/**
* @file include/gnunet_social_service.h
- * @brief Social service; implements social functionality using the PSYC service
- * @author tg
+ * @brief Social service; implements social functionality using the PSYC service.
+ * @author Gabor X Toth
+ * @author Christian Grothoff
*/
#ifndef GNUNET_SOCIAL_SERVICE_H
#define GNUNET_SOCIAL_SERVICE_H
#endif
#include "gnunet_util_lib.h"
+#include "gnunet_psyc_lib.h"
#include "gnunet_psyc_service.h"
+#include "gnunet_multicast_service.h"
+
/**
* Version number of GNUnet Social API.
*/
#define GNUNET_SOCIAL_VERSION 0x00000000
+
+/**
+ * Handle for another user (who is likely pseudonymous) in the network.
+ */
+struct GNUNET_SOCIAL_Nym;
+
+/**
+ * Handle for a place where social interactions happen.
+ */
+struct GNUNET_SOCIAL_Place;
+
+/**
+ * Handle for a place that one of our egos hosts.
+ */
+struct GNUNET_SOCIAL_Home;
+
+/**
+ * Handle to an implementation of try-and-slice.
+ */
+struct GNUNET_SOCIAL_Slicer;
+
+
+/**
+ * Method called from SOCIAL upon receiving a message indicating a call
+ * to a @e method.
+ *
+ * @param cls Closure.
+ * @param nym The sender of the message. NULL for the ego's own messages to the home.
+ * @param full_method_name Original method name from PSYC (may be more
+ * specific than the registered method name due to try-and-slice matching).
+
+ * @param message_id Unique message counter for this message
+ * (unique only in combination with the given sender for
+ * this channel).
+ * @param modifier_count Number of elements in the @a modifiers array.
+ * @param modifiers Modifiers present in the message. FIXME: use environment instead?
+ * @param data_offset Byte offset of @a data in the overall data of the method.
+ * @param data Data stream given to the method (might not be zero-terminated
+ * if data is binary).
+ * @param data_size Number of bytes in @a data.
+ * @param flags Message flags indicating fragmentation status.
+ */
+typedef int
+(*GNUNET_SOCIAL_Method) (void *cls,
+ struct GNUNET_SOCIAL_Nym *nym,
+ const char *full_method_name,
+ uint64_t message_id,
+ size_t modifier_count,
+ GNUNET_PSYC_Modifier *modifiers,
+ uint64_t data_offset,
+ const void *data,
+ size_t data_size,
+ enum GNUNET_PSYC_MessageFlags flags);
+
+
+/**
+ * Create a try-and-slice instance.
+ *
+ * @return A new try-and-slice construct.
+ */
+struct GNUNET_SOCIAL_Slicer *
+GNUNET_SOCIAL_slicer_create (void);
+
+
+/**
+ * Add a method to the try-and-slice instance.
+ *
+ * A slicer processes messages and calls methods that match a message. A match
+ * happens whenever the method name of a message starts with the method_name
+ * parameter given here.
+ *
+ * @param slicer The try-and-slice instance to extend.
+ * @param method_name Name of the given method, use empty string for default.
+ * @param method Method to invoke.
+ * @param method_cls Closure for method.
+ */
+void
+GNUNET_SOCIAL_slicer_add (struct GNUNET_SOCIAL_Slicer *slicer,
+ const char *method_name,
+ GNUNET_SOCIAL_Method method,
+ void *method_cls);
+
+
+/**
+ * Remove a registered method from the try-and-slice instance.
+ *
+ * @param slicer The try-and-slice instance.
+ * @param method_name Name of the method to remove.
+ * @param method Method handler.
+ */
+void
+GNUNET_SOCIAL_slicer_remove (struct GNUNET_SOCIAL_Slicer *slicer,
+ const char *method_name,
+ GNUNET_SOCIAL_Method method);
+
+/**
+ * Destroy a given try-and-slice instance.
+ *
+ * @param slicer slicer to destroy
+ */
+void
+GNUNET_SOCIAL_slicer_destroy (struct GNUNET_SOCIAL_Slicer *slicer);
+
+
+/**
+ * Function called asking for nym to be admitted to the place.
+ *
+ * Should call either GNUNET_SOCIAL_home_admit() or
+ * GNUNET_SOCIAL_home_reject_entry() (possibly asynchronously). If this owner
+ * cannot decide, it is fine to call neither function, in which case hopefully
+ * some other owner of the home exists that will make the decision. The @a nym
+ * reference remains valid until the #GNUNET_SOCIAL_FarewellCallback is invoked
+ * for it.
