[net-next,RFC] selftests/net: integrate packetdrill with ksft

Message ID	20240827193417.2792223-1-willemdebruijn.kernel@gmail.com
State	New
Headers	show Received: from mail-oo1-f47.google.com (mail-oo1-f47.google.com [209.85.161.47]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 6E4131C6F56; Tue, 27 Aug 2024 19:34:23 +0000 (UTC) From: Willem de Bruijn <willemdebruijn.kernel@gmail.com> To: netdev@vger.kernel.org Cc: davem@davemloft.net, kuba@kernel.org, edumazet@google.com, pabeni@redhat.com, ncardwell@google.com, shuah@kernel.org, linux-kselftest@vger.kernel.org, fw@strlen.de, Willem de Bruijn <willemb@google.com> Subject: [PATCH net-next RFC] selftests/net: integrate packetdrill with ksft Date: Tue, 27 Aug 2024 15:32:29 -0400 Message-ID: <20240827193417.2792223-1-willemdebruijn.kernel@gmail.com> Precedence: bulk MIME-Version: 1.0 Content-Transfer-Encoding: 8bit
Series	[net-next,RFC] selftests/net: integrate packetdrill with ksft \| expand [net-next,RFC] selftests/net: integrate packetdrill with ksft

diff --git a/tools/testing/selftests/Makefile b/tools/testing/selftests/Makefile index a5f1c0c27dff9..f03d6fee7ac54 100644 --- a/tools/testing/selftests/Makefile +++ b/tools/testing/selftests/Makefile @@ -65,10 +65,11 @@ TARGETS += net/af_unix TARGETS += net/forwarding TARGETS += net/hsr TARGETS += net/mptcp -TARGETS += net/openvswitch -TARGETS += net/tcp_ao TARGETS += net/netfilter +TARGETS += net/openvswitch +TARGETS += net/packetdrill TARGETS += net/rds +TARGETS += net/tcp_ao TARGETS += nsfs TARGETS += perf_events TARGETS += pidfd @@ -122,7 +123,7 @@ TARGETS_HOTPLUG = cpu-hotplug TARGETS_HOTPLUG += memory-hotplug # Networking tests want the net/lib target, include it automatically -ifneq ($(filter net drivers/net drivers/net/hw,$(TARGETS)),) +ifneq ($(filter net net/packetdrill drivers/net drivers/net/hw,$(TARGETS)),) ifeq ($(filter net/lib,$(TARGETS)),) INSTALL_DEP_TARGETS := net/lib endif diff --git a/tools/testing/selftests/net/packetdrill/.gitignore b/tools/testing/selftests/net/packetdrill/.gitignore new file mode 100644 index 0000000000000..a40f1a600eb94 --- /dev/null +++ b/tools/testing/selftests/net/packetdrill/.gitignore @@ -0,0 +1 @@ +tcp*sh diff --git a/tools/testing/selftests/net/packetdrill/Makefile b/tools/testing/selftests/net/packetdrill/Makefile new file mode 100644 index 0000000000000..d94c51098d1f0 --- /dev/null +++ b/tools/testing/selftests/net/packetdrill/Makefile @@ -0,0 +1,28 @@ +# SPDX-License-Identifier: GPL-2.0 + +# KSFT includes +TEST_INCLUDES := $(wildcard lib/py/*.py ../lib/py/*.py) + +# Packetdrill support file(s) +TEST_INCLUDES += tcp/common/defaults.sh +TEST_INCLUDES += tcp/common/set_sysctls.py + +# Packetdrill scripts: all .pkt in subdirectories +TEST_INCLUDES += $(wildcard tcp/**/*.pkt) + +# Create a separate ksft test for each subdirectory +# Running all packetdrill tests in one go will take too long +# +# For each tcp/$subdir, create a test script tcp_$subdir.py +# Exclude tcp/common, which is a helper directory +TEST_DIRS := $(wildcard tcp/*) +TEST_DIRS := $(filter-out tcp/common, $(TEST_DIRS)) +TEST_CUSTOM_PROGS := $(foreach