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-rw-r--r--src/vnet/session/session.c564
1 files changed, 137 insertions, 427 deletions
diff --git a/src/vnet/session/session.c b/src/vnet/session/session.c
index 8e2b2616f58..e6cfe7dab3d 100644
--- a/src/vnet/session/session.c
+++ b/src/vnet/session/session.c
@@ -36,15 +36,14 @@ session_manager_main_t session_manager_main;
* Session lookup key; (src-ip, dst-ip, src-port, dst-port, session-type)
* Value: (owner thread index << 32 | session_index);
*/
-static void
-stream_session_table_add_for_tc (u8 sst, transport_connection_t * tc,
- u64 value)
+void
+stream_session_table_add_for_tc (transport_connection_t * tc, u64 value)
{
session_manager_main_t *smm = &session_manager_main;
session_kv4_t kv4;
session_kv6_t kv6;
- switch (sst)
+ switch (tc->proto)
{
case SESSION_TYPE_IP4_UDP:
case SESSION_TYPE_IP4_TCP:
@@ -72,12 +71,12 @@ stream_session_table_add (session_manager_main_t * smm, stream_session_t * s,
tc = tp_vfts[s->session_type].get_connection (s->connection_index,
s->thread_index);
- stream_session_table_add_for_tc (s->session_type, tc, value);
+ stream_session_table_add_for_tc (tc, value);
}
static void
-stream_session_half_open_table_add (u8 sst, transport_connection_t * tc,
- u64 value)
+stream_session_half_open_table_add (session_type_t sst,
+ transport_connection_t * tc, u64 value)
{
session_manager_main_t *smm = &session_manager_main;
session_kv4_t kv4;
@@ -105,14 +104,13 @@ stream_session_half_open_table_add (u8 sst, transport_connection_t * tc,
}
}
-static int
-stream_session_table_del_for_tc (session_manager_main_t * smm, u8 sst,
- transport_connection_t * tc)
+int
+stream_session_table_del_for_tc (transport_connection_t * tc)
{
+ session_manager_main_t *smm = &session_manager_main;
session_kv4_t kv4;
session_kv6_t kv6;
-
- switch (sst)
+ switch (tc->proto)
{
case SESSION_TYPE_IP4_UDP:
case SESSION_TYPE_IP4_TCP:
@@ -141,7 +139,7 @@ stream_session_table_del (session_manager_main_t * smm, stream_session_t * s)
ts = tp_vfts[s->session_type].get_connection (s->connection_index,
s->thread_index);
- return stream_session_table_del_for_tc (smm, s->session_type, ts);
+ return stream_session_table_del_for_tc (ts);
}
static void
@@ -383,7 +381,7 @@ stream_session_lookup_transport6 (ip6_address_t * lcl, ip6_address_t * rmt,
* Allocate vpp event queue (once) per worker thread
*/
void
-vpp_session_event_queue_allocate (session_manager_main_t * smm,
+session_vpp_event_queue_allocate (session_manager_main_t * smm,
u32 thread_index)
{
api_main_t *am = &api_main;
@@ -406,266 +404,24 @@ vpp_session_event_queue_allocate (session_manager_main_t * smm,
}
}
-void
-session_manager_get_segment_info (u32 index, u8 ** name, u32 * size)
-{
- svm_fifo_segment_private_t *s;
- s = svm_fifo_get_segment (index);
- *name = s->h->segment_name;
- *size = s->ssvm.ssvm_size;
-}
-
-always_inline int
-session_manager_add_segment_i (session_manager_main_t * smm,
- session_manager_t * sm,
- u32 segment_size, u8 * segment_name)
-{
- svm_fifo_segment_create_args_t _ca, *ca = &_ca;
- int rv;
-
- memset (ca, 0, sizeof (*ca));
-
- ca->segment_name = (char *) segment_name;
- ca->segment_size = segment_size;
-
- rv = svm_fifo_segment_create (ca);
- if (rv)
- {
- clib_warning ("svm_fifo_segment_create ('%s', %d) failed",
- ca->segment_name, ca->segment_size);
- vec_free (segment_name);
- return -1;
- }
-
- vec_add1 (sm->segment_indices, ca->new_segment_index);
-
- return 0;
-}
-
-static int
-session_manager_add_segment (session_manager_main_t * smm,
- session_manager_t * sm)
-{
- u8 *segment_name;
