Determine connection type in NetworkChangeNotifierLinux.

net/base/net_util_linux.cc

 // Copyright (c) 2014 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "net/base/net_util_linux.h"
 
-#include <net/if.h>
-#include <netinet/in.h>
+#include <linux/if.h>
+#include <linux/wireless.h>
 #include <set>
+#include <sys/ioctl.h>
 #include <sys/types.h>
 
 #include "base/files/file_path.h"
 #include "base/logging.h"
 #include "base/memory/scoped_ptr.h"
 #include "base/strings/string_number_conversions.h"
 #include "base/strings/string_tokenizer.h"
 #include "base/strings/string_util.h"
 #include "base/threading/thread_restrictions.h"
 #include "net/base/address_tracker_linux.h"
@@ skipping 42 matching lines @@
 namespace internal {
 
 inline const unsigned char* GetIPAddressData(const IPAddressNumber& ip) {
 #if defined(OS_ANDROID)
   return ip.begin();
 #else
   return ip.data();
 #endif
 }
 
+// Gets the connection type for interface |ifname| by checking for wireless
+// extensions.
+NetworkChangeNotifier::ConnectionType GetInterfaceConnectionType(
+    const std::string& ifname) {
+  NetworkChangeNotifier::ConnectionType type =
+      NetworkChangeNotifier::CONNECTION_UNKNOWN;
+
+  int s = socket(AF_INET, SOCK_STREAM, 0);
+  if (s == -1)
+    return type;
+
+  struct iwreq pwrq;
+  memset(&pwrq, 0, sizeof(pwrq));
+  strncpy(pwrq.ifr_name, ifname.c_str(), IFNAMSIZ);
+
+  if (ioctl(s, SIOCGIWNAME, &pwrq) != -1)
+    type = NetworkChangeNotifier::CONNECTION_WIFI;
+

[pauljensen, 2015/01/28 00:27:53]

Could we use SIOCETHTOOL to identify ethernet devices? "ethtool" seems to be
able to differentiate eth0 and wlan0 appropriately.  "strace ethtool" shows it
using SIOCETHTOOL.

[derekjchow1, 2015/01/28 18:12:48]

Nice. Done.

I tested SIOCETHTOOL last night on my laptop and a small computer with USB wifi.
Seems to work to distinguish ethernet.

See this demo I used to test:
https://gist.github.com/anonymous/7bb9dbb089924f3800f7

+  close(s);
+  return type;
+}
+
 bool GetNetworkListImpl(
     NetworkInterfaceList* networks,
     int policy,
     const base::hash_set<int>& online_links,
     const internal::AddressTrackerLinux::AddressMap& address_map,
     GetInterfaceNameFunction get_interface_name) {
   std::map<int, std::string> ifnames;
 
   for (internal::AddressTrackerLinux::AddressMap::const_iterator it =
            address_map.begin();
@@ skipping 23 matching lines @@
       if (!TryConvertNativeToNetIPAttributes(it->second.ifa_flags,
                                              &ip_attributes))
         continue;
     }
 
     // Find the name of this link.
     std::map<int, std::string>::const_iterator itname =
         ifnames.find(it->second.ifa_index);
     std::string ifname;
     if (itname == ifnames.end()) {
-      char buffer[IF_NAMESIZE] = {0};
+      char buffer[IFNAMSIZ] = {0};
       if (get_interface_name(it->second.ifa_index, buffer)) {
         ifname = ifnames[it->second.ifa_index] = buffer;
       } else {
         // Ignore addresses whose interface name can't be retrieved.
         continue;
       }
     } else {
       ifname = itname->second;
     }
 
     // Based on the interface name and policy, determine whether we
     // should ignore it.
     if (ShouldIgnoreInterface(ifname, policy))
       continue;
 
+    NetworkChangeNotifier::ConnectionType type =
+        GetInterfaceConnectionType(ifname);
+
     networks->push_back(
-        NetworkInterface(ifname, ifname, it->second.ifa_index,
-                         NetworkChangeNotifier::CONNECTION_UNKNOWN, it->first,
+        NetworkInterface(ifname, ifname, it->second.ifa_index, type, it->first,
                          it->second.ifa_prefixlen, ip_attributes));
   }
 
   return true;
 }
 
 }  // namespace internal
 
 bool GetNetworkList(NetworkInterfaceList* networks, int policy) {
   if (networks == NULL)
     return false;
 
   internal::AddressTrackerLinux tracker;
   tracker.Init();
 
-  return internal::GetNetworkListImpl(networks, policy,
-                                      tracker.GetOnlineLinks(),
-                                      tracker.GetAddressMap(), &if_indextoname);
+  return internal::GetNetworkListImpl(
+      networks, policy, tracker.GetOnlineLinks(), tracker.GetAddressMap(),
+      &internal::AddressTrackerLinux::GetInterfaceName);
 }
 
 }  // namespace net