1 /* 2 * Copyright (c) 1982, 1986 Regents of the University of California. 3 * All rights reserved. 4 * 5 * Redistribution and use in source and binary forms are permitted 6 * provided that this notice is preserved and that due credit is given 7 * to the University of California at Berkeley. The name of the University 8 * may not be used to endorse or promote products derived from this 9 * software without specific prior written permission. This software 10 * is provided ``as is'' without express or implied warranty. 11 * 12 * @(#)tcp_var.h 7.7 (Berkeley) 02/27/88 13 */ 14 15 /* 16 * TCP configuration: This is a half-assed attempt to make TCP 17 * self-configure for a few varieties of 4.2 and 4.3-based unixes. 18 * If you don't have a) a 4.3bsd vax or b) a 3.x Sun (x<6), check 19 * this carefully (it's probably not right). Please send me mail 20 * if you run into configuration problems. 21 * - Van Jacobson (van@lbl-csam.arpa) 22 */ 23 24 #ifndef BSD 25 #define BSD 42 /* if we're not 4.3, pretend we're 4.2 */ 26 #define OLDSTAT /* set if we have to use old netstat binaries */ 27 #endif 28 29 /* #define OLDSTAT /* set if we have to use old netstat binaries */ 30 31 #if sun || BSD < 43 32 #define TCP_COMPAT_42 /* set if we have to interop w/4.2 systems */ 33 #endif 34 35 #ifndef SB_MAX 36 #ifdef SB_MAXCOUNT 37 #define SB_MAX SB_MAXCOUNT /* Sun has to be a little bit different... */ 38 #else 39 #define SB_MAX 32767 /* XXX */ 40 #endif SB_MAXCOUNT 41 #endif SB_MAX 42 43 #ifndef IP_MAXPACKET 44 #define IP_MAXPACKET 65535 /* maximum packet size */ 45 #endif 46 47 /* 48 * Bill Nowicki pointed out that the page size (CLBYTES) has 49 * nothing to do with the mbuf cluster size. So, we followed 50 * Sun's lead and made the new define MCLBYTES stand for the mbuf 51 * cluster size. The following define makes up backwards compatible 52 * with 4.3 and 4.2. If CLBYTES is >1024 on your machine, check 53 * this against the mbuf cluster definitions in /usr/include/sys/mbuf.h. 54 */ 55 #ifndef MCLBYTES 56 #define MCLBYTES CLBYTES /* XXX */ 57 #endif 58 59 /* 60 * The routine in_localaddr is broken in Sun's 3.4. We redefine ours 61 * (in tcp_input.c) so we use can it but won't have a name conflict. 62 */ 63 #ifdef sun 64 #define in_localaddr tcp_in_localaddr 65 #endif 66 67 /* --------------- end of TCP config ---------------- */ 68 69 /* 70 * Kernel variables for tcp. 71 */ 72 73 /* 74 * Tcp control block, one per tcp; fields: 75 */ 76 struct tcpcb { 77 struct tcpiphdr *seg_next; /* sequencing queue */ 78 struct tcpiphdr *seg_prev; 79 short t_state; /* state of this connection */ 80 short t_timer[TCPT_NTIMERS]; /* tcp timers */ 81 short t_rxtshift; /* log(2) of rexmt exp. backoff */ 82 short t_rxtcur; /* current retransmit value */ 83 short t_dupacks; /* consecutive dup acks recd */ 84 u_short t_maxseg; /* maximum segment size */ 85 char t_force; /* 1 if forcing out a byte */ 86 u_char t_flags; 87 #define TF_ACKNOW 0x01 /* ack peer immediately */ 88 #define TF_DELACK 0x02 /* ack, but try to delay it */ 89 #define TF_NODELAY 0x04 /* don't delay packets to coalesce */ 90 #define TF_NOOPT 0x08 /* don't use tcp options */ 91 #define TF_SENTFIN 0x10 /* have sent FIN */ 92 struct tcpiphdr *t_template; /* skeletal packet for transmit */ 93 struct inpcb *t_inpcb; /* back pointer to internet pcb */ 94 /* 95 * The following fields are used as in the protocol specification. 96 * See RFC783, Dec. 1981, page 21. 97 */ 98 /* send sequence variables */ 99 tcp_seq snd_una; /* send unacknowledged */ 100 tcp_seq snd_nxt; /* send next */ 101 tcp_seq snd_up; /* send urgent pointer */ 102 tcp_seq snd_wl1; /* window update seg seq number */ 103 tcp_seq snd_wl2; /* window update seg ack number */ 104 tcp_seq iss; /* initial send sequence number */ 105 u_short snd_wnd; /* send window */ 106 /* receive sequence variables */ 107 u_short rcv_wnd; /* receive window */ 108 tcp_seq rcv_nxt; /* receive next */ 109 tcp_seq rcv_up; /* receive urgent pointer */ 110 tcp_seq irs; /* initial receive sequence number */ 111 /* 112 * Additional variables for this implementation. 113 */ 114 /* receive variables */ 115 tcp_seq rcv_adv; /* advertised window */ 116 /* retransmit variables */ 117 tcp_seq snd_max; /* highest sequence number sent 118 * used to recognize retransmits 119 */ 120 /* congestion control (for slow start, source quench, retransmit after loss) */ 121 u_short snd_cwnd; /* congestion-controlled window */ 122 u_short snd_ssthresh; /* snd_cwnd size threshhold for 123 * for slow start exponential to 124 * linear switch */ 125 /* 126 * transmit timing stuff. 