/*
* This file is part of GNUnet
* Copyright (C) 2013 GNUnet e.V.
*
* GNUnet is free software: you can redistribute it and/or modify it
* under the terms of the GNU Affero General Public License as published
* by the Free Software Foundation, either version 3 of the License,
* or (at your option) any later version.
*
* GNUnet is distributed in the hope that it will be useful, but
* WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* Affero General Public License for more details.
*
* You should have received a copy of the GNU Affero General Public License
* along with this program. If not, see .
*/
/**
* @file psyc/psyc_api.c
* @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
*/
#include
#include "platform.h"
#include "gnunet_util_lib.h"
#include "gnunet_multicast_service.h"
#include "gnunet_psyc_service.h"
#include "gnunet_psyc_util_lib.h"
#include "psyc.h"
#define LOG(kind,...) GNUNET_log_from (kind, "psyc-api",__VA_ARGS__)
/**
* Handle to access PSYC channel operations for both the master and slaves.
*/
struct GNUNET_PSYC_Channel
{
/**
* Configuration to use.
*/
const struct GNUNET_CONFIGURATION_Handle *cfg;
/**
* Client connection to the service.
*/
struct GNUNET_MQ_Handle *mq;
/**
* Message to send on connect.
*/
struct GNUNET_MQ_Envelope *connect_env;
/**
* Time to wait until we try to reconnect on failure.
*/
struct GNUNET_TIME_Relative reconnect_delay;
/**
* Task for reconnecting when the listener fails.
*/
struct GNUNET_SCHEDULER_Task *reconnect_task;
/**
* Async operations.
*/
struct GNUNET_OP_Handle *op;
/**
* Transmission handle;
*/
struct GNUNET_PSYC_TransmitHandle *tmit;
/**
* Receipt handle;
*/
struct GNUNET_PSYC_ReceiveHandle *recv;
/**
* Function called after disconnected from the service.
*/
GNUNET_ContinuationCallback disconnect_cb;
/**
* Closure for @a disconnect_cb.
*/
void *disconnect_cls;
/**
* Are we polling for incoming messages right now?
*/
uint8_t in_receive;
/**
* Is this a master or slave channel?
*/
uint8_t is_master;
/**
* Is this channel in the process of disconnecting from the service?
* #GNUNET_YES or #GNUNET_NO
*/
uint8_t is_disconnecting;
};
/**
* Handle for the master of a PSYC channel.
*/
struct GNUNET_PSYC_Master
{
struct GNUNET_PSYC_Channel chn;
GNUNET_PSYC_MasterStartCallback start_cb;
/**
* Join request callback.
*/
GNUNET_PSYC_JoinRequestCallback join_req_cb;
/**
* Closure for the callbacks.
*/
void *cb_cls;
};
/**
* Handle for a PSYC channel slave.
*/
struct GNUNET_PSYC_Slave
{
struct GNUNET_PSYC_Channel chn;
GNUNET_PSYC_SlaveConnectCallback connect_cb;
GNUNET_PSYC_JoinDecisionCallback join_dcsn_cb;
/**
* Closure for the callbacks.
*/
void *cb_cls;
};
/**
* Handle that identifies a join request.
*
* Used to match calls to #GNUNET_PSYC_JoinRequestCallback to the
* corresponding calls to GNUNET_PSYC_join_decision().
*/
struct GNUNET_PSYC_JoinHandle
{
struct GNUNET_PSYC_Master *mst;
struct GNUNET_CRYPTO_EcdsaPublicKey slave_pub_key;
};
/**
* Handle for a pending PSYC transmission operation.
*/
struct GNUNET_PSYC_SlaveTransmitHandle
{
};
struct GNUNET_PSYC_HistoryRequest
{
/**
* Channel.
*/
struct GNUNET_PSYC_Channel *chn;
/**
* Operation ID.
*/
uint64_t op_id;
/**
* Message handler.
*/
struct GNUNET_PSYC_ReceiveHandle *recv;
/**
* Function to call when the operation finished.
*/
GNUNET_ResultCallback result_cb;
/**
* Closure for @a result_cb.
*/
void *cls;
};
struct GNUNET_PSYC_StateRequest
{
/**
* Channel.
*/
struct GNUNET_PSYC_Channel *chn;
/**
* Operation ID.
*/
uint64_t op_id;
/**
* State variable result callback.
*/
GNUNET_PSYC_StateVarCallback var_cb;
/**
* Function to call when the operation finished.
*/
GNUNET_ResultCallback result_cb;
/**
* Closure for @a result_cb.
