ref: 909323e92a4e694bff5908e500d8655ac1bbd932
dir: /sys/src/9/ip/il.c/
#include "u.h" #include "../port/lib.h" #include "mem.h" #include "dat.h" #include "fns.h" #include "../port/error.h" #include "ip.h" enum /* Connection state */ { Ilclosed, Ilsyncer, Ilsyncee, Ilestablished, Illistening, Ilclosing, Ilopening, /* only for file server */ }; char *ilstates[] = { "Closed", "Syncer", "Syncee", "Established", "Listen", "Closing", "Opening", /* only for file server */ }; enum /* Packet types */ { Ilsync, Ildata, Ildataquery, Ilack, Ilquery, Ilstate, Ilclose, }; char *iltype[] = { "sync", "data", "dataquery", "ack", "query", "state", "close" }; enum { Seconds = 1000, Iltickms = 50, /* time base */ AckDelay = 2*Iltickms, /* max time twixt message rcvd & ack sent */ MaxTimeout = 30*Seconds, /* max time between rexmit */ QueryTime = 10*Seconds, /* time between subsequent queries */ DeathTime = 30*QueryTime, MaxRexmit = 16, /* max retransmissions before hangup */ Defaultwin = 20, LogAGain = 3, AGain = 1<<LogAGain, LogDGain = 2, DGain = 1<<LogDGain, DefByteRate = 100, /* assume a megabit link */ DefRtt = 50, /* cross country on a great day */ Maxrq = 64*1024, }; enum { Nqt= 8, }; typedef struct Ilcb Ilcb; struct Ilcb /* Control block */ { int state; /* Connection state */ Conv *conv; QLock ackq; /* Unacknowledged queue */ Block *unacked; Block *unackedtail; ulong unackedbytes; QLock outo; /* Out of order packet queue */ Block *outoforder; ulong next; /* Id of next to send */ ulong recvd; /* Last packet received */ ulong acksent; /* Last packet acked */ ulong start; /* Local start id */ ulong rstart; /* Remote start id */ int window; /* Maximum receive window */ int rxquery; /* number of queries on this connection */ int rxtot; /* number of retransmits on this connection */ int rexmit; /* number of retransmits of *unacked */ ulong qt[Nqt+1]; /* state table for query messages */ int qtx; /* ... index into qt */ /* if set, fasttimeout causes a connection request to terminate after 4*Iltickms */ int fasttimeout; /* timers */ ulong lastxmit; /* time of last xmit */ ulong lastrecv; /* time of last recv */ ulong timeout; /* retransmission time for *unacked */ ulong acktime; /* time to send next ack */ ulong querytime; /* time to send next query */ /* adaptive measurements */ int delay; /* Average of the fixed rtt delay */ int rate; /* Average uchar rate */ int mdev; /* Mean deviation of rtt */ int maxrtt; /* largest rtt seen */ ulong rttack; /* The ack we are waiting for */ int rttlen; /* Length of rttack packet */ uvlong rttstart; /* Time we issued rttack packet */ }; enum { IL_IPSIZE = 20, IL_HDRSIZE = 18, IL_LISTEN = 0, IL_CONNECT = 1, IP_ILPROTO = 40, }; typedef struct Ilhdr Ilhdr; struct Ilhdr { uchar vihl; /* Version and header length */ uchar tos; /* Type of service */ uchar length[2]; /* packet length */ uchar id[2]; /* Identification */ uchar frag[2]; /* Fragment information */ uchar ttl; /* Time to live */ uchar proto; /* Protocol */ uchar cksum[2]; /* Header checksum */ uchar src[4]; /* Ip source */ uchar dst[4]; /* Ip destination */ uchar ilsum[2]; /* Checksum including header */ uchar illen[2]; /* Packet length */ uchar