Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 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> |
| 22 | |
| 23 | struct tcphdr { |
| 24 | __u16 source; |
| 25 | __u16 dest; |
| 26 | __u32 seq; |
| 27 | __u32 ack_seq; |
| 28 | #if defined(__LITTLE_ENDIAN_BITFIELD) |
| 29 | __u16 res1:4, |
| 30 | doff:4, |
| 31 | fin:1, |
| 32 | syn:1, |
| 33 | rst:1, |
| 34 | psh:1, |
| 35 | ack:1, |
| 36 | urg:1, |
| 37 | ece:1, |
| 38 | cwr:1; |
| 39 | #elif defined(__BIG_ENDIAN_BITFIELD) |
| 40 | __u16 doff:4, |
| 41 | res1:4, |
| 42 | cwr:1, |
| 43 | ece:1, |
| 44 | urg:1, |
| 45 | ack:1, |
| 46 | psh:1, |
| 47 | rst:1, |
| 48 | syn:1, |
| 49 | fin:1; |
| 50 | #else |
| 51 | #error "Adjust your <asm/byteorder.h> defines" |
| 52 | #endif |
| 53 | __u16 window; |
| 54 | __u16 check; |
| 55 | __u16 urg_ptr; |
| 56 | }; |
| 57 | |
| 58 | |
| 59 | enum { |
| 60 | TCP_ESTABLISHED = 1, |
| 61 | TCP_SYN_SENT, |
| 62 | TCP_SYN_RECV, |
| 63 | TCP_FIN_WAIT1, |
| 64 | TCP_FIN_WAIT2, |
| 65 | TCP_TIME_WAIT, |
| 66 | TCP_CLOSE, |
| 67 | TCP_CLOSE_WAIT, |
| 68 | TCP_LAST_ACK, |
| 69 | TCP_LISTEN, |
| 70 | TCP_CLOSING, /* now a valid state */ |
| 71 | |
| 72 | TCP_MAX_STATES /* Leave at the end! */ |
| 73 | }; |
| 74 | |
| 75 | #define TCP_STATE_MASK 0xF |
| 76 | #define TCP_ACTION_FIN (1 << 7) |
| 77 | |
| 78 | enum { |
| 79 | TCPF_ESTABLISHED = (1 << 1), |
| 80 | TCPF_SYN_SENT = (1 << 2), |
| 81 | TCPF_SYN_RECV = (1 << 3), |
| 82 | TCPF_FIN_WAIT1 = (1 << 4), |
| 83 | TCPF_FIN_WAIT2 = (1 << 5), |
| 84 | TCPF_TIME_WAIT = (1 << 6), |
| 85 | TCPF_CLOSE = (1 << 7), |
| 86 | TCPF_CLOSE_WAIT = (1 << 8), |
| 87 | TCPF_LAST_ACK = (1 << 9), |
| 88 | TCPF_LISTEN = (1 << 10), |
| 89 | TCPF_CLOSING = (1 << 11) |
| 90 | }; |
| 91 | |
| 92 | /* |
| 93 | * The union cast uses a gcc extension to avoid aliasing problems |
| 94 | * (union is compatible to any of its members) |
| 95 | * This means this part of the code is -fstrict-aliasing safe now. |
| 96 | */ |
| 97 | union tcp_word_hdr { |
| 98 | struct tcphdr hdr; |
| 99 | __u32 words[5]; |
| 100 | }; |
| 101 | |
| 102 | #define tcp_flag_word(tp) ( ((union tcp_word_hdr *)(tp))->words [3]) |
| 103 | |
| 104 | enum { |
| 105 | TCP_FLAG_CWR = __constant_htonl(0x00800000), |
| 106 | TCP_FLAG_ECE = __constant_htonl(0x00400000), |
| 107 | TCP_FLAG_URG = __constant_htonl(0x00200000), |
| 108 | TCP_FLAG_ACK = __constant_htonl(0x00100000), |
| 109 | TCP_FLAG_PSH = __constant_htonl(0x00080000), |
| 110 | TCP_FLAG_RST = __constant_htonl(0x00040000), |
| 111 | TCP_FLAG_SYN = __constant_htonl(0x00020000), |
| 112 | TCP_FLAG_FIN = __constant_htonl(0x00010000), |
| 113 | TCP_RESERVED_BITS = __constant_htonl(0x0F000000), |
| 114 | TCP_DATA_OFFSET = __constant_htonl(0xF0000000) |
| 115 | }; |
| 116 | |
| 117 | /* TCP socket options */ |
| 118 | #define TCP_NODELAY 1 /* Turn off Nagle's algorithm. */ |
| 119 | #define TCP_MAXSEG 2 /* Limit MSS */ |
| 120 | #define TCP_CORK 3 /* Never send partially complete segments */ |
