1//
2// Copyright (C) 2015 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 "dhcp_client/device_info.h"
18
19#include <net/if.h>
20#include <netinet/in.h>
21#include <sys/ioctl.h>
22
23#include <memory>
24#include <string>
25
26#include <base/logging.h>
27
28using shill::ByteString;
29using shill::Sockets;
30using shill::RTNLHandler;
31using std::unique_ptr;
32
33namespace {
34
35base::LazyInstance<dhcp_client::DeviceInfo> g_dhcp_device_info
36    = LAZY_INSTANCE_INITIALIZER;
37
38}  // namespace
39
40namespace dhcp_client {
41
42DeviceInfo::DeviceInfo()
43    : sockets_(new Sockets()),
44      rtnl_handler_(RTNLHandler::GetInstance()) {
45}
46
47DeviceInfo::~DeviceInfo() {}
48
49DeviceInfo* DeviceInfo::GetInstance() {
50  return g_dhcp_device_info.Pointer();
51}
52
53bool DeviceInfo::GetDeviceInfo(const std::string& interface_name,
54                               ByteString* mac_address,
55                               unsigned int* interface_index ) {
56  struct ifreq ifr;
57  size_t if_name_len = interface_name.size();
58  if (if_name_len > IFNAMSIZ) {
59    LOG(ERROR) << "Interface name is too long.";
60    return false;
61  }
62  memcpy(ifr.ifr_name, interface_name.c_str(), if_name_len);
63  ifr.ifr_name[if_name_len] = 0;
64  int fd = sockets_->Socket(AF_INET, SOCK_DGRAM, 0);
65  if (fd == -1) {
66    PLOG(ERROR) << "Failed to create socket.";
67    return false;
68  }
69
70  shill::ScopedSocketCloser socket_closer(sockets_.get(), fd);
71  // Get interface hardware address
72  if (sockets_->Ioctl(fd, SIOCGIFHWADDR, &ifr) == -1) {
73    PLOG(ERROR) << "Failed to get interface hardware address.";
74    return false;
75  }
76  int if_index = rtnl_handler_->GetInterfaceIndex(interface_name);
77  if (if_index == -1) {
78    LOG(ERROR) << "Unable to get interface index.";
79    return false;
80  }
81  *interface_index = if_index;
82  *mac_address = ByteString(ifr.ifr_hwaddr.sa_data, IFHWADDRLEN);
83
84  return true;
85}
86
87}  // namespace dhcp_client
88
89