iltype; /* Packet type */ uchar ilspec; /* Special */ uchar ilsrc[2]; /* Src port */ uchar ildst[2]; /* Dst port */ uchar ilid[4]; /* Sequence id */ uchar ilack[4]; /* Acked sequence */ }; enum { InMsgs, OutMsgs, CsumErrs, /* checksum errors */ HlenErrs, /* header length error */ LenErrs, /* short packet */ OutOfOrder, /* out of order */ Retrans, /* retransmissions */ DupMsg, DupBytes, DroppedMsgs, Nstats, }; static char *statnames[] = { [InMsgs] "InMsgs", [OutMsgs] "OutMsgs", [CsumErrs] "CsumErrs", [HlenErrs] "HlenErr", [LenErrs] "LenErrs", [OutOfOrder] "OutOfOrder", [Retrans] "Retrans", [DupMsg] "DupMsg", [DupBytes] "DupBytes", [DroppedMsgs] "DroppedMsgs", }; typedef struct Ilpriv Ilpriv; struct Ilpriv { Ipht ht; uvlong stats[Nstats]; ulong csumerr; /* checksum errors */ ulong hlenerr; /* header length error */ ulong lenerr; /* short packet */ ulong order; /* out of order */ ulong rexmit; /* retransmissions */ ulong dup; ulong dupb; /* keeping track of the ack kproc */ int ackprocstarted; QLock apl; }; /* state for query/dataquery messages */ void ilrcvmsg(Conv*, Block*); int ilsendctl(Conv*, Ilhdr*, int, ulong, ulong, int); void ilackq(Ilcb*, Block*); void ilprocess(Conv*, Ilhdr*, Block*); void ilpullup(Conv*); void ilhangup(Conv*, char*); void ilfreeq(Ilcb*); void ilrexmit(Ilcb*); void ilbackoff(Ilcb*); void ilsettimeout(Ilcb*); char* ilstart(Conv*, int, int); void ilackproc(void*); void iloutoforder(Conv*, Ilhdr*, Block*); void iliput(Proto*, Ipifc*, Block*); void iladvise(Proto*, Block*, char*); int ilnextqt(Ilcb*); void ilcbinit(Ilcb*); int later(ulong, ulong, char*); void ilreject(Fs*, Ilhdr*); void illocalclose(Conv *c); int ilcksum = 1; static int initseq = 25001; static ulong scalediv, scalemul; static char *etime = "connection timed out"; static char* ilconnect(Conv *c, char **argv, int argc) { char *e, *p; int fast; /* huge hack to quickly try an il connection */ fast = 0; if(argc > 1){ p = strstr(argv[1], "!fasttimeout"); if(p != nil){ *p = 0; fast = 1; } } e = Fsstdconnect(c, argv, argc); if(e != nil) return e; if(c->ipversion != V4) return "only IP version 4 supported"; return ilstart(c, IL_CONNECT, fast); } static int ilstate(Conv *c, char *state, int n) { Ilcb *ic; ic = (Ilcb*)(c->ptcl); return snprint(state, n, "%s qin %d qout %d del %5.5d Br %5.5d md %5.5d una %5.5lud rex %5.5d rxq %5.5d max %5.5d\n", ilstates[ic->state], c->rq ? qlen(c->rq) : 0, c->wq ? qlen(c->wq) : 0, ic->delay>>LogAGain, ic->rate>>LogAGain, ic->mdev>>LogDGain, ic->unackedbytes, ic->rxtot, ic->rxquery, ic->maxrtt); } static int ilinuse(Conv *c) { Ilcb *ic; ic = (Ilcb*)(c->ptcl); return ic->state != Ilclosed; } /* called with c locked */ static char* ilannounce(Conv *c, char **argv, int argc) { char *e; e = Fsstdannounce(c, argv, argc); if(e != nil) return e; e = ilstart(c, IL_LISTEN, 0); if(e != nil) return e; Fsconnected(c, nil); return nil; } void illocalclose(Conv *c) { Ilcb *ic; Ilpriv *ipriv; ipriv = c->p->priv; ic = (Ilcb*)c->ptcl; ic->state = Ilclosed; iphtrem(&ipriv->ht, c); c->lport = 0; ipmove(c->laddr, IPnoaddr); } static void ilclose(Conv *c) { Ilcb *ic; ic = (Ilcb*)c->ptcl; qclose(c->rq); qclose(c->wq); qclose(c->eq); switch(ic->state) { case