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Diffstat (limited to '')
| -rw-r--r-- | src/stconn.c | 2050 |
1 files changed, 2050 insertions, 0 deletions
diff --git a/src/stconn.c b/src/stconn.c new file mode 100644 index 0000000..8e3ae7e --- /dev/null +++ b/src/stconn.c @@ -0,0 +1,2050 @@ +/* + * stream connector management functions + * + * Copyright 2021 Christopher Faulet <cfaulet@haproxy.com> + * + * This program is free software; you can redistribute it and/or + * modify it under the terms of the GNU General Public License + * as published by the Free Software Foundation; either version + * 2 of the License, or (at your option) any later version. + * + */ + +#include <haproxy/api.h> +#include <haproxy/applet.h> +#include <haproxy/connection.h> +#include <haproxy/check.h> +#include <haproxy/http_ana.h> +#include <haproxy/pipe.h> +#include <haproxy/pool.h> +#include <haproxy/sample.h> +#include <haproxy/sc_strm.h> +#include <haproxy/stconn.h> +#include <haproxy/xref.h> + +DECLARE_POOL(pool_head_connstream, "stconn", sizeof(struct stconn)); +DECLARE_POOL(pool_head_sedesc, "sedesc", sizeof(struct sedesc)); + +/* functions used by default on a detached stream connector */ +static void sc_app_abort(struct stconn *sc); +static void sc_app_shut(struct stconn *sc); +static void sc_app_chk_rcv(struct stconn *sc); +static void sc_app_chk_snd(struct stconn *sc); + +/* functions used on a mux-based stream connector */ +static void sc_app_abort_conn(struct stconn *sc); +static void sc_app_shut_conn(struct stconn *sc); +static void sc_app_chk_rcv_conn(struct stconn *sc); +static void sc_app_chk_snd_conn(struct stconn *sc); + +/* functions used on an applet-based stream connector */ +static void sc_app_abort_applet(struct stconn *sc); +static void sc_app_shut_applet(struct stconn *sc); +static void sc_app_chk_rcv_applet(struct stconn *sc); +static void sc_app_chk_snd_applet(struct stconn *sc); + +static int sc_conn_process(struct stconn *sc); +static int sc_conn_recv(struct stconn *sc); +static int sc_conn_send(struct stconn *sc); +static int sc_applet_process(struct stconn *sc); + +/* stream connector operations for connections */ +struct sc_app_ops sc_app_conn_ops = { + .chk_rcv = sc_app_chk_rcv_conn, + .chk_snd = sc_app_chk_snd_conn, + .abort = sc_app_abort_conn, + .shutdown= sc_app_shut_conn, + .wake = sc_conn_process, + .name = "STRM", +}; + +/* stream connector operations for embedded tasks */ +struct sc_app_ops sc_app_embedded_ops = { + .chk_rcv = sc_app_chk_rcv, + .chk_snd = sc_app_chk_snd, + .abort = sc_app_abort, + .shutdown= sc_app_shut, + .wake = NULL, /* may never be used */ + .name = "NONE", /* may never be used */ +}; + +/* stream connector operations for applets */ +struct sc_app_ops sc_app_applet_ops = { + .chk_rcv = sc_app_chk_rcv_applet, + .chk_snd = sc_app_chk_snd_applet, + .abort = sc_app_abort_applet, + .shutdown= sc_app_shut_applet, + .wake = sc_applet_process, + .name = "STRM", +}; + +/* stream connector for health checks on connections */ +struct sc_app_ops sc_app_check_ops = { + .chk_rcv = NULL, + .chk_snd = NULL, + .abort = NULL, + .shutdown= NULL, + .wake = wake_srv_chk, + .name = "CHCK", +}; + +/* Initializes an endpoint */ +void sedesc_init(struct sedesc *sedesc) +{ + sedesc->se = NULL; + sedesc->conn = NULL; + sedesc->sc = NULL; + sedesc->lra = TICK_ETERNITY; + sedesc->fsb = TICK_ETERNITY; + sedesc->xref.peer = NULL; + se_fl_setall(sedesc, SE_FL_NONE); + + sedesc->iobuf.pipe = NULL; + sedesc->iobuf.buf = NULL; + sedesc->iobuf.offset = sedesc->iobuf.data = 0; + sedesc->iobuf.flags = IOBUF_FL_NONE; +} + +/* Tries to alloc an endpoint and initialize it. Returns NULL on failure. */ +struct sedesc *sedesc_new() +{ + struct sedesc *sedesc; + + sedesc = pool_alloc(pool_head_sedesc); + if (unlikely(!sedesc)) + return NULL; + + sedesc_init(sedesc); + return sedesc; +} + +/* Releases an endpoint. It is the caller responsibility to be sure it is safe + * and it is not shared with another entity + */ +void sedesc_free(struct sedesc *sedesc) +{ + if (sedesc) { + if (sedesc->iobuf.pipe) + put_pipe(sedesc->iobuf.pipe); + pool_free(pool_head_sedesc, sedesc); + } +} + +/* Tries to allocate a new stconn and initialize its main fields. On + * failure, nothing is allocated and NULL is returned. It is an internal + * function. The caller must, at least, set the SE_FL_ORPHAN or SE_FL_DETACHED + * flag. + */ +static struct stconn *sc_new(struct sedesc *sedesc) +{ + struct stconn *sc; + + sc = pool_alloc(pool_head_connstream); + + if (unlikely(!sc)) + goto alloc_error; + + sc->obj_type = OBJ_TYPE_SC; + sc->flags = SC_FL_NONE; + sc->state = SC_ST_INI; + sc->ioto = TICK_ETERNITY; + sc->room_needed = 0; + sc->app = NULL; + sc->app_ops = NULL; + sc->src = NULL; + sc->dst = NULL; + sc->wait_event.tasklet = NULL; + sc->wait_event.events = 0; + + /* If there is no endpoint, allocate a new one now */ + if (!sedesc) { + sedesc = sedesc_new(); + if (unlikely(!sedesc)) + goto alloc_error; + } + sc->sedesc = sedesc; + sedesc->sc = sc; + + return sc; + + alloc_error: + pool_free(pool_head_connstream, sc); + return NULL; +} + +/* Creates a new stream connector and its associated stream from a mux. <sd> must + * be defined. It returns NULL on error. On success, the new stream connector is + * returned. In this case, SE_FL_ORPHAN flag is removed. + */ +struct stconn *sc_new_from_endp(struct sedesc *sd, struct session *sess, struct buffer *input) +{ + struct stconn *sc; + + sc = sc_new(sd); + if (unlikely(!sc)) + return NULL; + if (unlikely(!stream_new(sess, sc, input))) { + sd->sc = NULL; + if (sc->sedesc != sd) { + /* none was provided so sc_new() allocated one */ + sedesc_free(sc->sedesc); + } + pool_free(pool_head_connstream, sc); + se_fl_set(sd, SE_FL_ORPHAN); + return NULL; + } + se_fl_clr(sd, SE_FL_ORPHAN); + return sc; +} + +/* Creates a new stream connector from an stream. There is no endpoint here, thus it + * will be created by sc_new(). So the SE_FL_DETACHED flag is set. It returns + * NULL on error. On success, the new stream connector is returned. + */ +struct stconn *sc_new_from_strm(struct stream *strm, unsigned int flags) +{ + struct stconn *sc; + + sc = sc_new(NULL); + if (unlikely(!sc)) + return NULL; + sc->flags |= flags; + sc_ep_set(sc, SE_FL_DETACHED); + sc->app = &strm->obj_type; + sc->app_ops = &sc_app_embedded_ops; + return sc; +} + +/* Creates a new stream connector from an health-check. There is no endpoint here, + * thus it will be created by sc_new(). So the SE_FL_DETACHED flag is set. It + * returns NULL on error. On success, the new stream connector is returned. + */ +struct stconn *sc_new_from_check(struct check *check, unsigned int flags) +{ + struct stconn *sc; + + sc = sc_new(NULL); + if (unlikely(!sc)) + return NULL; + sc->flags |= flags; + sc_ep_set(sc, SE_FL_DETACHED); + sc->app = &check->obj_type; + sc->app_ops = &sc_app_check_ops; + return sc; +} + +/* Releases a stconn previously allocated by sc_new(), as well as its + * endpoint, if it exists. This function is called internally or on error path. + */ +void sc_free(struct stconn *sc) +{ + sockaddr_free(&sc->src); + sockaddr_free(&sc->dst); + if (sc->sedesc) { + BUG_ON(!sc_ep_test(sc, SE_FL_DETACHED)); + sedesc_free(sc->sedesc); + } + tasklet_free(sc->wait_event.tasklet); + pool_free(pool_head_connstream, sc); +} + +/* Conditionally removes a stream connector if it is detached and if there is no app + * layer defined. Except on error path, this one must be used. if release, the + * pointer on the SC is set to NULL. + */ +static void sc_free_cond(struct stconn **scp) +{ + struct stconn *sc = *scp; + + if (!sc->app && (!sc->sedesc || sc_ep_test(sc, SE_FL_DETACHED))) { + sc_free(sc); + *scp = NULL; + } +} + + +/* Attaches a stconn to a mux endpoint and