*/
void *cls;
};
static int
check_channel_result (void *cls,
const struct GNUNET_OperationResultMessage *res)
{
return GNUNET_OK;
}
static void
handle_channel_result (void *cls,
const struct GNUNET_OperationResultMessage *res)
{
struct GNUNET_PSYC_Channel *chn = cls;
uint16_t size = ntohs (res->header.size);
if (size < sizeof (*res))
{ /* Error, message too small. */
GNUNET_break (0);
return;
}
uint16_t data_size = size - sizeof (*res);
const char *data = (0 < data_size) ? (void *) &res[1] : NULL;
GNUNET_OP_result (chn->op, GNUNET_ntohll (res->op_id),
GNUNET_ntohll (res->result_code),
data, data_size, NULL);
GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
"handle_channel_result: Received result message with OP ID %" PRIu64 "\n",
GNUNET_ntohll (res->op_id));
}
static void
op_recv_history_result (void *cls, int64_t result,
const void *data, uint16_t data_size)
{
LOG (GNUNET_ERROR_TYPE_DEBUG,
"Received history replay result: %" PRId64 ".\n", result);
struct GNUNET_PSYC_HistoryRequest *hist = cls;
if (NULL != hist->result_cb)
hist->result_cb (hist->cls, result, data, data_size);
GNUNET_PSYC_receive_destroy (hist->recv);
GNUNET_free (hist);
}
static void
op_recv_state_result (void *cls, int64_t result,
const void *data, uint16_t data_size)
{
LOG (GNUNET_ERROR_TYPE_DEBUG,
"Received state request result: %" PRId64 ".\n", result);
struct GNUNET_PSYC_StateRequest *sr = cls;
if (NULL != sr->result_cb)
sr->result_cb (sr->cls, result, data, data_size);
GNUNET_free (sr);
}
static int
check_channel_history_result (void *cls,
const struct GNUNET_OperationResultMessage *res)
{
struct GNUNET_PSYC_MessageHeader *
pmsg = (struct GNUNET_PSYC_MessageHeader *) GNUNET_MQ_extract_nested_mh (res);
uint16_t size = ntohs (res->header.size);
if ( (NULL == pmsg) ||
(size < sizeof (*res) + sizeof (*pmsg)) )
{ /* Error, message too small. */
GNUNET_break_op (0);
return GNUNET_SYSERR;
}
return GNUNET_OK;
}
static void
handle_channel_history_result (void *cls,
const struct GNUNET_OperationResultMessage *res)
{
struct GNUNET_PSYC_Channel *chn = cls;
struct GNUNET_PSYC_MessageHeader *
pmsg = (struct GNUNET_PSYC_MessageHeader *) GNUNET_MQ_extract_nested_mh (res);
GNUNET_ResultCallback result_cb = NULL;
struct GNUNET_PSYC_HistoryRequest *hist = NULL;
LOG (GNUNET_ERROR_TYPE_DEBUG,
"%p Received historic fragment for message #%" PRIu64 ".\n",
chn,
GNUNET_ntohll (pmsg->message_id));
if (GNUNET_YES != GNUNET_OP_get (chn->op,
GNUNET_ntohll (res->op_id),
&result_cb, (void *) &hist, NULL))
{ /* Operation not found. */
LOG (GNUNET_ERROR_TYPE_WARNING,
"%p Replay operation not found for historic fragment of message #%"
PRIu64 ".\n",
chn, GNUNET_ntohll (pmsg->message_id));
return;
}
GNUNET_PSYC_receive_message (hist->recv,
(const struct GNUNET_PSYC_MessageHeader *) pmsg);
}
static int
check_channel_state_result (void *cls,
const struct GNUNET_OperationResultMessage *res)
{
const struct GNUNET_MessageHeader *mod = GNUNET_MQ_extract_nested_mh (res);
uint16_t mod_size;
uint16_t size;
if (NULL == mod)
{
GNUNET_break_op (0);
return GNUNET_SYSERR;
}
mod_size = ntohs (mod->size);
size = ntohs (res->header.size);
if (size - sizeof (*res) != mod_size)
{
GNUNET_break_op (0);
return GNUNET_SYSERR;
}
return GNUNET_OK;
}
static void
handle_channel_state_result (void *cls,
const struct GNUNET_OperationResultMessage *res)
{
struct GNUNET_PSYC_Channel *chn = cls;
GNUNET_ResultCallback result_cb = NULL;
struct GNUNET_PSYC_StateRequest *sr = NULL;
if (GNUNET_YES != GNUNET_OP_get (chn->op,
GNUNET_ntohll (res->op_id),
&result_cb, (void *) &sr, NULL))
{ /* Operation not found. */
return;
}
const struct GNUNET_MessageHeader *mod = GNUNET_MQ_extract_nested_mh (res);
if (NULL == mod)
{
GNUNET_break_op (0);
return;
}
uint16_t mod_size = ntohs (mod->size);
switch (ntohs (mod->type))
{
case GNUNET_MESSAGE_TYPE_PSYC_MESSAGE_MODIFIER:
{
const struct GNUNET_PSYC_MessageModifier *
pmod = (const struct GNUNET_PSYC_MessageModifier *) mod;
const char *name = (const char *) &pmod[1];
uint16_t name_size = ntohs (pmod->name_size);
if (0 == name_size
|| mod_size - sizeof (*pmod) < name_size
|| '\0' != name[name_size - 1])
{
GNUNET_break_op (0);
return;
}