- svm_fifo_segment_create_args_t _ca, *ca = &_ca;
- u32 add_segment_size;
- u32 default_segment_size = 128 << 10;
-
- memset (ca, 0, sizeof (*ca));
- segment_name = format (0, "%d-%d%c", getpid (),
- smm->unique_segment_name_counter++, 0);
- add_segment_size =
- sm->add_segment_size ? sm->add_segment_size : default_segment_size;
-
- return session_manager_add_segment_i (smm, sm, add_segment_size,
- segment_name);
-}
-
-int
-session_manager_add_first_segment (session_manager_main_t * smm,
- session_manager_t * sm, u32 segment_size,
- u8 ** segment_name)
-{
- svm_fifo_segment_create_args_t _ca, *ca = &_ca;
- memset (ca, 0, sizeof (*ca));
- *segment_name = format (0, "%d-%d%c", getpid (),
- smm->unique_segment_name_counter++, 0);
- return session_manager_add_segment_i (smm, sm, segment_size, *segment_name);
-}
-
-void
-session_manager_del (session_manager_main_t * smm, session_manager_t * sm)
-{
- u32 *deleted_sessions = 0;
- u32 *deleted_thread_indices = 0;
- int i, j;
-
- /* Across all fifo segments used by the server */
- for (j = 0; j < vec_len (sm->segment_indices); j++)
- {
- svm_fifo_segment_private_t *fifo_segment;
- svm_fifo_t **fifos;
- /* Vector of fifos allocated in the segment */
- fifo_segment = svm_fifo_get_segment (sm->segment_indices[j]);
- fifos = (svm_fifo_t **) fifo_segment->h->fifos;
-
- /*
- * Remove any residual sessions from the session lookup table
- * Don't bother deleting the individual fifos, we're going to
- * throw away the fifo segment in a minute.
- */
- for (i = 0; i < vec_len (fifos); i++)
- {
- svm_fifo_t *fifo;
- u32 session_index, thread_index;
- stream_session_t *session;
-
- fifo = fifos[i];
- session_index = fifo->server_session_index;
- thread_index = fifo->server_thread_index;
-
- session = pool_elt_at_index (smm->sessions[thread_index],
- session_index);
-
- /* Add to the deleted_sessions vector (once!) */
- if (!session->is_deleted)
- {
- session->is_deleted = 1;
- vec_add1 (deleted_sessions,
- session - smm->sessions[thread_index]);
- vec_add1 (deleted_thread_indices, thread_index);
- }
- }
-
- for (i = 0; i < vec_len (deleted_sessions); i++)
- {
- stream_session_t *session;
-
- session =
- pool_elt_at_index (smm->sessions[deleted_thread_indices[i]],
- deleted_sessions[i]);
-
- /* Instead of directly removing the session call disconnect */
- stream_session_disconnect (session);
-
- /*
- stream_session_table_del (smm, session);
- pool_put(smm->sessions[deleted_thread_indices[i]], session);
- */
- }
-
- vec_reset_length (deleted_sessions);
- vec_reset_length (deleted_thread_indices);
-
- /* Instead of removing the segment, test when removing the session if
- * the segment can be removed
- */
- /* svm_fifo_segment_delete (fifo_segment); */
- }
-
- vec_free (deleted_sessions);
- vec_free (deleted_thread_indices);
-}
-
-int
-session_manager_allocate_session_fifos (session_manager_main_t * smm,
- session_manager_t * sm,
- svm_fifo_t ** server_rx_fifo,
- svm_fifo_t ** server_tx_fifo,
- u32 * fifo_segment_index,
- u8 * added_a_segment)
-{
- svm_fifo_segment_private_t *fifo_segment;
- u32 fifo_size, default_fifo_size = 1 << 16; /* TODO config */
- int i;
-
- *added_a_segment = 0;
-
- /* Allocate svm fifos */
- ASSERT (vec_len (sm->segment_indices));
-
-again:
- for (i = 0; i < vec_len (sm->segment_indices); i++)
- {
- *fifo_segment_index = sm->segment_indices[i];
- fifo_segment = svm_fifo_get_segment (*fifo_segment_index);
-
- fifo_size = sm->rx_fifo_size;
- fifo_size = (fifo_size == 0) ? default_fifo_size : fifo_size;
- *server_rx_fifo = svm_fifo_segment_alloc_fifo (fifo_segment, fifo_size);
-
- fifo_size = sm->tx_fifo_size;
- fifo_size = (fifo_size == 0) ? default_fifo_size : fifo_size;
- *server_tx_fifo = svm_fifo_segment_alloc_fifo (fifo_segment, fifo_size);
-
- if (*server_rx_fifo == 0)
- {
- /* This would be very odd, but handle it... */
- if (*server_tx_fifo != 0)
- {
- svm_fifo_segment_free_fifo (fifo_segment, *server_tx_fifo);
- *server_tx_fifo = 0;
- }
- continue;
- }
- if (*server_tx_fifo == 0)
- {
- if (*server_rx_fifo != 0)
- {
- svm_fifo_segment_free_fifo (fifo_segment, *server_rx_fifo);
- *server_rx_fifo = 0;
- }
- continue;
- }
- break;
- }
-
- /* See if we're supposed to create another segment */
- if (*server_rx_fifo == 0)
- {
- if (sm->add_segment)
- {
- if (*added_a_segment)
- {
- clib_warning ("added a segment, still cant allocate a fifo");
- return SESSION_ERROR_NEW_SEG_NO_SPACE;
- }
-
- if (session_manager_add_segment (smm, sm))
- return VNET_API_ERROR_URI_FIFO_CREATE_FAILED;
-
- *added_a_segment = 1;
- goto again;
- }
- else
- {
- clib_warning ("No space to allocate fifos!");
- return SESSION_ERROR_NO_SPACE;
- }
- }
- return 0;
-}
-
int
-stream_session_create_i (session_manager_main_t * smm, application_t * app,
- transport_connection_t * tc,
+stream_session_create_i (segment_manager_t * sm, transport_connection_t * tc,
stream_session_t ** ret_s)
{
- int rv;
+ session_manager_main_t *smm = &session_manager_main;
svm_fifo_t *server_rx_fifo = 0, *server_tx_fifo = 0;
u32 fifo_segment_index;
- u32 pool_index, seg_size;
+ u32 pool_index;
stream_session_t *s;
u64 value;
u32 thread_index = tc->thread_index;
- session_manager_t *sm;
- u8 segment_added;
- u8 *seg_name;
-
- sm = session_manager_get (app->session_manager_index);
-
- /* Check the API queue */
- if (app->mode == APP_SERVER && application_api_queue_is_full (app))
- return SESSION_ERROR_API_QUEUE_FULL;
+ int rv;
- if ((rv = session_manager_allocate_session_fifos (smm, sm, &server_rx_fifo,
- &server_tx_fifo,
- &fifo_segment_index,
- &segment_added)))
+ if ((rv = segment_manager_alloc_session_fifos (sm, &server_rx_fifo,
+ &server_tx_fifo,
+ &fifo_segment_index)))
return rv;
- if (segment_added && app->mode == APP_SERVER)
- {
- /* Send an API message to the external server, to map new segment */
- ASSERT (app->cb_fns.add_segment_callback);
-
- session_manager_get_segment_info (fifo_segment_index, &seg_name,
- &seg_size);
- if (app->cb_fns.add_segment_callback (app->api_client_index, seg_name,
- seg_size))
- return VNET_API_ERROR_URI_FIFO_CREATE_FAILED;
- }
-
/* Create the session */
pool_get (smm->sessions[thread_index], s);
memset (s, 0, sizeof (*s));
@@ -682,10 +438,9 @@ stream_session_create_i (session_manager_main_t * smm, application_t * app,
s->server_tx_fifo = server_tx_fifo;
/* Initialize state machine, such as it is... */
- s->session_type = app->session_type;
+ s->session_type = tc->proto;
s->session_state = SESSION_STATE_CONNECTING;
- s->app_index = application_get_index (app);
- s->server_segment_index = fifo_segment_index;
+ s->svm_segment_index = fifo_segment_index;
s->thread_index = thread_index;
s->session_index = pool_index;
@@ -697,7 +452,7 @@ stream_session_create_i (session_manager_main_t * smm, application_t * app,
/* Add to the main lookup table */
value = (((u64) thread_index) << 32) | (u64) s->session_index;
- stream_session_table_add_for_tc (app->session_type, tc, value);
+ stream_session_table_add_for_tc (tc, value);
*ret_s = s;
@@ -881,94 +636,6 @@ session_manager_flush_enqueue_events (u32 thread_index)
return errors;
}
-/*
- * Start listening on server's ip/port pair for requested transport.
