1/*
2 * Copyright (C) 2008 The Android Open Source Project
3 *
4 * Licensed under the Apache License, Version 2.0 (the "License");
5 * you may not use this file except in compliance with the License.
6 * You may obtain a copy of the License at
7 *
8 *      http://www.apache.org/licenses/LICENSE-2.0
9 *
10 * Unless required by applicable law or agreed to in writing, software
11 * distributed under the License is distributed on an "AS IS" BASIS,
12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13 * See the License for the specific language governing permissions and
14 * limitations under the License.
15 */
16
17#include <stdio.h>
18#include <stdlib.h>
19#include <signal.h>
20#include <errno.h>
21#include <string.h>
22#include <sys/stat.h>
23#include <sys/types.h>
24#include <sys/wait.h>
25
26#include <fcntl.h>
27#include <dirent.h>
28
29#define LOG_TAG "Netd"
30
31#include "cutils/log.h"
32#include "utils/RWLock.h"
33
34#include <binder/IPCThreadState.h>
35#include <binder/IServiceManager.h>
36#include <binder/ProcessState.h>
37
38#include "CommandListener.h"
39#include "Controllers.h"
40#include "DnsProxyListener.h"
41#include "FwmarkServer.h"
42#include "MDnsSdListener.h"
43#include "NFLogListener.h"
44#include "NetdConstants.h"
45#include "NetdHwService.h"
46#include "NetdNativeService.h"
47#include "NetlinkManager.h"
48#include "Stopwatch.h"
49
50using android::status_t;
51using android::sp;
52using android::IPCThreadState;
53using android::ProcessState;
54using android::defaultServiceManager;
55using android::net::CommandListener;
56using android::net::DnsProxyListener;
57using android::net::FwmarkServer;
58using android::net::NetdHwService;
59using android::net::NetdNativeService;
60using android::net::NetlinkManager;
61using android::net::NFLogListener;
62using android::net::makeNFLogListener;
63
64static void remove_pid_file();
65static bool write_pid_file();
66
67const char* const PID_FILE_PATH = "/data/misc/net/netd_pid";
68const int PID_FILE_FLAGS = O_CREAT | O_TRUNC | O_WRONLY | O_NOFOLLOW | O_CLOEXEC;
69const mode_t PID_FILE_MODE = S_IRUSR | S_IWUSR | S_IRGRP | S_IROTH;  // mode 0644, rw-r--r--
70
71android::RWLock android::net::gBigNetdLock;
72
73int main() {
74    using android::net::gCtls;
75    Stopwatch s;
76
77    ALOGI("Netd 1.0 starting");
78    remove_pid_file();
79
80    blockSigpipe();
81
82    // Before we do anything that could fork, mark CLOEXEC the UNIX sockets that we get from init.
83    // FrameworkListener does this on initialization as well, but we only initialize these
84    // components after having initialized other subsystems that can fork.
85    for (const auto& sock : { CommandListener::SOCKET_NAME,
86                              DnsProxyListener::SOCKET_NAME,
87                              FwmarkServer::SOCKET_NAME,
88                              MDnsSdListener::SOCKET_NAME }) {
89        setCloseOnExec(sock);
90    }
91
92    NetlinkManager *nm = NetlinkManager::Instance();
93    if (nm == nullptr) {
94        ALOGE("Unable to create NetlinkManager");
95        exit(1);
96    };
97
98    gCtls = new android::net::Controllers();
99    gCtls->init();
100
101    CommandListener cl;
102    nm->setBroadcaster((SocketListener *) &cl);
103
104    if (nm->start()) {
105        ALOGE("Unable to start NetlinkManager (%s)", strerror(errno));
106        exit(1);
107    }
108
109    std::unique_ptr<NFLogListener> logListener;
110    {
111        auto result = makeNFLogListener();
112        if (!isOk(result)) {
113            ALOGE("Unable to create NFLogListener: %s", toString(result).c_str());
114            exit(1);
115        }
116        logListener = std::move(result.value());
117        auto status = gCtls->wakeupCtrl.init(logListener.get());
118        if (!isOk(result)) {
119            ALOGE("Unable to init WakeupController: %s", toString(result).c_str());
120            // We can still continue without wakeup packet logging.
