/* 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;
}
/* This function is used for inter-stream-interface calls. It is called by the
* producer to inform the consumer side that it may be interested in checking
* for data in the buffer. Note that it intentionally does not update timeouts,
* so that we can still check them later at wake-up.
*/
static void stream_int_chk_snd_conn(struct stream_interface *si)
{
struct channel *ob = si->ob;
struct connection *conn = __objt_conn(si->end);
if (unlikely(si->state > SI_ST_EST || (ob->flags & CF_SHUTW)))
return;
if (unlikely(channel_is_empty(ob))) /* called with nothing to send ! */
return;
if (!ob->pipe && /* spliced data wants to be forwarded ASAP */
!(si->flags & SI_FL_WAIT_DATA)) /* not waiting for data */
return;
if (conn->flags & (CO_FL_DATA_WR_ENA|CO_FL_CURR_WR_ENA)) {
/* already subscribed to write notifications, will be called
* anyway, so let's avoid calling it especially if the reader
* is not ready.
*/
return;
}
/* Before calling the data-level operations, we have to prepare
* the polling flags to ensure we properly detect changes.
*/
conn_refresh_polling_flags(conn);
__conn_data_want_send(conn);
if (!(conn->flags & (CO_FL_HANDSHAKE|CO_FL_WAIT_L4_CONN|CO_FL_WAIT_L6_CONN))) {
si_conn_send(conn);
if (conn->flags & CO_FL_ERROR) {
/* Write error on the file descriptor */
__conn_data_stop_both(conn);
si->flags |= SI_FL_ERR;
goto out_wakeup;
}
}
/* OK, so now we know that some data might have been sent, and that we may
* have to poll first. We have to do that too if the buffer is not empty.
*/
if (channel_is_empty(ob)) {
/* the connection is established but we can't write. Either the
* buffer is empty, or we just refrain from sending because the
* ->o limit was reached. Maybe we just wrote the last
* chunk and need to close.
*/
__conn_data_stop_send(conn);
if (((ob->flags & (CF_SHUTW|CF_AUTO_CLOSE|CF_SHUTW_NOW)) ==
(CF_AUTO_CLOSE|CF_SHUTW_NOW)) &&
(si->state == SI_ST_EST)) {
si_shutw(si);
goto out_wakeup;
}
if ((ob->flags & (CF_SHUTW|CF_SHUTW_NOW)) == 0)
si->flags |= SI_FL_WAIT_DATA;
ob->wex = TICK_ETERNITY;
}
else {
/* Otherwise there are remaining data to be sent in the buffer,
* which means we have to poll before doing so.
*/
__conn_data_want_send(conn);
si->flags &= ~SI_FL_WAIT_DATA;
if (!tick_isset(ob->wex))
ob->wex = tick_add_ifset(now_ms, ob->wto);
}
if (likely(ob->flags & CF_WRITE_ACTIVITY)) {
/* update timeout if we have written something */
if ((ob->flags & (CF_SHUTW|CF_WRITE_PARTIAL)) == CF_WRITE_PARTIAL &&
!channel_is_empty(ob))
ob->wex = tick_add_ifset(now_ms, ob->wto);
if (tick_isset(si->ib->rex) && !(si->flags & SI_FL_INDEP_STR)) {
/* Note: to prevent the client from expiring read timeouts
* during writes, we refresh it. We only do this if the
* interface is not configured for "independent streams",
* because for some applications it's better not to do this,
* for instance when continuously exchanging small amounts
* of data which can full the socket buffers long before a
* write timeout is detected.
*/
si->ib->rex = tick_add_ifset(now_ms, si->ib->rto);
}
}
/* in case of special condition (error, shutdown, end of write...), we
* have to notify the task.
*/
if (likely((ob->flags & (CF_WRITE_NULL|CF_WRITE_ERROR|CF_SHUTW)) ||
((ob->flags & CF_WAKE_WRITE) &&
((channel_is_empty(si->ob) && !ob->to_forward) ||
si->state != SI_ST_EST)))) {
out_wakeup:
if (!(si->flags & SI_FL_DONT_WAKE) && si->owner)
task_wakeup(si->owner, TASK_WOKEN_IO);
}
/* commit possible polling changes */
conn_cond_update_polling(conn);
}
/* 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;
}
/*
* This function performs a shutdown-write on a stream interface attached to
* a connection in a connected or init state (it does nothing for other
* states). It either shuts the write side or marks itself as closed. The
* buffer flags are updated to reflect the new state. It does also close
* everything if the SI was marked as being in error state. If there is a
* data-layer shutdown, it is called.
*/
static void stream_int_shutw_conn(struct stream_interface *si)
{
struct connection *conn = __objt_conn(si->end);
struct channel *ic = si_ic(si);
struct channel *oc = si_oc(si);
oc->flags &= ~CF_SHUTW_NOW;
if (oc->flags & CF_SHUTW)
return;
oc->flags |= CF_SHUTW;
oc->wex = TICK_ETERNITY;
si->flags &= ~SI_FL_WAIT_DATA;
switch (si->state) {
case SI_ST_EST:
/* we have to shut before closing, otherwise some short messages
* may never leave the system, especially when there are remaining
* unread data in the socket input buffer, or when nolinger is set.
* However, if SI_FL_NOLINGER is explicitly set, we know there is
* no risk so we close both sides immediately.
*/
if (si->flags & SI_FL_ERR) {
/* quick close, the socket is alredy shut anyway */
}
else if (si->flags & SI_FL_NOLINGER) {
/* unclean data-layer shutdown */
conn_data_shutw_hard(conn);
}
else {
/* clean data-layer shutdown */
conn_data_shutw(conn);
/* If the stream interface is configured to disable half-open
* connections, we'll skip the shutdown(), but only if the
* read size is already closed. Otherwise we can't support
* closed write with pending read (eg: abortonclose while
* waiting for the server).
*/
if (!(si->flags & SI_FL_NOHALF) || !(ic->flags & (CF_SHUTR|CF_DONT_READ))) {
/* We shutdown transport layer */
conn_sock_shutw(conn);
if (!(ic->flags & (CF_SHUTR|CF_DONT_READ))) {
/* OK just a shutw, but we want the caller
* to disable polling on this FD if exists.
*/
conn_cond_update_polling(conn);
return;
}
}
}
/* fall through */
case SI_ST_CON:
/* we may have to close a pending connection, and mark the
* response buffer as shutr
*/
conn_full_close(conn);
/* fall through */
case SI_ST_CER:
case SI_ST_QUE:
case SI_ST_TAR:
si->state = SI_ST_DIS;
/* fall through */
default:
si->flags &= ~(SI_FL_WAIT_ROOM | SI_FL_NOLINGER);
ic->flags &= ~CF_SHUTR_NOW;
ic->flags |= CF_SHUTR;
ic->rex = TICK_ETERNITY;
si->exp = TICK_ETERNITY;
}
}
