#!/bin/bash
# SPDX-License-Identifier: GPL-2.0
# Copyright (c) 2021 Google, Inc. All Rights Reserved.
#
# FS QA Test No. 048
#
# Test wiping of ext4_dir_entry2 data upon file removal, conversion
# to htree, and splitting of htree nodes
#
. ./common/preamble
_begin_fstest auto quick dir

# Import common functions.
. ./common/filter

# real QA test starts here
_supported_fs ext4

_require_scratch
_require_command "$DEBUGFS_PROG" debugfs

big_endian=$(echo -ne '\x11' | od -tx2 | head -1 | cut -f2 -d' ' | cut -c1)
if (( big_endian )); then
	_require_od_endian_flag
fi

testdir="${SCRATCH_MNT}/testdir"

# get block number filename's dir ent
# argument 1: filename
get_block() {
	echo $($DEBUGFS_PROG $SCRATCH_DEV -R "dirsearch /testdir $1" 2>> $seqres.full | grep -o -m 1 "phys [0-9]\+" | cut -c 6-)
}

# get offset of filename's dirent within the block
# argument 1: filename
get_offset() {
	echo $($DEBUGFS_PROG $SCRATCH_DEV -R "dirsearch /testdir $1" 2>> $seqres.full | grep -o -m 1 "offset [0-9]\+" | cut -c 8-)
}

# get record length of dir ent at specified block and offset
# argument 1: block
# argument 2: offset
get_reclen() {
	if (( big_endian )); then
		echo $(od $SCRATCH_DEV --skip-bytes=$(($1 * $blocksize + $2 + 4)) --read-bytes=2  -d -An  --endian=little | \
			tr -d ' \t\n\r')
	else
		echo $(od $SCRATCH_DEV --skip-bytes=$(($1 * $blocksize + $2 + 4)) --read-bytes=2  -d -An | \
			tr -d ' \t\n\r')
	fi
}

# reads portion of dirent that should be zero'd out (starting at offset of name_len = 6)
# and trims 0s and whitespace
# argument 1: block num containing dir ent
# argument 2: offset of dir ent within block
# argument 3: rec len of dir ent
read_dir_ent() {
	echo $(od $SCRATCH_DEV --skip-bytes=$(($1 * $blocksize + $2 + 6)) --read-bytes=$(($3 - 6)) -d -An -v | sed -e 's/[0 \t\n\r]//g')
}

# forces node split on test directory
# can be used to convert to htree and to split node on existing htree
# looks for jump in directory size as indicator of node split
induce_node_split() {
	_scratch_mount >> $seqres.full 2>&1
	dir_size="$(stat --printf="%s" $testdir)"
	while [[ "$(stat --printf="%s" $testdir)" == "$dir_size" ]]; do
		file_num=$(($file_num + 1))
		touch $testdir/test"$(printf "%04d" $file_num)"
	done
	_scratch_unmount >> $seqres.full 2>&1
}

#
# TEST 1: dir entry fields wiped upon file removal
#

test_file1="test0001"
test_file2="test0002"
test_file3="test0003"

_scratch_mkfs_sized $((128 * 1024 * 1024)) >> $seqres.full 2>&1

# create scratch dir for testing
# create some files with no name a substr of another name so we can grep later
_scratch_mount >> $seqres.full 2>&1

# Use the presence of the journal checkpoint ioctl as a proxy of filename
# wipe being supported
if test -x $here/src/checkpoint_journal && \
	! $here/src/checkpoint_journal $SCRATCH_MNT --dry-run ; then
    _notrun "filename wipe not supported"
fi

blocksize="$(_get_block_size $SCRATCH_MNT)"
mkdir $testdir
file_num=1
for file_num in {1..10}; do
	touch $testdir/test"$(printf "%04d" $file_num)"
done
_scratch_unmount >> $seqres.full 2>&1

# get block, offset, and rec_len of two test files
block1=$(get_block $test_file1)
offset1=$(get_offset $test_file1)
rec_len1=$(get_reclen $block1 $offset1)

block2=$(get_block $test_file2)
offset2=$(get_offset $test_file2)
rec_len2=$(get_reclen $block2 $offset2)

