Initial checkin for bpf project
Copied the files from system/netd into system/bpf. No modification is
made to the files.
Test: this doesn't build since the Android.bp file is missing
Bug: 112334572
Change-Id: Ia090a429dd416e07c46766784fb3dd2037201525
diff --git a/bpfloader/Android.bp b/bpfloader/Android.bp
new file mode 100644
index 0000000..fe52bcf
--- /dev/null
+++ b/bpfloader/Android.bp
@@ -0,0 +1,58 @@
+//
+// Copyright (C) 2018 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.
+//
+
+//
+// bpfLoad binary
+//
+cc_binary {
+ name: "bpfloader",
+
+ defaults: ["netd_defaults"],
+ cflags: [
+ "-Wall",
+ "-Werror",
+ "-Wthread-safety",
+ ],
+ sanitize: {
+ integer_overflow: true,
+ },
+ clang: true,
+ shared_libs: [
+ "libcutils",
+ "libbpf",
+ "libbase",
+ "liblog",
+ "libnetdutils",
+ ],
+ srcs: [
+ "BpfLoader.cpp",
+ ],
+
+ required: [
+ "bpf_kern.o",
+ ],
+
+}
+
+bpf {
+ name: "bpf_kern.o",
+ srcs: ["bpf_kern.c"],
+ cflags: [
+ "-Wall",
+ "-Werror",
+ ],
+ include_dirs: ["system/netd/libbpf/include"],
+}
diff --git a/bpfloader/BpfLoader.cpp b/bpfloader/BpfLoader.cpp
new file mode 100644
index 0000000..c7b1332
--- /dev/null
+++ b/bpfloader/BpfLoader.cpp
@@ -0,0 +1,101 @@
+/*
+ * Copyright (C) 2017 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.
+ */
+
+#ifndef LOG_TAG
+#define LOG_TAG "bpfloader"
+#endif
+
+#include <arpa/inet.h>
+#include <elf.h>
+#include <error.h>
+#include <fcntl.h>
+#include <inttypes.h>
+#include <linux/bpf.h>
+#include <linux/unistd.h>
+#include <net/if.h>
+#include <stdint.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <unistd.h>
+
+#include <sys/mman.h>
+#include <sys/socket.h>
+#include <sys/stat.h>
+#include <sys/types.h>
+
+#include <android-base/stringprintf.h>
+#include <android-base/unique_fd.h>
+#include <log/log.h>
+
+#include <netdutils/Misc.h>
+#include <netdutils/Slice.h>
+#include "bpf/BpfUtils.h"
+#include "bpf/bpf_shared.h"
+
+using android::base::unique_fd;
+using android::netdutils::Slice;
+
+#define BPF_PROG_PATH "/system/etc/bpf"
+#define BPF_PROG_SRC BPF_PROG_PATH "/bpf_kern.o"
+
+#define CLEANANDEXIT(ret, mapPatterns) \
+ do { \
+ for (int i = 0; i < mapPatterns.size(); i++) { \
+ if (mapPatterns[i].fd > -1) { \
+ close(mapPatterns[i].fd); \
+ } \
+ } \
+ return ret; \
+ } while (0)
+
+using android::bpf::BpfMapInfo;
+using android::bpf::BpfProgInfo;
+
+int main() {
+ const std::vector<BpfMapInfo> mapPatterns = {
+ BpfMapInfo(COOKIE_TAG_MAP, COOKIE_TAG_MAP_PATH),
+ BpfMapInfo(UID_COUNTERSET_MAP, UID_COUNTERSET_MAP_PATH),
+ BpfMapInfo(APP_UID_STATS_MAP, APP_UID_STATS_MAP_PATH),
+ BpfMapInfo(UID_STATS_MAP, UID_STATS_MAP_PATH),
+ BpfMapInfo(TAG_STATS_MAP, TAG_STATS_MAP_PATH),
+ BpfMapInfo(IFACE_STATS_MAP, IFACE_STATS_MAP_PATH),
+ BpfMapInfo(CONFIGURATION_MAP, CONFIGURATION_MAP_PATH),
+ BpfMapInfo(UID_OWNER_MAP, UID_OWNER_MAP_PATH),
+ };
+ for (int i = 0; i < mapPatterns.size(); i++) {
+ if (mapPatterns[i].fd < 0) {
+ ALOGE("Rerieve Map from %s failed: %d", mapPatterns[i].path.c_str(), mapPatterns[i].fd);
+ CLEANANDEXIT(-1, mapPatterns);
+ }
+ }
+ BpfProgInfo programs[] = {
+ {BPF_CGROUP_INET_EGRESS, BPF_EGRESS_PROG_PATH, BPF_CGROUP_EGRESS_PROG_NAME,
+ BPF_PROG_TYPE_CGROUP_SKB, unique_fd(-1)},
+ {BPF_CGROUP_INET_INGRESS, BPF_INGRESS_PROG_PATH, BPF_CGROUP_INGRESS_PROG_NAME,
+ BPF_PROG_TYPE_CGROUP_SKB, unique_fd(-1)},
+ {MAX_BPF_ATTACH_TYPE, XT_BPF_INGRESS_PROG_PATH, XT_BPF_INGRESS_PROG_NAME,
+ BPF_PROG_TYPE_SOCKET_FILTER, unique_fd(-1)},
+ {MAX_BPF_ATTACH_TYPE, XT_BPF_EGRESS_PROG_PATH, XT_BPF_EGRESS_PROG_NAME,
+ BPF_PROG_TYPE_SOCKET_FILTER, unique_fd(-1)},
+ {MAX_BPF_ATTACH_TYPE, XT_BPF_WHITELIST_PROG_PATH, XT_BPF_WHITELIST_PROG_NAME,
+ BPF_PROG_TYPE_SOCKET_FILTER, unique_fd(-1)},
+ {MAX_BPF_ATTACH_TYPE, XT_BPF_BLACKLIST_PROG_PATH, XT_BPF_BLACKLIST_PROG_NAME,
+ BPF_PROG_TYPE_SOCKET_FILTER, unique_fd(-1)}};
+ int ret = android::bpf::parseProgramsFromFile(BPF_PROG_SRC, programs, ARRAY_SIZE(programs),
+ mapPatterns);
+ CLEANANDEXIT(ret, mapPatterns);
+}
diff --git a/bpfloader/bpf_kern.c b/bpfloader/bpf_kern.c
new file mode 100644
index 0000000..4fe8140
--- /dev/null
+++ b/bpfloader/bpf_kern.c
@@ -0,0 +1,60 @@
+/*
+ * Copyright (C) 2018 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.
+ */
+
+#include <linux/bpf.h>
+#include "bpf_kern.h"
+
+
+ELF_SEC(BPF_CGROUP_INGRESS_PROG_NAME)
+int bpf_cgroup_ingress(struct __sk_buff* skb) {
+ return bpf_traffic_account(skb, BPF_INGRESS);
+}
+
+ELF_SEC(BPF_CGROUP_EGRESS_PROG_NAME)
+int bpf_cgroup_egress(struct __sk_buff* skb) {
+ return bpf_traffic_account(skb, BPF_EGRESS);
+}
+
+ELF_SEC(XT_BPF_EGRESS_PROG_NAME)
+int xt_bpf_egress_prog(struct __sk_buff* skb) {
+ uint32_t key = skb->ifindex;
+ bpf_update_stats(skb, IFACE_STATS_MAP, BPF_EGRESS, &key);
+ return BPF_MATCH;
+}
+
+ELF_SEC(XT_BPF_INGRESS_PROG_NAME)
+int xt_bpf_ingress_prog(struct __sk_buff* skb) {
+ uint32_t key = skb->ifindex;
+ bpf_update_stats(skb, IFACE_STATS_MAP, BPF_INGRESS, &key);
+ return BPF_MATCH;
+}
+
+ELF_SEC(XT_BPF_WHITELIST_PROG_NAME)
+int xt_bpf_whitelist_prog(struct __sk_buff* skb) {
+ uint32_t sock_uid = get_socket_uid(skb);
+ if (is_system_uid(sock_uid)) return BPF_MATCH;
+ uint8_t* whitelistMatch = find_map_entry(UID_OWNER_MAP, &sock_uid);
+ if (whitelistMatch) return *whitelistMatch & HAPPY_BOX_MATCH;
+ return BPF_NOMATCH;
+}
+
+ELF_SEC(XT_BPF_BLACKLIST_PROG_NAME)
+int xt_bpf_blacklist_prog(struct __sk_buff* skb) {
+ uint32_t sock_uid = get_socket_uid(skb);
+ uint8_t* blacklistMatch = find_map_entry(UID_OWNER_MAP, &sock_uid);
+ if (blacklistMatch) return *blacklistMatch & PENALTY_BOX_MATCH;
+ return BPF_NOMATCH;
+}
diff --git a/bpfloader/bpf_kern.h b/bpfloader/bpf_kern.h
new file mode 100644
index 0000000..e56033d
--- /dev/null
+++ b/bpfloader/bpf_kern.h
@@ -0,0 +1,220 @@
+/*
+ * Copyright (C) 2018 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.
