void
server_loop2(Authctxt *authctxt)
{
	fd_set *readset = NULL, *writeset = NULL;
	int rekeying = 0, max_fd, nalloc = 0;

	debug("Entering interactive session for SSH2.");

	mysignal(SIGCHLD, sigchld_handler);
	child_terminated = 0;
	connection_in = packet_get_connection_in();
	connection_out = packet_get_connection_out();

	notify_setup();

	max_fd = MAX(connection_in, connection_out);
	max_fd = MAX(max_fd, notify_pipe[0]);

	xxx_authctxt = authctxt;

	server_init_dispatch();

	for (;;) {
		process_buffered_input_packets();

		rekeying = (xxx_kex != NULL && !xxx_kex->done);

		if (!rekeying && packet_not_very_much_data_to_write())
			channel_output_poll();
		wait_until_can_do_something(&readset, &writeset, &max_fd,
		    &nalloc, 0);

		collect_children();
		if (!rekeying) {
			channel_after_select(readset, writeset);
			if (packet_need_rekeying()) {
				debug("need rekeying");
				xxx_kex->done = 0;
				kex_send_kexinit(xxx_kex);
			}
		}
		process_input(readset);
		if (connection_closed)
			break;
		process_output(writeset);
	}
	collect_children();

	if (readset)
		xfree(readset);
	if (writeset)
		xfree(writeset);

	/* free all channels, no more reads and writes */
	channel_free_all();

	/* free remaining sessions, e.g. remove wtmp entries */
	session_destroy_all(NULL);
}
void
server_loop2(Authctxt *authctxt)
{
	fd_set *readset = NULL, *writeset = NULL;
	int rekeying = 0, max_fd;
	u_int nalloc = 0;
	u_int64_t rekey_timeout_ms = 0;

	debug("Entering interactive session for SSH2.");

	mysignal(SIGCHLD, sigchld_handler);
	child_terminated = 0;
	connection_in = packet_get_connection_in();
	connection_out = packet_get_connection_out();

	if (!use_privsep) {
		signal(SIGTERM, sigterm_handler);
		signal(SIGINT, sigterm_handler);
		signal(SIGQUIT, sigterm_handler);
	}

	notify_setup();

	max_fd = MAX(connection_in, connection_out);
	max_fd = MAX(max_fd, notify_pipe[0]);

	server_init_dispatch();
	for (;;) {
		process_buffered_input_packets();

		rekeying = (xxx_kex != NULL && !xxx_kex->done);

		if (!rekeying && packet_not_very_much_data_to_write())
			channel_output_poll();
		if (options.rekey_interval > 0 && compat20 && !rekeying)
			rekey_timeout_ms = packet_get_rekey_timeout() * 1000;
		else
			rekey_timeout_ms = 0;

		wait_until_can_do_something(&readset, &writeset, &max_fd,
		    &nalloc, rekey_timeout_ms);

		if (received_sigterm) {
			logit("Exiting on signal %d", (int)received_sigterm);
			/* Clean up sessions, utmp, etc. */
			cleanup_exit(255);
		}

		collect_children();
		if (!rekeying) {
			channel_after_select(readset, writeset);
			if (packet_need_rekeying()) {
				debug("need rekeying");
				xxx_kex->done = 0;
				kex_send_kexinit(xxx_kex);
			}
		}
		process_input(readset);
		if (connection_closed)
			break;
		process_output(writeset);
	}
	collect_children();

	free(readset);
	free(writeset);

	/* free all channels, no more reads and writes */
	channel_free_all();

	/* free remaining sessions, e.g. remove wtmp entries */
	session_destroy_all(NULL);
}
/*
 * Performs the interactive session.  This handles data transmission between
 * the client and the program.  Note that the notion of stdin, stdout, and
 * stderr in this function is sort of reversed: this function writes to
 * stdin (of the child program), and reads from stdout and stderr (of the
 * child program).
 */
void
server_loop(pid_t pid, int fdin_arg, int fdout_arg, int fderr_arg)
{
	fd_set *readset = NULL, *writeset = NULL;
	int max_fd = 0;
	u_int nalloc = 0;
	int wait_status;	/* Status returned by wait(). */
	pid_t wait_pid;		/* pid returned by wait(). */
	int waiting_termination = 0;	/* Have displayed waiting close message. */
	u_int64_t max_time_milliseconds;
	u_int previous_stdout_buffer_bytes;
	u_int stdout_buffer_bytes;
	int type;

	debug("Entering interactive session.");

	/* Initialize the SIGCHLD kludge. */
	child_terminated = 0;
	mysignal(SIGCHLD, sigchld_handler);

	if (!use_privsep) {
		signal(SIGTERM, sigterm_handler);
		signal(SIGINT, sigterm_handler);
		signal(SIGQUIT, sigterm_handler);
	}

