Commit | Line | Data |
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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> | |
cfb6eeb4 | 22 | #include <linux/socket.h> |
1da177e4 LT |
23 | |
24 | struct tcphdr { | |
46a97324 AV |
25 | __be16 source; |
26 | __be16 dest; | |
27 | __be32 seq; | |
28 | __be32 ack_seq; | |
1da177e4 LT |
29 | #if defined(__LITTLE_ENDIAN_BITFIELD) |
30 | __u16 res1:4, | |
31 | doff:4, | |
32 | fin:1, | |
33 | syn:1, | |
34 | rst:1, | |
35 | psh:1, | |
36 | ack:1, | |
37 | urg:1, | |
38 | ece:1, | |
39 | cwr:1; | |
40 | #elif defined(__BIG_ENDIAN_BITFIELD) | |
41 | __u16 doff:4, | |
42 | res1:4, | |
43 | cwr:1, | |
44 | ece:1, | |
45 | urg:1, | |
46 | ack:1, | |
47 | psh:1, | |
48 | rst:1, | |
49 | syn:1, | |
50 | fin:1; | |
51 | #else | |
52 | #error "Adjust your <asm/byteorder.h> defines" | |
53 | #endif | |
46a97324 | 54 | __be16 window; |
9981a0e3 | 55 | __sum16 check; |
46a97324 | 56 | __be16 urg_ptr; |
1da177e4 LT |
57 | }; |
58 | ||
1da177e4 LT |
59 | /* |
60 | * The union cast uses a gcc extension to avoid aliasing problems | |
61 | * (union is compatible to any of its members) | |
62 | * This means this part of the code is -fstrict-aliasing safe now. | |
63 | */ | |
64 | union tcp_word_hdr { | |
65 | struct tcphdr hdr; | |
46a97324 | 66 | __be32 words[5]; |
1da177e4 LT |
67 | }; |
68 | ||
69 | #define tcp_flag_word(tp) ( ((union tcp_word_hdr *)(tp))->words [3]) | |
70 | ||
71 | enum { | |
72 | TCP_FLAG_CWR = __constant_htonl(0x00800000), | |
73 | TCP_FLAG_ECE = __constant_htonl(0x00400000), | |
74 | TCP_FLAG_URG = __constant_htonl(0x00200000), | |
75 | TCP_FLAG_ACK = __constant_htonl(0x00100000), | |
76 | TCP_FLAG_PSH = __constant_htonl(0x00080000), | |
77 | TCP_FLAG_RST = __constant_htonl(0x00040000), | |
78 | TCP_FLAG_SYN = __constant_htonl(0x00020000), | |
79 | TCP_FLAG_FIN = __constant_htonl(0x00010000), | |
80 | TCP_RESERVED_BITS = __constant_htonl(0x0F000000), | |
81 | TCP_DATA_OFFSET = __constant_htonl(0xF0000000) | |
82 | }; | |
83 | ||
84 | /* TCP socket options */ | |
85 | #define TCP_NODELAY 1 /* Turn off Nagle's algorithm. */ | |
86 | #define TCP_MAXSEG 2 /* Limit MSS */ | |
87 | #define TCP_CORK 3 /* Never send partially complete segments */ | |
88 | #define TCP_KEEPIDLE 4 /* Start keeplives after this period */ | |
89 | #define TCP_KEEPINTVL 5 /* Interval between keepalives */ | |
90 | #define TCP_KEEPCNT 6 /* Number of keepalives before death */ | |
91 | #define TCP_SYNCNT 7 /* Number of SYN retransmits */ | |
92 | #define TCP_LINGER2 8 /* Life time of orphaned FIN-WAIT-2 state */ | |
93 | #define TCP_DEFER_ACCEPT 9 /* Wake up listener only when data arrive */ | |
94 | #define TCP_WINDOW_CLAMP 10 /* Bound advertised window */ | |
95 | #define TCP_INFO 11 /* Information about this connection. */ | |
96 | #define TCP_QUICKACK 12 /* Block/reenable quick acks */ | |
5f8ef48d | 97 | #define TCP_CONGESTION 13 /* Congestion control algorithm */ |
cfb6eeb4 | 98 | #define TCP_MD5SIG 14 /* TCP MD5 Signature (RFC2385) */ |
1da177e4 LT |
99 | |
100 | #define TCPI_OPT_TIMESTAMPS 1 | |
101 | #define TCPI_OPT_SACK 2 | |
102 | #define TCPI_OPT_WSCALE 4 | |
103 | #define TCPI_OPT_ECN 8 | |
104 | ||
105 | enum tcp_ca_state | |
106 | { | |
107 | TCP_CA_Open = 0, | |
