/** Initialize the firewall rules
*/
int
fw_init(void)
{
int result = 0;
int new_fw_state;
t_client *client = NULL;
if (!init_icmp_socket()) {
return 0;
}
debug(LOG_INFO, "Initializing Firewall");
result = iptables_fw_init();
if (restart_orig_pid) {
debug(LOG_INFO, "Restoring firewall rules for clients inherited from parent");
LOCK_CLIENT_LIST();
client = client_get_first_client();
while (client) {
new_fw_state = client->fw_connection_state;
client->fw_connection_state = FW_MARK_NONE;
fw_allow(client, new_fw_state);
client = client->next;
}
UNLOCK_CLIENT_LIST();
}
return result;
}
int
main(int argc, char **argv) {
int opt, sockfd;
int background_flag = 1;
int if_index = 0;
fd_set rfds;
struct timeval timeout;
while ((opt = getopt(argc, argv, "fi:")) != -1) {
switch (opt) {
case 'f': /* foreground */
background_flag = 0;
break;
case 'i':
if_index = if_nametoindex(optarg);
break;
default:
usage();
exit(EXIT_FAILURE);
}
}
openlog("routeradv_listend", LOG_CONS|LOG_PERROR, LOG_DAEMON);
sockfd = init_icmp_socket(if_index);
if (sockfd < 0)
return 1;
if (background_flag)
daemonize(sockfd);
init_routers();
for (;;) {
FD_ZERO(&rfds);
FD_SET(sockfd, &rfds);
memset(&timeout, 0, sizeof(timeout));
timeout.tv_sec = next_timeout();
if (select(sockfd + 1, &rfds, NULL, NULL, &timeout) < 0) {
/* select() might have failed because we received a signal, so we need to check */
if (errno != EINTR) {
syslog(LOG_CRIT, "select: %s", strerror(errno));
return 1;
}
/* handle signals */
continue; /* our file descriptor sets are undefined, so select again */
}
if (FD_ISSET (sockfd, &rfds))
recv_icmp_msg(sockfd);
handle_routers();
}
return 0;
}
int binary_search(SOCKADDR_IN *dst, int timeout, RouteInfo *rinfo)
{
int ttl=0, high=32, low=1, iterations=MAX_ITERATIONS, retries = 0;
ULONG start_test_timestamp = GetTickCount();
SOCKET sr;
sr = init_icmp_socket();
rinfo->cnt_packet_waste=0;
strcpy(rinfo->path, UNDEFINED_PATH);
rinfo->resp_ttl=UNDEFINED_TTL;
rinfo->hopdist = UNDEFINED_TTL;
// counting iterations is just to make sure
// no one is fooling us into an infinite loop
while (iterations--)
{
if (!ttl) ttl = STARTING_TTL; // this is the first time ttl is set.
// since most sites are closer than 32, we start with it.
else ttl = (high+low)/2;
switch (udping(sr, dst, 0, timeout, &rinfo->rtt,
&rinfo->cnt_packet_waste, (unsigned short)ttl))
{
case -1: // too short
low = ttl+1;
break;
case 1: // exact or too long
if (high == ttl || (ttl+low)/2 == ttl) // exact!
{
rinfo->time_waste_on_test = GetTickCount()-start_test_timestamp;
rinfo->hopdist = ttl;
closesocket(sr);
return 1;
}
high = ttl; // too long...
break;
case 0: // timeout
if (ttl < high && retries != NUMBER_OF_RETRIES) // if possible, let's give it another chance.
