1 //
2 // Copyright (C) 2014 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 "update_engine/update_manager/real_shill_provider.h"
18 
19 #include <string>
20 
21 #include <base/logging.h>
22 #include <base/strings/stringprintf.h>
23 #include <brillo/type_name_undecorate.h>
24 #include <shill/dbus-constants.h>
25 #include <shill/dbus-proxies.h>
26 
27 using chromeos_update_engine::connection_utils::ParseConnectionType;
28 using org::chromium::flimflam::ManagerProxyInterface;
29 using org::chromium::flimflam::ServiceProxyInterface;
30 using std::string;
31 
32 namespace chromeos_update_manager {
33 
34 bool RealShillProvider::Init() {
35   ManagerProxyInterface* manager_proxy = shill_proxy_->GetManagerProxy();
36   if (!manager_proxy)
37     return false;
38 
39   // Subscribe to the manager's PropertyChanged signal.
40   manager_proxy->RegisterPropertyChangedSignalHandler(
41       base::Bind(&RealShillProvider::OnManagerPropertyChanged,
42                  base::Unretained(this)),
43       base::Bind(&RealShillProvider::OnSignalConnected,
44                  base::Unretained(this)));
45 
46   // Attempt to read initial connection status. Even if this fails because shill
47   // is not responding (e.g. it is down) we'll be notified via "PropertyChanged"
48   // signal as soon as it comes up, so this is not a critical step.
49   brillo::VariantDictionary properties;
50   brillo::ErrorPtr error;
51   if (!manager_proxy->GetProperties(&properties, &error))
52     return true;
53 
54   const auto& prop_default_service =
55       properties.find(shill::kDefaultServiceProperty);
56   if (prop_default_service != properties.end()) {
57     OnManagerPropertyChanged(prop_default_service->first,
58                              prop_default_service->second);
59   }
60 
61   return true;
62 }
63 
64 void RealShillProvider::OnManagerPropertyChanged(const string& name,
65                                                  const brillo::Any& value) {
66   if (name == shill::kDefaultServiceProperty) {
67     dbus::ObjectPath service_path = value.TryGet<dbus::ObjectPath>();
68     if (!service_path.IsValid()) {
69       LOG(WARNING) << "Got an invalid DefaultService path. The property value "
70                       "contains a "
71                    << value.GetUndecoratedTypeName()
72                    << ", read as the object path: '" << service_path.value()
73                    << "'";
74     }
75     ProcessDefaultService(service_path);
76   }
77 }
78 
79 void RealShillProvider::OnSignalConnected(const string& interface_name,
80                                           const string& signal_name,
81                                           bool successful) {
82   if (!successful) {
83     LOG(ERROR) << "Couldn't connect to the signal " << interface_name << "."
84                << signal_name;
85   }
86 }
87 
88 bool RealShillProvider::ProcessDefaultService(
89     const dbus::ObjectPath& default_service_path) {
90   // We assume that if the service path didn't change, then the connection
91   // type and the tethering status of it also didn't change.
92   if (default_service_path_ == default_service_path)
93     return true;
94 
95   // Update the connection status.
96   default_service_path_ = default_service_path;
97   bool is_connected =
98       (default_service_path_.IsValid() && default_service_path_.value() != "/");
99   var_is_connected_.SetValue(is_connected);
100   var_conn_last_changed_.SetValue(clock_->GetWallclockTime());
101 
102   if (!is_connected) {
103     var_conn_type_.UnsetValue();
104     var_conn_tethering_.UnsetValue();
105     return true;
106   }
107 
108   // We create and dispose the ServiceProxyInterface on every request.
109   std::unique_ptr<ServiceProxyInterface> service =
110       shill_proxy_->GetServiceForPath(default_service_path_);
111 
112   // Get the connection properties synchronously.
113   brillo::VariantDictionary properties;
114   brillo::ErrorPtr error;
115   if (!service->GetProperties(&properties, &error)) {
116     var_conn_type_.UnsetValue();
117     var_conn_tethering_.UnsetValue();
118     return false;
119   }
120 
121   // Get the connection tethering mode.
122   const auto& prop_tethering = properties.find(shill::kTetheringProperty);
123   if (prop_tethering == properties.end()) {
124     // Remove the value if not present on the service. This most likely means an
125     // error in shill and the policy will handle it, but we will print a log
126     // message as well for accessing an unused variable.
127     var_conn_tethering_.UnsetValue();
128     LOG(ERROR) << "Could not find connection type (service: "
129                << default_service_path_.value() << ")";
130   } else {
131     // If the property doesn't contain a string value, the empty string will
132     // become kUnknown.
133     var_conn_tethering_.SetValue(
134         chromeos_update_engine::connection_utils::ParseConnectionTethering(
135             prop_tethering->second.TryGet<string>()));
136   }
137 
138   // Get the connection type.
139   const auto& prop_type = properties.find(shill::kTypeProperty);
140   if (prop_type == properties.end()) {
141     var_conn_type_.UnsetValue();
142     LOG(ERROR) << "Could not find connection tethering mode (service: "
143                << default_service_path_.value() << ")";
144   } else {
145     string type_str = prop_type->second.TryGet<string>();
146     if (type_str == shill::kTypeVPN) {
147       const auto& prop_physical =
148           properties.find(shill::kPhysicalTechnologyProperty);
149       if (prop_physical == properties.end()) {
150         LOG(ERROR) << "No PhysicalTechnology property found for a VPN"
151                    << " connection (service: " << default_service_path_.value()
152                    << "). Using default kUnknown value.";
153         var_conn_type_.SetValue(
154             chromeos_update_engine::ConnectionType::kUnknown);
155       } else {
156         var_conn_type_.SetValue(
157             ParseConnectionType(prop_physical->second.TryGet<string>()));
158       }
159     } else {
160       var_conn_type_.SetValue(ParseConnectionType(type_str));
161     }
162   }
163 
164   return true;
165 }
166 
167 }  // namespace chromeos_update_manager
168