+ *
+ * @param cls Closure.
+ * @param nym Handle for the user who wants to enter.
+ * @param method_name Method name in the entry request.
+ * @param variable_count Number of elements in the @a variables array.
+ * @param variables Variables present in the message.
+ * @param data Payload given on enter (e.g. a password).
+ * @param data_size Number of bytes in @a data.
+ */
+typedef void
+(*GNUNET_SOCIAL_AnswerDoorCallback) (void *cls,
+ struct GNUNET_SOCIAL_Nym *nym,
+ size_t variable_count,
+ const char *method_name,
+ GNUNET_PSYC_Modifier *variables,
+ const void *data,
+ size_t data_size);
+
+
+/**
+ * Function called when a @a nym leaves the place.
+ *
+ * This is also called if the @a nym was never given permission to enter
+ * (i.e. the @a nym stopped asking to get in).
+ *
+ * @param cls Closure.
+ * @param nym Handle for the user who left.
+ * @param variable_count Number of elements in the @a variables array.
+ * @param variables Variables present in the message.
+ */
+typedef void
+(*GNUNET_SOCIAL_FarewellCallback) (void *cls,
+ struct GNUNET_SOCIAL_Nym *nym,
+ size_t variable_count,
+ GNUNET_PSYC_Modifier *variables);
+
+
+/**
+ * Enter a home where guests (nyms) can be hosted.
+ *
+ * A home is created upon first entering, and exists until
+ * GNUNET_SOCIAL_home_destroy() is called. It can also be left temporarily using
+ * GNUNET_SOCIAL_home_leave().
+ *
+ * @param cfg Configuration to contact the social service.
+ * @param home_keyfile File with the private-public key pair of the home,
+ * created if the file does not exist; pass NULL for ephemeral homes.
+ * @param policy Policy specifying entry and history restrictions of the home.
+ * @param ego Owner of the home (host).
+ * @param slicer Slicer to handle guests talking.
+ * @param listener_cb Function to handle new nyms that want to enter.
+ * @param farewell_cb Function to handle departing nyms.
+ * @param cls Closure for @a listener_cb and @a farewell_cb.
+ * @return Handle for a new home.
+ */
+struct GNUNET_SOCIAL_Home *
+GNUNET_SOCIAL_home_enter (const struct GNUNET_CONFIGURATION_Handle *cfg,
+ const char *home_keyfile,
+ enum GNUNET_PSYC_Policy policy,
+ struct GNUNET_IDENTITY_Ego *ego,
+ struct GNUNET_SOCIAL_Slicer *slicer,
+ GNUNET_SOCIAL_AnswerDoorCallback listener_cb,
+ GNUNET_SOCIAL_FarewellCallback farewell_cb,
+ void *cls);
+
+
+/**
+ * Admit @a nym to the @a home.
+ *
+ * The @a nym reference will remain valid until either the home is destroyed or
+ * @a nym leaves.
+ *
+ * @param home Home to allow @a nym to enter.
+ * @param nym Handle for the entity that wants to enter.
+ */
+void
+GNUNET_SOCIAL_home_admit (struct GNUNET_SOCIAL_Home *home,
+ struct GNUNET_SOCIAL_Nym *nym);
+
+
+/**
+ * Throw @a nym out of the @a home.
+ *
+ * The @a nym reference will remain valid until the
+ * #GNUNET_SOCIAL_FarewellCallback is invoked,
+ * which should be very soon after this call.
+ *
+ * @param home Home to eject @a nym from.
+ * @param nym Handle for the entity to be ejected.
+ */
+void
+GNUNET_SOCIAL_home_eject (struct GNUNET_SOCIAL_Home *home,
+ struct GNUNET_SOCIAL_Nym *nym);
+
+
+/**
+ * Refuse @a nym entry into the @a home.
+ *
+ * @param home Home to disallow @a nym to enter.
+ * @param nym Handle for the entity that wanted to enter.
+ * @param method_name Method name for the rejection message.
+ * @param env Environment containing variables for the message, or NULL.
+ * @param data Data for the rejection message to send back.
+ * @param data_size Number of bytes in @a data for method.
+ */
+void
+GNUNET_SOCIAL_home_reject_entry (struct GNUNET_SOCIAL_Home *home,
+ struct GNUNET_SOCIAL_Nym *nym,
+ const char *method_name,
+ const struct GNUNET_ENV_Environment *env,
+ const void *data,
+ size_t data_size);
+
+
+/**
+ * Get the public key of a nym.
