コード例 #1
0
ファイル: sshnetcat.c プロジェクト: chrisdew/node-libssh
static void forwarding(ssh_session session){
    ssh_channel channel;
    int r;
    channel=channel_new(session);
    r=channel_open_forward(channel,desthost,atoi(port),"localhost",22);
    if(r<0) {
        printf("error forwarding port : %s\n",ssh_get_error(session));
        return;
    }
    select_loop(session,channel);
}
コード例 #2
0
ファイル: remmina_ssh.c プロジェクト: B0SB05/Remmina
static gpointer
remmina_ssh_tunnel_main_thread_proc (gpointer data)
{
	RemminaSSHTunnel *tunnel = (RemminaSSHTunnel*) data;
	gchar *ptr;
	ssize_t len = 0, lenw = 0;
	fd_set set;
	struct timeval timeout;
	GTimeVal t1, t2;
	glong diff;
	ssh_channel channel = NULL;
	gboolean first = TRUE;
	gboolean disconnected;
	gint sock;
	gint maxfd;
	gint i;
	gint ret;
	struct sockaddr_in sin;

	g_get_current_time (&t1);
	t2 = t1;

	switch (tunnel->tunnel_type)
	{
		case REMMINA_SSH_TUNNEL_OPEN:
		/* Accept a local connection */
		sock = accept (tunnel->server_sock, NULL, NULL);
		if (sock < 0)
		{
			REMMINA_SSH (tunnel)->error = g_strdup ("Failed to accept local socket");
			tunnel->thread = 0;
			return NULL;
		}

		if ((channel = channel_new (tunnel->ssh.session)) == NULL)
		{
			close (sock);
			remmina_ssh_set_error (REMMINA_SSH (tunnel), "Failed to createt channel : %s");
			tunnel->thread = 0;
			return NULL;
		}
		/* Request the SSH server to connect to the destination */
		if (channel_open_forward (channel, tunnel->dest, tunnel->port, "127.0.0.1", 0) != SSH_OK)
		{
			close (sock);
			channel_close (channel);
			channel_free (channel);
			remmina_ssh_set_error (REMMINA_SSH (tunnel), _("Failed to connect to the SSH tunnel destination: %s"));
			tunnel->thread = 0;
			return NULL;
		}
		remmina_ssh_tunnel_add_channel (tunnel, channel, sock);
		break;

		case REMMINA_SSH_TUNNEL_X11:
		if ((tunnel->x11_channel = channel_new (tunnel->ssh.session)) == NULL)
		{
			remmina_ssh_set_error (REMMINA_SSH (tunnel), "Failed to create channel : %s");
			tunnel->thread = 0;
			return NULL;
		}
		if (!remmina_public_get_xauth_cookie (tunnel->localdisplay, &ptr))
		{
			remmina_ssh_set_application_error (REMMINA_SSH (tunnel), "%s", ptr);
			g_free(ptr);
			tunnel->thread = 0;
			return NULL;
		}
		if (channel_open_session (tunnel->x11_channel) ||
				channel_request_x11 (tunnel->x11_channel, TRUE, NULL, ptr,
						gdk_screen_get_number (gdk_screen_get_default ())))
		{
			g_free(ptr);
			remmina_ssh_set_error (REMMINA_SSH (tunnel), "Failed to open channel : %s");
			tunnel->thread = 0;
			return NULL;
		}
		g_free(ptr);
		if (channel_request_exec (tunnel->x11_channel, tunnel->dest))
		{
			ptr = g_strdup_printf(_("Failed to execute %s on SSH server : %%s"), tunnel->dest);
			remmina_ssh_set_error (REMMINA_SSH (tunnel), ptr);
			g_free(ptr);
			tunnel->thread = 0;
			return NULL;
		}

		if (tunnel->init_func &&
				! (*tunnel->init_func) (tunnel, tunnel->callback_data))
		{
			if (tunnel->disconnect_func)
			{
				(*tunnel->disconnect_func) (tunnel, tunnel->callback_data);
			}
			tunnel->thread = 0;
			return NULL;
		}

		break;

