Exemplo n.º 1
0
/* I/O callback for fd-based connections. It calls the read/write handlers
 * provided by the connection's sock_ops, which must be valid. It returns 0.
 */
int conn_fd_handler(int fd)
{
	struct connection *conn = fdtab[fd].owner;

	if (unlikely(!conn))
		return 0;

	/* before engaging there, we clear the new WAIT_* flags so that we can
	 * more easily detect an EAGAIN condition from anywhere.
	 */
	conn->flags &= ~(CO_FL_WAIT_DATA|CO_FL_WAIT_ROOM|CO_FL_WAIT_RD|CO_FL_WAIT_WR);

 process_handshake:
	/* The handshake callbacks are called in sequence. If either of them is
	 * missing something, it must enable the required polling at the socket
	 * layer of the connection. Polling state is not guaranteed when entering
	 * these handlers, so any handshake handler which does not complete its
	 * work must explicitly disable events it's not interested in.
	 */
	while (unlikely(conn->flags & CO_FL_HANDSHAKE)) {
		if (unlikely(conn->flags & (CO_FL_ERROR|CO_FL_WAIT_RD|CO_FL_WAIT_WR)))
			goto leave;

		if (conn->flags & CO_FL_ACCEPT_PROXY)
			if (!conn_recv_proxy(conn, CO_FL_ACCEPT_PROXY))
				goto leave;

		if (conn->flags & CO_FL_SI_SEND_PROXY)
			if (!conn_si_send_proxy(conn, CO_FL_SI_SEND_PROXY))
				goto leave;
#ifdef USE_OPENSSL
		if (conn->flags & CO_FL_SSL_WAIT_HS)
			if (!ssl_sock_handshake(conn, CO_FL_SSL_WAIT_HS))
				goto leave;
#endif
	}

	/* Once we're purely in the data phase, we disable handshake polling */
	if (!(conn->flags & CO_FL_POLL_SOCK))
		__conn_sock_stop_both(conn);

	/* Maybe we need to finish initializing an incoming session. The
	 * function may fail and cause the connection to be destroyed, thus
	 * we must not use it anymore and should immediately leave instead.
	 */
	if ((conn->flags & CO_FL_INIT_SESS) &&
	    conn_session_complete(conn, CO_FL_INIT_SESS) < 0)
		return 0;

	/* The data transfer starts here and stops on error and handshakes */
	if ((fdtab[fd].ev & (FD_POLL_IN | FD_POLL_HUP | FD_POLL_ERR)) &&
	    !(conn->flags & (CO_FL_WAIT_RD|CO_FL_WAIT_ROOM|CO_FL_ERROR|CO_FL_HANDSHAKE)))
		conn->app_cb->recv(conn);

	if ((fdtab[fd].ev & (FD_POLL_OUT | FD_POLL_ERR)) &&
	    !(conn->flags & (CO_FL_WAIT_WR|CO_FL_WAIT_DATA|CO_FL_ERROR|CO_FL_HANDSHAKE)))
		conn->app_cb->send(conn);

	if (unlikely(conn->flags & CO_FL_ERROR))
		goto leave;

	/* It may happen during the data phase that a handshake is
	 * enabled again (eg: SSL)
	 */
	if (unlikely(conn->flags & CO_FL_HANDSHAKE))
		goto process_handshake;

	if (unlikely(conn->flags & CO_FL_WAIT_L4_CONN) && !(conn->flags & CO_FL_WAIT_WR)) {
		/* still waiting for a connection to establish and nothing was
		 * attempted yet to probe the connection. Then let's retry the
		 * connect().
		 */
		if (!tcp_connect_probe(conn))
			goto leave;
	}

 leave:
	/* we may need to release the connection which is an embryonic session */
	if ((conn->flags & (CO_FL_ERROR|CO_FL_INIT_SESS)) == (CO_FL_ERROR|CO_FL_INIT_SESS)) {
		conn->flags |= CO_FL_ERROR;
		conn_session_complete(conn, CO_FL_INIT_SESS);
		return 0;
	}

	if (conn->flags & CO_FL_NOTIFY_SI)
		conn_notify_si(conn);

	/* Last check, verify if the connection just established */
	if (unlikely(!(conn->flags & (CO_FL_WAIT_L4_CONN | CO_FL_WAIT_L6_CONN | CO_FL_CONNECTED))))
		conn->flags |= CO_FL_CONNECTED;

	/* remove the events before leaving */
	fdtab[fd].ev &= ~(FD_POLL_IN | FD_POLL_OUT | FD_POLL_HUP | FD_POLL_ERR);

