/*
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
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.
+ Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor,
+ Boston, MA 02110-1301, USA.
*/
/**
- * @file include/gnunet_psyc_service.h
- * @brief PSYC service; high-level access to the PSYC protocol
- * note that clients of this API are NOT expected to
- * understand the PSYC message format, only the semantics!
- * Parsing (and serializing) the PSYC stream format is done
- * within the implementation of the libgnunetpsyc library,
- * and this API deliberately exposes as little as possible
- * of the actual data stream format to the application!
+ * @author Gabor X Toth
* @author Christian Grothoff
*
+ * @file
+ * PSYC service
+ *
+ * @defgroup psyc PSYC service
+ * Send/receive messages in PSYC channels and access the PSYC Store.
+ *
+ * Note that clients of this API are NOT expected to understand the PSYC message
+ * format, only the semantics! Parsing (and serializing) the PSYC stream format
+ * is done within the implementation of the libgnunetpsyc library, and this API
+ * deliberately exposes as little as possible of the actual data stream format
+ * to the application!
+ *
* NOTE:
- * - this API does not know about psyc's "root" and "places";
- * there is no 'root' in GNUnet-Psyc as we're decentralized;
- * 'places' and 'persons' are combined within the same
+ * - this API does not know about PSYC's "root" and "places";
+ * there is no 'root' in GNUnet-PSYC as we're decentralized;
+ * 'places' and 'persons' are combined within the same
* abstraction, that of a "channel". Channels are identified
- * and accessed in this API using a public/private key.
- * Higher-level applications should use NAMES within GADS
- * to obtain public keys, and the distinction between
+ * and accessed in this API using a public/private key.
+ * Higher-level applications should use NAMES within GNS
+ * to obtain public keys, and the distinction between
* 'places' and 'persons' can then be made with the help
* of the naming system (and/or conventions).
* Channels are (as in PSYC) organized into a hierarchy; each
- * channel owner (the one with the private key) is then
- * the operator of the multicast group (its Origin in
+ * channel master (the one with the private key) is then
+ * the operator of the multicast group (its Origin in
* the terminology of the multicast API).
* - The API supports passing large amounts of data using
* 'streaming' for the argument passed to a method. State
* and variables must fit into memory and cannot be streamed
- * (thus, no passing of 4 GB of data in a variable;
+ * (thus, no passing of 4 GB of data in a variable;
* once we implement this, we might want to create a
- * #define for the maximum size of a variable).
+ * @c \#define for the maximum size of a variable).
* - PSYC defines standard variables, methods, etc. This
* library deliberately abstracts over all of these; a
- * higher-level API should combine the naming system (GADS)
- * and standard methods (message, join, leave, warn,
- * fail, error) and variables (action, color, time,
- * tag, etc.). However, this API does take over the
- * routing variables, specifically 'context' (channel),
- * and 'source'. We only kind-of support 'target', as
+ * higher-level API should combine the naming system (GNS)
+ * and standard methods (_converse, _notice, _request,
+ * _warning, _error etc) and variables (_action, _color,
+ * _time, etc). However, this API does take over the
+ * routing variables, specifically '_context' (channel),
+ * and '_source'. We only kind-of support '_target', as
* the target is either everyone in the group or the
* origin, and never just a single member of the group;
* for such individual messages, an application needs to
- * construct an 'inbox' channel where the owner (only)
+ * construct an 'inbox' channel where the master (only)
* receives messages (but never forwards; private responses
* would be transmitted by joining the senders 'inbox'
* channel -- or a inbox#bob subchannel). The
- * goal for all of this is to keep the abstractions in this
+ * goal for all of this is to keep the abstractions in this
* API minimal: interaction with multicast, try \& slice,
* state/variable/channel management. Higher-level
* operations belong elsewhere (so maybe this API should
* be called 'PSYC-low', whereas a higher-level API
* implementing defaults for standard methods and
* variables might be called 'PSYC-std' or 'PSYC-high'.
+ *
+ * In PSYC terminology this is simply called the "PSYC
+ * routing layer" and the abstractions, for instance in
+ * psyced, are quite similar. The higher one is called
+ * "PSYC entity layer." In the text rendering of the
+ * protocol the two are separated by an empty line. See
+ * http://about.psyc.eu/Spec:Packet and related. --lynX
+ *
+ * @{
*/
#ifndef GNUNET_PSYC_SERVICE_H
#include "gnunet_util_lib.h"
#include "gnunet_multicast_service.h"
-
+//Mingw work around
+#ifdef MINGW
+ # ifndef UINT64_MAX
+ # define UINT64_MAX 0xffffffffffffffffULL
+ # endif
+#endif
/**
* Version number of GNUnet-PSYC API.
/**
- * Method called from PSYC upon receiving a message indicating a call
- * to a 'method'.
+ * Policy flags for a channel.
+ */
+enum GNUNET_PSYC_ChannelFlags
+{
+ /**
+ * Admission must be confirmed by the master.
+ */
+ GNUNET_PSYC_CHANNEL_ADMISSION_CONTROL = 1 << 0,
+
+ /**
+ * Past messages are only available to slaves who were admitted at the time
+ * they were sent to the channel.
+ */
+ GNUNET_PSYC_CHANNEL_RESTRICTED_HISTORY = 1 << 1
+};
+
+
+/**
+ * PSYC channel policies.
+ */
+enum GNUNET_PSYC_Policy
+{
+ /**
+ * Anyone can join the channel, without announcing his presence;
+ * all messages are always public and can be distributed freely.
+ * Joins may be announced, but this is not required.
+ */
+ GNUNET_PSYC_CHANNEL_ANONYMOUS = 0,
+
+ /**
+ * The master must approve membership to the channel, messages must only be
+ * distributed to current channel slaves. This includes the channel
+ * state as well as transient messages.
+ */
+ GNUNET_PSYC_CHANNEL_PRIVATE
+ = GNUNET_PSYC_CHANNEL_ADMISSION_CONTROL
+ | GNUNET_PSYC_CHANNEL_RESTRICTED_HISTORY
+
+#if IDEAS_FOR_FUTURE
+ /**
+ * Anyone can freely join the channel (no approval required);
+ * however, messages must only be distributed to current channel
+ * slaves, so the master must still acknowledge that the slave
+ * joined before transient messages are delivered. As approval is
+ * guaranteed, the presistent channel state can be synchronized freely
+ * immediately, prior to master confirmation.
+ */
+ GNUNET_PSYC_CHANNEL_OPEN
+ = GNUNET_PSYC_CHANNEL_RESTRICTED_HISTORY,
+
+ /**
+ * The master must approve joins to the channel, but past messages can be
+ * freely distributed to slaves.
+ */
+ GNUNET_PSYC_CHANNEL_CLOSED
+ = GNUNET_PSYC_CHANNEL_ADMISSION_CONTROL,
+#endif
+};
+
+
+enum GNUNET_PSYC_MessageFlags
+{
+ /**
+ * Default / no flags.
+ */
+ GNUNET_PSYC_MESSAGE_DEFAULT = 0,
+
+ /**
+ * Historic message, retrieved from PSYCstore.
+ */
+ GNUNET_PSYC_MESSAGE_HISTORIC = 1 << 0,
+
+ /**
+ * Request from slave to master.
+ */
+ GNUNET_PSYC_MESSAGE_REQUEST = 1 << 1,
+
+ /**
+ * Message can be delivered out of order.
+ */
+ GNUNET_PSYC_MESSAGE_ORDER_ANY = 1 << 2
+};
+
+
+/**
+ * Values for the @a state_delta field of GNUNET_PSYC_MessageHeader.
+ */
+enum GNUNET_PSYC_StateDeltaValues
+{
+ GNUNET_PSYC_STATE_RESET = 0,
+
+ GNUNET_PSYC_STATE_NOT_MODIFIED = UINT64_MAX
+};
+
+
+GNUNET_NETWORK_STRUCT_BEGIN
+
+/**
+ * A PSYC message.
