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/* $OpenBSD: tcp_var.h,v 1.32 2000/09/25 09:41:03 provos Exp $ */
/* $NetBSD: tcp_var.h,v 1.17 1996/02/13 23:44:24 christos Exp $ */
/*
* Copyright (c) 1982, 1986, 1993, 1994
* The Regents of the University of California. All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* 3. All advertising materials mentioning features or use of this software
* must display the following acknowledgement:
* This product includes software developed by the University of
* California, Berkeley and its contributors.
* 4. Neither the name of the University nor the names of its contributors
* may be used to endorse or promote products derived from this software
* without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*
* @(#)tcp_var.h 8.3 (Berkeley) 4/10/94
*/
struct sackblk {
tcp_seq start; /* start seq no. of sack block */
tcp_seq end; /* end seq no. */
};
struct sackhole {
tcp_seq start; /* start seq no. of hole */
tcp_seq end; /* end seq no. */
int dups; /* number of dup(s)acks for this hole */
tcp_seq rxmit; /* next seq. no in hole to be retransmitted */
struct sackhole *next; /* next in list */
};
/*
* Kernel variables for tcp.
*/
/*
* Tcp control block, one per tcp; fields:
*/
struct tcpcb {
struct ipqehead segq; /* sequencing queue */
short t_state; /* state of this connection */
short t_timer[TCPT_NTIMERS]; /* tcp timers */
short t_rxtshift; /* log(2) of rexmt exp. backoff */
short t_rxtcur; /* current retransmit value */
short t_dupacks; /* consecutive dup acks recd */
u_short t_maxseg; /* maximum segment size */
char t_force; /* 1 if forcing out a byte */
u_short t_flags;
#define TF_ACKNOW 0x0001 /* ack peer immediately */
#define TF_DELACK 0x0002 /* ack, but try to delay it */
#define TF_NODELAY 0x0004 /* don't delay packets to coalesce */
#define TF_NOOPT 0x0008 /* don't use tcp options */
#define TF_SENTFIN 0x0010 /* have sent FIN */
#define TF_REQ_SCALE 0x0020 /* have/will request window scaling */
#define TF_RCVD_SCALE 0x0040 /* other side has requested scaling */
#define TF_REQ_TSTMP 0x0080 /* have/will request timestamps */
#define TF_RCVD_TSTMP 0x0100 /* a timestamp was received in SYN */
#define TF_SACK_PERMIT 0x0200 /* other side said I could SACK */
#define TF_SIGNATURE 0x0400 /* require TCP MD5 signature */
struct mbuf *t_template; /* skeletal packet for transmit */
struct inpcb *t_inpcb; /* back pointer to internet pcb */
/*
* The following fields are used as in the protocol specification.
* See RFC783, Dec. 1981, page 21.
*/
/* send sequence variables */
tcp_seq snd_una; /* send unacknowledged */
tcp_seq snd_nxt; /* send next */
tcp_seq snd_up; /* send urgent pointer */
tcp_seq snd_wl1; /* window update seg seq number */
tcp_seq snd_wl2; /* window update seg ack number */
tcp_seq iss; /* initial send sequence number */
u_long snd_wnd; /* send window */
#ifdef TCP_SACK
int sack_disable; /* disable SACK for this connection */
int snd_numholes; /* number of holes seen by sender */
struct sackhole *snd_holes; /* linked list of holes (sorted) */
#if defined(TCP_SACK) && defined(TCP_FACK)
tcp_seq snd_fack; /* for FACK congestion control */
u_long snd_awnd; /* snd_nxt - snd_fack + */
/* retransmitted data */
int retran_data; /* amount of outstanding retx. data */
#endif /* TCP_FACK */
#endif /* TCP_SACK */
#if defined(TCP_SACK)
tcp_seq snd_last; /* for use in fast recovery */
#endif
/* receive sequence variables */
u_long rcv_wnd; /* receive window */
tcp_seq rcv_nxt; /* receive next */
tcp_seq rcv_up; /* receive urgent pointer */
tcp_seq irs; /* initial receive sequence number */
#ifdef TCP_SACK
tcp_seq rcv_laststart; /* start of last segment recd. */
tcp_seq rcv_lastend; /* end of ... */
tcp_seq rcv_lastsack; /* last seq number(+1) sack'd by rcv'r*/
int rcv_numsacks; /* # distinct sack blks present */
struct sackblk sackblks[MAX_SACK_BLKS]; /* seq nos. of sack blocks */
#endif
/*
* Additional variables for this implementation.