+ */
+
+/*
+ * This h file together with bpf_kern.c is used for compiling the eBPF kernel
+ * program. To generate the bpf_kern.o file manually, use the clang prebuilt in
+ * this android tree to compile the files with --target=bpf options. For
+ * example, in system/netd/ directory, execute the following command:
+ * $: ANDROID_BASE_DIRECTORY/prebuilts/clang/host/linux-x86/clang-4691093/bin/clang \
+ * -I ANDROID_BASE_DIRECTORY/bionic/libc/kernel/uapi/ \
+ * -I ANDROID_BASE_DIRECTORY/system/netd/bpfloader/ \
+ * -I ANDROID_BASE_DIRECTORY/bionic/libc/kernel/android/uapi/ \
+ * -I ANDROID_BASE_DIRECTORY/bionic/libc/include \
+ * -I ANDROID_BASE_DIRECTORY/system/netd/libbpf/include \
+ * --target=bpf -O2 -c bpfloader/bpf_kern.c -o bpfloader/bpf_kern.o
+ */
+
+#include <linux/bpf.h>
+#include <linux/if.h>
+#include <linux/if_ether.h>
+#include <linux/in.h>
+#include <linux/in6.h>
+#include <linux/ip.h>
+#include <linux/ipv6.h>
+#include <stdbool.h>
+#include <stdint.h>
+#include "bpf/bpf_shared.h"
+
+#define ELF_SEC(NAME) __attribute__((section(NAME), used))
+
+struct uid_tag {
+ uint32_t uid;
+ uint32_t tag;
+};
+
+struct stats_key {
+ uint32_t uid;
+ uint32_t tag;
+ uint32_t counterSet;
+ uint32_t ifaceIndex;
+};
+
+struct stats_value {
+ uint64_t rxPackets;
+ uint64_t rxBytes;
+ uint64_t txPackets;
+ uint64_t txBytes;
+};
+
+/* helper functions called from eBPF programs written in C */
+static void* (*find_map_entry)(uint64_t map, void* key) = (void*)BPF_FUNC_map_lookup_elem;
+static int (*write_to_map_entry)(uint64_t map, void* key, void* value,
+ uint64_t flags) = (void*)BPF_FUNC_map_update_elem;
+static int (*delete_map_entry)(uint64_t map, void* key) = (void*)BPF_FUNC_map_delete_elem;
+static uint64_t (*get_socket_cookie)(struct __sk_buff* skb) = (void*)BPF_FUNC_get_socket_cookie;
+static uint32_t (*get_socket_uid)(struct __sk_buff* skb) = (void*)BPF_FUNC_get_socket_uid;
+static int (*bpf_skb_load_bytes)(struct __sk_buff* skb, int off, void* to,
+ int len) = (void*)BPF_FUNC_skb_load_bytes;
+
+// This is defined for cgroup bpf filter only.
+#define BPF_PASS 1
+#define BPF_DROP 0
+
+// This is used for xt_bpf program only.
+#define BPF_NOMATCH 0
+#define BPF_MATCH 1
+
+#define BPF_EGRESS 0
+#define BPF_INGRESS 1
+
+#define IP_PROTO_OFF offsetof(struct iphdr, protocol)
+#define IPV6_PROTO_OFF offsetof(struct ipv6hdr, nexthdr)
+#define IPPROTO_IHL_OFF 0
+#define TCP_FLAG_OFF 13
+#define RST_OFFSET 2
+
+static __always_inline int is_system_uid(uint32_t uid) {
+ return (uid <= MAX_SYSTEM_UID) && (uid >= MIN_SYSTEM_UID);
+}
+
+static __always_inline inline void bpf_update_stats(struct __sk_buff* skb, uint64_t map,
+ int direction, void *key) {
+ struct stats_value* value;
+ value = find_map_entry(map, key);
+ if (!value) {
+ struct stats_value newValue = {};
+ write_to_map_entry(map, key, &newValue, BPF_NOEXIST);
+ value = find_map_entry(map, key);
+ }
+ if (value) {
+ if (direction == BPF_EGRESS) {
+ __sync_fetch_and_add(&value->txPackets, 1);
+ __sync_fetch_and_add(&value->txBytes, skb->len);
+ } else if (direction == BPF_INGRESS) {
+ __sync_fetch_and_add(&value->rxPackets, 1);
+ __sync_fetch_and_add(&value->rxBytes, skb->len);
+ }
+ }
+}
+
+static inline bool skip_owner_match(struct __sk_buff* skb) {
+ int offset = -1;
+ int ret = 0;
+ if (skb->protocol == ETH_P_IP) {
+ offset = IP_PROTO_OFF;
+ uint8_t proto, ihl;
+ uint16_t flag;
+ ret = bpf_skb_load_bytes(skb, offset, &proto, 1);
+ if (!ret) {
+ if (proto == IPPROTO_ESP) {
+ return true;
+ } else if (proto == IPPROTO_TCP) {
+ ret = bpf_skb_load_bytes(skb, IPPROTO_IHL_OFF, &ihl, 1);
+ ihl = ihl & 0x0F;
+ ret = bpf_skb_load_bytes(skb, ihl * 4 + TCP_FLAG_OFF, &flag, 1);
+ if (ret == 0 && (flag >> RST_OFFSET & 1)) {
+ return true;
+ }
+ }
+ }
+ } else if (skb->protocol == ETH_P_IPV6) {
+ offset = IPV6_PROTO_OFF;
+ uint8_t proto;
+ ret = bpf_skb_load_bytes(skb, offset, &proto, 1);
+ if (!ret) {
+ if (proto == IPPROTO_ESP) {
+ return true;
+ } else if (proto == IPPROTO_TCP) {
+ uint16_t flag;
+ ret = bpf_skb_load_bytes(skb, sizeof(struct ipv6hdr) + TCP_FLAG_OFF, &flag, 1);
+ if (ret == 0 && (flag >> RST_OFFSET & 1)) {
+ return true;
+ }
+ }
+ }
+ }
+ return false;
+}
+
+static __always_inline BpfConfig getConfig() {
+ uint32_t mapSettingKey = CONFIGURATION_KEY;
+ BpfConfig* config = find_map_entry(CONFIGURATION_MAP, &mapSettingKey);
+ if (!config) {
+ // Couldn't read configuration entry. Assume everything is disabled.
+ return DEFAULT_CONFIG;
+ }
+ return *config;
+}
+
+static inline int bpf_owner_match(struct __sk_buff* skb, uint32_t uid) {
+ if (skip_owner_match(skb)) return BPF_PASS;
+
+ if ((uid <= MAX_SYSTEM_UID) && (uid >= MIN_SYSTEM_UID)) return BPF_PASS;
+
+ BpfConfig enabledRules = getConfig();
+ if (!enabledRules) {
+ return BPF_PASS;
+ }
+
+ uint8_t* uidEntry = find_map_entry(UID_OWNER_MAP, &uid);
+ uint8_t uidRules = uidEntry ? *uidEntry : 0;
+ if ((enabledRules & DOZABLE_MATCH) && !(uidRules & DOZABLE_MATCH)) {
+ return BPF_DROP;
+ }
+ if ((enabledRules & STANDBY_MATCH) && (uidRules & STANDBY_MATCH)) {
+ return BPF_DROP;
+ }
+ if ((enabledRules & POWERSAVE_MATCH) && !(uidRules & POWERSAVE_MATCH)) {
+ return BPF_DROP;
+ }
+ return BPF_PASS;
+}
+
+static __always_inline inline int bpf_traffic_account(struct __sk_buff* skb, int direction) {
+ uint32_t sock_uid = get_socket_uid(skb);
+ int match = bpf_owner_match(skb, sock_uid);
+ if ((direction == BPF_EGRESS) && (match == BPF_DROP)) {
+ // If an outbound packet is going to be dropped, we do not count that
+ // traffic.