{
high--;
retries++;
break;
}
rinfo->time_waste_on_test = GetTickCount()-start_test_timestamp;
closesocket(sr);
return 0;
}
}
rinfo->time_waste_on_test = GetTickCount()-start_test_timestamp;
closesocket(sr);
return 0;
}
int copied_ttl(SOCKADDR_IN *dst, unsigned int timeout, RouteInfo *rinfo)
{
SOCKET sr;
SOCKADDR_IN from;
int icmp_type, delta, is_packet_recieved, copiedttl;
unsigned short seq_sent, seq_resp;
ULONG start_test_timestamp = GetTickCount();
sr = init_icmp_socket();
strcpy(rinfo->path, UNDEFINED_PATH);
rinfo->resp_ttl = UNDEFINED_TTL;
rinfo->cnt_packet_waste = 0;
seq_sent = INITIAL_SEQ;
while(GetTickCount()-start_test_timestamp < timeout*1000)
{
ULONG start_packet_timestamp = GetTickCount();
send_udp_packet(dst, MAX_TTL, seq_sent);
rinfo->cnt_packet_waste++;
is_packet_recieved = wait_for_icmp(sr, &seq_resp, &icmp_type, &from, &copiedttl, timeout);
delta = GetTickCount()-start_packet_timestamp;
if (!is_packet_recieved) //we got no reply
{
// fprintf(stderr, "%3d Request timed out\t", MAX_TTL);
break;
}
if(seq_sent == seq_resp) //check if this is our ICMP packet
{
if (icmp_type == ICMP_DEST_UNREACH)
{
rinfo->time_waste_on_test = GetTickCount() - start_test_timestamp;
rinfo->rtt = delta;
rinfo->hopdist = MAX_TTL+1-copiedttl;
closesocket(sr);
return 1;
}
}
//it was not a response to our packet. send it again
}
closesocket(sr);
return 0;
}
unsigned int __stdcall ping_thread_entry(void *data)
#endif
{
PingThreadData *pdata = (PingThreadData *)data;
int maxfd, ret;
fd_set all_rset, rset;
struct timeval to;
I3ServerList *list = pdata->list;
char *url = pdata->url;
uint64_t *ping_start_time = pdata->ping_start_time;
int num_pings;
I3ServerListNode *next_to_ping;
uint64_t last_ping_time, curr_time;
uint64_t last_add_new_i3servers, last_update_serverlist;
FD_ZERO(&all_rset);
FD_ZERO(&rset);
/* socket init */
#ifdef ICMP_PING
if (init_icmp_socket(&ping_sock) == -1)
abort();
#else
if (init_udp_socket(&ping_sock) == -1)
abort();
#endif
FD_SET(ping_sock, &all_rset);
maxfd = ping_sock + 1;
/* initial populate the list of i3 servers */
update_i3_server_list(url, list, &next_to_ping);
/* determine coordinates */
init_coordinates(list);
/* add some close-by servers from the list based on coordinates */
change_ping_list(list, &next_to_ping, 1);
/* eternal loop */
last_ping_time = last_add_new_i3servers = last_update_serverlist = wall_time();
set_status(ping_start_time, last_ping_time);
for (;;) {
rset = all_rset;
to.tv_sec = 0; to.tv_usec = 10000;
if ((ret = select(maxfd, &rset, NULL, NULL, &to)) < 0) {
if (errno == EINTR)
continue;
else {
perror("select");
abort();
}
}
/* message received on icmp socket */
if (FD_ISSET(ping_sock, &rset)) {
uint32_t addr; uint16_t port, seq; uint64_t rtt;
#ifdef ICMP_PING
if (recv_echo_reply(ping_sock, &addr, &seq, &rtt)) {
#else
if (recv_i3_echo_reply(ping_sock, &addr, &port, &seq, &rtt)) {
#endif
update_ping_information(list, addr, seq, rtt);
}
}
/* need to ping */
curr_time = wall_time();
if (list->num_ping_list > 0) {
char status = get_status(ping_start_time, curr_time);
num_pings = (curr_time - last_ping_time)/
(period_ping[status]/list->num_ping_list);
if (num_pings > 0) {
if (NULL == next_to_ping) {
I3_PRINT_DEBUG0(I3_DEBUG_LEVEL_MINIMAL,
"No servers to ping. Aborting\n");
}
send_npings(ping_sock, list, &next_to_ping, num_pings);
last_ping_time = curr_time;
}
}
/* change the list of i3 servers */
if (curr_time - last_add_new_i3servers >
period_pick_new_server[get_status(ping_start_time, curr_time)]) {
/* testing just the best server */
uint32_t best_addr; uint16_t best_port; uint64_t best_rtt;
struct in_addr ia;
int required_k = 1;
int ret = get_top_k(list, required_k, &best_addr, &best_port, &best_rtt);
if (ret != required_k) {
// We couldn't find the request k top nodes.
I3_PRINT_INFO0 (
I3_INFO_LEVEL_WARNING,
"I3 Ping Thread: Unable to obtain top k nodes.\n"
);
// Dilip: Feb 20, 2006. I don't think the following works.
// TODO: Start
// We set the last_add_new_servers to fool the thread
// to wait for some time before trying again to get
// the top k nodes.
//last_add_new_i3servers = curr_time;
// TODO: End
// Sleep for some time before trying again.
