/*
 * Copyright (c) 2017-2019 Cisco and/or its affiliates.
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at:
 *
 *     http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

#ifndef SRC_VNET_SESSION_APPLICATION_H_
#define SRC_VNET_SESSION_APPLICATION_H_

#include <vnet/session/application_interface.h>
#include <vnet/session/application_namespace.h>
#include <vnet/session/session_types.h>
#include <vnet/session/segment_manager.h>

#define APP_DEBUG 0

#if APP_DEBUG > 0
#define APP_DBG(_fmt, _args...) clib_warning (_fmt, ##_args)
#else
#define APP_DBG(_fmt, _args...)
#endif

typedef struct app_wrk_postponed_msg_
{
  u32 len;
  u8 event_type;
  u8 ring;
  u8 is_sapi;
  int fd;
  u8 data[SESSION_CTRL_MSG_TX_MAX_SIZE];
} app_wrk_postponed_msg_t;

typedef struct app_worker_
{
  CLIB_CACHE_LINE_ALIGN_MARK (cacheline0);

  /** Worker index in global worker pool*/
  u32 wrk_index;

  /** Worker index in app's map pool */
  u32 wrk_map_index;

  /** Index of owning app */
  u32 app_index;

  /** Application listens for events on this svm queue */
  svm_msg_q_t *event_queue;

  /**
   * Segment manager used for outgoing connects issued by the app. By
   * convention this is the first segment manager allocated by the worker
   * so it's also the one that holds the first segment with the app's
   * message queue in it.
   */
  u32 connects_seg_manager;

  /** Lookup tables for listeners. Value is segment manager index */
  uword *listeners_table;

  /** API index for the worker. Needed for multi-process apps */
  u32 api_client_index;

  /** Set if mq is congested */
  u8 mq_congested;

  u8 app_is_builtin;

  /** Pool of half-open session handles. Tracked in case worker detaches */
  session_handle_t *half_open_table;

  /* Per vpp worker fifos of events for app worker */
  session_event_t **wrk_evts;

  /* Vector of vpp workers mq congestion flags */
  u8 *wrk_mq_congested;

  /** Protects detached seg managers */
  clib_spinlock_t detached_seg_managers_lock;

  /** Vector of detached listener segment managers */
  u32 *detached_seg_managers;
} app_worker_t;

typedef struct app_worker_map_
{
  u32 wrk_index;
} app_worker_map_t;

typedef struct app_listener_
{
  clib_bitmap_t *workers;	/**< workers accepting connections */
  u32 accept_rotor;		/**< last worker to accept a connection */
  u32 al_index;			/**< app listener index in app pool */
  u32 app_index;		/**< owning app index */
  u32 local_index;		/**< local listening session index */
  u32 session_index;		/**< global listening session index */
  session_handle_t ls_handle;	/**< session handle of the local or global
				     listening session that also identifies
				     the app listener */
  u32 *cl_listeners;		/**< vector that maps app workers to their
				     cl sessions with fifos */
} app_listener_t;

typedef enum app_rx_mq_flags_
{
  APP_RX_MQ_F_PENDING = 1 << 0,
  APP_RX_MQ_F_POSTPONED = 1 << 1,
} app_rx_mq_flags_t;

typedef struct app_rx_mq_elt_
{
  struct app_rx_mq_elt_ *next;
  struct app_rx_mq_elt_ *prev;
  svm_msg_q_t *mq;
  uword file_index;
  u32 app_index;
  u8 flags;
} app_rx_mq_elt_t;

typedef struct application_
{
  /** App index in app pool */
  u32 app_index;

  /** Flags */
  u32 flags;

  /** Callbacks: shoulder-taps for the server/client */
  session_cb_vft_t cb_fns;

  /** Segment manager properties. Shared by all segment managers */
  segment_manager_props_t sm_properties;

  /** Pool of mappings that keep track of workers associated to this app */
  app_worker_map_t *worker_maps;

  /** Name registered by builtin apps */
  u8 *name;

  /** Namespace the application belongs to */
  u32 ns_index;

  u16 proxied_transports;

  /** Preferred tls engine */
  u8 tls_engine;

  /** quic initialization vector */
  char quic_iv[17];
  u8 quic_iv_set;

  /** Segment where rx mqs were allocated */
  fifo_segment_t rx_mqs_segment;

  /**
   * Fixed vector of rx mqs that can be a part of pending_rx_mqs
   * linked list maintained by the app sublayer for each worker
   */
  app_rx_mq_elt_t *rx_mqs;
} application_t;

typedef struct app_rx_mq_handle_
{
  union
  {
    struct
    {
      u32 app_index;
      u32 thread_index;
    };
    u64 as_u64;
  };
} __attribute__ ((aligned (sizeof (u64)))) app_rx_mq_handle_t;

/**
 * App sublayer per vpp worker state
 */
typedef struct asl_wrk_
{
  /** Linked list of mqs with pending messages */
  app_rx_mq_elt_t *pending_rx_mqs;
} appsl_wrk_t;

typedef struct app_main_
{
  /**
   * Pool from which we allocate all applications
   */
  application_t *app_pool;

