bpf_progs: introduce mainline loaded non-critical gentle.o

with map & program that can be checked from system_server

Test: TreeHugger
Signed-off-by: Maciej Żenczykowski <maze@google.com>
Change-Id: Ife736d54cfc3768aca378d46a092c4518a7302dd

Tethering/apex/Android.bp

@@ -101,6 +101,7 @@ apex {
         "block.o",
         "clatd.o",
         "dscpPolicy.o",
+        "gentle.o",
         "netd.o",
         "offload.o",
         "offload@mainline.o",

bpf_progs/Android.bp

@@ -84,6 +84,16 @@ bpf {
     sub_dir: "net_shared",
 }
 
+bpf {
+    name: "gentle.o",
+    srcs: ["gentle.c"],
+    cflags: [
+        "-Wall",
+        "-Werror",
+    ],
+    sub_dir: "net_shared",
+}
+
 bpf {
     name: "offload.o",
     srcs: ["offload.c"],

bpf_progs/gentle.c

@@ -0,0 +1,30 @@
+/*
+ * Copyright (C) 2024 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#define BPFLOADER_MIN_VER BPFLOADER_MAINLINE_T_VERSION
+
+#include "bpf_helpers.h"
+#include "bpf_net_helpers.h"
+
+DEFINE_BPF_MAP_GRW(test, ARRAY, int, uint64_t, 1, AID_SYSTEM)
+
+DEFINE_BPF_PROG("skfilter/accept", AID_ROOT, AID_SYSTEM, accept)
+(struct __sk_buff *skb) {
+    return 1;
+}
+
+LICENSE("Apache 2.0");
+DISABLE_BTF_ON_USER_BUILDS();

tests/mts/bpf_existence_test.cpp

@@ -91,6 +91,8 @@ static const set<string> MAINLINE_FOR_T_PLUS = {
     SHARED "map_dscpPolicy_ipv4_dscp_policies_map",
     SHARED "map_dscpPolicy_ipv6_dscp_policies_map",
     SHARED "map_dscpPolicy_socket_policy_cache_map",
+    SHARED "map_gentle_test",
+    SHARED "prog_gentle_skfilter_accept",
     NETD "map_netd_app_uid_stats_map",
     NETD "map_netd_configuration_map",
     NETD "map_netd_cookie_tag_map",