*/
/* receive variables */
tcp_seq rcv_adv; /* advertised window */
/* retransmit variables */
tcp_seq snd_max; /* highest sequence number sent;
* used to recognize retransmits
*/
/* congestion control (for slow start, source quench, retransmit after loss) */
u_long snd_cwnd; /* congestion-controlled window */
u_long snd_ssthresh; /* snd_cwnd size threshhold for
* for slow start exponential to
* linear switch
*/
u_short t_maxopd; /* mss plus options */
u_short t_peermss; /* peer's maximum segment size */
/*
* transmit timing stuff. See below for scale of srtt and rttvar.
* "Variance" is actually smoothed difference.
*/
short t_idle; /* inactivity time */
short t_rtt; /* round trip time */
tcp_seq t_rtseq; /* sequence number being timed */
short t_srtt; /* smoothed round-trip time */
short t_rttvar; /* variance in round-trip time */
u_short t_rttmin; /* minimum rtt allowed */
u_long max_sndwnd; /* largest window peer has offered */
/* out-of-band data */
char t_oobflags; /* have some */
char t_iobc; /* input character */
#define TCPOOB_HAVEDATA 0x01
#define TCPOOB_HADDATA 0x02
short t_softerror; /* possible error not yet reported */
/* RFC 1323 variables */
u_char snd_scale; /* window scaling for send window */
u_char rcv_scale; /* window scaling for recv window */
u_char request_r_scale; /* pending window scaling */
u_char requested_s_scale;
u_int32_t ts_recent; /* timestamp echo data */
u_int32_t ts_recent_age; /* when last updated */
tcp_seq last_ack_sent;
/* TUBA stuff */
caddr_t t_tuba_pcb; /* next level down pcb for TCP over z */
int pf;
};
#define intotcpcb(ip) ((struct tcpcb *)(ip)->inp_ppcb)
#define sototcpcb(so) (intotcpcb(sotoinpcb(so)))
/*
* The smoothed round-trip time and estimated variance
* are stored as fixed point numbers scaled by the values below.
* For convenience, these scales are also used in smoothing the average
* (smoothed = (1/scale)sample + ((scale-1)/scale)smoothed).
* With these scales, srtt has 3 bits to the right of the binary point,
* and thus an "ALPHA" of 0.875. rttvar has 2 bits to the right of the
* binary point, and is smoothed with an ALPHA of 0.75.
*/
#define TCP_RTT_SCALE 8 /* multiplier for srtt; 3 bits frac. */
#define TCP_RTT_SHIFT 3 /* shift for srtt; 3 bits frac. */
#define TCP_RTTVAR_SCALE 4 /* multiplier for rttvar; 2 bits */
#define TCP_RTTVAR_SHIFT 2 /* multiplier for rttvar; 2 bits */
/*
* The initial retransmission should happen at rtt + 4 * rttvar.
* Because of the way we do the smoothing, srtt and rttvar
* will each average +1/2 tick of bias. When we compute
* the retransmit timer, we want 1/2 tick of rounding and
* 1 extra tick because of +-1/2 tick uncertainty in the
* firing of the timer. The bias will give us exactly the
* 1.5 tick we need. But, because the bias is
* statistical, we have to test that we don't drop below
* the minimum feasible timer (which is 2 ticks).
* This macro assumes that the value of TCP_RTTVAR_SCALE
* is the same as the multiplier for rttvar.
*/
#define TCP_REXMTVAL(tp) \
((((tp)->t_srtt >> TCP_RTT_SHIFT) + (tp)->t_rttvar) >> 2)
/*
* TCP statistics.
* Many of these should be kept per connection,
* but that's inconvenient at the moment.
