/* Determine whether a given request should be forwarded. */
int
request_redundant(struct interface *ifp,
const unsigned char *prefix, unsigned char plen,
const unsigned char *src_prefix, unsigned char src_plen,
unsigned short seqno, const unsigned char *id)
{
struct resend *request;
request = find_request(prefix, plen, src_prefix, src_plen, NULL);
if(request == NULL || resend_expired(request))
return 0;
if(memcmp(request->id, id, 8) == 0 &&
seqno_compare(request->seqno, seqno) > 0)
return 0;
if(request->ifp != NULL && request->ifp != ifp)
return 0;
if(request->max > 0)
/* Will be resent. */
return 1;
if(timeval_minus_msec(&now, &request->time) <
(ifp ? MIN(ifp->hello_interval, 1000) : 1000))
/* Fairly recent. */
return 1;
return 0;
}
static int
resend_expired(struct resend *resend)
{
switch(resend->kind) {
case RESEND_REQUEST:
return timeval_minus_msec(&now, &resend->time) >= REQUEST_TIMEOUT;
default:
return resend->max <= 0;
}
}
int
main(int argc, char **argv)
{
int i, opt, rc;
int sock;
struct timeval now;
gettime(&now);
inet_pton(AF_INET6, "ff02::1:6", &babel_group);
babel_port = 6696;
srand(now.tv_sec ^ now.tv_usec);
while(1) {
opt = getopt(argc, argv, "p:u:h:c:");
if(opt < 0)
break;
switch(opt) {
case 'p': /* prefix */
if(have_prefix)
goto usage;
rc = inet_pton(AF_INET6, optarg, &myprefix);
if(rc != 1)
goto usage;
have_prefix = 1;
break;
case 'u': /* update interval */
update_interval = atoi(optarg);
if(update_interval <= 0)
goto usage;
break;
case 'h': /* hello interval */
hello_interval = atoi(optarg);
if(hello_interval <= 0)
goto usage;
break;
case 'c': /* link cost */
link_cost = atoi(optarg);
if(link_cost <= 0)
goto usage;
break;
default:
goto usage;
}
}
if(!have_prefix)
fprintf(stderr, "Warning: you didn't ask me to announce a prefix.\n");
if(argc - optind > MAXINTERFACES) {
fprintf(stderr, "Too many interfaces.\n");
exit(1);
}
for(i = 0; i < argc - optind; i++) {
int index;
index = if_nametoindex(argv[optind + i]);
if(index <= 0) {
fprintf(stderr, "Unknown interface %s\n", argv[i]);
exit(1);
}
memset(&interfaces[i], 0, sizeof(interfaces[i]));
interfaces[i].ifindex = index;
interfaces[i].ifname = argv[optind + i];
rc = get_local_address(interfaces[i].ifindex, &interfaces[i].address);
if(rc < 0) {
perror("get_local_address");
fprintf(stderr, "Continuing anyway -- "
"won't perform reachibility detection "
"on interface %s.\n", interfaces[i].ifname);
}
interfaces[i].seqno = rand() & 0xFFFF;
}
numinterfaces = argc - optind;
random_eui64(my_router_id);
myseqno = rand() & 0xFFFF;
sock = babel_socket(babel_port);
if(sock < 0) {
perror("babel_socket");
exit(1);
}
for(i = 0; i < numinterfaces; i++) {
rc = join_group(sock, interfaces[i].ifindex, &babel_group);
if(rc < 0) {
perror("setsockopt(IPV6_JOIN_GROUP)");
exit(1);
}
}
catch_signals(sigexit);
while(!exiting) {
struct sockaddr_in6 sin6;
unsigned char buf[BUF_SIZE];
struct timeval tv, update, zerotv = {0, 0};
fd_set readfds;
int hello_count = 0;
/* Compute when to wake up. */
gettime(&now);
timeval_add_msec(&tv, &last_hello, hello_interval * 700 + rand() % 300);
timeval_add_msec(&update, &last_update,
update_interval * 700 + rand() % 300);
timeval_min(&tv, &update);
if(selected_nexthop_metric < INFINITY) {
int n = find_neighbour(selected_interface, &selected_nexthop, 0);
assert(n >= 0);
timeval_min(&tv, &neighbours[n].timeout);
timeval_min(&tv, &selected_nexthop_timeout);
}
if(timeval_compare(&tv, &now) > 0)
timeval_minus(&tv, &tv, &now);
else
tv = zerotv;
FD_ZERO(&readfds);
FD_SET(sock, &readfds);
rc = select(sock + 1, &readfds, NULL, NULL, &tv);
if(rc < 0 && errno != EINTR) {
perror("select");
nap(1000);
continue;
}
if(rc > 0) {
/* Oh good, a packet. */
socklen_t sin6len = sizeof(sin6);
rc = recvfrom(sock, buf, BUF_SIZE, 0,
(struct sockaddr*)&sin6, &sin6len);
if(rc < 0 || rc >= BUF_SIZE) {
if(rc < 0 && errno != EAGAIN) {
perror("recv");
nap(100);
}
continue;
}
if(sin6.sin6_family != PF_INET6) {
fprintf(stderr, "Received unexpected packet in family %d.\n",
sin6.sin6_family);
nap(100);
continue;
}
i = find_interface(sin6.sin6_scope_id);
if(i < 0) {
fprintf(stderr, "Received packet on unknown interface %d.\n",
sin6.sin6_scope_id);
nap(100);
continue;
}
handle_packet(sock, buf, rc, &interfaces[i], &sin6.sin6_addr);
}
gettime(&now);
if(selected_nexthop_metric < INFINITY) {
int n = find_neighbour(selected_interface, &selected_nexthop, 0);
assert(n >= 0);
if(neighbour_expired(n, &now)) {
/* Expire neighbour. */
flush_default_route();
delete_neighbour(n);
} else if(timeval_compare(&now, &selected_nexthop_timeout) > 0) {
/* Expire route. */
flush_default_route();
}
/* Send a request? */
}
/* Is it time to send hellos? */
if(timeval_minus_msec(&now, &last_hello) > hello_interval * 700) {
for(i = 0; i < numinterfaces; i++)
send_hello(sock, &interfaces[i]);
last_hello = now;
hello_count++;
/* Make an expiry pass every ten hellos. */
if(hello_count >= 10) {
expire_neighbours();
hello_count = 0;
}
}
/* Is it time to send an update? */
if(timeval_minus_msec(&now, &last_update) > update_interval * 700) {
for(i = 0; i < numinterfaces; i++)
send_update(sock, &interfaces[i], 0);
last_update = now;
}
}
/* Send a bunch of retractions. */
for(i = 0; i < numinterfaces; i++)
send_update(sock, &interfaces[i], 1);
flush_default_route();
return 0;
usage:
fprintf(stderr,
"Usage: sbabeld "
"[-p prefix] [-u interval] [-h interval] [-c cost] interface...\n");
return 1;
}
