1 /* 2 * libjingle 3 * Copyright 2004--2005, Google Inc. 4 * 5 * Redistribution and use in source and binary forms, with or without 6 * modification, are permitted provided that the following conditions are met: 7 * 8 * 1. Redistributions of source code must retain the above copyright notice, 9 * this list of conditions and the following disclaimer. 10 * 2. Redistributions in binary form must reproduce the above copyright notice, 11 * this list of conditions and the following disclaimer in the documentation 12 * and/or other materials provided with the distribution. 13 * 3. The name of the author may not be used to endorse or promote products 14 * derived from this software without specific prior written permission. 15 * 16 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR IMPLIED 17 * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF 18 * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO 19 * EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, 20 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, 21 * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; 22 * OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, 23 * WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR 24 * OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF 25 * ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 26 */ 27 28 #ifndef TALK_P2P_BASE_TRANSPORTCHANNEL_H_ 29 #define TALK_P2P_BASE_TRANSPORTCHANNEL_H_ 30 31 #include <string> 32 #include <vector> 33 34 #include "talk/base/asyncpacketsocket.h" 35 #include "talk/base/basictypes.h" 36 #include "talk/base/dscp.h" 37 #include "talk/base/sigslot.h" 38 #include "talk/base/socket.h" 39 #include "talk/base/sslidentity.h" 40 #include "talk/base/sslstreamadapter.h" 41 #include "talk/p2p/base/candidate.h" 42 #include "talk/p2p/base/transport.h" 43 #include "talk/p2p/base/transportdescription.h" 44 45 namespace cricket { 46 47 class Candidate; 48 49 // Flags for SendPacket/SignalReadPacket. 50 enum PacketFlags { 51 PF_NORMAL = 0x00, // A normal packet. 52 PF_SRTP_BYPASS = 0x01, // An encrypted SRTP packet; bypass any additional 53 // crypto provided by the transport (e.g. DTLS) 54 }; 55 56 // A TransportChannel represents one logical stream of packets that are sent 57 // between the two sides of a session. 58 class TransportChannel : public sigslot::has_slots<> { 59 public: 60 explicit TransportChannel(const std::string& content_name, int component) 61 : content_name_(content_name), 62 component_(component), 63 readable_(false), writable_(false) {} 64 virtual ~TransportChannel() {} 65 66 // TODO(mallinath) - Remove this API, as it's no longer useful. 67 // Returns the session id of this channel. 68 virtual const std::string SessionId() const { return std::string(); } 69 70 const std::string& content_name() const { return content_name_; } 71 int component() const { return component_; } 72 73 // Returns the readable and states of this channel. Each time one of these 74 // states changes, a signal is raised. These states are aggregated by the 75 // TransportManager. 76 bool readable() const { return readable_; } 77 bool writable() const { return writable_; } 78 sigslot::signal1<TransportChannel*> SignalReadableState; 79 sigslot::signal1<TransportChannel*> SignalWritableState; 80 // Emitted when the TransportChannel's ability to send has changed. 81 sigslot::signal1<TransportChannel*> SignalReadyToSend; 82 83 // Attempts to send the given packet. The return value is < 0 on failure. 84 // TODO: Remove the default argument once channel code is updated. 85 virtual int SendPacket(const char* data, size_t len, 86 const talk_base::PacketOptions& options, 87 int flags = 0) = 0; 88 89 // Sets a socket option on this channel. Note that not all options are 90 // supported by all transport types. 91 virtual int SetOption(talk_base::Socket::Option opt, int value) = 0; 92 93 // Returns the most recent error that occurred on this channel. 94 virtual int GetError() = 0; 95 96 // Returns the current stats for this connection. 97 virtual bool GetStats(ConnectionInfos* infos) = 0; 98 99 // Is DTLS active? 100 virtual bool IsDtlsActive() const = 0; 101 102 // Default implementation. 103 virtual bool GetSslRole(talk_base::SSLRole* role) const = 0; 104 105 // Sets up the ciphers to use for DTLS-SRTP. 106 virtual bool SetSrtpCiphers(const std::vector<std::string>& ciphers) = 0; 107 108 // Finds out which DTLS-SRTP cipher was negotiated 109 virtual bool GetSrtpCipher(std::string* cipher) = 0; 110 111 // Gets a copy of the local SSL identity, owned by the caller. 112 virtual bool GetLocalIdentity(talk_base::SSLIdentity** identity) const = 0; 113 114 // Gets a copy of the remote side's SSL certificate, owned by the caller. 115 virtual bool GetRemoteCertificate(talk_base::SSLCertificate** cert) const = 0; 116 117 // Allows key material to be extracted for external encryption. 118 virtual bool ExportKeyingMaterial(const std::string& label, 119 const uint8* context, 120 size_t context_len, 121 bool use_context, 122 uint8* result, 123 size_t result_len) = 0; 124 125 // Signalled each time a packet is received on this channel. 126 sigslot::signal5<TransportChannel*, const char*, 127 size_t, const talk_base::PacketTime&, int> SignalReadPacket; 128 129 // This signal occurs when there is a change in the way that packets are 130 // being routed, i.e. to a different remote location. The candidate 131 // indicates where and how we are currently sending media. 132 sigslot::signal2<TransportChannel*, const Candidate&> SignalRouteChange; 133 134 // Invoked when the channel is being destroyed. 135 sigslot::signal1<TransportChannel*> SignalDestroyed; 136 137 // Debugging description of this transport channel. 138 std::string ToString() const; 139 140 protected: 141 // Sets the readable state, signaling if necessary. 142 void set_readable(bool readable); 143 144 // Sets the writable state, signaling if necessary. 145 void set_writable(bool writable); 146 147 148 private: 149 // Used mostly for debugging. 150 std::string content_name_; 151 int component_; 152 bool readable_; 153 bool writable_; 154 155 DISALLOW_EVIL_CONSTRUCTORS(TransportChannel); 156 }; 157 158 } // namespace cricket 159 160 #endif // TALK_P2P_BASE_TRANSPORTCHANNEL_H_ 161