	/* Initialize our global variables. */
	fdin = fdin_arg;
	fdout = fdout_arg;
	fderr = fderr_arg;

	/* nonblocking IO */
	set_nonblock(fdin);
	set_nonblock(fdout);
	/* we don't have stderr for interactive terminal sessions, see below */
	if (fderr != -1)
		set_nonblock(fderr);

	if (!(datafellows & SSH_BUG_IGNOREMSG) && isatty(fdin))
		fdin_is_tty = 1;

	connection_in = packet_get_connection_in();
	connection_out = packet_get_connection_out();

	notify_setup();

	previous_stdout_buffer_bytes = 0;

	/* Set approximate I/O buffer size. */
	if (packet_is_interactive())
		buffer_high = 4096;
	else
		buffer_high = 64 * 1024;

#if 0
	/* Initialize max_fd to the maximum of the known file descriptors. */
	max_fd = MAX(connection_in, connection_out);
	max_fd = MAX(max_fd, fdin);
	max_fd = MAX(max_fd, fdout);
	if (fderr != -1)
		max_fd = MAX(max_fd, fderr);
#endif

	/* Initialize Initialize buffers. */
	buffer_init(&stdin_buffer);
	buffer_init(&stdout_buffer);
	buffer_init(&stderr_buffer);

	/*
	 * If we have no separate fderr (which is the case when we have a pty
	 * - there we cannot make difference between data sent to stdout and
	 * stderr), indicate that we have seen an EOF from stderr.  This way
	 * we don't need to check the descriptor everywhere.
	 */
	if (fderr == -1)
		fderr_eof = 1;

	server_init_dispatch();

	/* Main loop of the server for the interactive session mode. */
	for (;;) {

		/* Process buffered packets from the client. */
		process_buffered_input_packets();

		/*
		 * If we have received eof, and there is no more pending
		 * input data, cause a real eof by closing fdin.
		 */
		if (stdin_eof && fdin != -1 && buffer_len(&stdin_buffer) == 0) {
			if (fdin != fdout)
				close(fdin);
			else
				shutdown(fdin, SHUT_WR); /* We will no longer send. */
			fdin = -1;
		}
		/* Make packets from buffered stderr data to send to the client. */
		make_packets_from_stderr_data();

		/*
		 * Make packets from buffered stdout data to send to the
		 * client. If there is very little to send, this arranges to
		 * not send them now, but to wait a short while to see if we
		 * are getting more data. This is necessary, as some systems
		 * wake up readers from a pty after each separate character.
		 */
		max_time_milliseconds = 0;
		stdout_buffer_bytes = buffer_len(&stdout_buffer);
		if (stdout_buffer_bytes != 0 && stdout_buffer_bytes < 256 &&
		    stdout_buffer_bytes != previous_stdout_buffer_bytes) {
			/* try again after a while */
			max_time_milliseconds = 10;
		} else {
			/* Send it now. */
			make_packets_from_stdout_data();
		}
		previous_stdout_buffer_bytes = buffer_len(&stdout_buffer);

		/* Send channel data to the client. */
		if (packet_not_very_much_data_to_write())
			channel_output_poll();

		/*
		 * Bail out of the loop if the program has closed its output
		 * descriptors, and we have no more data to send to the
		 * client, and there is no pending buffered data.
		 */
		if (fdout_eof && fderr_eof && !packet_have_data_to_write() &&
		    buffer_len(&stdout_buffer) == 0 && buffer_len(&stderr_buffer) == 0) {
			if (!channel_still_open())
				break;
			if (!waiting_termination) {
				const char *s = "Waiting for forwarded connections to terminate... (press ~& to background)\r\n";
				char *cp;
				waiting_termination = 1;
				buffer_append(&stderr_buffer, s, strlen(s));

				/* Display list of open channels. */
				cp = channel_open_message();
				buffer_append(&stderr_buffer, cp, strlen(cp));
				free(cp);
			}
		}
		max_fd = MAX(connection_in, connection_out);
		max_fd = MAX(max_fd, fdin);
		max_fd = MAX(max_fd, fdout);
		max_fd = MAX(max_fd, fderr);
		max_fd = MAX(max_fd, notify_pipe[0]);

		/* Sleep in select() until we can do something. */
		wait_until_can_do_something(&readset, &writeset, &max_fd,
		    &nalloc, max_time_milliseconds);

		if (received_sigterm) {
			logit("Exiting on signal %d", (int)received_sigterm);
			/* Clean up sessions, utmp, etc. */
			cleanup_exit(255);
		}

		/* Process any channel events. */
		channel_after_select(readset, writeset);

		/* Process input from the client and from program stdout/stderr. */
		process_input(readset);