Ilclosing: case Ilclosed: break; case Ilsyncer: case Ilsyncee: case Ilestablished: ic->state = Ilclosing; ilsettimeout(ic); ilsendctl(c, nil, Ilclose, ic->next, ic->recvd, 0); break; case Illistening: illocalclose(c); break; } ilfreeq(ic); } void ilkick(void *x, Block *bp) { Conv *c = x; Ilhdr *ih; Ilcb *ic; int dlen; ulong id, ack; Fs *f; Ilpriv *priv; f = c->p->f; priv = c->p->priv; ic = (Ilcb*)c->ptcl; if(bp == nil) return; switch(ic->state) { case Ilclosed: case Illistening: case Ilclosing: freeblist(bp); qhangup(c->rq, nil); return; } dlen = blocklen(bp); /* Make space to fit il & ip */ bp = padblock(bp, IL_IPSIZE+IL_HDRSIZE); ih = (Ilhdr *)(bp->rp); ih->vihl = IP_VER4; /* Ip fields */ ih->frag[0] = 0; ih->frag[1] = 0; v6tov4(ih->dst, c->raddr); v6tov4(ih->src, c->laddr); ih->proto = IP_ILPROTO; /* Il fields */ hnputs(ih->illen, dlen+IL_HDRSIZE); hnputs(ih->ilsrc, c->lport); hnputs(ih->ildst, c->rport); qlock(&ic->ackq); id = ic->next++; hnputl(ih->ilid, id); ack = ic->recvd; hnputl(ih->ilack, ack); ic->acksent = ack; ic->acktime = NOW + AckDelay; ih->iltype = Ildata; ih->ilspec = 0; ih->ilsum[0] = 0; ih->ilsum[1] = 0; /* Checksum of ilheader plus data (not ip & no pseudo header) */ if(ilcksum) hnputs(ih->ilsum, ptclcsum(bp, IL_IPSIZE, dlen+IL_HDRSIZE)); ilackq(ic, bp); qunlock(&ic->ackq); /* Start the round trip timer for this packet if the timer is free */ if(ic->rttack == 0) { ic->rttack = id; ic->rttstart = fastticks(nil); ic->rttlen = dlen + IL_IPSIZE + IL_HDRSIZE; } if(later(NOW, ic->timeout, nil)) ilsettimeout(ic); ipoput4(f, bp, 0, c->ttl, c->tos, c); priv->stats[OutMsgs]++; } static void ilcreate(Conv *c) { c->rq = qopen(Maxrq, 0, 0, c); c->wq = qbypass(ilkick, c); } int ilxstats(Proto *il, char *buf, int len) { Ilpriv *priv; char *p, *e; int i; priv = il->priv; p = buf; e = p+len; for(i = 0; i < Nstats; i++) p = seprint(p, e, "%s: %llud\n", statnames[i], priv->stats[i]); return p - buf; } void ilackq(Ilcb *ic, Block *bp) { Block *np; int n; n = blocklen(bp); /* Enqueue a copy on the unacked queue in case this one gets lost */ np = copyblock(bp, n); if(ic->unacked) ic->unackedtail->list = np; else ic->unacked = np; ic->unackedtail = np; np->list = nil; ic->unackedbytes += n; } static void ilrttcalc(Ilcb *ic, Block *bp) { int rtt, tt, pt, delay, rate; rtt = fastticks(nil) - ic->rttstart; rtt = (rtt*scalemul)/scalediv; delay = ic->delay; rate = ic->rate; /* Guard against zero wrap */ if(rtt > 120000 || rtt < 0) return; /* this block had to be transmitted after the one acked so count its size */ ic->rttlen += blocklen(bp) + IL_IPSIZE + IL_HDRSIZE; if(ic->rttlen < 256){ /* guess fixed delay as rtt of small packets */ delay += rtt - (delay>>LogAGain); if(delay < AGain) delay = AGain; ic->delay = delay; } else { /* if packet took longer than avg rtt delay, recalc rate */ tt = rtt - (delay>>LogAGain); if(tt > 0){ rate += ic->rttlen/tt - (rate>>LogAGain); if(rate < AGain) rate = AGain; ic->rate = rate; } } /* mdev */ pt = ic->rttlen/(rate>>LogAGain) + (delay>>LogAGain); ic->mdev += abs(rtt-pt) - (ic->mdev>>LogDGain); if(rtt > ic->maxrtt) ic->maxrtt = rtt; } void ilackto(Ilcb *ic, ulong ackto, Block *bp) { Ilhdr *h; ulong id; if(ic->rttack == ackto) ilrttcalc(ic, bp); /* Cancel if we've passed the packet we were interested in */ if(ic->rttack <= ackto) ic->rttack = 0; qlock(&ic->ackq); while(ic->unacked) { h = (Ilhdr *)ic->unacked->rp; id = nhgetl(h->ilid); if(ackto < id) break; bp = ic->unacked; ic->unacked = bp->list; bp->list = nil; ic->unackedbytes -= blocklen(bp); freeblist(bp); ic->rexmit = 0; ilsettimeout(ic); } qunlock(&ic->ackq); } void iliput(Proto *il, Ipifc*, Block *bp) { char *st; Ilcb *ic; Ilhdr *ih; uchar raddr[IPaddrlen]; uchar laddr[IPaddrlen]; ushort sp, dp, csum; int plen, illen; Iphash *iph; Conv *new, *s; Ilpriv *ipriv; ipriv = il->priv; ih = (Ilhdr *)bp->rp; plen = blocklen(bp); if(plen > 0 && (ih->vihl&0xF0)!=IP_VER4) goto raise; /* ignore non V4 packets */ if(plen < IL_IPSIZE+IL_HDRSIZE){ netlog(il->f, Logil, "il: hlenerr\n"); ipriv->stats[HlenErrs]++; goto raise; } illen = nhgets(ih->illen); if(illen+IL_IPSIZE > plen){ netlog(il->f, Logil, "il: lenerr\n"); ipriv->stats[LenErrs]++; goto raise; } sp = nhgets(ih->ildst); dp = nhgets(ih->ilsrc); v4tov6(raddr, ih->src); v4tov6(laddr, ih->dst); if((csum = ptclcsum(bp, IL_IPSIZE, illen)) != 0) { if(ih->iltype > Ilclose) st = "?"; else st = iltype[ih->iltype]; ipriv->stats[CsumErrs]++; netlog(il->f, Logil, "il: cksum %ux %s, pkt(%ux id %ud ack %I/%d->%d)\n", csum, st, nhgetl(ih->ilid), nhgetl(ih->ilack), raddr, sp, dp); goto raise; } qlock(il); iph = iphtlook(&ipriv->ht, raddr, dp, laddr, sp); if(iph == nil){ if(ih->iltype == Ilsync) ilreject(il->f, ih); /* no listener */ qunlock(il); goto raise; } s = iphconv(iph); ic = (Ilcb*)s->ptcl; if(ic->state == Illistening){ if(ih->iltype != Ilsync){ qunlock(il); if(ih->iltype > Ilclose) st = "?"; else st = iltype[ih->iltype]; ilreject(il->f, ih); /* no channel and not sync */ netlog(il->f, Logil, "il: no channel, pkt(%s id %ud ack %ud %I/%ud->%ud)\n", st, nhgetl(ih->ilid), nhgetl(ih->ilack), raddr, sp, dp); goto raise; } new = Fsnewcall(s, raddr, dp, laddr, sp, V4); if(new == nil){ qunlock(il); netlog(il->f, Logil, "il: bad newcall %I/%ud->%ud\n", raddr, sp, dp); ilsendctl(s, ih, Ilclose, 0, nhgetl(ih->ilid), 0); goto raise; } s = new; ic = (Ilcb*)s->ptcl; ic->conv = s; ic->state = Ilsyncee; ilcbinit(ic); ic->rstart = nhgetl(ih->ilid); iphtadd(&ipriv->ht, s); } qlock(s); qunlock(il); if(waserror()){ qunlock(s); nexterror(); } ilprocess(s, ih, bp); qunlock(s); poperror(); return; raise: freeblist(bp); } void _ilprocess(Conv *s, Ilhdr *h, Block *bp) { Ilcb *ic; ulong id, ack; Ilpriv *priv; id = nhgetl(h->ilid); ack = nhgetl(h->ilack); ic = (Ilcb*)s->ptcl; ic->lastrecv = NOW; ic->querytime = NOW + QueryTime; priv = s->p->priv; priv->stats[InMsgs]++; switch(ic->state) { default: netlog(s->p->f, Logil, "il: unknown state %d\n", ic->state); case Ilclosed: freeblist(bp); break; case Ilsyncer: switch(h->iltype) { default: break; case Ilsync: if(ack != ic->start) ilhangup(s, "connection rejected"); else { ic->recvd = id; ic->rstart = id; ilsendctl(s, nil, Ilack, ic->next, ic->recvd, 0); ic->state = Ilestablished; ic->fasttimeout = 0; ic->rexmit = 0; Fsconnected(s, nil); ilpullup(s); } break; case Ilclose: if(ack == ic->start) ilhangup(s, "connection rejected"); break; } freeblist(bp); break; case Ilsyncee: switch(h->iltype) { default: break; case Ilsync: if(id != ic->rstart || ack != 0){ illocalclose(s); } else { ic->recvd = id; ilsendctl(s, nil, Ilsync, ic->start, ic->recvd, 0); } break; case Ilack: if(ack == ic->start) { ic->state = Ilestablished; ic->fasttimeout = 0; ic->rexmit = 0; ilpullup(s); } break; case Ildata: if(ack == ic->start) { ic->state = Ilestablished; ic->fasttimeout = 0; ic->rexmit = 0; goto established; } break; case Ilclose: if(ack == ic->start) ilhangup(s, "remote close"); break; } freeblist(bp); break; case Ilestablished: established: switch(h->iltype) { case Ilsync: if(id != ic->rstart) ilhangup(s, "remote close"); else ilsendctl(s, nil, Ilack, ic->next, ic->rstart, 0); freeblist(bp); break; case Ildata: /* * avoid consuming all the mount rpc buffers in the * system. if the input queue is too long, drop this * packet. */ if (s->rq && qlen(s->rq) >= Maxrq) { priv->stats[DroppedMsgs]++; freeblist(bp); break; } ilackto(ic, ack, bp); iloutoforder(s, h, bp); ilpullup(s); break; case Ildataquery: ilackto(ic, ack, bp); iloutoforder(s, h, bp); ilpullup(s); ilsendctl(s, nil, Ilstate, ic->next, ic->recvd, h->ilspec); break; case Ilack: ilackto(ic, ack, bp); freeblist(bp); break; case Ilquery: ilackto(ic, ack, bp); ilsendctl(s, nil, Ilstate, ic->next, ic->recvd, h->ilspec); freeblist(bp); break; case Ilstate: if(ack >= ic->rttack) ic->rttack = 0; ilackto(ic, ack, bp); if(h->ilspec > Nqt) h->ilspec = 0; if(ic->qt[h->ilspec] > ack){ ilrexmit(ic); ilsettimeout(ic); } freeblist(bp); break; case Ilclose: freeblist(bp); if(ack < ic->start || ack > ic->next) break; ic->recvd = id; ilsendctl(s, nil, Ilclose, ic->next, ic->recvd, 0); ic->state = Ilclosing; ilsettimeout(ic); ilfreeq(ic); break; } break; case Illistening: freeblist(bp); break; case Ilclosing: switch(h->iltype) { case Ilclose: ic->recvd = id; ilsendctl(s, nil, Ilclose, ic->next, ic->recvd, 0); if(ack == ic->next) ilhangup(s, nil); break; default: break; } freeblist(bp); break; } } void ilrexmit(Ilcb *ic) { Ilhdr *h; Block *nb; Conv *c; ulong id; Ilpriv *priv; nb = nil; qlock(&ic->ackq); if(ic->unacked) nb = copyblock(ic->unacked, blocklen(ic->unacked)); qunlock(&ic->ackq); if(nb == nil) return; h = (Ilhdr*)nb->rp; h->vihl = IP_VER4; h->iltype = Ildataquery; hnputl(h->ilack, ic->recvd); h->ilspec = ilnextqt(ic); h->ilsum[0] = 0; h->ilsum[1] = 0; hnputs(h->ilsum, ptclcsum(nb, IL_IPSIZE, nhgets(h->illen))); c = ic->conv; id = nhgetl(h->ilid); netlog(c->p->f, Logil, "il: rexmit %lud %lud: %d %lud: %I %d/%d\n", id, ic->recvd, ic->rexmit, ic->timeout, c->raddr, c->lport, c->rport); ilbackoff(ic); ipoput4(c->p->f, nb, 0, c->ttl, c->tos, c); /* statistics */ ic->rxtot++; priv = c->p->priv; priv->rexmit++; } /* DEBUG */ void ilprocess(Conv *s, Ilhdr *h, Block *bp) { Ilcb *ic; ic = (Ilcb*)s->ptcl; USED(ic); netlog(s->p->f, Logilmsg, "%11s rcv %lud/%lud snt %lud/%lud pkt(%s id %d ack %ud %ud->%ud) ", ilstates[ic->state], ic->rstart, ic->recvd, ic->start, ic->next, iltype[h->iltype], nhgetl(h->ilid), nhgetl(h->ilack), nhgets(h->ilsrc), nhgets(h->ildst)); _ilprocess(s, h, bp); netlog(s->p->f, Logilmsg, "%11s