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17#ifndef _LINUX_TCP_H
18#define _LINUX_TCP_H
19
20
21#include <linux/skbuff.h>
22#include <net/sock.h>
23#include <net/inet_connection_sock.h>
24#include <net/inet_timewait_sock.h>
25#include <uapi/linux/tcp.h>
26
27static inline struct tcphdr *tcp_hdr(const struct sk_buff *skb)
28{
29 return (struct tcphdr *)skb_transport_header(skb);
30}
31
32static inline unsigned int tcp_hdrlen(const struct sk_buff *skb)
33{
34 return tcp_hdr(skb)->doff * 4;
35}
36
37static inline struct tcphdr *inner_tcp_hdr(const struct sk_buff *skb)
38{
39 return (struct tcphdr *)skb_inner_transport_header(skb);
40}
41
42static inline unsigned int inner_tcp_hdrlen(const struct sk_buff *skb)
43{
44 return inner_tcp_hdr(skb)->doff * 4;
45}
46
47static inline unsigned int tcp_optlen(const struct sk_buff *skb)
48{
49 return (tcp_hdr(skb)->doff - 5) * 4;
50}
51
52
53#define TCP_FASTOPEN_COOKIE_MIN 4
54#define TCP_FASTOPEN_COOKIE_MAX 16
55#define TCP_FASTOPEN_COOKIE_SIZE 8
56
57
58struct tcp_fastopen_cookie {
59 s8 len;
60 u8 val[TCP_FASTOPEN_COOKIE_MAX];
61 bool exp;
62};
63
64
65struct tcp_sack_block_wire {
66 __be32 start_seq;
67 __be32 end_seq;
68};
69
70struct tcp_sack_block {
71 u32 start_seq;
72 u32 end_seq;
73};
74
75
76#define TCP_SACK_SEEN (1 << 0)
77#define TCP_FACK_ENABLED (1 << 1)
78#define TCP_DSACK_SEEN (1 << 2)
79
80struct tcp_options_received {
81
82 long ts_recent_stamp;
83 u32 ts_recent;
84 u32 rcv_tsval;
85 u32 rcv_tsecr;
86 u16 saw_tstamp : 1,
87 tstamp_ok : 1,
88 dsack : 1,
89 wscale_ok : 1,
90 sack_ok : 4,
91 snd_wscale : 4,
92 rcv_wscale : 4;
93 u8 num_sacks;
94 u16 user_mss;
95 u16 mss_clamp;
96};
97
98static inline void tcp_clear_options(struct tcp_options_received *rx_opt)
99{
100 rx_opt->tstamp_ok = rx_opt->sack_ok = 0;
101 rx_opt->wscale_ok = rx_opt->snd_wscale = 0;
102}
103
104
105
106
107
108#define TCP_NUM_SACKS 4
109
110struct tcp_request_sock_ops;
111
112struct tcp_request_sock {
113 struct inet_request_sock req;
114 const struct tcp_request_sock_ops *af_specific;
115 bool tfo_listener;
116 u32 rcv_isn;
117 u32 snt_isn;
118 u32 snt_synack;
119 u32 last_oow_ack_time;
120 u32 rcv_nxt;
121
122
123
124};
125
126static inline struct tcp_request_sock *tcp_rsk(const struct request_sock *req)
127{
128 return (struct tcp_request_sock *)req;
129}
130
131struct tcp_sock {
132
133 struct inet_connection_sock inet_conn;
134 u16 tcp_header_len;
135 u16 gso_segs;
136
137
138
139
140
141 __be32 pred_flags;
142
143
144
145
146
147
148 u64 bytes_received;
149
150
151
152 u32 segs_in;
153
154
155 u32 rcv_nxt;
156 u32 copied_seq;
157 u32 rcv_wup;
158 u32 snd_nxt;
159 u32 segs_out;
160
161
162 u64 bytes_acked;
163
164
165
166 struct u64_stats_sync syncp;
167
168 u32 snd_una;
169 u32 snd_sml;
170 u32 rcv_tstamp;
171 u32 lsndtime;
172 u32 last_oow_ack_time;
173
174 u32 tsoffset;
175
176 struct list_head tsq_node;
177 unsigned long tsq_flags;
178
179
180 struct {
181 struct sk_buff_head prequeue;
182 struct task_struct *task;
183 struct msghdr *msg;
184 int memory;
185 int len;
186 } ucopy;
187
188 u32 snd_wl1;
189 u32 snd_wnd;
190 u32 max_window;
191 u32 mss_cache;
192
193 u32 window_clamp;
194 u32 rcv_ssthresh;
195
196 u16 advmss;
197 u8 unused;
198 u8 nonagle : 4,
199 thin_lto : 1,
200 thin_dupack : 1,
201 repair : 1,
202 frto : 1;
203 u8 repair_queue;
204 u8 do_early_retrans:1,
205 syn_data:1,
206 syn_fastopen:1,
207 syn_fastopen_exp:1,
208 syn_data_acked:1,
209 save_syn:1,
210 is_cwnd_limited:1;
211 u32 tlp_high_seq;
212
213
214 u32 srtt_us;
