#!/bin/bash
#
# Copyright (C) - 2016 Julien Desfossez <jdesfossez@efficios.com>
#
# This program is free software; you can redistribute it and/or modify it
# under the terms of the GNU General Public License, version 2 only, as
# published by the Free Software Foundation.
#
# This program is distributed in the hope that it will be useful, but WITHOUT
# ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
# FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
# more details.
#
# You should have received a copy of the GNU General Public License along with
# this program; if not, write to the Free Software Foundation, Inc., 51
# Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.

TEST_DESC="Kernel tracer - select, poll and epoll payload extraction"

CURDIR=$(dirname $0)/
TESTDIR=$CURDIR/../..
VALIDATE_SCRIPT="$CURDIR/validate_select_poll_epoll.py"
NUM_TESTS=102

# Only run this test on x86 and arm
uname -m | grep -E "x86|i686|arm|aarch64" >/dev/null 2>&1
if test $? != 0; then
	exit 0
fi

DISABLE_VALIDATE=0
# Babeltrace python bindings are required for the validation, but
# it is not a mandatory dependancy of the project, so fail run the
# without the content validation, at least we test that we are not
# crashing the kernel.
$VALIDATE_SCRIPT --help >/dev/null 2>&1
if test $? != 0; then
	echo "# Failed to run the validation script, Babeltrace Python bindings might be missing"
	DISABLE_VALIDATE=1
fi

LAST_WARNING=$(dmesg | grep " WARNING:" | cut -d' ' -f1 | tail -1)
LAST_OOPS=$(dmesg | grep " OOPS:" | cut -d' ' -f1 | tail -1)
LAST_BUG=$(dmesg | grep " BUG:" | cut -d' ' -f1 | tail -1)

source $TESTDIR/utils/utils.sh

function check_trace_content()
{
	if test $DISABLE_VALIDATE == 1; then
		ok 0 "Validation skipped"
		return
	fi

	$VALIDATE_SCRIPT $@
	if test $? = 0; then
		ok 0 "Validation success"
	else
		fail "Validation"
	fi
}

function test_working_cases()
{
	TRACE_PATH=$(mktemp -d)
	SESSION_NAME="syscall_payload"

	# arm64 does not have epoll_wait
	uname -m | grep -E "aarch64" >/dev/null 2>&1
	if test $? = 0; then
		SYSCALL_LIST="select,pselect6,poll,ppoll,epoll_ctl,epoll_pwait"
	else
		SYSCALL_LIST="select,pselect6,poll,ppoll,epoll_ctl,epoll_wait,epoll_pwait"
	fi

	diag "Working cases for select, pselect6, poll, ppoll and epoll, waiting for input"

	create_lttng_session_ok $SESSION_NAME $TRACE_PATH

	lttng_enable_kernel_syscall_ok $SESSION_NAME $SYSCALL_LIST
	add_context_kernel_ok $SESSION_NAME channel0 pid

	start_lttng_tracing_ok
	{ out=$(yes | $CURDIR/select_poll_epoll -t 1); } 2>/dev/null
	stop_lttng_tracing_ok
	pid=$(echo $out | cut -d' ' -f1)

	validate_trace "$SYSCALL_LIST" $TRACE_PATH
	check_trace_content -t 1 -p $pid $TRACE_PATH

	destroy_lttng_session_ok $SESSION_NAME

	rm -rf $TRACE_PATH
}

function test_timeout_cases()
{
	TRACE_PATH=$(mktemp -d)
	SESSION_NAME="syscall_payload"

	# arm64 does not have epoll_wait
	uname -m | grep -E "aarch64" >/dev/null 2>&1
	if test $? = 0; then
		SYSCALL_LIST="select,pselect6,poll,ppoll,epoll_ctl,epoll_pwait"
	else
		SYSCALL_LIST="select,pselect6,poll,ppoll,epoll_ctl,epoll_wait,epoll_pwait"
	fi

	diag "Timeout cases (1ms) for select, pselect6, poll, ppoll and epoll"

	create_lttng_session_ok $SESSION_NAME $TRACE_PATH

	lttng_enable_kernel_syscall_ok $SESSION_NAME "$SYSCALL_LIST"
	add_context_kernel_ok $SESSION_NAME channel0 pid

	start_lttng_tracing_ok
	{ out=$($CURDIR/select_poll_epoll -t 2); } 2>/dev/null
	stop_lttng_tracing_ok
	pid=$(echo $out | cut -d' ' -f1)

	validate_trace "$SYSCALL_LIST" $TRACE_PATH
	check_trace_content -t 2 -p $pid $TRACE_PATH 2>/dev/null

	destroy_lttng_session_ok $SESSION_NAME

	rm -rf $TRACE_PATH
}

function test_pselect_invalid_fd()
{
	TRACE_PATH=$(mktemp -d)
	SESSION_NAME="syscall_payload"
	SYSCALL_LIST="pselect6"

	diag "pselect with invalid FD"

	create_lttng_session_ok $SESSION_NAME $TRACE_PATH

	lttng_enable_kernel_syscall_ok $SESSION_NAME $SYSCALL_LIST
	add_context_kernel_ok $SESSION_NAME channel0 pid

