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13#ifndef _LINUX_TCP_H
14#define _LINUX_TCP_H
15
16
17#include <linux/skbuff.h>
18#include <linux/win_minmax.h>
19#include <net/sock.h>
20#include <net/inet_connection_sock.h>
21#include <net/inet_timewait_sock.h>
22#include <uapi/linux/tcp.h>
23
24static inline struct tcphdr *tcp_hdr(const struct sk_buff *skb)
25{
26 return (struct tcphdr *)skb_transport_header(skb);
27}
28
29static inline unsigned int __tcp_hdrlen(const struct tcphdr *th)
30{
31 return th->doff * 4;
32}
33
34static inline unsigned int tcp_hdrlen(const struct sk_buff *skb)
35{
36 return __tcp_hdrlen(tcp_hdr(skb));
37}
38
39static inline struct tcphdr *inner_tcp_hdr(const struct sk_buff *skb)
40{
41 return (struct tcphdr *)skb_inner_transport_header(skb);
42}
43
44static inline unsigned int inner_tcp_hdrlen(const struct sk_buff *skb)
45{
46 return inner_tcp_hdr(skb)->doff * 4;
47}
48
49static inline unsigned int tcp_optlen(const struct sk_buff *skb)
50{
51 return (tcp_hdr(skb)->doff - 5) * 4;
52}
53
54
55#define TCP_FASTOPEN_COOKIE_MIN 4
56#define TCP_FASTOPEN_COOKIE_MAX 16
57#define TCP_FASTOPEN_COOKIE_SIZE 8
58
59
60struct tcp_fastopen_cookie {
61 union {
62 u8 val[TCP_FASTOPEN_COOKIE_MAX];
63#if IS_ENABLED(CONFIG_IPV6)
64 struct in6_addr addr;
65#endif
66 };
67 s8 len;
68 bool exp;
69};
70
71
72struct tcp_sack_block_wire {
73 __be32 start_seq;
74 __be32 end_seq;
75};
76
77struct tcp_sack_block {
78 u32 start_seq;
79 u32 end_seq;
80};
81
82
83#define TCP_SACK_SEEN (1 << 0)
84#define TCP_DSACK_SEEN (1 << 2)
85
86struct tcp_options_received {
87
88 int ts_recent_stamp;
89 u32 ts_recent;
90 u32 rcv_tsval;
91 u32 rcv_tsecr;
92 u16 saw_tstamp : 1,
93 tstamp_ok : 1,
94 dsack : 1,
95 wscale_ok : 1,
96 sack_ok : 3,
97 smc_ok : 1,
98 snd_wscale : 4,
99 rcv_wscale : 4;
100 u8 num_sacks;
101 u16 user_mss;
102 u16 mss_clamp;
103};
104
105static inline void tcp_clear_options(struct tcp_options_received *rx_opt)
106{
107 rx_opt->tstamp_ok = rx_opt->sack_ok = 0;
108 rx_opt->wscale_ok = rx_opt->snd_wscale = 0;
109#if IS_ENABLED(CONFIG_SMC)
110 rx_opt->smc_ok = 0;
111#endif
112}
113
114
115
116
117
118#define TCP_NUM_SACKS 4
119
120struct tcp_request_sock_ops;
121
122struct tcp_request_sock {
123 struct inet_request_sock req;
124 const struct tcp_request_sock_ops *af_specific;
125 u64 snt_synack;
126 bool tfo_listener;
127 u32 txhash;
128 u32 rcv_isn;
129 u32 snt_isn;
130 u32 ts_off;
131 u32 last_oow_ack_time;
132 u32 rcv_nxt;
133
134
135
136};
137
138static inline struct tcp_request_sock *tcp_rsk(const struct request_sock *req)
139{
140 return (struct tcp_request_sock *)req;
141}
142
143struct tcp_sock {
144
145 struct inet_connection_sock inet_conn;
146 u16 tcp_header_len;
147 u16 gso_segs;
148
149
150
151
152
153 __be32 pred_flags;
154
155
156
157
158
159
160 u64 bytes_received;
161
162
163
164 u32 segs_in;
165
166
167 u32 data_segs_in;
168
169
170 u32 rcv_nxt;
171 u32 copied_seq;
172 u32 rcv_wup;
173 u32 snd_nxt;
174 u32 segs_out;
175
176
177 u32 data_segs_out;
178
179
