Implement chrome.sockets.udp.setBroadcast.

Enable Chrome Apps to receive broadcast UDP traffic by setting the
SO_BROADCAST option on a socket. This feature piggybacks on existing
permissions as it requires a socket to be bound to the interface where
the broadcast traffic will be received.

BUG=308461

Review URL: https://codereview.chromium.org/1071813002

Cr-Commit-Position: refs/heads/master@{#324768}

8 files changed, 158 insertions, 1 deletions

diff --git a/extensions/browser/api/socket/udp_socket.cc b/extensions/browser/api/socket/udp_socket.cc
index 42d7bc3..2822046 100644
--- a/extensions/browser/api/socket/udp_socket.cc
+++ b/extensions/browser/api/socket/udp_socket.cc
@@ -297,6 +297,13 @@ int UDPSocket::SetMulticastLoopbackMode(bool loopback) {
   return socket_.SetMulticastLoopbackMode(loopback);
 }
 
+int UDPSocket::SetBroadcast(bool enabled) {
+  if (!socket_.is_connected()) {
+    return net::ERR_SOCKET_NOT_CONNECTED;
+  }
+  return socket_.SetBroadcast(enabled);
+}
+
 const std::vector<std::string>& UDPSocket::GetJoinedGroups() const {
   return multicast_groups_;
 }
diff --git a/extensions/browser/api/socket/udp_socket.h b/extensions/browser/api/socket/udp_socket.h
index 3169960..9b63b2c 100644
--- a/extensions/browser/api/socket/udp_socket.h
+++ b/extensions/browser/api/socket/udp_socket.h
@@ -45,6 +45,8 @@ class UDPSocket : public Socket {
   int SetMulticastTimeToLive(int ttl);
   int SetMulticastLoopbackMode(bool loopback);
 
+  int SetBroadcast(bool enabled);
+
   const std::vector<std::string>& GetJoinedGroups() const;
 
  protected:
diff --git a/extensions/browser/api/sockets_udp/sockets_udp_api.cc b/extensions/browser/api/sockets_udp/sockets_udp_api.cc
index b269aa8..5cdcee6 100644
--- a/extensions/browser/api/sockets_udp/sockets_udp_api.cc
+++ b/extensions/browser/api/sockets_udp/sockets_udp_api.cc
@@ -506,5 +506,31 @@ void SocketsUdpGetJoinedGroupsFunction::Work() {
   results_ = sockets_udp::GetJoinedGroups::Results::Create(groups);
 }
 
+SocketsUdpSetBroadcastFunction::SocketsUdpSetBroadcastFunction() {
+}
+
+SocketsUdpSetBroadcastFunction::~SocketsUdpSetBroadcastFunction() {
+}
+
+bool SocketsUdpSetBroadcastFunction::Prepare() {
+  params_ = core_api::sockets_udp::SetBroadcast::Params::Create(*args_);
+  EXTENSION_FUNCTION_VALIDATE(params_.get());
+  return true;
+}
+
+void SocketsUdpSetBroadcastFunction::Work() {
+  ResumableUDPSocket* socket = GetUdpSocket(params_->socket_id);
+  if (!socket) {
+    error_ = kSocketNotFoundError;
+    return;
+  }
+
+  int net_result = socket->SetBroadcast(params_->enabled);
+  if (net_result != net::OK) {
+    error_ = net::ErrorToString(net_result);
+  }
+  results_ = sockets_udp::SetBroadcast::Results::Create(net_result);
+}
+
 }  // namespace core_api
 }  // namespace extensions
diff --git a/extensions/browser/api/sockets_udp/sockets_udp_api.h b/extensions/browser/api/sockets_udp/sockets_udp_api.h
index 20fd7e6..2df2dbc1 100644
--- a/extensions/browser/api/sockets_udp/sockets_udp_api.h
+++ b/extensions/browser/api/sockets_udp/sockets_udp_api.h
@@ -273,6 +273,24 @@ class SocketsUdpGetJoinedGroupsFunction : public UDPSocketAsyncApiFunction {
   scoped_ptr<sockets_udp::GetJoinedGroups::Params> params_;
 };
 