rcv %lud snt %lud\n", ilstates[ic->state], ic->recvd, ic->next); } void ilhangup(Conv *s, char *msg) { Ilcb *ic; int callout; netlog(s->p->f, Logil, "il: hangup! %I %d/%d: %s\n", s->raddr, s->lport, s->rport, msg?msg:"no reason"); ic = (Ilcb*)s->ptcl; callout = ic->state == Ilsyncer; illocalclose(s); qhangup(s->rq, msg); qhangup(s->wq, msg); if(callout) Fsconnected(s, msg); } void ilpullup(Conv *s) { Ilcb *ic; Ilhdr *oh; Block *bp; ulong oid, dlen; Ilpriv *ipriv; ic = (Ilcb*)s->ptcl; if(ic->state != Ilestablished) return; qlock(&ic->outo); while(ic->outoforder) { bp = ic->outoforder; oh = (Ilhdr*)bp->rp; oid = nhgetl(oh->ilid); if(oid <= ic->recvd) { ic->outoforder = bp->list; freeblist(bp); continue; } if(oid != ic->recvd+1){ ipriv = s->p->priv; ipriv->stats[OutOfOrder]++; break; } ic->recvd = oid; ic->outoforder = bp->list; bp->list = nil; dlen = nhgets(oh->illen)-IL_HDRSIZE; bp = trimblock(bp, IL_IPSIZE+IL_HDRSIZE, dlen); /* * Upper levels don't know about multiple-block * messages so copy all into one (yick). */ qpass(s->rq, packblock(concatblock(bp))); } qunlock(&ic->outo); } void iloutoforder(Conv *s, Ilhdr *h, Block *bp) { Ilcb *ic; uchar *lid; Block *f, **l; ulong id, newid; Ilpriv *ipriv; ipriv = s->p->priv; ic = (Ilcb*)s->ptcl; bp->list = nil; id = nhgetl(h->ilid); /* Window checks */ if(id <= ic->recvd || id > ic->recvd+ic->window) { netlog(s->p->f, Logil, "il: message outside window %lud <%lud-%lud>: %I %d/%d\n", id, ic->recvd, ic->recvd+ic->window, s->raddr, s->lport, s->rport); freeblist(bp); return; } /* Packet is acceptable so sort onto receive queue for pullup */ qlock(&ic->outo); if(ic->outoforder == nil) ic->outoforder = bp; else { l = &ic->outoforder; for(f = *l; f; f = f->list) { lid = ((Ilhdr*)(f->rp))->ilid; newid = nhgetl(lid); if(id <= newid) { if(id == newid) { ipriv->stats[DupMsg]++; ipriv->stats[DupBytes] += blocklen(bp); qunlock(&ic->outo); freeblist(bp); return; } bp->list = f; *l = bp; qunlock(&ic->outo); return; } l = &f->list; } *l = bp; } qunlock(&ic->outo); } int ilsendctl(Conv *ipc, Ilhdr *inih, int type, ulong id, ulong ack, int ilspec) { Ilhdr *ih; Ilcb *ic; Block *bp; int ttl, tos; bp = allocb(IL_IPSIZE+IL_HDRSIZE); bp->wp += IL_IPSIZE+IL_HDRSIZE; ih = (Ilhdr *)(bp->rp); ih->vihl = IP_VER4; /* Ip fields */ ih->proto = IP_ILPROTO; hnputs(ih->illen, IL_HDRSIZE); ih->frag[0] = 0; ih->frag[1] = 0; if(inih) { hnputl(ih->dst, nhgetl(inih->src)); hnputl(ih->src, nhgetl(inih->dst)); hnputs(ih->ilsrc, nhgets(inih->ildst)); hnputs(ih->ildst, nhgets(inih->ilsrc)); hnputl(ih->ilid, nhgetl(inih->ilack)); hnputl(ih->ilack, nhgetl(inih->ilid)); ttl = MAXTTL; tos = DFLTTOS; } else { v6tov4(ih->dst, ipc->raddr); v6tov4(ih->src, ipc->laddr); hnputs(ih->ilsrc, ipc->lport); hnputs(ih->ildst, ipc->rport); hnputl(ih->ilid, id); hnputl(ih->ilack, ack); ic = (Ilcb*)ipc->ptcl; ic->acksent = ack; ic->acktime = NOW; ttl = ipc->ttl; tos = ipc->tos; } ih->iltype = type; ih->ilspec = ilspec; ih->ilsum[0] = 0; ih->ilsum[1] = 0; if(ilcksum) hnputs(ih->ilsum, ptclcsum(bp, IL_IPSIZE, IL_HDRSIZE)); if(ipc==nil) panic("ipc is nil caller is %#p", getcallerpc(&ipc)); if(ipc->p==nil) panic("ipc->p is