1 /* 2 * Copyright (c) 2003, 2004 Jeffrey M. Hsu. All rights reserved. 3 * Copyright (c) 2003, 2004 The DragonFly Project. All rights reserved. 4 * 5 * This code is derived from software contributed to The DragonFly Project 6 * by Jeffrey M. Hsu. 7 * 8 * Redistribution and use in source and binary forms, with or without 9 * modification, are permitted provided that the following conditions 10 * are met: 11 * 1. Redistributions of source code must retain the above copyright 12 * notice, this list of conditions and the following disclaimer. 13 * 2. Redistributions in binary form must reproduce the above copyright 14 * notice, this list of conditions and the following disclaimer in the 15 * documentation and/or other materials provided with the distribution. 16 * 3. Neither the name of The DragonFly Project nor the names of its 17 * contributors may be used to endorse or promote products derived 18 * from this software without specific, prior written permission. 19 * 20 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS 21 * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT 22 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS 23 * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE 24 * COPYRIGHT HOLDERS OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, 25 * INCIDENTAL, SPECIAL, EXEMPLARY OR CONSEQUENTIAL DAMAGES (INCLUDING, 26 * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; 27 * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED 28 * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, 29 * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT 30 * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 31 * SUCH DAMAGE. 32 */ 33 34 /* 35 * Copyright (c) 1982, 1986, 1993, 1994, 1995 36 * The Regents of the University of California. All rights reserved. 37 * 38 * Redistribution and use in source and binary forms, with or without 39 * modification, are permitted provided that the following conditions 40 * are met: 41 * 1. Redistributions of source code must retain the above copyright 42 * notice, this list of conditions and the following disclaimer. 43 * 2. Redistributions in binary form must reproduce the above copyright 44 * notice, this list of conditions and the following disclaimer in the 45 * documentation and/or other materials provided with the distribution. 46 * 3. Neither the name of the University nor the names of its contributors 47 * may be used to endorse or promote products derived from this software 48 * without specific prior written permission. 49 * 50 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 51 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 52 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 53 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 54 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 55 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 56 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 57 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 58 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 59 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 60 * SUCH DAMAGE. 61 * 62 * @(#)tcp_var.h 8.4 (Berkeley) 5/24/95 63 * $FreeBSD: src/sys/netinet/tcp_var.h,v 1.56.2.13 2003/02/03 02:34:07 hsu Exp $ 64 */ 65 66 #ifndef _NETINET_TCP_VAR_H_ 67 #define _NETINET_TCP_VAR_H_ 68 69 #ifndef _NETINET_IN_PCB_H_ 70 #include <netinet/in_pcb.h> /* needed for in_conninfo, inp_gen_t */ 71 #endif 72 #ifndef _NETINET_TCP_H_ 73 #include <netinet/tcp.h> 74 #endif 75 76 /* 77 * Kernel variables for tcp. 78 */ 79 extern int tcp_do_rfc1323; 80 extern int tcp_low_rtobase; 81 extern int tcp_ncr_linklocal; 82 extern int tcp_ncr_rxtthresh_max; 83 extern int tcp_do_sack; 84 extern int tcp_do_smartsack; 85 extern int tcp_do_rescuesack; 86 extern int tcp_aggressive_rescuesack; 87 extern int tcp_do_rfc6675; 88 extern int tcp_rfc6675_rxt; 89 extern int tcp_aggregate_acks; 90 extern int tcp_eifel_rtoinc; 91 extern int tcp_prio_synack; 92 93 /* TCP segment queue entry */ 94 struct tseg_qent { 95 TAILQ_ENTRY(tseg_qent) tqe_q; 96 int tqe_len; /* TCP segment data length */ 97 struct tcphdr *tqe_th; /* a pointer to tcp header */ 98 struct mbuf *tqe_m; /* mbuf contains packet */ 99 }; 100 TAILQ_HEAD(tsegqe_head, tseg_qent); 101 extern int tcp_reass_maxseg; 102 extern int tcp_reass_qsize; 103 #ifdef MALLOC_DECLARE 104 MALLOC_DECLARE(M_TSEGQ); 105 #endif 106 107 