108 | #define TCPF_CA_Open (1<<TCP_CA_Open) | |
109 | TCP_CA_Disorder = 1, | |
110 | #define TCPF_CA_Disorder (1<<TCP_CA_Disorder) | |
111 | TCP_CA_CWR = 2, | |
112 | #define TCPF_CA_CWR (1<<TCP_CA_CWR) | |
113 | TCP_CA_Recovery = 3, | |
114 | #define TCPF_CA_Recovery (1<<TCP_CA_Recovery) | |
115 | TCP_CA_Loss = 4 | |
116 | #define TCPF_CA_Loss (1<<TCP_CA_Loss) | |
117 | }; | |
118 | ||
119 | struct tcp_info | |
120 | { | |
121 | __u8 tcpi_state; | |
122 | __u8 tcpi_ca_state; | |
123 | __u8 tcpi_retransmits; | |
124 | __u8 tcpi_probes; | |
125 | __u8 tcpi_backoff; | |
126 | __u8 tcpi_options; | |
127 | __u8 tcpi_snd_wscale : 4, tcpi_rcv_wscale : 4; | |
128 | ||
129 | __u32 tcpi_rto; | |
130 | __u32 tcpi_ato; | |
131 | __u32 tcpi_snd_mss; | |
132 | __u32 tcpi_rcv_mss; | |
133 | ||
134 | __u32 tcpi_unacked; | |
135 | __u32 tcpi_sacked; | |
136 | __u32 tcpi_lost; | |
137 | __u32 tcpi_retrans; | |
138 | __u32 tcpi_fackets; | |
139 | ||
140 | /* Times. */ | |
141 | __u32 tcpi_last_data_sent; | |
142 | __u32 tcpi_last_ack_sent; /* Not remembered, sorry. */ | |
143 | __u32 tcpi_last_data_recv; | |
144 | __u32 tcpi_last_ack_recv; | |
145 | ||
146 | /* Metrics. */ | |
147 | __u32 tcpi_pmtu; | |
148 | __u32 tcpi_rcv_ssthresh; | |
149 | __u32 tcpi_rtt; | |
150 | __u32 tcpi_rttvar; | |
151 | __u32 tcpi_snd_ssthresh; | |
152 | __u32 tcpi_snd_cwnd; | |
153 | __u32 tcpi_advmss; | |
154 | __u32 tcpi_reordering; | |
155 | ||
156 | __u32 tcpi_rcv_rtt; | |
157 | __u32 tcpi_rcv_space; | |
158 | ||
159 | __u32 tcpi_total_retrans; | |
160 | }; | |
161 | ||
cfb6eeb4 YH |
162 | /* for TCP_MD5SIG socket option */ |
163 | #define TCP_MD5SIG_MAXKEYLEN 80 | |
164 | ||
165 | struct tcp_md5sig { | |
166 | struct __kernel_sockaddr_storage tcpm_addr; /* address associated */ | |
167 | __u16 __tcpm_pad1; /* zero */ | |
168 | __u16 tcpm_keylen; /* key length */ | |
169 | __u32 __tcpm_pad2; /* zero */ | |
170 | __u8 tcpm_key[TCP_MD5SIG_MAXKEYLEN]; /* key (binary) */ | |
171 | }; | |
172 | ||
1da177e4 LT |
173 | #ifdef __KERNEL__ |
174 | ||
1da177e4 | 175 | #include <linux/skbuff.h> |
c8a553ad | 176 | #include <linux/dmaengine.h> |
1da177e4 | 177 | #include <net/sock.h> |
463c84b9 | 178 | #include <net/inet_connection_sock.h> |
8feaf0c0 | 179 | #include <net/inet_timewait_sock.h> |
1da177e4 | 180 | |
aa8223c7 ACM |
181 | static inline struct tcphdr *tcp_hdr(const struct sk_buff *skb) |
182 | { | |
9c70220b | 183 | return (struct tcphdr *)skb_transport_header(skb); |
aa8223c7 ACM |
184 | } |
185 | ||
ab6a5bb6 ACM |
186 | static inline unsigned int tcp_hdrlen(const struct sk_buff *skb) |
187 | { | |
aa8223c7 | 188 | return tcp_hdr(skb)->doff * 4; |
ab6a5bb6 ACM |
189 | } |
190 | ||
191 | static inline unsigned int tcp_optlen(const struct sk_buff *skb) | |
192 | { | |
aa8223c7 | 193 | return (tcp_hdr(skb)->doff - 5) * 4; |
ab6a5bb6 ACM |
194 | } |
195 | ||
1da177e4 | 196 | /* This defines a selective acknowledgement block. */ |
269bd27e AV |
197 | struct tcp_sack_block_wire { |
198 | __be32 start_seq; | |
199 | __be32 end_seq; | |
200 | }; | |
201 | ||
1da177e4 | 202 | struct tcp_sack_block { |
3a137d20 ACM |
203 | u32 start_seq; |
204 | u32 end_seq; | |
1da177e4 LT |
205 | }; |
206 | ||
1da177e4 LT |
207 | struct tcp_options_received { |
208 | /* PAWS/RTTM data */ | |
