1*4682Swnj /* tcp_usrreq.c 1.20 81/10/30 */ 24567Swnj 34497Swnj #include "../h/param.h" 44567Swnj #include "../h/systm.h" 54664Swnj #include "../h/mbuf.h" 64664Swnj #include "../h/socket.h" 74664Swnj #include "../inet/inet.h" 84664Swnj #include "../inet/inet_systm.h" 94664Swnj #include "../inet/imp.h" 104664Swnj #include "../inet/ip.h" 114664Swnj #include "../inet/tcp.h" 124567Swnj #define TCPFSTAB 134584Swnj #ifdef TCPDEBUG 144584Swnj #define TCPSTATES 154584Swnj #endif 164664Swnj #include "../inet/tcp_fsm.h" 174497Swnj 184567Swnj tcp_timeo() 194497Swnj { 204567Swnj register struct tcb *tp; 214567Swnj int s = splnet(); 224567Swnj COUNT(TCP_TIMEO); 234497Swnj 244567Swnj /* 254567Swnj * Search through tcb's and update active timers. 264567Swnj */ 27*4682Swnj for (tp = tcb.tcb_next; tp != (struct tcb *)&tcb; tp = tp->tcb_next) { 284567Swnj if (tp->t_init != 0 && --tp->t_init == 0) 294567Swnj tcp_usrreq(ISTIMER, TINIT, tp, 0); 304567Swnj if (tp->t_rexmt != 0 && --tp->t_rexmt == 0) 314567Swnj tcp_usrreq(ISTIMER, TREXMT, tp, 0); 324567Swnj if (tp->t_rexmttl != 0 && --tp->t_rexmttl == 0) 334567Swnj tcp_usrreq(ISTIMER, TREXMTTL, tp, 0); 344567Swnj if (tp->t_persist != 0 && --tp->t_persist == 0) 354567Swnj tcp_usrreq(ISTIMER, TPERSIST, tp, 0); 364567Swnj if (tp->t_finack != 0 && --tp->t_finack == 0) 374567Swnj tcp_usrreq(ISTIMER, TFINACK, tp, 0); 384567Swnj tp->t_xmt++; 394567Swnj } 404664Swnj tcp_iss += ISSINCR; /* increment iss */ 414567Swnj timeout(tcp_timeo, 0, hz); /* reschedule every second */ 424567Swnj splx(s); 434497Swnj } 444497Swnj 454584Swnj tcp_usrreq(input, timertype, tp, mp) 464584Swnj int input, timertype; 474567Swnj register struct tcb *tp; 484584Swnj struct mbuf *mp; 494497Swnj { 504567Swnj int s = splnet(); 514567Swnj register int nstate; 524584Swnj #ifdef TCPDEBUG 534584Swnj struct tcp_debug tdb; 544584Swnj #endif 554567Swnj COUNT(TCP_USRREQ); 564497Swnj 574567Swnj nstate = tp->t_state; 584576Swnj tp->tc_flags &= ~TC_NET_KEEP; 594567Swnj acounts[nstate][input]++; 604584Swnj #ifdef TCPDEBUG 614584Swnj if ((tp->t_ucb->uc_flags & UDEBUG) || tcpconsdebug) { 624605Swnj tdb_setup(tp, (struct th *)0, input, &tdb); 634584Swnj tdb.td_tim = timertype; 644584Swnj } else 654584Swnj tdb.td_tod = 0; 664584Swnj #endif 674567Swnj switch (tcp_fstab[nstate][input]) { 684497Swnj 694567Swnj default: 704567Swnj printf("tcp: bad state: tcb=%x state=%d input=%d\n", 714567Swnj tp, tp->t_state, input); 724567Swnj nstate = EFAILEC; 734567Swnj break; 744497Swnj 754567Swnj case LIS_CLS: /* 1 */ 764676Swnj tcp_open(tp, PASSIVE); 774567Swnj nstate = LISTEN; 784567Swnj break; 794497Swnj 