| 121 | #define TCP_KEEPIDLE 4 /* Start keeplives after this period */ |
| 122 | #define TCP_KEEPINTVL 5 /* Interval between keepalives */ |
| 123 | #define TCP_KEEPCNT 6 /* Number of keepalives before death */ |
| 124 | #define TCP_SYNCNT 7 /* Number of SYN retransmits */ |
| 125 | #define TCP_LINGER2 8 /* Life time of orphaned FIN-WAIT-2 state */ |
| 126 | #define TCP_DEFER_ACCEPT 9 /* Wake up listener only when data arrive */ |
| 127 | #define TCP_WINDOW_CLAMP 10 /* Bound advertised window */ |
| 128 | #define TCP_INFO 11 /* Information about this connection. */ |
| 129 | #define TCP_QUICKACK 12 /* Block/reenable quick acks */ |
Stephen Hemminger | 5f8ef48 | 2005-06-23 20:37:36 -0700 | [diff] [blame] | 130 | #define TCP_CONGESTION 13 /* Congestion control algorithm */ |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 131 | |
| 132 | #define TCPI_OPT_TIMESTAMPS 1 |
| 133 | #define TCPI_OPT_SACK 2 |
| 134 | #define TCPI_OPT_WSCALE 4 |
| 135 | #define TCPI_OPT_ECN 8 |
| 136 | |
| 137 | enum tcp_ca_state |
| 138 | { |
| 139 | TCP_CA_Open = 0, |
| 140 | #define TCPF_CA_Open (1<<TCP_CA_Open) |
| 141 | TCP_CA_Disorder = 1, |
| 142 | #define TCPF_CA_Disorder (1<<TCP_CA_Disorder) |
| 143 | TCP_CA_CWR = 2, |
| 144 | #define TCPF_CA_CWR (1<<TCP_CA_CWR) |
| 145 | TCP_CA_Recovery = 3, |
| 146 | #define TCPF_CA_Recovery (1<<TCP_CA_Recovery) |
| 147 | TCP_CA_Loss = 4 |
| 148 | #define TCPF_CA_Loss (1<<TCP_CA_Loss) |
| 149 | }; |
| 150 | |
| 151 | struct tcp_info |
| 152 | { |
| 153 | __u8 tcpi_state; |
| 154 | __u8 tcpi_ca_state; |
| 155 | __u8 tcpi_retransmits; |
| 156 | __u8 tcpi_probes; |
| 157 | __u8 tcpi_backoff; |
| 158 | __u8 tcpi_options; |
| 159 | __u8 tcpi_snd_wscale : 4, tcpi_rcv_wscale : 4; |
| 160 | |
| 161 | __u32 tcpi_rto; |
| 162 | __u32 tcpi_ato; |
| 163 | __u32 tcpi_snd_mss; |
| 164 | __u32 tcpi_rcv_mss; |
| 165 | |
| 166 | __u32 tcpi_unacked; |
| 167 | __u32 tcpi_sacked; |
| 168 | __u32 tcpi_lost; |
| 169 | __u32 tcpi_retrans; |
| 170 | __u32 tcpi_fackets; |
| 171 | |
| 172 | /* Times. */ |
| 173 | __u32 tcpi_last_data_sent; |
| 174 | __u32 tcpi_last_ack_sent; /* Not remembered, sorry. */ |
| 175 | __u32 tcpi_last_data_recv; |
| 176 | __u32 tcpi_last_ack_recv; |
| 177 | |
| 178 | /* Metrics. */ |
| 179 | __u32 tcpi_pmtu; |
| 180 | __u32 tcpi_rcv_ssthresh; |
| 181 | __u32 tcpi_rtt; |
| 182 | __u32 tcpi_rttvar; |
| 183 | __u32 tcpi_snd_ssthresh; |
| 184 | __u32 tcpi_snd_cwnd; |
| 185 | __u32 tcpi_advmss; |
| 186 | __u32 tcpi_reordering; |
| 187 | |
| 188 | __u32 tcpi_rcv_rtt; |
| 189 | __u32 tcpi_rcv_space; |
| 190 | |
| 191 | __u32 tcpi_total_retrans; |
| 192 | }; |
| 193 | |
| 194 | #ifdef __KERNEL__ |
| 195 | |
| 196 | #include <linux/config.h> |
| 197 | #include <linux/skbuff.h> |
| 198 | #include <linux/ip.h> |
| 199 | #include <net/sock.h> |
| 200 | |
| 201 | /* This defines a selective acknowledgement block. */ |
| 202 | struct tcp_sack_block { |
| 203 | __u32 start_seq; |
| 204 | __u32 end_seq; |
| 205 | }; |
