Add passive mode (only for localhost) and fix random thread crashes

src/client.cpp

@@ -8,6 +8,7 @@
 #include <arpa/inet.h>
 #include <sys/stat.h>
 #include <time.h>
+#include <thread>
 
 #include "server.h"
 #include "filer.cpp"
@@ -25,6 +26,7 @@ public:
 	 *  2 - Waiting for data
 	 */
 	int state = 0;
+	std::thread thread;
 
 	Client(int &_sock) {
 		control_sock = _sock;
@@ -37,7 +39,7 @@ public:
 			return -1;
 		} else if (state > 0) {
 			if (cmd == "SYST") {
-				submit(215, "UNIX");
+				submit(215, "UNIX Type: L8");
 			} else if (cmd == "PWD") {
 				submit(257, "'"+filer->cwd.string()+"'");
 			} else if (cmd == "CWD") {
@@ -69,7 +71,76 @@ public:
 				sscanf(argstr.c_str(), "%c", &(filer->type));
 				submit(226, "OK");
 			} else if (cmd == "PASV") {
-				submit(502, "Command not implemented");
+				if ((data_fd = socket(AF_INET, SOCK_STREAM, 0)) < 0) {
+					perror("pasv socket() failed");
+					return -1;
+				}
+				
+				if (setsockopt(data_fd, SOL_SOCKET, SO_REUSEADDR | SO_REUSEPORT, (char *)&opt, sizeof(opt)) < 0) {
+					perror("pasv setsockopt() failed");
+					close(data_fd);
+					return -1;
+				}
+				
+				uint16_t dataport;
+				uint8_t netaddr[4];
+				uint8_t netport[2];
+				socklen_t datalen = sizeof(data_address);
+				
+				data_address.sin_family = AF_INET;
+				data_address.sin_addr.s_addr = INADDR_ANY;
+				data_address.sin_port = 0;
+				
+				if (bind(data_fd, (struct sockaddr *)&data_address, sizeof(data_address)) < 0) {
+					perror("pasv bind() failed");
+					close(data_fd);
+					return -1;
+				}
+				
+				if (listen(data_fd, 3) < 0) {
+					perror("pasv listen() failed");
+					close(data_fd);
+					return -1;
+				}
+				
+				if (getsockname(data_fd, (struct sockaddr *)&data_address, &datalen) == 0) {
+					//memcpy(&netaddr[0], &data_address.sin_addr, 4);
+					netaddr[0] = 127;
+					netaddr[1] = netaddr[2] = 0;
+					netaddr[3] = 1;
+					dataport = ntohs(data_address.sin_port);
+					memcpy(&netport[0], &dataport, 2);
+					printf("[i] D(%i) PASV initialized: %u.%u.%u.%u:%u\n", data_fd, netaddr[0], netaddr[1], netaddr[2], netaddr[3], dataport);
+				} else {
+					perror("pasv getpeername() failed");
+					close(data_fd);
+					return -1;
+				}
+				
+				char* pasvok;
+				asprintf(
+					&pasvok,
+					"Entering Passive Mode (%u,%u,%u,%u,%u,%u)",
+					netaddr[0],
+					netaddr[1],
+					netaddr[2],
+					netaddr[3],
+					netport[1],
+					netport[0]
+				);
+				
+				submit(227, std::string(pasvok));
+				free(pasvok);
+				
+				if ((data_sock = accept(data_fd, NULL, NULL)) >= 0) {
+					printf("[i] D(%i) PASV accepted: %i\n", data_fd, data_sock);
+					state = 2;
+					//submit(200, "OK");
+				} else {
+					perror("accept() failed");
+					submit(425, "Unknown Error");
+					data_close();
+				}
 			} else if (cmd == "PORT") {
 				data_sock = socket(AF_INET, SOCK_STREAM, 0);
 				
@@ -79,16 +150,15 @@ public:
 				sscanf(argstr.c_str(), "%d,%d,%d,%d,%d,%d", &act_ip[0], &act_ip[1], &act_ip[2], &act_ip[3], (int*)&act_port[0], (int*)&act_port[1]);
 				sprintf(ip_decimal, "%d.%d.%d.%d", act_ip[0], act_ip[1], act_ip[2], act_ip[3]);
 				port_dec = act_port[0]*256+act_port[1];
-				printf("[d] D(%i) Initialized data transport: %s:%d\n", control_sock, ip_decimal, port_dec);
+				printf("[d] D(%i) PORT initialized: %s:%d\n", control_sock, ip_decimal, port_dec);
 				
 				data_address.sin_family = AF_INET;
 				data_address.sin_addr.s_addr = inet_addr(ip_decimal);
 				data_address.sin_port = htons(port_dec);
 						
 				if (connect(data_sock, (struct sockaddr *)&data_address, sizeof(data_address)) != 0) {
-					close(data_sock);
-					data_sock = 0;
 					submit(425, "Unknown Error");
+					data_close();
 				} else {
 					state = 2;
 					submit(200, "OK");
@@ -152,9 +222,7 @@ public:
 					}
 					submit(226, "OK");
 				}
-				if (data_close() != 0) {
-					printf("[!] Data Sock returned %i instead of 0! Not closed!!!\n", data_sock);
-				}
+				data_close();
 			} else {
 				submit(502, "Command not implemented");
 			}
@@ -205,17 +273,22 @@ public:
 	}
 	
 	int data_close() {
+		if (data_sock <= 0) return 0;
 		printf("[d] D(%i) Closing...\n", data_sock);
 		close(data_sock);
-		data_sock = 0;
+		data_sock = -1;
+		close(data_fd);
+		data_fd = -1;
 		state = 1;
-		return data_sock; // Should be 0 if successful.
+		return 0;
 	}
 	
 private:
 	std::string name;
 	Filer* filer = new Filer();
+	const int opt = 1;
 	
+	int data_fd;
 	int data_sock;
 	struct sockaddr_in data_address;
 };