306caafb86
to be no ill effects, and so far as Iknow none of the variables in question depend on 16-bit wraparound behavior. (The sizes are in many cases relics from when a PCB had to fit inside a 128-byte mbuf. PCBs are no longer stored in that way, and the old structure would not have fit, either.)
383 lines
16 KiB
C
383 lines
16 KiB
C
/*
|
|
* 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
|
|
* $Id: tcp_var.h,v 1.17 1995/09/22 07:40:18 peter Exp $
|
|
*/
|
|
|
|
#ifndef _NETINET_TCP_VAR_H_
|
|
#define _NETINET_TCP_VAR_H_
|
|
/*
|
|
* Kernel variables for tcp.
|
|
*/
|
|
|
|
/*
|
|
* Tcp control block, one per tcp; fields:
|
|
*/
|
|
struct tcpcb {
|
|
struct tcpiphdr *seg_next; /* sequencing queue */
|
|
struct tcpiphdr *seg_prev;
|
|
int t_state; /* state of this connection */
|
|
int t_timer[TCPT_NTIMERS]; /* tcp timers */
|
|
int t_rxtshift; /* log(2) of rexmt exp. backoff */
|
|
int t_rxtcur; /* current retransmit value */
|
|
int t_dupacks; /* consecutive dup acks recd */
|
|
u_int t_maxseg; /* maximum segment size */
|
|
u_int t_maxopd; /* mss plus options */
|
|
int t_force; /* 1 if forcing out a byte */
|
|
u_int 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_NEEDSYN 0x0400 /* send SYN (implicit state) */
|
|
#define TF_NEEDFIN 0x0800 /* send FIN (implicit state) */
|
|
#define TF_NOPUSH 0x1000 /* don't push */
|
|
#define TF_REQ_CC 0x2000 /* have/will request CC */
|
|
#define TF_RCVD_CC 0x4000 /* a CC was received in SYN */
|
|
|
|
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 */
|
|
u_long snd_wnd; /* send window */
|
|
/* 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 */
|
|
/*
|
|
* 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
|
|
*/
|
|
/*
|
|
* transmit timing stuff. See below for scale of srtt and rttvar.
|
|
* "Variance" is actually smoothed difference.
|
|
*/
|
|
u_int t_idle; /* inactivity time */
|
|
int t_rtt; /* round trip time */
|
|
tcp_seq t_rtseq; /* sequence number being timed */
|
|
int t_srtt; /* smoothed round-trip time */
|
|
int t_rttvar; /* variance in round-trip time */
|
|
u_int 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
|
|
int 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_long ts_recent; /* timestamp echo data */
|
|
u_long ts_recent_age; /* when last updated */
|
|
tcp_seq last_ack_sent;
|
|
/* RFC 1644 variables */
|
|
tcp_cc cc_send; /* send connection count */
|
|
tcp_cc cc_recv; /* receive connection count */
|
|
u_long t_duration; /* connection duration */
|
|
|
|
/* TUBA stuff */
|
|
caddr_t t_tuba_pcb; /* next level down pcb for TCP over z */
|
|
/* More RTT stuff */
|
|
u_long t_rttupdated; /* number of times rtt sampled */
|
|
};
|
|
|
|
/*
|
|
* Structure to hold TCP options that are only used during segment
|
|
* processing (in tcp_input), but not held in the tcpcb.
|
|
* It's basically used to reduce the number of parameters
|
|
* to tcp_dooptions.
|
|
*/
|
|
struct tcpopt {
|
|
u_long to_flag; /* which options are present */
|
|
#define TOF_TS 0x0001 /* timestamp */
|
|
#define TOF_CC 0x0002 /* CC and CCnew are exclusive */
|
|
#define TOF_CCNEW 0x0004
|
|
#define TOF_CCECHO 0x0008
|
|
u_long to_tsval;
|
|
u_long to_tsecr;
|
|
tcp_cc to_cc; /* holds CC or CCnew */
|
|
tcp_cc to_ccecho;
|
|
};
|
|
|
|
/*
|
|
* The TAO cache entry which is stored in the protocol family specific
|
|
* portion of the route metrics.