- *
- * Creates a 'dummy' stream session with state LISTENING to be used in session
- * lookups, prior to establishing connection. Requests transport to build
- * it's own specific listening connection.
- */
-int
-stream_session_start_listen (u32 server_index, ip46_address_t * ip, u16 port)
-{
- session_manager_main_t *smm = &session_manager_main;
- stream_session_t *s;
- transport_connection_t *tc;
- application_t *srv;
- u32 tci;
-
- srv = application_get (server_index);
-
- pool_get (smm->listen_sessions[srv->session_type], s);
- memset (s, 0, sizeof (*s));
-
- s->session_type = srv->session_type;
- s->session_state = SESSION_STATE_LISTENING;
- s->session_index = s - smm->listen_sessions[srv->session_type];
- s->app_index = srv->index;
-
- /* Transport bind/listen */
- tci = tp_vfts[srv->session_type].bind (s->session_index, ip, port);
-
- /* Attach transport to session */
- s->connection_index = tci;
- tc = tp_vfts[srv->session_type].get_listener (tci);
-
- srv->session_index = s->session_index;
-
- /* Add to the main lookup table */
- stream_session_table_add_for_tc (s->session_type, tc, s->session_index);
-
- return 0;
-}
-
-void
-stream_session_stop_listen (u32 server_index)
-{
- session_manager_main_t *smm = &session_manager_main;
- stream_session_t *listener;
- transport_connection_t *tc;
- application_t *srv;
-
- srv = application_get (server_index);
- listener = pool_elt_at_index (smm->listen_sessions[srv->session_type],
- srv->session_index);
-
- tc = tp_vfts[srv->session_type].get_listener (listener->connection_index);
- stream_session_table_del_for_tc (smm, listener->session_type, tc);
-
- tp_vfts[srv->session_type].unbind (listener->connection_index);
- pool_put (smm->listen_sessions[srv->session_type], listener);
-}
-
-int
-connect_server_add_segment_cb (application_t * ss, char *segment_name,
- u32 segment_size)
-{
- /* Does exactly nothing, but die */
- ASSERT (0);
- return 0;
-}
-
-void
-connects_session_manager_init (session_manager_main_t * smm, u8 session_type)
-{
- session_manager_t *sm;
- u32 connect_fifo_size = 256 << 10; /* Config? */
- u32 default_segment_size = 1 << 20;
-
- pool_get (smm->session_managers, sm);
- memset (sm, 0, sizeof (*sm));
-
- sm->add_segment_size = default_segment_size;
- sm->rx_fifo_size = connect_fifo_size;
- sm->tx_fifo_size = connect_fifo_size;
- sm->add_segment = 1;
-
- session_manager_add_segment (smm, sm);
- smm->connect_manager_index[session_type] = sm - smm->session_managers;
-}
-
void
stream_session_connect_notify (transport_connection_t * tc, u8 sst,
u8 is_fail)
@@ -976,34 +643,36 @@ stream_session_connect_notify (transport_connection_t * tc, u8 sst,
session_manager_main_t *smm = &session_manager_main;
application_t *app;
stream_session_t *new_s = 0;
- u64 value;
+ u64 handle;
+ u32 api_context = 0;
- value = stream_session_half_open_lookup (smm, &tc->lcl_ip, &tc->rmt_ip,
- tc->lcl_port, tc->rmt_port,
- tc->proto);
- if (value == HALF_OPEN_LOOKUP_INVALID_VALUE)
+ handle = stream_session_half_open_lookup (smm, &tc->lcl_ip, &tc->rmt_ip,
+ tc->lcl_port, tc->rmt_port,
+ tc->proto);
+ if (handle == HALF_OPEN_LOOKUP_INVALID_VALUE)
{
clib_warning ("This can't be good!");
return;
}
- app = application_get (value >> 32);
+ /* Get the app's index from the handle we stored when opening connection */
+ app = application_get (handle >> 32);
+ api_context = tc->s_index;
if (!is_fail)
{
- /* Create new session (server segments are allocated if needed) */
- if (stream_session_create_i (smm, app, tc, &new_s))
- return;
+ segment_manager_t *sm;
+ sm = application_get_connect_segment_manager (app);