		/* Process output to the client and to program stdin. */
		process_output(writeset);
	}
	free(readset);
	free(writeset);

	/* Cleanup and termination code. */

	/* Wait until all output has been sent to the client. */
	drain_output();

	debug("End of interactive session; stdin %ld, stdout (read %ld, sent %ld), stderr %ld bytes.",
	    stdin_bytes, fdout_bytes, stdout_bytes, stderr_bytes);

	/* Free and clear the buffers. */
	buffer_free(&stdin_buffer);
	buffer_free(&stdout_buffer);
	buffer_free(&stderr_buffer);

	/* Close the file descriptors. */
	if (fdout != -1)
		close(fdout);
	fdout = -1;
	fdout_eof = 1;
	if (fderr != -1)
		close(fderr);
	fderr = -1;
	fderr_eof = 1;
	if (fdin != -1)
		close(fdin);
	fdin = -1;

	channel_free_all();

	/* We no longer want our SIGCHLD handler to be called. */
	mysignal(SIGCHLD, SIG_DFL);

	while ((wait_pid = waitpid(-1, &wait_status, 0)) < 0)
		if (errno != EINTR)
			packet_disconnect("wait: %.100s", strerror(errno));
	if (wait_pid != pid)
		error("Strange, wait returned pid %ld, expected %ld",
		    (long)wait_pid, (long)pid);

	/* Check if it exited normally. */
	if (WIFEXITED(wait_status)) {
		/* Yes, normal exit.  Get exit status and send it to the client. */
		debug("Command exited with status %d.", WEXITSTATUS(wait_status));
		packet_start(SSH_SMSG_EXITSTATUS);
		packet_put_int(WEXITSTATUS(wait_status));
		packet_send();
		packet_write_wait();

		/*
		 * Wait for exit confirmation.  Note that there might be
		 * other packets coming before it; however, the program has
		 * already died so we just ignore them.  The client is
		 * supposed to respond with the confirmation when it receives
		 * the exit status.
		 */
		do {
			type = packet_read();
		}
		while (type != SSH_CMSG_EXIT_CONFIRMATION);

		debug("Received exit confirmation.");
		return;
	}
	/* Check if the program terminated due to a signal. */
	if (WIFSIGNALED(wait_status))
		packet_disconnect("Command terminated on signal %d.",
				  WTERMSIG(wait_status));

	/* Some weird exit cause.  Just exit. */
	packet_disconnect("wait returned status %04x.", wait_status);
	/* NOTREACHED */
}
Exemple #4
0
void
server_loop2(Authctxt *authctxt)
{
    fd_set *readset = NULL, *writeset = NULL;
    int rekeying = 0, max_fd, nalloc = 0;
    double start_time, total_time;

    debug("Entering interactive session for SSH2.");
    start_time = get_current_time();

    mysignal(SIGCHLD, sigchld_handler);
    child_terminated = 0;
    connection_in = packet_get_connection_in();
    connection_out = packet_get_connection_out();

    if (!use_privsep) {
        signal(SIGTERM, sigterm_handler);
        signal(SIGINT, sigterm_handler);
        signal(SIGQUIT, sigterm_handler);
    }

    notify_setup();

    max_fd = MAX(connection_in, connection_out);
    max_fd = MAX(max_fd, notify_pipe[0]);

    server_init_dispatch();

    for (;;) {
        process_buffered_input_packets();

        rekeying = (xxx_kex != NULL && !xxx_kex->done);

        if (!rekeying && packet_not_very_much_data_to_write())
            channel_output_poll();
        wait_until_can_do_something(&readset, &writeset, &max_fd,
                                    &nalloc, 0);

        if (received_sigterm) {
            logit("Exiting on signal %d", received_sigterm);
            /* Clean up sessions, utmp, etc. */
            cleanup_exit(255);
        }

        collect_children();
        if (!rekeying) {
            channel_after_select(readset, writeset);
            if (packet_need_rekeying()) {
                debug("need rekeying");
                xxx_kex->done = 0;
                kex_send_kexinit(xxx_kex);
            }
        }
        process_input(readset);
        if (connection_closed)
            break;
        process_output(writeset);
    }
    collect_children();

    if (readset)
        xfree(readset);
    if (writeset)
        xfree(writeset);

    /* free all channels, no more reads and writes */
    channel_free_all();

    /* free remaining sessions, e.g. remove wtmp entries */
    session_destroy_all(NULL);
    total_time = get_current_time() - start_time;
    logit("SSH: Server;LType: Throughput;Remote: %s-%d;IN: %lu;OUT: %lu;Duration: %.1f;tPut_in: %.1f;tPut_out: %.1f",
          get_remote_ipaddr(), get_remote_port(),
          stdin_bytes, fdout_bytes, total_time, stdin_bytes / total_time,
          fdout_bytes / total_time);
}