Add test for minadbd

Ass some unit tests to check if the minadbd service exit correctly in
the failure case. Also start the fuse and verify the socket communication
between minadbd with adb host, and minadbd with recovery.

Bug: 131037235
Test: run unit tests repeatedly, injects some errors and test fails
without dangling process.
Change-Id: I2f073b701b25d7f1aafc59868a7a91a8cbefaf49

minadbd/Android.bp

@@ -90,12 +90,14 @@ cc_test {
 
     srcs: [
         "fuse_adb_provider_test.cpp",
+        "minadbd_services_test.cpp",
     ],
 
     static_libs: [
         "libminadbd_services",
         "libfusesideload",
         "libadbd",
+        "libcrypto",
     ],
 
     shared_libs: [

minadbd/minadbd_services.cpp

@@ -50,6 +50,7 @@
 
 static int minadbd_socket = -1;
 static bool rescue_mode = false;
+static std::string sideload_mount_point = FUSE_SIDELOAD_HOST_MOUNTPOINT;
 
 void SetMinadbdSocketFd(int socket_fd) {
   minadbd_socket = socket_fd;
@@ -59,6 +60,10 @@ void SetMinadbdRescueMode(bool rescue) {
   rescue_mode = rescue;
 }
 
+void SetSideloadMountPoint(const std::string& path) {
+  sideload_mount_point = path;
+}
+
 static bool WriteCommandToFd(MinadbdCommands cmd, int fd) {
   char message[kMinadbdMessageSize];
   memcpy(message, kMinadbdCommandPrefix, strlen(kMinadbdStatusPrefix));
@@ -109,7 +114,8 @@ static MinadbdErrorCode RunAdbFuseSideload(int sfd, const std::string& args,
   }
 
   auto adb_data_reader = std::make_unique<FuseAdbDataProvider>(sfd, file_size, block_size);
-  if (int result = run_fuse_sideload(std::move(adb_data_reader)); result != 0) {
+  if (int result = run_fuse_sideload(std::move(adb_data_reader), sideload_mount_point.c_str());
+      result != 0) {
     LOG(ERROR) << "Failed to start fuse";
     return kMinadbdFuseStartError;
   }

minadbd/minadbd_services.h

@@ -16,6 +16,10 @@
 
 #pragma once
 
+#include <string>
+
 void SetMinadbdSocketFd(int socket_fd);
 
 void SetMinadbdRescueMode(bool);
+
+void SetSideloadMountPoint(const std::string& path);

