X-Git-Url: https://git.librecmc.org/?a=blobdiff_plain;f=src%2Finclude%2Fgnunet_multicast_service.h;h=541bdd90deb4aed3e3a9aaef11253577bfb94f0e;hb=418bf5953acdba2e325528d739fb115b51b7141f;hp=9573f3e087f78d2a20280637bb19fbaf9128fc45;hpb=8ee4ad79af4d0db83c5fd60027bb5f8f11e27ef3;p=oweals%2Fgnunet.git diff --git a/src/include/gnunet_multicast_service.h b/src/include/gnunet_multicast_service.h index 9573f3e08..541bdd90d 100644 --- a/src/include/gnunet_multicast_service.h +++ b/src/include/gnunet_multicast_service.h @@ -1,27 +1,31 @@ /* This file is part of GNUnet. - (C) 2012, 2013 Christian Grothoff (and other contributing authors) + Copyright (C) 2012, 2013 GNUnet e.V. - GNUnet 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 3, or (at your - option) any later version. + GNUnet is free software: you can redistribute it and/or modify it + under the terms of the GNU Affero General Public License as published + by the Free Software Foundation, either version 3 of the License, + or (at your option) any later version. GNUnet is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU - General Public License for more details. - - You should have received a copy of the GNU General Public License - along with GNUnet; see the file COPYING. If not, write to the - Free Software Foundation, Inc., 59 Temple Place - Suite 330, - Boston, MA 02111-1307, USA. + Affero General Public License for more details. + + You should have received a copy of the GNU Affero General Public License + along with this program. If not, see . */ /** - * @file include/gnunet_multicast_service.h - * @brief multicast service; establish tunnels to distant peers + * @author Gabor X Toth * @author Christian Grothoff + * + * @file + * Multicast service; multicast messaging via CADET + * + * @defgroup multicast Multicast service + * Multicast messaging via CADET. + * @{ */ #ifndef GNUNET_MULTICAST_SERVICE_H @@ -43,7 +47,6 @@ extern "C" */ #define GNUNET_MULTICAST_VERSION 0x00000000 - /** * Opaque handle for a multicast group member. */ @@ -54,513 +57,858 @@ struct GNUNET_MULTICAST_Member; */ struct GNUNET_MULTICAST_Origin; -/** - * Group membership policies. - */ -enum GNUNET_MULTICAST_JoinPolicy + +enum GNUNET_MULTICAST_MessageFlags { /** - * Anyone can join the group, without announcing his presence; all - * messages are always public and can be distributed freely. Joins - * may be announced, but this is not required. + * First fragment of a message. */ - GNUNET_MULTICAST_JP_ANONYMOUS = 0, + GNUNET_MULTICAST_MESSAGE_FIRST_FRAGMENT = 1 << 0, /** - * Origin must approve membership to the group, messages must only be - * distributed to current group members. This includes the group - * state as well as transient messages. + * Last fragment of a message. */ - GNUNET_MULTICAST_JP_PRIVATE = 1 + GNUNET_MULTICAST_MESSAGE_LAST_FRAGMENT = 1 << 1, -#if IDEAS_FOR_FUTURE /** - * Anyone can freely join the group (no approval required); however, - * transient messages must only be distributed to current group - * members, so the origin must still acknowledge that the member - * joined before transient messages are delivered. As approval is - * guaranteed, the presistent group state can de synchronized freely - * immediately, prior to origin confirmation + * OR'ed flags if message is not fragmented. */ - GNUNET_MULTICAST_JP_OPEN = 2 -#endif + GNUNET_MULTICAST_MESSAGE_NOT_FRAGMENTED + = GNUNET_MULTICAST_MESSAGE_FIRST_FRAGMENT + | GNUNET_MULTICAST_MESSAGE_LAST_FRAGMENT, + + /** + * Historic message, used only locally when replaying messages from local + * storage. + */ + GNUNET_MULTICAST_MESSAGE_HISTORIC = 1 << 30 }; -/** - * Opaque handle to a replay request from the multicast service. - */ -struct GNUNET_MULTICAST_ReplayHandle; - +GNUNET_NETWORK_STRUCT_BEGIN /** - * Functions with this signature are called whenever the multicast - * service needs a message to be replayed. Implementations of this - * function MUST call 'GNUNET_MULTICAST_replay' ONCE (with a message - * or an error); however, if the origin is destroyed or the group is - * left, the replay handle must no longer be used. + * Header of a multicast message fragment. * - * @param cls closure (set from GNUNET_MULTICAST_origin_start/join) - * @param message_id which message should be replayed - * @param rh handle to pass to message transmit function + * This format is public as the replay mechanism must replay message fragments using the + * same format. This is needed as we want to integrity-check message fragments within + * the multicast layer to avoid multicasting mal-formed messages. */ -typedef void (*GNUNET_MULTICAST_ReplayCallback) (void *cls, - uint64_t message_id, - struct GNUNET_MULTICAST_ReplayHandle *rh); +struct GNUNET_MULTICAST_MessageHeader +{ + /** + * Header for all multicast message fragments from the origin. + */ + struct GNUNET_MessageHeader header; -/** - * Possible error codes during replay. - */ -enum GNUNET_MULTICAST_ReplayErrorCode -{ - /** - * Everything is fine. - */ - GNUNET_MULTICAST_REC_OK = 0, + * Number of hops this message fragment has taken since the origin. + * + * Helpful to determine shortest paths to the origin among honest peers for + * unicast requests from members. Updated at each hop and thus not signed and + * not secure. + */ + uint32_t hop_counter GNUNET_PACKED; /** - * Message has been discarded (likely transient message that was too old). - */ - GNUNET_MULTICAST_REC_TRANSIENT_LOST = 1, + * ECC signature of the message fragment. + * + * Signature must match the public key of the multicast group. + */ + struct GNUNET_CRYPTO_EddsaSignature signature; /** - * Message