1 /*
2  * Copyright (C) 2020 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 <android-base/logging.h>
18 #include <android-base/properties.h>
19 #include <android-base/strings.h>
20 #include <android-base/unique_fd.h>
21 #include <arpa/inet.h>
22 #include <ifaddrs.h>
23 #include <linux/if.h>
24 #include <string.h>
25 #include <sys/ioctl.h>
26 #include <sys/socket.h>
27 #include <sys/types.h>
28 
29 #include "recovery_ui/device.h"
30 #include "recovery_ui/ethernet_ui.h"
31 
32 class EthernetDevice : public Device {
33  public:
34   explicit EthernetDevice(EthernetRecoveryUI* ui);
35 
36   void PreRecovery() override;
37   void PreFastboot() override;
38 
39  private:
40   int SetInterfaceFlags(const unsigned set, const unsigned clr);
41   void SetTitleIPv6LinkLocalAddress(const bool interface_up);
42 
43   android::base::unique_fd ctl_sock_;
44   static const std::string interface;
45 };
46 
47 const std::string EthernetDevice::interface = "eth0";
48 
EthernetDevice(EthernetRecoveryUI * ui)49 EthernetDevice::EthernetDevice(EthernetRecoveryUI* ui)
50     : Device(ui), ctl_sock_(socket(AF_INET, SOCK_STREAM | SOCK_CLOEXEC, 0)) {
51   if (ctl_sock_ < 0) {
52     PLOG(ERROR) << "Failed to open socket";
53   }
54 }
55 
PreRecovery()56 void EthernetDevice::PreRecovery() {
57   SetInterfaceFlags(0, IFF_UP);
58   SetTitleIPv6LinkLocalAddress(false);
59 }
60 
PreFastboot()61 void EthernetDevice::PreFastboot() {
62   android::base::SetProperty("fastbootd.protocol", "tcp");
63 
64   if (SetInterfaceFlags(IFF_UP, 0) < 0) {
65     LOG(ERROR) << "Failed to bring up interface";
66     return;
67   }
68 
69   SetTitleIPv6LinkLocalAddress(true);
70 }
71 
SetInterfaceFlags(const unsigned set,const unsigned clr)72 int EthernetDevice::SetInterfaceFlags(const unsigned set, const unsigned clr) {
73   struct ifreq ifr;
74 
75   if (ctl_sock_ < 0) {
76     return -1;
77   }
78 
79   memset(&ifr, 0, sizeof(struct ifreq));
80   strncpy(ifr.ifr_name, interface.c_str(), IFNAMSIZ);
81   ifr.ifr_name[IFNAMSIZ - 1] = 0;
82 
83   if (ioctl(ctl_sock_, SIOCGIFFLAGS, &ifr) < 0) {
84     PLOG(ERROR) << "Failed to get interface active flags";
85     return -1;
86   }
87   ifr.ifr_flags = (ifr.ifr_flags & (~clr)) | set;
88 
89   if (ioctl(ctl_sock_, SIOCSIFFLAGS, &ifr) < 0) {
90     PLOG(ERROR) << "Failed to set interface active flags";
91     return -1;
92   }
93 
94   return 0;
95 }
96 
SetTitleIPv6LinkLocalAddress(const bool interface_up)97 void EthernetDevice::SetTitleIPv6LinkLocalAddress(const bool interface_up) {
98   auto recovery_ui = reinterpret_cast<EthernetRecoveryUI*>(GetUI());
99   if (!interface_up) {
100     recovery_ui->SetIPv6LinkLocalAddress();
101     return;
102   }
103 
104   struct ifaddrs* ifaddr;
105   if (getifaddrs(&ifaddr) == -1) {
106     PLOG(ERROR) << "Failed to get interface addresses";
107     recovery_ui->SetIPv6LinkLocalAddress();
108     return;
109   }
110 
111   std::unique_ptr<struct ifaddrs, decltype(&freeifaddrs)> guard{ ifaddr, freeifaddrs };
112   for (struct ifaddrs* ifa = ifaddr; ifa != nullptr; ifa = ifa->ifa_next) {
113     if (ifa->ifa_addr->sa_family != AF_INET6 || interface != ifa->ifa_name) {
114       continue;
115     }
116 
117     auto current_addr = reinterpret_cast<struct sockaddr_in6*>(ifa->ifa_addr);
118     if (!IN6_IS_ADDR_LINKLOCAL(&(current_addr->sin6_addr))) {
119       continue;
120     }
121 
122     char addrstr[INET6_ADDRSTRLEN];
123     inet_ntop(AF_INET6, reinterpret_cast<const void*>(&current_addr->sin6_addr), addrstr,
124               INET6_ADDRSTRLEN);
125     LOG(INFO) << "Our IPv6 link-local address is " << addrstr;
126     recovery_ui->SetIPv6LinkLocalAddress(addrstr);
127     return;
128   }
129 
130   recovery_ui->SetIPv6LinkLocalAddress();
131 }
132 
133 // -----------------------------------------------------------------------------------------
make_device()134 Device* make_device() {
135   return new EthernetDevice(new EthernetRecoveryUI);
136 }
137