Add NetworkTraceHandler with Start/Stop/ConsumeAll
This adds the base (non-perfetto) NetworkTraceHandler with support for
starting and stopping tracing, and pulling messages from BPF. The
included test covers the end-to-end scenario from socket creation,
socket tagging and data traffic.
Bug: 246985031
Test: atest --iterations 500 libnetworkstats_test
Change-Id: I035d2e03fa7c461ecb93d207b7fd2f53e6a2f52e
diff --git a/service-t/native/libs/libnetworkstats/Android.bp b/service-t/native/libs/libnetworkstats/Android.bp
index 5b3d314..5cb27e6 100644
--- a/service-t/native/libs/libnetworkstats/Android.bp
+++ b/service-t/native/libs/libnetworkstats/Android.bp
@@ -24,7 +24,8 @@
host_supported: false,
header_libs: ["bpf_connectivity_headers"],
srcs: [
- "BpfNetworkStats.cpp"
+ "BpfNetworkStats.cpp",
+ "NetworkTraceHandler.cpp",
],
shared_libs: [
"libbase",
@@ -54,6 +55,7 @@
header_libs: ["bpf_connectivity_headers"],
srcs: [
"BpfNetworkStatsTest.cpp",
+ "NetworkTraceHandlerTest.cpp",
],
cflags: [
"-Wall",
@@ -68,6 +70,7 @@
shared_libs: [
"libbase",
"liblog",
+ "libandroid_net",
],
compile_multilib: "both",
multilib: {
diff --git a/service-t/native/libs/libnetworkstats/NetworkTraceHandler.cpp b/service-t/native/libs/libnetworkstats/NetworkTraceHandler.cpp
new file mode 100644
index 0000000..c679357
--- /dev/null
+++ b/service-t/native/libs/libnetworkstats/NetworkTraceHandler.cpp
@@ -0,0 +1,83 @@
+/*
+ * Copyright (C) 2023 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 "NetworkTrace"
+
+#include "netdbpf/NetworkTraceHandler.h"
+
+#include <bpf/BpfUtils.h>
+#include <log/log.h>
+
+namespace android {
+namespace bpf {
+
+bool NetworkTraceHandler::Start() {
+ ALOGD("Starting datasource");
+
+ auto status = mConfigurationMap.init(PACKET_TRACE_ENABLED_MAP_PATH);
+ if (!status.ok()) {
+ ALOGW("Failed to bind config map: %s", status.error().message().c_str());
+ return false;
+ }
+
+ auto rb = BpfRingbuf<PacketTrace>::Create(PACKET_TRACE_RINGBUF_PATH);
+ if (!rb.ok()) {
+ ALOGW("Failed to create ringbuf: %s", rb.error().message().c_str());
+ return false;
+ }
+
+ mRingBuffer = std::move(*rb);
+
+ auto res = mConfigurationMap.writeValue(0, true, BPF_ANY);
+ if (!res.ok()) {
+ ALOGW("Failed to enable tracing: %s", res.error().message().c_str());
+ return false;
+ }
+
+ return true;
+}
+
+bool NetworkTraceHandler::Stop() {
+ ALOGD("Stopping datasource");
+
+ auto res = mConfigurationMap.writeValue(0, false, BPF_ANY);
+ if (!res.ok()) {
+ ALOGW("Failed to disable tracing: %s", res.error().message().c_str());
+ return false;
+ }
+
+ mRingBuffer.reset();
+
+ return true;
+}
+
+bool NetworkTraceHandler::ConsumeAll() {
+ if (mRingBuffer == nullptr) {
+ ALOGW("Tracing is not active");
+ return false;
+ }
+
+ base::Result<int> ret = mRingBuffer->ConsumeAll(mCallback);
+ if (!ret.ok()) {
+ ALOGW("Failed to poll ringbuf: %s", ret.error().message().c_str());
+ return false;
+ }
+
+ return true;
+}
+
+} // namespace bpf
+} // namespace android
diff --git a/service-t/native/libs/libnetworkstats/NetworkTraceHandlerTest.cpp b/service-t/native/libs/libnetworkstats/NetworkTraceHandlerTest.cpp
new file mode 100644
index 0000000..760ae91
--- /dev/null
+++ b/service-t/native/libs/libnetworkstats/NetworkTraceHandlerTest.cpp
@@ -0,0 +1,198 @@
+/*
+ * Copyright (C) 2023 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 <android-base/unique_fd.h>
+#include <android/multinetwork.h>
+#include <arpa/inet.h>
+#include <gmock/gmock.h>
+#include <gtest/gtest.h>
+#include <inttypes.h>
+#include <net/if.h>
+#include <netinet/tcp.h>
+#include <sys/socket.h>
+#include <sys/types.h>
+#include <unistd.h>
+
+#include <vector>
+
+#include "netdbpf/NetworkTraceHandler.h"
+
+using ::testing::AllOf;
+using ::testing::AnyOf;
+using ::testing::Each;
+using ::testing::Eq;
+using ::testing::Field;
+using ::testing::Test;
+
+namespace android {
+namespace bpf {
+
+__be16 bindAndListen(int s) {
+ sockaddr_in sin = {.sin_family = AF_INET};
+ socklen_t len = sizeof(sin);
+ if (bind(s, (sockaddr*)&sin, sizeof(sin))) return 0;
+ if (listen(s, 1)) return 0;
+ if (getsockname(s, (sockaddr*)&sin, &len)) return 0;
+ return sin.sin_port;
+}
+
+// This takes tcp flag constants from the standard library and makes them usable
+// with the flags we get from BPF. The standard library flags are big endian
+// whereas the BPF flags are reported in host byte order. BPF also trims the
+// flags down to the 8 single-bit flag bits (fin, syn, rst, etc).
