]>
Commit | Line | Data |
---|---|---|
1da177e4 LT |
1 | /* |
2 | * INET An implementation of the TCP/IP protocol suite for the LINUX | |
3 | * operating system. INET is implemented using the BSD Socket | |
4 | * interface as the means of communication with the user level. | |
5 | * | |
6 | * Definitions for the TCP protocol. | |
7 | * | |
8 | * Version: @(#)tcp.h 1.0.2 04/28/93 | |
9 | * | |
10 | * Author: Fred N. van Kempen, <waltje@uWalt.NL.Mugnet.ORG> | |
11 | * | |
12 | * This program is free software; you can redistribute it and/or | |
13 | * modify it under the terms of the GNU General Public License | |
14 | * as published by the Free Software Foundation; either version | |
15 | * 2 of the License, or (at your option) any later version. | |
16 | */ | |
17 | #ifndef _LINUX_TCP_H | |
18 | #define _LINUX_TCP_H | |
19 | ||
20 | #include <linux/types.h> | |
21 | #include <asm/byteorder.h> | |
22 | ||
23 | struct tcphdr { | |
24 | __u16 source; | |
25 | __u16 dest; | |
26 | __u32 seq; | |
27 | __u32 ack_seq; | |
28 | #if defined(__LITTLE_ENDIAN_BITFIELD) | |
29 | __u16 res1:4, | |
30 | doff:4, | |
31 | fin:1, | |
32 | syn:1, | |
33 | rst:1, | |
34 | psh:1, | |
35 | ack:1, | |
36 | urg:1, | |
37 | ece:1, | |
38 | cwr:1; | |
39 | #elif defined(__BIG_ENDIAN_BITFIELD) | |
40 | __u16 doff:4, | |
41 | res1:4, | |
42 | cwr:1, | |
43 | ece:1, | |
44 | urg:1, | |
45 | ack:1, | |
46 | psh:1, | |
47 | rst:1, | |
48 | syn:1, | |
49 | fin:1; | |
50 | #else | |
51 | #error "Adjust your <asm/byteorder.h> defines" | |
52 | #endif | |
53 | __u16 window; | |
54 | __u16 check; | |
55 | __u16 urg_ptr; | |
56 | }; | |
57 | ||
58 | ||
59 | enum { | |
60 | TCP_ESTABLISHED = 1, | |
61 | TCP_SYN_SENT, | |
62 | TCP_SYN_RECV, | |
63 | TCP_FIN_WAIT1, | |
64 | TCP_FIN_WAIT2, | |
65 | TCP_TIME_WAIT, | |
66 | TCP_CLOSE, | |
67 | TCP_CLOSE_WAIT, | |
68 | TCP_LAST_ACK, | |
69 | TCP_LISTEN, | |
70 | TCP_CLOSING, /* now a valid state */ | |
71 | ||
72 | TCP_MAX_STATES /* Leave at the end! */ | |
73 | }; | |
74 | ||
75 | #define TCP_STATE_MASK 0xF | |
76 | #define TCP_ACTION_FIN (1 << 7) | |
77 | ||
78 | enum { | |
79 | TCPF_ESTABLISHED = (1 << 1), | |
80 | TCPF_SYN_SENT = (1 << 2), | |
81 | TCPF_SYN_RECV = (1 << 3), | |
82 | TCPF_FIN_WAIT1 = (1 << 4), | |
83 | TCPF_FIN_WAIT2 = (1 << 5), | |
84 | TCPF_TIME_WAIT = (1 << 6), | |
85 | TCPF_CLOSE = (1 << 7), | |
86 | TCPF_CLOSE_WAIT = (1 << 8), | |
87 | TCPF_LAST_ACK = (1 << 9), | |
88 | TCPF_LISTEN = (1 << 10), | |
89 | TCPF_CLOSING = (1 << 11) | |
90 | }; | |
91 | ||
92 | /* | |
93 | * The union cast uses a gcc extension to avoid aliasing problems | |
94 | * (union is compatible to any of its members) | |
95 | * This means this part of the code is -fstrict-aliasing safe now. | |
96 | */ | |
97 | union tcp_word_hdr { | |
98 | struct tcphdr hdr; | |
99 | __u32 words[5]; | |
100 | }; | |
101 | ||
102 | #define tcp_flag_word(tp) ( ((union tcp_word_hdr *)(tp))->words [3]) | |
