ref: a141f4c53a32d8227f9a490a8e4f7d87445c47d1
dir: /sys/src/9/ip/ipifc.c/
#include "u.h" #include "../port/lib.h" #include "mem.h" #include "dat.h" #include "fns.h" #include "../port/error.h" #include "ip.h" #include "ipv6.h" #define DPRINT if(0)print enum { Maxmedia = 32, Nself = Maxmedia*5, NHASH = 1<<6, NCACHE = 256, QMAX = 192*1024-1, }; Medium *media[Maxmedia] = { 0 }; /* * cache of local addresses (addresses we answer to) */ struct Ipself { uchar a[IPaddrlen]; Ipself *hnext; /* next address in the hash table */ Iplink *link; /* binding twixt Ipself and Ipifc */ ulong expire; uchar type; /* type of address */ int ref; Ipself *next; /* free list */ }; struct Ipselftab { QLock; int inited; int acceptall; /* true if an interface has the null address */ Ipself *hash[NHASH]; /* hash chains */ }; /* * Multicast addresses are chained onto a Chan so that * we can remove them when the Chan is closed. */ typedef struct Ipmcast Ipmcast; struct Ipmcast { Ipmcast *next; uchar ma[IPaddrlen]; /* multicast address */ uchar ia[IPaddrlen]; /* interface address */ }; /* quick hash for ip addresses */ #define hashipa(a) ( ( ((a)[IPaddrlen-2]<<8) | (a)[IPaddrlen-1] )%NHASH ) static char tifc[] = "ifc "; static void addselfcache(Fs *f, Ipifc *ifc, Iplifc *lifc, uchar *a, int type); static void remselfcache(Fs *f, Ipifc *ifc, Iplifc *lifc, uchar *a); static char* ipifcjoinmulti(Ipifc *ifc, char **argv, int argc); static char* ipifcleavemulti(Ipifc *ifc, char **argv, int argc); static void ipifcregisterproxy(Fs*, Ipifc*, uchar*); static char* ipifcremlifc(Ipifc*, Iplifc*); /* * link in a new medium */ void addipmedium(Medium *med) { int i; for(i = 0; i < nelem(media)-1; i++) if(media[i] == nil){ media[i] = med; break; } } /* * find the medium with this name */ Medium* ipfindmedium(char *name) { Medium **mp; for(mp = media; *mp != nil; mp++) if(strcmp((*mp)->name, name) == 0) break; return *mp; } /* * attach a device (or pkt driver) to the interface. * called with c locked */ static char* ipifcbind(Conv *c, char **argv, int argc) { Ipifc *ifc; Medium *m; if(argc < 2) return Ebadarg; ifc = (Ipifc*)c->ptcl; /* bind the device to the interface */ m = ipfindmedium(argv[1]); if(m == nil) return "unknown interface type"; wlock(ifc); if(ifc->m != nil){ wunlock(ifc); return "interface already bound"; } if(waserror()){ wunlock(ifc); nexterror(); } /* do medium specific binding */ (*m->bind)(ifc, argc, argv); /* set the bound device name */ if(argc > 2) strncpy(ifc->dev, argv[2], sizeof(ifc->dev)); else snprint(ifc->dev, sizeof ifc->dev, "%s%d", m->name, c->x); ifc->dev[sizeof(ifc->dev)-1] = 0; /* set up parameters */ ifc->m = m; ifc->mintu = ifc->m->mintu; ifc->maxtu = ifc->m->maxtu; if(ifc->m->unbindonclose == 0) ifc->conv->inuse++; ifc->rp.mflag = 0; /* default not managed */ ifc->rp.oflag = 0; ifc->rp.maxraint = 600000; /* millisecs */ ifc->rp.minraint = 200000; ifc->rp.linkmtu = 0; /* no mtu sent */ ifc->rp.reachtime = 0; ifc->rp.rxmitra = 0; ifc->rp.ttl = MAXTTL; ifc->rp.routerlt = 3 * ifc->rp.maxraint; /* any ancillary structures (like routes) no longer pertain */ ifc->ifcid++; /* reopen all the queues closed by a previous unbind */ qreopen(c->rq); qreopen(c->eq); qreopen(c->sq); wunlock(ifc); poperror(); return nil; } /* * detach a device from an interface, close the interface * called with ifc->conv closed */ static char* ipifcunbind(Ipifc *ifc) { char *err; wlock(ifc); if(waserror()){ wunlock(ifc); nexterror(); } /* disassociate logical interfaces (before zeroing ifc->arg) */ while(ifc->lifc){ err = ipifcremlifc(ifc, ifc->lifc); /* * note: err non-zero means lifc not found, * which can't happen in this case. */ if(err) error(err); } /* disassociate device */ if(ifc->m && ifc->m->unbind) (*ifc->m->unbind)(ifc); memset(ifc->dev, 0, sizeof(ifc->dev)); ifc->arg = nil; ifc->reassemble = 0; /* close queues to stop queuing of packets */ qclose(ifc->conv->rq); qclose(ifc->conv->wq); qclose(ifc->conv->sq); /* dissociate routes */ ifc->ifcid++; if(ifc->m != nil && ifc->m->unbindonclose == 0) ifc->conv->inuse--; ifc->m = nil; wunlock(ifc); poperror(); return nil; } char sfixedformat[] = "device %s maxtu %d sendra %d recvra %d mflag %d oflag" " %d maxraint %d minraint %d linkmtu %d reachtime %d rxmitra %d ttl %d routerlt" " %d pktin %lud pktout %lud errin %lud errout %lud\n"; char slineformat[] = " %-40I %-10M %-40I %-12lud %-12lud\n"; static int ipifcstate(Conv *c, char *state, int n) { Ipifc *ifc; Iplifc *lifc; int m; ifc = (Ipifc*)c->ptcl; m = snprint(state, n, sfixedformat, ifc->dev, ifc->maxtu, ifc->sendra6, ifc->recvra6, ifc->rp.mflag, ifc->rp.oflag, ifc->rp.maxraint, ifc->rp.minraint, ifc->rp.linkmtu, ifc->rp.reachtime, ifc->rp.rxmitra, ifc->rp.ttl, ifc->rp.routerlt, ifc->in, ifc->out, ifc->inerr, ifc->outerr); rlock(ifc); for(lifc = ifc->lifc; lifc && n > m; lifc = lifc->next) m += snprint(state+m, n - m, slineformat, lifc->local, lifc->mask, lifc->remote, lifc->validlt, lifc->preflt); if(ifc->lifc == nil) m += snprint(state+m, n - m, "\n"); runlock(ifc); return m; } static int ipifclocal(Conv *c, char *state, int n) { Ipifc *ifc; Iplifc *lifc; Iplink *link; int m; ifc = (Ipifc*)c->ptcl; m = 0; rlock(ifc); for(lifc = ifc->lifc; lifc; lifc = lifc->next){ m += snprint(state+m, n - m, "%-40.40I ->", lifc->local); for(link = lifc->link; link; link = link->lifclink) m += snprint(state+m, n - m, " %-40.40I", link->self->a); m += snprint(state+m, n - m, "\n"); } runlock(ifc); return m; } static int ipifcinuse(Conv *c) { Ipifc *ifc; ifc = (Ipifc*)c->ptcl; return ifc->m != nil; } /* * called when a process writes to an interface's 'data' */ static void ipifckick(void *x) { Conv *c = x; Block *bp; Ipifc *ifc; bp = qget(c->wq); if(bp == nil) return; ifc = (Ipifc*)c->ptcl; if(!canrlock(ifc)){ freeb(bp); return; } if(waserror()){ runlock(ifc); nexterror(); } if(ifc->m && ifc->m->pktin) (*ifc->m->pktin)(c->p->f, ifc, bp); else freeb(bp); runlock(ifc); poperror(); } /* * called when a new ipifc structure is created */ static void ipifccreate(Conv *c) { Ipifc *ifc; c->rq = qopen(QMAX, 0, 0, 0); c->wq = qopen(QMAX, Qkick, ipifckick, c); c->sq = qopen(QMAX, 0, 0, 0); if(c->rq == nil || c->wq == nil || c->sq == nil) error(Enomem); ifc = (Ipifc*)c->ptcl; ifc->conv = c; ifc->unbinding = 0; ifc->m = nil; ifc->reassemble = 0; } /* * called after last close of ipifc data or ctl * called with c locked, we must unlock */ static void ipifcclose(Conv *c) { Ipifc *ifc; Medium *m; ifc = (Ipifc*)c->ptcl; m = ifc->m; if(m && m->unbindonclose) ipifcunbind(ifc); } /* * change an interface's mtu */ char* ipifcsetmtu(Ipifc *ifc, char **argv, int argc) { int mtu; if(argc < 2 || ifc->m == nil) return Ebadarg; mtu = strtoul(argv[1], 0, 0); if(mtu < ifc->m->mintu || mtu > ifc->m->maxtu) return Ebadarg; ifc->maxtu = mtu; return nil; } /* * add an address to an interface. */ char* ipifcadd(Ipifc *ifc, char **argv, int argc, int tentative, Iplifc *lifcp) { int i, type, mtu, sendnbrdisc = 0; uchar ip[IPaddrlen], mask[IPaddrlen], rem[IPaddrlen]; uchar bcast[IPaddrlen], net[IPaddrlen]; Iplifc *lifc, **l; Fs *f; if(ifc->m == nil) return "ipifc not yet bound to device"; f = ifc->conv->p->f; type = Rifc; memset(ip, 0, IPaddrlen); memset(mask, 0, IPaddrlen); memset(rem, 0, IPaddrlen); switch(argc){ case 6: if(strcmp(argv[5], "proxy") == 0) type |= Rproxy; /* fall through */ case 5: mtu = strtoul(argv[4], 0, 0); if(mtu >= ifc->m->mintu && mtu <= ifc->m->maxtu) ifc->maxtu = mtu; /* fall through */ case 4: if (parseip(ip, argv[1]) == -1 || parseip(rem, argv[3]) == -1) return Ebadip; parseipmask(mask, argv[2]); maskip(rem, mask, net); break; case 3: if (parseip(ip, argv[1]) == -1) return Ebadip; parseipmask(mask, argv[2]); maskip(ip, mask, rem); maskip(rem, mask, net); break; case 2: if (parseip(ip, argv[1]) == -1) return Ebadip; memmove(mask, defmask(ip), IPaddrlen); maskip(ip, mask, rem); maskip(rem, mask, net); break; default: return Ebadarg; } if(isv4(ip)) tentative = 0; wlock(ifc); if(waserror()){ wunlock(ifc); nexterror(); } /* ignore if this is already a local