+ return match;
+ }
+
+ uint64_t cookie = get_socket_cookie(skb);
+ struct uid_tag* utag = find_map_entry(COOKIE_TAG_MAP, &cookie);
+ uint32_t uid, tag;
+ if (utag) {
+ uid = utag->uid;
+ tag = utag->tag;
+ } else {
+ uid = sock_uid;
+ tag = 0;
+ }
+
+ struct stats_key key = {.uid = uid, .tag = tag, .counterSet = 0, .ifaceIndex = skb->ifindex};
+
+ uint8_t* counterSet = find_map_entry(UID_COUNTERSET_MAP, &uid);
+ if (counterSet) key.counterSet = (uint32_t)*counterSet;
+
+ if (tag) {
+ bpf_update_stats(skb, TAG_STATS_MAP, direction, &key);
+ }
+
+ key.tag = 0;
+ bpf_update_stats(skb, UID_STATS_MAP, direction, &key);
+ bpf_update_stats(skb, APP_UID_STATS_MAP, direction, &uid);
+ return match;
+}
diff --git a/libbpf/BpfMapTest.cpp b/libbpf/BpfMapTest.cpp
new file mode 100644
index 0000000..e367bdb
--- /dev/null
+++ b/libbpf/BpfMapTest.cpp
@@ -0,0 +1,276 @@
+/*
+ * Copyright (C) 2018 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.
+ */
+
+#include <fstream>
+#include <iostream>
+#include <string>
+#include <vector>
+
+#include <fcntl.h>
+#include <inttypes.h>
+#include <linux/inet_diag.h>
+#include <linux/sock_diag.h>
+#include <net/if.h>
+#include <sys/socket.h>
+#include <sys/types.h>
+#include <unistd.h>
+
+#include <gtest/gtest.h>
+
+#include <android-base/stringprintf.h>
+#include <android-base/strings.h>
+
+#include <netdutils/MockSyscalls.h>
+#include "bpf/BpfMap.h"
+#include "bpf/BpfNetworkStats.h"
+#include "bpf/BpfUtils.h"
+
+using ::testing::_;
+using ::testing::ByMove;
+using ::testing::Invoke;
+using ::testing::Return;
+using ::testing::StrictMock;
+using ::testing::Test;
+
+namespace android {
+namespace bpf {
+
+using base::unique_fd;
+using netdutils::StatusOr;
+
+constexpr uint32_t TEST_MAP_SIZE = 10;
+constexpr uint32_t TEST_KEY1 = 1;
+constexpr uint32_t TEST_VALUE1 = 10;
+constexpr const char PINNED_MAP_PATH[] = "/sys/fs/bpf/testMap";
+
+class BpfMapTest : public testing::Test {
+ protected:
+ BpfMapTest() {}
+ int mMapFd;
+
+ void SetUp() {
+ if (!access(PINNED_MAP_PATH, R_OK)) {
+ EXPECT_EQ(0, remove(PINNED_MAP_PATH));
+ }
+ mMapFd = createMap(BPF_MAP_TYPE_HASH, sizeof(uint32_t), sizeof(uint32_t), TEST_MAP_SIZE,
+ BPF_F_NO_PREALLOC);
+ }
+
+ void TearDown() {
+ if (!access(PINNED_MAP_PATH, R_OK)) {
+ EXPECT_EQ(0, remove(PINNED_MAP_PATH));
+ }
+ close(mMapFd);
+ }
+
+ void checkMapInvalid(BpfMap<uint32_t, uint32_t>& map) {
+ EXPECT_FALSE(map.isValid());
+ EXPECT_EQ(-1, map.getMap().get());
+ EXPECT_TRUE(map.getPinnedPath().empty());
+ }
+
+ void checkMapValid(BpfMap<uint32_t, uint32_t>& map) {
+ EXPECT_LE(0, map.getMap().get());
+ EXPECT_TRUE(map.isValid());
+ }
+
+ void writeToMapAndCheck(BpfMap<uint32_t, uint32_t>& map, uint32_t key, uint32_t value) {
+ ASSERT_TRUE(isOk(map.writeValue(key, value, BPF_ANY)));
+ uint32_t value_read;
+ ASSERT_EQ(0, findMapEntry(map.getMap(), &key, &value_read));
+ checkValueAndStatus(value, value_read);
+ }
+
+ void checkValueAndStatus(uint32_t refValue, StatusOr<uint32_t> value) {
+ ASSERT_TRUE(isOk(value.status()));
+ ASSERT_EQ(refValue, value.value());
+ }
+
+ void populateMap(uint32_t total, BpfMap<uint32_t, uint32_t>& map) {
+ for (uint32_t key = 0; key < total; key++) {
+ uint32_t value = key * 10;
+ EXPECT_TRUE(isOk(map.writeValue(key, value, BPF_ANY)));
+ }
+ }
+
+ void expectMapEmpty(BpfMap<uint32_t, uint32_t>& map) {
+ auto isEmpty = map.isEmpty();
+ ASSERT_TRUE(isOk(isEmpty));
+ ASSERT_TRUE(isEmpty.value());
+ }
+};
+
+TEST_F(BpfMapTest, constructor) {
+ BpfMap<uint32_t, uint32_t> testMap1;
+ checkMapInvalid(testMap1);
+
+ BpfMap<uint32_t, uint32_t> testMap2(mMapFd);
+ checkMapValid(testMap2);
+ EXPECT_TRUE(testMap2.getPinnedPath().empty());
+
+ BpfMap<uint32_t, uint32_t> testMap3(BPF_MAP_TYPE_HASH, TEST_MAP_SIZE, BPF_F_NO_PREALLOC);
+ checkMapValid(testMap3);
+ EXPECT_TRUE(testMap3.getPinnedPath().empty());
+}
+
+TEST_F(BpfMapTest, basicHelpers) {
+ BpfMap<uint32_t, uint32_t> testMap(mMapFd);
+ uint32_t key = TEST_KEY1;
+ uint32_t value_write = TEST_VALUE1;
+ writeToMapAndCheck(testMap, key, value_write);
+ StatusOr<uint32_t> value_read = testMap.readValue(key);
+ checkValueAndStatus(value_write, value_read);
+ StatusOr<uint32_t> key_read = testMap.getFirstKey();
+ checkValueAndStatus(key, key_read);
+ ASSERT_TRUE(isOk(testMap.deleteValue(key)));
+ ASSERT_GT(0, findMapEntry(testMap.getMap(), &key, &value_read));
+ ASSERT_EQ(ENOENT, errno);
+}
+
+TEST_F(BpfMapTest, reset) {
+ BpfMap<uint32_t, uint32_t> testMap;
+ testMap.reset(mMapFd);
+ uint32_t key = TEST_KEY1;
+ uint32_t value_write = TEST_VALUE1;
+ writeToMapAndCheck(testMap, key, value_write);
+ testMap.reset();
+ checkMapInvalid(testMap);
+ unique_fd invalidFd(mMapFd);
+ ASSERT_GT(0, findMapEntry(invalidFd, &key, &value_write));
+ ASSERT_EQ(EBADF, errno);
+}
+
+TEST_F(BpfMapTest, moveConstructor) {
+ BpfMap<uint32_t, uint32_t> testMap1(mMapFd);
+ BpfMap<uint32_t, uint32_t> testMap2;
+ testMap2 = std::move(testMap1);
+ uint32_t key = TEST_KEY1;
+ checkMapInvalid(testMap1);
+ uint32_t value = TEST_VALUE1;
+ writeToMapAndCheck(testMap2, key, value);
+}
+
+TEST_F(BpfMapTest, pinnedToPath) {
+ BpfMap<uint32_t, uint32_t> testMap1(mMapFd);
+ EXPECT_OK(testMap1.pinToPath(PINNED_MAP_PATH));
+ EXPECT_EQ(0, access(PINNED_MAP_PATH, R_OK));