sets the endpoint ctx. Returns + * -1 on error and 0 on success. SE_FL_DETACHED flag is removed. This function is + * called from a mux when it is attached to a stream or a health-check. + */ +int sc_attach_mux(struct stconn *sc, void *sd, void *ctx) +{ + struct connection *conn = ctx; + struct sedesc *sedesc = sc->sedesc; + + if (sc_strm(sc)) { + if (!sc->wait_event.tasklet) { + sc->wait_event.tasklet = tasklet_new(); + if (!sc->wait_event.tasklet) + return -1; + sc->wait_event.tasklet->process = sc_conn_io_cb; + sc->wait_event.tasklet->context = sc; + sc->wait_event.events = 0; + } + + sc->app_ops = &sc_app_conn_ops; + xref_create(&sc->sedesc->xref, &sc_opposite(sc)->sedesc->xref); + } + else if (sc_check(sc)) { + if (!sc->wait_event.tasklet) { + sc->wait_event.tasklet = tasklet_new(); + if (!sc->wait_event.tasklet) + return -1; + sc->wait_event.tasklet->process = srv_chk_io_cb; + sc->wait_event.tasklet->context = sc; + sc->wait_event.events = 0; + } + + sc->app_ops = &sc_app_check_ops; + } + + sedesc->se = sd; + sedesc->conn = ctx; + se_fl_set(sedesc, SE_FL_T_MUX); + se_fl_clr(sedesc, SE_FL_DETACHED); + if (!conn->ctx) + conn->ctx = sc; + return 0; +} + +/* Attaches a stconn to an applet endpoint and sets the endpoint + * ctx. Returns -1 on error and 0 on success. SE_FL_DETACHED flag is + * removed. This function is called by a stream when a backend applet is + * registered. + */ +static void sc_attach_applet(struct stconn *sc, void *sd) +{ + sc->sedesc->se = sd; + sc_ep_set(sc, SE_FL_T_APPLET); + sc_ep_clr(sc, SE_FL_DETACHED); + if (sc_strm(sc)) { + sc->app_ops = &sc_app_applet_ops; + xref_create(&sc->sedesc->xref, &sc_opposite(sc)->sedesc->xref); + } +} + +/* Attaches a stconn to a app layer and sets the relevant + * callbacks. Returns -1 on error and 0 on success. SE_FL_ORPHAN flag is + * removed. This function is called by a stream when it is created to attach it + * on the stream connector on the client side. + */ +int sc_attach_strm(struct stconn *sc, struct stream *strm) +{ + sc->app = &strm->obj_type; + sc_ep_clr(sc, SE_FL_ORPHAN); + sc_ep_report_read_activity(sc); + if (sc_ep_test(sc, SE_FL_T_MUX)) { + sc->wait_event.tasklet = tasklet_new(); + if (!sc->wait_event.tasklet) + return -1; + sc->wait_event.tasklet->process = sc_conn_io_cb; + sc->wait_event.tasklet->context = sc; + sc->wait_event.events = 0; + + sc->app_ops = &sc_app_conn_ops; + } + else if (sc_ep_test(sc, SE_FL_T_APPLET)) { + sc->app_ops = &sc_app_applet_ops; + } + else { + sc->app_ops = &sc_app_embedded_ops; + } + return 0; +} + +/* Detaches the stconn from the endpoint, if any. For a connecrion, if a + * mux owns the connection ->detach() callback is called. Otherwise, it means + * the stream connector owns the connection. In this case the connection is closed + * and released. For an applet, the appctx is released. If still allocated, the + * endpoint is reset and flag as detached. If the app layer is also detached, + * the stream connector is released. + */ +static void sc_detach_endp(struct stconn **scp) +{ + struct stconn *sc = *scp; + struct xref *peer; + + if (!sc) + return; + + + /* Remove my link in the original objects. */ + peer = xref_get_peer_and_lock(&sc->sedesc->xref); + if (peer) + xref_disconnect(&sc->sedesc->xref, peer); + + if (sc_ep_test(sc, SE_FL_T_MUX)) { + struct connection *conn = __sc_conn(sc); + struct sedesc *sedesc = sc->sedesc; + + if (conn->mux) { + if (sc->wait_event.events != 0) + conn->mux->unsubscribe(sc, sc->wait_event.events, &sc->wait_event); + se_fl_set(sedesc, SE_FL_ORPHAN); + sedesc->sc = NULL; + sc->sedesc = NULL; + conn->mux->detach(sedesc); + } + else { + /* It's too early to have a mux, let's just destroy + * the connection + */ + conn_stop_tracking(conn); + conn_full_close(conn); + if (conn->destroy_cb) + conn->destroy_cb(conn); + conn_free(conn); + } + } + else if (sc_ep_test(sc, SE_FL_T_APPLET)) { + struct appctx *appctx = __sc_appctx(sc); + + sc_ep_set(sc, SE_FL_ORPHAN); + sc->sedesc->sc = NULL; + sc->sedesc = NULL; + appctx_shut(appctx); + appctx_free(appctx); + } + + if (sc->sedesc) { + /* the SD wasn't used and can be recycled */ + sc->sedesc->se = NULL; + sc->sedesc->conn = NULL; + sc->sedesc->flags = 0; + sc_ep_set(sc, SE_FL_DETACHED); + } + + /* FIXME: Rest SC for now but must be reviewed. SC flags are only + * connection related for now but this will evolved + */ + sc->flags &= SC_FL_ISBACK; + if (sc_strm(sc)) + sc->app_ops = &sc_app_embedded_ops; + else + sc->app_ops = NULL; + sc_free_cond(scp); +} + +/* Detaches the stconn from the app layer. If there is no endpoint attached + * to the stconn + */ +static void sc_detach_app(struct stconn **scp) +{ + struct stconn *sc = *scp; + + if (!sc) + return; + + sc->app = NULL; + sc->app_ops = NULL; + sockaddr_free(&sc->src); + sockaddr_free(&sc->dst); + + tasklet_free(sc->wait_event.tasklet); + sc->wait_event.tasklet = NULL; + sc->wait_event.events = 0; + sc_free_cond(scp); +} + +/* Destroy the stconn. It is detached from its endpoint and its + * application. After this call, the stconn must be considered as released. + */ +void sc_destroy(struct stconn *sc) +{ + sc_detach_endp(&sc); + sc_detach_app(&sc); + BUG_ON_HOT(sc); +} + +/* Resets the stream connector endpoint. It happens when the app layer want to renew + * its endpoint. For a connection retry for instance. If a mux or an applet is + * attached, a new endpoint is created. Returns -1 on error and 0 on success. + */ +int sc_reset_endp(struct stconn *sc) +{ + struct sedesc *new_sd; + + BUG_ON(!sc->app); + + if (!__sc_endp(sc)) { + /* endpoint not attached or attached to a mux with no + * target. Thus the endpoint will not be release but just + * reset. The app is still attached, the sc will not be + * released. + */ + sc_detach_endp(&sc); + return 0; + } + + /* allocate the new endpoint first to be able to set error if it + * fails */ + new_sd = sedesc_new(); + if (!unlikely(new_sd)) + return -1; + + /* The app is still attached, the sc will not be released */ + sc_detach_endp(&sc); + BUG_ON(!sc); + BUG_ON(sc->sedesc); + sc->sedesc = new_sd; + sc->sedesc->sc = sc; + sc_ep_set(sc, SE_FL_DETACHED); + return 0; +} + + +/* Create an applet to handle a stream connector as a new appctx. The SC will + * wake it up every time it is solicited. The appctx must be deleted by the task + * handler using sc_detach_endp(), possibly from within the function itself. + * It also pre-initializes the applet's context and returns it (or NULL in case + * it could not be allocated). + */ +struct appctx *sc_applet_create(struct stconn *sc, struct applet *app) +{ + struct appctx *appctx; + + appctx = appctx_new_here(app, sc->sedesc); + if (!appctx) + return NULL; + sc_attach_applet(sc, appctx); + appctx->t->nice = __sc_strm(sc)->task->nice; + applet_need_more_data(appctx); + appctx_wakeup(appctx); + + sc->state = SC_ST_RDY; + return appctx; +} + +/* Conditionally forward the close to the write side. It return 1 if it can be + * forwarded. It is the caller responsibility to forward the close to the write + * side. Otherwise, 0 is returned. In this case, SC_FL_SHUT_WANTED flag may be set on + * the consumer SC if we are only waiting for the outgoing data to be flushed. + */ +static inline int sc_cond_forward_shut(struct stconn *sc) +{ + /* The close must not be forwarded */ + if (!(sc->flags & (SC_FL_EOS|SC_FL_ABRT_DONE)) || !(sc->flags & SC_FL_NOHALF)) + return 0; + + if (co_data(sc_ic(sc)) && !(sc_ic(sc)->flags & CF_WRITE_TIMEOUT)) { + /* the shutdown cannot be forwarded now because + * we should flush outgoing data first. But instruct the output + * channel it should be done ASAP. + */ + sc_schedule_shutdown(sc); + return 0; + } + + /* the close can be immediately forwarded to the write side */ + return 1; +} + + +static inline int sc_is_fastfwd_supported(struct stconn *sc) +{ + return (!