/*
* 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 hexbuf[SHA1_HEX_LENGTH+1];
UCHAR id[SHA1_BIN_LENGTH];
int rc;
/* Generate the id, e.g. id = sha1(query) */
id_compute( id, query );
log_debug( "KAD: Lookup '%s' as '%s'.", query, str_id( id, hexbuf ) );
dht_lock();
rc = results_collect( id, addr_array, *addr_num );
if( rc < 0 ) {
/* No results item found - no search in progress - start search */
dht_lock();
results_add( id, query );
dht_search( id, 0, gconf->af, dht_callback_func, NULL );
dht_unlock();
*addr_num = 0;
rc = -1;
} else {
*addr_num = rc;
rc = 0;
}
dht_unlock();
return rc;
}
/* 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;
}
}
}
/* Print announced ids we have received */
void kad_debug_storage( int fd ) {
char addrbuf[FULL_ADDSTRLEN+1];
char hexbuf[SHA1_HEX_LENGTH+1];
struct storage *s = storage;
IP addr;
int i, j;
dht_lock();
for( j = 0; s != NULL; ++j ) {
dprintf( fd, "Id: %s\n", str_id(s->id, hexbuf ));
for( i = 0; i < s->numpeers; ++i ) {
struct peer* p = &s->peers[i];
if( p->len == 16 ) {
IP6 *a = (IP6 *) &addr;
a->sin6_family = AF_INET6;
a->sin6_port = htons( p->port );
memcpy( &a->sin6_addr, p->ip, 16 );
} else {
IP4 *a = (IP4 *) &addr;
a->sin_family = AF_INET;
a->sin_port = htons( p->port );
memcpy( &a->sin_addr, p->ip, 4 );
}
dprintf( fd, " Peer: %s\n", str_addr( &addr, addrbuf) );
}
dprintf( fd, " Found %d peers.\n", i );
s = s->next;
}
dprintf( fd, " Found %d stored hashes from received announcements.\n", j );
dht_unlock();
}
/* Print searches */
void kad_debug_searches( int fd ) {
char addrbuf[FULL_ADDSTRLEN+1];
char hexbuf[SHA1_HEX_LENGTH+1];
struct search *s = searches;
int i, j;
dht_lock();
for( j = 0; s != NULL; ++j ) {
dprintf( fd, " Search: %s\n", str_id( s->id, hexbuf ) );
dprintf( fd, " af: %s\n", (s->af == AF_INET) ? "AF_INET" : "AF_INET6" );
dprintf( fd, " port: %hu\n", s->port );
dprintf( fd, " done: %d\n", s->done );
for(i = 0; i < s->numnodes; ++i) {
struct search_node *sn = &s->nodes[i];
dprintf( fd, " Node: %s\n", str_id(sn->id, hexbuf ) );
dprintf( fd, " addr: %s\n", str_addr( &sn->ss, addrbuf ) );
dprintf( fd, " pinged: %d\n", sn->pinged );
dprintf( fd, " replied: %d\n", sn->replied );
dprintf( fd, " acked: %d\n", sn->acked );
}
dprintf( fd, " Found %d nodes.\n", i );
s = s->next;
}
dprintf( fd, " Found %d searches.\n", j );
dht_unlock();
}
/* Print buckets (leaf/finger table) */
void kad_debug_buckets( int fd ) {
char addrbuf[FULL_ADDSTRLEN+1];
char hexbuf[SHA1_HEX_LENGTH+1];
struct bucket *b;
struct node *n;
int i, j;
dht_lock();
b = (gconf->af == AF_INET) ? buckets : buckets6;
for( j = 0; b != NULL; ++j ) {
dprintf( fd, " Bucket: %s\n", str_id( b->first, hexbuf ) );
n = b->nodes;
for( i = 0; n != NULL; ++i ) {
dprintf( fd, " Node: %s\n", str_id( n->id, hexbuf ) );
dprintf( fd, " addr: %s\n", str_addr( &n->ss, addrbuf ) );
dprintf( fd, " pinged: %d\n", n->pinged );
n = n->next;
}
dprintf( fd, " Found %d nodes.\n", i );
b = b->next;
}
dprintf( fd, " Found %d buckets.\n", j );
dht_unlock();
}
int kad_export_nodes( IP addr_array[], size_t *num ) {
IP4 addr4[64];
IP6 addr6[64];
int num4;
int num6;
int i, count;
num6 = N_ELEMS( addr6 );
num4 = N_ELEMS( addr4 );
dht_lock();
dht_get_nodes( addr4, &num4, addr6, &num6 );
dht_unlock();
count = 0;
for( i = 0; i < num6 && count < *num; ++i, ++count ) {
memcpy( &addr_array[i], &addr6[i], sizeof(IP6) );
}
for( i = 0; i < num4 && count < *num; ++i, ++count ) {
memcpy( &addr_array[i], &addr4[i], sizeof(IP4) );
}
/* Store number of nodes we have actually found */
*num = count;
return 0;
}
/*
* Lookup the address of the node that has the given id.