804567Swnj case SYS_CLS: /* 2 */ 814676Swnj tcp_open(tp, ACTIVE); 824676Swnj tcp_sndctl(tp); 834567Swnj nstate = SYN_SENT; 844567Swnj break; 854497Swnj 864567Swnj case CLS_OPN: /* 10 */ 874676Swnj tcp_close(tp, UCLOSED); 884567Swnj nstate = CLOSED; 894567Swnj break; 904497Swnj 914567Swnj case CL2_CLW: /* 10 */ 924576Swnj tp->tc_flags |= TC_SND_FIN; 934676Swnj tcp_sndctl(tp); 944576Swnj tp->tc_flags |= TC_USR_CLOSED; 954567Swnj nstate = CLOSING2; 964567Swnj break; 974497Swnj 984567Swnj case TIMERS: /* 14,17,34,35,36,37,38 */ 994584Swnj nstate = tcp_timers(tp, timertype); 1004567Swnj break; 1014497Swnj 1024567Swnj case CLS_RWT: /* 20 */ 1034567Swnj present_data(tp); 1044567Swnj if (rcv_empty(tp)) { 1054676Swnj tcp_close(tp, UCLOSED); 1064567Swnj nstate = CLOSED; 1074567Swnj } else 1084567Swnj nstate = RCV_WAIT; 1094567Swnj break; 1104497Swnj 1114567Swnj case FW1_SYR: /* 24,25 */ 1124576Swnj tp->tc_flags |= TC_SND_FIN; 1134676Swnj tcp_sndctl(tp); 1144576Swnj tp->tc_flags |= TC_USR_CLOSED; 1154567Swnj nstate = FIN_W1; 1164567Swnj break; 1174567Swnj 1184567Swnj case SSS_SND: /* 40,41 */ 1194678Swnj nstate = tcp_usrsend(tp, mp); 1204567Swnj break; 1214567Swnj 1224567Swnj case SSS_RCV: /* 42 */ 1234676Swnj tcp_sndwin(tp); /* send new window */ 1244567Swnj present_data(tp); 1254567Swnj break; 1264567Swnj 1274567Swnj case CLS_NSY: /* 44 */ 1284676Swnj tcp_close(tp, UABORT); 1294567Swnj nstate = CLOSED; 1304567Swnj break; 1314567Swnj 1324567Swnj case CLS_SYN: /* 45 */ 1334576Swnj tp->tc_flags |= TC_SND_RST; 1344676Swnj tcp_sndnull(tp); 1354676Swnj tcp_close(tp, UABORT); 1364567Swnj nstate = CLOSED; 1374567Swnj break; 1384567Swnj 1394567Swnj case CLS_ACT: /* 47 */ 1404676Swnj tcp_close(tp, UNETDWN); 1414567Swnj nstate = CLOSED; 1424567Swnj break; 1434567Swnj 1444567Swnj case NOP: 1454567Swnj break; 1464567Swnj 1474567Swnj case CLS_ERR: 1484567Swnj to_user(tp->t_ucb, UCLSERR); 1494567Swnj break; 1504567Swnj } 1514567Swnj #ifdef TCPDEBUG 1524605Swnj if (tdb.td_tod) 1534605Swnj tdb_stuff(&tdb, nstate); 1544567Swnj #endif 1554567Swnj /* YECH */ 1564567Swnj switch (nstate) { 1574567Swnj 1584584Swnj case CLOSED: 1594567Swnj case SAME: 1604567Swnj break; 1614567Swnj 1624567Swnj case EFAILEC: 1634584Swnj if (mp) 1644584Swnj m_freem(dtom(mp)); 1654567Swnj break; 1664567Swnj 1674567Swnj default: 1684567Swnj tp->t_state = nstate; 1694567Swnj break; 1704567Swnj } 1714567Swnj splx(s); 1724497Swnj } 1734497Swnj 174*4682Swnj /* 175*4682Swnj * Open routine, called to initialize newly created tcb fields. 