dir,$(TEST_DIRS),$(subst /,_,$(dir)).py) + +$(TEST_CUSTOM_PROGS) : packetdrill_ksft.py + cp $< $@ + +# Needed to generate all TEST_CUSTOM_PROGS +all: $(TEST_CUSTOM_PROGS) + +include ../../lib.mk diff --git a/tools/testing/selftests/net/packetdrill/lib/py/__init__.py b/tools/testing/selftests/net/packetdrill/lib/py/__init__.py new file mode 100644 index 0000000000000..51bb6dda43d65 --- /dev/null +++ b/tools/testing/selftests/net/packetdrill/lib/py/__init__.py @@ -0,0 +1,15 @@ +# SPDX-License-Identifier: GPL-2.0 + +import pathlib +import sys + +KSFT_DIR = (pathlib.Path(__file__).parent / "../../../..").resolve() + +try: + sys.path.append(KSFT_DIR.as_posix()) + from net.lib.py import * +except ModuleNotFoundError as e: + ksft_pr("Failed importing `net` library from kernel sources") + ksft_pr(str(e)) + ktap_result(True, comment="SKIP") + sys.exit(4) diff --git a/tools/testing/selftests/net/packetdrill/packetdrill_ksft.py b/tools/testing/selftests/net/packetdrill/packetdrill_ksft.py new file mode 100755 index 0000000000000..62572a5b8331c --- /dev/null +++ b/tools/testing/selftests/net/packetdrill/packetdrill_ksft.py @@ -0,0 +1,90 @@ +#!/usr/bin/env python3 +# SPDX-License-Identifier: GPL-2.0 + +"""Run packetdrill tests in the ksft harness. + + Run all packetdrill tests in a subdirectory. + Detect the relevant subdirectory from this script name. + (Because the script cannot be given arguments.) + + Run each test, for both IPv4 and IPv6. + Return a separate ksft result for each test case. +""" + +import glob +import os +import pathlib +import shutil + +from lib.py import cmd, ksft_exit, ksft_run, KsftSkipEx, NetNS + + +def test_func_builder(pktfile_path, ipv4): + """Create a function that can be passed to ksft_run.""" + + def f(): + if ipv4: + args = ("--ip_version=ipv4 " + "--local_ip=192.168.0.1 " + "--gateway_ip=192.168.0.1 " + "--netmask_ip=255.255.0.0 " + "--remote_ip=192.0.2.1 " + "-D CMSG_LEVEL_IP=SOL_IP " + "-D CMSG_TYPE_RECVERR=IP_RECVERR " + ) + else: + args = ("--ip_version=ipv6 --mtu=1520 " + "--local_ip=fd3d:0a0b:17d6::1 " + "--gateway_ip=fd3d:0a0b:17d6:8888::1 " + "--remote_ip=fd3d:fa7b:d17d::1 " + "-D CMSG_LEVEL_IP=SOL_IPV6 " + "-D CMSG_TYPE_RECVERR=IPV6_RECVERR" + ) + + if not shutil.which("packetdrill"): + raise KsftSkipEx("Cannot find packetdrill") + + netns = NetNS() + + # Call packetdrill from the directory hosting the .pkt script, + # because scripts can have relative includes. + savedir = os.getcwd() + os.chdir(os.path.dirname(pktfile_path)) + basename = os.path.basename(pktfile_path) + cmd(f"packetdrill {args} {basename}", ns=netns) + os.chdir(savedir) + + if ipv4: + f.__name__ = pathlib.Path(pktfile_path).stem + "-v4" + else: + f.