struct tcptemp { 108 u_char tt_ipgen[40]; /* the size must be of max ip header, now IPv6 */ 109 struct tcphdr tt_t; 110 }; 111 112 #define tcp6cb tcpcb /* for KAME src sync over BSD*'s */ 113 114 struct raw_sackblock { /* covers [start, end) */ 115 tcp_seq rblk_start; 116 tcp_seq rblk_end; 117 }; 118 119 /* maximum number of SACK blocks that will fit in the TCP option space */ 120 #define MAX_SACK_REPORT_BLOCKS 4 121 122 TAILQ_HEAD(sackblock_list, sackblock); 123 124 struct scoreboard { 125 int nblocks; 126 struct sackblock_list sackblocks; 127 tcp_seq lostseq; /* passed SACK lost test */ 128 struct sackblock *lastfound; /* search hint */ 129 struct sackblock *freecache; /* one slot free block cache */ 130 }; 131 132 struct netmsg_tcp_timer; 133 struct netmsg_base; 134 135 struct tcp_pcbport { 136 struct inpcbport t_phd; 137 } __cachealign; 138 139 /* 140 * Tcp control block, one per tcp; fields: 141 * Organized for 16 byte cacheline efficiency. 142 */ 143 struct tcpcb { 144 struct tsegqe_head t_segq; 145 int t_dupacks; /* consecutive dup acks recd */ 146 int t_rxtthresh; /* # dup acks to start fast rxt */ 147 int tt_cpu; /* sanity check the cpu */ 148 149 struct tcp_pcbport *t_pcbport; /* per-cpu local port cache for 150 * accept(2)'ed sockets */ 151 152 struct tcp_callout *tt_rexmt; /* retransmit timer */ 153 struct tcp_callout *tt_persist;/* retransmit persistence */ 154 struct tcp_callout *tt_keep; /* keepalive */ 155 struct tcp_callout *tt_2msl; /* 2*msl TIME_WAIT timer */ 156 struct tcp_callout *tt_delack; /* delayed ACK timer */ 157 struct netmsg_tcp_timer *tt_msg; /* timer message */ 158 159 struct netmsg_base *tt_sndmore;/* send more segments (fairsend) */ 160 161 struct inpcb *t_inpcb; /* back pointer to internet pcb */ 162 int t_state; /* state of this connection */ 163 u_int t_flags; 164 #define TF_ACKNOW 0x00000001 /* ack peer immediately */ 165 #define TF_DELACK 0x00000002 /* ack, but try to delay it */ 166 #define TF_NODELAY 0x00000004 /* don't delay packets to coalesce */ 167 #define TF_NOOPT 0x00000008 /* don't use tcp options */ 168 #define TF_SENTFIN 0x00000010 /* have sent FIN */ 169 #define TF_REQ_SCALE 0x00000020 /* have/will request window scaling */ 170 #define TF_RCVD_SCALE 0x00000040 /* other side has requested scaling */ 171 #define TF_REQ_TSTMP 0x00000080 /* have/will request timestamps */ 172 #define TF_RCVD_TSTMP 0x00000100 /* a timestamp was received in SYN */ 173 #define TF_SACK_PERMITTED 0x00000200 /* other side said I could SACK */ 174 #define TF_NEEDSYN 0x00000400 /* send SYN (implicit state) */ 175 #define TF_NEEDFIN 0x00000800 /* send FIN (implicit state) */ 176 #define TF_NOPUSH 0x00001000 /* don't push */ 177 #define TF_LISTEN 0x00002000 /* listen(2) has been called */ 178 #define TF_SIGNATURE 0x00004000 /* require MD5 digests (RFC2385) */ 179 #define TF_NCR 0x00008000 /* Non-Congestion Robustness RFC4653 */ 180 #define TF_MORETOCOME 0x00010000 /* More data to be appended to sock */ 181 #define TF_SAWFIN 0x00020000 /* FIN has been seen */ 182 #define TF_LASTIDLE 0x00040000 /* connection was previously idle */ 183 #define TF_RXWIN0SENT 0x00080000 /* sent a receiver win 0 in response */ 184 #define TF_FASTRECOVERY 0x00100000 /* in Fast Recovery */ 185 #define TF_QUEDFIN 0x00200000 /* FIN has been received */ 186 #define TF_XMITNOW 0x00400000 /* Temporarily override Nagle */ 187 #define TF_UNUSED008 0x00800000 188 #define TF_UNUSED009 0x01000000 189 #define TF_FORCE 0x02000000 /* Set if forcing out a byte */ 190 #define TF_ONOUTPUTQ 0x04000000 /* on t_outputq list */ 191 #define TF_FAIRSEND 0x08000000 /* fairsend is requested */ 192 #define TF_UNUSED003 0x10000000 193 #define TF_UNUSED004 0x20000000 194 #define TF_KEEPALIVE 0x40000000 /* temporary keepalive */ 195 #define TF_RXRESIZED 0x80000000 /* rcvbuf was resized */ 196 tcp_seq snd_up; /* send urgent pointer */ 197 u_long snd_last; /* time last data were sent */ 198 199 tcp_seq snd_una; /* send unacknowledged */ 200 tcp_seq snd_recover; /* for use with Fast Recovery */ 201 tcp_seq snd_max; /* highest sequence number sent; 202 * used to recognize retransmits */ 203 tcp_seq snd_nxt; /* send next */ 204 205 tcp_seq snd_wl1; /* window update seg seq number */ 206 tcp_seq snd_wl2; /* window update seg ack number */ 207 tcp_seq iss; /* initial send sequence number */ 208 tcp_seq irs; /* initial receive sequence number */ 209 210 tcp_seq