selftests/bpf: test device info reporting for bound progs

Check if bound programs report correct device info.  Test
in local namespace, in remote one, back to the local ns,
remove the device and check that information is cleared.

Signed-off-by: Jakub Kicinski <jakub.kicinski@netronome.com>
Reviewed-by: Quentin Monnet <quentin.monnet@netronome.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>

tools/testing/selftests/bpf/test_offload.py

@@ -18,6 +18,8 @@ import argparse
 import json
 import os
 import pprint
+import random
+import string
 import subprocess
 import time
 
@@ -27,6 +29,7 @@ bpf_test_dir = os.path.dirname(os.path.realpath(__file__))
 pp = pprint.PrettyPrinter()
 devs = [] # devices we created for clean up
 files = [] # files to be removed
+netns = [] # net namespaces to be removed
 
 def log_get_sec(level=0):
     return "*" * (log_level + level)
@@ -128,22 +131,25 @@ def rm(f):
     if f in files:
         files.remove(f)
 
-def tool(name, args, flags, JSON=True, fail=True):
+def tool(name, args, flags, JSON=True, ns="", fail=True):
     params = ""
     if JSON:
         params += "%s " % (flags["json"])
 
-    ret, out = cmd(name + " " + params + args, fail=fail)
+    if ns != "":
+        ns = "ip netns exec %s " % (ns)
+
+    ret, out = cmd(ns + name + " " + params + args, fail=fail)
     if JSON and len(out.strip()) != 0:
         return ret, json.loads(out)
     else:
         return ret, out
 
-def bpftool(args, JSON=True, fail=True):
+def bpftool(args, JSON=True, ns="", fail=True):
-    return tool("bpftool", args, {"json":"-p"}, JSON=JSON, fail=fail)
+    return tool("bpftool", args, {"json":"-p"}, JSON=JSON, ns=ns, fail=fail)
 
-def bpftool_prog_list(expected=None):
+def bpftool_prog_list(expected=None, ns=""):
-    _, progs = bpftool("prog show", JSON=True, fail=True)
+    _, progs = bpftool("prog show", JSON=True, ns=ns, fail=True)
     if expected is not None:
         if len(progs) != expected:
             fail(True, "%d BPF programs loaded, expected %d" %
@@ -158,13 +164,13 @@ def bpftool_prog_list_wait(expected=0, n_retry=20):
         time.sleep(0.05)
     raise Exception("Time out waiting for program counts to stabilize want %d, have %d" % (expected, nprogs))
 
-def ip(args, force=False, JSON=True, fail=True):
+def ip(args, force=False, JSON=True, ns="", fail=True):
     if force:
         args = "-force " + args
-    return tool("ip", args, {"json":"-j"}, JSON=JSON, fail=fail)
+    return tool("ip", args, {"json":"-j"}, JSON=JSON, ns=ns, fail=fail)
 
-def tc(args, JSON=True, fail=True):
+def tc(args, JSON=True, ns="", fail=True):
-    return tool("tc", args, {"json":"-p"}, JSON=JSON, fail=fail)
+    return tool("tc", args, {"json":"-p"}, JSON=JSON, ns=ns, fail=fail)
 
 def ethtool(dev, opt, args, fail=True):
     return cmd("ethtool %s %s %s" % (opt, dev["ifname"], args), fail=fail)
@@ -178,6 +184,15 @@ def bpf_pinned(name):
 def bpf_bytecode(bytecode):
     return "bytecode \"%s\"" % (bytecode)
 
+def mknetns(n_retry=10):
+    for i in range(n_retry):
+        name = ''.join([random.choice(string.ascii_letters) for i in range(8)])
+        ret, _ = ip("netns add %s" % (name), fail=False)
+        if ret == 0:
+            netns.append(name)
+            return name
+    return None
+
 class DebugfsDir:
     """
     Class for accessing DebugFS directories as a dictionary.
@@ -237,6 +252,8 @@ class NetdevSim:
         self.dev = self._netdevsim_create()
         devs.append(self)
 
+        self.ns = ""
+
         self.dfs_dir = '/sys/kernel/debug/netdevsim/%s' % (self.dev['ifname'])
         self.dfs_refresh()
 
@@ -257,7 +274,7 @@ class NetdevSim:
 
     def remove(self):
         devs.remove(self)
-        ip("link del dev %s" % (self.dev["ifname"]))
+        ip("link del dev %s" % (self.dev["ifname"]), ns=self.ns)
 
     def dfs_refresh(self):
         self.dfs = DebugfsDir(self.dfs_dir)
@@ -285,6 +302,11 @@ class NetdevSim:
             time.sleep(0.05)
         raise Exception("Time out waiting for program counts to stabilize want %d/%d, have %d bound, %d loaded" % (bound, total, nbound, nprogs))
 
