/*
This file is part of GNUnet.
- (C) 2012, 2013 Christian Grothoff (and other contributing authors)
+ Copyright (C) 2012, 2013 Christian Grothoff (and other contributing authors)
GNUnet is free software; you can redistribute it and/or modify
it under the terms of the GNU General Public License as published
* @file include/gnunet_multicast_service.h
* @brief multicast service; establish tunnels to distant peers
* @author Christian Grothoff
+ * @author Gabor X Toth
*/
#ifndef GNUNET_MULTICAST_SERVICE_H
*/
#define GNUNET_MULTICAST_VERSION 0x00000000
-
/**
* Opaque handle for a multicast group 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_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.
+ *
+ * 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.
*
- * @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'
+ * Implementations of this function must call GNUNET_MULTICAST_join_decision()
+ * with the decision.
+ *
+ * @param cls Closure.
+ * @param member_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_JoinRequestCallback) (void *cls,
+ const struct GNUNET_CRYPTO_EcdsaPublicKey *member_key,
+ const struct GNUNET_MessageHeader *join_msg,
+ struct GNUNET_MULTICAST_JoinHandle *jh);
+
+
+/**
+ * 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);
+
+
+/**
+ * Handle to pass back for the answer of a membership test.
*/
-typedef int (*GNUNET_MULTICAST_MembershipChangeCallback)(void *cls,
- const struct GNUNET_PeerIdentity *peer,
- const struct GNUNET_MessageHeader *join_req,
- int is_joining,
- struct GNUNET_MULTICAST_JoinHandle *jh);
+struct GNUNET_MULTICAST_MembershipTestHandle;
+
+
+/**
+ * Call informing multicast about the decision taken for a membership test.
+ *
+ * @param mth Handle that was given for the query.
+ * @param result #GNUNET_YES if peer was a member, #GNUNET_NO if peer was not a member,
+ * #GNUNET_SYSERR if we cannot answer the membership test.
+ */
+void
+GNUNET_MULTICAST_membership_test_result (struct GNUNET_MULTICAST_MembershipTestHandle *mth,
+ int result);
/**
* Method called to test if a member was in the group at a particular time.
*
- * @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 group_generation the generation of the group for which we want to do the test
- * @return GNUNET_YES if peer was a member, GNUNET_NO if peer was not a member,
- * GNUNET_SYSERR if we cannot answer the membership test
+ * It is called when a replay request is received to determine if the requested
+ * message can be replayed.
+ *
+ * @param cls Closure.
+ * @param member_key Identity of the member that we want to test.
+ * @param message_id Message ID for which to perform the test.
+ * @param group_generation Group generation of the message. It has relevance if
+ * the message consists of multiple fragments with different group
+ * generations.
+ * @param mth Handle to give to GNUNET_MULTICAST_membership_test_answer().
*/
-typedef int (*GNUNET_MULTICAST_MembershipTestCallback)(void *cls,
- const struct GNUNET_PeerIdentity *peer,
- uint64_t message_id,
- uint64_t group_generation);
+typedef void
+(*GNUNET_MULTICAST_MembershipTestCallback) (void *cls,
+ const struct GNUNET_CRYPTO_EcdsaPublicKey *member_key,
+ uint64_t message_id,
+ uint64_t group_generation,
+ struct GNUNET_MULTICAST_MembershipTestHandle *mth);
/**
- * Function called whenever a group member has transmitted a message
+ * Function called whenever a group member has transmitted a request
* to the origin (other than joining or leaving).
*
- * @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
+ * 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)
*/
-typedef void (*GNUNET_MULTICAST_ResponseCallback) (void *cls,
- const struct GNUNET_PeerIdentity *sender,
- uint64_t response_id,
- const struct GNUNET_MessageHeader *msg);
+typedef void
+(*GNUNET_MULTICAST_MessageCallback) (void *cls,
+ const struct GNUNET_MULTICAST_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.
+ * Function called with the result of an asynchronous operation.
*
- * @param cls closure (set from GNUNET_MULTICAST_member_join)
- * @param message_id unique number of the message
- * @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)
+ * @see GNUNET_MULTICAST_replay_fragment()
+ *
+ * @param result Result of the operation.
*/
-typedef void (*GNUNET_MULTICAST_MessageCallback) (void *cls,
- uint64_t message_id,
- const struct GNUNET_MULTICAST_MessageHeader *msg);
+typedef void
+(*GNUNET_MULTICAST_ResultCallback) (void *cls,
+ int result);
/**
- * 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).
+ * 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 cfg configuration to use
- * @param cls closure for the various callbacks that follow
+ * @param cls Closure (set from GNUNET_MULTICAST_origin_start()
+ * or GNUNET_MULTICAST_member_join()).
+ * @param member_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_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_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_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 unknown/error.
+ * @param ec Error code.
+ */
+void
+GNUNET_MULTICAST_replay_response (struct GNUNET_MULTICAST_ReplayHandle *rh,
+ const struct GNUNET_MessageHeader *msg,
+ enum GNUNET_MULTICAST_ReplayErrorCode ec);
+
+
+/**
+ * Indicate the end of the replay session.
+ *
+ * Invalidates the replay handle.
+ *
+ * @param rh Replay session to end.
+ */
+void
+GNUNET_MULTICAST_replay_response_end (struct GNUNET_MULTICAST_ReplayHandle *rh);
+
+
+/**
+ * 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.
+ *
+ * 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 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 (one at a time).
+ *
+ * @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; 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
+ * 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 member_test_cb Function multicast can use to test group membership.
+ * @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.
+ * @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_MembershipTestCallback member_test_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)
+ */
+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
+ * 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).
*/
-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_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
+ * @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 mem_test_cb Function multicast can use to test group membership.
+ * @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_MessageCallback 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_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_MembershipTestCallback mem_test_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 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
+ * @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 the replay callback. FIXME: which replay callback? FIXME: use enum?
+ * FIXME: why not pass reply cb here?
+ * @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_MessageCallback 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 the replay callback.
+ * @param result_cb Function to be called for the replayed message.
+ * @param result_cb_cls Closure for @a result_cb.
+ * @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,
+ GNUNET_MULTICAST_ResultCallback result_cb,
+ void *result_cb_cls);
/**
* 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.
+ *
+ * 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
+ * @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);
+
+
+/**
+ * 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)
+ */
+typedef int
+(*GNUNET_MULTICAST_MemberTransmitNotify) (void *cls,
+ size_t *data_size,
+ void *data);
/**
- * Handle for a message to be delivered to the origin.
+ * Handle for a message to be delivered from a member to the origin.
*/
-struct GNUNET_MULTICAST_ResponseRequest;
+struct GNUNET_MULTICAST_MemberTransmitHandle;
/**
- * 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)
+ * Send a message to the origin of the multicast group.
+ *
+ * @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).
*/
-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 *
+GNUNET_MULTICAST_member_to_origin (struct GNUNET_MULTICAST_Member *member,
+ uint64_t request_id,
+ GNUNET_MULTICAST_MemberTransmitNotify notify,
+ void *notify_cls);
/**
- * Cancel request for message transmission to origin.
+ * Resume message transmission to origin.
*
- * @param rr request to cancel
+ * @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 */
{
projects / oweals / gnunet.git / blobdiff