ID counter was larger than the highest counter this - * replay function has ever encountered; thus it is likely the - * origin never sent it and we're at the HEAD of the multicast - * stream as far as this node is concerned. - */ - GNUNET_MULTICAST_REC_PAST_HEAD = 2, + * Purpose for the signature and size of the signed data. + */ + struct GNUNET_CRYPTO_EccSignaturePurpose purpose; /** - * Internal error (i.e. database error). Try some other peer. - */ - GNUNET_MULTICAST_REC_INTERNAL_ERROR = 3 + * Number of the message fragment, monotonically increasing starting from 1. + */ + uint64_t fragment_id GNUNET_PACKED; -}; + /** + * Byte offset of this @e fragment of the @e message. + */ + uint64_t fragment_offset GNUNET_PACKED; + /** + * Number of the message this fragment belongs to. + * + * Set in GNUNET_MULTICAST_origin_to_all(). + */ + uint64_t message_id GNUNET_PACKED; + + /** + * Counter that monotonically increases whenever a member parts the group. + * + * Set in GNUNET_MULTICAST_origin_to_all(). + * + * It has significance in case of replay requests: when a member has missed + * messages and gets a replay request: in this case if the @a group_generation + * is still the same before and after the missed messages, it means that no + * @e join or @e part operations happened during the missed messages. + */ + uint64_t group_generation GNUNET_PACKED; + + /** + * Flags for this message fragment. + * + * @see enum GNUNET_MULTICAST_MessageFlags + */ + uint32_t flags GNUNET_PACKED; + + /* Followed by message body. */ +}; -GNUNET_NETWORK_STRUCT_BEGIN /** - * Header of a multicast message. This format is public as the replay - * mechanism must replay messages using the same format. This is - * needed as we want to integrity-check messages within the multicast - * layer to avoid multicasting mal-formed messages. + * Header of a request from a member to the origin. */ -struct GNUNET_MULTICAST_MessageHeader +struct GNUNET_MULTICAST_RequestHeader { - /** - * Header for all multicast messages from the origin. + * Header for all requests from a member to the origin. */ struct GNUNET_MessageHeader header; /** - * How many hops has this message taken since the origin? - * (helpful to determine shortest paths to the origin for responses - * among honest peers; updated at each hop and thus not signed - * and not secure) + * Public key of the sending member. */ - uint32_t hop_counter GNUNET_PACKED; + struct GNUNET_CRYPTO_EcdsaPublicKey member_pub_key; /** - * ECC signature of the message. Signature must match the public - * key of the multicast group. + * ECC signature of the request fragment. + * + * Signature must match the public key of the multicast group. */ - struct GNUNET_CRYPTO_EccSignature signature; + struct GNUNET_CRYPTO_EcdsaSignature signature; /** - * Signature of the multicast message. + * Purpose for the signature and size of the signed data. */ struct GNUNET_CRYPTO_EccSignaturePurpose purpose; /** - * Number of the message, monotonically increasing. + * Number of the request fragment. + * Monotonically increasing from 1. */ - uint64_t message_id GNUNET_PACKED; + uint64_t fragment_id GNUNET_PACKED; /** - * Counter that monotonically increases whenever a member - * leaves the group. + * Byte offset of this @e fragment of the @e request. */ - uint64_t group_generation GNUNET_PACKED; + uint64_t fragment_offset GNUNET_PACKED; /** - * Difference between the current message_id and the message_id of - * the preceeding non-transient message. Zero for transient - * messages, UINT64_MAX for the first message, or any other message - * creating a full state reset by the origin. By subtracting - * 'state_delta' from 'message_id', it is possible to calculate the - * message ID of the preceeding non-transient message and thus - * quickly traverse all state changes up to the last full state - * reset by the origin. This is useful as it allows joining clients - * to quickly reassemble the state while skipping over transient - * messages (and doing so without having to trust intermediaries to - * do it right, as the indices in the chain are signed). If the - * state chain is getting too long, the origin can choose to - * originate a state message with a state_delta of UINT64_MAX, - * thereby starting a new chain. The origin will then have to - * re-create the full state with state update messages following the - * state reset message. + * Number of the request this fragment belongs to. * - * Open question: needed in multicast, or just have this in PSYC; - * still might be useful for selective fetching of messages. - * Still, that again should that not be done by PSYC? + * Set in GNUNET_MULTICAST_origin_to_all(). */ - uint64_t state_delta GNUNET_PACKED; + uint64_t request_id GNUNET_PACKED; /** - * Header for the message body. Three message types are - * specifically understood by multicast, namely "peer join", "peer - * leave", and "group terminated". Multicast will use those - * messages to update its list of candidates for content - * distribution. All other message types are application-specific. + * Flags for this request. */ - struct GNUNET_MessageHeader body; + enum GNUNET_MULTICAST_MessageFlags flags GNUNET_PACKED; - /* followed by message body */ + /* Followed by request body. */ }; GNUNET_NETWORK_STRUCT_END /** - * Replay a message from the multicast group. - * - * @param rh replay handle identifying which replay operation was requested - * @param msg replayed message, NULL if unknown/error - * @param ec error code + * Maximum size of a multicast message fragment. */ -void -GNUNET_MULTICAST_replay (struct