(global.tune.no_zero_copy_fwd & NO_ZERO_COPY_FWD) && + sc_ep_test(sc, SE_FL_MAY_FASTFWD_PROD) && + sc_ep_test(sc_opposite(sc), SE_FL_MAY_FASTFWD_CONS) && + sc_ic(sc)->to_forward); +} +/* + * This function performs a shutdown-read on a detached stream connector in a + * connected or init state (it does nothing for other states). It either shuts + * the read side or marks itself as closed. The buffer flags are updated to + * reflect the new state. If the stream connector has SC_FL_NOHALF, we also + * forward the close to the write side. The owner task is woken up if it exists. + */ +static void sc_app_abort(struct stconn *sc) +{ + struct channel *ic = sc_ic(sc); + + if (sc->flags & (SC_FL_EOS|SC_FL_ABRT_DONE)) + return; + + sc->flags |= SC_FL_ABRT_DONE; + ic->flags |= CF_READ_EVENT; + + if (!sc_state_in(sc->state, SC_SB_CON|SC_SB_RDY|SC_SB_EST)) + return; + + if (sc->flags & SC_FL_SHUT_DONE) { + sc->state = SC_ST_DIS; + if (sc->flags & SC_FL_ISBACK) + __sc_strm(sc)->conn_exp = TICK_ETERNITY; + } + else if (sc_cond_forward_shut(sc)) + return sc_app_shut(sc); + + /* note that if the task exists, it must unregister itself once it runs */ + if (!(sc->flags & SC_FL_DONT_WAKE)) + task_wakeup(sc_strm_task(sc), TASK_WOKEN_IO); +} + +/* + * This function performs a shutdown-write on a detached stream connector 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 SC was marked as + * being in error state. The owner task is woken up if it exists. + */ +static void sc_app_shut(struct stconn *sc) +{ + struct channel *ic = sc_ic(sc); + struct channel *oc = sc_oc(sc); + + sc->flags &= ~SC_FL_SHUT_WANTED; + if (sc->flags & SC_FL_SHUT_DONE) + return; + sc->flags |= SC_FL_SHUT_DONE; + oc->flags |= CF_WRITE_EVENT; + sc_set_hcto(sc); + + switch (sc->state) { + case SC_ST_RDY: + case SC_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 SC_FL_NOLINGER is explicitly set, we know there is + * no risk so we close both sides immediately. + */ + if (!(sc->flags & (SC_FL_ERROR|SC_FL_NOLINGER|SC_FL_EOS|SC_FL_ABRT_DONE)) && + !(ic->flags & CF_DONT_READ)) + return; + + __fallthrough; + case SC_ST_CON: + case SC_ST_CER: + case SC_ST_QUE: + case SC_ST_TAR: + /* Note that none of these states may happen with applets */ + sc->state = SC_ST_DIS; + __fallthrough; + default: + sc->flags &= ~SC_FL_NOLINGER; + sc->flags |= SC_FL_ABRT_DONE; + if (sc->flags & SC_FL_ISBACK) + __sc_strm(sc)->conn_exp = TICK_ETERNITY; + } + + /* note that if the task exists, it must unregister itself once it runs */ + if (!(sc->flags & SC_FL_DONT_WAKE)) + task_wakeup(sc_strm_task(sc), TASK_WOKEN_IO); +} + +/* default chk_rcv function for scheduled tasks */ +static void sc_app_chk_rcv(struct stconn *sc) +{ + if (sc_ep_have_ff_data(sc_opposite(sc))) { + /* stop reading */ + sc_need_room(sc, -1); + } + else { + /* (re)start reading */ + if (!(sc->flags & SC_FL_DONT_WAKE)) + task_wakeup(sc_strm_task(sc), TASK_WOKEN_IO); + } +} + +/* default chk_snd function for scheduled tasks */ +static void sc_app_chk_snd(struct stconn *sc) +{ + struct channel *oc = sc_oc(sc); + + if (unlikely(sc->state != SC_ST_EST || (sc->flags & SC_FL_SHUT_DONE))) + return; + + if (!sc_ep_test(sc, SE_FL_WAIT_DATA) || /* not waiting for data */ + (!co_data(oc) && !sc_ep_have_ff_data(sc))) /* called with nothing to send ! */ + return; + + /* Otherwise there are remaining data to be sent in the buffer, + * so we tell the handler. + */ + sc_ep_clr(sc, SE_FL_WAIT_DATA); + if (!(sc->flags & SC_FL_DONT_WAKE)) + task_wakeup(sc_strm_task(sc), TASK_WOKEN_IO); +} + +/* + * This function performs a shutdown-read on a stream connector attached to + * a connection in a connected or init state (it does nothing for other + * states). It either shuts the read side or marks itself as closed. The buffer + * flags are updated to reflect the new state. If the stream connector has + * SC_FL_NOHALF, we also forward the close to the write side. If a control + * layer is defined, then it is supposed to be a socket layer and file + * descriptors are then shutdown or closed accordingly. The function + * automatically disables polling if needed. + */ +static void sc_app_abort_conn(struct stconn *sc) +{ + struct channel *ic = sc_ic(sc); + + BUG_ON(!sc_conn(sc)); + + if (sc->flags & (SC_FL_EOS|SC_FL_ABRT_DONE)) + return; + sc->flags |= SC_FL_ABRT_DONE; + ic->flags |= CF_READ_EVENT; + + if (!sc_state_in(sc->state, SC_SB_CON|SC_SB_RDY|SC_SB_EST)) + return; + + if (sc->flags & SC_FL_SHUT_DONE) { + sc_conn_shut(sc); + sc->state = SC_ST_DIS; + if (sc->flags & SC_FL_ISBACK) + __sc_strm(sc)->conn_exp = TICK_ETERNITY; + } + else if (sc_cond_forward_shut(sc)) + return sc_app_shut_conn(sc); +} + +/* + * This function performs a shutdown-write on a stream connector 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 SC was marked as being in error state. If there is a + * data-layer shutdown, it is called. + */ +static void sc_app_shut_conn(struct stconn *sc) +{ + struct channel *ic = sc_ic(sc); + struct channel *oc = sc_oc(sc); + + BUG_ON(!sc_conn(sc)); + + sc->flags &= ~SC_FL_SHUT_WANTED; + if (sc->flags & SC_FL_SHUT_DONE) + return; + sc->flags |= SC_FL_SHUT_DONE; + oc->flags |= CF_WRITE_EVENT; + sc_set_hcto(sc); + + switch (sc->state) { + case SC_ST_RDY: + case SC_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 SC_FL_NOLINGER is explicitly set, we know there is + * no risk so we close both sides immediately. + */ + if (sc->flags & SC_FL_NOLINGER) { + /* unclean data-layer shutdown, typically an aborted request + * or a forwarded shutdown from a client to a server due to + * option abortonclose. No need for the TLS layer to try to + * emit a shutdown message. + */ + sc_conn_shutw(sc, CO_SHW_SILENT); + } + else { + /* clean data-layer shutdown. This only happens on the + * frontend side, or on the backend side when forwarding + * a client close in TCP mode or in HTTP TUNNEL mode + * while option abortonclose is set. We want the TLS + * layer to try to signal it to the peer before we close. + */ + sc_conn_shutw(sc, CO_SHW_NORMAL); + + if (!(sc->flags & (SC_FL_EOS|SC_FL_ABRT_DONE)) && !(ic->flags & CF_DONT_READ)) + return; + } + + __fallthrough; + case SC_ST_CON: + /* we may have to close a pending connection, and mark the + * response buffer as abort + */ + sc_conn_shut(sc); + __fallthrough; + case SC_ST_CER: + case SC_ST_QUE: + case SC_ST_TAR: + sc->state = SC_ST_DIS; + __fallthrough; + default: + sc->flags &= ~SC_FL_NOLINGER; + sc->flags |= SC_FL_ABRT_DONE; + if (sc->flags & SC_FL_ISBACK) + __sc_strm(sc)->conn_exp = TICK_ETERNITY; + } +} + +/* This function is used for inter-stream connector calls. It is called by the + * consumer to inform the producer side that it may be interested in checking + * for free space in the buffer. Note that it intentionally does not update + * timeouts, so that we can still check them later at wake-up. This function is + * dedicated to connection-based stream connectors. + */ +static void sc_app_chk_rcv_conn(struct stconn *sc) +{ + BUG_ON(!sc_conn(sc)); + + /* (re)start reading */ + if (sc_state_in(sc->state, SC_SB_CON|SC_SB_RDY|SC_SB_EST)) + tasklet_wakeup(sc->wait_event.tasklet); +} + + +/* This function is used for inter-stream connector 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 sc_app_chk_snd_conn(struct stconn *sc) +{ + struct channel *oc = sc_oc(sc); + + BUG_ON(!sc_conn(sc)); + + if (unlikely(!sc_state_in(sc->state, SC_SB_RDY|SC_SB_EST) || + (sc->flags & SC_FL_SHUT_DONE))) + return; + + if (unlikely(!co_data(oc) && !sc_ep_have_ff_data(sc))) /* called with nothing to send ! */ + return; + + if (!sc_ep_have_ff_data(sc) && /* data wants to be fast-forwarded ASAP */ + !sc_ep_test(sc, SE_FL_WAIT_DATA)) /* not waiting for data */ + return; + + if (!