103 | ||
104 | enum { | |
105 | TCP_FLAG_CWR = __constant_htonl(0x00800000), | |
106 | TCP_FLAG_ECE = __constant_htonl(0x00400000), | |
107 | TCP_FLAG_URG = __constant_htonl(0x00200000), | |
108 | TCP_FLAG_ACK = __constant_htonl(0x00100000), | |
109 | TCP_FLAG_PSH = __constant_htonl(0x00080000), | |
110 | TCP_FLAG_RST = __constant_htonl(0x00040000), | |
111 | TCP_FLAG_SYN = __constant_htonl(0x00020000), | |
112 | TCP_FLAG_FIN = __constant_htonl(0x00010000), | |
113 | TCP_RESERVED_BITS = __constant_htonl(0x0F000000), | |
114 | TCP_DATA_OFFSET = __constant_htonl(0xF0000000) | |
115 | }; | |
116 | ||
117 | /* TCP socket options */ | |
118 | #define TCP_NODELAY 1 /* Turn off Nagle's algorithm. */ | |
119 | #define TCP_MAXSEG 2 /* Limit MSS */ | |
120 | #define TCP_CORK 3 /* Never send partially complete segments */ | |
121 | #define TCP_KEEPIDLE 4 /* Start keeplives after this period */ | |
122 | #define TCP_KEEPINTVL 5 /* Interval between keepalives */ | |
123 | #define TCP_KEEPCNT 6 /* Number of keepalives before death */ | |
124 | #define TCP_SYNCNT 7 /* Number of SYN retransmits */ | |
125 | #define TCP_LINGER2 8 /* Life time of orphaned FIN-WAIT-2 state */ | |
126 | #define TCP_DEFER_ACCEPT 9 /* Wake up listener only when data arrive */ | |
127 | #define TCP_WINDOW_CLAMP 10 /* Bound advertised window */ | |
128 | #define TCP_INFO 11 /* Information about this connection. */ | |
129 | #define TCP_QUICKACK 12 /* Block/reenable quick acks */ | |
130 | ||
131 | #define TCPI_OPT_TIMESTAMPS 1 | |
132 | #define TCPI_OPT_SACK 2 | |
133 | #define TCPI_OPT_WSCALE 4 | |
134 | #define TCPI_OPT_ECN 8 | |
135 | ||
136 | enum tcp_ca_state | |
137 | { | |
138 | TCP_CA_Open = 0, | |
139 | #define TCPF_CA_Open (1<<TCP_CA_Open) | |
140 | TCP_CA_Disorder = 1, | |
141 | #define TCPF_CA_Disorder (1<<TCP_CA_Disorder) | |
142 | TCP_CA_CWR = 2, | |
143 | #define TCPF_CA_CWR (1<<TCP_CA_CWR) | |
144 | TCP_CA_Recovery = 3, | |
145 | #define TCPF_CA_Recovery (1<<TCP_CA_Recovery) | |
146 | TCP_CA_Loss = 4 | |
147 | #define TCPF_CA_Loss (1<<TCP_CA_Loss) | |
148 | }; | |
149 | ||
150 | struct tcp_info | |
151 | { | |
152 | __u8 tcpi_state; | |
153 | __u8 tcpi_ca_state; | |
154 | __u8 tcpi_retransmits; | |
155 | __u8 tcpi_probes; | |
156 | __u8 tcpi_backoff; | |
157 | __u8 tcpi_options; | |
158 | __u8 tcpi_snd_wscale : 4, tcpi_rcv_wscale : 4; | |
159 | ||
160 | __u32 tcpi_rto; | |
161 | __u32 tcpi_ato; | |
162 | __u32 tcpi_snd_mss; | |
163 | __u32 tcpi_rcv_mss; | |
164 | ||
165 | __u32 tcpi_unacked; | |
166 | __u32 tcpi_sacked; | |
167 | __u32 tcpi_lost; | |
168 | __u32 tcpi_retrans; | |
169 | __u32 tcpi_fackets; | |
170 | ||
171 | /* Times. */ | |
172 | __u32 tcpi_last_data_sent; | |
173 | __u32 tcpi_last_ack_sent; /* Not remembered, sorry. */ | |
174 | __u32 tcpi_last_data_recv; | |
175 | __u32 tcpi_last_ack_recv; | |
176 | ||
177 | /* Metrics. */ | |
178 | __u32 tcpi_pmtu; | |
179 | __u32 tcpi_rcv_ssthresh; | |