209 | long ts_recent_stamp;/* Time we stored ts_recent (for aging) */ | |
3a137d20 ACM |
210 | u32 ts_recent; /* Time stamp to echo next */ |
211 | u32 rcv_tsval; /* Time stamp value */ | |
212 | u32 rcv_tsecr; /* Time stamp echo reply */ | |
213 | u16 saw_tstamp : 1, /* Saw TIMESTAMP on last packet */ | |
1da177e4 LT |
214 | tstamp_ok : 1, /* TIMESTAMP seen on SYN packet */ |
215 | dsack : 1, /* D-SACK is scheduled */ | |
216 | wscale_ok : 1, /* Wscale seen on SYN packet */ | |
217 | sack_ok : 4, /* SACK seen on SYN packet */ | |
218 | snd_wscale : 4, /* Window scaling received from sender */ | |
219 | rcv_wscale : 4; /* Window scaling to send to receiver */ | |
220 | /* SACKs data */ | |
3a137d20 ACM |
221 | u8 eff_sacks; /* Size of SACK array to send with next packet */ |
222 | u8 num_sacks; /* Number of SACK blocks */ | |
223 | u16 user_mss; /* mss requested by user in ioctl */ | |
224 | u16 mss_clamp; /* Maximal mss, negotiated at connection setup */ | |
1da177e4 LT |
225 | }; |
226 | ||
2e6599cb | 227 | struct tcp_request_sock { |
cfb6eeb4 YH |
228 | struct inet_request_sock req; |
229 | #ifdef CONFIG_TCP_MD5SIG | |
230 | /* Only used by TCP MD5 Signature so far. */ | |
231 | struct tcp_request_sock_ops *af_specific; | |
232 | #endif | |
3a137d20 ACM |
233 | u32 rcv_isn; |
234 | u32 snt_isn; | |
2e6599cb ACM |
235 | }; |
236 | ||
60236fdd | 237 | static inline struct tcp_request_sock *tcp_rsk(const struct request_sock *req) |
2e6599cb ACM |
238 | { |
239 | return (struct tcp_request_sock *)req; | |
240 | } | |
241 | ||
ec3c0982 PM |
242 | struct tcp_deferred_accept_info { |
243 | struct sock *listen_sk; | |
244 | struct request_sock *request; | |
245 | }; | |
246 | ||
1da177e4 | 247 | struct tcp_sock { |
463c84b9 ACM |
248 | /* inet_connection_sock has to be the first member of tcp_sock */ |
249 | struct inet_connection_sock inet_conn; | |
2ff52f28 ACM |
250 | u16 tcp_header_len; /* Bytes of tcp header to send */ |
251 | u16 xmit_size_goal; /* Goal for segmenting output packets */ | |
1da177e4 LT |
252 | |
253 | /* | |
254 | * Header prediction flags | |
255 | * 0x5?10 << 16 + snd_wnd in net byte order | |
256 | */ | |
dddc93c0 | 257 | __be32 pred_flags; |
1da177e4 LT |
258 | |
259 | /* | |
260 | * RFC793 variables by their proper names. This means you can | |
261 | * read the code and the spec side by side (and laugh ...) | |
262 | * See RFC793 and RFC1122. The RFC writes these in capitals. | |
263 | */ | |
3a137d20 | 264 | u32 rcv_nxt; /* What we want to receive next */ |
54287cc1 ED |
265 | u32 copied_seq; /* Head of yet unread data */ |
266 | u32 rcv_wup; /* rcv_nxt on last window update sent */ | |
3a137d20 | 267 | u32 snd_nxt; /* Next sequence we send */ |
1da177e4 | 268 | |
3a137d20 ACM |
269 | u32 snd_una; /* First byte we want an ack for */ |
270 | u32 snd_sml; /* Last byte of the most recently transmitted small packet */ | |
271 | u32 rcv_tstamp; /* timestamp of last received ACK (for keepalives) */ | |
272 | u32 lsndtime; /* timestamp of last sent data packet (for restart window) */ | |
1da177e4 LT |
273 | |
274 | /* Data for direct copy to user */ | |
275 | struct { | |
276 | struct sk_buff_head prequeue; | |
277 | struct task_struct *task; | |
278 | struct iovec *iov; | |
279 | int memory; | |
280 | int len; | |
97fc2f08 CL |
