1 // 2 // Copyright (C) 2012 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 #ifndef SHILL_ARP_CLIENT_H_ 18 #define SHILL_ARP_CLIENT_H_ 19 20 #include <memory> 21 22 #include <base/macros.h> 23 24 namespace shill { 25 26 class ArpPacket; 27 class ByteString; 28 class Sockets; 29 class ScopedSocketCloser; 30 31 // ArpClient task of creating ARP-capable sockets, as well as 32 // transmitting requests on and receiving responses from such 33 // sockets. 34 class ArpClient { 35 public: 36 explicit ArpClient(int interface_index); 37 virtual ~ArpClient(); 38 39 // Create a socket for reception of ARP replies, and packet trasmission. 40 // Returns true if successful, false otherwise. 41 virtual bool StartReplyListener(); 42 43 // Create a socket for reception of ARP requests, and packet trasmission. 44 // Returns true if successful, false otherwise. 45 virtual bool StartRequestListener(); 46 47 // Destroy the client socket. 48 virtual void Stop(); 49 50 // Receive an ARP request or reply and parse its contents into |packet|. 51 // Also return the sender's MAC address (which may be different from the 52 // MAC address in the ARP response) in |sender|. Returns true on 53 // succes, false otherwise. 54 virtual bool ReceivePacket(ArpPacket* packet, ByteString* sender) const; 55 56 // Send a formatted ARP request from |packet|. Returns true on 57 // success, false otherwise. 58 virtual bool TransmitRequest(const ArpPacket& packet) const; 59 60 virtual int socket() const { return socket_; } 61 62 bool IsStarted() { return socket_closer_.get(); } 63 64 private: 65 friend class ArpClientTest; 66 67 // Offset of the ARP OpCode within a captured ARP packet. 68 static const size_t kArpOpOffset; 69 70 // The largest packet we expect to receive as an ARP client. 71 static const size_t kMaxArpPacketLength; 72 73 // Start an ARP listener that listens for |arp_opcode| ARP packets. 74 bool Start(uint16_t arp_opcode); 75 bool CreateSocket(uint16_t arp_opcode); 76 77 const int interface_index_; 78 std::unique_ptr<Sockets> sockets_; 79 std::unique_ptr<ScopedSocketCloser> socket_closer_; 80 int socket_; 81 82 DISALLOW_COPY_AND_ASSIGN(ArpClient); 83 }; 84 85 } // namespace shill 86 87 #endif // SHILL_ARP_CLIENT_H_ 88