sr->var_cb (sr->cls, mod, name, name + name_size,
ntohs (pmod->header.size) - sizeof (*pmod),
ntohs (pmod->value_size));
break;
}
case GNUNET_MESSAGE_TYPE_PSYC_MESSAGE_MOD_CONT:
sr->var_cb (sr->cls, mod, NULL, (const char *) &mod[1],
mod_size - sizeof (*mod), 0);
break;
}
}
static int
check_channel_message (void *cls,
const struct GNUNET_PSYC_MessageHeader *pmsg)
{
return GNUNET_OK;
}
static void
handle_channel_message (void *cls,
const struct GNUNET_PSYC_MessageHeader *pmsg)
{
struct GNUNET_PSYC_Channel *chn = cls;
GNUNET_PSYC_receive_message (chn->recv, pmsg);
}
static void
handle_channel_message_ack (void *cls,
const struct GNUNET_MessageHeader *msg)
{
struct GNUNET_PSYC_Channel *chn = cls;
GNUNET_PSYC_transmit_got_ack (chn->tmit);
}
static void
handle_master_start_ack (void *cls,
const struct GNUNET_PSYC_CountersResultMessage *cres)
{
struct GNUNET_PSYC_Master *mst = cls;
int32_t result = ntohl (cres->result_code);
if (GNUNET_OK != result && GNUNET_NO != result)
{
LOG (GNUNET_ERROR_TYPE_ERROR, "Could not start master: %ld\n", result);
GNUNET_break (0);
/* FIXME: disconnect */
}
if (NULL != mst->start_cb)
mst->start_cb (mst->cb_cls, result, GNUNET_ntohll (cres->max_message_id));
}
static int
check_master_join_request (void *cls,
const struct GNUNET_PSYC_JoinRequestMessage *req)
{
if ( ((sizeof (*req) + sizeof (struct GNUNET_PSYC_Message)) <= ntohs (req->header.size)) &&
(NULL == GNUNET_MQ_extract_nested_mh (req)) )
{
GNUNET_break_op (0);
return GNUNET_SYSERR;
}
return GNUNET_OK;
}
static void
handle_master_join_request (void *cls,
const struct GNUNET_PSYC_JoinRequestMessage *req)
{
struct GNUNET_PSYC_Master *mst = cls;
if (NULL == mst->join_req_cb)
return;
const struct GNUNET_PSYC_Message *join_msg = NULL;
if (sizeof (*req) + sizeof (*join_msg) <= ntohs (req->header.size))
{
join_msg = (struct GNUNET_PSYC_Message *) GNUNET_MQ_extract_nested_mh (req);
LOG (GNUNET_ERROR_TYPE_DEBUG,
"Received join_msg of type %u and size %u.\n",
ntohs (join_msg->header.type),
ntohs (join_msg->header.size));
}
struct GNUNET_PSYC_JoinHandle *jh = GNUNET_malloc (sizeof (*jh));
jh->mst = mst;
jh->slave_pub_key = req->slave_pub_key;
if (NULL != mst->join_req_cb)
mst->join_req_cb (mst->cb_cls, req, &req->slave_pub_key, join_msg, jh);
}
static void
handle_slave_join_ack (void *cls,
const struct GNUNET_PSYC_CountersResultMessage *cres)
{
struct GNUNET_PSYC_Slave *slv = cls;
int32_t result = ntohl (cres->result_code);
if (GNUNET_YES != result && GNUNET_NO != result)
{
LOG (GNUNET_ERROR_TYPE_ERROR, "Could not join slave.\n");
GNUNET_break (0);
/* FIXME: disconnect */
}
if (NULL != slv->connect_cb)
slv->connect_cb (slv->cb_cls, result, GNUNET_ntohll (cres->max_message_id));
}
static int
check_slave_join_decision (void *cls,
const struct GNUNET_PSYC_JoinDecisionMessage *dcsn)
{
return GNUNET_OK;
}
static void
handle_slave_join_decision (void *cls,
const struct GNUNET_PSYC_JoinDecisionMessage *dcsn)
{
struct GNUNET_PSYC_Slave *slv = cls;
struct GNUNET_PSYC_Message *pmsg = NULL;
if (ntohs (dcsn->header.size) <= sizeof (*dcsn) + sizeof (*pmsg))
pmsg = (struct GNUNET_PSYC_Message *) &dcsn[1];
if (NULL != slv->join_dcsn_cb)
slv->join_dcsn_cb (slv->cb_cls, dcsn, ntohl (dcsn->is_admitted), pmsg);
}
static void
channel_cleanup (struct GNUNET_PSYC_Channel *chn)
{
GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
"cleaning up channel %p\n",
chn);
if (NULL != chn->tmit)
{
GNUNET_PSYC_transmit_destroy (chn->tmit);
chn->tmit = NULL;
}
if (NULL != chn->recv)
{
GNUNET_PSYC_receive_destroy (chn->recv);
chn->recv = NULL;
}
if (NULL != chn->connect_env)
{
GNUNET_MQ_discard (chn->connect_env);
chn->connect_env = NULL;
}
if (NULL != chn->mq)
{
GNUNET_MQ_destroy (chn->mq);
chn->mq = NULL;
}
if (NULL != chn->disconnect_cb)
{
chn->disconnect_cb (chn->disconnect_cls);
chn->disconnect_cb = NULL;
}
GNUNET_free (chn);
}
static void
handle_channel_part_ack (void *cls,
const struct GNUNET_MessageHeader *msg)
{
struct GNUNET_PSYC_Channel *chn = cls;
channel_cleanup (chn);
}
/*** MASTER ***/
static void
master_connect (struct GNUNET_PSYC_Master *mst);
static void
master_reconnect (void *cls)
{
master_connect (cls);
}
/**
* Master client disconnected from service.
