/* route.c 4.11 82/06/20 */ #include "param.h" #include <sys/systm.h> #include <sys/mbuf.h> #include <sys/protosw.h> #include <sys/socket.h> #include <sys/ioctl.h> #include "../net/in.h" #include "../net/in_systm.h" #include "../net/if.h" #include "../net/af.h" #include "../net/route.h" #include <errno.h> int rttrash; /* routes not in table but not freed */ /* * Packet routing routines. */ rtalloc(ro) register struct route *ro; { register struct rtentry *rt, *rtmin; register u_int hash, (*match)(); struct afhash h; struct sockaddr *dst = &ro->ro_dst; struct sockaddr zeros; /* "Wildcard" destination BRL*/ int af = dst->sa_family; if (ro->ro_rt && ro->ro_rt->rt_ifp) /* XXX */ return; if (af >= AF_MAX) return; top: /* BRL */ (*afswitch[af].af_hash)(dst, &h); rtmin = 0, hash = h.afh_hosthash; for (rt = rthost[hash % RTHASHSIZ]; rt; rt = rt->rt_next) { if (rt->rt_hash != hash) continue; if ((rt->rt_flags & RTF_UP) == 0 || (rt->rt_ifp->if_flags & IFF_UP) == 0) continue; if (bcmp((caddr_t)&rt->rt_dst, (caddr_t)dst, sizeof (*dst))) continue; if (rtmin == 0 || rt->rt_use < rtmin->rt_use) rtmin = rt; } if (rtmin) goto found; hash = h.afh_nethash; match = afswitch[af].af_netmatch; for (rt = rtnet[hash % RTHASHSIZ]; rt; rt = rt->rt_next) { if (rt->rt_hash != hash) continue; if ((rt->rt_flags & RTF_UP) == 0 || (rt->rt_ifp->if_flags & IFF_UP) == 0) continue; if (rt->rt_dst.sa_family != af || !(*match)(&rt->rt_dst, dst)) continue; if (rtmin == 0 || rt->rt_use < rtmin->rt_use) rtmin = rt; } found: ro->ro_rt = rtmin; if (rtmin) rtmin->rt_refcnt++; /* Success! */ else if (dst != &zeros) { /* Look again for "wildcard" route (net 0) BRL */ bzero ((caddr_t) &zeros, sizeof(zeros)); zeros.sa_family = dst->sa_family; dst = &zeros; goto top; } } rtfree(rt) register struct rtentry *rt; { if (rt == 0) panic("freeroute"); rt->rt_refcnt--; if (rt->rt_refcnt == 0 && (rt->rt_flags&RTF_UP) == 0) { rttrash--; MSFREE(rt); } } /* * Carry out a request to change the routing table. Called by * interfaces at boot time to make their ``local routes'' known * and for ioctl's. */ rtrequest(req, entry) int req; register struct rtentry *entry; { register struct rtentry *rt,**rtprev; struct afhash h; u_int af, s, error = 0, hash, (*match)(); struct ifnet *ifp; af = entry->rt_dst.sa_family; if (af >= AF_MAX) return (EAFNOSUPPORT); (*afswitch[af].af_hash)(&entry->rt_dst, &h); if (entry->rt_flags & RTF_HOST) { hash = h.afh_hosthash; rtprev = &rthost[hash % RTHASHSIZ]; } else { hash = h.afh_nethash; rtprev = &rtnet[hash % RTHASHSIZ]; } match = afswitch[af].af_netmatch; s = splimp(); for (; rt = *rtprev; rtprev = &rt->rt_next) { if (rt->rt_hash != hash) continue; if (entry->rt_flags & RTF_HOST) { #define equal(a1, a2) \ (bcmp((caddr_t)(a1), (caddr_t)(a2), sizeof (struct sockaddr)) == 0) if (!equal(&rt->rt_dst, &entry->rt_dst)) continue; } else { if (rt->rt_dst.sa_family != entry->rt_dst.sa_family || (*match)(&rt->rt_dst, &entry->rt_dst) == 0) continue; } if (equal(&rt->rt_gateway, &entry->rt_gateway)) break; } switch (req) { case SIOCDELRT: if (rt == 0) { error = ESRCH; goto bad; } *rtprev = rt->rt_next; if (rt->rt_refcnt > 0) { rt->rt_flags &= ~RTF_UP; rttrash++; rt->rt_next = 0; } else MSFREE(rt); break; case SIOCADDRT: if (rt) { error = EEXIST; goto bad; } ifp = if_ifwithaddr(&entry->rt_gateway); if (ifp == 0) { ifp = if_ifwithnet(&entry->rt_gateway); if (ifp == 0) { error = ENETUNREACH; goto bad; } } MSGET(rt, struct rtentry, 1); if (rt == 0) { error = ENOBUFS; goto bad; } *rtprev = rt; rt->rt_hash = hash; rt->rt_dst = entry->rt_dst; rt->rt_gateway = entry->rt_gateway; rt->rt_flags = RTF_UP | (entry->rt_flags & (RTF_HOST|RTF_GATEWAY)); rt->rt_ifp = ifp; break; } bad: splx(s); return (error); } /* * Set up a routing table entry, normally * for an interface. */ rtinit(dst, gateway, flags) struct sockaddr *dst, *gateway; int flags; { struct rtentry route; struct route ro; bzero((caddr_t)&route, sizeof (route)); route.rt_dst = *dst; route.rt_gateway = *gateway; route.rt_flags = flags; (void) rtrequest(SIOCADDRT, &route); }