diff mbox series

[net-next,v4,6/7] selftests: drv-net: add a TCP ping test case (and useful helpers)

Message ID 20240418233844.2762396-7-kuba@kernel.org (mailing list archive)
State Superseded
Delegated to: Netdev Maintainers
Headers show
Series selftests: drv-net: support testing with a remote system | expand

Checks

Context Check Description
netdev/series_format success Posting correctly formatted
netdev/tree_selection success Clearly marked for net-next
netdev/ynl success Generated files up to date; no warnings/errors; no diff in generated;
netdev/fixes_present success Fixes tag not required for -next series
netdev/header_inline success No static functions without inline keyword in header files
netdev/build_32bit success Errors and warnings before: 8 this patch: 8
netdev/build_tools success Errors and warnings before: 0 this patch: 0
netdev/cc_maintainers success CCed 6 of 6 maintainers
netdev/build_clang success Errors and warnings before: 8 this patch: 8
netdev/verify_signedoff success Signed-off-by tag matches author and committer
netdev/deprecated_api success None detected
netdev/check_selftest success No net selftest shell script
netdev/verify_fixes success No Fixes tag
netdev/build_allmodconfig_warn success Errors and warnings before: 8 this patch: 8
netdev/checkpatch success total: 0 errors, 0 warnings, 0 checks, 99 lines checked
netdev/build_clang_rust success No Rust files in patch. Skipping build
netdev/kdoc success Errors and warnings before: 0 this patch: 0
netdev/source_inline success Was 0 now: 0
netdev/contest success net-next-2024-04-19--15-00 (tests: 960)

Commit Message

Jakub Kicinski April 18, 2024, 11:38 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().

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.

Signed-off-by: Jakub Kicinski <kuba@kernel.org>
---
 .../selftests/drivers/net/lib/py/env.py       |  4 +++
 tools/testing/selftests/drivers/net/ping.py   | 24 ++++++++++++-
 tools/testing/selftests/net/lib/py/utils.py   | 35 +++++++++++++++++++
 3 files changed, 62 insertions(+), 1 deletion(-)

Comments

Willem de Bruijn April 19, 2024, 12:55 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().
> 
> 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.
> 
> Signed-off-by: Jakub Kicinski <kuba@kernel.org>
> ---
>  .../selftests/drivers/net/lib/py/env.py       |  4 +++
>  tools/testing/selftests/drivers/net/ping.py   | 24 ++++++++++++-
>  tools/testing/selftests/net/lib/py/utils.py   | 35 +++++++++++++++++++
>  3 files changed, 62 insertions(+), 1 deletion(-)
> 
> 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 9f65a0764aab..15a0bdcb46e2 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
>  
> +import random
> +
>  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
>  
>  
>  def test_v4(cfg) -> None:
> @@ -16,6 +19,25 @@ 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))

Intended to be 1024 + random.randrange(1 << 15)?

> +
> +    with bkg(f"socat -t 2 -u TCP-LISTEN:{port} STDOUT", exit_wait=True) as nc:

Perhaps add reuseaddr to all tests with hand picked ports?

I guess that here the client initiates the close and hits the
TIME_WAIT. But not sure.

The odds of consecutive tests picking the same random ports are low.
But as we add tests and they are run in continuous testing, that
can become an annoying source of flaky runs.

> +        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")
> +
> +    port = random.randrange(1024 + (1 << 15))
> +    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 | socat -t 2 -u STDIN TCP:{cfg.remote_baddr}:{port}", shell=True)
> +    ksft_eq(nc.stdout.strip(), "ping")
> +
> +
diff mbox series

Patch

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 9f65a0764aab..15a0bdcb46e2 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
 
+import random
+
 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
 
 
 def test_v4(cfg) -> None:
@@ -16,6 +19,25 @@  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"socat -t 2 -u TCP-LISTEN:{port} STDOUT", 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")
+
+    port = random.randrange(1024 + (1 << 15))
+    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 | 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, ))
diff --git a/tools/testing/selftests/net/lib/py/utils.py b/tools/testing/selftests/net/lib/py/utils.py
index 7347d0c0ff05..92d9078c164a 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 +41,20 @@  import subprocess
                             (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 +64,21 @@  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=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)