diff mbox series

[net-next,v3,8/8] selftests: drv-net: add a TCP ping test case (and useful helpers)

Message ID 20240417231146.2435572-9-kuba@kernel.org (mailing list archive)
State New
Headers show
Series selftests: drv-net: support testing with a remote system | expand

Commit Message

Jakub Kicinski April 17, 2024, 11:11 p.m. UTC
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().

Signed-off-by: Jakub Kicinski <kuba@kernel.org>
---
 tools/testing/selftests/drivers/net/ping.py | 24 +++++++++++++--
 tools/testing/selftests/net/lib/py/utils.py | 33 +++++++++++++++++++++
 2 files changed, 55 insertions(+), 2 deletions(-)

Comments

Willem de Bruijn April 18, 2024, 2:44 p.m. UTC | #1
Jakub Kicinski wrote:
> 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().
> 
> Signed-off-by: Jakub Kicinski <kuba@kernel.org>
> ---
>  tools/testing/selftests/drivers/net/ping.py | 24 +++++++++++++--
>  tools/testing/selftests/net/lib/py/utils.py | 33 +++++++++++++++++++++
>  2 files changed, 55 insertions(+), 2 deletions(-)
> 
> diff --git a/tools/testing/selftests/drivers/net/ping.py b/tools/testing/selftests/drivers/net/ping.py
> index 58aefd3e740f..8532e3be72ba 100755
> --- a/tools/testing/selftests/drivers/net/ping.py
> +++ b/tools/testing/selftests/drivers/net/ping.py
> @@ -1,9 +1,12 @@
>  #!/usr/bin/env python3
>  # SPDX-License-Identifier: GPL-2.0
>  
> -from lib.py import ksft_run, ksft_exit, KsftXfailEx
> +import random
> +
> +from lib.py import ksft_run, ksft_exit
> +from lib.py import ksft_eq, KsftXfailEx
>  from lib.py import NetDrvEpEnv
> -from lib.py import cmd
> +from lib.py import bkg, cmd, wait_port_listen
>  
>  
>  def test_v4(cfg) -> None:
> @@ -22,6 +25,23 @@ from lib.py import cmd
>      cmd(f"ping -c 1 -W0.5 {cfg.v6}", host=cfg.remote)
>  
>  
> +def test_tcp(cfg) -> None:
> +    port = random.randrange(1024 + (1 << 15))
> +    with bkg(f"nc -l {cfg.addr} {port}") as nc:
> +        wait_port_listen(port)
> +
> +        cmd(f"echo ping | nc {cfg.addr} {port}",
> +            shell=True, host=cfg.remote)
> +    ksft_eq(nc.stdout.strip(), "ping")
> +
> +    port = random.randrange(1024 + (1 << 15))
> +    with bkg(f"nc -l {cfg.remote_addr} {port}", host=cfg.remote) as nc:
> +        wait_port_listen(port, host=cfg.remote)
> +
> +        cmd(f"echo ping | nc {cfg.remote_addr} {port}", shell=True)
> +    ksft_eq(nc.stdout.strip(), "ping")
> +

There are different netcat implementations floating around.

I notice that I have to pass -N on the client to terminate the
connection after EOF. Else both peers keep the connection open,
waiting for input. And explicitly pass -6 if passing an IPv6
address. I think this is the one that ships with Debian..
Jakub Kicinski April 18, 2024, 7:48 p.m. UTC | #2
On Thu, 18 Apr 2024 10:44:39 -0400 Willem de Bruijn wrote:
> > +def test_tcp(cfg) -> None:
> > +    port = random.randrange(1024 + (1 << 15))
> > +    with bkg(f"nc -l {cfg.addr} {port}") as nc:
> > +        wait_port_listen(port)
> > +
> > +        cmd(f"echo ping | nc {cfg.addr} {port}",
> > +            shell=True, host=cfg.remote)
> > +    ksft_eq(nc.stdout.strip(), "ping")
> > +
> > +    port = random.randrange(1024 + (1 << 15))
> > +    with bkg(f"nc -l {cfg.remote_addr} {port}", host=cfg.remote) as nc:
> > +        wait_port_listen(port, host=cfg.remote)
> > +
> > +        cmd(f"echo ping | nc {cfg.remote_addr} {port}", shell=True)
> > +    ksft_eq(nc.stdout.strip(), "ping")
> > +  
> 
> There are different netcat implementations floating around.
> 
> I notice that I have to pass -N on the client to terminate the
> connection after EOF. Else both peers keep the connection open,
> waiting for input. And explicitly pass -6 if passing an IPv6
> address. I think this is the one that ships with Debian..