|
|
*/
|
|
struct rmxp_tao {
|
|
tcp_cc tao_cc; /* latest CC in valid SYN */
|
|
tcp_cc tao_ccsent; /* latest CC sent to peer */
|
|
u_short tao_mssopt; /* peer's cached MSS */
|
|
#ifdef notyet
|
|
u_short tao_flags; /* cache status flags */
|
|
#define TAOF_DONT 0x0001 /* peer doesn't understand rfc1644 */
|
|
#define TAOF_OK 0x0002 /* peer does understand rfc1644 */
|
|
#define TAOF_UNDEF 0 /* we don't know yet */
|
|
#endif /* notyet */
|
|
};
|
|
#define rmx_taop(r) ((struct rmxp_tao *)(r).rmx_filler)
|
|
|
|
#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 /* shift 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 {
|
|
u_long tcps_connattempt; /* connections initiated */
|
|
u_long tcps_accepts; /* connections accepted */
|
|
u_long tcps_connects; /* connections established */
|
|
u_long tcps_drops; /* connections dropped */
|
|
u_long tcps_conndrops; /* embryonic connections dropped */
|
|
u_long tcps_closed; /* conn. closed (includes drops) */
|
|
u_long tcps_segstimed; /* segs where we tried to get rtt */
|
|
u_long tcps_rttupdated; /* times we succeeded */
|
|
u_long tcps_delack; /* delayed acks sent */
|
|
u_long tcps_timeoutdrop; /* conn. dropped in rxmt timeout */
|
|
u_long tcps_rexmttimeo; /* retransmit timeouts */
|
|
u_long tcps_persisttimeo; /* persist timeouts */
|
|
u_long tcps_keeptimeo; /* keepalive timeouts */
|
|
u_long tcps_keepprobe; /* keepalive probes sent */
|
|
u_long tcps_keepdrops; /* connections dropped in keepalive */
|
|
|
|
u_long tcps_sndtotal; /* total packets sent */
|
|
u_long tcps_sndpack; /* data packets sent */
|
|
u_long tcps_sndbyte; /* data bytes sent */
|
|
u_long tcps_sndrexmitpack; /* data packets retransmitted */
|
|
u_long tcps_sndrexmitbyte; /* data bytes retransmitted */
|
|
u_long tcps_sndacks; /* ack-only packets sent */
|
|
u_long tcps_sndprobe; /* window probes sent */
|
|
u_long tcps_sndurg; /* packets sent with URG only */
|
|
u_long tcps_sndwinup; /* window update-only packets sent */
|
|
u_long tcps_sndctrl; /* control (SYN|FIN|RST) packets sent */
|
|
|
|
u_long tcps_rcvtotal; /* total packets received */
|
|
u_long tcps_rcvpack; /* packets received in sequence */
|
|
u_long tcps_rcvbyte; /* bytes received in sequence */
|
|
u_long tcps_rcvbadsum; /* packets received with ccksum errs */
|
|
u_long tcps_rcvbadoff; /* packets received with bad offset */
|
|
u_long tcps_rcvshort; /* packets received too short */
|
|
u_long tcps_rcvduppack; /* duplicate-only packets received */
|
|
u_long tcps_rcvdupbyte; /* duplicate-only bytes received */
|
|
u_long tcps_rcvpartduppack; /* packets with some duplicate data */
|
|
u_long tcps_rcvpartdupbyte; /* dup. bytes in part-dup. packets */
|
|
u_long tcps_rcvoopack; /* out-of-order packets received */
|
|
u_long tcps_rcvoobyte; /* out-of-order bytes received */
|
|
u_long tcps_rcvpackafterwin; /* packets with data after window */
|
|
u_long tcps_rcvbyteafterwin; /* bytes rcvd after window */
|
|
u_long tcps_rcvafterclose; /* packets rcvd after "close" */
|
|
u_long tcps_rcvwinprobe; /* rcvd window probe packets */
|
|
u_long tcps_rcvdupack; /* rcvd duplicate acks */
|
|
u_long tcps_rcvacktoomuch; /* rcvd acks for unsent data */
|
|
u_long tcps_rcvackpack; /* rcvd ack packets */
|
|
u_long tcps_rcvackbyte; /* bytes acked by rcvd acks */
|
|
u_long tcps_rcvwinupd; /* rcvd window update packets */
|
|
u_long tcps_pawsdrop; /* segments dropped due to PAWS */
|
|
u_long tcps_predack; /* times hdr predict ok for acks */
|
|
u_long tcps_preddat; /* times hdr predict ok for data pkts */
|
|
u_long tcps_pcbcachemiss;
|
|
u_long tcps_cachedrtt; /* times cached RTT in route updated */
