[TCPIP]
[reactos.git] / reactos / lib / drivers / lwip / src / include / lwip / tcp.h
1 /*
2 * Copyright (c) 2001-2004 Swedish Institute of Computer Science.
3 * All rights reserved.
4 *
5 * Redistribution and use in source and binary forms, with or without modification,
6 * 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 EVENT
19 * SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
20 * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT
21 * OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
22 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
23 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING
24 * IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY
25 * OF SUCH DAMAGE.
26 *
27 * This file is part of the lwIP TCP/IP stack.
28 *
29 * Author: Adam Dunkels <adam@sics.se>
30 *
31 */
32 #ifndef __LWIP_TCP_H__
33 #define __LWIP_TCP_H__
34
35 #include "lwip/opt.h"
36
37 #if LWIP_TCP /* don't build if not configured for use in lwipopts.h */
38
39 #include "lwip/sys.h"
40 #include "lwip/mem.h"
41 #include "lwip/pbuf.h"
42 #include "lwip/ip.h"
43 #include "lwip/icmp.h"
44 #include "lwip/err.h"
45
46 #ifdef __cplusplus
47 extern "C" {
48 #endif
49
50 struct tcp_pcb;
51
52 /** Function prototype for tcp accept callback functions. Called when a new
53 * connection can be accepted on a listening pcb.
54 *
55 * @param arg Additional argument to pass to the callback function (@see tcp_arg())
56 * @param newpcb The new connection pcb
57 * @param err An error code if there has been an error accepting.
58 * Only return ERR_ABRT if you have called tcp_abort from within the
59 * callback function!
60 */
61 typedef err_t (*tcp_accept_fn)(void *arg, struct tcp_pcb *newpcb, err_t err);
62
63 /** Function prototype for tcp receive callback functions. Called when data has
64 * been received.
65 *
66 * @param arg Additional argument to pass to the callback function (@see tcp_arg())
67 * @param tpcb The connection pcb which received data
68 * @param p The received data (or NULL when the connection has been closed!)
69 * @param err An error code if there has been an error receiving
70 * Only return ERR_ABRT if you have called tcp_abort from within the
71 * callback function!
72 */
73 typedef err_t (*tcp_recv_fn)(void *arg, struct tcp_pcb *tpcb,
74 struct pbuf *p, err_t err);
75
76 /** Function prototype for tcp sent callback functions. Called when sent data has
77 * been acknowledged by the remote side. Use it to free corresponding resources.
78 * This also means that the pcb has now space available to send new data.
79 *
80 * @param arg Additional argument to pass to the callback function (@see tcp_arg())
81 * @param tpcb The connection pcb for which data has been acknowledged
82 * @param len The amount of bytes acknowledged
83 * @return ERR_OK: try to send some data by calling tcp_output
84 * Only return ERR_ABRT if you have called tcp_abort from within the
85 * callback function!
86 */
87 typedef err_t (*tcp_sent_fn)(void *arg, struct tcp_pcb *tpcb,
88 u16_t len);
89
90 /** Function prototype for tcp poll callback functions. Called periodically as
91 * specified by @see tcp_poll.
92 *
93 * @param arg Additional argument to pass to the callback function (@see tcp_arg())
94 * @param tpcb tcp pcb
95 * @return ERR_OK: try to send some data by calling tcp_output
96 * Only return ERR_ABRT if you have called tcp_abort from within the
97 * callback function!
98 */
99 typedef err_t (*tcp_poll_fn)(void *arg, struct tcp_pcb *tpcb);
100
101 /** Function prototype for tcp error callback functions. Called when the pcb
102 * receives a RST or is unexpectedly closed for any other reason.
103 *
104 * @note The corresponding pcb is already freed when this callback is called!
105 *
106 * @param arg Additional argument to pass to the callback function (@see tcp_arg())
107 * @param err Error code to indicate why the pcb has been closed
108 * ERR_ABRT: aborted through tcp_abort or by a TCP timer
109 * ERR_RST: the connection was reset by the remote host
110 */
111 typedef void (*tcp_err_fn)(void *arg, err_t err);
112
113 /** Function prototype for tcp connected callback functions. Called when a pcb
114 * is connected to the remote side after initiating a connection attempt by
115 * calling tcp_connect().