215 u32 mdev_us;
216 u32 mdev_max_us;
217 u32 rttvar_us;
218 u32 rtt_seq;
219
220 u32 packets_out;
221 u32 retrans_out;
222 u32 max_packets_out;
223 u32 max_packets_seq;
224
225 u16 urg_data;
226 u8 ecn_flags;
227 u8 keepalive_probes;
228 u32 reordering;
229 u32 snd_up;
230
231
232
233
234 struct tcp_options_received rx_opt;
235
236
237
238
239 u32 snd_ssthresh;
240 u32 snd_cwnd;
241 u32 snd_cwnd_cnt;
242 u32 snd_cwnd_clamp;
243 u32 snd_cwnd_used;
244 u32 snd_cwnd_stamp;
245 u32 prior_cwnd;
246 u32 prr_delivered;
247
248 u32 prr_out;
249
250 u32 rcv_wnd;
251 u32 write_seq;
252 u32 notsent_lowat;
253 u32 pushed_seq;
254 u32 lost_out;
255 u32 sacked_out;
256 u32 fackets_out;
257
258
259 struct sk_buff* lost_skb_hint;
260 struct sk_buff *retransmit_skb_hint;
261
262
263
264
265 struct sk_buff_head out_of_order_queue;
266
267
268 struct tcp_sack_block duplicate_sack[1];
269 struct tcp_sack_block selective_acks[4];
270
271 struct tcp_sack_block recv_sack_cache[4];
272
273 struct sk_buff *highest_sack;
274
275
276
277
278
279 int lost_cnt_hint;
280 u32 retransmit_high;
281
282 u32 lost_retrans_low;
283
284 u32 prior_ssthresh;
285 u32 high_seq;
286
287 u32 retrans_stamp;
288
289
290 u32 undo_marker;
291 int undo_retrans;
292 u32 total_retrans;
293
294 u32 urg_seq;
295 unsigned int keepalive_time;
296 unsigned int keepalive_intvl;
297
298 int linger2;
299
300
301 struct {
302 u32 rtt;
303 u32 seq;
304 u32 time;
305 } rcv_rtt_est;
306
307
308 struct {
309 int space;
310 u32 seq;
311 u32 time;
312 } rcvq_space;
313
314
315 struct {
316 u32 probe_seq_start;
317 u32 probe_seq_end;
318 } mtu_probe;
319 u32 mtu_info;
320
321
322
323#ifdef CONFIG_TCP_MD5SIG
324
325 const struct tcp_sock_af_ops *af_specific;
326
327
328 struct tcp_md5sig_info __rcu *md5sig_info;
329#endif
330
331
332 struct tcp_fastopen_request *fastopen_req;
333
334
335
336 struct request_sock *fastopen_rsk;
337 u32 *saved_syn;
338};
339
340enum tsq_flags {
341 TSQ_THROTTLED,
342 TSQ_QUEUED,
343 TCP_TSQ_DEFERRED,
344 TCP_WRITE_TIMER_DEFERRED,
345 TCP_DELACK_TIMER_DEFERRED,
346 TCP_MTU_REDUCED_DEFERRED,
347
348
349};
350
351static inline struct tcp_sock *tcp_sk(const struct sock *sk)
352{
353 return (struct tcp_sock *)sk;
354}
355
356struct tcp_timewait_sock {
357 struct inet_timewait_sock tw_sk;
358 u32 tw_rcv_nxt;
359 u32 tw_snd_nxt;
360 u32 tw_rcv_wnd;
361 u32 tw_ts_offset;
362 u32 tw_ts_recent;
363
364
365 u32 tw_last_oow_ack_time;
366
367 long tw_ts_recent_stamp;
368#ifdef CONFIG_TCP_MD5SIG
369 struct tcp_md5sig_key *tw_md5_key;
370#endif
371};
372
373static inline struct tcp_timewait_sock *tcp_twsk(const struct sock *sk)
374{
375 return (struct tcp_timewait_sock *)sk;
376}
377
378static inline bool tcp_passive_fastopen(const struct sock *sk)
379{
380 return (sk->sk_state == TCP_SYN_RECV &&
381 tcp_sk(sk)->fastopen_rsk != NULL);
382}
383
384extern void tcp_sock_destruct(struct sock *sk);
385
386static inline int fastopen_init_queue(struct sock *sk, int backlog)
387{
388 struct request_sock_queue *queue =
389 &inet_csk(sk)->icsk_accept_queue;
390
391 if (queue->fastopenq == NULL) {
392 queue->fastopenq = kzalloc(
393 sizeof(struct fastopen_queue),
394 sk->sk_allocation);
395 if (queue->fastopenq == NULL)
396 return -ENOMEM;
397
398 sk->sk_destruct = tcp_sock_destruct;
399 spin_lock_init(&queue->fastopenq->lock);
400 }
401 queue->fastopenq->max_qlen = backlog;
402 return 0;
403}
404
405static inline void tcp_saved_syn_free(struct tcp_sock *tp)
406{
407 kfree(tp->saved_syn);
408 tp->saved_syn = NULL;
409}
410
411#endif
412