|
|
u_long tcps_cachedrttvar; /* times cached rttvar updated */
|
|
u_long tcps_cachedssthresh; /* times cached ssthresh updated */
|
|
u_long tcps_usedrtt; /* times RTT initialized from route */
|
|
u_long tcps_usedrttvar; /* times RTTVAR initialized from rt */
|
|
u_long tcps_usedssthresh; /* times ssthresh initialized from rt*/
|
|
u_long tcps_persistdrop; /* timeout in persist state */
|
|
u_long tcps_badsyn; /* bogus SYN, e.g. premature ACK */
|
|
};
|
|
|
|
/*
|
|
* Names for TCP sysctl objects
|
|
*/
|
|
#define TCPCTL_DO_RFC1323 1 /* use RFC-1323 extensions */
|
|
#define TCPCTL_DO_RFC1644 2 /* use RFC-1644 extensions */
|
|
#define TCPCTL_MSSDFLT 3 /* MSS default */
|
|
#define TCPCTL_STATS 4 /* statistics (read-only) */
|
|
#define TCPCTL_RTTDFLT 5 /* default RTT estimate */
|
|
#define TCPCTL_KEEPIDLE 6 /* keepalive idle timer */
|
|
#define TCPCTL_KEEPINTVL 7 /* interval to send keepalives */
|
|
#define TCPCTL_SENDSPACE 8 /* send buffer space */
|
|
#define TCPCTL_RECVSPACE 9 /* receive buffer space */
|
|
#define TCPCTL_MAXID 10
|
|
|
|
#define TCPCTL_NAMES { \
|
|
{ 0, 0 }, \
|
|
{ "rfc1323", CTLTYPE_INT }, \
|
|
{ "rfc1644", CTLTYPE_INT }, \
|
|
{ "mssdflt", CTLTYPE_INT }, \
|
|
{ "stats", CTLTYPE_STRUCT }, \
|
|
{ "rttdflt", CTLTYPE_INT }, \
|
|
{ "keepidle", CTLTYPE_INT }, \
|
|
{ "keepintvl", CTLTYPE_INT }, \
|
|
{ "sendspace", CTLTYPE_INT }, \
|
|
{ "recvspace", CTLTYPE_INT }, \
|
|
}
|
|
|
|
#ifdef KERNEL
|
|
extern struct inpcbhead tcb; /* head of queue of active tcpcb's */
|
|
extern struct inpcbinfo tcbinfo;
|
|
extern struct tcpstat tcpstat; /* tcp statistics */
|
|
extern int tcp_do_rfc1323; /* XXX */
|
|
extern int tcp_do_rfc1644; /* XXX */
|
|
extern int tcp_mssdflt; /* XXX */
|
|
extern u_long tcp_now; /* for RFC 1323 timestamps */
|
|
extern int tcp_rttdflt; /* XXX */
|
|
extern u_short tcp_lastport; /* last assigned port */
|
|
|
|
int tcp_attach __P((struct socket *));
|
|
void tcp_canceltimers __P((struct tcpcb *));
|
|
struct tcpcb *
|
|
tcp_close __P((struct tcpcb *));
|
|
int tcp_connect __P((struct tcpcb *, struct mbuf *));
|
|
void tcp_ctlinput __P((int, struct sockaddr *, struct ip *));
|
|
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 tcpiphdr *, struct tcpopt *));
|
|
void tcp_drain __P((void));
|
|
void tcp_fasttimo __P((void));
|
|
struct rmxp_tao *
|
|
tcp_gettaocache __P((struct inpcb *));
|
|
void tcp_init __P((void));
|
|
void tcp_input __P((struct mbuf *, int));
|
|
void tcp_mss __P((struct tcpcb *, int));
|
|
int tcp_mssopt __P((struct tcpcb *));
|
|
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 *,
|
|
struct tcpiphdr *, struct mbuf *));
|
|
void tcp_quench __P((struct inpcb *, int));
|
|
int tcp_reass __P((struct tcpcb *, struct tcpiphdr *, struct mbuf *));
|
|
void tcp_respond __P((struct tcpcb *,
|
|
struct tcpiphdr *, struct mbuf *, u_long, u_long, int));
|
|
struct rtentry *
|
|
tcp_rtlookup __P((struct inpcb *));
|
|
void tcp_setpersist __P((struct tcpcb *));
|
|
void tcp_slowtimo __P((void));
|
|
int tcp_sysctl __P((int *, u_int, void *, size_t *, void *, size_t));
|
|
struct tcpiphdr *
|
|
tcp_template __P((struct tcpcb *));
|
|
struct tcpcb *
|
|
tcp_timers __P((struct tcpcb *, int));
|
|
void tcp_trace __P((int, int, struct tcpcb *, struct tcpiphdr *, int));
|
|
struct tcpcb *
|
|
tcp_usrclosed __P((struct tcpcb *));
|
|
int tcp_usrreq __P((struct socket *,
|
|
int, struct mbuf *, struct mbuf *, struct mbuf *));
|
|
void tcp_xmit_timer __P((struct tcpcb *, int));
|
|
|
|
extern u_long tcp_sendspace;
|
|
extern u_long tcp_recvspace;
|
|
|
|
#endif /* KERNEL */
|
|
|
|
#endif /* _NETINET_TCP_VAR_H_ */
|