rcv_nxt; /* receive next */ 211 tcp_seq rcv_adv; /* advertised window */ 212 u_long rcv_wnd; /* receive window */ 213 tcp_seq rcv_up; /* receive urgent pointer */ 214 215 u_long snd_wnd; /* send window */ 216 u_long snd_cwnd; /* congestion-controlled window */ 217 u_long snd_wacked; /* bytes acked in one send window */ 218 u_long snd_ssthresh; /* snd_cwnd size threshold for 219 * for slow start exponential to 220 * linear switch */ 221 222 int t_rxtcur; /* current retransmit value (ticks) */ 223 u_int t_maxseg; /* maximum segment size */ 224 int t_srtt; /* smoothed round-trip time */ 225 int t_rttvar; /* variance in round-trip time */ 226 227 u_int t_maxopd; /* mss plus options */ 228 229 u_long t_rcvtime; /* reception inactivity time */ 230 u_long t_starttime; /* time connection was established */ 231 int t_rtttime; /* round trip time */ 232 tcp_seq t_rtseq; /* sequence number being timed */ 233 234 int t_rxtshift; /* log(2) of rexmt exp. backoff */ 235 u_int t_rttmin; /* minimum rtt allowed */ 236 u_int t_rttbest; /* best rtt we've seen */ 237 u_long t_rttupdated; /* number of times rtt sampled */ 238 u_long max_sndwnd; /* largest window peer has offered */ 239 240 int t_softerror; /* possible error not yet reported */ 241 /* out-of-band data */ 242 char t_oobflags; /* have some */ 243 char t_iobc; /* input character */ 244 #define TCPOOB_HAVEDATA 0x01 245 #define TCPOOB_HADDATA 0x02 246 247 /* RFC 1323 variables */ 248 u_char snd_scale; /* window scaling for send window */ 249 u_char rcv_scale; /* window scaling for recv window */ 250 u_char request_r_scale; /* pending window scaling */ 251 u_long ts_recent; /* timestamp echo data */ 252 253 u_long ts_recent_age; /* when last updated */ 254 tcp_seq last_ack_sent; 255 256 /* experimental */ 257 u_int rxt_flags; 258 #define TRXT_F_REBASERTO 0x0001 /* Recalculate RTO based on new RTT */ 259 #define TRXT_F_WASFRECOVERY 0x0002 /* was in Fast Recovery */ 260 #define TRXT_F_FIRSTACCACK 0x0004 /* Look for 1st acceptable ACK. */ 261 #define TRXT_F_FASTREXMT 0x0008 /* Did Fast Retransmit. */ 262 #define TRXT_F_EARLYREXMT 0x0010 /* Did Early (Fast) Retransmit. */ 263 int t_srtt_prev; /* adjusted SRTT prior to retransmit */ 264 int t_rttvar_prev; /* RTTVAR prior to retransmit */ 265 int t_rxtcur_prev; /* rexmt timeout prior to retransmit */ 266 tcp_seq snd_max_prev; /* SND_MAX prior to retransmit */ 267 u_long snd_cwnd_prev; /* cwnd prior to retransmit */ 268 u_long snd_wacked_prev; /* prior bytes acked in send window */ 269 u_long snd_ssthresh_prev; /* ssthresh prior to retransmit */ 270 tcp_seq snd_recover_prev; /* snd_recover prior to retransmit */ 271 u_long t_badrxtwin; /* window for retransmit recovery */ 272 u_long t_rexmtTS; /* timestamp of last retransmit */ 273 u_char snd_limited; /* segments limited transmitted */ 274 275 u_int sack_flags; 276 #define TSACK_F_SACKRESCUED 0x0001 /* sent rescue SACK recovery data */ 277 #define TSACK_F_DUPSEG 0x0002 /* last seg a duplicate */ 278 #define TSACK_F_ENCLOSESEG 0x0004 /* enclosing SACK block */ 279 #define TSACK_F_SACKLEFT 0x0008 /* send SACK blocks from left side */ 280 tcp_seq rexmt_high; /* highest seq # retransmitted + 1 */ 281 tcp_seq rexmt_rescue; /* rescue SACKED sequence number */ 282 tcp_seq snd_max_rexmt; /* snd_max when rexmting snd_una */ 283 struct scoreboard scb; /* sack scoreboard */ 284 struct raw_sackblock reportblk; /* incoming segment or D-SACK block */ 285 struct raw_sackblock encloseblk; 286 int nsackhistory; 287 struct raw_sackblock sackhistory[MAX_SACK_REPORT_BLOCKS]; /* reported */ 288 289 TAILQ_ENTRY(tcpcb) t_outputq; /* tcp_output needed list */ 290 291 /* bandwith limitation */ 292 u_long snd_bandwidth; /* calculated bandwidth or 0 */ 293 u_long snd_bwnd; /* bandwidth-controlled window */ 294 int t_bw_rtttime; /* used for bandwidth calculation */ 295 tcp_seq t_bw_rtseq; /* used for bandwidth calculation */ 296 297 /* anti DoS counters */ 298 u_long rcv_second; /* start of interval second */ 299 u_long rcv_pps; /* received packets per second */ 300 u_long rcv_byps; /* received bytes per second */ 301 302 u_int32_t rfbuf_ts; /* recv buffer autoscaling timestamp */ 303 int rfbuf_cnt; /* recv buffer autoscaling byte count */ 304 305 int t_keepinit; /* time to establish connection */ 306 307 int t_keepidle; /* time before keepalive probes begin */ 308 int t_keepintvl; /* time between keepalive probes */ 309 int t_keepcnt; /* maximum number of keepalive probes */ 310 int t_maxidle; /* time to drop after starting probes */ 311 312 int t_rxtsyn; /* time spent in SYN or SYN|ACK rexmt */ 313 }; 314 315 #define IN_FASTRECOVERY(tp) (tp->t_flags & TF_FASTRECOVERY) 316 #define ENTER_FASTRECOVERY(tp) tp->t_flags |= TF_FASTRECOVERY 317 #define EXIT_FASTRECOVERY(tp) tp->t_flags &= ~TF_FASTRECOVERY 318 319 #ifdef TCP_SIGNATURE 320 /* 321 * Defines which are needed by the xform_tcp module and tcp_[in|out]put 322 * for SADB verification and lookup. 