| 206 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 207 | struct tcp_options_received { |
| 208 | /* PAWS/RTTM data */ |
| 209 | long ts_recent_stamp;/* Time we stored ts_recent (for aging) */ |
| 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 */ |
| 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 */ |
| 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 */ |
| 225 | }; |
| 226 | |
Arnaldo Carvalho de Melo | 2e6599c | 2005-06-18 22:46:52 -0700 | [diff] [blame] | 227 | struct tcp_request_sock { |
| 228 | struct inet_request_sock req; |
| 229 | __u32 rcv_isn; |
| 230 | __u32 snt_isn; |
| 231 | }; |
| 232 | |
Arnaldo Carvalho de Melo | 60236fd | 2005-06-18 22:47:21 -0700 | [diff] [blame] | 233 | static inline struct tcp_request_sock *tcp_rsk(const struct request_sock *req) |
Arnaldo Carvalho de Melo | 2e6599c | 2005-06-18 22:46:52 -0700 | [diff] [blame] | 234 | { |
| 235 | return (struct tcp_request_sock *)req; |
| 236 | } |
| 237 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 238 | struct tcp_sock { |
| 239 | /* inet_sock has to be the first member of tcp_sock */ |
| 240 | struct inet_sock inet; |
| 241 | int tcp_header_len; /* Bytes of tcp header to send */ |
| 242 | |
| 243 | /* |
| 244 | * Header prediction flags |
| 245 | * 0x5?10 << 16 + snd_wnd in net byte order |
| 246 | */ |
| 247 | __u32 pred_flags; |
| 248 | |
| 249 | /* |
| 250 | * RFC793 variables by their proper names. This means you can |
| 251 | * read the code and the spec side by side (and laugh ...) |
| 252 | * See RFC793 and RFC1122. The RFC writes these in capitals. |
| 253 | */ |
| 254 | __u32 rcv_nxt; /* What we want to receive next */ |
| 255 | __u32 snd_nxt; /* Next sequence we send */ |
| 256 | |
| 257 | __u32 snd_una; /* First byte we want an ack for */ |
| 258 | __u32 snd_sml; /* Last byte of the most recently transmitted small packet */ |
| 259 | __u32 rcv_tstamp; /* timestamp of last received ACK (for keepalives) */ |
| 260 | __u32 lsndtime; /* timestamp of last sent data packet (for restart window) */ |
| 261 | struct tcp_bind_bucket *bind_hash; |
| 262 | /* Delayed ACK control data */ |
| 263 | struct { |
| 264 | __u8 pending; /* ACK is pending */ |
| 265 | __u8 quick; /* Scheduled number of quick acks */ |
| 266 | __u8 pingpong; /* The session is interactive */ |
| 267 | __u8 blocked; /* Delayed ACK was blocked by socket lock*/ |
| 268 | __u32 ato; /* Predicted tick of soft clock */ |
| 269 | unsigned long timeout; /* Currently scheduled timeout */ |
| 270 | __u32 lrcvtime; /* timestamp of last received data packet*/ |
| 271 | __u16 last_seg_size; /* Size of last incoming segment */ |
| 272 | __u16 rcv_mss; /* MSS used for delayed ACK decisions */ |
| 273 | } ack; |
| 274 | |
| 275 | /* Data for direct copy to user */ |
| 276 | struct { |
| 277 | struct sk_buff_head prequeue; |
| 278 | struct task_struct *task; |
| 279 | struct iovec *iov; |
| 280 | int memory; |
| 281 | int len; |
| 282 | } ucopy; |
| 283 | |