*
* Reconnect after backoff period.
*/
static void
master_disconnected (void *cls, enum GNUNET_MQ_Error error)
{
struct GNUNET_PSYC_Master *mst = cls;
struct GNUNET_PSYC_Channel *chn = &mst->chn;
LOG (GNUNET_ERROR_TYPE_DEBUG,
"Master client disconnected (%d), re-connecting\n",
(int) error);
if (NULL != chn->tmit)
{
GNUNET_PSYC_transmit_destroy (chn->tmit);
chn->tmit = NULL;
}
if (NULL != chn->mq)
{
GNUNET_MQ_destroy (chn->mq);
chn->mq = NULL;
}
chn->reconnect_task = GNUNET_SCHEDULER_add_delayed (chn->reconnect_delay,
master_reconnect,
mst);
chn->reconnect_delay = GNUNET_TIME_STD_BACKOFF (chn->reconnect_delay);
}
static void
master_connect (struct GNUNET_PSYC_Master *mst)
{
struct GNUNET_PSYC_Channel *chn = &mst->chn;
struct GNUNET_MQ_MessageHandler handlers[] = {
GNUNET_MQ_hd_fixed_size (master_start_ack,
GNUNET_MESSAGE_TYPE_PSYC_MASTER_START_ACK,
struct GNUNET_PSYC_CountersResultMessage,
mst),
GNUNET_MQ_hd_var_size (master_join_request,
GNUNET_MESSAGE_TYPE_PSYC_JOIN_REQUEST,
struct GNUNET_PSYC_JoinRequestMessage,
mst),
GNUNET_MQ_hd_fixed_size (channel_part_ack,
GNUNET_MESSAGE_TYPE_PSYC_PART_ACK,
struct GNUNET_MessageHeader,
chn),
GNUNET_MQ_hd_var_size (channel_message,
GNUNET_MESSAGE_TYPE_PSYC_MESSAGE,
struct GNUNET_PSYC_MessageHeader,
chn),
GNUNET_MQ_hd_fixed_size (channel_message_ack,
GNUNET_MESSAGE_TYPE_PSYC_MESSAGE_ACK,
struct GNUNET_MessageHeader,
chn),
GNUNET_MQ_hd_var_size (channel_history_result,
GNUNET_MESSAGE_TYPE_PSYC_HISTORY_RESULT,
struct GNUNET_OperationResultMessage,
chn),
GNUNET_MQ_hd_var_size (channel_state_result,
GNUNET_MESSAGE_TYPE_PSYC_STATE_RESULT,
struct GNUNET_OperationResultMessage,
chn),
GNUNET_MQ_hd_var_size (channel_result,
GNUNET_MESSAGE_TYPE_PSYC_RESULT_CODE,
struct GNUNET_OperationResultMessage,
chn),
GNUNET_MQ_handler_end ()
};
chn->mq = GNUNET_CLIENT_connect (chn->cfg,
"psyc",
handlers,
&master_disconnected,
mst);
GNUNET_assert (NULL != chn->mq);
chn->tmit = GNUNET_PSYC_transmit_create (chn->mq);
GNUNET_MQ_send_copy (chn->mq, chn->connect_env);
}
/**
* Start a PSYC master channel.
*
* 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 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 message_cb Function to invoke on message parts received from slaves.
* @param join_request_cb Function to invoke when a slave wants to join.
* @param master_start_cb Function to invoke after the channel master started.
* @param cls Closure for @a method and @a join_cb.
*
* @return Handle for the channel master, NULL on error.