323 */ 324 #define TCP_SIGLEN 16 /* length of computed digest in bytes */ 325 #define TCP_KEYLEN_MIN 1 /* minimum length of TCP-MD5 key */ 326 #define TCP_KEYLEN_MAX 80 /* maximum length of TCP-MD5 key */ 327 /* 328 * Only a single SA per host may be specified at this time. An SPI is 329 * needed in order for the KEY_ALLOCSA() lookup to work. 330 */ 331 #define TCP_SIG_SPI 0x1000 332 #endif /* TCP_SIGNATURE */ 333 334 /* 335 * TCP statistics. 336 * 337 * NOTE: Make sure this struct's size is multiple cache line size. 338 */ 339 struct tcp_stats { 340 u_long tcps_connattempt; /* connections initiated */ 341 u_long tcps_accepts; /* connections accepted */ 342 u_long tcps_connects; /* connections established */ 343 u_long tcps_drops; /* connections dropped */ 344 u_long tcps_conndrops; /* embryonic connections dropped */ 345 u_long tcps_minmssdrops; /* average minmss too low drops */ 346 u_long tcps_closed; /* conn. closed (includes drops) */ 347 u_long tcps_segstimed; /* segs where we tried to get rtt */ 348 u_long tcps_rttupdated; /* times we succeeded */ 349 u_long tcps_delack; /* delayed acks sent */ 350 u_long tcps_timeoutdrop; /* conn. dropped in rxmt timeout */ 351 u_long tcps_rexmttimeo; /* retransmit timeouts */ 352 u_long tcps_persisttimeo; /* persist timeouts */ 353 u_long tcps_keeptimeo; /* keepalive timeouts */ 354 u_long tcps_keepprobe; /* keepalive probes sent */ 355 u_long tcps_keepdrops; /* connections dropped in keepalive */ 356 357 u_long tcps_sndtotal; /* total packets sent */ 358 u_long tcps_sndpack; /* data packets sent */ 359 u_long tcps_sndbyte; /* data bytes sent */ 360 u_long tcps_sndrexmitpack; /* data packets retransmitted */ 361 u_long tcps_sndrexmitbyte; /* data bytes retransmitted */ 362 u_long tcps_sndsackrtopack; /* packets sent by SACK after RTO */ 363 u_long tcps_sndsackrtobyte; /* bytes sent by SACK after RTO */ 364 u_long tcps_sndfastrexmit; /* Fast Retransmissions */ 365 u_long tcps_sndearlyrexmit; /* early Fast Retransmissions */ 366 u_long tcps_sndlimited; /* Limited Transmit packets */ 367 u_long tcps_sndrtobad; /* spurious RTO retransmissions */ 368 u_long tcps_sndfastrexmitbad; /* spurious Fast Retransmissions */ 369 u_long tcps_sndearlyrexmitbad; /* spurious early Fast Retransmissions, 370 a subset of tcps_sndfastrexmitbad */ 371 u_long tcps_eifeldetected; /* Eifel-detected spurious rexmits */ 372 u_long tcps_rttcantdetect; /* Eifel but not 1/2 RTT-detectable */ 373 u_long tcps_rttdetected; /* RTT-detected spurious RTO rexmits */ 374 u_long tcps_sndacks; /* ack-only packets sent */ 375 u_long tcps_sndprobe; /* window probes sent */ 376 u_long tcps_sndurg; /* packets sent with URG only */ 377 u_long tcps_sndwinup; /* window update-only packets sent */ 378 u_long tcps_sndctrl; /* control (SYN|FIN|RST) packets sent */ 379 u_long tcps_sndsackpack; /* packets sent by SACK recovery alg */ 380 u_long tcps_sndsackbyte; /* bytes sent by SACK recovery */ 381 u_long tcps_snduna3; /* re-retransmit snd_una on 3 new seg */ 382 u_long tcps_snduna1; /* re-retransmit snd_una on 1 new seg */ 383 u_long tcps_sndsackopt; /* SACK options sent */ 384 u_long tcps_snddsackopt; /* D-SACK options sent */ 385 u_long tcps_sndidle; /* sending idle detected */ 386 u_long tcps_sackrescue; /* SACK rescue data packets sent */ 387 u_long tcps_sackrescue_try; /* SACK rescues attempted */ 388 u_long tcps_eifelresponse; /* Eifel responses */ 389 390 u_long tcps_rcvtotal; /* total packets received */ 391 u_long tcps_rcvpack; /* packets received in sequence */ 392 u_long tcps_rcvbyte; /* bytes received in sequence */ 393 u_long tcps_rcvbadsum; /* packets received with ccksum errs */ 394 u_long tcps_rcvbadoff; /* packets received with bad offset */ 395 u_long tcps_rcvmemdrop; /* packets dropped for lack of memory */ 396 u_long tcps_rcvshort; /* packets received too short */ 397 u_long tcps_rcvduppack; /* duplicate-only packets received */ 398 u_long tcps_rcvdupbyte; /* duplicate-only bytes received */ 399 u_long tcps_rcvpartduppack; /* packets with some duplicate data */ 400 u_long tcps_rcvpartdupbyte; /* dup. bytes in part-dup. packets */ 401 u_long tcps_rcvoopack; /* out-of-order packets received */ 402 u_long tcps_rcvoobyte; /* out-of-order bytes received */ 403 u_long tcps_rcvpackafterwin; /* packets with data after window */ 404 u_long tcps_rcvbyteafterwin; /* bytes rcvd after window */ 405 u_long tcps_rcvafterclose; /* packets rcvd after "close" */ 406 u_long tcps_rcvwinprobe; /* rcvd window probe packets */ 407 u_long tcps_rcvdupack; /* rcvd duplicate acks */ 408 u_long tcps_rcvacktoomuch; /* rcvd acks for unsent data */ 409 u_long tcps_rcvackpack; /* rcvd ack packets */ 410 u_long tcps_rcvackbyte; /* bytes acked by rcvd acks */ 411 u_long tcps_rcvwinupd; /* rcvd window update packets */ 412 u_long tcps_pawsdrop; /* segments dropped due to PAWS */ 413 u_long tcps_pawsaccept; /* segments accepted, PAWS tolerance */ 414 u_long tcps_predack; /* times hdr predict ok for acks */ 415 u_long tcps_preddat; /* times hdr predict ok for data pkts */ 416 u_long tcps_pcbcachemiss; 417 u_long tcps_cachedrtt; /* times cached RTT in route updated */ 418 u_long tcps_cachedrttvar; /* times cached rttvar updated */ 419 u_long tcps_cachedssthresh; /* times cached ssthresh updated */ 420 u_long tcps_usedrtt; /* times RTT initialized from route */ 421 u_long tcps_usedrttvar; /* times RTTVAR initialized from rt */ 422 u_long tcps_usedssthresh; /* times ssthresh initialized from rt*/ 423 u_long tcps_persistdrop; /* timeout in persist state */ 424 u_long tcps_badsyn; /* bogus SYN, e.g. premature ACK */ 425 u_long tcps_mturesent; /* resends due to MTU discovery */ 426 u_long tcps_listendrop; /* listen queue overflows */ 427 u_long tcps_rcvbadsackopt; /* rcvd illegal SACK options */ 428 u_long tcps_sackrenege; /* times other side reneged */ 429 430 u_long tcps_sacksbupdate; /* times SACK scoreboard updated */ 431 u_long tcps_sacksboverflow; /* times SACK scoreboard overflowed */ 432 u_long tcps_sacksbreused; /* times SACK sb-block reused */ 433 u_long tcps_sacksbfailed; /* times SACK sb update failed */ 434 u_long tcps_sacksbfast; /* times SACK sb-block uses cache */ 435 436 u_long tcps_sc_added; /* entry added to syncache */ 437 u_long tcps_sc_retransmitted; /* syncache entry was retransmitted */ 438 u_long tcps_sc_dupsyn; /* duplicate SYN packet */ 439 u_long tcps_sc_dropped; /* could not reply to packet */ 440 u_long tcps_sc_completed; /* successful extraction of entry */ 441 u_long tcps_sc_bucketoverflow; /* syncache per-bucket limit hit */ 442 u_long tcps_sc_cacheoverflow; /* syncache cache limit hit */ 443 u_long tcps_sc_reset; /* RST removed entry from syncache */ 444 u_long tcps_sc_stale; /* timed out or listen socket gone */ 445 u_long tcps_sc_aborted; /* syncache entry aborted */ 446 u_long tcps_sc_badack; /* removed due to bad ACK */ 447 u_long tcps_sc_unreach; /* ICMP unreachable received */ 448 u_long tcps_sc_zonefail; /* zalloc() failed */ 449 u_long tcps_sc_sendcookie; /* SYN cookie sent */ 450 u_long tcps_sc_recvcookie; /* SYN cookie received */ 451 452 u_long tcps_pad[6]; /* pad to cache line size (64B) */ 453 }; 454 #ifdef _KERNEL 455 CTASSERT((sizeof(struct tcp_stats) & __VM_CACHELINE_MASK) == 0); 456 #endif 457 458 #ifdef _KERNEL 459 460 #ifndef _NETINET_TCP_FSM_H_ 461 #include <netinet/tcp_fsm.h> 462 #endif 463 464 struct tcp_state_count { 465 u_long tcps_count[TCP_NSTATES]; 466 } __cachealign; 467 468 #define tcpstat tcpstats_percpu[mycpuid] 469 470 struct sockopt; 471 472 extern struct tcp_stats tcpstats_percpu[MAXCPU]; 473 extern struct tcp_state_count tcpstate_count[MAXCPU]; 474 475 static const int tcprexmtthresh = 3; 476 #endif 477 478 /* 479 * Structure to hold TCP options that are only used during segment 480 * processing (in tcp_input), but not held in the tcpcb. 481 * It's basically used to reduce the number of parameters 482 * to tcp_dooptions. 