(sc->wait_event.events & SUB_RETRY_SEND)) + sc_conn_send(sc); + + if (sc_ep_test(sc, SE_FL_ERROR | SE_FL_ERR_PENDING) || sc_is_conn_error(sc)) { + /* Write error on the file descriptor */ + BUG_ON(sc_ep_test(sc, SE_FL_EOS|SE_FL_ERROR|SE_FL_ERR_PENDING) == (SE_FL_EOS|SE_FL_ERR_PENDING)); + 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 (!co_data(oc)) { + /* 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. + */ + if ((oc->flags & CF_AUTO_CLOSE) && + ((sc->flags & (SC_FL_SHUT_DONE|SC_FL_SHUT_WANTED)) == SC_FL_SHUT_WANTED) && + sc_state_in(sc->state, SC_SB_RDY|SC_SB_EST)) { + sc_shutdown(sc); + goto out_wakeup; + } + + if ((sc->flags & (SC_FL_SHUT_DONE|SC_FL_SHUT_WANTED)) == 0) + sc_ep_set(sc, SE_FL_WAIT_DATA); + } + else { + /* Otherwise there are remaining data to be sent in the buffer, + * which means we have to poll before doing so. + */ + sc_ep_clr(sc, SE_FL_WAIT_DATA); + } + + /* in case of special condition (error, shutdown, end of write...), we + * have to notify the task. + */ + if (likely((sc->flags & SC_FL_SHUT_DONE) || + ((oc->flags & CF_WRITE_EVENT) && sc->state < SC_ST_EST) || + ((oc->flags & CF_WAKE_WRITE) && + ((!co_data(oc) && !oc->to_forward) || + !sc_state_in(sc->state, SC_SB_EST))))) { + out_wakeup: + if (!(sc->flags & SC_FL_DONT_WAKE)) + task_wakeup(sc_strm_task(sc), TASK_WOKEN_IO); + } +} + +/* + * This function performs a shutdown-read on a stream connector attached to an + * applet in a connected or init state (it does nothing for other states). It + * either shuts the read side or marks itself as closed. The buffer flags are + * updated to reflect the new state. If the stream connector has SC_FL_NOHALF, + * we also forward the close to the write side. The owner task is woken up if + * it exists. + */ +static void sc_app_abort_applet(struct stconn *sc) +{ + struct channel *ic = sc_ic(sc); + + BUG_ON(!sc_appctx(sc)); + + if (sc->flags & (SC_FL_EOS|SC_FL_ABRT_DONE)) + return; + sc->flags |= SC_FL_ABRT_DONE; + ic->flags |= CF_READ_EVENT; + + /* Note: on abort, we don't call the applet */ + + if (!sc_state_in(sc->state, SC_SB_CON|SC_SB_RDY|SC_SB_EST)) + return; + + if (sc->flags & SC_FL_SHUT_DONE) { + appctx_shut(__sc_appctx(sc)); + sc->state = SC_ST_DIS; + if (sc->flags & SC_FL_ISBACK) + __sc_strm(sc)->conn_exp = TICK_ETERNITY; + } + else if (sc_cond_forward_shut(sc)) + return sc_app_shut_applet(sc); +} + +/* + * This function performs a shutdown-write on a stream connector attached to an + * applet 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. The owner task is woken up if it exists. + */ +static void sc_app_shut_applet(struct stconn *sc) +{ + struct channel *ic = sc_ic(sc); + struct channel *oc = sc_oc(sc); + + BUG_ON(!sc_appctx(sc)); + + sc->flags &= ~SC_FL_SHUT_WANTED; + if (sc->flags & SC_FL_SHUT_DONE) + return; + sc->flags |= SC_FL_SHUT_DONE; + oc->flags |= CF_WRITE_EVENT; + sc_set_hcto(sc); + + /* on shutw we always wake the applet up */ + appctx_wakeup(__sc_appctx(sc)); + + switch (sc->state) { + case SC_ST_RDY: + case SC_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 SC_FL_NOLINGER is explicitly set, we know there is + * no risk so we close both sides immediately. + */ + if (!(sc->flags & (SC_FL_ERROR|SC_FL_NOLINGER|SC_FL_EOS|SC_FL_ABRT_DONE)) && + !(ic->flags & CF_DONT_READ)) + return; + + __fallthrough; + case SC_ST_CON: + case SC_ST_CER: + case SC_ST_QUE: + case SC_ST_TAR: + /* Note that none of these states may happen with applets */ + appctx_shut(__sc_appctx(sc)); + sc->state = SC_ST_DIS; + __fallthrough; + default: + sc->flags &= ~SC_FL_NOLINGER; + sc->flags |= SC_FL_ABRT_DONE; + if (sc->flags & SC_FL_ISBACK) + __sc_strm(sc)->conn_exp = TICK_ETERNITY; + } +} + +/* chk_rcv function for applets */ +static void sc_app_chk_rcv_applet(struct stconn *sc) +{ + BUG_ON(!sc_appctx(sc)); + + if (!sc_ep_have_ff_data(sc_opposite(sc))) { + /* (re)start reading */ + appctx_wakeup(__sc_appctx(sc)); + } +} + +/* chk_snd function for applets */ +static void sc_app_chk_snd_applet(struct stconn *sc) +{ + struct channel *oc = sc_oc(sc); + + BUG_ON(!sc_appctx(sc)); + + if (unlikely(sc->state != SC_ST_EST || (sc->flags & SC_FL_SHUT_DONE))) + return; + + /* we only wake the applet up if it was waiting for some data and is ready to consume it */ + if (!sc_ep_test(sc, SE_FL_WAIT_DATA|SE_FL_WONT_CONSUME)) + return; + + if (co_data(oc) || sc_ep_have_ff_data(sc)) { + /* (re)start sending */ + appctx_wakeup(__sc_appctx(sc)); + } +} + + +/* This function is designed to be called from within the stream handler to + * update the input channel's expiration timer and the stream connector's + * Rx flags based on the channel's flags. It needs to be called only once + * after the channel's flags have settled down, and before they are cleared, + * though it doesn't harm to call it as often as desired (it just slightly + * hurts performance). It must not be called from outside of the stream + * handler, as what it does will be used to compute the stream task's + * expiration. + */ +void sc_update_rx(struct stconn *sc) +{ + struct channel *ic = sc_ic(sc); + + if (sc->flags & (SC_FL_EOS|SC_FL_ABRT_DONE)) + return; + + /* Unblock the SC if it needs room and the free space is large enough (0 + * means it can always be unblocked). Do not unblock it if -1 was + * specified. + */ + if (!sc->room_needed || (sc->room_needed > 0 && channel_recv_max(ic) >= sc->room_needed)) + sc_have_room(sc); + + /* Read not closed, update FD status and timeout for reads */ + if (ic->flags & CF_DONT_READ) + sc_wont_read(sc); + else + sc_will_read(sc); + + sc_chk_rcv(sc); +} + +/* This function is designed to be called from within the stream handler to + * update the output channel's expiration timer and the stream connector's + * Tx flags based on the channel's flags. It needs to be called only once + * after the channel's flags have settled down, and before they are cleared, + * though it doesn't harm to call it as often as desired (it just slightly + * hurts performance). It must not be called from outside of the stream + * handler, as what it does will be used to compute the stream task's + * expiration. + */ +void sc_update_tx(struct stconn *sc) +{ + struct channel *oc = sc_oc(sc); + + if (sc->flags & SC_FL_SHUT_DONE) + return; + + /* Write not closed, update FD status and timeout for writes */ + if (!co_data(oc)) { + /* stop writing */ + if (!sc_ep_test(sc, SE_FL_WAIT_DATA)) { + if ((sc->flags & SC_FL_SHUT_WANTED) == 0) + sc_ep_set(sc, SE_FL_WAIT_DATA); + } + return; + } + + /* (re)start writing */ + sc_ep_clr(sc, SE_FL_WAIT_DATA); +} + +/* This function is the equivalent to sc_update() except that it's + * designed to be called from outside the stream handlers, typically the lower + * layers (applets, connections) after I/O completion. After updating the stream + * interface and timeouts, it will try to forward what can be forwarded, then to + * wake the associated task up if an important event requires special handling. + * It may update SE_FL_WAIT_DATA and/or SC_FL_NEED_ROOM, that the callers are + * encouraged to watch to take appropriate action. + * It should not be called from within the stream itself, sc_update() + * is designed for this. Please do not statify this function, it's often + * present in backtraces, it's useful to recognize it. + */ +void sc_notify(struct stconn *sc) +{ + struct channel *ic = sc_ic(sc); + struct channel *oc = sc_oc(sc); + struct stconn *sco = sc_opposite(sc); + struct task *task = sc_strm_task(sc); + + /* process consumer side */ + if (!co_data(oc)) { + struct connection *conn = sc_conn(sc); + + if (((sc->flags & (SC_FL_SHUT_DONE|SC_FL_SHUT_WANTED)) == SC_FL_SHUT_WANTED) && + (sc->state == SC_ST_EST) && (!conn || !(conn->flags & (CO_FL_WAIT_XPRT | CO_FL_EARLY_SSL_HS)))) + sc_shutdown(sc); + } + + /* indicate that we may be waiting for data from the output channel or + * we're about to close and can't expect more data if SC_FL_SHUT_WANTED is there. + */ + if (!(sc->flags & (SC_FL_SHUT_DONE|SC_FL_SHUT_WANTED))) + sc_ep_set(sc, SE_FL_WAIT_DATA); + else if ((sc->flags & (SC_FL_SHUT_DONE|SC_FL_SHUT_WANTED)) == SC_FL_SHUT_WANTED) + sc_ep_clr(sc, SE_FL_WAIT_DATA); + + if (oc->flags & CF_DONT_READ) + sc_wont_read(sco); + else + sc_will_read(sco); + + /* Notify the other side when we've injected data into the IC that + * needs to be forwarded. We can do fast-forwarding as soon as there + * are output data, but we avoid doing this if some of the data are + * not yet scheduled for being forwarded, because it is very likely + * that it will be done again immediately afterwards once the following + * data are parsed (eg: HTTP chunking). We only clear SC_FL_NEED_ROOM + * once we've emptied *some* of the output buffer, and not just when + * there is available room, because applets are often forced to stop + * before the buffer is full. We must not stop based on input data + * alone because an HTTP parser might need more data to complete the + * parsing. + */ + if (sc_ep_have_ff_data(sc_opposite(sc)) || + (co_data(ic) && sc_ep_test(sco, SE_FL_WAIT_DATA) && + (!(sc->flags & SC_FL_SND_EXP_MORE) || channel_full(ic, co_data(ic)) || channel_input_data(ic) == 0))) { + int new_len, last_len; + + last_len = co_data(ic) + sc_ep_ff_data(sco); + sc_chk_snd(sco); + new_len = co_data(ic) + sc_ep_ff_data(sco); + + /* check if the consumer has freed some space either in the + * buffer or in the pipe. + */ + if (!sc->room_needed || (new_len < last_len && (sc->room_needed < 0 || channel_recv_max(ic) >= sc->room_needed))) + sc_have_room(sc); + } + + if (!(ic->flags & CF_DONT_READ)) + sc_will_read(sc); + + sc_chk_rcv(sc); + sc_chk_rcv(sco); + + /* wake the task up only when needed */ + if (/* changes on the production side that must be handled: + * - An error on receipt: SC_FL_ERROR + * - A read event: shutdown for reads (CF_READ_EVENT + EOS/ABRT_DONE) + * end of input (CF_READ_EVENT + SC_FL_EOI) + * data received and no fast-forwarding (CF_READ_EVENT + !to_forward) + * read event while consumer side is not established (CF_READ_EVENT + sco->state != SC_ST_EST) + */ + ((ic->flags & CF_READ_EVENT) && ((sc->flags & SC_FL_EOI) || (sc->flags & (SC_FL_EOS|SC_FL_ABRT_DONE)) || !ic->to_forward || sco->state != SC_ST_EST)) || + (sc->flags & SC_FL_ERROR) || + + /* changes on the consumption side */ + sc_ep_test(sc, SE_FL_ERR_PENDING) || + ((oc->flags & CF_WRITE_EVENT) && + ((sc->state < SC_ST_EST) || + (sc->flags & SC_FL_SHUT_DONE) || + (((oc->flags & CF_WAKE_WRITE) || + (!(oc->flags & CF_AUTO_CLOSE) && + !(sc->flags & (SC_FL_SHUT_WANTED|SC_FL_SHUT_DONE)))) && + (sco->state != SC_ST_EST || + (!co_data(oc) && !oc->to_forward)))))) { + task_wakeup(task, TASK_WOKEN_IO); + } + else { + /* Update expiration date for the task and requeue it if not already expired */ + if (!tick_is_expired(task->expire, now_ms)) { + task->expire = tick_first(task->expire, sc_ep_rcv_ex(sc)); + task->expire = tick_first(task->expire, sc_ep_snd_ex(sc)); + task->expire = tick_first(task->expire, sc_ep_rcv_ex(sco)); + task->expire = tick_first(task->expire, sc_ep_snd_ex(sco)); + task->expire = tick_first(task->expire, ic->analyse_exp); + task->expire = tick_first(task->expire, oc->analyse_exp); + task->expire = tick_first(task->expire, __sc_strm(sc)->conn_exp); + + /* WARNING: Don't forget to remove this BUG_ON before 2.9.0 */ + BUG_ON(tick_is_expired(task->expire, now_ms)); + task_queue(task); + } + } + + if (ic->flags & CF_READ_EVENT) + sc->flags &= ~SC_FL_RCV_ONCE; +} + +/* + * This function propagates an end-of-stream received on a socket-based connection. + * It updates the stream connector. If the stream connector has SC_FL_NOHALF, + * the close is also forwarded to the write side as an abort. + */ +static void sc_conn_eos(struct stconn *sc) +{ + struct channel *ic = sc_ic(sc); + + BUG_ON(!sc_conn(sc)); + + if (sc->flags & (SC_FL_EOS|SC_FL_ABRT_DONE)) + return; + sc->flags |= SC_FL_EOS; + ic->flags |= CF_READ_EVENT; + sc_ep_report_read_activity(sc); + + if (!sc_state_in(sc->state, SC_SB_CON|SC_SB_RDY|SC_SB_EST)) + return; + + if (sc->flags & SC_FL_SHUT_DONE) + goto do_close; + + if (sc_cond_forward_shut(sc)) { + /* we want to immediately forward this close to the write side */ + /* force flag on ssl to keep stream in cache */ + sc_conn_shutw(sc, CO_SHW_SILENT); + goto do_close; + } + + /* otherwise that's just a normal read shutdown */ + return; + + do_close: + /* OK we completely close the socket here just as if we went through sc_shut[rw]() */ + sc_conn_shut(sc); + + sc->flags &= ~SC_FL_SHUT_WANTED; + sc->flags |= SC_FL_SHUT_DONE; + + sc->state = SC_ST_DIS; + if (sc->flags & SC_FL_ISBACK) + __sc_strm(sc)->conn_exp = TICK_ETERNITY; + return; +} + +/* + * This is the callback which is called by the connection layer to receive data + * into the buffer from the connection. It iterates over the mux layer's + * rcv_buf function. Please do not statify this function, it's often present in + * backtraces, it's useful to recognize it. + */ +int sc_conn_recv(struct stconn *sc) +{ + struct connection *conn = __sc_conn(sc); + struct channel *ic = sc_ic(sc); + int ret, max, cur_read = 0; + int read_poll = MAX_READ_POLL_LOOPS; + int flags = 0; + + /* If not established yet, do nothing. */ + if (sc->state != SC_ST_EST) + return 0; + + /* If another call to sc_conn_recv() failed, and we subscribed to + * recv events already, give up now. + */ + if ((sc->wait_event.events & SUB_RETRY_RECV) || sc_waiting_room(sc)) + return 0; + + /* maybe we were called immediately after an asynchronous abort */ + if (sc->flags & (SC_FL_EOS|SC_FL_ABRT_DONE)) + return 1; + + /* we must wait because the mux is not installed yet */ + if (!conn->mux) + return 0; + + /* stop immediately on errors. Note that we DON'T want to stop on + * POLL_ERR, as the poller might report a write error while there + * are still data available in the recv buffer. This typically + * happens when we send too large a request to a backend server + * which rejects it before reading it all. + */ + if (!sc_ep_test(sc, SE_FL_RCV_MORE)) { + if (!conn_xprt_ready(conn)) + return 0; + if (sc_ep_test(sc, SE_FL_ERROR)) + goto end_recv; + } + + /* prepare to detect if the mux needs more room */ + sc_ep_clr(sc, SE_FL_WANT_ROOM); + + if ((ic->flags & (CF_STREAMER | CF_STREAMER_FAST)) && !co_data(ic) && + global.tune.idle_timer && + (unsigned short)(now_ms - ic->last_read) >= global.tune.idle_timer) { + /* The buffer was empty and nothing was transferred for more + * than one second. This was caused by a pause and not by + * congestion. Reset any streaming mode to reduce latency. + */ + ic->xfer_small = 0; + ic->xfer_large = 0; + ic->flags &= ~(CF_STREAMER | CF_STREAMER_FAST); + } + +#if defined(USE_LINUX_SPLICE) + /* Detect if the splicing is possible depending on the stream policy */ + if ((global.tune.options & GTUNE_USE_SPLICE) && + (ic->to_forward >= MIN_SPLICE_FORWARD) && + ((!