/*
* Print the contents of the routing table on file 'fp'.
*/
void
dump_routes(FILE *fp)
{
register struct rtentry *r;
register vifi_t i;
fprintf(fp,
"Multicast Routing Table (%u %s)\n%s\n",
nroutes, (nroutes == 1) ? "entry" : "entries",
" Origin-Subnet From-Gateway Metric Tmr In-Vif Out-Vifs");
for (r = routing_table; r != NULL; r = r->rt_next) {
fprintf(fp, " %-18s %-15s ",
inet_fmts(r->rt_origin, r->rt_originmask, s1),
(r->rt_gateway == 0) ? "" : inet_fmt(r->rt_gateway, s2));
fprintf(fp, (r->rt_metric == UNREACHABLE) ? " NR " : "%4u ",
r->rt_metric);
fprintf(fp, " %3u %3u ", r->rt_timer, r->rt_parent);
for (i = 0; i < numvifs; ++i) {
if (VIFM_ISSET(i, r->rt_children)) {
fprintf(fp, " %u%c",
i, VIFM_ISSET(i, r->rt_leaves) ? '*' : ' ');
}
}
fprintf(fp, "\n");
}
fprintf(fp, "\n");
}
/*
* Process an incoming route report message.
*/
void
accept_report(u_int32_t src, u_int32_t dst, char *p, int datalen,
u_int32_t level)
{
vifi_t vifi;
register int width, i, nrt = 0;
int metric;
u_int32_t mask;
u_int32_t origin;
struct newrt rt[4096];
if ((vifi = find_vif(src, dst)) == NO_VIF) {
logit(LOG_INFO, 0,
"ignoring route report from non-neighbor %s", inet_fmt(src, s1));
return;
}
if (!update_neighbor(vifi, src, DVMRP_REPORT, NULL, 0, level))
return;
if (datalen > 2*4096) {
logit(LOG_INFO, 0,
"ignoring oversize (%d bytes) route report from %s",
datalen, inet_fmt(src, s1));
return;
}
while (datalen > 0) { /* Loop through per-mask lists. */
if (datalen < 3) {
logit(LOG_WARNING, 0,
"received truncated route report from %s",
inet_fmt(src, s1));
return;
}
((u_char *)&mask)[0] = 0xff;
width = 1;
if ((((u_char *)&mask)[1] = *p++) != 0) width = 2;
if ((((u_char *)&mask)[2] = *p++) != 0) width = 3;
if ((((u_char *)&mask)[3] = *p++) != 0) width = 4;
if (!inet_valid_mask(ntohl(mask))) {
logit(LOG_WARNING, 0,
"%s reports bogus netmask 0x%08x (%s)",
inet_fmt(src, s1), ntohl(mask), inet_fmt(mask, s2));
return;
}
datalen -= 3;
do { /* Loop through (origin, metric) pairs */
if (datalen < width + 1) {
logit(LOG_WARNING, 0,
"received truncated route report from %s",
inet_fmt(src, s1));
return;
}
origin = 0;
for (i = 0; i < width; ++i)
((char *)&origin)[i] = *p++;
metric = *p++;
datalen -= width + 1;
rt[nrt].mask = mask;
rt[nrt].origin = origin;
rt[nrt].metric = (metric & 0x7f);
++nrt;
} while (!(metric & 0x80));
}
qsort((char*)rt, nrt, sizeof(rt[0]), compare_rts);
start_route_updates();
/*
* If the last entry is default, change mask from 0xff000000 to 0
*/
if (rt[nrt-1].origin == 0)
rt[nrt-1].mask = 0;
logit(LOG_DEBUG, 0, "Updating %d routes from %s to %s", nrt,
inet_fmt(src, s1), inet_fmt(dst, s2));
for (i = 0; i < nrt; ++i) {
if (i != 0 && rt[i].origin == rt[i-1].origin &&
rt[i].mask == rt[i-1].mask) {
logit(LOG_WARNING, 0, "%s reports duplicate route for %s",
inet_fmt(src, s1), inet_fmts(rt[i].origin, rt[i].mask, s2));
continue;
}
update_route(rt[i].origin, rt[i].mask, rt[i].metric,
src, vifi);
}
if (routes_changed && !delay_change_reports)
report_to_all_neighbors(CHANGED_ROUTES);
}
/*
* Process a route report for a single origin, creating or updating the
* corresponding routing table entry if necessary. 'src' is either the
* address of a neighboring router from which the report arrived, or zero
* to indicate a change of status of one of our own interfaces.