# if defined (_WIN32)
Sleep ( 25 ); // 25 milliseconds
# else
usleep(25 * 1000); // 25 milliseconds
# endif
continue;
}
ia.s_addr = htonl(best_addr);
I3_PRINT_DEBUG3(I3_INFO_LEVEL_MINIMAL,
"Best node: %s:%d with RTT %Ld\n",
inet_ntoa(ia), best_port, best_rtt
);
I3_PRINT_DEBUG0(I3_DEBUG_LEVEL_VERBOSE, "Adding new servers to list\n");
change_ping_list(list, &next_to_ping, 0);
last_add_new_i3servers = curr_time;
}
/* update (wget) i3 server list */
if (curr_time - last_update_serverlist > PERIOD_SERVERLIST_WGET) {
I3_PRINT_DEBUG0( I3_DEBUG_LEVEL_VERBOSE,
"Updating server list from server\n");
update_i3_server_list(url, list, &next_to_ping);
last_update_serverlist = curr_time;
}
}
#ifndef _WIN32
pthread_exit(0);
#endif
return 0;
}
/* To determine the coordinates of the local node initially
* Ping a subset of nodes and determine coordinates */
void init_coordinates(I3ServerList *list)
{
int n = MIN(NUM_LANDMARKS_COORDINATE, list->num_newservers + list->num_ping_list);
I3ServerListNode *node = list->list, *temp_node;
uint64_t start_time = wall_time();
Coordinates_RTT coord_rtt[NUM_LANDMARKS_COORDINATE];
int num_landmarks = 0; int started_full_list = 0;
struct in_addr ia;
nw_skt_t tmp_ping_sock;
#ifdef ICMP_PING
if (init_icmp_socket(&tmp_ping_sock) == -1)
abort();
#else
if (init_udp_socket(&tmp_ping_sock) == -1)
abort();
#endif
// wait for responses and accumulate
// cut and pasted from below
while ((wall_time() - start_time < COORD_INIT_PING_WAIT_TIME) &&
(num_landmarks < n)) {
fd_set rset;
struct timeval to;
int ret;
FD_ZERO(&rset);
if (!node && !started_full_list) {
node = list-> full_list;
started_full_list = 1;
}
if (node) {
ia.s_addr = htonl(node->addr);
I3_PRINT_DEBUG1(I3_DEBUG_LEVEL_VERBOSE,
"Sending ICMP echo request to %s\n", inet_ntoa(ia));
#ifdef ICMP_PING
send_echo_request(tmp_ping_sock, node->addr, 0);
#else
i3_echo_request(tmp_ping_sock, node->addr, node->port, 0);
#endif
node = node->next_list;
}
FD_SET(tmp_ping_sock, &rset);
to.tv_sec = 0; to.tv_usec = 200000ULL;
if ((ret = select(tmp_ping_sock+1, &rset, NULL, NULL, &to)) < 0) {
int err = nw_error();
if (err == EINTR)
continue;
else {
perror("select");
abort();
}
}
// message received on icmp socket
if (FD_ISSET(tmp_ping_sock, &rset)) {
uint32_t addr; uint16_t port, seq; uint64_t rtt;
#ifdef ICMP_PING
if (recv_echo_reply(tmp_ping_sock, &addr, &seq, &rtt)) {
#else
if (recv_i3_echo_reply(tmp_ping_sock, &addr, &port, &seq, &rtt)) {
#endif
temp_node = lookup_i3server(list, addr);
assert(NULL != temp_node);
coord_rtt[num_landmarks].coord = temp_node->coord;
coord_rtt[num_landmarks].rtt = rtt;
num_landmarks++;
ia.s_addr = htonl(addr);
I3_PRINT_DEBUG4(I3_DEBUG_LEVEL_VERBOSE,
"Node: %s Coordinate: %.1f:%.1f RTT: %Ld\n",
inet_ntoa(ia), temp_node->coord.latitude,
temp_node->coord.longitude, rtt);
}
}
}
nw_close(tmp_ping_sock);
// compute own coordinate
compute_coordinates(num_landmarks, coord_rtt);
}
/* Update the coordinates of a node using ping information */
void update_coordinate(I3ServerList *list, I3ServerListNode *next_to_ping)
{
Coordinates_RTT coord_rtt[NUM_LANDMARKS_COORDINATE];
int count, num_landmarks = 0;
I3ServerListNode *node;
// n1 and n2: number of landmarks from ping_list and rest in
// proportion to the number of nodes in those lists
int i, n = MIN(NUM_LANDMARKS_COORDINATE,
list->num_newservers + list->num_ping_list);
int n1 = ((float)list->num_ping_list/
(list->num_newservers + list->num_ping_list)) * n;
int n2 = n-n1;
// add from ping list
count = 0;
for (i = 0, node = list->list;
i < list->num_ping_list, count < n1;
node = node->next_list, ++i) {
if (node->n > 0) {
coord_rtt[count].rtt = get_rtt_node(node);
coord_rtt[count].coord = node->coord;
count++;
}
}
num_landmarks = count;
// add from rest
count = 0;
for (i = 0, node = list->full_list;
i < list->num_newservers, count < n2;
node = node->next_list, ++i) {
if (node->n > 0) {
coord_rtt[num_landmarks + count].rtt = get_rtt_node(node);
coord_rtt[num_landmarks + count].coord = node->coord;
count++;
}
}
num_landmarks += count;
// recompute coordinates
compute_coordinates(num_landmarks, coord_rtt);
// repopulate ping list afresh
change_ping_list(list, &next_to_ping, 1);
}