[PATCH bpf-next 6/6] selftests/bpf: Add test for "bpftool feature" command

[Michal Rostecki <mrostecki@opensuse.org>]

Add Python module with tests for "bpftool feature" command which check
whether:

- probing kernel and network devices works
- "section" option selects sections properly
- "filter_in" and "filter_out" options filter results properly
- "macro" option generates C macros properly

Signed-off-by: Michal Rostecki <mrostecki@opensuse.org>
---
 tools/testing/selftests/.gitignore          |   5 +-
 tools/testing/selftests/bpf/Makefile        |   3 +-
 tools/testing/selftests/bpf/test_bpftool.py | 294 ++++++++++++++++++++
 tools/testing/selftests/bpf/test_bpftool.sh |   5 +
 4 files changed, 305 insertions(+), 2 deletions(-)
 create mode 100644 tools/testing/selftests/bpf/test_bpftool.py
 create mode 100755 tools/testing/selftests/bpf/test_bpftool.sh

diff --git a/tools/testing/selftests/.gitignore b/tools/testing/selftests/.gitignore
index 61df01cdf0b2..304fdf1a21dc 100644
--- a/tools/testing/selftests/.gitignore
+++ b/tools/testing/selftests/.gitignore
@@ -3,4 +3,7 @@ gpiogpio-hammer
 gpioinclude/
 gpiolsgpio
 tpm2/SpaceTest.log
-tpm2/*.pyc
+
+# Python bytecode and cache
+__pycache__/
+*.py[cod]
diff --git a/tools/testing/selftests/bpf/Makefile b/tools/testing/selftests/bpf/Makefile
index 257a1aaaa37d..e7d822259c50 100644
--- a/tools/testing/selftests/bpf/Makefile
+++ b/tools/testing/selftests/bpf/Makefile
@@ -62,7 +62,8 @@ TEST_PROGS := test_kmod.sh \
 	test_tc_tunnel.sh \
 	test_tc_edt.sh \
 	test_xdping.sh \
-	test_bpftool_build.sh
+	test_bpftool_build.sh \
+	test_bpftool.sh
 
 TEST_PROGS_EXTENDED := with_addr.sh \
 	with_tunnels.sh \
diff --git a/tools/testing/selftests/bpf/test_bpftool.py b/tools/testing/selftests/bpf/test_bpftool.py
new file mode 100644
index 000000000000..e298dca5fdcf
--- /dev/null
+++ b/tools/testing/selftests/bpf/test_bpftool.py
@@ -0,0 +1,294 @@
+# Copyright (c) 2020 SUSE LLC.
+#
+# This software is licensed under the GNU General License Version 2,
+# June 1991 as shown in the file COPYING in the top-level directory of this
+# source tree.
+#
+# THE COPYRIGHT HOLDERS AND/OR OTHER PARTIES PROVIDE THE PROGRAM "AS IS"
+# WITHOUT WARRANTY OF ANY KIND, EITHER EXPRESSED OR IMPLIED, INCLUDING,
+# BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
+# FOR A PARTICULAR PURPOSE. THE ENTIRE RISK AS TO THE QUALITY AND PERFORMANCE
+# OF THE PROGRAM IS WITH YOU. SHOULD THE PROGRAM PROVE DEFECTIVE, YOU ASSUME
+# THE COST OF ALL NECESSARY SERVICING, REPAIR OR CORRECTION.
+
+import collections
+import functools
+import json
+import os
+import socket
+import subprocess
+import unittest
+
+
+# Add the source tree of bpftool and /usr/local/sbin to PATH
+cur_dir = os.path.dirname(os.path.realpath(__file__))
+bpftool_dir = os.path.abspath(os.path.join(cur_dir, "..", "..", "..", "..",
+                                           "tools", "bpf", "bpftool"))
+os.environ["PATH"] = bpftool_dir + ":/usr/local/sbin:" + os.environ["PATH"]
+
+# Probe sections
+SECTION_SYSTEM_CONFIG_NAME = "system_config"
+SECTION_SYSCALL_CONFIG_NAME = "syscall_config"
+SECTION_PROGRAM_TYPES_NAME = "program_types"
+SECTION_MAP_TYPES_NAME = "map_types"
+SECTION_HELPERS_NAME = "helpers"
+SECTION_MISC_NAME = "misc"
+SECTION_SYSTEM_CONFIG_PATTERN = b"Scanning system configuration..."
