1// Copyright (c) 2012 The Chromium Authors. All rights reserved.
2// Use of this source code is governed by a BSD-style license that can be
3// found in the LICENSE file.
4//
5// An implementation of buzz::AsyncSocket that uses Chrome sockets.
6
7#ifndef JINGLE_GLUE_CHROME_ASYNC_SOCKET_H_
8#define JINGLE_GLUE_CHROME_ASYNC_SOCKET_H_
9
10#if !defined(FEATURE_ENABLE_SSL)
11#error ChromeAsyncSocket expects FEATURE_ENABLE_SSL to be defined
12#endif
13
14#include <string>
15#include <vector>
16
17#include "base/basictypes.h"
18#include "base/compiler_specific.h"
19#include "base/memory/ref_counted.h"
20#include "base/memory/scoped_ptr.h"
21#include "base/memory/weak_ptr.h"
22#include "net/base/completion_callback.h"
23#include "net/base/net_errors.h"
24#include "third_party/libjingle/source/talk/xmpp/asyncsocket.h"
25
26namespace net {
27class IOBufferWithSize;
28class StreamSocket;
29}  // namespace net
30
31namespace jingle_glue {
32
33class ResolvingClientSocketFactory;
34
35class ChromeAsyncSocket : public buzz::AsyncSocket {
36 public:
37  // Takes ownership of |resolving_client_socket_factory|.
38  ChromeAsyncSocket(
39      ResolvingClientSocketFactory* resolving_client_socket_factory,
40      size_t read_buf_size,
41      size_t write_buf_size);
42
43  // Does not raise any signals.
44  virtual ~ChromeAsyncSocket();
45
46  // buzz::AsyncSocket implementation.
47
48  // The current state (see buzz::AsyncSocket::State; all but
49  // STATE_CLOSING is used).
50  virtual State state() OVERRIDE;
51
52  // The last generated error.  Errors are generated when the main
53  // functions below return false or when SignalClosed is raised due
54  // to an asynchronous error.
55  virtual Error error() OVERRIDE;
56
57  // GetError() (which is of type net::Error) != net::OK only when
58  // error() == ERROR_WINSOCK.
59  virtual int GetError() OVERRIDE;
60
61  // Tries to connect to the given address.
62  //
63  // If state() is not STATE_CLOSED, sets error to ERROR_WRONGSTATE
64  // and returns false.
65  //
66  // If |address| has an empty hostname or a zero port, sets error to
67  // ERROR_DNS and returns false.  (We don't use the IP address even
68  // if it's present, as DNS resolution is done by
69  // |resolving_client_socket_factory_|.  But it's perfectly fine if
70  // the hostname is a stringified IP address.)
71  //
72  // Otherwise, starts the connection process and returns true.
73  // SignalConnected will be raised when the connection is successful;
74  // otherwise, SignalClosed will be raised with a net error set.
75  virtual bool Connect(const rtc::SocketAddress& address) OVERRIDE;
76
77  // Tries to read at most |len| bytes into |data|.
78  //
79  // If state() is not STATE_TLS_CONNECTING, STATE_OPEN, or
80  // STATE_TLS_OPEN, sets error to ERROR_WRONGSTATE and returns false.
81  //
82  // Otherwise, fills in |len_read| with the number of bytes read and
83  // returns true.  If this is called when state() is
84  // STATE_TLS_CONNECTING, reads 0 bytes.  (We have to handle this
85  // case because StartTls() is called during a slot connected to
86  // SignalRead after parsing the final non-TLS reply from the server
87  // [see XmppClient::Private::OnSocketRead()].)
88  virtual bool Read(char* data, size_t len, size_t* len_read) OVERRIDE;
89
90  // Queues up |len| bytes of |data| for writing.
91  //
92  // If state() is not STATE_TLS_CONNECTING, STATE_OPEN, or
93  // STATE_TLS_OPEN, sets error to ERROR_WRONGSTATE and returns false.
94  //
95  // If the given data is too big for the internal write buffer, sets
96  // error to ERROR_WINSOCK/net::ERR_INSUFFICIENT_RESOURCES and
97  // returns false.
98  //
99  // Otherwise, queues up the data and returns true.  If this is
100  // called when state() == STATE_TLS_CONNECTING, the data is will be
101  // sent only after the TLS connection succeeds.  (See StartTls()
102  // below for why this happens.)