+    def set_ns(self, ns):
+        name = "1" if ns == "" else ns
+        ip("link set dev %s netns %s" % (self.dev["ifname"], name), ns=self.ns)
+        self.ns = ns
+
     def set_mtu(self, mtu, fail=True):
         return ip("link set dev %s mtu %d" % (self.dev["ifname"], mtu),
                   fail=fail)
@@ -372,6 +394,8 @@ def clean_up():
         dev.remove()
     for f in files:
         cmd("rm -f %s" % (f))
+    for ns in netns:
+        cmd("ip netns delete %s" % (ns))
 
 def pin_prog(file_name, idx=0):
     progs = bpftool_prog_list(expected=(idx + 1))
@@ -381,6 +405,35 @@ def pin_prog(file_name, idx=0):
 
     return file_name, bpf_pinned(file_name)
 
+def check_dev_info(other_ns, ns, pin_file=None, removed=False):
+    if removed:
+        bpftool_prog_list(expected=0)
+        ret, err = bpftool("prog show pin %s" % (pin_file), fail=False)
+        fail(ret == 0, "Showing prog with removed device did not fail")
+        fail(err["error"].find("No such device") == -1,
+             "Showing prog with removed device expected ENODEV, error is %s" %
+             (err["error"]))
+        return
+    progs = bpftool_prog_list(expected=int(not removed), ns=ns)
+    prog = progs[0]
+
+    fail("dev" not in prog.keys(), "Device parameters not reported")
+    dev = prog["dev"]
+    fail("ifindex" not in dev.keys(), "Device parameters not reported")
+    fail("ns_dev" not in dev.keys(), "Device parameters not reported")
+    fail("ns_inode" not in dev.keys(), "Device parameters not reported")
+
+    if not removed and not other_ns:
+        fail("ifname" not in dev.keys(), "Ifname not reported")
+        fail(dev["ifname"] != sim["ifname"],
+             "Ifname incorrect %s vs %s" % (dev["ifname"], sim["ifname"]))
+    else:
+        fail("ifname" in dev.keys(), "Ifname is reported for other ns")
+        if removed:
+            fail(dev["ifindex"] != 0, "Device perameters not zero on removed")
+            fail(dev["ns_dev"] != 0, "Device perameters not zero on removed")
+            fail(dev["ns_inode"] != 0, "Device perameters not zero on removed")
+
 # Parse command line
 parser = argparse.ArgumentParser()
 parser.add_argument("--log", help="output verbose log to given file")
@@ -417,6 +470,12 @@ for s in samples:
     skip(ret != 0, "sample %s/%s not found, please compile it" %
          (bpf_test_dir, s))
 
+# Check if net namespaces seem to work
+ns = mknetns()
+skip(ns is None, "Could not create a net namespace")
+cmd("ip netns delete %s" % (ns))
+netns = []
+
 try:
     obj = bpf_obj("sample_ret0.o")
     bytecode = bpf_bytecode("1,6 0 0 4294967295,")
@@ -549,6 +608,8 @@ try:
     progs = bpftool_prog_list(expected=1)
     fail(ipl["xdp"]["prog"]["id"] != progs[0]["id"],
          "Loaded program has wrong ID")
+    fail("dev" in progs[0].keys(),
+         "Device parameters reported for non-offloaded program")
 
     start_test("Test XDP prog replace with bad flags...")
     ret, _ = sim.set_xdp(obj, "offload", force=True, fail=False)
@@ -673,6 +734,35 @@ try:
     fail(time_diff < delay_sec, "Removal process took %s, expected %s" %
          (time_diff, delay_sec))
 
+    # Remove all pinned files and reinstantiate the netdev
+    clean_up()
+    bpftool_prog_list_wait(expected=0)
+
+    sim = NetdevSim()
+    sim.set_ethtool_tc_offloads(True)
+    sim.set_xdp(obj, "offload")
+
+    start_test("Test bpftool bound info reporting (own ns)...")
+    check_dev_info(False, "")
+
+    start_test("Test bpftool bound info reporting (other ns)...")
+    ns = mknetns()
+    sim.set_ns(ns)
+    check_dev_info(True, "")
+
+    start_test("Test bpftool bound info reporting (remote ns)...")
+    check_dev_info(False, ns)
+
+    start_test("Test bpftool bound info reporting (back to own ns)...")
+    sim.set_ns("")
+    check_dev_info(False, "")
+
+    pin_file, _ = pin_prog("/sys/fs/bpf/tmp")
+    sim.remove()
+
+    start_test("Test bpftool bound info reporting (removed dev)...")
+    check_dev_info(True, "", pin_file=pin_file, removed=True)
+
     print("%s: OK" % (os.path.basename(__file__)))
 
 finally: