/* Handle incoming packets and pass them to the DHT code */
void dht_handler( int rc, int sock ) {
UCHAR buf[1500];
IP from;
socklen_t fromlen;
time_t time_wait = 0;
if( rc > 0 ) {
/* Check which socket received the data */
fromlen = sizeof(from);
rc = recvfrom( sock, buf, sizeof(buf) - 1, 0, (struct sockaddr*) &from, &fromlen );
if( rc <= 0 || rc >= sizeof(buf) ) {
return;
}
/* The DHT code expects the message to be null-terminated. */
buf[rc] = '\0';
/* Handle incoming data */
dht_lock();
rc = dht_periodic( buf, rc, (struct sockaddr*) &from, fromlen, &time_wait, dht_callback_func, NULL );
dht_unlock();
if( rc < 0 && errno != EINTR ) {
if( rc == EINVAL || rc == EFAULT ) {
log_err( "DHT: Error calling dht_periodic." );
}
g_dht_maintenance = time_now_sec() + 1;
} else {
g_dht_maintenance = time_now_sec() + time_wait;
}
} else if( g_dht_maintenance <= time_now_sec() ) {
/* Do a maintenance call */
dht_lock();
rc = dht_periodic( NULL, 0, NULL, 0, &time_wait, dht_callback_func, NULL );
dht_unlock();
/* Wait for the next maintenance call */
g_dht_maintenance = time_now_sec() + time_wait;
log_debug( "DHT: Next maintenance call in %u seconds.", (unsigned int) time_wait );
} else {
rc = 0;
}
if( rc < 0 ) {
if( errno == EINTR ) {
return;
} else if( rc == EINVAL || rc == EFAULT ) {
log_err( "DHT: Error using select: %s", strerror( errno ) );
return;
} else {
g_dht_maintenance = time_now_sec() + 1;
}
}
}
/* handle 'GET /announce?foo.p2p' */
void handle_announce( char *reply_buf, char *params ) {
if( kad_announce( params, 0, (time_now_sec() + 60) ) >= 0 ) {
sprintf( reply_buf , "done\n" );
} else {
sprintf( reply_buf , "failed\n" );
}
}
/*
* Lookup known nodes that are nearest to the given id.
*/
int kad_lookup_value( const char _query[], IP addr_array[], size_t *addr_num ) {
char query[QUERY_MAX_SIZE];
struct results_t *results;
int is_new;
int rc;
if( query_sanitize( query, sizeof(query), _query ) != 0 ) {
return -2;
}
log_debug( "KAD: Lookup string: %s", query );
dht_lock();
/* Find existing or create new item */
results = results_add( query, &is_new );
if( results && is_new ) {
/* Search own announced values */
kad_lookup_local_values( results );
}
if( results == NULL ) {
/* Failed to create a new search */
rc = -1;
} else if( results->done ) {
/*
* The search exists already but has finished. Restart the search when
* no results have been found or more than half of the searches lifetime
* has expired.