180 u64 bytes_sent;
181
182
183 u64 bytes_acked;
184
185
186
187 u32 dsack_dups;
188
189
190 u32 snd_una;
191 u32 snd_sml;
192 u32 rcv_tstamp;
193 u32 lsndtime;
194 u32 last_oow_ack_time;
195 u32 compressed_ack_rcv_nxt;
196
197 u32 tsoffset;
198
199 struct list_head tsq_node;
200 struct list_head tsorted_sent_queue;
201
202 u32 snd_wl1;
203 u32 snd_wnd;
204 u32 max_window;
205 u32 mss_cache;
206
207 u32 window_clamp;
208 u32 rcv_ssthresh;
209
210
211 struct tcp_rack {
212 u64 mstamp;
213 u32 rtt_us;
214 u32 end_seq;
215 u32 last_delivered;
216 u8 reo_wnd_steps;
217#define TCP_RACK_RECOVERY_THRESH 16
218 u8 reo_wnd_persist:5,
219 dsack_seen:1,
220 advanced:1;
221 } rack;
222 u16 advmss;
223 u8 compressed_ack;
224 u32 chrono_start;
225 u32 chrono_stat[3];
226 u8 chrono_type:2,
227 rate_app_limited:1,
228 fastopen_connect:1,
229 fastopen_no_cookie:1,
230 is_sack_reneg:1,
231 unused:2;
232 u8 nonagle : 4,
233 thin_lto : 1,
234 recvmsg_inq : 1,
235 repair : 1,
236 frto : 1;
237 u8 repair_queue;
238 u8 syn_data:1,
239 syn_fastopen:1,
240 syn_fastopen_exp:1,
241 syn_fastopen_ch:1,
242 syn_data_acked:1,
243 save_syn:1,
244 is_cwnd_limited:1,
245 syn_smc:1;
246 u32 tlp_high_seq;
247
248 u64 tcp_wstamp_ns;
249 u64 tcp_clock_cache;
250
251
252 u64 tcp_mstamp;
253 u32 srtt_us;
254 u32 mdev_us;
255 u32 mdev_max_us;
256 u32 rttvar_us;
257 u32 rtt_seq;
258 struct minmax rtt_min;
259
260 u32 packets_out;
261 u32 retrans_out;
262 u32 max_packets_out;
263 u32 max_packets_seq;
264
265 u16 urg_data;
266 u8 ecn_flags;
267 u8 keepalive_probes;
268 u32 reordering;
269 u32 reord_seen;
270 u32 snd_up;
271
272
273
274
275 struct tcp_options_received rx_opt;
276
277
278
279
280 u32 snd_ssthresh;
281 u32 snd_cwnd;
282 u32 snd_cwnd_cnt;
283 u32 snd_cwnd_clamp;
284 u32 snd_cwnd_used;
285 u32 snd_cwnd_stamp;
286 u32 prior_cwnd;
287 u32 prr_delivered;
288
289 u32 prr_out;
290 u32 delivered;
291 u32 delivered_ce;
292 u32 lost;
293 u32 app_limited;
294 u64 first_tx_mstamp;
295 u64 delivered_mstamp;
296 u32 rate_delivered;
297 u32 rate_interval_us;
298
299 u32 rcv_wnd;
300 u32 write_seq;
301 u32 notsent_lowat;
302 u32 pushed_seq;
303 u32 lost_out;
304 u32 sacked_out;
305
306 struct hrtimer pacing_timer;
307 struct hrtimer compressed_ack_timer;
308
309
310 struct sk_buff* lost_skb_hint;
311 struct sk_buff *retransmit_skb_hint;
312
313
314 struct rb_root out_of_order_queue;
315 struct sk_buff *ooo_last_skb;
316
317
318 struct tcp_sack_block duplicate_sack[1];
319 struct tcp_sack_block selective_acks[4];
320
321 struct tcp_sack_block recv_sack_cache[4];
322
323 struct sk_buff *highest_sack;
324
325
326
327
328
329 int lost_cnt_hint;
330
331 u32 prior_ssthresh;
332 u32 high_seq;
333
334 u32 retrans_stamp;
335
336
337 u32 undo_marker;
338 int undo_retrans;
339 u64 bytes_retrans;
340
341
342 u32 total_retrans;
343
344 u32 urg_seq;
345 unsigned int keepalive_time;
346 unsigned int keepalive_intvl;
347
348 int linger2;
349
350
351
352#ifdef CONFIG_BPF
353 u8 bpf_sock_ops_cb_flags;
354
355
356#define BPF_SOCK_OPS_TEST_FLAG(TP, ARG) (TP->bpf_sock_ops_cb_flags & ARG)