* The port refers to the kad instance.
*/
int kad_lookup_node( const char query[], IP *addr_return ) {
UCHAR id[SHA1_BIN_LENGTH];
struct search *sr;
int i, rc;
/* That is the node id to lookup */
id_compute( id, query );
dht_lock();
rc = -1;
sr = searches;
while( sr ) {
if( sr->af == gconf->af && id_equal( sr->id, id ) ) {
for( i = 0; i < sr->numnodes; ++i ) {
if( id_equal( sr->nodes[i].id, id ) ) {
memcpy( addr_return, &sr->nodes[i].ss, sizeof(IP) );
rc = 0;
goto done;
}
}
break;
}
sr = sr->next;
}
done:;
dht_unlock();
return rc;
}
/* Print announced ids we have received */
void kad_debug_storage( int fd ) {
char addrbuf[FULL_ADDSTRLEN+1];
char hexbuf[SHA1_HEX_LENGTH+1];
struct storage *s;
struct peer* p;
IP addr;
int i, j;
dht_lock();
s = storage;
for( j = 0; s != NULL; ++j ) {
dprintf( fd, " ID: %s\n", str_id(s->id, hexbuf ));
for( i = 0; i < s->numpeers; ++i ) {
p = &s->peers[i];
to_addr( &addr, &p->ip, p->len, htons( p->port ) );
dprintf( fd, " Peer: %s\n", str_addr( &addr, addrbuf) );
}
dprintf( fd, " Found %d peers.\n", i );
s = s->next;
}
dprintf( fd, " Found %d stored hashes from received announcements.\n", j );
dht_unlock();
}
/*
* Lookup the address of the node that has the given id.
* The port refers to the kad instance.
*/
int kad_lookup_node( const char query[], IP *addr_return ) {
UCHAR id[SHA1_BIN_LENGTH];
struct search *sr;
int i, rc;
if( strlen( query ) != SHA1_HEX_LENGTH || !str_isHex( query, SHA1_HEX_LENGTH ) ) {
return -1;
}
bytes_from_hex( id, query, SHA1_HEX_LENGTH );
dht_lock();
rc = 1;
sr = searches;
while( sr ) {
if( sr->af == gconf->af && id_equal( sr->id, id ) ) {
for( i = 0; i < sr->numnodes; ++i ) {
if( id_equal( sr->nodes[i].id, id ) ) {
memcpy( addr_return, &sr->nodes[i].ss, sizeof(IP) );
rc = 0;
goto done;
}
}
break;
}
sr = sr->next;
}
done:;
dht_unlock();
return rc;
}
int kad_blacklist( const IP* addr ) {
dht_lock();
blacklist_node( NULL, (struct sockaddr *) addr, sizeof(IP) );
dht_unlock();
return 0;
}
int kad_ping( const IP* addr ) {
int rc;
dht_lock();
rc = dht_ping_node( (struct sockaddr *)addr, addr_len( addr ) );
dht_unlock();
return (rc < 0) ? -1 : 0;
}
/*
* 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;
}
/*
* Find nodes that are near the given id and announce to them
* that this node can satisfy the given id on the given port
*/
int kad_announce( const UCHAR *id, int port ) {
if( port < 1 || port > 65535 ) {
return -1;
}
dht_lock();
dht_search( id, port, gconf->af, dht_callback_func, NULL );
dht_unlock();
return 0;
}
void kad_debug_blacklist( int fd ) {
char addrbuf[FULL_ADDSTRLEN+1];
int i;
dht_lock();
for( i = 0; i < (next_blacklisted % DHT_MAX_BLACKLISTED); i++ ) {
dprintf( fd, " %s\n", str_addr( &blacklist[i], addrbuf ) );
}
dprintf( fd, " Found %d blacklisted addresses.\n", i );
dht_unlock();
}
/* Export known nodes; the maximum is 200 nodes */
int kad_export_nodes( IP addr_array[], size_t *num ) {
IP4 *addr4;
IP6 *addr6;
int num4;
int num6;
int i;
if( gconf->af == AF_INET6 ) {
num6 = MIN(*num, 200);
addr6 = calloc( num6, sizeof(IP6) );
num4 = 0;
addr4 = NULL;
} else {
num6 = 0;
addr6 = NULL;
num4 = MIN(*num, 200);
addr4 = calloc( num4, sizeof(IP4) );
}
dht_lock();
dht_get_nodes( addr4, &num4, addr6, &num6 );
dht_unlock();
if( gconf->af == AF_INET6 ) {
for( i = 0; i < num6; ++i ) {
memcpy( &addr_array[i], &addr6[i], sizeof(IP6) );
}
free( addr6 );
} else {
for( i = 0; i < num4; ++i ) {
memcpy( &addr_array[i], &addr4[i], sizeof(IP4) );
}
free( addr4 );
}
/* Store number of nodes we have actually found */
*num = i;
return 0;
}