- app->session_index = stream_session_get_index (new_s);
- app->thread_index = new_s->thread_index;
+ /* Create new session (svm segments are allocated if needed) */
+ if (stream_session_create_i (sm, tc, &new_s))
+ return;
- /* Allocate vpp event queue for this thread if needed */
- vpp_session_event_queue_allocate (smm, tc->thread_index);
+ new_s->app_index = app->index;
}
/* Notify client */
- app->cb_fns.session_connected_callback (app->api_client_index, new_s,
+ app->cb_fns.session_connected_callback (app->index, api_context, new_s,
is_fail);
/* Cleanup session lookup */
@@ -1046,48 +715,13 @@ void
stream_session_delete (stream_session_t * s)
{
session_manager_main_t *smm = vnet_get_session_manager_main ();
- svm_fifo_segment_private_t *fifo_segment;
- application_t *app;
/* Delete from the main lookup table. */
stream_session_table_del (smm, s);
/* Cleanup fifo segments */
- fifo_segment = svm_fifo_get_segment (s->server_segment_index);
- svm_fifo_segment_free_fifo (fifo_segment, s->server_rx_fifo);
- svm_fifo_segment_free_fifo (fifo_segment, s->server_tx_fifo);
-
- app = application_get_if_valid (s->app_index);
-
- /* No app. A possibility: after disconnect application called unbind */
- if (!app)
- return;
-
- if (app->mode == APP_CLIENT)
- {
- /* Cleanup app if client */
- application_del (app);
- }
- else if (app->mode == APP_SERVER)
- {
- session_manager_t *sm;
- svm_fifo_segment_private_t *fifo_segment;
- svm_fifo_t **fifos;
- u32 fifo_index;
-
- /* For server, see if any segments can be removed */
- sm = session_manager_get (app->session_manager_index);
-
- /* Delete fifo */
- fifo_segment = svm_fifo_get_segment (s->server_segment_index);
- fifos = (svm_fifo_t **) fifo_segment->h->fifos;
-
- fifo_index = svm_fifo_segment_index (fifo_segment);
-
- /* Remove segment only if it holds no fifos and not the first */
- if (sm->segment_indices[0] != fifo_index && vec_len (fifos) == 0)
- svm_fifo_segment_delete (fifo_segment);
- }
+ segment_manager_dealloc_fifos (s->svm_segment_index, s->server_rx_fifo,
+ s->server_tx_fifo);
pool_put (smm->sessions[s->thread_index], s);
}
@@ -1134,21 +768,22 @@ int
stream_session_accept (transport_connection_t * tc, u32 listener_index,
u8 sst, u8 notify)
{
- session_manager_main_t *smm = &session_manager_main;
application_t *server;
stream_session_t *s, *listener;
+ segment_manager_t *sm;
int rv;
/* Find the server */
- listener = pool_elt_at_index (smm->listen_sessions[sst], listener_index);
+ listener = listen_session_get (sst, listener_index);
server = application_get (listener->app_index);
- if ((rv = stream_session_create_i (smm, server, tc, &s)))
+ sm = application_get_listen_segment_manager (server, listener);
+ if ((rv = stream_session_create_i (sm, tc, &s)))
return rv;
- /* Allocate vpp event queue for this thread if needed */
- vpp_session_event_queue_allocate (smm, tc->thread_index);
+ s->app_index = server->index;
+ s->listener_index = listener_index;
/* Shoulder-tap the server */
if (notify)
@@ -1159,38 +794,112 @@ stream_session_accept (transport_connection_t * tc, u32 listener_index,
return 0;
}
+/**
+ * Ask transport to open connection to remote transport endpoint.
+ *
+ * Stores handle for matching request with reply since the call can be
+ * asynchronous. For instance, for TCP the 3-way handshake must complete
+ * before reply comes. Session is only created once connection is established.
+ *
+ * @param app_index Index of the application requesting the connect
+ * @param st Session type requested.
+ * @param tep Remote transport endpoint
+ * @param res Resulting transport connection .
