Various changes. SEGFAULT fixed.

src/db/database.h

@@ -36,7 +36,7 @@ int db_add_peer (dbConnection *, uint8_t [20], db_peerEntry*);
  * lst: pointer to an array whose maximum size is passed to sZ.
  * sZ returns the amount of peers returned.
  */
-int db_load_peers (dbConnection *, uint8_t [20], db_peerEntry **lst, int *sZ);
+int db_load_peers (dbConnection *, uint8_t [20], db_peerEntry *lst, int *sZ);
 
 int db_get_stats (dbConnection *, uint8_t [20], uint32_t *seeders, uint32_t *leechers, uint32_t *completed);
 
@@ -45,4 +45,6 @@ int db_get_stats (dbConnection *, uint8_t [20], uint32_t *seeders, uint32_t *lee
  */
 int db_cleanup (dbConnection *);
 
+int db_remove_peer (dbConnection *, uint8_t hash [20], db_peerEntry *);
+
 #endif /* DATABASE_H_ */

src/db/driver_sqlite.c

@@ -14,7 +14,7 @@ struct dbConnection
 
 static const char hexadecimal[] = "0123456789abcdef";
 
-static void _to_hex_str (const uint8_t *hash, char *data)
+void _to_hex_str (const uint8_t *hash, char *data)
 {
 	int i;
 	for (i = 0;i < 20;i++)
@@ -34,7 +34,7 @@ static int _db_make_torrent_table (sqlite3 *db, char *hash)
 	strcat(sql, hash);
 	strcat (sql, "' (");
 
-	strcat (sql, "peer_id blob(20) UNIQUE,"
+	strcat (sql, "peer_id blob(20),"
 			"ip blob(4),"
 			"port blob(2),"
 			"uploaded blob(8)," // uint64
@@ -42,12 +42,12 @@ static int _db_make_torrent_table (sqlite3 *db, char *hash)
 			"left blob(8),"
 			"last_seen INT DEFAULT 0");
 
-	strcat(sql, ")");
+	strcat(sql, ", CONSTRAINT c1 UNIQUE (ip,port) ON CONFLICT REPLACE)");
 
 	// create table.
 	char *err_msg;
 	int r = sqlite3_exec(db, sql, NULL, NULL, &err_msg);
-//	printf("E:%s\n", err_msg);
+	printf("E:%s\n", err_msg);
 
 	return r;
 }
@@ -131,7 +131,7 @@ int db_add_peer (dbConnection *db, uint8_t info_hash[20], db_peerEntry *pE)
 	return r;
 }
 
-int db_load_peers (dbConnection *db, uint8_t info_hash[20], db_peerEntry **lst, int *sZ)
+int db_load_peers (dbConnection *db, uint8_t info_hash[20], db_peerEntry *lst, int *sZ)
 {
 	char sql [1000];
 	sql[0] = '\0';
@@ -150,16 +150,16 @@ int db_load_peers (dbConnection *db, uint8_t info_hash[20], db_peerEntry **lst,
 	int i = 0;
 	int r;
 
-	while (1)
+	while (*sZ > i)
 	{
 		r = sqlite3_step(stmt);
 		if (r == SQLITE_ROW)
 		{
-			const void *ip = sqlite3_column_blob (stmt, 0);
+			const char *ip = (const char*)sqlite3_column_blob (stmt, 0);
-			const void *port = sqlite3_column_blob (stmt, 1);
+			const char *port = (const char*)sqlite3_column_blob (stmt, 1);
 
-			memcpy(&lst[i]->ip, ip, 4);
+			memcpy(&lst[i].ip, ip, 4);
-			memcpy(&lst[i]->port, port, 2);
+			memcpy(&lst[i].port, port, 2);
 
 			i++;
 		}
@@ -167,6 +167,8 @@ int db_load_peers (dbConnection *db, uint8_t info_hash[20], db_peerEntry **lst,
 			break;
 	}
 
+	printf("%d Clients Dumped.\n", i);
+
 	sqlite3_finalize(stmt);
 
