The multicast router. Stick it next to routed and XNSrouted since that
[unix-history] / sbin / mrouted / config.c
/*
* The mrouted program is covered by the license in the accompanying file
* named "LICENSE". Use of the mrouted program represents acceptance of
* the terms and conditions listed in that file.
*
* The mrouted program is COPYRIGHT 1989 by The Board of Trustees of
* Leland Stanford Junior University.
*
*
* $Id: config.c,v 1.3 1993/05/30 01:36:38 deering Exp $
*/
#include "defs.h"
char *configfilename = "/etc/mrouted.conf";
/*
* Forward declarations.
*/
static char *next_word();
/*
* Query the kernel to find network interfaces that are multicast-capable
* and install them in the uvifs array.
*/
void config_vifs_from_kernel()
{
struct ifreq ifbuf[32];
struct ifreq *ifrp, *ifend, *mp;
struct ifconf ifc;
register struct uvif *v;
register vifi_t vifi;
int i, n;
u_long addr, mask, subnet;
u_int flags;
ifc.ifc_buf = (char *)ifbuf;
ifc.ifc_len = sizeof(ifbuf);
if (ioctl(udp_socket, SIOCGIFCONF, (char *)&ifc) < 0)
log(LOG_ERR, errno, "ioctl SIOCGIFCONF");
ifrp = (struct ifreq *)ifbuf;
ifend = (struct ifreq *)((char *)ifbuf + ifc.ifc_len);
/*
* Loop through all of the interfaces.
*/
for (; ifrp < ifend; ifrp = (struct ifreq *)((char *)ifrp + n)) {
struct ifreq ifr;
#if BSD >= 199006
n = ifrp->ifr_addr.sa_len + sizeof(ifrp->ifr_name);
if (n < sizeof(*ifrp))
n = sizeof(*ifrp);
#else
n = sizeof(*ifrp);
#endif
/*
* Ignore any interface for an address family other than IP.
*/
addr = ((struct sockaddr_in *)&ifrp->ifr_addr)->sin_addr.s_addr;
if (ifrp->ifr_addr.sa_family != AF_INET)
continue;
/*
* Need a template to preserve address info that is
* used below to locate the next entry. (Otherwise,
* SIOCGIFFLAGS stomps over it because the requests
* are returned in a union.)
*/
bcopy(ifrp->ifr_name, ifr.ifr_name, sizeof(ifr.ifr_name));
/*
* Ignore loopback interfaces and interfaces that do not support
* multicast.
*/
if (ioctl(udp_socket, SIOCGIFFLAGS, (char *)&ifr) < 0)
log(LOG_ERR, errno, "ioctl SIOCGIFFLAGS for %s", ifr.ifr_name);
flags = ifr.ifr_flags;
if ((flags & (IFF_LOOPBACK|IFF_MULTICAST)) != IFF_MULTICAST) continue;
/*
* Ignore any interface whose address and mask do not define a
* valid subnet number, or whose address is of the form {subnet,0}
* or {subnet,-1}.
*/
if (ioctl(udp_socket, SIOCGIFNETMASK, (char *)&ifr) < 0)
log(LOG_ERR, errno, "ioctl SIOCGIFNETMASK for %s", ifr.ifr_name);
mask = ((struct sockaddr_in *)&ifr.ifr_addr)->sin_addr.s_addr;
subnet = addr & mask;
if (!inet_valid_subnet(subnet, mask) ||
addr == subnet ||
addr == (subnet | ~mask)) {
log(LOG_WARNING, 0,
"ignoring %s, has invalid address (%s) and/or mask (%08x)",
ifr.ifr_name, inet_fmt(addr, s1), ntohl(mask));
continue;
}
/*
* Ignore any interface that is connected to the same subnet as
* one already installed in the uvifs array.
*/
for (vifi = 0, v = uvifs; vifi < numvifs; ++vifi, ++v) {
if ((addr & v->uv_subnetmask) == v->uv_subnet ||
(v->uv_subnet & mask) == subnet) {
log(LOG_WARNING, 0, "ignoring %s, same subnet as %s",
ifr.ifr_name, v->uv_name);
break;
}
}
if (vifi != numvifs) continue;
/*
* If there is room in the uvifs array, install this interface.
