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 | ||
1da177e4 | 20 | |
1da177e4 | 21 | #include <linux/skbuff.h> |
64033892 | 22 | #include <linux/win_minmax.h> |
1da177e4 | 23 | #include <net/sock.h> |
463c84b9 | 24 | #include <net/inet_connection_sock.h> |
8feaf0c0 | 25 | #include <net/inet_timewait_sock.h> |
607ca46e | 26 | #include <uapi/linux/tcp.h> |
1da177e4 | 27 | |
aa8223c7 ACM |
28 | static inline struct tcphdr *tcp_hdr(const struct sk_buff *skb) |
29 | { | |
9c70220b | 30 | return (struct tcphdr *)skb_transport_header(skb); |
aa8223c7 ACM |
31 | } |
32 | ||
d9b3fca2 CG |
33 | static inline unsigned int __tcp_hdrlen(const struct tcphdr *th) |
34 | { | |
35 | return th->doff * 4; | |
36 | } | |
37 | ||
ab6a5bb6 ACM |
38 | static inline unsigned int tcp_hdrlen(const struct sk_buff *skb) |
39 | { | |
d9b3fca2 | 40 | return __tcp_hdrlen(tcp_hdr(skb)); |
ab6a5bb6 ACM |
41 | } |
42 | ||
6a674e9c JG |
43 | static inline struct tcphdr *inner_tcp_hdr(const struct sk_buff *skb) |
44 | { | |
45 | return (struct tcphdr *)skb_inner_transport_header(skb); | |
46 | } | |
47 | ||
48 | static inline unsigned int inner_tcp_hdrlen(const struct sk_buff *skb) | |
49 | { | |
50 | return inner_tcp_hdr(skb)->doff * 4; | |
51 | } | |
52 | ||
ab6a5bb6 ACM |
53 | static inline unsigned int tcp_optlen(const struct sk_buff *skb) |
54 | { | |
aa8223c7 | 55 | return (tcp_hdr(skb)->doff - 5) * 4; |
ab6a5bb6 ACM |
56 | } |
57 | ||
2100c8d2 YC |
58 | /* TCP Fast Open */ |
59 | #define TCP_FASTOPEN_COOKIE_MIN 4 /* Min Fast Open Cookie size in bytes */ | |
60 | #define TCP_FASTOPEN_COOKIE_MAX 16 /* Max Fast Open Cookie size in bytes */ | |
10467163 | 61 | #define TCP_FASTOPEN_COOKIE_SIZE 8 /* the size employed by this impl. */ |
2100c8d2 YC |
62 | |
63 | /* TCP Fast Open Cookie as stored in memory */ | |
64 | struct tcp_fastopen_cookie { | |
003c9410 SN |
65 | union { |
66 | u8 val[TCP_FASTOPEN_COOKIE_MAX]; | |
67 | #if IS_ENABLED(CONFIG_IPV6) | |
68 | struct in6_addr addr; | |
69 | #endif | |
70 | }; | |
2100c8d2 | 71 | s8 len; |
7f9b838b | 72 | bool exp; /* In RFC6994 experimental option format */ |
2100c8d2 YC |
73 | }; |
74 | ||
1da177e4 | 75 | /* This defines a selective acknowledgement block. */ |
269bd27e AV |
76 | struct tcp_sack_block_wire { |
77 | __be32 start_seq; | |
78 | __be32 end_seq; | |
79 | }; | |
80 | ||
1da177e4 | 81 | struct tcp_sack_block { |
3a137d20 ACM |
82 | u32 start_seq; |
83 | u32 end_seq; | |
1da177e4 LT |
84 | }; |
85 | ||
ab56222a VS |
86 | /*These are used to set the sack_ok field in struct tcp_options_received */ |
87 | #define TCP_SACK_SEEN (1 << 0) /*1 = peer is SACK capable, */ | |
88 | #define TCP_FACK_ENABLED (1 << 1) /*1 = FACK is enabled locally*/ | |
89 | #define TCP_DSACK_SEEN (1 << 2) /*1 = DSACK was received from peer*/ | |
90 | ||
1da177e4 LT |
91 | struct tcp_options_received { |