 	*sZ = i;
@@ -286,3 +288,29 @@ int db_cleanup (dbConnection *db)
 
 	return 0;
 }
+
+int db_remove_peer (dbConnection *db, uint8_t hash[20], db_peerEntry *pE)
+{
+	char sql [1000];
+	char xHash [50];
+
+	_to_hex_str (hash, xHash);
+
+	strcpy (sql, "DELETE FROM 't");
+	strcat (sql, xHash);
+	strcat (sql, "' WHERE ip=? AND port=? AND peer_id=?");
+
+	sqlite3_stmt *stmt;
+
+	sqlite3_prepare (db->db, sql, -1, &stmt, NULL);
+
+	sqlite3_bind_blob(stmt, 0, (const void*)&pE->ip, 4, NULL);
+	sqlite3_bind_blob(stmt, 1, (const void*)&pE->port, 2, NULL);
+	sqlite3_bind_blob(stmt, 2, (const void*)pE->peer_id, 20, NULL);
+
+	sqlite3_step(stmt);
+
+	sqlite3_finalize(stmt);
+
+	return 0;
+}

src/main.c

@@ -18,17 +18,42 @@
 #include <math.h>
 #include <time.h>
 
-int main(void)
+int main(int argc, char *argv[])
 {
 	printf("UDP BitTorrentTracker %s\t\tCopyright: (C) 2012 Naim Abda.\n\n", VERSION);
 
+#ifdef linux
+	if (argc > 1)
+	{
+		if (strcmp(argv[1], "d") == 0)
+		{
+			pid_t pid;
+			pid = fork ();
+
+			if (pid < 0)
+			{
+				printf ("Failed to start daemon.\n");
+				exit (EXIT_FAILURE);
+			}
+			if (pid > 0)
+			{
+				printf("Daemon Started; pid=%d.\n", pid);
+				fclose (stdin);
+				fclose (stdout);
+				fclose (stderr);
+				exit (EXIT_SUCCESS);
+			}
+		}
+	}
+#endif
+
 #ifdef WIN32
 	WSADATA wsadata;
 	WSAStartup(MAKEWORD(2, 2), &wsadata);
 #endif
 
 	udpServerInstance usi;
-	UDPTracker_init(&usi, 6969, 1);
+	UDPTracker_init(&usi, 6969, 5);
 
 	if (UDPTracker_start(&usi) != 0)
 	{

src/multiplatform.h

@@ -18,6 +18,7 @@
 #define INVALID_SOCKET 0
 #define SOCKET_ERROR -1
 #define DWORD uint64_t
+#define closesocket(s) close(s)
 typedef struct hostent HOSTENT;
 typedef struct sockaddr SOCKADDR;
 typedef struct sockaddr_in SOCKADDR_IN;

src/udpTracker.c

@@ -145,6 +145,30 @@ static int _handle_connection (udpServerInstance *usi, SOCKADDR_IN *remote, char
 	return 0;
 }
 
+static int _is_good_peer (uint32_t ip, uint16_t port)
+{
+	SOCKADDR_IN addr;
+	addr.sin_family = AF_INET;
+#ifdef WIN32
+	addr.sin_addr.S_un.S_addr = htonl( ip );
+#elif defined (linux)
+	addr.sin_addr.s_addr = htonl( ip );
+#endif
+	addr.sin_port = htons (port);
+
+	SOCKET cli = socket (AF_INET, SOCK_STREAM, IPPROTO_TCP);
+	if (cli == INVALID_SOCKET)
+		return 1;
+	if (connect(cli, (SOCKADDR*)&addr, sizeof(SOCKADDR_IN)) == SOCKET_ERROR)
+	{
+		closesocket (cli);
+		return 1;
+	}
+	printf ("Client Verified.\n");
+	closesocket (cli);
+	return 0;
+}
+
 static int _handle_announce (udpServerInstance *usi, SOCKADDR_IN *remote, char *data)
 {
 	AnnounceRequest *req = (AnnounceRequest*)data;
@@ -162,20 +186,36 @@ static int _handle_announce (udpServerInstance *usi, SOCKADDR_IN *remote, char *
 	req->uploaded = m_hton64 (req->uploaded);
 	req->num_want = m_hton32 (req->num_want);
 	req->left = m_hton64 (req->left);
+	if (req->ip_address == 0) // default
+	{
+		req->ip_address = m_hton32 (remote->sin_addr.s_addr);
+	}
 
+//	if (_is_good_peer(req->ip_address, req->port) != 0)
+//	{
+//		_send_error (usi, remote, req->transaction_id, "Couldn't verify your client.");
+//		return 0;
+//	}
 