281 | #ifdef CONFIG_NET_DMA |
282 | /* members for async copy */ | |
283 | struct dma_chan *dma_chan; | |
284 | int wakeup; | |
285 | struct dma_pinned_list *pinned_list; | |
286 | dma_cookie_t dma_cookie; | |
287 | #endif | |
1da177e4 LT |
288 | } ucopy; |
289 | ||
3a137d20 ACM |
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 mss_cache; /* Cached effective mss, not including SACKS */ | |
1da177e4 | 294 | |
3a137d20 ACM |
295 | u32 window_clamp; /* Maximal window to advertise */ |
296 | u32 rcv_ssthresh; /* Current window clamp */ | |
1da177e4 | 297 | |
3a137d20 ACM |
298 | u32 frto_highmark; /* snd_nxt when RTO occurred */ |
299 | u8 reordering; /* Packet reordering metric. */ | |
300 | u8 frto_counter; /* Number of new acks after RTO */ | |
301 | u8 nonagle; /* Disable Nagle algorithm? */ | |
302 | u8 keepalive_probes; /* num of allowed keep alive probes */ | |
1da177e4 LT |
303 | |
304 | /* RTT measurement */ | |
3a137d20 ACM |
305 | u32 srtt; /* smoothed round trip time << 3 */ |
306 | u32 mdev; /* medium deviation */ | |
307 | u32 mdev_max; /* maximal mdev for the last rtt period */ | |
308 | u32 rttvar; /* smoothed mdev_max */ | |
309 | u32 rtt_seq; /* sequence number to update rttvar */ | |
310 | ||
311 | u32 packets_out; /* Packets which are "in flight" */ | |
3a137d20 | 312 | u32 retrans_out; /* Retransmitted packets out */ |
1da177e4 LT |
313 | /* |
314 | * Options received (usually on last packet, some only on SYN packets). | |
315 | */ | |
1da177e4 LT |
316 | struct tcp_options_received rx_opt; |
317 | ||
318 | /* | |
319 | * Slow start and congestion control (see also Nagle, and Karn & Partridge) | |
320 | */ | |
3a137d20 ACM |
321 | u32 snd_ssthresh; /* Slow start size threshold */ |
322 | u32 snd_cwnd; /* Sending congestion window */ | |
f78a1b38 | 323 | u32 snd_cwnd_cnt; /* Linear increase counter */ |
e0ef57cc | 324 | u32 snd_cwnd_clamp; /* Do not allow snd_cwnd to grow above this */ |
3a137d20 ACM |
325 | u32 snd_cwnd_used; |
326 | u32 snd_cwnd_stamp; | |
1da177e4 | 327 | |
1da177e4 LT |
328 | struct sk_buff_head out_of_order_queue; /* Out of order segments go here */ |
329 | ||
3a137d20 | 330 | u32 rcv_wnd; /* Current receiver window */ |
3a137d20 ACM |
331 | u32 write_seq; /* Tail(+1) of data held in tcp send buffer */ |
332 | u32 pushed_seq; /* Last pushed seq, required to talk to windows */ | |
1da177e4 LT |
333 | |
334 | /* SACKs data */ | |
335 | struct tcp_sack_block duplicate_sack[1]; /* D-SACK block */ | |
336 | struct tcp_sack_block selective_acks[4]; /* The SACKS themselves*/ | |
337 | ||
fd6dad61 | 338 | struct tcp_sack_block recv_sack_cache[4]; |
6a438bbe | 339 | |
a47e5a98 IJ |
340 | struct sk_buff *highest_sack; /* highest skb with SACK received |
341 | * (validity guaranteed only if | |
342 | * sacked_out > 0) | |
343 | */ | |
d738cd8f | 344 | |
6a438bbe SH |
345 | /* from STCP, retrans queue hinting */ |
346 | struct sk_buff* lost_skb_hint; | |
347 | ||
348 | struct sk_buff *scoreboard_skb_hint; | |
349 | struct sk_buff *retransmit_skb_hint; | |
350 | struct sk_buff *forward_skb_hint; | |
6a438bbe | 351 | |
6a438bbe SH |
352 | int lost_cnt_hint; |
353 | int retransmit_cnt_hint; | |
6a438bbe | 354 | |
b08d6cb2 IJ |
355 | u32 lost_retrans_low; /* Sent seq after any rxmit (lowest) */ |