*/
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 start_cb,
GNUNET_PSYC_JoinRequestCallback join_request_cb,
GNUNET_PSYC_MessageCallback message_cb,
GNUNET_PSYC_MessagePartCallback message_part_cb,
void *cls)
{
struct GNUNET_PSYC_Master *mst = GNUNET_new (struct GNUNET_PSYC_Master);
struct GNUNET_PSYC_Channel *chn = &mst->chn;
struct MasterStartRequest *req;
chn->connect_env = GNUNET_MQ_msg (req,
GNUNET_MESSAGE_TYPE_PSYC_MASTER_START);
req->channel_key = *channel_key;
req->policy = policy;
chn->cfg = cfg;
chn->is_master = GNUNET_YES;
chn->reconnect_delay = GNUNET_TIME_UNIT_MILLISECONDS;
chn->op = GNUNET_OP_create ();
chn->recv = GNUNET_PSYC_receive_create (message_cb, message_part_cb, cls);
mst->start_cb = start_cb;
mst->join_req_cb = join_request_cb;
mst->cb_cls = cls;
master_connect (mst);
return mst;
}
/**
* Stop a PSYC master channel.
*
* @param master PSYC channel master to stop.
* @param keep_active FIXME
*/
void
GNUNET_PSYC_master_stop (struct GNUNET_PSYC_Master *mst,
int keep_active,
GNUNET_ContinuationCallback stop_cb,
void *stop_cls)
{
struct GNUNET_PSYC_Channel *chn = &mst->chn;
struct GNUNET_MQ_Envelope *env;
chn->is_disconnecting = GNUNET_YES;
chn->disconnect_cb = stop_cb;
chn->disconnect_cls = stop_cls;
env = GNUNET_MQ_msg_header (GNUNET_MESSAGE_TYPE_PSYC_PART_REQUEST);
GNUNET_MQ_send (chn->mq, env);
}
/**
* 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.
*
* @return #GNUNET_OK on success,
* #GNUNET_SYSERR if the message 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)
{
struct GNUNET_PSYC_Channel *chn = &jh->mst->chn;
struct GNUNET_PSYC_JoinDecisionMessage *dcsn;
uint16_t join_resp_size
= (NULL != join_resp) ? ntohs (join_resp->header.size) : 0;
uint16_t relay_size = relay_count * sizeof (*relays);
if (GNUNET_MULTICAST_FRAGMENT_MAX_PAYLOAD
< sizeof (*dcsn) + relay_size + join_resp_size)
return GNUNET_SYSERR;
struct GNUNET_MQ_Envelope *
env = GNUNET_MQ_msg_extra (dcsn, relay_size + join_resp_size,
GNUNET_MESSAGE_TYPE_PSYC_JOIN_DECISION);
dcsn->is_admitted = htonl (is_admitted);
dcsn->slave_pub_key = jh->slave_pub_key;
if (0 < join_resp_size)
GNUNET_memcpy (&dcsn[1], join_resp, join_resp_size);
GNUNET_MQ_send (chn->mq, env);
GNUNET_free (jh);
return GNUNET_OK;
}
/**
* Send a message to call a method to all members in the PSYC channel.
*
* @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_transmit (struct GNUNET_PSYC_Master *mst,
const char *method_name,
GNUNET_PSYC_TransmitNotifyModifier notify_mod,
GNUNET_PSYC_TransmitNotifyData notify_data,
void *notify_cls,
enum GNUNET_PSYC_MasterTransmitFlags flags)
{
if (GNUNET_OK
== GNUNET_PSYC_transmit_message (mst->chn.tmit, method_name, NULL,
notify_mod, notify_data, notify_cls,
flags))
return (struct GNUNET_PSYC_MasterTransmitHandle *) mst->chn.tmit;
else
return NULL;
}
/**
* Resume transmission to the channel.
*
* @param tmit Handle of the request that is being resumed.
*/
void
GNUNET_PSYC_master_transmit_resume (struct GNUNET_PSYC_MasterTransmitHandle *tmit)
{
GNUNET_PSYC_transmit_resume ((struct GNUNET_PSYC_TransmitHandle *) tmit);
}
/**
* Abort transmission request to the channel.
*
* @param tmit Handle of the request that is being aborted.
*/
void
GNUNET_PSYC_master_transmit_cancel (struct GNUNET_PSYC_MasterTransmitHandle *tmit)
{
GNUNET_PSYC_transmit_cancel ((struct GNUNET_PSYC_TransmitHandle *) tmit);
}
/**
* Convert a channel @a master to a @e channel handle to access the @e channel
* APIs.
*
* @param master Channel master handle.
*
* @return Channel handle, valid for as long as @a master is valid.
*/
struct GNUNET_PSYC_Channel *
GNUNET_PSYC_master_get_channel (struct GNUNET_PSYC_Master *master)
{
return &master->chn;
}
/*** SLAVE ***/
static void
slave_connect (struct GNUNET_PSYC_Slave *slv);
static void
slave_reconnect (void *cls)
{
slave_connect (cls);
}
/**
* Slave client disconnected from service.
*
* Reconnect after backoff period.