+ *
+ * Suitable, for example, to be used with GNUNET_NAMESTORE_zone_to_name().
+ *
+ * @param nym Pseudonym to map to a cryptographic identifier.
+ * @param[out] nym_key Set to the public key of the nym.
+ */
+void
+GNUNET_SOCIAL_nym_get_key (struct GNUNET_SOCIAL_Nym *nym,
+ struct GNUNET_CRYPTO_EccPublicSignKey *nym_key);
+
+
+/**
+ * Obtain the private-public key pair of the home.
+ *
+ * @param home Home to get the key of.
+ * @param[out] home_key Set to the private-public key pair of the home. The public part is suitable for storing in GNS within a "PLACE" record, along with peer IDs to join at.
+ */
+void
+GNUNET_SOCIAL_home_get_key (struct GNUNET_SOCIAL_Home *home,
+ struct GNUNET_CRYPTO_EccPrivateKey *home_key);
+
+
+/**
+ * Advertise @a home under @a name in the GNS zone of the @e ego.
+ *
+ * @param home The home to advertise.
+ * @param name The name for the PLACE record to put in the zone.
+ * @param peer_count Number of elements in the @a peers array.
+ * @param peers List of peers in the PLACE record that can be used to send join
+ * requests to.
+ * @param expiration_time Expiration time of the record, use 0 to remove the record.
+ * @param password Password used to encrypt the record.
+ */
+void
+GNUNET_SOCIAL_home_advertise (struct GNUNET_SOCIAL_Home *home,
+ const char *name,
+ size_t peer_count,
+ const struct GNUNET_PeerIdentity *peers,
+ GNUNET_TIME_Relative expiration_time,
+ const char *password);
+
+
+/**
+ * Flags for announcements in a home.
+ */
+enum GNUNET_PSYC_AnnouncementFlags
+{
+ /**
+ * Whether this announcement removes all objects from the home.
+ *
+ * New objects can be still added to the now empty home using the @e env
+ * parameter of the same announcement.
+ */
+ GNUNET_SOCIAL_ANNOUNCEMENT_CLEAR_OBJECTS = 1 << 0
+};
+
+
+/**
+ * Handle for an announcement request.
+ */
+struct GNUNET_SOCIAL_Announcement;
+
+
+/**
+ * Send a message to all nyms that are present in the home.
+ *
+ * This function is restricted to the home owner. Nyms can only send requests
+ * to the home owner who can decide to relay it to other guests.
+ *
+ * @param home Home to address the announcement to.
+ * @param method_name Method to use for the announcement.
+ * @param env Environment containing variables for the message and operations on
+ * objects of the home, or NULL.
+ * @param notify Function to call to get the payload of the announcement.
+ * @param notify_cls Closure for @a notify.
+ * @param flags Flags for this announcement.
+ * @return NULL on error (announcement already in progress?).
+ */
+struct GNUNET_SOCIAL_Announcement *
+GNUNET_SOCIAL_home_announce (struct GNUNET_SOCIAL_Home *home,
+ const char *method_name,
+ const struct GNUNET_ENV_Environment *env,
+ GNUNET_CONNECTION_TransmitReadyNotify notify,
+ void *notify_cls,
+ GNUNET_SOCIAL_AnnouncementFlags flags);
+
+
+/**
+ * Cancel announcement.
+ *
+ * @param a The announcement to cancel.
+ */
+void
+GNUNET_SOCIAL_home_announce_cancel (struct GNUNET_SOCIAL_Announcement *a);
+
+
+/**
+ * Convert our home to a place so we can access it via the place API.
+ *
+ * @param home Handle for the home.
+ * @param keep_active Keep home active after last application disconnected.
+ * @return Place handle for the same home, valid as long as @a home is valid;
+ * do NOT try to GNUNET_SOCIAL_place_leave() this place, it's your home!
+ */
+struct GNUNET_SOCIAL_Place *
+GNUNET_SOCIAL_home_get_place (struct GNUNET_SOCIAL_Home *home, int keep_active);
+
+
+/**
+ * Leave a home.
+
+ * Invalidates home handle.
+ * Guests will be disconnected until the home is restarted.
+ *
+ * @param home Home to leave.
