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22 * @file util/service_new.c
23 * @brief functions related to starting services (redesign)
24 * @author Christian Grothoff
27 #include "gnunet_util_lib.h"
28 #include "gnunet_protocols.h"
29 #include "gnunet_constants.h"
30 #include "gnunet_resolver_service.h"
34 * Information the service tracks per listen operation.
36 struct ServiceListenContext
42 struct ServiceListenContext *next;
47 struct ServiceListenContext *prev;
50 * Service this listen context belongs to.
52 struct GNUNET_SERVICE_Handle *sh;
55 * Socket we are listening on.
57 struct GNUNET_NETWORK_Handle *listen_socket;
60 * Task scheduled to do the listening.
62 struct GNUNET_SCHEDULER_Task *listen_task;
68 * Handle to a service.
70 struct GNUNET_SERVICE_Handle
75 const struct GNUNET_CONFIGURATION_Handle *cfg;
78 * Name of our service.
80 const char *service_name;
83 * Main service-specific task to run.
85 GNUNET_SERVICE_InitCallback service_init_cb;
88 * Function to call when clients connect.
90 GNUNET_SERVICE_ConnectHandler connect_cb;
93 * Function to call when clients disconnect / are disconnected.
95 GNUNET_SERVICE_DisconnectHandler disconnect_cb;
98 * Closure for @e service_init_cb, @e connect_cb, @e disconnect_cb.
103 * DLL of listen sockets used to accept new connections.
105 struct ServiceListenContext *slc_head;
108 * DLL of listen sockets used to accept new connections.
110 struct ServiceListenContext *slc_tail;
113 * Our clients, kept in a DLL.
115 struct GNUNET_SERVICE_Client *clients_head;
118 * Our clients, kept in a DLL.
120 struct GNUNET_SERVICE_Client *clients_tail;
123 * Message handlers to use for all clients.
125 const struct GNUNET_MQ_MessageHandler *handlers;
128 * Closure for @e task.
133 * IPv4 addresses that are not allowed to connect.
135 struct GNUNET_STRINGS_IPv4NetworkPolicy *v4_denied;
138 * IPv6 addresses that are not allowed to connect.
140 struct GNUNET_STRINGS_IPv6NetworkPolicy *v6_denied;
143 * IPv4 addresses that are allowed to connect (if not
144 * set, all are allowed).
146 struct GNUNET_STRINGS_IPv4NetworkPolicy *v4_allowed;
149 * IPv6 addresses that are allowed to connect (if not
150 * set, all are allowed).
152 struct GNUNET_STRINGS_IPv6NetworkPolicy *v6_allowed;
155 * Do we require a matching UID for UNIX domain socket connections?
156 * #GNUNET_NO means that the UID does not have to match (however,
157 * @e match_gid may still impose other access control checks).
162 * Do we require a matching GID for UNIX domain socket connections?
163 * Ignored if @e match_uid is #GNUNET_YES. Note that this is about
164 * checking that the client's UID is in our group OR that the
165 * client's GID is our GID. If both "match_gid" and @e match_uid are
166 * #GNUNET_NO, all users on the local system have access.
171 * Set to #GNUNET_YES if we got a shutdown signal and terminate
172 * the service if #have_non_monitor_clients() returns #GNUNET_YES.
179 enum GNUNET_SERVICE_Options options;
185 * Handle to a client that is connected to a service.
187 struct GNUNET_SERVICE_Client
193 struct GNUNET_SERVICE_Client *next;
198 struct GNUNET_SERVICE_Client *prev;
201 * Server that this client belongs to.
203 struct GNUNET_SERVER_Handle *sh;
206 * Socket of this client.
208 struct GNUNET_NETWORK_Handle *sock;
211 * Message queue for the client.
213 struct GNUNET_MQ_Handle *mq;
216 * Task that warns about missing calls to
217 * #GNUNET_SERVICE_client_continue().
219 struct GNUNET_SCHEDULER_Task *warn_task;
222 * User context value, value returned from
223 * the connect callback.
228 * Persist the file handle for this client no matter what happens,
229 * force the OS to close once the process actually dies. Should only
230 * be used in special cases!