483 */ 484 struct tcpopt { 485 u_int to_flags; /* which options are present */ 486 #define TOF_TS 0x0001 /* timestamp */ 487 #define TOF_MSS 0x0010 488 #define TOF_SCALE 0x0020 489 #define TOF_SACK_PERMITTED 0x0040 490 #define TOF_SACK 0x0080 491 #define TOF_SIGNATURE 0x0100 /* signature option present */ 492 #define TOF_SIGLEN 0x0200 /* signature length valid (RFC2385) */ 493 #define TOF_DSACK 0x0400 /* D-SACK */ 494 #define TOF_SACK_REDUNDANT 0x0800 /* all SACK blocks are known */ 495 u_int32_t to_tsval; 496 u_int32_t to_tsecr; 497 u_int16_t to_mss; 498 u_int8_t to_requested_s_scale; 499 u_int8_t to_nsackblocks; 500 struct raw_sackblock *to_sackblocks; 501 }; 502 503 struct syncache { 504 inp_gen_t sc_inp_gencnt; /* pointer check */ 505 struct tcpcb *sc_tp; /* tcb for listening socket */ 506 struct mbuf *sc_ipopts; /* source route */ 507 struct in_conninfo sc_inc; /* addresses */ 508 #define sc_route sc_inc.inc_route 509 #define sc_route6 sc_inc.inc6_route 510 u_int32_t sc_tsrecent; 511 uint16_t sc_hashval; /* connection hash */ 512 uint16_t sc_pad; /* explicit padding */ 513 tcp_seq sc_irs; /* seq from peer */ 514 tcp_seq sc_iss; /* our ISS */ 515 u_long sc_rxttime; /* retransmit time */ 516 u_int16_t sc_rxtslot; /* retransmit counter */ 517 u_int16_t sc_peer_mss; /* peer's MSS */ 518 u_int16_t sc_wnd; /* advertised window */ 519 u_int8_t sc_requested_s_scale:4, 520 sc_request_r_scale:4; 521 u_int8_t sc_flags; 522 #define SCF_NOOPT 0x01 /* no TCP options */ 523 #define SCF_WINSCALE 0x02 /* negotiated window scaling */ 524 #define SCF_TIMESTAMP 0x04 /* negotiated timestamps */ 525 #define SCF_HASH 0x08 /* sc_hashval is valid */ 526 #define SCF_UNREACH 0x10 /* icmp unreachable received */ 527 #define SCF_SACK_PERMITTED 0x20 /* saw SACK permitted option */ 528 #define SCF_SIGNATURE 0x40 /* send MD5 digests */ 529 #define SCF_MARKER 0x80 /* not a real entry */ 530 int sc_rxtused; /* time spent in SYN|ACK rxt */ 531 u_long sc_sndwnd; /* send window */ 532 TAILQ_ENTRY(syncache) sc_hash; 533 TAILQ_ENTRY(syncache) sc_timerq; 534 }; 535 536 struct syncache_head { 537 TAILQ_HEAD(, syncache) sch_bucket; 538 u_int sch_length; 539 }; 540 541 #define intotcpcb(ip) ((struct tcpcb *)(ip)->inp_ppcb) 542 #define sototcpcb(so) (intotcpcb(sotoinpcb(so))) 543 544 /* 545 * The smoothed round-trip time and estimated variance 546 * are stored as fixed point numbers scaled by the values below. 547 * For convenience, these scales are also used in smoothing the average 548 * (smoothed = (1/scale)sample + ((scale-1)/scale)smoothed). 549 * With these scales, srtt has 3 bits to the right of the binary point, 550 * and thus an "ALPHA" of 0.875. rttvar has 2 bits to the right of the 551 * binary point, and is smoothed with an ALPHA of 0.75. 552 */ 553 #define TCP_RTT_SCALE 32 /* multiplier for srtt; 3 bits frac. */ 554 #define TCP_RTT_SHIFT 5 /* shift for srtt; 3 bits frac. */ 555 #define TCP_RTTVAR_SCALE 16 /* multiplier for rttvar; 2 bits */ 556 #define TCP_RTTVAR_SHIFT 4 /* shift for rttvar; 2 bits */ 557 #define TCP_DELTA_SHIFT 2 /* see tcp_input.c */ 558 559 /* 560 * The initial retransmission should happen at rtt + 4 * rttvar. 561 * Because of the way we do the smoothing, srtt and rttvar 562 * will each average +1/2 tick of bias. When we compute 563 * the retransmit timer, we want 1/2 tick of rounding and 564 * 1 extra tick because of +-1/2 tick uncertainty in the 565 * firing of the timer. The bias will give us exactly the 566 * 1.5 tick we need. But, because the bias is 567 * statistical, we have to test that we don't drop below 568 * the minimum feasible timer (which is 2 ticks). 569 * This version of the macro adapted from a paper by Lawrence 570 * Brakmo and Larry Peterson which outlines a problem caused 571 * by insufficient precision in the original implementation, 572 * which results in inappropriately large RTO values for very 573 * fast networks. 574 */ 575 #define TCP_REXMTVAL(tp) \ 576 max((tp)->t_rttmin, (((tp)->t_srtt >> (TCP_RTT_SHIFT - TCP_DELTA_SHIFT)) \ 577 + (tp)->t_rttvar) >> TCP_DELTA_SHIFT) 578 579 /* 580 * TCB structure exported to user-land via sysctl(3). 