*/
void
update_route(u_int32_t origin, u_int32_t mask, u_int metric, u_int32_t src,
vifi_t vifi)
{
register struct rtentry *r;
u_int adj_metric;
/*
* Compute an adjusted metric, taking into account the cost of the
* subnet or tunnel over which the report arrived, and normalizing
* all unreachable/poisoned metrics into a single value.
*/
if (src != 0 && (metric < 1 || metric >= 2*UNREACHABLE)) {
logit(LOG_WARNING, 0,
"%s reports out-of-range metric %u for origin %s",
inet_fmt(src, s1), metric, inet_fmts(origin, mask, s2));
return;
}
adj_metric = metric + uvifs[vifi].uv_metric;
if (adj_metric > UNREACHABLE) adj_metric = UNREACHABLE;
/*
* Look up the reported origin in the routing table.
*/
if (!find_route(origin, mask)) {
/*
* Not found.
* Don't create a new entry if the report says it's unreachable,
* or if the reported origin and mask are invalid.
*/
if (adj_metric == UNREACHABLE) {
return;
}
if (src != 0 && !inet_valid_subnet(origin, mask)) {
logit(LOG_WARNING, 0,
"%s reports an invalid origin (%s) and/or mask (%08x)",
inet_fmt(src, s1), inet_fmt(origin, s2), ntohl(mask));
return;
}
/*
* OK, create the new routing entry. 'rtp' will be left pointing
* to the new entry.
*/
create_route(origin, mask);
/*
* Now "steal away" any sources that belong under this route
* by deleting any cache entries they might have created
* and allowing the kernel to re-request them.
*/
steal_sources(rtp);
rtp->rt_metric = UNREACHABLE; /* temporary; updated below */
}
/*
* We now have a routing entry for the reported origin. Update it?
*/
r = rtp;
if (r->rt_metric == UNREACHABLE) {
/*
* The routing entry is for a formerly-unreachable or new origin.
* If the report claims reachability, update the entry to use
* the reported route.
*/
if (adj_metric == UNREACHABLE)
return;
r->rt_parent = vifi;
init_children_and_leaves(r, vifi);
r->rt_gateway = src;
r->rt_timer = 0;
r->rt_metric = adj_metric;
r->rt_flags |= RTF_CHANGED;
routes_changed = TRUE;
update_table_entry(r);
}
else if (src == r->rt_gateway) {
/*
* The report has come either from the interface directly-connected
* to the origin subnet (src and r->rt_gateway both equal zero) or
* from the gateway we have chosen as the best first-hop gateway back
* towards the origin (src and r->rt_gateway not equal zero). Reset
* the route timer and, if the reported metric has changed, update
* our entry accordingly.
*/
r->rt_timer = 0;
if (adj_metric == r->rt_metric)
return;
if (adj_metric == UNREACHABLE) {
del_table_entry(r, 0, DEL_ALL_ROUTES);
r->rt_timer = ROUTE_EXPIRE_TIME;
}
else if (adj_metric < r->rt_metric) {
if (init_children_and_leaves(r, vifi)) {
update_table_entry(r);
}
}
r->rt_metric = adj_metric;
r->rt_flags |= RTF_CHANGED;
routes_changed = TRUE;
}
else if (src == 0 ||
(r->rt_gateway != 0 &&
(adj_metric < r->rt_metric ||
(adj_metric == r->rt_metric &&
(ntohl(src) < ntohl(r->rt_gateway) ||
r->rt_timer >= ROUTE_SWITCH_TIME))))) {
/*
* The report is for an origin we consider reachable; the report
* comes either from one of our own interfaces or from a gateway
* other than the one we have chosen as the best first-hop gateway
* back towards the origin. If the source of the update is one of
* our own interfaces, or if the origin is not a directly-connected
* subnet and the reported metric for that origin is better than
* what our routing entry says, update the entry to use the new
* gateway and metric. We also switch gateways if the reported
* metric is the same as the one in the route entry and the gateway
* associated with the route entry has not been heard from recently,
* or if the metric is the same but the reporting gateway has a lower
* IP address than the gateway associated with the route entry.
* Did you get all that?
*/
if (r->rt_parent != vifi || adj_metric < r->rt_metric) {
/*
* XXX Why do we do this if we are just changing the metric?
*/
r->rt_parent = vifi;
if (init_children_and_leaves(r, vifi)) {
update_table_entry(r);
}
}
r->rt_gateway = src;
r->rt_timer = 0;
r->rt_metric = adj_metric;
r->rt_flags |= RTF_CHANGED;
routes_changed = TRUE;
}
else if (vifi != r->rt_parent) {
/*
* The report came from a vif other than the route's parent vif.
