diff options
Diffstat (limited to 'usr.sbin/routed/tables.c')
| -rw-r--r-- | usr.sbin/routed/tables.c | 428 |
1 files changed, 428 insertions, 0 deletions
diff --git a/usr.sbin/routed/tables.c b/usr.sbin/routed/tables.c new file mode 100644 index 0000000..ac837f8 --- /dev/null +++ b/usr.sbin/routed/tables.c @@ -0,0 +1,428 @@ +/* + * Copyright (c) 1983, 1988, 1993 + * The Regents of the University of California. All rights reserved. + * + * Redistribution and use in source and binary forms, with or without + * modification, are permitted provided that the following conditions + * are met: + * 1. Redistributions of source code must retain the above copyright + * notice, this list of conditions and the following disclaimer. + * 2. Redistributions in binary form must reproduce the above copyright + * notice, this list of conditions and the following disclaimer in the + * documentation and/or other materials provided with the distribution. + * 3. All advertising materials mentioning features or use of this software + * must display the following acknowledgement: + * This product includes software developed by the University of + * California, Berkeley and its contributors. + * 4. Neither the name of the University nor the names of its contributors + * may be used to endorse or promote products derived from this software + * without specific prior written permission. + * + * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND + * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE + * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE + * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE + * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL + * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS + * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) + * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT + * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY + * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF + * SUCH DAMAGE. + */ + +#ifndef lint +static char sccsid[] = "@(#)tables.c 8.1 (Berkeley) 6/5/93"; +#endif /* not lint */ + +/* + * Routing Table Management Daemon + */ +#include "defs.h" +#include <sys/ioctl.h> +#include <errno.h> +#include <sys/syslog.h> + +#ifndef DEBUG +#define DEBUG 0 +#endif + +#ifdef RTM_ADD +#define FIXLEN(s) {if ((s)->sa_len == 0) (s)->sa_len = sizeof *(s);} +#else +#define FIXLEN(s) { } +#endif + +int install = !DEBUG; /* if 1 call kernel */ + +/* + * Lookup dst in the tables for an exact match. + */ +struct rt_entry * +rtlookup(dst) + struct sockaddr *dst; +{ + register struct rt_entry *rt; + register struct rthash *rh; + register u_int hash; + struct afhash h; + int doinghost = 1; + + if (dst->sa_family >= af_max) + return (0); + (*afswitch[dst->sa_family].af_hash)(dst, &h); + hash = h.afh_hosthash; + rh = &hosthash[hash & ROUTEHASHMASK]; +again: + for (rt = rh->rt_forw; rt != (struct rt_entry *)rh; rt = rt->rt_forw) { + if (rt->rt_hash != hash) + continue; + if (equal(&rt->rt_dst, dst)) + return (rt); + } + if (doinghost) { + doinghost = 0; + hash = h.afh_nethash; + rh = &nethash[hash & ROUTEHASHMASK]; + goto again; + } + return (0); +} + +struct sockaddr wildcard; /* zero valued cookie for wildcard searches */ + +/* + * Find a route to dst as the kernel would. + */ +struct rt_entry * +rtfind(dst) + struct sockaddr *dst; +{ + register struct rt_entry *rt; + register struct rthash *rh; + register u_int hash; + struct afhash h; + int af = dst->sa_family; + int doinghost = 1, (*match)(); + + if (af >= af_max) + return (0); + (*afswitch[af].af_hash)(dst, &h); + hash = h.afh_hosthash; + rh = &hosthash[hash & ROUTEHASHMASK]; + +again: + for (rt = rh->rt_forw; rt != (struct rt_entry *)rh; rt = rt->rt_forw) { + if (rt->rt_hash != hash) + continue; + if (doinghost) { + if (equal(&rt->rt_dst, dst)) + return (rt); + } else { + if (rt->rt_dst.sa_family == af && + (*match)(&rt->rt_dst, dst)) + return (rt); + } + } + if (doinghost) { + doinghost = 0; + hash = h.afh_nethash; + rh = &nethash[hash & ROUTEHASHMASK]; + match = afswitch[af].af_netmatch; + goto again; + } +#ifdef notyet + /* + * Check for wildcard gateway, by convention network 0. + */ + if (dst != &wildcard) { + dst = &wildcard, hash = 0; + goto again; + } +#endif + return (0); +} + +rtadd(dst, gate, metric, state) + struct sockaddr *dst, *gate; + int metric, state; +{ + struct afhash h; + register struct rt_entry *rt; + struct rthash *rh; + int af = dst->sa_family, flags; + u_int hash; + + if (af >= af_max) + return; + (*afswitch[af].af_hash)(dst, &h); + flags = (*afswitch[af].af_rtflags)(dst); + /* + * Subnet flag isn't visible to kernel, move to state. XXX + */ + FIXLEN(dst); + FIXLEN(gate); + if (flags & RTF_SUBNET) { + state |= RTS_SUBNET; + flags &= ~RTF_SUBNET; + } + if (flags & RTF_HOST) { + hash = h.afh_hosthash; + rh = &hosthash[hash & ROUTEHASHMASK]; + } else { + hash = h.afh_nethash; + rh = &nethash[hash & ROUTEHASHMASK]; + } + rt = (struct rt_entry *)malloc(sizeof (*rt)); + if (rt == 0) + return; + rt->rt_hash = hash; + rt->rt_dst = *dst; + rt->rt_router = *gate; + rt->rt_timer = 0; + rt->rt_flags = RTF_UP | flags; + rt->rt_state = state | RTS_CHANGED; + rt->rt_ifp = if_ifwithdstaddr(&rt->rt_dst); + if (rt->rt_ifp == 0) + rt->rt_ifp = if_ifwithnet(&rt->rt_router); + if ((state & RTS_INTERFACE) == 0) + rt->rt_flags |= RTF_GATEWAY; + rt->rt_metric = metric; + insque(rt, rh); + TRACE_ACTION("ADD", rt); + /* + * If the ioctl fails because the gateway is unreachable + * from this host, discard the entry. This should only + * occur because of an incorrect entry in /etc/gateways. + */ + if ((rt->rt_state & (RTS_INTERNAL | RTS_EXTERNAL)) == 0 && + rtioctl(ADD, &rt->rt_rt) < 0) { + if (errno != EEXIST && gate->sa_family < af_max) + syslog(LOG_ERR, + "adding route to net/host %s through gateway %s: %m\n", + (*afswitch[dst->sa_family].af_format)(dst), + (*afswitch[gate->sa_family].af_format)(gate)); + perror("ADD ROUTE"); + if (errno == ENETUNREACH) { + TRACE_ACTION("DELETE", rt); + remque(rt); + free((char *)rt); + } + } +} + +rtchange(rt, gate, metric) + struct rt_entry *rt; + struct sockaddr *gate; + short metric; +{ + int add = 0, delete = 0, newgateway = 0; + struct rtuentry oldroute; + + FIXLEN(gate); + FIXLEN(&(rt->rt_router)); + FIXLEN(&(rt->rt_dst)); + if (!equal(&rt->rt_router, gate)) { + newgateway++; + TRACE_ACTION("CHANGE FROM ", rt); + } else if (metric != rt->rt_metric) + TRACE_NEWMETRIC(rt, metric); + if ((rt->rt_state & RTS_INTERNAL) == 0) { + /* + * If changing to different router, we need to add + * new route and delete old one if in the kernel. + * If the router is the same, we need to delete + * the route if has become unreachable, or re-add + * it if it had been unreachable. + */ + if (newgateway) { + add++; + if (rt->rt_metric != HOPCNT_INFINITY) + delete++; + } else if (metric == HOPCNT_INFINITY) + delete++; + else if (rt->rt_metric == HOPCNT_INFINITY) + add++; + } + if (delete) + oldroute = rt->rt_rt; + if ((rt->rt_state & RTS_INTERFACE) && delete) { + rt->rt_state &= ~RTS_INTERFACE; + rt->rt_flags |= RTF_GATEWAY; + if (metric > rt->rt_metric && delete) + syslog(LOG_ERR, "%s route to interface %s (timed out)", + add? "changing" : "deleting", + rt->rt_ifp ? rt->rt_ifp->int_name : "?"); + } + if (add) { + rt->rt_router = *gate; + rt->rt_ifp = if_ifwithdstaddr(&rt->rt_router); + if (rt->rt_ifp == 0) + rt->rt_ifp = if_ifwithnet(&rt->rt_router); + } + rt->rt_metric = metric; + rt->rt_state |= RTS_CHANGED; + if (newgateway) + TRACE_ACTION("CHANGE TO ", rt); +#ifndef RTM_ADD + if (add && rtioctl(ADD, &rt->rt_rt) < 0) + perror("ADD ROUTE"); + if (delete && rtioctl(DELETE, &oldroute) < 0) + perror("DELETE ROUTE"); +#else + if (delete && !add) { + if (rtioctl(DELETE, &oldroute) < 0) + perror("DELETE ROUTE"); + } else if (!delete && add) { + if (rtioctl(ADD, &rt->rt_rt) < 0) + perror("ADD ROUTE"); + } else if (delete && add) { + if (rtioctl(CHANGE, &rt->rt_rt) < 0) + perror("CHANGE ROUTE"); + } +#endif +} + +rtdelete(rt) + struct rt_entry *rt; +{ + + TRACE_ACTION("DELETE", rt); + FIXLEN(&(rt->rt_router)); + FIXLEN(&(rt->rt_dst)); + if (rt->rt_metric < HOPCNT_INFINITY) { + if ((rt->rt_state & (RTS_INTERFACE|RTS_INTERNAL)) == RTS_INTERFACE) + syslog(LOG_ERR, + "deleting route to interface %s? (timed out?)", + rt->rt_ifp->int_name); + if ((rt->rt_state & (RTS_INTERNAL | RTS_EXTERNAL)) == 0 && + rtioctl(DELETE, &rt->rt_rt) < 0) + perror("rtdelete"); + } + remque(rt); + free((char *)rt); +} + +rtdeleteall(sig) + int sig; +{ + register struct rthash *rh; + register struct rt_entry *rt; + struct rthash *base = hosthash; + int doinghost = 1; + +again: + for (rh = base; rh < &base[ROUTEHASHSIZ]; rh++) { + rt = rh->rt_forw; + for (; rt != (struct rt_entry *)rh; rt = rt->rt_forw) { + if (rt->rt_state & RTS_INTERFACE || + rt->rt_metric >= HOPCNT_INFINITY) + continue; + TRACE_ACTION("DELETE", rt); + if ((rt->rt_state & (RTS_INTERNAL|RTS_EXTERNAL)) == 0 && + rtioctl(DELETE, &rt->rt_rt) < 0) + perror("rtdeleteall"); + } + } + if (doinghost) { + doinghost = 0; + base = nethash; + goto again; + } + exit(sig); +} + +/* + * If we have an interface to the wide, wide world, + * add an entry for an Internet default route (wildcard) to the internal + * tables and advertise it. This route is not added to the kernel routes, + * but this entry prevents us from listening to other people's defaults + * and installing them in the kernel here. + */ +rtdefault() +{ + extern struct sockaddr inet_default; + + rtadd(&inet_default, &inet_default, 1, + RTS_CHANGED | RTS_PASSIVE | RTS_INTERNAL); +} + +rtinit() +{ + register struct rthash *rh; + + for (rh = nethash; rh < &nethash[ROUTEHASHSIZ]; rh++) + rh->rt_forw = rh->rt_back = (struct rt_entry *)rh; + for (rh = hosthash; rh < &hosthash[ROUTEHASHSIZ]; rh++) + rh->rt_forw = rh->rt_back = (struct rt_entry *)rh; +} + +rtioctl(action, ort) + int action; + struct rtuentry *ort; +{ +#ifndef RTM_ADD + if (install == 0) + return (errno = 0); + ort->rtu_rtflags = ort->rtu_flags; + switch (action) { + + case ADD: + return (ioctl(s, SIOCADDRT, (char *)ort)); + + case DELETE: + return (ioctl(s, SIOCDELRT, (char *)ort)); + + default: + return (-1); + } +#else /* RTM_ADD */ + struct { + struct rt_msghdr w_rtm; + struct sockaddr_in w_dst; + struct sockaddr w_gate; + struct sockaddr_in w_netmask; + } w; +#define rtm w.w_rtm + + bzero((char *)&w, sizeof(w)); + rtm.rtm_msglen = sizeof(w); + rtm.rtm_version = RTM_VERSION; + rtm.rtm_type = (action == ADD ? RTM_ADD : + (action == DELETE ? RTM_DELETE : RTM_CHANGE)); +#undef rt_dst + rtm.rtm_flags = ort->rtu_flags; + rtm.rtm_seq = ++seqno; + rtm.rtm_addrs = RTA_DST|RTA_GATEWAY; + bcopy((char *)&ort->rtu_dst, (char *)&w.w_dst, sizeof(w.w_dst)); + bcopy((char *)&ort->rtu_router, (char *)&w.w_gate, sizeof(w.w_gate)); + w.w_dst.sin_family = AF_INET; + w.w_dst.sin_len = sizeof(w.w_dst); + w.w_gate.sa_family = AF_INET; + w.w_gate.sa_len = sizeof(w.w_gate); + if (rtm.rtm_flags & RTF_HOST) { + rtm.rtm_msglen -= sizeof(w.w_netmask); + } else { + register char *cp; + int len; + + rtm.rtm_addrs |= RTA_NETMASK; + w.w_netmask.sin_addr.s_addr = + inet_maskof(w.w_dst.sin_addr.s_addr); + for (cp = (char *)(1 + &w.w_netmask.sin_addr); + --cp > (char *) &w.w_netmask; ) + if (*cp) + break; + len = cp - (char *)&w.w_netmask; + if (len) { + len++; + w.w_netmask.sin_len = len; + len = 1 + ((len - 1) | (sizeof(long) - 1)); + } else + len = sizeof(long); + rtm.rtm_msglen -= (sizeof(w.w_netmask) - len); + } + errno = 0; + return (install ? write(r, (char *)&w, rtm.rtm_msglen) : (errno = 0)); +#endif /* RTM_ADD */ +} |