+ EXPECT_EQ(0, testMap1.getPinnedPath().compare(PINNED_MAP_PATH));
+ BpfMap<uint32_t, uint32_t> testMap2(mapRetrieve(PINNED_MAP_PATH, 0));
+ checkMapValid(testMap2);
+ uint32_t key = TEST_KEY1;
+ uint32_t value = TEST_VALUE1;
+ writeToMapAndCheck(testMap1, key, value);
+ StatusOr<uint32_t> value_read = testMap2.readValue(key);
+ checkValueAndStatus(value, value_read);
+}
+
+TEST_F(BpfMapTest, SetUpMap) {
+ BpfMap<uint32_t, uint32_t> testMap1;
+ EXPECT_OK(testMap1.getOrCreate(TEST_MAP_SIZE, PINNED_MAP_PATH, BPF_MAP_TYPE_HASH));
+ EXPECT_EQ(0, access(PINNED_MAP_PATH, R_OK));
+ checkMapValid(testMap1);
+ EXPECT_EQ(0, testMap1.getPinnedPath().compare(PINNED_MAP_PATH));
+ BpfMap<uint32_t, uint32_t> testMap2;
+ EXPECT_OK(testMap2.getOrCreate(TEST_MAP_SIZE, PINNED_MAP_PATH, BPF_MAP_TYPE_HASH));
+ checkMapValid(testMap2);
+ EXPECT_EQ(0, testMap2.getPinnedPath().compare(PINNED_MAP_PATH));
+ uint32_t key = TEST_KEY1;
+ uint32_t value = TEST_VALUE1;
+ writeToMapAndCheck(testMap1, key, value);
+ StatusOr<uint32_t> value_read = testMap2.readValue(key);
+ checkValueAndStatus(value, value_read);
+}
+
+TEST_F(BpfMapTest, iterate) {
+ BpfMap<uint32_t, uint32_t> testMap(mMapFd);
+ populateMap(TEST_MAP_SIZE, testMap);
+ int totalCount = 0;
+ int totalSum = 0;
+ const auto iterateWithDeletion = [&totalCount, &totalSum](const uint32_t& key,
+ BpfMap<uint32_t, uint32_t>& map) {
+ EXPECT_GE((uint32_t)TEST_MAP_SIZE, key);
+ totalCount++;
+ totalSum += key;
+ return map.deleteValue(key);
+ };
+ EXPECT_OK(testMap.iterate(iterateWithDeletion));
+ EXPECT_EQ((int)TEST_MAP_SIZE, totalCount);
+ EXPECT_EQ(((1 + TEST_MAP_SIZE - 1) * (TEST_MAP_SIZE - 1)) / 2, (uint32_t)totalSum);
+ expectMapEmpty(testMap);
+}
+
+TEST_F(BpfMapTest, iterateWithValue) {
+ BpfMap<uint32_t, uint32_t> testMap(mMapFd);
+ populateMap(TEST_MAP_SIZE, testMap);
+ int totalCount = 0;
+ int totalSum = 0;
+ const auto iterateWithDeletion = [&totalCount, &totalSum](const uint32_t& key,
+ const uint32_t& value,
+ BpfMap<uint32_t, uint32_t>& map) {
+ EXPECT_GE((uint32_t)TEST_MAP_SIZE, key);
+ EXPECT_EQ(value, key * 10);
+ totalCount++;
+ totalSum += value;
+ return map.deleteValue(key);
+ };
+ EXPECT_OK(testMap.iterateWithValue(iterateWithDeletion));
+ EXPECT_EQ((int)TEST_MAP_SIZE, totalCount);
+ EXPECT_EQ(((1 + TEST_MAP_SIZE - 1) * (TEST_MAP_SIZE - 1)) * 5, (uint32_t)totalSum);
+ expectMapEmpty(testMap);
+}
+
+TEST_F(BpfMapTest, mapIsEmpty) {
+ BpfMap<uint32_t, uint32_t> testMap(mMapFd);
+ expectMapEmpty(testMap);
+ uint32_t key = TEST_KEY1;
+ uint32_t value_write = TEST_VALUE1;
+ writeToMapAndCheck(testMap, key, value_write);
+ auto isEmpty = testMap.isEmpty();
+ ASSERT_TRUE(isOk(isEmpty));
+ ASSERT_FALSE(isEmpty.value());
+ ASSERT_TRUE(isOk(testMap.deleteValue(key)));
+ ASSERT_GT(0, findMapEntry(testMap.getMap(), &key, &value_write));
+ ASSERT_EQ(ENOENT, errno);
+ expectMapEmpty(testMap);
+ int entriesSeen = 0;
+ EXPECT_OK(testMap.iterate(
+ [&entriesSeen](const unsigned int&,
+ const BpfMap<unsigned int, unsigned int>&) -> netdutils::Status {
+ entriesSeen++;
+ return netdutils::status::ok;
+ }));
+ EXPECT_EQ(0, entriesSeen);
+ EXPECT_OK(testMap.iterateWithValue(
+ [&entriesSeen](const unsigned int&, const unsigned int&,
+ const BpfMap<unsigned int, unsigned int>&) -> netdutils::Status {
+ entriesSeen++;
+ return netdutils::status::ok;
+ }));
+ EXPECT_EQ(0, entriesSeen);
+}
+
+TEST_F(BpfMapTest, mapClear) {
+ BpfMap<uint32_t, uint32_t> testMap(mMapFd);
+ populateMap(TEST_MAP_SIZE, testMap);
+ auto isEmpty = testMap.isEmpty();
+ ASSERT_TRUE(isOk(isEmpty));
+ ASSERT_FALSE(isEmpty.value());
+ ASSERT_TRUE(isOk(testMap.clear()));
+ expectMapEmpty(testMap);
+}
+
+} // namespace bpf
+} // namespace android
diff --git a/libbpf/BpfUtils.cpp b/libbpf/BpfUtils.cpp
new file mode 100644
index 0000000..955f2ec
--- /dev/null
+++ b/libbpf/BpfUtils.cpp
@@ -0,0 +1,415 @@
+/*
+ * Copyright (C) 2017 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 LOG_TAG "BpfUtils"
+
+#include <elf.h>
+#include <inttypes.h>
+#include <linux/bpf.h>
+#include <linux/if_ether.h>
+#include <linux/in.h>
+#include <stdlib.h>
+#include <string.h>
+#include <sys/mman.h>
+#include <sys/socket.h>
+#include <sys/stat.h>
+#include <sys/utsname.h>
+#include <sstream>
+#include <string>
+
+#include <android-base/properties.h>
+#include <android-base/stringprintf.h>
+#include <android-base/unique_fd.h>
+#include <netdutils/MemBlock.h>
+#include <netdutils/Slice.h>
+#include <netdutils/StatusOr.h>
+#include "bpf/BpfUtils.h"
+
+using android::base::GetUintProperty;
+using android::base::StringPrintf;
+using android::base::unique_fd;
+using android::netdutils::MemBlock;
+using android::netdutils::Slice;
+using android::netdutils::statusFromErrno;
+using android::netdutils::StatusOr;
+
+constexpr size_t LOG_BUF_SIZE = 65536;
+
+namespace android {
+namespace bpf {
+
+/* The bpf_attr is a union which might have a much larger size then the struct we are using, while
+ * The inline initializer only reset the field we are using and leave the reset of the memory as
+ * is. The bpf kernel code will performs a much stricter check to ensure all unused field is 0. So
+ * this syscall will normally fail with E2BIG if we don't do a memset to bpf_attr.