__name__ = pathlib.Path(pktfile_path).stem + "-v6" + + return f + + +def scriptname_to_testdir(filepath): + """Extract the directory to run from this filename.""" + + suffix = ".sh" + + subdir = os.path.basename(filepath) + subdir = subdir[:-len(suffix)] + subdir = subdir.replace("_", "/") + return subdir + + +def main() -> None: + subdir = scriptname_to_testdir(__file__) + files = glob.glob(f"{subdir}/**/*.pkt", recursive=True) + + cases = [] + for file in files: + for ipv4 in [True, False]: + cases.append(test_func_builder(file, ipv4=ipv4)) + + ksft_run(cases=cases) + ksft_exit() + + +if __name__ == "__main__": + main() diff --git a/tools/testing/selftests/net/packetdrill/tcp/common/defaults.sh b/tools/testing/selftests/net/packetdrill/tcp/common/defaults.sh new file mode 100755 index 0000000000000..1095a7b22f44d --- /dev/null +++ b/tools/testing/selftests/net/packetdrill/tcp/common/defaults.sh @@ -0,0 +1,63 @@ +#!/bin/bash +# SPDX-License-Identifier: GPL-2.0 +# +# Set standard production config values that relate to TCP behavior. + +# Flush old cached data (fastopen cookies). +ip tcp_metrics flush all > /dev/null 2>&1 + +# TCP min, default, and max receive and send buffer sizes. +sysctl -q net.ipv4.tcp_rmem="4096 540000 $((15*1024*1024))" +sysctl -q net.ipv4.tcp_wmem="4096 $((256*1024)) 4194304" + +# TCP timestamps. +sysctl -q net.ipv4.tcp_timestamps=1 + +# TCP SYN(ACK) retry thresholds +sysctl -q net.ipv4.tcp_syn_retries=5 +sysctl -q net.ipv4.tcp_synack_retries=5 + +# TCP Forward RTO-Recovery, RFC 5682. +sysctl -q net.ipv4.tcp_frto=2 + +# TCP Selective Acknowledgements (SACK) +sysctl -q net.ipv4.tcp_sack=1 + +# TCP Duplicate Selective Acknowledgements (DSACK) +sysctl -q net.ipv4.tcp_dsack=1 + +# TCP FACK (Forward Acknowldgement) +sysctl -q net.ipv4.tcp_fack=0 + +# TCP reordering degree ("dupthresh" threshold for entering Fast Recovery). +sysctl -q net.ipv4.tcp_reordering=3 + +# TCP congestion control. +sysctl -q net.ipv4.tcp_congestion_control=cubic + +# TCP slow start after idle. +sysctl -q net.ipv4.tcp_slow_start_after_idle=0 + +# TCP RACK and TLP. +sysctl -q net.ipv4.tcp_early_retrans=4 net.ipv4.tcp_recovery=1 + +# TCP method for deciding when to defer sending to accumulate big TSO packets. +sysctl -q net.ipv4.tcp_tso_win_divisor=3 + +# TCP Explicit Congestion Notification (ECN) +sysctl -q net.ipv4.tcp_ecn=0 + +sysctl -q net.ipv4.tcp_pacing_ss_ratio=200 +sysctl -q net.ipv4.tcp_pacing_ca_ratio=120 +sysctl -q net.ipv4.tcp_notsent_lowat=4294967295 > /dev/null 2>&1 + +sysctl -q net.ipv4.tcp_fastopen=0x70403 +sysctl -q net.ipv4.tcp_fastopen_key=a1a1a1a1-b2b2b2b2-c3c3c3c3-d4d4d4d4 + +sysctl -q net.ipv4.tcp_syncookies=1 + +# Override the default qdisc on the tun device. +# Many tests fail with timing errors if the default +# is FQ and that paces their flows. +tc qdisc add dev tun0 root pfifo + diff --git a/tools/testing/selftests/net/packetdrill/tcp/common/set_sysctls.py b/tools/testing/selftests/net/packetdrill/tcp/common/set_sysctls.py new file mode 100755 index 0000000000000..5ddf456ae973a --- /dev/null +++ b/tools/testing/selftests/net/packetdrill/tcp/common/set_sysctls.py @@ -0,0 +1,38 @@ +#!/usr/bin/env python3 +# SPDX-License-Identifier: GPL-2.0 + +"""Sets sysctl values and writes a file that restores them. + +The arguments are of the form "<proc-file>=<val>" separated by spaces. +The program first reads the current value of the proc-file and creates +a shell script named "/tmp/sysctl_restore_${PACKETDRILL_PID}.sh" which +restores the values when executed. It then sets the new values. + +PACKETDRILL_PID is set by packetdrill to the pid of itself, so a .pkt +file could restore sysctls by running `/tmp/sysctl_restore_${PPID}.sh` +at the end. +""" + +import os +import subprocess +import sys + +filename = '/tmp/sysctl_restore_%s.sh' % os.environ['PACKETDRILL_PID'] + +# Open file for restoring sysctl values +restore_file = open(filename, 'w') +print('#!