*
- * @param cls closure
- * @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 sender who transmitted the message (origin, except for messages
- * from one of the members to the origin)
- * @param message_id unique message counter for this message;
- * (unique only in combination with the given sender for
- * this channel)
- * @param group_generation group generation counter for this message
- * (always zero for messages from members to channel owner)
- * @param data_size number of bytes in 'data'
- * @param data data stream given to the method (might not be zero-terminated
- * if data is binary)
+ * Used for single-fragment messages e.g. in a join request or response.
*/
-typedef int (*GNUNET_PSYC_Method)(void *cls,
- const char *full_method_name,
- const struct GNUNET_PeerIdentity *sender,
- uint64_t message_id,
- uint64_t group_generation,
- size_t data_size,
- const void *data);
+struct GNUNET_PSYC_Message
+{
+ /**
+ * Message header with size and type information.
+ */
+ struct GNUNET_MessageHeader header;
+
+ /* Followed by concatenated PSYC message parts:
+ * messages with GNUNET_MESSAGE_TYPE_PSYC_MESSAGE_* types
+ */
+};
/**
- * Handle for the channel of a PSYC group.
+ * Header of a PSYC message.
+ *
+ * The PSYC service adds this when delivering the message to local clients,
+ * not present on the multicast layer.
*/
-struct GNUNET_PSYC_Channel;
+struct GNUNET_PSYC_MessageHeader
+{
+ /**
+ * Generic message header with size and type information.
+ */
+ struct GNUNET_MessageHeader header;
+
+ /**
+ * Flags for this message fragment.
+ *
+ * @see enum GNUNET_PSYC_MessageFlags
+ */
+ uint32_t flags GNUNET_PACKED;
+
+ /**
+ * Number of the message this message part belongs to.
+ * Monotonically increasing from 1.
+ */
+ uint64_t message_id GNUNET_PACKED;
+
+ /**
+ * Byte offset of this @e fragment of the @e message.
+ */
+ uint64_t fragment_offset GNUNET_PACKED;
+
+ /**
+ * Sending slave's public key.
+ * Not set if the message is from the master.
+ */
+ struct GNUNET_CRYPTO_EcdsaPublicKey slave_pub_key;
+
+ /* Followed by concatenated PSYC message parts:
+ * messages with GNUNET_MESSAGE_TYPE_PSYC_MESSAGE_* types
+ */
+};
/**
- * Start a PSYC channel. Will create a multicast group identified by
- * the given ECC key. Messages recevied from group members will be
- * given to the respective handler methods. If a new member wants to
- * join a group, the "join" method handler will be invoked; the join
- * handler must then generate a "join" message to approve the joining
- * of the new member. The channel can also change group membership
- * without explicit requests. Note that PSYC doesn't itself "understand"
- * join or leave messages, the respective methods must call other
- * PSYC functions to inform PSYC about the meaning of the respective
- * events.
- *
- * @param cfg configuration to use (to connect to PSYC service)
- * @param parent parent channel, NULL for top-level channels
- * @param name name of the channel, only important if this is a subchannel
- * @param method_count number of methods in 'methods' array
- * @param methods functions to invoke on messages received from members,
- * typcially at least contains functions for 'join' and 'leave'.
- * @param priv_key ECC key that will be used to sign messages for this
- * PSYC session; public key is used to identify the
- * PSYC group; FIXME: we'll likely want to use
- * NOT the p521 curve here, but a cheaper one in the future
- * Note that end-users will usually not use the private key
- * directly, but rather look it up in GADS for groups
- * managed by other users, or select a file with the private
- * key(s) when setting up their own channels
- * @param join_policy what is the membership policy of the group?
- * Used to automate group management decisions.
- * @return handle for the channel, NULL on error
+ * The method of a message.
*/
-struct GNUNET_PSYC_Channel *
-GNUNET_PSYC_channel_start (const struct GNUNET_CONFIGURATION_Handle *cfg,
- struct GNUNET_PSYC_Channel *parent,
- const char *name,
- unsigned int method_count,
- const struct GNUNET_PSYC_Method *methods,
- const struct GNUNET_CRYPTO_EccPrivateKey *priv_key,
- enum GNUNET_MULTICAST_JoinPolicy join_policy);
+struct GNUNET_PSYC_MessageMethod
+{
+ /**
+ * Type: GNUNET_MESSAGE_TYPE_PSYC_MESSAGE_METHOD
+ */
+ struct GNUNET_MessageHeader header;
+
+ /**
+ * OR'ed GNUNET_PSYC_MasterTransmitFlags
+ */
+ uint32_t flags GNUNET_PACKED;
+
+ /**
+ * Number of message IDs since the last message that contained state
+ * operations. @see enum GNUNET_PSYC_StateDeltaValues
+ */
+ uint64_t state_delta GNUNET_PACKED;
+
+ /* Followed by NUL-terminated method name. */
+};
/**
- * Possible operations on PSYC state (persistent) and variables (per message).
+ * A modifier of a message.
*/
-enum GNUNET_PSYC_Operator
+struct GNUNET_PSYC_MessageModifier
{
/**
- * Replace the full state with the new value ("=").
+ * Type: GNUNET_MESSAGE_TYPE_PSYC_MESSAGE_MODIFIER
*/
- GNUNET_PSYC_SOT_SET_STATE = 0,
-
+ struct GNUNET_MessageHeader header;
+
/**
- * Delete the complete entry from the state (given data must be
- * empty). Equivalent to 'SET' with emtpy data, but more
- * explicit ("=");
+ * Size of value.
*/
- GNUNET_PSYC_SOT_DELETE = 0,
-
+ uint32_t value_size GNUNET_PACKED;
+
/**
- * Set the value of a variable to a new value (":").
+ * Size of name, including NUL terminator.
*/
- GNUNET_PSYC_SOT_SET_VARIABLE,
-
+ uint16_t name_size GNUNET_PACKED;
+
/**
- * Add the given value to the set of values in the state ("+").
+ * enum GNUNET_PSYC_Operator
*/
- GNUNET_PSYC_SOT_ADD_STATE,
-
+ uint8_t oper;
+
+ /* Followed by NUL-terminated name, then the value. */
+};
+
+
+struct GNUNET_PSYC_CountersResultMessage
+{
+ /**
+ * Type: GNUNET_MESSAGE_TYPE_PSYC_RESULT_COUNTERS
+ */
+ struct GNUNET_MessageHeader header;
+
/**
- * Remove the given value from the set of values in the state ("-").
+ * Status code for the operation.
*/
- GNUNET_PSYC_SOT_REMOVE_STATE
-
+ uint32_t result_code GNUNET_PACKED;
+
+ /**
+ * Last message ID sent to the channel.
+ */
+ uint64_t max_message_id GNUNET_PACKED;
};
/**
- * Update channel state (or set a variable). The state of a channel
- * must fit into the memory of each member (and the channel); large
- * values that require streaming must only be passed as the stream
- * arguments to methods. State updates might not be transmitted to
- * group members until the next call to
- * 'GNUNET_PSYC_channel_broadcast_call_method'. Variable updates must
- * be given just before the call to the respective method that needs
- * the variables.
- *
- * @param channel handle to the PSYC group / channel
- * @param full_state_name name of the field in the channel state to change
- * @param type kind of update operation (add, remove, replace, delete)
- * @param data_size number of bytes in data
- * @param data new state value
- * @return GNUNET_OK on success, GNUNET_SYSERR on internal error
- * (i.e. state too large)
+ * Join request sent to a PSYC master.
*/
-int
-GNUNET_PSYC_channel_update (struct GNUNET_PSYC_Channel *channel,
- const char *full_state_name,
- enum GNUNET_PSYC_Operator type,
- size_t data_size,
- const void *data);
+struct GNUNET_PSYC_JoinRequestMessage
+{
+ /**
+ * Type: GNUNET_MESSAGE_TYPE_PSYC_MASTER_JOIN_REQUEST
+ */
+ struct GNUNET_MessageHeader header;
+ /**
+ * Public key of the joining slave.