  /** Pool of app listeners */
  app_listener_t *listeners;

  /**
   * Hash table of apps by api client index
   */
  uword *app_by_api_client_index;

  /**
   * Hash table of builtin apps by name
   */
  uword *app_by_name;

  /**
   * Pool from which we allocate certificates (key, cert)
   */
  app_cert_key_pair_t *cert_key_pair_store;

  /*
   * Last registered crypto engine type
   */
  crypto_engine_type_t last_crypto_engine;

  /**
   * App sublayer per-worker state
   */
  appsl_wrk_t *wrk;
} app_main_t;

typedef struct app_init_args_
{
#define _(_type, _name) _type _name;
  foreach_app_init_args
#undef _
} app_init_args_t;

typedef struct _vnet_app_worker_add_del_args
{
  u32 app_index;		/**< App for which a new worker is requested */
  u32 wrk_map_index;		/**< Index to delete or return value if add */
  u32 api_client_index;		/**< Binary API client index */
  ssvm_private_t *segment;	/**< First segment in segment manager */
  u64 segment_handle;		/**< Handle for the segment */
  svm_msg_q_t *evt_q;		/**< Worker message queue */
  u8 is_add;			/**< Flag set if addition */
} vnet_app_worker_add_del_args_t;

#define APP_INVALID_INDEX ((u32)~0)
#define APP_NS_INVALID_INDEX ((u32)~0)
#define APP_INVALID_SEGMENT_MANAGER_INDEX ((u32) ~0)

app_listener_t *app_listener_get (u32 al_index);
int app_listener_alloc_and_init (application_t * app,
				 session_endpoint_cfg_t * sep,
				 app_listener_t ** listener);
void app_listener_cleanup (app_listener_t * app_listener);
session_handle_t app_listener_handle (app_listener_t * app_listener);
app_listener_t *app_listener_lookup (application_t * app,
				     session_endpoint_cfg_t * sep);
session_t *app_listener_select_wrk_cl_session (session_t *ls,
					       session_dgram_hdr_t *hdr);

/**
 * Get app listener handle for listening session
 *
 * For a given listening session, this can return either the session
 * handle of the app listener associated to the listening session or,
 * if no such app listener exists, the session's handle
 *
 * @param ls		listening session
 * @return		app listener or listening session handle
 */
session_handle_t app_listen_session_handle (session_t * ls);
/**
 * Get app listener for listener session handle
 *
 * Should only be called on handles that have an app listener, i.e.,
 * were obtained at the end of a @ref vnet_listen call.
 *
 * @param handle	handle of the app listener. This is the handle of
 * 			either the global or local listener
 * @return		pointer to app listener or 0
 */
app_listener_t *app_listener_get_w_handle (session_handle_t handle);
session_t *app_listener_get_session (app_listener_t * al);
session_t *app_listener_get_local_session (app_listener_t * al);
session_t *app_listener_get_wrk_cl_session (app_listener_t *al, u32 wrk_index);

application_t *application_get (u32 index);
application_t *application_get_if_valid (u32 index);
application_t *application_lookup (u32 api_client_index);
application_t *application_lookup_name (const u8 * name);
app_worker_t *application_get_worker (application_t * app, u32 wrk_index);
app_worker_t *application_get_default_worker (application_t * app);
app_worker_t *application_listener_select_worker (session_t * ls);
int application_change_listener_owner (session_t * s, app_worker_t * app_wrk);
int application_is_proxy (application_t * app);
int application_is_builtin (application_t * app);
int application_is_builtin_proxy (application_t * app);
u32 application_session_table (application_t * app, u8 fib_proto);
u32 application_local_session_table (application_t * app);
const u8 *application_name_from_index (u32 app_or_wrk);
u8 application_has_local_scope (application_t * app);
u8 application_has_global_scope (application_t * app);
void application_setup_proxy (application_t * app);
void application_remove_proxy (application_t * app);
void application_namespace_cleanup (app_namespace_t *app_ns);
int application_original_dst_is_enabled (application_t *app);

segment_manager_props_t *application_get_segment_manager_properties (u32
								     app_index);

segment_manager_props_t
  * application_segment_manager_properties (application_t * app);

svm_msg_q_t *application_rx_mq_get (application_t *app, u32 mq_index);
u8 application_use_private_rx_mqs (void);
fifo_segment_t *application_get_rx_mqs_segment (application_t *app);
void application_enable_rx_mqs_nodes (u8 is_en);