92 | /* PAWS/RTTM data */ | |
93 | long ts_recent_stamp;/* Time we stored ts_recent (for aging) */ | |
3a137d20 ACM |
94 | u32 ts_recent; /* Time stamp to echo next */ |
95 | u32 rcv_tsval; /* Time stamp value */ | |
96 | u32 rcv_tsecr; /* Time stamp echo reply */ | |
97 | u16 saw_tstamp : 1, /* Saw TIMESTAMP on last packet */ | |
1da177e4 LT |
98 | tstamp_ok : 1, /* TIMESTAMP seen on SYN packet */ |
99 | dsack : 1, /* D-SACK is scheduled */ | |
100 | wscale_ok : 1, /* Wscale seen on SYN packet */ | |
101 | sack_ok : 4, /* SACK seen on SYN packet */ | |
102 | snd_wscale : 4, /* Window scaling received from sender */ | |
103 | rcv_wscale : 4; /* Window scaling to send to receiver */ | |
3a137d20 | 104 | u8 num_sacks; /* Number of SACK blocks */ |
435cf559 | 105 | u16 user_mss; /* mss requested by user in ioctl */ |
3a137d20 | 106 | u16 mss_clamp; /* Maximal mss, negotiated at connection setup */ |
1da177e4 LT |
107 | }; |
108 | ||
519855c5 WAS |
109 | static inline void tcp_clear_options(struct tcp_options_received *rx_opt) |
110 | { | |
435cf559 WAS |
111 | rx_opt->tstamp_ok = rx_opt->sack_ok = 0; |
112 | rx_opt->wscale_ok = rx_opt->snd_wscale = 0; | |
519855c5 WAS |
113 | } |
114 | ||
4389dded | 115 | /* This is the max number of SACKS that we'll generate and process. It's safe |
435cf559 | 116 | * to increase this, although since: |
4389dded AL |
117 | * size = TCPOLEN_SACK_BASE_ALIGNED (4) + n * TCPOLEN_SACK_PERBLOCK (8) |
118 | * only four options will fit in a standard TCP header */ | |
119 | #define TCP_NUM_SACKS 4 | |
120 | ||
435cf559 WAS |
121 | struct tcp_request_sock_ops; |
122 | ||
2e6599cb | 123 | struct tcp_request_sock { |
cfb6eeb4 | 124 | struct inet_request_sock req; |
b2e4b3de | 125 | const struct tcp_request_sock_ops *af_specific; |
9a568de4 | 126 | u64 snt_synack; /* first SYNACK sent time */ |
9439ce00 | 127 | bool tfo_listener; |
58d607d3 | 128 | u32 txhash; |
435cf559 WAS |
129 | u32 rcv_isn; |
130 | u32 snt_isn; | |
95a22cae | 131 | u32 ts_off; |
a9b2c06d | 132 | u32 last_oow_ack_time; /* last SYNACK */ |
10467163 JC |
133 | u32 rcv_nxt; /* the ack # by SYNACK. For |
134 | * FastOpen it's the seq# | |
135 | * after data-in-SYN. | |
136 | */ | |
2e6599cb ACM |
137 | }; |
138 | ||
60236fdd | 139 | static inline struct tcp_request_sock *tcp_rsk(const struct request_sock *req) |
2e6599cb ACM |
140 | { |
141 | return (struct tcp_request_sock *)req; | |
142 | } | |
143 | ||
1da177e4 | 144 | struct tcp_sock { |
463c84b9 ACM |
145 | /* inet_connection_sock has to be the first member of tcp_sock */ |
146 | struct inet_connection_sock inet_conn; | |
2ff52f28 | 147 | u16 tcp_header_len; /* Bytes of tcp header to send */ |
605ad7f1 | 148 | u16 gso_segs; /* Max number of segs per GSO packet */ |
1da177e4 | 149 | |
31770e34 FW |
150 | /* |
151 | * Header prediction flags | |