+ */
+bool operator==(const StatsKey& lhs, const StatsKey& rhs) {
+ return ((lhs.uid == rhs.uid) && (lhs.tag == rhs.tag) && (lhs.counterSet == rhs.counterSet) &&
+ (lhs.ifaceIndex == rhs.ifaceIndex));
+}
+
+bool operator==(const UidTag& lhs, const UidTag& rhs) {
+ return ((lhs.uid == rhs.uid) && (lhs.tag == rhs.tag));
+}
+
+bool operator==(const StatsValue& lhs, const StatsValue& rhs) {
+ return ((lhs.rxBytes == rhs.rxBytes) && (lhs.txBytes == rhs.txBytes) &&
+ (lhs.rxPackets == rhs.rxPackets) && (lhs.txPackets == rhs.txPackets));
+}
+
+int bpf(int cmd, Slice bpfAttr) {
+ return syscall(__NR_bpf, cmd, bpfAttr.base(), bpfAttr.size());
+}
+
+int createMap(bpf_map_type map_type, uint32_t key_size, uint32_t value_size, uint32_t max_entries,
+ uint32_t map_flags) {
+ bpf_attr attr;
+ memset(&attr, 0, sizeof(attr));
+ attr.map_type = map_type;
+ attr.key_size = key_size;
+ attr.value_size = value_size;
+ attr.max_entries = max_entries;
+ attr.map_flags = map_flags;
+
+ return bpf(BPF_MAP_CREATE, Slice(&attr, sizeof(attr)));
+}
+
+int writeToMapEntry(const base::unique_fd& map_fd, void* key, void* value, uint64_t flags) {
+ bpf_attr attr;
+ memset(&attr, 0, sizeof(attr));
+ attr.map_fd = map_fd.get();
+ attr.key = ptr_to_u64(key);
+ attr.value = ptr_to_u64(value);
+ attr.flags = flags;
+
+ return bpf(BPF_MAP_UPDATE_ELEM, Slice(&attr, sizeof(attr)));
+}
+
+int findMapEntry(const base::unique_fd& map_fd, void* key, void* value) {
+ bpf_attr attr;
+ memset(&attr, 0, sizeof(attr));
+ attr.map_fd = map_fd.get();
+ attr.key = ptr_to_u64(key);
+ attr.value = ptr_to_u64(value);
+
+ return bpf(BPF_MAP_LOOKUP_ELEM, Slice(&attr, sizeof(attr)));
+}
+
+int deleteMapEntry(const base::unique_fd& map_fd, void* key) {
+ bpf_attr attr;
+ memset(&attr, 0, sizeof(attr));
+ attr.map_fd = map_fd.get();
+ attr.key = ptr_to_u64(key);
+
+ return bpf(BPF_MAP_DELETE_ELEM, Slice(&attr, sizeof(attr)));
+}
+
+int getNextMapKey(const base::unique_fd& map_fd, void* key, void* next_key) {
+ bpf_attr attr;
+ memset(&attr, 0, sizeof(attr));
+ attr.map_fd = map_fd.get();
+ attr.key = ptr_to_u64(key);
+ attr.next_key = ptr_to_u64(next_key);
+
+ return bpf(BPF_MAP_GET_NEXT_KEY, Slice(&attr, sizeof(attr)));
+}
+
+int getFirstMapKey(const base::unique_fd& map_fd, void* firstKey) {
+ bpf_attr attr;
+ memset(&attr, 0, sizeof(attr));
+ attr.map_fd = map_fd.get();
+ attr.key = 0;
+ attr.next_key = ptr_to_u64(firstKey);
+
+ return bpf(BPF_MAP_GET_NEXT_KEY, Slice(&attr, sizeof(attr)));
+}
+
+int bpfProgLoad(bpf_prog_type prog_type, Slice bpf_insns, const char* license,
+ uint32_t kern_version, Slice bpf_log) {
+ bpf_attr attr;
+ memset(&attr, 0, sizeof(attr));
+ attr.prog_type = prog_type;
+ attr.insns = ptr_to_u64(bpf_insns.base());
+ attr.insn_cnt = bpf_insns.size() / sizeof(struct bpf_insn);
+ attr.license = ptr_to_u64((void*)license);
+ attr.log_buf = ptr_to_u64(bpf_log.base());
+ attr.log_size = bpf_log.size();
+ attr.log_level = DEFAULT_LOG_LEVEL;
+ attr.kern_version = kern_version;
+ int ret = bpf(BPF_PROG_LOAD, Slice(&attr, sizeof(attr)));
+
+ if (ret < 0) {
+ std::string prog_log = netdutils::toString(bpf_log);
+ std::istringstream iss(prog_log);
+ for (std::string line; std::getline(iss, line);) {
+ ALOGE("%s", line.c_str());
+ }
+ }
+ return ret;
+}
+
+int bpfFdPin(const base::unique_fd& map_fd, const char* pathname) {
+ bpf_attr attr;
+ memset(&attr, 0, sizeof(attr));
+ attr.pathname = ptr_to_u64((void*)pathname);
+ attr.bpf_fd = map_fd.get();
+
+ return bpf(BPF_OBJ_PIN, Slice(&attr, sizeof(attr)));
+}
+
+int mapRetrieve(const char* pathname, uint32_t flag) {
+ bpf_attr attr;
+ memset(&attr, 0, sizeof(attr));
+ attr.pathname = ptr_to_u64((void*)pathname);
+ attr.file_flags = flag;
+ return bpf(BPF_OBJ_GET, Slice(&attr, sizeof(attr)));
+}
+
+int attachProgram(bpf_attach_type type, uint32_t prog_fd, uint32_t cg_fd) {
+ bpf_attr attr;
+ memset(&attr, 0, sizeof(attr));
+ attr.target_fd = cg_fd;
+ attr.attach_bpf_fd = prog_fd;
+ attr.attach_type = type;
+
+ return bpf(BPF_PROG_ATTACH, Slice(&attr, sizeof(attr)));
+}
+
+int detachProgram(bpf_attach_type type, uint32_t cg_fd) {
+ bpf_attr attr;
+ memset(&attr, 0, sizeof(attr));
+ attr.target_fd = cg_fd;
+ attr.attach_type = type;
+
+ return bpf(BPF_PROG_DETACH, Slice(&attr, sizeof(attr)));
+}
+
+uint64_t getSocketCookie(int sockFd) {
+ uint64_t sock_cookie;
+ socklen_t cookie_len = sizeof(sock_cookie);
+ int res = getsockopt(sockFd, SOL_SOCKET, SO_COOKIE, &sock_cookie, &cookie_len);
+ if (res < 0) {
+ res = -errno;
+ ALOGE("Failed to get socket cookie: %s\n", strerror(errno));
+ errno = -res;
+ // 0 is an invalid cookie. See sock_gen_cookie.
+ return NONEXISTENT_COOKIE;
+ }
+ return sock_cookie;
+}
+
+bool hasBpfSupport() {
+ struct utsname buf;
+ int kernel_version_major;
+ int kernel_version_minor;
+
+ uint64_t api_level = GetUintProperty<uint64_t>("ro.product.first_api_level", 0);
+ if (api_level == 0) {
+ ALOGE("Cannot determine initial API level of the device");
+ api_level = GetUintProperty<uint64_t>("ro.build.version.sdk", 0);
+ }
+
+ int ret = uname(&buf);
+ if (ret) {
+ return false;
+ }
+ char dummy;
+ ret = sscanf(buf.release, "%d.%d%c", &kernel_version_major, &kernel_version_minor, &dummy);
+ if (ret >= 2 && ((kernel_version_major > 4) ||
+ (kernel_version_major == 4 && kernel_version_minor >= 9))) {
+ // Check if the device is shipped originally with android P.
+ return api_level >= MINIMUM_API_REQUIRED;
+ }
+ return false;
+}
+
+int loadAndPinProgram(BpfProgInfo* prog, Slice progBlock) {
+ // Program doesn't exist. Try to load it.