/*
 * App worker
 */

always_inline u8
app_worker_mq_is_congested (app_worker_t *app_wrk)
{
  return app_wrk->mq_congested > 0;
}

app_worker_t *app_worker_alloc (application_t * app);
int application_alloc_worker_and_init (application_t * app,
				       app_worker_t ** wrk);
app_worker_t *app_worker_get (u32 wrk_index);
app_worker_t *app_worker_get_if_valid (u32 wrk_index);
application_t *app_worker_get_app (u32 wrk_index);
int app_worker_own_session (app_worker_t * app_wrk, session_t * s);
void app_worker_free (app_worker_t * app_wrk);
int app_worker_connect_session (app_worker_t *app, session_endpoint_cfg_t *sep,
				session_handle_t *rsh);
session_error_t app_worker_start_listen (app_worker_t *app_wrk,
					 app_listener_t *lstnr);
int app_worker_stop_listen (app_worker_t * app_wrk, app_listener_t * al);
int app_worker_init_accepted (session_t * s);
int app_worker_listened_notify (app_worker_t *app_wrk, session_handle_t alsh,
				u32 opaque, session_error_t err);
int app_worker_unlisten_reply (app_worker_t *app_wrk, session_handle_t sh,
			       u32 opaque, session_error_t err);
int app_worker_accept_notify (app_worker_t * app_wrk, session_t * s);
int app_worker_init_connected (app_worker_t * app_wrk, session_t * s);
int app_worker_connect_notify (app_worker_t * app_wrk, session_t * s,
			       session_error_t err, u32 opaque);
int app_worker_add_half_open (app_worker_t *app_wrk, session_handle_t sh);
int app_worker_del_half_open (app_worker_t *app_wrk, session_t *s);
int app_worker_close_notify (app_worker_t * app_wrk, session_t * s);
int app_worker_transport_closed_notify (app_worker_t * app_wrk,
					session_t * s);
int app_worker_reset_notify (app_worker_t * app_wrk, session_t * s);
int app_worker_cleanup_notify (app_worker_t * app_wrk, session_t * s,
			       session_cleanup_ntf_t ntf);
int app_worker_cleanup_notify_custom (app_worker_t *app_wrk, session_t *s,
				      session_cleanup_ntf_t ntf,
				      void (*cleanup_cb) (session_t *s));
int app_worker_migrate_notify (app_worker_t * app_wrk, session_t * s,
			       session_handle_t new_sh);
int app_worker_rx_notify (app_worker_t *app_wrk, session_t *s);
int app_worker_session_fifo_tuning (app_worker_t * app_wrk, session_t * s,
				    svm_fifo_t * f,
				    session_ft_action_t act, u32 len);
void app_worker_add_event (app_worker_t *app_wrk, session_t *s,
			   session_evt_type_t evt_type);
void app_worker_add_event_custom (app_worker_t *app_wrk, u32 thread_index,
				  session_event_t *evt);
int app_wrk_flush_wrk_events (app_worker_t *app_wrk, u32 thread_index);
void app_worker_del_all_events (app_worker_t *app_wrk);
segment_manager_t *app_worker_get_listen_segment_manager (app_worker_t *,
							  session_t *);
segment_manager_t *app_worker_get_connect_segment_manager (app_worker_t *);
int app_worker_add_segment_notify (app_worker_t * app_wrk,
				   u64 segment_handle);
int app_worker_del_segment_notify (app_worker_t * app_wrk,
				   u64 segment_handle);
u32 app_worker_n_listeners (app_worker_t * app);
session_t *app_worker_first_listener (app_worker_t * app,
				      u8 fib_proto, u8 transport_proto);
void app_wrk_send_ctrl_evt_fd (app_worker_t *app_wrk, u8 evt_type, void *msg,
			       u32 msg_len, int fd);
void app_wrk_send_ctrl_evt (app_worker_t *app_wrk, u8 evt_type, void *msg,
			    u32 msg_len);
u8 app_worker_mq_wrk_is_congested (app_worker_t *app_wrk, u32 thread_index);
void app_worker_set_mq_wrk_congested (app_worker_t *app_wrk, u32 thread_index);
void app_worker_unset_wrk_mq_congested (app_worker_t *app_wrk,
					u32 thread_index);
session_t *app_worker_proxy_listener (app_worker_t * app, u8 fib_proto,
				      u8 transport_proto);
void app_worker_del_detached_sm (app_worker_t * app_wrk, u32 sm_index);
u8 *format_app_worker (u8 * s, va_list * args);
u8 *format_app_worker_listener (u8 * s, va_list * args);
u8 *format_crypto_engine (u8 * s, va_list * args);
u8 *format_crypto_context (u8 * s, va_list * args);
void app_worker_format_connects (app_worker_t * app_wrk, int verbose);
session_error_t vnet_app_worker_add_del (vnet_app_worker_add_del_args_t *a);

uword unformat_application_proto (unformat_input_t * input, va_list * args);

app_cert_key_pair_t *app_cert_key_pair_get (u32 index);
app_cert_key_pair_t *app_cert_key_pair_get_if_valid (u32 index);
app_cert_key_pair_t *app_cert_key_pair_get_default ();

void sapi_socket_close_w_handle (u32 api_handle);

crypto_engine_type_t app_crypto_engine_type_add (void);
u8 app_crypto_engine_n_types (void);

static inline u8
app_worker_application_is_builtin (app_worker_t *app_wrk)
{
  return app_wrk->app_is_builtin;
}

#endif /* SRC_VNET_SESSION_APPLICATION_H_ */

/*
 * fd.io coding-style-patch-verification: ON
 *
 * Local Variables:
 * eval: (c-set-style "gnu")
 * End:
 */