*/
if( results_entries_count( results ) == 0 ||
(time_now_sec() - results->start_time) > (MAX_SEARCH_LIFETIME / 2)
) {
/* Mark search as in progress */
results_done( results, 0 );
/* Start another search for this id */
dht_search( results->id, 0, gconf->af, dht_callback_func, NULL );
}
rc = 2;
} else if( is_new ) {
/* Start a new DHT search */
dht_search( results->id, 0, gconf->af, dht_callback_func, NULL );
rc = 1;
} else {
/* Search is still running */
rc = 0;
}
/* Collect addresses to be returned */
*addr_num = results_collect( results, addr_array, *addr_num );
dht_unlock();
return rc;
}
int cmd_exec( REPLY *r, int argc, char **argv ) {
char addrbuf[FULL_ADDSTRLEN+1];
time_t lifetime;
int minutes;
IP addrs[16];
int port;
int count;
static struct value_t *value;
char *p;
int rc = 0;
if( argc == 0 ) {
/* Print usage */
r_printf( r, cmd_usage );
if( r->allow_debug ) {
r_printf( r, cmd_usage_debug );
}
rc = 1;
} else if( match( argv[0], "import" ) && argc == 2 ) {
rc = cmd_import( r, argv[1] );
#if 0
} else if( match( argv[0], "lookup_node" ) && argc == 2 ) {
/* Check searches for node */
rc = kad_lookup_node( argv[1], &addrs[0] );
if( rc == 0 ) {
r_printf( r, "%s\n", str_addr( &addrs[0], addrbuf ) );
} else if( rc == 1 ) {
r_printf( r ,"No search found.\n" );
rc = 1;
} else if( rc == 2 ) {
r_printf( r ,"Invalid id format. 20 digit hex string expected.\n" );
rc = 1;
} else {
rc = 1;
}
#endif
} else if( match( argv[0], "lookup" ) && argc == 2 ) {
size_t num = N_ELEMS(addrs);
size_t i;
/* Check searches for node */
rc = kad_lookup_value( argv[1], addrs, &num );
if( rc >= 0 && num > 0 ) {
for( i = 0; i < num; ++i ) {
r_printf( r, "%s\n", str_addr( &addrs[i], addrbuf ) );
}
} else if( rc < 0 ) {
r_printf( r ,"Some error occured.\n" );
rc = 1;
} else if( rc == 0 ) {
r_printf( r ,"Search in progress.\n" );
rc = 1;
} else {
r_printf( r ,"Search started.\n" );
rc = 1;
}
} else if( match( argv[0], "status" ) && argc == 1 ) {
/* Print node id and statistics */
cmd_print_status( r );
} else if( match( argv[0], "announce" ) && (argc == 1 || argc == 2 || argc == 3) ) {
if( argc == 1 ) {
/* Announce all values; does not update value.refreshed */
count = 0;
value = values_get();
while( value ) {
kad_announce_once( value->id, value->port );
count++;
value = value->next;
}
r_printf( r ,"%d announcements started.\n", count );
rc = 0;
goto end;
} else if( argc == 2 ) {
minutes = 0;
lifetime = 0;
} else if( argc == 3 ) {
minutes = atoi( argv[2] );
if( minutes < 0 ) {
minutes = 0;
lifetime = LONG_MAX;
} else {
/* Round up to multiple of 30 minutes */
minutes = (30 * (minutes/30 + 1));
lifetime = (time_now_sec() + (minutes * 60));
}
} else {
/* Make compilers happy */
exit( 1 );
}
int is_random_port = 0;
/* Find <id>:<port> delimiter */
p = strchr( argv[1], ':' );
if( p ) {
*p = '\0';
port = port_parse( p + 1, -1 );
} else {
/* A valid port will be choosen inside kad_announce() */
port = 0;
is_random_port = 1;
}
if( kad_announce( argv[1], port, lifetime ) >= 0 ) {
#ifdef FWD
if( !is_random_port ) {
forwardings_add( port, lifetime);
}
#endif
if( lifetime == 0 ) {
r_printf( r ,"Start single announcement now.\n" );
} else if( lifetime == LONG_MAX ) {
r_printf( r ,"Start regular announcements for the entire run time (%sport %d).\n", (is_random_port ? "random " : ""), port );
} else {
r_printf( r ,"Start regular announcements for %d minutes (%sport %d).\n", minutes, (is_random_port ? "random " : ""), port );
}
} else {
r_printf( r ,"Invalid port or query too long.\n" );
