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 <errno.h>
18 #include <stdio.h>
19 #include <string.h>
20
21 #include <sys/select.h>
22 #include <sys/socket.h>
23 #include <sys/time.h>
24 #include <sys/types.h>
25 #include <sys/un.h>
26
27 #include <linux/netlink.h>
28
29 #include <android-base/logging.h>
30
31 #include "NetlinkHandler.h"
32 #include "NetlinkManager.h"
33
34 NetlinkManager* NetlinkManager::sInstance = NULL;
35
Instance()36 NetlinkManager* NetlinkManager::Instance() {
37 if (!sInstance) sInstance = new NetlinkManager();
38 return sInstance;
39 }
40
NetlinkManager()41 NetlinkManager::NetlinkManager() {
42 mBroadcaster = NULL;
43 }
44
~NetlinkManager()45 NetlinkManager::~NetlinkManager() {}
46
start()47 int NetlinkManager::start() {
48 struct sockaddr_nl nladdr;
49 int sz = 64 * 1024;
50 int on = 1;
51
52 memset(&nladdr, 0, sizeof(nladdr));
53 nladdr.nl_family = AF_NETLINK;
54 nladdr.nl_pid = getpid();
55 nladdr.nl_groups = 0xffffffff;
56
57 if ((mSock = socket(PF_NETLINK, SOCK_DGRAM | SOCK_CLOEXEC, NETLINK_KOBJECT_UEVENT)) < 0) {
58 PLOG(ERROR) << "Unable to create uevent socket";
59 return -1;
60 }
61
62 // When running in a net/user namespace, SO_RCVBUFFORCE will fail because
63 // it will check for the CAP_NET_ADMIN capability in the root namespace.
64 // Try using SO_RCVBUF if that fails.
65 if ((setsockopt(mSock, SOL_SOCKET, SO_RCVBUFFORCE, &sz, sizeof(sz)) < 0) &&
66 (setsockopt(mSock, SOL_SOCKET, SO_RCVBUF, &sz, sizeof(sz)) < 0)) {
67 PLOG(ERROR) << "Unable to set uevent socket SO_RCVBUF/SO_RCVBUFFORCE option";
68 goto out;
69 }
70
71 if (setsockopt(mSock, SOL_SOCKET, SO_PASSCRED, &on, sizeof(on)) < 0) {
72 PLOG(ERROR) << "Unable to set uevent socket SO_PASSCRED option";
73 goto out;
74 }
75
76 if (bind(mSock, (struct sockaddr*)&nladdr, sizeof(nladdr)) < 0) {
77 PLOG(ERROR) << "Unable to bind uevent socket";
78 goto out;
79 }
80
81 mHandler = new NetlinkHandler(mSock);
82 if (mHandler->start()) {
83 PLOG(ERROR) << "Unable to start NetlinkHandler";
84 goto out;
85 }
86
87 return 0;
88
89 out:
90 close(mSock);
91 return -1;
92 }
93