+SECTION_SYSCALL_CONFIG_PATTERN = b"Scanning system call availability..."
+SECTION_PROGRAM_TYPES_PATTERN = b"Scanning eBPF program types..."
+SECTION_MAP_TYPES_PATTERN = b"Scanning eBPF map types..."
+SECTION_HELPERS_PATTERN = b"Scanning eBPF helper functions..."
+SECTION_MISC_PATTERN = b"Scanning miscellaneous eBPF features..."
+
+
+class IfaceNotFoundError(Exception):
+    pass
+
+
+class UnprivilegedUserError(Exception):
+    pass
+
+
+def _bpftool(args, json=True):
+    _args = ["bpftool"]
+    if json:
+        _args.append("-j")
+    _args.extend(args)
+
+    res = subprocess.run(_args, capture_output=True)
+    return res.stdout
+
+
+def bpftool(args):
+    return _bpftool(args, json=False)
+
+
+def bpftool_json(args):
+    res = _bpftool(args)
+    return json.loads(res)
+
+
+def get_default_iface():
+    for iface in socket.if_nameindex():
+        if iface[1] != "lo":
+            return iface[1]
+    raise IfaceNotFoundError("Could not find any network interface to probe")
+
+
+def default_iface(f):
+    @functools.wraps(f)
+    def wrapper(*args, **kwargs):
+        iface = get_default_iface()
+        return f(*args, iface, **kwargs)
+    return wrapper
+
+
+class TestBpftool(unittest.TestCase):
+    @classmethod
+    def setUpClass(cls):
+        if os.getuid() != 0:
+            raise UnprivilegedUserError("This test suite eeeds root privileges")
+
+    @default_iface
+    def test_feature_dev(self, iface):
+        expected_lines = [
+            SECTION_SYSCALL_CONFIG_PATTERN,
+            SECTION_PROGRAM_TYPES_PATTERN,
+            SECTION_MAP_TYPES_PATTERN,
+            SECTION_HELPERS_PATTERN,
+            SECTION_MISC_PATTERN,
+        ]
+
+        res = bpftool(["feature", "probe", "dev", iface])
+        for expected_line in expected_lines:
+            self.assertIn(expected_line, res)
+
+    @default_iface
+    def test_feature_dev_json(self, iface):
+        expected_keys = [
+            "syscall_config",
+            "program_types",
+            "map_types",
+            "helpers",
+            "misc",
+        ]
+
+        res = bpftool_json(["feature", "probe", "dev", iface])
+        self.assertCountEqual(res.keys(), expected_keys)
+
+    def test_feature_kernel(self):
+        expected_lines = [
+            SECTION_SYSTEM_CONFIG_PATTERN,
+            SECTION_SYSCALL_CONFIG_PATTERN,
+            SECTION_PROGRAM_TYPES_PATTERN,
+            SECTION_MAP_TYPES_PATTERN,
+            SECTION_HELPERS_PATTERN,
+            SECTION_MISC_PATTERN,
+        ]
+
+        res_default1 = bpftool(["feature"])
+        res_default2 = bpftool(["feature", "probe"])
+        res = bpftool(["feature", "probe", "kernel"])
+
+        for expected_line in expected_lines:
+            self.assertIn(expected_line, res_default1)
+            self.assertIn(expected_line, res_default2)
+            self.assertIn(expected_line, res)
+
+    def test_feature_kernel_json(self):
+        expected_keys = [
+            "system_config",
+            "syscall_config",
+            "program_types",
+            "map_types",
+            "helpers",
+            "misc",
+        ]
+
+        res_default1 = bpftool_json(["feature"])
+        self.assertCountEqual(res_default1.keys(), expected_keys)
+
+        res_default2 = bpftool_json(["feature", "probe"])
+        self.assertCountEqual(res_default2.keys(), expected_keys)
+
+        res = bpftool_json(["feature", "probe", "kernel"])
+        self.assertCountEqual(res.keys(), expected_keys)
+
+    def test_feature_section(self):
+        SectionTestCase = collections.namedtuple(