180 | __u32 tcpi_rtt; | |
181 | __u32 tcpi_rttvar; | |
182 | __u32 tcpi_snd_ssthresh; | |
183 | __u32 tcpi_snd_cwnd; | |
184 | __u32 tcpi_advmss; | |
185 | __u32 tcpi_reordering; | |
186 | ||
187 | __u32 tcpi_rcv_rtt; | |
188 | __u32 tcpi_rcv_space; | |
189 | ||
190 | __u32 tcpi_total_retrans; | |
191 | }; | |
192 | ||
193 | #ifdef __KERNEL__ | |
194 | ||
195 | #include <linux/config.h> | |
196 | #include <linux/skbuff.h> | |
197 | #include <linux/ip.h> | |
198 | #include <net/sock.h> | |
199 | ||
200 | /* This defines a selective acknowledgement block. */ | |
201 | struct tcp_sack_block { | |
202 | __u32 start_seq; | |
203 | __u32 end_seq; | |
204 | }; | |
205 | ||
206 | enum tcp_congestion_algo { | |
207 | TCP_RENO=0, | |
208 | TCP_VEGAS, | |
209 | TCP_WESTWOOD, | |
210 | TCP_BIC, | |
211 | }; | |
212 | ||
213 | struct tcp_options_received { | |
214 | /* PAWS/RTTM data */ | |
215 | long ts_recent_stamp;/* Time we stored ts_recent (for aging) */ | |
216 | __u32 ts_recent; /* Time stamp to echo next */ | |
217 | __u32 rcv_tsval; /* Time stamp value */ | |
218 | __u32 rcv_tsecr; /* Time stamp echo reply */ | |
219 | __u16 saw_tstamp : 1, /* Saw TIMESTAMP on last packet */ | |
220 | tstamp_ok : 1, /* TIMESTAMP seen on SYN packet */ | |
221 | dsack : 1, /* D-SACK is scheduled */ | |
222 | wscale_ok : 1, /* Wscale seen on SYN packet */ | |
223 | sack_ok : 4, /* SACK seen on SYN packet */ | |
224 | snd_wscale : 4, /* Window scaling received from sender */ | |
225 | rcv_wscale : 4; /* Window scaling to send to receiver */ | |
226 | /* SACKs data */ | |
227 | __u8 eff_sacks; /* Size of SACK array to send with next packet */ | |
228 | __u8 num_sacks; /* Number of SACK blocks */ | |
229 | __u16 user_mss; /* mss requested by user in ioctl */ | |
230 | __u16 mss_clamp; /* Maximal mss, negotiated at connection setup */ | |
231 | }; | |
232 | ||
2e6599cb ACM |
233 | struct tcp_request_sock { |
234 | struct inet_request_sock req; | |
235 | __u32 rcv_isn; | |
236 | __u32 snt_isn; | |
237 | }; | |
238 | ||
239 | static inline struct tcp_request_sock *tcp_rsk(const struct open_request *req) | |
240 | { | |
241 | return (struct tcp_request_sock *)req; | |
242 | } | |
243 | ||
1da177e4 LT |
244 | struct tcp_sock { |
245 | /* inet_sock has to be the first member of tcp_sock */ | |
246 | struct inet_sock inet; | |
247 | int tcp_header_len; /* Bytes of tcp header to send */ | |
248 | ||
249 | /* | |
250 | * Header prediction flags | |
251 | * 0x5?10 << 16 + snd_wnd in net byte order | |
252 | */ | |
253 | __u32 pred_flags; | |
254 | ||
255 | /* | |
256 | * RFC793 variables by their proper names. This means you can | |
257 | * read the code and the spec side by side (and laugh ...) | |
258 | * See RFC793 and RFC1122. The RFC writes these in capitals. | |
259 | */ | |
260 | __u32 rcv_nxt; /* What we want to receive next */ | |
261 | __u32 snd_nxt; /* Next sequence we send */ | |
262 | ||