(sc->flags & SC_FL_ISBACK) && ((strm_fe(__sc_strm(sc))->options2|__sc_strm(sc)->be->options2) & PR_O2_SPLIC_REQ)) || + ((sc->flags & SC_FL_ISBACK) && ((strm_fe(__sc_strm(sc))->options2|__sc_strm(sc)->be->options2) & PR_O2_SPLIC_RTR)) || + ((ic->flags & CF_STREAMER_FAST) && ((strm_sess(__sc_strm(sc))->fe->options2|__sc_strm(sc)->be->options2) & PR_O2_SPLIC_AUT)))) + flags |= CO_RFL_MAY_SPLICE; +#endif + + /* First, let's see if we may fast-forward data from a side to the other + * one without using the channel buffer. + */ + if (sc_is_fastfwd_supported(sc)) { + if (channel_data(ic)) { + /* We're embarrassed, there are already data pending in + * the buffer and we don't want to have them at two + * locations at a time. Let's indicate we need some + * place and ask the consumer to hurry. + */ + flags |= CO_RFL_BUF_FLUSH; + goto abort_fastfwd; + } + ret = conn->mux->fastfwd(sc, ic->to_forward, flags); + if (ret < 0) + goto abort_fastfwd; + else if (ret > 0) { + if (ic->to_forward != CHN_INFINITE_FORWARD) + ic->to_forward -= ret; + ic->total += ret; + cur_read += ret; + ic->flags |= CF_READ_EVENT; + } + + if (sc_ep_test(sc, SE_FL_EOS | SE_FL_ERROR)) + goto end_recv; + + if (sc_ep_test(sc, SE_FL_WANT_ROOM)) + sc_need_room(sc, -1); + + if (sc_ep_test(sc, SE_FL_MAY_FASTFWD_PROD) && ic->to_forward) + goto done_recv; + } + + abort_fastfwd: + /* now we'll need a input buffer for the stream */ + if (!sc_alloc_ibuf(sc, &(__sc_strm(sc)->buffer_wait))) + goto end_recv; + + /* For an HTX stream, if the buffer is stuck (no output data with some + * input data) and if the HTX message is fragmented or if its free space + * wraps, we force an HTX deframentation. It is a way to have a + * contiguous free space nad to let the mux to copy as much data as + * possible. + * + * NOTE: A possible optim may be to let the mux decides if defrag is + * required or not, depending on amount of data to be xferred. + */ + if (IS_HTX_STRM(__sc_strm(sc)) && !co_data(ic)) { + struct htx *htx = htxbuf(&ic->buf); + + if (htx_is_not_empty(htx) && ((htx->flags & HTX_FL_FRAGMENTED) || htx_space_wraps(htx))) + htx_defrag(htx, NULL, 0); + } + + /* Instruct the mux it must subscribed for read events */ + if (!(sc->flags & SC_FL_ISBACK) && /* for frontend conns only */ + (sc_opposite(sc)->state != SC_ST_INI) && /* before backend connection setup */ + (__sc_strm(sc)->be->options & PR_O_ABRT_CLOSE)) /* if abortonclose option is set for the current backend */ + flags |= CO_RFL_KEEP_RECV; + + /* Important note : if we're called with POLL_IN|POLL_HUP, it means the read polling + * was enabled, which implies that the recv buffer was not full. So we have a guarantee + * that if such an event is not handled above in splice, it will be handled here by + * recv(). + */ + while (sc_ep_test(sc, SE_FL_RCV_MORE) || + (!(conn->flags & CO_FL_HANDSHAKE) && + (!sc_ep_test(sc, SE_FL_ERROR | SE_FL_EOS)) && !(sc->flags & (SC_FL_EOS|SC_FL_ABRT_DONE)))) { + int cur_flags = flags; + + /* Compute transient CO_RFL_* flags */ + if (co_data(ic)) { + cur_flags |= (CO_RFL_BUF_WET | CO_RFL_BUF_NOT_STUCK); + } + + /* <max> may be null. This is the mux responsibility to set + * SE_FL_RCV_MORE on the SC if more space is needed. + */ + max = channel_recv_max(ic); + ret = conn->mux->rcv_buf(sc, &ic->buf, max, cur_flags); + + if (sc_ep_test(sc, SE_FL_WANT_ROOM)) { + /* SE_FL_WANT_ROOM must not be reported if the channel's + * buffer is empty. + */ + BUG_ON(c_empty(ic)); + + sc_need_room(sc, channel_recv_max(ic) + 1); + /* Add READ_PARTIAL because some data are pending but + * cannot be xferred to the channel + */ + ic->flags |= CF_READ_EVENT; + sc_ep_report_read_activity(sc); + } + + if (ret <= 0) { + /* if we refrained from reading because we asked for a + * flush to satisfy rcv_pipe(), we must not subscribe + * and instead report that there's not enough room + * here to proceed. + */ + if (flags & CO_RFL_BUF_FLUSH) + sc_need_room(sc, -1); + break; + } + + cur_read += ret; + + /* if we're allowed to directly forward data, we must update ->o */ + if (ic->to_forward && !(sc_opposite(sc)->flags & (SC_FL_SHUT_DONE|SC_FL_SHUT_WANTED))) { + unsigned long fwd = ret; + if (ic->to_forward != CHN_INFINITE_FORWARD) { + if (fwd > ic->to_forward) + fwd = ic->to_forward; + ic->to_forward -= fwd; + } + c_adv(ic, fwd); + } + + ic->flags |= CF_READ_EVENT; + ic->total += ret; + + /* End-of-input reached, we can leave. In this case, it is + * important to break the loop to not block the SC because of + * the channel's policies.This way, we are still able to receive + * shutdowns. + */ + if (sc_ep_test(sc, SE_FL_EOI)) + break; + + if ((sc->flags & SC_FL_RCV_ONCE) || --read_poll <= 0) { + /* we don't expect to read more data */ + sc_wont_read(sc); + break; + } + + /* if too many bytes were missing from last read, it means that + * it's pointless trying to read again because the system does + * not have them in buffers. + */ + if (ret < max) { + /* if a streamer has read few data, it may be because we + * have exhausted system buffers. It's not worth trying + * again. + */ + if (ic->flags & CF_STREAMER) { + /* we're stopped by the channel's policy */ + sc_wont_read(sc); + break; + } + + /* if we read a large block smaller than what we requested, + * it's almost certain we'll never get anything more. + */ + if (ret >= global.tune.recv_enough) { + /* we're stopped by the channel's policy */ + sc_wont_read(sc); + break; + } + } + + /* if we are waiting for more space, don't try to read more data + * right now. + */ + if (sc->flags & (SC_FL_WONT_READ|SC_FL_NEED_BUFF|SC_FL_NEED_ROOM)) + break; + } /* while !flags */ + + done_recv: + if (!cur_read) + se_have_no_more_data(sc->sedesc); + else { + if ((ic->flags & (CF_STREAMER | CF_STREAMER_FAST)) && + (cur_read <= ic->buf.size / 2)) { + ic->xfer_large = 0; + ic->xfer_small++; + if (ic->xfer_small >= 3) { + /* we have read less than half of the buffer in + * one pass, and this happened at least 3 times. + * This is definitely not a streamer. + */ + ic->flags &= ~(CF_STREAMER | CF_STREAMER_FAST); + } + else if (ic->xfer_small >= 2) { + /* if the buffer has been at least half full twice, + * we receive faster than we send, so at least it + * is not a "fast streamer". + */ + ic->flags &= ~CF_STREAMER_FAST; + } + } + else if (!(ic->flags & CF_STREAMER_FAST) && (cur_read >= channel_data_limit(ic))) { + /* we read a full buffer at once */ + ic->xfer_small = 0; + ic->xfer_large++; + if (ic->xfer_large >= 3) { + /* we call this buffer a fast streamer if it manages + * to be filled in one call 3 consecutive times. + */ + ic->flags |= (CF_STREAMER | CF_STREAMER_FAST); + } + } + else { + ic->xfer_small = 0; + ic->xfer_large = 0; + } + ic->last_read = now_ms; + sc_ep_report_read_activity(sc); + } + + end_recv: + ret = (cur_read != 0); + + /* Report EOI on the channel if it was reached from the mux point of + * view. */ + if (sc_ep_test(sc, SE_FL_EOI) && !(sc->flags & SC_FL_EOI)) { + sc_ep_report_read_activity(sc); + sc->flags |= SC_FL_EOI; + ic->flags |= CF_READ_EVENT; + ret = 1; + } + + if (sc_ep_test(sc, SE_FL_EOS)) { + /* we received a shutdown */ + if (ic->flags & CF_AUTO_CLOSE) + sc_schedule_shutdown(sc_opposite(sc)); + sc_conn_eos(sc); + ret = 1; + } + + if (sc_ep_test(sc, SE_FL_ERROR)) { + sc->flags |= SC_FL_ERROR; + ret = 1; + } + else if (!cur_read && + !(sc->flags & (SC_FL_WONT_READ|SC_FL_NEED_BUFF|SC_FL_NEED_ROOM)) && + !