152 | * 0x5?10 << 16 + snd_wnd in net byte order | |
153 | */ | |
154 | __be32 pred_flags; | |
155 | ||
1da177e4 LT |
156 | /* |
157 | * RFC793 variables by their proper names. This means you can | |
158 | * read the code and the spec side by side (and laugh ...) | |
159 | * See RFC793 and RFC1122. The RFC writes these in capitals. | |
160 | */ | |
bdd1f9ed ED |
161 | u64 bytes_received; /* RFC4898 tcpEStatsAppHCThruOctetsReceived |
162 | * sum(delta(rcv_nxt)), or how many bytes | |
163 | * were acked. | |
164 | */ | |
2efd055c MRL |
165 | u32 segs_in; /* RFC4898 tcpEStatsPerfSegsIn |
166 | * total number of segments in. | |
167 | */ | |
a44d6eac MKL |
168 | u32 data_segs_in; /* RFC4898 tcpEStatsPerfDataSegsIn |
169 | * total number of data segments in. | |
170 | */ | |
3a137d20 | 171 | u32 rcv_nxt; /* What we want to receive next */ |
54287cc1 ED |
172 | u32 copied_seq; /* Head of yet unread data */ |
173 | u32 rcv_wup; /* rcv_nxt on last window update sent */ | |
3a137d20 | 174 | u32 snd_nxt; /* Next sequence we send */ |
2efd055c MRL |
175 | u32 segs_out; /* RFC4898 tcpEStatsPerfSegsOut |
176 | * The total number of segments sent. | |
177 | */ | |
a44d6eac MKL |
178 | u32 data_segs_out; /* RFC4898 tcpEStatsPerfDataSegsOut |
179 | * total number of data segments sent. | |
180 | */ | |
0df48c26 ED |
181 | u64 bytes_acked; /* RFC4898 tcpEStatsAppHCThruOctetsAcked |
182 | * sum(delta(snd_una)), or how many bytes | |
183 | * were acked. | |
184 | */ | |
3a137d20 ACM |
185 | u32 snd_una; /* First byte we want an ack for */ |
186 | u32 snd_sml; /* Last byte of the most recently transmitted small packet */ | |
187 | u32 rcv_tstamp; /* timestamp of last received ACK (for keepalives) */ | |
188 | u32 lsndtime; /* timestamp of last sent data packet (for restart window) */ | |
f2b2c582 | 189 | u32 last_oow_ack_time; /* timestamp of last out-of-window ACK */ |
1da177e4 | 190 | |
ceaa1fef AV |
191 | u32 tsoffset; /* timestamp offset */ |
192 | ||
46d3ceab | 193 | struct list_head tsq_node; /* anchor in tsq_tasklet.head list */ |
46d3ceab | 194 | |
3a137d20 ACM |
195 | u32 snd_wl1; /* Sequence for window update */ |
196 | u32 snd_wnd; /* The window we expect to receive */ | |
197 | u32 max_window; /* Maximal window ever seen from peer */ | |
198 | u32 mss_cache; /* Cached effective mss, not including SACKS */ | |
1da177e4 | 199 | |
3a137d20 ACM |
200 | u32 window_clamp; /* Maximal window to advertise */ |
201 | u32 rcv_ssthresh; /* Current window clamp */ | |
1da177e4 | 202 | |
659a8ad5 YC |
203 | /* Information of the most recently (s)acked skb */ |
204 | struct tcp_rack { | |
9a568de4 | 205 | u64 mstamp; /* (Re)sent time of the skb */ |
deed7be7 | 206 | u32 rtt_us; /* Associated RTT */ |
1d0833df | 207 | u32 end_seq; /* Ending TCP sequence of the skb */ |
659a8ad5 YC |
208 | u8 advanced; /* mstamp advanced since last lost marking */ |
