xref: /haiku/src/add-ons/kernel/network/protocols/tcp/tcp.h (revision 3be9edf8da228afd9fec0390f408c964766122aa)
1 /*
2  * Copyright 2006-2008, Haiku, Inc. All Rights Reserved.
3  * Distributed under the terms of the MIT License.
4  *
5  * Authors:
6  *		Axel Dörfler, axeld@pinc-software.de
7  *		Andrew Galante, haiku.galante@gmail.com
8  *		Hugo Santos, hugosantos@gmail.com
9  */
10 #ifndef TCP_H
11 #define TCP_H
12 
13 
14 #include <net_buffer.h>
15 #include <net_datalink.h>
16 #include <net_socket.h>
17 #include <net_stack.h>
18 
19 #include <util/khash.h>
20 
21 #include <ByteOrder.h>
22 
23 #include <sys/socket.h>
24 
25 
26 class EndpointManager;
27 
28 enum tcp_state {
29 	// establishing a connection
30 	CLOSED,
31 	LISTEN,
32 	SYNCHRONIZE_SENT,
33 	SYNCHRONIZE_RECEIVED,
34 	ESTABLISHED,
35 
36 	// peer closes the connection
37 	FINISH_RECEIVED,
38 	WAIT_FOR_FINISH_ACKNOWLEDGE,
39 
40 	// we close the connection
41 	FINISH_SENT,
42 	FINISH_ACKNOWLEDGED,
43 	CLOSING,
44 	TIME_WAIT
45 };
46 
47 struct tcp_header {
48 	uint16 source_port;
49 	uint16 destination_port;
50 	uint32 sequence;
51 	uint32 acknowledge;
52 	struct {
53 #if B_HOST_IS_LENDIAN == 1
54 		uint8 reserved : 4;
55 		uint8 header_length : 4;
56 #else
57 		uint8 header_length : 4;
58 		uint8 reserved : 4;
59 #endif
60 	};
61 	uint8  flags;
62 	uint16 advertised_window;
63 	uint16 checksum;
64 	uint16 urgent_offset;
65 
66 	uint32 HeaderLength() const { return (uint32)header_length << 2; }
67 	uint32 Sequence() const { return ntohl(sequence); }
68 	uint32 Acknowledge() const { return ntohl(acknowledge); }
69 	uint16 AdvertisedWindow() const { return ntohs(advertised_window); }
70 	uint16 Checksum() const { return ntohs(checksum); }
71 	uint16 UrgentOffset() const { return ntohs(urgent_offset); }
72 } _PACKED;
73 
74 class tcp_sequence {
75 public:
76 	inline tcp_sequence() {}
77 	inline tcp_sequence(uint32 sequence)
78 		: fNumber(sequence)
79 	{
80 	}
81 
82 	inline uint32 Number() const
83 	{
84 		return fNumber;
85 	}
86 
87 	inline tcp_sequence& operator=(tcp_sequence sequence)
88 	{
89 		fNumber = sequence.fNumber;
90 		return *this;
91 	}
92 
93 	inline tcp_sequence& operator+=(tcp_sequence sequence)
94 	{
95 		fNumber += sequence.fNumber;
96 		return *this;
97 	}
98 
99 	inline tcp_sequence& operator++()
100 	{
101 		fNumber++;
102 		return *this;
103 	}
104 
105 	inline tcp_sequence operator++(int _)
106 	{
107 		fNumber++;
108 		return fNumber - 1;
109 	}
110 
111 // Conceptually private, but used in global operators.