+ */
+void
+GNUNET_SOCIAL_home_leave (struct GNUNET_SOCIAL_Home *home);
+
+/**
+ * Request entry to a place (home hosted by someone else).
+ *
+ * @param cfg Configuration to contact the social service.
+ * @param ego Owner of the home (host).
+ * @param address GNS name of the place to enter. Either in the form of
+ * 'room.friend.gnu', or 'NYMPUBKEY.zkey'. This latter case refers to
+ * the 'PLACE' record of the empty label ("+") in the GNS zone with the
+ * nym's public key 'NYMPUBKEY', and can be used to request entry to a
+ * pseudonym's place directly.
+ * @param method_name Method name for the message.
+ * @param env Environment containing variables for the message, or NULL.
+ * @param data Payload for the message to give to the enter callback.
+ * @param data_size Number of bytes in @a data.
+ * @param slicer Slicer to use for processing incoming requests from guests.
+ * @return NULL on errors, otherwise handle to the place.
+ */
+struct GNUNET_SOCIAL_Place *
+GNUNET_SOCIAL_place_enter (const struct GNUNET_CONFIGURATION_Handle *cfg,
+ struct GNUNET_IDENTITY_Ego *ego,
+ char *address,
+ const char *method_name,
+ const struct GNUNET_ENV_Environment *env,
+ const void *data,
+ size_t data_size,
+ struct GNUNET_SOCIAL_Slicer *slicer);
+
+/**
+ * Request entry to a place (home hosted by someone else).
+ *
+ * @param cfg Configuration to contact the social service.
+ * @param ego Owner of the home (host).
+ * @param crypto_address Public key of the place to enter.
+ * @param origin Peer identity of the origin of the underlying multicast group.
+ * @param relay_count Number of elements in the @a relays array.
+ * @param relays Relays for the underlying multicast group.
+ * @param method_name Method name for the message.
+ * @param env Environment containing variables for the message, or NULL.
+ * @param data Payload for the message to give to the enter callback.
+ * @param data_size Number of bytes in @a data.
+ * @param slicer Slicer to use for processing incoming requests from guests.
+ * @return NULL on errors, otherwise handle to the place.
+ */
+struct GNUNET_SOCIAL_Place *
+GNUNET_SOCIAL_place_enter2 (const struct GNUNET_CONFIGURATION_Handle *cfg,
+ struct GNUNET_IDENTITY_Ego *ego,
+ struct GNUNET_CRYPTO_EccPublicSignKey *crypto_address,
+ struct GNUNET_PeerIdentity *origin,
+ size_t relay_count,
+ struct GNUNET_PeerIdentity *relays,
+ const char *method_name,
+ const struct GNUNET_ENV_Environment *env,
+ const void *data,
+ size_t data_size,
+ struct GNUNET_SOCIAL_Slicer *slicer);
+
+
+struct GNUNET_SOCIAL_WatchHandle;
+
/**
- * Handle for a social channel
+ * Watch a place for changed objects.
+ *
+ * @param place Place to watch.
+ * @param object_filter Object prefix to match.
+ * @param state_cb Function to call when an object/state changes.
+ * @param state_cb_cls Closure for callback.
+ *
+ * @return Handle that can be used to cancel watching.
*/
-struct GNUNET_SOCIAL_Channel;
+struct GNUNET_SOCIAL_WatchHandle *
+GNUNET_SOCIAL_place_watch (struct GNUNET_SOCIAL_Place *place,
+ const char *object_filter,
+ GNUNET_PSYC_StateCallback state_cb,
+ void *state_cb_cls);
+
+
+/**
+ * Cancel watching a place for changed objects.
+ *
+ * @param wh Watch handle to cancel.
+ */
+void
+GNUNET_SOCIAL_place_watch_cancel (struct GNUNET_SOCIAL_WatchHandle *wh);
+
+
+struct GNUNET_SOCIAL_LookHandle;
+
+
+/**
+ * Look at objects in the place with a matching name prefix.
+ *
+ * @param place The place to look its objects at.
+ * @param name_prefix Look at objects with names beginning with this value.
+ * @param state_cb Function to call for each object found.
+ * @param state_cb_cls Closure for callback function.
+ *
+ * @return Handle that can be used to stop looking at objects.
+ */
+struct GNUNET_SOCIAL_LookHandle *
+GNUNET_SOCIAL_place_look (struct GNUNET_SOCIAL_Place *place,
+ const char *name_prefix,
+ GNUNET_PSYC_StateCallback state_cb,
+ void *state_cb_cls);
+
+
+/**
+ * Stop looking at objects.
