ref: 4d4107b38547c7f9f135cc22d3a29fcbad4a8c34
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 *next; /* next address in the hash table */ Iplink *link; /* binding twixt Ipself and Ipifc */ ulong expire; uchar type; /* type of address */ }; 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 void ipifcregisteraddr(Fs*, Ipifc*, Iplifc*, uchar*); static void ipifcregisterproxy(Fs*, Ipifc*, uchar*, int); static char* ipifcremlifc(Ipifc*, Iplifc**); static char Ebound[] = "interface already bound"; static char Eunbound[] = "interface not bound"; enum { unknownv6, /* UGH */ unspecifiedv6, linklocalv6, globalv6, }; static int v6addrtype(uchar *addr) { if(isv4(addr) || ipcmp(addr, IPnoaddr) == 0) return unknownv6; else if(islinklocal(addr) || ipcmp(addr, v6loopback) == 0 || isv6mcast(addr) && (addr[1] & 0xF) <= Link_local_scop) return linklocalv6; else return globalv6; } static int comprefixlen(uchar *a, uchar *b, int n) { int i, c; for(i = 0; i < n; i++){ if((c = a[i] ^ b[i]) == 0) continue; for(i <<= 3; (c & 0x80) == 0; i++) c <<= 1; return i; } return i << 3; } /* * 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 Ebound; } 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; ifc->delay = 40; ifc->speed = 0; if(ifc->m->unbindonclose == 0) ifc->conv->inuse++; /* default router paramters */ ifc->rp = c->p->f->v6p->rp; /* 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 */ static char* ipifcunbind(Ipifc *ifc) { wlock(ifc); if(ifc->m == nil){ wunlock(ifc); return Eunbound; } /* disassociate logical interfaces (before zeroing ifc->arg) */ while(ifc->lifc != nil) ipifcremlifc(ifc, &ifc->lifc); /* disassociate device */ if(ifc->m->unbind != nil){ if(!waserror()){ (*ifc->m->unbind)(ifc); poperror(); } } memset(ifc->dev, 0, sizeof(ifc->dev)); ifc->arg = nil; ifc->reflect = 0; 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->unbindonclose == 0) ifc->conv->inuse--; ifc->m = nil; wunlock(ifc); 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 speed %d delay %d\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, ifc->speed, ifc->delay); rlock(ifc); for(lifc = ifc->lifc; lifc != nil && 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; rlock(ifc); m = 0; for(lifc = ifc->lifc; lifc != nil; lifc = lifc->next){ m += snprint(state+m, n - m, "%-40.40I ->", lifc->local); for(link = lifc->link; link != nil; 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; } static void ipifcadjustburst(Ipifc *ifc) { int burst; burst = ((vlong)ifc->delay * ifc->speed) / 8000; if(burst < ifc->maxtu) burst = ifc->maxtu; ifc->burst = burst; } static void ipifcsetdelay(Ipifc *ifc, int delay) { if(delay < 0) delay = 0; else if(delay > 1000) delay = 1000; ifc->delay = delay; ipifcadjustburst(ifc); } static void ipifcsetspeed(Ipifc *ifc, int speed) { if(speed < 0) speed = 0; ifc->speed = speed; ifc->load = 0; ipifcadjustburst(ifc); } void ipifcoput(Ipifc *ifc, Block *bp, int version, uchar *ip) { if(ifc->speed){ ulong now = MACHP(0)->ticks; int dt = TK2MS(now - ifc->ticks); ifc->ticks = now; ifc->load -= ((vlong)dt * ifc->speed) / 8000; if(ifc->load < 0 || dt < 0 || dt > 1000) ifc->load = 0; else if(ifc->load > ifc->burst){ freeblist(bp); return; } } bp = concatblock(bp); ifc->load += BLEN(bp); ifc->m->bwrite(ifc, bp, version, ip); } /* * 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 != nil && ifc->m->pktin != nil) (*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->m = nil; ifc->reflect = 0; ifc->reassemble = 0; } /* * called after last close of ipifc data or ctl */ static void ipifcclose(Conv *c) { Ipifc *ifc = (Ipifc*)c->ptcl; Medium *m = ifc->m; if(m != nil && m->unbindonclose) ipifcunbind(ifc); } /* * change an interface's mtu */ static char* ipifcsetmtu(Ipifc *ifc, int mtu) { Medium *m = ifc->m; if(m == nil) return Eunbound; if(mtu < m->mintu || mtu > m->maxtu) return Ebadarg; ifc->maxtu = mtu; ipifcadjustburst(ifc); return nil; } /* * add an address to an interface. */ char* ipifcadd(Ipifc *ifc, char **argv, int argc, int tentative, Iplifc *lifcp) { uchar ip[IPaddrlen], mask[IPaddrlen], rem[IPaddrlen]; uchar bcast[IPaddrlen], net[IPaddrlen]; Iplifc *lifc, **l; int i, type, mtu; Fs *f; mtu = 0; 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); /* fall through */ case 4: if (parseipandmask(ip, mask, argv[1], argv[2]) == -1 || parseip(rem, argv[3]) == -1) return Ebadip; maskip(rem, mask, net); break; case 3: if (parseipandmask(ip, mask, argv[1], argv[2]) == -1) return Ebadip; 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; } /* check for point-to-point interface */ if(ipcmp(ip, v6loopback) != 0) /* skip v6 loopback, it's a special address */ if(ipcmp(mask, IPallbits) == 0) type |= Rptpt; if(isv4(ip) || ipcmp(ip, IPnoaddr) == 0){ type |= Rv4; tentative = 0; } wlock(ifc); if(ifc->m == nil){ wunlock(ifc); return Eunbound; } f = ifc->conv->p->f; if(waserror()){ wunlock(ifc); return up->errstr; } if(mtu > 0) ipifcsetmtu(ifc, mtu); /* ignore if this is already a local address for this ifc */ if((lifc = iplocalonifc(ifc, ip)) != nil){ if(lifcp != nil) { if(!lifc->onlink && lifcp->onlink){ lifc->onlink = 1; addroute(f, lifc->remote, lifc->mask, ip, IPallbits, lifc->remote, lifc->type, ifc, tifc); if(v6addrtype(ip) != linklocalv6) addroute(f, lifc->remote, lifc->mask, ip, IPnoaddr, lifc->remote, lifc->type, ifc, tifc); } lifc->autoflag = lifcp->autoflag; lifc->validlt = lifcp->validlt; lifc->preflt = lifcp->preflt; lifc->origint = lifcp->origint; } if(lifc->tentative != tentative){ lifc->tentative = tentative; goto done; } wunlock(ifc); poperror(); return nil; } /* 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->type = type; lifc->tentative = tentative; if(lifcp != nil) { 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 = ~0UL; lifc->origint = NOW / 1000; } lifc->next = nil; for(l = &ifc->lifc; *l != nil; l = &(*l)->next) ; *l = lifc; /* add route for this logical interface */ if(lifc->onlink){ addroute(f, rem, mask, ip, IPallbits, rem, type, ifc, tifc); if(v6addrtype(ip) != linklocalv6) addroute(f, rem, mask, ip, IPnoaddr, rem, type, ifc, tifc); } addselfcache(f, ifc, lifc, ip, Runi); /* register proxy */ if(type & Rptpt){ if(type & Rproxy) ipifcregisterproxy(f, ifc, rem, 1); goto done; } if(type & Rv4) { /* 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 */ addroute(f, v6allnodesN, v6allnodesNmask, ip, IPallbits, v6allnodesN, Rmulti, ifc, tifc); } /* add all nodes multicast address */ addselfcache(f, ifc, lifc, v6allnodesL, Rmulti); /* add route for all nodes multicast */ addroute(f, v6allnodesL, v6allnodesLmask, ip, IPallbits, v6allnodesL, Rmulti, ifc, tifc); /* add solicited-node multicast address */ ipv62smcast(bcast, ip); addselfcache(f, ifc, lifc, bcast, Rmulti); } done: ipifcregisteraddr(f, ifc, lifc, ip); wunlock(ifc); poperror(); return nil; } /* * remove a logical interface from an ifc * called with ifc wlock'd */ static char* ipifcremlifc(Ipifc *ifc, Iplifc **l) { Iplifc *lifc = *l; Fs *f = ifc->conv->p->f; if(lifc == nil) return "address not on this interface"; *l = lifc->next; /* disassociate any addresses */ while(lifc->link != nil) remselfcache(f, ifc, lifc, lifc->link->self->a); /* remove the route for this logical interface */ if(lifc->onlink){ remroute(f, lifc->remote, lifc->mask, lifc->local, IPallbits, lifc->remote, lifc->type, ifc, tifc); if(v6addrtype(lifc->local) != linklocalv6) remroute(f, lifc->remote, lifc->mask, lifc->local, IPnoaddr, lifc->remote, lifc->type, ifc, tifc); } /* unregister proxy */ if(lifc->type & Rptpt){ if(lifc->type & Rproxy) ipifcregisterproxy(f, ifc, lifc->remote, 0); goto done; } /* remove route for all nodes multicast */ if((lifc->type & Rv4) == 0){ if(ipcmp(lifc->local, v6loopback) == 0) remroute(f, v6allnodesN, v6allnodesNmask, lifc->local, IPallbits, v6allnodesN, Rmulti, ifc, tifc); remroute(f, v6allnodesL, v6allnodesLmask, lifc->local, IPallbits, v6allnodesL, Rmulti, ifc, tifc); } done: free(lifc); return nil; } /* * remove an address from an interface. */ char* ipifcrem(Ipifc *ifc, char **argv, int argc) { uchar ip[IPaddrlen], mask[IPaddrlen], rem[IPaddrlen]; Iplifc *lifc, **l; char *err; if(argc < 3) return Ebadarg; if(parseipandmask(ip, mask, argv[1], argv[2]) == -1) return Ebadip; 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); l = &ifc->lifc; for(lifc = ifc->lifc; lifc != nil; lifc = lifc->next) { if(ipcmp(ip, lifc->local) == 0 && ipcmp(mask, lifc->mask) == 0 && ipcmp(rem, lifc->remote) == 0) break; l = &lifc->next; } err = ipifcremlifc(ifc, l); wunlock(ifc); return err; } /* * 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) { Ipifc *ifc = (Ipifc*)c->ptcl; char *err; wlock(ifc); while(ifc->lifc != nil) ipifcremlifc(ifc, &ifc->lifc); wunlock(ifc); err = ipifcadd(ifc, argv, argc, 0, nil); if(err != nil) return err; Fsconnected(c, nil); return nil; } char* ipifcra6(Ipifc *ifc, char **argv, int argc) { int i, argsleft; uchar sendra, recvra; Routerparams rp; i = 1; argsleft = argc - 1; if((argsleft % 2) != 0) return Ebadarg; sendra = ifc->sendra6; recvra = ifc->recvra6; rp = ifc->rp; while (argsleft > 1) { if(strcmp(argv[i], "recvra") == 0) recvra = atoi(argv[i+1]) != 0; else if(strcmp(argv[i], "sendra") == 0) sendra = atoi(argv[i+1]) != 0; else if(strcmp(argv[i], "mflag") == 0) rp.mflag = atoi(argv[i+1]) != 0; else if(strcmp(argv[i], "oflag") == 0) rp.oflag = atoi(argv[i+1]) != 0; else if(strcmp(argv[i], "maxraint") == 0) rp.maxraint = atoi(argv[i+1]); else if(strcmp(argv[i], "minraint") == 0) rp.minraint = atoi(argv[i+1]); else if(strcmp(argv[i], "linkmtu") == 0) rp.linkmtu = atoi(argv[i+1]); else if(strcmp(argv[i], "reachtime") == 0) rp.reachtime = atoi(argv[i+1]); else if(strcmp(argv[i], "rxmitra") == 0) rp.rxmitra = atoi(argv[i+1]); else if(strcmp(argv[i], "ttl") == 0) rp.ttl = atoi(argv[i+1]); else if(strcmp(argv[i], "routerlt") == 0) rp.routerlt = atoi(argv[i+1]); else return Ebadarg; argsleft -= 2; i += 2; } /* consistency check */ if(rp.maxraint < rp.minraint) return Ebadarg; ifc->rp = rp; ifc->sendra6 = sendra; ifc->recvra6 = recvra; return nil; } /* * non-standard control messages. */ static char* ipifcctl(Conv* c, char **argv, int argc) { Ipifc *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], "mtu") == 0) return ipifcsetmtu(ifc, argc>1? strtoul(argv[1], 0, 0): 0); else if(strcmp(argv[0], "speed") == 0){ ipifcsetspeed(ifc, argc>1? atoi(argv[1]): 0); return nil; } else if(strcmp(argv[0], "delay") == 0){ ipifcsetdelay(ifc, argc>1? atoi(argv[1]): 0); return nil; } else if(strcmp(argv[0], "iprouting") == 0){ iprouting(c->p->f, argc>1? atoi(argv[1]): 1); return nil; } else if(strcmp(argv[0], "reflect") == 0){ ifc->reflect = argc>1? atoi(argv[1]): 1; return nil; } else if(strcmp(argv[0], "reassemble") == 0){ ifc->reassemble = argc>1? atoi(argv[1]): 1; return nil; } else if(strcmp(argv[0], "add6") == 