356 | ||
3a137d20 ACM |
357 | u16 advmss; /* Advertised MSS */ |
358 | u16 prior_ssthresh; /* ssthresh saved at recovery start */ | |
359 | u32 lost_out; /* Lost packets */ | |
360 | u32 sacked_out; /* SACK'd packets */ | |
361 | u32 fackets_out; /* FACK'd packets */ | |
362 | u32 high_seq; /* snd_nxt at onset of congestion */ | |
1da177e4 | 363 | |
3a137d20 | 364 | u32 retrans_stamp; /* Timestamp of the last retransmit, |
1da177e4 LT |
365 | * also used in SYN-SENT to remember stamp of |
366 | * the first SYN. */ | |
3a137d20 | 367 | u32 undo_marker; /* tracking retrans started here. */ |
1da177e4 | 368 | int undo_retrans; /* number of undoable retransmissions. */ |
3a137d20 ACM |
369 | u32 urg_seq; /* Seq of received urgent pointer */ |
370 | u16 urg_data; /* Saved octet of OOB data and control flags */ | |
371 | u8 urg_mode; /* In urgent mode */ | |
372 | u8 ecn_flags; /* ECN status bits. */ | |
373 | u32 snd_up; /* Urgent pointer */ | |
1da177e4 | 374 | |
3a137d20 ACM |
375 | u32 total_retrans; /* Total retransmits for entire connection */ |
376 | u32 bytes_acked; /* Appropriate Byte Counting - RFC3465 */ | |
1da177e4 | 377 | |
1da177e4 LT |
378 | unsigned int keepalive_time; /* time before keep alive takes place */ |
379 | unsigned int keepalive_intvl; /* time interval between keep alive probes */ | |
380 | int linger2; | |
381 | ||
ec3c0982 PM |
382 | struct tcp_deferred_accept_info defer_tcp_accept; |
383 | ||
1da177e4 LT |
384 | unsigned long last_synq_overflow; |
385 | ||
3a137d20 | 386 | u32 tso_deferred; |
ae8064ac | 387 | |
1da177e4 LT |
388 | /* Receiver side RTT estimation */ |
389 | struct { | |
3a137d20 ACM |
390 | u32 rtt; |
391 | u32 seq; | |
392 | u32 time; | |
1da177e4 LT |
393 | } rcv_rtt_est; |
394 | ||
395 | /* Receiver queue space */ | |
396 | struct { | |
397 | int space; | |
3a137d20 ACM |
398 | u32 seq; |
399 | u32 time; | |
1da177e4 | 400 | } rcvq_space; |
0e7b1368 JH |
401 | |
402 | /* TCP-specific MTU probe information. */ | |
403 | struct { | |
3a137d20 ACM |
404 | u32 probe_seq_start; |
405 | u32 probe_seq_end; | |
0e7b1368 | 406 | } mtu_probe; |
cfb6eeb4 YH |
407 | |
408 | #ifdef CONFIG_TCP_MD5SIG | |
409 | /* TCP AF-Specific parts; only used by MD5 Signature support so far */ | |
410 | struct tcp_sock_af_ops *af_specific; | |
411 | ||
412 | /* TCP MD5 Signagure Option information */ | |
413 | struct tcp_md5sig_info *md5sig_info; | |
414 | #endif | |
1da177e4 LT |
415 | }; |
416 | ||
417 | static inline struct tcp_sock *tcp_sk(const struct sock *sk) | |
418 | { | |
419 | return (struct tcp_sock *)sk; | |
420 | } | |
421 | ||
8feaf0c0 ACM |
422 | struct tcp_timewait_sock { |
423 | struct inet_timewait_sock tw_sk; | |
3a137d20 ACM |
424 | u32 tw_rcv_nxt; |
425 | u32 tw_snd_nxt; | |
426 | u32 tw_rcv_wnd; | |
427 | u32 tw_ts_recent; | |
8feaf0c0 | 428 | long tw_ts_recent_stamp; |
cfb6eeb4 | 429 | #ifdef CONFIG_TCP_MD5SIG |
3a137d20 ACM |
430 | u16 tw_md5_keylen; |
431 | u8 tw_md5_key[TCP_MD5SIG_MAXKEYLEN]; | |
cfb6eeb4 | 432 | #endif |
8feaf0c0 ACM |
433 | }; |
434 | ||
435 | static inline struct tcp_timewait_sock *tcp_twsk(const struct sock *sk) | |
436 | { | |
437 | return (struct tcp_timewait_sock *)sk; | |
438 | } | |
439 | ||
1da177e4 LT |
440 | #endif |
441 | ||
442 | #endif /* _LINUX_TCP_H */ |