 	// load peers
 	int q = 30;
 	if (req->num_want >= 1)
 		q = min (q, req->num_want);
 
-	db_peerEntry *peers = malloc (sizeof(db_peerEntry) * q);
+	db_peerEntry *peers = NULL;
-
-	db_load_peers(usi->conn, req->info_hash, &peers, &q);
-//	printf("%d peers found.\n", q);
-
 	int bSize = 20; // header is 20 bytes
-	bSize += (6 * q); // + 6 bytes per peer.
+
+	if (req->event == 3) // stopped; they don't need anymore peers!
+	{
+		q = 0; // don't need any peers!
+	}
+	else
+	{
+		peers = malloc (sizeof(db_peerEntry) * q);
+		db_load_peers(usi->conn, req->info_hash, peers, &q);
+	}
+
+	bSize += (6 * q); // + 6 bytes per peer (ip->4, port->2).
 
 	uint32_t seeders, leechers, completed;
 	db_get_stats (usi->conn, req->info_hash, &seeders, &leechers, &completed);
@@ -206,24 +246,29 @@ static int _handle_announce (udpServerInstance *usi, SOCKADDR_IN *remote, char *
 
 //		printf("%u.%u.%u.%u:%u\n", buff[20 + x], buff[21 + x], buff[22 + x], buff[23 + x], peers[i].port);
 	}
-	free (peers);
+
+	if (peers != NULL)
+		free (peers);
+
 	sendto(usi->sock, (char*)buff, bSize, 0, (SOCKADDR*)remote, sizeof(SOCKADDR_IN));
 
+
 	// Add peer to list:
 	db_peerEntry pE;
 	pE.downloaded = req->downloaded;
 	pE.uploaded = req->uploaded;
 	pE.left = req->left;
 	pE.peer_id = req->peer_id;
-	if (req->ip_address == 0) // default
+	pE.ip = req->ip_address;
-	{
-		pE.ip = m_hton32 (remote->sin_addr.s_addr);
-	}
-	else
-	{
-		pE.ip = req->ip_address;
-	}
 	pE.port = req->port;
+
+	if (req->event == 3) // stopped
+	{
+		// just remove client from swarm, and return empty peer list...
+		db_remove_peer(usi->conn, req->info_hash, &pE);
+		return 0;
+	}
+
 	db_add_peer(usi->conn, req->info_hash,  &pE);
 
 	return 0;
@@ -233,7 +278,14 @@ static int _handle_scrape (udpServerInstance *usi, SOCKADDR_IN *remote, char *da
 {
 	ScrapeRequest *sR = (ScrapeRequest*)data;
 
-	_send_error (usi, remote, sR->transaction_id, "Scrape wasn't implemented yet!");
+//	_send_error (usi, remote, sR->transaction_id, "Scrape wasn't implemented yet!");
+
+	ScrapeResponse resp;
+	resp.resp_part = NULL;
+	resp.action = 2;
+	resp.transaction_id = sR->transaction_id;
+
+	sendto (usi->sock, (const char*)&resp, 8, 0, (SOCKADDR*)remote, sizeof(SOCKADDR_IN));
 
 	return 0;
 }

src/udpTracker.h

@@ -59,8 +59,20 @@ struct udp_scrape_request
 	uint64_t connection_id;
 	uint32_t action;
 	uint32_t transaction_id;
+	struct reqD {
+		uint8_t info_hash [20];
+	} *req_part;
+};
 
-	uint8_t *torrent_list_data;
+struct udp_scrape_response
+{
+	uint32_t action;
+	uint32_t transaction_id;
+	struct respD {
+		uint32_t seeders;
+		uint32_t completed;
+		uint32_t leechers;
+	} *resp_part;
 };
 
 struct udp_error_response
@@ -89,6 +101,7 @@ typedef struct udp_connection_response ConnectionResponse;
 typedef struct udp_announce_request AnnounceRequest;
 typedef struct udp_announce_response AnnounceResponse;
 typedef struct udp_scrape_request ScrapeRequest;
+typedef struct udp_scrape_response ScrapeResponse;
 typedef struct udp_error_response ErrorResponse;
 
 void UDPTracker_init (udpServerInstance *, uint16_t port, uint8_t threads);