209 | u8 reord; /* reordering detected */ | |
210 | } rack; | |
b79eeeb9 | 211 | u16 advmss; /* Advertised MSS */ |
05b055e8 FY |
212 | u32 chrono_start; /* Start time in jiffies of a TCP chrono */ |
213 | u32 chrono_stat[3]; /* Time in jiffies for chrono_stat stats */ | |
214 | u8 chrono_type:2, /* current chronograph type */ | |
215 | rate_app_limited:1, /* rate_{delivered,interval_us} limited? */ | |
19f6d3f3 WW |
216 | fastopen_connect:1, /* FASTOPEN_CONNECT sockopt */ |
217 | unused:4; | |
36e31b0a AP |
218 | u8 nonagle : 4,/* Disable Nagle algorithm? */ |
219 | thin_lto : 1,/* Use linear timeouts for thin streams */ | |
4a7f6009 | 220 | unused1 : 1, |
e33099f9 YC |
221 | repair : 1, |
222 | frto : 1;/* F-RTO (RFC5682) activated in CA_Loss */ | |
ee995283 | 223 | u8 repair_queue; |
bec41a11 | 224 | u8 syn_data:1, /* SYN includes data */ |
6f73601e | 225 | syn_fastopen:1, /* SYN includes Fast Open option */ |
2646c831 | 226 | syn_fastopen_exp:1,/* SYN includes Fast Open exp. option */ |
cf1ef3f0 | 227 | syn_fastopen_ch:1, /* Active TFO re-enabling probe */ |
ca8a2263 | 228 | syn_data_acked:1,/* data in SYN is acked by SYN-ACK */ |
cd8ae852 | 229 | save_syn:1, /* Save headers of SYN packet */ |
ca8a2263 | 230 | is_cwnd_limited:1;/* forward progress limited by snd_cwnd? */ |
9b717a8d | 231 | u32 tlp_high_seq; /* snd_nxt at the time of TLP retransmit. */ |
1da177e4 LT |
232 | |
233 | /* RTT measurement */ | |
9a568de4 | 234 | u64 tcp_mstamp; /* most recent packet received/sent */ |
740b0f18 ED |
235 | u32 srtt_us; /* smoothed round trip time << 3 in usecs */ |
236 | u32 mdev_us; /* medium deviation */ | |
237 | u32 mdev_max_us; /* maximal mdev for the last rtt period */ | |
238 | u32 rttvar_us; /* smoothed mdev_max */ | |
3a137d20 | 239 | u32 rtt_seq; /* sequence number to update rttvar */ |
64033892 | 240 | struct minmax rtt_min; |
3a137d20 ACM |
241 | |
242 | u32 packets_out; /* Packets which are "in flight" */ | |
3a137d20 | 243 | u32 retrans_out; /* Retransmitted packets out */ |
ca8a2263 NC |
244 | u32 max_packets_out; /* max packets_out in last window */ |
245 | u32 max_packets_seq; /* right edge of max_packets_out flight */ | |
b79eeeb9 IJ |
246 | |
247 | u16 urg_data; /* Saved octet of OOB data and control flags */ | |
b79eeeb9 | 248 | u8 ecn_flags; /* ECN status bits. */ |
dca145ff ED |
249 | u8 keepalive_probes; /* num of allowed keep alive probes */ |
250 | u32 reordering; /* Packet reordering metric. */ | |
33f5f57e IJ |
251 | u32 snd_up; /* Urgent pointer */ |
252 | ||
1da177e4 LT |
253 | /* |
254 | * Options received (usually on last packet, some only on SYN packets). | |
255 | */ | |
1da177e4 LT |
256 | struct tcp_options_received rx_opt; |
257 | ||
258 | /* | |
259 | * Slow start and congestion control (see also Nagle, and Karn & Partridge) | |
260 | */ | |
3a137d20 ACM |