| 284 | __u32 snd_wl1; /* Sequence for window update */ |
| 285 | __u32 snd_wnd; /* The window we expect to receive */ |
| 286 | __u32 max_window; /* Maximal window ever seen from peer */ |
| 287 | __u32 pmtu_cookie; /* Last pmtu seen by socket */ |
| 288 | __u32 mss_cache; /* Cached effective mss, not including SACKS */ |
| 289 | __u16 mss_cache_std; /* Like mss_cache, but without TSO */ |
| 290 | __u16 ext_header_len; /* Network protocol overhead (IP/IPv6 options) */ |
| 291 | __u8 ca_state; /* State of fast-retransmit machine */ |
| 292 | __u8 retransmits; /* Number of unrecovered RTO timeouts. */ |
| 293 | |
| 294 | __u16 advmss; /* Advertised MSS */ |
| 295 | __u32 window_clamp; /* Maximal window to advertise */ |
| 296 | __u32 rcv_ssthresh; /* Current window clamp */ |
| 297 | |
| 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 | |
Stephen Hemminger | 317a76f | 2005-06-23 12:19:55 -0700 | [diff] [blame] | 302 | __u8 unused; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 303 | __u8 defer_accept; /* User waits for some data after accept() */ |
| 304 | |
| 305 | /* RTT measurement */ |
| 306 | __u32 srtt; /* smoothed round trip time << 3 */ |
| 307 | __u32 mdev; /* medium deviation */ |
| 308 | __u32 mdev_max; /* maximal mdev for the last rtt period */ |
| 309 | __u32 rttvar; /* smoothed mdev_max */ |
| 310 | __u32 rtt_seq; /* sequence number to update rttvar */ |
| 311 | __u32 rto; /* retransmit timeout */ |
| 312 | |
| 313 | __u32 packets_out; /* Packets which are "in flight" */ |
| 314 | __u32 left_out; /* Packets which leaved network */ |
| 315 | __u32 retrans_out; /* Retransmitted packets out */ |
| 316 | __u8 backoff; /* backoff */ |
| 317 | /* |
| 318 | * Options received (usually on last packet, some only on SYN packets). |
| 319 | */ |
| 320 | __u8 nonagle; /* Disable Nagle algorithm? */ |
| 321 | __u8 keepalive_probes; /* num of allowed keep alive probes */ |
| 322 | |
| 323 | __u8 probes_out; /* unanswered 0 window probes */ |
| 324 | struct tcp_options_received rx_opt; |
| 325 | |
| 326 | /* |
| 327 | * Slow start and congestion control (see also Nagle, and Karn & Partridge) |
| 328 | */ |
| 329 | __u32 snd_ssthresh; /* Slow start size threshold */ |
| 330 | __u32 snd_cwnd; /* Sending congestion window */ |
| 331 | __u16 snd_cwnd_cnt; /* Linear increase counter */ |
| 332 | __u16 snd_cwnd_clamp; /* Do not allow snd_cwnd to grow above this */ |
| 333 | __u32 snd_cwnd_used; |
| 334 | __u32 snd_cwnd_stamp; |
| 335 | |
| 336 | /* Two commonly used timers in both sender and receiver paths. */ |
| 337 | unsigned long timeout; |
| 338 | struct timer_list retransmit_timer; /* Resend (no ack) */ |
| 339 | struct timer_list delack_timer; /* Ack delay */ |
| 340 | |
| 341 | struct sk_buff_head out_of_order_queue; /* Out of order segments go here */ |
| 342 | |
| 343 | struct tcp_func *af_specific; /* Operations which are AF_INET{4,6} specific */ |
| 344 | |
| 345 | __u32 rcv_wnd; /* Current receiver window */ |
