Commit 31611cea authored by Jakub Kicinski's avatar Jakub Kicinski
Browse files

selftests: drv-net: add a TCP ping test case (and useful helpers) 



More complex tests often have to spawn a background process,
like a server which will respond to requests or tcpdump.

Add support for creating such processes using the with keyword:

  with bkg("my-daemon", ..):
     # my-daemon is alive in this block

My initial thought was to add this support to cmd() directly
but it runs the command in the constructor, so by the time
we __enter__ it's too late to make sure we used "background=True".

Second useful helper transplanted from net_helper.sh is
wait_port_listen().

The test itself uses socat, which insists on v6 addresses
being wrapped in [], it's not the only command which requires
this format, so add the wrapped address to env. The hope
is to save test code from checking if address is v6.

Reviewed-by: default avatarWillem de Bruijn <willemb@google.com>
Link: https://lore.kernel.org/r/20240420025237.3309296-7-kuba@kernel.org


Signed-off-by: default avatarJakub Kicinski <kuba@kernel.org>
parent 01b43164

tools/testing/selftests/drivers/net/lib/py/env.py

+5 −0
Original line number Diff line number Diff line
@@ -110,6 +110,11 @@ class NetDrvEpEnv: 
        self.addr = self.v6 if self.v6 else self.v4

        self.remote_addr = self.remote_v6 if self.remote_v6 else self.remote_v4



        self.addr_ipver = "6" if self.v6 else "4"

        # Bracketed addresses, some commands need IPv6 to be inside []

        self.baddr = f"[{self.v6}]" if self.v6 else self.v4

        self.remote_baddr = f"[{self.remote_v6}]" if self.remote_v6 else self.remote_v4



        self.ifname = self.dev['ifname']

        self.ifindex = self.dev['ifindex']

tools/testing/selftests/drivers/net/ping.py

+20 −1
Original line number Diff line number Diff line
@@ -2,8 +2,9 @@ 
# SPDX-License-Identifier: GPL-2.0



from lib.py import ksft_run, ksft_exit

from lib.py import ksft_eq

from lib.py import NetDrvEpEnv

from lib.py import cmd

from lib.py import bkg, cmd, wait_port_listen, rand_port





def test_v4(cfg) -> None:
@@ -16,6 +17,24 @@ def test_v6(cfg) -> None: 
    cmd(f"ping -c 1 -W0.5 {cfg.v6}", host=cfg.remote)





def test_tcp(cfg) -> None:

    port = rand_port()

    listen_cmd = f"socat -{cfg.addr_ipver} -t 2 -u TCP-LISTEN:{port},reuseport STDOUT"



    with bkg(listen_cmd, exit_wait=True) as nc:

        wait_port_listen(port)



        cmd(f"echo ping | socat -t 2 -u STDIN TCP:{cfg.baddr}:{port}",

            shell=True, host=cfg.remote)

    ksft_eq(nc.stdout.strip(), "ping")



    with bkg(listen_cmd, host=cfg.remote, exit_wait=True) as nc:

        wait_port_listen(port, host=cfg.remote)



        cmd(f"echo ping | socat -t 2 -u STDIN TCP:{cfg.remote_baddr}:{port}", shell=True)

    ksft_eq(nc.stdout.strip(), "ping")





def main() -> None:

    with NetDrvEpEnv(__file__) as cfg:

        ksft_run(globs=globals(), case_pfx={"test_"}, args=(cfg, ))

tools/testing/selftests/net/lib/py/utils.py

+43 −0
Original line number Diff line number Diff line 
# SPDX-License-Identifier: GPL-2.0



import json as _json

import random

import re

import subprocess

import time





class cmd:

    def __init__(self, comm, shell=True, fail=True, ns=None, background=False, host=None):
@@ -38,6 +42,20 @@ class cmd: 
                            (self.proc.args, stdout, stderr))





class bkg(cmd):

    def __init__(self, comm, shell=True, fail=True, ns=None, host=None,

                 exit_wait=False):

        super().__init__(comm, background=True,

                         shell=shell, fail=fail, ns=ns, host=host)

        self.terminate = not exit_wait



    def __enter__(self):

        return self



    def __exit__(self, ex_type, ex_value, ex_tb):

        return self.process(terminate=self.terminate)





def ip(args, json=None, ns=None, host=None):

    cmd_str = "ip "

    if json:
@@ -47,3 +65,28 @@ def ip(args, json=None, ns=None, host=None): 
    if json:

        return _json.loads(cmd_obj.stdout)

    return cmd_obj





def rand_port():

    """

    Get unprivileged port, for now just random, one day we may decide to check if used.

    """

    return random.randint(1024, 65535)





def wait_port_listen(port, proto="tcp", ns=None, host=None, sleep=0.005, deadline=5):

    end = time.monotonic() + deadline



    pattern = f":{port:04X} .* "

    if proto == "tcp": # for tcp protocol additionally check the socket state

        pattern += "0A"

    pattern = re.compile(pattern)



    while True:

        data = cmd(f'cat /proc/net/{proto}*', ns=ns, host=host, shell=True).stdout

        for row in data.split("\n"):

            if pattern.search(row):

                return

        if time.monotonic() > end:

            raise Exception("Waiting for port listen timed out")

        time.sleep(sleep)