GNUNET_MULTICAST_ReplayHandle *rh, - const struct GNUNET_MULTICAST_MessageHeader *msg, - enum GNUNET_MULTICAST_ReplayErrorCode ec); +#define GNUNET_MULTICAST_FRAGMENT_MAX_SIZE (63 * 1024) + +#define GNUNET_MULTICAST_FRAGMENT_MAX_PAYLOAD \ + (GNUNET_MULTICAST_FRAGMENT_MAX_SIZE \ + - sizeof (struct GNUNET_MULTICAST_MessageHeader)) /** - * Handle that identifies a join request (to match calls to the - * 'GNUNET_MULTICAST_MembershipChangeCallback' to the corresponding - * calls to 'GNUNET_MULTICAST_join_decision'). + * Handle that identifies a join request. + * + * Used to match calls to #GNUNET_MULTICAST_JoinRequestCallback to the + * corresponding calls to #GNUNET_MULTICAST_join_decision(). */ -struct GNUNET_MULTICAST_JoinHande; +struct GNUNET_MULTICAST_JoinHandle; /** - * Function to call with the decision made for a membership change - * request. Must be called once and only once in response to an - * invocation of the 'GNUNET_MULTICAST_MembershipChangeCallback'. + * Function to call with the decision made for a join request. * - * @param jh join request handle - * @param join_response message to send in response to the joining peer; - * can also be used to redirect the peer to a different group at the - * application layer; this response is to be transmitted to the - * peer that issued the request even if admission is denied. - * @param is_admitted GNUNET_OK if joining is approved, GNUNET_SYSERR if it is disapproved; - * GNUNET_NO for peers leaving - * @param relay_count number of relays given - * @param relays array of suggested peers that might be useful relays to use + * Must be called once and only once in response to an invocation of the + * #GNUNET_MULTICAST_JoinRequestCallback. + * + * @param jh + * Join request handle. + * @param is_admitted + * #GNUNET_YES if the join is approved, + * #GNUNET_NO if it is disapproved, + * #GNUNET_SYSERR if we cannot answer the request. + * @param relay_count + * Number of relays given. + * @param relays + * Array of suggested peers that might be useful relays to use * when joining the multicast group (essentially a list of peers that * are already part of the multicast group and might thus be willing * to help with routing). If empty, only this local peer (which must * be the multicast origin) is a good candidate for building the * multicast tree. Note that it is unnecessary to specify our own * peer identity in this array. + * @param join_resp + * Message to send in response to the joining peer; + * can also be used to redirect the peer to a different group at the + * application layer; this response is to be transmitted to the + * peer that issued the request even if admission is denied. */ -void +struct GNUNET_MULTICAST_ReplayHandle * GNUNET_MULTICAST_join_decision (struct GNUNET_MULTICAST_JoinHandle *jh, - const struct GNUNET_MessageHeader *join_response, - int is_admitted, - unsigned int relay_count, - const struct GNUNET_PeerIdentity *relays); + int is_admitted, + uint16_t relay_count, + const struct GNUNET_PeerIdentity *relays, + const struct GNUNET_MessageHeader *join_resp); /** - * Method called whenever another peer wants to join or has left a - * multicast group. Implementations of this function must call - * 'GNUNET_MULTICAST_join_decision' with the decision. + * Method called whenever another peer wants to join the multicast group. + * + * Implementations of this function must call GNUNET_MULTICAST_join_decision() + * with the decision. * - * @param cls closure - * @param peer identity of the peer that wants to join or leave - * @param join_req application-dependent join message from the new user - * (might, for example, contain a user - * bind user identity/pseudonym to peer identity, application-level - * message to origin, etc.) - * @param is_joining GNUNET_YES if the peer wants to join, GNUNET_NO if the peer left - * @param jh join handle to pass to 'GNUNET_MULTICAST_join_decison' + * @param cls + * Closure. + * @param member_pub_key + * Public key of the member requesting join. + * @param join_msg + * Application-dependent join message from the new member. + * @param jh + * Join handle to pass to GNUNET_MULTICAST_join_decison(). */ -typedef void (*GNUNET_MULTICAST_MembershipChangeCallback)(void *cls, - const struct GNUNET_PeerIdentity *peer, - const struct GNUNET_MessageHeader *join_req, - int is_joining, - struct GNUNET_MULTICAST_JoinHandle *jh); +typedef void +(*GNUNET_MULTICAST_JoinRequestCallback) (void *cls, + const struct GNUNET_CRYPTO_EcdsaPublicKey *member_pub_key, + const struct GNUNET_MessageHeader *join_msg, + struct GNUNET_MULTICAST_JoinHandle *jh); /** - * Handle to pass back for the answer of a membership test. + * Method called to inform about the decision in response to a join request. + * + * If @a is_admitted is not #GNUNET_YES, then the multicast service disconnects + * the client and the multicast member handle returned by + * GNUNET_MULTICAST_member_join() is invalidated. + * + * @param cls + * Closure. + * @param is_admitted + * #GNUNET_YES or #GNUNET_NO or #GNUNET_SYSERR + * @param peer + * The peer we are connected to and the join decision is from. + * @param relay_count + * Number of peers in the @a relays array. + * @param relays + * Peer identities of members of the group, which serve as relays + * and can be used to join the group at. If empty, only the origin can + * be used to connect to the group. + * @param join_msg + * Application-dependent join message from the origin. + */ +typedef void +(*GNUNET_MULTICAST_JoinDecisionCallback) (void *cls, + int is_admitted, + const struct GNUNET_PeerIdentity *peer, + uint16_t