[rarun2] Added pseudo tty for listen and connect (#6328)

* [rarun2] added pseudo tty for listen and connect
* Fixed the socket connect error message
* [rarun2] moved pseudo tty under pty option

libr/include/r_socket.h

@@ -205,6 +205,7 @@ typedef struct r_run_profile_t {
 	char *_input;
 	char *_connect;
 	char *_listen;
+	int _pty;
 	int _timeout;
 	int _timeout_sig;
 	int _nice;

libr/socket/run.c

@@ -46,6 +46,8 @@
 #endif
 #endif
 
+#define HAVE_PTY __UNIX__ && !__ANDROID__ && LIBC_HAVE_FORK
+
 R_API RRunProfile *r_run_new(const char *str) {
 	RRunProfile *p = R_NEW (RRunProfile);
 	if (p) {
@@ -221,7 +223,7 @@ static void setASLR(int enabled) {
 }
 
 static int handle_redirection_proc (const char *cmd, bool in, bool out, bool err) {
-#if __UNIX__ && !__ANDROID__ && LIBC_HAVE_FORK
+#if HAVE_PTY
 	// use PTY to redirect I/O because pipes can be problematic in
 	// case of interactive programs.
 	int fdm;
@@ -352,6 +354,7 @@ R_API int r_run_parseline (RRunProfile *p, char *b) {
 	else if (!strcmp (b, "pidfile")) p->_pidfile = strdup (e);
 	else if (!strcmp (b, "connect")) p->_connect = strdup (e);
 	else if (!strcmp (b, "listen")) p->_listen = strdup (e);
+	else if (!strcmp (b, "pty")) p->_pty = parseBool (e);
 	else if (!strcmp (b, "stdio")) {
 		if (e[0] == '!') {
 			p->_stdio = strdup (e);
@@ -448,6 +451,7 @@ R_API const char *r_run_help() {
 	"timeout=3\n"
 	"# connect=localhost:8080\n"
 	"# listen=8080\n"
+	"# pty=false\n"
 	"# fork=true\n"
 	"# bits=32\n"
 	"# pid=0\n"
@@ -475,6 +479,116 @@ R_API const char *r_run_help() {
 	"# nice=5\n";
 }
 
+#if __UNIX__
+static int fd_forward(int in_fd, int out_fd, char **buff) {
+	int size = 0;
+
+	if (ioctl (in_fd, FIONREAD, &size) == -1) {
+		perror ("ioctl");
+		return -1;
+	}
+
+	if (size == 0) { // child process exited or socket is closed
+		return -1;
+	}
+
+	char *new_buff = realloc (*buff, size);
+	if (new_buff == NULL) {
+		eprintf ("Failed to allocate buffer for redirection");
+		return -1;
+	}
+	*buff = new_buff;
+
+	read (in_fd, *buff, size);
+
+	if (write (out_fd, *buff, size) != size) {
+		perror ("write");
+		return -1;
+	}
+
+	return 0;
+}
+#endif
+
+static int redirect_socket_to_stdio(RSocket *sock) {
+	close (0);
+	close (1);
+	close (2);
+
+	dup2 (sock->fd, 0);
+	dup2 (sock->fd, 1);
+	dup2 (sock->fd, 2);
+
+	return 0;
+}
+
+static int redirect_socket_to_pty(RSocket *sock) {
+#if HAVE_PTY
+	// directly duplicating the fds using dup2() creates problems
+	// in case of interactive applications
+	int fdm;
+
+	pid_t child_pid = forkpty (&fdm, NULL, NULL, NULL);
+	if (child_pid == -1) {
+		perror ("forking pty");
+		return -1;
+	}
+
+	if (child_pid == 0) {
+		// child process
+		r_socket_close_fd (sock);
+
+		// disable the echo on slave stdin
+		struct termios t;
+		tcgetattr (0, &t);
+		cfmakeraw (&t);
+		tcsetattr (0, TCSANOW, &t);
+
+		return 0;
+	}
+
+	// parent
+	char *buff = NULL;
+	int sockfd = sock->fd;
+	int max_fd = fdm > sockfd ? fdm : sockfd;
+
+	while (true) {
+		fd_set readfds;
+		FD_ZERO (&readfds);
+		FD_SET (fdm, &readfds);
+		FD_SET (sockfd, &readfds);
+
+		int activity = select (max_fd + 1, &readfds, NULL, NULL, NULL);
+
+		if (activity < 0) {
+			perror ("select error");
+			break;
+		}
+
+		if (FD_ISSET (fdm, &readfds)) {
+			if (fd_forward (fdm, sockfd, &buff) != 0) {
+				break;
+			}
+		}
+
+		if (FD_ISSET (sockfd, &readfds)) {
+			if (fd_forward (sockfd, fdm, &buff) != 0) {
+				break;
+			}
+		}
+	}
+
+	free (buff);
+	close (fdm);
+	r_socket_free (sock);
+
+	_exit (0);
+#else
+	// Fallback to socket to I/O redirection
+	return redirect_socket_to_stdio (sock);
+#endif
+}
+
 R_API int r_run_config_env(RRunProfile *p) {
 	int ret;
 
@@ -521,12 +635,15 @@ R_API int r_run_config_env(RRunProfile *p) {
 				return 1;
 			}
 			eprintf ("connected\n");
-			close (0);
-			close (1);
-			close (2);
-			dup2 (fd->fd, 0);
-			dup2 (fd->fd, 1);
-			dup2 (fd->fd, 2);
+			if (p->_pty) {
+				if (redirect_socket_to_pty (fd) != 0) {
+					eprintf ("socket redirection failed\n");
+					r_socket_free (fd);
+					return 1;
+				}
+			} else {
+				redirect_socket_to_stdio (fd);
+			}
 		} else {
 			eprintf ("Invalid format for connect. missing ':'\n");
 			return 1;
@@ -561,12 +678,16 @@ R_API int r_run_config_env(RRunProfile *p) {
 				if (is_child) {
 					r_socket_close_fd (fd);
 					eprintf ("connected\n");
-					close (0);
-					close (1);
-					close (2);
-					dup2 (child->fd, 0);
-					dup2 (child->fd, 1);
-					dup2 (child->fd, 2);
+					if (p->_pty) {
+						if (redirect_socket_to_pty (child) != 0) {
+							eprintf ("socket redirection failed\n");
+							r_socket_free (child);
+							r_socket_free (fd);
+							return 1;
+						}
+					} else {
+						redirect_socket_to_stdio (child);
+					}
 					break;
 				} else {
 					r_socket_close_fd (child);

libr/socket/socket.c

@@ -253,7 +253,7 @@ R_API bool r_socket_connect (RSocket *s, const char *host, const char *port, int
 		}
 		freeaddrinfo (res);
 		if (!rp) {
-			eprintf ("Could not resolve address '%s'\n", host);
+			eprintf ("Could not resolve address '%s' or failed to connect\n", host);
 			return false;
 		}
 	}

man/rarun2.1

@@ -34,6 +34,8 @@ unset the whole environment
 set no limit the core file size
 .It Ar connect
 connect stdin/stdout/stderr to a socket
+.It Ar pty
+use a pty for connection over socket (with connect/listen)
 .It Ar envfile
 set a file with lines like `var=value` to be used as env
 .It Ar fork