235 * Is this client a 'monitor' client that should not be counted
236 * when deciding on destroying the server during soft shutdown?
237 * (see also #GNUNET_SERVICE_start)
242 * Type of last message processed (for warn_no_receive_done).
249 * Check if any of the clients we have left are unrelated to
252 * @param sh service to check clients for
253 * @return #GNUNET_YES if we have non-monitoring clients left
256 have_non_monitor_clients (struct GNUNET_SERVICE_Handle *sh)
258 struct GNUNET_SERVICE_Client *client;
260 for (client = sh->clients_head;NULL != client; client = client->next)
262 if (client->is_monitor)
271 * Shutdown task triggered when a service should be terminated.
272 * This considers active clients and the service options to see
273 * how this specific service is to be terminated, and depending
274 * on this proceeds with the shutdown logic.
276 * @param cls our `struct GNUNET_SERVICE_Handle`
279 service_main (void *cls)
281 struct GNUNET_SERVICE_Handle *sh = cls;
282 struct GNUNET_SERVICE_Client *client;
287 case GNUNET_SERVICE_OPTION_NONE:
288 GNUNET_SERVICE_shutdown (sh);
290 case GNUNET_SERVICE_OPTION_MANUAL_SHUTDOWN:
291 /* This task should never be run if we are using
292 the manual shutdown. */
295 case GNUNET_SERVICE_OPTION_SOFT_SHUTDOWN:
296 sh->got_shutdown = GNUNET_YES;
297 GNUNET_SERVICE_suspend (sh);
298 if (GNUNET_NO == have_non_monitor_clients (sh))
299 GNUNET_SERVICE_shutdown (sh);
306 * First task run by any service. Initializes our shutdown task,
307 * starts the listening operation on our listen sockets and launches
308 * the custom logic of the application service.
310 * @param cls our `struct GNUNET_SERVICE_Handle`
313 service_main (void *cls)
315 struct GNUNET_SERVICE_Handle *sh = cls;
317 if (GNUNET_SERVICE_OPTION_MANUAL_SHUTDOWN != sh->options)
318 GNUNET_SCHEDULER_add_shutdown (&service_shutdown,
320 GNUNET_SERVICE_resume (sh);
321 sh->service_init_cb (sh->cb_cls,
328 * Creates the "main" function for a GNUnet service. You
329 * should almost always use the #GNUNET_SERVICE_MAIN macro
330 * instead of calling this function directly (except
331 * for ARM, which should call this function directly).
333 * The function will launch the service with the name @a service_name
334 * using the @a service_options to configure its shutdown
335 * behavior. Once the service is ready, the @a init_cb will be called
336 * for service-specific initialization. @a init_cb will be given the
337 * service handler which can be used to control the service's
338 * availability. When clients connect or disconnect, the respective
339 * @a connect_cb or @a disconnect_cb functions will be called. For
340 * messages received from the clients, the respective @a handlers will
341 * be invoked; for the closure of the handlers we use the return value
342 * from the @a connect_cb invocation of the respective client.
344 * Each handler MUST call #GNUNET_SERVICE_client_continue() after each
345 * message to receive further messages from this client. If
346 * #GNUNET_SERVICE_client_continue() is not called within a short
347 * time, a warning will be logged. If delays are expected, services
348 * should call #GNUNET_SERVICE_client_disable_continue_warning() to
349 * disable the warning.
351 * Clients sending invalid messages (based on @a handlers) will be
352 * dropped. Additionally, clients can be dropped at any time using
353 * #GNUNET_SERVICE_client_drop().