+ *
+ * @param lh Look handle to stop.
+ */
+void
+GNUNET_SOCIAL_place_look_cancel (struct GNUNET_SOCIAL_LookHandle *lh);
+
+
+
+/**
+ * Look at a particular object in the place.
+ *
+ * The best matching object is returned (its name might be less specific than
+ * what was requested).
+ *
+ * @param place The place to look the object at.
+ * @param full_name Full name of the object.
+ * @param value_size Set to the size of the returned value.
+ * @return NULL if there is no such object at this place.
+ */
+const void *
+GNUNET_SOCIAL_place_look_at (struct GNUNET_SOCIAL_Place *place,
+ const char *full_name,
+ size_t *value_size);
+
+
+/**
+ * Flags for talking to the host of a place.
+ */
+enum GNUNET_SOCIAL_TalkFlags;
+
+
+/**
+ * A talk request.
+ */
+struct GNUNET_SOCIAL_TalkRequest;
+
+/**
+ * Talk to the host of the place.
+ *
+ * @param place Place where we want to talk to the host.
+ * @param method_name Method to invoke on the host.
+ * @param env Environment containing variables for the message, or NULL.
+ * @param notify Function to use to get the payload for the method.
+ * @param notify_cls Closure for @a notify.
+ * @param flags Flags for the message being sent.
+ * @return NULL if we are already trying to talk to the host,
+ * otherwise handle to cancel the request.
+ */
+struct GNUNET_SOCIAL_TalkRequest *
+GNUNET_SOCIAL_place_talk (struct GNUNET_SOCIAL_Place *place,
+ const char *method_name,
+ const struct GNUNET_ENV_Environment *env,
+ GNUNET_CONNECTION_TransmitReadyNotify notify,
+ void *notify_cls,
+ GNUNET_SOCIAL_TalkFlags flags);
+
+
+/**
+ * Cancel talking to the host of the place.
+ *
+ * @param tr Talk request to cancel.
+ */
+void
+GNUNET_SOCIAL_place_talk_cancel (struct GNUNET_SOCIAL_TalkRequest *tr);
+
+
+/**
+ * A history lesson.
+ */
+struct GNUNET_SOCIAL_HistoryLesson;
+
+/**
+ * Learn about the history of a place.
+ *
+ * Sends messages through the slicer function of the place where
+ * start_message_id <= message_id <= end_message_id.
+ * The messages will have the #GNUNET_PSYC_MESSAGE_HISTORIC flag set.
+ *
+ * To get the latest message, use 0 for both the start and end message ID.
+ *
+ * @param place Place we want to learn more about.
+ * @param start_message_id First historic message we are interested in.
+ * @param end_message_id Last historic message we are interested in (inclusive).
+ * @param slicer Slicer to use to process history. Can be the same as the
+ * slicer of the place, as the HISTORIC flag allows distinguishing
+ * old messages from fresh ones.
+ * @param finish_cb Function called after the last message if the history lesson
+ * is passed through the @a slicer. NULL if not needed.
+ * @param finish_cb_cls Closure for @a finish_cb.
+ * @return Handle to abort history lesson, never NULL (multiple lessons
+ * at the same time are allowed).
+ */
+struct GNUNET_SOCIAL_HistoryLesson *
+GNUNET_SOCIAL_place_get_history (struct GNUNET_SOCIAL_Place *place,
+ uint64_t start_message_id,
+ uint64_t end_message_id,
+ const struct GNUNET_SOCIAL_Slicer *slicer,
+ void (*finish_cb)(void *),
+ void *finish_cb_cls);
+
+
+/**
+ * Stop processing messages from the history lesson.
+ *
+ * Must not be called after the finish callback of the history lesson is called.
+ *
+ * @param hist History lesson to cancel.
+ */
+void
+GNUNET_SOCIAL_place_get_history_cancel (struct GNUNET_SOCIAL_HistoryLesson *hist);
+
/**
- * Handle for a social client
+ * Leave a place permanently.
+ *
+ * Notifies the owner of the place about leaving, and destroys the place handle.
+ *
+ * @param place Place to leave permanently.
+ * @param keep_active Keep place active after last application disconnected.
*/
-struct GNUNET_SOCIAL_Client;
+void
+GNUNET_SOCIAL_place_leave (struct GNUNET_SOCIAL_Place *place, int keep_active);
#if 0 /* keep Emacsens' auto-indent happy */