*/
static void
slave_disconnected (void *cls,
enum GNUNET_MQ_Error error)
{
struct GNUNET_PSYC_Slave *slv = cls;
struct GNUNET_PSYC_Channel *chn = &slv->chn;
LOG (GNUNET_ERROR_TYPE_DEBUG,
"Slave client disconnected (%d), re-connecting\n",
(int) error);
if (NULL != chn->tmit)
{
GNUNET_PSYC_transmit_destroy (chn->tmit);
chn->tmit = NULL;
}
if (NULL != chn->mq)
{
GNUNET_MQ_destroy (chn->mq);
chn->mq = NULL;
}
chn->reconnect_task = GNUNET_SCHEDULER_add_delayed (chn->reconnect_delay,
&slave_reconnect,
slv);
chn->reconnect_delay = GNUNET_TIME_STD_BACKOFF (chn->reconnect_delay);
}
static void
slave_connect (struct GNUNET_PSYC_Slave *slv)
{
struct GNUNET_PSYC_Channel *chn = &slv->chn;
struct GNUNET_MQ_MessageHandler handlers[] = {
GNUNET_MQ_hd_fixed_size (slave_join_ack,
GNUNET_MESSAGE_TYPE_PSYC_SLAVE_JOIN_ACK,
struct GNUNET_PSYC_CountersResultMessage,
slv),
GNUNET_MQ_hd_var_size (slave_join_decision,
GNUNET_MESSAGE_TYPE_PSYC_JOIN_DECISION,
struct GNUNET_PSYC_JoinDecisionMessage,
slv),
GNUNET_MQ_hd_fixed_size (channel_part_ack,
GNUNET_MESSAGE_TYPE_PSYC_PART_ACK,
struct GNUNET_MessageHeader,
chn),
GNUNET_MQ_hd_var_size (channel_message,
GNUNET_MESSAGE_TYPE_PSYC_MESSAGE,
struct GNUNET_PSYC_MessageHeader,
chn),
GNUNET_MQ_hd_fixed_size (channel_message_ack,
GNUNET_MESSAGE_TYPE_PSYC_MESSAGE_ACK,
struct GNUNET_MessageHeader,
chn),
GNUNET_MQ_hd_var_size (channel_history_result,
GNUNET_MESSAGE_TYPE_PSYC_HISTORY_RESULT,
struct GNUNET_OperationResultMessage,
chn),
GNUNET_MQ_hd_var_size (channel_state_result,
GNUNET_MESSAGE_TYPE_PSYC_STATE_RESULT,
struct GNUNET_OperationResultMessage,
chn),
GNUNET_MQ_hd_var_size (channel_result,
GNUNET_MESSAGE_TYPE_PSYC_RESULT_CODE,
struct GNUNET_OperationResultMessage,
chn),
GNUNET_MQ_handler_end ()
};
chn->mq = GNUNET_CLIENT_connect (chn->cfg,
"psyc",
handlers,
&slave_disconnected,
slv);
if (NULL == chn->mq)
{
chn->reconnect_task = GNUNET_SCHEDULER_add_delayed (chn->reconnect_delay,
&slave_reconnect,
slv);
chn->reconnect_delay = GNUNET_TIME_STD_BACKOFF (chn->reconnect_delay);
return;
}
chn->tmit = GNUNET_PSYC_transmit_create (chn->mq);
GNUNET_MQ_send_copy (chn->mq, chn->connect_env);
}
/**
* 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_key ECC public key that identifies the channel we wish to join.
* @param slave_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 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 parts received from the
* channel, typically at least contains method handlers for @e join and
* @e part.
* @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 method_name Method name for the join request.
* @param env Environment containing transient variables for the request, or NULL.
* @param data Payload for the join message.
* @param data_size Number of bytes in @a data.
*
* @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_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 connect_cb,
GNUNET_PSYC_JoinDecisionCallback join_decision_cb,
void *cls,
const struct GNUNET_PSYC_Message *join_msg)
{
struct GNUNET_PSYC_Slave *slv = GNUNET_malloc (sizeof (*slv));
struct GNUNET_PSYC_Channel *chn = &slv->chn;
uint16_t relay_size = relay_count * sizeof (*relays);
uint16_t join_msg_size;
if (NULL == join_msg)
join_msg_size = 0;
else
join_msg_size = ntohs (join_msg->header.size);
struct SlaveJoinRequest *req;
chn->connect_env = GNUNET_MQ_msg_extra (req, relay_size + join_msg_size,
GNUNET_MESSAGE_TYPE_PSYC_SLAVE_JOIN);
req->channel_pub_key = *channel_pub_key;
req->slave_key = *slave_key;
req->origin = *origin;
req->relay_count = htonl (relay_count);
req->flags = htonl (flags);
if (0 < relay_size)
GNUNET_memcpy (&req[1], relays, relay_size);
if (NULL != join_msg)
GNUNET_memcpy ((char *) &req[1] + relay_size, join_msg, join_msg_size);
chn->cfg = cfg;
chn->is_master = GNUNET_NO;
chn->reconnect_delay = GNUNET_TIME_UNIT_MILLISECONDS;
chn->op = GNUNET_OP_create ();
chn->recv = GNUNET_PSYC_receive_create (message_cb, message_part_cb, cls);
slv->connect_cb = connect_cb;
slv->join_dcsn_cb = join_decision_cb;
slv->cb_cls = cls;
slave_connect (slv);
return slv;
}
/**
* 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.