355 * @param argc number of command-line arguments in @a argv
356 * @param argv array of command-line arguments
357 * @param service_name name of the service to run
358 * @param options options controlling shutdown of the service
359 * @param service_init_cb function to call once the service is ready
360 * @param connect_cb function to call whenever a client connects
361 * @param disconnect_cb function to call whenever a client disconnects
362 * @param cls closure argument for @a service_init_cb, @a connect_cb and @a disconnect_cb
363 * @param handlers NULL-terminated array of message handlers for the service,
364 * the closure will be set to the value returned by
365 * the @a connect_cb for the respective connection
366 * @return 0 on success, non-zero on error
369 GNUNET_SERVICE_ruN_ (int argc,
371 const char *service_name,
372 enum GNUNET_SERVICE_Options options,
373 GNUNET_SERVICE_InitCallback service_init_cb,
374 GNUNET_SERVICE_ConnectHandler connect_cb,
375 GNUNET_SERVICE_DisconnectHandler disconnect_cb,
377 const struct GNUNET_MQ_MessageHandler *handlers)
379 struct GNUNET_SERVICE_Handle sh;
381 // FIXME: setup (parse command line, configuration, init sh)
382 GNUNET_SCHEDULER_run (&service_main,
390 * Suspend accepting connections from the listen socket temporarily.
391 * Resume activity using #GNUNET_SERVICE_resume.
393 * @param sh service to stop accepting connections.
396 GNUNET_SERVICE_suspend (struct GNUNET_SERVICE_Handle *sh)
398 struct ServiceListenContext *slc;
400 for (slc = slc_head; NULL != slc; slc = slc->next)
402 if (NULL != slc->listen_task)
404 GNUNET_SCHEDULER_cancel (slc->listen_task);
405 slc->listen_task = NULL;
412 * We have successfully accepted a connection from a client. Now
413 * setup the client (with the scheduler) and tell the application.
415 * @param sh service that accepted the client
416 * @param sock socket associated with the client
419 start_client (struct GNUNET_SERVICE_Handle *sh,
420 struct GNUNET_NETWORK_Handle *csock)
422 struct GNUNET_SERVICE_Client *client;
424 client = GNUNET_new (struct GNUNET_SERVICE_Client);
425 GNUNET_CONTAINER_DLL_insert (sh->clients_head,
429 client->sock = csock;
430 client->mq = NULL; // FIXME!
431 client->user_context = sh->connect_cb (sh->cb_cls,
438 * We have a client. Accept the incoming socket(s) (and reschedule
441 * @param cls the `struct ServiceListenContext` of the ready listen socket
444 accept_client (void *cls)
446 struct ServiceListenContext *slc = cls;
448 slc->listen_task = NULL;
451 struct GNUNET_NETWORK_Handle *sock;
452 struct sockaddr_in *v4;
453 struct sockaddr_in6 *v6;
454 struct sockaddr_storage sa;
458 addrlen = sizeof (sa);
459 sock = GNUNET_NETWORK_socket_accept (slc->listen_socket,
460 (struct sockaddr *) &sa,
464 switch (sa.sa_family)
467 GNUNET_assert (addrlen == sizeof (struct sockaddr_in));
468 v4 = (const struct sockaddr_in *) addr;
469 ok = ( ( (NULL == sh->v4_allowed) ||
470 (check_ipv4_listed (sh->v4_allowed,
472 ( (NULL == sh->v4_denied) ||
473 (! check_ipv4_listed (sh->v4_denied,
477 GNUNET_assert (addrlen == sizeof (struct sockaddr_in6));
478 v6 = (const struct sockaddr_in6 *) addr;
479 ok = ( ( (NULL == sh->v6_allowed) ||
480 (check_ipv6_listed (sh->v6_allowed,
482 ( (NULL == sh->v6_denied) ||
483 (! check_ipv6_listed (sh->v6_denied,
484 &i6->sin6_addr)) ) );
488 ok = GNUNET_OK; /* controlled using file-system ACL now */
492 LOG (GNUNET_ERROR_TYPE_WARNING,
493 _("Unknown address family %d\n"),
495 return GNUNET_SYSERR;
499 LOG (GNUNET_ERROR_TYPE_DEBUG,
500 "Service rejected incoming connection from %s due to policy.\n",
501 GNUNET_a2s ((const struct sockaddr *) &sa,
503 GNUNET_NETWORK_socket_close (sock);
506 LOG (GNUNET_ERROR_TYPE_DEBUG,
507 "Service accepted incoming connection from %s.\n",
508 GNUNET_a2s ((const struct sockaddr *) &sa,
510 start_client (slc->sh,
513 slc->listen_task = GNUNET_SCHEDULER_add_read (slc->listen_socket,
520 * Resume accepting connections from the listen socket.