nil"); netlog(ipc->p->f, Logilmsg, "ctl(%s id %d ack %d %d->%d)\n", iltype[ih->iltype], nhgetl(ih->ilid), nhgetl(ih->ilack), nhgets(ih->ilsrc), nhgets(ih->ildst)); return ipoput4(ipc->p->f, bp, 0, ttl, tos, ipc); } void ilreject(Fs *f, Ilhdr *inih) { Ilhdr *ih; Block *bp; bp = allocb(IL_IPSIZE+IL_HDRSIZE); bp->wp += IL_IPSIZE+IL_HDRSIZE; ih = (Ilhdr *)(bp->rp); ih->vihl = IP_VER4; /* Ip fields */ ih->proto = IP_ILPROTO; hnputs(ih->illen, IL_HDRSIZE); ih->frag[0] = 0; ih->frag[1] = 0; hnputl(ih->dst, nhgetl(inih->src)); hnputl(ih->src, nhgetl(inih->dst)); hnputs(ih->ilsrc, nhgets(inih->ildst)); hnputs(ih->ildst, nhgets(inih->ilsrc)); hnputl(ih->ilid, nhgetl(inih->ilack)); hnputl(ih->ilack, nhgetl(inih->ilid)); ih->iltype = Ilclose; ih->ilspec = 0; ih->ilsum[0] = 0; ih->ilsum[1] = 0; if(ilcksum) hnputs(ih->ilsum, ptclcsum(bp, IL_IPSIZE, IL_HDRSIZE)); ipoput4(f, bp, 0, MAXTTL, DFLTTOS, nil); } void ilsettimeout(Ilcb *ic) { ulong pt; pt = (ic->delay>>LogAGain) + ic->unackedbytes/(ic->rate>>LogAGain) + (ic->mdev>>(LogDGain-1)) + AckDelay; if(pt > MaxTimeout) pt = MaxTimeout; ic->timeout = NOW + pt; } void ilbackoff(Ilcb *ic) { ulong pt; int i; pt = (ic->delay>>LogAGain) + ic->unackedbytes/(ic->rate>>LogAGain) + (ic->mdev>>(LogDGain-1)) + AckDelay; for(i = 0; i < ic->rexmit; i++) pt = pt + (pt>>1); if(pt > MaxTimeout) pt = MaxTimeout; ic->timeout = NOW + pt; if(ic->fasttimeout) ic->timeout = NOW+Iltickms; ic->rexmit++; } // complain if two numbers not within an hour of each other #define Tfuture (1000*60*60) int later(ulong t1, ulong t2, char *x) { int dt; dt = t1 - t2; if(dt > 0) { if(x != nil && dt > Tfuture) print("%s: way future %d\n", x, dt); return 1; } if(dt < -Tfuture) { if(x != nil) print("%s: way past %d\n", x, -dt); return 1; } return 0; } void ilackproc(void *x) { Ilcb *ic; Conv **s, *p; Proto *il; il = x; while(waserror()) ; loop: tsleep(&up->sleep, return0, 0, Iltickms); for(s = il->conv; s && *s; s++) { p = *s; ic = (Ilcb*)p->ptcl; switch(ic->state) { case Ilclosed: case Illistening: break; case Ilclosing: if(later(NOW, ic->timeout, "timeout0")) { if(ic->rexmit > MaxRexmit){ ilhangup(p, nil); break; } ilsendctl(p, nil, Ilclose, ic->next, ic->recvd, 0); ilbackoff(ic); } break; case Ilsyncee: case Ilsyncer: if(later(NOW, ic->timeout, "timeout1")) { if(ic->rexmit > MaxRexmit){ ilhangup(p, etime); break; } ilsendctl(p, nil, Ilsync, ic->start, ic->recvd, 0); ilbackoff(ic); } break; case Ilestablished: if(ic->recvd != ic->acksent) if(later(NOW, ic->acktime, "acktime")) ilsendctl(p, nil, Ilack, ic->next, ic->recvd, 0); if(later(NOW, ic->querytime, "querytime")){ if(later(NOW, ic->lastrecv+DeathTime, "deathtime")){ netlog(il->f, Logil, "il: hangup: deathtime\n"); ilhangup(p, etime); break; } ilsendctl(p, nil, Ilquery, ic->next, ic->recvd, ilnextqt(ic)); ic->querytime = NOW + QueryTime; } if(ic->unacked != nil) if(later(NOW, ic->timeout, "timeout2")) { if(ic->rexmit > MaxRexmit){ netlog(il->f, Logil, "il: hangup: too many rexmits\n"); ilhangup(p, etime); break; } ilsendctl(p, nil, Ilquery, ic->next, ic->recvd, ilnextqt(ic)); ic->rxquery++; ilbackoff(ic); } break; } } goto loop; } void ilcbinit(Ilcb *ic) { ic->start = nrand(0x1000000); ic->next = ic->start+1; ic->recvd = 0; ic->window = Defaultwin; ic->unackedbytes = 0; ic->unacked = nil; ic->outoforder = nil; ic->rexmit = 0; ic->rxtot = 0; ic->rxquery = 0; ic->qtx = 1; ic->fasttimeout = 0; /* timers */ ic->delay = DefRtt<<LogAGain; ic->mdev = DefRtt<<LogDGain; ic->rate = DefByteRate<<LogAGain; ic->querytime = NOW + QueryTime; ic->lastrecv = NOW; /* or we'll timeout right away */ ilsettimeout(ic); } char* ilstart(Conv *c, int type, int fasttimeout) { Ilcb *ic; Ilpriv *ipriv; char kpname[KNAMELEN]; ipriv = c->p->priv; if(ipriv->ackprocstarted == 0){ qlock(&ipriv->apl); if(ipriv->ackprocstarted == 0){ sprint(kpname, "#I%dilack", c->p->f->dev); kproc(kpname, ilackproc, c->p); ipriv->ackprocstarted = 1; } qunlock(&ipriv->apl); } ic = (Ilcb*)c->ptcl; ic->conv = c; if(ic->state != Ilclosed) return nil; ilcbinit(ic); if(fasttimeout){ /* timeout if we can't connect quickly */ ic->fasttimeout = 1; ic->timeout = NOW+Iltickms; ic->rexmit = MaxRexmit - 4; }; switch(type) { default: netlog(c->p->f, Logil, "il: start: type %d\n", type); break; case IL_LISTEN: ic->state = Illistening; iphtadd(&ipriv->ht, c); break; case IL_CONNECT: ic->state = Ilsyncer; iphtadd(&ipriv->ht, c); if(ilsendctl(c, nil, Ilsync, ic->start, ic->recvd, 0) < 0) ilhangup(c, "no route"); break; } return nil; } void ilfreeq(Ilcb *ic) { Block *bp, *next; qlock(&ic->ackq); for(bp = ic->unacked; bp; bp = next) { next = bp->list; freeblist(bp); } ic->unacked = nil; qunlock(&ic->ackq); qlock(&ic->outo); for(bp = ic->outoforder; bp; bp = next) { next = bp->list; freeblist(bp); } ic->outoforder = nil; qunlock(&ic->outo); } void iladvise(Proto *il, Block *bp, char *msg) { Ilhdr *h; Ilcb *ic; uchar source[IPaddrlen], dest[IPaddrlen]; ushort psource; Conv *s, **p; h = (Ilhdr*)(bp->rp); v4tov6(dest, h->dst); v4tov6(source, h->src); psource = nhgets(h->ilsrc); /* Look for a connection, unfortunately the destination port is missing */ qlock(il); for(p = il->conv; *p; p++) { s = *p; if(s->lport == psource) if(ipcmp(s->laddr, source) == 0) if(ipcmp(s->raddr, dest) == 0){ if(s->ignoreadvice) break; qunlock(il); ic = (Ilcb*)s->ptcl; switch(ic->state){ case Ilsyncer: ilhangup(s, msg); break; } freeblist(bp); return; } } qunlock(il); freeblist(bp); } int ilnextqt(Ilcb *ic) { int x; qlock(&ic->ackq); x = ic->qtx; if(++x > Nqt) x = 1; ic->qtx = x; ic->qt[x] = ic->next-1; /* highest xmitted packet */ ic->qt[0] = ic->qt[x]; /* compatibility with old implementations */ qunlock(&ic->ackq); return x; } /* calculate scale constants that converts fast ticks to ms (more or less) */ static void inittimescale(void) { uvlong hz; fastticks(&hz); if(hz > 1000){ scalediv = hz/1000; scalemul = 1; } else { scalediv = 1; scalemul = 1000/hz; } } void ilinit(Fs *f) { Proto *il; inittimescale(); il = smalloc(sizeof(Proto)); il->priv = smalloc(sizeof(Ilpriv)); il->name = "il"; il->connect = ilconnect; il->announce = ilannounce; il->state = ilstate; il->create = ilcreate; il->close = ilclose; il->rcv = iliput; il->ctl = nil; il->advise = iladvise; il->stats = ilxstats; il->inuse = ilinuse; il->gc = nil; il->ipproto = IP_ILPROTO; il->nc = scalednconv(); il->ptclsize = sizeof(Ilcb); Fsproto(f, il); }