address for this ifc */ for(lifc = ifc->lifc; lifc; lifc = lifc->next) { if(ipcmp(lifc->local, ip) == 0) { if(lifc->tentative != tentative) lifc->tentative = tentative; if(lifcp) { lifc->onlink = lifcp->onlink; lifc->autoflag = lifcp->autoflag; lifc->validlt = lifcp->validlt; lifc->preflt = lifcp->preflt; lifc->origint = lifcp->origint; } goto out; } } /* add the address to the list of logical ifc's for this ifc */ lifc = smalloc(sizeof(Iplifc)); ipmove(lifc->local, ip); ipmove(lifc->mask, mask); ipmove(lifc->remote, rem); ipmove(lifc->net, net); lifc->tentative = tentative; if(lifcp) { lifc->onlink = lifcp->onlink; lifc->autoflag = lifcp->autoflag; lifc->validlt = lifcp->validlt; lifc->preflt = lifcp->preflt; lifc->origint = lifcp->origint; } else { /* default values */ lifc->onlink = lifc->autoflag = 1; lifc->validlt = lifc->preflt = ~0L; lifc->origint = NOW / 1000; } lifc->next = nil; for(l = &ifc->lifc; *l; l = &(*l)->next) ; *l = lifc; /* check for point-to-point interface */ if(ipcmp(ip, v6loopback)) /* skip v6 loopback, it's a special address */ if(ipcmp(mask, IPallbits) == 0) type |= Rptpt; /* add local routes */ if(isv4(ip)) v4addroute(f, tifc, rem+IPv4off, mask+IPv4off, rem+IPv4off, type); else v6addroute(f, tifc, rem, mask, rem, type); addselfcache(f, ifc, lifc, ip, Runi); if((type & (Rproxy|Rptpt)) == (Rproxy|Rptpt)){ ipifcregisterproxy(f, ifc, rem); goto out; } if(isv4(ip) || ipcmp(ip, IPnoaddr) == 0) { /* add subnet directed broadcast address to the self cache */ for(i = 0; i < IPaddrlen; i++) bcast[i] = (ip[i] & mask[i]) | ~mask[i]; addselfcache(f, ifc, lifc, bcast, Rbcast); /* add subnet directed network address to the self cache */ for(i = 0; i < IPaddrlen; i++) bcast[i] = (ip[i] & mask[i]) & mask[i]; addselfcache(f, ifc, lifc, bcast, Rbcast); /* add network directed broadcast address to the self cache */ memmove(mask, defmask(ip), IPaddrlen); for(i = 0; i < IPaddrlen; i++) bcast[i] = (ip[i] & mask[i]) | ~mask[i]; addselfcache(f, ifc, lifc, bcast, Rbcast); /* add network directed network address to the self cache */ memmove(mask, defmask(ip), IPaddrlen); for(i = 0; i < IPaddrlen; i++) bcast[i] = (ip[i] & mask[i]) & mask[i]; addselfcache(f, ifc, lifc, bcast, Rbcast); addselfcache(f, ifc, lifc, IPv4bcast, Rbcast); } else { if(ipcmp(ip, v6loopback) == 0) { /* add node-local mcast address */ addselfcache(f, ifc, lifc, v6allnodesN, Rmulti); /* add route for all node multicast */ v6addroute(f, tifc, v6allnodesN, v6allnodesNmask, v6allnodesN, Rmulti); } /* add all nodes multicast address */ addselfcache(f, ifc, lifc, v6allnodesL, Rmulti); /* add route for all nodes multicast */ v6addroute(f, tifc, v6allnodesL, v6allnodesLmask, v6allnodesL, Rmulti); /* add solicited-node multicast address */ ipv62smcast(bcast, ip); addselfcache(f, ifc, lifc, bcast, Rmulti); sendnbrdisc = 1; } /* register the address on this network for address resolution */ if(isv4(ip) && ifc->m->areg) (*ifc->m->areg)(ifc, ip); out: wunlock(ifc); poperror(); if(!isv4(ip) && ipcmp(ip, IPnoaddr) != 0){ if(!tentative) arpenter(f, V6, ip, ifc->mac, 6, 0); else if(sendnbrdisc) icmpns(f, 0, SRC_UNSPEC, ip, TARG_MULTI, ifc->mac); } return nil; } /* * remove a logical interface from an ifc * always called with ifc wlock'd */ static char* ipifcremlifc(Ipifc *ifc, Iplifc *lifc) { Iplifc **l; Fs *f; f = ifc->conv->p->f; /* * find address on this interface and remove from chain. * for pt to pt we actually specify the remote address as the * addresss to remove. */ for(l = &ifc->lifc; *l != nil && *l != lifc; l = &(*l)->next) ; if(*l == nil) return "address not on this interface"; *l = lifc->next; /* disassociate any addresses */ while(lifc->link) remselfcache(f, ifc, lifc, lifc->link->self->a); /* remove the route for this logical interface */ if(isv4(lifc->local)) v4delroute(f, lifc->remote+IPv4off, lifc->mask+IPv4off, 1); else { v6delroute(f, lifc->remote, lifc->mask, 1); if(ipcmp(lifc->local, v6loopback) == 0) /* remove route for all node multicast */ v6delroute(f, v6allnodesN, v6allnodesNmask, 