/*
* Use getifaddrs() to get a list of all the attached interfaces. For
* each interface that's of type INET and not the loopback interface,
* register that interface with the network I/O software, figure out
* what subnet it's on, and add it to the list of interfaces.
*/
void
discover_interfaces(struct interface_info *iface)
{
struct ifaddrs *ifap, *ifa;
struct sockaddr_in foo;
struct ifreq *tif;
if (getifaddrs(&ifap) != 0)
error("getifaddrs failed");
for (ifa = ifap; ifa != NULL; ifa = ifa->ifa_next) {
if ((ifa->ifa_flags & IFF_LOOPBACK) ||
(ifa->ifa_flags & IFF_POINTOPOINT) ||
(!(ifa->ifa_flags & IFF_UP)))
continue;
if (strcmp(iface->name, ifa->ifa_name))
continue;
/*
* If we have the capability, extract link information
* and record it in a linked list.
*/
if (ifa->ifa_addr->sa_family == AF_LINK) {
struct sockaddr_dl *foo =
(struct sockaddr_dl *)ifa->ifa_addr;
iface->index = foo->sdl_index;
iface->hw_address.hlen = foo->sdl_alen;
iface->hw_address.htype = HTYPE_ETHER; /* XXX */
memcpy(iface->hw_address.haddr,
LLADDR(foo), foo->sdl_alen);
} else if (ifa->ifa_addr->sa_family == AF_INET) {
struct iaddr addr;
memcpy(&foo, ifa->ifa_addr, sizeof(foo));
if (foo.sin_addr.s_addr == htonl(INADDR_LOOPBACK))
continue;
if (!iface->ifp) {
int len = IFNAMSIZ + ifa->ifa_addr->sa_len;
if ((tif = malloc(len)) == NULL)
error("no space to remember ifp");
strlcpy(tif->ifr_name, ifa->ifa_name, IFNAMSIZ);
memcpy(&tif->ifr_addr, ifa->ifa_addr,
ifa->ifa_addr->sa_len);
iface->ifp = tif;
iface->primary_address = foo.sin_addr;
}
addr.len = 4;
memcpy(addr.iabuf, &foo.sin_addr.s_addr, addr.len);
}
}
if (!iface->ifp)
error("%s: not found", iface->name);
/* Register the interface... */
if_register_receive(iface);
if_register_send(iface);
add_protocol(iface->name, iface->rfdesc, got_one, iface);
freeifaddrs(ifap);
}
void
discover_interfaces(int *rdomain)
{
struct interface_info *tmp;
struct interface_info *last, *next;
struct subnet *subnet;
struct shared_network *share;
struct sockaddr_in foo;
int ir = 0, ird;
struct ifreq *tif;
struct ifaddrs *ifap, *ifa;
if (getifaddrs(&ifap) != 0)
error("getifaddrs failed");
/*
* If we already have a list of interfaces, the interfaces were
* requested.
*/
if (interfaces != NULL)
ir = 1;
else
/* must specify an interface when rdomains are used */
*rdomain = 0;
/* Cycle through the list of interfaces looking for IP addresses. */
for (ifa = ifap; ifa != NULL; ifa = ifa->ifa_next) {
/*
* See if this is the sort of interface we want to
* deal with. Skip loopback, point-to-point and down
* interfaces, except don't skip down interfaces if we're
* trying to get a list of configurable interfaces.