176*4682Swnj */ 177*4682Swnj tcp_open(tp, mode) 1784567Swnj register struct tcb *tp; 1794567Swnj int mode; 1804497Swnj { 181*4682Swnj register struct ucb *up = tp->t_ucb; 182*4682Swnj COUNT(TCP_OPEN); 1834497Swnj 184*4682Swnj /* 185*4682Swnj * Link in tcb queue and make 186*4682Swnj * initialize empty reassembly queue. 187*4682Swnj */ 188*4682Swnj tp->tcb_next = tcb.tcb_next; 189*4682Swnj tcb.tcb_next->tcb_prev = tp; 190*4682Swnj tp->tcb_prev = (struct tcb *)&tcb; 191*4682Swnj tcb.tcb_next = tp; 192*4682Swnj tp->t_rcv_next = tp->t_rcv_prev = (struct th *)tp; 1934497Swnj 194*4682Swnj /* 195*4682Swnj * Initialize sequence numbers and 196*4682Swnj * round trip retransmit timer. 197*4682Swnj * (Other fields were init'd to zero when tcb allocated.) 198*4682Swnj */ 1994567Swnj tp->t_xmtime = T_REXMT; 200*4682Swnj tp->snd_end = tp->seq_fin = tp->snd_nxt = tp->snd_hi = tp->snd_una = 201*4682Swnj tp->iss = tcp_iss; 2024567Swnj tp->snd_off = tp->iss + 1; 2034664Swnj tcp_iss += (ISSINCR >> 1) + 1; 2044567Swnj 205*4682Swnj /* 206*4682Swnj * Set timeout for open. 207*4682Swnj * SHOULD THIS BE A HIGHER LEVEL FUNCTION!?! THINK SO. 208*4682Swnj */ 209*4682Swnj if (up->uc_timeo) 210*4682Swnj tp->t_init = up->uc_timeo; 211*4682Swnj else if (mode == ACTIVE) 212*4682Swnj tp->t_init = T_INIT; 213*4682Swnj /* else 214*4682Swnj tp->t_init = 0; */ 215*4682Swnj up->uc_timeo = 0; /* ### */ 2164497Swnj } 2174497Swnj 218*4682Swnj /* 219*4682Swnj * Internal close of a connection, shutting down the tcb. 220*4682Swnj */ 2214676Swnj tcp_close(tp, state) 2224567Swnj register struct tcb *tp; 2234567Swnj short state; 2244497Swnj { 225*4682Swnj register struct ucb *up = tp->t_ucb; 2264567Swnj register struct th *t; 2274567Swnj register struct mbuf *m; 228*4682Swnj COUNT(TCP_CLOSE); 2294497Swnj 230*4682Swnj /* 231*4682Swnj * Cancel all timers. 232*4682Swnj * SHOULD LOOP HERE !?! 233*4682Swnj */ 2344567Swnj tp->t_init = tp->t_rexmt = tp->t_rexmttl = tp->t_persist = 2354567Swnj tp->t_finack = 0; 2364497Swnj 237*4682Swnj /* 238*4682Swnj * Remque the tcb 239*4682Swnj */ 240*4682Swnj tp->tcb_prev->tcb_next = tp->tcb_next; 241*4682Swnj tp->tcb_next->tcb_prev = tp->tcb_prev; 2424567Swnj 243*4682Swnj /* 244*4682Swnj * Discard all buffers... 245*4682Swnj * 246*4682Swnj * SHOULD COUNT EACH RESOURCE TO 0 AND PANIC IF CONFUSED 247*4682Swnj */ 2484567Swnj for (t = tp->t_rcv_next; t != (struct th *)tp; t = t->t_next) 2494567Swnj m_freem(dtom(t)); 2504567Swnj if (up->uc_rbuf != NULL) { 2514567Swnj m_freem(up->uc_rbuf); 2524567Swnj up->uc_rbuf = NULL; 2534567Swnj } 2544657Swnj up->uc_rcc = 0; 2554567Swnj if (up->uc_sbuf != NULL) { 2564567Swnj m_freem(up->uc_sbuf); 2574567Swnj up->uc_sbuf = NULL; 2584567Swnj } 2594592Swnj up->uc_ssize = 0; 2604567Swnj for (m = tp->t_rcv_unack; m != NULL; m = m->m_act) { 2614567Swnj m_freem(m); 2624567Swnj tp->t_rcv_unack = NULL; 2634567Swnj } 264*4682Swnj 265*4682Swnj /* 266*4682Swnj * Free tcp send template. 