*/
if (numvifs == MAXVIFS) {
log(LOG_WARNING, 0, "too many vifs, ignoring %s", ifr.ifr_name);
continue;
}
v = &uvifs[numvifs];
v->uv_flags = 0;
v->uv_metric = DEFAULT_METRIC;
v->uv_threshold = DEFAULT_THRESHOLD;
v->uv_lcl_addr = addr;
v->uv_rmt_addr = 0;
v->uv_subnet = subnet;
v->uv_subnetmask = mask;
v->uv_subnetbcast = subnet | ~mask;
strncpy(v->uv_name, ifr.ifr_name, IFNAMSIZ);
v->uv_groups = NULL;
v->uv_neighbors = NULL;
log(LOG_INFO, 0, "installing %s (%s on subnet %s) as vif #%u",
v->uv_name, inet_fmt(addr, s1), inet_fmts(subnet, mask, s2),
numvifs);
++numvifs;
/*
* If the interface is not yet up, set the vifs_down flag to
* remind us to check again later.
*/
if (!(flags & IFF_UP)) {
v->uv_flags |= VIFF_DOWN;
vifs_down = TRUE;
}
}
}
static struct ifreq *
ifconfaddr(ifcp, a)
struct ifconf *ifcp;
u_long a;
{
int n;
struct ifreq *ifrp = (struct ifreq *)ifcp->ifc_buf;
struct ifreq *ifend = (struct ifreq *)((char *)ifrp + ifcp->ifc_len);
while (ifrp < ifend) {
if (ifrp->ifr_addr.sa_family == AF_INET &&
((struct sockaddr_in *)&ifrp->ifr_addr)->sin_addr.s_addr == a)
return (ifrp);
#if BSD >= 199006
n = ifrp->ifr_addr.sa_len + sizeof(ifrp->ifr_name);
if (n < sizeof(*ifrp))
++ifrp;
else
ifrp = (struct ifreq *)((char *)ifrp + n);
#else
++ifrp;
#endif
}
return (0);
}
/*
* Read the config file to learn about tunnel vifs and
* non-default phyint parameters.
*/
void config_vifs_from_file()
{
FILE *f;
char linebuf[100];
char *w, *s, c;
u_long lcl_addr, rmt_addr;
struct ifconf ifc;
struct ifreq *ifr;
struct ifreq ffr;
int i;
u_int n;
struct ifreq ifbuf[32];
vifi_t vifi;
struct uvif *v;
f = fopen(configfilename, "r");
if (f == NULL) {
if (errno != ENOENT)
log(LOG_WARNING, errno, "can't open %s", configfilename);
return;
}
ifc.ifc_buf = (char *)ifbuf;
ifc.ifc_len = sizeof(ifbuf);
if (ioctl(udp_socket, SIOCGIFCONF, (char *)&ifc) < 0)
log(LOG_ERR, errno, "ioctl SIOCGIFCONF");
while (fgets(linebuf, sizeof(linebuf), f) != NULL) {
s = linebuf;
if (EQUAL((w = next_word(&s)), "")) {
/*
* blank or comment line; ignore
*/
}
else if (EQUAL(w, "phyint")) {
/*
* phyint <local-addr> [disable] [metric <m>] [threshold <t>]
*/
/*
* Parse the local address.
*/
if (EQUAL((w = next_word(&s)), "")) {
log(LOG_WARNING, 0,
"missing phyint address in %s",
configfilename);
continue;
}
if ((lcl_addr = inet_parse(w)) == 0xffffffff ||
!inet_valid_host(lcl_addr)) {
log(LOG_WARNING, 0,
"invalid phyint address '%s' in %s",
w, configfilename);
continue;
}
/*
* Look up the vif with the specified local address.
*/
for (vifi = 0, v = uvifs; vifi < numvifs; ++vifi, ++v) {
if (!(v->uv_flags & VIFF_TUNNEL) &&
lcl_addr == v->uv_lcl_addr) {
break;
}
}
if (vifi == numvifs) {
log(LOG_WARNING, 0,
"phyint %s in %s is not a configured interface",
inet_fmt(lcl_addr, s1), configfilename);
continue;
}
/*
* Look for "disable", "metric" and "threshold" options.