0) return ipifcadd6(ifc, argv, argc); else if(strcmp(argv[0], "remove6") == 0) return ipifcremove6(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 */ static void addselfcache(Fs *f, Ipifc *ifc, Iplifc *lifc, uchar *a, int type) { Iplink *lp; Ipself *p; int h; type |= (lifc->type & Rv4); 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 != nil; p = p->next) if(ipcmp(a, p->a) == 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 != nil; 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 */ addroute(f, a, IPallbits, lifc->local, ((type & (Rbcast|Rmulti)) != 0 || v6addrtype(a) == linklocalv6) ? IPallbits : IPnoaddr, a, type, ifc, tifc); if((type & Rmulti) && ifc->m->addmulti != nil) (*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 != nil; np = *l){ if((long)(now - np->expire) >= 0){ *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 != nil; np = *l){ if((long)(now - np->expire) >= 0){ *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. */ 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 != nil; 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 != nil; 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 != nil; link = *l_self){ if(link == *l_lifc) break; l_self = &link->selflink; } if(link == nil) panic("remselfcache"); if(--(link->ref) != 0) goto out; /* remove from routing table */ remroute(f, a, IPallbits, lifc->local, ((p->type & (Rbcast|Rmulti)) != 0 || v6addrtype(a) == linklocalv6) ? IPallbits : IPnoaddr, a, p->type, ifc, tifc); if((p->type & Rmulti) && ifc->m->remmulti != nil){ 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; /* if null address, forget */ if(ipcmp(a, v4prefix) == 0 || ipcmp(a, IPnoaddr) == 0) f->self->acceptall = 0; /* no more links, remove from hash and free */ *l = p->next; ipselffree(p); out: qunlock(f->self); } 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; 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 != nil; link = link->selflink) nifc++; routetype(p->type, state); m += snprint(cp + m, n - m, "%-44.44I %2.2d %4.4s\n", p->a, nifc, state); if(off > 0){ off -= m; m = 0; } } } return m; } /* * returns * 0 - no match * Runi * Rbcast * Rmulti */ int ipforme(Fs *f, uchar *addr) { Ipself *p; for(p = f->self->hash[hashipa(addr)]; p != nil; p = p->next) if(ipcmp(addr, p->a) == 0) return p->type & (Runi|Rbcast|Rmulti); /* 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 *local, uchar *remote, int type) { uchar gnet[IPaddrlen]; int spec, xspec; Ipifc *ifc, *x; Iplifc *lifc; Conv **cp; x = nil; xspec = 0; for(cp = f->ipifc->conv; *cp != nil; cp++){ ifc = (Ipifc*)(*cp)->ptcl; rlock(ifc); for(lifc = ifc->lifc; lifc != nil; lifc = lifc->next){ if(type & Runi){ if(ipcmp(remote, lifc->local) == 0){ Found: runlock(ifc); return ifc; } } else if(type & (Rbcast|Rmulti)) { if(ipcmp(local, lifc->local) == 0) goto Found; } maskip(remote, lifc->mask, gnet); if(ipcmp(gnet, lifc->net) == 0){ spec = comprefixlen(remote, lifc->local, IPaddrlen); if(spec > xspec){ x = ifc; xspec = spec; } } } runlock(ifc); } return x; } Ipifc* findipifcstr(Fs *f, char *s) { uchar ip[IPaddrlen]; Conv *c; char *p; long x; x = strtol(s, &p, 10); if(p > s && *p == '\0'){ if(x < 0) return nil; if(x < f->ipifc->nc && (c = f->ipifc->conv[x]) != nil && ipifcinuse(c)) return (Ipifc*)c->ptcl; } if(parseip(ip, s) != -1) return findipifc(f, ip, ip, Runi); return nil; } /* * find "best" (global > link local > unspecified) * local address; address must be current. */ static void findprimaryipv6(Fs *f, uchar *local) { ulong now = NOW/1000; int atype, atypel; Iplifc *lifc; Ipifc *ifc; Conv **cp; ipmove(local, v6Unspecified); atype = unspecifiedv6; for(cp = f->ipifc->conv; *cp != nil; cp++){ ifc = (Ipifc*)(*cp)->ptcl; rlock(ifc); for(lifc = ifc->lifc; lifc != nil; lifc = lifc->next){ atypel = v6addrtype(lifc->local); if(atypel > atype) if(lifc->preflt == ~0UL || lifc->preflt >= now-lifc->origint) { ipmove(local, lifc->local); atype = atypel; if(atype == globalv6){ runlock(ifc); return; } } } runlock(ifc); } } /* * returns first v4 address configured */ static void findprimaryipv4(Fs *f, uchar *local) { Iplifc *lifc; Ipifc *ifc; Conv **cp; /* find first ifc local address */ for(cp = f->ipifc->conv; *cp != nil; cp++){ ifc = (Ipifc*)(*cp)->ptcl; rlock(ifc); for(lifc = ifc->lifc; lifc != nil; lifc = lifc->next){ if((lifc->type & Rv4) != 0){ ipmove(local, lifc->local); runlock(ifc); return; } } runlock(ifc); } ipmove(local, IPnoaddr); } /* * ipv4local, ipv6local: * return a local address associated with an interface close to remote. * prefixlen is the number of leading bits in the local address that * have to match an interface address to be considered. this is used * by source specific routes to filter on the source address. * return non-zero on success or zero when no address was found. * * for ipv4local, all addresses are 4 byte format. */ int ipv4local(Ipifc *ifc, uchar *local, int prefixlen, uchar *remote) { Iplifc *lifc; int a, b; b = -1; for(lifc = ifc->lifc; lifc != nil; lifc = lifc->next){ if((lifc->type & Rv4) == 0 || ipcmp(lifc->local, IPnoaddr) == 0) continue; if(prefixlen && comprefixlen(lifc->local+IPv4off, local, IPv4addrlen) < prefixlen) continue; a = comprefixlen(lifc->local+IPv4off, remote, IPv4addrlen); if(a > b){ b = a; memmove(local, lifc->local+IPv4off, IPv4addrlen); } } return b >= 0; } int ipv6local(Ipifc *ifc, uchar *local, int prefixlen, uchar *remote) { struct { int atype; int deprecated; int comprefixlen; } a, b; int atype; ulong now; Iplifc *lifc; if(isv4(remote)){ memmove(local, v4prefix, IPv4off); if((prefixlen -= IPv4off*8) < 0) prefixlen = 0; return ipv4local(ifc, local+IPv4off, prefixlen, remote+IPv4off); } atype = v6addrtype(remote); b.atype = unknownv6; b.deprecated = 1; b.comprefixlen = 0; now = NOW/1000; for(lifc = ifc->lifc; lifc != nil; lifc = lifc->next){ if(lifc->tentative) continue; if(prefixlen && comprefixlen(lifc->local, local, IPaddrlen) < prefixlen) continue; a.atype = v6addrtype(lifc->local); a.deprecated = lifc->preflt != ~0UL && lifc->preflt < now-lifc->origint; a.comprefixlen = comprefixlen(lifc->local, remote, IPaddrlen); /* prefer appropriate scope */ if(a.atype != b.atype){ if(a.atype > b.atype && b.atype < atype || a.atype < b.atype && b.atype > atype) goto Good; continue; } /* prefer non-deprecated addresses */ if(a.deprecated != b.deprecated){ if(b.deprecated) goto Good; continue; } /* prefer longer common prefix */ if(a.comprefixlen != b.comprefixlen){ if(a.comprefixlen > b.comprefixlen) goto Good; continue; } continue; Good: b = a; ipmove(local, lifc->local); } return b.atype >= atype; } /* * find the local address for a remote destination */ void findlocalip(Fs *f, uchar *local, uchar *remote) { if(isv4(remote)) { memmove(local, v4prefix, IPv4off); if(v4source(f, remote+IPv4off, local+IPv4off) == nil) findprimaryipv4(f, local); } else { if(v6source(f, remote, local) == nil) findprimaryipv6(f, local); } } /* * see if this address is bound to the interface */ Iplifc* iplocalonifc(Ipifc *ifc, uchar *ip) { Iplifc *lifc; for(lifc = ifc->lifc; lifc != nil; lifc = lifc->next) if(ipcmp(ip, lifc->local) == 0) return lifc; return nil; } Iplifc* ipremoteonifc(Ipifc *ifc, uchar *ip) { uchar net[IPaddrlen]; Iplifc *lifc; for(lifc = ifc->lifc; lifc != nil; lifc = lifc->next){ maskip(ip, lifc->mask, net); if(ipcmp(net, lifc->remote) == 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; /* see if this is a direct connected pt to pt address */ r = v6lookup(f, ip, ip, nil); if(r == nil || (r->type & (Rifc|Rproxy)) != (Rifc|Rproxy)) return 0; return ipremoteonifc(ifc, ip) != nil; } /* * 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; } /* * add a multicast address to an interface. */ void ipifcaddmulti(Conv *c, uchar *ma, uchar *ia) { Ipmulti *multi, **l; Iplifc *lifc; Ipifc *ifc; Fs *f; if(isv4(ma) != isv4(ia)) error("incompatible multicast/interface ip address"); for(l = &c->multi; *l != nil; l = &(*l)->next) if(ipcmp(ma, (*l)->ma) == 0 && ipcmp(ia, (*l)->ia) == 0) return; /* it's already there */ f = c->p->f; if((ifc = findipifc(f, ia, ma, Rmulti)) != nil){ rlock(ifc); if(waserror()){ runlock(ifc); nexterror(); } if((lifc = iplocalonifc(ifc, ia)) != nil) addselfcache(f, ifc, lifc, ma, Rmulti); runlock(ifc); poperror(); } multi = smalloc(sizeof(*multi)); ipmove(multi->ma, ma); ipmove(multi->ia, ia); multi->next = nil; *l = multi; } /* * remove a multicast address from an interface. */ void ipifcremmulti(Conv *c, uchar *ma, uchar *ia) { Ipmulti *multi, **l; Iplifc *lifc; Ipifc *ifc; Fs *f; for(l = &c->multi; *l != nil; 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; multi->next = nil; f = c->p->f; if((ifc = findipifc(f, ia, ma, Rmulti)) != nil){ rlock(ifc); if(!waserror()){ if((lifc = iplocalonifc(ifc, ia)) != nil) remselfcache(f, ifc, lifc, ma); poperror(); } runlock(ifc); } free(multi); } /* register the address on this network for address resolution */ static void ipifcregisteraddr(Fs *f, Ipifc *ifc, Iplifc *lifc, uchar *ip) { if(waserror()){ print("ipifcregisteraddr %s %I %I: %s\n", ifc->dev, lifc->local, ip, up->errstr); return; } if(ifc->m != nil && ifc->m->areg != nil) (*ifc->m->areg)(f, ifc, lifc, ip); poperror(); } static void ipifcregisterproxy(Fs *f, Ipifc *ifc, uchar *ip, int add) { uchar a[IPaddrlen]; Iplifc *lifc; Ipifc *nifc; Conv **cp; /* register the address on any interface that will proxy for the ip */ for(cp = f->ipifc->conv; *cp != nil; cp++){ nifc = (Ipifc*)(*cp)->ptcl; if(nifc == ifc || !canrlock(nifc)) continue; if(nifc->m == nil || (lifc = ipremoteonifc(nifc, ip)) == nil || (lifc->type & Rptpt) != 0 || waserror()){ runlock(nifc); continue; } if((lifc->type & Rv4) == 0){ /* add solicited-node multicast addr */ ipv62smcast(a, ip); if(add) addselfcache(f, nifc, lifc, a, Rmulti); else remselfcache(f, nifc, lifc, a); } if(add) ipifcregisteraddr(f, nifc, lifc, ip); runlock(nifc); poperror(); } } char* ipifcadd6(Ipifc *ifc, char **argv, int argc) { int plen = 64; char addr[40], preflen[6]; char *params[3]; uchar prefix[IPaddrlen]; Iplifc lifc; Medium *m; lifc.onlink = 1; lifc.autoflag = 1; lifc.validlt = lifc.preflt = ~0UL; lifc.origint = NOW / 1000; switch(argc) { case 7: lifc.preflt = strtoul(argv[6], 0, 10); /* fall through */ case 6: lifc.validlt = strtoul(argv[5], 0, 10); /* 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 */ m = ifc->m; if(m == nil || m->pref2addr == nil) return Eunbound; (*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); } char* ipifcremove6(Ipifc *ifc, char**, int argc) { Iplifc *lifc, **l; ulong now; if(argc != 1) return Ebadarg; wlock(ifc); now = NOW/1000; for(l = &ifc->lifc; (lifc = *l) != nil;) { if((lifc->type & Rv4) == 0) if(lifc->validlt != ~0UL && lifc->validlt < now-lifc->origint) if(ipifcremlifc(ifc, l) == nil) continue; l = &lifc->next; } wunlock(ifc); return nil; }