267*4682Swnj */ 2684664Swnj if (up->uc_template) { 2694664Swnj m_free(dtom(up->uc_template)); 2704664Swnj up->uc_template = 0; 2714664Swnj } 272*4682Swnj 273*4682Swnj /* 274*4682Swnj * Free the tcb 275*4682Swnj * WOULD THIS BETTER BE DONE AT USER CLOSE? 276*4682Swnj */ 2774670Swnj wmemfree((caddr_t)tp, 1024); 2784567Swnj up->uc_tcb = NULL; 2794567Swnj 280*4682Swnj /* 281*4682Swnj * Lower buffer allocation. 282*4682Swnj * SHOULD BE A M_ROUTINE CALL. 283*4682Swnj */ 2844664Swnj mbstat.m_lowat -= up->uc_snd + (up->uc_rhiwat/MSIZE) + 2; 2854664Swnj mbstat.m_hiwat = 2 * mbstat.m_lowat; 286*4682Swnj 287*4682Swnj /* 288*4682Swnj * Free routing table entry. 289*4682Swnj */ 2904567Swnj if (up->uc_host != NULL) { 2914567Swnj h_free(up->uc_host); 2924567Swnj up->uc_host = NULL; 2934567Swnj } 2944567Swnj 295*4682Swnj /* 296*4682Swnj * If user has initiated close (via close call), delete ucb 297*4682Swnj * entry, otherwise just wakeup so user can issue close call 298*4682Swnj */ 2994576Swnj if (tp->tc_flags&TC_USR_ABORT) 3004567Swnj up->uc_proc = NULL; 3014567Swnj else 302*4682Swnj to_user(up, state); /* ### */ 3034497Swnj } 3044497Swnj 305*4682Swnj /* 306*4682Swnj * User routine to send data queue headed by m0 into the protocol. 307*4682Swnj */ 3084678Swnj tcp_usrsend(tp, m0) 3094584Swnj register struct tcb *tp; 3104584Swnj struct mbuf *m0; 3114497Swnj { 3124497Swnj register struct mbuf *m, *n; 3134584Swnj register struct ucb *up = tp->t_ucb; 3144497Swnj register off; 3154574Swnj seq_t last; 316*4682Swnj COUNT(TCP_USRSEND); 3174497Swnj 3184497Swnj last = tp->snd_off; 3194584Swnj for (m = n = m0; m != NULL; m = m->m_next) { 3204497Swnj up->uc_ssize++; 3214591Swnj if (m->m_off > MMAXOFF) 3224588Swnj up->uc_ssize += NMBPG; 3234497Swnj last += m->m_len; 3244497Swnj } 3254588Swnj if ((m = up->uc_sbuf) == NULL) 3264588Swnj up->uc_sbuf = n; 3274588Swnj else { 3284588Swnj while (m->m_next != NULL) { 3294497Swnj m = m->m_next; 3304497Swnj last += m->m_len; 3314497Swnj } 3324591Swnj if (m->m_off <= MMAXOFF) { 3334588Swnj last += m->m_len; 3344588Swnj off = m->m_off + m->m_len; 3354591Swnj while (n && n->m_off <= MMAXOFF && 3364591Swnj (MMAXOFF - off) >= n->m_len) { 3374588Swnj bcopy((caddr_t)((int)n + n->m_off), 3384588Swnj (caddr_t)((int)m + off), n->m_len); 3394588Swnj m->m_len += n->m_len; 3404588Swnj off += n->m_len; 3414588Swnj up->uc_ssize--; 3424588Swnj n = m_free(n); 