263 | __u32 snd_una; /* First byte we want an ack for */ | |
264 | __u32 snd_sml; /* Last byte of the most recently transmitted small packet */ | |
265 | __u32 rcv_tstamp; /* timestamp of last received ACK (for keepalives) */ | |
266 | __u32 lsndtime; /* timestamp of last sent data packet (for restart window) */ | |
267 | struct tcp_bind_bucket *bind_hash; | |
268 | /* Delayed ACK control data */ | |
269 | struct { | |
270 | __u8 pending; /* ACK is pending */ | |
271 | __u8 quick; /* Scheduled number of quick acks */ | |
272 | __u8 pingpong; /* The session is interactive */ | |
273 | __u8 blocked; /* Delayed ACK was blocked by socket lock*/ | |
274 | __u32 ato; /* Predicted tick of soft clock */ | |
275 | unsigned long timeout; /* Currently scheduled timeout */ | |
276 | __u32 lrcvtime; /* timestamp of last received data packet*/ | |
277 | __u16 last_seg_size; /* Size of last incoming segment */ | |
278 | __u16 rcv_mss; /* MSS used for delayed ACK decisions */ | |
279 | } ack; | |
280 | ||
281 | /* Data for direct copy to user */ | |
282 | struct { | |
283 | struct sk_buff_head prequeue; | |
284 | struct task_struct *task; | |
285 | struct iovec *iov; | |
286 | int memory; | |
287 | int len; | |
288 | } ucopy; | |
289 | ||
290 | __u32 snd_wl1; /* Sequence for window update */ | |
291 | __u32 snd_wnd; /* The window we expect to receive */ | |
292 | __u32 max_window; /* Maximal window ever seen from peer */ | |
293 | __u32 pmtu_cookie; /* Last pmtu seen by socket */ | |
294 | __u32 mss_cache; /* Cached effective mss, not including SACKS */ | |
295 | __u16 mss_cache_std; /* Like mss_cache, but without TSO */ | |
296 | __u16 ext_header_len; /* Network protocol overhead (IP/IPv6 options) */ | |
297 | __u8 ca_state; /* State of fast-retransmit machine */ | |
298 | __u8 retransmits; /* Number of unrecovered RTO timeouts. */ | |
299 | ||
300 | __u16 advmss; /* Advertised MSS */ | |
301 | __u32 window_clamp; /* Maximal window to advertise */ | |
302 | __u32 rcv_ssthresh; /* Current window clamp */ | |
303 | ||
304 | __u32 frto_highmark; /* snd_nxt when RTO occurred */ | |
305 | __u8 reordering; /* Packet reordering metric. */ | |
306 | __u8 frto_counter; /* Number of new acks after RTO */ | |
307 | ||
308 | __u8 adv_cong; /* Using Vegas, Westwood, or BIC */ | |
309 | __u8 defer_accept; /* User waits for some data after accept() */ | |
310 | ||
311 | /* RTT measurement */ | |
312 | __u32 srtt; /* smoothed round trip time << 3 */ | |
313 | __u32 mdev; /* medium deviation */ | |
314 | __u32 mdev_max; /* maximal mdev for the last rtt period */ | |
315 | __u32 rttvar; /* smoothed mdev_max */ | |
316 | __u32 rtt_seq; /* sequence number to update rttvar */ | |
317 | __u32 rto; /* retransmit timeout */ | |
318 | ||
319 | __u32 packets_out; /* Packets which are "in flight" */ | |
320 | __u32 left_out; /* Packets which leaved network */ | |
321 | __u32 retrans_out; /* Retransmitted packets out */ | |