*/
struct tcpstat {
u_int32_t tcps_connattempt; /* connections initiated */
u_int32_t tcps_accepts; /* connections accepted */
u_int32_t tcps_connects; /* connections established */
u_int32_t tcps_drops; /* connections dropped */
u_int32_t tcps_conndrops; /* embryonic connections dropped */
u_int32_t tcps_closed; /* conn. closed (includes drops) */
u_int32_t tcps_segstimed; /* segs where we tried to get rtt */
u_int32_t tcps_rttupdated; /* times we succeeded */
u_int32_t tcps_delack; /* delayed acks sent */
u_int32_t tcps_timeoutdrop; /* conn. dropped in rxmt timeout */
u_int32_t tcps_rexmttimeo; /* retransmit timeouts */
u_int32_t tcps_persisttimeo; /* persist timeouts */
u_int32_t tcps_persistdrop; /* connections dropped in persist */
u_int32_t tcps_keeptimeo; /* keepalive timeouts */
u_int32_t tcps_keepprobe; /* keepalive probes sent */
u_int32_t tcps_keepdrops; /* connections dropped in keepalive */
u_int32_t tcps_sndtotal; /* total packets sent */
u_int32_t tcps_sndpack; /* data packets sent */
u_int64_t tcps_sndbyte; /* data bytes sent */
u_int32_t tcps_sndrexmitpack; /* data packets retransmitted */
u_int64_t tcps_sndrexmitbyte; /* data bytes retransmitted */
u_int64_t tcps_sndrexmitfast; /* Fast retransmits */
u_int32_t tcps_sndacks; /* ack-only packets sent */
u_int32_t tcps_sndprobe; /* window probes sent */
u_int32_t tcps_sndurg; /* packets sent with URG only */
u_int32_t tcps_sndwinup; /* window update-only packets sent */
u_int32_t tcps_sndctrl; /* control (SYN|FIN|RST) packets sent */
u_int32_t tcps_rcvtotal; /* total packets received */
u_int32_t tcps_rcvpack; /* packets received in sequence */
u_int64_t tcps_rcvbyte; /* bytes received in sequence */
u_int32_t tcps_rcvbadsum; /* packets received with ccksum errs */
u_int32_t tcps_rcvbadoff; /* packets received with bad offset */
u_int32_t tcps_rcvmemdrop; /* packets dropped for lack of memory */
u_int32_t tcps_rcvnosec; /* packets dropped for lack of ipsec */
u_int32_t tcps_rcvshort; /* packets received too short */
u_int32_t tcps_rcvduppack; /* duplicate-only packets received */
u_int64_t tcps_rcvdupbyte; /* duplicate-only bytes received */
u_int32_t tcps_rcvpartduppack; /* packets with some duplicate data */
u_int64_t tcps_rcvpartdupbyte; /* dup. bytes in part-dup. packets */
u_int32_t tcps_rcvoopack; /* out-of-order packets received */
u_int64_t tcps_rcvoobyte; /* out-of-order bytes received */
u_int32_t tcps_rcvpackafterwin; /* packets with data after window */
u_int64_t tcps_rcvbyteafterwin; /* bytes rcvd after window */
u_int32_t tcps_rcvafterclose; /* packets rcvd after "close" */
u_int32_t tcps_rcvwinprobe; /* rcvd window probe packets */
u_int32_t tcps_rcvdupack; /* rcvd duplicate acks */
u_int32_t tcps_rcvacktoomuch; /* rcvd acks for unsent data */
u_int32_t tcps_rcvackpack; /* rcvd ack packets */
u_int64_t tcps_rcvackbyte; /* bytes acked by rcvd acks */
u_int32_t tcps_rcvwinupd; /* rcvd window update packets */
u_int32_t tcps_pawsdrop; /* segments dropped due to PAWS */
u_int32_t tcps_predack; /* times hdr predict ok for acks */
u_int32_t tcps_preddat; /* times hdr predict ok for data pkts */
u_int32_t tcps_pcbhashmiss; /* input packets missing pcb hash */
u_int32_t tcps_noport; /* no socket on port */
u_int32_t tcps_badsyn; /* SYN packet with src==dst rcv'ed */
u_int32_t tcps_rcvbadsig; /* rcvd bad/missing TCP signatures */
u_int64_t tcps_rcvgoodsig; /* rcvd good TCP signatures */
};
/*
* Names for TCP sysctl objects.
*/
#define TCPCTL_RFC1323 1 /* enable/disable RFC1323 timestamps/scaling */
#define TCPCTL_KEEPINITTIME 2 /* TCPT_KEEP value */
#define TCPCTL_KEEPIDLE 3 /* allow tcp_keepidle to be changed */
#define TCPCTL_KEEPINTVL 4 /* allow tcp_keepintvl to be changed */
#define TCPCTL_SLOWHZ 5 /* return kernel idea of PR_SLOWHZ */
#define TCPCTL_BADDYNAMIC 6 /* return bad dynamic port bitmap */
#define TCPCTL_RECVSPACE 7 /* receive buffer space */
#define TCPCTL_SENDSPACE 8 /* send buffer space */
#define TCPCTL_IDENT 9 /* get connection owner */