+class SocketsUdpSetBroadcastFunction : public UDPSocketAsyncApiFunction {
+ public:
+  DECLARE_EXTENSION_FUNCTION("sockets.udp.setBroadcast",
+                             SOCKETS_UDP_SETBROADCAST)
+
+  SocketsUdpSetBroadcastFunction();
+
+ protected:
+  ~SocketsUdpSetBroadcastFunction() override;
+
+  // AsyncApiFunction
+  bool Prepare() override;
+  void Work() override;
+
+ private:
+  scoped_ptr<sockets_udp::SetBroadcast::Params> params_;
+};
+
 }  // namespace core_api
 }  // namespace extensions
 
diff --git a/extensions/browser/extension_function_histogram_value.h b/extensions/browser/extension_function_histogram_value.h
index cdcdeb5..c182e48 100644
--- a/extensions/browser/extension_function_histogram_value.h
+++ b/extensions/browser/extension_function_histogram_value.h
@@ -1060,6 +1060,7 @@ enum HistogramValue {
   NETWORKINGPRIVATE_GETDEVICESTATES,
   DEVELOPERPRIVATE_GETPROFILECONFIGURATION,
   DEVELOPERPRIVATE_UPDATEPROFILECONFIGURATION,
+  SOCKETS_UDP_SETBROADCAST,
   // Last entry: Add new entries above and ensure to update
   // tools/metrics/histograms/histograms.xml.
   ENUM_BOUNDARY
diff --git a/extensions/common/api/sockets_udp.idl b/extensions/common/api/sockets_udp.idl
index 8ce5a23..784a31d 100644
--- a/extensions/common/api/sockets_udp.idl
+++ b/extensions/common/api/sockets_udp.idl
@@ -128,6 +128,10 @@ namespace sockets.udp {
   // |groups| : Array of groups the socket joined.
   callback GetJoinedGroupsCallback = void (DOMString[] groups);
 
+  // Callback from the <code>setBroadcast</code> method.
+  // |result| : The result code returned from the underlying network call.
+  callback SetBroadcastCallback = void (long result);
+
   // Data from an <code>onReceive</code> event.
   dictionary ReceiveInfo {
     // The socket ID.
@@ -291,6 +295,15 @@ namespace sockets.udp {
     // |callback| : Called with an array of strings of the result.
     static void getJoinedGroups(long socketId,
                                 GetJoinedGroupsCallback callback);
+
+    // Enables or disables broadcast packets on this socket.
+    //
+    // |socketId| : The socket ID.
+    // |enabled| : <code>true</code> to enable broadcast packets,
+    // <code>false</code> to disable them.
+    static void setBroadcast(long socketId,
+                             boolean enabled,
+                             SetBroadcastCallback callback);
   };
 
   interface Events {
diff --git a/extensions/test/data/sockets_udp/api/background.js b/extensions/test/data/sockets_udp/api/background.js
index 50dfff6..8382292 100644
--- a/extensions/test/data/sockets_udp/api/background.js
+++ b/extensions/test/data/sockets_udp/api/background.js
@@ -228,6 +228,94 @@ var testSetPaused = function() {
   }
 }
 