* Update the children and leaf info, if necessary.
*/
if (VIFM_ISSET(vifi, r->rt_children)) {
/*
* Vif is a child vif for this route.
*/
if (metric < r->rt_metric ||
(metric == r->rt_metric &&
ntohl(src) < ntohl(uvifs[vifi].uv_lcl_addr))) {
/*
* Neighbor has lower metric to origin (or has same metric
* and lower IP address) -- it becomes the dominant router,
* and vif is no longer a child for me.
*/
VIFM_CLR(vifi, r->rt_children);
VIFM_CLR(vifi, r->rt_leaves);
r->rt_dominants [vifi] = src;
r->rt_subordinates[vifi] = 0;
r->rt_leaf_timers [vifi] = 0;
update_table_entry(r);
}
else if (metric > UNREACHABLE) { /* "poisoned reverse" */
/*
* Neighbor considers this vif to be on path to route's
* origin; if no subordinate recorded, record this neighbor
* as subordinate and clear the leaf flag.
*/
if (r->rt_subordinates[vifi] == 0) {
VIFM_CLR(vifi, r->rt_leaves);
r->rt_subordinates[vifi] = src;
r->rt_leaf_timers [vifi] = 0;
update_table_entry(r);
}
}
else if (src == r->rt_subordinates[vifi]) {
/*
* Current subordinate no longer considers this vif to be on
* path to route's origin; it is no longer a subordinate
* router, and we set the leaf confirmation timer to give
* us time to hear from other subordinates.
*/
r->rt_subordinates[vifi] = 0;
if (uvifs[vifi].uv_neighbors == NULL ||
uvifs[vifi].uv_neighbors->al_next == NULL) {
VIFM_SET(vifi, r->rt_leaves);
update_table_entry(r);
}
else {
r->rt_leaf_timers [vifi] = LEAF_CONFIRMATION_TIME;
r->rt_flags |= RTF_LEAF_TIMING;
}
}
}
else if (src == r->rt_dominants[vifi] &&
(metric > r->rt_metric ||
(metric == r->rt_metric &&
ntohl(src) > ntohl(uvifs[vifi].uv_lcl_addr)))) {
/*
* Current dominant no longer has a lower metric to origin
* (or same metric and lower IP address); we adopt the vif
* as our own child.
*/
VIFM_SET(vifi, r->rt_children);
r->rt_dominants [vifi] = 0;
if (metric > UNREACHABLE) {
r->rt_subordinates[vifi] = src;
}
else if (uvifs[vifi].uv_neighbors == NULL ||
uvifs[vifi].uv_neighbors->al_next == NULL) {
VIFM_SET(vifi, r->rt_leaves);
}
else {
r->rt_leaf_timers[vifi] = LEAF_CONFIRMATION_TIME;
r->rt_flags |= RTF_LEAF_TIMING;
}
update_table_entry(r);
}
}
}
/*
* Query the kernel to find network interfaces that are multicast-capable
* and install them in the uvifs array.
*/
void
config_vifs_from_kernel(void)
{
struct ifaddrs *ifa, *ifap;
struct uvif *v;
vifi_t vifi;
u_int32_t addr, mask, subnet;
short flags;
if (getifaddrs(&ifap) < 0)
logit(LOG_ERR, errno, "getifaddrs");
for (ifa = ifap; ifa; ifa = ifa->ifa_next) {
/*
* Ignore any interface for an address family other than IP.
*/
if (ifa->ifa_addr->sa_family != AF_INET)
continue;
addr = ((struct sockaddr_in *)ifa->ifa_addr)->sin_addr.s_addr;
/*
* Ignore loopback interfaces and interfaces that do not support
* multicast.
*/
flags = ifa->ifa_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}.
*/
mask = ((struct sockaddr_in *)ifa->ifa_netmask)->sin_addr.s_addr;
subnet = addr & mask;
if (!inet_valid_subnet(subnet, mask) ||
addr == subnet ||
addr == (subnet | ~mask)) {
logit(LOG_WARNING, 0,
"ignoring %s, has invalid address (%s) and/or mask (%s)",
ifa->ifa_name, inet_fmt(addr),
inet_fmt(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) {
logit(LOG_WARNING, 0, "ignoring %s, same subnet as %s",
ifa->ifa_name, v->uv_name);
break;
}
}
if (vifi != numvifs)
continue;
/*
* If there is room in the uvifs array, install this interface.