(sc->flags & (SC_FL_EOS|SC_FL_ABRT_DONE))) { + /* Subscribe to receive events if we're blocking on I/O */ + conn->mux->subscribe(sc, SUB_RETRY_RECV, &sc->wait_event); + se_have_no_more_data(sc->sedesc); + } + else { + se_have_more_data(sc->sedesc); + ret = 1; + } + + return ret; +} + +/* This tries to perform a synchronous receive on the stream connector to + * try to collect last arrived data. In practice it's only implemented on + * stconns. Returns 0 if nothing was done, non-zero if new data or a + * shutdown were collected. This may result on some delayed receive calls + * to be programmed and performed later, though it doesn't provide any + * such guarantee. + */ +int sc_conn_sync_recv(struct stconn *sc) +{ + if (!sc_state_in(sc->state, SC_SB_RDY|SC_SB_EST)) + return 0; + + if (!sc_mux_ops(sc)) + return 0; // only stconns are supported + + if (sc->wait_event.events & SUB_RETRY_RECV) + return 0; // already subscribed + + if (!sc_is_recv_allowed(sc)) + return 0; // already failed + + return sc_conn_recv(sc); +} + +/* + * This function is called to send buffer data to a stream socket. + * It calls the mux layer's snd_buf function. It relies on the + * caller to commit polling changes. The caller should check conn->flags + * for errors. Please do not statify this function, it's often present in + * backtraces, it's useful to recognize it. + */ +int sc_conn_send(struct stconn *sc) +{ + struct connection *conn = __sc_conn(sc); + struct stconn *sco = sc_opposite(sc); + struct stream *s = __sc_strm(sc); + struct channel *oc = sc_oc(sc); + int ret; + int did_send = 0; + + if (sc_ep_test(sc, SE_FL_ERROR | SE_FL_ERR_PENDING) || sc_is_conn_error(sc)) { + /* We're probably there because the tasklet was woken up, + * but process_stream() ran before, detected there were an + * error and put the SC back to SC_ST_TAR. There's still + * CO_FL_ERROR on the connection but we don't want to add + * SE_FL_ERROR back, so give up + */ + if (sc->state < SC_ST_CON) + return 0; + BUG_ON(sc_ep_test(sc, SE_FL_EOS|SE_FL_ERROR|SE_FL_ERR_PENDING) == (SE_FL_EOS|SE_FL_ERR_PENDING)); + return 1; + } + + /* We're already waiting to be able to send, give up */ + if (sc->wait_event.events & SUB_RETRY_SEND) + return 0; + + /* we might have been called just after an asynchronous shutw */ + if (sc->flags & SC_FL_SHUT_DONE) + return 1; + + /* we must wait because the mux is not installed yet */ + if (!conn->mux) + return 0; + + if (sc_ep_have_ff_data(sc)) { + unsigned int send_flag = 0; + + if ((!(sc->flags & (SC_FL_SND_ASAP|SC_FL_SND_NEVERWAIT)) && + ((oc->to_forward && oc->to_forward != CHN_INFINITE_FORWARD) || + (sc->flags & SC_FL_SND_EXP_MORE) || + (IS_HTX_STRM(s) && + (!(sco->flags & (SC_FL_EOI|SC_FL_EOS|SC_FL_ABRT_DONE)) && htx_expect_more(htxbuf(&oc->buf)))))) || + ((oc->flags & CF_ISRESP) && + (oc->flags & CF_AUTO_CLOSE) && + (sc->flags & SC_FL_SHUT_WANTED))) + send_flag |= CO_SFL_MSG_MORE; + + if (oc->flags & CF_STREAMER) + send_flag |= CO_SFL_STREAMER; + + ret = conn->mux->resume_fastfwd(sc, send_flag); + if (ret > 0) + did_send = 1; + + if (sc_ep_have_ff_data(sc)) + goto end; + } + + /* At this point, the pipe is empty, but we may still have data pending + * in the normal buffer. + */ + if (co_data(oc)) { + /* when we're here, we already know that there is no spliced + * data left, and that there are sendable buffered data. + */ + + /* check if we want to inform the kernel that we're interested in + * sending more data after this call. We want this if : + * - we're about to close after this last send and want to merge + * the ongoing FIN with the last segment. + * - we know we can't send everything at once and must get back + * here because of unaligned data + * - there is still a finite amount of data to forward + * The test is arranged so that the most common case does only 2 + * tests. + */ + unsigned int send_flag = 0; + + if ((!(sc->flags & (SC_FL_SND_ASAP|SC_FL_SND_NEVERWAIT)) && + ((oc->to_forward && oc->to_forward != CHN_INFINITE_FORWARD) || + (sc->flags & SC_FL_SND_EXP_MORE) || + (IS_HTX_STRM(s) && + (!(sco->flags & (SC_FL_EOI|SC_FL_EOS|SC_FL_ABRT_DONE)) && htx_expect_more(htxbuf(&oc->buf)))))) || + ((oc->flags & CF_ISRESP) && + (oc->flags & CF_AUTO_CLOSE) && + (sc->flags & SC_FL_SHUT_WANTED))) + send_flag |= CO_SFL_MSG_MORE; + + if (oc->flags & CF_STREAMER) + send_flag |= CO_SFL_STREAMER; + + if (s->txn && s->txn->flags & TX_L7_RETRY && !b_data(&s->txn->l7_buffer)) { + /* If we want to be able to do L7 retries, copy + * the data we're about to send, so that we are able + * to resend them if needed + */ + /* Try to allocate a buffer if we had none. + * If it fails, the next test will just + * disable the l7 retries by setting + * l7_conn_retries to 0. + */ + if (s->txn->req.msg_state != HTTP_MSG_DONE) + s->txn->flags &= ~TX_L7_RETRY; + else { + if (b_alloc(&s->txn->l7_buffer) == NULL) + s->txn->flags &= ~TX_L7_RETRY; + else { + memcpy(b_orig(&s->txn->l7_buffer), + b_orig(&oc->buf), + b_size(&oc->buf)); + s->txn->l7_buffer.head = co_data(oc); + b_add(&s->txn->l7_buffer, co_data(oc)); + } + + } + } + + ret = conn->mux->snd_buf(sc, &oc->buf, co_data(oc), send_flag); + if (ret > 0) { + did_send = 1; + c_rew(oc, ret); + c_realign_if_empty(oc); + + if (!co_data(oc)) { + /* Always clear both flags once everything has been sent, they're one-shot */ + sc->flags &= ~(SC_FL_SND_ASAP|SC_FL_SND_EXP_MORE); + } + /* if some data remain in the buffer, it's only because the + * system buffers are full, we will try next time. + */ + } + } + + end: + if (did_send) { + oc->flags |= CF_WRITE_EVENT | CF_WROTE_DATA; + if (sc->state == SC_ST_CON) + sc->state = SC_ST_RDY; + } + + if (!sco->room_needed || (did_send && (sco->room_needed < 0 || channel_recv_max(sc_oc(sc)) >= sco->room_needed))) + sc_have_room(sco); + + if (sc_ep_test(sc, SE_FL_ERROR | SE_FL_ERR_PENDING)) { + oc->flags |= CF_WRITE_EVENT; + BUG_ON(sc_ep_test(sc, SE_FL_EOS|SE_FL_ERROR|SE_FL_ERR_PENDING) == (SE_FL_EOS|SE_FL_ERR_PENDING)); + if (sc_ep_test(sc, SE_FL_ERROR)) + sc->flags |= SC_FL_ERROR; + return 1; + } + + /* FIXME: Must be reviewed for FF */ + if (!co_data(oc) && !sc_ep_have_ff_data(sc)) { + if (did_send) + sc_ep_report_send_activity(sc); + /* If fast-forwarding is blocked, unblock it now to check for + * receive on the other side + */ + if (sc->sedesc->iobuf.flags & IOBUF_FL_FF_BLOCKED) { + sc->sedesc->iobuf.flags &= ~IOBUF_FL_FF_BLOCKED; + sc_have_room(sco); + did_send = 1; + } + } + else { + /* We couldn't send all of our data, let the mux know we'd like to send more */ + conn->mux->subscribe(sc, SUB_RETRY_SEND, &sc->wait_event); + if (sc_state_in(sc->state, SC_SB_EST|SC_SB_DIS|SC_SB_CLO)) + sc_ep_report_blocked_send(sc, did_send); + } + + return did_send; +} + +/* perform a synchronous send() for the stream connector. The CF_WRITE_EVENT + * flag are cleared prior to the attempt, and will possibly be updated in case + * of success. + */ +void sc_conn_sync_send(struct stconn *sc) +{ + struct channel *oc = sc_oc(sc); + + oc->flags &= ~CF_WRITE_EVENT; + + if (sc->flags & SC_FL_SHUT_DONE) + return; + + if (!co_data(oc)) + return; + + if (!sc_state_in(sc->state, SC_SB_CON|SC_SB_RDY|SC_SB_EST)) + return; + + if (!sc_mux_ops(sc)) + return; + + sc_conn_send(sc); +} + +/* Called by I/O handlers after completion.. It propagates + * connection flags to the stream connector, updates the stream (which may or + * may not take this opportunity to try to forward data), then update the + * connection's polling based on the channels and stream connector's final + * states. The function always returns 0. Please do not statify this function, + * it's often present in backtraces, it's useful to recognize it. + */ +int sc_conn_process(struct stconn *sc) +{ + struct connection *conn = __sc_conn(sc); + struct channel *ic = sc_ic(sc); + struct channel *oc = sc_oc(sc); + + BUG_ON(!conn); + + /* If we have data to send, try it now */ + if ((co_data(oc) || sc_ep_have_ff_data(sc)) && + !(sc->wait_event.events & SUB_RETRY_SEND)) + sc_conn_send(sc); + + /* First step, report to the stream connector what was detected at the + * connection layer : errors and connection establishment. + * Only add SC_FL_ERROR if we're connected, or we're attempting to + * connect, we may get there because we got woken up, but only run + * after process_stream() noticed there were an error, and decided + * to retry to connect, the connection may still have CO_FL_ERROR, + * and we don't want to add SC_FL_ERROR back + * + * Note: This test is only required because sc_conn_process is also the SI + * wake callback. Otherwise sc_conn_recv()/sc_conn_send() already take + * care of it. + */ + + if (sc->state >= SC_ST_CON) { + if (sc_is_conn_error(sc)) + sc->flags |= SC_FL_ERROR; + } + + /* If we had early data, and the handshake ended, then + * we can remove the flag, and attempt to wake the task up, + * in the event there's an analyser waiting for the end of + * the handshake. + */ + if (!