+var testBroadcast = function() {
+  var listeningSocketId;
+  var sendingSocketId;
+
+  console.log("testBroadcast");
+  chrome.sockets.udp.create({}, onCreate);
+
+  function onCreate(socketInfo) {
+    console.log("socket created: " + socketInfo.socketId);
+    chrome.test.assertTrue(socketId > 0, "failed to create socket");
+
+    if (listeningSocketId == undefined) {
+      listeningSocketId = socketInfo.socketId;
+      chrome.sockets.udp.onReceive.addListener(onReceive);
+      chrome.sockets.udp.onReceiveError.addListener(onReceiveError);
+      chrome.sockets.udp.bind(
+          listeningSocketId, "0.0.0.0", 8000, onBindListening);
+    } else {
+      sendingSocketId = socketInfo.socketId;
+      chrome.sockets.udp.bind(
+          sendingSocketId, "127.0.0.1", 8001, onBindSending);
+    }
+  }
+
+  function onBindListening(result) {
+    chrome.test.assertEq(0, result, "Bind failed with error: " + result);
+    if (result < 0) {
+      return;
+    }
+
+    chrome.sockets.udp.setBroadcast(
+        listeningSocketId, true, onSetBroadcastListening);
+  }
+
+  function onSetBroadcastListening(result) {
+    chrome.test.assertEq(0, result, "Failed to enable broadcast: " + result);
+    if (result < 0) {
+      return;
+    }
+
+    // Create the sending socket.
+    chrome.sockets.udp.create({}, onCreate);
+  }
+
+  function onBindSending(result) {
+    chrome.test.assertEq(0, result, "Bind failed with error: " + result);
+    if (result < 0) {
+      return;
+    }
+
+    chrome.sockets.udp.setBroadcast(
+        sendingSocketId, true, onSetBroadcastSending);
+  }
+
+  function onSetBroadcastSending(result) {
+    chrome.test.assertEq(0, result, "Failed to enable broadcast: " + result);
+    if (result < 0) {
+      return;
+    }
+
+    string2ArrayBuffer("broadcast packet", onArrayBuffer);
+  }
+
+  function onArrayBuffer(arrayBuffer) {
+    console.log("sending bytes to broadcast: " + arrayBuffer.byteLength);
+    chrome.sockets.udp.send(sendingSocketId, arrayBuffer, "127.255.255.255",
+                            8000, function(sendInfo) {
+      chrome.test.assertEq(0, sendInfo.resultCode);
+      chrome.test.assertEq(sendInfo.bytesSent, arrayBuffer.byteLength);
+    });
+  }
+
+  function onReceiveError(info) {
+    chrome.test.fail("Socket receive error: " + info.resultCode);
+  }
+
+  function onReceive(info) {
+    console.log("Received data on socket" + "(" + info.socketId + ")");
+    chrome.test.assertEq(listeningSocketId, info.socketId);
+    chrome.test.assertEq("127.0.0.1", info.remoteAddress);
+    chrome.test.assertEq(8001, info.remotePort);
+    arrayBuffer2String(info.data, function(string) {
+      chrome.test.assertEq("broadcast packet", string);
+      chrome.test.succeed();
+    });
+  }
+};
+
 ///////////////////////////////////////////////////////////////////////////////
 // Test driver
 //
@@ -244,7 +332,8 @@ var onMessageReply = function(message) {
     chrome.test.runTests([ testMulticast ]);
   } else {
     console.log("Running udp tests");
-    chrome.test.runTests([ testSocketCreation, testSending, testSetPaused ]);
+    chrome.test.runTests([ testSocketCreation, testSending, testSetPaused,
+                           testBroadcast ]);
   }
 };
 
diff --git a/tools/metrics/histograms/histograms.xml b/tools/metrics/histograms/histograms.xml
index 1f4e112..2d2ef79 100644
--- a/tools/metrics/histograms/histograms.xml
+++ b/tools/metrics/histograms/histograms.xml
@@ -50336,6 +50336,7 @@ Therefore, the affected-histogram name has to have at least one dot in it.
   <int value="999" label="NETWORKINGPRIVATE_GETDEVICESTATES"/>
   <int value="1000" label="DEVELOPERPRIVATE_GETPROFILECONFIGURATION"/>
   <int value="1001" label="DEVELOPERPRIVATE_UPDATEPROFILECONFIGURATION"/>
+  <int value="1002" label="SOCKETS_UDP_SETBROADCAST"/>
 </enum>
 
 <enum name="ExtensionInstallCause" type="int">