581 * Evil hack: declare only if in_pcb.h and sys/socketvar.h have been 582 * included. Not all of our clients do. 583 */ 584 #if defined(_NETINET_IN_PCB_H_) && defined(_SYS_SOCKETVAR_H_) 585 struct xtcpcb { 586 size_t xt_len; 587 struct inpcb xt_inp; 588 struct tcpcb xt_tp; 589 struct xsocket xt_socket; 590 u_quad_t xt_alignment_hack; 591 }; 592 #endif 593 594 /* 595 * Names for TCP sysctl objects 596 */ 597 #define TCPCTL_DO_RFC1323 1 /* use RFC-1323 extensions */ 598 /* 2 was TCPCTL_DO_RFC1644 */ 599 #define TCPCTL_MSSDFLT 3 /* MSS default */ 600 #define TCPCTL_STATS 4 /* statistics (read-only) */ 601 #define TCPCTL_RTTDFLT 5 /* default RTT estimate */ 602 #define TCPCTL_KEEPIDLE 6 /* keepalive idle timer */ 603 #define TCPCTL_KEEPINTVL 7 /* interval to send keepalives */ 604 #define TCPCTL_SENDSPACE 8 /* send buffer space */ 605 #define TCPCTL_RECVSPACE 9 /* receive buffer space */ 606 #define TCPCTL_KEEPINIT 10 /* timeout for establishing syn */ 607 #define TCPCTL_PCBLIST 11 /* list of all outstanding PCBs */ 608 #define TCPCTL_DELACKTIME 12 /* time before sending delayed ACK */ 609 #define TCPCTL_V6MSSDFLT 13 /* MSS default for IPv6 */ 610 #define TCPCTL_MAXID 14 611 612 #define TCPCTL_NAMES { \ 613 { 0, 0 }, \ 614 { "rfc1323", CTLTYPE_INT }, \ 615 { "reserved", CTLTYPE_INT}, /* was rfc1644 */ \ 616 { "mssdflt", CTLTYPE_INT }, \ 617 { "stats", CTLTYPE_STRUCT }, \ 618 { "rttdflt", CTLTYPE_INT }, \ 619 { "keepidle", CTLTYPE_INT }, \ 620 { "keepintvl", CTLTYPE_INT }, \ 621 { "sendspace", CTLTYPE_INT }, \ 622 { "recvspace", CTLTYPE_INT }, \ 623 { "keepinit", CTLTYPE_INT }, \ 624 { "pcblist", CTLTYPE_STRUCT }, \ 625 { "delacktime", CTLTYPE_INT }, \ 626 { "v6mssdflt", CTLTYPE_INT }, \ 627 } 628 629 #ifdef _KERNEL 630 #ifdef SYSCTL_DECL 631 SYSCTL_DECL(_net_inet_tcp); 632 #endif 633 634 #define TCP_DO_SACK(tp) ((tp)->t_flags & TF_SACK_PERMITTED) 635 #define TCP_DO_NCR(tp) (((tp)->t_flags & TF_NCR) && TCP_DO_SACK((tp))) 636 #define TCP_SACK_BLKEND(len, thflags) \ 637 ((len) + (((thflags) & TH_FIN) != 0)) 638 639 struct tcpcbackq { 640 TAILQ_HEAD(, tcpcb) head; 641 } __cachealign; 642 643 extern struct inpcbinfo tcbinfo[]; 644 extern struct tcpcbackq tcpcbackq[]; 645 646 extern int tcp_mssdflt; /* XXX */ 647 extern int tcp_minmss; 648 extern int tcp_delack_enabled; 649 extern int path_mtu_discovery; 650 651 struct ip; 652 union netmsg; 653 654 int tcp_addrcpu(in_addr_t faddr, in_port_t fport, 655 in_addr_t laddr, in_port_t lport); 656 int tcp_addrhash(in_addr_t faddr, in_port_t fport, 657 in_addr_t laddr, in_port_t lport); 658 struct lwkt_port * 659 tcp_addrport(in_addr_t faddr, in_port_t fport, 660 in_addr_t laddr, in_port_t lport); 661 struct lwkt_port *tcp_addrport0(void); 662 void tcp_canceltimers (struct tcpcb *); 663 struct tcpcb * 664 tcp_close (struct tcpcb *); 665 void tcp_ctlinput(union netmsg *); 666 void tcp_ctloutput(union netmsg *); 667 struct netmsg_pr_ctloutput *tcp_ctloutmsg(struct sockopt *); 668 inp_notify_t tcp_get_inpnotify(int cmd, const struct sockaddr *sa, 669 int *arg, struct ip **ip0, int *cpuid); 670 struct tcpcb * 671 tcp_drop (struct tcpcb *, int); 672 void tcp_drain (void); 673 void tcp_init (void); 674 void tcp_thread_init (void); 675 int tcp_input (struct mbuf **, int *, int); 676 void tcp_rmx_init (struct tcpcb *, int); 677 int tcp_mssopt (struct tcpcb *); 678 void tcp_drop_syn_sent (struct inpcb *, int); 679 void tcp_mtudisc (struct inpcb *, int); 680 void tcp_newtcpcb (struct inpcb *); 681 int tcp_output(struct tcpcb *); 682 int tcp_output_fair(struct tcpcb *); 683 void tcp_output_init(struct tcpcb *); 684 void tcp_output_cancel(struct tcpcb *); 685 boolean_t 686 tcp_output_pending(struct tcpcb *); 687 void tcp_quench (struct inpcb *, int); 688 void tcp_respond (struct tcpcb *, void *, 689 struct tcphdr *, struct mbuf *, tcp_seq, tcp_seq, int); 690 struct rtentry * 691 tcp_rtlookup (struct in_conninfo *); 692 int tcp_sack_bytes_below(const struct scoreboard *scb, tcp_seq seq); 693 void tcp_sack_destroy(struct scoreboard *scb); 694 void tcp_sack_discard(struct tcpcb *tp); 695 void tcp_sack_report_cleanup(struct tcpcb *tp); 696 boolean_t 697 tcp_sack_report_needed(const struct tcpcb *tp); 698 int tcp_sack_ndsack_blocks(const struct raw_sackblock *blocks, 699 const int numblocks, tcp_seq snd_una); 700 void tcp_sack_fill_report(struct tcpcb *tp, u_char *opt, u_int *plen); 701 boolean_t 702 tcp_sack_has_sacked(const struct scoreboard *scb, u_int amount); 703 void tcp_sack_tcpcb_init(struct tcpcb *tp); 704 uint32_t tcp_sack_compute_pipe(const struct tcpcb *tp); 705 boolean_t 706 tcp_sack_nextseg(struct tcpcb *tp, tcp_seq *nextrexmt, uint32_t *len, 707 boolean_t *rescue); 708 boolean_t 709 tcp_sack_islost(const struct scoreboard *scb, tcp_seq seq); 710 void tcp_sack_update_lostseq(struct scoreboard *scb, tcp_seq snd_una, 711 u_int maxseg, int rxtthresh); 712 #ifdef later 713 void tcp_sack_revert_scoreboard(struct scoreboard *scb, tcp_seq snd_una, 714 u_int maxseg); 715 void tcp_sack_save_scoreboard(struct