minadbd/minadbd_services_test.cpp

@@ -0,0 +1,213 @@
+/*
+ * Copyright (C) 2019 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 <errno.h>
+#include <fcntl.h>
+#include <signal.h>
+#include <strings.h>
+#include <sys/mount.h>
+#include <sys/socket.h>
+#include <sys/stat.h>
+#include <sys/wait.h>
+#include <unistd.h>
+
+#include <string>
+#include <vector>
+
+#include <android-base/file.h>
+#include <android-base/unique_fd.h>
+#include <gtest/gtest.h>
+
+#include "adb.h"
+#include "adb_io.h"
+#include "fuse_adb_provider.h"
+#include "fuse_sideload.h"
+#include "minadbd_services.h"
+#include "minadbd_types.h"
+#include "socket.h"
+
+class MinadbdServicesTest : public ::testing::Test {
+ protected:
+  static constexpr int EXIT_TIME_OUT = 10;
+
+  void SetUp() override {
+    ASSERT_TRUE(
+        android::base::Socketpair(AF_UNIX, SOCK_STREAM, 0, &minadbd_socket_, &recovery_socket_));
+    SetMinadbdSocketFd(minadbd_socket_);
+    SetSideloadMountPoint(mount_point_.path);
+
+    package_path_ = std::string(mount_point_.path) + "/" + FUSE_SIDELOAD_HOST_FILENAME;
+    exit_flag_ = std::string(mount_point_.path) + "/" + FUSE_SIDELOAD_HOST_EXIT_FLAG;
+
+    signal(SIGPIPE, SIG_IGN);
+  }
+
+  void TearDown() override {
+    // Umount in case the test fails. Ignore the result.
+    umount(mount_point_.path);
+
+    signal(SIGPIPE, SIG_DFL);
+  }
+
+  void ReadAndCheckCommandMessage(int fd, MinadbdCommands expected_command) {
+    std::vector<uint8_t> received(kMinadbdMessageSize, '\0');
+    ASSERT_TRUE(android::base::ReadFully(fd, received.data(), kMinadbdMessageSize));
+
+    std::vector<uint8_t> expected(kMinadbdMessageSize, '\0');
+    memcpy(expected.data(), kMinadbdCommandPrefix, strlen(kMinadbdCommandPrefix));
+    memcpy(expected.data() + strlen(kMinadbdCommandPrefix), &expected_command,
+           sizeof(expected_command));
+    ASSERT_EQ(expected, received);
+  }
+
+  void WaitForFusePath() {
+    constexpr int TIME_OUT = 10;
+    for (int i = 0; i < TIME_OUT; ++i) {
+      struct stat sb;
+      if (stat(package_path_.c_str(), &sb) == 0) {
+        return;
+      }
+
+      if (errno == ENOENT) {
+        sleep(1);
+        continue;
+      }
+      FAIL() << "Timed out waiting for the fuse-provided package " << strerror(errno);
+    }
+  }
+
+  void StatExitFlagAndExitProcess(int exit_code) {
+    struct stat sb;
+    if (stat(exit_flag_.c_str(), &sb) != 0) {
+      PLOG(ERROR) << "Failed to stat " << exit_flag_;
+    }
+
+    exit(exit_code);
+  }
+
+  void WriteMinadbdCommandStatus(MinadbdCommandStatus status) {
+    std::string status_message(kMinadbdMessageSize, '\0');
+    memcpy(status_message.data(), kMinadbdStatusPrefix, strlen(kMinadbdStatusPrefix));
+    memcpy(status_message.data() + strlen(kMinadbdStatusPrefix), &status, sizeof(status));
+    ASSERT_TRUE(
+        android::base::WriteFully(recovery_socket_, status_message.data(), kMinadbdMessageSize));
+  }
+
+  void ExecuteCommandAndWaitForExit(const std::string& command) {
+    unique_fd fd = daemon_service_to_fd(command, nullptr);
+    ASSERT_NE(-1, fd);
+    sleep(EXIT_TIME_OUT);
+  }
+
+  android::base::unique_fd minadbd_socket_;
+  android::base::unique_fd recovery_socket_;
+
+  TemporaryDir mount_point_;
+  std::string package_path_;
+  std::string exit_flag_;
+};
+
+TEST_F(MinadbdServicesTest, SideloadHostService_wrong_size_argument) {
+  ASSERT_EXIT(ExecuteCommandAndWaitForExit("sideload-host:abc:4096"),
+              ::testing::ExitedWithCode(kMinadbdPackageSizeError), "");
+}
+
+TEST_F(MinadbdServicesTest, SideloadHostService_wrong_block_size) {
+  ASSERT_EXIT(ExecuteCommandAndWaitForExit("sideload-host:10:20"),
+              ::testing::ExitedWithCode(kMinadbdFuseStartError), "");
+}
+
+TEST_F(MinadbdServicesTest, SideloadHostService_broken_minadbd_socket) {
+  SetMinadbdSocketFd(-1);
+  ASSERT_EXIT(ExecuteCommandAndWaitForExit("sideload-host:4096:4096"),
+              ::testing::ExitedWithCode(kMinadbdSocketIOError), "");
+}
+
+TEST_F(MinadbdServicesTest, SideloadHostService_broken_recovery_socket) {
+  recovery_socket_.reset();
+  ASSERT_EXIT(ExecuteCommandAndWaitForExit("sideload-host:4096:4096"),
+              ::testing::ExitedWithCode(kMinadbdSocketIOError), "");
+}
+
+TEST_F(MinadbdServicesTest, SideloadHostService_wrong_command_format) {
+  auto test_body = [&](const std::string& command) {
+    unique_fd fd = daemon_service_to_fd(command, nullptr);
+    ASSERT_NE(-1, fd);
+    WaitForFusePath();
+    ReadAndCheckCommandMessage(recovery_socket_, MinadbdCommands::kInstall);
+
+    struct stat sb;
+    ASSERT_EQ(0, stat(exit_flag_.c_str(), &sb));
+    ASSERT_TRUE(android::base::WriteStringToFd("12345678", recovery_socket_));
+    sleep(EXIT_TIME_OUT);
+  };
+
+  ASSERT_EXIT(test_body("sideload-host:4096:4096"),
+              ::testing::ExitedWithCode(kMinadbdMessageFormatError), "");
+}
+
+TEST_F(MinadbdServicesTest, SideloadHostService_read_data_from_fuse) {
+  auto test_body = [&]() {
+    std::vector<uint8_t> content(4096, 'a');
+    // Start a new process instead of a thread to read from the package mounted by FUSE. Because
+    // the test may not exit and report failures correctly when the thread blocks by a syscall.
+    pid_t pid = fork();
+    if (pid == 0) {
+      WaitForFusePath();
+      android::base::unique_fd fd(TEMP_FAILURE_RETRY(open(package_path_.c_str(), O_RDONLY)));
+      // Do not use assertion here because we want to stat the exit flag and exit the process.
+      // Otherwise the test will wait for the time out instead of failing immediately.
+      if (fd == -1) {
+        PLOG(ERROR) << "Failed to open " << package_path_;
+        StatExitFlagAndExitProcess(1);
+      }
+      std::vector<uint8_t> content_from_fuse(4096);
+      if (!android::base::ReadFully(fd, content_from_fuse.data(), 4096)) {
+        PLOG(ERROR) << "Failed to read from " << package_path_;
+        StatExitFlagAndExitProcess(1);
+      }
+      if (content_from_fuse != content) {
+        LOG(ERROR) << "Content read from fuse doesn't match with the expected value";
+        StatExitFlagAndExitProcess(1);
+      }
+      StatExitFlagAndExitProcess(0);
+    }
+
+    unique_fd fd = daemon_service_to_fd("sideload-host:4096:4096", nullptr);
+    ASSERT_NE(-1, fd);
+    ReadAndCheckCommandMessage(recovery_socket_, MinadbdCommands::kInstall);
+
+    // Mimic the response from adb host.
+    std::string adb_message(8, '\0');
+    ASSERT_TRUE(android::base::ReadFully(fd, adb_message.data(), 8));
+    ASSERT_EQ(android::base::StringPrintf("%08u", 0), adb_message);
+    ASSERT_TRUE(android::base::WriteFully(fd, content.data(), 4096));
+
+    // Check that we read the correct data from fuse.
+    int child_status;
+    waitpid(pid, &child_status, 0);
+    ASSERT_TRUE(WIFEXITED(child_status));
+    ASSERT_EQ(0, WEXITSTATUS(child_status));
+
+    WriteMinadbdCommandStatus(MinadbdCommandStatus::kSuccess);
+
+    // TODO(xunchang) check if adb host-side receives "DONEDONE", there's a race condition between
+    // receiving the message and exit of test body (by detached thread in minadbd service).
+    exit(kMinadbdSuccess);
+  };
+
+  ASSERT_EXIT(test_body(), ::testing::ExitedWithCode(kMinadbdSuccess), "");
+}