xref: /aosp_15_r20/external/cronet/net/socket/socks5_client_socket.h (revision 6777b5387eb2ff775bb5750e3f5d96f37fb7352b)
1 // Copyright 2012 The Chromium Authors
2 // Use of this source code is governed by a BSD-style license that can be
3 // found in the LICENSE file.
4 
5 #ifndef NET_SOCKET_SOCKS5_CLIENT_SOCKET_H_
6 #define NET_SOCKET_SOCKS5_CLIENT_SOCKET_H_
7 
8 #include <stddef.h>
9 #include <stdint.h>
10 
11 #include <memory>
12 #include <string>
13 
14 #include "base/memory/scoped_refptr.h"
15 #include "net/base/address_list.h"
16 #include "net/base/completion_once_callback.h"
17 #include "net/base/completion_repeating_callback.h"
18 #include "net/base/host_port_pair.h"
19 #include "net/base/net_errors.h"
20 #include "net/base/net_export.h"
21 #include "net/log/net_log_with_source.h"
22 #include "net/socket/stream_socket.h"
23 #include "net/traffic_annotation/network_traffic_annotation.h"
24 #include "url/gurl.h"
25 
26 namespace net {
27 
28 // This StreamSocket is used to setup a SOCKSv5 handshake with a socks proxy.
29 // Currently no SOCKSv5 authentication is supported.
30 class NET_EXPORT_PRIVATE SOCKS5ClientSocket : public StreamSocket {
31  public:
32   // |destination| contains the hostname and port to which the socket above will
33   // communicate to via the SOCKS layer.
34   //
35   // Although SOCKS 5 supports 3 different modes of addressing, we will
36   // always pass it a hostname. This means the DNS resolving is done
37   // proxy side.
38   SOCKS5ClientSocket(std::unique_ptr<StreamSocket> transport_socket,
39                      const HostPortPair& destination,
40                      const NetworkTrafficAnnotationTag& traffic_annotation);
41 
42   SOCKS5ClientSocket(const SOCKS5ClientSocket&) = delete;
43   SOCKS5ClientSocket& operator=(const SOCKS5ClientSocket&) = delete;
44 
45   // On destruction Disconnect() is called.
46   ~SOCKS5ClientSocket() override;
47 
48   // StreamSocket implementation.
49 
50   // Does the SOCKS handshake and completes the protocol.
51   int Connect(CompletionOnceCallback callback) override;
52   void Disconnect() override;
53   bool IsConnected() const override;
54   bool IsConnectedAndIdle() const override;
55   const NetLogWithSource& NetLog() const override;
56   bool WasEverUsed() const override;
57   NextProto GetNegotiatedProtocol() const override;
58   bool GetSSLInfo(SSLInfo* ssl_info) override;
59   int64_t GetTotalReceivedBytes() const override;
60   void ApplySocketTag(const SocketTag& tag) override;
61 
62   // Socket implementation.
63   int Read(IOBuffer* buf,
64            int buf_len,
65            CompletionOnceCallback callback) override;
66   int Write(IOBuffer* buf,
67             int buf_len,
68             CompletionOnceCallback callback,
69             const NetworkTrafficAnnotationTag& traffic_annotation) override;
70 
71   int SetReceiveBufferSize(int32_t size) override;
72   int SetSendBufferSize(int32_t size) override;
73 
74   int GetPeerAddress(IPEndPoint* address) const override;
75   int GetLocalAddress(IPEndPoint* address) const override;
76 
77  private:
78   enum State {
79     STATE_GREET_WRITE,
80     STATE_GREET_WRITE_COMPLETE,
81     STATE_GREET_READ,
82     STATE_GREET_READ_COMPLETE,
83     STATE_HANDSHAKE_WRITE,
84     STATE_HANDSHAKE_WRITE_COMPLETE,
85     STATE_HANDSHAKE_READ,
86     STATE_HANDSHAKE_READ_COMPLETE,
87     STATE_NONE,
88   };
89 
90   // Addressing type that can be specified in requests or responses.
91   enum SocksEndPointAddressType {
92     kEndPointDomain = 0x03,
93     kEndPointResolvedIPv4 = 0x01,
94     kEndPointResolvedIPv6 = 0x04,
95   };
96 
97   static const unsigned int kGreetReadHeaderSize;
98   static const unsigned int kWriteHeaderSize;
99   static const unsigned int kReadHeaderSize;
100   static const uint8_t kSOCKS5Version;
101   static const uint8_t kTunnelCommand;
102   static const uint8_t kNullByte;
103 
104   void DoCallback(int result);
105   void OnIOComplete(int result);
106   void OnReadWriteComplete(CompletionOnceCallback callback, int result);
107 
108   int DoLoop(int last_io_result);
109   int DoHandshakeRead();
110   int DoHandshakeReadComplete(int result);
111   int DoHandshakeWrite();
112   int DoHandshakeWriteComplete(int result);
113   int DoGreetRead();
114   int DoGreetReadComplete(int result);
115   int DoGreetWrite();
116   int DoGreetWriteComplete(int result);
117 
118   // Writes the SOCKS handshake buffer into |handshake|
119   // and return OK on success.
120   int BuildHandshakeWriteBuffer(std::string* handshake) const;
121 
122   CompletionRepeatingCallback io_callback_;
123 
124   // Stores the underlying socket.
125   std::unique_ptr<StreamSocket> transport_socket_;
126 
127   State next_state_ = STATE_NONE;
128 
129   // Stores the callback to the layer above, called on completing Connect().
130   CompletionOnceCallback user_callback_;
131 
132   // This IOBuffer is used by the class to read and write
133   // SOCKS handshake data. The length contains the expected size to
134   // read or write.
135   scoped_refptr<IOBuffer> handshake_buf_;
136 
137   // While writing, this buffer stores the complete write handshake data.
138   // While reading, it stores the handshake information received so far.
139   std::string buffer_;
140 
141   // This becomes true when the SOCKS handshake has completed and the
142   // overlying connection is free to communicate.
143   bool completed_handshake_ = false;
144 
145   // These contain the bytes sent / received by the SOCKS handshake.
146   size_t bytes_sent_ = 0;
147   size_t bytes_received_ = 0;
148 
149   size_t read_header_size;
150 
151   bool was_ever_used_ = false;
152 
153   const HostPortPair destination_;
154 
155   NetLogWithSource net_log_;
156 
157   // Traffic annotation for socket control.
158   NetworkTrafficAnnotationTag traffic_annotation_;
159 };
160 
161 }  // namespace net
162 
163 #endif  // NET_SOCKET_SOCKS5_CLIENT_SOCKET_H_
164