	start_lttng_tracing_ok
	{ out=$($CURDIR/select_poll_epoll -t 3); } 2>/dev/null
	stop_lttng_tracing_ok
	pid=$(echo $out | cut -d' ' -f1)

	validate_trace "$SYSCALL_LIST" $TRACE_PATH
	check_trace_content -t 3 -p $pid $TRACE_PATH 2>/dev/null

	destroy_lttng_session_ok $SESSION_NAME

	rm -rf $TRACE_PATH
}

function test_big_ppoll()
{
	TRACE_PATH=$(mktemp -d)
	SESSION_NAME="syscall_payload"
	SYSCALL_LIST="ppoll"

	diag "ppoll with 2047 FDs"

	create_lttng_session_ok $SESSION_NAME $TRACE_PATH

	lttng_enable_kernel_syscall_ok $SESSION_NAME $SYSCALL_LIST
	add_context_kernel_ok $SESSION_NAME channel0 pid

	start_lttng_tracing_ok
	{ out=$(yes | $CURDIR/select_poll_epoll -t 4); } 2>/dev/null
	stop_lttng_tracing_ok
	pid=$(echo $out | cut -d' ' -f1)

	validate_trace "$SYSCALL_LIST" $TRACE_PATH
	check_trace_content -t 4 -p $pid $TRACE_PATH 2>/dev/null

	destroy_lttng_session_ok $SESSION_NAME

	rm -rf $TRACE_PATH
}

function test_ppoll_overflow()
{
	TRACE_PATH=$(mktemp -d)
	SESSION_NAME="syscall_payload"
	SYSCALL_LIST="ppoll"

	diag "ppoll buffer overflow, should segfault, waits for input"

	create_lttng_session_ok $SESSION_NAME $TRACE_PATH

	lttng_enable_kernel_syscall_ok $SESSION_NAME $SYSCALL_LIST
	add_context_kernel_ok $SESSION_NAME channel0 pid

	start_lttng_tracing_ok
	diag "Expect segfaults"
	{ out=$(yes | $CURDIR/select_poll_epoll -t 5); } 2>/dev/null
	stop_lttng_tracing_ok
	echo $out
	pid=$(echo $out | cut -d' ' -f1)

	validate_trace "$SYSCALL_LIST" $TRACE_PATH

	check_trace_content -t 5 -p $pid $TRACE_PATH 2>/dev/null

	destroy_lttng_session_ok $SESSION_NAME

	rm -rf $TRACE_PATH
}

function test_pselect_invalid_ptr()
{
	TRACE_PATH=$(mktemp -d)
	SESSION_NAME="syscall_payload"
	SYSCALL_LIST="pselect6"

	diag "pselect with invalid pointer, waits for input"

	create_lttng_session_ok $SESSION_NAME $TRACE_PATH

	lttng_enable_kernel_syscall_ok $SESSION_NAME $SYSCALL_LIST
	add_context_kernel_ok $SESSION_NAME channel0 pid

	start_lttng_tracing_ok
	{ out=$(yes | $CURDIR/select_poll_epoll -t 6); } 2>/dev/null
	stop_lttng_tracing_ok
	pid=$(echo $out | cut -d' ' -f1)

	validate_trace "$SYSCALL_LIST" $TRACE_PATH
	check_trace_content -t 6 -p $pid $TRACE_PATH 2>/dev/null

	destroy_lttng_session_ok $SESSION_NAME

	rm -rf $TRACE_PATH
}

function test_ppoll_ulong_max()
{
	TRACE_PATH=$(mktemp -d)
	SESSION_NAME="syscall_payload"
	SYSCALL_LIST="ppoll"

	diag "ppoll with ulong_max fds, waits for input"

	create_lttng_session_ok $SESSION_NAME $TRACE_PATH

	lttng_enable_kernel_syscall_ok $SESSION_NAME $SYSCALL_LIST
	add_context_kernel_ok $SESSION_NAME channel0 pid

	start_lttng_tracing_ok
	{ out=$(yes | $CURDIR/select_poll_epoll -t 7); } 2>/dev/null
	stop_lttng_tracing_ok
	pid=$(echo $out | cut -d' ' -f1)

	validate_trace "$SYSCALL_LIST" $TRACE_PATH
	check_trace_content -t 7 -p $pid $TRACE_PATH 2>/dev/null

	destroy_lttng_session_ok $SESSION_NAME

	rm -rf $TRACE_PATH
}

function test_epoll_pwait_invalid_ptr()
{
	TRACE_PATH=$(mktemp -d)
	SESSION_NAME="syscall_payload"
	SYSCALL_LIST="epoll_pwait"

	diag "epoll_pwait with invalid pointer, waits for input"

	create_lttng_session_ok $SESSION_NAME $TRACE_PATH

	lttng_enable_kernel_syscall_ok $SESSION_NAME $SYSCALL_LIST
	add_context_kernel_ok $SESSION_NAME channel0 pid