/bin/bash', file=restore_file) + +for a in sys.argv[1:]: + sysctl = a.split('=') + # sysctl[0] contains the proc-file name, sysctl[1] the new value + + # read current value and add restore command to file + cur_val = subprocess.check_output(['cat', sysctl[0]], universal_newlines=True) + print('echo "%s" > %s' % (cur_val.strip(), sysctl[0]), file=restore_file) + + # set new value + cmd = 'echo "%s" > %s' % (sysctl[1], sysctl[0]) + os.system(cmd) + +os.system('chmod u+x %s' % filename) diff --git a/tools/testing/selftests/net/packetdrill/tcp/inq/client.pkt b/tools/testing/selftests/net/packetdrill/tcp/inq/client.pkt new file mode 100644 index 0000000000000..8cc7798c7808f --- /dev/null +++ b/tools/testing/selftests/net/packetdrill/tcp/inq/client.pkt @@ -0,0 +1,51 @@ +// SPDX-License-Identifier: GPL-2.0 +// Test TCP_INQ and TCP_CM_INQ on the client side. +`../common/defaults.sh +` + +// Create a socket and set it to non-blocking. + 0 socket(..., SOCK_STREAM, IPPROTO_TCP) = 3 + +0 fcntl(3, F_GETFL) = 0x2 (flags O_RDWR) + +0 fcntl(3, F_SETFL, O_RDWR|O_NONBLOCK) = 0 + +// Connect to the server and enable TCP_INQ. + +0 connect(3, ..., ...) = -1 EINPROGRESS (Operation now in progress) + +0 setsockopt(3, SOL_TCP, TCP_INQ, [1], 4) = 0 + + +0 > S 0:0(0) <mss 1460,sackOK,TS val 100 ecr 0,nop,wscale 8> + +.01 < S. 0:0(0) ack 1 win 5792 <mss 1460,sackOK,TS val 700 ecr 100,nop,wscale 7> + +0 > . 1:1(0) ack 1 <nop,nop,TS val 200 ecr 700> + +// Now we have 10K of data ready on the socket. + +0 < . 1:10001(10000) ack 1 win 514 + +0 > . 1:1(0) ack 10001 <nop,nop,TS val 200 ecr 700> + +// We read 1K and we should have 9K ready to read. + +0 recvmsg(3, {msg_name(...)=..., + msg_iov(1)=[{..., 1000}], + msg_flags=0, + msg_control=[{cmsg_level=SOL_TCP, + cmsg_type=TCP_CM_INQ, + cmsg_data=9000}]}, 0) = 1000 +// We read 9K and we should have no further data ready to read. + +0 recvmsg(3, {msg_name(...)=..., + msg_iov(1)=[{..., 9000}], + msg_flags=0, + msg_control=[{cmsg_level=SOL_TCP, + cmsg_type=TCP_CM_INQ, + cmsg_data=0}]}, 0) = 9000 + +// Server sends more data and closes the connections. + +0 < F. 10001:20001(10000) ack 1 win 514 + +0 > . 1:1(0) ack 20002 <nop,nop,TS val 200 ecr 700> + +// We read 10K and we should have one "fake" byte because the connection is +// closed. + +0 recvmsg(3, {msg_name(...)=..., + msg_iov(1)=[{..., 10000}], + msg_flags=0, + msg_control=[{cmsg_level=SOL_TCP, + cmsg_type=TCP_CM_INQ, + cmsg_data=1}]}, 0) = 10000 +// Now, receive EOF. + +0 read(3, ..., 2000) = 0 diff --git a/tools/testing/selftests/net/packetdrill/tcp/inq/server.pkt b/tools/testing/selftests/net/packetdrill/tcp/inq/server.pkt new file mode 100644 index 0000000000000..fd78609087b91 --- /dev/null +++ b/tools/testing/selftests/net/packetdrill/tcp/inq/server.pkt @@ -0,0 +1,51 @@ +// SPDX-License-Identifier: GPL-2.0 +// Test TCP_INQ and TCP_CM_INQ on the server side. +`../common/defaults.sh +` + +// Initialize connection + 0 socket(..., SOCK_STREAM, IPPROTO_TCP) = 3 + +0 setsockopt(3, SOL_SOCKET, SO_REUSEADDR, [1], 4) = 0 + +0 bind(3, ..., ...) = 0 + +0 listen(3, 1) = 0 + + +0 < S 0:0(0) win 32792 <mss 1000,sackOK,nop,nop,nop,wscale 10> + +0 > S. 0:0(0) ack 1 <mss 1460,nop,nop,sackOK,nop,wscale 8> + +.01 < . 