scoreboard *scb); 716 #endif 717 void tcp_sack_skip_sacked(struct scoreboard *scb, tcp_seq *prexmt); 718 uint32_t tcp_sack_first_unsacked_len(const struct tcpcb *tp); 719 void tcp_sack_update_scoreboard(struct tcpcb *tp, struct tcpopt *to); 720 void tcp_save_congestion_state(struct tcpcb *tp); 721 void tcp_revert_congestion_state(struct tcpcb *tp); 722 void tcp_setpersist (struct tcpcb *); 723 struct tcptemp *tcp_maketemplate (struct tcpcb *); 724 void tcp_freetemplate (struct tcptemp *); 725 void tcp_fillheaders (struct tcpcb *, void *, void *, boolean_t); 726 struct lwkt_port * 727 tcp_soport(struct socket *, struct sockaddr *, struct mbuf **); 728 struct lwkt_port * 729 tcp_ctlport(int, struct sockaddr *, void *, int *); 730 struct lwkt_port * 731 tcp_initport(void); 732 struct tcpcb * 733 tcp_timers (struct tcpcb *, int); 734 void tcp_trace (short, short, struct tcpcb *, void *, struct tcphdr *, 735 int); 736 void tcp_xmit_bandwidth_limit(struct tcpcb *tp, tcp_seq ack_seq); 737 u_long tcp_initial_window(struct tcpcb *tp); 738 void tcp_timer_keep_activity(struct tcpcb *tp, int thflags); 739 void syncache_init(void); 740 void syncache_unreach(struct in_conninfo *, const struct tcphdr *); 741 int syncache_expand(struct in_conninfo *, struct tcphdr *, 742 struct socket **, struct mbuf *); 743 int syncache_add(struct in_conninfo *, struct tcpopt *, 744 struct tcphdr *, struct socket *, struct mbuf *); 745 void syncache_chkrst(struct in_conninfo *, struct tcphdr *); 746 void syncache_badack(struct in_conninfo *); 747 void syncache_destroy(struct tcpcb *tp, struct tcpcb *new_tp); 748 749 #ifdef TCP_SIGNATURE 750 int tcpsignature_apply(void *fstate, void *data, unsigned int len); 751 int tcpsignature_compute(struct mbuf *m, int len, int tcpoptlen, 752 u_char *buf, u_int direction); 753 #endif /* TCP_SIGNATURE */ 754 755 extern struct pr_usrreqs tcp_usrreqs; 756 extern u_long tcp_sendspace; 757 extern u_long tcp_recvspace; 758 tcp_seq tcp_new_isn (struct tcpcb *); 759 760 void tcp_pcbport_create(struct tcpcb *); 761 void tcp_pcbport_destroy(struct tcpcb *); 762 void tcp_pcbport_merge_oncpu(struct tcpcb *); 763 764 static __inline void 765 tcp_pcbport_insert(struct tcpcb *ltp, struct inpcb *inp) 766 { 767 struct inpcbport *phd; 768 int cpu; 769 770 if (inp->inp_lport != ltp->t_inpcb->inp_lport) { 771 /* 772 * This could happen with 'ipfw forward'. 773 */ 774 in_pcbinsporthash_lport(inp); 775 return; 776 } 777 778 cpu = mycpuid; 779 KASSERT(cpu < netisr_ncpus, ("invalid cpu%d", cpu)); 780 phd = <p->t_pcbport[cpu].t_phd; 781 782 /* 783 * NOTE: 784 * Set inp_porthash NULL and set inp_phd properly, 785 * so that tcp_pcbport_remove() could tell that this 786 * inpcb is on the listen tcpcb per-cpu port cache. 787 */ 788 inp->inp_porthash = NULL; 789 inp->inp_phd = phd; 790 LIST_INSERT_HEAD(&phd->phd_pcblist, inp, inp_portlist); 791 } 792 793 static __inline void 794 tcp_pcbport_remove(struct inpcb *inp) 795 { 796 if (inp->inp_porthash == NULL && inp->inp_phd != NULL) { 797 /* 798 * On listen tcpcb per-cpu port cache. 799 */ 800 LIST_REMOVE(inp, inp_portlist); 801 inp->inp_phd = NULL; 802 /* NOTE: Don't whack inp_lport, which may be used later */ 803 } 804 } 805 806 static __inline void 807 _TCP_STATE_INC(const struct tcpcb *tp) 808 { 809 tcpstate_count[mycpuid].tcps_count[tp->t_state]++; 810 } 811 812 static __inline void 813 _TCP_STATE_DEC(const struct tcpcb *tp) 814 { 815 tcpstate_count[mycpuid].tcps_count[tp->t_state]--; 816 } 817 818 static __inline void 819 _TCP_STATE_SET(struct tcpcb *tp, int state) 820 { 821 tp->t_state = state; 822 _TCP_STATE_INC(tp); 823 } 824 825 static __inline void 826 TCP_STATE_INIT(struct tcpcb *tp) 827 { 828 _TCP_STATE_SET(tp, TCPS_CLOSED); 829 } 830 831 static __inline void 832 TCP_STATE_TERM(struct tcpcb *tp) 833 { 834 KASSERT(tp->t_state != TCPS_TERMINATING, ("tcpcb was terminated")); 835 _TCP_STATE_DEC(tp); 836 tp->t_state = TCPS_TERMINATING; 837 } 838 839 static __inline void 840 TCP_STATE_CHANGE(struct tcpcb *tp, int state) 841 { 842 _TCP_STATE_DEC(tp); 843 _TCP_STATE_SET(tp, state); 844 } 845 846 static __inline void 847 TCP_STATE_MIGRATE_START(const struct tcpcb *tp) 848 { 849 _TCP_STATE_DEC(tp); 850 } 851 852 static __inline void 853 TCP_STATE_MIGRATE_END(const struct tcpcb *tp) 854 { 855 _TCP_STATE_INC(tp); 856 } 857 858 #endif /* _KERNEL */ 859 860 #endif /* _NETINET_TCP_VAR_H_ */ 861