rc = 1;
}
} else if( match( argv[0], "blacklist" ) && argc == 2 ) {
rc = cmd_blacklist( r, argv[1] );
} else if( match( argv[0], "export" ) && argc == 1 ) {
rc = cmd_export( r );
} else if( match( argv[0], "list" ) && argc == 2 && r->allow_debug ) {
if( gconf->is_daemon == 1 ) {
r_printf( r ,"The 'list' command is not available while KadNode runs as daemon.\n" );
rc = 1;
goto end;
} else if( match( argv[1], "blacklist" ) ) {
kad_debug_blacklist( STDOUT_FILENO );
rc = 0;
} else if( match( argv[1], "buckets" ) ) {
kad_debug_buckets( STDOUT_FILENO );
rc = 0;
} else if( match( argv[1], "constants" ) ) {
kad_debug_constants( STDOUT_FILENO );
rc = 0;
#ifdef FWD
} else if( match( argv[1], "forwardings" ) ) {
forwardings_debug( STDOUT_FILENO );
rc = 0;
#endif
#ifdef AUTH
} else if( match( argv[1], "pkeys" ) ) {
auth_debug_pkeys( STDOUT_FILENO );
rc = 0;
} else if( match( argv[1], "skeys" ) ) {
auth_debug_skeys( STDOUT_FILENO );
rc = 0;
#endif
} else if( match( argv[1], "results" ) ) {
results_debug( STDOUT_FILENO );
rc = 0;
} else if( match( argv[1], "searches" ) ) {
kad_debug_searches( STDOUT_FILENO );
rc = 0;
} else if( match( argv[1], "storage" ) ) {
kad_debug_storage( STDOUT_FILENO );
rc = 0;
} else if( match( argv[1], "values" ) ) {
values_debug( STDOUT_FILENO );
rc = 0;
} else {
dprintf( STDERR_FILENO, "Unknown argument.\n" );
rc = 1;
}
r_printf( r ,"\nOutput send to console.\n" );
} else {
/* print usage */
r_printf( r, cmd_usage );
if( r->allow_debug ) {
r_printf( r, cmd_usage_debug );
}
rc = 1;
}
end:
;
return rc;
}
void handle_mcast( int rc, int sock_recv ) {
char addrbuf[FULL_ADDSTRLEN+1];
char buf[512];
IP c_addr;
socklen_t addrlen;
int rc_recv;
if( g_mcast_time <= time_now_sec() ) {
if( kad_count_nodes( 0 ) == 0 ) {
/* Join multicast group if possible */
if( g_mcast_registered == 0 && multicast_set_groups( sock_recv, &g_lpd_addr, gconf->dht_ifname, 1 ) == 0 ) {
log_info( "LPD: No peers known. Joined multicast group." );
g_mcast_registered = 1;
}
if( g_mcast_registered == 1 ) {
log_info( "LPD: Send multicast message to find nodes." );
/* Create message */
snprintf(
buf, sizeof(buf),
msg_fmt, str_addr( &g_lpd_addr, addrbuf ),
atoi( gconf->dht_port ), g_infohash
);
mcast_send_packets( buf, gconf->dht_ifname );
}
}
/* Cap number of received packets to 10 per minute */
g_packet_limit = 5 * PACKET_LIMIT_MAX;
/* Try again in ~5 minutes */
g_mcast_time = time_add_min( 5 );
}
if( rc <= 0 ) {
return;
}
/* Reveice multicast ping */
addrlen = sizeof(IP);
rc_recv = recvfrom( sock_recv, buf, sizeof(buf), 0, (struct sockaddr*) &c_addr, (socklen_t*) &addrlen );
if( rc_recv < 0 ) {
log_warn( "LPD: Cannot receive multicast message: %s", strerror( errno ) );
return;
}
if( g_packet_limit < 0 ) {
/* Too much traffic - leave multicast group for now */
if( g_mcast_registered == 1 && multicast_set_groups( sock_recv, &g_lpd_addr, gconf->dht_ifname, 0 ) == 0 ) {
log_warn( "LPD: Too much traffic. Left multicast group." );
g_mcast_registered = 0;
}
return;
} else {
g_packet_limit--;
}
if( rc_recv >= sizeof(buf) ) {
return;
} else {
buf[rc_recv] = '\0';
}
int port = parse_packet( buf );
if( port > 0 ) {
port_set( &c_addr, port );
log_debug( "LPD: Ping lonely peer at %s", str_addr( &c_addr, addrbuf ) );
kad_ping( &c_addr );
} else {
log_debug( "LPD: Received invalid packet on multicast group." );
}
}
time_t time_add_hour( unsigned int hours ) {
return time_now_sec() + (60 * 60 * hours);
}
time_t time_add_min( unsigned int minutes ) {
return time_now_sec() + (60 * minutes);
}
