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-rw-r--r--include/linux/tcp.h253
1 files changed, 45 insertions, 208 deletions
diff --git a/include/linux/tcp.h b/include/linux/tcp.h
index eb125a4c30b3..8a7fc4be2d75 100644
--- a/include/linux/tcp.h
+++ b/include/linux/tcp.h
@@ -17,216 +17,13 @@
17#ifndef _LINUX_TCP_H 17#ifndef _LINUX_TCP_H
18#define _LINUX_TCP_H 18#define _LINUX_TCP_H
19 19
20#include <linux/types.h>
21#include <asm/byteorder.h>
22#include <linux/socket.h>
23
24struct tcphdr {
25 __be16 source;
26 __be16 dest;
27 __be32 seq;
28 __be32 ack_seq;
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
54 __be16 window;
55 __sum16 check;
56 __be16 urg_ptr;
57};
58
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 */
64union tcp_word_hdr {
65 struct tcphdr hdr;
66 __be32 words[5];
67};
68
69#define tcp_flag_word(tp) ( ((union tcp_word_hdr *)(tp))->words [3])
70
71enum {
72 TCP_FLAG_CWR = __constant_cpu_to_be32(0x00800000),
73 TCP_FLAG_ECE = __constant_cpu_to_be32(0x00400000),
74 TCP_FLAG_URG = __constant_cpu_to_be32(0x00200000),
75 TCP_FLAG_ACK = __constant_cpu_to_be32(0x00100000),
76 TCP_FLAG_PSH = __constant_cpu_to_be32(0x00080000),
77 TCP_FLAG_RST = __constant_cpu_to_be32(0x00040000),
78 TCP_FLAG_SYN = __constant_cpu_to_be32(0x00020000),
79 TCP_FLAG_FIN = __constant_cpu_to_be32(0x00010000),
80 TCP_RESERVED_BITS = __constant_cpu_to_be32(0x0F000000),
81 TCP_DATA_OFFSET = __constant_cpu_to_be32(0xF0000000)
82};
83
84/*
85 * TCP general constants
86 */
87#define TCP_MSS_DEFAULT 536U /* IPv4 (RFC1122, RFC2581) */
88#define TCP_MSS_DESIRED 1220U /* IPv6 (tunneled), EDNS0 (RFC3226) */
89
90/* TCP socket options */
91#define TCP_NODELAY 1 /* Turn off Nagle's algorithm. */
92#define TCP_MAXSEG 2 /* Limit MSS */
93#define TCP_CORK 3 /* Never send partially complete segments */
94#define TCP_KEEPIDLE 4 /* Start keeplives after this period */
95#define TCP_KEEPINTVL 5 /* Interval between keepalives */
96#define TCP_KEEPCNT 6 /* Number of keepalives before death */
97#define TCP_SYNCNT 7 /* Number of SYN retransmits */
98#define TCP_LINGER2 8 /* Life time of orphaned FIN-WAIT-2 state */
99#define TCP_DEFER_ACCEPT 9 /* Wake up listener only when data arrive */
100#define TCP_WINDOW_CLAMP 10 /* Bound advertised window */
101#define TCP_INFO 11 /* Information about this connection. */
102#define TCP_QUICKACK 12 /* Block/reenable quick acks */
103#define TCP_CONGESTION 13 /* Congestion control algorithm */
104#define TCP_MD5SIG 14 /* TCP MD5 Signature (RFC2385) */
105#define TCP_COOKIE_TRANSACTIONS 15 /* TCP Cookie Transactions */
106#define TCP_THIN_LINEAR_TIMEOUTS 16 /* Use linear timeouts for thin streams*/
107#define TCP_THIN_DUPACK 17 /* Fast retrans. after 1 dupack */
108#define TCP_USER_TIMEOUT 18 /* How long for loss retry before timeout */
109#define TCP_REPAIR 19 /* TCP sock is under repair right now */
110#define TCP_REPAIR_QUEUE 20
111#define TCP_QUEUE_SEQ 21
112#define TCP_REPAIR_OPTIONS 22
113
114struct tcp_repair_opt {
115 __u32 opt_code;
116 __u32 opt_val;
117};
118
119enum {
120 TCP_NO_QUEUE,
121 TCP_RECV_QUEUE,
122 TCP_SEND_QUEUE,
123 TCP_QUEUES_NR,
124};
125
126/* for TCP_INFO socket option */
127#define TCPI_OPT_TIMESTAMPS 1
128#define TCPI_OPT_SACK 2
129#define TCPI_OPT_WSCALE 4
130#define TCPI_OPT_ECN 8 /* ECN was negociated at TCP session init */
131#define TCPI_OPT_ECN_SEEN 16 /* we received at least one packet with ECT */