+ char bpf_log_buf[LOG_BUF_SIZE];
+ Slice bpfLog = Slice(bpf_log_buf, sizeof(bpf_log_buf));
+ prog->fd.reset(bpfProgLoad(prog->loadType, progBlock, "Apache 2.0", 0, bpfLog));
+ if (prog->fd < 0) {
+ int ret = -errno;
+ ALOGE("load %s failed: %s", prog->name, strerror(errno));
+ return ret;
+ }
+ if (prog->attachType == BPF_CGROUP_INET_EGRESS || prog->attachType == BPF_CGROUP_INET_INGRESS) {
+ unique_fd cg_fd(open(CGROUP_ROOT_PATH, O_DIRECTORY | O_RDONLY | O_CLOEXEC));
+ if (cg_fd < 0) {
+ int ret = -errno;
+ ALOGE("Failed to open the cgroup directory");
+ return ret;
+ }
+ int ret = android::bpf::attachProgram(prog->attachType, prog->fd, cg_fd);
+ if (ret) {
+ ret = -errno;
+ ALOGE("%s attach failed: %s", prog->name, strerror(errno));
+ return ret;
+ }
+ }
+ if (prog->path) {
+ int ret = android::bpf::bpfFdPin(prog->fd, prog->path);
+ if (ret) {
+ ret = -errno;
+ ALOGE("Pin %s as file %s failed: %s", prog->name, prog->path, strerror(errno));
+ return ret;
+ }
+ }
+ return 0;
+}
+
+int extractAndLoadProg(BpfProgInfo* prog, Elf64_Shdr* sectionPtr, Slice fileContents,
+ const std::vector<BpfMapInfo>& mapPatterns) {
+ uint64_t progSize = (uint64_t) sectionPtr->sh_size;
+ Slice progSection = take(drop(fileContents, sectionPtr->sh_offset), progSize);
+ if (progSection.size() < progSize) {
+ ALOGE("programSection out of bound");
+ return -EINVAL;
+ }
+ MemBlock progCopy(progSection);
+ if (progCopy.get().size() != progSize) {
+ ALOGE("program cannot be extracted");
+ return -EINVAL;
+ }
+ Slice remaining = progCopy.get();
+ while (remaining.size() >= MAP_CMD_SIZE) {
+ // Scan the program, examining all possible places that might be the start of a
+ // map load operation (i.e., all bytes of value MAP_LD_CMD_HEAD).
+ // In each of these places, check whether it is the start of one of the patterns
+ // we want to replace, and if so, replace it.
+ Slice mapHead = findFirstMatching(remaining, MAP_LD_CMD_HEAD);
+ if (mapHead.size() < MAP_CMD_SIZE) break;
+ bool replaced = false;
+ for (const auto& pattern : mapPatterns) {
+ if (!memcmp(mapHead.base(), pattern.search.data(), MAP_CMD_SIZE)) {
+ memcpy(mapHead.base(), pattern.replace.data(), MAP_CMD_SIZE);
+ replaced = true;
+ break;
+ }
+ }
+ remaining = drop(mapHead, replaced ? MAP_CMD_SIZE : sizeof(uint8_t));
+ }
+ if (!(prog->path) || access(prog->path, R_OK) == -1) {
+ return loadAndPinProgram(prog, progCopy.get());
+ }
+ return 0;
+}
+
+int parsePrograms(Slice fileContents, BpfProgInfo* programs, size_t size,
+ const std::vector<BpfMapInfo>& mapPatterns) {
+ Slice elfHeader = take(fileContents, sizeof(Elf64_Ehdr));
+ if (elfHeader.size() < sizeof(Elf64_Ehdr)) {
+ ALOGE("bpf fileContents does not have complete elf header");
+ return -EINVAL;
+ }
+
+ Elf64_Ehdr* elf = (Elf64_Ehdr*) elfHeader.base();
+ // Find section names string table. This is the section whose index is e_shstrndx.
+ if (elf->e_shstrndx == SHN_UNDEF) {
+ ALOGE("cannot locate namesSection\n");
+ return -EINVAL;
+ }
+ size_t totalSectionSize = (elf->e_shnum) * sizeof(Elf64_Shdr);
+ Slice sections = take(drop(fileContents, elf->e_shoff), totalSectionSize);
+ if (sections.size() < totalSectionSize) {
+ ALOGE("sections corrupted");
+ return -EMSGSIZE;
+ }
+
+ Slice namesSection =
+ take(drop(sections, elf->e_shstrndx * sizeof(Elf64_Shdr)), sizeof(Elf64_Shdr));
+ if (namesSection.size() != sizeof(Elf64_Shdr)) {
+ ALOGE("namesSection corrupted");
+ return -EMSGSIZE;
+ }
+ size_t strTabOffset = ((Elf64_Shdr*) namesSection.base())->sh_offset;
+ size_t strTabSize = ((Elf64_Shdr*) namesSection.base())->sh_size;
+
+ Slice strTab = take(drop(fileContents, strTabOffset), strTabSize);
+ if (strTab.size() < strTabSize) {
+ ALOGE("string table out of bound\n");
+ return -EMSGSIZE;
+ }
+
+ for (int i = 0; i < elf->e_shnum; i++) {
+ Slice section = take(drop(sections, i * sizeof(Elf64_Shdr)), sizeof(Elf64_Shdr));
+ if (section.size() < sizeof(Elf64_Shdr)) {
+ ALOGE("section %d is out of bound, section size: %zu, header size: %zu, total size: "
+ "%zu",
+ i, section.size(), sizeof(Elf64_Shdr), sections.size());
+ return -EBADF;
+ }
+ Elf64_Shdr* sectionPtr = (Elf64_Shdr*) section.base();
+ Slice nameSlice = drop(strTab, sectionPtr->sh_name);
+ if (nameSlice.size() == 0) {
+ ALOGE("nameSlice out of bound, i: %d, strTabSize: %zu, sh_name: %u", i, strTabSize,
+ sectionPtr->sh_name);
+ return -EBADF;
+ }
+ for (size_t i = 0; i < size; i++) {
+ BpfProgInfo* prog = programs + i;
+ if (!strcmp((char*) nameSlice.base(), prog->name)) {
+ int ret = extractAndLoadProg(prog, sectionPtr, fileContents, mapPatterns);
+ if (ret) return ret;
+ }
+ }
+ }
+
+ // Check all the program struct passed in to make sure they all have a valid fd.
+ for (size_t i = 0; i < size; i++) {
+ BpfProgInfo* prog = programs + i;
+ if (access(prog->path, R_OK) == -1) {
+ ALOGE("Load program %s failed", prog->name);
+ return -EINVAL;
+ }
+ }
+ return 0;
+}
+
+int parseProgramsFromFile(const char* path, BpfProgInfo* programs, size_t size,
+ const std::vector<BpfMapInfo>& mapPatterns) {
+ unique_fd fd(open(path, O_RDONLY));
+ int ret;
+ if (fd < 0) {
+ ret = -errno;
+ ALOGE("Failed to open %s program: %s", path, strerror(errno));
+ return ret;
+ }
+
+ struct stat stat;
+ if (fstat(fd.get(), &stat)) {
+ ret = -errno;
+ ALOGE("Failed to get file (%s) size: %s", path, strerror(errno));
+ return ret;
+ }
+
+ off_t fileLen = stat.st_size;
+ char* baseAddr =
+ (char*) mmap(NULL, fileLen, PROT_READ, MAP_PRIVATE | MAP_POPULATE, fd.get(), 0);
+ if (baseAddr == MAP_FAILED) {
+ ALOGE("Failed to map the program (%s) into memory: %s", path, strerror(errno));
+ ret = -errno;
+ return ret;
+ }
+
+ ret = parsePrograms(Slice(baseAddr, fileLen), programs, size, mapPatterns);
+
+ munmap(baseAddr, fileLen);
+ return ret;
+}
+
+} // namespace bpf
+} // namespace android
diff --git a/libbpf/include/bpf/BpfMap.h b/libbpf/include/bpf/BpfMap.h
new file mode 100644
index 0000000..20db43e
--- /dev/null
+++ b/libbpf/include/bpf/BpfMap.h
@@ -0,0 +1,284 @@
+/*
+ * Copyright (C) 2018 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.
+ */
+
+#ifndef BPF_BPFMAP_H
+#define BPF_BPFMAP_H
+
+#include <linux/bpf.h>
+
+#include <android-base/stringprintf.h>
+#include <android-base/unique_fd.h>
+#include <utils/Log.h>
+#include "bpf/BpfUtils.h"
+#include "netdutils/Status.h"
+#include "netdutils/StatusOr.h"
+
+namespace android {
+namespace bpf {
+
+// This is a class wrapper for eBPF maps. The eBPF map is a special in-kernel
+// data structure that stores data in <Key, Value> pairs. It can be read/write
+// from userspace by passing syscalls with the map file descriptor. This class
+// is used to generalize the procedure of interacting with eBPF maps and hide
+// the implementation detail from other process. Besides the basic syscalls
+// wrapper, it also provides some useful helper functions as well as an iterator
+// nested class to iterate the map more easily.
+//
+// NOTE: A kernel eBPF map may be accessed by both kernel and userspace
+// processes at the same time. Or if the map is pinned as a virtual file, it can
+// be obtained by multiple eBPF map class object and accessed concurrently.