322 | __u8 backoff; /* backoff */ | |
323 | /* | |
324 | * Options received (usually on last packet, some only on SYN packets). | |
325 | */ | |
326 | __u8 nonagle; /* Disable Nagle algorithm? */ | |
327 | __u8 keepalive_probes; /* num of allowed keep alive probes */ | |
328 | ||
329 | __u8 probes_out; /* unanswered 0 window probes */ | |
330 | struct tcp_options_received rx_opt; | |
331 | ||
332 | /* | |
333 | * Slow start and congestion control (see also Nagle, and Karn & Partridge) | |
334 | */ | |
335 | __u32 snd_ssthresh; /* Slow start size threshold */ | |
336 | __u32 snd_cwnd; /* Sending congestion window */ | |
337 | __u16 snd_cwnd_cnt; /* Linear increase counter */ | |
338 | __u16 snd_cwnd_clamp; /* Do not allow snd_cwnd to grow above this */ | |
339 | __u32 snd_cwnd_used; | |
340 | __u32 snd_cwnd_stamp; | |
341 | ||
342 | /* Two commonly used timers in both sender and receiver paths. */ | |
343 | unsigned long timeout; | |
344 | struct timer_list retransmit_timer; /* Resend (no ack) */ | |
345 | struct timer_list delack_timer; /* Ack delay */ | |
346 | ||
347 | struct sk_buff_head out_of_order_queue; /* Out of order segments go here */ | |
348 | ||
349 | struct tcp_func *af_specific; /* Operations which are AF_INET{4,6} specific */ | |
350 | ||
351 | __u32 rcv_wnd; /* Current receiver window */ | |
352 | __u32 rcv_wup; /* rcv_nxt on last window update sent */ | |
353 | __u32 write_seq; /* Tail(+1) of data held in tcp send buffer */ | |
354 | __u32 pushed_seq; /* Last pushed seq, required to talk to windows */ | |
355 | __u32 copied_seq; /* Head of yet unread data */ | |
356 | ||
357 | /* SACKs data */ | |
358 | struct tcp_sack_block duplicate_sack[1]; /* D-SACK block */ | |
359 | struct tcp_sack_block selective_acks[4]; /* The SACKS themselves*/ | |
360 | ||
361 | __u8 syn_retries; /* num of allowed syn retries */ | |
362 | __u8 ecn_flags; /* ECN status bits. */ | |
363 | __u16 prior_ssthresh; /* ssthresh saved at recovery start */ | |
364 | __u32 lost_out; /* Lost packets */ | |
365 | __u32 sacked_out; /* SACK'd packets */ | |
366 | __u32 fackets_out; /* FACK'd packets */ | |
367 | __u32 high_seq; /* snd_nxt at onset of congestion */ | |
368 | ||
369 | __u32 retrans_stamp; /* Timestamp of the last retransmit, | |
370 | * also used in SYN-SENT to remember stamp of | |
371 | * the first SYN. */ | |
372 | __u32 undo_marker; /* tracking retrans started here. */ | |
373 | int undo_retrans; /* number of undoable retransmissions. */ | |
374 | __u32 urg_seq; /* Seq of received urgent pointer */ | |
375 | __u16 urg_data; /* Saved octet of OOB data and control flags */ | |
376 | __u8 pending; /* Scheduled timer event */ | |
377 | __u8 urg_mode; /* In urgent mode */ | |
378 | __u32 snd_up; /* Urgent pointer */ | |
379 | ||
380 | __u32 total_retrans; /* Total retransmits for entire connection */ | |
381 | ||
382 | /* The syn_wait_lock is necessary only to avoid proc interface having | |