261 | u32 snd_ssthresh; /* Slow start size threshold */ |
262 | u32 snd_cwnd; /* Sending congestion window */ | |
f78a1b38 | 263 | u32 snd_cwnd_cnt; /* Linear increase counter */ |
e0ef57cc | 264 | u32 snd_cwnd_clamp; /* Do not allow snd_cwnd to grow above this */ |
3a137d20 ACM |
265 | u32 snd_cwnd_used; |
266 | u32 snd_cwnd_stamp; | |
4faf7839 | 267 | u32 prior_cwnd; /* cwnd right before starting loss recovery */ |
a262f0cd ND |
268 | u32 prr_delivered; /* Number of newly delivered packets to |
269 | * receiver in Recovery. */ | |
270 | u32 prr_out; /* Total number of pkts sent during Recovery. */ | |
ddf1af6f | 271 | u32 delivered; /* Total data packets delivered incl. rexmits */ |
0682e690 | 272 | u32 lost; /* Total data packets lost incl. rexmits */ |
d7722e85 | 273 | u32 app_limited; /* limited until "delivered" reaches this val */ |
9a568de4 ED |
274 | u64 first_tx_mstamp; /* start of window send phase */ |
275 | u64 delivered_mstamp; /* time we reached "delivered" */ | |
eb8329e0 YC |
276 | u32 rate_delivered; /* saved rate sample: packets delivered */ |
277 | u32 rate_interval_us; /* saved rate sample: time elapsed */ | |
1da177e4 | 278 | |
3a137d20 | 279 | u32 rcv_wnd; /* Current receiver window */ |
3a137d20 | 280 | u32 write_seq; /* Tail(+1) of data held in tcp send buffer */ |
c9bee3b7 | 281 | u32 notsent_lowat; /* TCP_NOTSENT_LOWAT */ |
3a137d20 | 282 | u32 pushed_seq; /* Last pushed seq, required to talk to windows */ |
b79eeeb9 IJ |
283 | u32 lost_out; /* Lost packets */ |
284 | u32 sacked_out; /* SACK'd packets */ | |
285 | u32 fackets_out; /* FACK'd packets */ | |
1da177e4 | 286 | |
218af599 ED |
287 | struct hrtimer pacing_timer; |
288 | ||
b79eeeb9 IJ |
289 | /* from STCP, retrans queue hinting */ |
290 | struct sk_buff* lost_skb_hint; | |
b79eeeb9 | 291 | struct sk_buff *retransmit_skb_hint; |
b79eeeb9 | 292 | |
9f5afeae YW |
293 | /* OOO segments go in this rbtree. Socket lock must be held. */ |
294 | struct rb_root out_of_order_queue; | |
295 | struct sk_buff *ooo_last_skb; /* cache rb_last(out_of_order_queue) */ | |
b79eeeb9 | 296 | |
c0a788c4 | 297 | /* SACKs data, these 2 need to be together (see tcp_options_write) */ |
1da177e4 LT |
298 | struct tcp_sack_block duplicate_sack[1]; /* D-SACK block */ |
299 | struct tcp_sack_block selective_acks[4]; /* The SACKS themselves*/ | |
300 | ||
fd6dad61 | 301 | struct tcp_sack_block recv_sack_cache[4]; |
6a438bbe | 302 | |
ecb97192 NC |
303 | struct sk_buff *highest_sack; /* skb just after the highest |
304 | * skb with SACKed bit set | |
a47e5a98 IJ |
305 | * (validity guaranteed only if |
306 | * sacked_out > 0) | |
307 | */ | |
d738cd8f | 308 | |
6a438bbe | 309 | int lost_cnt_hint; |
6a438bbe | 310 | |
4b749440 | 311 | u32 prior_ssthresh; /* ssthresh saved at recovery start */ |
3a137d20 | 312 | u32 high_seq; /* snd_nxt at onset of congestion */ |