+constexpr inline uint8_t FlagToHost(__be32 be_unix_flags) {
+ return ntohl(be_unix_flags) >> 16;
+}
+
+// Pretty prints all fields for a list of packets (useful for debugging).
+struct PacketPrinter {
+ const std::vector<PacketTrace>& data;
+ static constexpr char kTcpFlagNames[] = "FSRPAUEC";
+
+ friend std::ostream& operator<<(std::ostream& os, const PacketPrinter& d) {
+ os << "Packet count: " << d.data.size();
+ for (const PacketTrace& info : d.data) {
+ os << "\nifidx=" << info.ifindex;
+ os << ", len=" << info.length;
+ os << ", uid=" << info.uid;
+ os << ", tag=" << info.tag;
+ os << ", sport=" << info.sport;
+ os << ", dport=" << info.dport;
+ os << ", direction=" << (info.egress ? "egress" : "ingress");
+ os << ", proto=" << static_cast<int>(info.ipProto);
+ os << ", ip=" << static_cast<int>(info.ipVersion);
+ os << ", flags=";
+ for (int i = 0; i < 8; i++) {
+ os << ((info.tcpFlags & (1 << i)) ? kTcpFlagNames[i] : '.');
+ }
+ }
+ return os;
+ }
+};
+
+class NetworkTraceHandlerTest : public testing::Test {
+ protected:
+ void SetUp() {
+ if (access(PACKET_TRACE_RINGBUF_PATH, R_OK)) {
+ GTEST_SKIP() << "Network tracing is not enabled/loaded on this build";
+ }
+ }
+};
+
+TEST_F(NetworkTraceHandlerTest, PollWhileInactive) {
+ NetworkTraceHandler handler([&](const PacketTrace& pkt) {});
+
+ // One succeed after start and before stop.
+ EXPECT_FALSE(handler.ConsumeAll());
+ ASSERT_TRUE(handler.Start());
+ EXPECT_TRUE(handler.ConsumeAll());
+ ASSERT_TRUE(handler.Stop());
+ EXPECT_FALSE(handler.ConsumeAll());
+}
+
+TEST_F(NetworkTraceHandlerTest, TraceTcpSession) {
+ __be16 server_port = 0;
+ std::vector<PacketTrace> packets;
+
+ // Record all packets with the bound address and current uid. This callback is
+ // involked only within ConsumeAll, at which point the port should have
+ // already been filled in and all packets have been processed.
+ NetworkTraceHandler handler([&](const PacketTrace& pkt) {
+ if (pkt.sport != server_port && pkt.dport != server_port) return;
+ if (pkt.uid != getuid()) return;
+ packets.push_back(pkt);
+ });
+
+ ASSERT_TRUE(handler.Start());
+ const uint32_t kClientTag = 2468;
+ const uint32_t kServerTag = 1357;
+
+ // Go through a typical connection sequence between two v4 sockets using tcp.
+ // This covers connection handshake, shutdown, and one data packet.