+ */
+ struct GNUNET_CRYPTO_EcdsaPublicKey slave_pub_key;
+
+ /* Followed by struct GNUNET_MessageHeader join_request */
+};
/**
- * Function called to provide data for a transmission via PSYC. Note
- * that returning GNUNET_OK or GNUNET_SYSERR (but not GNUNET_NO)
- * invalidates the respective transmission handle.
- *
- * @param cls closure
- * @param message_id set to the unique message ID that was generated for
- * this message
- * @param group_generation set to the group generation used for this
- * message
- * @param data_size initially set to the number of bytes available in 'data',
- * should be set to the number of bytes written to data (IN/OUT)
- * @param data where to write the body of the message to give to the method;
- * function must copy at most '*data_size' bytes to '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 'data_size' was not big enough to take all the data)
- * GNUNET_OK if this completes the transmission (all data supplied)
+ * Join decision sent in reply to a join request.
+ */
+struct GNUNET_PSYC_JoinDecisionMessage
+{
+ /**
+ * Type: GNUNET_MESSAGE_TYPE_PSYC_JOIN_DECISION
+ */
+ struct GNUNET_MessageHeader header;
+
+ /**
+ * #GNUNET_YES if the slave was admitted.
+ */
+ int32_t is_admitted;
+
+ /**
+ * Public key of the joining slave.
+ * Only set when the master is sending the decision,
+ * not set when a slave is receiving it.
+ */
+ struct GNUNET_CRYPTO_EcdsaPublicKey slave_pub_key;
+
+ /* Followed by struct GNUNET_MessageHeader join_response */
+};
+
+
+enum GNUNET_PSYC_HistoryReplayFlags
+{
+ /**
+ * Replay locally available messages.
+ */
+ GNUNET_PSYC_HISTORY_REPLAY_LOCAL = 0,
+
+ /**
+ * Replay messages from remote peers if not found locally.
+ */
+ GNUNET_PSYC_HISTORY_REPLAY_REMOTE = 1,
+};
+
+
+struct GNUNET_PSYC_HistoryRequestMessage
+{
+ /**
+ * Type: GNUNET_MESSAGE_TYPE_PSYC_CHANNEL_HISTORY_REPLAY
+ */
+ struct GNUNET_MessageHeader header;
+
+ /**
+ * @see enum GNUNET_PSYC_HistoryReplayFlags
+ */
+ uint32_t flags GNUNET_PACKED;
+
+ /**
+ * ID for this operation.
+ */
+ uint64_t op_id GNUNET_PACKED;
+
+ uint64_t start_message_id GNUNET_PACKED;
+
+ uint64_t end_message_id GNUNET_PACKED;
+
+ uint64_t message_limit GNUNET_PACKED;
+
+ /* Followed by NUL-terminated method name prefix. */
+};
+
+
+struct GNUNET_PSYC_StateRequestMessage
+{
+ /**
+ * Types:
+ * - GNUNET_MESSAGE_TYPE_PSYC_CHANNEL_STATE_GET
+ * - GNUNET_MESSAGE_TYPE_PSYC_CHANNEL_STATE_GET_PREFIX
+ */
+ struct GNUNET_MessageHeader header;
+
+ uint32_t reserved GNUNET_PACKED;
+
+ /**
+ * ID for this operation.
+ */
+ uint64_t op_id GNUNET_PACKED;
+
+ /* Followed by NUL-terminated name. */
+};
+
+
+/**** service -> library ****/
+
+
+/**
+ * Answer from service to client about last operation.
*/
-typedef int (*GNUNET_PSYC_ChannelReadyNotify)(void *cls,
- uint64_t message_id,
- uint64_t group_generation,
- size_t *data_size,
- void *data);
+struct GNUNET_PSYC_OperationResultMessage
+{
+ /**
+ * Types:
+ * - GNUNET_MESSAGE_TYPE_PSYC_RESULT_CODE
+ * - GNUNET_MESSAGE_TYPE_PSYC_CHANNEL_STATE_RESULT
+ */
+ struct GNUNET_MessageHeader header;
+
+ uint32_t reserved GNUNET_PACKED;
+
+ /**
+ * Operation ID.
+ */
+ uint64_t op_id GNUNET_PACKED;
+
+ /**
+ * Status code for the operation.
+ */
+ uint64_t result_code GNUNET_PACKED;
+
+ /* Followed by:
+ * - on error: NUL-terminated error message
+ * - on success: one of the following message types
+ *
+ * For a STATE_RESULT, one of:
+ * - GNUNET_MESSAGE_TYPE_PSYC_MESSAGE_MODIFIER
+ * - GNUNET_MESSAGE_TYPE_PSYC_MESSAGE_MOD_CONT
+ * - GNUNET_MESSAGE_TYPE_PSYC_MESSAGE_END
+ */
+};
+
+GNUNET_NETWORK_STRUCT_END
+
+
+#define GNUNET_PSYC_MODIFIER_MAX_PAYLOAD \
+ GNUNET_MULTICAST_FRAGMENT_MAX_PAYLOAD \
+ - sizeof (struct GNUNET_PSYC_MessageModifier)
+
+#define GNUNET_PSYC_MOD_CONT_MAX_PAYLOAD \
+ GNUNET_MULTICAST_FRAGMENT_MAX_PAYLOAD \
+ - sizeof (struct GNUNET_MessageHeader)
+
+#define GNUNET_PSYC_DATA_MAX_PAYLOAD \
+ GNUNET_MULTICAST_FRAGMENT_MAX_PAYLOAD \
+ - sizeof (struct GNUNET_MessageHeader)
/**
- * Handle for a pending PSYC transmission operation.
+ * PSYC message part processing states.
*/
-struct GNUNET_PSYC_ChannelTransmitHandle;
+enum GNUNET_PSYC_MessageState
+{
+ GNUNET_PSYC_MESSAGE_STATE_START = 0,
+ GNUNET_PSYC_MESSAGE_STATE_HEADER = 1,
+ GNUNET_PSYC_MESSAGE_STATE_METHOD = 2,
+ GNUNET_PSYC_MESSAGE_STATE_MODIFIER = 3,
+ GNUNET_PSYC_MESSAGE_STATE_MOD_CONT = 4,
+ GNUNET_PSYC_MESSAGE_STATE_DATA = 5,
+ GNUNET_PSYC_MESSAGE_STATE_END = 6,
+ GNUNET_PSYC_MESSAGE_STATE_CANCEL = 7,
+ GNUNET_PSYC_MESSAGE_STATE_ERROR = 8,
+};
/**
- * Send a message to call a method to all members in the PSYC channel
- * (and all parent channels if this is a subchannel).
+ * Handle that identifies a join request.
*
- * @param channel handle to the PSYC multicast group
- * @param increment_group_generation GNUNET_YES if we need to increment
- * the group generation counter after transmitting this message
- * @param full_method_name which method should be invoked
- * @param notify function to call to obtain the arguments
- * @param notify_cls closure for 'notify'
- * @return transmission handle, NULL on error (i.e. more than one request queued)
+ * Used to match calls to #GNUNET_PSYC_JoinCallback to the
+ * corresponding calls to GNUNET_PSYC_join_decision().
*/
-struct GNUNET_PSYC_ChannelTransmitHandle *
-GNUNET_PSYC_channel_notify_transmit_ready (struct GNUNET_PSYC_Channel *channel,
- int increment_group_generation,
- const char *full_method_name,
- GNUNET_PSYC_ChannelReadyNotify notify,
- void *notify_cls);
+struct GNUNET_PSYC_JoinHandle;
/**
- * Abort transmission request to channel.
