/* * Copyright (c) 2000 Apple Computer, Inc. All rights reserved. * * @APPLE_LICENSE_HEADER_START@ * * The contents of this file constitute Original Code as defined in and * are subject to the Apple Public Source License Version 1.1 (the * "License"). You may not use this file except in compliance with the * License. Please obtain a copy of the License at * http://www.apple.com/publicsource and read it before using this file. * * This Original Code and all software distributed under the License are * distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY KIND, EITHER * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES, * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY, * FITNESS FOR A PARTICULAR PURPOSE OR NON-INFRINGEMENT. Please see the * License for the specific language governing rights and limitations * under the License. * * @APPLE_LICENSE_HEADER_END@ */ /* * 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 */ #ifndef _NETINET_TCP_VAR_H_ #define _NETINET_TCP_VAR_H_ #define N_TIME_WAIT_SLOTS 128 /* must be power of 2 */ /* * Ip (reassembly or sequence) queue structures. * * XXX -- The following explains why the ipqe_m field is here, for TCP's use: * 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. */ LIST_HEAD(ipqehead, ipqent); struct ipqent { LIST_ENTRY(ipqent) ipqe_q; union { struct ip *_ip; #if INET6 struct ipv6 *_ip6; #endif struct tcpiphdr *_tcp; } _ipqe_u1; struct mbuf *ipqe_m; /* mbuf contains packet */ u_int8_t ipqe_mff; /* for IP fragmentation */ }; #define ipqe_ip _ipqe_u1._ip #if INET6 #define ipqe_ip6 _ipqe_u1._ip6 #endif #define ipqe_tcp _ipqe_u1._tcp #define tcp6cb tcpcb /* for KAME src sync over BSD*'s */ #define TCP_DELACK_BITSET(hash_elem)\ delack_bitmask[((hash_elem) >> 5)] |= 1 << ((hash_elem) & 0x1F) #define DELACK_BITMASK_ON 1 #define DELACK_BITMASK_THRESH 300 /* * Kernel variables for tcp. */ /* * Tcp control block, one per tcp; fields: * Organized for 16 byte cacheline efficiency. */ struct tcpcb { struct ipqehead segq; /* sequencing queue */ int t_dupacks; /* consecutive dup acks recd */ struct tcptemp *t_template; /* skeletal packet for transmit */ int t_timer[TCPT_NTIMERS]; /* tcp timers */ struct inpcb *t_inpcb; /* back pointer to internet pcb */ int t_state; /* state of this connection */ u_int t_flags; #define TF_ACKNOW 0x00001 /* ack peer immediately */ #define TF_DELACK 0x00002 /* ack, but try to delay it */ #define TF_NODELAY 0x00004 /* don't delay packets to coalesce */ #define TF_NOOPT 0x00008 /* don't use tcp options */ #define TF_SENTFIN 0x00010 /* have sent FIN */ #define TF_REQ_SCALE 0x00020 /* have/will request window scaling */ #define TF_RCVD_SCALE 0x00040 /* other side has requested scaling */ #define TF_REQ_TSTMP 0x00080 /* have/will request timestamps */ #define TF_RCVD_TSTMP 0x00100 /* a timestamp was received in SYN */ #define TF_SACK_PERMIT 0x00200 /* other side said I could SACK */ #define TF_NEEDSYN 0x00400 /* send SYN (implicit state) */ #define TF_NEEDFIN 0x00800 /* send FIN (implicit state) */ #define TF_NOPUSH 0x01000 /* don't push */ #define TF_REQ_CC 0x02000 /* have/will request CC */ #define TF_RCVD_CC 0x04000 /* a CC was received in SYN */ #define TF_SENDCCNEW 0x08000 /* send CCnew instead of CC in SYN */ #define TF_MORETOCOME 0x10000 /* More data to be appended to sock */ int t_force; /* 1 if forcing out a byte */ tcp_seq snd_una; /* send unacknowledged */ tcp_seq snd_max; /* highest sequence number sent; * used to recognize retransmits */ 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 */ tcp_seq irs; /* initial receive sequence number */ tcp_seq rcv_nxt; /* receive next */ tcp_seq rcv_adv; /* advertised window */ u_long rcv_wnd; /* receive window */ tcp_seq rcv_up; /* receive urgent pointer */ u_long snd_wnd; /* send window */ u_long snd_cwnd; /* congestion-controlled window */ u_long snd_ssthresh; /* snd_cwnd size threshold for * for slow start exponential to * linear switch */ u_int t_maxopd; /* mss plus options */ u_int t_idle; /* inactivity time */ u_long t_duration; /* connection duration */ int t_rtt; /* round trip time */ tcp_seq t_rtseq; /* sequence number being timed */ int t_rxtcur; /* current retransmit value */ u_int t_maxseg; /* maximum segment size */ int t_srtt; /* smoothed round-trip time */ int t_rttvar; /* variance in round-trip time */ int t_rxtshift; /* log(2) of rexmt exp. backoff */ u_int t_rttmin; /* minimum rtt allowed */ u_long t_rttupdated; /* number of times rtt sampled */ u_long max_sndwnd; /* largest window peer has offered */ int t_softerror; /* possible error not yet reported */ /* out-of-band data */ char t_oobflags; /* have some */ char t_iobc; /* input character */ #define TCPOOB_HAVEDATA 0x01 #define TCPOOB_HADDATA 0x02 /* 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 */ }; /* * 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; u_short to_maxseg; }; /* * 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 32 /* multiplier for srtt; 3 bits frac. */ #define TCP_RTT_SHIFT 5 /* shift for srtt; 3 bits frac. */ #define TCP_RTTVAR_SCALE 16 /* multiplier for rttvar; 2 bits */ #define TCP_RTTVAR_SHIFT 4 /* shift for rttvar; 2 bits */ #define TCP_DELTA_SHIFT 2 /* see tcp_input.c */ /* * 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 version of the macro adapted from a paper by Lawrence * Brakmo and Larry Peterson which outlines a problem caused * by insufficient precision in the original implementation, * which results in inappropriately large RTO values for very * fast networks. */ #define TCP_REXMTVAL(tp) \ max((tp)->t_rttmin, (((tp)->t_srtt >> (TCP_RTT_SHIFT - TCP_DELTA_SHIFT)) \ + (tp)->t_rttvar) >> TCP_DELTA_SHIFT) /* * 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_rcvmemdrop; /* packets dropped for lack of memory */ 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 */ u_long tcps_mturesent; /* resends due to MTU discovery */ u_long tcps_listendrop; /* listen queue overflows */ }; /* * TCB structure exported to user-land via sysctl(3). * Evil hack: declare only if in_pcb.h and sys/socketvar.h have been * included. Not all of our clients do. */ #if defined(_NETINET_IN_PCB_H_) && defined(_SYS_SOCKETVAR_H_) struct xtcpcb { size_t xt_len; struct inpcb xt_inp; struct tcpcb xt_tp; struct xsocket xt_socket; u_quad_t xt_alignment_hack; }; #endif /* * 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_KEEPINIT 10 /* receive buffer space */ #define TCPCTL_PCBLIST 11 /* list of all outstanding PCBs */ #define TCPCTL_V6MSSDFLT 12 /* MSS default for IPv6 */ #define TCPCTL_MAXID 13 #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 }, \ { "keepinit", CTLTYPE_INT }, \ { "pcblist", CTLTYPE_STRUCT }, \ { "v6mssdflt", CTLTYPE_INT }, \ } #ifdef KERNEL #ifdef SYSCTL_DECL SYSCTL_DECL(_net_inet_tcp); #endif extern struct inpcbhead tcb; /* head of queue of active tcpcb's */ extern struct inpcbinfo tcbinfo; extern struct tcpstat tcpstat; /* tcp statistics */ extern int tcp_mssdflt; /* XXX */ extern int tcp_v6mssdflt; /* XXX */ extern u_long tcp_now; /* for RFC 1323 timestamps */ extern int tcp_delack_enabled; void tcp_canceltimers __P((struct tcpcb *)); struct tcpcb * tcp_close __P((struct tcpcb *)); void tcp_ctlinput __P((int, struct sockaddr *, void *)); #if INET6 struct ip6_hdr; void tcp6_ctlinput __P((int, struct sockaddr *,void *)); #endif int tcp_ctloutput __P((struct socket *, struct sockopt *)); struct tcpcb * tcp_drop __P((struct tcpcb *, int)); void tcp_drain __P((void)); void tcp_fasttimo __P((void)); struct rmxp_tao * tcp_gettaocache __P((struct inpcb *)); void tcp_init __P((void)); #if INET6 void tcp6_init __P((void)); int tcp6_input __P((struct mbuf **, int *, int)); #endif /* INET6 */ void tcp_input __P((struct mbuf *, int)); #if INET6 void tcp_mss __P((struct tcpcb *, int, int)); int tcp_mssopt __P((struct tcpcb *, int)); #else /* INET6 */ void tcp_mss __P((struct tcpcb *, int)); int tcp_mssopt __P((struct tcpcb *)); #endif /* INET6 */ void tcp_mtudisc __P((struct inpcb *, int)); struct tcpcb * tcp_newtcpcb __P((struct inpcb *)); int tcp_output __P((struct tcpcb *)); void tcp_quench __P((struct inpcb *, int)); #if INET6 void tcp_respond __P((struct tcpcb *, void *, struct tcphdr *, struct mbuf *, tcp_seq, tcp_seq, int, int)); #else /* INET6 */ void tcp_respond __P((struct tcpcb *, void *, struct tcphdr *, struct mbuf *, tcp_seq, tcp_seq, int)); #endif /* INET6 */ struct rtentry * tcp_rtlookup __P((struct inpcb *)); #if INET6 struct rtentry * tcp_rtlookup6 __P((struct inpcb *)); #endif /* INET6 */ void tcp_setpersist __P((struct tcpcb *)); void tcp_slowtimo __P((void)); struct tcptemp * tcp_template __P((struct tcpcb *)); struct tcpcb * tcp_timers __P((struct tcpcb *, int)); #if INET6 void tcp_trace __P((int, int, struct tcpcb *, void *, struct tcphdr *, int)); #else void tcp_trace __P((int, int, struct tcpcb *, struct ip *, struct tcphdr *, int)); #endif #if INET6 int tcp_reass __P((struct tcpcb *, struct tcphdr *, int, struct mbuf *, int)); #else /* INET6 */ int tcp_reass __P((struct tcpcb *, struct tcphdr *, int, struct mbuf *)); /* suppress INET6 only args */ #define tcp_reass(x, y, z, t, i) tcp_reass(x, y, z, t) #define tcp_mss(x, y, i) tcp_mss(x, y) #define tcp_mssopt(x, i) tcp_mssopt(x) #define tcp_respond(x, y, z, m, s1, s2, f, i) tcp_respond(x, y, z, m, s1, \ s2, f) #endif /* INET6 */ extern struct pr_usrreqs tcp_usrreqs; #if INET6 extern struct pr_usrreqs tcp6_usrreqs; #endif /* INET6 */ extern u_long tcp_sendspace; extern u_long tcp_recvspace; #endif /* KERNEL */ #endif /* _NETINET_TCP_VAR_H_ */