+            "SectionTestCase",
+            ["section_name", "expected_pattern", "unexpected_patterns"])
+        test_cases = [
+            SectionTestCase(
+                section_name=SECTION_SYSTEM_CONFIG_NAME,
+                expected_pattern=SECTION_SYSTEM_CONFIG_PATTERN,
+                unexpected_patterns=[SECTION_SYSCALL_CONFIG_PATTERN,
+                                     SECTION_PROGRAM_TYPES_PATTERN,
+                                     SECTION_MAP_TYPES_PATTERN,
+                                     SECTION_HELPERS_PATTERN,
+                                     SECTION_MISC_PATTERN]),
+            SectionTestCase(
+                section_name=SECTION_SYSCALL_CONFIG_NAME,
+                expected_pattern=SECTION_SYSCALL_CONFIG_PATTERN,
+                unexpected_patterns=[SECTION_SYSTEM_CONFIG_PATTERN,
+                                     SECTION_PROGRAM_TYPES_PATTERN,
+                                     SECTION_MAP_TYPES_PATTERN,
+                                     SECTION_HELPERS_PATTERN,
+                                     SECTION_MISC_PATTERN]),
+            SectionTestCase(
+                section_name=SECTION_PROGRAM_TYPES_NAME,
+                expected_pattern=SECTION_PROGRAM_TYPES_PATTERN,
+                unexpected_patterns=[SECTION_SYSTEM_CONFIG_PATTERN,
+                                     SECTION_SYSCALL_CONFIG_PATTERN,
+                                     SECTION_MAP_TYPES_PATTERN,
+                                     SECTION_HELPERS_PATTERN,
+                                     SECTION_MISC_PATTERN]),
+            SectionTestCase(
+                section_name=SECTION_MAP_TYPES_NAME,
+                expected_pattern=SECTION_MAP_TYPES_PATTERN,
+                unexpected_patterns=[SECTION_SYSTEM_CONFIG_PATTERN,
+                                     SECTION_SYSCALL_CONFIG_PATTERN,
+                                     SECTION_PROGRAM_TYPES_PATTERN,
+                                     SECTION_HELPERS_PATTERN,
+                                     SECTION_MISC_PATTERN]),
+            SectionTestCase(
+                section_name=SECTION_HELPERS_NAME,
+                expected_pattern=SECTION_HELPERS_PATTERN,
+                unexpected_patterns=[SECTION_SYSTEM_CONFIG_PATTERN,
+                                     SECTION_SYSCALL_CONFIG_PATTERN,
+                                     SECTION_PROGRAM_TYPES_PATTERN,
+                                     SECTION_MAP_TYPES_PATTERN,
+                                     SECTION_MISC_PATTERN]),
+            SectionTestCase(
+                section_name=SECTION_MISC_NAME,
+                expected_pattern=SECTION_MISC_PATTERN,
+                unexpected_patterns=[SECTION_SYSTEM_CONFIG_PATTERN,
+                                     SECTION_SYSCALL_CONFIG_PATTERN,
+                                     SECTION_PROGRAM_TYPES_PATTERN,
+                                     SECTION_MAP_TYPES_PATTERN,
+                                     SECTION_HELPERS_PATTERN]),
+        ]
+
+        for tc in test_cases:
+            res = bpftool(["feature", "probe", "kernel",
+                           "section", tc.section_name])
+            self.assertIn(tc.expected_pattern, res)
+            for pattern in tc.unexpected_patterns:
+                self.assertNotIn(pattern, res)
+
+    def test_feature_section_json(self):
+        res_syscall_config = bpftool_json(["feature", "probe", "kernel",
+                                           "section", "syscall_config"])
+        self.assertCountEqual(res_syscall_config.keys(), ["syscall_config"])
