Net2/usr/src/sbin/routed/startup.c
/*
* Copyright (c) 1983, 1988 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[] = "@(#)startup.c 5.19 (Berkeley) 2/28/91";
#endif /* not lint */
/*
* Routing Table Management Daemon
*/
#include "defs.h"
#include <sys/ioctl.h>
#include <net/if.h>
#include <syslog.h>
#include <stdlib.h>
#include "pathnames.h"
struct interface *ifnet;
struct interface **ifnext = &ifnet;
int lookforinterfaces = 1;
int externalinterfaces = 0; /* # of remote and local interfaces */
int foundloopback; /* valid flag for loopaddr */
struct sockaddr loopaddr; /* our address on loopback */
/*
* Find the network interfaces which have configured themselves.
* If the interface is present but not yet up (for example an
* ARPANET IMP), set the lookforinterfaces flag so we'll
* come back later and look again.
*/
ifinit()
{
struct interface ifs, *ifp;
int s;
char buf[BUFSIZ], *cp, *cplim;
struct ifconf ifc;
struct ifreq ifreq, *ifr;
struct sockaddr_in *sin;
u_long i;
if ((s = socket(AF_INET, SOCK_DGRAM, 0)) < 0) {
syslog(LOG_ERR, "socket: %m");
close(s);
return;
}
ifc.ifc_len = sizeof (buf);
ifc.ifc_buf = buf;
if (ioctl(s, SIOCGIFCONF, (char *)&ifc) < 0) {
syslog(LOG_ERR, "ioctl (get interface configuration)");
close(s);
return;
}
ifr = ifc.ifc_req;
lookforinterfaces = 0;
#ifdef RTM_ADD
#define max(a, b) (a > b ? a : b)
#define size(p) max((p).sa_len, sizeof(p))
#else
#define size(p) (sizeof (p))
#endif
cplim = buf + ifc.ifc_len; /*skip over if's with big ifr_addr's */
for (cp = buf; cp < cplim;
cp += sizeof (ifr->ifr_name) + size(ifr->ifr_addr)) {
ifr = (struct ifreq *)cp;
bzero((char *)&ifs, sizeof(ifs));
ifs.int_addr = ifr->ifr_addr;
ifreq = *ifr;
if (ioctl(s, SIOCGIFFLAGS, (char *)&ifreq) < 0) {
syslog(LOG_ERR, "%s: ioctl (get interface flags)",
ifr->ifr_name);
continue;
}
ifs.int_flags = ifreq.ifr_flags | IFF_INTERFACE;
if ((ifs.int_flags & IFF_UP) == 0 ||
ifr->ifr_addr.sa_family == AF_UNSPEC) {
lookforinterfaces = 1;
continue;
}
/* argh, this'll have to change sometime */
if (ifs.int_addr.sa_family != AF_INET)
continue;
if (ifs.int_flags & IFF_POINTOPOINT) {
if (ioctl(s, SIOCGIFDSTADDR, (char *)&ifreq) < 0) {
syslog(LOG_ERR, "%s: ioctl (get dstaddr)",
ifr->ifr_name);
continue;
}
if (ifr->ifr_addr.sa_family == AF_UNSPEC) {
lookforinterfaces = 1;
continue;
}
ifs.int_dstaddr = ifreq.ifr_dstaddr;
}
/*
* already known to us?
* This allows multiple point-to-point links
* to share a source address (possibly with one
* other link), but assumes that there will not be
* multiple links with the same destination address.