relay_count, + const struct GNUNET_PeerIdentity *relays, + const struct GNUNET_MessageHeader *join_msg); + + +/** + * Function called whenever a group member has transmitted a request + * to the origin (other than joining or leaving). + * + * FIXME: need to distinguish between origin cancelling a message (some fragments + * were sent, then the rest 'discarded') and the case where we got disconnected; + * right now, both would mean 'msg' is NULL, but they could be quite different... + * So the semantics from the receiver side of + * GNUNET_MULTICAST_member_to_origin_cancel() are not clear here. Maybe we + * should do something with the flags in this case? + * + * @param cls + * Closure (set from GNUNET_MULTICAST_origin_start). + * @param sender + * Identity of the sender. + * @param req + * Request to the origin. + * @param flags + * Flags for the request. + */ +typedef void +(*GNUNET_MULTICAST_RequestCallback) (void *cls, + const struct GNUNET_MULTICAST_RequestHeader *req); + + +/** + * Function called whenever a group member is receiving a message fragment from + * the origin. + * + * If admission to the group is denied, this function is called once with the + * response of the @e origin (as given to GNUNET_MULTICAST_join_decision()) and + * then a second time with NULL to indicate that the connection failed for good. + * + * FIXME: need to distinguish between origin cancelling a message (some fragments + * were sent, then the rest 'discarded') and the case where we got disconnected; + * right now, both would mean 'msg' is NULL, but they could be quite different... + * So the semantics from the receiver side of + * GNUNET_MULTICAST_origin_to_all_cancel() are not clear here. + * + * @param cls + * Closure (set from GNUNET_MULTICAST_member_join()) + * @param msg + * Message from the origin, NULL if the origin shut down + * (or we were kicked out, and we should thus call + * GNUNET_MULTICAST_member_part() next) */ -struct GNUNET_MULTICAST_MembershipTestHandle; +typedef void +(*GNUNET_MULTICAST_MessageCallback) (void *cls, + const struct GNUNET_MULTICAST_MessageHeader *msg); /** - * Call informing multicast about the decision taken for membership test. + * Opaque handle to a replay request from the multicast service. + */ +struct GNUNET_MULTICAST_ReplayHandle; + + +/** + * Functions with this signature are called whenever the multicast service needs + * a message fragment to be replayed by fragment_id. + * + * Implementations of this function MUST call GNUNET_MULTICAST_replay() ONCE + * (with a message or an error); however, if the origin is destroyed or the + * group is left, the replay handle must no longer be used. * - * @param mth handle that was given for the query - * @param decision GNUNET_YES if peer was a member, GNUNET_NO if peer was not a member, - * GNUNET_SYSERR if we cannot answer the membership test + * @param cls + * Closure (set from GNUNET_MULTICAST_origin_start() + * or GNUNET_MULTICAST_member_join()). + * @param member_pub_key + * The member requesting replay. + * @param fragment_id + * Which message fragment should be replayed. + * @param flags + * Flags for the replay. + * @param rh + * Handle to pass to message transmit function. + */ +typedef void +(*GNUNET_MULTICAST_ReplayFragmentCallback) (void *cls, + const struct GNUNET_CRYPTO_EcdsaPublicKey *member_pub_key, + uint64_t fragment_id, + uint64_t flags, + struct GNUNET_MULTICAST_ReplayHandle *rh); + +/** + * Functions with this signature are called whenever the multicast service needs + * a message fragment to be replayed by message_id and fragment_offset. + * + * Implementations of this function MUST call GNUNET_MULTICAST_replay() ONCE + * (with a message or an error); however, if the origin is destroyed or the + * group is left, the replay handle must no longer be used. + * + * @param cls + * Closure (set from GNUNET_MULTICAST_origin_start() + * or GNUNET_MULTICAST_member_join()). + * @param member_pub_key + * The member requesting replay. + * @param message_id + * Which message should be replayed. + * @param fragment_offset + * Offset of the fragment within of @a message_id to be replayed. + * @param flags + * Flags for the replay. + * @param rh + * Handle to pass to message transmit function. + */ +typedef void +(*GNUNET_MULTICAST_ReplayMessageCallback) (void *cls, + const struct GNUNET_CRYPTO_EcdsaPublicKey *member_pub_key, + uint64_t message_id, + uint64_t fragment_offset, + uint64_t flags, + struct GNUNET_MULTICAST_ReplayHandle *rh); + + +/** + * Possible error codes during replay. + */ +enum GNUNET_MULTICAST_ReplayErrorCode +{ + + /** + * Everything is fine. + */ + GNUNET_MULTICAST_REC_OK = 0, + + /** + * Message fragment not found in the message store. + * + * Either discarded if it is too old, or not arrived yet if this member has + * missed some messages. + */ + GNUNET_MULTICAST_REC_NOT_FOUND = 1, + + /** + * Fragment ID counter was larger than the highest counter this + * replay function has ever encountered; thus it is likely the + * origin never sent it and we're at the HEAD of the multicast + * stream as far as this node is concerned. + * + * FIXME: needed? + */ + GNUNET_MULTICAST_REC_PAST_HEAD = 2, + + /** + * Access is denied to the requested fragment, membership test did not pass. + */ + GNUNET_MULTICAST_REC_ACCESS_DENIED = 3, + + /** + * Internal error (i.e. database error). Try some other peer. + */ + GNUNET_MULTICAST_REC_INTERNAL_ERROR = 4 + +}; + + +/** + * Replay a message fragment for the multicast group. + * + * @param rh + * Replay handle identifying which replay operation was requested. + * @param msg + * Replayed message fragment, NULL if not found / an error occurred. + * @param ec + * Error code. See enum GNUNET_MULTICAST_ReplayErrorCode + * If not #GNUNET_MULTICAST_REC_OK, the replay handle is invalidated. */ void -GNUNET_MULTICAST_membership_test_answer (struct GNUNET_MULTICAST_MembershipTestHandle *mth, - int decision); +GNUNET_MULTICAST_replay_response (struct GNUNET_MULTICAST_ReplayHandle *rh, + const struct GNUNET_MessageHeader *msg, + enum GNUNET_MULTICAST_ReplayErrorCode ec); /** - * Method called to test if a member was in the group at a particular time. + * Indicate the end of the replay session. * - * @param cls closure - * @param peer identity of the peer that we want to test - * @param message_id message ID for which we want to do the test - * @param mth handle to give to 'GNUNET_MULTICAST_membership_test_answer' + * Invalidates the replay handle. + * + * @param rh Replay session to end. */ -typedef void (*GNUNET_MULTICAST_MembershipTestCallback)(void *cls, - const struct GNUNET_PeerIdentity *peer, - uint64_t message_id, - struct GNUNET_MULTICAST_MembershipTestHandle *mth); +void +GNUNET_MULTICAST_replay_response_end (struct GNUNET_MULTICAST_ReplayHandle *rh); /** - * Function called whenever a group member has transmitted a message - * to the origin (other than joining or leaving). + * Function called to provide data for a transmission for a replay. + * + * @see GNUNET_MULTICAST_replay2() + */ +typedef int +(*GNUNET_MULTICAST_ReplayTransmitNotify) (void *cls, + size_t *data_size, + void *data); + + +/** + * Replay a message for the multicast group. + * + * @param rh + * Replay handle identifying which replay operation was requested. + * @param notify + * Function to call to get the message. + * @param notify_cls + * Closure for @a notify. + */ +void +GNUNET_MULTICAST_replay_response2 (struct GNUNET_MULTICAST_ReplayHandle *rh, + GNUNET_MULTICAST_ReplayTransmitNotify notify, + void *notify_cls); + + +/** + * Start a multicast group. + * + * Peers that issue GNUNET_MULTICAST_member_join() can transmit a join request + * to either an existing group member or to the origin. If the joining is + * approved, the member is cleared for @e replay and will begin to receive + * messages transmitted to the group. If joining is disapproved, the failed + * candidate will be given a response. Members in the group can send messages + * to the origin. + * + * TODO: This function could optionally offer to advertise the origin in the + * P2P overlay network(where?) under the respective public key so that other + * peers can find an alternate PeerId to join it. Higher level protocols may + * however provide other means of solving the problem of the offline host + * (see secushare specs about that) and therefore merely need a way to provide + * a list of possible PeerIds. + * + * @param cfg + * Configuration to use. + * @param priv_key + * ECC key that will be used to sign messages for this + * multicast session; public key is used to identify the multicast group; + * @param max_fragment_id + * Maximum fragment ID already sent to the group. + * 0 for a new group. + * @param join_request_cb + * Function called to approve / disapprove joining of a peer. + * @param replay_frag_cb + * Function that can be called to replay a message fragment. + * @param replay_msg_cb + * Function that can be called to replay a message. + * @param request_cb + * Function called with message fragments from group members. + * @param message_cb + * Function called with the message fragments sent to the + * network by GNUNET_MULTICAST_origin_to_all(). These message fragments + * should be stored for answering replay requests later. + * @param cls + * Closure for the various callbacks that follow. * - * @param cls closure (set from GNUNET_MULTICAST_origin_start) - * @param sender identity of the sender - * @param response_id unique counter for the response from this sender to this origin - * @param msg message to the origin - */ -typedef void (*GNUNET_MULTICAST_ResponseCallback) (void *cls, - const struct GNUNET_PeerIdentity *sender, - uint64_t response_id, - const struct GNUNET_MessageHeader *msg); - - -/** - * Function called whenever a group member is receiving a message from - * the origin. If admission to the group is denied, this function is - * called once with the response of the 'origin' (as given to - * 'GNUNET_MULTICAST_join_decision') and then a second time with "NULL" - * to indicate that the connection failed for good. - * - * @param cls closure (set from GNUNET_MULTICAST_member_join) - * @param message_id unique number of the message, 0 for response to join request, - * normal message IDs in either direction start at 1. - * @param msg message from the origin, NULL if the origin shut down - * (or we were kicked out, and we should thus call GNUNET_MULTICAST_member_leave next) - */ -typedef void (*GNUNET_MULTICAST_MulticastMessageCallback) (void *cls, - uint64_t message_id, - const struct GNUNET_MULTICAST_MessageHeader *msg); - - -/** - * Start a multicast group. Will advertise the origin in the P2P - * overlay network under the respective public key so that other peer - * can find this peer to join it. Peers that issue - * 'GNUNET_MULTICAST_member_join' can then transmit a join request to - * either an existing group member (if the 'join_policy' is - * permissive) or to the origin. If the joining is approved, the - * member is cleared for 'replay' and will begin to receive messages - * transmitted to the group. If joining is disapproved, the failed - * candidate will be given a response. Members in the group can send - * messages to the origin (one at a time). - * - * @param cfg configuration to use - * @param cls closure for the various callbacks that follow - * @param priv_key ECC key that will be used to sign messages for this - * multicast session; public key is used to identify the - * multicast group; FIXME: we'll likely want to use - * NOT the p521 curve here, but a cheaper one in the future - * @param join_policy what is the membership policy of the group? - * @param replay_cb function that can be called to replay a message - * @param test_cb function multicast can use to test group membership - * @param join_cb function called to approve / disapprove joining of a peer - * @param response_cb function called with messages from group members - * @return handle for the origin, NULL on error + * @return Handle for the origin, NULL on error. */ struct GNUNET_MULTICAST_Origin * -GNUNET_MULTICAST_origin_start (const struct GNUNET_CONFIGURATION_Handle *cfg, - void *cls, - const struct GNUNET_CRYPTO_EccPrivateKey *priv_key, - enum GNUNET_MULTICAST_JoinPolicy join_policy, - GNUNET_MULITCAST_ReplayCallback replay_cb, - GNUNET_MULITCAST_MembershipTestCallback test_cb, - GNUNET_MULTICAST_MembershipChangeCallback join_cb, - GNUNET_MULTICAST_ResponseCallback response_cb); +GNUNET_MULTICAST_origin_start (const struct GNUNET_CONFIGURATION_Handle *cfg, + const struct GNUNET_CRYPTO_EddsaPrivateKey *priv_key, + uint64_t max_fragment_id, + GNUNET_MULTICAST_JoinRequestCallback join_request_cb, + GNUNET_MULTICAST_ReplayFragmentCallback replay_frag_cb, + GNUNET_MULTICAST_ReplayMessageCallback replay_msg_cb, + GNUNET_MULTICAST_RequestCallback request_cb, + GNUNET_MULTICAST_MessageCallback message_cb, + void *cls); + +/** + * Function called to provide data for a transmission from the origin to all + * members. + * + * Note that returning #GNUNET_OK or #GNUNET_SYSERR (but not #GNUNET_NO) + * invalidates the respective transmission handle. + * + * @param cls + * Closure. + * @param[in,out] data_size + * Initially set to the number of bytes available in + * @a data, should be set to the number of bytes written to data. + * @param[out] data + * Where to write the body of the message to give to the + * method. The function must copy at most @a data_size bytes to @a data. + * + * @return #GNUNET_SYSERR on error (fatal, aborts transmission) + * #GNUNET_NO on success, if more data is to be transmitted later. + * Should be used if @a data_size was not big enough to take all the + * data. If 0 is returned in @a data_size the transmission is paused, + * and can be resumed with GNUNET_MULTICAST_origin_to_all_resume(). + * #GNUNET_YES if this completes the transmission (all data supplied) + * @deprecated should move to MQ-style API! + */ +typedef int +(*GNUNET_MULTICAST_OriginTransmitNotify) (void *cls, + size_t *data_size, + void *data); /** * Handle for a request to send a message to all multicast group members * (from the origin). */ -struct GNUNET_MULTICAST_MulticastRequest; +struct GNUNET_MULTICAST_OriginTransmitHandle; /** * Send a message to the multicast group. * - * @param origin handle to the multicast group - * @param size number of bytes to transmit - * @param cb function to call to get the message - * @param cb_cls closure for 'cb' - * @return NULL on error (i.e. request already pending) + * @param origin + * Handle to the multicast group. + * @param message_id + * Application layer ID for the message. Opaque to multicast. + * @param group_generation + * Group generation of the message. Documented in + * struct GNUNET_MULTICAST_MessageHeader. + * @param notify + * Function to call to get the message. + * @param notify_cls + * Closure for @a notify. + * + * @return NULL on error (i.e. request already pending). + * @deprecated should move to MQ-style API! */ -struct GNUNET_MULTICAST_MulticastRequest * -GNUNET_MULTICAST_origin_send_to_all (struct GNUNET_MULTICAST_Origin *origin, - size_t size, - GNUNET_CONNECTION_TransmitReadyNotify cb, - void *cb_cls); +struct GNUNET_MULTICAST_OriginTransmitHandle * +GNUNET_MULTICAST_origin_to_all (struct GNUNET_MULTICAST_Origin *origin, + uint64_t message_id, + uint64_t group_generation, + GNUNET_MULTICAST_OriginTransmitNotify notify, + void *notify_cls); + + + +/** + * Resume message transmission to multicast group. + * + * @param th Transmission to cancel. + */ +void +GNUNET_MULTICAST_origin_to_all_resume (struct GNUNET_MULTICAST_OriginTransmitHandle *th); /** * Cancel request for message transmission to multicast group. * - * @param mr request to cancel + * @param th Transmission to cancel. */ void -GNUNET_MULTICAST_origin_send_to_all_cancel (struct GNUNET_MULTICAST_MulticastRequest *mr); +GNUNET_MULTICAST_origin_to_all_cancel (struct GNUNET_MULTICAST_OriginTransmitHandle *th); /** - * End a multicast group. + * Stop a multicast group. * - * @param origin multicast group to terminate + * @param origin Multicast group to stop. */ void -GNUNET_MULTICAST_origin_end (struct GNUNET_MULTICAST_Origin *origin); - - -/** - * Join a multicast group. The entity joining is always the local - * peer. Further information about the candidate can be provided in - * the 'join_req' message. If the join fails, the 'message_cb' is - * invoked with a (failure) response and then with 'NULL'. If the - * join succeeds, outstanding (state) messages and ongoing multicast - * messages will be given to the 'message_cb' until the member decides - * to leave the group. The 'test_cb' and 'replay_cb' functions may be - * called at anytime by the multicast service to support relaying - * messages to other members of the