*/
void
GNUNET_PSYC_slave_part (struct GNUNET_PSYC_Slave *slv,
int keep_active,
GNUNET_ContinuationCallback part_cb,
void *part_cls)
{
struct GNUNET_PSYC_Channel *chn = &slv->chn;
struct GNUNET_MQ_Envelope *env;
chn->is_disconnecting = GNUNET_YES;
chn->disconnect_cb = part_cb;
chn->disconnect_cls = part_cls;
env = GNUNET_MQ_msg_header (GNUNET_MESSAGE_TYPE_PSYC_PART_REQUEST);
GNUNET_MQ_send (chn->mq, env);
}
/**
* Request a message to be sent to the channel master.
*
* @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_SlaveTransmitHandle *
GNUNET_PSYC_slave_transmit (struct GNUNET_PSYC_Slave *slv,
const char *method_name,
GNUNET_PSYC_TransmitNotifyModifier notify_mod,
GNUNET_PSYC_TransmitNotifyData notify_data,
void *notify_cls,
enum GNUNET_PSYC_SlaveTransmitFlags flags)
{
if (GNUNET_OK
== GNUNET_PSYC_transmit_message (slv->chn.tmit, method_name, NULL,
notify_mod, notify_data, notify_cls,
flags))
return (struct GNUNET_PSYC_SlaveTransmitHandle *) slv->chn.tmit;
else
return NULL;
}
/**
* Resume transmission to the master.
*
* @param tmit Handle of the request that is being resumed.
*/
void
GNUNET_PSYC_slave_transmit_resume (struct GNUNET_PSYC_SlaveTransmitHandle *tmit)
{
GNUNET_PSYC_transmit_resume ((struct GNUNET_PSYC_TransmitHandle *) tmit);
}
/**
* Abort transmission request to master.
*
* @param tmit Handle of the request that is being aborted.
*/
void
GNUNET_PSYC_slave_transmit_cancel (struct GNUNET_PSYC_SlaveTransmitHandle *tmit)
{
GNUNET_PSYC_transmit_cancel ((struct GNUNET_PSYC_TransmitHandle *) tmit);
}
/**
* Convert @a slave to a @e channel handle to access the @e channel APIs.
*
* @param slv 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 *slv)
{
return &slv->chn;
}
/**
* 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 membership test 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 chn
* 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_channel_slave_add (struct GNUNET_PSYC_Channel *chn,
const struct GNUNET_CRYPTO_EcdsaPublicKey *slave_pub_key,
uint64_t announced_at,
uint64_t effective_since,
GNUNET_ResultCallback result_cb,
void *cls)
{
struct ChannelMembershipStoreRequest *req;
struct GNUNET_MQ_Envelope *
env = GNUNET_MQ_msg (req, GNUNET_MESSAGE_TYPE_PSYC_CHANNEL_MEMBERSHIP_STORE);
req->slave_pub_key = *slave_pub_key;
req->announced_at = GNUNET_htonll (announced_at);
req->effective_since = GNUNET_htonll (effective_since);
req->did_join = GNUNET_YES;
req->op_id = GNUNET_htonll (GNUNET_OP_add (chn->op, result_cb, cls, NULL));
GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
"GNUNET_PSYC_channel_slave_add, OP ID: %" PRIu64 "\n",
GNUNET_ntohll (req->op_id));
GNUNET_MQ_send (chn->mq, env);
}
/**
* 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 membership test 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.
*
* 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 chn
* 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.