*/
if (numvifs == MAXVIFS) {
logit(LOG_WARNING, 0, "too many vifs, ignoring %s", ifa->ifa_name);
continue;
}
v = &uvifs[numvifs];
v->uv_flags = 0;
v->uv_metric = DEFAULT_METRIC;
v->uv_rate_limit = DEFAULT_PHY_RATE_LIMIT;
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;
strlcpy(v->uv_name, ifa->ifa_name, sizeof(v->uv_name));
v->uv_groups = NULL;
v->uv_neighbors = NULL;
v->uv_acl = NULL;
v->uv_addrs = NULL;
logit(LOG_INFO,0,"installing %s (%s on subnet %s) as vif #%u - rate=%d",
v->uv_name, inet_fmt(addr),
inet_fmts(subnet, mask),
numvifs, v->uv_rate_limit);
++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;
}
}
freeifaddrs(ifap);
}
/*
* Query the kernel to find network interfaces that are multicast-capable
* and install them in the uvifs array.
*/
void
config_vifs_from_kernel(void)
{
struct ifreq *ifrp, *ifend;
struct uvif *v;
vifi_t vifi;
int n;
u_int32 addr, mask, subnet;
short flags;
int num_ifreq = 32;
ifc.ifc_len = num_ifreq * sizeof(struct ifreq);
ifc.ifc_buf = malloc(ifc.ifc_len);
while (ifc.ifc_buf) {
if (ioctl(udp_socket, SIOCGIFCONF, (char *)&ifc) < 0)
dolog(LOG_ERR, errno, "ioctl SIOCGIFCONF");
/*
* If the buffer was large enough to hold all the addresses
* then break out, otherwise increase the buffer size and
* try again.
*
* The only way to know that we definitely had enough space
* is to know that there was enough space for at least one
* more struct ifreq. ???
*/
if ((num_ifreq * sizeof(struct ifreq)) >=
ifc.ifc_len + sizeof(struct ifreq))
break;
num_ifreq *= 2;
ifc.ifc_len = num_ifreq * sizeof(struct ifreq);
ifc.ifc_buf = realloc(ifc.ifc_buf, ifc.ifc_len);
}
if (ifc.ifc_buf == NULL)
dolog(LOG_ERR, 0, "config_vifs_from_kernel: ran out of memory");
ifrp = (struct ifreq *)ifc.ifc_buf;
ifend = (struct ifreq *)(ifc.ifc_buf + ifc.ifc_len);
/*
* Loop through all of the interfaces.
*/
for (; ifrp < ifend; ifrp = (struct ifreq *)((char *)ifrp + n)) {
struct ifreq ifr;
#ifdef HAVE_SA_LEN
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.
*/
if (ifrp->ifr_addr.sa_family != AF_INET)
continue;
addr = ((struct sockaddr_in *)&ifrp->ifr_addr)->sin_addr.s_addr;
/*
* 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)
dolog(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)
dolog(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)) {
dolog(LOG_WARNING, 0,
"ignoring %s, has invalid address (%s) and/or mask (%s)",
ifr.ifr_name, inet_fmt(addr, s1), inet_fmt(mask, s2));
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 (strcmp(v->uv_name, ifr.ifr_name) == 0) {
dolog(LOG_DEBUG, 0, "skipping %s (%s on subnet %s) (alias for vif#%u?)",
v->uv_name, inet_fmt(addr, s1),
inet_fmts(subnet, mask, s2), vifi);
break;
}
if ((addr & v->uv_subnetmask) == v->uv_subnet ||
(v->uv_subnet & mask) == subnet) {
dolog(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) {
dolog(LOG_WARNING, 0, "too many vifs, ignoring %s", ifr.ifr_name);
continue;
}
v = &uvifs[numvifs];
zero_vif(v, 0);
v->uv_lcl_addr = addr;
v->uv_subnet = subnet;
v->uv_subnetmask = mask;
v->uv_subnetbcast = subnet | ~mask;
strncpy(v->uv_name, ifr.ifr_name, IFNAMSIZ);
v->uv_name[IFNAMSIZ-1] = '\0';
if (flags & IFF_POINTOPOINT)
v->uv_flags |= VIFF_REXMIT_PRUNES;
dolog(LOG_INFO,0,"installing %s (%s on subnet %s) as vif #%u - rate=%d",
v->uv_name, inet_fmt(addr, s1), inet_fmts(subnet, mask, s2),
numvifs, v->uv_rate_limit);
++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;
}
}
}