1); else if(memcmp(lifc->local, v6linklocal, v6llpreflen) == 0) /* remove route for all link multicast */ v6delroute(f, v6allnodesL, v6allnodesLmask, 1); } free(lifc); return nil; } /* * remove an address from an interface. * called with c->car locked */ char* ipifcrem(Ipifc *ifc, char **argv, int argc) { char *rv; uchar ip[IPaddrlen], mask[IPaddrlen], rem[IPaddrlen]; Iplifc *lifc; if(argc < 3) return Ebadarg; if (parseip(ip, argv[1]) == -1) return Ebadip; parseipmask(mask, argv[2]); if(argc < 4) maskip(ip, mask, rem); else if (parseip(rem, argv[3]) == -1) return Ebadip; /* * find address on this interface and remove from chain. * for pt to pt we actually specify the remote address as the * addresss to remove. */ wlock(ifc); for(lifc = ifc->lifc; lifc != nil; lifc = lifc->next) { if (memcmp(ip, lifc->local, IPaddrlen) == 0 && memcmp(mask, lifc->mask, IPaddrlen) == 0 && memcmp(rem, lifc->remote, IPaddrlen) == 0) break; } rv = ipifcremlifc(ifc, lifc); wunlock(ifc); return rv; } /* * distribute routes to active interfaces like the * TRIP linecards */ void ipifcaddroute(Fs *f, int vers, uchar *addr, uchar *mask, uchar *gate, int type) { Medium *m; Conv **cp, **e; Ipifc *ifc; e = &f->ipifc->conv[f->ipifc->nc]; for(cp = f->ipifc->conv; cp < e; cp++){ if(*cp != nil) { ifc = (Ipifc*)(*cp)->ptcl; m = ifc->m; if(m && m->addroute) (*m->addroute)(ifc, vers, addr, mask, gate, type); } } } void ipifcremroute(Fs *f, int vers, uchar *addr, uchar *mask) { Medium *m; Conv **cp, **e; Ipifc *ifc; e = &f->ipifc->conv[f->ipifc->nc]; for(cp = f->ipifc->conv; cp < e; cp++){ if(*cp != nil) { ifc = (Ipifc*)(*cp)->ptcl; m = ifc->m; if(m && m->remroute){ if(!waserror()){ (*m->remroute)(ifc, vers, addr, mask); poperror(); } } } } } /* * associate an address with the interface. This wipes out any previous * addresses. This is a macro that means, remove all the old interfaces * and add a new one. */ static char* ipifcconnect(Conv* c, char **argv, int argc) { char *err; Ipifc *ifc; ifc = (Ipifc*)c->ptcl; if(ifc->m == nil) return "ipifc not yet bound to device"; wlock(ifc); while(ifc->lifc){ err = ipifcremlifc(ifc, ifc->lifc); if(err){ wunlock(ifc); return err; } } wunlock(ifc); err = ipifcadd(ifc, argv, argc, 0, nil); if(err) return err; Fsconnected(c, nil); return nil; } char* ipifcra6(Ipifc *ifc, char **argv, int argc) { int i, argsleft, vmax = ifc->rp.maxraint, vmin = ifc->rp.minraint; argsleft = argc - 1; i = 1; if(argsleft % 2 != 0) return Ebadarg; while (argsleft > 1) { if(strcmp(argv[i], "recvra") == 0) ifc->recvra6 = (atoi(argv[i+1]) != 0); else if(strcmp(argv[i], "sendra") == 0) ifc->sendra6 = (atoi(argv[i+1]) != 0); else if(strcmp(argv[i], "mflag") == 0) ifc->rp.mflag = (atoi(argv[i+1]) != 0); else if(strcmp(argv[i], "oflag") == 0) ifc->rp.oflag = (atoi(argv[i+1]) != 0); else if(strcmp(argv[i], "maxraint") == 0) ifc->rp.maxraint = atoi(argv[i+1]); else if(strcmp(argv[i], "minraint") == 0) ifc->rp.minraint = atoi(argv[i+1]); else if(strcmp(argv[i], "linkmtu") == 0) ifc->rp.linkmtu = atoi(argv[i+1]); else if(strcmp(argv[i], "reachtime") == 0) ifc->rp.reachtime = atoi(argv[i+1]); else if(strcmp(argv[i], "rxmitra") == 0) ifc->rp.rxmitra = atoi(argv[i+1]); else if(strcmp(argv[i], "ttl") == 0) ifc->rp.ttl = atoi(argv[i+1]); else if(strcmp(argv[i], "routerlt") == 0) ifc->rp.routerlt = atoi(argv[i+1]); else return Ebadarg; argsleft -= 2; i += 2; } /* consistency check */ if(ifc->rp.maxraint < ifc->rp.minraint) { ifc->rp.maxraint = vmax; ifc->rp.minraint = vmin; return Ebadarg; } return nil; } /* * non-standard control messages. * called with c->car locked. */ static char* ipifcctl(Conv* c, char**argv, int argc) { Ipifc *ifc; int i; ifc = (Ipifc*)c->ptcl; if(strcmp(argv[0], "add") == 0) return ipifcadd(ifc, argv, argc, 0, nil); else if(strcmp(argv[0], "try") == 0) return ipifcadd(ifc, argv, argc, 1, nil); else if(strcmp(argv[0], "remove") == 0) return ipifcrem(ifc, argv, argc); else if(strcmp(argv[0], "unbind") == 0) return ipifcunbind(ifc); else