*/
if ((ifa->ifa_flags & IFF_LOOPBACK) ||
(ifa->ifa_flags & IFF_POINTOPOINT) ||
(!(ifa->ifa_flags & IFF_UP)) ||
(!(ifa->ifa_flags & IFF_BROADCAST)))
continue;
/* See if we've seen an interface that matches this one. */
for (tmp = interfaces; tmp; tmp = tmp->next)
if (!strcmp(tmp->name, ifa->ifa_name))
break;
/* If we are looking for specific interfaces, ignore others. */
if (tmp == NULL && ir)
continue;
ird = get_rdomain(ifa->ifa_name);
if (*rdomain == -1)
*rdomain = ird;
else if (*rdomain != ird && ir)
error("Interface %s is not in rdomain %d",
tmp->name, *rdomain);
else if (*rdomain != ird && !ir)
continue;
/* If there isn't already an interface by this name,
allocate one. */
if (tmp == NULL) {
tmp = calloc(1, sizeof *tmp);
if (!tmp)
error("Insufficient memory to %s %s",
"record interface", ifa->ifa_name);
strlcpy(tmp->name, ifa->ifa_name, sizeof(tmp->name));
tmp->next = interfaces;
tmp->noifmedia = tmp->dead = tmp->errors = 0;
interfaces = tmp;
}
/* If we have the capability, extract link information
and record it in a linked list. */
if (ifa->ifa_addr->sa_family == AF_LINK) {
struct sockaddr_dl *foo =
((struct sockaddr_dl *)(ifa->ifa_addr));
tmp->index = foo->sdl_index;
tmp->hw_address.hlen = foo->sdl_alen;
tmp->hw_address.htype = HTYPE_ETHER; /* XXX */
memcpy(tmp->hw_address.haddr,
LLADDR(foo), foo->sdl_alen);
} else if (ifa->ifa_addr->sa_family == AF_INET) {
struct iaddr addr;
/* Get a pointer to the address... */
memcpy(&foo, ifa->ifa_addr, sizeof(foo));
/* We don't want the loopback interface. */
if (foo.sin_addr.s_addr == htonl (INADDR_LOOPBACK))
continue;
/* If this is the first real IP address we've
found, keep a pointer to ifreq structure in
which we found it. */
if (!tmp->ifp) {
int len = (IFNAMSIZ + ifa->ifa_addr->sa_len);
tif = (struct ifreq *)malloc(len);
if (!tif)
error("no space to remember ifp.");
strlcpy(tif->ifr_name, ifa->ifa_name, IFNAMSIZ);
memcpy(&tif->ifr_addr, ifa->ifa_addr,
ifa->ifa_addr->sa_len);
tmp->ifp = tif;
tmp->primary_address = foo.sin_addr;
}
/* Grab the address... */
addr.len = 4;
memcpy(addr.iabuf, &foo.sin_addr.s_addr, addr.len);
/* If there's a registered subnet for this address,
connect it together... */
if ((subnet = find_subnet(addr))) {
/* If this interface has multiple aliases
on the same subnet, ignore all but the
first we encounter. */
if (!subnet->interface) {
subnet->interface = tmp;
subnet->interface_address = addr;
} else if (subnet->interface != tmp) {
warning("Multiple %s %s: %s %s",
"interfaces match the",
"same subnet",
subnet->interface->name,
tmp->name);
}
share = subnet->shared_network;
if (tmp->shared_network &&
tmp->shared_network != share) {
warning("Interface %s matches %s",
tmp->name,
"multiple shared networks");
} else {
tmp->shared_network = share;
}
if (!share->interface) {
share->interface = tmp;
} else if (share->interface != tmp) {
warning("Multiple %s %s: %s %s",
"interfaces match the",
"same shared network",
share->interface->name,
tmp->name);
}
}
}
}
/* Discard interfaces we can't listen on. */
last = NULL;
for (tmp = interfaces; tmp; tmp = next) {
next = tmp->next;
if (!tmp->ifp) {
warning("Can't listen on %s - it has no IP address.",
tmp->name);
/* Remove tmp from the list of interfaces. */
if (!last)
interfaces = interfaces->next;
else
last->next = tmp->next;
continue;
}
memcpy(&foo, &tmp->ifp->ifr_addr, sizeof tmp->ifp->ifr_addr);
if (!tmp->shared_network) {
warning("Can't listen on %s - dhcpd.conf has no subnet "
"declaration for %s.", tmp->name,
inet_ntoa(foo.sin_addr));
/* Remove tmp from the list of interfaces. */
if (!last)
interfaces = interfaces->next;
else
last->next = tmp->next;
continue;
}
last = tmp;
/* Find subnets that don't have valid interface addresses. */
for (subnet = (tmp->shared_network ? tmp->shared_network->subnets :
NULL); subnet; subnet = subnet->next_sibling) {
if (!subnet->interface_address.len) {
/*
* Set the interface address for this subnet
* to the first address we found.
*/
subnet->interface_address.len = 4;
memcpy(subnet->interface_address.iabuf,
&foo.sin_addr.s_addr, 4);
}
}
/* Register the interface... */
if_register_receive(tmp);
if_register_send(tmp);
note("Listening on %s (%s).", tmp->name,
inet_ntoa(foo.sin_addr));
}
if (interfaces == NULL)
error("No interfaces to listen on.");
/* Now register all the remaining interfaces as protocols. */
for (tmp = interfaces; tmp; tmp = tmp->next)
add_protocol(tmp->name, tmp->rfdesc, got_one, tmp);
freeifaddrs(ifap);
}