+ * Method called from PSYC upon receiving a message.
*
- * @param th handle of the request that is being aborted
+ * @param cls Closure.
+ * @param message_id Sequence number of the message.
+ * @param flags OR'ed GNUNET_PSYC_MessageFlags
+ * @param msg Message part, one of the following types:
*/
-void
-GNUNET_PSYC_channel_notify_transmit_ready_cancel (struct GNUNET_PSYC_ChannelTransmitHandle *th);
+typedef void
+(*GNUNET_PSYC_MessageCallback) (void *cls,
+ const struct GNUNET_PSYC_MessageHeader *msg);
/**
- * End a PSYC channel. Note that subchannels MUST be ended before
- * their parents.
+ * Method called from PSYC upon receiving part of a message.
*
- * @param channel PSYC channel to terminate
+ * @param cls
+ * Closure.
+ * @param slave_pub_key
+ * Public key of the slave sending the message.
+ * Only set for channel master.
+ * @param message_id
+ * Sequence number of the message.
+ * @param flags
+ * OR'ed GNUNET_PSYC_MessageFlags
+ * @param fragment_offset
+ * Multicast message fragment offset.
+ * @param msg Message part, one of the following types:
+ * - #GNUNET_MESSAGE_TYPE_PSYC_MESSAGE_HEADER
+ * - #GNUNET_MESSAGE_TYPE_PSYC_MESSAGE_METHOD
+ * - #GNUNET_MESSAGE_TYPE_PSYC_MESSAGE_MODIFIER
+ * - #GNUNET_MESSAGE_TYPE_PSYC_MESSAGE_MOD_CONT
+ * - #GNUNET_MESSAGE_TYPE_PSYC_MESSAGE_DATA
+ * or NULL if an error occurred while receiving a message.
*/
-void
-GNUNET_PSYC_channel_end (struct GNUNET_PSYC_Channel *channel);
+typedef void
+(*GNUNET_PSYC_MessagePartCallback) (void *cls,
+ const struct GNUNET_PSYC_MessageHeader *msg,
+ const struct GNUNET_MessageHeader *pmsg);
/**
- * Handle to access PSYC group operations for all members.
+ * Method called from PSYC upon receiving a join request.
+ *
+ * @param cls
+ * Closure.
+ * @param slave_pub_key
+ * Public key of the slave requesting join.
+ * @param join_msg
+ * Join message sent along with the request.
+ * @param jh
+ * Join handle to use with GNUNET_PSYC_join_decision()
*/
-struct GNUNET_PSYC_Group;
+typedef void
+(*GNUNET_PSYC_JoinRequestCallback) (void *cls,
+ const struct GNUNET_PSYC_JoinRequestMessage *req,
+ const struct GNUNET_CRYPTO_EcdsaPublicKey *slave_pub_key,
+ const struct GNUNET_PSYC_Message *join_msg,
+ struct GNUNET_PSYC_JoinHandle *jh);
/**
- * Convert 'channel' to a 'group' handle to access the 'group' APIs.
- *
- * @param channel channel handle
- * @return group handle, valid for as long as 'channel' is valid
- */
-struct GNUNET_PSYC_Group *
-GNUNET_PSYC_channel_get_group (struct GNUNET_PSYC_Channel *channel);
+ * Function to call with the decision made for a join request.
+ *
+ * Must be called once and only once in response to an invocation of the
+ * #GNUNET_PSYC_JoinCallback.
+ *
+ * @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 Application-dependent join response message to send along
+ * with the decision.
+ *
+ * @return #GNUNET_OK on success,
+ * #GNUNET_SYSERR if @a join_resp is too large.
+ */
+int
+GNUNET_PSYC_join_decision (struct GNUNET_PSYC_JoinHandle *jh,
+ int is_admitted,
+ uint32_t relay_count,
+ const struct GNUNET_PeerIdentity *relays,
+ const struct GNUNET_PSYC_Message *join_resp);
/**
- * Convert 'member' to a 'group' handle to access the 'group' APIs.
- *
- * @param member membership handle
- * @return group handle, valid for as long as 'member' is valid
- */
-struct GNUNET_PSYC_Group *
-GNUNET_PSYC_member_get_group (struct GNUNET_PSYC_Member *member);
+ * Handle for the master of a PSYC channel.
+ */
+struct GNUNET_PSYC_Master;
/**
- * Add a member to the group. Note that this will NOT generate any
- * PSYC traffic, it will merely update the local data base to modify
- * how we react to 'membership test' queries. The channel still needs to
- * explicitly transmit a 'join' message to notify other group members
- * and they then also must still call this function in their respective
- * methods handling the 'join' message. This way, how 'join' and 'leave'
- * operations are exactly implemented is still up to the application;
- * for example, there might be a 'leave_all' method to kick out everyone.
+ * Function called after connected to the PSYC service
+ * and the channel master started.
*
- * Note that group members are explicitly trusted to execute such
- * methods correctly; not doing so correctly will result in either
- * denying members access or offering access to group data to
- * non-members.
+ * Also called when reconnected to the service
+ * after the connection closed unexpectedly.
*
- * @param group group handle
- * @param member which peer to add
- * @param message_id message ID for the message that changed the membership
- * @param group_generation the generation ID where the change went into effect
+ * @param cls
+ * Closure.
+ * @param result
+ * #GNUNET_YES if there were already messages sent to the channel,
+ * #GNUNET_NO if the message history is empty,
+ * #GNUNET_SYSERR on error.
+ * @param max_message_id
+ * Last message ID sent to the channel.
*/
-void
-GNUNET_PSYC_group_member_admit (struct GNUNET_PSYC_Group *group,
- const struct GNUNET_PeerIdentity *member,
- uint64_t message_id,
- uint64_t group_generation);
+typedef void
+(*GNUNET_PSYC_MasterStartCallback) (void *cls, int result,
+ uint64_t max_message_id);
/**
- * Remove a member from the group. Note that this will NOT generate any
- * PSYC traffic, it will merely update the local data base to modify
- * how we react to 'membership test' queries. The channel still needs to
- * explicitly transmit a 'leave' message to notify other group members
- * and they then also must still call this function in their respective
- * methods handling the 'leave' message. This way, how 'join' and 'leave'
- * operations are exactly implemented is still up to the application;
- * for example, there might be a 'leave_all' message to kick out everyone.
+ * Start a PSYC master channel.
*
- * Note that group members are explicitly trusted to perform these
- * operations correctly; not doing so correctly will result in either
- * denying members access or offering access to group data to
- * non-members.
+ * Will start a multicast group identified by the given ECC key. Messages
+ * received from group members will be given to the respective handler methods.
+ * If a new member wants to join a group, the "join" method handler will be
+ * invoked; the join handler must then generate a "join" message to approve the
+ * joining of the new member. The channel can also change group membership
+ * without explicit requests. Note that PSYC doesn't itself "understand" join
+ * or part messages, the respective methods must call other PSYC functions to
+ * inform PSYC about the meaning of the respective events.
*
- * @param group group handle
- * @param member which peer to remove
- * @param message_id message ID for the message that changed the membership
- * @param group_generation the generation ID where the change went into effect
+ * @param cfg Configuration to use (to connect to PSYC service).
+ * @param channel_key ECC key that will be used to sign messages for this
+ * PSYC session. The public key is used to identify the PSYC channel.
+ * Note that end-users will usually not use the private key directly, but
+ * rather look it up in GNS for places managed by other users, or select
+ * a file with the private key(s) when setting up their own channels
+ * FIXME: we'll likely want to use NOT the p521 curve here, but a cheaper
+ * one in the future.
+ * @param policy Channel policy specifying join and history restrictions.
+ * Used to automate join decisions.
+ * @param master_start_cb Function to invoke after the channel master started.
+ * @param join_request_cb Function to invoke when a slave wants to join.