*/
if (ifs.int_flags & IFF_POINTOPOINT) {
if (if_ifwithdstaddr(&ifs.int_dstaddr))
continue;
} else if (if_ifwithaddr(&ifs.int_addr))
continue;
if (ifs.int_flags & IFF_LOOPBACK) {
ifs.int_flags |= IFF_PASSIVE;
foundloopback = 1;
loopaddr = ifs.int_addr;
for (ifp = ifnet; ifp; ifp = ifp->int_next)
if (ifp->int_flags & IFF_POINTOPOINT)
add_ptopt_localrt(ifp);
}
if (ifs.int_flags & IFF_BROADCAST) {
if (ioctl(s, SIOCGIFBRDADDR, (char *)&ifreq) < 0) {
syslog(LOG_ERR, "%s: ioctl (get broadaddr)",
ifr->ifr_name);
continue;
}
#ifndef sun
ifs.int_broadaddr = ifreq.ifr_broadaddr;
#else
ifs.int_broadaddr = ifreq.ifr_addr;
#endif
}
#ifdef SIOCGIFMETRIC
if (ioctl(s, SIOCGIFMETRIC, (char *)&ifreq) < 0) {
syslog(LOG_ERR, "%s: ioctl (get metric)",
ifr->ifr_name);
ifs.int_metric = 0;
} else
ifs.int_metric = ifreq.ifr_metric;
#else
ifs.int_metric = 0;
#endif
/*
* Use a minimum metric of one;
* treat the interface metric (default 0)
* as an increment to the hop count of one.
*/
ifs.int_metric++;
if (ioctl(s, SIOCGIFNETMASK, (char *)&ifreq) < 0) {
syslog(LOG_ERR, "%s: ioctl (get netmask)",
ifr->ifr_name);
continue;
}
sin = (struct sockaddr_in *)&ifreq.ifr_addr;
ifs.int_subnetmask = ntohl(sin->sin_addr.s_addr);
sin = (struct sockaddr_in *)&ifs.int_addr;
i = ntohl(sin->sin_addr.s_addr);
if (IN_CLASSA(i))
ifs.int_netmask = IN_CLASSA_NET;
else if (IN_CLASSB(i))
ifs.int_netmask = IN_CLASSB_NET;
else
ifs.int_netmask = IN_CLASSC_NET;
ifs.int_net = i & ifs.int_netmask;
ifs.int_subnet = i & ifs.int_subnetmask;
if (ifs.int_subnetmask != ifs.int_netmask)
ifs.int_flags |= IFF_SUBNET;
ifp = (struct interface *)malloc(sizeof (struct interface));
if (ifp == 0) {
printf("routed: out of memory\n");
break;
}
*ifp = ifs;
/*
* Count the # of directly connected networks
* and point to point links which aren't looped
* back to ourself. This is used below to
* decide if we should be a routing ``supplier''.
*/
if ((ifs.int_flags & IFF_LOOPBACK) == 0 &&
((ifs.int_flags & IFF_POINTOPOINT) == 0 ||
if_ifwithaddr(&ifs.int_dstaddr) == 0))
externalinterfaces++;
/*
* If we have a point-to-point link, we want to act
* as a supplier even if it's our only interface,
* as that's the only way our peer on the other end
* can tell that the link is up.
*/
if ((ifs.int_flags & IFF_POINTOPOINT) && supplier < 0)
supplier = 1;
ifp->int_name = malloc(strlen(ifr->ifr_name) + 1);
if (ifp->int_name == 0) {
fprintf(stderr, "routed: ifinit: out of memory\n");
syslog(LOG_ERR, "routed: ifinit: out of memory\n");
close(s);
return;
}
strcpy(ifp->int_name, ifr->ifr_name);
*ifnext = ifp;
ifnext = &ifp->int_next;
traceinit(ifp);
addrouteforif(ifp);
}
if (externalinterfaces > 1 && supplier < 0)
supplier = 1;
close(s);
}
/*
* Add route for interface if not currently installed.
* Create route to other end if a point-to-point link,
* otherwise a route to this (sub)network.
* INTERNET SPECIFIC.
*/
addrouteforif(ifp)
register struct interface *ifp;
{
struct sockaddr_in net;
struct sockaddr *dst;
int state;
register struct rt_entry *rt;
if (ifp->int_flags & IFF_POINTOPOINT)
dst = &ifp->int_dstaddr;
else {
bzero((char *)&net, sizeof (net));
net.sin_family = AF_INET;
net.sin_addr = inet_makeaddr(ifp->int_subnet, INADDR_ANY);
dst = (struct sockaddr *)&net;
}
rt = rtfind(dst);
if (rt &&
(rt->rt_state & (RTS_INTERFACE | RTS_INTERNAL)) == RTS_INTERFACE)
return;
if (rt)
rtdelete(rt);
/*
* If interface on subnetted network,
* install route to network as well.