		case REMMINA_SSH_TUNNEL_XPORT:
		/* Detect the next available port starting from 6010 on the server */
		for (i = 10; i <= MAX_X_DISPLAY_NUMBER; i++)
		{
			if (channel_forward_listen (REMMINA_SSH (tunnel)->session,
							(tunnel->bindlocalhost ? "localhost" : NULL), 6000 + i, NULL))
			{
				continue;
			}
			else
			{
				tunnel->remotedisplay = i;
				break;
			}
		}
		if (tunnel->remotedisplay < 1)
		{
			remmina_ssh_set_error (REMMINA_SSH (tunnel), _("Failed to request port forwarding : %s"));
			if (tunnel->disconnect_func)
			{
				(*tunnel->disconnect_func) (tunnel, tunnel->callback_data);
			}
			tunnel->thread = 0;
			return NULL;
		}

		if (tunnel->init_func &&
				! (*tunnel->init_func) (tunnel, tunnel->callback_data))
		{
			if (tunnel->disconnect_func)
			{
				(*tunnel->disconnect_func) (tunnel, tunnel->callback_data);
			}
			tunnel->thread = 0;
			return NULL;
		}

		break;

		case REMMINA_SSH_TUNNEL_REVERSE:
		if (channel_forward_listen (REMMINA_SSH (tunnel)->session, NULL, tunnel->port, NULL))
		{
			remmina_ssh_set_error (REMMINA_SSH (tunnel), _("Failed to request port forwarding : %s"));
			if (tunnel->disconnect_func)
			{
				(*tunnel->disconnect_func) (tunnel, tunnel->callback_data);
			}
			tunnel->thread = 0;
			return NULL;
		}

		if (tunnel->init_func &&
				! (*tunnel->init_func) (tunnel, tunnel->callback_data))
		{
			if (tunnel->disconnect_func)
			{
				(*tunnel->disconnect_func) (tunnel, tunnel->callback_data);
			}
			tunnel->thread = 0;
			return NULL;
		}

		break;
	}

	tunnel->buffer_len = 10240;
	tunnel->buffer = g_malloc (tunnel->buffer_len);

	/* Start the tunnel data transmittion */
	while (tunnel->running)
	{
		if (tunnel->tunnel_type == REMMINA_SSH_TUNNEL_XPORT ||
				tunnel->tunnel_type == REMMINA_SSH_TUNNEL_X11 ||
				tunnel->tunnel_type == REMMINA_SSH_TUNNEL_REVERSE)
		{
			if (first)
			{
				first = FALSE;
				/* Wait for a period of time for the first incoming connection */
				if (tunnel->tunnel_type == REMMINA_SSH_TUNNEL_X11)
				{
					channel = channel_accept_x11 (tunnel->x11_channel, 15000);
				}
				else
				{
					channel = channel_forward_accept (REMMINA_SSH (tunnel)->session, 15000);
				}
				if (!channel)
				{
					remmina_ssh_set_application_error (REMMINA_SSH (tunnel), _("No response from the server."));
					if (tunnel->disconnect_func)
					{
						(*tunnel->disconnect_func) (tunnel, tunnel->callback_data);
					}
					tunnel->thread = 0;
					return NULL;
				}
				if (tunnel->connect_func)
				{
					(*tunnel->connect_func) (tunnel, tunnel->callback_data);
				}
				if (tunnel->tunnel_type == REMMINA_SSH_TUNNEL_REVERSE)
				{
					/* For reverse tunnel, we only need one connection. */
					channel_forward_cancel (REMMINA_SSH (tunnel)->session, NULL, tunnel->port);
				}
			}
			else if (tunnel->tunnel_type != REMMINA_SSH_TUNNEL_REVERSE)
			{
				/* Poll once per some period of time if no incoming connections.
				 * Don't try to poll continuously as it will significantly slow down the loop */
				g_get_current_time (&t1);
				diff = (t1.tv_sec - t2.tv_sec) * 10 + (t1.tv_usec - t2.tv_usec) / 100000;
				if (diff > 1)
				{
					if (tunnel->tunnel_type == REMMINA_SSH_TUNNEL_X11)
					{
						channel = channel_accept_x11 (tunnel->x11_channel, 0);
					}
					else
					{
						channel = channel_forward_accept (REMMINA_SSH (tunnel)->session, 0);
					}
					if (channel == NULL)
					{
						t2 = t1;
					}
				}
			}