127 * srtt and rttvar are stored as fixed point; for convenience in smoothing, 128 * srtt has 3 bits to the right of the binary point, rttvar has 2. 129 * "Variance" is actually smoothed difference. 130 */ 131 short t_idle; /* inactivity time */ 132 short t_rtt; /* round trip time */ 133 tcp_seq t_rtseq; /* sequence number being timed */ 134 short t_srtt; /* smoothed round-trip time */ 135 short t_rttvar; /* variance in round-trip time */ 136 u_short max_rcvd; /* most peer has sent into window */ 137 u_short max_sndwnd; /* largest window peer has offered */ 138 /* out-of-band data */ 139 char t_oobflags; /* have some */ 140 char t_iobc; /* input character */ 141 #define TCPOOB_HAVEDATA 0x01 142 #define TCPOOB_HADDATA 0x02 143 }; 144 145 #define intotcpcb(ip) ((struct tcpcb *)(ip)->inp_ppcb) 146 #define sototcpcb(so) (intotcpcb(sotoinpcb(so))) 147 148 /* 149 * TCP statistics. 150 * Many of these should be kept per connection, 151 * but that's inconvenient at the moment. 152 */ 153 struct tcpstat { 154 #ifdef OLDSTAT 155 /* 156 * Declare statistics the same as in 4.3 157 * at the start of tcpstat (same size and 158 * position) for netstat. 159 */ 160 int tcps_rcvbadsum; 161 int tcps_rcvbadoff; 162 int tcps_rcvshort; 163 int tcps_badsegs; 164 int tcps_unack; 165 #define tcps_badsum tcps_rcvbadsum 166 #define tcps_badoff tcps_rcvbadoff 167 #define tcps_hdrops tcps_rcvshort 168 169 #endif OLDSTAT 170 u_long tcps_connattempt; /* connections initiated */ 171 u_long tcps_accepts; /* connections accepted */ 172 u_long tcps_connects; /* connections established */ 173 u_long tcps_drops; /* connections dropped */ 174 u_long tcps_conndrops; /* embryonic connections dropped */ 175 u_long tcps_closed; /* conn. closed (includes drops) */ 176 u_long tcps_segstimed; /* segs where we tried to get rtt */ 177 u_long tcps_rttupdated; /* times we succeeded */ 178 u_long tcps_delack; /* delayed acks sent */ 179 u_long tcps_timeoutdrop; /* conn. dropped in rxmt timeout */ 180 u_long tcps_rexmttimeo; /* retransmit timeouts */ 181 u_long tcps_persisttimeo; /* persist timeouts */ 182 u_long tcps_keeptimeo; /* keepalive timeouts */ 183 u_long tcps_keepprobe; /* keepalive probes sent */ 184 u_long tcps_keepdrops; /* connections dropped in keepalive */ 185 186 u_long tcps_sndtotal; /* total packets sent */ 187 u_long tcps_sndpack; /* data packets sent */ 188 u_long tcps_sndbyte; /* data bytes sent */ 189 u_long tcps_sndrexmitpack; /* data packets retransmitted */ 190 u_long tcps_sndrexmitbyte; /* data bytes retransmitted */ 191 u_long tcps_sndacks; /* ack-only packets sent */ 192 u_long tcps_sndprobe; /* window probes sent */ 193 u_long tcps_sndurg; /* packets sent with URG only */ 194 u_long tcps_sndwinup; /* window update-only packets sent */ 195 u_long tcps_sndctrl; /* control (SYN|FIN|RST) packets sent */ 196 197 u_long tcps_rcvtotal; /* total packets received */ 198 u_long tcps_rcvpack; /* packets received in sequence */ 199 u_long tcps_rcvbyte; /* bytes received in sequence */ 200 #ifndef OLDSTAT 201 u_long tcps_rcvbadsum; /* packets received with ccksum errs */ 202 u_long tcps_rcvbadoff; /* packets received with bad offset */ 203 u_long tcps_rcvshort; /* packets received too short */ 204 #endif 205 u_long tcps_rcvduppack; /* duplicate-only packets received */ 206 u_long tcps_rcvdupbyte; /* duplicate-only bytes received */ 207 u_long tcps_rcvpartduppack; /* packets with some duplicate data */ 208 u_long tcps_rcvpartdupbyte; /* dup. bytes in part-dup. packets */ 209 u_long tcps_rcvoopack; /* out-of-order packets received */ 210 u_long tcps_rcvoobyte; /* out-of-order bytes received */ 211 u_long tcps_rcvpackafterwin; /* packets with data after window */ 212 u_long tcps_rcvbyteafterwin; /* bytes rcvd after window */ 213 u_long tcps_rcvafterclose; /* packets rcvd after "close" */ 214 u_long tcps_rcvwinprobe; /* rcvd window probe packets */ 215 u_long tcps_rcvdupack; /* rcvd duplicate acks */ 216 u_long tcps_rcvacktoomuch; /* rcvd acks for unsent data */ 217 u_long tcps_rcvackpack; /* rcvd ack packets */ 218 u_long tcps_rcvackbyte; /* bytes acked by rcvd acks */ 219 u_long tcps_rcvwinupd; /* rcvd window update packets */ 220 }; 221 222 #ifdef KERNEL 223 struct inpcb tcb; /* head of queue of active tcpcb's */ 224 struct tcpstat tcpstat; /* tcp statistics */ 225 struct tcpiphdr *tcp_template(); 226 struct tcpcb *tcp_close(), *tcp_drop(); 227 struct tcpcb *tcp_timers(), *tcp_disconnect(), *tcp_usrclosed(); 228 #endif 229