	/* commit polling changes */
	conn_cond_update_polling(conn);
	return 0;
}
Exemplo n.º 2
0
/* I/O callback for fd-based connections. It calls the read/write handlers
 * provided by the connection's sock_ops, which must be valid. It returns 0.
 */
int conn_fd_handler(int fd)
{
	struct connection *conn = fdtab[fd].owner;
	unsigned int flags;

	if (unlikely(!conn))
		return 0;

	conn_refresh_polling_flags(conn);
	flags = conn->flags & ~CO_FL_ERROR; /* ensure to call the wake handler upon error */

 process_handshake:
	/* The handshake callbacks are called in sequence. If either of them is
	 * missing something, it must enable the required polling at the socket
	 * layer of the connection. Polling state is not guaranteed when entering
	 * these handlers, so any handshake handler which does not complete its
	 * work must explicitly disable events it's not interested in. Error
	 * handling is also performed here in order to reduce the number of tests
	 * around.
	 */
	while (unlikely(conn->flags & (CO_FL_HANDSHAKE | CO_FL_ERROR))) {
		if (unlikely(conn->flags & CO_FL_ERROR))
			goto leave;

		if (conn->flags & CO_FL_ACCEPT_PROXY)
			if (!conn_recv_proxy(conn, CO_FL_ACCEPT_PROXY))
				goto leave;

		if (conn->flags & CO_FL_SEND_PROXY)
			if (!conn_si_send_proxy(conn, CO_FL_SEND_PROXY))
				goto leave;
#ifdef USE_OPENSSL
		if (conn->flags & CO_FL_SSL_WAIT_HS)
			if (!ssl_sock_handshake(conn, CO_FL_SSL_WAIT_HS))
				goto leave;
#endif
	}

	/* Once we're purely in the data phase, we disable handshake polling */
	if (!(conn->flags & CO_FL_POLL_SOCK))
		__conn_sock_stop_both(conn);

	/* The data layer might not be ready yet (eg: when using embryonic
	 * sessions). If we're about to move data, we must initialize it first.
	 * The function may fail and cause the connection to be destroyed, thus
	 * we must not use it anymore and should immediately leave instead.
	 */
	if ((conn->flags & CO_FL_INIT_DATA) && conn->data->init(conn) < 0)
		return 0;

	/* The data transfer starts here and stops on error and handshakes. Note
	 * that we must absolutely test conn->xprt at each step in case it suddenly
	 * changes due to a quick unexpected close().
	 */
	if (conn->xprt && fd_recv_ready(fd) &&
	    ((conn->flags & (CO_FL_DATA_RD_ENA|CO_FL_WAIT_ROOM|CO_FL_ERROR|CO_FL_HANDSHAKE)) == CO_FL_DATA_RD_ENA)) {
		/* force detection of a flag change : it's impossible to have both
		 * CONNECTED and WAIT_CONN so we're certain to trigger a change.
		 */
		flags = CO_FL_WAIT_L4_CONN | CO_FL_CONNECTED;
		conn->data->recv(conn);
	}

	if (conn->xprt && fd_send_ready(fd) &&
	    ((conn->flags & (CO_FL_DATA_WR_ENA|CO_FL_WAIT_DATA|CO_FL_ERROR|CO_FL_HANDSHAKE)) == CO_FL_DATA_WR_ENA)) {
		/* force detection of a flag change : it's impossible to have both
		 * CONNECTED and WAIT_CONN so we're certain to trigger a change.
		 */
		flags = CO_FL_WAIT_L4_CONN | CO_FL_CONNECTED;
		conn->data->send(conn);
	}

	/* It may happen during the data phase that a handshake is
	 * enabled again (eg: SSL)
	 */
	if (unlikely(conn->flags & (CO_FL_HANDSHAKE | CO_FL_ERROR)))
		goto process_handshake;

	if (unlikely(conn->flags & CO_FL_WAIT_L4_CONN)) {
		/* still waiting for a connection to establish and nothing was
		 * attempted yet to probe the connection. Then let's retry the
		 * connect().
		 */
		if (!tcp_connect_probe(conn))
			goto leave;
	}

 leave:
	/* The wake callback may be used to process a critical error and abort the
	 * connection. If so, we don't want to go further as the connection will
	 * have been released and the FD destroyed.
	 */
	if ((conn->flags & CO_FL_WAKE_DATA) &&
	    ((conn->flags ^ flags) & CO_FL_CONN_STATE) &&
	    conn->data->wake(conn) < 0)
		return 0;

	/* Last check, verify if the connection just established */
	if (unlikely(!(conn->flags & (CO_FL_WAIT_L4_CONN | CO_FL_WAIT_L6_CONN | CO_FL_CONNECTED))))
		conn->flags |= CO_FL_CONNECTED;

	/* remove the events before leaving */
	fdtab[fd].ev &= FD_POLL_STICKY;

	/* commit polling changes */
	conn_cond_update_polling(conn);
	return 0;
}