+
+        res_system_config = bpftool_json(["feature", "probe", "kernel",
+                                          "section", "system_config"])
+        self.assertCountEqual(res_system_config.keys(), ["system_config"])
+
+        res_program_types = bpftool_json(["feature", "probe", "kernel",
+                                          "section", "program_types"])
+        self.assertCountEqual(res_program_types.keys(), ["program_types"])
+
+        res_map_types = bpftool_json(["feature", "probe", "kernel",
+                                      "section", "map_types"])
+        self.assertCountEqual(res_map_types.keys(), ["map_types"])
+
+        res_helpers = bpftool_json(["feature", "probe", "kernel",
+                                    "section", "helpers"])
+        self.assertCountEqual(res_helpers.keys(), ["helpers"])
+
+        res_misc = bpftool_json(["feature", "probe", "kernel",
+                                 "section", "misc"])
+        self.assertCountEqual(res_misc.keys(), ["misc"])
+
+    def _assert_pattern_in_dict(self, dct, pattern, check_keys=False):
+        """Check if all string values inside dictionary contain the given
+        pattern.
+        """
+        for key, value in dct.items():
+            if check_keys:
+                self.assertIn(pattern, key)
+            if isinstance(value, dict):
+                self._assert_pattern_in_dict(value, pattern, check_keys=True)
+            elif isinstance(value, str):
+                self.assertIn(pattern, value)
+
+    def _assert_pattern_not_in_dict(self, dct, pattern, check_keys=False):
+        """Check if all string values inside dictionary do not containe the
+        given pattern.
+        """
+        for key, value in dct.items():
+            if check_keys:
+                self.assertNotIn(pattern, key)
+            if isinstance(value, dict):
+                self._assert_pattern_not_in_dict(value, pattern,
+                                                 check_keys=True)
+            elif isinstance(value, str):
+                self.assertNotIn(pattern, value)
+
+    def test_feature_filter_in_json(self):
+        res = bpftool_json(["feature", "probe", "kernel",
+                            "filter_in", "trace"])
+        self._assert_pattern_in_dict(res, "trace")
+
+    def test_feature_filter_out_json(self):
+        res = bpftool_json(["feature", "probe", "kernel",
+                            "filter_out", "trace"])
+        self._assert_pattern_not_in_dict(res, "trace")
+
+    def test_feature_macros(self):
+        expected_patterns = [
+            b"/\*\*\* System call availability \*\*\*/",
+            b"#define HAVE_BPF_SYSCALL",
+            b"/\*\*\* eBPF program types \*\*\*/",
+            b"#define HAVE.*PROG_TYPE",
+            b"/\*\*\* eBPF map types \*\*\*/",
+            b"#define HAVE.*MAP_TYPE",
+            b"/\*\*\* eBPF helper functions \*\*\*/",
+            b"#define HAVE.*HELPER",
+            b"/\*\*\* eBPF misc features \*\*\*/",
+        ]
+
+        res = bpftool(["feature", "probe", "macros"])
+        for pattern in expected_patterns:
+            self.assertRegex(res, pattern)
diff --git a/tools/testing/selftests/bpf/test_bpftool.sh b/tools/testing/selftests/bpf/test_bpftool.sh
new file mode 100755
index 000000000000..66690778e36d
--- /dev/null
+++ b/tools/testing/selftests/bpf/test_bpftool.sh
@@ -0,0 +1,5 @@
+#!/bin/bash
+# SPDX-License-Identifier: GPL-2.0
+# Copyright (c) 2020 SUSE LLC.
+
+python3 -m unittest -v test_bpftool.TestBpftool
-- 
2.25.0