net-test: add bpf_ktime_get_ns / bpf_ktime_get_boot_ns tests

Tested against various kernels:
  ARCH=um SUBARCH=x86_64 /aosp-tests/net/test/run_net_test.sh --builder bpf_test.py

Test: see above, TreeHugger
Signed-off-by: Maciej Żenczykowski <maze@google.com>
Change-Id: I9ede44099bcf3150bc5fc036843ebabc5cda14b8

2 files changed, 71 insertions, 2 deletions

diff --git a/net/test/bpf.py b/net/test/bpf.py
index 4e4f34f..be4c72f 100755
--- a/net/test/bpf.py
+++ b/net/test/bpf.py
@@ -161,9 +161,11 @@ BPF_FUNC_unspec = 0
 BPF_FUNC_map_lookup_elem = 1
 BPF_FUNC_map_update_elem = 2
 BPF_FUNC_map_delete_elem = 3
+BPF_FUNC_ktime_get_ns = 5
 BPF_FUNC_get_current_uid_gid = 15
 BPF_FUNC_get_socket_cookie = 46
 BPF_FUNC_get_socket_uid = 47
+BPF_FUNC_ktime_get_boot_ns = 125
 # pylint: enable=invalid-name
 
 BPF_F_RDONLY = 1 << 3
@@ -253,10 +255,10 @@ def DeleteMap(map_fd, key):
   BpfSyscall(BPF_MAP_DELETE_ELEM, attr)
 
 
-def BpfProgLoad(prog_type, instructions):
+def BpfProgLoad(prog_type, instructions, prog_license=b"GPL"):
   bpf_prog = "".join(instructions)
   insn_buff = ctypes.create_string_buffer(bpf_prog)
-  gpl_license = ctypes.create_string_buffer(b"GPL")
+  gpl_license = ctypes.create_string_buffer(prog_license)
   log_buf = ctypes.create_string_buffer(b"", LOG_SIZE)
   attr = BpfAttrProgLoad((prog_type, len(insn_buff) / len(BpfInsn),
                           ctypes.addressof(insn_buff),
diff --git a/net/test/bpf_test.py b/net/test/bpf_test.py
index 33ad1da..4a1790d 100755
--- a/net/test/bpf_test.py
+++ b/net/test/bpf_test.py
@@ -78,6 +78,7 @@ from bpf import LookupMap
 from bpf import UpdateMap
 import csocket
 import net_test
+from net_test import LINUX_VERSION
 import sock_diag
 
 libc = ctypes.CDLL(ctypes.util.find_library("c"), use_errno=True)
@@ -85,6 +86,18 @@ libc = ctypes.CDLL(ctypes.util.find_library("c"), use_errno=True)
 HAVE_EBPF_ACCOUNTING = bpf.HAVE_EBPF_4_9
 HAVE_EBPF_SOCKET = bpf.HAVE_EBPF_4_14
 
+# bpf_ktime_get_ns() was made non-GPL requiring in 5.8 and at the same time
+# bpf_ktime_get_boot_ns() was added, both of these changes were backported to
+# Android Common Kernel in 4.14.221, 4.19.175, 5.4.97.
+# As such we require 4.14.222+ 4.19.176+ 5.4.98+ 5.8.0+,
+# but since we only really care about LTS releases:
+HAVE_EBPF_KTIME_GET_NS_APACHE2 = (
+    ((LINUX_VERSION > (4, 14, 221)) and (LINUX_VERSION < (4, 19, 0))) or
+    ((LINUX_VERSION > (4, 19, 175)) and (LINUX_VERSION < (5, 4, 0))) or
+    (LINUX_VERSION > (5, 4, 97))
+)
+HAVE_EBPF_KTIME_GET_BOOT_NS = HAVE_EBPF_KTIME_GET_NS_APACHE2
+
 KEY_SIZE = 8
 VALUE_SIZE = 4
 TOTAL_ENTRIES = 20
@@ -317,6 +330,60 @@ class BpfTest(net_test.NetworkTest):
     SocketUDPLoopBack(packet_count, 6, self.prog_fd)
     self.assertEqual(packet_count * 2, LookupMap(self.map_fd, key).value)
 
+  def testKtimeGetNsGPL(self):
+    instructions = [BpfFuncCall(BPF_FUNC_ktime_get_ns)]
+    instructions += INS_BPF_EXIT_BLOCK
+    self.prog_fd = BpfProgLoad(BPF_PROG_TYPE_SCHED_CLS, instructions)
+    # No exceptions? Good.
+
+  ##############################################################################
+  #
+  # Test for presence of kernel patch:
+  #
+  #   UPSTREAM: net: bpf: Make bpf_ktime_get_ns() available to non GPL programs
+  #
+  # 4.14: https://android-review.googlesource.com/c/kernel/common/+/1585269
+  #       commit cbb4c73f9eab8f3c8ac29175d45c99ccba382e15
+  #
+  # 4.19: https://android-review.googlesource.com/c/kernel/common/+/1355243
+  #       commit 272e21ccc9a92feeee80aff0587410a314b73c5b
+  #
+  # 5.4:  https://android-review.googlesource.com/c/kernel/common/+/1355422
+  #       commit 45217b91eaaa3a563247c4f470f4cb785de6b1c6
+  #
+  @unittest.skipUnless(HAVE_EBPF_KTIME_GET_NS_APACHE2,
+                       "no bpf_ktime_get_ns() support for non-GPL programs")
+  def testKtimeGetNsApache2(self):
+    instructions = [BpfFuncCall(BPF_FUNC_ktime_get_ns)]
+    instructions += INS_BPF_EXIT_BLOCK
+    self.prog_fd = BpfProgLoad(BPF_PROG_TYPE_SCHED_CLS, instructions,
+                               b"Apache 2.0")
+    # No exceptions? Good.
+
+  ##############################################################################
+  #
+  # Test for presence of kernel patch:
+  #
+  #   BACKPORT: bpf: add bpf_ktime_get_boot_ns()
+  #
+  # 4.14: https://android-review.googlesource.com/c/kernel/common/+/1585587
+  #       commit 34073d7a8ee47ca908b56e9a1d14ca0615fdfc09
+  #
+  # 4.19: https://android-review.googlesource.com/c/kernel/common/+/1585606
+  #       commit 4812ec50935dfe59ba9f48a572e278dd0b02af68
+  #
+  # 5.4:  https://android-review.googlesource.com/c/kernel/common/+/1585252
+  #       commit 57b3f4830fb66a6038c4c1c66ca2e138fe8be231
+  #
+  @unittest.skipUnless(HAVE_EBPF_KTIME_GET_BOOT_NS,
+                       "no bpf_ktime_get_boot_ns() support")
+  def testKtimeGetBootNs(self):
+    instructions = [BpfFuncCall(BPF_FUNC_ktime_get_boot_ns)]
+    instructions += INS_BPF_EXIT_BLOCK
+    self.prog_fd = BpfProgLoad(BPF_PROG_TYPE_SCHED_CLS, instructions,
+                               b"Apache 2.0")
+    # No exceptions? Good.
+
   def testGetSocketCookie(self):
     self.map_fd = CreateMap(BPF_MAP_TYPE_HASH, KEY_SIZE, VALUE_SIZE,
                             TOTAL_ENTRIES)