+ * @param message_cb Function to invoke on message parts sent to the channel
+ * and received from slaves
+ * @param cls Closure for @a method and @a join_cb.
+ *
+ * @return Handle for the channel master, NULL on error.
*/
-void
-GNUNET_PSYC_group_member_kick (struct GNUNET_PSYC_Group *group,
- const struct GNUNET_PeerIdentity *member,
- uint64_t message_id,
- uint64_t group_generation);
+struct GNUNET_PSYC_Master *
+GNUNET_PSYC_master_start (const struct GNUNET_CONFIGURATION_Handle *cfg,
+ const struct GNUNET_CRYPTO_EddsaPrivateKey *channel_key,
+ enum GNUNET_PSYC_Policy policy,
+ GNUNET_PSYC_MasterStartCallback master_start_cb,
+ GNUNET_PSYC_JoinRequestCallback join_request_cb,
+ GNUNET_PSYC_MessageCallback message_cb,
+ GNUNET_PSYC_MessagePartCallback message_part_cb,
+ void *cls);
/**
- * Function called to inform a member about state changes for a
- * channel. Note that (for sets) only the delta is communicated, not
- * the full state.
+ * Function called to provide data for a transmission via PSYC.
*
- * @param cls closure
- * @param full_state_name full name of the state
- * @param type how to interpret the change
- * @param state_value information about the new state
- * @param state_value_size number of bytes in 'state_value'
+ * Note that returning #GNUNET_YES 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_PSYC_master_transmit_resume().
+ * #GNUNET_YES if this completes the transmission (all data supplied)
*/
-typedef void (*GNUNET_PSYC_StateCallback)(void *cls,
- const char *full_state_name,
- enum GNUNET_PSYC_Operator type,
- const void *state_value,
- size_t state_value_size);
+typedef int
+(*GNUNET_PSYC_TransmitNotifyData) (void *cls,
+ uint16_t *data_size,
+ void *data);
+/**
+ * Function called to provide a modifier for a transmission via PSYC.
+ *
+ * Note that returning #GNUNET_YES 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 modifier's name and value.
+ * The function must copy at most @a data_size bytes to @a data.
+ * When this callback is first called for a modifier, @a data should
+ * contain: "name\0value". If the whole value does not fit, subsequent
+ * calls to this function should write continuations of the value to
+ * @a data.
+ * @param[out] oper Where to write the operator of the modifier.
+ * Only needed during the first call to this callback at the beginning
+ * of the modifier. In case of subsequent calls asking for value
+ * continuations @a oper is set to #NULL.
+ * @param[out] full_value_size Where to write the full size of the value.
+ * Only needed during the first call to this callback at the beginning
+ * of the modifier. In case of subsequent calls asking for value
+ * continuations @a value_size is set to #NULL.
+ * @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 for the modifier's value (the name must be always returned
+ * during the first call to this callback).
+ * If 0 is returned in @a data_size the transmission is paused,
+ * and can be resumed with GNUNET_PSYC_master_transmit_resume().
+ * #GNUNET_YES if this completes the modifier (the whole value is supplied).
+ */
+typedef int
+(*GNUNET_PSYC_TransmitNotifyModifier) (void *cls,
+ uint16_t *data_size,
+ void *data,
+ uint8_t *oper,
+ uint32_t *full_value_size);
/**
- * Descriptor for an event handler handling PSYC state updates.
+ * Flags for transmitting messages to a channel by the master.
*/
-struct GNUNET_PSYC_StateHandler
+enum GNUNET_PSYC_MasterTransmitFlags
{
+ GNUNET_PSYC_MASTER_TRANSMIT_NONE = 0,
/**
- * Name of the state this handler calls about, used in try-and-slice matching.
+ * Whether this message should reset the channel state,
+ * i.e. remove all previously stored state variables.
*/
- const char *state_name;
+
+ GNUNET_PSYC_MASTER_TRANSMIT_STATE_RESET = 1 << 0,
/**
- * Function to call whenever the respective state changes.
+ * Whether this message contains any state modifiers.
*/
- GNUNET_PSYC_StateCallback event_handler;
+ GNUNET_PSYC_MASTER_TRANSMIT_STATE_MODIFY = 1 << 1,
/**
- * Closure for the 'event_handler' function.
+ * Add PSYC header variable with the hash of the current channel state.
*/
- void *event_handler_cls;
+ GNUNET_PSYC_MASTER_TRANSMIT_STATE_HASH = 1 << 2,
+ /**
+ * Whether we need to increment the group generation counter after
+ * transmitting this message.
+ */
+ GNUNET_PSYC_MASTER_TRANSMIT_INC_GROUP_GEN = 1 << 3
};
/**
- * Join a PSYC group. The entity joining is always the local peer.
- * The user must immediately use the 'GNUNET_PSYC_member_send_to_host'
- * (and possibly 'GNUNET_PSYC_member_host_variable_set') functions to
- * transmit a 'join_msg' to the channel; if the join request succeeds,
- * the channel state (and 'recent' method calls) will be replayed to
- * the joining member. There is no explicit notification on failure
- * (as the channel may simply take days to approve, and disapproval is
- * simply being ignored).
+ * Handle for a pending PSYC transmission operation.
+ */
+struct GNUNET_PSYC_MasterTransmitHandle;
+
+
+/**
+ * Send a message to call a method to all members in the PSYC channel.
*
- * @param cfg configuration to use
- * @param pub_key ECC key that identifies the channel we wish to join
- * @param method_count number of methods in 'methods' array
- * @param methods functions to invoke on messages received from the channel,
- * typcially at least contains functions for 'join' and 'leave'.
- * @param state_count number of state handlers
- * @param state_handlers array of state event handlers
- * @return handle for the member, NULL on error
+ * @param master Handle to the PSYC channel.
+ * @param method_name Which method should be invoked.
+ * @param notify_mod Function to call to obtain modifiers.
+ * @param notify_data Function to call to obtain fragments of the data.
+ * @param notify_cls Closure for @a notify_mod and @a notify_data.
+ * @param flags Flags for the message being transmitted.
+ * @return Transmission handle, NULL on error (i.e. more than one request queued).
*/
-struct GNUNET_PSYC_Member *
-GNUNET_PSYC_member_join (const struct GNUNET_CONFIGURATION_Handle *cfg,
- const struct GNUNET_CRYPTO_EccPublicKey *pub_key,
- unsigned int method_count,
- const struct GNUNET_PSYC_Method *methods,
- unsigned int state_count,
- struct GNUNET_PSYC_StateHandler *state_handlers);
+struct GNUNET_PSYC_MasterTransmitHandle *
+GNUNET_PSYC_master_transmit (struct GNUNET_PSYC_Master *master,
+ const char *method_name,
+ GNUNET_PSYC_TransmitNotifyModifier notify_mod,
+ GNUNET_PSYC_TransmitNotifyData notify_data,
+ void *notify_cls,
+ enum GNUNET_PSYC_MasterTransmitFlags flags);
/**
- * Leave a multicast group. Will terminate the connection to the PSYC
- * service. Polite clients should first explicitly send a 'leave'
- * request (via 'GNUNET_PSYC_member_send_to_host').
+ * Resume transmission to the channel.
*
- * @param member membership handle
+ * @param th Handle of the request that is being resumed.
*/
void
-GNUNET_PSYC_member_leave (struct GNUNET_PSYC_Member *member);
+GNUNET_PSYC_master_transmit_resume (struct GNUNET_PSYC_MasterTransmitHandle *th);
/**
- * Function called to provide data for a transmission to the channel
- * owner (aka the 'host' of the channel). Note that returning
- * GNUNET_OK or GNUNET_SYSERR (but not GNUNET_NO) invalidates the
- * respective transmission handle.
+ * Abort transmission request to channel.
*
- * @param cls closure
- * @param data_size initially set to the number of bytes available in 'data',
- * should be set to the number of bytes written to data (IN/OUT)
- * @param data where to write the body of the message to give to the method;
- * function must copy at most '*data_size' bytes to 'data'.