#define TCPCTL_SACK 10 /* selective acknowledgement, rfc 2018 */
#define TCPCTL_MSSDFLT 11 /* Default maximum segment size */
#define TCPCTL_MAXID 12
#define TCPCTL_NAMES { \
{ 0, 0 }, \
{ "rfc1323", CTLTYPE_INT }, \
{ "keepinittime", CTLTYPE_INT }, \
{ "keepidle", CTLTYPE_INT }, \
{ "keepintvl", CTLTYPE_INT }, \
{ "slowhz", CTLTYPE_INT }, \
{ "baddynamic", CTLTYPE_STRUCT }, \
{ "recvspace", CTLTYPE_INT }, \
{ "sendspace", CTLTYPE_INT }, \
{ "ident", CTLTYPE_STRUCT }, \
{ "sack", CTLTYPE_INT }, \
{ "mssdflt", CTLTYPE_INT }, \
}
struct tcp_ident_mapping {
struct sockaddr_storage faddr, laddr;
int euid, ruid;
};
#ifdef _KERNEL
struct inpcbtable tcbtable; /* head of queue of active tcpcb's */
extern struct tcpstat tcpstat; /* tcp statistics */
u_int32_t tcp_now; /* for RFC 1323 timestamps */
extern int tcp_do_rfc1323; /* enabled/disabled? */
extern int tcp_mssdflt; /* default maximum segment size */
#ifdef TCP_SACK
extern int tcp_do_sack; /* SACK enabled/disabled */
#endif
int tcp_attach __P((struct socket *));
void tcp_canceltimers __P((struct tcpcb *));
struct tcpcb *
tcp_close __P((struct tcpcb *));
#if defined(INET6) && !defined(TCP6)
void tcp6_ctlinput __P((int, struct sockaddr *, void *));
#endif
void *tcp_ctlinput __P((int, struct sockaddr *, void *));
int tcp_ctloutput __P((int, struct socket *, int, int, struct mbuf **));
struct tcpcb *
tcp_disconnect __P((struct tcpcb *));
struct tcpcb *
tcp_drop __P((struct tcpcb *, int));
void tcp_dooptions __P((struct tcpcb *, u_char *, int, struct tcphdr *,
int *, u_int32_t *, u_int32_t *));
void tcp_drain __P((void));
void tcp_fasttimo __P((void));
void tcp_init __P((void));
#if defined(INET6) && !defined(TCP6)
int tcp6_input __P((struct mbuf **, int *, int));
#endif
void tcp_input __P((struct mbuf *, ...));
int tcp_mss __P((struct tcpcb *, int));
void tcp_mss_update __P((struct tcpcb *));
void tcp_mtudisc __P((struct inpcb *, int));
void tcp_mtudisc_increase __P((struct inpcb *, int));
struct tcpcb *
tcp_newtcpcb __P((struct inpcb *));
void tcp_notify __P((struct inpcb *, int));
int tcp_output __P((struct tcpcb *));
void tcp_pulloutofband __P((struct socket *, u_int, struct mbuf *, int));
void tcp_quench __P((struct inpcb *, int));
int tcp_reass __P((struct tcpcb *, struct tcphdr *, struct mbuf *, int *));
void tcp_rscale __P((struct tcpcb *, u_long));
void tcp_respond __P((struct tcpcb *, caddr_t, struct mbuf *, tcp_seq,
tcp_seq, int));
void tcp_setpersist __P((struct tcpcb *));
void tcp_slowtimo __P((void));
struct mbuf *
tcp_template __P((struct tcpcb *));
struct tcpcb *
tcp_timers __P((struct tcpcb *, int));
void tcp_trace __P((int, int, struct tcpcb *, caddr_t, int, int));
struct tcpcb *
tcp_usrclosed __P((struct tcpcb *));
int tcp_sysctl __P((int *, u_int, void *, size_t *, void *, size_t));
#if defined(INET6) && !defined(TCP6)
int tcp6_usrreq __P((struct socket *,
int, struct mbuf *, struct mbuf *, struct mbuf *, struct proc *));
#endif
int tcp_usrreq __P((struct socket *,
int, struct mbuf *, struct mbuf *, struct mbuf *));
void tcp_xmit_timer __P((struct tcpcb *, int));
void tcpdropoldhalfopen __P((struct tcpcb *, u_int16_t));
#ifdef TCP_SACK
int tcp_sack_option __P((struct tcpcb *,struct tcphdr *,u_char *,int));
void tcp_update_sack_list __P((struct tcpcb *tp));
void tcp_del_sackholes __P((struct tcpcb *, struct tcphdr *));
void tcp_clean_sackreport __P((struct tcpcb *tp));
void tcp_sack_adjust __P((struct tcpcb *tp));
struct sackhole *
tcp_sack_output __P((struct tcpcb *tp));
int tcp_sack_partialack __P((struct tcpcb *, struct tcphdr *));
#ifdef DEBUG
void tcp_print_holes __P((struct tcpcb *tp));
#endif
#endif /* TCP_SACK */
#if defined(TCP_SACK)
int tcp_newreno __P((struct tcpcb *, struct tcphdr *));
u_long tcp_seq_subtract __P((u_long, u_long ));
#endif /* TCP_SACK */
#ifdef TCP_SIGNATURE
int tcp_signature_apply __P((caddr_t, caddr_t, unsigned int));
#endif /* TCP_SIGNATURE */
#endif /* _KERNEL */
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