if(strcmp(argv[0], "joinmulti") == 0) return ipifcjoinmulti(ifc, argv, argc); else if(strcmp(argv[0], "leavemulti") == 0) return ipifcleavemulti(ifc, argv, argc); else if(strcmp(argv[0], "mtu") == 0) return ipifcsetmtu(ifc, argv, argc); else if(strcmp(argv[0], "reassemble") == 0){ ifc->reassemble = 1; return nil; } else if(strcmp(argv[0], "iprouting") == 0){ i = 1; if(argc > 1) i = atoi(argv[1]); iprouting(c->p->f, i); return nil; } else if(strcmp(argv[0], "add6") == 0) return ipifcadd6(ifc, argv, argc); else if(strcmp(argv[0], "ra6") == 0) return ipifcra6(ifc, argv, argc); return "unsupported ctl"; } int ipifcstats(Proto *ipifc, char *buf, int len) { return ipstats(ipifc->f, buf, len); } void ipifcinit(Fs *f) { Proto *ipifc; ipifc = smalloc(sizeof(Proto)); ipifc->name = "ipifc"; ipifc->connect = ipifcconnect; ipifc->announce = nil; ipifc->bind = ipifcbind; ipifc->state = ipifcstate; ipifc->create = ipifccreate; ipifc->close = ipifcclose; ipifc->rcv = nil; ipifc->ctl = ipifcctl; ipifc->advise = nil; ipifc->stats = ipifcstats; ipifc->inuse = ipifcinuse; ipifc->local = ipifclocal; ipifc->ipproto = -1; ipifc->nc = Maxmedia; ipifc->ptclsize = sizeof(Ipifc); f->ipifc = ipifc; /* hack for ipifcremroute, findipifc, ... */ f->self = smalloc(sizeof(Ipselftab)); /* hack for ipforme */ Fsproto(f, ipifc); } /* * add to self routing cache * called with c->car locked */ static void addselfcache(Fs *f, Ipifc *ifc, Iplifc *lifc, uchar *a, int type) { Ipself *p; Iplink *lp; int h; qlock(f->self); if(waserror()){ qunlock(f->self); nexterror(); } /* see if the address already exists */ h = hashipa(a); for(p = f->self->hash[h]; p; p = p->next) if(memcmp(a, p->a, IPaddrlen) == 0) break; /* allocate a local address and add to hash chain */ if(p == nil){ p = smalloc(sizeof(*p)); ipmove(p->a, a); p->type = type; p->next = f->self->hash[h]; f->self->hash[h] = p; /* if the null address, accept all packets */ if(ipcmp(a, v4prefix) == 0 || ipcmp(a, IPnoaddr) == 0) f->self->acceptall = 1; } /* look for a link for this lifc */ for(lp = p->link; lp; lp = lp->selflink) if(lp->lifc == lifc) break; /* allocate a lifc-to-local link and link to both */ if(lp == nil){ lp = smalloc(sizeof(*lp)); lp->ref = 1; lp->lifc = lifc; lp->self = p; lp->selflink = p->link; p->link = lp; lp->lifclink = lifc->link; lifc->link = lp; /* add to routing table */ if(isv4(a)) v4addroute(f, tifc, a+IPv4off, IPallbits+IPv4off, a+IPv4off, type); else v6addroute(f, tifc, a, IPallbits, a, type); if((type & Rmulti) && ifc->m->addmulti) (*ifc->m->addmulti)(ifc, a, lifc->local); } else lp->ref++; qunlock(f->self); poperror(); } /* * These structures are unlinked from their chains while * other threads may be using them. To avoid excessive locking, * just put them aside for a while before freeing them. * called with f->self locked */ static Iplink *freeiplink; static Ipself *freeipself; static void iplinkfree(Iplink *p) { Iplink **l, *np; ulong now = NOW; l = &freeiplink; for(np = *l; np; np = *l){ if(np->expire > now){ *l = np->next; free(np); continue; } l = &np->next; } p->expire = now + 5000; /* give other threads 5 secs to get out */ p->next = nil; *l = p; } static void ipselffree(Ipself *p) { Ipself **l, *np; ulong now = NOW; l = &freeipself; for(np = *l; np; np = *l){ if(np->expire > now){ *l = np->next; free(np); continue; } l = &np->next; } p->expire = now + 5000; /* give other threads 5 secs to get out */ p->next = nil; *l = p; } /* * Decrement reference for this address on this link. * Unlink from selftab if this is the last ref. * called with c->car locked */ static void remselfcache(Fs *f, Ipifc *ifc, Iplifc *lifc, uchar *a) { Ipself *p, **l; Iplink *link, **l_self, **l_lifc; qlock(f->self); /* find the unique selftab entry */ l = &f->self->hash[hashipa(a)]; for(p = *l; p; p = *l){ if(ipcmp(p->a, a) == 0) break; l = &p->next; } if(p == nil) goto out; /* * walk down links from an ifc looking for one * that matches the selftab entry */ l_lifc = &lifc->link; for(link = *l_lifc; link; link = *l_lifc){ if(link->self == p) break; l_lifc = &link->lifclink; } if(link == nil) goto out; /* * walk down the links from the selftab looking for * the one we just found */ l_self = &p->link; for(link = *l_self; link; link = *l_self){ if(link == *l_lifc) break; l_self = &link->selflink; } if(link == nil) panic("remselfcache"); if(--(link->ref) != 0) goto out; if((p->type & Rmulti) && ifc->m->remmulti){ if(!waserror()){ (*ifc->m->remmulti)(ifc, a, lifc->local); poperror(); } } /* ref == 0, remove from both chains and free the link */ *l_lifc = link->lifclink; *l_self = link->selflink; iplinkfree(link); if(p->link != nil) goto out; /* remove from routing table */ if(isv4(a)) v4delroute(f, a+IPv4off, IPallbits+IPv4off, 1); else v6delroute(f, a, IPallbits, 1); /* no more links, remove from hash and free */ *l = p->next; ipselffree(p); /* if IPnoaddr, forget */ if(ipcmp(a, v4prefix) == 0 || ipcmp(a, IPnoaddr) == 0) f->self->acceptall = 0; out: qunlock(f->self); } static char *stformat = "%-44.44I %2.2d %4.4s\n"; enum { Nstformat= 41, }; long ipselftabread(Fs *f, char *cp, ulong offset, int n) { int i, m, nifc, off; Ipself *p; Iplink *link; char state[8]; m = 0; off = offset; qlock(f->self); for(i = 0; i < NHASH && m < n; i++){ for(p = f->self->hash[i]; p != nil && m < n; p = p->next){ nifc = 0; for(link = p->link; link; link = link->selflink) nifc++; routetype(p->type, state); m += snprint(cp + m, n - m, stformat, p->a, nifc, state); if(off > 0){ off -= m; m = 0; } } } qunlock(f->self); return m; } int iptentative(Fs *f, uchar *addr) { Ipself *p; p = f->self->hash[hashipa(addr)]; for(; p; p = p->next){ if(ipcmp(addr, p->a) == 0) return p->link->lifc->tentative; } return 0; } /* * returns * 0 - no match * Runi * Rbcast * Rmcast */ int ipforme(Fs *f, uchar *addr) { Ipself *p; p = f->self->hash[hashipa(addr)]; for(; p; p = p->next){ if(ipcmp(addr, p->a) == 0) return p->type; } /* hack to say accept anything */ if(f->self->acceptall) return Runi; return 0; } /* * find the ifc on same net as the remote system. If none, * return nil. */ Ipifc* findipifc(Fs *f, uchar *remote, int type) { Ipifc *ifc, *x; Iplifc *lifc; Conv **cp, **e; uchar gnet[IPaddrlen], xmask[IPaddrlen]; x = nil; memset(xmask, 0, IPaddrlen); /* find most specific match */ e = &f->ipifc->conv[f->ipifc->nc]; for(cp = f->ipifc->conv; cp < e; cp++){ if(*cp == 0) continue; ifc = (Ipifc*)(*cp)->ptcl; for(lifc = ifc->lifc; lifc; lifc = lifc->next){ maskip(remote, lifc->mask, gnet); if(ipcmp(gnet, lifc->net) == 0){ if(x == nil || ipcmp(lifc->mask, xmask) > 0){ x = ifc; ipmove(xmask, lifc->mask); } } } } if(x != nil) return x; /* for now for broadcast and multicast, just use first interface */ if(type & (Rbcast|Rmulti)){ for(cp = f->ipifc->conv; cp < e; cp++){ if(*cp == 0) continue; ifc = (Ipifc*)(*cp)->ptcl; if(ifc->lifc != nil) return ifc; } } return nil; } enum { unknownv6, /* UGH */ // multicastv6, unspecifiedv6, linklocalv6, globalv6, }; int v6addrtype(uchar *addr) { if(isv4(addr) || ipcmp(addr, IPnoaddr) == 0) return unknownv6; else if(islinklocal(addr) || isv6mcast(addr) && (addr[1] & 0xF) <= Link_local_scop) return linklocalv6; else return globalv6; } #define v6addrcurr(lifc) ((lifc)->preflt == ~0L || \ (lifc)->origint + (lifc)->preflt >= NOW/1000) static void findprimaryipv6(Fs *f, uchar *local) { int atype, atypel; Conv **cp, **e; Ipifc *ifc; Iplifc *lifc; ipmove(local, v6Unspecified); atype = unspecifiedv6; /* * find "best" (global > link local > unspecified) * local address; address must be current. */ e = &f->ipifc->conv[f->ipifc->nc]; for(cp = f->ipifc->conv; cp < e; cp++){ if(*cp == 0) continue; ifc = (Ipifc*)(*cp)->ptcl; for(lifc = ifc->lifc; lifc; lifc = lifc->next){ atypel = v6addrtype(lifc->local); if(atypel > atype && v6addrcurr(lifc)) { ipmove(local, lifc->local); atype = atypel; if(atype == globalv6) return; } } } } /* * returns first ip address configured */ static void findprimaryipv4(Fs *f, uchar *local) { Conv **cp, **e; Ipifc *ifc; Iplifc *lifc; /* find first ifc local address */ e = &f->ipifc->conv[f->ipifc->nc]; for(cp = f->ipifc->conv; cp < e; cp++){ if(*cp == 0) continue; ifc = (Ipifc*)(*cp)->ptcl; if((lifc = ifc->lifc) != nil){ ipmove(local, lifc->local); return; } } } /* * find the local address 'closest' to the remote system, copy it to * local and return the ifc for that address */ void findlocalip(Fs *f, uchar *local, uchar *remote) { int version, atype = unspecifiedv6, atypel = unknownv6; int atyper, deprecated; uchar gate[IPaddrlen], gnet[IPaddrlen]; Ipifc *ifc; Iplifc *lifc; Route *r; USED(atype); USED(atypel); qlock(f->ipifc); r = v6lookup(f, remote, nil); version = (memcmp(remote, v4prefix, IPv4off) == 0)? V4: V6; if(r != nil){ ifc = r->ifc; if(r->type & Rv4) v4tov6(gate, r->v4.gate); else { ipmove(gate, r->v6.gate); ipmove(local, v6Unspecified); } switch(version) { case V4: /* find ifc address closest to the gateway to use */ for(lifc = ifc->lifc; lifc; lifc = lifc->next){ maskip(gate, lifc->mask, gnet); if(ipcmp(gnet, lifc->net) == 0){ ipmove(local, lifc->local); goto out; } } break; case V6: /* find ifc address with scope matching the destination */ atyper = v6addrtype(remote); deprecated = 0; for(lifc = ifc->lifc; lifc; lifc = lifc->next){ atypel = v6addrtype(lifc->local); /* prefer appropriate scope */ if(atypel > atype && atype < atyper || atypel < atype && atype > atyper){ ipmove(local, lifc->local); deprecated = !v6addrcurr(lifc); atype = atypel; } else if(atypel == atype){ /* avoid deprecated addresses */ if(deprecated && v6addrcurr(lifc)){ ipmove(local, lifc->local); atype = atypel; deprecated = 0; } } if(atype == atyper && !deprecated) goto out; } if(atype >= atyper) goto out; break; default: panic("findlocalip: version %d", version); } } switch(version){ case V4: findprimaryipv4(f, local); break; case V6: findprimaryipv6(f, local); break; default: panic("findlocalip2: version %d", version); } out: qunlock(f->ipifc); } /* * return first v4 address associated with an interface */ int ipv4local(Ipifc *ifc, uchar *addr) { Iplifc *lifc; for(lifc = ifc->lifc; lifc; lifc = lifc->next){ if(isv4(lifc->local)){ memmove(addr, lifc->local+IPv4off, IPv4addrlen); return 1; } } return 0; } /* * return first v6 address associated with an interface */ int ipv6local(Ipifc *ifc, uchar *addr) { Iplifc *lifc; for(lifc = ifc->lifc; lifc; lifc = lifc->next){ if(!isv4(lifc->local) && !(lifc->tentative)){ ipmove(addr, lifc->local); return 1; } } return 0; } int ipv6anylocal(Ipifc *ifc, uchar *addr) { Iplifc *lifc; for(lifc = ifc->lifc; lifc; lifc = lifc->next){ if(!isv4(lifc->local)){ ipmove(addr, lifc->local); return SRC_UNI; } } return SRC_UNSPEC; } /* * see if this address is bound to the interface */ Iplifc* iplocalonifc(Ipifc *ifc, uchar *ip) { Iplifc *lifc; for(lifc = ifc->lifc; lifc; lifc = lifc->next) if(ipcmp(ip, lifc->local) == 0) return lifc; return nil; } /* * See if we're proxying for this address on this interface */ int ipproxyifc(Fs *f, Ipifc *ifc, uchar *ip) { Route *r; uchar net[IPaddrlen]; Iplifc *lifc; /* see if this is a direct connected pt to pt address */ r = v6lookup(f, ip, nil); if(r == nil || (r->type & (Rifc|Rproxy)) != (Rifc|Rproxy)) return 0; /* see if this is on the right interface */ for(lifc = ifc->lifc; lifc; lifc = lifc->next){ maskip(ip, lifc->mask, net); if(ipcmp(net, lifc->remote) == 0) return 1; } return 0; } /* * return multicast version if any */ int ipismulticast(uchar *ip) { if(isv4(ip)){ if(ip[IPv4off] >= 0xe0 && ip[IPv4off] < 0xf0) return V4; } else if(ip[0] == 0xff) return V6; return 0; } int ipisbm(uchar *ip) { if(isv4(ip)){ if(ip[IPv4off] >= 0xe0 && ip[IPv4off] < 0xf0) return V4; else if(ipcmp(ip, IPv4bcast) == 0) return V4; } else if(ip[0] == 0xff) return V6; return 0; } /* * add a multicast address to an interface, called with c->car locked */ void ipifcaddmulti(Conv *c, uchar *ma, uchar *ia) { Ipifc *ifc; Iplifc *lifc; Conv **p; Ipmulti *multi, **l; Fs *f; f = c->p->f; for(l = &c->multi; *l; l = &(*l)->next) if(ipcmp(ma, (*l)->ma) == 0 && ipcmp(ia, (*l)->ia) == 0) return; /* it's already