112 //private:
113 	uint32	fNumber;
114 };
115 
116 
117 // Global tcp_sequence Operators
118 
119 
120 inline bool
121 operator>(tcp_sequence a, tcp_sequence b)
122 {
123 	return (int32)(a.fNumber - b.fNumber) > 0;
124 }
125 
126 
127 inline bool
128 operator>=(tcp_sequence a, tcp_sequence b)
129 {
130 	return (int32)(a.fNumber - b.fNumber) >= 0;
131 }
132 
133 
134 inline bool
135 operator<(tcp_sequence a, tcp_sequence b)
136 {
137 	return (int32)(a.fNumber - b.fNumber) < 0;
138 }
139 
140 
141 inline bool
142 operator<=(tcp_sequence a, tcp_sequence b)
143 {
144 	return (int32)(a.fNumber - b.fNumber) <= 0;
145 }
146 
147 
148 inline tcp_sequence
149 operator+(tcp_sequence a, tcp_sequence b)
150 {
151 	return a.fNumber + b.fNumber;
152 }
153 
154 
155 inline tcp_sequence
156 operator-(tcp_sequence a, tcp_sequence b)
157 {
158 	return a.fNumber - b.fNumber;
159 }
160 
161 
162 inline bool
163 operator!=(tcp_sequence a, tcp_sequence b)
164 {
165 	return a.fNumber != b.fNumber;
166 }
167 
168 
169 inline bool
170 operator==(tcp_sequence a, tcp_sequence b)
171 {
172 	return a.fNumber == b.fNumber;
173 }
174 
175 
176 // TCP flag constants
177 #define TCP_FLAG_FINISH					0x01
178 #define TCP_FLAG_SYNCHRONIZE			0x02
179 #define TCP_FLAG_RESET					0x04
180 #define TCP_FLAG_PUSH					0x08
181 #define TCP_FLAG_ACKNOWLEDGE			0x10
182 #define TCP_FLAG_URGENT					0x20
183 #define TCP_FLAG_CONGESTION_NOTIFICATION_ECHO	0x40
184 #define TCP_FLAG_CONGESTION_WINDOW_REDUCED		0x80
185 
186 #define TCP_CONNECTION_TIMEOUT			75000000	// 75 secs
187 #define TCP_DELAYED_ACKNOWLEDGE_TIMEOUT	100000		// 100 msecs
188 #define TCP_DEFAULT_MAX_SEGMENT_SIZE	536
189 #define TCP_MAX_WINDOW					65535
190 #define TCP_MAX_SEGMENT_LIFETIME		60000000	// 60 secs
191 
192 struct tcp_sack {
193 	uint32 left_edge;
194 	uint32 right_edge;
195 } _PACKED;
196 
197 struct tcp_option {
198 	uint8	kind;
199 	uint8	length;
200 	union {
201 		uint8		window_shift;
202 		uint16		max_segment_size;
203 		struct {
204 			uint32	value;
205 			uint32	reply;
206 		}			timestamp;
207 		tcp_sack	sack[0];
208 	};
209 } _PACKED;
210 
211 enum tcp_option_kind {
212 	TCP_OPTION_END				= 0,
213 	TCP_OPTION_NOP				= 1,
214 	TCP_OPTION_MAX_SEGMENT_SIZE	= 2,
215 	TCP_OPTION_WINDOW_SHIFT		= 3,
216 	TCP_OPTION_SACK_PERMITTED	= 4,
217 	TCP_OPTION_SACK				= 5,
218 	TCP_OPTION_TIMESTAMP		= 8,
219 };
220 
221 #define TCP_MAX_WINDOW_SHIFT	14
222 
223 enum {
224 	TCP_HAS_WINDOW_SCALE	= 1 << 0,
225 	TCP_HAS_TIMESTAMPS		= 1 << 1,
226 	TCP_SACK_PERMITTED		= 1 << 2,
227 };
228 
229 struct tcp_segment_header {
230 	tcp_segment_header(uint8 _flags)
231 		:
232 		flags(_flags),
233 		window_shift(0),
234 		max_segment_size(0),
235 		sack_count(0),
236 		options(0)
237 	{}
238 
239 	uint32	sequence;
240 	uint32	acknowledge;
241 	uint16	advertised_window;
242 	uint16	urgent_offset;
243 	uint8	flags;
244 	uint8	window_shift;
245 	uint16	max_segment_size;
246 
247 	uint32	timestamp_value;
248 	uint32	timestamp_reply;
249 
250 	tcp_sack	*sacks;
251 	int			sack_count;
252 
253 	uint32	options;
254 
255 	bool AcknowledgeOnly() const
256 	{
257 		return (flags & (TCP_FLAG_SYNCHRONIZE | TCP_FLAG_FINISH | TCP_FLAG_RESET
258 			| TCP_FLAG_URGENT | TCP_FLAG_ACKNOWLEDGE)) == TCP_FLAG_ACKNOWLEDGE;
259 	}
260 };
261 
262 enum tcp_segment_action {
263 	KEEP			= 0x00,
264 	DROP			= 0x01,
265 	RESET			= 0x02,
266 	ACKNOWLEDGE		= 0x04,
267 	IMMEDIATE_ACKNOWLEDGE = 0x08,
268 	DELETE_ENDPOINT	= 0x10,
269 };
270 
271 
272 extern net_buffer_module_info* gBufferModule;
273 extern net_datalink_module_info* gDatalinkModule;
274 extern net_socket_module_info* gSocketModule;
275 extern net_stack_module_info* gStackModule;
276 
277 
278 EndpointManager* get_endpoint_manager(net_domain* domain);
279 void put_endpoint_manager(EndpointManager* manager);
280 
281 status_t add_tcp_header(net_address_module_info* addressModule,
282 	tcp_segment_header& segment, net_buffer* buffer);
283 size_t tcp_options_length(tcp_segment_header& segment);
284 
285 const char* name_for_state(tcp_state state);
286 
287 #endif	// TCP_H
288