3434588Swnj } 3444497Swnj } 3454497Swnj m->m_next = n; 3464588Swnj } 3474588Swnj if (up->uc_flags & UEOL) 3484497Swnj tp->snd_end = last; 3494588Swnj if (up->uc_flags & UURG) { 3504497Swnj tp->snd_urp = last+1; 3514576Swnj tp->tc_flags |= TC_SND_URG; 3524567Swnj } 3534678Swnj tcp_send(tp); 3544567Swnj return (SAME); 3554497Swnj } 3564497Swnj 357*4682Swnj /* 358*4682Swnj * TCP timer went off processing. 359*4682Swnj */ 3604584Swnj tcp_timers(tp, timertype) 3614584Swnj register struct tcb *tp; 3624584Swnj int timertype; 3634497Swnj { 3644497Swnj 3654567Swnj COUNT(TCP_TIMERS); 3664584Swnj switch (timertype) { 3674497Swnj 3684567Swnj case TINIT: /* initialization timer */ 3694576Swnj if ((tp->tc_flags&TC_SYN_ACKED) == 0) { /* 35 */ 3704676Swnj tcp_close(tp, UINTIMO); 3714567Swnj return (CLOSED); 3724567Swnj } 3734567Swnj return (SAME); 3744497Swnj 3754567Swnj case TFINACK: /* fin-ack timer */ 3764567Swnj switch (tp->t_state) { 3774497Swnj 3784567Swnj case TIME_WAIT: 3794567Swnj /* 3804567Swnj * We can be sure our ACK of foreign FIN was rcvd, 3814567Swnj * and can close if no data left for user. 3824567Swnj */ 3834567Swnj if (rcv_empty(tp)) { 3844676Swnj tcp_close(tp, UCLOSED); /* 14 */ 3854567Swnj return (CLOSED); 3864567Swnj } 3874567Swnj return (RCV_WAIT); /* 17 */ 3884497Swnj 3894567Swnj case CLOSING1: 3904576Swnj tp->tc_flags |= TC_WAITED_2_ML; 3914567Swnj return (SAME); 3924497Swnj 3934567Swnj default: 3944567Swnj return (SAME); 3954567Swnj } 3964497Swnj 3974567Swnj case TREXMT: /* retransmission timer */ 3984567Swnj if (tp->t_rexmt_val > tp->snd_una) { /* 34 */ 3994567Swnj /* 4004567Swnj * Set up for a retransmission, increase rexmt time 4014567Swnj * in case of multiple retransmissions. 4024567Swnj */ 4034567Swnj tp->snd_nxt = tp->snd_una; 4044576Swnj tp->tc_flags |= TC_REXMT; 4054567Swnj tp->t_xmtime = tp->t_xmtime << 1; 4064567Swnj if (tp->t_xmtime > T_REMAX) 4074567Swnj tp->t_xmtime = T_REMAX; 4084678Swnj tcp_send(tp); 4094567Swnj } 4104567Swnj return (SAME); 4114497Swnj 4124567Swnj case TREXMTTL: /* retransmit too long */ 4134567Swnj if (tp->t_rtl_val > tp->snd_una) /* 36 */ 4144567Swnj to_user(tp->t_ucb, URXTIMO); 4154567Swnj /* 4164567Swnj * If user has already closed, abort the connection. 4174567Swnj */ 4184576Swnj if (tp->tc_flags & TC_USR_CLOSED) { 4194676Swnj tcp_close(tp, URXTIMO); 4204567Swnj return (CLOSED); 4214567Swnj } 4224567Swnj return (SAME); 4234497Swnj 4244567Swnj case TPERSIST: /* persist timer */ 4254567Swnj /* 4264567Swnj * Force a byte send through closed window. 