+ {
+ android::base::unique_fd clientsocket(socket(AF_INET, SOCK_STREAM, 0));
+ ASSERT_NE(-1, clientsocket) << "Failed to open client socket";
+ ASSERT_EQ(android_tag_socket(clientsocket, kClientTag), 0);
+
+ android::base::unique_fd serversocket(socket(AF_INET, SOCK_STREAM, 0));
+ ASSERT_NE(-1, serversocket) << "Failed to open server socket";
+ ASSERT_EQ(android_tag_socket(serversocket, kServerTag), 0);
+
+ server_port = bindAndListen(serversocket);
+ ASSERT_NE(0, server_port) << "Can't bind to server port";
+
+ sockaddr_in addr = {.sin_family = AF_INET, .sin_port = server_port};
+ ASSERT_EQ(0, connect(clientsocket, (sockaddr*)&addr, sizeof(addr)))
+ << "connect to loopback failed: " << strerror(errno);
+
+ int accepted = accept(serversocket, nullptr, nullptr);
+ ASSERT_NE(-1, accepted) << "accept connection failed: " << strerror(errno);
+
+ const char data[] = "abcdefghijklmnopqrstuvwxyz";
+ EXPECT_EQ(send(clientsocket, data, sizeof(data), 0), sizeof(data))
+ << "failed to send message: " << strerror(errno);
+
+ char buff[100] = {};
+ EXPECT_EQ(recv(accepted, buff, sizeof(buff), 0), sizeof(data))
+ << "failed to receive message: " << strerror(errno);
+
+ EXPECT_EQ(std::string(data), std::string(buff));
+ }
+
+ ASSERT_TRUE(handler.ConsumeAll());
+ ASSERT_TRUE(handler.Stop());
+
+ // There are 12 packets in total (6 messages: each seen by client & server):
+ // 1. Client connects to server with syn
+ // 2. Server responds with syn ack
+ // 3. Client responds with ack
+ // 4. Client sends data with psh ack
+ // 5. Server acks the data packet
+ // 6. Client closes connection with fin ack
+ ASSERT_EQ(packets.size(), 12) << PacketPrinter{packets};
+
+ // All packets should be TCP packets.
+ EXPECT_THAT(packets, Each(Field(&PacketTrace::ipProto, Eq(IPPROTO_TCP))));
+
+ // Packet 1: client requests connection with server.
+ EXPECT_EQ(packets[0].egress, 1) << PacketPrinter{packets};
+ EXPECT_EQ(packets[0].dport, server_port) << PacketPrinter{packets};
+ EXPECT_EQ(packets[0].tag, kClientTag) << PacketPrinter{packets};
+ EXPECT_EQ(packets[0].tcpFlags, FlagToHost(TCP_FLAG_SYN))
+ << PacketPrinter{packets};
+
+ // Packet 2: server receives request from client.
+ EXPECT_EQ(packets[1].egress, 0) << PacketPrinter{packets};
+ EXPECT_EQ(packets[1].dport, server_port) << PacketPrinter{packets};
+ EXPECT_EQ(packets[1].tag, kServerTag) << PacketPrinter{packets};
+ EXPECT_EQ(packets[1].tcpFlags, FlagToHost(TCP_FLAG_SYN))
+ << PacketPrinter{packets};
+
+ // Packet 3: server replies back with syn ack.
+ EXPECT_EQ(packets[2].egress, 1) << PacketPrinter{packets};
+ EXPECT_EQ(packets[2].sport, server_port) << PacketPrinter{packets};
+ EXPECT_EQ(packets[2].tcpFlags, FlagToHost(TCP_FLAG_SYN | TCP_FLAG_ACK))
+ << PacketPrinter{packets};
+
+ // Packet 4: client receives the server's syn ack.
+ EXPECT_EQ(packets[3].egress, 0) << PacketPrinter{packets};
+ EXPECT_EQ(packets[3].sport, server_port) << PacketPrinter{packets};
+ EXPECT_EQ(packets[3].tcpFlags, FlagToHost(TCP_FLAG_SYN | TCP_FLAG_ACK))
+ << PacketPrinter{packets};
+}
+
+} // namespace bpf
+} // namespace android
diff --git a/service-t/native/libs/libnetworkstats/include/netdbpf/NetworkTraceHandler.h b/service-t/native/libs/libnetworkstats/include/netdbpf/NetworkTraceHandler.h
new file mode 100644
index 0000000..67fcf41
--- /dev/null
+++ b/service-t/native/libs/libnetworkstats/include/netdbpf/NetworkTraceHandler.h
@@ -0,0 +1,54 @@
+/**
+ * Copyright (c) 2023, 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.
+ */
+
+#pragma once
+
+#include <string>
+#include <unordered_map>
+
+#include "bpf/BpfMap.h"
+#include "bpf/BpfRingbuf.h"
+
+// For PacketTrace struct definition
+#include "netd.h"
+
+namespace android {
+namespace bpf {
+
+class NetworkTraceHandler {
+ public:
+ // Initialize with a callback capable of intercepting data.
+ NetworkTraceHandler(std::function<void(const PacketTrace&)> callback)
+ : mCallback(std::move(callback)) {}
+
+ // Standalone functions without perfetto dependency.
+ bool Start();
+ bool Stop();
+ bool ConsumeAll();
+
+ private:
+ // The function to process PacketTrace, typically a Perfetto sink.
+ std::function<void(const PacketTrace&)> mCallback;
+
+ // The BPF ring buffer handle.
+ std::unique_ptr<BpfRingbuf<PacketTrace>> mRingBuffer;
+
+ // The packet tracing config map (really a 1-element array).
+ BpfMap<uint32_t, bool> mConfigurationMap;
+};
+
+} // namespace bpf
+} // namespace android