Right, 100% laziness on my part. Mostly because socat requires
bracketed IPv6. But once I tried it I also run into the premature
termination problem, so ended up with this diff on top:

diff --git a/tools/testing/selftests/drivers/net/lib/py/env.py b/tools/testing/selftests/drivers/net/lib/py/env.py
index 579c5b34e6fd..2f62270d59fa 100644
--- a/tools/testing/selftests/drivers/net/lib/py/env.py
+++ b/tools/testing/selftests/drivers/net/lib/py/env.py
@@ -110,6 +110,10 @@ from .remote import Remote
         self.addr = self.v6 if self.v6 else self.v4
         self.remote_addr = self.remote_v6 if self.remote_v6 else self.remote_v4
 
+        # 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']
 
diff --git a/tools/testing/selftests/drivers/net/ping.py b/tools/testing/selftests/drivers/net/ping.py
index 8532e3be72ba..985b06ce2e81 100755
--- a/tools/testing/selftests/drivers/net/ping.py
+++ b/tools/testing/selftests/drivers/net/ping.py
@@ -27,18 +27,20 @@ from lib.py import bkg, cmd, wait_port_listen
 
 def test_tcp(cfg) -> None:
     port = random.randrange(1024 + (1 << 15))
-    with bkg(f"nc -l {cfg.addr} {port}") as nc:
+
+    with bkg(f"socat -t 2 -u TCP-LISTEN:{port} STDOUT", exit_wait=True) as nc:
         wait_port_listen(port)
 
-        cmd(f"echo ping | nc {cfg.addr} {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")
 
     port = random.randrange(1024 + (1 << 15))
-    with bkg(f"nc -l {cfg.remote_addr} {port}", host=cfg.remote) as nc:
+    with bkg(f"socat -t 2 -u TCP-LISTEN:{port} STDOUT", host=cfg.remote,
+             exit_wait=True) as nc:
         wait_port_listen(port, host=cfg.remote)
 
-        cmd(f"echo ping | nc {cfg.remote_addr} {port}", shell=True)
+        cmd(f"echo ping | socat -t 2 -u STDIN TCP:{cfg.remote_baddr}:{port}", shell=True)
     ksft_eq(nc.stdout.strip(), "ping")
 
 
diff --git a/tools/testing/selftests/net/lib/py/utils.py b/tools/testing/selftests/net/lib/py/utils.py
index 6bacdc99d21b..85a6a9bb35fd 100644
--- a/tools/testing/selftests/net/lib/py/utils.py
+++ b/tools/testing/selftests/net/lib/py/utils.py
@@ -42,15 +42,17 @@ import time
 
 
 class bkg(cmd):
-    def __init__(self, comm, shell=True, fail=True, ns=None, host=None):
+    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()
+        return self.process(terminate=self.terminate)
 
 
 def ip(args, json=None, ns=None, host=None):
diff mbox series

Patch

diff --git a/tools/testing/selftests/drivers/net/ping.py b/tools/testing/selftests/drivers/net/ping.py
index 58aefd3e740f..8532e3be72ba 100755
--- a/tools/testing/selftests/drivers/net/ping.py
+++ b/tools/testing/selftests/drivers/net/ping.py
@@ -1,9 +1,12 @@ 
 #!/usr/bin/env python3
 # SPDX-License-Identifier: GPL-2.0
 
-from lib.py import ksft_run, ksft_exit, KsftXfailEx
+import random
+
+from lib.py import ksft_run, ksft_exit
+from lib.py import ksft_eq, KsftXfailEx
 from lib.py import NetDrvEpEnv
-from lib.py import cmd
+from lib.py import bkg, cmd, wait_port_listen
 
 
 def test_v4(cfg) -> None:
@@ -22,6 +25,23 @@  from lib.py import cmd
     cmd(f"ping -c 1 -W0.5 {cfg.v6}", host=cfg.remote)
 
 
+def test_tcp(cfg) -> None:
+    port = random.randrange(1024 + (1 << 15))
+    with bkg(f"nc -l {cfg.addr} {port}") as nc:
+        wait_port_listen(port)
+
+        cmd(f"echo ping | nc {cfg.addr} {port}",
+            shell=True, host=cfg.remote)
+    ksft_eq(nc.stdout.strip(), "ping")
+
+    port = random.randrange(1024 + (1 << 15))
+    with bkg(f"nc -l {cfg.remote_addr} {port}", host=cfg.remote) as nc:
+        wait_port_listen(port, host=cfg.remote)
+
+        cmd(f"echo ping | nc {cfg.remote_addr} {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, ))
diff --git a/tools/testing/selftests/net/lib/py/utils.py b/tools/testing/selftests/net/lib/py/utils.py
index e80fea9f6562..6bacdc99d21b 100644
--- a/tools/testing/selftests/net/lib/py/utils.py
+++ b/tools/testing/selftests/net/lib/py/utils.py
@@ -1,7 +1,10 @@ 
 # SPDX-License-Identifier: GPL-2.0
 
 import json as _json
+import re
 import subprocess
+import time
+
 
 class cmd:
     def __init__(self, comm, shell=True, fail=True, ns=None, background=False, host=None):
@@ -38,6 +41,18 @@  import subprocess
                             (self.proc.args, stdout, stderr))
 
 
+class bkg(cmd):
+    def __init__(self, comm, shell=True, fail=True, ns=None, host=None):
+        super().__init__(comm, background=True,
+                         shell=shell, fail=fail, ns=ns, host=host)
+
+    def __enter__(self):
+        return self
+
+    def __exit__(self, ex_type, ex_value, ex_tb):
+        return self.process()
+
+
 def ip(args, json=None, ns=None, host=None):
     cmd_str = "ip "
     if json:
@@ -47,3 +62,21 @@  import subprocess
     if json:
         return _json.loads(cmd_obj.stdout)
     return cmd_obj
+
+
+def wait_port_listen(port, proto="tcp", ns=None, host=None, sleep=0.005, deadline=1):
+    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)