*/
while (!EQUAL((w = next_word(&s)), "")) {
if (EQUAL(w, "disable")) {
v->uv_flags |= VIFF_DISABLED;
}
else if (EQUAL(w, "metric")) {
if(EQUAL((w = next_word(&s)), "")) {
log(LOG_WARNING, 0,
"missing metric for phyint %s in %s",
inet_fmt(lcl_addr, s1), configfilename);
w = "garbage";
break;
}
if(sscanf(w, "%u%c", &n, &c) != 1 ||
n < 1 || n >= UNREACHABLE ) {
log(LOG_WARNING, 0,
"invalid metric '%s' for phyint %s in %s",
w, inet_fmt(lcl_addr, s1), configfilename);
break;
}
v->uv_metric = n;
}
else if (EQUAL(w, "threshold")) {
if(EQUAL((w = next_word(&s)), "")) {
log(LOG_WARNING, 0,
"missing threshold for phyint %s in %s",
inet_fmt(lcl_addr, s1), configfilename);
w = "garbage";
break;
}
if(sscanf(w, "%u%c", &n, &c) != 1 ||
n < 1 || n > 255 ) {
log(LOG_WARNING, 0,
"invalid threshold '%s' for phyint %s in %s",
w, inet_fmt(lcl_addr, s1), configfilename);
break;
}
v->uv_threshold = n;
}
else break;
}
if (!EQUAL(w, "")) continue;
}
else if (EQUAL(w, "tunnel")) {
/*
* tunnel <local-addr> <remote-addr> [srcrt] [metric <m>] [threshold <t>]
*/
/*
* Parse the local address.
*/
if (EQUAL((w = next_word(&s)), "")) {
log(LOG_WARNING, 0,
"missing tunnel local address in %s",
configfilename);
continue;
}
if ((lcl_addr = inet_parse(w)) == 0xffffffff ||
!inet_valid_host(lcl_addr)) {
log(LOG_WARNING, 0,
"invalid tunnel local address '%s' in %s",
w, configfilename);
continue;
}
/*
* Make sure the local address is one of ours.
*/
ifr = ifconfaddr(&ifc, lcl_addr);
if (ifr == 0) {
log(LOG_WARNING, 0,
"tunnel local address %s in %s is not one of ours",
inet_fmt(lcl_addr, s1), configfilename);
continue;
}
/*
* Make sure the local address doesn't name a loopback interface..
*/
strncpy(ffr.ifr_name, ifr->ifr_name, IFNAMSIZ);
if (ioctl(udp_socket, SIOCGIFFLAGS, (char *)&ffr) < 0) {
log(LOG_ERR, errno,
"ioctl SIOCGIFFLAGS for %s", ffr.ifr_name);
}
if (ffr.ifr_flags & IFF_LOOPBACK) {
log(LOG_WARNING, 0,
"tunnel local address %s in %s is a loopback interface",
inet_fmt(lcl_addr, s1), configfilename);
continue;
}
/*
* Parse the remote address.
*/
if (EQUAL((w = next_word(&s)), "")) {
log(LOG_WARNING, 0,
"missing tunnel remote address in %s",
configfilename);
continue;
}
if ((rmt_addr = inet_parse(w)) == 0xffffffff ||
!inet_valid_host(rmt_addr)) {
log(LOG_WARNING, 0,
"invalid tunnel remote address %s in %s",
w, configfilename);
continue;
}
/*
* Make sure the remote address is not one of ours.
*/
if (ifconfaddr(&ifc, rmt_addr) != 0) {
log(LOG_WARNING, 0,
"tunnel remote address %s in %s is one of ours",
inet_fmt(rmt_addr, s1), configfilename);
continue;
}
/*
* Make sure the remote address has not been used for another
* tunnel and does not belong to a subnet to which we have direct
* access on an enabled phyint.