132
133enum tcp_ca_state {
134 TCP_CA_Open = 0,
135#define TCPF_CA_Open (1<<TCP_CA_Open)
136 TCP_CA_Disorder = 1,
137#define TCPF_CA_Disorder (1<<TCP_CA_Disorder)
138 TCP_CA_CWR = 2,
139#define TCPF_CA_CWR (1<<TCP_CA_CWR)
140 TCP_CA_Recovery = 3,
141#define TCPF_CA_Recovery (1<<TCP_CA_Recovery)
142 TCP_CA_Loss = 4
143#define TCPF_CA_Loss (1<<TCP_CA_Loss)
144};
145
146struct tcp_info {
147 __u8 tcpi_state;
148 __u8 tcpi_ca_state;
149 __u8 tcpi_retransmits;
150 __u8 tcpi_probes;
151 __u8 tcpi_backoff;
152 __u8 tcpi_options;
153 __u8 tcpi_snd_wscale : 4, tcpi_rcv_wscale : 4;
154
155 __u32 tcpi_rto;
156 __u32 tcpi_ato;
157 __u32 tcpi_snd_mss;
158 __u32 tcpi_rcv_mss;
159
160 __u32 tcpi_unacked;
161 __u32 tcpi_sacked;
162 __u32 tcpi_lost;
163 __u32 tcpi_retrans;
164 __u32 tcpi_fackets;
165
166 /* Times. */
167 __u32 tcpi_last_data_sent;
168 __u32 tcpi_last_ack_sent; /* Not remembered, sorry. */
169 __u32 tcpi_last_data_recv;
170 __u32 tcpi_last_ack_recv;
171
172 /* Metrics. */
173 __u32 tcpi_pmtu;
174 __u32 tcpi_rcv_ssthresh;
175 __u32 tcpi_rtt;
176 __u32 tcpi_rttvar;
177 __u32 tcpi_snd_ssthresh;
178 __u32 tcpi_snd_cwnd;
179 __u32 tcpi_advmss;
180 __u32 tcpi_reordering;
181
182 __u32 tcpi_rcv_rtt;
183 __u32 tcpi_rcv_space;
184
185 __u32 tcpi_total_retrans;
186};
187
188/* for TCP_MD5SIG socket option */
189#define TCP_MD5SIG_MAXKEYLEN 80
190
191struct tcp_md5sig {
192 struct __kernel_sockaddr_storage tcpm_addr; /* address associated */
193 __u16 __tcpm_pad1; /* zero */
194 __u16 tcpm_keylen; /* key length */
195 __u32 __tcpm_pad2; /* zero */
196 __u8 tcpm_key[TCP_MD5SIG_MAXKEYLEN]; /* key (binary) */
197};
198
199/* for TCP_COOKIE_TRANSACTIONS (TCPCT) socket option */
200#define TCP_COOKIE_MIN 8 /* 64-bits */
201#define TCP_COOKIE_MAX 16 /* 128-bits */
202#define TCP_COOKIE_PAIR_SIZE (2*TCP_COOKIE_MAX)
203
204/* Flags for both getsockopt and setsockopt */
205#define TCP_COOKIE_IN_ALWAYS (1 << 0) /* Discard SYN without cookie */
206#define TCP_COOKIE_OUT_NEVER (1 << 1) /* Prohibit outgoing cookies,
207 * supercedes everything. */
208
209/* Flags for getsockopt */
210#define TCP_S_DATA_IN (1 << 2) /* Was data received? */
211#define TCP_S_DATA_OUT (1 << 3) /* Was data sent? */
212
213/* TCP_COOKIE_TRANSACTIONS data */
214struct tcp_cookie_transactions {
215 __u16 tcpct_flags; /* see above */
216 __u8 __tcpct_pad1; /* zero */
217 __u8 tcpct_cookie_desired; /* bytes */
218 __u16 tcpct_s_data_desired; /* bytes of variable data */
219 __u16 tcpct_used; /* bytes in value */
220 __u8 tcpct_value[TCP_MSS_DEFAULT];
221};
222
223#ifdef __KERNEL__
224 20
225#include <linux/skbuff.h> 21#include <linux/skbuff.h>
226#include <linux/dmaengine.h> 22#include <linux/dmaengine.h>
227#include <net/sock.h> 23#include <net/sock.h>
228#include <net/inet_connection_sock.h> 24#include <net/inet_connection_sock.h>
229#include <net/inet_timewait_sock.h> 25#include <net/inet_timewait_sock.h>
26#include <uapi/linux/tcp.h>
230 27
231static inline struct tcphdr *tcp_hdr(const struct sk_buff *skb) 28static inline struct tcphdr *tcp_hdr(const struct sk_buff *skb)
232{ 29{
@@ -246,6 +43,7 @@ static inline unsigned int tcp_optlen(const struct sk_buff *skb)
246/* TCP Fast Open */ 43/* TCP Fast Open */
247#define TCP_FASTOPEN_COOKIE_MIN 4 /* Min Fast Open Cookie size in bytes */ 44#define TCP_FASTOPEN_COOKIE_MIN 4 /* Min Fast Open Cookie size in bytes */