_scratch_mount >> $seqres.full 2>&1
rm $testdir/$test_file1
_scratch_unmount >> $seqres.full 2>&1

# read name_len field to end of dir entry
check1=$(read_dir_ent $block1 $offset1 $rec_len1)
check2=$(read_dir_ent $block2 $offset2 $rec_len2)

# if check is empty, bytes read was all 0's, file data wiped
# at this point, check1 should be empty, but check 2 should not be
if [ -z "$check1" ] && [ ! -z "$check2" ]; then
	echo "Test 1 part 1 passed."
else
	_fail "ERROR (test 1 part 1): metadata not wiped upon removing test file 1"
fi

_scratch_mount >> $seqres.full 2>&1
rm $testdir/$test_file2
_scratch_unmount >> $seqres.full 2>&1

check2=$(read_dir_ent $block2 $offset2 $rec_len2)

# at this point, both should be wiped
[ -z "$check2" ] && echo "Test 1 part 2 passed." || _fail "ERROR (test 1 part 2): metadata not wiped upon removing test file 2"

#
# TEST 2: old dir entry fields wiped when directory converted to htree
#

# get original location
block1=$(get_block $test_file3)
offset1=$(get_offset $test_file3)
rec_len1=$(get_reclen $block1 $offset1)

# sanity check, ensures not an htree yet
check_htree=$($DEBUGFS_PROG $SCRATCH_DEV -R "htree_dump /testdir" 2>&1)
if [[ "$check_htree" != *"htree_dump: Not a hash-indexed directory"* ]]; then
	_fail "ERROR (test 2): already an htree"
fi

# force conversion to htree
induce_node_split

# ensure it is now an htree
check_htree=$($DEBUGFS_PROG $SCRATCH_DEV -R "htree_dump /testdir" 2>&1)
if [[ "$check_htree" == *"htree_dump: Not a hash-indexed directory"* ]]; then
	_fail "ERROR (test 2): directory was not converted to an htree after creation of many files"
fi

# check that old data was wiped
# (this location is not immediately reused by ext4)
check1=$(read_dir_ent $block1 $offset1 $rec_len1)

# at this point, check1 should be empty meaning data was wiped
[ -z "$check1" ] &&  echo "Test 2 passed." || _fail "ERROR (test 2): file metadata not wiped during conversion to htree"

#
# TEST 3: old dir entries wiped when moved to another block during split_node
#

# force splitting of a node
induce_node_split
# use debugfs to get names of two files from block 3
hdump=$($DEBUGFS_PROG $SCRATCH_DEV -R "htree_dump /testdir" 2>> $seqres.full)

# get line number of "Reading directory block 3"
block3_line=$(echo "$hdump" | awk '/Reading directory block 3/{ print NR; exit }')

[ -z "$block3_line" ] && echo "ERROR (test 3): could not find block number 3 after node split"

test_file1=$(echo "$hdump" | sed -n "$(($block3_line + 1))"p | cut -d ' ' -f4)
test_file2=$(echo "$hdump" | sed -n "$(($block3_line + 2))"p | cut -d ' ' -f4)

# check these filenames don't exist in block 1 or 2
# get block numbers of first two blocks
block1=$(echo "$hdump" | grep -o -m 1 "Reading directory block 1, phys [0-9]\+" | cut -c 33-)
block2=$(echo "$hdump" | grep -o -m 1 "Reading directory block 2, phys [0-9]\+" | cut -c 33-)

# search all of both these blocks for these file names
check1=$(od $SCRATCH_DEV --skip-bytes=$(($block1 * $blocksize)) --read-bytes=$blocksize -c -An -v | tr -d '\\ \t\n\r\v' | grep -e $test_file1 -e $test_file2)
check2=$(od $SCRATCH_DEV --skip-bytes=$(($block2 * $blocksize)) --read-bytes=$blocksize -c -An -v | tr -d '\\ \t\n\r\v' | grep -e $test_file1 -e $test_file2)

if [ -z "$check1" ] && [ -z "$check2" ]; then
	echo "Test 3 passed."
else
	_fail "ERROR (test 3): file name not wiped during node split"
fi

status=0
exit