* This is meant for external viewers.
*/
if ((ifp->int_flags & (IFF_SUBNET|IFF_POINTOPOINT)) == IFF_SUBNET) {
struct in_addr subnet;
subnet = net.sin_addr;
net.sin_addr = inet_makeaddr(ifp->int_net, INADDR_ANY);
rt = rtfind(dst);
if (rt == 0)
rtadd(dst, &ifp->int_addr, ifp->int_metric,
((ifp->int_flags & (IFF_INTERFACE|IFF_REMOTE)) |
RTS_PASSIVE | RTS_INTERNAL | RTS_SUBNET));
else if ((rt->rt_state & (RTS_INTERNAL|RTS_SUBNET)) ==
(RTS_INTERNAL|RTS_SUBNET) &&
ifp->int_metric < rt->rt_metric)
rtchange(rt, &rt->rt_router, ifp->int_metric);
net.sin_addr = subnet;
}
if (ifp->int_transitions++ > 0)
syslog(LOG_ERR, "re-installing interface %s", ifp->int_name);
state = ifp->int_flags &
(IFF_INTERFACE | IFF_PASSIVE | IFF_REMOTE | IFF_SUBNET);
if (ifp->int_flags & IFF_POINTOPOINT &&
(ntohl(((struct sockaddr_in *)&ifp->int_dstaddr)->sin_addr.s_addr) &
ifp->int_netmask) != ifp->int_net)
state &= ~RTS_SUBNET;
if (ifp->int_flags & IFF_LOOPBACK)
state |= RTS_EXTERNAL;
rtadd(dst, &ifp->int_addr, ifp->int_metric, state);
if (ifp->int_flags & IFF_POINTOPOINT && foundloopback)
add_ptopt_localrt(ifp);
}
/*
* Add route to local end of point-to-point using loopback.
* If a route to this network is being sent to neighbors on other nets,
* mark this route as subnet so we don't have to propagate it too.
*/
add_ptopt_localrt(ifp)
register struct interface *ifp;
{
struct rt_entry *rt;
struct sockaddr *dst;
struct sockaddr_in net;
int state;
state = RTS_INTERFACE | RTS_PASSIVE;
/* look for route to logical network */
bzero((char *)&net, sizeof (net));
net.sin_family = AF_INET;
net.sin_addr = inet_makeaddr(ifp->int_net, INADDR_ANY);
dst = (struct sockaddr *)&net;
rt = rtfind(dst);
if (rt && rt->rt_state & RTS_INTERNAL)
state |= RTS_SUBNET;
dst = &ifp->int_addr;
if (rt = rtfind(dst)) {
if (rt && rt->rt_state & RTS_INTERFACE)
return;
rtdelete(rt);
}
rtadd(dst, &loopaddr, 1, state);
}
/*
* As a concession to the ARPANET we read a list of gateways
* from /etc/gateways and add them to our tables. This file
* exists at each ARPANET gateway and indicates a set of ``remote''
* gateways (i.e. a gateway which we can't immediately determine
* if it's present or not as we can do for those directly connected
* at the hardware level). If a gateway is marked ``passive''
* in the file, then we assume it doesn't have a routing process
* of our design and simply assume it's always present. Those
* not marked passive are treated as if they were directly
* connected -- they're added into the interface list so we'll
* send them routing updates.
*
* PASSIVE ENTRIES AREN'T NEEDED OR USED ON GATEWAYS RUNNING EGP.