- * @return GNUNET_SYSERR on error (fatal, aborts transmission)
- * GNUNET_NO on success, if more data is to be transmitted later
- * GNUNET_OK if this completes the transmission (all data supplied)
+ * @param th Handle of the request that is being aborted.
*/
-typedef int (*GNUNET_PSYC_HostReadyNotify)(void *cls,
- size_t *data_size,
- char *data);
+void
+GNUNET_PSYC_master_transmit_cancel (struct GNUNET_PSYC_MasterTransmitHandle *th);
+
+
+/**
+ * Relay a message
+ *
+ * @param master Handle to the PSYC channel.
+ * @param method_name Which method should be invoked.
+ * @param notify_mod Function to call to obtain modifiers.
+ * @param notify_data Function to call to obtain fragments of the data.
+ * @param notify_cls Closure for @a notify_mod and @a notify_data.
+ * @param flags Flags for the message being transmitted.
+ * @return Transmission handle, NULL on error (i.e. more than one request queued).
+ */
+struct GNUNET_PSYC_MasterTransmitHandle *
+GNUNET_PSYC_master_relay (struct GNUNET_PSYC_Master *master,
+ uint64_t message_id);
+
+
+/**
+ * Stop a PSYC master channel.
+ *
+ * @param master
+ * PSYC channel master to stop.
+ * @param keep_active
+ * Keep place active after last application disconnected.
+ * @param stop_cb
+ * Function called after the master stopped
+ * and disconnected from the psyc service.
+ * @param stop_cls
+ * Closure for @a part_cb.
+ */
+void
+GNUNET_PSYC_master_stop (struct GNUNET_PSYC_Master *master,
+ int keep_active,
+ GNUNET_ContinuationCallback stop_cb,
+ void *stop_cls);
+
+
+/**
+ * Handle for a PSYC channel slave.
+ */
+struct GNUNET_PSYC_Slave;
+
+
+/**
+ * Function called after the slave connected to the PSYC service.
+ *
+ * Also called when reconnected to the service
+ * after the connection closed unexpectedly.
+ *
+ * @param cls
+ * Closure.
+ * @param result
+ * #GNUNET_YES if there were already messages sent to the channel,
+ * #GNUNET_NO if the message history is empty,
+ * #GNUNET_SYSERR on error.
+ * @param max_message_id
+ * Last message ID sent to the channel.
+ */
+typedef void
+(*GNUNET_PSYC_SlaveConnectCallback) (void *cls, int result,
+ uint64_t max_message_id);
+
+
+/**
+ * Method called to inform about the decision in response to a join request.
+ *
+ * If @a is_admitted is not #GNUNET_YES, then sending messages to the channel is
+ * not possible, but earlier history can be still queried.
+ *
+ * @param cls Closure.
+ * @param is_admitted #GNUNET_YES or #GNUNET_NO or #GNUNET_SYSERR
+ * @param join_msg Application-dependent join message from the origin.
+ */
+typedef void
+(*GNUNET_PSYC_JoinDecisionCallback) (void *cls,
+ const struct GNUNET_PSYC_JoinDecisionMessage *dcsn,
+ int is_admitted,
+ const struct GNUNET_PSYC_Message *join_msg);
+
+/**
+ * Flags for GNUNET_PSYC_slave_join()
+ */
+enum GNUNET_PSYC_SlaveJoinFlags
+{
+ GNUNET_PSYC_SLAVE_JOIN_NONE = 0,
+
+ /**
+ * Local join for history access, no network connection is established.
+ */
+ GNUNET_PSYC_SLAVE_JOIN_LOCAL = 1,
+};
+
+
+/**
+ * Join a PSYC channel.
+ *
+ * The entity joining is always the local peer. The user must immediately use
+ * the GNUNET_PSYC_slave_transmit() functions to transmit a @e join_msg to the
+ * channel; if the join request succeeds, the channel state (and @e recent
+ * method calls) will be replayed to the joining member. There is no explicit
+ * notification on failure (as the channel may simply take days to approve,
+ * and disapproval is simply being ignored).
+ *
+ * @param cfg
+ * Configuration to use.
+ * @param channel_pub_key
+ * ECC public key that identifies the channel we wish to join.
+ * @param slave_pub_key
+ * ECC private-public key pair that identifies the slave, and
+ * used by multicast to sign the join request and subsequent unicast
+ * requests sent to the master.
+ * @param flags
+ * Join flags.
+ * @param origin
+ * Peer identity of the origin.
+ * @param relay_count
+ * Number of peers in the @a relays array.
+ * @param relays
+ * Peer identities of members of the multicast group, which serve
+ * as relays and used to join the group at.
+ * @param message_cb
+ * Function to invoke on message fragments received from the channel.
+ * @param message_part_cb
+ * Function to invoke on message parts received from the channel.
+ * @param slave_connect_cb
+ * Function invoked once we have connected to the PSYC service.
+ * @param join_decision_cb
+ * Function invoked once we have received a join decision.
+ * @param cls
+ * Closure for @a message_cb and @a slave_joined_cb.
+ * @param join_msg
+ * Join message.
+ *
+ * @return Handle for the slave, NULL on error.
+ */
+struct GNUNET_PSYC_Slave *
+GNUNET_PSYC_slave_join (const struct GNUNET_CONFIGURATION_Handle *cfg,
+ const struct GNUNET_CRYPTO_EddsaPublicKey *channel_pub_key,
+ const struct GNUNET_CRYPTO_EcdsaPrivateKey *slave_pub_key,
+ enum GNUNET_PSYC_SlaveJoinFlags flags,
+ const struct GNUNET_PeerIdentity *origin,
+ uint32_t relay_count,
+ const struct GNUNET_PeerIdentity *relays,
+ GNUNET_PSYC_MessageCallback message_cb,
+ GNUNET_PSYC_MessagePartCallback message_part_cb,
+ GNUNET_PSYC_SlaveConnectCallback slave_connect_cb,
+ GNUNET_PSYC_JoinDecisionCallback join_decision_cb,
+ void *cls,
+ const struct GNUNET_PSYC_Message *join_msg);
+
+
+/**
+ * Part a PSYC channel.
+ *
+ * Will terminate the connection to the PSYC service. Polite clients should
+ * first explicitly send a part request (via GNUNET_PSYC_slave_transmit()).
+ *
+ * @param slave
+ * Slave handle.
+ * @param keep_active
+ * Keep place active after last application disconnected.
+ * @param part_cb
+ * Function called after the slave parted the channel
+ * and disconnected from the psyc service.
+ * @param part_cls
+ * Closure for @a part_cb.
+ */
+void
+GNUNET_PSYC_slave_part (struct GNUNET_PSYC_Slave *slave,
+ int keep_active,
+ GNUNET_ContinuationCallback part_cb,
+ void *part_cls);
+
+
+/**
+ * Flags for transmitting messages to the channel master by a slave.
+ */
+enum GNUNET_PSYC_SlaveTransmitFlags
+{
+ GNUNET_PSYC_SLAVE_TRANSMIT_NONE = 0
+};
/**
* Handle for a pending PSYC transmission operation.
*/
-struct GNUNET_PSYC_HostTransmitHandle;
+struct GNUNET_PSYC_SlaveTransmitHandle;
/**
- * Request a message to be send to the channel host.
+ * Request a message to be sent to the channel master.
*
- * @param member membership handle
- * @param method_name which (PSYC) method should be invoked (on host)
- * @param notify function to call when we are allowed to transmit (to get data)
- * @param notify_cls closure for 'notify'
- * @return transmission handle, NULL on error (i.e. more than one request queued)
+ * @param slave Slave handle.
+ * @param method_name Which (PSYC) method should be invoked (on host).
+ * @param notify_mod Function to call to obtain modifiers.