| 346 | __u32 rcv_wup; /* rcv_nxt on last window update sent */ |
| 347 | __u32 write_seq; /* Tail(+1) of data held in tcp send buffer */ |
| 348 | __u32 pushed_seq; /* Last pushed seq, required to talk to windows */ |
| 349 | __u32 copied_seq; /* Head of yet unread data */ |
| 350 | |
| 351 | /* SACKs data */ |
| 352 | struct tcp_sack_block duplicate_sack[1]; /* D-SACK block */ |
| 353 | struct tcp_sack_block selective_acks[4]; /* The SACKS themselves*/ |
| 354 | |
| 355 | __u8 syn_retries; /* num of allowed syn retries */ |
| 356 | __u8 ecn_flags; /* ECN status bits. */ |
| 357 | __u16 prior_ssthresh; /* ssthresh saved at recovery start */ |
| 358 | __u32 lost_out; /* Lost packets */ |
| 359 | __u32 sacked_out; /* SACK'd packets */ |
| 360 | __u32 fackets_out; /* FACK'd packets */ |
| 361 | __u32 high_seq; /* snd_nxt at onset of congestion */ |
| 362 | |
| 363 | __u32 retrans_stamp; /* Timestamp of the last retransmit, |
| 364 | * also used in SYN-SENT to remember stamp of |
| 365 | * the first SYN. */ |
| 366 | __u32 undo_marker; /* tracking retrans started here. */ |
| 367 | int undo_retrans; /* number of undoable retransmissions. */ |
| 368 | __u32 urg_seq; /* Seq of received urgent pointer */ |
| 369 | __u16 urg_data; /* Saved octet of OOB data and control flags */ |
| 370 | __u8 pending; /* Scheduled timer event */ |
| 371 | __u8 urg_mode; /* In urgent mode */ |
| 372 | __u32 snd_up; /* Urgent pointer */ |
| 373 | |
| 374 | __u32 total_retrans; /* Total retransmits for entire connection */ |
| 375 | |
Arnaldo Carvalho de Melo | 0e87506 | 2005-06-18 22:47:59 -0700 | [diff] [blame] | 376 | struct request_sock_queue accept_queue; /* FIFO of established children */ |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 377 | |
| 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 | |
| 382 | unsigned long last_synq_overflow; |
| 383 | |
| 384 | /* Receiver side RTT estimation */ |
| 385 | struct { |
| 386 | __u32 rtt; |
| 387 | __u32 seq; |
| 388 | __u32 time; |
| 389 | } rcv_rtt_est; |
| 390 | |
| 391 | /* Receiver queue space */ |
| 392 | struct { |
| 393 | int space; |
| 394 | __u32 seq; |
| 395 | __u32 time; |
| 396 | } rcvq_space; |
| 397 | |
Stephen Hemminger | 317a76f | 2005-06-23 12:19:55 -0700 | [diff] [blame] | 398 | /* Pluggable TCP congestion control hook */ |
| 399 | struct tcp_congestion_ops *ca_ops; |
| 400 | u32 ca_priv[16]; |
| 401 | #define TCP_CA_PRIV_SIZE (16*sizeof(u32)) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 402 | }; |
| 403 | |
| 404 | static inline struct tcp_sock *tcp_sk(const struct sock *sk) |
| 405 | { |
| 406 | return (struct tcp_sock *)sk; |
| 407 | } |
| 408 | |
Stephen Hemminger | 317a76f | 2005-06-23 12:19:55 -0700 | [diff] [blame] | 409 | static inline void *tcp_ca(const struct tcp_sock *tp) |
| 410 | { |
| 411 | return (void *) tp->ca_priv; |
| 412 | } |
| 413 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 414 | #endif |
| 415 | |
| 416 | #endif /* _LINUX_TCP_H */ |