there */ multi = *l = smalloc(sizeof(*multi)); ipmove(multi->ma, ma); ipmove(multi->ia, ia); multi->next = nil; for(p = f->ipifc->conv; *p; p++){ if((*p)->inuse == 0) continue; ifc = (Ipifc*)(*p)->ptcl; wlock(ifc); if(waserror()){ wunlock(ifc); nexterror(); } for(lifc = ifc->lifc; lifc; lifc = lifc->next) if(ipcmp(ia, lifc->local) == 0) addselfcache(f, ifc, lifc, ma, Rmulti); wunlock(ifc); poperror(); } } /* * remove a multicast address from an interface, called with c->car locked */ void ipifcremmulti(Conv *c, uchar *ma, uchar *ia) { Ipmulti *multi, **l; Iplifc *lifc; Conv **p; Ipifc *ifc; Fs *f; f = c->p->f; for(l = &c->multi; *l; l = &(*l)->next) if(ipcmp(ma, (*l)->ma) == 0 && ipcmp(ia, (*l)->ia) == 0) break; multi = *l; if(multi == nil) return; /* we don't have it open */ *l = multi->next; for(p = f->ipifc->conv; *p; p++){ if((*p)->inuse == 0) continue; ifc = (Ipifc*)(*p)->ptcl; wlock(ifc); for(lifc = ifc->lifc; lifc; lifc = lifc->next) if(ipcmp(ia, lifc->local) == 0) remselfcache(f, ifc, lifc, ma); wunlock(ifc); } free(multi); } /* * make lifc's join and leave multicast groups */ static char* ipifcjoinmulti(Ipifc *ifc, char **argv, int argc) { USED(ifc, argv, argc); return nil; } static char* ipifcleavemulti(Ipifc *ifc, char **argv, int argc) { USED(ifc, argv, argc); return nil; } static void ipifcregisterproxy(Fs *f, Ipifc *ifc, uchar *ip) { Conv **cp, **e; Ipifc *nifc; Iplifc *lifc; Medium *m; uchar net[IPaddrlen]; /* register the address on any network that will proxy for us */ e = &f->ipifc->conv[f->ipifc->nc]; if(!isv4(ip)) { /* V6 */ for(cp = f->ipifc->conv; cp < e; cp++){ if(*cp == nil || (nifc = (Ipifc*)(*cp)->ptcl) == ifc) continue; rlock(nifc); m = nifc->m; if(m == nil || m->addmulti == nil) { runlock(nifc); continue; } if(waserror()){ runlock(nifc); nexterror(); } for(lifc = nifc->lifc; lifc; lifc = lifc->next){ maskip(ip, lifc->mask, net); if(ipcmp(net, lifc->remote) == 0) { /* add solicited-node multicast addr */ ipv62smcast(net, ip); addselfcache(f, nifc, lifc, net, Rmulti); arpenter(f, V6, ip, nifc->mac, 6, 0); break; } } runlock(nifc); poperror(); } } else { /* V4 */ for(cp = f->ipifc->conv; cp < e; cp++){ if(*cp == nil || (nifc = (Ipifc*)(*cp)->ptcl) == ifc) continue; rlock(nifc); m = nifc->m; if(m == nil || m->areg == nil){ runlock(nifc); continue; } if(waserror()){ runlock(nifc); nexterror(); } for(lifc = nifc->lifc; lifc; lifc = lifc->next){ maskip(ip, lifc->mask, net); if(ipcmp(net, lifc->remote) == 0){ (*m->areg)(nifc, ip); break; } } runlock(nifc); poperror(); } } } /* added for new v6 mesg types */ static void adddefroute6(Fs *f, uchar *gate, int force) { Route *r; r = v6lookup(f, v6Unspecified, nil); /* * route entries generated by all other means take precedence * over router announcements. */ if (r && !force && strcmp(r->tag, "ra") != 0) return; v6delroute(f, v6Unspecified, v6Unspecified, 1); v6addroute(f, "ra", v6Unspecified, v6Unspecified, gate, 0); } enum { Ngates = 3, }; char* ipifcadd6(Ipifc *ifc, char**argv, int argc) { int plen = 64; char addr[40], preflen[6]; char *params[3]; uchar prefix[IPaddrlen]; Iplifc lifc; lifc.onlink = 1; lifc.autoflag = 1; lifc.validlt = ~0L; lifc.preflt = ~0L; lifc.origint = NOW / 1000; switch(argc) { case 7: lifc.preflt = atoi(argv[6]); /* fall through */ case 6: lifc.validlt = atoi(argv[5]); /* fall through */ case 5: lifc.autoflag = atoi(argv[4]) != 0; /* fall through */ case 4: lifc.onlink = atoi(argv[3]) != 0; /* fall through */ case 3: plen = atoi(argv[2]); /* fall through */ case 2: break; default: return Ebadarg; } if (parseip(prefix, argv[1]) != 6 || lifc.validlt < lifc.preflt || plen < 0 || plen > 64 || islinklocal(prefix)) return Ebadarg; /* issue "add" ctl msg for v6 link-local addr and prefix len */ if(ifc->m->pref2addr == nil) return Ebadarg; (*ifc->m->pref2addr)(prefix, ifc->mac); /* mac → v6 link-local addr */ sprint(addr, "%I", prefix); sprint(preflen, "/%d", plen); params[0] = "add"; params[1] = addr; params[2] = preflen; return ipifcadd(ifc, params, 3, 0, &lifc); }