383 | * to grab the main lock sock while browsing the listening hash | |
384 | * (otherwise it's deadlock prone). | |
385 | * This lock is acquired in read mode only from listening_get_next() | |
386 | * and it's acquired in write mode _only_ from code that is actively | |
387 | * changing the syn_wait_queue. All readers that are holding | |
388 | * the master sock lock don't need to grab this lock in read mode | |
389 | * too as the syn_wait_queue writes are always protected from | |
390 | * the main sock lock. | |
391 | */ | |
392 | rwlock_t syn_wait_lock; | |
393 | struct tcp_listen_opt *listen_opt; | |
394 | ||
395 | /* FIFO of established children */ | |
396 | struct open_request *accept_queue; | |
397 | struct open_request *accept_queue_tail; | |
398 | ||
399 | unsigned int keepalive_time; /* time before keep alive takes place */ | |
400 | unsigned int keepalive_intvl; /* time interval between keep alive probes */ | |
401 | int linger2; | |
402 | ||
403 | unsigned long last_synq_overflow; | |
404 | ||
405 | /* Receiver side RTT estimation */ | |
406 | struct { | |
407 | __u32 rtt; | |
408 | __u32 seq; | |
409 | __u32 time; | |
410 | } rcv_rtt_est; | |
411 | ||
412 | /* Receiver queue space */ | |
413 | struct { | |
414 | int space; | |
415 | __u32 seq; | |
416 | __u32 time; | |
417 | } rcvq_space; | |
418 | ||
419 | /* TCP Westwood structure */ | |
420 | struct { | |
421 | __u32 bw_ns_est; /* first bandwidth estimation..not too smoothed 8) */ | |
422 | __u32 bw_est; /* bandwidth estimate */ | |
423 | __u32 rtt_win_sx; /* here starts a new evaluation... */ | |
424 | __u32 bk; | |
425 | __u32 snd_una; /* used for evaluating the number of acked bytes */ | |
426 | __u32 cumul_ack; | |
427 | __u32 accounted; | |
428 | __u32 rtt; | |
429 | __u32 rtt_min; /* minimum observed RTT */ | |
430 | } westwood; | |
431 | ||
432 | /* Vegas variables */ | |
433 | struct { | |
434 | __u32 beg_snd_nxt; /* right edge during last RTT */ | |
435 | __u32 beg_snd_una; /* left edge during last RTT */ | |
436 | __u32 beg_snd_cwnd; /* saves the size of the cwnd */ | |
437 | __u8 doing_vegas_now;/* if true, do vegas for this RTT */ | |
438 | __u16 cntRTT; /* # of RTTs measured within last RTT */ | |
439 | __u32 minRTT; /* min of RTTs measured within last RTT (in usec) */ | |
440 | __u32 baseRTT; /* the min of all Vegas RTT measurements seen (in usec) */ | |
441 | } vegas; | |
442 | ||
443 | /* BI TCP Parameters */ | |
444 | struct { | |
445 | __u32 cnt; /* increase cwnd by 1 after this number of ACKs */ | |
446 | __u32 last_max_cwnd; /* last maximium snd_cwnd */ | |
447 | __u32 last_cwnd; /* the last snd_cwnd */ | |
448 | __u32 last_stamp; /* time when updated last_cwnd */ | |
449 | } bictcp; | |
450 | }; | |
451 | ||
452 | static inline struct tcp_sock *tcp_sk(const struct sock *sk) | |
453 | { | |
454 | return (struct tcp_sock *)sk; | |
455 | } | |
456 | ||
457 | #endif | |
458 | ||
459 | #endif /* _LINUX_TCP_H */ |