TMPDIR/json0 $TMPDIR/area0
	erase_checksum $TMPDIR/area0
	chks0=$(calc_sha256_checksum_file $TMPDIR/area0)
	write_checksum $chks0 $TMPDIR/area0
	write_luks2_hdr0 $TMPDIR/area0 $TGT_IMG
	kill_bin_hdr $TMPDIR/hdr1
	write_luks2_hdr1 $TMPDIR/hdr1 $TGT_IMG
}

function check()
{
	read_luks2_bin_hdr1 $TGT_IMG $TMPDIR/hdr_res1
	local str_res1=$(head -c 6 $TMPDIR/hdr_res1)
	test "$str_res1" = "VACUUM" || exit 2

	read_luks2_json0 $TGT_IMG $TMPDIR/json_res0
	chks_res0=$(read_sha256_checksum $TGT_IMG)
	test "$chks0" = "$chks_res0" || exit 2
	new_obj_len=$(jq -c -M '.keyslots."1".kdf | length' $TMPDIR/json_res0)
	test $((obj_len+2)) -eq $new_obj_len || exit 2
}

function cleanup()
{
	rm -f $TMPDIR/*
	rm -fd $TMPDIR
}

test $# -eq 2 || exit 1

TGT_IMG=$1/$(test_img_name $0)
SRC_IMG=$2

prepare
generate
check
cleanup