(conn->flags & (CO_FL_WAIT_XPRT | CO_FL_EARLY_SSL_HS)) && + sc_ep_test(sc, SE_FL_WAIT_FOR_HS)) { + sc_ep_clr(sc, SE_FL_WAIT_FOR_HS); + task_wakeup(sc_strm_task(sc), TASK_WOKEN_MSG); + } + + if (!sc_state_in(sc->state, SC_SB_EST|SC_SB_DIS|SC_SB_CLO) && + (conn->flags & CO_FL_WAIT_XPRT) == 0) { + if (sc->flags & SC_FL_ISBACK) + __sc_strm(sc)->conn_exp = TICK_ETERNITY; + oc->flags |= CF_WRITE_EVENT; + if (sc->state == SC_ST_CON) + sc->state = SC_ST_RDY; + } + + /* Report EOS on the channel if it was reached from the mux point of + * view. + * + * Note: This test is only required because sc_conn_process is also the SI + * wake callback. Otherwise sc_conn_recv()/sc_conn_send() already take + * care of it. + */ + if (sc_ep_test(sc, SE_FL_EOS) && !(sc->flags & SC_FL_EOS)) { + /* we received a shutdown */ + if (ic->flags & CF_AUTO_CLOSE) + sc_schedule_shutdown(sc_opposite(sc)); + sc_conn_eos(sc); + } + + /* Report EOI on the channel if it was reached from the mux point of + * view. + * + * Note: This test is only required because sc_conn_process is also the SI + * wake callback. Otherwise sc_conn_recv()/sc_conn_send() already take + * care of it. + */ + if (sc_ep_test(sc, SE_FL_EOI) && !(sc->flags & SC_FL_EOI)) { + sc->flags |= SC_FL_EOI; + ic->flags |= CF_READ_EVENT; + sc_ep_report_read_activity(sc); + } + + if (sc_ep_test(sc, SE_FL_ERROR)) + sc->flags |= SC_FL_ERROR; + + /* Second step : update the stream connector and channels, try to forward any + * pending data, then possibly wake the stream up based on the new + * stream connector status. + */ + sc_notify(sc); + stream_release_buffers(__sc_strm(sc)); + return 0; +} + +/* This is the ->process() function for any stream connector's wait_event task. + * It's assigned during the stream connector's initialization, for any type of + * stream connector. Thus it is always safe to perform a tasklet_wakeup() on a + * stream connector, as the presence of the SC is checked there. + */ +struct task *sc_conn_io_cb(struct task *t, void *ctx, unsigned int state) +{ + struct stconn *sc = ctx; + int ret = 0; + + if (!sc_conn(sc)) + return t; + + if (!(sc->wait_event.events & SUB_RETRY_SEND) && (co_data(sc_oc(sc)) || sc_ep_have_ff_data(sc) || (sc->sedesc->iobuf.flags & IOBUF_FL_FF_BLOCKED))) + ret = sc_conn_send(sc); + if (!(sc->wait_event.events & SUB_RETRY_RECV)) + ret |= sc_conn_recv(sc); + if (ret != 0) + sc_conn_process(sc); + + stream_release_buffers(__sc_strm(sc)); + return t; +} + +/* + * This function propagates an end-of-stream received from an applet. It + * updates the stream connector. If it is is already shut, the applet is + * released. Otherwise, we try to forward the shutdown, immediately or ASAP. + */ +static void sc_applet_eos(struct stconn *sc) +{ + struct channel *ic = sc_ic(sc); + + BUG_ON(!sc_appctx(sc)); + + if (sc->flags & (SC_FL_EOS|SC_FL_ABRT_DONE)) + return; + sc->flags |= SC_FL_EOS; + ic->flags |= CF_READ_EVENT; + sc_ep_report_read_activity(sc); + + /* Note: on abort, we don't call the applet */ + + if (!sc_state_in(sc->state, SC_SB_CON|SC_SB_RDY|SC_SB_EST)) + return; + + if (sc->flags & SC_FL_SHUT_DONE) { + appctx_shut(__sc_appctx(sc)); + sc->state = SC_ST_DIS; + if (sc->flags & SC_FL_ISBACK) + __sc_strm(sc)->conn_exp = TICK_ETERNITY; + } + else if (sc_cond_forward_shut(sc)) + return sc_app_shut_applet(sc); +} + +/* Callback to be used by applet handlers upon completion. It updates the stream + * (which may or may not take this opportunity to try to forward data), then + * may re-enable the applet's based on the channels and stream connector's final + * states. Please do not statify this function, it's often present in backtraces, + * it's useful to recognize it. + */ +int sc_applet_process(struct stconn *sc) +{ + struct channel *ic = sc_ic(sc); + + BUG_ON(!sc_appctx(sc)); + + /* Report EOI on the channel if it was reached from the applet point of + * view. */ + if (sc_ep_test(sc, SE_FL_EOI) && !(sc->flags & SC_FL_EOI)) { + sc_ep_report_read_activity(sc); + sc->flags |= SC_FL_EOI; + ic->flags |= CF_READ_EVENT; + } + + if (sc_ep_test(sc, SE_FL_ERROR)) + sc->flags |= SC_FL_ERROR; + + if (sc_ep_test(sc, SE_FL_EOS)) { + /* we received a shutdown */ + sc_applet_eos(sc); + } + + BUG_ON(sc_ep_test(sc, SE_FL_HAVE_NO_DATA|SE_FL_EOI) == SE_FL_EOI); + + /* If the applet wants to write and the channel is closed, it's a + * broken pipe and it must be reported. + */ + if (!sc_ep_test(sc, SE_FL_HAVE_NO_DATA) && (sc->flags & (SC_FL_EOS|SC_FL_ABRT_DONE))) + sc_ep_set(sc, SE_FL_ERROR); + + /* automatically mark the applet having data available if it reported + * begin blocked by the channel. + */ + if ((sc->flags & (SC_FL_WONT_READ|SC_FL_NEED_BUFF|SC_FL_NEED_ROOM)) || + sc_ep_test(sc, SE_FL_APPLET_NEED_CONN)) + applet_have_more_data(__sc_appctx(sc)); + + /* update the stream connector, channels, and possibly wake the stream up */ + sc_notify(sc); + stream_release_buffers(__sc_strm(sc)); + + /* sc_notify may have passed through chk_snd and released some blocking + * flags. Process_stream will consider those flags to wake up the + * appctx but in the case the task is not in runqueue we may have to + * wakeup the appctx immediately. + */ + if (sc_is_recv_allowed(sc) || sc_is_send_allowed(sc)) + appctx_wakeup(__sc_appctx(sc)); + return 0; +} + + +/* Prepares an endpoint upgrade. We don't now at this stage if the upgrade will + * succeed or not and if the stconn will be reused by the new endpoint. Thus, + * for now, only pretend the stconn is detached. + */ +void sc_conn_prepare_endp_upgrade(struct stconn *sc) +{ + BUG_ON(!sc_conn(sc) || !sc->app); + sc_ep_clr(sc, SE_FL_T_MUX); + sc_ep_set(sc, SE_FL_DETACHED); +} + +/* Endpoint upgrade failed. Restore the stconn state. */ +void sc_conn_abort_endp_upgrade(struct stconn *sc) +{ + sc_ep_set(sc, SE_FL_T_MUX); + sc_ep_clr(sc, SE_FL_DETACHED); +} + +/* Commit the endpoint upgrade. If stconn is attached, it means the new endpoint + * use it. So we do nothing. Otherwise, the stconn will be destroy with the + * overlying stream. So, it means we must commit the detach. +*/ +void sc_conn_commit_endp_upgrade(struct stconn *sc) +{ + if (!sc_ep_test(sc, SE_FL_DETACHED)) + return; + sc_detach_endp(&sc); + /* Because it was already set as detached, the sedesc must be preserved */ + BUG_ON(!sc); + BUG_ON(!sc->sedesc); +} + +/* return the frontend or backend mux stream ID. + */ +static int +smp_fetch_sid(const struct arg *args, struct sample *smp, const char *kw, void *private) +{ + struct connection *conn; + struct stconn *sc; + int64_t sid = 0; + + if (!smp->strm) + return 0; + + sc = (kw[0] == 'f' ? smp->strm->scf : smp->strm->scb); + conn = sc_conn(sc); + + /* No connection */ + if (!conn) + return 0; + + /* No mux install, this may change */ + if (!conn->mux) { + smp->flags |= SMP_F_MAY_CHANGE; + return 0; + } + + /* No sctl, report sid=0 in this case */ + if (conn->mux->sctl) { + if (conn->mux->sctl(sc, MUX_SCTL_SID, &sid) == -1) + return 0; + } + + smp->flags = SMP_F_VOL_TXN; + smp->data.type = SMP_T_SINT; + smp->data.u.sint = sid; + + return 1; +} + +/* Note: must not be declared <const> as its list will be overwritten. + * Note: fetches that may return multiple types should be declared using the + * appropriate pseudo-type. If not available it must be declared as the lowest + * common denominator, the type that can be casted into all other ones. + */ +static struct sample_fetch_kw_list sample_fetch_keywords = {ILH, { + { "bs.id", smp_fetch_sid, 0, NULL, SMP_T_SINT, SMP_USE_L6REQ }, + { "fs.id", smp_fetch_sid, 0, NULL, SMP_T_STR, SMP_USE_L6RES }, + { /* END */ }, +}}; + +INITCALL1(STG_REGISTER, sample_register_fetches, &sample_fetch_keywords); |