1da177e4 | 313 | |
3a137d20 | 314 | u32 retrans_stamp; /* Timestamp of the last retransmit, |
1da177e4 LT |
315 | * also used in SYN-SENT to remember stamp of |
316 | * the first SYN. */ | |
989e04c5 | 317 | u32 undo_marker; /* snd_una upon a new recovery episode. */ |
1da177e4 | 318 | int undo_retrans; /* number of undoable retransmissions. */ |
b79eeeb9 IJ |
319 | u32 total_retrans; /* Total retransmits for entire connection */ |
320 | ||
3a137d20 | 321 | u32 urg_seq; /* Seq of received urgent pointer */ |
1da177e4 LT |
322 | unsigned int keepalive_time; /* time before keep alive takes place */ |
323 | unsigned int keepalive_intvl; /* time interval between keep alive probes */ | |
1da177e4 | 324 | |
a0f82f64 | 325 | int linger2; |
1da177e4 LT |
326 | |
327 | /* Receiver side RTT estimation */ | |
328 | struct { | |
9a568de4 ED |
329 | u32 rtt_us; |
330 | u32 seq; | |
331 | u64 time; | |
1da177e4 LT |
332 | } rcv_rtt_est; |
333 | ||
334 | /* Receiver queue space */ | |
335 | struct { | |
9a568de4 ED |
336 | int space; |
337 | u32 seq; | |
338 | u64 time; | |
1da177e4 | 339 | } rcvq_space; |
0e7b1368 JH |
340 | |
341 | /* TCP-specific MTU probe information. */ | |
342 | struct { | |
3a137d20 ACM |
343 | u32 probe_seq_start; |
344 | u32 probe_seq_end; | |
0e7b1368 | 345 | } mtu_probe; |
563d34d0 ED |
346 | u32 mtu_info; /* We received an ICMP_FRAG_NEEDED / ICMPV6_PKT_TOOBIG |
347 | * while socket was owned by user. | |
348 | */ | |
cfb6eeb4 YH |
349 | |
350 | #ifdef CONFIG_TCP_MD5SIG | |
351 | /* TCP AF-Specific parts; only used by MD5 Signature support so far */ | |
b2e4b3de | 352 | const struct tcp_sock_af_ops *af_specific; |
cfb6eeb4 | 353 | |
b2e4b3de | 354 | /* TCP MD5 Signature Option information */ |
a8afca03 | 355 | struct tcp_md5sig_info __rcu *md5sig_info; |
cfb6eeb4 | 356 | #endif |
435cf559 | 357 | |
10467163 JC |
358 | /* TCP fastopen related information */ |
359 | struct tcp_fastopen_request *fastopen_req; | |
360 | /* fastopen_rsk points to request_sock that resulted in this big | |
361 | * socket. Used to retransmit SYNACKs etc. | |
362 | */ | |
363 | struct request_sock *fastopen_rsk; | |
cd8ae852 | 364 | u32 *saved_syn; |
1da177e4 LT |
365 | }; |
366 | ||
40fc3423 | 367 | enum tsq_enum { |
46d3ceab ED |
368 | TSQ_THROTTLED, |
369 | TSQ_QUEUED, | |
6f458dfb ED |
370 | TCP_TSQ_DEFERRED, /* tcp_tasklet_func() found socket was owned */ |
371 | TCP_WRITE_TIMER_DEFERRED, /* tcp_write_timer() found socket was owned */ | |
372 | TCP_DELACK_TIMER_DEFERRED, /* tcp_delack_timer() found socket was owned */ | |
563d34d0 ED |
373 | TCP_MTU_REDUCED_DEFERRED, /* tcp_v{4|6}_err() could not call |
374 | * tcp_v{4|6}_mtu_reduced() | |
375 | */ | |
46d3ceab ED |
376 | }; |
377 | ||
40fc3423 ED |
378 | enum tsq_flags { |
379 | TSQF_THROTTLED = (1UL << TSQ_THROTTLED), | |
380 | TSQF_QUEUED = (1UL << TSQ_QUEUED), | |