357#else
358#define BPF_SOCK_OPS_TEST_FLAG(TP, ARG) 0
359#endif
360
361
362 u32 rcv_rtt_last_tsecr;
363 struct {
364 u32 rtt_us;
365 u32 seq;
366 u64 time;
367 } rcv_rtt_est;
368
369
370 struct {
371 u32 space;
372 u32 seq;
373 u64 time;
374 } rcvq_space;
375
376
377 struct {
378 u32 probe_seq_start;
379 u32 probe_seq_end;
380 } mtu_probe;
381 u32 mtu_info;
382
383
384
385#ifdef CONFIG_TCP_MD5SIG
386
387 const struct tcp_sock_af_ops *af_specific;
388
389
390 struct tcp_md5sig_info __rcu *md5sig_info;
391#endif
392
393
394 struct tcp_fastopen_request *fastopen_req;
395
396
397
398 struct request_sock *fastopen_rsk;
399 u32 *saved_syn;
400};
401
402enum tsq_enum {
403 TSQ_THROTTLED,
404 TSQ_QUEUED,
405 TCP_TSQ_DEFERRED,
406 TCP_WRITE_TIMER_DEFERRED,
407 TCP_DELACK_TIMER_DEFERRED,
408 TCP_MTU_REDUCED_DEFERRED,
409
410
411};
412
413enum tsq_flags {
414 TSQF_THROTTLED = (1UL << TSQ_THROTTLED),
415 TSQF_QUEUED = (1UL << TSQ_QUEUED),
416 TCPF_TSQ_DEFERRED = (1UL << TCP_TSQ_DEFERRED),
417 TCPF_WRITE_TIMER_DEFERRED = (1UL << TCP_WRITE_TIMER_DEFERRED),
418 TCPF_DELACK_TIMER_DEFERRED = (1UL << TCP_DELACK_TIMER_DEFERRED),
419 TCPF_MTU_REDUCED_DEFERRED = (1UL << TCP_MTU_REDUCED_DEFERRED),
420};
421
422static inline struct tcp_sock *tcp_sk(const struct sock *sk)
423{
424 return (struct tcp_sock *)sk;
425}
426
427struct tcp_timewait_sock {
428 struct inet_timewait_sock tw_sk;
429#define tw_rcv_nxt tw_sk.__tw_common.skc_tw_rcv_nxt
430#define tw_snd_nxt tw_sk.__tw_common.skc_tw_snd_nxt
431 u32 tw_rcv_wnd;
432 u32 tw_ts_offset;
433 u32 tw_ts_recent;
434
435
436 u32 tw_last_oow_ack_time;
437
438 int tw_ts_recent_stamp;
439#ifdef CONFIG_TCP_MD5SIG
440 struct tcp_md5sig_key *tw_md5_key;
441#endif
442};
443
444static inline struct tcp_timewait_sock *tcp_twsk(const struct sock *sk)
445{
446 return (struct tcp_timewait_sock *)sk;
447}
448
449static inline bool tcp_passive_fastopen(const struct sock *sk)
450{
451 return (sk->sk_state == TCP_SYN_RECV &&
452 tcp_sk(sk)->fastopen_rsk != NULL);
453}
454
455static inline void fastopen_queue_tune(struct sock *sk, int backlog)
456{
457 struct request_sock_queue *queue = &inet_csk(sk)->icsk_accept_queue;
458 int somaxconn = READ_ONCE(sock_net(sk)->core.sysctl_somaxconn);
459
460 queue->fastopenq.max_qlen = min_t(unsigned int, backlog, somaxconn);
461}
462
463static inline void tcp_move_syn(struct tcp_sock *tp,
464 struct request_sock *req)
465{
466 tp->saved_syn = req->saved_syn;
467 req->saved_syn = NULL;
468}
469
470static inline void tcp_saved_syn_free(struct tcp_sock *tp)
471{
472 kfree(tp->saved_syn);
473 tp->saved_syn = NULL;
474}
475
476struct sk_buff *tcp_get_timestamping_opt_stats(const struct sock *sk);
477
478static inline u16 tcp_mss_clamp(const struct tcp_sock *tp, u16 mss)
479{
480
481
482
483 u16 user_mss = READ_ONCE(tp->rx_opt.user_mss);
484
485 return (user_mss && user_mss < mss) ? user_mss : mss;
486}
487
488int tcp_skb_shift(struct sk_buff *to, struct sk_buff *from, int pcount,
489 int shiftlen);
490
491#endif
492