-/*
- * Copyright (c) 1982, 1986, 1993, 1994, 1995
- * 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 8.4 (Berkeley) 5/24/95
- */
-
-/*
- * Kernel variables for tcp.
- */
-
-/*
- * Tcp control block, one per tcp; fields:
- */
-struct tcpcb {
- struct tcpiphdr *seg_next; /* sequencing queue */
- struct tcpiphdr *seg_prev;
- 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 */
-
- struct tcpiphdr *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 */
- n_long snd_wnd; /* send window */
-/* receive sequence variables */
- n_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 */
-/*
- * 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) */
- n_long snd_cwnd; /* congestion-controlled window */
- n_long snd_ssthresh; /* snd_cwnd size threshhold for
- * for slow start exponential to
- * linear switch
- */
-/*
- * transmit timing stuff. See below for scale of srtt and rttvar.
- * "Variance" is actually smoothed difference.
- */
- u_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 */
- n_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;
- n_long ts_recent; /* timestamp echo data */
- n_long 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 */
-};
-
-#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)
-
-/* XXX
- * We want to avoid doing m_pullup on incoming packets but that
- * means avoiding dtom on the tcp reassembly code. That in turn means
- * keeping an mbuf pointer in the reassembly queue (since we might
- * have a cluster). As a quick hack, the source & destination
- * port numbers (which are no longer needed once we've located the
- * tcpcb) are overlayed with an mbuf pointer.
- */
-#define REASS_MBUF(ti) (*(struct mbuf **)&((ti)->ti_t))
-
-/*
- * TCP statistics.
- * Many of these should be kept per connection,
- * but that's inconvenient at the moment.
- */
-struct tcpstat {
- n_long tcps_connattempt; /* connections initiated */
- n_long tcps_accepts; /* connections accepted */
- n_long tcps_connects; /* connections established */
- n_long tcps_drops; /* connections dropped */
- n_long tcps_conndrops; /* embryonic connections dropped */
- n_long tcps_closed; /* conn. closed (includes drops) */
- n_long tcps_segstimed; /* segs where we tried to get rtt */
- n_long tcps_rttupdated; /* times we succeeded */
- n_long tcps_delack; /* delayed acks sent */
- n_long tcps_timeoutdrop; /* conn. dropped in rxmt timeout */
- n_long tcps_rexmttimeo; /* retransmit timeouts */
- n_long tcps_persisttimeo; /* persist timeouts */
- n_long tcps_keeptimeo; /* keepalive timeouts */
- n_long tcps_keepprobe; /* keepalive probes sent */
- n_long tcps_keepdrops; /* connections dropped in keepalive */
-
- n_long tcps_sndtotal; /* total packets sent */
- n_long tcps_sndpack; /* data packets sent */
- n_long tcps_sndbyte; /* data bytes sent */
- n_long tcps_sndrexmitpack; /* data packets retransmitted */
- n_long tcps_sndrexmitbyte; /* data bytes retransmitted */
- n_long tcps_sndacks; /* ack-only packets sent */
- n_long tcps_sndprobe; /* window probes sent */
- n_long tcps_sndurg; /* packets sent with URG only */
- n_long tcps_sndwinup; /* window update-only packets sent */
- n_long tcps_sndctrl; /* control (SYN|FIN|RST) packets sent */
-
- n_long tcps_rcvtotal; /* total packets received */
- n_long tcps_rcvpack; /* packets received in sequence */
- n_long tcps_rcvbyte; /* bytes received in sequence */
- n_long tcps_rcvbadsum; /* packets received with ccksum errs */
- n_long tcps_rcvbadoff; /* packets received with bad offset */
- n_long tcps_rcvshort; /* packets received too short */
- n_long tcps_rcvduppack; /* duplicate-only packets received */
- n_long tcps_rcvdupbyte; /* duplicate-only bytes received */
- n_long tcps_rcvpartduppack; /* packets with some duplicate data */
- n_long tcps_rcvpartdupbyte; /* dup. bytes in part-dup. packets */
- n_long tcps_rcvoopack; /* out-of-order packets received */
- n_long tcps_rcvoobyte; /* out-of-order bytes received */
- n_long tcps_rcvpackafterwin; /* packets with data after window */
- n_long tcps_rcvbyteafterwin; /* bytes rcvd after window */
- n_long tcps_rcvafterclose; /* packets rcvd after "close" */
- n_long tcps_rcvwinprobe; /* rcvd window probe packets */
- n_long tcps_rcvdupack; /* rcvd duplicate acks */
- n_long tcps_rcvacktoomuch; /* rcvd acks for unsent data */
- n_long tcps_rcvackpack; /* rcvd ack packets */
- n_long tcps_rcvackbyte; /* bytes acked by rcvd acks */
- n_long tcps_rcvwinupd; /* rcvd window update packets */
- n_long tcps_pawsdrop; /* segments dropped due to PAWS */
- n_long tcps_predack; /* times hdr predict ok for acks */
- n_long tcps_preddat; /* times hdr predict ok for data pkts */
- n_long tcps_pcbcachemiss;
- n_long tcps_persistdrop; /* timeout in persist state */
- n_long tcps_badsyn; /* bogus SYN, e.g. premature ACK */
-};
-
-#ifdef KERNEL
-struct inpcb tcb; /* head of queue of active tcpcb's */
-struct tcpstat tcpstat; /* tcp statistics */
-n_long tcp_now; /* for RFC 1323 timestamps */
-
-int tcp_attach (struct socket *);
-void tcp_canceltimers (struct tcpcb *);
-struct tcpcb *
- tcp_close (struct tcpcb *);
-void tcp_ctlinput (int, struct sockaddr *, struct ip *);
-int tcp_ctloutput (int, struct socket *, int, int, struct mbuf **);
-struct tcpcb *
- tcp_disconnect (struct tcpcb *);
-struct tcpcb *
- tcp_drop (struct tcpcb *, int);
-void tcp_dooptions (struct tcpcb *,
- u_char *, int, struct tcpiphdr *, int *, n_long *, n_long *);
-void tcp_drain (void);
-void tcp_fasttimo (void);
-void tcp_init (void);
-void tcp_input (struct mbuf *, int);
-int tcp_mss (struct tcpcb *, u_int);
-struct tcpcb *
- tcp_newtcpcb (struct inpcb *);
-void tcp_notify (struct inpcb *, int);
-int tcp_output (struct tcpcb *);
-void tcp_pulloutofband (struct socket *,
- struct tcpiphdr *, struct mbuf *);
-void tcp_quench (struct inpcb *, int);
-int tcp_reass (struct tcpcb *, struct tcpiphdr *, struct mbuf *);
-void tcp_respond (struct tcpcb *,
- struct tcpiphdr *, struct mbuf *, n_long, n_long, int);
-void tcp_setpersist (struct tcpcb *);
-void tcp_slowtimo (void);
-struct tcpiphdr *
- tcp_template (struct tcpcb *);
-struct tcpcb *
- tcp_timers (struct tcpcb *, int);
-void tcp_trace (int, int, struct tcpcb *, struct tcpiphdr *, int);
-struct tcpcb *
- tcp_usrclosed (struct tcpcb *);
-int tcp_usrreq (struct socket *,
- int, struct mbuf *, struct mbuf *, struct mbuf *);
-void tcp_xmit_timer (struct tcpcb *, int);
-#endif
projects / tcpdump / commitdiff
