/* add an xroute, verifying some conditions; return 0 if there is no changes */
static int
xroute_add_new_route(unsigned char prefix[16], unsigned char plen,
unsigned short metric, unsigned int ifindex,
int proto, int send_updates)
{
int rc;
if(martian_prefix(prefix, plen))
return 0;
metric = redistribute_filter(prefix, plen, ifindex, proto);
if(metric < INFINITY) {
rc = add_xroute(prefix, plen, metric, ifindex, proto);
if(rc > 0) {
struct babel_route *route;
route = find_installed_route(prefix, plen);
if(route)
uninstall_route(route);
if(send_updates)
send_update(NULL, 0, prefix, plen);
return 1;
}
}
return 0;
}
int
check_xroutes(int send_updates)
{
int i, j, metric, export, change = 0, rc;
struct kernel_route *routes;
struct filter_result filter_result = {0};
int numroutes, numaddresses;
static int maxroutes = 8;
const int maxmaxroutes = 16 * 1024;
debugf("\nChecking kernel routes.\n");
again:
routes = calloc(maxroutes, sizeof(struct kernel_route));
if(routes == NULL)
return -1;
rc = kernel_addresses(0, 0, routes, maxroutes);
if(rc < 0) {
perror("kernel_addresses");
numroutes = 0;
} else {
numroutes = rc;
}
if(numroutes >= maxroutes)
goto resize;
numaddresses = numroutes;
rc = kernel_routes(routes + numroutes, maxroutes - numroutes);
if(rc < 0)
fprintf(stderr, "Couldn't get kernel routes.\n");
else
numroutes += rc;
if(numroutes >= maxroutes)
goto resize;
/* Apply filter to kernel routes (e.g. change the source prefix). */
for(i = numaddresses; i < numroutes; i++) {
filter_result.src_prefix = NULL;
redistribute_filter(routes[i].prefix, routes[i].plen,
routes[i].src_prefix, routes[i].src_plen,
routes[i].ifindex, routes[i].proto,
&filter_result);
if(filter_result.src_prefix) {
memcpy(routes[i].src_prefix, filter_result.src_prefix, 16);
routes[i].src_plen = filter_result.src_plen;
}
}
/* Check for any routes that need to be flushed */
i = 0;
while(i < numxroutes) {
export = 0;
metric = redistribute_filter(xroutes[i].prefix, xroutes[i].plen,
xroutes[i].src_prefix, xroutes[i].src_plen,
xroutes[i].ifindex, xroutes[i].proto,
NULL);
if(metric < INFINITY && metric == xroutes[i].metric) {
for(j = 0; j < numroutes; j++) {
if(xroutes[i].plen == routes[j].plen &&
memcmp(xroutes[i].prefix, routes[j].prefix, 16) == 0 &&
xroutes[i].ifindex == routes[j].ifindex &&
xroutes[i].proto == routes[j].proto) {
export = 1;
break;
}
}
}