*/
void
GNUNET_PSYC_channel_slave_remove (struct GNUNET_PSYC_Channel *chn,
const struct GNUNET_CRYPTO_EcdsaPublicKey *slave_pub_key,
uint64_t announced_at,
GNUNET_ResultCallback result_cb,
void *cls)
{
struct ChannelMembershipStoreRequest *req;
struct GNUNET_MQ_Envelope *
env = GNUNET_MQ_msg (req, GNUNET_MESSAGE_TYPE_PSYC_CHANNEL_MEMBERSHIP_STORE);
req->slave_pub_key = *slave_pub_key;
req->announced_at = GNUNET_htonll (announced_at);
req->did_join = GNUNET_NO;
req->op_id = GNUNET_htonll (GNUNET_OP_add (chn->op, result_cb, cls, NULL));
GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
"GNUNET_PSYC_channel_slave_remove, OP ID: %" PRIu64 "\n",
GNUNET_ntohll (req->op_id));
GNUNET_MQ_send (chn->mq, env);
}
static struct GNUNET_PSYC_HistoryRequest *
channel_history_replay (struct GNUNET_PSYC_Channel *chn,
uint64_t start_message_id,
uint64_t end_message_id,
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)
{
struct GNUNET_PSYC_HistoryRequestMessage *req;
struct GNUNET_PSYC_HistoryRequest *hist = GNUNET_malloc (sizeof (*hist));
hist->chn = chn;
hist->recv = GNUNET_PSYC_receive_create (message_cb, message_part_cb, cls);
hist->result_cb = result_cb;
hist->cls = cls;
hist->op_id = GNUNET_OP_add (chn->op, op_recv_history_result, hist, NULL);
GNUNET_assert (NULL != method_prefix);
uint16_t method_size = strnlen (method_prefix,
GNUNET_MAX_MESSAGE_SIZE
- sizeof (*req)) + 1;
GNUNET_assert ('\0' == method_prefix[method_size - 1]);
struct GNUNET_MQ_Envelope *
env = GNUNET_MQ_msg_extra (req, method_size,
GNUNET_MESSAGE_TYPE_PSYC_HISTORY_REPLAY);
req->start_message_id = GNUNET_htonll (start_message_id);
req->end_message_id = GNUNET_htonll (end_message_id);
req->message_limit = GNUNET_htonll (message_limit);
req->flags = htonl (flags);
req->op_id = GNUNET_htonll (hist->op_id);
GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
"channel_history_replay, OP ID: %" PRIu64 "\n",
GNUNET_ntohll (req->op_id));
GNUNET_memcpy (&req[1], method_prefix, method_size);
GNUNET_MQ_send (chn->mq, env);
return hist;
}
/**
* Request to replay a part of the message history of the channel.
*
* Historic messages (but NOT the state at the time) will be replayed and given
* to the normal method handlers with a #GNUNET_PSYC_MESSAGE_HISTORIC flag set.
*
* Messages are retrieved from the local PSYCstore if available,
* otherwise requested from the network.
*
* @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.
* @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 *chn,
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)
{
return channel_history_replay (chn, start_message_id, end_message_id, 0,
method_prefix, flags,
message_cb, message_part_cb, result_cb, 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 method_prefix
* Retrieve only messages with a matching method prefix.
* Use NULL or "" to retrieve all.
* @param flags
* OR'ed enum GNUNET_PSYC_HistoryReplayFlags
* @param result_cb
* Function to call when the requested history has been fully replayed.
* @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 *chn,
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)
{
return channel_history_replay (chn, 0, 0, message_limit, method_prefix, flags,
message_cb, message_part_cb, result_cb, cls);
}
void
GNUNET_PSYC_channel_history_replay_cancel (struct GNUNET_PSYC_Channel *channel,
struct GNUNET_PSYC_HistoryRequest *hist)
{
GNUNET_PSYC_receive_destroy (hist->recv);
GNUNET_OP_remove (hist->chn->op, hist->op_id);
GNUNET_free (hist);
}
/**
* Retrieve the best matching channel state variable.
*
* 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 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.
*/
static struct GNUNET_PSYC_StateRequest *
channel_state_get (struct GNUNET_PSYC_Channel *chn,
uint16_t type, const char *name,
GNUNET_PSYC_StateVarCallback var_cb,
GNUNET_ResultCallback result_cb, void *cls)
{
struct StateRequest *req;
struct GNUNET_PSYC_StateRequest *sr = GNUNET_malloc (sizeof (*sr));
sr->chn = chn;
sr->var_cb = var_cb;
sr->result_cb = result_cb;
sr->cls = cls;
sr->op_id = GNUNET_OP_add (chn->op, op_recv_state_result, sr, NULL);
GNUNET_assert (NULL != name);
size_t name_size = strnlen (name, GNUNET_MAX_MESSAGE_SIZE
- sizeof (*req)) + 1;
struct GNUNET_MQ_Envelope *
env = GNUNET_MQ_msg_extra (req, name_size, type);
req->op_id = GNUNET_htonll (sr->op_id);
GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
"channel_state_get, OP ID: %" PRIu64 "\n",
GNUNET_ntohll (req->op_id));
GNUNET_memcpy (&req[1], name, name_size);
GNUNET_MQ_send (chn->mq, env);
return sr;
}
/**
* Retrieve the best matching channel state variable.
*
* 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 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.
*/
struct GNUNET_PSYC_StateRequest *
GNUNET_PSYC_channel_state_get (struct GNUNET_PSYC_Channel *chn,
const char *full_name,
GNUNET_PSYC_StateVarCallback var_cb,
GNUNET_ResultCallback result_cb,
void *cls)
{
return channel_state_get (chn, GNUNET_MESSAGE_TYPE_PSYC_STATE_GET,
full_name, var_cb, result_cb, 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 *chn,
const char *name_prefix,
GNUNET_PSYC_StateVarCallback var_cb,
GNUNET_ResultCallback result_cb,
void *cls)
{
return channel_state_get (chn, GNUNET_MESSAGE_TYPE_PSYC_STATE_GET_PREFIX,
name_prefix, var_cb, result_cb, 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)
{
GNUNET_OP_remove (sr->chn->op, sr->op_id);
GNUNET_free (sr);
}
/* end of psyc_api.c */