group. - * - * @param cfg configuration to use - * @param cls closure for callbacks - * @param pub_key ECC key that identifies the group - * @param max_known_message_id largest known message ID to the replay service; - * all messages with IDs larger than this ID will be replayed if - * possible (lower IDs will be considered known and thus only - * be replayed upon explicit request) - * @param max_known_state_message_id largest known message ID with a non-zero - * value for the 'state_delta'; state messages with - * larger IDs than this value will be replayed with high priority - * (lower IDs will be considered known and thus only - * be replayed upon explicit request) - * @param replay_cb function that can be called to replay messages - * this peer already knows from this group; NULL if this - * client is unable to support replay - * @param test_cb function multicast can use to test group membership - * @param message_cb function to be called for all messages we - * receive from the group, excluding those our replay_cb - * already has - * @param join_req application-dependent join message to be passed to origin - * (might, for example, contain a user - * bind user identity/pseudonym to peer identity, application-level - * message to origin, etc.) - * @return handle for the member, NULL on error +GNUNET_MULTICAST_origin_stop (struct GNUNET_MULTICAST_Origin *origin, + GNUNET_ContinuationCallback stop_cb, + void *stop_cls); + + +/** + * Join a multicast group. + * + * The entity joining is always the local peer. Further information about the + * candidate can be provided in @a join_msg. If the join fails, the + * @a message_cb is invoked with a (failure) response and then with NULL. If + * the join succeeds, outstanding (state) messages and ongoing multicast + * messages will be given to the @a message_cb until the member decides to part + * the group. The @a mem_test_cb and @a replay_cb functions may be called at + * anytime by the multicast service to support relaying messages to other + * members of the group. + * + * @param cfg + * Configuration to use. + * @param group_key + * ECC public key that identifies the group to join. + * @param member_pub_key + * ECC key that identifies the member + * and used to sign requests sent to the origin. + * @param origin + * Peer ID of the origin to send unicast requsets to. If NULL, + * unicast requests are sent back via multiple hops on the reverse path + * of multicast messages. + * @param relay_count + * Number of peers in the @a relays array. + * @param relays + * Peer identities of members of the group, which serve as relays + * and can be used to join the group at. and send the @a join_request to. + * If empty, the @a join_request is sent directly to the @a origin. + * @param join_msg + * Application-dependent join message to be passed to the peer @a origin. + * @param join_request_cb + * Function called to approve / disapprove joining of a peer. + * @param join_decision_cb + * Function called to inform about the join decision. + * @param replay_frag_cb + * Function that can be called to replay message fragments + * this peer already knows from this group. NULL if this + * client is unable to support replay. + * @param replay_msg_cb + * Function that can be called to replay message fragments + * this peer already knows from this group. NULL if this + * client is unable to support replay. + * @param message_cb + * Function to be called for all message fragments we + * receive from the group, excluding those our @a replay_cb + * already has. + * @param cls + * Closure for callbacks. + * + * @return Handle for the member, NULL on error. */ struct GNUNET_MULTICAST_Member * -GNUNET_MULTICAST_member_join (const struct GNUNET_CONFIGURATION_Handle *cfg, - void *cls, - const struct GNUNET_CRYPTO_EccPublicKey *pub_key, - uint64_t max_known_message_id, - uint64_t max_known_state_message_id, - GNUNET_MULTICAST_ReplayCallback replay_cb, - GNUNET_MULITCAST_MembershipTestCallback test_cb, - GNUNET_MULTICAST_MulticastMessageCallback message_cb, - const struct GNUNET_MessageHeader *join_req); - +GNUNET_MULTICAST_member_join (const struct GNUNET_CONFIGURATION_Handle *cfg, + const struct GNUNET_CRYPTO_EddsaPublicKey *group_key, + const struct GNUNET_CRYPTO_EcdsaPrivateKey *member_pub_key, + const struct GNUNET_PeerIdentity *origin, + uint16_t relay_count, + const struct GNUNET_PeerIdentity *relays, + const struct GNUNET_MessageHeader *join_request, + GNUNET_MULTICAST_JoinRequestCallback join_request_cb, + GNUNET_MULTICAST_JoinDecisionCallback join_decision_cb, + GNUNET_MULTICAST_ReplayFragmentCallback replay_frag_cb, + GNUNET_MULTICAST_ReplayMessageCallback replay_msg_cb, + GNUNET_MULTICAST_MessageCallback message_cb, + void *cls); /** * Handle for a replay request. */ -struct GNUNET_MULTICAST_ReplayRequest; +struct GNUNET_MULTICAST_MemberReplayHandle; /** - * Request a message to be replayed. Useful if messages below - * the 'max_known_*_id's given when joining are needed and not - * known to the client. + * Request a fragment to be replayed by fragment ID. + * + * Useful if messages below the @e max_known_fragment_id given when joining are + * needed and not known to the client. + * + * @param member + * Membership handle. + * @param fragment_id + * ID of a message fragment that this client would like to see replayed. + * @param flags + * Additional flags for the replay request. + * It is used and defined by GNUNET_MULTICAST_ReplayFragmentCallback * - * @param member membership handle - * @param message_id ID of a message that this client would like to see replayed - * @param message_cb