+ * @param notify_data Function to call to obtain fragments of the data.
+ * @param notify_cls Closure for @a notify.
+ * @param flags Flags for the message being transmitted.
+ * @return Transmission handle, NULL on error (i.e. more than one request queued).
*/
-struct GNUNET_PSYC_HostTransmitHandle *
-GNUNET_PSYC_member_send_to_host (struct GNUNET_PSYC_Member *member,
- const char *method_name,
- GNUNET_PSYC_HostReadyNotify notify,
- void *notify_cls);
+struct GNUNET_PSYC_SlaveTransmitHandle *
+GNUNET_PSYC_slave_transmit (struct GNUNET_PSYC_Slave *slave,
+ const char *method_name,
+ GNUNET_PSYC_TransmitNotifyModifier notify_mod,
+ GNUNET_PSYC_TransmitNotifyData notify_data,
+ void *notify_cls,
+ enum GNUNET_PSYC_SlaveTransmitFlags flags);
/**
- * Set a (temporary, ":") variable for the next message being transmitted
- * via 'GNUNET_PSYC_member_send_to_host'. If 'GNUNET_PSYC_member_send_to_host'
- * is called and then cancelled, all variables that were set using this
- * function will be unset (lost/forgotten). To clear a variable state after
- * setting it, you can also call this function again with NULL/0 for the value.
+ * Resume transmission to the master.
*
- * @param member membership handle
- * @param variable_name name of the variable to set
- * @param value value to set for the given variable
- * @param value_size number of bytes in 'value'
+ * @param th Handle of the request that is being resumed.
*/
-uint64_t
-GNUNET_PSYC_member_host_variable_set (struct GNUNET_PSYC_Member *member,
- const char *variable_name,
- const void *value,
- size_t value_size);
+void
+GNUNET_PSYC_slave_transmit_resume (struct GNUNET_PSYC_SlaveTransmitHandle *th);
/**
- * Abort transmission request to host.
+ * Abort transmission request to master.
*
- * @param th handle of the request that is being aborted
+ * @param th Handle of the request that is being aborted.
*/
void
-GNUNET_PSYC_member_send_to_host_cancel (struct GNUNET_PSYC_HostTransmitHandle *th);
+GNUNET_PSYC_slave_transmit_cancel (struct GNUNET_PSYC_SlaveTransmitHandle *th);
/**
- * Handle to a story telling operation.
+ * Handle to access PSYC channel operations for both the master and slaves.
*/
-struct GNUNET_PSYC_Story;
+struct GNUNET_PSYC_Channel;
/**
- * Request to be told the message history of the channel. Historic
- * messages (but NOT the state at the time) will be replayed (given to
- * the normal method handlers) if available and if access is
- * permitted.
+ * Convert a channel @a master to a @e channel handle to access the @e channel
+ * APIs.
*
- * @param member which channel should be replayed?
- * @param start earliest interesting point in history
- * @param end last (exclusive) interesting point in history
- * @param finish_cb function to call when the requested story has been fully
- * told (counting message IDs might not suffice, as some messages
- * might be secret and thus the listener would not know the story is
- * finished without being told explicitly); once this function
- * has been called, the client must not call
- * 'GNUNET_PSYC_member_story_tell_cancel' anymore
- * @param finish_cb_cls closure to finish_cb
- * @return handle to cancel story telling operation
+ * @param master Channel master handle.
+ * @return Channel handle, valid for as long as @a master is valid.
*/
-struct GNUNET_PSYC_Story *
-GNUNET_PSYC_member_story_tell (struct GNUNET_PSYC_Member *member,
- uint64_t start,
- uint64_t end,
- void (*finish_cb)(void *),
- void *finish_cb_cls);
+struct GNUNET_PSYC_Channel *
+GNUNET_PSYC_master_get_channel (struct GNUNET_PSYC_Master *master);
/**
- * Abort story telling. This function must not be called from within
- * method handlers (as given to 'GNUNET_PSYC_member_join') of the
- * member.
+ * Convert @a slave to a @e channel handle to access the @e channel APIs.
*
- * @param story story telling operation to stop
+ * @param slave Slave handle.
+ * @return Channel handle, valid for as long as @a slave is valid.
+ */
+struct GNUNET_PSYC_Channel *
+GNUNET_PSYC_slave_get_channel (struct GNUNET_PSYC_Slave *slave);
+
+
+/**
+ * Add a slave to the channel's membership list.
+ *
+ * Note that this will NOT generate any PSYC traffic, it will merely update the
+ * local database to modify how we react to <em>membership test</em> queries.
+ * The channel master still needs to explicitly transmit a @e join message to
+ * notify other channel members and they then also must still call this function
+ * in their respective methods handling the @e join message. This way, how @e
+ * join and @e part operations are exactly implemented is still up to the
+ * application; for example, there might be a @e part_all method to kick out
+ * everyone.
+ *
+ * Note that channel slaves are explicitly trusted to execute such methods
+ * correctly; not doing so correctly will result in either denying other slaves
+ * access or offering access to channel data to non-members.
+ *
+ * @param channel
+ * Channel handle.
+ * @param slave_pub_key
+ * Identity of channel slave to add.
+ * @param announced_at
+ * ID of the message that announced the membership change.
+ * @param effective_since
+ * Addition of slave is in effect since this message ID.
+ * @param result_cb
+ * Function to call with the result of the operation.
+ * The @e result_code argument is #GNUNET_OK on success, or
+ * #GNUNET_SYSERR on error. In case of an error, the @e data argument
+ * can contain an optional error message.
+ * @param cls
+ * Closure for @a result_cb.
*/
void
-GNUNET_PSYC_member_story_tell_cancel (struct GNUNET_PSYC_Story *story);
+GNUNET_PSYC_channel_slave_add (struct GNUNET_PSYC_Channel *channel,
+ const struct GNUNET_CRYPTO_EcdsaPublicKey *slave_pub_key,
+ uint64_t announced_at,
+ uint64_t effective_since,
+ GNUNET_ResultCallback result_cb,
+ void *cls);
/**
- * Call the given callback on all matching values (including
- * variables) in the channel state. The callback is invoked
- * synchronously on all matching states (as the state is fully
- * replicated in the library in this process; channel states should be
- * small, large data is to be passed as streaming data to methods).
+ * Remove a slave from the channel's membership list.
+ *
+ * Note that this will NOT generate any PSYC traffic, it will merely update the
+ * local database to modify how we react to <em>membership test</em> queries.
+ * The channel master still needs to explicitly transmit a @e part message to
+ * notify other channel members and they then also must still call this function
+ * in their respective methods handling the @e part message. This way, how
+ * @e join and @e part operations are exactly implemented is still up to the
+ * application; for example, there might be a @e part_all message to kick out
+ * everyone.
*
- * A name matches if it includes the 'state_name' prefix, thus
- * requesting the empty state ("") will match all values; requesting
- * "a_b" will also return values stored under "a_b_c".
+ * Note that channel members are explicitly trusted to perform these
+ * operations correctly; not doing so correctly will result in either
+ * denying members access or offering access to channel data to
+ * non-members.
*
- * @param member membership handle
- * @param state_name name of the state to query (full name
- * might be longer, this is only the prefix that must match)
- * @param cb function to call on the matching state values
- * @param cb_cls closure for 'cb'
- * @return message ID for which the state was returned (last seen
- * message ID)
+ * @param channel
+ * Channel handle.
+ * @param slave_pub_key
+ * Identity of channel slave to remove.
+ * @param announced_at
+ * ID of the message that announced the membership change.
+ * @param result_cb
+ * Function to call with the result of the operation.
+ * The @e result_code argument is #GNUNET_OK on success, or
+ * #GNUNET_SYSERR on error. In case of an error, the @e data argument
+ * can contain an optional error message.
+ * @param cls
+ * Closure for @a result_cb.