116 *
117 * @param arg Additional argument to pass to the callback function (@see tcp_arg())
118 * @param tpcb The connection pcb which is connected
119 * @param err An unused error code, always ERR_OK currently ;-) TODO!
120 * Only return ERR_ABRT if you have called tcp_abort from within the
121 * callback function!
122 *
123 * @note When a connection attempt fails, the error callback is currently called!
124 */
125 typedef err_t (*tcp_connected_fn)(void *arg, struct tcp_pcb *tpcb, err_t err);
126
127 enum tcp_state {
128 CLOSED = 0,
129 LISTEN = 1,
130 SYN_SENT = 2,
131 SYN_RCVD = 3,
132 ESTABLISHED = 4,
133 FIN_WAIT_1 = 5,
134 FIN_WAIT_2 = 6,
135 CLOSE_WAIT = 7,
136 CLOSING = 8,
137 LAST_ACK = 9,
138 TIME_WAIT = 10
139 };
140
141 #if LWIP_CALLBACK_API
142 /* Function to call when a listener has been connected.
143 * @param arg user-supplied argument (tcp_pcb.callback_arg)
144 * @param pcb a new tcp_pcb that now is connected
145 * @param err an error argument (TODO: that is current always ERR_OK?)
146 * @return ERR_OK: accept the new connection,
147 * any other err_t abortsthe new connection
148 */
149 #define DEF_ACCEPT_CALLBACK tcp_accept_fn accept;
150 #else /* LWIP_CALLBACK_API */
151 #define DEF_ACCEPT_CALLBACK
152 #endif /* LWIP_CALLBACK_API */
153
154 /**
155 * members common to struct tcp_pcb and struct tcp_listen_pcb
156 */
157 #define TCP_PCB_COMMON(type) \
158 type *next; /* for the linked list */ \
159 enum tcp_state state; /* TCP state */ \
160 u8_t prio; \
161 void *callback_arg; \
162 /* the accept callback for listen- and normal pcbs, if LWIP_CALLBACK_API */ \
163 DEF_ACCEPT_CALLBACK \
164 /* ports are in host byte order */ \
165 u16_t local_port
166
167
168 /* the TCP protocol control block */
169 struct tcp_pcb {
170 /** common PCB members */
171 IP_PCB;
172 /** protocol specific PCB members */
173 TCP_PCB_COMMON(struct tcp_pcb);
174
175 /* ports are in host byte order */
176 u16_t remote_port;
177
178 u8_t flags;
179 #define TF_ACK_DELAY ((u8_t)0x01U) /* Delayed ACK. */
180 #define TF_ACK_NOW ((u8_t)0x02U) /* Immediate ACK. */
181 #define TF_INFR ((u8_t)0x04U) /* In fast recovery. */
182 #define TF_TIMESTAMP ((u8_t)0x08U) /* Timestamp option enabled */
183 #define TF_RXCLOSED ((u8_t)0x10U) /* rx closed by tcp_shutdown */
184 #define TF_FIN ((u8_t)0x20U) /* Connection was closed locally (FIN segment enqueued). */
185 #define TF_NODELAY ((u8_t)0x40U) /* Disable Nagle algorithm */
186 #define TF_NAGLEMEMERR ((u8_t)0x80U) /* nagle enabled, memerr, try to output to prevent delayed ACK to happen */
187
188 /* the rest of the fields are in host byte order
189 as we have to do some math with them */
190 /* receiver variables */
191 u32_t rcv_nxt; /* next seqno expected */
192 u16_t rcv_wnd; /* receiver window available */
193 u16_t rcv_ann_wnd; /* receiver window to announce */
194 u32_t rcv_ann_right_edge; /* announced right edge of window */