1:1(0) ack 1 win 514 + +// Accept the connection and enable TCP_INQ. + +0 accept(3, ..., ...) = 4 + +0 setsockopt(4, SOL_TCP, TCP_INQ, [1], 4) = 0 + +// Now we have 10K of data ready on the socket. + +0 < . 1:10001(10000) ack 1 win 514 + +0 > . 1:1(0) ack 10001 + +// We read 2K and we should have 8K ready to read. + +0 recvmsg(4, {msg_name(...)=..., + msg_iov(1)=[{..., 2000}], + msg_flags=0, + msg_control=[{cmsg_level=SOL_TCP, + cmsg_type=TCP_CM_INQ, + cmsg_data=8000}]}, 0) = 2000 +// We read 8K and we should have no further data ready to read. + +0 recvmsg(4, {msg_name(...)=..., + msg_iov(1)=[{..., 8000}], + msg_flags=0, + msg_control=[{cmsg_level=SOL_TCP, + cmsg_type=TCP_CM_INQ, + cmsg_data=0}]}, 0) = 8000 +// Client sends more data and closes the connections. + +0 < F. 10001:20001(10000) ack 1 win 514 + +0 > . 1:1(0) ack 20002 + +// We read 10K and we should have one "fake" byte because the connection is +// closed. + +0 recvmsg(4, {msg_name(...)=..., + msg_iov(1)=[{..., 10000}], + msg_flags=0, + msg_control=[{cmsg_level=SOL_TCP, + cmsg_type=TCP_CM_INQ, + cmsg_data=1}]}, 0) = 10000 +// Now, receive error. + +0 read(3, ..., 2000) = -1 ENOTCONN (Transport endpoint is not connected) diff --git a/tools/testing/selftests/net/packetdrill/tcp/md5/md5-only-on-client-ack.pkt b/tools/testing/selftests/net/packetdrill/tcp/md5/md5-only-on-client-ack.pkt new file mode 100644 index 0000000000000..42b712e14e562 --- /dev/null +++ b/tools/testing/selftests/net/packetdrill/tcp/md5/md5-only-on-client-ack.pkt @@ -0,0 +1,28 @@ +// SPDX-License-Identifier: GPL-2.0 +// Test what happens when client does not provide MD5 on SYN, +// but then does on the ACK that completes the three-way handshake. + +`../common/defaults.sh` + +// Establish a connection. + 0 socket(..., SOCK_STREAM, IPPROTO_TCP) = 3 + +0 setsockopt(3, SOL_SOCKET, SO_REUSEADDR, [1], 4) = 0 + +0 bind(3, ..., ...) = 0 + +0 listen(3, 1) = 0 + + +0 < S 0:0(0) win 32792 <mss 1000,sackOK,nop,nop,nop,wscale 10> + +0 > S. 0:0(0) ack 1 <mss 1460,nop,nop,sackOK,nop,wscale 8> +// Ooh, weird: client provides MD5 option on the ACK: + +.01 < . 1:1(0) ack 1 win 514 <md5 000102030405060708090a0b0c0d0e0f,nop,nop> + +.01 < . 1:1(0) ack 1 win 514 <md5 000102030405060708090a0b0c0d0e0f,nop,nop> + +// The TCP listener refcount should be 2, but on buggy kernels it can be 0: + +0 `grep " 0A " /proc/net/tcp /proc/net/tcp6 | grep ":1F90"` + +// Now here comes the legit ACK: + +.01 < . 1:1(0) ack 1 win 514 + +// Make sure the connection is OK: + +0 accept(3, ..., ...) = 4 + + +.01 write(4, ..., 1000) = 1000

[net-next,RFC] selftests/net: integrate packetdrill with ksft

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