function to be called for the replayed message - * @param message_cb_cls closure for 'message_cb' - * @return replay request handle, NULL on error + * @return Replay request handle, NULL on error. */ -struct GNUNET_MULTICAST_ReplayRequest * -GNUNET_MULTICAST_member_request_replay (struct GNUNET_MULTICAST_Member *member, - uint64_t message_id, - GNUNET_MULTICAST_MulticastMessageCallback message_cb, - void *message_cb_cls); +struct GNUNET_MULTICAST_MemberReplayHandle * +GNUNET_MULTICAST_member_replay_fragment (struct GNUNET_MULTICAST_Member *member, + uint64_t fragment_id, + uint64_t flags); + + +/** + * Request a message fr to be replayed. + * + * Useful if messages below the @e max_known_fragment_id given when joining are + * needed and not known to the client. + * + * @param member + * Membership handle. + * @param message_id + * ID of the message this client would like to see replayed. + * @param fragment_offset + * Offset of the fragment within the message to replay. + * @param flags + * Additional flags for the replay request. + * It is used & defined by GNUNET_MULTICAST_ReplayMessageCallback + * + * @return Replay request handle, NULL on error. + */ +struct GNUNET_MULTICAST_MemberReplayHandle * +GNUNET_MULTICAST_member_replay_message (struct GNUNET_MULTICAST_Member *member, + uint64_t message_id, + uint64_t fragment_offset, + uint64_t flags); /** * Cancel a replay request. * - * @param rr request to cancel + * @param rh + * Request to cancel. */ void -GNUNET_MULTICAST_member_request_replay_cancel (struct GNUNET_MULTICAST_ReplayRequest *rr); +GNUNET_MULTICAST_member_replay_cancel (struct GNUNET_MULTICAST_MemberReplayHandle *rh); /** - * Leave a mutlicast group. + * Part a multicast group. * - * @param member membership handle + * Disconnects from all group members and invalidates the @a member handle. + * + * An application-dependent part message can be transmitted beforehand using + * #GNUNET_MULTICAST_member_to_origin()) + * + * @param member + * Membership handle. */ void -GNUNET_MULTICAST_member_leave (struct GNUNET_MULTICAST_Member *member); +GNUNET_MULTICAST_member_part (struct GNUNET_MULTICAST_Member *member, + GNUNET_ContinuationCallback part_cb, + void *part_cls); /** - * Handle for a message to be delivered to the origin. + * Function called to provide data for a transmission from a member to the origin. + * + * Note that returning #GNUNET_OK or #GNUNET_SYSERR (but not #GNUNET_NO) + * invalidates the respective transmission handle. + * + * @param cls + * Closure. + * @param[in,out] data_size + * Initially set to the number of bytes available in + * @a data, should be set to the number of bytes written to data. + * @param[out] data + * Where to write the body of the message to give to the + * method. The function must copy at most @a data_size bytes to @a data. + * + * @return #GNUNET_SYSERR on error (fatal, aborts transmission) + * #GNUNET_NO on success, if more data is to be transmitted later. + * Should be used if @a data_size was not big enough to take all the + * data. If 0 is returned in @a data_size the transmission is paused, + * and can be resumed with GNUNET_MULTICAST_member_to_origin_resume(). + * #GNUNET_YES if this completes the transmission (all data supplied) + * @deprecated should move to MQ-style API! */ -struct GNUNET_MULTICAST_ResponseRequest; +typedef int +(*GNUNET_MULTICAST_MemberTransmitNotify) (void *cls, + size_t *data_size, + void *data); /** - * Send a message to the origin of the multicast group. - * - * @param member membership handle - * @param size number of bytes we want to send to origin - * @param cb callback to call to get the message - * @param cb_cls closure for 'cb' - * @return handle to cancel request, NULL on error (i.e. request already pending) + * Handle for a message to be delivered from a member to the origin. */ -struct GNUNET_MULTICAST_ResponseRequest * -GNUNET_MULTICAST_member_message_to_origin (struct GNUNET_MULTICAST_Member *member, - size_t size, - GNUNET_CONNECTION_TransmitReadyNotify cb, - void *cb_cls); +struct GNUNET_MULTICAST_MemberTransmitHandle; /** - * Cancel request for message transmission to origin. + * Send a message to the origin of the multicast group. * - * @param rr request to cancel + * @param member + * Membership handle. + * @param request_id + * Application layer ID for the request. Opaque to multicast. + * @param notify + * Callback to call to get the message. + * @param notify_cls + * Closure for @a notify. + * + * @return Handle to cancel request, NULL on error (i.e. request already pending). + * @deprecated should move to MQ-style API! + */ +struct GNUNET_MULTICAST_MemberTransmitHandle * +GNUNET_MULTICAST_member_to_origin (struct GNUNET_MULTICAST_Member *member, + uint64_t request_id, + GNUNET_MULTICAST_MemberTransmitNotify notify, + void *notify_cls); + + +/** + * Resume message transmission to origin. + * + * @param th + * Transmission to cancel. */ void -GNUNET_MULTICAST_member_message_to_origin_cancel (struct GNUNET_MULTICAST_ResponseRequest *rr); +GNUNET_MULTICAST_member_to_origin_resume (struct GNUNET_MULTICAST_MemberTransmitHandle *th); +/** + * Cancel request for message transmission to origin. + * + * @param th + * Transmission to cancel. + */ +void +GNUNET_MULTICAST_member_to_origin_cancel (struct GNUNET_MULTICAST_MemberTransmitHandle *th); + #if 0 /* keep Emacsens' auto-indent happy */ { @@ -571,4 +919,5 @@ GNUNET_MULTICAST_member_message_to_origin_cancel (struct GNUNET_MULTICAST_Respon /* ifndef GNUNET_MULTICAST_SERVICE_H */ #endif -/* end of gnunet_multicast_service.h */ + +/** @} */ /* end of group */