*/
-uint64_t
-GNUNET_PSYC_member_state_get_all (struct GNUNET_PSYC_Member *member,
- const char *state_name,
- GNUNET_PSYC_StateCallback cb,
- void *cb_cls);
+void
+GNUNET_PSYC_channel_slave_remove (struct GNUNET_PSYC_Channel *channel,
+ const struct GNUNET_CRYPTO_EcdsaPublicKey
+ *slave_pub_key,
+ uint64_t announced_at,
+ GNUNET_ResultCallback result_cb,
+ void *cls);
/**
- * Obtain the current value of the best-matching value in the state
- * (including variables). Note that variables are only valid during a
- * GNUNET_PSYC_Method invocation, as variables are only valid for the
- * duration of a method invocation.
+ * History request handle.
+ */
+struct GNUNET_PSYC_HistoryRequest;
+
+
+/**
+ * Request to replay a part of the message history of the channel.
+ *
+ * Historic messages (but NOT the state at the time) will be replayed (given to
+ * the normal method handlers) if available and if access is permitted.
+ *
+ * @param channel
+ * Which channel should be replayed?
+ * @param start_message_id
+ * Earliest interesting point in history.
+ * @param end_message_id
+ * Last (inclusive) interesting point in history.
+ * @param method_prefix
+ * Retrieve only messages with a matching method prefix.
+ * @param flags
+ * OR'ed enum GNUNET_PSYC_HistoryReplayFlags
+ * @param result_cb
+ * Function to call when the requested history has been fully replayed.
+ * Once this function has been called, the client must not call
+ * GNUNET_PSYC_channel_history_replay_cancel() anymore.
+ * @param cls
+ * Closure for the callbacks.
+ *
+ * @return Handle to cancel history replay operation.
+ */
+struct GNUNET_PSYC_HistoryRequest *
+GNUNET_PSYC_channel_history_replay (struct GNUNET_PSYC_Channel *channel,
+ uint64_t start_message_id,
+ uint64_t end_message_id,
+ const char *method_prefix,
+ uint32_t flags,
+ GNUNET_PSYC_MessageCallback message_cb,
+ GNUNET_PSYC_MessagePartCallback message_part_cb,
+ GNUNET_ResultCallback result_cb,
+ void *cls);
+
+
+/**
+ * Request to replay the latest messages from the message history of the channel.
+ *
+ * Historic messages (but NOT the state at the time) will be replayed (given to
+ * the normal method handlers) if available and if access is permitted.
+ *
+ * @param channel
+ * Which channel should be replayed?
+ * @param message_limit
+ * Maximum number of messages to replay.
+ * @param flags
+ * OR'ed enum GNUNET_PSYC_HistoryReplayFlags
+ * @param finish_cb
+ * Function to call when the requested history has been fully replayed
+ * (counting message IDs might not suffice, as some messages might be
+ * secret and thus the listener would not know the story is finished
+ * without being told explicitly)o once this function has been called, the
+ * client must not call GNUNET_PSYC_channel_history_replay_cancel() anymore.
+ * @param cls
+ * Closure for the callbacks.
+ *
+ * @return Handle to cancel history replay operation.
+ */
+struct GNUNET_PSYC_HistoryRequest *
+GNUNET_PSYC_channel_history_replay_latest (struct GNUNET_PSYC_Channel *channel,
+ uint64_t message_limit,
+ const char *method_prefix,
+ uint32_t flags,
+ GNUNET_PSYC_MessageCallback message_cb,
+ GNUNET_PSYC_MessagePartCallback message_part_cb,
+ GNUNET_ResultCallback result_cb,
+ void *cls);
+
+
+void
+GNUNET_PSYC_channel_history_replay_cancel (struct GNUNET_PSYC_Channel *channel,
+ struct GNUNET_PSYC_HistoryRequest *hr);
+
+
+/**
+ * Function called to inform a member about stored state values for a channel.
+ *
+ * If @a full_value_size > value_size then this function is called multiple
+ * times until the whole value arrived.
+ *
+ * @param cls
+ * Closure.
+ * @param name
+ * Name of the state variable.
+ * NULL if there are no more state variables to be returned.
+ * @param value
+ * Value of the state variable.
+ * @param value_size
+ * Number of bytes in @a value.
+ * @param full_value_size
+ * Number of bytes in the full value, including continuations.
+ * Only set for the first part of a variable,
+ * in case of a continuation it is 0.
+ */
+typedef void
+(*GNUNET_PSYC_StateVarCallback) (void *cls,
+ const struct GNUNET_MessageHeader *mod,
+ const char *name,
+ const void *value,
+ uint32_t value_size,
+ uint32_t full_value_size);
+
+
+/**
+ * State request handle.
+ */
+struct GNUNET_PSYC_StateRequest;
+
+
+/**
+ * Retrieve the best matching channel state variable.
*
- * If the requested variable name does not have an exact state in
- * the state, the nearest less-specific name is matched; for example,
- * requesting "a_b" will match "a" if "a_b" does not exist.
+ * If the requested variable name is not present in the state, the nearest
+ * less-specific name is matched; for example, requesting "_a_b" will match "_a"
+ * if "_a_b" does not exist.
*
- * @param member membership handle
- * @param variable_name name of the variable to query
- * @param return_value_size set to number of bytes in variable,
- * needed as variables might contain binary data and
- * might also not be 0-terminated; set to 0 on errors
- * @return NULL on error (no matching state or variable), pointer
- to the respective value otherwise
+ * @param channel
+ * Channel handle.
+ * @param full_name
+ * Full name of the requested variable.
+ * The actual variable returned might have a shorter name.
+ * @param var_cb
+ * Function called once when a matching state variable is found.
+ * Not called if there's no matching state variable.
+ * @param result_cb
+ * Function called after the operation finished.
+ * (i.e. all state variables have been returned via @a state_cb)
+ * @param cls
+ * Closure for the callbacks.
*/
-const void *
-GNUNET_PSYC_member_state_get (struct GNUNET_PSYC_Member *member,
- const char *variable_name,
- size_t *return_value_size);
+struct GNUNET_PSYC_StateRequest *
+GNUNET_PSYC_channel_state_get (struct GNUNET_PSYC_Channel *channel,
+ const char *full_name,
+ GNUNET_PSYC_StateVarCallback var_cb,
+ GNUNET_ResultCallback result_cb,
+ void *cls);
+
+
+/**
+ * Return all channel state variables whose name matches a given prefix.
+ *
+ * A name matches if it starts with the given @a name_prefix, thus requesting
+ * the empty prefix ("") will match all values; requesting "_a_b" will also
+ * return values stored under "_a_b_c".
+ *
+ * The @a state_cb is invoked on all matching state variables asynchronously, as
+ * the state is stored in and retrieved from the PSYCstore,
+ *
+ * @param channel
+ * Channel handle.
+ * @param name_prefix
+ * Prefix of the state variable name to match.
+ * @param var_cb
+ * Function called once when a matching state variable is found.
+ * Not called if there's no matching state variable.
+ * @param result_cb
+ * Function called after the operation finished.
+ * (i.e. all state variables have been returned via @a state_cb)
+ * @param cls
+ * Closure for the callbacks.
+ */
+struct GNUNET_PSYC_StateRequest *
+GNUNET_PSYC_channel_state_get_prefix (struct GNUNET_PSYC_Channel *channel,
+ const char *name_prefix,
+ GNUNET_PSYC_StateVarCallback var_cb,
+ GNUNET_ResultCallback result_cb,
+ void *cls);
+
+/**
+ * Cancel a state request operation.
+ *
+ * @param sr
+ * Handle for the operation to cancel.
+ */
+void
+GNUNET_PSYC_channel_state_get_cancel (struct GNUNET_PSYC_StateRequest *sr);
/* ifndef GNUNET_PSYC_SERVICE_H */
#endif
-/* end of gnunet_psyc_service.h */
+
+/** @} */ /* end of group */