195
196 /* Timers */
197 u32_t tmr;
198 u8_t polltmr, pollinterval;
199
200 /* Retransmission timer. */
201 s16_t rtime;
202
203 u16_t mss; /* maximum segment size */
204
205 /* RTT (round trip time) estimation variables */
206 u32_t rttest; /* RTT estimate in 500ms ticks */
207 u32_t rtseq; /* sequence number being timed */
208 s16_t sa, sv; /* @todo document this */
209
210 s16_t rto; /* retransmission time-out */
211 u8_t nrtx; /* number of retransmissions */
212
213 /* fast retransmit/recovery */
214 u32_t lastack; /* Highest acknowledged seqno. */
215 u8_t dupacks;
216
217 /* congestion avoidance/control variables */
218 u16_t cwnd;
219 u16_t ssthresh;
220
221 /* sender variables */
222 u32_t snd_nxt; /* next new seqno to be sent */
223 u16_t snd_wnd; /* sender window */
224 u32_t snd_wl1, snd_wl2; /* Sequence and acknowledgement numbers of last
225 window update. */
226 u32_t snd_lbb; /* Sequence number of next byte to be buffered. */
227
228 u16_t acked;
229
230 u16_t snd_buf; /* Available buffer space for sending (in bytes). */
231 #define TCP_SNDQUEUELEN_OVERFLOW (0xffffU-3)
232 u16_t snd_queuelen; /* Available buffer space for sending (in tcp_segs). */
233
234 #if TCP_OVERSIZE
235 /* Extra bytes available at the end of the last pbuf in unsent. */
236 u16_t unsent_oversize;
237 #endif /* TCP_OVERSIZE */
238
239 /* These are ordered by sequence number: */
240 struct tcp_seg *unsent; /* Unsent (queued) segments. */
241 struct tcp_seg *unacked; /* Sent but unacknowledged segments. */
242 #if TCP_QUEUE_OOSEQ
243 struct tcp_seg *ooseq; /* Received out of sequence segments. */
244 #endif /* TCP_QUEUE_OOSEQ */
245
246 struct pbuf *refused_data; /* Data previously received but not yet taken by upper layer */
247
248 #if LWIP_CALLBACK_API
249 /* Function to be called when more send buffer space is available. */
250 tcp_sent_fn sent;
251 /* Function to be called when (in-sequence) data has arrived. */
252 tcp_recv_fn recv;
253 /* Function to be called when a connection has been set up. */
254 tcp_connected_fn connected;
255 /* Function which is called periodically. */
256 tcp_poll_fn poll;
257 /* Function to be called whenever a fatal error occurs. */
258 tcp_err_fn errf;
259 #endif /* LWIP_CALLBACK_API */
260
261 #if LWIP_TCP_TIMESTAMPS
262 u32_t ts_lastacksent;
263 u32_t ts_recent;
264 #endif /* LWIP_TCP_TIMESTAMPS */
265
266 /* idle time before KEEPALIVE is sent */
267 u32_t keep_idle;
268 #if LWIP_TCP_KEEPALIVE
269 u32_t keep_intvl;
270 u32_t keep_cnt;
271 #endif /* LWIP_TCP_KEEPALIVE */
272
273 /* Persist timer counter */
274 u32_t persist_cnt;
275 /* Persist timer back-off */
276 u8_t persist_backoff;
277
278 /* KEEPALIVE counter */
279 u8_t keep_cnt_sent;
280 };
281
282 struct tcp_pcb_listen {
283 /* Common members of all PCB types */
284 IP_PCB;
285 /* Protocol specific PCB members */
286 TCP_PCB_COMMON(struct tcp_pcb_listen);
287