248#define TCP_FASTOPEN_COOKIE_MAX 16 /* Max Fast Open Cookie size in bytes */ 45#define TCP_FASTOPEN_COOKIE_MAX 16 /* Max Fast Open Cookie size in bytes */
46#define TCP_FASTOPEN_COOKIE_SIZE 8 /* the size employed by this impl. */
249 47
250/* TCP Fast Open Cookie as stored in memory */ 48/* TCP Fast Open Cookie as stored in memory */
251struct tcp_fastopen_cookie { 49struct tcp_fastopen_cookie {
@@ -312,9 +110,14 @@ struct tcp_request_sock {
312 /* Only used by TCP MD5 Signature so far. */ 110 /* Only used by TCP MD5 Signature so far. */
313 const struct tcp_request_sock_ops *af_specific; 111 const struct tcp_request_sock_ops *af_specific;
314#endif 112#endif
113 struct sock *listener; /* needed for TFO */
315 u32 rcv_isn; 114 u32 rcv_isn;
316 u32 snt_isn; 115 u32 snt_isn;
317 u32 snt_synack; /* synack sent time */ 116 u32 snt_synack; /* synack sent time */
117 u32 rcv_nxt; /* the ack # by SYNACK. For
118 * FastOpen it's the seq#
119 * after data-in-SYN.
120 */
318}; 121};
319 122
320static inline struct tcp_request_sock *tcp_rsk(const struct request_sock *req) 123static inline struct tcp_request_sock *tcp_rsk(const struct request_sock *req)
@@ -505,14 +308,18 @@ struct tcp_sock {
505 struct tcp_md5sig_info __rcu *md5sig_info; 308 struct tcp_md5sig_info __rcu *md5sig_info;
506#endif 309#endif
507 310
508/* TCP fastopen related information */
509 struct tcp_fastopen_request *fastopen_req;
510
511 /* When the cookie options are generated and exchanged, then this 311 /* When the cookie options are generated and exchanged, then this
512 * object holds a reference to them (cookie_values->kref). Also 312 * object holds a reference to them (cookie_values->kref). Also
513 * contains related tcp_cookie_transactions fields. 313 * contains related tcp_cookie_transactions fields.
514 */ 314 */
515 struct tcp_cookie_values *cookie_values; 315 struct tcp_cookie_values *cookie_values;
316
317/* TCP fastopen related information */
318 struct tcp_fastopen_request *fastopen_req;
319 /* fastopen_rsk points to request_sock that resulted in this big
320 * socket. Used to retransmit SYNACKs etc.
321 */
322 struct request_sock *fastopen_rsk;
516}; 323};
517 324
518enum tsq_flags { 325enum tsq_flags {
@@ -552,6 +359,36 @@ static inline struct tcp_timewait_sock *tcp_twsk(const struct sock *sk)
552 return (struct tcp_timewait_sock *)sk; 359 return (struct tcp_timewait_sock *)sk;
553} 360}
554 361
555#endif /* __KERNEL__ */ 362static inline bool tcp_passive_fastopen(const struct sock *sk)
363{
364 return (sk->sk_state == TCP_SYN_RECV &&
365 tcp_sk(sk)->fastopen_rsk != NULL);
366}
367
368static inline bool fastopen_cookie_present(struct tcp_fastopen_cookie *foc)
369{
370 return foc->len != -1;
371}
372
373extern void tcp_sock_destruct(struct sock *sk);
374
375static inline int fastopen_init_queue(struct sock *sk, int backlog)
376{
377 struct request_sock_queue *queue =
378 &inet_csk(sk)->icsk_accept_queue;
379
380 if (queue->fastopenq == NULL) {
381 queue->fastopenq = kzalloc(
382 sizeof(struct fastopen_queue),
383 sk->sk_allocation);
384 if (queue->fastopenq == NULL)
385 return -ENOMEM;
386
387 sk->sk_destruct = tcp_sock_destruct;
388 spin_lock_init(&queue->fastopenq->lock);
389 }
390 queue->fastopenq->max_qlen = backlog;
391 return 0;
392}
556 393
557#endif /* _LINUX_TCP_H */ 394#endif /* _LINUX_TCP_H */
generated by cgit v1.2.2 (git 2.25.0) at 2025-10-14 08:52:21 -0400