*/
for (vifi = 0, v = uvifs; vifi < numvifs; ++vifi, ++v) {
if (v->uv_flags & VIFF_TUNNEL) {
if (rmt_addr == v->uv_rmt_addr) {
log(LOG_WARNING, 0,
"duplicate tunnel remote address %s in %s",
inet_fmt(rmt_addr, s1), configfilename);
break;
}
}
else if (!(v->uv_flags & VIFF_DISABLED)) {
if ((rmt_addr & v->uv_subnetmask) == v->uv_subnet) {
log(LOG_WARNING, 0,
"unnecessary tunnel remote address %s in %s",
inet_fmt(rmt_addr, s1), configfilename);
break;
}
}
}
if (vifi != numvifs) continue;
/*
* OK, let's initialize a uvif structure for the tunnel.
*/
if (numvifs == MAXVIFS) {
log(LOG_WARNING, 0, "too many vifs, ignoring tunnel to %s",
inet_fmt(rmt_addr, s1));
continue;
}
v = &uvifs[numvifs];
v->uv_flags = VIFF_TUNNEL;
v->uv_metric = DEFAULT_METRIC;
v->uv_threshold = DEFAULT_THRESHOLD;
v->uv_lcl_addr = lcl_addr;
v->uv_rmt_addr = rmt_addr;
v->uv_subnet = 0;
v->uv_subnetmask = 0;
v->uv_subnetbcast = 0;
strncpy(v->uv_name, ffr.ifr_name, IFNAMSIZ);
v->uv_groups = NULL;
v->uv_neighbors = NULL;
/*
* Look for "metric" and "threshold" options.
*/
while (!EQUAL((w = next_word(&s)), "")) {
if (EQUAL(w, "metric")) {
if(EQUAL((w = next_word(&s)), "")) {
log(LOG_WARNING, 0,
"missing metric for tunnel to %s in %s",
inet_fmt(rmt_addr, s1), configfilename);
w = "garbage";
break;
}
if(sscanf(w, "%u%c", &n, &c) != 1 ||
n < 1 || n >= UNREACHABLE ) {
log(LOG_WARNING, 0,
"invalid metric '%s' for tunnel to %s in %s",
w, inet_fmt(rmt_addr, s1), configfilename);
break;
}
v->uv_metric = n;
}
else if (EQUAL(w, "threshold")) {
if(EQUAL((w = next_word(&s)), "")) {
log(LOG_WARNING, 0,
"missing threshold for tunnel to %s in %s",
inet_fmt(rmt_addr, s1), configfilename);
w = "garbage";
break;
}
if(sscanf(w, "%u%c", &n, &c) != 1 ||
n < 1 || n > 255 ) {
log(LOG_WARNING, 0,
"invalid threshold '%s' for tunnel to %s in %s",
w, inet_fmt(rmt_addr, s1), configfilename);
break;
}
v->uv_threshold = n;
}
else if (EQUAL(w, "srcrt") || EQUAL(w, "sourceroute")) {
v->uv_flags |= VIFF_SRCRT;
}
else break;
}
if (!EQUAL(w, "")) continue;
log(LOG_INFO, 0,
"installing %stunnel from %s to %s as vif #%u",
v->uv_flags & VIFF_SRCRT? "srcrt " : "",
inet_fmt(lcl_addr, s1), inet_fmt(rmt_addr, s2), numvifs);
++numvifs;
if (!(ffr.ifr_flags & IFF_UP)) {
v->uv_flags |= VIFF_DOWN;
vifs_down = TRUE;
}
}
else {
log(LOG_WARNING, 0,
"unknown command '%s' in %s", w, configfilename);
}
}
close(f);
}
/*
* Return a pointer to the next "word" in the string to which '*s' points,
* lower-cased and null terminated, and advance '*s' to point beyond the word.
* Words are separated by blanks and/or tabs, and the input string is
* considered to terminate at a newline, '#' (comment), or null character.
* If no words remain, a pointer to a null string ("") is returned.
* Warning: This function clobbers the input string.
*/
static char *next_word(s)
char **s;
{
char *w;
w = *s;
while (*w == ' ' || *w == '\t')
++w;
*s = w;
for(;;) {
switch (**s) {
case ' ' :
case '\t' : **s = '\0';
++*s;
return (w);
case '\n' :
case '#' : **s = '\0';
return (w);
case '\0' : return (w);
default : if (isascii(**s) && isupper(**s))
**s = tolower(**s);
++*s;
}
}
}