103  //
104  // Note that there's no guarantee that the data will actually be
105  // sent; however, it is guaranteed that the any data sent will be
106  // sent in FIFO order.
107  virtual bool Write(const char* data, size_t len) OVERRIDE;
108
109  // If the socket is not already closed, closes the socket and raises
110  // SignalClosed.  Always returns true.
111  virtual bool Close() OVERRIDE;
112
113  // Tries to change to a TLS connection with the given domain name.
114  //
115  // If state() is not STATE_OPEN or there are pending reads or
116  // writes, sets error to ERROR_WRONGSTATE and returns false.  (In
117  // practice, this means that StartTls() can only be called from a
118  // slot connected to SignalRead.)
119  //
120  // Otherwise, starts the TLS connection process and returns true.
121  // SignalSSLConnected will be raised when the connection is
122  // successful; otherwise, SignalClosed will be raised with a net
123  // error set.
124  virtual bool StartTls(const std::string& domain_name) OVERRIDE;
125
126  // Signal behavior:
127  //
128  // SignalConnected: raised whenever the connect initiated by a call
129  // to Connect() is complete.
130  //
131  // SignalSSLConnected: raised whenever the connect initiated by a
132  // call to StartTls() is complete.  Not actually used by
133  // XmppClient. (It just assumes that if SignalRead is raised after a
134  // call to StartTls(), the connection has been successfully
135  // upgraded.)
136  //
137  // SignalClosed: raised whenever the socket is closed, either due to
138  // an asynchronous error, the other side closing the connection, or
139  // when Close() is called.
140  //
141  // SignalRead: raised whenever the next call to Read() will succeed
142  // with a non-zero |len_read| (assuming nothing else happens in the
143  // meantime).
144  //
145  // SignalError: not used.
146
147 private:
148  enum AsyncIOState {
149    // An I/O op is not in progress.
150    IDLE,
151    // A function has been posted to do the I/O.
152    POSTED,
153    // An async I/O operation is pending.
154    PENDING,
155  };
156
157  bool IsOpen() const;
158
159  // Error functions.
160  void DoNonNetError(Error error);
161  void DoNetError(net::Error net_error);
162  void DoNetErrorFromStatus(int status);
163
164  // Connection functions.
165  void ProcessConnectDone(int status);
166
167  // Read loop functions.
168  void PostDoRead();
169  void DoRead();
170  void ProcessReadDone(int status);
171
172  // Write loop functions.
173  void PostDoWrite();
174  void DoWrite();
175  void ProcessWriteDone(int status);
176
177  // SSL/TLS connection functions.
178  void ProcessSSLConnectDone(int status);
179
180  // Close functions.
181  void DoClose();
182
183  scoped_ptr<ResolvingClientSocketFactory> resolving_client_socket_factory_;
184
185  // buzz::AsyncSocket state.
186  buzz::AsyncSocket::State state_;
187  buzz::AsyncSocket::Error error_;
188  net::Error net_error_;
189
190  // NULL iff state() == STATE_CLOSED.
191  scoped_ptr<net::StreamSocket> transport_socket_;
192
193  // State for the read loop.  |read_start_| <= |read_end_| <=
194  // |read_buf_->size()|.  There's a read in flight (i.e.,
195  // |read_state_| != IDLE) iff |read_end_| == 0.
196  AsyncIOState read_state_;
197  scoped_refptr<net::IOBufferWithSize> read_buf_;
198  size_t read_start_, read_end_;
199
200  // State for the write loop.  |write_end_| <= |write_buf_->size()|.
201  // There's a write in flight (i.e., |write_state_| != IDLE) iff
202  // |write_end_| > 0.
203  AsyncIOState write_state_;
204  scoped_refptr<net::IOBufferWithSize> write_buf_;
205  size_t write_end_;
206
207  base::WeakPtrFactory<ChromeAsyncSocket> weak_ptr_factory_;
208
209  DISALLOW_COPY_AND_ASSIGN(ChromeAsyncSocket);
210};
211
212}  // namespace jingle_glue
213
214#endif  // JINGLE_GLUE_CHROME_ASYNC_SOCKET_H_
215