+ */
int
-stream_session_open (u8 sst, ip46_address_t * addr, u16 port_host_byte_order,
- u32 app_index)
+stream_session_open (u32 app_index, session_type_t st,
+ transport_endpoint_t * tep,
+ transport_connection_t ** res)
{
transport_connection_t *tc;
- u32 tci;
- u64 value;
int rv;
+ u64 handle;
- /* Ask transport to open connection */
- rv = tp_vfts[sst].open (addr, port_host_byte_order);
+ rv = tp_vfts[st].open (&tep->ip, tep->port);
if (rv < 0)
{
clib_warning ("Transport failed to open connection.");
return VNET_API_ERROR_SESSION_CONNECT_FAIL;
}
- tci = rv;
+ tc = tp_vfts[st].get_half_open ((u32) rv);
- /* Get transport connection */
- tc = tp_vfts[sst].get_half_open (tci);
-
- /* Store api_client_index and transport connection index */
- value = (((u64) app_index) << 32) | (u64) tc->c_index;
+ /* Save app and tc index. The latter is needed to help establish the
+ * connection while the former is needed when the connect notify comes
+ * and we have to notify the external app */
+ handle = (((u64) app_index) << 32) | (u64) tc->c_index;
/* Add to the half-open lookup table */
- stream_session_half_open_table_add (sst, tc, value);
+ stream_session_half_open_table_add (st, tc, handle);
+
+ *res = tc;
+
+ return 0;
+}
+
+/**
+ * Ask transport to listen on local transport endpoint.
+ *
+ * @param s Session for which listen will be called. Note that unlike
+ * established sessions, listen sessions are not associated to a
+ * thread.
+ * @param tep Local endpoint to be listened on.
+ */
+int
+stream_session_listen (stream_session_t * s, transport_endpoint_t * tep)
+{
+ transport_connection_t *tc;
+ u32 tci;
+
+ /* Transport bind/listen */
+ tci = tp_vfts[s->session_type].bind (s->session_index, &tep->ip, tep->port);
+
+ if (tci == (u32) ~ 0)
+ return -1;
+
+ /* Attach transport to session */
+ s->connection_index = tci;
+ tc = tp_vfts[s->session_type].get_listener (tci);
+
+ /* Weird but handle it ... */
+ if (tc == 0)
+ return -1;
+
+ /* Add to the main lookup table */
+ stream_session_table_add_for_tc (tc, s->session_index);
return 0;
}
/**
+ * Ask transport to stop listening on local transport endpoint.
+ *
+ * @param s Session to stop listening on. It must be in state LISTENING.
+ */
+int
+stream_session_stop_listen (stream_session_t * s)
+{
+ transport_connection_t *tc;
+
+ if (s->session_state != SESSION_STATE_LISTENING)
+ {
+ clib_warning ("not a listening session");
+ return -1;
+ }
+
+ tc = tp_vfts[s->session_type].get_listener (s->connection_index);
+ if (!tc)
+ {
+ clib_warning ("no transport");
+ return VNET_API_ERROR_ADDRESS_NOT_IN_USE;
+ }
+
+ stream_session_table_del_for_tc (tc);
+ tp_vfts[s->session_type].unbind (s->connection_index);
+ return 0;
+}
+
+/**
* Disconnect session and propagate to transport. This should eventually
* result in a delete notification that allows us to cleanup session state.
* Called for both active/passive disconnects.
@@ -1297,6 +1006,10 @@ session_manager_main_enable (vlib_main_t * vm)
vec_validate (smm->last_event_poll_by_thread, num_threads - 1);
#endif
+ /* Allocate vpp event queues */
+ for (i = 0; i < vec_len (smm->vpp_event_queues); i++)
+ session_vpp_event_queue_allocate (smm, i);
+
/* $$$$ preallocate hack config parameter */
for (i = 0; i < 200000; i++)
{
@@ -1322,9 +1035,6 @@ session_manager_main_enable (vlib_main_t * vm)
200000 /* $$$$ config parameter nbuckets */ ,
(64 << 20) /*$$$ config parameter table size */ );
- for (i = 0; i < SESSION_N_TYPES; i++)
- smm->connect_manager_index[i] = INVALID_INDEX;
-
smm->is_enabled = 1;
/* Enable TCP transport */