*/
gwkludge()
{
struct sockaddr_in dst, gate;
FILE *fp;
char *type, *dname, *gname, *qual, buf[BUFSIZ];
struct interface *ifp;
int metric, n;
struct rt_entry route;
fp = fopen(_PATH_GATEWAYS, "r");
if (fp == NULL)
return;
qual = buf;
dname = buf + 64;
gname = buf + ((BUFSIZ - 64) / 3);
type = buf + (((BUFSIZ - 64) * 2) / 3);
bzero((char *)&dst, sizeof (dst));
bzero((char *)&gate, sizeof (gate));
bzero((char *)&route, sizeof(route));
/* format: {net | host} XX gateway XX metric DD [passive | external]\n */
#define readentry(fp) \
fscanf((fp), "%s %s gateway %s metric %d %s\n", \
type, dname, gname, &metric, qual)
for (;;) {
if ((n = readentry(fp)) == EOF)
break;
if (!getnetorhostname(type, dname, &dst))
continue;
if (!gethostnameornumber(gname, &gate))
continue;
if (metric == 0) /* XXX */
metric = 1;
if (strcmp(qual, "passive") == 0) {
/*
* Passive entries aren't placed in our tables,
* only the kernel's, so we don't copy all of the
* external routing information within a net.
* Internal machines should use the default
* route to a suitable gateway (like us).
*/
route.rt_dst = *(struct sockaddr *) &dst;
route.rt_router = *(struct sockaddr *) &gate;
route.rt_flags = RTF_UP;
if (strcmp(type, "host") == 0)
route.rt_flags |= RTF_HOST;
if (metric)
route.rt_flags |= RTF_GATEWAY;
(void) ioctl(s, SIOCADDRT, (char *)&route.rt_rt);
continue;
}
if (strcmp(qual, "external") == 0) {
/*
* Entries marked external are handled
* by other means, e.g. EGP,
* and are placed in our tables only
* to prevent overriding them
* with something else.
*/
rtadd(&dst, &gate, metric, RTS_EXTERNAL|RTS_PASSIVE);
continue;
}
/* assume no duplicate entries */
externalinterfaces++;
ifp = (struct interface *)malloc(sizeof (*ifp));
bzero((char *)ifp, sizeof (*ifp));
ifp->int_flags = IFF_REMOTE;
/* can't identify broadcast capability */
ifp->int_net = inet_netof(dst.sin_addr);
if (strcmp(type, "host") == 0) {
ifp->int_flags |= IFF_POINTOPOINT;
ifp->int_dstaddr = *((struct sockaddr *)&dst);
}
ifp->int_addr = *((struct sockaddr *)&gate);
ifp->int_metric = metric;
ifp->int_next = ifnet;
ifnet = ifp;
addrouteforif(ifp);
}
fclose(fp);
}
getnetorhostname(type, name, sin)
char *type, *name;
struct sockaddr_in *sin;
{
if (strcmp(type, "net") == 0) {
struct netent *np = getnetbyname(name);
int n;
if (np == 0)
n = inet_network(name);
else {
if (np->n_addrtype != AF_INET)
return (0);
n = np->n_net;
/*
* getnetbyname returns right-adjusted value.
*/
if (n < 128)
n <<= IN_CLASSA_NSHIFT;
else if (n < 65536)
n <<= IN_CLASSB_NSHIFT;
else
n <<= IN_CLASSC_NSHIFT;
}
sin->sin_family = AF_INET;
sin->sin_addr = inet_makeaddr(n, INADDR_ANY);
return (1);
}
if (strcmp(type, "host") == 0) {
struct hostent *hp = gethostbyname(name);
if (hp == 0)
sin->sin_addr.s_addr = inet_addr(name);
else {
if (hp->h_addrtype != AF_INET)
return (0);
bcopy(hp->h_addr, &sin->sin_addr, hp->h_length);
}
sin->sin_family = AF_INET;
return (1);
}
return (0);
}
gethostnameornumber(name, sin)
char *name;
struct sockaddr_in *sin;
{
struct hostent *hp;
hp = gethostbyname(name);
if (hp) {
bcopy(hp->h_addr, &sin->sin_addr, hp->h_length);
sin->sin_family = hp->h_addrtype;
return (1);
}
sin->sin_addr.s_addr = inet_addr(name);
sin->sin_family = AF_INET;
return (sin->sin_addr.s_addr != -1);
}