121        }
122    }
123
124    // Set local DNS mode, to prevent bionic from proxying
125    // back to this service, recursively.
126    setenv("ANDROID_DNS_MODE", "local", 1);
127    DnsProxyListener dpl(&gCtls->netCtrl, &gCtls->eventReporter);
128    if (dpl.startListener()) {
129        ALOGE("Unable to start DnsProxyListener (%s)", strerror(errno));
130        exit(1);
131    }
132
133    MDnsSdListener mdnsl;
134    if (mdnsl.startListener()) {
135        ALOGE("Unable to start MDnsSdListener (%s)", strerror(errno));
136        exit(1);
137    }
138
139    FwmarkServer fwmarkServer(&gCtls->netCtrl, &gCtls->eventReporter, &gCtls->trafficCtrl);
140    if (fwmarkServer.startListener()) {
141        ALOGE("Unable to start FwmarkServer (%s)", strerror(errno));
142        exit(1);
143    }
144
145    Stopwatch subTime;
146    status_t ret;
147    if ((ret = NetdNativeService::start()) != android::OK) {
148        ALOGE("Unable to start NetdNativeService: %d", ret);
149        exit(1);
150    }
151    ALOGI("Registering NetdNativeService: %.1fms", subTime.getTimeAndReset());
152
153    /*
154     * Now that we're up, we can respond to commands. Starting the listener also tells
155     * NetworkManagementService that we are up and that our binder interface is ready.
156     */
157    if (cl.startListener()) {
158        ALOGE("Unable to start CommandListener (%s)", strerror(errno));
159        exit(1);
160    }
161    ALOGI("Starting CommandListener: %.1fms", subTime.getTimeAndReset());
162
163    write_pid_file();
164
165    // Now that netd is ready to process commands, advertise service
166    // availability for HAL clients.
167    NetdHwService mHwSvc;
168    if ((ret = mHwSvc.start()) != android::OK) {
169        ALOGE("Unable to start NetdHwService: %d", ret);
170        exit(1);
171    }
172    ALOGI("Registering NetdHwService: %.1fms", subTime.getTimeAndReset());
173
174    ALOGI("Netd started in %dms", static_cast<int>(s.timeTaken()));
175
176    IPCThreadState::self()->joinThreadPool();
177
178    ALOGI("Netd exiting");
179
180    remove_pid_file();
181
182    exit(0);
183}
184
185static bool write_pid_file() {
186    char pid_buf[INT32_STRLEN];
187    snprintf(pid_buf, sizeof(pid_buf), "%d\n", (int) getpid());
188
189    int fd = open(PID_FILE_PATH, PID_FILE_FLAGS, PID_FILE_MODE);
190    if (fd == -1) {
191        ALOGE("Unable to create pid file (%s)", strerror(errno));
192        return false;
193    }
194
195    // File creation is affected by umask, so make sure the right mode bits are set.
196    if (fchmod(fd, PID_FILE_MODE) == -1) {
197        ALOGE("failed to set mode 0%o on %s (%s)", PID_FILE_MODE, PID_FILE_PATH, strerror(errno));
198        close(fd);
199        remove_pid_file();
200        return false;
201    }
202
203    if (write(fd, pid_buf, strlen(pid_buf)) != (ssize_t)strlen(pid_buf)) {
204        ALOGE("Unable to write to pid file (%s)", strerror(errno));
205        close(fd);
206        remove_pid_file();
207        return false;
208    }
209    close(fd);
210    return true;
211}
212
213static void remove_pid_file() {
214    unlink(PID_FILE_PATH);
215}
216