522 * @param sh service to resume accepting connections.
525 GNUNET_SERVICE_resume (struct GNUNET_SERVICE_Handle *sh)
527 struct ServiceListenContext *slc;
529 for (slc = slc_head; NULL != slc; slc = slc->next)
531 GNUNET_assert (NULL == slc->listen_task);
532 slc->listen_task = GNUNET_SCHEDULER_add_read (slc->listen_socket,
540 * Continue receiving further messages from the given client.
541 * Must be called after each message received.
543 * @param c the client to continue receiving from
546 GNUNET_SERVICE_client_continue (struct GNUNET_SERVICE_Client *c)
548 GNUNET_break (0); // not implemented
553 * Disable the warning the server issues if a message is not
554 * acknowledged in a timely fashion. Use this call if a client is
555 * intentionally delayed for a while. Only applies to the current
558 * @param c client for which to disable the warning
561 GNUNET_SERVICE_client_disable_continue_warning (struct GNUNET_SERVICE_Client *c)
563 GNUNET_break (NULL != c->warn_task);
564 if (NULL != c->warn_task)
566 GNUNET_SCHEDULER_cancel (c->warn_task);
573 * Ask the server to disconnect from the given client. This is the
574 * same as returning #GNUNET_SYSERR within the check procedure when
575 * handling a message, wexcept that it allows dropping of a client even
576 * when not handling a message from that client. The `disconnect_cb`
577 * will be called on @a c even if the application closes the connection
578 * using this function.
580 * @param c client to disconnect now
583 GNUNET_SERVICE_client_drop (struct GNUNET_SERVICE_Client *c)
585 struct GNUNET_SERVICE_Handle *sh = c->sh;
587 GNUNET_CONTAINER_DLL_remove (sh->clients_head,
590 sh->disconnect_cb (sh->cb_cls,
593 if (NULL != c->warn_task)
595 GNUNET_SCHEDULER_cancel (c->warn_task);
598 GNUNET_MQ_destroy (c->mq);
599 if (GNUNET_NO == c->persist)
601 GNUNET_NETWORK_socket_close (c->sock);
605 GNUNET_NETWORK_socket_free_memory_only_ (c->sock);
608 if ( (GNUNET_YES == sh->got_shutdown) &&
609 (GNUNET_NO == have_non_monitor_clients (sh)) )
610 GNUNET_SERVICE_shutdown (sh);
615 * Explicitly stops the service.
617 * @param sh server to shutdown
620 GNUNET_SERVICE_shutdown (struct GNUNET_SERVICE_Handle *sh)
622 struct GNUNET_SERVICE_Client *client;
624 GNUNET_SERVICE_suspend (sh);
625 sh->got_shutdown = GNUNET_NO;
626 while (NULL != (client = sh->clients_head))
627 GNUNET_SERVICE_client_drop (client);
632 * Set the 'monitor' flag on this client. Clients which have been
633 * marked as 'monitors' won't prevent the server from shutting down
634 * once #GNUNET_SERVICE_stop_listening() has been invoked. The idea is
635 * that for "normal" clients we likely want to allow them to process
636 * their requests; however, monitor-clients are likely to 'never'
637 * disconnect during shutdown and thus will not be considered when
638 * determining if the server should continue to exist after
639 * shutdown has been triggered.
641 * @param c client to mark as a monitor
644 GNUNET_SERVICE_client_mark_monitor (struct GNUNET_SERVICE_Client *c)
646 c->is_monitor = GNUNET_YES;
647 if ( (GNUNET_YES == sh->got_shutdown) &&
648 (GNUNET_NO == have_non_monitor_clients (sh)) )
649 GNUNET_SERVICE_shutdown (sh);
654 * Set the persist option on this client. Indicates that the
655 * underlying socket or fd should never really be closed. Used for
656 * indicating process death.
658 * @param c client to persist the socket (never to be closed)
661 GNUNET_SERVICE_client_persist (struct GNUNET_SERVICE_Client *c)
663 c->persist = GNUNET_YES;
667 /* end of service_new.c */