2.11BSD/src/sbin/routed/startup.c
/*
* Copyright (c) 1983 Regents of the University of California.
* All rights reserved. The Berkeley software License Agreement
* specifies the terms and conditions for redistribution.
*/
#if !defined(lint) && defined(DOSCCS)
static char sccsid[] = "@(#)startup.c 5.7.1 (2.11BSD) 1996/11/19";
#endif not lint
/*
* Routing Table Management Daemon
*/
#include "defs.h"
#include <sys/ioctl.h>
#include <net/if.h>
#include <syslog.h>
struct interface *ifnet;
int lookforinterfaces = 1;
int externalinterfaces = 0; /* # of remote and local interfaces */
/*
* 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, n;
char buf[BUFSIZ];
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");
exit(1);
}
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 (0);
}
ifr = ifc.ifc_req;
lookforinterfaces = 0;
for (n = ifc.ifc_len / sizeof (struct ifreq); n > 0; n--, ifr++) {
bzero((char *)&ifs, sizeof(ifs));
ifs.int_addr = ifr->ifr_addr;
ifreq = *ifr;
if (ioctl(s, SIOCGIFFLAGS, (char *)&ifreq) < 0) {
syslog(LOG_ERR, "ioctl (get interface flags)");
continue;
}
ifs.int_flags = ifreq.ifr_flags | IFF_INTERFACE;
/* no one cares about software loopback interfaces */
if (ifs.int_flags & IFF_LOOPBACK)
continue;
if ((ifs.int_flags & IFF_UP) == 0 ||
ifr->ifr_addr.sa_family == AF_UNSPEC) {
lookforinterfaces = 1;
continue;
}
/* already known to us? */
if (if_ifwithaddr(&ifs.int_addr))
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, "ioctl (get dstaddr)");
continue;
}
ifs.int_dstaddr = ifreq.ifr_dstaddr;
}
if (ifs.int_flags & IFF_BROADCAST) {
if (ioctl(s, SIOCGIFBRDADDR, (char *)&ifreq) < 0) {
syslog(LOG_ERR, "ioctl (get broadaddr)");
continue;
}
ifs.int_broadaddr = ifreq.ifr_broadaddr;
}
if (ioctl(s, SIOCGIFMETRIC, (char *)&ifreq) < 0)
syslog(LOG_ERR, "ioctl (get metric)");
else
ifs.int_metric = ifreq.ifr_metric;
if (ioctl(s, SIOCGIFNETMASK, (char *)&ifreq) < 0) {
syslog(LOG_ERR, "ioctl (get netmask)");
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_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");
goto bad; /* ??? */
}
strcpy(ifp->int_name, ifr->ifr_name);
ifp->int_next = ifnet;
ifnet = ifp;
traceinit(ifp);
addrouteforif(ifp);
}
if (externalinterfaces > 1 && supplier < 0)
supplier = 1;
close(s);
return;
bad:
sleep(60);
close(kmem), close(s);
execv("/sbin/routed", argv0);
_exit(0177);
}
/*
* 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)
struct interface *ifp;
{
struct sockaddr_in net;
struct sockaddr *dst;
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) {
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));
net.sin_addr = inet_makeaddr(ifp->int_subnet, INADDR_ANY);
}
if (ifp->int_transitions++ > 0)
syslog(LOG_ERR, "re-installing interface %s", ifp->int_name);
rtadd(dst, &ifp->int_addr, ifp->int_metric,
ifp->int_flags & (IFF_INTERFACE|IFF_PASSIVE|IFF_REMOTE|IFF_SUBNET));
}
/*
* 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.
*/
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("/etc/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]\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 (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);
u_long 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);
}