	start_lttng_tracing_ok
	{ out=$(yes | $CURDIR/select_poll_epoll -t 8); } 2>/dev/null
	stop_lttng_tracing_ok
	pid=$(echo $out | cut -d' ' -f1)

	validate_trace "$SYSCALL_LIST" $TRACE_PATH
	check_trace_content -t 8 -p $pid $TRACE_PATH 2>/dev/null

	destroy_lttng_session_ok $SESSION_NAME

	rm -rf $TRACE_PATH
}

function test_epoll_pwait_int_max()
{
	TRACE_PATH=$(mktemp -d)
	SESSION_NAME="syscall_payload"
	SYSCALL_LIST="epoll_pwait"

	diag "epoll_pwait with maxevents set to INT_MAX, waits for input"

	create_lttng_session_ok $SESSION_NAME $TRACE_PATH

	lttng_enable_kernel_syscall_ok $SESSION_NAME $SYSCALL_LIST
	add_context_kernel_ok $SESSION_NAME channel0 pid

	start_lttng_tracing_ok
	{ out=$(yes | $CURDIR/select_poll_epoll -t 9); } 2>/dev/null
	stop_lttng_tracing_ok
	pid=$(echo $out | cut -d' ' -f1)

	validate_trace "$SYSCALL_LIST" $TRACE_PATH
	check_trace_content -t 9 -p $pid $TRACE_PATH 2>/dev/null

	destroy_lttng_session_ok $SESSION_NAME

	rm -rf $TRACE_PATH
}

function test_ppoll_concurrent()
{
	TRACE_PATH=$(mktemp -d)
	SESSION_NAME="syscall_payload"
	SYSCALL_LIST="ppoll"

	diag "ppoll with concurrent updates of the structure from user-space, stress test (3000 iterations), waits for input + timeout 1ms"

	create_lttng_session_ok $SESSION_NAME $TRACE_PATH

	lttng_enable_kernel_syscall_ok $SESSION_NAME $SYSCALL_LIST
	add_context_kernel_ok $SESSION_NAME channel0 pid

	start_lttng_tracing_ok
	{ out=$(yes | $CURDIR/select_poll_epoll -t 10); } 2>/dev/null
	stop_lttng_tracing_ok
	pid=$(echo $out | cut -d' ' -f1)

	validate_trace "$SYSCALL_LIST" $TRACE_PATH
	check_trace_content -t 10 -p $pid $TRACE_PATH 2>/dev/null

	destroy_lttng_session_ok $SESSION_NAME

	rm -rf $TRACE_PATH
}

function test_epoll_pwait_concurrent()
{
	TRACE_PATH=$(mktemp -d)
	SESSION_NAME="syscall_payload"
	SYSCALL_LIST="epoll_ctl,epoll_pwait"

	diag "epoll_pwait with concurrent munmap of the buffer from user-space, should randomly segfault, run multiple times, waits for input + timeout 1ms"

	create_lttng_session_ok $SESSION_NAME $TRACE_PATH

	lttng_enable_kernel_syscall_ok $SESSION_NAME $SYSCALL_LIST
	add_context_kernel_ok $SESSION_NAME channel0 pid

	start_lttng_tracing_ok
	diag "Expect segfaults"
	for i in $(seq 1 100); do
		{ out=$($CURDIR/select_poll_epoll -t 11); } 2>/dev/null
	done
	pid=$(echo $out | cut -d' ' -f1)
	stop_lttng_tracing_ok

	# epoll_wait is not always generated in the trace (stress test)
	validate_trace "epoll_ctl" $TRACE_PATH
	check_trace_content -t 11 -p $pid $TRACE_PATH 2>/dev/null

	destroy_lttng_session_ok $SESSION_NAME

	rm -rf $TRACE_PATH
}

# MUST set TESTDIR before calling those functions
plan_tests $NUM_TESTS

print_test_banner "$TEST_DESC"

if [ "$(id -u)" == "0" ]; then
	isroot=1
else
	isroot=0
fi

skip $isroot "Root access is needed. Skipping all tests." $NUM_TESTS ||
{
	start_lttng_sessiond

	test_working_cases
	test_timeout_cases
	test_pselect_invalid_fd
	test_big_ppoll
	test_ppoll_overflow
	test_pselect_invalid_ptr
	test_ppoll_ulong_max
	test_epoll_pwait_invalid_ptr
	test_epoll_pwait_int_max
	test_ppoll_concurrent
	test_epoll_pwait_concurrent

	stop_lttng_sessiond

	NEW_WARNING=$(dmesg | grep " WARNING:" | cut -d' ' -f1 | tail -1)
	NEW_OOPS=$(dmesg | grep " OOPS:" | cut -d' ' -f1 | tail -1)
	NEW_BUG=$(dmesg | grep " BUG:" | cut -d' ' -f1 | tail -1)

	if test "$LAST_WARNING" != "$NEW_WARNING"; then
		fail "New WARNING generated"
	fi
	if test "$LAST_OOPS" != "$NEW_OOPS"; then
		fail "New OOPS generated"
	fi
	if test "$LAST_BUG" != "$NEW_BUG"; then
		fail "New BUG generated"
	fi
}