4274567Swnj */ 4284576Swnj tp->tc_flags |= TC_FORCE_ONE; 4294678Swnj tcp_send(tp); 4304567Swnj return (SAME); 4314567Swnj } 4324567Swnj panic("tcp_timers"); 4334497Swnj } 4344497Swnj 4354567Swnj /* THIS ROUTINE IS A CROCK */ 4364567Swnj to_user(up, state) 4374567Swnj register struct ucb *up; 4384567Swnj register short state; 4394497Swnj { 4404567Swnj COUNT(TO_USER); 4414497Swnj 4424567Swnj up->uc_state |= state; 4434567Swnj netwakeup(up); 4444567Swnj if (state == UURGENT) 4454567Swnj psignal(up->uc_proc, SIGURG); 4464497Swnj } 4474584Swnj 4484584Swnj #ifdef TCPDEBUG 449*4682Swnj /* 450*4682Swnj * TCP debugging utility subroutines. 451*4682Swnj * THE NAMES OF THE FIELDS USED BY THESE ROUTINES ARE STUPID. 452*4682Swnj */ 4534670Swnj tdb_setup(tp, n, input, tdp) 4544670Swnj struct tcb *tp; 4554670Swnj register struct th *n; 4564670Swnj int input; 4574670Swnj register struct tcp_debug *tdp; 4584670Swnj { 4594670Swnj 460*4682Swnj COUNT(TDB_SETUP); 4614670Swnj tdp->td_tod = time; 4624670Swnj tdp->td_tcb = tp; 4634670Swnj tdp->td_old = tp->t_state; 4644670Swnj tdp->td_inp = input; 4654670Swnj tdp->td_tim = 0; 4664670Swnj tdp->td_new = -1; 4674670Swnj if (n) { 4684670Swnj tdp->td_sno = n->t_seq; 4694670Swnj tdp->td_ano = n->t_ackno; 4704670Swnj tdp->td_wno = n->t_win; 4714670Swnj tdp->td_lno = n->t_len; 4724670Swnj tdp->td_flg = n->th_flags; 4734670Swnj } else 4744670Swnj tdp->td_sno = tdp->td_ano = tdp->td_wno = tdp->td_lno = 4754670Swnj tdp->td_flg = 0; 4764670Swnj } 4774670Swnj 4784670Swnj tdb_stuff(tdp, nstate) 4794670Swnj struct tcp_debug *tdp; 4804670Swnj int nstate; 4814670Swnj { 482*4682Swnj COUNT(TDB_STUFF); 4834670Swnj 4844670Swnj tdp->td_new = nstate; 4854670Swnj tcp_debug[tdbx++ % TDBSIZE] = *tdp; 4864670Swnj if (tcpconsdebug & 2) 4874670Swnj tcp_prt(tdp); 4884670Swnj } 489*4682Swnj 490*4682Swnj /* BETTER VERSION OF THIS ROUTINE? */ 491*4682Swnj tcp_prt(tdp) 492*4682Swnj register struct tcp_debug *tdp; 493*4682Swnj { 494*4682Swnj COUNT(TCP_PRT); 495*4682Swnj 496*4682Swnj printf("TCP(%x) %s x %s", 497*4682Swnj tdp->td_tcb, tcpstates[tdp->td_old], tcpinputs[tdp->td_inp]); 498*4682Swnj if (tdp->td_inp == ISTIMER) 499*4682Swnj printf("(%s)", tcptimers[tdp->td_tim]); 500*4682Swnj printf(" --> %s", 501*4682Swnj tcpstates[(tdp->td_new > 0) ? tdp->td_new : tdp->td_old]); 502*4682Swnj /* GROSS... DEPENDS ON SIGN EXTENSION OF CHARACTERS */ 503*4682Swnj if (tdp->td_new < 0) 504*4682Swnj printf(" (FAILED)"); 505*4682Swnj if (tdp->td_sno) { 506*4682Swnj printf(" sno %x ano %x win %d len %d flags %x", 507*4682Swnj tdp->td_sno, tdp->td_ano, tdp->td_wno, 508*4682Swnj tdp->td_lno, tdp->td_flg); 509*4682Swnj } 510*4682Swnj printf("\n"); 511*4682Swnj } 5124670Swnj #endif 513