+// Though the map class object and the underlying kernel map are thread safe, it
+// is not safe to iterate over a map while another thread or process is deleting
+// from it. In this case the iteration can return duplicate entries.
+template <class Key, class Value>
+class BpfMap {
+ public:
+ BpfMap<Key, Value>() : mMapFd(-1){};
+ BpfMap<Key, Value>(int fd) : mMapFd(fd){};
+ BpfMap<Key, Value>(bpf_map_type map_type, uint32_t max_entries, uint32_t map_flags) {
+ int map_fd = createMap(map_type, sizeof(Key), sizeof(Value), max_entries, map_flags);
+ if (map_fd < 0) {
+ mMapFd.reset(-1);
+ } else {
+ mMapFd.reset(map_fd);
+ }
+ }
+
+ netdutils::Status pinToPath(const std::string path) {
+ int ret = bpfFdPin(mMapFd, path.c_str());
+ if (ret) {
+ return netdutils::statusFromErrno(errno,
+ base::StringPrintf("pin to %s failed", path.c_str()));
+ }
+ mPinnedPath = path;
+ return netdutils::status::ok;
+ }
+
+ netdutils::StatusOr<Key> getFirstKey() const {
+ Key firstKey;
+ if (getFirstMapKey(mMapFd, &firstKey)) {
+ return netdutils::statusFromErrno(
+ errno, base::StringPrintf("Get firstKey map %d failed", mMapFd.get()));
+ }
+ return firstKey;
+ }
+
+ netdutils::StatusOr<Key> getNextKey(const Key& key) const {
+ Key nextKey;
+ if (getNextMapKey(mMapFd, const_cast<Key*>(&key), &nextKey)) {
+ return netdutils::statusFromErrno(
+ errno, base::StringPrintf("Get next key of map %d failed", mMapFd.get()));
+ }
+ return nextKey;
+ }
+
+ netdutils::Status writeValue(const Key& key, const Value& value, uint64_t flags) {
+ if (writeToMapEntry(mMapFd, const_cast<Key*>(&key), const_cast<Value*>(&value), flags)) {
+ return netdutils::statusFromErrno(
+ errno, base::StringPrintf("write to map %d failed", mMapFd.get()));
+ }
+ return netdutils::status::ok;
+ }
+
+ netdutils::StatusOr<Value> readValue(const Key key) const {
+ Value value;
+ if (findMapEntry(mMapFd, const_cast<Key*>(&key), &value)) {
+ return netdutils::statusFromErrno(
+ errno, base::StringPrintf("read value of map %d failed", mMapFd.get()));
+ }
+ return value;
+ }
+
+ netdutils::Status deleteValue(const Key& key) {
+ if (deleteMapEntry(mMapFd, const_cast<Key*>(&key))) {
+ return netdutils::statusFromErrno(
+ errno, base::StringPrintf("delete entry from map %d failed", mMapFd.get()));
+ }
+ return netdutils::status::ok;
+ }
+
+ // Function that tries to get map from a pinned path, if the map doesn't
+ // exist yet, create a new one and pinned to the path.
+ netdutils::Status getOrCreate(const uint32_t maxEntries, const char* path,
+ const bpf_map_type mapType);
+
+ // Iterate through the map and handle each key retrieved based on the filter
+ // without modification of map content.
+ netdutils::Status iterate(
+ const std::function<netdutils::Status(const Key& key, const BpfMap<Key, Value>& map)>&
+ filter) const;
+
+ // Iterate through the map and get each <key, value> pair, handle each <key,
+ // value> pair based on the filter without modification of map content.
+ netdutils::Status iterateWithValue(
+ const std::function<netdutils::Status(const Key& key, const Value& value,
+ const BpfMap<Key, Value>& map)>& filter) const;
+
+ // Iterate through the map and handle each key retrieved based on the filter
+ netdutils::Status iterate(
+ const std::function<netdutils::Status(const Key& key, BpfMap<Key, Value>& map)>& filter);
+
+ // Iterate through the map and get each <key, value> pair, handle each <key,
+ // value> pair based on the filter.
+ netdutils::Status iterateWithValue(
+ const std::function<netdutils::Status(const Key& key, const Value& value,
+ BpfMap<Key, Value>& map)>& filter);
+
+ const base::unique_fd& getMap() const { return mMapFd; };
+
+ const std::string getPinnedPath() const { return mPinnedPath; };
+
+ // Move constructor
+ void operator=(BpfMap<Key, Value>&& other) noexcept {
+ mMapFd = std::move(other.mMapFd);
+ if (!other.mPinnedPath.empty()) {
+ mPinnedPath = other.mPinnedPath;
+ } else {
+ mPinnedPath.clear();
+ }
+ other.reset();
+ }
+
+ void reset(int fd = -1) {
+ mMapFd.reset(fd);
+ mPinnedPath.clear();
+ }
+
+ bool isValid() const { return mMapFd != -1; }
+
+ // It is only safe to call this method if it is guaranteed that nothing will concurrently
+ // iterate over the map in any process.
+ netdutils::Status clear() {
+ const auto deleteAllEntries = [](const Key& key, BpfMap<Key, Value>& map) {
+ netdutils::Status res = map.deleteValue(key);
+ if (!isOk(res) && (res.code() != ENOENT)) {
+ ALOGE("Failed to delete data %s\n", strerror(res.code()));
+ }
+ return netdutils::status::ok;
+ };
+ RETURN_IF_NOT_OK(iterate(deleteAllEntries));
+ return netdutils::status::ok;
+ }
+
+ netdutils::StatusOr<bool> isEmpty() const {
+ auto key = this->getFirstKey();
+ // Return error code ENOENT means the map is empty
+ if (!isOk(key) && key.status().code() == ENOENT) return true;
+ RETURN_IF_NOT_OK(key);
+ return false;
+ }
+
+ private:
+ base::unique_fd mMapFd;
+ std::string mPinnedPath;
+};
+
+template <class Key, class Value>
+netdutils::Status BpfMap<Key, Value>::getOrCreate(const uint32_t maxEntries, const char* path,
+ bpf_map_type mapType) {
+ int ret = access(path, R_OK);
+ /* Check the pinned location first to check if the map is already there.
+ * otherwise create a new one.