288 #if TCP_LISTEN_BACKLOG
289 u8_t backlog;
290 u8_t accepts_pending;
291 #endif /* TCP_LISTEN_BACKLOG */
292 };
293
294 #if LWIP_EVENT_API
295
296 enum lwip_event {
297 LWIP_EVENT_ACCEPT,
298 LWIP_EVENT_SENT,
299 LWIP_EVENT_RECV,
300 LWIP_EVENT_CONNECTED,
301 LWIP_EVENT_POLL,
302 LWIP_EVENT_ERR
303 };
304
305 err_t lwip_tcp_event(void *arg, struct tcp_pcb *pcb,
306 enum lwip_event,
307 struct pbuf *p,
308 u16_t size,
309 err_t err);
310
311 #endif /* LWIP_EVENT_API */
312
313 /* Application program's interface: */
314 struct tcp_pcb * tcp_new (void);
315
316 void tcp_arg (struct tcp_pcb *pcb, void *arg);
317 void tcp_accept (struct tcp_pcb *pcb, tcp_accept_fn accept);
318 void tcp_recv (struct tcp_pcb *pcb, tcp_recv_fn recv);
319 void tcp_sent (struct tcp_pcb *pcb, tcp_sent_fn sent);
320 void tcp_poll (struct tcp_pcb *pcb, tcp_poll_fn poll, u8_t interval);
321 void tcp_err (struct tcp_pcb *pcb, tcp_err_fn err);
322
323 #define tcp_mss(pcb) (((pcb)->flags & TF_TIMESTAMP) ? ((pcb)->mss - 12) : (pcb)->mss)
324 #define tcp_sndbuf(pcb) ((pcb)->snd_buf)
325 #define tcp_sndqueuelen(pcb) ((pcb)->snd_queuelen)
326 #define tcp_nagle_disable(pcb) ((pcb)->flags |= TF_NODELAY)
327 #define tcp_nagle_enable(pcb) ((pcb)->flags &= ~TF_NODELAY)
328 #define tcp_nagle_disabled(pcb) (((pcb)->flags & TF_NODELAY) != 0)
329
330 #if TCP_LISTEN_BACKLOG
331 #define tcp_accepted(pcb) do { \
332 LWIP_ASSERT("pcb->state == LISTEN (called for wrong pcb?)", pcb->state == LISTEN); \
333 (((struct tcp_pcb_listen *)(pcb))->accepts_pending--); } while(0)
334 #else /* TCP_LISTEN_BACKLOG */
335 #define tcp_accepted(pcb) LWIP_ASSERT("pcb->state == LISTEN (called for wrong pcb?)", \
336 pcb->state == LISTEN)
337 #endif /* TCP_LISTEN_BACKLOG */
338
339 void tcp_recved (struct tcp_pcb *pcb, u16_t len);
340 err_t tcp_bind (struct tcp_pcb *pcb, ip_addr_t *ipaddr,
341 u16_t port);
342 err_t tcp_connect (struct tcp_pcb *pcb, ip_addr_t *ipaddr,
343 u16_t port, tcp_connected_fn connected);
344
345 struct tcp_pcb * tcp_listen_with_backlog(struct tcp_pcb *pcb, u8_t backlog);
346 #define tcp_listen(pcb) tcp_listen_with_backlog(pcb, TCP_DEFAULT_LISTEN_BACKLOG)
347
348 void tcp_abort (struct tcp_pcb *pcb);
349 err_t tcp_close (struct tcp_pcb *pcb);
350 err_t tcp_shutdown(struct tcp_pcb *pcb, int shut_rx, int shut_tx);
351
352 /* Flags for "apiflags" parameter in tcp_write */
353 #define TCP_WRITE_FLAG_COPY 0x01
354 #define TCP_WRITE_FLAG_MORE 0x02
355
356 err_t tcp_write (struct tcp_pcb *pcb, const void *dataptr, u16_t len,
357 u8_t apiflags);
358
359 void tcp_setprio (struct tcp_pcb *pcb, u8_t prio);
360
361 #define TCP_PRIO_MIN 1
362 #define TCP_PRIO_NORMAL 64
363 #define TCP_PRIO_MAX 127
364
365 err_t tcp_output (struct tcp_pcb *pcb);
366
367
368 const char* tcp_debug_state_str(enum tcp_state s);
369
370
371 #ifdef __cplusplus
372 }
373 #endif
374
375 #endif /* LWIP_TCP */
376
377 #endif /* __LWIP_TCP_H__ */