			if (channel)
			{
				if (tunnel->tunnel_type == REMMINA_SSH_TUNNEL_REVERSE)
				{
					sin.sin_family = AF_INET;
					sin.sin_port = htons (tunnel->localport);
					sin.sin_addr.s_addr = inet_addr ("127.0.0.1");
					sock = socket (AF_INET, SOCK_STREAM, 0);
					if (connect (sock, (struct sockaddr *) &sin, sizeof (sin)) < 0)
					{
						remmina_ssh_set_application_error (REMMINA_SSH (tunnel),
								"Cannot connect to local port %i.", tunnel->localport);
						close (sock);
						sock = -1;
					}
				}
				else
				{
					sock = remmina_public_open_xdisplay (tunnel->localdisplay);
				}
				if (sock >= 0)
				{
					remmina_ssh_tunnel_add_channel (tunnel, channel, sock);
				}
				else
				{
					/* Failed to create unix socket. Will this happen? */
					channel_close (channel);
					channel_free (channel);
				}
				channel = NULL;
			}
		}

		if (tunnel->num_channels <= 0)
		{
			/* No more connections. We should quit */
			break;
		}

		timeout.tv_sec = 0;
		timeout.tv_usec = 200000;

		FD_ZERO (&set);
		maxfd = 0;
		for (i = 0; i < tunnel->num_channels; i++)
		{
			if (tunnel->sockets[i] > maxfd)
			{
				maxfd = tunnel->sockets[i];
			}
			FD_SET (tunnel->sockets[i], &set);
		}

		ret = ssh_select (tunnel->channels, tunnel->channels_out, maxfd + 1, &set, &timeout);
		if (!tunnel->running) break;
		if (ret == SSH_EINTR) continue;
		if (ret == -1) break;

		i = 0;
		while (tunnel->running && i < tunnel->num_channels)
		{
			disconnected = FALSE;
			if (FD_ISSET (tunnel->sockets[i], &set))
			{
				while (!disconnected &&
						(len = read (tunnel->sockets[i], tunnel->buffer, tunnel->buffer_len)) > 0)
				{
					for (ptr = tunnel->buffer, lenw = 0; len > 0; len -= lenw, ptr += lenw)
					{
						lenw = channel_write (tunnel->channels[i], (char*) ptr, len);
						if (lenw <= 0)
						{
							disconnected = TRUE;
							break;
						}
					}
				}
				if (len == 0) disconnected = TRUE;
			}
			if (disconnected)
			{
				remmina_ssh_tunnel_remove_channel (tunnel, i);
				continue;
			}
			i++;
		}
		if (!tunnel->running) break;

		i = 0;
		while (tunnel->running && i < tunnel->num_channels)
		{
			disconnected = FALSE;

			if (!tunnel->socketbuffers[i])
			{
				len = channel_poll (tunnel->channels[i], 0);
				if (len == SSH_ERROR || len == SSH_EOF)
				{
					disconnected = TRUE;
				}
				else if (len > 0)
				{
					tunnel->socketbuffers[i] = remmina_ssh_tunnel_buffer_new (len);
					len = channel_read_nonblocking (tunnel->channels[i], tunnel->socketbuffers[i]->data, len, 0);
					if (len <= 0)
					{
						disconnected = TRUE;
					}
					else
					{
						tunnel->socketbuffers[i]->len = len;
					}
				}
			}

			if (!disconnected && tunnel->socketbuffers[i])
			{
				for (lenw = 0; tunnel->socketbuffers[i]->len > 0;
						tunnel->socketbuffers[i]->len -= lenw, tunnel->socketbuffers[i]->ptr += lenw)
				{
					lenw = write (tunnel->sockets[i], tunnel->socketbuffers[i]->ptr, tunnel->socketbuffers[i]->len);
					if (lenw == -1 && errno == EAGAIN && tunnel->running)
					{
						/* Sometimes we cannot write to a socket (always EAGAIN), probably because it's internal
						 * buffer is full. We need read the pending bytes from the socket first. so here we simply
						 * break, leave the buffer there, and continue with other data */
						break;
					}
					if (lenw <= 0)
					{
						disconnected = TRUE;
						break;
					}
				}
				if (tunnel->socketbuffers[i]->len <= 0)
				{
					remmina_ssh_tunnel_buffer_free (tunnel->socketbuffers[i]);
					tunnel->socketbuffers[i] = NULL;
				}
			}

			if (disconnected)
			{
				remmina_ssh_tunnel_remove_channel (tunnel, i);
				continue;
			}
			i++;
		}
	}

	remmina_ssh_tunnel_close_all_channels (tunnel);

	return NULL;
}