+ */
+ if (ret == 0) {
+ mMapFd = base::unique_fd(mapRetrieve(path, 0));
+ if (mMapFd == -1) {
+ reset();
+ return netdutils::statusFromErrno(
+ errno,
+ base::StringPrintf("pinned map not accessible or does not exist: (%s)\n", path));
+ }
+ mPinnedPath = path;
+ } else if (ret == -1 && errno == ENOENT) {
+ mMapFd = base::unique_fd(
+ createMap(mapType, sizeof(Key), sizeof(Value), maxEntries, BPF_F_NO_PREALLOC));
+ if (mMapFd == -1) {
+ reset();
+ return netdutils::statusFromErrno(errno,
+ base::StringPrintf("map create failed!: %s", path));
+ }
+ netdutils::Status pinStatus = pinToPath(path);
+ if (!isOk(pinStatus)) {
+ reset();
+ return pinStatus;
+ }
+ mPinnedPath = path;
+ } else {
+ return netdutils::statusFromErrno(
+ errno, base::StringPrintf("pinned map not accessible: %s", path));
+ }
+ return netdutils::status::ok;
+}
+
+template <class Key, class Value>
+netdutils::Status BpfMap<Key, Value>::iterate(
+ const std::function<netdutils::Status(const Key& key, const BpfMap<Key, Value>& map)>& filter)
+ const {
+ netdutils::StatusOr<Key> curKey = getFirstKey();
+ while (isOk(curKey)) {
+ const netdutils::StatusOr<Key>& nextKey = getNextKey(curKey.value());
+ RETURN_IF_NOT_OK(filter(curKey.value(), *this));
+ curKey = nextKey;
+ }
+ return curKey.status().code() == ENOENT ? netdutils::status::ok : curKey.status();
+}
+
+template <class Key, class Value>
+netdutils::Status BpfMap<Key, Value>::iterateWithValue(
+ const std::function<netdutils::Status(const Key& key, const Value& value,
+ const BpfMap<Key, Value>& map)>& filter) const {
+ netdutils::StatusOr<Key> curKey = getFirstKey();
+ while (isOk(curKey)) {
+ const netdutils::StatusOr<Key>& nextKey = getNextKey(curKey.value());
+ Value curValue;
+ ASSIGN_OR_RETURN(curValue, this->readValue(curKey.value()));
+ RETURN_IF_NOT_OK(filter(curKey.value(), curValue, *this));
+ curKey = nextKey;
+ }
+ return curKey.status().code() == ENOENT ? netdutils::status::ok : curKey.status();
+}
+
+template <class Key, class Value>
+netdutils::Status BpfMap<Key, Value>::iterate(
+ const std::function<netdutils::Status(const Key& key, BpfMap<Key, Value>& map)>& filter) {
+ netdutils::StatusOr<Key> curKey = getFirstKey();
+ while (isOk(curKey)) {
+ const netdutils::StatusOr<Key>& nextKey = getNextKey(curKey.value());
+ RETURN_IF_NOT_OK(filter(curKey.value(), *this));
+ curKey = nextKey;
+ }
+ return curKey.status().code() == ENOENT ? netdutils::status::ok : curKey.status();
+}
+
+template <class Key, class Value>
+netdutils::Status BpfMap<Key, Value>::iterateWithValue(
+ const std::function<netdutils::Status(const Key& key, const Value& value,
+ BpfMap<Key, Value>& map)>& filter) {
+ netdutils::StatusOr<Key> curKey = getFirstKey();
+ while (isOk(curKey)) {
+ const netdutils::StatusOr<Key>& nextKey = getNextKey(curKey.value());
+ Value curValue;
+ ASSIGN_OR_RETURN(curValue, this->readValue(curKey.value()));
+ RETURN_IF_NOT_OK(filter(curKey.value(), curValue, *this));
+ curKey = nextKey;
+ }
+ return curKey.status().code() == ENOENT ? netdutils::status::ok : curKey.status();
+}
+
+} // namespace bpf
+} // namespace android
+
+#endif
diff --git a/libbpf/include/bpf/BpfUtils.h b/libbpf/include/bpf/BpfUtils.h
new file mode 100644
index 0000000..ed31758
--- /dev/null
+++ b/libbpf/include/bpf/BpfUtils.h
@@ -0,0 +1,168 @@
+/*
+ * Copyright (C) 2017 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.
+ */
+
+#ifndef BPF_BPFUTILS_H
+#define BPF_BPFUTILS_H
+
+#include <linux/bpf.h>
+#include <linux/if_ether.h>
+#include <linux/in.h>
+#include <linux/unistd.h>
+#include <net/if.h>
+#include <stdlib.h>
+#include <string.h>
+#include <sys/socket.h>
+
+#include "android-base/unique_fd.h"
+#include "netdutils/Slice.h"
+#include "netdutils/StatusOr.h"
+
+#define BPF_PASS 1
+#define BPF_DROP 0
+
+#define ptr_to_u64(x) ((uint64_t)(uintptr_t)(x))
+#define DEFAULT_LOG_LEVEL 1
+
+#define MAP_LD_CMD_HEAD 0x18
+#define ARRAY_SIZE(a) (sizeof(a) / sizeof(*(a)))
+
+// The BPF instruction bytes that we need to replace. x is a placeholder (e.g., COOKIE_TAG_MAP).
+#define BPF_MAP_SEARCH_PATTERN(x) \
+ { \
+ 0x18, 0x01, 0x00, 0x00, \
+ (x)[0], (x)[1], (x)[2], (x)[3], \
+ 0x00, 0x00, 0x00, 0x00, \
+ (x)[4], (x)[5], (x)[6], (x)[7] \
+ }
+
+// The bytes we'll replace them with. x is the actual fd number for the map at runtime.
+// The second byte is changed from 0x01 to 0x11 since 0x11 is the special command used
+// for bpf map fd loading. The original 0x01 is only a normal load command.
+#define BPF_MAP_REPLACE_PATTERN(x) \
+ { \
+ 0x18, 0x11, 0x00, 0x00, \
+ (x)[0], (x)[1], (x)[2], (x)[3], \
+ 0x00, 0x00, 0x00, 0x00, \
+ (x)[4], (x)[5], (x)[6], (x)[7] \
+ }
+
+#define MAP_CMD_SIZE 16
+
+namespace android {
+namespace bpf {
+
+struct UidTag {
+ uint32_t uid;
+ uint32_t tag;
+};
+
+struct StatsKey {
+ uint32_t uid;
+ uint32_t tag;
+ uint32_t counterSet;
+ uint32_t ifaceIndex;
+};
+
+struct StatsValue {
+ uint64_t rxPackets;
+ uint64_t rxBytes;
+ uint64_t txPackets;
+ uint64_t txBytes;
+};
+
+struct Stats {
+ uint64_t rxBytes;
+ uint64_t rxPackets;
+ uint64_t txBytes;
+ uint64_t txPackets;
+ uint64_t tcpRxPackets;
+ uint64_t tcpTxPackets;
+};
+
+struct IfaceValue {
+ char name[IFNAMSIZ];
+};
+
+struct BpfProgInfo {
+ bpf_attach_type attachType;
+ const char* path;
+ const char* name;
+ bpf_prog_type loadType;
+ base::unique_fd fd;
+};
+
+int mapRetrieve(const char* pathname, uint32_t flags);
+
+struct BpfMapInfo {
+ std::array<uint8_t, MAP_CMD_SIZE> search;
+ std::array<uint8_t, MAP_CMD_SIZE> replace;
+ const int fd;
+ std::string path;
+
+ BpfMapInfo(uint64_t dummyFd, const char* mapPath)
+ : BpfMapInfo(dummyFd, android::bpf::mapRetrieve(mapPath, 0)) {}
+
+ BpfMapInfo(uint64_t dummyFd, int realFd, const char* mapPath = "") : fd(realFd), path(mapPath) {
+ search = BPF_MAP_SEARCH_PATTERN((uint8_t*) &dummyFd);
+ replace = BPF_MAP_REPLACE_PATTERN((uint8_t*) &realFd);
+ }
+};
+
+#ifndef DEFAULT_OVERFLOWUID
+#define DEFAULT_OVERFLOWUID 65534
+#endif
+
+constexpr const char* CGROUP_ROOT_PATH = "/dev/cg2_bpf";
+
+constexpr const int OVERFLOW_COUNTERSET = 2;
+
+constexpr const uint64_t NONEXISTENT_COOKIE = 0;
+
+constexpr const int MINIMUM_API_REQUIRED = 28;
+
+int createMap(bpf_map_type map_type, uint32_t key_size, uint32_t value_size,
+ uint32_t max_entries, uint32_t map_flags);
+int writeToMapEntry(const base::unique_fd& map_fd, void* key, void* value, uint64_t flags);
+int findMapEntry(const base::unique_fd& map_fd, void* key, void* value);
+int deleteMapEntry(const base::unique_fd& map_fd, void* key);
+int getNextMapKey(const base::unique_fd& map_fd, void* key, void* next_key);
+int getFirstMapKey(const base::unique_fd& map_fd, void* firstKey);
+int bpfProgLoad(bpf_prog_type prog_type, netdutils::Slice bpf_insns, const char* license,
+ uint32_t kern_version, netdutils::Slice bpf_log);
+int bpfFdPin(const base::unique_fd& map_fd, const char* pathname);
+int attachProgram(bpf_attach_type type, uint32_t prog_fd, uint32_t cg_fd);
+int detachProgram(bpf_attach_type type, uint32_t cg_fd);
+uint64_t getSocketCookie(int sockFd);
+bool hasBpfSupport();
+int parseProgramsFromFile(const char* path, BpfProgInfo* programs, size_t size,
+ const std::vector<BpfMapInfo>& mapPatterns);
+
+#define SKIP_IF_BPF_NOT_SUPPORTED \
+ do { \
+ if (!hasBpfSupport()) return; \
+ } while (0)
+
+constexpr int BPF_CONTINUE = 0;
+constexpr int BPF_DELETED = 1;
+
+bool operator==(const StatsValue& lhs, const StatsValue& rhs);
+bool operator==(const UidTag& lhs, const UidTag& rhs);
+bool operator==(const StatsKey& lhs, const StatsKey& rhs);
+
+} // namespace bpf
+} // namespace android
+
+#endif