381 | TCPF_TSQ_DEFERRED = (1UL << TCP_TSQ_DEFERRED), | |
382 | TCPF_WRITE_TIMER_DEFERRED = (1UL << TCP_WRITE_TIMER_DEFERRED), | |
383 | TCPF_DELACK_TIMER_DEFERRED = (1UL << TCP_DELACK_TIMER_DEFERRED), | |
384 | TCPF_MTU_REDUCED_DEFERRED = (1UL << TCP_MTU_REDUCED_DEFERRED), | |
385 | }; | |
386 | ||
1da177e4 LT |
387 | static inline struct tcp_sock *tcp_sk(const struct sock *sk) |
388 | { | |
389 | return (struct tcp_sock *)sk; | |
390 | } | |
391 | ||
8feaf0c0 ACM |
392 | struct tcp_timewait_sock { |
393 | struct inet_timewait_sock tw_sk; | |
d475f090 ED |
394 | #define tw_rcv_nxt tw_sk.__tw_common.skc_tw_rcv_nxt |
395 | #define tw_snd_nxt tw_sk.__tw_common.skc_tw_snd_nxt | |
3a137d20 | 396 | u32 tw_rcv_wnd; |
ceaa1fef | 397 | u32 tw_ts_offset; |
3a137d20 | 398 | u32 tw_ts_recent; |
4fb17a60 NC |
399 | |
400 | /* The time we sent the last out-of-window ACK: */ | |
401 | u32 tw_last_oow_ack_time; | |
402 | ||
8feaf0c0 | 403 | long tw_ts_recent_stamp; |
cfb6eeb4 | 404 | #ifdef CONFIG_TCP_MD5SIG |
2397849b | 405 | struct tcp_md5sig_key *tw_md5_key; |
cfb6eeb4 | 406 | #endif |
8feaf0c0 ACM |
407 | }; |
408 | ||
409 | static inline struct tcp_timewait_sock *tcp_twsk(const struct sock *sk) | |
410 | { | |
411 | return (struct tcp_timewait_sock *)sk; | |
412 | } | |
413 | ||
10467163 JC |
414 | static inline bool tcp_passive_fastopen(const struct sock *sk) |
415 | { | |
416 | return (sk->sk_state == TCP_SYN_RECV && | |
417 | tcp_sk(sk)->fastopen_rsk != NULL); | |
418 | } | |
419 | ||
0536fcc0 | 420 | static inline void fastopen_queue_tune(struct sock *sk, int backlog) |
10467163 | 421 | { |
0536fcc0 | 422 | struct request_sock_queue *queue = &inet_csk(sk)->icsk_accept_queue; |
dbf650b6 | 423 | int somaxconn = READ_ONCE(sock_net(sk)->core.sysctl_somaxconn); |
0536fcc0 | 424 | |
dbf650b6 | 425 | queue->fastopenq.max_qlen = min_t(unsigned int, backlog, somaxconn); |
10467163 JC |
426 | } |
427 | ||
805c4bc0 ED |
428 | static inline void tcp_move_syn(struct tcp_sock *tp, |
429 | struct request_sock *req) | |
430 | { | |
431 | tp->saved_syn = req->saved_syn; | |
432 | req->saved_syn = NULL; | |
433 | } | |
434 | ||
cd8ae852 ED |
435 | static inline void tcp_saved_syn_free(struct tcp_sock *tp) |
436 | { | |
437 | kfree(tp->saved_syn); | |
438 | tp->saved_syn = NULL; | |
439 | } | |
440 | ||
1c885808 FY |
441 | struct sk_buff *tcp_get_timestamping_opt_stats(const struct sock *sk); |
442 | ||
3541f9e8 ED |
443 | static inline u16 tcp_mss_clamp(const struct tcp_sock *tp, u16 mss) |
444 | { | |
445 | /* We use READ_ONCE() here because socket might not be locked. | |
446 | * This happens for listeners. | |
447 | */ | |
448 | u16 user_mss = READ_ONCE(tp->rx_opt.user_mss); | |
449 | ||
450 | return (user_mss && user_mss < mss) ? user_mss : mss; | |
451 | } | |
1da177e4 | 452 | #endif /* _LINUX_TCP_H */ |